Chemical insecticides targeting the digestive system of diamondback moth(DBM),Plutella xylostella,have not been developed.The discovery of an insecticide with novel mode of action is a challenge for the control of DBM...Chemical insecticides targeting the digestive system of diamondback moth(DBM),Plutella xylostella,have not been developed.The discovery of an insecticide with novel mode of action is a challenge for the control of DBM.In this study,a class of selenium-and difluoromethyl-modified azoles(fluoroazole selenoureas,FASU)were designed and synthesized for the control of DBM.Of these azoles,compound B4 showed the highest insecticidal activity against DBM.The LC50of third-and second-instar larvae reached 32.3 and 4.6μg mL^(–1),respectively.The midgut tissue of larvae was severely disrupted,and the larval intestinal tissue was dotted with unique red spots after treatment with compound B4.Compound B4 led to disintegration of the peritrophic matrix,swelling of the midgut epithelium,fracture of the microvilli,and extensive leakage of cellular debris in the midgut lumen.Surviving larvae grew very slowly,and the larval duration was significantly prolonged after exposure to compound B4 at sublethal doses(LC10,LC25and LC50).Furthermore,the pupation rate,emergence rate and pupae weight were significantly decreased.Compound B4 also induced abnormal pupae,causing adults to be trapped in the cocoon or failure to fly due to twisted wings.These results demonstrated that FASU could reduce the population of DBM in sublethal doses.FASU is the first synthetic insecticidal lead compound that has been shown to disrupt the midgut tissue of the larvae of DBM,and its mode of action totally differs from that of commercial chemical insecticides.展开更多
Midgut juice plays an important role in food digestion and detoxification in insects.In order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic ac...Midgut juice plays an important role in food digestion and detoxification in insects.In order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic activity of midgut juice and its degradation of Bt proteins(Cry2A,Cry1C,Cry1Aa,and Cry1Ac)were evaluated in this study through protease inhibitor treatments.The activities of total protease in midgut juices were significantly inhibited by phenylmethylsulfonyl fluoride(PMSF),tosyl-L-lysine chloromethyl ketone(TLCK),pepstatin A and leupeptin.The enzymatic activity of chymotrypsin was significantly inhibited by PMSF,and enzymatic activity of trypsin was significantly inhibited by ethylenediaminetetraacetic acid(EDTA),PMSF,tosyl phenylalanine chloromethyl ketone(TPCK),TLCK and trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane(E-64).EDTA could significantly inhibit the degradation of Cry2A by C.medinalis.EDTA,PMSF,TPCK,and TLCK could inhibit the degradation of Cry1C and Cry1Aa.EDTA,PMSF,TPCK,TLCK,and E-64 could inhibit the degradation of Cry1Ac.Our results indicated that some protease inhibitors hindered various enzymatic activities in the larval midgut of C.medinalis,which may reduce the insect’s ability to degrade Bt toxins.These findings may aid the application of protease inhibitors in the management of this insect pest in the future.展开更多
BACKGROUND Reverse rotation of the midgut is a rare type of intestinal malrotation.Volvulus of the right colon or entire midgut,stenosis of the transverse colon and obstruction of the duodenojejunal junction are commo...BACKGROUND Reverse rotation of the midgut is a rare type of intestinal malrotation.Volvulus of the right colon or entire midgut,stenosis of the transverse colon and obstruction of the duodenojejunal junction are common complications of reverse rotation.In this study,we report the first case of intestinal obstruction associated with reverse rotation in pregnancy.CASE SUMMARY A 31-year-old woman at 362+wk gestation presented to the emergency department with progressive abdominal cramping,nausea and bilious vomiting.Abdominal ultrasound scanning showed dilatation of the bowel.Computed tomography scanning revealed features of reverse rotation of the midgut with intestinal volvulus.After consultation with the obstetrician,the pregnancy was terminated and exploratory abdominal surgery was performed.Intra-operatively,it was found that the mesentery of the colon and small intestine was insufficiently attached.The right colon and the small intestinal mesentery was twisted,and intestinal necrosis was observed.The duodenum and duodenojejunal junction were curved in front of the transverse colon,and the transverse colon passed through the tunnel behind the mesenteric root.Intestinal reverse rotation with volvulus was confirmed.The necrotic intestine was resected and small intestine mesenteric reconstruction was performed.The patient recovered after surgery.After leaving the hospital,the patient and her daughter remained well during an 8-month follow-up period.CONCLUSION We report the diagnosis,treatment and etiology of a pregnant patient with intestinal obstruction due to reverse rotation of the midgut.For similar cases,appropriate diagnosis and treatment should be carried out according to the condition of the fetus and pregnant woman.展开更多
