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81.
BackgroundRacial and ethnic disparities in access to hip and knee total joint arthroplasty (TJA) and postoperative outcomes have wide-reaching implications for patients and the health care system. The aim of this study is to evaluate the effect of ethnicity on clinical outcomes and complications following revision hip and knee TJA.MethodsA single-institution, retrospective analysis of a consecutive series of 4424 revision hip and knee TJA patients was evaluated. Student’s t-test and chi-squared analysis were used to identify significant differences in patient demographics and clinical outcomes between Caucasians and various ethnic minorities, including African Americans, Hispanics, and Asians.ResultsWhen compared with white patients, African American patients demonstrated a significantly higher BMI (P = .04), ASA score (P = .04), length of hospital stay (P = .06), and postoperative infection rates (P = .04). Hispanics demonstrated a significantly higher BMI (P = .04), when compared with white patients, alongside a significantly higher risk for postoperative infection (P < .01). African American demonstrated a significantly higher ASA score (P = .02; P = .03), when compared with Hispanics and Asians, alongside a significantly increased length of stay (P = .01) and higher risk for postoperative infection (P = .02).ConclusionThe study findings demonstrate an underutilization of revision TJA by ethnic minority groups, suggesting that disparities in access to orthopedic surgery increase from primary to revision surgery despite higher failure rates of minority ethnic groups reported after primary TJA surgery. In addition, inferior postoperative outcomes were associated with African Americans and Hispanics, when compared to white patients, with African Americans demonstrating the highest risk of postoperative complications.  相似文献   
82.
IntroductionLiving-donor liver transplantation (LDLT) has been mostly suspended and deceased-donor living transplantation activity has been considerably reduced because of coronavirus disease 2019 (COVID-19). We modified our protocols and procedures in line with COVID-19 guidelines. Since the restructuring, we have performed 20 LDLTs. Our study reports the outcomes of these cases and demonstrates the feasibility of LDLT during this pandemic.Materials and MethodsThe changes were influenced by experiences and communications from across the globe. A month-long self-imposed moratorium was spent in restructuring the program and implementing new protocols. Twenty LDLTs were performed between April 18 and September 15 using the new protocols. Our experience includes 2 simultaneous liver-kidney transplants, 1 ABO-incompatible LDLT, and 1 pediatric case (age 11 months).ResultsNineteen patients recovered and 1 patient died. We maintained our postoperative immunosuppression protocol without many changes. Major complications were observed in 30% of recipients but none of the donors. One recipient was infected with COVID-19 during the postoperative period. A donor-recipient couple contracted COVID-19 after discharge from the hospital. All patients recovered from COVID-19 and liver enzymes were unaffected.ConclusionThis study represents a microcosm of experience in LDLT during the COVID-19 era. Outcomes of LDLT are not affected by COVID-19 per se, provided that we make necessary changes.  相似文献   
83.
BackgroundDeveloping a noninvasive clinical test to accurately diagnose kidney allograft rejection is critical to improve allograft outcomes. Urinary exosomes, tiny vesicles released into the urine that carry parent cells’ proteins and nucleic acids, reflect the biologic function of the parent cells within the kidney, including immune cells. Their stability in urine makes them a potentially powerful tool for liquid biopsy and a noninvasive diagnostic biomarker for kidney-transplant rejection.MethodsUsing 192 of 220 urine samples with matched biopsy samples from 175 patients who underwent a clinically indicated kidney-transplant biopsy, we isolated urinary exosomal mRNAs and developed rejection signatures on the basis of differential gene expression. We used crossvalidation to assess the performance of the signatures on multiple data subsets.ResultsAn exosomal mRNA signature discriminated between biopsy samples from patients with all-cause rejection and those with no rejection, yielding an area under the curve (AUC) of 0.93 (95% CI, 0.87 to 0.98), which is significantly better than the current standard of care (increase in eGFR AUC of 0.57; 95% CI, 0.49 to 0.65). The exosome-based signature’s negative predictive value was 93.3% and its positive predictive value was 86.2%. Using the same approach, we identified an additional gene signature that discriminated patients with T cell–mediated rejection from those with antibody-mediated rejection (with an AUC of 0.87; 95% CI, 0.76 to 0.97). This signature’s negative predictive value was 90.6% and its positive predictive value was 77.8%.ConclusionsOur findings show that mRNA signatures derived from urinary exosomes represent a powerful and noninvasive tool to screen for kidney allograft rejection. This finding has the potential to assist clinicians in therapeutic decision making.  相似文献   
84.
Journal of Public Health - Nepal is a country of low endemicity for chronic hepatitis B, with a prevalence of 0.9%. However, in Dolpo District, a higher prevalence of hepatitis B virus (HBV) was...  相似文献   
85.
