Extra-adrenal chromaffin cell-related tumours or paragangliomas are rare, especially in the bladder. In this article, we reported three different clinical cases of bladder paraganglioma, followed by a review of curren...Extra-adrenal chromaffin cell-related tumours or paragangliomas are rare, especially in the bladder. In this article, we reported three different clinical cases of bladder paraganglioma, followed by a review of current literature on the pathophysiology and management of bladder paraganglioma. Case 1 involved a 23 years old female patient who complained of a 10-year history of micturition-related headaches, palpitations and diaphoresis; while in case 2, a 58 years old female patient presented with history of painless haematuria and an incidentally diagnosis of a functioning paraganglioma during endoscopic transurethral resection of bladder tumour; and lastly in case 3, a 54 years old male renal transplant recipient was referred to the urology outpatient with a suspicious bladder mass found incidentally on routine transplant workshop.展开更多
In this paper, we study the classical Allen-Cahn equations and investigate the maximum- principle-preserving (MPP) techniques. The Allen-Cahn equation has been widely used in mathematical models for problems in materi...In this paper, we study the classical Allen-Cahn equations and investigate the maximum- principle-preserving (MPP) techniques. The Allen-Cahn equation has been widely used in mathematical models for problems in materials science and fluid dynamics. It enjoys the energy stability and the maximum-principle. Moreover, it is well known that the Allen- Cahn equation may yield thin interface layer, and nonuniform meshes might be useful in the numerical solutions. Therefore, we apply the local discontinuous Galerkin (LDG) method due to its flexibility on h-p adaptivity and complex geometry. However, the MPP LDG methods require slope limiters, then the energy stability may not be easy to obtain. In this paper, we only discuss the MPP technique and use numerical experiments to dem-onstrate the energy decay property. Moreover, due to the stiff source given in the equation, we use the conservative modified exponential Runge-Kutta methods and thus can use rela-tively large time step sizes. Thanks to the conservative time integration, the bounds of the unknown function will not decay. Numerical experiments will be given to demonstrate the good performance of the MPP LDG scheme.展开更多
Objective:The following article explores our evolving understandings of the role of regenerative technology as an effective penile rehabilitation tool in men with erectile dysfunction(ED)in the setting of prostate can...Objective:The following article explores our evolving understandings of the role of regenerative technology as an effective penile rehabilitation tool in men with erectile dysfunction(ED)in the setting of prostate cancer(PCa)treatment and PCa survivorship.Methods:This narrative clinical review paper summarizes what is currently known about various modalities of regenerative therapy in restoring spontaneous erectile function(EF)in men following PCa treatment with an emphasis on penile rehabilitation strategies.Results:Conventional medical therapy often does not reverse underlying endothelial dysfunction or promote neuro-vasculogenesis to preserve penile health in men with ED.Over the past decade,there has been considerable interest in the role of regenerative therapy to restore endothelial dysfunction and ED without future dependency on medical therapy.Regenerative therapy can be classified into cellular-based(immunomodulators,stem cells,and platelet-rich plasma),biomaterials(nerve graft transfer),and device-related technology(low-intensity shockwave).Although published literature shows early promise in the role of regenerative technology for ED,there is a paucity of high-quality clinical trials in the setting of penile rehabilitation and PCa survivorship to support their use as standard care and be adopted in clinical guidelines.展开更多
In this paper,we propose and analyze a uniformly robust staggered DG method for the unsteady Darcy-Forchheimer-Brinkman problem.Our formulation is based on velocity gradient-velocity-pressure and the resulting scheme ...In this paper,we propose and analyze a uniformly robust staggered DG method for the unsteady Darcy-Forchheimer-Brinkman problem.Our formulation is based on velocity gradient-velocity-pressure and the resulting scheme can be flexibly applied to fairly general polygonal meshes.We relax the tangential continuity for velocity,which is the key ingredi-ent in achieving the uniform robustness.We present well-posedness and error analysis for both the semi-discrete scheme and the fully discrete scheme,and the theories indicate that the error estimates for velocity are independent of pressure.Several numerical experiments are presented to confirm the theoretical findings.展开更多