Midgut volvulus is a clinical rare condition which appears as recurrent intermittent abdominal pain after consumption of food with intermittent colicky pain and sometimes with completely asymptomatic period. This gut ...Midgut volvulus is a clinical rare condition which appears as recurrent intermittent abdominal pain after consumption of food with intermittent colicky pain and sometimes with completely asymptomatic period. This gut twist may result in complications such as ischemia, obstruction, hemorrhage, or perforation. In the yolk sac during the third week of intrauterine life, there is normal communication with intraembryonic gut. During development proceeds, this communication gets thinner into a tube known as the vitellointestinal duct. Vitellointestinal duct usually becomes obliterated before eighth week of intrauterine life. In about 2% of people this duct persists and gives rise to a group of anomalies such as Meckel’s diverticulum is the commonest and complete patency of the duct is the rarest. Here we present the case of a 34-year-old male who presented with both conditions.展开更多
Fetal midgut volvulus is quite rare, and most cases are associated with abnormalities of intestinal rotation or fixation. We report a case of midgut volvulus without malrotation, associated with a meconium pellet, dur...Fetal midgut volvulus is quite rare, and most cases are associated with abnormalities of intestinal rotation or fixation. We report a case of midgut volvulus without malrotation, associated with a meconium pellet, during the gestation period. This 2.79 kg, 33-wk infant was born via a spontaneous vaginal delivery caused by preterm labor. Prenatal ultrasound showed dilated bowel loops with the appearance of a 'coffee bean sign'. This patient had an unusual presentation with a distended abdomen showing skin discoloration. An emergency laparotomy revealed a midgut volvulus and a twisted small bowel, caused by complicated meconium ileus. Such nonspecific prenatal radiological signs and a low index of suspicion of a volvulus during gestation might delay appropriate surgical management and result in ischemic necrosis of the bowel. Preterm labor, specific prenatal sonographic findings (for example, the coffee bean sign) and bluish discoloration of the abdominal wall could suggest intrauterine midgut volvulus requiring prompt surgical intervention.展开更多
Xenorhabdus nematophila HB310, which is highly virulent for many insects, is symbiotic with Steinernema carpocapsae HB310. Toxin Ⅱ was obtained using methods such as salting out and native-PAGE from the cells of X. n...Xenorhabdus nematophila HB310, which is highly virulent for many insects, is symbiotic with Steinernema carpocapsae HB310. Toxin Ⅱ was obtained using methods such as salting out and native-PAGE from the cells of X. nematophila HB310. The histopathology of toxin Ⅱ on H. armigera larvae was studied by dissecting an olefin slice of the midgut. The symptoms showed that the histopathology of the H. armigera midgut was similar to that of other novel midgut-active toxins such as the δ-endotoxins from Bacillus thuringiensis, as well as Tca from Photorhabdus luminescens W14. The midgut tissues of H. armigera fourth-instar larvae began to transform after the oral intake of the toxin Ⅱ over 6 h. First, the anterior region of the peritrophic membrane (PM) began to degrade followed by the elongation of the columnar cells. The epithelium decomposed gradually, and the midgut tissues were either loose or disordered. The PM disappeared after 12 h but reappeared after 72 h following transient or sublethal exposure to the toxin Ⅱ. Toxin Ⅱ also directly destroyed in vitro PMs of H. armigera.展开更多
Jejunal diverticulosis is uncommon and often asymptomatic.It can produce significant complications,and some complications are potentially life threatening and require early surgical treatment,such as obstruction,hemor...Jejunal diverticulosis is uncommon and often asymptomatic.It can produce significant complications,and some complications are potentially life threatening and require early surgical treatment,such as obstruction,hemorrhage and perforation.There is no consensus on the management of this disease.Only a few cases of jejunal diverticulosis with midgut volvulus have been reported.We herein report a case of 57-year-old woman with jejunal diverticulosis causing small bowel volvulus who complained of intermittent upper abdominal pin-prick for 5 years that eventually progressed to a complete obstruction.The computed tomography scans revealed a mesenteric vessel "whirlpool" and laparotomy showed midgut volvulus secondary to jejunal diverticula.This case highlights jejunal diverticulosis causing small bowel volvulus as an uncommon mechanism of small bowel obstruction,which should be included in the differential diagnosis of small bowel obstruction.展开更多
This study was to discuss the relationship among the change in the activity of Bombyx mori carboxylesterase (BmCarE) in the midguts, the differential expression of BmCarE gene (bmcare) in the midguts, and the ability ...This study was to discuss the relationship among the change in the activity of Bombyx mori carboxylesterase (BmCarE) in the midguts, the differential expression of BmCarE gene (bmcare) in the midguts, and the ability of Bombyx mori resistant to densonucleosis virus (BmDNV), and to elucidate the molecular mechanism of resistance to BmDNV-Z. With two silkworm strains, HUABA, which is susceptible to BmDNV-Z, and BC8 (a near isogenic line of HUABA), which is completely resistant to the same virus, as materials, the activity of BmCarE in the midgut was determined by Bio-Tek Synergy, and the differential expression of bmcare between the two strains was investigated by real-time fluorescence quantitative PCR, both at 12, 36, and 72 h post oral inoculation of the two strains with virus (hereafter referred as inoculation). While the activity of BmCarE in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculated group, and the HUABA control group by 3.28, 2.26, and 3.02 times, respectively, with the difference being highly significant (P < 0.01), there was no statistical difference among the other groups. The relative expression level of bmcare in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculation group, and the HUABA control group by 17.714, 21.76, and 15.09 times, respectively, with the difference being highly significant (P < 0.01), and there was no statistical difference among other groups. The elevation of BmCarE activity and expression level of bmcare in the resistant strain at 12 h post inoculation may relate to the resistant gene (nsd/nsd) and the stimulation of BmDNV-Z. The molecular basis for the elevation of BmCarE activity in the resistant strain BC8 may be the change in the expression level of bmcare.展开更多
