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61.
Socioeconomic status,access to triple therapy,and survival from HIV-disease since 1996 总被引:3,自引:0,他引:3
Wood E Montaner JS Chan K Tyndall MW Schechter MT Bangsberg D O'Shaughnessy MV Hogg RS 《AIDS (London, England)》2002,16(15):2065-2072
BACKGROUND: In the era before highly active antiretroviral therapy (HAART), socioeconomic status was associated with survival from HIV disease. We have explored socioeconomic status, access to triple therapy (HAART), and mortality in the context of a universal healthcare system. METHODS: We evaluated 1408 individuals who initiated double or triple therapy between 1 August 1996 and 31 December 1999, and were followed until 31 March 2000. Cumulative HIV-related mortality rates were estimated using Kaplan-Meier methods and Cox proportional hazards regression. RESULTS: In the overall Cox model, we found that adherence [risk ratio (RR) 0.83; per 10% increase], CD4 cell count (RR 1.53; per 100 cell decrease), and lower socioeconomic status (RR 2.19; high versus low), were associated with HIV-related mortality. However, socioeconomic status was not significant among patients prescribed triple therapy in a stratified analysis, or in a sub-analysis restricted to patients prescribed HAART in the initial regimen. When we investigated if inequitable access to HAART by socio-economic status could explain the discrepancy, we found that persons in the lower socio-economic strata were less likely to be prescribed triple therapy even after adjustment for clinical characteristics. CONCLUSION: In a universal healthcare system, socioeconomic status was strongly associated with HIV-related mortality. When we investigated possible explanations for this association, we found that individuals of lower socioeconomic status were less likely to receive triple therapy after adjustment for clinical characteristics. Our findings highlight the need for the monitoring of therapeutic guidelines to ensure equitable access, as treatment strategies are updated. 相似文献
62.
C T Noguchi D A Torchia A N Schechter 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(10):4936-4940
13C/1H magnetic double-resonance spectroscopy has been used to quantitate the amount of polymerized hemoglobin S in deoxygenated gels at 30 degrees C, for samples whose hemoglobin concentration range from 21 to 32 g/dl. Scalar- and dipolar-decoupled spectra and a 13C proton-enhanced dipolar-decoupled spectrum were recorded for each sample as was a scalar-decoupled spectrum for a matching oxyhemoglobin S control. The difference between the oxyhemoglobin S and deoxyhemoglobin S scalar-decoupled spectra was used to determine the polymer fraction, and this value was compared with the polymer fraction determined by using ultracentrifugation sedimentation on the same sample (assuming a two-phase model). The polymer fraction value determined by uncorrected sedimentation averaged 0.15 more than the value obtained from NMR. The discrepancy between the two techniques was largely removed when the analysis of the sedimentation data included a correction for depletion of hemoglobin in the supernatant or sol phase due to sedimentation of free molecules. The best fit to both the sedimentation and NMR data was obtained by using a solubility of deoxyhemoglobin S at 30 degrees C of 17.3 +/- 1 g/dl. These results indicate that the NMR techniques, which do not require separation of the sample into a sol phase and a pellet phase, provide quantitative information about the deoxyhemoglobin S polymer and will be useful for studies of sickle erythrocytes. 相似文献
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Hydroxyurea nitrosylates and activates soluble guanylyl cyclase in human erythroid cells 总被引:1,自引:0,他引:1
Hydroxyurea, a drug widely used for treating myeloproliferative diseases, has also been approved for the treatment of sickle cell disease by raising fetal hemoglobin (HbF). We have shown that nitric oxide (NO) and the soluble guanylyl cyclase (sGC) pathways are involved in hydroxyurea induction of HbF levels in erythroid progenitor cells (EPCs). We demonstrate now that during erythroid differentiation, endothelial NO synthase mRNA and protein levels decline steadily, as does the production of NO derivatives and cyclic adenosine monophosphate (cAMP) levels, but guanosine 3',5'-cyclic monophosphate (cGMP) levels are stable. Hydroxyurea increased intracellular cGMP levels and cAMP levels in EPCs. The NO donor, DEANONOate, induced much higher cGMP levels, but reduced cAMP levels. Hydroxyurea (1 mM) induced production of approximately 45 pM cGMP/minute/ng of purified sGC, similar to induction by 1 muM DEANONOate. We found that hydroxyurea and ProliNONOate produced iron-nitrosyl derivatives of sGC. Thus, we confirm that hydroxyurea can directly interact with the deoxy-heme of sGC, presumably by a free-radical nitroxide pathway, and activate cGMP production. These data add to an expanding appreciation of the role of hydroxyurea as an inducer of the NO/cGMP pathway in EPCs. These mechanisms may also be involved in the cytostatic effects of hydroxyurea, as well as the induction of HbF. 相似文献
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68.
