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111.
COVID-19 pandemic leads to health challenges globally, and its diverse aspects need to be uncovered. Multi-organ injuries have been reported by describing potential SARS-CoV-2 entrance routes: ACE2 and TMPRSS2. Since these cell surface receptors’ expression has been disclosed within the male reproductive system, its susceptibility to being infected by SARS-CoV-2 has been summarised through this literature review. Expression of ACE2 and TMPRSS2 at RNA or protein level has been reported across various investigations indicates that the male genitalia potentially is vulnerable to SARS-CoV-2 infection. Presence of SARS-CoV-2 within semen samples and following direct viral damage, secondary inflammatory response causing orchitis or testicular discomfort and finally the amount of viral load leading testicular damage and immune response activation are among probable underlying mechanisms. Therefore, genital examination and laboratory tests should be considered to address the male reproductive tract complications and fertility issues.  相似文献   
112.
MUSASHI (MSI) family plays the main role in the spermatogenesis process. The purpose of this study was the assessment of sperm MSI1 and MSI2, and sperm functional tests in infertile men (n = 30) with varicocele and fertile men (n = 30). Furthermore, MSI1 and MSI2 proteins were assessed in testicular tissue of azoospermic men (n = 9) as well as epididymal spermatozoa and testis of mice. Expression of MSI1 and MSI2 was assessed at RNA and protein levels in human spermatozoa. Sperm concentration and motility were significantly lower, while abnormal sperm morphology, lipid peroxidation, DNA fragmentation and protamine deficiency were significantly higher in men with varicocele compared to fertile individuals. Any significant difference was not observed in the expression of MSI1 and MSI2 mRNA between the two groups. Unlike MSI1 protein that was not detectable in humans, the relative expression of MSI2 protein was similar in varicocele and fertile individuals. The expression level of both Msi1 and Msi2 proteins was also observable in mouse spermatozoa. No significant relationship was observed between sperm functional parameters with expression of these genes. The data of this study demonstrated that although MSI1 and MSI2 play important roles during spermatogenesis, their relative expression in spermatozoa was not affected by varicocele.  相似文献   
113.
BackgroundAlthough pelvic osteotomy (PO) is an important surgical procedure that can alleviate symptoms and potentially slow progression of osteoarthritis in patients with development dysplasia of the hip, some patients eventually require conversion to total hip arthroplasty (THA). This study aimed to determine the outcome of conversion THA in patients with prior PO.MethodsForty nine patients with a history of prior PO who underwent conversion THA at a single institution were matched at a 1:3 ratio based on the date of surgery, age, gender, and body mass index with 147 developmental dysplasia of the hip patients who underwent primary THA without prior PO. A retrospective chart review was performed to compare outcomes at a minimum follow-up of 2 years.ResultsPatients with prior PO required more supplemental screw fixation for the acetabular component (59.2% vs 38.1%, P = .016), more autologous bone grafting (24.5% vs 11.6%, P = .048), had a longer mean operative time (106.0 vs 79.8 minutes, P < .001), and greater estimated blood loss (350.0 vs 206.8 mL, P = .015). Patients with prior PO had smaller cup version angle (26.0° vs 29.0°, P = .012) and greater discrepancy in the limb length (10.3 vs 7.26 mm, P = .041). Eight hips (16.3%) with prior PO and 6 (4.1%) without osteotomy required reoperation (P = .008). There was no difference in outcome scores at the latest follow-up.Conclusion: THA after prior PO is technically demanding, leading to longer operative times, greater blood loss, and variation in implant placement. Although functional outcomes are similar, THA after a prior PO is more likely to require reoperation.ConclusionTHA after prior PO is technically demanding, leading to longer operative times, greater blood loss, and variation in implant placement. Although functional outcomes are similar, THA after a prior PO is more likely to require reoperation.  相似文献   
114.