The real benefits of vitamins and dietary supplementation on health outcomes have always been mired in controversy,and to date,contradictory studies continue to be published to highlight their benefits when downplayin...The real benefits of vitamins and dietary supplementation on health outcomes have always been mired in controversy,and to date,contradictory studies continue to be published to highlight their benefits when downplaying possible adverse effects.!This recently published National Health and Nutrition Examination Survey(NHANES)database study population investigating the role of niacin on erectile function reported that higher niacin intake,specifically in the highest tertile,was associated with a decreased risk of erectile dysfunction(ED)compared to the lowest tertile,showing an odds ratio(OR)of 0.56(95%confidence interval[CI]:0.37-0.85)based on 863 participants with ED from a pool of 3184 adults.2 Further analysis of dose-response curves and interaction analyses found a negative correlation between dietary niacin intake and the risk of ED,suggesting that a higher dietary niacin intake is associated with areducedriskof ED.展开更多
Objective:The aim of the study is to investigate improvements in lower urinary tract symptoms in men with benign prostatic hyperplasia(BPH)treated with prostatic Aquablation.Materials and methods:We performed a litera...Objective:The aim of the study is to investigate improvements in lower urinary tract symptoms in men with benign prostatic hyperplasia(BPH)treated with prostatic Aquablation.Materials and methods:We performed a literature search of clinical trials using the MEDLINE,Embase,and Cochrane Library databases and retrieved published works on Aquablation for the treatment of BPH up to August 2021.Unpublished works,case reports,conference proceedings,editorial comments,and letters were excluded.Risk of bias was assessed using the ROBINS-I tool.Raw means and mean differences were meta-analyzed to produce summary estimates for pre-versus post-international Prostate Symptom Scores,maximum flow rate,and male sexual health questionnaire value changes.An inverse-variance weighted random effects model was used.Results:Seven studies were included in this review(n=551 patients)that evaluated various urological parameters.At 3 months,the International Prostate Symptom Scores raw mean difference from baseline was-16.475(95%confidence interval[CI],-15.264 to-17.686;p<0.001),with improvements sustained for 12 months.Similarly,maximum flow rate improved by+1.96(95%CI,10.015 to 11.878;p<0.001)from pre to 3 months postoperatively.In addition,the male sexual health questionnaire change pooled effect size was-0.55(95%CI,-1.621 to 0.531;p=0.321)from preintervention to postintervention at 3 months.Meta-analyses of some outcomes showed large statistical heterogeneity or evidence of publication bias.Conclusions:Aquablation seems to improve lower urinary tract symptoms in men with BPH while providing relatively preserved sexual function.Further research is required to confirm these preliminary results.展开更多
Semen analysis(SA)remains the cornerstone of male infertility evaluation and should ideally be performed by an accredited andrology laboratory or in vitro fertilization(IVF)clinics based on the standards defined by th...Semen analysis(SA)remains the cornerstone of male infertility evaluation and should ideally be performed by an accredited andrology laboratory or in vitro fertilization(IVF)clinics based on the standards defined by the World Health Organization(WHO)for the Examination and Processing of Human Semen and in accordance with the International Organization for Standardization’s Basic Semen Examination on Specification and Test Methods.展开更多
The artificial urinary sphincter(AUS)remains the standard of care in men with severe stress urinary incontinence(SUI)following prostate surgery and radiation.While the current AUS provides an effective,safe,and durabl...The artificial urinary sphincter(AUS)remains the standard of care in men with severe stress urinary incontinence(SUI)following prostate surgery and radiation.While the current AUS provides an effective,safe,and durable treatment option,it is not without its limitations and complications,especially with regard to its utility in some“high-risk”populations.This article provides a critical review of relevant publications pertaining to AUS surgery in specific high-risk groups such as men with spinal cord injury,revision cases,concurrent penile prosthesis implant,and female SUI.The discussion of each category includes a brief review of surgical challenge and a practical action-based set of recommendations.Our increased understandings of the pathophysiology of various SUI cases coupled with effective therapeutic strategies to enhance AUS surgery continue to improve clinical outcomes of many patients with SUI.展开更多