Meir Schechter MD Matan Fischer MD Ofri Mosenzon MD 《Diabetes, obesity & metabolism》2022,24(6):969-982
Patients with type 2 diabetes (T2D) are at increased risk for hospital admissions, and acute hospitalizations are associated with a worse prognosis. However, outcomes related to all-cause hospital admissions (ACHAs) were often overlooked in trials that demonstrated the cardiovascular and kidney benefits of sodium-glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RAs). This review includes a contemporary literature summary of emerging data regarding the effects of SGLT2 inhibitors and GLP-1RAs on ACHAs. The role of SGLT2 inhibitors in preventing ACHAs was shown in exploratory investigations of several randomized controlled trials (RCTs) and was further supported by real-world evidence (RWE). However, the association between GLP-1RA use and lower ACHA risk was mainly shown through RWE, with minimal available RCT data. We also discuss the advantages and challenges of studying ACHAs. Finally, we propose an easily memorized (“ABCDE” acronym) clinical approach to evaluating T2D status and treatment in admitted patients, as they transition from hospital to community care. This systematic approach may assist clinicians in recognizing possible pitfalls in T2D management, thereby preventing subsequent hospitalizations and improving patient prognoses. While acute admission can sometimes be perceived as a management failure, it should also be viewed as an opportunity to take action to prevent the next hospitalization. 相似文献
69.
M D Schechter 《General pharmacology》1991,22(5):889-893
1. Para-chlorophenylalanine (p-CPA), a competitive inhibitor of the serotonin (5-HT) synthesis enzyme tryptophan hydroxylase, was administered to rats at a dosage (100 mg/kg daily for 3 days) that depletes 5-HT. 2. Different groups of these rats were previously trained to discriminate the interoceptive stimuli produced by amphetamine, cathinone, 3,4-methylenedioxymethamphetamine (MDMA), N-ethyl-3,4-methylenedioxyamphetamine (MDE), fenfluramine or yohimbine, and the effect of p-CPA pretreatment upon their discriminative performance was compared with the effect of saline (control) pretreatment. 3. p-CPA was shown to have no effect upon the dopaminergically-mediated stimuli produced by the stimulants amphetamine and cathinone or upon yohimbine performance. 4. p-CPA significantly decreased discriminative performance with the serotonergic releasing drugs MDMA, MDE and fenfluramine. This decrease in discriminative performance returned to pre-p-CPA (criterion) levels at a time (9-12 days) when 5-HT has been reported to replete to normal brain concentrations. 5. It is concluded that p-CPA pretreatment lowers brain 5-HT and, in turn, significantly decreases the ability of rats to discriminate centrally active drugs whose interoceptive cueing stimuli are mediated by 5-HT neurons. 相似文献
70.
Steven A. Signs PhD Howard I. Dickey-White MD Vincent W. Vanek MD Steven Perch MS Martin D. Schechter PhD Albert T. Kulics PhD 《The American journal of emergency medicine》1996,14(7):665-670
The purpose of this investigation was to document the clinical presentation of emergency department (ED) patients who tested positive for concurrent cocaine (COC) and ethanol (EtOH) use and the incidence of cocaethylene (CE) formation in this study population. Four study groups were evaluated: (1) drug-free, (2) EtOH-only, (3) COC-only, and (4) COC plus EtOH. CE was detected in plasma or urine specimens in 88% of the COC/EtOH-positive patients, and correlated directly with plasma COC and its metabolite benzoylecognine. Blood pressure and body temperature did not vary across study groups. COC/EtOH-positive patients displayed a significantly higher mean respiratory rate while the EtOH-only study group had an elevated mean heart rate. No significant differences were detected with respect to cardiac and neurological complaints between study groups. Trauma complaints in the drug-positive groups were more frequent than the incidence reported in the drug-free population. COC/EtOH-positive patients had the greatest percentage of trauma complaints (34.6%). Nearly half of the patients who tested positive for CE cited trauma as the primary reason for reporting to the ED. We conclude that ED patients who have concurrently used COC and EtOH are more closely associated with presentations related to traumatic injury than to those related to toxicologic complications. 相似文献