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101.
Cory J. Weaver Yuk Fai Leung Daniel M. Suter 《The Journal of comparative neurology》2016,524(10):2130-2141
Nicotinamide dinucleotide phosphate oxidases (NOX) control various cellular signaling cascades. In the nervous system, there is recent evidence that NOX‐derived reactive oxygen species (ROS) regulate neurite outgrowth, regeneration, and stem cell proliferation; however, a comprehensive NOX gene expression analysis is missing for all major model systems. Zebrafish embryos provide an excellent model system to study neurodevelopment and regeneration because they develop quickly and are well suited for in vivo imaging and molecular approaches. Although the sequences of five NOX genes (nox1, nox2/cybb, nox4, nox5, and duox) have been identified in the zebrafish genome, nothing is known about their expression pattern. Here, we used quantitative polymerase chain reaction combined with in situ hybridization to develop a catalog of nox1, nox2/cybb, nox5, and duox expression in zebrafish during early nervous system development from 12 to 48 hours post fertilization. We found that expression levels of nox1, nox5, and duox are dynamic during the first 2 days of development, whereas nox2/cybb levels remain remarkably stable. By sectioning in situ hybridized embryos, we found a pattern of broad and overlapping NOX isoform expression at 1 and 1.5 days post fertilization. After 2 days of development, a few brain regions displayed increased NOX expression levels. Collectively, these results represent the first comprehensive analysis of NOX gene expression in the zebrafish and will provide a basis for future studies aimed at determining the functions of NOX enzymes in neurodevelopment and regeneration. J. Comp. Neurol. 524:2130–2141, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
102.
Sonnadara R Rittenhouse N Khan A Mihailidis A Drozdzal G Safir O Leung SO 《American journal of surgery》2012,203(1):32-36
BackgroundEstablished methods for assessing surgical performance face limitations. Global rating scales and procedure-specific checklists are resource intensive and rely on expert opinions. Alternatives that use technology to track hand movements, such as magnetic and optical tracking systems, are generally expensive and ill suited to the surgical environment.MethodsThe authors present a new platform that integrates a novel, low-cost optical tracking system, magnetic tracking technology and a videographic recording system to quantify surgical performance synchronously across all modalities. The validity of this platform was tested by examining its ability to differentiate between the performance of expert and novice participants on a basic surgical task.ResultsEach modality was able to differentiate between expert and novice participants, and metrics were well correlated across modalities.ConclusionsThe authors have developed a platform for assessing surgical performance. It can operate in the absence of expert raters and has the potential to provide immediate feedback to trainees. 相似文献
103.
Data on the association between dietary vitamin K intake and fracture risk are limited among Chinese. This study examined
such an association in community-dwelling elderly in Hong Kong. We present data from 2,944 subjects (1,605 men, 1,339 women)
who participated in a prospective cohort study. Baseline dietary intakes of energy, protein, calcium, vitamin D, and vitamin
K were assessed using a food-frequency questionnaire. Data on incident hip fracture and nonvertebral fracture during a median
of 6.9 follow-up years were collected from a hospital database. Cox regression analyses were performed with adjustments for
age, education attainment, smoking status, alcohol use, body mass index, hip bone mineral density, physical activity, use
of calcium supplement, and energy-adjusted nutrient intakes. There were 29 (1.8 %) men and 19 (1.4 %) women with incident
hip fractures and 97 (6.0 %) men and 88 (6.6 %) women with nonvertebral fractures. The median (interquartile range) of dietary
vitamin K intake was 241.8 (157.5–360.8) and 238.9 (162.4–343.6) μg/day in men and women, respectively. Similar dietary vitamin
K intakes were observed between subjects with hip or nonvertebral fractures and subjects without hip or nonvertebral fractures.
In both men and women, dietary vitamin K intake was not associated with fracture risks at all measured sites in either crude
or adjusted models. In Chinese community-dwelling elderly, hip or nonvertebral fracture risk was not associated with dietary
vitamin K intake. The high dietary vitamin K intake of the studied group may have limited the ability to detect the association
between vitamin K intake and fracture risk. 相似文献
104.
