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31.
Dane Christina Daoud MD Elena M. S. Cartagena MD MSc Katherine J. P. Schwenger RD PhD Nicha Somlaw MD Leah Gramlich MD Scott Whittaker MD David Armstrong MD Brian Jurewitsch PharmD Matreyi Raman MD Donald R. Duerksen MD James D. McHattie MD Johane P. Allard MD 《JPEN. Journal of parenteral and enteral nutrition》2022,46(2):348-356
32.
Lisa J Frigati Katalin A Wilkinson Stanzi le Roux Karryn Brown Sheena Ruzive Leah Githinji Wonita Petersen Sabine Belard Mark F Cotton Landon Myer Heather J Zar 《Journal of the International AIDS Society》2021,24(3)
IntroductionThere are limited data on Tuberculosis (TB) in adolescents with perinatally acquired HIV (APHIV). We examined the incidence and determinants of TB infection and disease in the Cape Town Adolescent Antiretroviral Cohort (CTAAC).MethodsYouth between nine and fourteen years on antiretroviral therapy (ART) for more than six months in public sector care, and age‐matched HIV‐negative adolescents, were enrolled between July 2013 through March 2015 and followed six‐monthly. Data were censored on 31 October 2018. Symptom screening, chest radiograph, viral load, CD4 count, QuantiFERON (QFT) and sputum for Xpert MTB/RIF, microscopy, culture and sensitivity were performed annually. TB infection was defined by a QFT of >0.35 IU/mL. TB diagnosis was defined as confirmed (culture or Xpert MTB/RIF positive) or unconfirmed (clinical diagnosis and started on TB treatment). Analyses examined the incidence and determinants of TB infection and disease.ResultsOverall 496 HIV+ and 103 HIV‐negative participants (median age at enrolment 12 years (interquartile range, IQR 10.6 to 13.3) were followed for a median of 3.1 years (IQR 3.0 to 3.4); 50% (298/599) were male. APHIV initiated ART at median age 4.4 years (IQR 2.1 to 7.6). At enrolment, 376/496 (76%) had HIV viral load <40 copies/mL, median CD4 count was 713 cells/mm3 and 179/559 (32%) were QFT+, with no difference by HIV status (APHIV 154/468, 33%; HIV negative 25/91, 27%; p = 0.31). The cumulative QFT+ prevalence was similar (APHIV 225/492, 46%; 95%CI 41% to 50%; HIV negative 44/98, 45%; 95% CI 35% to 55%; p = 0.88). APHIV had a higher incidence of all TB disease than HIV‐negative adolescents (2.2/100PY, 95% CI 1.6 to 3.1 vs. 0.3/100PY, 95% CI 0.04 to 2.2; IRR 7.36, 95% CI 1.01 to 53.55). The rate of bacteriologically confirmed TB in APHIV was 1.3/100 PY compared to 0.3/100PY for HIV‐negative adolescents, suggesting a fourfold increased risk of developing TB disease in APHIV despite access to ART. In addition, a positive QFT at enrolment was not predictive of TB in this population.ConclusionsHigh incidence rates of TB disease occur in APHIV despite similar QFT conversion rates to HIV‐negative adolescents. Strategies to prevent TB in this vulnerable group must be strengthened. 相似文献
33.
De Simone R Glombitza G Vahl CF Albers J Meinzer HP Hagl S 《The Annals of thoracic surgery》1999,67(2):494-499
BACKGROUND: Color Doppler echocardiography is a standard technique for assessing mitral regurgitation before and after mitral valvuloplasty. Mitral valve prolapse produces complex eccentric jet flows that cannot be visualized and measured by two-dimensional color Doppler echocardiography. The aim of this study was to evaluate the clinical impact of three-dimensional color Doppler echocardiography, a new technique developed at our institution, for assessing mitral regurgitation. METHODS: Forty-five patients with mitral regurgitation underwent intraoperative transesophageal echocardiography and three-dimensional Doppler data acquisition. The grade of mitral regurgitation was assessed by angiography. The jet areas were calculated by planimetry from conventional color Doppler; the jet volumes were obtained by three-dimensional Doppler data. RESULTS: New patterns of mitral regurgitant flows were recognized according to the origin, direction, and spatial spreading into the left atrium. Conventional jet areas failed to separate the groups of patients with different degrees of regurgitation, whereas the jet volumes were able to divide patients with different regurgitation grades. No significant correlation was found between jet area and angiographic grading (r = 0.63, p = NS). Jet volumes were significantly correlated to angiography (r = 0.89, p < 0.001). CONCLUSIONS: Three-dimensional color Doppler echocardiography revealed new patterns of regurgitant flow and allowed a more accurate semiquantitative assessment of complex asymmetrical regurgitant jets. 相似文献
34.
