Objective: To explore the expression of transferrin(Tf) and transferrin receptor(Tf R) in hematoma brain tissue at different stage after intracerebral hemorrhage(ICH) in rats. Methods: ICH rats model were established ...Objective: To explore the expression of transferrin(Tf) and transferrin receptor(Tf R) in hematoma brain tissue at different stage after intracerebral hemorrhage(ICH) in rats. Methods: ICH rats model were established by collagenase method, and rats were sacrificed at 24 h, 72 h, 7 d and 14 d after operation. The levels of Tf and Tf R in different periods of rats were detected by immunohistochemical method, and correlation between two groups was analyzed. Results: Tf, Tf R-positive cells at each time after operation in observation group were significantly higher than that in control group(P<0.05). Tf, Tf R-positive cells began to increase from 24 h after the operation and reached the peak 72 h-7 d after surgery, but then gradually decreased. Tf was mainly expressed in nucleus and cytoplasm of neurons and glial cells around the hematoma, but Tf R was mainly expressed in nucleus and cytoplasm of neurons and choroid plexus endothelial cells. Correlation analysis showed that the Tf-positive cell was significantly positively correlated with Tf R-positive cell expression(r=0.447, P=0.022). Conclusions: Tf and Tf R were important transporters in brain tissue excessive load iron transport after ICH, and detecting the expression levels of the two indicators can provide a reference for prognosis treatmentin ICH.展开更多
The binding of Tb 3+ to chicken apoovotransferrin was studied by monitoring the fluorescent intensity of Tb 3+ at 549 nm. The conditional equilibrium constants for the complexation of Tb 3+ by chicken apoovotransferri...The binding of Tb 3+ to chicken apoovotransferrin was studied by monitoring the fluorescent intensity of Tb 3+ at 549 nm. The conditional equilibrium constants for the complexation of Tb 3+ by chicken apoovotransferrin in 0 1 mol/L hepes, at pH 7 4 and room temperature were measured. The successive macroscopic binding constants are lg K 1=9 08±0 12 and lg K 2=7 36±0 22. The molar fluorescence enhancement of Tb 3+ apoovotransferrin complex is (2 06±0 14)×10 4 mol -1 ·L. The fluorescence quenching experiment and the titration of N terminal monoferric ovotransferrin showed that Tb 3+ has a preference for being bound to the N terminal binding site of apoovotransferrin.展开更多
Previous studies demonstrate an accumulation of transferrin and transferrin receptor 1(TfR1) in regenerating peripheral nerves.However, the expression and function of transferrin and TfR1 in the denervated skeletal mu...Previous studies demonstrate an accumulation of transferrin and transferrin receptor 1(TfR1) in regenerating peripheral nerves.However, the expression and function of transferrin and TfR1 in the denervated skeletal muscle remain poorly understood.In this study, a mouse model of denervation was produced by complete tear of the left brachial plexus nerve.RNA-sequencing revealed that transferrin expression in the denervated skeletal muscle was upregulated, while TfR1 expression was downregulated.We also investigated the function of TfR1 during development and in adult skeletal muscles in mice with inducible deletion or loss of TfR1.The ablation of TfR1 in skeletal muscle in early development caused severe muscular atrophy and early death.In comparison, deletion of TfR1 in adult skeletal muscles did not affect survival or glucose metabolism, but caused skeletal muscle atrophy and motor functional impairment, similar to the muscular atrophy phenotype observed after denervation.These findings suggest that TfR1 plays an important role in muscle development and denervation-induced muscular atrophy.This study was approved by the Institutional Animal Care and Use Committee of Beijing Institute of Basic Medical Sciences, China(approval No.SYXK 2017-C023) on June 1, 2018.展开更多
This paper addressed the international transferring t endency of manufacturing industry one by one as follows: (1) The developed count ries realize manufacturing industry structure upgrade reling on worldwide tr ansfe...This paper addressed the international transferring t endency of manufacturing industry one by one as follows: (1) The developed count ries realize manufacturing industry structure upgrade reling on worldwide tr ansference not only domestic transference. On one hand, the TNCs make cross-inv estments, transnational merger & acquisition so as to achieve the optimum colloc ation of R&D resources, and obtain innovation in knowledge and technology. On th e other hand, the developed countries transfer labor and resource intensive indu stry as well as the labor-intensive link of the production chain in highly tech nology industry to the developing countries, to make their industrial structure escalation. (2) The adjustment and upgrade of manufacturing industry presents "m ulti-step type". First, the object of international transference substitutes th e capital-intensive industry and maturing industry with complicate technique fo r the industry with labor-intensive, simple technique or higher pollution, or s ubstitutes non-core complex technological procedure and parts and components fo r assembly in manufacturing process. Secondly, technology transference forms "br ain-hand and foot" pattern, i.e. the developed countries are increasingly p aying more and more attention to the research and control of core technology, th us transferring simple technique and labor-intensive procedure in higher scienc e and technology. Thirdly, the developed countries begins to transfer both capit al and technology intensive production, as well as transfer certain procedures i n higher technology production process to a few developing countries, even t o transfer parts of R & D to developing countries. (3) TNCs promote the global m anufacturing network (GMN) by recombination and transfer. TNCs organize producti on, trade, technological research and transference through foreign direct invest ment (FDI) all over the world, as a result, GMN makes the national competence no longer depend on absolute occupation of certain industries, but on national com prehensive strength and comparative superiority. TNCs try to race to seize the h igher location of industrial value chain, only leaving the core technology and h igher value-added chains in mother countries, on the other hand, they transfer lower manufacturing power more and more to other countries. (4) TNCs transfer th eir domestic manufacturing bases abroad, China would become world- manufacturin g center. Chinese market is increasingly arousing foreign investor’s interest, " Made in China" will be a synonym of manufacturing industry in new century, subst ituting for "Made in U.S.", "Made in Japanese" and "Made in Europe". The Chinese manufacturing industry should hold tightly the opportunity to melt into the wor ldwide recombination and transfer and enter GMN, so as to accomplish leaping dev elopment.展开更多