Lin M Yiu WH Wu HJ Chan LY Leung JC Au WS Chan KW Lai KN Tang SC 《Journal of the American Society of Nephrology : JASN》2012,23(1):86-102
Inflammation contributes to the tubulointerstitial lesions of diabetic nephropathy. Toll-like receptors (TLRs) modulate immune responses and inflammatory diseases, but their role in diabetic nephropathy is not well understood. In this study, we found increased expression of TLR4 but not of TLR2 in the renal tubules of human kidneys with diabetic nephropathy compared with expression of TLR4 and TLR2 in normal kidney and in kidney disease from other causes. The intensity of tubular TLR4 expression correlated directly with interstitial macrophage infiltration and hemoglobin A1c level and inversely with estimated glomerular filtration rate. The tubules also upregulated the endogenous TLR4 ligand high-mobility group box 1 in diabetic nephropathy. In vitro, high glucose induced TLR4 expression via protein kinase C activation in a time- and dose-dependent manner, resulting in upregulation of IL-6 and chemokine (C-C motif) ligand 2 (CCL-2) expression via IκB/NF-κB activation in human proximal tubular epithelial cells. Silencing of TLR4 with small interfering RNA attenuated high glucose-induced IκB/NF-κB activation, inhibited the downstream synthesis of IL-6 and CCL-2, and impaired the ability of conditioned media from high glucose-treated proximal tubule cells to induce transmigration of mononuclear cells. We observed similar effects using a TLR4-neutralizing antibody. Finally, streptozotocin-induced diabetic and uninephrectomized TLR4-deficient mice had significantly less albuminuria, renal dysfunction, renal cortical NF-κB activation, tubular CCL-2 expression, and interstitial macrophage infiltration than wild-type animals. Taken together, these data suggest that a TLR4-mediated pathway may promote tubulointerstitial inflammation in diabetic nephropathy. 相似文献
105.
Tracy Y. Zhu James F. Griffith Ling Qin Vivian W. Y. Hung Tsz-Ning Fong Anthony W. Kwok Ping-Chung Leung Edmund K. Li Lai-Shan Tam 《Calcified tissue international》2012,91(5):343-355
We assessed the relationship of bone density and microarchitecture between hand, peripheral, and axial skeletal sites using high-resolution peripheral quantitative computed tomography (HR-pQCT) and dual-energy X-ray absorptiometry (DXA) in patients with rheumatoid arthritis (RA) and which factors influence these parameters. This was a cross-sectional study of 100 female patients (53.4?±?9.3?years) with RA. HR-pQCT scans at distal radius and the second metacarpal head were performed to assess cortical and trabecular volumetric bone mineral density (vBMD) and microarchitecture. DXA scans at the hip, lumbar spine, and ultradistal radius were performed to assess areal BMD. There was significant correlation in vBMD and microarchitectural parameters between the second metacarpal head and distal radius (r?=?0.201?0.628). Areal BMD at the axial skeleton was moderately associated with vBMD at the peripheral sites (r?=?0.354–0.558). Factors related to disease severity/chronicity significantly correlated with vBMD and microarchitecture at the distal radius and the second metacarpal head. Factors related to disease activity were more likely to correlate with vBMD and microarchitecture at the second metacarpal head but not those at the distal radius. HR-pQCT is a promising technique that is capable of providing detailed quantitative assessment of disease-associated periarticular bone loss at both cortical and trabecular bone compartments in patients with RA. Future longitudinal studies will be needed to investigate whether assessment by HR-pQCT can be used as a marker of disease activity and a predictor of disease progression in RA. 相似文献
106.
Tewari A Grover S Sooriakumaran P Srivastava A Rao S Gupta A Gray R Leung R Paduch DA 《BJU international》2012,109(4):596-602
Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Orgasm has a major influence on patients’ satisfaction with the overall sexual experience, and alternations in orgasm are associated with significant reductions in emotional and physical satisfaction, which in turn may lead to sexual avoidance behaviour, disharmonious relationships and relationship breakdowns. Studies have found a reduction in orgasmic function after retropublic radical prostatectomy. While open radical prostatectomy inevitably damages some pelvic neuronal circuitry, which will thus impact on orgasmic responses, there is a paucity of data investigating the effect on robotic assisted radical prostatectomy on this. To our knowledge this study represents the largest analysis of orgasmic function in the robotic prostatectomy literature, and therefore would be of value to surgeons in counseling candidates for RALP about orgasmic outcomes. In our series, young men (age ≤60 years) and those who underwent bilateral nerve sparing approaches had a better recovery of their premorbid orgasmic function when compared to older men or men with no nerve sparing.
