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91.
Alcohol and tobacco use commonly co-occur, with at least 90% of those with an alcohol problem also using tobacco. Thus, 3 years ago when we discovered higher rate of late deaths due to lung and oropharyngeal cancer in patients who had received a transplant for alcoholic liver disease (ALD), we hypothesized that these patients were continuing to expose themselves to tobacco after liver transplantation (post-LTX) and that this behavior was increasing their risk for cancer. We subsequently began a prospective investigation of post-LTX tobacco use in patients having undergone LTX for ALD (n = 172). For 33 recipients we had data starting from our first assessment at 3 months post-LTX and for this subgroup we report on the details of the timing of tobacco use resumption and the redevelopment of nicotine addiction. We found that on average more than 40% are smoking across all time periods. ALD recipients resume smoking early post-LTX, increase their consumption over time, and quickly become tobacco dependent. These data highlight an underrecognized serious health risk for these patients and demonstrate our need for more stringent clinical monitoring and intervention for tobacco use in the pre- and post-LTX periods.  相似文献   
92.

Background

The impact of newer breast imaging technologies and genetic testing on the detection of breast cancer in women age 40 and younger remains unknown.

Methods

A records review identified 628 women age 40 and younger diagnosed with breast cancer from 1996 to 2008. Patient and tumor characteristics, means of diagnosis, imaging results, and genetic testing were examined.

Results

Tumors were first detected by self-examination in 71%, with a median invasive tumor size of 2.0 cm. Imaging performed at or after diagnosis visualized most tumors; mammography visualized 86%, magnetic resonance imaging (MRI) visualized 96%, and mammography plus MRI visualized more than 98% of tumors. For 81% of patients, the mammogram at diagnosis was their first mammogram. Although 50% had a family history of breast or ovarian cancer, few underwent genetic testing before their cancer diagnosis; 61 of 247 (25%) ultimately tested had a BRCA mutation.