Ixodid ticks play an important role in the transmission of a variety of zoonoses of viral, bacterial and protozoan origin, and they also harbor a wealth of microorganisms. To gain more detailed insights into the poten...Ixodid ticks play an important role in the transmission of a variety of zoonoses of viral, bacterial and protozoan origin, and they also harbor a wealth of microorganisms. To gain more detailed insights into the potential interactions between bacterial flora and tick-borne pathogens, we investigated the midgut bacterial flora of laboratory-reared Haemaphysalis longicornis, Hyalomma asiaticum and Rhipicephalus haemaphysaloides. Based on morphological, biochemical, and 16 S rDNA sequencing results, we identified 15 species belonging to 12 genera in the midgut of the three ticks. The bacterial communities were similar to those found in other studies of hematophagous arthropods. Kocuria sp. was the most frequently isolated species and its 16 S rDNA gene sequence was very similar to Kocuria koreensis P31 T. To our knowledge, this is the first report of the bacterial flora of tick midguts and the results show that there were many different bacterial species in each tick species. Among the most common genera, there may have been a novel species in the genus Kocuria. The results might be the first step for looking for different aspects of the pathogen and tick interaction.展开更多
It was controversial issue if nuclear polyhedrosis virus(NPV) could replicate in midgut cells of host larvae from Lepidoptera by now.The replication of Mythimna separata NPV(MsNPV) in M.separata larvae midgut ...It was controversial issue if nuclear polyhedrosis virus(NPV) could replicate in midgut cells of host larvae from Lepidoptera by now.The replication of Mythimna separata NPV(MsNPV) in M.separata larvae midgut cells was studied by ultrastructural and DNA hybridized techniques.The paper demonstrated that the MsNPV could neither infect midgut cell nor replicate in midgut cell of homologous host.Therefore MsNPV virions released from the virial occlusion bodies were considered as direct penetration though the intercellular spaces of midgut cells to hemocoel of the host larvae.展开更多
Low-density lipoprotein receptor-related protein 2(LRP2)is a multifunctional endocytic receptor expressed in epithelial cells.In mammals,it acts as an endocytic receptor that mediates the cellular uptake of cholestero...Low-density lipoprotein receptor-related protein 2(LRP2)is a multifunctional endocytic receptor expressed in epithelial cells.In mammals,it acts as an endocytic receptor that mediates the cellular uptake of cholesterol-containing apolipoproteins to maintain lipid homeostasis.However,little is known about the role of LRP2 in lipid homeostasis in insects.In the present study,we investigated the function of LRP2 in the migratory locust Locusta migratoria(LmLRP2).The mRNA of LmLRP2 is widely distributed in various tissues,including integument,wing pads,foregut,midgut,hindgut,Malpighian tubules and fat body,and the amounts of LmLRP2 transcripts decreased gradually in the early stages and then increased in the late stages before ecdysis during the nymphal developmental stage.Fluorescence immunohistochemistry revealed that the LmLRP2 protein is mainly located in cellular membranes of the midgut and hindgut.Using RNAi to silence LmLRP2 caused molting defects in nymphs(more than 60%),and the neutral lipid was found to accumulate in the midgut and surface of the integument,but not in the fat body,of dsLmLRP2-treated nymphs.The results of a lipidomics analysis showed that the main components of lipids(diglyceride and triglyceride)were significantly increased in the midgut,but decreased in the fat body and hemolymph.Furthermore,the content of total triglyceride was significantly increased in the midgut,but markedly decreased in the fat body and hemolymph in dsLmLRP2-injected nymphs.Our results indicate that LmLRP2 is located in the cellular membranes of midgut cells,and is required for lipid export from the midgut to the hemolymphand fat body in locusts.展开更多
Metamorphosis is one of the most important physiological processes in insects.It is regulated by a serial of ecdysone cascade genes.Recently,lots o f microRNAs(miRNAs)were investigated in insects;however,their functio...Metamorphosis is one of the most important physiological processes in insects.It is regulated by a serial of ecdysone cascade genes.Recently,lots o f microRNAs(miRNAs)were investigated in insects;however,their function in metamorphosis is largely unknown.In the present study,the dynamics of a small RNA population was investigated by RNA sequencing from the midgut of a lepidopteran pest Spodoptera litura during larval-pupal metamorphosis.A total of 101 miRNAs were identified,and 75 miRNAs were differentially expressed during the metamorphic process.The relationship between these differentially expressed miRNAs and 12 ecdysone cascade genes was analyzed by four classical software