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1.
Delayed contrast enhancement after injection of a gadolinium-chelate (Gd-chelate) is a reference imaging method to detect myocardial tissue changes. Its localization within the thickness of the myocardial wall allows differentiating various pathological processes such as myocardial infarction (MI), inflammatory myocarditis, and cardiomyopathies. The aim of the study was first to characterize benign myocarditis using quantitative delayed-enhancement imaging and then to investigate whether the measure of the extracellular volume fraction (ECV) can be used to discriminate between MI and myocarditis.In 6 patients with acute benign myocarditis (32.2 ± 13.8 year-old, subepicardial late gadolinium enhancement [LGE]) and 18 patients with MI (52.3 ± 10.9 year-old, subendocardial/transmural LGE), myocardial T1 was determined using the Modified Look-Locker Imaging (MOLLI) sequence at 3 Tesla before and after Gd-chelate injection. T1 values were compared in LGE and normal regions of the myocardium. The myocardial T1 values were normalized to the T1 of blood, and the ECV was calculated from T1 values of myocardium and blood pre- and post-Gd injection.In both myocarditis and MI, the T1 was lower in LGE regions than in normal regions of the left ventricle. T1 of LGE areas was significantly higher in myocarditis than in MI (446.8 ± 45.8 vs 360.5 ± 66.9 ms, P = 0.003) and ECV was lower in myocarditis than in MI (34.5 ± 3.3 vs 53.8 ± 13.0 %, P = 0.004).Both inflammatory process and chronic fibrosis induce LGE (subepicardial in myocarditis and subendocardial in MI). The present study demonstrates that the determination of T1 and ECV is able to differentiate the 2 histological patterns.Further investigation will indicate whether the severity of ECV changes might help refine the predictive risk of LGE in myocarditis.  相似文献   
2.
The purpose of our study was to determine the prevalence of protein-calorie malnutrition (PCM), ocular diseases, and vitamin A deficiency in preschool children selected at random in a rural zone of the groundnut belt of Senegal. The prevalence of PCM was 37.1% (95% CI 33.8-40.2%) according to the Waterlow classification, with a majority of stunting, and prevalence of hypovitaminosis A was estimated to be 11.4% (95% CI 9.3-13.5%) by using impression cytology. Furthermore, 19.4% (95% CI 15.8-22.0%) of the children might be defined at risk of deficiency. The prevalence of Bitot's spots was equal to 0.2% (95% CI 0.03-0.9%). A problem of PCM associated with a health-endangering vitamin A deficiency existed.  相似文献   
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BACKGROUND: Brachial artery reactivity (BAR), carotid intima-media thickness (IMT), and applanation tonometry for evaluation of total arterial compliance may provide information about preclinical vascular disease. We sought to determine whether these tests could be used to identify patients with coronary artery disease (CAD) without being influenced by their ability to identify those at risk for CAD developing. METHODS: We studied 100 patients and compared 3 groups: 35 patients with known CAD; 34 patients with symptoms and risk factors but no CAD identified by stress echocardiography (risk group); and 31 control subjects. BAR and IMT were measured using standard methods, and total arterial compliance was calculated by the pulse-pressure method from simultaneous radial applanation tonometry and pulsed wave Doppler of the left ventricular outflow. Ischemia was identified as a new or worsening wall-motion abnormality induced by stress. RESULTS: In a comparison between the control subjects and patients either at risk for developing CAD or with CAD, the predictors of risk for CAD were: age (P =.01); smoking history (P =.002); hypercholesterolemia (P =.002); and hypertension (P =.004) (model R = 0.82; P =.0001). The independent predictors of CAD were: IMT (P =.001); BAR (P =.04); sex (P =.005); and hypertension (P =.005) (model R = 0.80; P =.0001). CONCLUSION: IMT, BAR, and traditional cardiovascular risk factors appear to identify patients at risk for CAD developing. However, only IMT was significantly different between patients at risk for developing CAD and those with overt CAD.  相似文献   
5.
Forty consecutive adult patients under the age of 50 with acute non-lymphoblastic leukemia (ANLL) in first complete remission, underwent autologous bone marrow transplantation (ABMT) between March 1984 and April 1990. The conditioning regimen employed included cyclophosphamide and total body irradiation, followed by the administration of unpurged ABMT. The median time from diagnosis to transplant was 7 months (3-15 months), and the median time from complete remission to ABMT was 4 months (range 3-9 months). Twenty-two (51%) patients remain in complete remission 6-81 months (median 24 months) after ABMT.

