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111.
We report four sickle cell anemia patients who have received multiple blood transfusions and have been non-compliant on Desferal chelation therapy. Abdominal ultrasonography demonstrated an echogenic pancreas in all four patients. Magnetic resonance imaging in three patients revealed decreased signal intensity in all sequences in the pancreas and liver. All four patients had marked iron deposition on liver biopsy. To our knowledge, increased echogenicity of the pancreas secondary to hemosiderosis (2o hemochromatosis) in sickle cell patients has not been reported in the radiologic literature. 相似文献
112.
Evolution of Endpoints for Renal Transplant Outcome 总被引:3,自引:0,他引:3
Sundaram Hariharan Maureen A. McBride Eric P. Cohen 《American journal of transplantation》2003,3(8):933-941
Progressive improvement in short-term kidney transplant survival and reduction in acute rejection rates have restricted our ability to assess newer therapy. Past and present conventional endpoints, such as short-term graft survival and acute rejection rates, are no longer practical. This has prompted investigators to search for alternative endpoints. Long-term graft survival is an ideal endpoint. However, this requires a large cohort of patients with longer follow-up. A simpler approach would be to identify short-term markers, which can predict long-term survival. Short-term potential markers that can predict long-term survival are: clinical (renal function), histological (renal pathological markers) and immunological (anti-donor antibody, blood and urine cytokines). Post-transplant renal function estimated by serum creatinine, cystatin C and creatinine clearance within 1 year, and histological indices, as the Banff chronicity score, have the potential to predict long-term graft survival. Serum creatinine is limited as a marker by its variability based on recipient age, body weight, race and sex. Histological indices are limited, due to the invasive nature of evaluation. Post-transplant renal function and histological indices can be used potentially as a composite endpoint, in combination with conventional endpoints, such as graft loss, death and acute rejection. A practical approach for assessing newer therapies in future studies is to use composite endpoints, which combine conventional endpoints (graft loss, death, acute rejection) with newer endpoints (renal function, histological indices). 相似文献
113.
Cerebral zygomycosis 总被引:3,自引:0,他引:3
Sundaram C Mahadevan A Laxmi V Yasha TC Santosh V Murthy JM Purohit AK Mohandas S Shankar SK 《Mycoses》2005,48(6):396-407
Fifty-six patients with cerebral zygomycosis (mucormycosis) were seen during the period 1971-2001 in two tertiary care hospitals located in south India with tropical climate and catering to neurological diseases. Forty-four patients had rhinocerebral and twelve patients had isolated central nervous system (CNS) zygomycosis. Of these, ten were culture proven (Rhizopus oryzae in eight and Mucor in two); 30 were diagnosed as probable and 16 were diagnosed possible; mixed infections were seen in three patients. Diabetes mellitus was the predisposing condition in a majority (31/44) of patients with the rhinocerebral form of zygomycosis. The tissue obtained at biopsy/autopsy in either form showed necrotic/infarcted tissue with neutrophilic infiltration with broad non-septate hyphae showing irregular branching. The outcome was poor despite surgical excision and antifungal therapy. The high concentration of spores in a mouldy environment, the bird population and improper disposal of hospital waste may facilitate healthy hosts presenting with primary CNS disease. 相似文献
114.
Yu DH Chatterton JE Bliesath JR Sundaram R Ke N Nguy V Meyhack B Wong-Staal F Li QX 《Assay and drug development technologies》2005,3(4):401-411
Transient transfection of short interfering RNAs to inactivate cancer therapeutic genes in cancer cells is an important method to induce therapeutic phenotypes (cell apoptosis, growth arrest, etc.) for cancer target validation. These phenotypes can be initially assessed by cell survival via colorimetric/fluorescence readings, e.g., alamarBlue (Trek Diagnostic Systems, Cleveland, OH) and WST-1. However, intrinsic problems exist for transient transfection-varying toxicity, inconsistent transfection efficiency, as well as other cell-specific determinants-which contribute to a low signal:noise ratio of the assays, rendering of the assay ineffective particularly when applied in high-throughput screening (HTS) multiplexed for different cells. This report describes a method using reporter as a "normalized surrogate" for the conventional survival readout in a 96-well format. In this approach, only the transfected surviving cells produce reporter activities, and many variables associated with transient transfection are excluded. A constitutively expressed reporter gene (luciferase or LacZ) expression cassette is co-transfected into cells along with a specially designed RNA interference (RNAi) vector (or a transgene for that matter). The reporter activity in either liquid cultures or in soft agar cultures in 96-well formats is then quantitated in situ. The RNAi vector construction is simplified so that it can be adapted to a 96-well format. Our data demonstrated that the relative reporter readings for survival are independent of both transfection efficiency and cellular toxicity. The signal:noise ratio is markedly increased, particularly for cells with low transfection efficiency. The assay is versatile and robust and can be applied in multiplexed HTS for cancer target identification and validation. 相似文献
115.