programs,and a multiple-to-multiple regulatory network was found to exist between these miRNAs and their targets.Among them,miR-14-3p and its two targets(EcR and E75)were chosen for further validation.MiR-14-3p had higher expression level in the 6 th instar larvae as compared with either the prepupae or pupae,which was opposite to that of both EcR and E75,two ecdysone cascade genes.Luciferase reporter assay confirmed that both EcR and E75 were regulated by miR-14-3p.Interestingly,the 3'untranslated regions are nearly identical to each other among different transcript variants of the ecdysone cascade genes,including EcR,USP,E75,E74,E78,E93,Hr3,Hr4,Hr39,K rhl and F tzfl.Thus,different transcript variants of one ecdysone cascade gene could be regulated by the same mi RNA.The above data suggest that the ecdysone signaling pathway is under the tight control of miRNA.These findings expand our understanding of the mechanism of insect metamorphosis and may also provide a novel possibility for the control of pest insects in the future.展开更多
The insect midgut epithelium is composed of columnar, goblet, and regenerative cells. Columnar epithelial cells are the most abundant and have membrane protrusions that form the brush border membrane (BBM) on their ap...The insect midgut epithelium is composed of columnar, goblet, and regenerative cells. Columnar epithelial cells are the most abundant and have membrane protrusions that form the brush border membrane (BBM) on their apical side. These increase surface area available for the transport of nutrients, but also provide opportunities for interaction with xenobiotics such as pathogens, toxins and host plant allelochemicals. Recent improvements in proteomic and bioinfbrmatics tools provided an opportunity to determine the proteome of the T. ni BBM in unprecedented detail. This study reports the identification of proteins from BBM vesicles (BBMVs) using single dimension polyacrylamide gel elec? trophoresis coupled with multi-dimensional protein identification technology. More than 3000 proteins were associated with the BBMV of which 697 were predicted to possess either a signal peptide, at least one transmembrane domain or a GPI-anchor signal. Of these, bioinfbrmatics analysis and manual curation predicted that 185 may be associated with the BBMV or epithelial cell plasma membrane. These are discussed with respect to their predicted functions, namely digestion, nutrient uptake, cell signaling, development, cell-cell interactions, and other functions. We believe this to be the most detailed proteomic analysis of the lepidopteran midgut epithelium membrane to date, which will provide information to better understand the biochemical, physiological and pathological processes taking place in the larval midgut.展开更多
Bombyx mori nucleopolyhedrovirus(BmNPV)is a DNA virus that causes huge losses to the silkworm industry but the piRNA responses during BmNPV infection in the silkworm remain uninvestigated.Here,silkworm piRNA profiles ...Bombyx mori nucleopolyhedrovirus(BmNPV)is a DNA virus that causes huge losses to the silkworm industry but the piRNA responses during BmNPV infection in the silkworm remain uninvestigated.Here,silkworm piRNA profiles of uninfected and BmNPV-infected fat body and midgut were determined by high-through sequencing in the early stages of BmNPV infection.A total of 2675 and 3396 genome-derived piRNAs were identified from fat body and midgut,respectively.These genome-derived piRNAs mainly originated from unannotated instead of transposon regions in the silkworm genome.In total,572 piRNAs were associated with 280 putative target genes in fat body and 805 piRNAs with 380 target genes in midgut.Compared to uninfected tissues,322 and 129 piRNAs were significantly upregulated in BmNPV-infected fat body and midgut,respectively.In addition,276 and 117 piRNAs were significantly downregulated.Moreover,differentially expressed(DE)piRNAs during BmNPV infection differed significantly between fat body and midgut.Putative DE piRNA-targeted genes were associated with“response to stimulus”and“environmental information processing”in fat body after infection with BmNPV,which may indicate an active piRNA response to BmNPV infection in fat body.This study may lay the foundation for future research of the potential roles of the piRNA pathway and specific piRNAs in BmNPV pathogenesis.展开更多
Spodoptera litura is a destructive agricultural pest in tropical and subtropical areas.Understanding the molecular mechanisms of S.litura adaptation to its preferred host plants may help identify target genes useful f...Spodoptera litura is a destructive agricultural pest in tropical and subtropical areas.Understanding the molecular mechanisms of S.litura adaptation to its preferred host plants may help identify target genes useful for pest control.We used high-throughput sequencing to characterize the expression patterns of messenger RNAs(mRNAs)and microRNAs(miRNAs)in the midgut of S.litura fed on Brassica juncea for 6 h and 48 h.A total of 108 known and 134 novel miRNAs were identified,29 miRNAs and 237 mRNAs were differentially expressed at 6 h of B.juncea feeding,26 miRNAs and 433 mRNAs were differentially expressed at 48 h.For the mRNAs,the up-regulated genes were mostly enriched in detoxification enzymes(cytochrome P450,esterase,glutathione^-transferase,uridine diphosphate-glucuronosyl transferase),while the down-regulated genes were mostly enriched in proteinases and immune-related genes.Furthermore,most detoxification enzymes begin to up-regulate at 6 h,while most digestion and immunerelated genes begin to up-or down-regulate at 48 h.Eighteen and 37 differently expressed transcription factors were identified at 6 h and 48 h,which may regulate the functional genes.We acquired 136 and 41 miRNA versus mRNA pairs at 6 h and 48 h,respectively.Some down-regulated and up-regulated miRNAs were predicted to target detoxification enzymes and proteinases,respectively.Real-time quantitative polymerase chain reaction of nine randomly selected miRNAs and 28 genes confirmed the results of RNA-seq.This analyses of miRNA and mRNA transcriptomes provides useful information about the molecular mechanisms of S.litura response to B.juncea.展开更多
