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21.
Modification of the current allocation system for donor livers in the United States to incorporate recipient serum sodium concentration ([Na]) has recently been proposed. However, the impact of this parameter on posttransplantation mortality has not been previously examined in a large risk-adjusted analysis. We assessed the effect of recipient [Na] on the survival of all adults with chronic liver disease who received a first single organ liver transplant in the UK and Ireland during the period March 1, 1994 to March 31, 2005 (n=5,152) at 3 years, during the first 90 days, and beyond the first 90 days, adjusting for a wide range of recipient, donor, and graft characteristics. Compared to those with normal [Na] (135-145 meq/L; n=3,066), severely hyponatremic recipients ([Na]<130 meq/L, n=541), had a higher risk-adjusted mortality at 3 years (hazard ratio [HR] 1.28; 95% confidence interval [CI], 1.04-1.59; P<0.02). The excess mortality was, however, confined to the first 90 days (HR 1.55; 95% CI, 1.18-2.04; P<0.002) with no significant difference thereafter. This was also true for hypernatremic recipients ([Na]>45 meq/L, n=81), who had an even greater risk-adjusted mortality compared to normonatremic recipients (overall: HR 1.85; 95% CI, 1.25-2.73; P<0.002; 90 days: HR 1.12; 95% CI, 0.55-2.29; P=0.8), whereas mildly hyponatremic recipients ([Na] 130-134 meq/L, n=1,127) had similar risk-adjusted mortality to those with normal [Na] at the same time points. In conclusion, recipient [Na] is an independent predictor of death following liver transplantation. Attempts to correct the [Na] toward the normal reference range are an important aspect of pretransplantation management.  相似文献   
22.
AIM: Ectopic pregnancy is conventionally managed by laparoscopic salpingectomy. Electrocautery has been used widely to secure hemostasis during salpingectomy. However, this method is associated with a risk of thermal injury to the visceral organs. Endoloop, a pre-tied suture used in laparoscopic surgery may be an alternative treatment tool and its potential use in the management of ectopic pregnancy is explored here. Our study aims to compare the effectiveness of the endoloop technique to electrocautery during laparoscopic salpingectomy for tubal pregnancy. METHODS: A prospective randomized controlled study was conducted over 24 months at the Hospital Universiti Kebangsaan Malaysia. One hundred and two patients with tubal pregnancy were randomized into two treatment groups: those treated with endoloop and those treated with electrocautery during laparoscopic salpingectomy. RESULTS: The use of an endoloop was associated with a shorter operating time (48.85 min +/- 21.019 vs 61.14 min +/- 22.603, 95% CI -20.864 to -3.724), lower visual analog scores for postoperative pain at day 1 (2.02 +/- 0.960 vs 2.74 +/- 0.828, 95% CI -1.074 to -0.368) and day 7 (0.85 +/- 0.802 vs 1.44 +/- 0.837, 95% CI -0.916 to -0.272), and lesser total analgesia required by patients at day 7 after the operation (7.65 +/- 6.119 vs 15.32 +/- 8.326, 95% CI -10.529 to -4.804). There was no significant difference in the ability to secure hemostasis when both techniques were compared. Duration of hospitalization (2.37 days +/- 0.817 vs 2.34 days +/- 0.519, 95% CI -0.245 to -0.296) and interval from operation to discharge were similar. CONCLUSION: The endoloop appeared to be as effective as electrocautery and is a safe alternative to electrocautery for laparoscopic salpingectomy in tubal pregnancy.  相似文献   
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Tumor necrosis factor-alpha-induced changes in insulin-producing beta-cells   总被引:1,自引:0,他引:1  
The migration of macrophages and lymphocytes that produce cytokines such as tumor necrosis factor-alpha (TNF-alpha) causes beta-cell death, leading to type 1 diabetes. Similarly, in type 2 diabetes, the adipocyte-derived cytokines including TNF-alpha are elevated in the circulation, causing inflammation and insulin resistance. Thus, the studies described in this article using TNF-alpha are relevant to furthering our understanding of the pathogenesis of diabetes mellitus. We used RINr1046-38 (RIN) insulin-producing beta-cells, which constitutively express calbindin-D(28k), to characterize the effect of TNF-alpha on apoptosis, replication, insulin release, and gene and protein expression. Western blots of TNF-alpha-treated RIN cells revealed a decrease in calbindin-D(28k). By ELISA, TNF-alpha-treated beta-cells had 47% less calbindin-D(28k) than controls. In association with the decline in calbindin-D(28k), TNF-alpha treatment of RIN cells led to a 73% greater increase in changes in intracellular calcium concentration (Delta[Ca(2+)](i)) in TNF-alpha-treated cells as compared to that in control RIN cells upon treatment with 50 mM KCl; caused a greater increase in the [Ca(2+)](i) following the addition of 5.5 microM ionomycin; increased by more than threefold the apoptotic rate, expressed as the percentage of TUNEL-positive nuclei to total nuclei; decreased the rate of cell replication by 36%; and increased and decreased selectively the expression of specific genes as determined by microarray analysis. The subcellular localizations of Bcl-2, an antiapoptotic protein, and Bax, a proapoptotic protein, within RIN cells were altered with TNF-alpha treatment such that the two were colocalized with mitochondria in the perinuclear region. We conclude that the proapoptotic action of TNF-alpha on beta-cells is manifested via decreased expression of calbindin-D(28k) and is mediated at least in part by [Ca(2+)](i).  相似文献   
26.