Penile prosthesis implant(PPI)remains an effective and safe treatment option for men with erectile dysfunction(ED).However,PPI surgery can be associated with a higher risk of complications in certain populations.This ...Penile prosthesis implant(PPI)remains an effective and safe treatment option for men with erectile dysfunction(ED).However,PPI surgery can be associated with a higher risk of complications in certain populations.This article provides a critical review of relevant publications pertaining to PPI in men with diabetes,significant corporal fibrosis,spinal cord injury,concurrent continence surgery,and complex salvage cases.The discussion of each category of special populations includes a brief review of the surgical challenges and a practical action-based set of recommendations.While specific patient populations posed considerable challenges in PPI surgery,strict pre-and postoperative management coupled with safe surgical practice is a prerequisite to achieving excellent clinical outcomes and high patient satisfaction rate.展开更多
We consider a strongly heterogeneous medium saturated by an incompressible viscous fluid as it appears in geomechanical modeling.This poroelasticity problem suffers from rapidly oscillating material parameters,which c...We consider a strongly heterogeneous medium saturated by an incompressible viscous fluid as it appears in geomechanical modeling.This poroelasticity problem suffers from rapidly oscillating material parameters,which calls for a thorough numerical treatment.In this paper,we propose a method based on the local orthogonal decomposition technique and motivated by a similar approach used for linear thermoelasticity.Therein,local corrector problems are constructed in line with the static equations,whereas we propose to consider the full system.This allows to benefit from the given saddle point structure and results in two decoupled corrector problems for the displacement and the pressure.We prove the optimal first-order convergence of this method and verify the result by numerical experiments.展开更多
The simulation of Rayleigh waves is important in a variety of geophysical applications.The computational challenge is the fact that very fine mesh is necessary as the waves are concentrated at the free surface and dec...The simulation of Rayleigh waves is important in a variety of geophysical applications.The computational challenge is the fact that very fine mesh is necessary as the waves are concentrated at the free surface and decay exponentially away from the free surface.To overcome this challenge and to develop a robust high order scheme for the simulation of Rayleigh waves,we develop a mortar discontinuous Galerkin method with staggered hybridization.The use of the mortar technique allows one to use fine mesh in only a local region near the free surface,and use coarse mesh in most of the domain.This approach reduces the computational cost significantly.The staggered hybridization allows the preservation of the strong symmetry of the stress tensor without complicated construction of basis functions.In particular,the basis functions are piecewise polynomial without any continuity requirement,and the coupling of the basis functions is performed by using carefully chosen hybridized variables.The resulting scheme is explicit in time,and only local saddle point system are solved for each time step.We will present several benchmark problems to demonstrate the performance of the proposed method.展开更多
文摘Extra-adrenal chromaffin cell-related tumours or paragangliomas are rare, especially in the bladder. In this article, we reported three different clinical cases of bladder paraganglioma, followed by a review of current literature on the pathophysiology and management of bladder paraganglioma. Case 1 involved a 23 years old female patient who complained of a 10-year history of micturition-related headaches, palpitations and diaphoresis; while in case 2, a 58 years old female patient presented with history of painless haematuria and an incidentally diagnosis of a functioning paraganglioma during endoscopic transurethral resection of bladder tumour; and lastly in case 3, a 54 years old male renal transplant recipient was referred to the urology outpatient with a suspicious bladder mass found incidentally on routine transplant workshop.
基金Jie Du is supported by the National Natural Science Foundation of China under Grant Number NSFC 11801302Tsinghua University Initiative Scientific Research Program+1 种基金Eric Chung is supported by Hong Kong RGC General Research Fund(Projects 14304217 and 14302018)The third author is supported by the NSF grant DMS-1818467.