OBJECTIVE
- ? To investigate orgasmic outcomes in patients undergoing robotic‐assisted laparoscopic radical prostatectomy (RALP) and the effects of age and nerve sparing on these outcomes.
PATIENTS AND METHODS
- ? Between January 2005 and June 2007, 708 patients underwent RALP at our institution.
- ? We analysed postoperative potency and orgasmic outcomes in the 408 men, of the 708, who were potent, able to achieve orgasm preoperatively and available for follow‐up.
RESULTS
- ? Of men aged ≤60 years, 88.4% (198/224) were able to achieve orgasm postoperatively in comparison to 82.6% (152/184) of older men (P < 0.001).
- ? Of patients who received bilateral nerve sparing (BNS) during surgery, 273/301 (90.7%) were able to achieve orgasm postoperatively compared with 46/56 (82.1%) patients who received unilateral nerve sparing and 31/51 (60.8%) men who received non‐nerve‐sparing surgery (P < 0.001).
- ? In men ≤60 years who also underwent BNS, decreased sensation of orgasm was present in 3.2% of men, and postoperative orgasmic rates were significantly better than men ≤60 years who underwent unilateral or no nerve sparing (92.9% vs 83.3% vs 65.4%, respectively; P < 0.001).
- ? Potency rates were also significantly higher in men ≤60 years and in those who underwent BNS.
CONCLUSIONS
- ? Age and nerve sparing influence recovery of orgasm and erectile function after RALP.
- ? Men ≤60 years old and those who undergo BNS are most likely to maintain normal sexual function.
107.
Li PK Chu KH Chow KM Lau MF Leung CB Kwan BC Tong YF Szeto CC Ng MM 《Nephrology (Carlton, Vic.)》2012,17(5):514-518
Aim: We aimed to gain an understanding of patient concerns while on a transplantation waiting list in areas with long transplant waiting time. Methods: The study population comprised patients with organ failure on the transplant waiting list in Hong Kong. They were invited to complete a questionnaire survey. Demographic data and waiting time were collected. Respondents rated their chance of getting transplanted, their subjective concerns and feelings, level of happiness and support received. Results: A total of 442 patients on the waiting list for kidney, liver, lung and heart‐lung transplants completed the questionnaire survey. The majority of patients (93.0%) were waiting for kidney transplantation. More than half of the respondents (63.3%) had been waiting for more than 3 years. Patients with longer transplant waiting times had lower self‐estimated chance of receiving a transplant (P = 0.004). Self‐estimated chance of getting transplanted was positively associated with the happiness score (P < 0.0001). Issues of most concerns to the patients waiting for organ transplants were: inconvenience of therapy (48.2%), disease progression (47.9%), burden to family (59.5%) and financial difficulties (52.3%). More female patients on the waiting list (50.0% vs 25.7% in male) reported concerns about suffering associated with the illnesses. 21.7% of patients considered the level of support received inadequate. Conclusions: Our patients had long waiting time for transplantation, which is associated with a lower perceived chance of getting a transplant. Attention to more psychosocial support to these patients waiting for organ transplant is important. Promoting and improving organ donation would be the ultimate way to help these patients. 相似文献
108.
Leung Wai Sang S Chaturvedi RK Iqbal S Lachapelle K de Varennes B 《Journal of cardiac surgery》2012,27(4):408-414
Abstract Aim: The aim of this study was to determine the midterm functional quality of life in octogenarians after open valvular surgery. Methods: One hundred and eighty‐five consecutive patients above age 80 had valvular surgery with or without coronary artery bypass grafting (CABG). Using the Karnofsky Performance score and Barthel Index, patients were evaluated for functional autonomy, living disposition, and leisure activity by a single telephone interview. Subgroup analysis was performed on the 49 cases of isolated aortic valve replacement (AVR). Results: Mean age of octogenarians undergoing valvular surgery was 82.7 years (range 80 to 92 years). Actuarial survival at one and three years was 71% and 59%, respectively, for the entire group, compared to 84% and 71%, respectively, for isolated AVRs. After a mean follow‐up of 38 months there were 110 survivors (59.5%). Among survivors, 66% were autonomous, 26% semiautonomous, and 8% deemed dependent. Seventy‐two percent were living at home, 19% in a residence, and 9% in a supervised nursing facility. Over 90% of patients pursued leisure activities in the social, cognitive, and physical domains. Conclusions: Valvular surgery in high‐risk octogenarians, can be performed with acceptable mortality rates, and provide patients with functional autonomy and an excellent quality of life. (J Card Surg 2012;27:408‐414) 相似文献
109.