The impressive rise in the number of elderly persons (65 years and over) will continue in the next two to three decades. Urinary incontinence is a common problem in the elderly, adversely affecting medical, social, and "quality of life" aspects. The cost of urinary incontinence is substantial and is expected to escalate enormously (e.g., by 160% from 1980 to 2040). An aggressive approach toward the diagnosis and management of urinary incontinence can result in an impressive reduction in health care costs and improvement in the quality of life.  相似文献   
86.
Intravitreal drug administration with depot devices   总被引:2,自引:0,他引:2  
The administration of medications by depot devices is a rapidly developing technology in ocular therapeutics. Sustained delivery of ophthalmic medications is a novel approach to treating chronic ocular conditions where systemic therapy may be accompanied by unwanted side effects and where repeated intravitreal drug administration carries significant risks. Eye diseases particularly suitable to this form of treatment include proliferative vitreoretinopathy and chronic intraocular infections such as cytomegalovirus retinitis. Liposomes, which have been extensively investigated over the last two decades, have not found any acceptable clinical application. Nonerodible polymers such as the ethylvinyl acetate/polyvinyl alcohol cup are in advanced phase III trials. The current status of microsphere development in the treatment of posterior segment disease is examined in the review and studies investigating the potential uses of the osmotic minipump are mentioned.  相似文献   
87.
A rare case of splenic abscess occurring after blunt abdominal trauma in a previously healthy boy is reported. The diagnosis was made by ultrasonography. The patient recovered after splenectomy and drainage of subphrenic and intraperitoneal pus.  相似文献   
88.
 Amyloidosis is a complication of long-term hemodialysis treatment. The major histological feature of hemodialysis-associated amyloidosis (HAA) is the deposition of amyloid fibrils in the affected lesions, due, in part, to elevated serum β2-microglobulin (β2M) levels. In vitro studies reveal that serum immunoglobulin light and heavy chains co-deposit with β2M in tissues affected by HAA. Only one study of HAA has been performed in young dialysis patients. We therefore assessed risk factors for HAA in a group (n=30) of young (18.7±0.9 years) patients receiving chronic, uninterrupted hemodialysis using cellulose acetate membranes. All patients initiated dialysis before reaching 18 years of age. The pre-dialysis serum β2M level was 49.7±3.9 mg/l (normal 0–2.4 mg/l). Since serum albumin was normal (4.3±0.1 mg/dl) and serum protein/albumin was elevated (1.7±0.0, normal 1.2–1.5), indicating increased circulating protein, we assayed immunoglobulins in the same patients. The serum immunoglobulin levels (expressed as a percentage of the total level of serum proteins) were elevated (21.3±0.9%, normal 11.1%–21.0%). The Kt/v was 1.37±0.03, suggesting that the high levels of serum β2M and immunoglobulins were not due to inadequate dialysis in these patients. Patients with residual renal function (Kr) did display significantly lower serum levels of β2M (33.2±2.3, P=0.03). Furthermore, improved clearance of β2M correlated with higher values of Kr (r=0.914). In contrast, serum levels of immunoglobulin (22.6±3.7, P=0.5) were unaffected by Kr. In addition, there was no correlation between older age at onset of dialysis and serum levels of either β2M (r=0.107) or immunoglobulins (r=0.321). Finally, the length of time on dialysis had no effect on serum levels of either β2M (r=0.105) or immunoglobulins (r=0.092). Taken together, these results indicate that young hemodialysis patients may be at risk for HAA. Received: 13 January 1998 / Revised: 1 June 1998 / Accepted: 2 June 1998  相似文献   
89.
Recombinant adeno-associated virus (rAAV) is a promising vector for retinal application as it transduces photoreceptors and retinal pigment epithelium cells efficiently and in a stable fashion. Because rAAV also transduces retinal ganglion cells, we reasoned that ocular application of rAAV might result in delivery of transgenic protein to the CNS. Here we describe high levels of green fluorescent protein (GFP) persisting at least 6 months in optic nerves and brains of mice and dogs after intravitreal delivery of rAAV-GFP. There was no clinical or histological evidence of inflammatory response although a mild humoral Th-2 response to viral capsid proteins was detected. These findings have important implications with respect to therapeutic applications of rAAV.  相似文献   
90.
Glutathione-S-transferase activity has been demonstrated in the brain of rabbit, guinea pig, rat, mouse, and pigeon. The activity was in the following order: rabbit > (guinea pig = mouse) > rat > pigeon. The activity of brain was about 1/3 to 1/9 of that present in liver depending upon the species. In the rat brain glutathione-S-transferase activity was found to be distributed equally in cerebrum, cerebellum, and brain stem and localized mainly in the organelle-free cytosol fraction.  相似文献   
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