文摘In this paper, we study the classical Allen-Cahn equations and investigate the maximum- principle-preserving (MPP) techniques. The Allen-Cahn equation has been widely used in mathematical models for problems in materials science and fluid dynamics. It enjoys the energy stability and the maximum-principle. Moreover, it is well known that the Allen- Cahn equation may yield thin interface layer, and nonuniform meshes might be useful in the numerical solutions. Therefore, we apply the local discontinuous Galerkin (LDG) method due to its flexibility on h-p adaptivity and complex geometry. However, the MPP LDG methods require slope limiters, then the energy stability may not be easy to obtain. In this paper, we only discuss the MPP technique and use numerical experiments to dem-onstrate the energy decay property. Moreover, due to the stiff source given in the equation, we use the conservative modified exponential Runge-Kutta methods and thus can use rela-tively large time step sizes. Thanks to the conservative time integration, the bounds of the unknown function will not decay. Numerical experiments will be given to demonstrate the good performance of the MPP LDG scheme.
文摘Objective:The following article explores our evolving understandings of the role of regenerative technology as an effective penile rehabilitation tool in men with erectile dysfunction(ED)in the setting of prostate cancer(PCa)treatment and PCa survivorship.Methods:This narrative clinical review paper summarizes what is currently known about various modalities of regenerative therapy in restoring spontaneous erectile function(EF)in men following PCa treatment with an emphasis on penile rehabilitation strategies.Results:Conventional medical therapy often does not reverse underlying endothelial dysfunction or promote neuro-vasculogenesis to preserve penile health in men with ED.Over the past decade,there has been considerable interest in the role of regenerative therapy to restore endothelial dysfunction and ED without future dependency on medical therapy.Regenerative therapy can be classified into cellular-based(immunomodulators,stem cells,and platelet-rich plasma),biomaterials(nerve graft transfer),and device-related technology(low-intensity shockwave).Although published literature shows early promise in the role of regenerative technology for ED,there is a paucity of high-quality clinical trials in the setting of penile rehabilitation and PCa survivorship to support their use as standard care and be adopted in clinical guidelines.
基金the Hong Kong RGC General Research Fund(Project numbers 14304719 and 14302018)CUHK Faculty of Science Direct Grant 2019-20。
文摘In this paper,we propose and analyze a uniformly robust staggered DG method for the unsteady Darcy-Forchheimer-Brinkman problem.Our formulation is based on velocity gradient-velocity-pressure and the resulting scheme can be flexibly applied to fairly general polygonal meshes.We relax the tangential continuity for velocity,which is the key ingredi-ent in achieving the uniform robustness.We present well-posedness and error analysis for both the semi-discrete scheme and the fully discrete scheme,and the theories indicate that the error estimates for velocity are independent of pressure.Several numerical experiments are presented to confirm the theoretical findings.
文摘The real benefits of vitamins and dietary supplementation on health outcomes have always been mired in controversy,and to date,contradictory studies continue to be published to highlight their benefits when downplaying possible adverse effects.!This recently published National Health and Nutrition Examination Survey(NHANES)database study population investigating the role of niacin on erectile function reported that higher niacin intake,specifically in the highest tertile,was associated with a decreased risk of erectile dysfunction(ED)compared to the lowest tertile,showing an odds ratio(OR)of 0.56(95%confidence interval[CI]:0.37-0.85)based on 863 participants with ED from a pool of 3184 adults.2 Further analysis of dose-response curves and interaction analyses found a negative correlation between dietary niacin intake and the risk of ED,suggesting that a higher dietary niacin intake is associated with areducedriskof ED.
基金sponsored by the Australian-America Fulbright Commission administered through a 2021-2022 Fulbright Future Scholarship funded by the Kinghorn Foundation.
文摘Objective:The aim of the study is to investigate improvements in lower urinary tract symptoms in men with benign prostatic hyperplasia(BPH)treated with prostatic Aquablation.Materials and methods:We performed a literature search of clinical trials using the MEDLINE,Embase,and Cochrane Library databases and retrieved published works on Aquablation for the treatment of BPH up to August 2021.Unpublished works,case reports,conference proceedings,editorial comments,and letters were excluded.Risk of bias was assessed using the ROBINS-I tool.Raw means and mean differences were meta-analyzed to produce summary estimates for pre-versus post-international Prostate Symptom Scores,maximum flow rate,and male sexual health questionnaire value changes.An inverse-variance weighted random effects model was used.Results:Seven studies were included in this review(n=551 patients)that evaluated various urological parameters.At 3 months,the International Prostate Symptom Scores raw mean difference from baseline was-16.475(95%confidence interval[CI],-15.264 to-17.686;p<0.001),with improvements sustained for 12 months.Similarly,maximum flow rate improved by+1.96(95%CI,10.015 to 11.878;p<0.001)from pre to 3 months postoperatively.In addition,the male sexual health questionnaire change pooled effect size was-0.55(95%CI,-1.621 to 0.531;p=0.321)from preintervention to postintervention at 3 months.Meta-analyses of some outcomes showed large statistical heterogeneity or evidence of publication bias.Conclusions:Aquablation seems to improve lower urinary tract symptoms in men with BPH while providing relatively preserved sexual function.Further research is required to confirm these preliminary results.