Objective:To assess the association between genetic variants of transferrin receptor 2(TFR2)exon 4 and anemia status and to describe the expression levels of several cytokines,hepcidin,soluble transferrin receptor and...Objective:To assess the association between genetic variants of transferrin receptor 2(TFR2)exon 4 and anemia status and to describe the expression levels of several cytokines,hepcidin,soluble transferrin receptor and erythropoietin.Methods:Institutional based comparative study was done randomly to recruit 106 pregnant women who attended antenatal care in three different health centers in Boyolali Regency,Central Java from May 2015 to September 2015.DNA was extracted from peripheral blood samples of selected pregnant women and sequencing was done for TFR2 exon 4.Furthermore,enzyme-linked immunosorbent assay was conducted to measure the expression levels of interleukin 6,interleukin 4,transforming growth factorβand iron-metabolism related proteins such as hepcidin,soluble transferrin receptor,and erythropoietin.Gene alignment was performed by using a CLUSTAL W program.Collected data were analyzed statistically by using parametric and nonparametric tests with Statistical Product and Service Solutions(SPSS)20.0 for Windows.Results:Three novel genetic variants from TFR2 exon 4(position 603,605 and 606)were associated with anemia status.Moreover,the expression levels of interleukin 6,interleukin 4,transforming growth factorβand erythropoietin were higher in anemic pregnant women than those of nonanemic pregnant women but only erythropoietin level reached statistical significance.These results were followed by decreases of hepcidin and soluble transferrin receptor levels.Conclusions:Various factors contribute to anemia prevalence among pregnant women in Boyoali Regency,Central Java,Indonesia.Our novel findings showed that TFR2 exon 4 has 3 mutational sites in position 603,605 and 606.These novel genetic variants may provide a new insight into the role of TFR2 in anemia.展开更多
The yellow pond turtle Mauremys mutica is widely cultured using both greenhouse-reared and outdoor pond-reared models.Individuals from the two models often show different tolerances to dramatic temperature changes cau...The yellow pond turtle Mauremys mutica is widely cultured using both greenhouse-reared and outdoor pond-reared models.Individuals from the two models often show different tolerances to dramatic temperature changes caused by extreme weather events.However,the mechanism underlying the difference is unclear.In this study,we found that for greenhouse-reared turtles(GRTs),the expression levels of an immune-related gene for transferrin were significantly different(P<0.05)between the control group and the acute cold stress(ACS)group for most time points(3 h,6 h and 48 h),while at two time points(6 h and 12 h)there was a significant difference(P<0.05)between the control group and the acute heat stress(AHS)group.However,for the outdoor pond-reared turtles(OPTs),we found the opposite pattern:the ACS group showed no significant difference(P>0.05)from the control group for all time points(3 h,6 h,12 h,24 h and 48 h),whereas two time points(12 h and 24 h)were significantly different(P<0.05)for the AHS group.Our results indicate that ACS may influence the immunity of GRTs and have no influence on OPTs,whereas AHS may largely affect the immunity of OPTs and have little influence on GRTs.The findings provide insights into the mechanism underlying the different morbidity and mortality rates of turtles from different culture models after extreme weather events.展开更多
Selecting an ideal molecular format from diverse structures is a major challenge in developing a bispecific antibody(BsAb).To choose an ideal format of anti-CD3 x anti-transferrin receptor(TfR)bispecific antibodies fo...Selecting an ideal molecular format from diverse structures is a major challenge in developing a bispecific antibody(BsAb).To choose an ideal format of anti-CD3 x anti-transferrin receptor(TfR)bispecific antibodies for clinical application,we constructed TfR bispecific T-cell engager(BiTE)in two extensively applied formats,including single-chain tandem singlechain variable fragments(scFvs)and double-chain diabodies,and evaluated their functional characterizations in vitro.Results demonstrated that TfR-BiTE in both formats directed potent killing of TfR+HepG2 cells.However,compared to two・chain diabodies,scFvs were more efficient in antigen binding and TfR target killing.Furthermore,different domain orders in scFvs would also be evaluated because single-TfR-CD3-His was preferable to single-CD3-TfR-His in immunotherapeutic strategies.Thus,the single-chain tandem TfR-CD3 format was favored for further investigation in cancer therapy.展开更多
Objective: To investigate the effect of high throughput hemodialysis on soluble transferrin receptor in hemodialysis patients and the improvement of renal anemia. Methods: 132 patients receiving maintenance hemodialys...Objective: To investigate the effect of high throughput hemodialysis on soluble transferrin receptor in hemodialysis patients and the improvement of renal anemia. Methods: 132 patients receiving maintenance hemodialysis in our hospital from July 2017 to July 2019 were selected and divided into control group and observation group according to the random number table method, with 66 cases each. The observation group was treated with high-flux hemodialysis, while the control group was treated with low-flux hemodialysis for 6 months. Compare two groups before and after treatment serum beta 2 microglobulin (beta 2 - MG), serum creatinine (Scr), blood urea nitrogen (BUN) level, anemia related index [red blood cells deposited (HCT), hemoglobin (Hb), reticulocyte percentage (Ret%)], iron metabolism index [serum ferritin (SF), transferrin saturation (TSAT)、Hepcidin(Hepc)], soluble transferrin receptor (sTfR) levels and adverse reactions. Results: the levels of 2-MG, Scr and BUN in the two groups before treatment were compared (P>0.05). After treatment, Scr and BUN levels in the two groups were significantly decreased (P<0.05), but were compared between the two groups (P>0.05). The level of 2-MG in the observation group was lower than that in the control group (P<0.05). Before treatment, sTfR, Hb, HCT level and Ret% of the two groups were compared(P>0.05). After treatment, Hb and HCT levels in the observation group were higher than those in the control group, while Ret% were lower than those in the control group, (P<0.05). Before treatment, the levels of ST、TAST、sTfR and Hepc in the two groups were compared (P>0.05). After treatment, the level of ST and TAST in the observation group was higher than that in the control group, The levels of sTfR and Hepc were lower than the control group (P<0.05). The overall incidence of adverse reactions in the observation group (8.93%) was lower than that in the control group (10.14%), with no significant difference (P>0.05). Conclusion: The high-throughput hemodialysis department significantly improved renal anemia in hemodialysis patients, reduced serum sTfR level, and had fewer adverse reactions and higher safety.展开更多
Hypochromic microcytic anaemia includes iron deficiency, anaemia of chronic disorders, beta thalassemia trait and sideroblastic anaemia. To rule out the cause of hypochromic microcytic anaemia is a diagnostic difficul...Hypochromic microcytic anaemia includes iron deficiency, anaemia of chronic disorders, beta thalassemia trait and sideroblastic anaemia. To rule out the cause of hypochromic microcytic anaemia is a diagnostic difficulty. The conventional laboratory tests used for diagnosis have few disadvantages. Serum transferrin receptor (sTfR) is the most reliable method for assessment of body iron. Eighty four children were included in this study. They were further divided into four groups: iron deficiency anaemia (IDA), anaemia of chronic disorders (ACD), beta thalassemia trait (β TT) and controls. Children withIDAand ACD were diagnosed on the basis of history and serum iron profile. Subjects with β TT had HbA2 > 3.5%. sTfR were performed on all subjects. Level of sTfR in patients withIDAwas 5.79 μg/ml ± 1.3 μg/ml. In patients with anaemia of chronic disorders (ACD), β thalassemia trait and controls mean sTfR were 2.18 μg/ml ± 0.6 μg/ml, 2.1μg/ml ± 0.5 μg/ml and 2.0 μg/ml ± 0.5 μg/ml respectively. These results show level of sTfR was raised in IDA when compared with controls or ACD and β TT (p展开更多