基金financially supported by funding from the Guangdong Basic and Applied Basic Research Foundation,China(2019B151502052)the Program of Science and Technology of Guangzhou,China(202002030295)。
文摘Chemical insecticides targeting the digestive system of diamondback moth(DBM),Plutella xylostella,have not been developed.The discovery of an insecticide with novel mode of action is a challenge for the control of DBM.In this study,a class of selenium-and difluoromethyl-modified azoles(fluoroazole selenoureas,FASU)were designed and synthesized for the control of DBM.Of these azoles,compound B4 showed the highest insecticidal activity against DBM.The LC50of third-and second-instar larvae reached 32.3 and 4.6μg mL^(–1),respectively.The midgut tissue of larvae was severely disrupted,and the larval intestinal tissue was dotted with unique red spots after treatment with compound B4.Compound B4 led to disintegration of the peritrophic matrix,swelling of the midgut epithelium,fracture of the microvilli,and extensive leakage of cellular debris in the midgut lumen.Surviving larvae grew very slowly,and the larval duration was significantly prolonged after exposure to compound B4 at sublethal doses(LC10,LC25and LC50).Furthermore,the pupation rate,emergence rate and pupae weight were significantly decreased.Compound B4 also induced abnormal pupae,causing adults to be trapped in the cocoon or failure to fly due to twisted wings.These results demonstrated that FASU could reduce the population of DBM in sublethal doses.FASU is the first synthetic insecticidal lead compound that has been shown to disrupt the midgut tissue of the larvae of DBM,and its mode of action totally differs from that of commercial chemical insecticides.
基金This study was supported by the Zhejiang Provincial Natural Science Foundation of China(LY20C140004)the National Science and Technology Major Project of China(2016ZX08001001)+1 种基金the National Natural Science Foundation of China(31501669)the earmarked fund for China Agriculture Research System(CARS-01-36).
文摘Midgut juice plays an important role in food digestion and detoxification in insects.In order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic activity of midgut juice and its degradation of Bt proteins(Cry2A,Cry1C,Cry1Aa,and Cry1Ac)were evaluated in this study through protease inhibitor treatments.The activities of total protease in midgut juices were significantly inhibited by phenylmethylsulfonyl fluoride(PMSF),tosyl-L-lysine chloromethyl ketone(TLCK),pepstatin A and leupeptin.The enzymatic activity of chymotrypsin was significantly inhibited by PMSF,and enzymatic activity of trypsin was significantly inhibited by ethylenediaminetetraacetic acid(EDTA),PMSF,tosyl phenylalanine chloromethyl ketone(TPCK),TLCK and trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane(E-64).EDTA could significantly inhibit the degradation of Cry2A by C.medinalis.EDTA,PMSF,TPCK,and TLCK could inhibit the degradation of Cry1C and Cry1Aa.EDTA,PMSF,TPCK,TLCK,and E-64 could inhibit the degradation of Cry1Ac.Our results indicated that some protease inhibitors hindered various enzymatic activities in the larval midgut of C.medinalis,which may reduce the insect’s ability to degrade Bt toxins.These findings may aid the application of protease inhibitors in the management of this insect pest in the future.
文摘BACKGROUND Reverse rotation of the midgut is a rare type of intestinal malrotation.Volvulus of the right colon or entire midgut,stenosis of the transverse colon and obstruction of the duodenojejunal junction are common complications of reverse rotation.In this study,we report the first case of intestinal obstruction associated with reverse rotation in pregnancy.CASE SUMMARY A 31-year-old woman at 362+wk gestation presented to the emergency department with progressive abdominal cramping,nausea and bilious vomiting.Abdominal ultrasound scanning showed dilatation of the bowel.Computed tomography scanning revealed features of reverse rotation of the midgut with intestinal volvulus.After consultation with the obstetrician,the pregnancy was terminated and exploratory abdominal surgery was performed.Intra-operatively,it was found that the mesentery of the colon and small intestine was insufficiently attached.The right colon and the small intestinal mesentery was twisted,and intestinal necrosis was observed.The duodenum and duodenojejunal junction were curved in front of the transverse colon,and the transverse colon passed through the tunnel behind the mesenteric root.Intestinal reverse rotation with volvulus was confirmed.The necrotic intestine was resected and small intestine mesenteric reconstruction was performed.The patient recovered after surgery.After leaving the hospital,the patient and her daughter remained well during an 8-month follow-up period.CONCLUSION We report the diagnosis,treatment and etiology of a pregnant patient with intestinal obstruction due to reverse rotation of the midgut.For similar cases,appropriate diagnosis and treatment should be carried out according to the condition of the fetus and pregnant woman.