Positron emission tomography in the clinical staging of patients with Stage I and II testicular germ cell tumors 总被引:3,自引:0,他引:3
OBJECTIVES: To evaluate the accuracy of fluorodeoxyglucose positron emission tomography (PET) compared with computed tomography (CT) staging in patients with Stage I and II testicular germ cell tumors (GCTs). METHODS: From January 1995 to July 1997, in 37 patients with clinical Stage (CS) I (n = 25) and CS II (n = 12) GCT (24 nonseminomas, 13 seminomas), PET and CT were compared in the initial staging. After PET, the patients with nonseminomatous GCT were staged surgically by retroperitoneal lymph node dissection and the patients with seminomatous GCT were followed up clinically. RESULTS: Correct staging by PET was achieved in 34 of 37 patients compared with correct CT staging in 29 of 37 patients. Of 10 metastatic lesions, 7 and 4 were detected by PET and CT, respectively. PET did not show false-positive signals. PET was unable to detect vital cancer with a maximal diameter less than 0.5 cm or teratoma at any size. CONCLUSIONS: PET was useful for detecting viable tumor in lesions that are visible on CT scan and, thus, it may omit false-positive CS II lesions. However, PET was not able to identify mature teratoma. In this study, PET did not improve the staging in patients with CS I tumor. 相似文献
35.
Choice of endpoints in antiplatelet trials: which outcomes are most relevant to stroke patients? 总被引:2,自引:0,他引:2
Albers GW 《Neurology》2000,54(5):1022-1028
The relative efficacies of different antiplatelet agents for stroke prevention are unclear because of differences in clinical trial design, a lack of direct comparisons between individual agents, and differences in the choice of primary endpoints. Individual endpoints in a clinical trial are often combined into a single primary endpoint cluster. Theoretically, a combined endpoint may reduce the sample size required to demonstrate significant benefits of an effective therapy. However, unless all components of a composite endpoint are affected in the same direction and to a similar degree, their inclusion may not provide the anticipated increase in statistical power. In fact, the use of a combined endpoint may lead to an underestimate of therapeutic benefits when patients at high risk for one particular endpoint are studied. For patients with stroke or TIA, the single outcome of stroke is particularly important because these patients have a higher risk of recurrent stroke than any other vascular outcome during the initial years after a stroke. Because of the low incidence of myocardial infarction (MI) in stroke trials, the inclusion of MI in the primary endpoint will usually have minimal influence on trial outcome, and antiplatelet therapy has not been shown to be beneficial in preventing nonvascular death. Chance variations in the incidence of MI or death may detract from the benefit of the agent for stroke prevention when it is included in a combined endpoint. The benefit of antiplatelet therapies for patients with recent cerebrovascular events is determined most accurately if stroke alone is chosen as the primary endpoint. 相似文献
36.
37.
Selfotel in acute ischemic stroke : possible neurotoxic effects of an NMDA antagonist 总被引:19,自引:0,他引:19
Davis SM Lees KR Albers GW Diener HC Markabi S Karlsson G Norris J 《Stroke; a journal of cerebral circulation》2000,31(2):347-354
BACKGROUND AND PURPOSE: Based on neuroprotective efficacy in animal models, we evaluated the N-methyl D-aspartate antagonist Selfotel in patients with ischemic stroke, after doses up to 1.5 mg/kg were shown to be safe in phase 1 and phase 2a studies. METHODS: Two pivotal phase 3 ischemic stroke trials tested the hypothesis, by double-blind, randomized, placebo-controlled parallel design, that a single intravenous 1.5 mg/kg dose of Selfotel, administered within 6 hours of stroke onset, would improve functional outcome at 90 days, defined as the proportion of patients achieving a Barthel Index score of >/=60. The trials were performed in patients aged 40 to 85 years with acute ischemic hemispheric stroke and a motor deficit. RESULTS: The 2 trials were suspended on advice of the independent Data Safety Monitoring Board because of an imbalance in mortality after a total enrollment of 567 patients. The groups were well matched for initial stroke severity and time from stroke onset to therapy. There was no difference in the 90-day mortality rate, with 62 deaths (22%) in the Selfotel group and 49 (17%) in the placebo-treated group (RR=1.3; 95% CI 0.92 to 1.83; P=0.15). However, early mortality was higher in the Selfotel-treated patients (day 30: 54 of 280 versus 37 of 286; P=0.05). In patients with severe stroke, mortality imbalance was significant throughout the trial (P=0.05). CONCLUSIONS: Selfotel was not an effective treatment for acute ischemic stroke. Furthermore, a trend toward increased mortality, particularly within the first 30 days and in patients with severe stroke, suggests that the drug might have a neurotoxic effect in brain ischemia. 相似文献
38.