Objective: To study the correlation of serum hepcidin (HEP) and transferrin receptor (sTfR) contents with iron deficiency and micro-inflammatory response in patients with hemodialysis. Methods: Patients undergoing mai...Objective: To study the correlation of serum hepcidin (HEP) and transferrin receptor (sTfR) contents with iron deficiency and micro-inflammatory response in patients with hemodialysis. Methods: Patients undergoing maintenance hemodialysis in the Jingzhou Central Hospital between June 2014 and March 2017 were selected as MHD group, healthy volunteers receiving physical examination during the same period were selected as control group, serum was collected to determine the levels of HEP, sTfR, iron deficiency indexes, inflammatory response indexes and oxidative stress indexes, and the correlation between indicators was analyzed. Results: Serum HEP, sTfR, TNF-α, IL-17, IL-23, NOX2 and MDA levels of MHD group were higher than those of control group while SF, TRF, Aeplin, IL-10, SOD, GSH-P and TAC levels were lower than those of control group;serum Aeplin, IL-10, SOD, GSH-P and TAC levels of MHD group were negatively correlated with SF and TRF levels whereas the TNF-α, IL-17, IL-23, NOX2 and MDA levels were positively correlated with SF and TRF levels. Conclusions: The increase of serum HEP and sTfR in patients with hemodialysis can reflect the degree of iron deficiency and is closely related to the degree of micro-inflammatory response.展开更多
Objective The present study was designed to explore the correlations between prealbumin(PA),transferrin(TF),handgrip strength and nutrition risk screening tool 2002(NRS 2002),patient-generated subjective global assess...Objective The present study was designed to explore the correlations between prealbumin(PA),transferrin(TF),handgrip strength and nutrition risk screening tool 2002(NRS 2002),patient-generated subjective global assessment(PG-SGA)in preoperative nutritional screening and evaluation in gastric cancer patients.Methods 132 cases of gastric cancer patients undergoing surgical treatment from May 2015 to January 2018 were screened and evaluated by NRS 2002 and PG-SGA within 48 h after admission,and the PA,TF and handgrip strength were measured for each patient.Results The levels of PA,TF,and handgrip strength in the nutritional risk group(NRS 2002≥3)and the malnutrition group(PG-SGA≥4)were significantly lower than that in non-nutrition risk group(NRS 2002<3)and non-malnutrition group(PG-SGA<4).The levels of PA,TF,and handgrip strength of preoperative patients were negatively correlated with NRS 2002 and PG-SGA scores(P<0.05).NRS 2002 and PG-SGA scores were positively correlated(r=0.712,P<0.01).Conclusion The preoperative nutritional risk and malnutrition rate in patients with gastric cancer are high.The combined application of PA,TF,handgrip strength,NRS 2002,and PG-SGA is more helpful for nutritional screening and assessment in gastric cancer patients.展开更多
AIM: To construct fusion protein of a single-chain antibody(scFv) against transferrin receptor (TfR) with alkalinephosphatase (AP).METHODS: The VH-linker-VL, namely scFv gene, wasprepared by amplifying the VH and VL g...AIM: To construct fusion protein of a single-chain antibody(scFv) against transferrin receptor (TfR) with alkalinephosphatase (AP).METHODS: The VH-linker-VL, namely scFv gene, wasprepared by amplifying the VH and VL genes from plasmid pGEM-T-VH and pGEM-T-VL with splicing overlap extension polymerase chain reaction (SOE PCR). After the ScFv gene was modified by SfiⅠ and NotⅠ, it was subcloned into the secretory expression vector pUC19/119, and then was transformed into E. coli TG1. The positive colonies were screened by colony PCR and their expressions were induced by IPTG. ScFv gene was gained by digesting ScFv expression vector pUC19/119 with Sfi I and NotⅠ restriction enzymes, then subcloned into expression vector pDAP2, followed by transformation in E. coli TG1. The positive colonies were selected by bacterial colony PCR. The expression of fusion protein (scFv-AP) was induced by IPTG. Its activity was detected by enzyme immunoassay. The molecular weights of scFv and scFv-AP were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).RESULTS: The product of SOE PCR formed a band of 700 bp in agarose gel electrophoresis. SDS-PAGE demonstrated the molecular weight of scFv was 27 ku. Immunofluorescent assay (IFA) demonstrated its reactivity with TfR. The molecular weight of scFv-AP was 75 ku. Enzyme immunoassay showed that scFv-AP could specifically bind to human TfR and play AP activity.CONCLUSION: We have successfully prepared the antihuman TfR scFv and constructed the fusion protein of scFv and AP. It is promising for immunological experiments.展开更多
AIM: To evaluate the sensitivity and specificity of transfesrrin dipstick test (Tf) in colorectal cancer (CRC) screening and precancerous lesions screening. METHODS: Eight hundreds and sixty-one individuals at high-ri...AIM: To evaluate the sensitivity and specificity of transfesrrin dipstick test (Tf) in colorectal cancer (CRC) screening and precancerous lesions screening. METHODS: Eight hundreds and sixty-one individuals at high-risk for CRC were recruited. Six hundreds and eleven subsequently received the three fecal occult blood tests and colonoscopy with biopsy performed as needed. Fecal samples were obtained on the day before colonoscopy. Tf, immuno fecal occult blood test (IFOBT) and guaiac fecal occult blood test (g-FOBT) were performed simultaneously on the same stool. To minimize false-negative cases, all subjects with negative samples were asked to provide an additional stool specimen for a second test even a third test. If the results were all negative after testing three repeated samples, the subject was considered a true negative. The performance characteristics of Tf for detecting CRC and precancerous lesions were examined and compared to those of IFOBT and the combination of Tf, IFOBT and g-FOBT. RESULTS: A total of six hundreds and eleven subjects met the study criteria including 25 with CRC and 60 with precancerous lesions. Sensitivity for detecting CRC was 92% for Tf and 96% for IFOBT, specificities of Tf and IFOBT were both 72.0% (95% CI: 68.2%-75.5%; χ2 = 0.4, P > 0.05); positive likelihood ratios of those were 3.3 (95% CI: 2.8-3.9) and 3.4 (95% CI: 2.9-4.0), respectively. In precancerous lesions, sensitivities for Tf and IFOBT were 50% and 58%, respectively (χ 2 = 0.8, P > 0.05); specificities of Tf and IFOBT were 71.5% (95% CI: 67.6%-75.1%) and 72.2% (95% CI: 68.4%-75.8%); positive likelihood ratios of those were 1.8 (95% CI: 1.3-2.3) and 2.1 (95% CI: 1.6-2.7), respectively; compared to IFOBT, g-FOBT+ Tf+ IFOBT had a significantly higher positive rate for precancerous lesions (83% vs 58%, respectively; χ 2 = 9.1, P < 0.05). In patients with CRC and precancerous lesions, the sensitivities of Tf and IFOBT were 62% and 69% (χ 2 = 0.9, P > 0.05); specificities of those were 74.5% (95% CI: 70.6%-78.1%) and 75.5% (95% CI: 71.6%-79.0%); positive likelihood ratios of those were 2.5 (95% CI: 2.0-3.1) and 2.8 (95% CI: 2.3-3.5). Compared to IF-OBT alone, combining g-FOBT, IFOBT and Tf led to significantly increased sensitivity for detecting CRC and cancerous lesions (69% vs 88%, respectively; χ 2 = 9.0, P < 0.05). CONCLUSION: Tf dipstick test might be used as an ad- ditional tool for CRC and precancerous lesions screening in a high-risk cohort.展开更多
