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991.
The challenge of heart transplantation in patients with situs inversus is reconstruction of the systemic venous return. Herein we have presented 2 cases of complex congenital heart disease with atriovisceral situs inversus. Both of the patients shared many common cardiac anomalies, such as a single ventricle, a single AV valve with severe regurgitation, and severe pulmonary stenosis. We completed the venous connection in 2 different ways. In the first case, the donor inferior vena cava (IVC) was anastomosed to the recipient left-sided IVC directly, making the heart slightly counterclockwise rotated. In the second case, the IVC venous reconnection was accomplished by a composite conduit made of recipient right atrium. 相似文献
992.
Beath S Pironi L Gabe S Horslen S Sudan D Mazeriegos G Steiger E Goulet O Fryer J 《Transplantation》2008,85(10):1378-1384
Intestinal transplant wait-list mortality is higher than for other organ transplants. The objective of this workshop was to identify the main problems contributing to high mortality in adults and children candidates for intestinal transplantation and provide recommendations on how to correct them. OUTCOME: To facilitate this, 63 relevant articles identified from the medical literature from 1987 to 2007 were reviewed. Consensus was achieved on several important definitions relevant to this review. For children and adults on parenteral nutrition (PN) the main mortality risk factors were identified as were the main risks of mortality for those on the waiting list for intestinal transplants. RECOMMENDATIONS: (1) Primary care givers managing intestinal failure patients should establish a link with an intestinal failure programs early and collaboration with intestinal failure programs should be initiated for patients whose PN requirements are anticipated to be more than 50% 3 months after initiating PN; (2) intestinal failure programs should include both intestinal rehabilitation and intestinal transplantation or have active collaborative relationships with centers performing intestinal transplantation; (3) National registries for intestinal failure patients should be established and organizations that provide home PN solutions should be expected to participate. CONCLUSION: There are many unresolved issues in adults and children with PN dependent intestinal failure. To address these, a key recommendation of this group is to establish national intestinal failure databases that can support multicenter studies and lead to the adoption of universally accepted standards of patient care with the goal of improving outcomes in all long-term intestinal failure patients including those requiring intestinal transplantation. 相似文献
993.
Mottram PL Leong D Crimeen-Irwin B Gloster S Xiang SD Meanger J Ghildyal R Vardaxis N Plebanski M 《Molecular pharmaceutics》2007,4(1):73-84
Previous studies compared uptake by dendritic cells (DC) of 20, 40, 100, 200, 500, 1000, and 2000 nm beads in vivo. When beads were used as antigen carriers, bead size influenced antibody responses and induction of IFN-gamma-producing CD4 and CD8 T cells. Beads of 40-50 nm were taken up preferentially by DC and induced particularly strong immunity. Herein, we examine immunity induced by minute differences in nanobead size, specifically within a narrow viral-sized range (20, 40, 49, 67, 93, 101, and 123 nm), to see if bead carrier size influenced the induction of type 1 or type 2 cells as demonstrated by the production of IFN-gamma or IL-4. In vivo uptake by DC was assessed for selected sizes in this range. Responses to whole ovalbumin (OVA) or the OVA-derived CD8 T cell peptide epitope (SIINFEKL) were tested. After one immunization with beads-OVA, IFN-gamma responses to both OVA and SIINFEKL were significantly better with 40 and 49 nm beads than other sizes, while, in contrast, IL-4 responses to OVA were higher after immunization with OVA conjugated to larger beads (93, 101, and 123 nm). Thus IFN-gamma induction from CD8 T cells was limited to 40-49 nm beads, while CD4 T cell activation and IL-4 were induced by 93-123 nm beads-OVA. After two immunizations, there were comparable high levels of IFN-gamma produced with 40 and 49 beads and IL-4 reactivity was still higher for larger beads (93, 101, 123 nm). Production of IgG1 was seen across the full range of bead sizes, increasing after two immunizations. Since protection against respiratory syncytial virus (RSV) depends on strong IFN responses, while IL-4 responses are reported to cause asthma-like symptoms, immunization with RSV antigens on the 49 nm carrier beads could provide the basis for a suitable vaccine. When the 49 nm beads were conjugated to RSV proteins G88 (surface) or M2.1 (internal capsid), one immunization with G88 induced high levels of IFN-gamma and low levels of IL-4. IL-4 increased with two immunizations. Beads-M2.1 induced only moderate levels of IFN-gamma and low titer antibody after two immunizations. Mice vaccinated once with G88-conjugated 49 nm beads and challenged intranasally with RSV strain A2 subtype showed reduced viral titers and recovered from weight loss more rapidly than mice immunized with M2.1-conjugated 49 nm beads or naive control mice. These results show that precise selection of nanobead size for vaccination can influence the type 1/type 2 cytokine balance after one immunization, and this will be useful in the development of effective vaccines against common human pathogens such as RSV. 相似文献
994.
Saslow D Castle PE Cox JT Davey DD Einstein MH Ferris DG Goldie SJ Harper DM Kinney W Moscicki AB Noller KL Wheeler CM Ades T Andrews KS Doroshenk MK Kahn KG Schmidt C Shafey O Smith RA Partridge EE;Gynecologic Cancer Advisory Group Garcia F 《CA: a cancer journal for clinicians》2007,57(1):7-28
The American Cancer Society (ACS) has developed guidelines for the use of the prophylactic human papillomavirus (HPV) vaccine for the prevention of cervical intraepithelial neoplasia and cervical cancer. These recommendations are based on a formal review of the available evidence. They address the use of prophylactic HPV vaccines, including who should be vaccinated and at what age, as well as a summary of policy and implementation issues. Implications for screening are also discussed. 相似文献
995.