IntroductionTo review the outcome of patients with post-traumatic acute subdural haematoma (ASDH) before and after the establishment of a hospital trauma team at a designated trauma centre.MethodA retrospective analysis was conducted on 82 consecutive patients who underwent surgery for post-traumatic ASDH. The ‘PRE’ and ‘POST’ groups included patients admitted before and after the establishment of a hospital trauma team, respectively.Injury severity was assessed by the admission Glasgow coma score, imaging findings, and the revised trauma score. Clinical outcome measures were the hospital length of stay and the Glasgow outcome score (GOS) upon hospital discharge.ResultsThe overall mortality rate was 53.7%. No significant difference was found between the PRE and POST groups. The mean length of hospital stay was also comparable between the two groups. The functional status of those who survived acute hospital care was significantly better in the POST group. Good outcome (GOS of 4 or 5) was achieved in 66.7% of the survivors in the POST group, compared with 25.0% in the PRE group (p = 0.024).ConclusionPost-traumatic ASDH carried a poor prognosis. The mortality rate and hospital length of stay of patients were not found to be reduced after the establishment of a hospital trauma team. The latter, however, was associated with significantly better functional outcome amongst survivors. Although causality cannot be established due to the multitude of factors which may have affected patient outcome, our findings nonetheless provide further support for the introduction of a multidisciplinary hospital trauma team for the optimal care of trauma patients. 相似文献
110.
Alice Leung MD Foong‐Yen Lim MD Mounira Habli MD Helen N. Jones PhD James M. Wilson MD PhD Timothy M. Crombleholme MD 《Wound repair and regeneration》2012,20(4):592-600
Cell specific gene transfer and sustained transgene expression are goals of cutaneous gene therapy for tissue repair and regeneration. Adeno‐associated virus serotype 2 (AAV2/2) mediated gene transfer to the skin results in stable transgene expression in the muscle fascicles of the panniculus carnosus in mice, with minimal gene transfer to the dermal or epidermal elements. We hypothesized that pseudotyped AAV vectors may have a unique and characteristic tropism and transduction efficiency profile for specific cells in the cutaneous wounds. We compared transduction efficiencies of cells in the epidermis, cells in the dermis, and the fascicles of the panniculus carnosus by AAV2/2 and three pseudotyped AAV vectors, AAV2/5, AAV2/7, and AAV2/8 in a murine excisional wound model. AAV2/5 and AAV2/8 result in significantly enhanced transduction of cells both in the epidermis and the dermis compared to AAV2/2. AAV2/5 transduces both the basilar and supra‐basilar keratinocytes. In contrast, AAV2/8 transduces mainly supra‐basilar keratinocytes. Both AAV2/7 and AAV2/8 result in more efficient gene transfer to the muscular panniculus carnosus compared to AAV2/2. The capsid of the different pseudotyped AAV vectors produces distinct tropism and efficiency profiles in the murine wound healing model. Both AAV2/5 and AAV2/8 administration result in significantly enhanced gene transfer. To further characterize cell specific transduction and tropism profiles of the AAV pseudotyped vectors, we performed in vitro experiments using human and mouse primary dermal fibroblasts. Our data demonstrate that pseudotyping strategy confers a differential transduction of dermal fibroblasts, with higher transduction of both human and murine cells by AAV2/5 and AAV2/8 at early and later time points. At later time points, AAV2/2 demonstrates increased transduction. Interestingly, AAV2/8 appears to be more efficacious in transducing human cells as compared to AAV2/5. The pseudotype‐specific pattern of transduction and tropism observed both in vivo and in vitro suggests that choice of AAV vectors should be based on the desired target cell and the timing of transgene expression in wound healing for gene transfer therapy in dermal wounds. 相似文献