Objective To establish and evaluate a protein microarray method for combined measurement of serum ferritin(SF) and soluble transferrin receptor(sTfR).Methods Microarrayer was used to print both anti-SF antibodies I an...Objective To establish and evaluate a protein microarray method for combined measurement of serum ferritin(SF) and soluble transferrin receptor(sTfR).Methods Microarrayer was used to print both anti-SF antibodies I and anti-sTfR antibodies I on each protein microarray.Anti-SF antibodies II and anti-sTfR antibodies II were used as detection antibodies and goat antibodies coupled to Cy3 were used as antibodies III.The detection conditions of the quantitative analysis method for simultaneous measurement of SF and sTfR with protein microarray were optimized and evaluated.The protein microarray was compared with commercially available traditional tests with 26 serum samples.Results By comparison experiment,mouse monoclonal antibodies were chosen as the probes and contact printing was chosen as the printing method.The concentrations of SF and sTfR probes were 0.5 mg/mL and 0.5 mg/mL respectively,while those of SF and sTfR detection antibodies were 5 μg/mL and 0.36 μg/mL respectively.Intra-and inter-assay variability was between 3.26% and 18.38% for all tests.The regression coefficients comparing protein microarray with traditional test assays were better than 0.81 for SF and sTfR.Conclusion The present study has established a protein microarray method for combined measurement of SF and sTfR.展开更多
Iron is an essential trophic element that is required for cell viability and differentiation, especially in oligodendrocytes, which consume relatively high rates of energy to produce myelin. Multiple iron metabolism p...Iron is an essential trophic element that is required for cell viability and differentiation, especially in oligodendrocytes, which consume relatively high rates of energy to produce myelin. Multiple iron metabolism proteins are expressed in the brain including transferrin receptor and ferritin-H. However, it is still unknown whether they are developmentally regulated in oligodendrocyte lineage cells for myelination. Here, using an in vitro cultured differentiation model of oligodendrocytes, we found that both transferrin receptor and ferritin-H are significantly upregulated during oligodendrocyte maturation, implying the essential role of iron in the development of oligodendrocytes. Additional different doses of Fe3+ in the cultured medium did not affect oligodendrocyte precursor cell maturation or ferritin-H expression but decreased the expression of the transferrin receptor. These results indicate that upregulation of both transferrin receptor and ferritin-H contributes to maturation and myelination of oligodendrocyte precursor cells.展开更多
In the present study, we used immunohistochemistry and western blot analysis to examine changes in the levels and cellular localization of iron, heavy chain ferritin(ferritin-H), and transferrin in the gerbil hippocam...In the present study, we used immunohistochemistry and western blot analysis to examine changes in the levels and cellular localization of iron, heavy chain ferritin(ferritin-H), and transferrin in the gerbil hippocampal CA1 region from 30 minutes to 7 days following transient forebrain ischemia. Relative to sham controls, iron reactivity increased significantly in the stratum pyramidale and stratum oriens at 12 hours following ischemic insult, transiently decreased at 1–2 days and then increased once again within the CA1 region at 4–7 days after ischemia. One day after ischemia, ferritin-H immunoreactivity increased significantly in the stratum pyramidale and decreased at 2 days. At 4–7 days after ischemia, ferritin-H immunoreactivity in the glial components in the CA1 region was significantly increased. Transferrin immunoreactivity was increased significantly in the stratum pyramidale at 12 hours, peaked at 1 day, and then decreased significantly at 2 days after ischemia. Seven days after ischemia, Transferrin immunoreactivity in the glial cells of the stratum oriens and radiatum was significantly increased. Western blot analyses supported these results, demonstrating that compared to sham controls, ferritin H and transferrin protein levels in hippocampal homogenates significantly increased at 1 day after ischemia, peaked at 4 days and then decreased. These results suggest that iron overload-induced oxidative stress is most prominent at 12 hours after ischemia in the stratum pyramidale, suggesting that this time window may be the optimal period for therapeutic intervention to protect neurons from ischemia-induced death.展开更多
Transferrin(TF) and its isoforms have been widely reported via various analytical techniques, including a noticeable increased number of isoforms with low content of sialic acid(asialo-, monosialo-, and disialo-transf...Transferrin(TF) and its isoforms have been widely reported via various analytical techniques, including a noticeable increased number of isoforms with low content of sialic acid(asialo-, monosialo-, and disialo-transferrin) and asialo-TF as well as disialo-TF, with one or several oligosaccharides released in human serum transferrin(hTf). Here, hTf has been purified by native gradient polyacrylamide gel electrophoresis(PAGENG) before use. The hTf extracted with the electron-transfer approach showed a single subunit band(77.1 Da) in the SDS-PAGE gel, but it exhibited two bands in the native and denatured isoelectric focusing(IEF) gels, namely, hTf-2Fe3+ and apo-hTf, without finding any other transferrin isoforms. A reversed phase HPLC(RP-HPLC) equipped with a C18 column effectively separated hTf and its polymers and combined off-line techniques, including peptide mass fingerprinting(PMF), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS) and database search, and identified the high homology among hTf, apo-hTf, and their isoforms. Moreover, the elution solution consisting of acetonitrile and formic acid could easily denature both hTf and apo-hTf to form various isoforms during separation with HPLC, indicating that chemical factors lead to the formation of various isoforms in transferrin, artificially, during extraction and separation. The authors claimed that only two transferrin isoforms existed in the NHS, namely, hTf-2Fe3+ and apo-hTf, which could be employed in biomarkers, to distinguish the healthy population from many disease sufferers, such as, carbohydrate-deficient transferrin(CDT).展开更多
The work described the synthesis and evaluation of PEI–g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and...The work described the synthesis and evaluation of PEI–g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5 (mol/mol). The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.展开更多
基金supported by 2012 Kunshan Instruction Subject(KS1254)
文摘Objective: To explore the expression of transferrin(Tf) and transferrin receptor(Tf R) in hematoma brain tissue at different stage after intracerebral hemorrhage(ICH) in rats. Methods: ICH rats model were established by collagenase method, and rats were sacrificed at 24 h, 72 h, 7 d and 14 d after operation. The levels of Tf and Tf R in different periods of rats were detected by immunohistochemical method, and correlation between two groups was analyzed. Results: Tf, Tf R-positive cells at each time after operation in observation group were significantly higher than that in control group(P<0.05). Tf, Tf R-positive cells began to increase from 24 h after the operation and reached the peak 72 h-7 d after surgery, but then gradually decreased. Tf was mainly expressed in nucleus and cytoplasm of neurons and glial cells around the hematoma, but Tf R was mainly expressed in nucleus and cytoplasm of neurons and choroid plexus endothelial cells. Correlation analysis showed that the Tf-positive cell was significantly positively correlated with Tf R-positive cell expression(r=0.447, P=0.022). Conclusions: Tf and Tf R were important transporters in brain tissue excessive load iron transport after ICH, and detecting the expression levels of the two indicators can provide a reference for prognosis treatmentin ICH.