We describe the use of nitric oxide as an oxygen-sparing strategy in the context of prior bleomycin exposure. A 27-year-old male, previously treated with bleomycin for a testicular germ cell tumour presented with severe acute respiratory distress syndrome on the second postoperative day following an extensive retroperitoneal dissection. The mechanism of bleomycin toxicity and potential benefits of nitric oxide in this situation are considered. 相似文献
996.
997.
Navratilova E Waite S Stropova D Eaton MC Alves ID Hruby VJ Roeske WR Yamamura HI Varga EV 《Molecular pharmacology》2007,71(5):1416-1426
Agonist-mediated desensitization of the opioid receptors is thought to function as a protective mechanism against sustained opioid signaling and therefore may prevent the development of opioid tolerance. However, the exact molecular mechanism of opioid receptor desensitization remains unresolved because of difficulties in measuring and interpreting receptor desensitization. In the present study, we investigated deltorphin II-mediated rapid desensitization of the human delta opioid receptors (hDOR) by measuring guanosine 5'-O-(3-[(35)S]thio)-triphosphate binding and inhibition of cAMP accumulation. We developed a mathematical analysis based on the operational model of agonist action (Black et al., 1985) to calculate the proportion of desensitized receptors. This approach permits a correct analysis of the complex process of functional desensitization by taking into account receptor-effector coupling and the time dependence of agonist pretreatment. Finally, we compared hDOR desensitization with receptor phosphorylation at Ser363, the translocation of beta-arrestin2, and hDOR internalization. We found that in Chinese hamster ovary cells expressing the hDOR, deltorphin II treatment leads to phosphorylation of Ser363, translocation of beta-arrestin2 to the plasma membrane, receptor internalization, and uncoupling from G proteins. It is noteworthy that mutation of the primary phosphorylation site Ser363 to alanine had virtually no effect on agonist-induced beta-arrestin2 translocation and receptor internalization yet significantly attenuated receptor desensitization. These results strongly indicate that phosphorylation of Ser363 is the primary mechanism of hDOR desensitization. 相似文献
998.
999.
Balasubramanian SP Cox A Cross SS Higham SE Brown NJ Reed MW 《International journal of cancer. Journal international du cancer》2007,121(5):1009-1016
Vascular endothelial growth factor-A (VEGF-A) plays an important role in tumour angiogenesis and cancer progression. VEGF gene variation may influence VEGF levels and therefore cancer susceptibility and progression. We studied the role of VEGF single nucleotide polymorphisms and haplotypes in breast cancer susceptibility and severity. We also studied the relationships of VEGF SNPs with circulating VEGF levels in healthy volunteers and protein expression in breast cancers. Single nucleotide polymorphisms (SNPs) in the regulatory regions of the VEGF gene were genotyped by high throughput methods in approximately 500 breast cancer cases and 500 appropriate controls. Haplotype frequencies were inferred using methods based on the Expectation Maximisation algorithm. The effect of VEGF genotypes on serum and plasma VEGF levels were studied in another cohort of healthy individuals. A semi-quantitative assessment of VEGF protein expression on tissue micro arrays (TMA) constructed from approximately 300 breast cancer samples was performed and compared with VEGF genotypes and with histopathological parameters and survival in breast cancer. The -460T/+405C/-7C/936C haplotype in the VEGF gene was found to be associated with decreased breast cancer risk (p = 0.029). The -7C>T polymorphism may influence overall breast cancer survival (p = 0.027). Individual polymorphisms however did not affect breast cancer susceptibility. There was no association between the individual polymorphisms and circulating VEGF levels in healthy volunteers and VEGF expression on the breast cancer micro array. VEGF expression in breast cancers was however associated with high grade (p = 0.002) and ER negative tumours (p = 0.03). 相似文献
1000.
Lissowska J Gaudet MM Brinton LA Chanock SJ Peplonska B Welch R Zatonski W Szeszenia-Dabrowska N Park S Sherman M Garcia-Closas M 《International journal of cancer. Journal international du cancer》2007,120(12):2696-2703
Epidemiological evidence suggests that intake of folate and other B-vitamins and genetic variants in the one-carbon metabolism pathway could influence the risk of breast cancer. Previous studies have focused on 2 polymorphisms in the methylenetetrahydrofolate gene (MTHFR A222V and E429A); however, findings are inconclusive. In a large population-based case-control study in Poland (2,386 cases, 2,502 controls), we investigated the association between breast cancer risk and 13 polymorphisms in 6 one-carbon metabolism genes (MTHFR, MTR, MTRR, CBS, SHMT1 and SLC19A1). Data suggested an association between a nonsynonymous change in the gene coding for methionine synthase (MTR D919G) and reduced breast cancer risk: OR (95% CI) = 0.84 (0.73-0.96) and 0.85 (0.62-1.15) for heterozygous and homozygote variant genotypes, respectively, compared with common homozygotes; p-trend = 0.01, false discovery rate = 0.14. We found no significant associations between other variants and breast cancer risk, including MTHFR A222V or E429A. Meta-analyses including published studies of MTHFR A222V (8,330 cases and 10,825 controls) and E429A (6,521 cases and 8,515 controls) supported the lack of an overall association; however, studies suggested an increase in risk among premenopausal women. In conclusion, this report does not support a substantial overall association between the evaluated polymorphisms in the one-carbon metabolism pathway and breast cancer risk. 相似文献