Autosomal recessive nonsyndromic deafness is one of the most frequent forms of inherited hearing impairment. Over 30 autosomal recessive nonsyndromic hearing loss loci have been mapped, and 15 genes have been isolated. Of the over 30 reported autosomal recessive nonsyndromic hearing loss (NSHL) loci, the typical phenotype is prelingual non-progressive severe to profound hearing loss with the exception of DFNB8, which displays postlingual onset and DFNB13, which is progressive. In this report we describe a large inbred kindred from a remote area of Pakistan, comprising six generations and segregating autosomal recessive nonsyndromic prelingual deafness. DNA samples from 24 individuals were used for genome wide screen and fine mapping. Linkage analysis indicates that in this family the NSHL locus, (DFNB35) maps to a 17.54 cM region on chromosome 14 flanked by markers D14S57 and D14S59. Examination of haplotypes reveals a region that is homozygous for 11.75 cM spanning between markers D14S588 and D14S59. A maximum two-point LOD score of 5.3 and multipoint LOD score of 7.6 was obtained at marker D14S53. The interval for DFNB35 does not overlap with the regions for DFNA9, DFNA23 or DFNB5.  相似文献   
27.
Characteristic cytogenetic aberrations are found in the various histopathological designations of meningioma. These aberrations range from the loss of 22q in histologically benign tumors to complex hypodiploid karyotypes in atypical and malignant tumors. This progression is characterized by increasing chromosome loss and instability, with a critical step being the loss of 1p. We report a detailed cytogenetic investigation of chromosome aberrations in a series of 88 meningiomas using Giemsa banding and multicolor spectral karyotyping (SKY). Clonal chromosome aberrations were identified in 46 (52%) tumors by G banding. Thirty-five tumors showing complex chromosome aberrations not fully characterized by G banding were subsequently reanalyzed by SKY. The SKY technique refined the G-band findings in 18 (51%) of the tumors on which it was applied. The most common features of cytogenetic progression in the complex karyotypes were chromosome arm-specific losses relating to the formation of deletions and dicentric chromosomes involving 1p. Part or all of 1p was lost in 19 tumors. Five tumors showed evidence for the loss of 1p in a progressive step-wise series of telomeric fusions involving the formation of unstable intermediates. Five recurring dicentric chromosomes were identified, including dic (1;11)(p11;p11), dic(1;12)(p12 approximately p13;p11), dic(1;22)(p11;q12 approximately q13), dic(7;19)(p11;p11), and dic(19;22)(p11 approximately p13;q11 approximately q13). These findings provide evidence that telomeric fusions play a role in the formation of clonal deletions, dicentrics, and unbalanced translocations of 1p. The loss of 1p has possible diagnostic and prognostic implications in the management of meningioma.  相似文献   
28.
Pathologic processes involving the urachus are usually related to inflammatory or sinofistular conditions. Neoplasms rarely arise within this structure, and when they do occur, they are typically epithelial, with mucinous adenocarcinoma being the most common. Mesenchymal lesions, both benign and malignant, have rarely been described in this location. We report the case of a 66-year-old white man who presented with a primary urachal malignant fibrous histiocytoma and died of metastatic disease 20 months after the initial diagnosis. This is an unusual case of malignant fibrous histiocytoma arising in a urachal remnant.  相似文献   
29.
In this study, we investigated whether levels of interleukin-12 (IL-12) and IL-18 in plasma are associated with severe malarial anemia outcomes in an area of holoendemicity in western Kenya. We compared plasma IL-12 and IL-18 levels in six groups of children grouped into the categories aparasitemic, asymptomatic, mild malaria, high-density uncomplicated malaria (UC), moderate malarial anemia (MMA), or severe malarial anemia (SMA). IL-12 levels were significantly reduced in children with SMA (P < 0.05) but not in other groups compared to children in the aparasitemic control group. IL-18, a cytokine known to be critical for the induction of gamma interferon along with IL-12, was produced more frequently (70%) in children with UC (P = 0.06) than in children in the aparasitemic control group (32%). However, in the SMA group the IL-18 response rate declined to 30%, which was similar to that in the aparasitemic control group, which showed a 32% response rate. This finding suggests that the IL-18 response may be impaired in children with SMA. In summary, the results from this study support the hypothesis that impairment of IL-12 and/or IL-18 response may contribute to the development of severe malarial anemia in areas of holoendemicity for malaria.  相似文献   
30.
Aims—To elucidate the implications of allelic loss on chromosome 10 in the malignant progression of human gliomas.  相似文献   
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