Hand surgery is a unique field that incorporates multiple specialties, aiming to provide the patient with a best possible functional and aesthetic results. Hand surgeons deal with different pathologies that require skills in several aspects of surgery. The field of hand surgery has evolved significantly over the past decades across the globe. This specialty has also been evolving in Saudi Arabia over the past 25 years. Some of the services offered to patients include specialized centers for brachial plexus, peripheral nerve, and pediatric hand surgery as well as centers for work-related hand injuries. There has also been significant contribution to the hand surgery literature from the hand surgeons working in Saudi Arabia, with hundreds of papers published in journals pertaining to hand surgery, orthopedic surgery, and plastic surgery, as well as the publication of several novel mutations causing congenital hand defects in journals concerned with genetics. The recent approval of a hand and microsurgery fellowship program in Saudi Arabia will also help boost this field in the country and the region.  相似文献   
115.
116.
BackgroundMegaprostheses are commonly used for reconstruction after distal femoral resection in orthopaedic oncology. The polyethylene bearings in these reconstructions experience wear and wear-related complications that may result in revision surgery. Improved manufacturing and processing of polyethylene has increased the durability of components commonly used for routine arthroplasty. Alterations in the manufacture of polyethylene is expected to reduce the revision risk of oncologic megaprostheses, resulting in fewer revision procedures, but this has not been proven.Questions/purposesIs there a difference in the hazard of polyethylene wear or breakage leading to prosthetic revision between differences in polyethylene manufacture and processing based on a competing risk analysis?MethodsThis was a single-center, observational, retrospective comparative study of 224 patients who had distal femur megaprostheses with identical rotating hinge articulations and knee kinematics after oncologic surgery from 1993 to 2015. No differences in surgical indications, joint articular components and kinematics, age, sex, diagnosis, BMI, use of chemotherapy, or tumor stage were seen with the patient numbers available. Prosthetic survivorship free from prosthetic revision surgery because of polyethylene wear-related revisions, defined as breakage, increased excursion on varus-valgus stress, or new locking or giving way was compared between two groups of patients: group 1 polyethylene (P1) (66 patients) who had air-sterilized machined ram-extruded bar stock or group 2 polyethylene (P2) (158 patients) molded gamma-radiated argon-processed polyethylene components. The mean follow-up duration for the P1 group (89 ± 55 months) was not different from that of patients with P2 polyethylene (79 ± 63 months; p = 0.24) including 27% (18 of 66) of patients in the P1 group and 25% (40 of 158) of patients in the P2 group followed for more than 10 years. More patients in the P2 group were lost to follow-up (9.2%, 16 of 174) than in the P1 group (5.7%, 4 of 70) but this was not statistically different (chi square; p = 0.37). The hazard of revision because of polyethylene wear or breakage was calculated with a competing risk analysis using the Fine‐Gray subdistribution hazard model.ResultsThe P1 implants had a higher hazard ratio for revision caused by polyethylene damage at 120 months than did the P2 polyethylene implants (P1 HR 0.24 [95% CI 0.13 to 0.36] versus HR 0.07 [95% CI 0.03 to 0.12]), which represents an estimated absolute risk reduction of 17% (95% CI 6.15 to 27.9).ConclusionPolyethylene damage can result in megaprosthetic revisions in patients undergoing oncologic procedures. The hazard of polyethylene failure resulting in revision surgery was lower in patients who received recent polyethylene than in patients with polyethylene produced by previous methods, enhancing the durability of distal femoral megaprosthetic reconstructions. Despite improvements in polyethylene manufacture and clinical results, revision solely because of polyethylene damage still occurs in 7% of patients by the 10-year timepoint; thus, more improvement is needed. Patients who receive these implants should be monitored for signs and symptoms of polyethylene damage.Level of EvidenceLevel III, therapeutic study.  相似文献   
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118.