Conclusions

Better use of genetic testing, mammography, and MRI could improve breast cancer detection in young women.  相似文献   
93.
HIF-1α has been shown to be a central mediator of cellular response to hypoxia. The role it plays after ischemic injury to the immature femoral head is unknown. The purpose of this study was to determine the region of the femoral head affected by hypoxia following ischemic injury to the immature femoral head and to determine the site of HIF-1α activation and revascularization. We hypothesize that the epiphyseal cartilage, rather than the bony epiphysis, is the site of HIF-1α activation following ischemic osteonecrosis and that the epiphyseal cartilage plays an important role in the revascularization process.Materials and methodsFemoral head osteonecrosis was surgically induced in 56 immature pigs. Hypoxyprobe staining, cell viability assay, HIF-1α western blot, RT-qPCR of HIF-1α, VEGF, VEGFR2, and PECAM, and micro-CT assessments of microfil-infused femoral heads were performed.ResultsSevere hypoxia was present in the bony epiphysis and the lower part of the epiphyseal cartilage following ischemia. In the bony epiphysis, extensive cell death and tissue necrosis was observed with degradation of proteins and RNAs which precluded further analysis. In the epiphyseal cartilage, the loss of cell viability was limited to its deep layer with the remainder of the cartilage remaining viable. Furthermore, the cartilage from the ischemic side showed a significant increase in HIF-1α protein level and HIF-1α expression. VEGF expression in the cartilage was dramatically and significantly increased at 24 h, 2 and 4 weeks (p < 0.05 for all) with 5 to 10 fold increase being observed on the ischemic side compared to the normal side. PECAM and VEGFR2 expressions in the cartilage were both significantly decreased at 24 h but returned to the normal levels by 2 and 4 weeks, respectively. Micro-CT showed revascularization of the cartilage on the ischemic side with the vessel volume/total volume equaling the normal side by 4 weeks.ConclusionsAcute ischemic injury to the immature femoral head induced severe hypoxia and cell death in the bony epiphysis and the deep layer of the epiphyseal cartilage. Viable chondrocytes in the superficial layer of the epiphyseal cartilage showed HIF-1α activation and VEGF upregulation with subsequent revascularization occurring in the cartilage.  相似文献   
94.
Introduction. The present case study is an analysis of the effect of compression socks on hemostatic activation following a marathon in a female endurance athlete found to be heterozygous for the coagulation factor V (F5 1691 G>A [Arg>Gln rs6025/560]) risk allele that predisposes one to a genetically inherited disorder of blood clotting, Factor V Leiden. Methods. Markers for coagulation and fibrinolysis were obtained 24 h prior to (PRE), immediately after (FINISH) and 24 h after (POST) completion of two marathons: the first in which the runner was not wearing compression socks, and the second in which the runner wore compression socks throughout the race. Results. Compression socks worn during a marathon appeared to lower the overall impact on hemostasis as well as clot formation in this particular athlete as evidenced by lower t-PA (–56%), TAT (–63%) and D-dimer (–30%). Conclusions. Hemostatic activation may be lower with the use of compression socks, and thus may be effective for preserving hemostasis in endurance athletes at risk.  相似文献   
95.
This study reports on 60 cases of suicide in Londonderry, Northern Ireland from January 2000 to December 2005. The research focused on a number of factors associated with the occurrence of suicide. These included age, gender, employment status, method used and possible predisposing factors. Additionally, the seasonality of occurrence was also investigated. Notably, over the period of the study, the number of suicides almost doubled. The results demonstrated that 83.3% of suicides were male. The largest proportion of these, over one third, occurred in men between the ages 21 and 30 years. This high rate of young male suicides was in marked contrast to any other group. The most frequent method of suicide recorded in this study was hanging (55%). The next most frequent methods were drowning (25%) and overdose (13.3%). Three times as many males (6) overdosed compared to females.  相似文献   
96.
Macula densa (MD) cells detect changes in distal tubular sodium chloride concentration ([NaCl](L)), at least in part, through an apical Na:2Cl:K co-transporter. This co-transporter may be a site for regulation of tubuloglomerular feedback (TGF), and recently angiotensin II (Ang II) was shown to regulate the MD Na:2Cl:K co-transporter. In addition, nitric oxide (NO) produced via neuronal NO synthase (nNOS) in MD cells attenuates MD-TGF signaling. This study investigated [NaCl](L)-dependent MD-NO production, the regulation of co-transporter activity by NO, and the possible interaction of NO with Ang II. MD cell Na(+) concentration ([Na(+)](i)) and NO production were measured using sodium-binding benzofuran isophthalate and 4-amino-5-methylamino-2',7'-difluorescein diacetate, respectively, using fluorescence microscopy. Na:2Cl:K co-transport activity was assessed as the initial rate of increase in [Na(+)](i) when [NaCl](L) was elevated from 25 to 150 mM. 10(-4) M 7-nitroindazole, a specific nNOS blocker, significantly increased by twofold the initial rate of rise in [Na(+)](i) when [NaCl](L) was increased from 25 to 150 mM, indicating co-transporter stimulation. There was no evidence for an interaction between the stimulatory effect of Ang II and the inhibitory effect of NO on co-transport activity, and, furthermore, Ang II failed to alter MD-NO production. NO production was sensitive to [NaCl](L) but increased only when [NaCl](L) was elevated from 60 to 150 mM. These studies indicate that MD-NO directly inhibits Na:2Cl:K co-transport and that NO and Ang II independently alter co-transporter activity. In addition, generation of MD-NO seems to occur only at markedly elevated [NaCl](L), suggesting that NO may serve as a buffer against high rates of MD cell transport and excessive TGF-mediated vasoconstriction.  相似文献   
97.
Inhibitors of apoptosis proteins in prostate cancer cell lines   总被引:34,自引:0,他引:34  