文摘The binding of Tb 3+ to chicken apoovotransferrin was studied by monitoring the fluorescent intensity of Tb 3+ at 549 nm. The conditional equilibrium constants for the complexation of Tb 3+ by chicken apoovotransferrin in 0 1 mol/L hepes, at pH 7 4 and room temperature were measured. The successive macroscopic binding constants are lg K 1=9 08±0 12 and lg K 2=7 36±0 22. The molar fluorescence enhancement of Tb 3+ apoovotransferrin complex is (2 06±0 14)×10 4 mol -1 ·L. The fluorescence quenching experiment and the titration of N terminal monoferric ovotransferrin showed that Tb 3+ has a preference for being bound to the N terminal binding site of apoovotransferrin.
基金supported by the National Natural Science Foundation of China, Nos.31770929(to HTW), 31522029(to HTW), 81902847(to HHY)the Beijing Municipal Science and Technology Commission of China, Nos.Z181100001518001(to HTW), Z161100000216154(to HTW)。
文摘Previous studies demonstrate an accumulation of transferrin and transferrin receptor 1(TfR1) in regenerating peripheral nerves.However, the expression and function of transferrin and TfR1 in the denervated skeletal muscle remain poorly understood.In this study, a mouse model of denervation was produced by complete tear of the left brachial plexus nerve.RNA-sequencing revealed that transferrin expression in the denervated skeletal muscle was upregulated, while TfR1 expression was downregulated.We also investigated the function of TfR1 during development and in adult skeletal muscles in mice with inducible deletion or loss of TfR1.The ablation of TfR1 in skeletal muscle in early development caused severe muscular atrophy and early death.In comparison, deletion of TfR1 in adult skeletal muscles did not affect survival or glucose metabolism, but caused skeletal muscle atrophy and motor functional impairment, similar to the muscular atrophy phenotype observed after denervation.These findings suggest that TfR1 plays an important role in muscle development and denervation-induced muscular atrophy.This study was approved by the Institutional Animal Care and Use Committee of Beijing Institute of Basic Medical Sciences, China(approval No.SYXK 2017-C023) on June 1, 2018.
文摘This paper addressed the international transferring t endency of manufacturing industry one by one as follows: (1) The developed count ries realize manufacturing industry structure upgrade reling on worldwide tr ansference not only domestic transference. On one hand, the TNCs make cross-inv estments, transnational merger & acquisition so as to achieve the optimum colloc ation of R&D resources, and obtain innovation in knowledge and technology. On th e other hand, the developed countries transfer labor and resource intensive indu stry as well as the labor-intensive link of the production chain in highly tech nology industry to the developing countries, to make their industrial structure escalation. (2) The adjustment and upgrade of manufacturing industry presents "m ulti-step type". First, the object of international transference substitutes th e capital-intensive industry and maturing industry with complicate technique fo r the industry with labor-intensive, simple technique or higher pollution, or s ubstitutes non-core complex technological procedure and parts and components fo r assembly in manufacturing process. Secondly, technology transference forms "br ain-hand and foot" pattern, i.e. the developed countries are increasingly p aying more and more attention to the research and control of core technology, th us transferring simple technique and labor-intensive procedure in higher scienc e and technology. Thirdly, the developed countries begins to transfer both capit al and technology intensive production, as well as transfer certain procedures i n higher technology production process to a few developing countries, even t o transfer parts of R & D to developing countries. (3) TNCs promote the global m anufacturing network (GMN) by recombination and transfer. TNCs organize producti on, trade, technological research and transference through foreign direct invest ment (FDI) all over the world, as a result, GMN makes the national competence no longer depend on absolute occupation of certain industries, but on national com prehensive strength and comparative superiority. TNCs try to race to seize the h igher location of industrial value chain, only leaving the core technology and h igher value-added chains in mother countries, on the other hand, they transfer lower manufacturing power more and more to other countries. (4) TNCs transfer th eir domestic manufacturing bases abroad, China would become world- manufacturin g center. Chinese market is increasingly arousing foreign investor’s interest, " Made in China" will be a synonym of manufacturing industry in new century, subst ituting for "Made in U.S.", "Made in Japanese" and "Made in Europe". The Chinese manufacturing industry should hold tightly the opportunity to melt into the wor ldwide recombination and transfer and enter GMN, so as to accomplish leaping dev elopment.