BaCKGROUND: Due to the aging general population, deceased donors > or =55 years will form an increasingly larger proportion of the deceased kidney donor pool. METHODS: Using data from the United States Renal Data System, we determined the change in graft survival between 1996 and 2000 among 32,557 recipients of donors aged <55 years and > or =55 years in univariate and multivariate survival analyses. We identified donor risk factors for graft loss that might influence the decision to accept or reject donors <55 and > or =55 years. The initial glomerular filtration rate established 6 months after transplantation (initial GFR), and the stability of GFR in the first post-transplant year (GFR at 12 months post-transplantation-GFR at six months post-transplantation) were compared between recipients of donors <55 and > or =55 years and the association of these factors with graft survival was determined. RESULTS: In 2000, one-year graft survival in donors > or =55 years was 86.7%. Between 1996 and 1999 the projected graft half life improved from 11.4 to 14.5 years for recipients of donors <55 years (P < 0.01); however, there was no improvement for recipients of donors > or =55 years (8.2 to 9.2 year, P= 0.46). Among donor factors studied, only cold ischemic time >24 hours identified recipients of donors > or =55 years at risk for graft loss. Compared to recipients of donors <55 years, recipients of donors > or =55 years established a lower initial GFR (42 vs. 56 mL/min/1.73 m(2), P < 0.0001), and had less stable GFR in the first post-transplant year (-1.5 vs. -0.6 mL/min/1.73 m(2), P <.0001). Recipients from donors > or =55 years with initial GFR > or =50 mL/min/1.73 m(2) and no drop GFR during the first post-transplant year had graft survival that was superior to that of donors <55 years with either initial GFR <50 mL/min/1.73 m(2) or a drop in GFR during the first post-transplant year. CONCLUSION: Donors > or =55 years are a valuable resource. Despite improvements in immunosuppression, rejection, and delayed graft function, the projected increase in long-term graft survival among recipients of donors <55 years was not shared among recipients of donors > or =55 years. Recipients of donors > or =55 years had lower initial GFR, and less stable GFR during the first post-transplant year. Limiting cold ischemic time to <24 hours may improve outcomes among recipients of donors > or =55 years. Future studies to maximize initial GFR and minimize early loss of GFR in recipients of donors > or =55 years may lead to improved outcomes from deceased donors > or =55 years. 相似文献
116.
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118.
Armatys SA Cheng L Gardner TA Sundaram CP 《Journal of endourology / Endourological Society》2005,19(8):997-999
A 21-year-old woman presented with flank pain, and an abdominal and pelvic CT scan demonstrated a left 7.4-cm simple cyst superior to the left kidney. She underwent laparoscopic cyst decortication complicated by a diaphragmatic injury and pneumothorax. The final pathology report described a retroperitoneal pulmonary sequestration (RPS). Urologists need to consider RPS in the differential diagnosis of a retroperitoneal cyst because of the associated morbidity of hemorrhage during surgical excision. With the widespread use abdominal imaging techniques, more cases of RPS are likely to be identified and referred for laparoscopic management. 相似文献
119.
Brandon WP Troyer JL Sundaram R Schoeps N Sun Y Walsh BJ 《Journal of health care for the poor and underserved》2005,16(4):760-779
This case-study (n=41,969) of voluntary switching among Mecklenburg County, North Carolina Medicaid managed care plans showed a low switching rate of 14.5 per 100 member-years over 33 months, or 5.3 averaged annually. Population, plan and plan characteristics, claims and telephone survey data were examined to better understand this important behavioral measure. Switching in Medicaid managed care, which is little studied, is contrasted with the extensive literature on middle class switching. Policy implications included the suitability of Medicaid populations for managed care and the need for more research on switching and disenrollment and the Medicaid innovation of neutral health benefits advising. 相似文献
120.