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91.
Maddalena Gaeta Emanuele Rausa Alexis E. Malavazos Luigi Bonavina Cornelius M. Smuts Cristian Ricci 《Obesity surgery》2018,28(4):900-906
Background
Type II obesity represents a major pandemic and public health threat in high-income countries. Type II obesity increases the risk of all-cause and specific-cause mortality, and it is widely acknowledged that bariatric surgery represents the only effective therapeutic option in these patients. The aim of the present study was to estimate US population attributable risk for all-cause and cause-specific mortality in type II obese subjects undergoing weight loss as resulting from bariatric surgery alone and supplemented with behavioral intervention.Methods
The American National Health and Nutrition Examination Survey linked to the US death registry updated to 2011 was used to estimate type II obesity prevalence and all-cause and specific cause of death for type II obese adults undergoing weight loss. Multivariate adjusted proportional hazard Cox models were used to estimate mortality risks. Statistical analyses were performed on the most updated version of the database (June 2017).Results
A monotone positive trend for type II obesity was observed during the period 1999–2014 (p < 0.001). According to trend analysis, the rate of type II obesity in US adults is expected to rise up to 8.5%. Two- to sevenfold increased risk of all-cause and specific-cause mortality was observed for type II obese participants when compared to type I obese and overweight participants. Population attributable risk for all-cause and specific-cause mortality for type II obese subjects undergoing weight loss was ranging between 6 and 34%.Conclusions
Bariatric surgery supplemented with behavioral intervention can result in a relevant reduction of mortality if extensively applied to the US population.92.
Glutathione metabolism and antioxidant enzymes in patients affected by nonalcoholic steatohepatitis 总被引:4,自引:0,他引:4
Nobili V Pastore A Gaeta LM Tozzi G Comparcola D Sartorelli MR Marcellini M Bertini E Piemonte F 《Clinica chimica acta; international journal of clinical chemistry》2005,355(1-2):105-111
BACKGROUND: Oxidative stress and accumulation of excessive fat in the liver may underlie the pathophysiology of nonalcoholic steatohepatitis (NASH). Given that glutathione blood metabolism may represent an indicator of tissue oxidative status, we analysed the blood profile of various forms of glutathione in children with NASH, and we evaluated the presence of systemic oxidative stress by calculating the oxidised/reduced glutathione ratio (GSSG/GSH). Furthermore, we analysed the catalytic activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione transferase (GST), and glutathione reductase (GR) in blood of patients. METHODS: Blood samples were obtained from 21 children with NASH and 28 controls. Total, reduced, oxidised, and protein-bound glutathione concentrations were determined by reversed-phase liquid chromatography with fluorescence detection. Antioxidant enzymes were spectrophotometrically assayed by using specific substrates. RESULTS: Our findings showed a 1.5-fold increase of GSSG in patients, resulting in a significant rise of the GSSG/GSH ratio. SOD, GPx, and GR activities were not significantly different in NASH respect to controls, whereas GST, which provides the second defence line against oxidative stress, was 17.8% increased. CONCLUSIONS: Our data demonstrate an impairment of glutathione metabolism and antioxidant enzyme activities in blood of patients with NASH, supporting a consistent role of free radical cytotoxicity in the pathophysiology of the disease. 相似文献
93.
Specificity of cytotoxic effector cells directed against trinitrobenzene sulfonate-modified syngeneic cells. Failure to recognize cell surface- bound trinitrophenyl dextran 下载免费PDF全文
PA Henkart A Schmitt-Verhulst GM Shearer 《The Journal of experimental medicine》1977,146(4):1068-1078
Mouse splenic lymphocytes and lymphoid tumor cells were modified with the trinitrophenyl (TNP) group either by treatment with trinitrobenzene sulfonate (TNBS) (which covalently modifies cell surface proteins) or with TNP stearoyl dextran (TSD) (which binds to the cell by noncovalent forces). These cell preparations were compared for their ability to: (a) sensitive syngeneic splenic lymphocytes leading to the generation of cytotoxic effector cells; (b) serve as lysable targets in a 4-h(51)Cr- release assay for effector cells generated in (a); and (c) act as blocking cells in the lysis of TNBS-medified targets lysed by TNP self effector cells generated in (a). In none of these three experimental systems did TSD-medified syngeneic spleen or H-2-matched tumor cells act either as a sensitizing immunogen or as a target antigen, despite the demonstration that quantitatively equivalent mounts of TNP were exposed on the cell surface in the TNBS- and TSD-modified cells. In contrast, TNBS-modified spleen cells sensitized syngeneic lymphocytes to generate effectors against TNBS-modified syageneic targets. Furthermore, TNBS- modified, H-2-matched cells served as specific lysable targets and as inhibiting cells for such effectors. These results indicate that the manner in which TNP is associated with the cell surface is important in the immunogenicity and antigenicity of hapten-modified syngeneic stimulating cells in generating H-2-associated cell-mediated lympholysis (CML) reactions. These findings raise the possibility that a covalent or at least a stable linkage with cell surface proteins (possibly H-2- controlled products) is important for immunological function. Furthermore, these observations do not favor the dual receptor model for H-2-restricted syngeneic CML if it is assumed in such a model that one receptor is specific for the TNP moiety and the second for unmodified self major histocompatibility products. 相似文献
94.