BACKGROUND: The caspases are the central executioners of apoptosis. The inhibitors of apoptosis proteins (IAPs) are a family of recently described caspase inhibitors. We hypothesised that tumor resistance to apoptosis could be due in part to IAP expression. METHODS: The expression of NAIP, cIAP-1, cIAP-2, XIAP, and survivin was investigated in the prostate cancer cell lines LNCaP, PC3, and DU145. RNase protection assays and Western blotting were used to assess RNA and protein expression. Apoptotic susceptibility was determined using etoposide and assessed by propidium iodide (PI) DNA incorporation using flow cytometry. RESULTS: DU145 and PC3 cells were more resistant to apoptosis than LNCaP cells. All the IAPs were identified in the cell lines with variation in IAP expression between different cell types. Immunohistochemistry demonstrated cIAP-1 expression in PC3 cells was nuclear, while the expression of cIAP-2 and XIAP was perinuclear. Growing LNCaP cells in charcoal-stripped or androgen-supplemented medium resulted in no alteration in IAP expression. CONCLUSIONS: This study characterises the expression of IAP in three of the most commonly used prostate cancer cells. IAP may make an important contribution to apoptotic resistance in patients with prostate cancer.  相似文献   
98.
AIM: The longevity of peritoneal dialysis (PD) is limited by technique failure and patient mortality. The authors assessed the influence of baseline and time-averaged fluid removal on patient, technique and death-censored technique survival. METHODS: Peritoneal and total fluid removal was measured 1 month after commencing PD, then 6 monthly, in 225 incident patients (mean age 55.3+/-15.8 years, 52% male). A Cox proportional hazards model regression analysis was performed to identify variables independently predictive of technique and patient survival. RESULTS: Seventy (31.9%) patients were transferred to haemodialysis and 39 (17.63%) died. Technique survival was greatest in the middle tertile of baseline total fluid removal (mean survival time 3.5 vs 2.5 and 2.2 years for the lower and upper tertiles, respectively, log rank 6.5, P=0.039). The middle tertile of both baseline and time-averaged total fluid removal were significant predictors of PD survival (adjusted hazard ratio (HR) 0.476, 95% CI 0.286-0.795, P=0.005 relative to the upper tertile and HR 0.573, 95% CI 0.350-0.939, P=0.027 for baseline and time-averaged, respectively). Other significant variables on multivariate analysis were body mass index (HR 1.044 per kg/m2, 95% CI 1.005-1.084, P=0.028), creatinine (HR 0.999 per micromol, 95% CI 0.998-1.000, P=0.048) and residual Kt/V (HR 0.418, 95% CI 0.233-0.747, P=0.003). Patient survival was not affected by fluid removal. CONCLUSION: Patients with moderate total fluid removal both at baseline and throughout their PD career have improved technique survival. Attention should be paid to optimizing total fluid removal.  相似文献   
99.
OBJECTIVE: To investigate an optimized glucose-insulin-potassium (GIK) solution regimen as an alternate myocardial protective strategy in off-pump coronary artery bypass graft (OP-CAB) surgery and as a supplement to conventional coronary artery bypass graft (CABG) surgery using cardiopulmonary bypass (CPB). DESIGN: Prospective, randomized, placebo-controlled. SETTING: Single institution, cardiothoracic specialty hospital. PARTICIPANTS: Forty-four patients scheduled for elective multivessel coronary artery surgery using either conventional CPB (n = 22) or OP-CAB techniques (n = 22). INTERVENTIONS: Preischemic, ischemic, and postischemic administration of GIK solution was carried out, optimally dosed to ensure nonesterified fatty acid (NEFA) suppression, and supplemented with magnesium, a glycolytic enzymatic cofactor. MEASUREMENTS AND MAIN RESULTS: GIK solution therapy reduced plasma NEFA levels (p < 0.001) in OP-CAB surgery and CPB groups but failed to affect the incidence of non-Q wave perioperative myocardial infarction, incidence of postoperative atrial fibrillation, incidence of postoperative infection, reduction in creatinine clearance, or duration of postoperative intensive care unit or hospital length of stay. After adjusting for GIK solution therapy, OP-CAB surgery resulted in significantly less ischemic injury (troponin I >15 microg/L, 19.0% v 91.3%; p = 0.0001) and reduced postoperative infections (14.3% v 43.5%; p = 0.049). CONCLUSION: GIK solution therapy achieved NEFA suppression and an insignificant trend toward reduced biochemical parameters of ischemic injury in OP-CAB surgery and CPB groups, but no major clinical benefit (perioperative myocardial infarction, intensive care unit length of stay, or hospital length of stay) was shown after elective CABG surgery in low-risk patients. Compared with CPB, OP-CAB surgery significantly reduced ischemic injury and postoperative infections.  相似文献   
100.
BACKGROUND: On antigenic stimulation, CD4 T cells generally proliferate more readily than CD8 T cells. The purpose of the present experiments was to determine whether nitric oxide (NO) might differentially modulate CD4 vs. CD8 T-cell proliferation. METHODS: Various concentrations of C57BL/6 iNOS +/+ and -/- bone marrow (BM)-derived antigen presenting cells (APC) (obtained by culture in granulocyte-macrophage colony-stimulating factor [GM-CSF] and interleukin [IL]-4) were cultured with purified BALB/c CD4 or CD8 T cells. RESULTS: Proliferation of CD4 T cells was similar in the presence of both NO synthase (iNOS) +/+ and -/- APC, whereas CD8 T cell proliferation was inhibited at the higher concentrations of iNOS +/+ dendritic cells (DC), coincident with increased levels of NO in the culture supernatant. Analysis of cytokine levels revealed that more interferon (IFN)-gamma, a potent inducer of NO synthesis in many cell types, was present in CD8 T cell than in CD4 T-cell-APC cultures. Addition of IFN-gamma to CD4 T-cell-APC cultures resulted in induction of NO synthesis and inhibition of proliferation at higher levels of NO than that required to inhibit CD8 T cell proliferation. However, CD4 T-cell proliferation was moderately inhibited in the presence of lipopolysaccharide (LPS)-stimulated CD11c DC, coincident with production of IFN-gamma and induction of NO synthesis. CONCLUSIONS: These findings indicate that CD8 T-cell proliferation can be inhibited by lesser amounts of APC-derived NO than is necessary to inhibit CD4 T cell proliferation. NO synthesis was not initiated in CD4 T cell-DC cultures unless costimulatory molecules were up-regulated and IFN-gamma was produced.  相似文献   
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