文摘Semen analysis(SA)remains the cornerstone of male infertility evaluation and should ideally be performed by an accredited andrology laboratory or in vitro fertilization(IVF)clinics based on the standards defined by the World Health Organization(WHO)for the Examination and Processing of Human Semen and in accordance with the International Organization for Standardization’s Basic Semen Examination on Specification and Test Methods.
文摘The artificial urinary sphincter(AUS)remains the standard of care in men with severe stress urinary incontinence(SUI)following prostate surgery and radiation.While the current AUS provides an effective,safe,and durable treatment option,it is not without its limitations and complications,especially with regard to its utility in some“high-risk”populations.This article provides a critical review of relevant publications pertaining to AUS surgery in specific high-risk groups such as men with spinal cord injury,revision cases,concurrent penile prosthesis implant,and female SUI.The discussion of each category includes a brief review of surgical challenge and a practical action-based set of recommendations.Our increased understandings of the pathophysiology of various SUI cases coupled with effective therapeutic strategies to enhance AUS surgery continue to improve clinical outcomes of many patients with SUI.
文摘Penile prosthesis implant(PPI)remains an effective and safe treatment option for men with erectile dysfunction(ED).However,PPI surgery can be associated with a higher risk of complications in certain populations.This article provides a critical review of relevant publications pertaining to PPI in men with diabetes,significant corporal fibrosis,spinal cord injury,concurrent continence surgery,and complex salvage cases.The discussion of each category of special populations includes a brief review of the surgical challenges and a practical action-based set of recommendations.While specific patient populations posed considerable challenges in PPI surgery,strict pre-and postoperative management coupled with safe surgical practice is a prerequisite to achieving excellent clinical outcomes and high patient satisfaction rate.
文摘We consider a strongly heterogeneous medium saturated by an incompressible viscous fluid as it appears in geomechanical modeling.This poroelasticity problem suffers from rapidly oscillating material parameters,which calls for a thorough numerical treatment.In this paper,we propose a method based on the local orthogonal decomposition technique and motivated by a similar approach used for linear thermoelasticity.Therein,local corrector problems are constructed in line with the static equations,whereas we propose to consider the full system.This allows to benefit from the given saddle point structure and results in two decoupled corrector problems for the displacement and the pressure.We prove the optimal first-order convergence of this method and verify the result by numerical experiments.
基金supported by the National Natural Science Foundation of China under grant number NSFC 11801302supported by the Hong Kong RGC General Research Fund(Project numbers 14304719,14302018)and the CUHK Faculty of Science Direct Grant 2018-19。
文摘The simulation of Rayleigh waves is important in a variety of geophysical applications.The computational challenge is the fact that very fine mesh is necessary as the waves are concentrated at the free surface and decay exponentially away from the free surface.To overcome this challenge and to develop a robust high order scheme for the simulation of Rayleigh waves,we develop a mortar discontinuous Galerkin method with staggered hybridization.The use of the mortar technique allows one to use fine mesh in only a local region near the free surface,and use coarse mesh in most of the domain.This approach reduces the computational cost significantly.The staggered hybridization allows the preservation of the strong symmetry of the stress tensor without complicated construction of basis functions.In particular,the basis functions are piecewise polynomial without any continuity requirement,and the coupling of the basis functions is performed by using carefully chosen hybridized variables.The resulting scheme is explicit in time,and only local saddle point system are solved for each time step.We will present several benchmark problems to demonstrate the performance of the proposed method.