文摘Objective:To assess the association between genetic variants of transferrin receptor 2(TFR2)exon 4 and anemia status and to describe the expression levels of several cytokines,hepcidin,soluble transferrin receptor and erythropoietin.Methods:Institutional based comparative study was done randomly to recruit 106 pregnant women who attended antenatal care in three different health centers in Boyolali Regency,Central Java from May 2015 to September 2015.DNA was extracted from peripheral blood samples of selected pregnant women and sequencing was done for TFR2 exon 4.Furthermore,enzyme-linked immunosorbent assay was conducted to measure the expression levels of interleukin 6,interleukin 4,transforming growth factorβand iron-metabolism related proteins such as hepcidin,soluble transferrin receptor,and erythropoietin.Gene alignment was performed by using a CLUSTAL W program.Collected data were analyzed statistically by using parametric and nonparametric tests with Statistical Product and Service Solutions(SPSS)20.0 for Windows.Results:Three novel genetic variants from TFR2 exon 4(position 603,605 and 606)were associated with anemia status.Moreover,the expression levels of interleukin 6,interleukin 4,transforming growth factorβand erythropoietin were higher in anemic pregnant women than those of nonanemic pregnant women but only erythropoietin level reached statistical significance.These results were followed by decreases of hepcidin and soluble transferrin receptor levels.Conclusions:Various factors contribute to anemia prevalence among pregnant women in Boyoali Regency,Central Java,Indonesia.Our novel findings showed that TFR2 exon 4 has 3 mutational sites in position 603,605 and 606.These novel genetic variants may provide a new insight into the role of TFR2 in anemia.
基金funded by the thousand PhD program of Guangdong Academy of Sciences(No.2018GDASCX-0932,No.2020GDASYL-20200103099)the Training Fund of Guangdong Institute of Applied Biological Resources For PhDs,Masters and Postdoctoral Researchers(No.GIABR-pyjj201603)+2 种基金the GDAS Special Project of Science and Technology Development(No.2018GDASCX-0107)the Scientific and Technological Program of Guangdong Province(No.2017A020219004)the National Natural Science Foundation of China(No.31772486)。
文摘The yellow pond turtle Mauremys mutica is widely cultured using both greenhouse-reared and outdoor pond-reared models.Individuals from the two models often show different tolerances to dramatic temperature changes caused by extreme weather events.However,the mechanism underlying the difference is unclear.In this study,we found that for greenhouse-reared turtles(GRTs),the expression levels of an immune-related gene for transferrin were significantly different(P<0.05)between the control group and the acute cold stress(ACS)group for most time points(3 h,6 h and 48 h),while at two time points(6 h and 12 h)there was a significant difference(P<0.05)between the control group and the acute heat stress(AHS)group.However,for the outdoor pond-reared turtles(OPTs),we found the opposite pattern:the ACS group showed no significant difference(P>0.05)from the control group for all time points(3 h,6 h,12 h,24 h and 48 h),whereas two time points(12 h and 24 h)were significantly different(P<0.05)for the AHS group.Our results indicate that ACS may influence the immunity of GRTs and have no influence on OPTs,whereas AHS may largely affect the immunity of OPTs and have little influence on GRTs.The findings provide insights into the mechanism underlying the different morbidity and mortality rates of turtles from different culture models after extreme weather events.
基金National Natural Science Foundation of China(No.31570937 and No.81871391)Natural Science Foundation of Hubei Province of China(No.2017CFB707)+1 种基金the Fundamental Research Funds for the Central Universities of China(No.HUST:2018KFYYXJJ086)Graduates'Innovation Foundation of Huazhong University of Science and Technology(No.5003510001).
文摘Selecting an ideal molecular format from diverse structures is a major challenge in developing a bispecific antibody(BsAb).To choose an ideal format of anti-CD3 x anti-transferrin receptor(TfR)bispecific antibodies for clinical application,we constructed TfR bispecific T-cell engager(BiTE)in two extensively applied formats,including single-chain tandem singlechain variable fragments(scFvs)and double-chain diabodies,and evaluated their functional characterizations in vitro.Results demonstrated that TfR-BiTE in both formats directed potent killing of TfR+HepG2 cells.However,compared to two・chain diabodies,scFvs were more efficient in antigen binding and TfR target killing.Furthermore,different domain orders in scFvs would also be evaluated because single-TfR-CD3-His was preferable to single-CD3-TfR-His in immunotherapeutic strategies.Thus,the single-chain tandem TfR-CD3 format was favored for further investigation in cancer therapy.
基金Zhongshan Municipal Science and Technology Plan Project(No.2017B1061)
文摘Objective: To investigate the effect of high throughput hemodialysis on soluble transferrin receptor in hemodialysis patients and the improvement of renal anemia. Methods: 132 patients receiving maintenance hemodialysis in our hospital from July 2017 to July 2019 were selected and divided into control group and observation group according to the random number table method, with 66 cases each. The observation group was treated with high-flux hemodialysis, while the control group was treated with low-flux hemodialysis for 6 months. Compare two groups before and after treatment serum beta 2 microglobulin (beta 2 - MG), serum creatinine (Scr), blood urea nitrogen (BUN) level, anemia related index [red blood cells deposited (HCT), hemoglobin (Hb), reticulocyte percentage (Ret%)], iron metabolism index [serum ferritin (SF), transferrin saturation (TSAT)、Hepcidin(Hepc)], soluble transferrin receptor (sTfR) levels and adverse reactions. Results: the levels of 2-MG, Scr and BUN in the two groups before treatment were compared (P>0.05). After treatment, Scr and BUN levels in the two groups were significantly decreased (P<0.05), but were compared between the two groups (P>0.05). The level of 2-MG in the observation group was lower than that in the control group (P<0.05). Before treatment, sTfR, Hb, HCT level and Ret% of the two groups were compared(P>0.05). After treatment, Hb and HCT levels in the observation group were higher than those in the control group, while Ret% were lower than those in the control group, (P<0.05). Before treatment, the levels of ST、TAST、sTfR and Hepc in the two groups were compared (P>0.05). After treatment, the level of ST and TAST in the observation group was higher than that in the control group, The levels of sTfR and Hepc were lower than the control group (P<0.05). The overall incidence of adverse reactions in the observation group (8.93%) was lower than that in the control group (10.14%), with no significant difference (P>0.05). Conclusion: The high-throughput hemodialysis department significantly improved renal anemia in hemodialysis patients, reduced serum sTfR level, and had fewer adverse reactions and higher safety.