The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants.  相似文献   
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Fifteen patients with very poor prognosis Hodgkin's disease in remission after MOPP/ABVD regimen, were treated with high-dose chemotherapy (HDC) and autologous marrow transplantation (ABMT) immediately after achieving complete remission (CR). Thirteen patients (86.6%) remain alive in unmaintained CR at a median time of 36 months (range 10-64 months) post-transplant. In the other two patients reasons for failure included relapse of Hodgkin's disease (one patient) and death due to interstitial pneumonitis secondary to carmustine therapy. These patients were compared with a historical control group consisting of 24 patients with the same poor prognostic factors, who achieved CR with MOPP/ABVD and did not receive other treatment. Eight out of 24 patients (33%) remain alive and well in unmaintained CR at a median time of 42 months (range 19-83 months). The administration of MOPP/ABVD combined with HDC and ABMT was not associated with an increased incidence of major toxicity. The results achieved support the early sequential treatment of a highly effective drug combination followed by HDC/ABMT that can substantially improve the likelihood of cure in these advanced stage very poor prognosis Hodgkin's disease patients.  相似文献   
8.
Biochemical mechanisms which control cardiac and vascular response to hypertension are still unclear. Modifications of polyamines (putrescine, spermine, spermidine) may play a role in this phenomenon, since these molecules have been shown of importance in the control of tissue growth. Ornithine Decarboxylase (ODC) catalyses the first and probably the rate limiting step in the biosynthesis of the polyamines. We thus attempted to detect modification of ODC activity in renovascular hypertension in the rat (G1K-1C) and tried to correlate hypertrophic response and ODC activity in the aorta (Ao), the left (LV) and the right (RV) ventricles. In this experimental model, the aortic ODC activity increased at day 1 and 2, after clipping the renal artery, whereas in the LV the ODC activity increased after day 3 but stay high at least until day 7. The peak of ODC activity comes before the increase in DNA synthesis which occurs at day 4 in Ao, and the increase in protein turnover observed at day 7 in LV. No significant variation of ODC activity neither changes in DNA or protein biosynthesis rate are observed in the RV. In parallel with changes in ODC activity, an increase in spermidine and spermine content and mainly in the spermidine/spermine ratio is observed in the Ao and the LV confirming stimulation in polyamine biosynthesis in hypertensive tissues. In conclusion: increase in ODC activity is observed only in these tissues that will develop hypertrophy or hyperplasia and this modification is observed before any increase in nucleic acids or protein tissues content or turnover rate.  相似文献   
9.
The usual agent of visceral leishmaniasis in the Old World is Leishmania donovani, which typically produces systemic diseases in humans and mice. L. donovani has developed efficient strategies to infect and persist in macrophages from spleen and liver. Dendritic cells (DC) are sentinels of the immune system. Following recognition of evolutionary conserved microbial products, DC undergo a maturation process and activate antigen-specific na?ve T cells. In the present report we provide new insights into how DC detect Leishmania in vivo. We demonstrate that in both C57BL/6 and BALB/c mice, systemic injection of L. donovani induced the migration of splenic DC from marginal zones to T-cell areas. During migration, DC upregulated the expression of major histocompatibility complex II and costimulatory receptors (such as CD40, CD80, and CD86). Leishmania-induced maturation requires live parasites and is not restricted to L. donovani, as L. braziliensis, L. major, and L. mexicana induced a similar process. Using a green fluorescent protein-expressing parasite, we demonstrate that DC undergoing maturation in vivo display no parasite internalization. We also show that L. donovani-induced DC maturation was partially abolished in MyD88-deficient mice. Taken together, our data suggest that Leishmania-induced DC maturation results from direct recognition of Leishmania by DC, and not from DC infection, and that MyD88-dependent receptors are implicated in this process.  相似文献   
10.
Hepatitis A virus (HAV) is a worldwide disease; in most cases, it causes an acute self-limited illness that does not lead to a chronic state. The course of HAV viremia in a homosexual male with human immunodeficiency virus type 1 (HIV-1) and the correlation between HIV and HAV viral load, alanine aminotranferase (ALT) level, and CD4(+) lymphocyte count were investigated during the course of the infection. HAV RNA was detected quantitatively up to 256 days after clinical onset. To our knowledge, this specific case is the first report of a prolonged infection with hepatitis A in a male with HIV-1. The ALT levels decreased gradually; however, 286 days after clinical onset of hepatitis, ALT levels were three times higher than normal values. HIV viral load was not affected by the infection with HAV and CD4(+) cell count was stable during the course of the co-infection. The duration and the high-titer viremia of hepatitis A virus in an immunodeficient patient constitute a serious risk of the spread of hepatitis A within this population. As inactivated HAV vaccine is safe in HIV-positive subjects, it would be wise to establish a strategy of preventive vaccination in this high-risk group.  相似文献   
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