文摘Midgut volvulus is a clinical rare condition which appears as recurrent intermittent abdominal pain after consumption of food with intermittent colicky pain and sometimes with completely asymptomatic period. This gut twist may result in complications such as ischemia, obstruction, hemorrhage, or perforation. In the yolk sac during the third week of intrauterine life, there is normal communication with intraembryonic gut. During development proceeds, this communication gets thinner into a tube known as the vitellointestinal duct. Vitellointestinal duct usually becomes obliterated before eighth week of intrauterine life. In about 2% of people this duct persists and gives rise to a group of anomalies such as Meckel’s diverticulum is the commonest and complete patency of the duct is the rarest. Here we present the case of a 34-year-old male who presented with both conditions.
文摘Fetal midgut volvulus is quite rare, and most cases are associated with abnormalities of intestinal rotation or fixation. We report a case of midgut volvulus without malrotation, associated with a meconium pellet, during the gestation period. This 2.79 kg, 33-wk infant was born via a spontaneous vaginal delivery caused by preterm labor. Prenatal ultrasound showed dilated bowel loops with the appearance of a 'coffee bean sign'. This patient had an unusual presentation with a distended abdomen showing skin discoloration. An emergency laparotomy revealed a midgut volvulus and a twisted small bowel, caused by complicated meconium ileus. Such nonspecific prenatal radiological signs and a low index of suspicion of a volvulus during gestation might delay appropriate surgical management and result in ischemic necrosis of the bowel. Preterm labor, specific prenatal sonographic findings (for example, the coffee bean sign) and bluish discoloration of the abdominal wall could suggest intrauterine midgut volvulus requiring prompt surgical intervention.
文摘Xenorhabdus nematophila HB310, which is highly virulent for many insects, is symbiotic with Steinernema carpocapsae HB310. Toxin Ⅱ was obtained using methods such as salting out and native-PAGE from the cells of X. nematophila HB310. The histopathology of toxin Ⅱ on H. armigera larvae was studied by dissecting an olefin slice of the midgut. The symptoms showed that the histopathology of the H. armigera midgut was similar to that of other novel midgut-active toxins such as the δ-endotoxins from Bacillus thuringiensis, as well as Tca from Photorhabdus luminescens W14. The midgut tissues of H. armigera fourth-instar larvae began to transform after the oral intake of the toxin Ⅱ over 6 h. First, the anterior region of the peritrophic membrane (PM) began to degrade followed by the elongation of the columnar cells. The epithelium decomposed gradually, and the midgut tissues were either loose or disordered. The PM disappeared after 12 h but reappeared after 72 h following transient or sublethal exposure to the toxin Ⅱ. Toxin Ⅱ also directly destroyed in vitro PMs of H. armigera.
文摘Jejunal diverticulosis is uncommon and often asymptomatic.It can produce significant complications,and some complications are potentially life threatening and require early surgical treatment,such as obstruction,hemorrhage and perforation.There is no consensus on the management of this disease.Only a few cases of jejunal diverticulosis with midgut volvulus have been reported.We herein report a case of 57-year-old woman with jejunal diverticulosis causing small bowel volvulus who complained of intermittent upper abdominal pin-prick for 5 years that eventually progressed to a complete obstruction.The computed tomography scans revealed a mesenteric vessel "whirlpool" and laparotomy showed midgut volvulus secondary to jejunal diverticula.This case highlights jejunal diverticulosis causing small bowel volvulus as an uncommon mechanism of small bowel obstruction,which should be included in the differential diagnosis of small bowel obstruction.
基金This work was supported by High Technology Research and Development Program of China （2005CB121000） Natural Science Foundation of Jiangsu Province, China （BK2006074）.
文摘This study was to discuss the relationship among the change in the activity of Bombyx mori carboxylesterase (BmCarE) in the midguts, the differential expression of BmCarE gene (bmcare) in the midguts, and the ability of Bombyx mori resistant to densonucleosis virus (BmDNV), and to elucidate the molecular mechanism of resistance to BmDNV-Z. With two silkworm strains, HUABA, which is susceptible to BmDNV-Z, and BC8 (a near isogenic line of HUABA), which is completely resistant to the same virus, as materials, the activity of BmCarE in the midgut was determined by Bio-Tek Synergy, and the differential expression of bmcare between the two strains was investigated by real-time fluorescence quantitative PCR, both at 12, 36, and 72 h post oral inoculation of the two strains with virus (hereafter referred as inoculation). While the activity of BmCarE in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculated group, and the HUABA control group by 3.28, 2.26, and 3.02 times, respectively, with the difference being highly significant (P < 0.01), there was no statistical difference among the other groups. The relative expression level of bmcare in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculation group, and the HUABA control group by 17.714, 21.76, and 15.09 times, respectively, with the difference being highly significant (P < 0.01), and there was no statistical difference among other groups. The elevation of BmCarE activity and expression level of bmcare in the resistant strain at 12 h post inoculation may relate to the resistant gene (nsd/nsd) and the stimulation of BmDNV-Z. The molecular basis for the elevation of BmCarE activity in the resistant strain BC8 may be the change in the expression level of bmcare.