BackgroundIt remains challenging to manage antibody-mediated rejection (ABMR) associated with angiotensin II type 1 receptor antibodies (AT1R-Abs) in kidney transplant recipients and the outcomes are not well defined. We describe the presentation, clinical course, and outcomes of this condition.MethodsThis retrospective study included kidney transplant recipients with AT1R-Ab levels ≥10 units/mL and biopsy-proven ABMR in the absence of significant HLA-donor-specific antibodies at the time of rejection.ResultsWe identified 13 recipients. Median creatinine (Cr) at rejection was significantly higher (2.05 mg/dL) compared with baseline (1.2 mg/dL), P = .006. After ABMR management, the difference in median Cr was not significant (1.5 mg/dL), P = .152. Median AT1R-Ab level was higher in the pretransplant sample (34.5 units/mL) compared with the level at rejection (19 units/mL) and after rejection treatment (13 units/mL); however, these differences were not significant, P = .129. Eight of the 13 recipients received antibody reduction therapy with plasmapheresis and intravenous immunoglobulin, and 5 of the 13 recipients had other therapies. After rejection management, 6 of the 13 recipients had improvement in Cr to baseline and 7 of the 13 recipients had > 50% reduction in proteinuria.ConclusionsAT1R-Ab–associated ABMR management and outcomes depend on the clinical presentation and may include antibody-reducing therapies among other therapies. Further prospective cohorts will improve recognizing and managing this condition.  相似文献   
119.
Epidermolysis bullosa (EB) is a rare genetic disorder characterized by the formation of blisters and wounds in skin and mucous membranes; it is classified into four types and has various methods of treatment. Management of previous wounds and prevention of formation of new lesions are the most important strategies in the course of therapy to improve patient's quality of life; lack of wound management can lead to further complications such as infection. The current study investigated the therapeutic effects of allogeneic platelet gel (prepared from umbilical cord blood) in a group of children diagnosed with dystrophic epidermolysis bullosa (DEB) eligible for surgical correction of pseudosyndactyly in the hand. The post‐surgical clinical outcome in this group was compared with the clinical outcomes of DEB patients receiving the standard treatment (paraffin gauze wound dressing and topical antibiotics) after corrective surgery. The current study results showed an increase in the rate of recovery and promotion of tissue granulation, complete wound healing, and a decrease in pain level and treatment period. The application of cord blood platelet gel topical dressing was not a conventional method of treatment in patients with DEB wounds and blisters. However, the current study results demonstrated that this gel dressing could effectively accelerate epithelialization and healing of the wounds and decrease patients' pain and post‐surgical recovery period, which altogether leads to improvements in patients' overall quality of life.  相似文献   
120.
IntroductionWhile numerous current clinical trials are testing novel salvage therapies (ST) for patients with recurrent nonmuscle invasive bladder cancer (NMIBC) after bacillus Calmette-Guérin (BCG), the natural history of this disease state has been poorly defined to date. Herein, we evaluated oncologic outcomes in patients previously treated with BCG and ST who subsequently underwent radical cystectomy (RC).MethodsWe identified 378 patients with high-grade NMIBC who received at least one complete induction course of BCG (n = 378) with (n = 62) or without (n = 316) additional ST and who then underwent RC between 2000 and 2018. Oncologic outcomes were compared using the Kaplan-Meier method and Cox proportional hazards models. Sensitivity analyses were conducted stratifying by presenting tumor stage, matched 1:3 for receipt vs. no receipt of ST.ResultsPatients receiving ST were more likely to initially present with CIS (26% vs. 17%) and less likely with T1 disease (34% vs. 50%, P = 0.06) compared to patients not treated with ST. Receipt of ST was not associated with increased risk of adverse pathology (≥pT2 or pN+) at RC (31% vs. 41%, P = 0.14). Likewise, 5-year cancer-specific survival did not significantly differ between groups on univariable Kaplan-Meier analysis (73% for ST and 74% for no ST, P = 0.7). Moreover, on multivariable analysis, receipt of ST was not significantly associated the risk of death from bladder cancer (HR 1.12; 95% CI 0.60–2.09, P = 0.7). Results were unchanged on sensitivity analysis.ConclusionsThese data suggest that, in carefully selected patients, ST following BCG for high grade NMIBC does not compromise oncologic outcomes for patients who ultimately undergo RC.  相似文献   
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