文摘Hypochromic microcytic anaemia includes iron deficiency, anaemia of chronic disorders, beta thalassemia trait and sideroblastic anaemia. To rule out the cause of hypochromic microcytic anaemia is a diagnostic difficulty. The conventional laboratory tests used for diagnosis have few disadvantages. Serum transferrin receptor (sTfR) is the most reliable method for assessment of body iron. Eighty four children were included in this study. They were further divided into four groups: iron deficiency anaemia (IDA), anaemia of chronic disorders (ACD), beta thalassemia trait (β TT) and controls. Children withIDAand ACD were diagnosed on the basis of history and serum iron profile. Subjects with β TT had HbA2 > 3.5%. sTfR were performed on all subjects. Level of sTfR in patients withIDAwas 5.79 μg/ml ± 1.3 μg/ml. In patients with anaemia of chronic disorders (ACD), β thalassemia trait and controls mean sTfR were 2.18 μg/ml ± 0.6 μg/ml, 2.1μg/ml ± 0.5 μg/ml and 2.0 μg/ml ± 0.5 μg/ml respectively. These results show level of sTfR was raised in IDA when compared with controls or ACD and β TT (p
文摘Objective: To study the correlation of serum hepcidin (HEP) and transferrin receptor (sTfR) contents with iron deficiency and micro-inflammatory response in patients with hemodialysis. Methods: Patients undergoing maintenance hemodialysis in the Jingzhou Central Hospital between June 2014 and March 2017 were selected as MHD group, healthy volunteers receiving physical examination during the same period were selected as control group, serum was collected to determine the levels of HEP, sTfR, iron deficiency indexes, inflammatory response indexes and oxidative stress indexes, and the correlation between indicators was analyzed. Results: Serum HEP, sTfR, TNF-α, IL-17, IL-23, NOX2 and MDA levels of MHD group were higher than those of control group while SF, TRF, Aeplin, IL-10, SOD, GSH-P and TAC levels were lower than those of control group;serum Aeplin, IL-10, SOD, GSH-P and TAC levels of MHD group were negatively correlated with SF and TRF levels whereas the TNF-α, IL-17, IL-23, NOX2 and MDA levels were positively correlated with SF and TRF levels. Conclusions: The increase of serum HEP and sTfR in patients with hemodialysis can reflect the degree of iron deficiency and is closely related to the degree of micro-inflammatory response.
文摘Objective The present study was designed to explore the correlations between prealbumin(PA),transferrin(TF),handgrip strength and nutrition risk screening tool 2002(NRS 2002),patient-generated subjective global assessment(PG-SGA)in preoperative nutritional screening and evaluation in gastric cancer patients.Methods 132 cases of gastric cancer patients undergoing surgical treatment from May 2015 to January 2018 were screened and evaluated by NRS 2002 and PG-SGA within 48 h after admission,and the PA,TF and handgrip strength were measured for each patient.Results The levels of PA,TF,and handgrip strength in the nutritional risk group(NRS 2002≥3)and the malnutrition group(PG-SGA≥4)were significantly lower than that in non-nutrition risk group(NRS 2002<3)and non-malnutrition group(PG-SGA<4).The levels of PA,TF,and handgrip strength of preoperative patients were negatively correlated with NRS 2002 and PG-SGA scores(P<0.05).NRS 2002 and PG-SGA scores were positively correlated(r=0.712,P<0.01).Conclusion The preoperative nutritional risk and malnutrition rate in patients with gastric cancer are high.The combined application of PA,TF,handgrip strength,NRS 2002,and PG-SGA is more helpful for nutritional screening and assessment in gastric cancer patients.
基金Supported by Natural Key and Basic Research Development Program,No.2002CB513109
文摘AIM: To construct fusion protein of a single-chain antibody(scFv) against transferrin receptor (TfR) with alkalinephosphatase (AP).METHODS: The VH-linker-VL, namely scFv gene, wasprepared by amplifying the VH and VL genes from plasmid pGEM-T-VH and pGEM-T-VL with splicing overlap extension polymerase chain reaction (SOE PCR). After the ScFv gene was modified by SfiⅠ and NotⅠ, it was subcloned into the secretory expression vector pUC19/119, and then was transformed into E. coli TG1. The positive colonies were screened by colony PCR and their expressions were induced by IPTG. ScFv gene was gained by digesting ScFv expression vector pUC19/119 with Sfi I and NotⅠ restriction enzymes, then subcloned into expression vector pDAP2, followed by transformation in E. coli TG1. The positive colonies were selected by bacterial colony PCR. The expression of fusion protein (scFv-AP) was induced by IPTG. Its activity was detected by enzyme immunoassay. The molecular weights of scFv and scFv-AP were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).RESULTS: The product of SOE PCR formed a band of 700 bp in agarose gel electrophoresis. SDS-PAGE demonstrated the molecular weight of scFv was 27 ku. Immunofluorescent assay (IFA) demonstrated its reactivity with TfR. The molecular weight of scFv-AP was 75 ku. Enzyme immunoassay showed that scFv-AP could specifically bind to human TfR and play AP activity.CONCLUSION: We have successfully prepared the antihuman TfR scFv and constructed the fusion protein of scFv and AP. It is promising for immunological experiments.
基金Supported by National Natural Science Foundation of China,No. 81071832the Key Scientific Research Project of the Health Bureau of Hubei Province, No. JX5A01
文摘AIM: To evaluate the sensitivity and specificity of transfesrrin dipstick test (Tf) in colorectal cancer (CRC) screening and precancerous lesions screening. METHODS: Eight hundreds and sixty-one individuals at high-risk for CRC were recruited. Six hundreds and eleven subsequently received the three fecal occult blood tests and colonoscopy with biopsy performed as needed. Fecal samples were obtained on the day before colonoscopy. Tf, immuno fecal occult blood test (IFOBT) and guaiac fecal occult blood test (g-FOBT) were performed simultaneously on the same stool. To minimize false-negative cases, all subjects with negative samples were asked to provide an additional stool specimen for a second test even a third test. If the results were all negative after testing three repeated samples, the subject was considered a true negative. The performance characteristics of Tf for detecting CRC and precancerous lesions were examined and compared to those of IFOBT and the combination of Tf, IFOBT and g-FOBT. RESULTS: A total of six hundreds and eleven subjects met the study criteria including 25 with CRC and 60 with precancerous lesions. Sensitivity for detecting CRC was 92% for Tf and 96% for IFOBT, specificities of Tf and IFOBT were both 72.0% (95% CI: 68.2%-75.5%; χ2 = 0.4, P > 0.05); positive likelihood ratios of those were 3.3 (95% CI: 2.8-3.9) and 3.4 (95% CI: 2.9-4.0), respectively. In precancerous lesions, sensitivities for Tf and IFOBT were 50% and 58%, respectively (χ 2 = 0.8, P > 0.05); specificities of Tf and IFOBT were 71.5% (95% CI: 67.6%-75.1%) and 72.2% (95% CI: 68.4%-75.8%); positive likelihood ratios of those were 1.8 (95% CI: 1.3-2.3) and 2.1 (95% CI: 1.6-2.7), respectively; compared to IFOBT, g-FOBT+ Tf+ IFOBT had a significantly higher positive rate for precancerous lesions (83% vs 58%, respectively; χ 2 = 9.1, P < 0.05). In patients with CRC and precancerous lesions, the sensitivities of Tf and IFOBT were 62% and 69% (χ 2 = 0.9, P > 0.05); specificities of those were 74.5% (95% CI: 70.6%-78.1%) and 75.5% (95% CI: 71.6%-79.0%); positive likelihood ratios of those were 2.5 (95% CI: 2.0-3.1) and 2.8 (95% CI: 2.3-3.5). Compared to IF-OBT alone, combining g-FOBT, IFOBT and Tf led to significantly increased sensitivity for detecting CRC and cancerous lesions (69% vs 88%, respectively; χ 2 = 9.0, P < 0.05). CONCLUSION: Tf dipstick test might be used as an ad- ditional tool for CRC and precancerous lesions screening in a high-risk cohort.