39.
Stephen F Stanziale Henrik Petrowsky Prasad S Adusumilli Leah Ben-Porat Mithat Gonen Yuman Fong 《Clinical cancer research》2004,10(9):3225-3232
PURPOSE: The antitumor efficacy of a herpes simplex virus (HSV)-1 oncolytic virus depends on the cytotoxic effect of the virus, but also on viral replication and spread within the tumor. Apoptosis is considered a defense mechanism of infected cells that minimizes the spread of viral progeny by limiting cellular production of virus. We sought to determine whether oncolytic HSV-1 infection induces apoptosis in neighboring, uninfected cells and whether manipulation of apoptosis can increase viral replication and cytotoxicity. EXPERIMENTAL DESIGN: NV1066 is an oncolytic HSV-1 mutant that contains the marker gene for enhanced green fluorescent protein. OCUM human gastric cancer cells were infected with NV1066 in vitro and inspected for apoptosis by Hoechst and terminal deoxynucleotidyltransferase-mediated nick end labeling staining and for infection by expression of green fluorescence. RESULTS: A significant increase in apoptosis was seen in cells infected by NV1066. More interestingly, a significant percentage (10%) of uninfected cells also proceeded to apoptosis. After NV1066 infection, cells were also treated with N-acetylcysteine (NAC), an inhibitor of apoptosis. By day 4 after infection, 2.7x more NV1066 was produced in cells exposed to NAC than in those not exposed to NV1066 (P = 0.04). NAC also increased tumor kill when administered with virus. CONCLUSIONS: These data suggest that NV1066 induces apoptosis in uninfected cocultured cells, potentially hindering propagation of viral progeny and concomitant tumor kill. Inhibition of apoptosis may improve the efficacy of oncolytic HSV-1 therapy. 相似文献
40.
Predictors of occult metastasis in clinical stage I nonseminoma: a systematic review. 总被引:3,自引:0,他引:3
Yvonne Vergouwe Ewout W Steyerberg Marinus J C Eijkemans Peter Albers J Dik F Habbema 《Journal of clinical oncology》2003,21(22):4092-4099
PURPOSE: Patients with clinical stage I nonseminomatous testicular germ cell tumor should ideally receive adjuvant therapy only when they are at high risk for occult metastasis. We aimed to quantify the importance of predictors for occult metastasis by performing a systematic review of the relevant literature. In addition, we reviewed published multivariable models and risk-adapted treatment policies. PATIENTS AND METHODS: We identified 23 publications between 1979 and 2001, reporting a total of 2,587 patients. Twenty-nine percent of the patients (759 of 2,587 patients) had occult metastases, which was diagnosed either at retroperitoneal lymph node dissection (n = 193) or during follow-up (n = 566). Odds ratios (OR) were pooled using meta-analysis techniques. RESULTS: The presence of vascular invasion of the primary tumor cells had the strongest effect (OR, 5.2; 95% CI, 4.0 to 6.8). Immunohistochemical staining of the primary tumor cells with the MIB-1 monoclonal antibody showing proliferative activity was a promising predictor (OR, 4.7; 95% CI, 2.0 to 11). Intermediate effects were found for embryonal carcinoma in the primary tumor (OR, 2.9; 95% CI, 2.0 to 4.4) and a high pathologic stage of the tumor (OR, 2.6; 95% CI, 1.8 to 3.8). Size of the primary tumor and age of the patient had weaker though also statistically significant associations with occult metastasis. Until now, multivariable models often included vascular invasion and embryonal carcinoma with one or two weaker predictors. None of the published risk-adapted treatment policies included MIB-1 staining. CONCLUSION: Several strong predictors for occult metastasis were identified. A risk-adapted treatment policy should be developed that incorporates all relevant predictors so that adjuvant therapy is targeted better to those with occult metastases. 相似文献