基金supported by grants from the Special Fund for National Commonweal Institute of China (2012JB12)
文摘Ixodid ticks play an important role in the transmission of a variety of zoonoses of viral, bacterial and protozoan origin, and they also harbor a wealth of microorganisms. To gain more detailed insights into the potential interactions between bacterial flora and tick-borne pathogens, we investigated the midgut bacterial flora of laboratory-reared Haemaphysalis longicornis, Hyalomma asiaticum and Rhipicephalus haemaphysaloides. Based on morphological, biochemical, and 16 S rDNA sequencing results, we identified 15 species belonging to 12 genera in the midgut of the three ticks. The bacterial communities were similar to those found in other studies of hematophagous arthropods. Kocuria sp. was the most frequently isolated species and its 16 S rDNA gene sequence was very similar to Kocuria koreensis P31 T. To our knowledge, this is the first report of the bacterial flora of tick midguts and the results show that there were many different bacterial species in each tick species. Among the most common genera, there may have been a novel species in the genus Kocuria. The results might be the first step for looking for different aspects of the pathogen and tick interaction.
基金The project is supported by natural science foundation of Hebei province 39916 9and H ebeiAgricultural University(9816 )
文摘It was controversial issue if nuclear polyhedrosis virus(NPV) could replicate in midgut cells of host larvae from Lepidoptera by now.The replication of Mythimna separata NPV(MsNPV) in M.separata larvae midgut cells was studied by ultrastructural and DNA hybridized techniques.The paper demonstrated that the MsNPV could neither infect midgut cell nor replicate in midgut cell of homologous host.Therefore MsNPV virions released from the virial occlusion bodies were considered as direct penetration though the intercellular spaces of midgut cells to hemocoel of the host larvae.
基金supported by the National Key R&D Program of China (2022YFE0196200)the National Natural Science Foundation of China–Deutsche Forschungsgemeinschaft of Germany (31761133021)+3 种基金the National Natural Science Foundation of China (31970469 and 31701794)the earmarked fund for Modern Agro-industry Technology Research System, China (2023CYJSTX01-20)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi, China (2017104)the Fund for Shanxi “1331 Project”, China
文摘Low-density lipoprotein receptor-related protein 2(LRP2)is a multifunctional endocytic receptor expressed in epithelial cells.In mammals,it acts as an endocytic receptor that mediates the cellular uptake of cholesterol-containing apolipoproteins to maintain lipid homeostasis.However,little is known about the role of LRP2 in lipid homeostasis in insects.In the present study,we investigated the function of LRP2 in the migratory locust Locusta migratoria(LmLRP2).The mRNA of LmLRP2 is widely distributed in various tissues,including integument,wing pads,foregut,midgut,hindgut,Malpighian tubules and fat body,and the amounts of LmLRP2 transcripts decreased gradually in the early stages and then increased in the late stages before ecdysis during the nymphal developmental stage.Fluorescence immunohistochemistry revealed that the LmLRP2 protein is mainly located in cellular membranes of the midgut and hindgut.Using RNAi to silence LmLRP2 caused molting defects in nymphs(more than 60%),and the neutral lipid was found to accumulate in the midgut and surface of the integument,but not in the fat body,of dsLmLRP2-treated nymphs.The results of a lipidomics analysis showed that the main components of lipids(diglyceride and triglyceride)were significantly increased in the midgut,but decreased in the fat body and hemolymph.Furthermore,the content of total triglyceride was significantly increased in the midgut,but markedly decreased in the fat body and hemolymph in dsLmLRP2-injected nymphs.Our results indicate that LmLRP2 is located in the cellular membranes of midgut cells,and is required for lipid export from the midgut to the hemolymphand fat body in locusts.
基金grants from the National Natural Science Foundation of China(Grant No.31672357 and 31872285)。
文摘Metamorphosis is one of the most important physiological processes in insects.It is regulated by a serial of ecdysone cascade genes.Recently,lots o f microRNAs(miRNAs)were investigated in insects;however,their function in metamorphosis is largely unknown.In the present study,the dynamics of a small RNA population was investigated by RNA sequencing from the midgut of a lepidopteran pest Spodoptera litura during larval-pupal metamorphosis.A total of 101 miRNAs were identified,and 75 miRNAs were differentially expressed during the metamorphic process.The relationship between these differentially expressed miRNAs and 12 ecdysone cascade genes was analyzed by four classical software programs,and a multiple-to-multiple regulatory network was found to exist between these miRNAs and their targets.Among them,miR-14-3p and its two targets(EcR and E75)were chosen for further validation.MiR-14-3p had higher expression level in the 6 th instar larvae as compared with either the prepupae or pupae,which was opposite to that of both EcR and E75,two ecdysone cascade genes.Luciferase reporter assay confirmed that both EcR and E75 were regulated by miR-14-3p.Interestingly,the 3'untranslated regions are nearly identical to each other among different transcript variants of the ecdysone cascade genes,including EcR,USP,E75,E74,E78,E93,Hr3,Hr4,Hr39,K rhl and F tzfl.Thus,different transcript variants of one ecdysone cascade gene could be regulated by the same mi RNA.The above data suggest that the ecdysone signaling pathway is under the tight control of miRNA.These findings expand our understanding of the mechanism of insect metamorphosis and may also provide a novel possibility for the control of pest insects in the future.
