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A prospective study to evaluate the incidence of herpes zoster (HZ) as an immune restoration disease in patients with AIDS during highly active antiretroviral therapy (HAART) was conducted in a series of 115 patients diagnosed with AIDS initiated on HAART between 1 January 2000 and 31 July 2001. Of these, a single dermatomal HZ episode occurred in 14 (12%) patients within one and 15 months of HAART (median eight months). The HZ patients were similar to the non-HZ patients in age, sex, and HIV transmission risk factor, but had a more advanced disease. Compared with the baseline values, the viral loads significantly (P<0.01) decreased, while the mean CD4+ T-cell counts increased by almost four-fold (P<0.01) in both groups at the time of the HZ episode (or equivalent in non-HZ), but remained below 400/mL in the HZ patients. HZ during HAART is an immunopathological consequence of the improvement of the host immuneresponse, correlating with the beginning of immune restoration.  相似文献   
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Plasma concentration of atazanavir (ATV) may be reduced when coadministered with tenofovir (TDF) or proton pump inhibitors. Boosting ATV exposure with ritonavir (r) may make it possible to overcome these drug interactions. However, jaundice and loss of the metabolic advantages of ATV are more frequent using ATV/r than ATV alone. Herein, we assessed whether therapeutic drug monitoring (TDM) could make it possible to identify the subset of patients in whom removal of ritonavir could be attempted without risk of suboptimal plasma ATV exposure and subsequent virological failure. A total of 56 patients with undetectable plasma HIV-RNA under a stable triple regimen containing ATV 300/100 mg qd were switched to ATV 400 mg qd. Plasma ATV concentrations were measured using a reliable high-performance liquid chromatography method. Median plasma ATV C(min) fell from 880 to 283 ng/ml (p = 0.03) after removal of ritonavir. While all patients on ATV/r showed ATV plasma concentrations within therapeutic values (IC(min) above 150 ng/ml) before switching, four patients (7%) fell below this threshold after switching to ATV 400 mg qd. However, only one of this group experienced virological failure at week 24 of follow-up. TDF was part of the antiretroviral regimen in all four cases. From a total of 29 (52%) patients on ATV/r showing grade 3-4 hyperbilirubinemia, only 7 (12%) remained on it upon switching to ATV 400 mg qd (p < 0.001). Patients with complete viral suppression under ATV/r 300/100 mg qd may benefit from switching to ATV 400 mg qd guided by TDM, which may make it possible to minimize adverse events without compromising antiviral efficacy in most cases.  相似文献   
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In circulating lymphocytes from patients with non-insulin-dependent diabetes mellitus (NIDDM) subnormal pyruvate dehydrogenase (PDH) activity returns to normal following patient treatment with sulfonylurea (gliclazide*, 80 mg twice daily/5 weeks). Moreover, in vitro in cells from diabetic patients exposed to insulin at 50 μU/mL PDH activation also occurs; in cells of controls the same happens for insulin at 5 μU/mL, whereas at 50 μU/mL inhibition takes place. Therefore, the low PDH activity in cells of NIDDM patients might be caused by defective insulin control on the enzyme and its recovery in gliclazide-treated patients by drug-mediated removal of the defect. The validity of the hypothesis was verified in this study where cells of NIDDM patients before and after gliclazide treatment were exposed, in vitro, to insulin at 5 and 50 μU/mL and then tested for PDH activity. In such conditions, the profile of PDH behavior in treated patients was no longer comparable to that in untreated patients but closer to that in euglycemic controls, thus supporting the view that the recovery of PDH activity in NIDDM patients following gliclazide treatment might be the expression of an additional effect that the drug would have in these patients, aimed to renew cell responsiveness to insulin.  相似文献   
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PURPOSE: Preoperative chemoradiation therapy is used widely in the treatment of rectal cancer. The predictive value of response to neoadjuvant remains uncertain. We retrospectively evaluated the impact of response to preoperative and, specifically, of T-level downstaging, nodal downstaging, and complete pathologic response after chemoradiation therapy on oncologic outcome of patients with locally advanced rectal cancer. METHODS: There were 88 patients with ultrasound Stage T3/T4 midrectal (n = 37) and low rectal (n = 51) cancers (63 males; mean age 62.6 years). All patients were treated by preoperative 5-fluorouracil-based chemotherapy and pelvic radiation followed by surgical resection in six weeks or longer (56 sphincter-preserving resections). RESULTS: T-level downstaging after neoadjuvant treatment was demonstrated in 36 (41 percent) of 88 patients, and complete pathologic response was observed in 16 (18 percent) of the 88. Of the 42 patients with ultrasound-positive nodes, 27 had no evidence of nodal involvement on pathologic evaluation (64 percent). The overall response rate (T-level downstaging or nodal downstaging) was 51 percent. At a median follow-up of 33 months, 86.4 percent of patients were alive. The overall recurrence rate was 10.2 percent (three patients had local and six had metastatic recurrences). Patients with T-level downstaging and complete pathologic response were characterized by significantly better disease-free survival (P = 0.03, P = 0.04) and better overall survival (P = 0.07, P = 0.08), according to Wilcoxons test comparing Kaplan-Meier survival curves. None of the patients with complete pathologic response developed recurrence or died during the follow-up period. CONCLUSION: T-level downstaging and complete pathologic response after preoperative chemoradiation therapy followed by definitive surgical resection for advanced rectal cancer resulted in decreased recurrence and improved disease-free survival. Advanced rectal cancers that undergo T-level downstaging and complete pathologic response after chemoradiation therapy may represent subgroups that are characterized by better biologic behavior.  相似文献   
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Purpose of Review

This review synthesizes the utility of measuring migraine triggers for the purpose of forecasting future headache attacks. The nature of forecasting models, headache triggers as inputs to such models, and how these trigger exposures can be measured for forecasting are reviewed. A critical evaluation of the existing forecasting models in the context of their potential application for preemptive treatment is considered.

Recent Findings

A substantial pool of candidate trigger factors could be considered in the creation of forecasting models. However, because mechanistic information about causal factors that precede a migraine attack is not well understood, and such factors are difficult to measure, empirical models that are based on trigger factors that are merely associated with the onset of headache activity are likely to be the focus of forecasting efforts in the near future. Of such factors, stress has considerable empirical support and has been used to successfully forecast future headache attacks within individuals over time. However, at present, existing models possess only modest levels of discrimination and lack strong resolution in generated predictions.

Summary

Current headache forecasting models represent an important first step in accurately predicting future headache activity. However, to utilize these models in a preemptive treatment paradigm where the risk of headache is treated prior to the actual experience of pain, these models must achieve greater precision with good calibration and generate predictions that are clinically actionable by individuals in their real-time home environments.
  相似文献   
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