The present criteria for confirmation of human T-lymphotrophic virus types I and II (HTLV-I/II) infection in blood donors are based on seroreactivity to p24 (gag) and gp46 and/or gp61 (env) on Western blot (WB) and radioimmunoprecipitation assays (WB/RIPA). Any single band and other combinations are classified as indeterminate. This case report documents infection in a donor with a repeatedly indeterminate pattern. The blood donor was anti-HTLV-I/II positive on enzyme-linked immunoassay, and two sera taken 5 years apart were WB/RIPA-indeterminate (p19 and gp68 only). His donations in the interval were associated with transmission of HTLV-I to four of the six recipients available for study. Other recipients of blood from donors whose WB/RIPA results were indeterminate by present criteria should be examined to determine if additional patterns are at least occasionally associated with transmission. The likelihood that such donors are infected is important to those who are counseling them and making decisions concerning recipients of their bloody. 相似文献
95.
96.
Lentini S Gaeta R Tancredi F Savasta M La Monaca M Ciuffreda F Monaco F 《Journal of cardiac surgery》2009,24(1):57-58
Abstract We present a case where we repaired the aortic arch, by the transposition of the left carotid artery to the ascending aorta. A 52-year-old man presented to our department with a penetrating chest wound by a gunshot in the attempt of suicide. The aortic arch and the insertion of the left carotid artery were involved in the lesion. Through sternotomic approach, the aortic arch was repaired in extracorporeal circulation. Left carotid artery was transected to allow easier repair of the arch posterior wall involved in the lesion, and to reduce the danger of residual stenosis. Then, it was translocated to the ascending aorta by interposing a 7-mm Gore-Tex (W.L. Gore & Associates, Flagstaff, AZ, USA) conduit. The patient complicated renal failure and pneumonia in the postoperative period, but eventually he was discharged in good general conditions. 相似文献
97.
98.
GM Repetto ML Guzmán A Puga JF Calderón CP Astete M Aracena M Arriaza T Aravena P Sanz 《Clinical genetics》2009,76(5):465-470
Patients with chromosome 22q11 deletion syndrome exhibit significant phenotypic variability. Epidemiologic data suggest a higher incidence in Hispanics, but limited clinical information is available from Latin-American patients. We describe the clinical features of Chilean patients with 22q11 deletion syndrome and compare their findings with those reported in large European, Japanese and US series. Data were obtained from 208 patients from five medical centers. Mean age at diagnosis was 5.2 years, with a median of 2.3 years. Congenital heart defects were present in 59.6%, lower than other large series that averaged 75.8%. Palate abnormalities were present in 79%, higher than previous reports averaging 56%. Patients with congenital heart disease were diagnosed earlier (median 0.3 years of age) than those without heart defects (median 5.6 years) and had greater mortality attributable to the syndrome (9.8% vs 2.4%, respectively). The differences in frequencies of major anomalies may be due to growing awareness of more subtle manifestations of the syndrome, differences in clinical ascertainment or the presence of modifier factors. These observations provide additional data useful for patient counseling and for the proposal of health care guidelines. 相似文献
99.
S Pierno GM Camerino V Cippone J-F Rolland J-F Desaphy A De Luca A Liantonio G Bianco JD Kunic AL George Jr D Conte Camerino 《British journal of pharmacology》2009,156(8):1206-1215
Background and purpose:
Statins and fibrates can produce mild to life-threatening skeletal muscle damage. Resting chloride channel conductance (gCl), carried by the ClC-1 channel, is reduced in muscles of rats chronically treated with fluvastatin, atorvastatin or fenofibrate, along with increased resting cytosolic calcium in statin-treated rats. A high gCl, controlled by the Ca2+-dependent protein kinase C (PKC), maintains sarcolemma electrical stability and its reduction alters muscle function. Here, we investigated how statins and fenofibrate impaired gCl.Experimental approach:
In rats treated with fluvastatin, atorvastatin or fenofibrate, we examined the involvement of PKC in gCl reduction by the two intracellular microelectrodes technique and ClC-1 mRNA level by quantitative real time-polymerase chain reaction. Direct drug effects were tested by patch clamp analysis on human ClC-1 channels expressed in human embryonic kidney (HEK) 293 cells.Key results:
Chelerythrine, a PKC inhibitor, applied in vitro on muscle dissected from atorvastatin-treated rats fully restored gCl, suggesting the involvement of this enzyme in statin action. Chelerythrine partially restored gCl in muscles from fluvastatin-treated rats but not in those from fenofibrate-treated rats, implying additional mechanisms for gCl impairment. Accordingly, a decrease of ClC-1 channel mRNA was found in both fluvastatin-and fenofibrate-treated rat muscles. Fenofibric acid, the in vivo metabolite of fenofibrate, but not fluvastatin, rapidly reduced chloride currents in HEK 293 cells.Conclusions and implications:
Our data suggest multiple mechanisms underlie the effect of statins and fenofibrate on ClC-1 channel conductance. While statins promote Ca2+-mediated PKC activation, fenofibrate directly inhibits ClC-1 channels and both fluvastatin and fenofibrate impair expression of mRNA for ClC-1. 相似文献100.