基金funded by the 863 Program entitled as"The research and exploration of nutrition fortified food for improving growth and development(2010AA023004)"performed by the Trace Elements Nutrition Key Laboratory of the Ministry of Health
文摘Objective To establish and evaluate a protein microarray method for combined measurement of serum ferritin(SF) and soluble transferrin receptor(sTfR).Methods Microarrayer was used to print both anti-SF antibodies I and anti-sTfR antibodies I on each protein microarray.Anti-SF antibodies II and anti-sTfR antibodies II were used as detection antibodies and goat antibodies coupled to Cy3 were used as antibodies III.The detection conditions of the quantitative analysis method for simultaneous measurement of SF and sTfR with protein microarray were optimized and evaluated.The protein microarray was compared with commercially available traditional tests with 26 serum samples.Results By comparison experiment,mouse monoclonal antibodies were chosen as the probes and contact printing was chosen as the printing method.The concentrations of SF and sTfR probes were 0.5 mg/mL and 0.5 mg/mL respectively,while those of SF and sTfR detection antibodies were 5 μg/mL and 0.36 μg/mL respectively.Intra-and inter-assay variability was between 3.26% and 18.38% for all tests.The regression coefficients comparing protein microarray with traditional test assays were better than 0.81 for SF and sTfR.Conclusion The present study has established a protein microarray method for combined measurement of SF and sTfR.
基金funded by Shanghai Municipal Health Bureau,No.KPB-WSJ1004the National Natural Science Foundation of China,No.81200971
文摘Iron is an essential trophic element that is required for cell viability and differentiation, especially in oligodendrocytes, which consume relatively high rates of energy to produce myelin. Multiple iron metabolism proteins are expressed in the brain including transferrin receptor and ferritin-H. However, it is still unknown whether they are developmentally regulated in oligodendrocyte lineage cells for myelination. Here, using an in vitro cultured differentiation model of oligodendrocytes, we found that both transferrin receptor and ferritin-H are significantly upregulated during oligodendrocyte maturation, implying the essential role of iron in the development of oligodendrocytes. Additional different doses of Fe3+ in the cultured medium did not affect oligodendrocyte precursor cell maturation or ferritin-H expression but decreased the expression of the transferrin receptor. These results indicate that upregulation of both transferrin receptor and ferritin-H contributes to maturation and myelination of oligodendrocyte precursor cells.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,No.2015R1D1A1A01059980partially supported by the Research Institute for Veterinary Science,Seoul National University
文摘In the present study, we used immunohistochemistry and western blot analysis to examine changes in the levels and cellular localization of iron, heavy chain ferritin(ferritin-H), and transferrin in the gerbil hippocampal CA1 region from 30 minutes to 7 days following transient forebrain ischemia. Relative to sham controls, iron reactivity increased significantly in the stratum pyramidale and stratum oriens at 12 hours following ischemic insult, transiently decreased at 1–2 days and then increased once again within the CA1 region at 4–7 days after ischemia. One day after ischemia, ferritin-H immunoreactivity increased significantly in the stratum pyramidale and decreased at 2 days. At 4–7 days after ischemia, ferritin-H immunoreactivity in the glial components in the CA1 region was significantly increased. Transferrin immunoreactivity was increased significantly in the stratum pyramidale at 12 hours, peaked at 1 day, and then decreased significantly at 2 days after ischemia. Seven days after ischemia, Transferrin immunoreactivity in the glial cells of the stratum oriens and radiatum was significantly increased. Western blot analyses supported these results, demonstrating that compared to sham controls, ferritin H and transferrin protein levels in hippocampal homogenates significantly increased at 1 day after ischemia, peaked at 4 days and then decreased. These results suggest that iron overload-induced oxidative stress is most prominent at 12 hours after ischemia in the stratum pyramidale, suggesting that this time window may be the optimal period for therapeutic intervention to protect neurons from ischemia-induced death.
基金National Natural Science Foundation of China(No.30470372Foundation of Xiamen Natural Science of China(No.3502Z2001262)Program for Innovative Research Team in Science and Technology in Fujian Province University
文摘Transferrin(TF) and its isoforms have been widely reported via various analytical techniques, including a noticeable increased number of isoforms with low content of sialic acid(asialo-, monosialo-, and disialo-transferrin) and asialo-TF as well as disialo-TF, with one or several oligosaccharides released in human serum transferrin(hTf). Here, hTf has been purified by native gradient polyacrylamide gel electrophoresis(PAGENG) before use. The hTf extracted with the electron-transfer approach showed a single subunit band(77.1 Da) in the SDS-PAGE gel, but it exhibited two bands in the native and denatured isoelectric focusing(IEF) gels, namely, hTf-2Fe3+ and apo-hTf, without finding any other transferrin isoforms. A reversed phase HPLC(RP-HPLC) equipped with a C18 column effectively separated hTf and its polymers and combined off-line techniques, including peptide mass fingerprinting(PMF), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS) and database search, and identified the high homology among hTf, apo-hTf, and their isoforms. Moreover, the elution solution consisting of acetonitrile and formic acid could easily denature both hTf and apo-hTf to form various isoforms during separation with HPLC, indicating that chemical factors lead to the formation of various isoforms in transferrin, artificially, during extraction and separation. The authors claimed that only two transferrin isoforms existed in the NHS, namely, hTf-2Fe3+ and apo-hTf, which could be employed in biomarkers, to distinguish the healthy population from many disease sufferers, such as, carbohydrate-deficient transferrin(CDT).
文摘The work described the synthesis and evaluation of PEI–g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5 (mol/mol). The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.