文摘The insect midgut epithelium is composed of columnar, goblet, and regenerative cells. Columnar epithelial cells are the most abundant and have membrane protrusions that form the brush border membrane (BBM) on their apical side. These increase surface area available for the transport of nutrients, but also provide opportunities for interaction with xenobiotics such as pathogens, toxins and host plant allelochemicals. Recent improvements in proteomic and bioinfbrmatics tools provided an opportunity to determine the proteome of the T. ni BBM in unprecedented detail. This study reports the identification of proteins from BBM vesicles (BBMVs) using single dimension polyacrylamide gel elec? trophoresis coupled with multi-dimensional protein identification technology. More than 3000 proteins were associated with the BBMV of which 697 were predicted to possess either a signal peptide, at least one transmembrane domain or a GPI-anchor signal. Of these, bioinfbrmatics analysis and manual curation predicted that 185 may be associated with the BBMV or epithelial cell plasma membrane. These are discussed with respect to their predicted functions, namely digestion, nutrient uptake, cell signaling, development, cell-cell interactions, and other functions. We believe this to be the most detailed proteomic analysis of the lepidopteran midgut epithelium membrane to date, which will provide information to better understand the biochemical, physiological and pathological processes taking place in the larval midgut.
基金the National Natural Science Foundation of China(31872426)Guangdong Natural Science Foundation(2018A030310210)+2 种基金Guang-dong Provincial Promotion Project on Preservation and Utilization of Local Breed of Livestock and Poultry(No.2018-143)China Postdoctoral Science Foundation(2017M622714)South China Agricultural University Youth Science and Technology Talents Cultivation Special Fund.
文摘Bombyx mori nucleopolyhedrovirus(BmNPV)is a DNA virus that causes huge losses to the silkworm industry but the piRNA responses during BmNPV infection in the silkworm remain uninvestigated.Here,silkworm piRNA profiles of uninfected and BmNPV-infected fat body and midgut were determined by high-through sequencing in the early stages of BmNPV infection.A total of 2675 and 3396 genome-derived piRNAs were identified from fat body and midgut,respectively.These genome-derived piRNAs mainly originated from unannotated instead of transposon regions in the silkworm genome.In total,572 piRNAs were associated with 280 putative target genes in fat body and 805 piRNAs with 380 target genes in midgut.Compared to uninfected tissues,322 and 129 piRNAs were significantly upregulated in BmNPV-infected fat body and midgut,respectively.In addition,276 and 117 piRNAs were significantly downregulated.Moreover,differentially expressed(DE)piRNAs during BmNPV infection differed significantly between fat body and midgut.Putative DE piRNA-targeted genes were associated with“response to stimulus”and“environmental information processing”in fat body after infection with BmNPV,which may indicate an active piRNA response to BmNPV infection in fat body.This study may lay the foundation for future research of the potential roles of the piRNA pathway and specific piRNAs in BmNPV pathogenesis.
基金This study was supported by the Chinese National Natural Science Foundation(Grant No.31672362)the Scientific Research Cultivation Fund for Young Faculty of South China Normal University(Grant No.2014bsxm 10).
文摘Spodoptera litura is a destructive agricultural pest in tropical and subtropical areas.Understanding the molecular mechanisms of S.litura adaptation to its preferred host plants may help identify target genes useful for pest control.We used high-throughput sequencing to characterize the expression patterns of messenger RNAs(mRNAs)and microRNAs(miRNAs)in the midgut of S.litura fed on Brassica juncea for 6 h and 48 h.A total of 108 known and 134 novel miRNAs were identified,29 miRNAs and 237 mRNAs were differentially expressed at 6 h of B.juncea feeding,26 miRNAs and 433 mRNAs were differentially expressed at 48 h.For the mRNAs,the up-regulated genes were mostly enriched in detoxification enzymes(cytochrome P450,esterase,glutathione^-transferase,uridine diphosphate-glucuronosyl transferase),while the down-regulated genes were mostly enriched in proteinases and immune-related genes.Furthermore,most detoxification enzymes begin to up-regulate at 6 h,while most digestion and immunerelated genes begin to up-or down-regulate at 48 h.Eighteen and 37 differently expressed transcription factors were identified at 6 h and 48 h,which may regulate the functional genes.We acquired 136 and 41 miRNA versus mRNA pairs at 6 h and 48 h,respectively.Some down-regulated and up-regulated miRNAs were predicted to target detoxification enzymes and proteinases,respectively.Real-time quantitative polymerase chain reaction of nine randomly selected miRNAs and 28 genes confirmed the results of RNA-seq.This analyses of miRNA and mRNA transcriptomes provides useful information about the molecular mechanisms of S.litura response to B.juncea.
