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61.

Background:

There is no prospective randomized data comparing laparoscopic to open hepatectomy. This study compared short- and long-term outcomes in patients undergoing hepatectomy for colorectal metastases (CRM), who were suitable for either laparoscopic or open surgery.

Methods:

Data were prospectively collected from consecutive patients undergoing hepatic resection of CRM at a single centre (1987–2007). Patients who were suitable for laparoscopic resection (Group 1) were compared with patients whose tumour characteristics would best be considered for open resection (Group 2).

Results:

Out of 1152 hepatectomies, 266 (23.1%) were deemed suitable for a laparoscopic approach. The median (IQR) number of metastases was greater in Group 2 [2(1–20) vs. 1(1–10), P < 0.001], as was the mean (SD) tumour size [5.3(3.6) cm vs. 3.3(1.2) cm, P < 0.001]. The median (IQR) operation time [210 (70) min vs. 240 (90) min, P < 0.001] and blood loss [270 (265) ml vs. 355 (320) ml, P < 0.001] were less in Group 1. There was no difference in length of stay, morbidity or mortality. Patients in Group 2 had a higher R1 resection rate (14.9%) compared with Group 1 (4.5%, P < 0.001) and lower 5-year survival (37.8% vs. 44.2%, P= 0.005).

Discussion:

Current criteria for laparoscopic hepatectomy selects patients who have more straight-forward surgery, with less risk of an involved resection margin and better long-term survival, compared with patients unsuited to a laparoscopic approach. Clearly defined criteria for laparoscopic hepatectomy are essential to allow meaningful analysis of outcomes and the results of unrandomized series of laparoscopic hepatectomies must be interpreted with caution.  相似文献   
62.

Background and purpose:

Chemokines orchestrate neutrophil recruitment to inflammatory foci. In the present study, we evaluated the participation of three chemokines, KC/CXCL1, MIP-2/CXCL2 and LIX/CXCL5, which are ligands for chemokine receptor 2 (CXCR2), in mediating neutrophil recruitment in immune inflammation induced by antigen in immunized mice.

Experimental approach:

Neutrophil recruitment was assessed in immunized mice challenged with methylated bovine serum albumin, KC/CXCL1, LIX/CXCL5 or tumour necrosis factor (TNF)-α. Cytokine and chemokine levels were determined in peritoneal exudates and in supernatants of macrophages and mast cells by elisa. CXCR2 and intercellular adhesion molecule 1 (ICAM-1) expression was determined using immunohistochemistry and confocal microscopy.

Key results:

Antigen challenge induced dose- and time-dependent neutrophil recruitment and production of KC/CXCL1, LIX/CXCL5 and TNF-α, but not MIP-2/CXCL2, in peritoneal exudates. Neutrophil recruitment was inhibited by treatment with reparixin (CXCR1/2 antagonist), anti-KC/CXCL1, anti-LIX/CXCL5 or anti-TNF-α antibodies and in tumour necrosis factor receptor 1-deficient mice. Intraperitoneal injection of KC/CXCL1 and LIX/CXCL5 induced dose- and time-dependent neutrophil recruitment and TNF-α production, which were inhibited by reparixin or anti-TNF-α treatment. Macrophages and mast cells expressed CXCR2 receptors. Increased macrophage numbers enhanced, while cromolyn sodium (mast cell stabilizer) diminished, LIX/CXCL5-induced neutrophil recruitment. Macrophages and mast cells from immunized mice produced TNF-α upon LIX/CXCL5 stimulation. Methylated bovine serum albumin induced expression of ICAM-1 on mesenteric vascular endothelium, which was inhibited by anti-TNF-α or anti-LIX/CXCL5.

Conclusion and implications:

Following antigen challenge, CXCR2 ligands are produced and act on macrophages and mast cells triggering the production of TNF-α, which synergistically contribute to neutrophil recruitment through induction of the expression of ICAM-1.  相似文献   
63.
The purpose of the study was to test the hypothesis that single nucleotide polymorphisms (SNPs) within interleukin (IL)-18, TNF-alpha, IL-6 and IL-10 gene promoter regions are risk factors for cognitive decline in healthy octogenarians, and to isolate the strongest inflammatory biomarkers of cognitive function in the peripheral blood. The Wechsler Adult Intelligence Scale was administered to 112 individuals at ages 80 and 85. An IL-18 haplotype was an independent risk factor of poor Performance IQ. The TNF-308GA genotype was related to individual declines in Verbal IQ, and the IL-10-592 CC genotype was related to better Verbal IQ at the age of 80. Circulating levels of TNF-alpha, sTNFRs, and IL-6 were negatively correlated with IQ at age 85 and less strongly to IQ at age 80 with activation of the TNF system as the strongest biomarker. In conclusion, SNPs related to high proinflammatory or low anti-inflammatory activity are independent risk factors of reduced cognitive function in octogenarians. Only the IL-18 haplotype was associated with inflammation in the peripheral blood and only with regard to circulating TNF-alpha.  相似文献   
64.
BACKGROUND: Approximately 1% of all cases of Alzheimer's disease are inherited autosomal dominantly, and to date, three causative genes have been found, the Presenilin 1 (PSEN1) gene, the Presenilin 2 (PSEN2) gene and the Amyloid precursor protein (APP) gene. We describe atypical phenotypic features in a family with a pathogenic APP gene mutation and discuss possible explanations for these atypical features. METHODS AND RESULTS: We report a family with a history of dementia compatible with autosomal dominant transmission. The disease course in the proband was not typical for Alzheimer's disease as the diagnosis was preceded by 8 years of an isolated amnesia. Further, the proband had epilepsy with complex partial seizures and central degenerative autonomic failure as determined by clinical physiology. Sequencing the three known causative Alzheimer genes revealed a pathogenic missense mutation, APP Thr714Ala (the Iranian mutation). CONCLUSIONS: The atypical clinical phenotype with long prodromal phase, autonomic failure and seizures in this new proband with the APP Thr714Ala mutation illustrates the clinical heterogeneity in families with identical pathogenic mutations.  相似文献   
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In 22 hemodialysis patients, during a dialysis session, the solute removal index (SRI) for urea obtained from the use of a partial spent dialysate collection method was compared with that derived from the use of a total spent dialysate collection technique. The partial spent dialysate collection method was used to harvest a small representative sample of the total spent dialysate. The volumes of spent dialysate collected by the partial and the total spent dialysate collection methods were 1.7 +/- 0.4 L and 129.6 +/- 15.3 L, respectively. The total amount of urea nitrogen removed by dialysis as estimated by the partial spent dialysate collection method was similar to that determined by the total spent dialysate collection approach. As a result, the SRI value for urea obtained by the partial spent dialysate collection method (namely, 63% +/- 8%) correlated very well (r = 0.95, P < 0.001) with that derived by the total spent dialysate collection technique (namely, 62% +/- 8%). Our data suggest that it is feasible to use a simple partial spent dialysate collection method to obtain SRI results in patients treated with hemodialysis.  相似文献   
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