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991.

OBJECTIVE

To assess the impact of hyperglycemia in different age-groups of patients with acute myocardial infarction (AMI).

RESEARCH DESIGN AND METHODS

A total of 2,027 patients with AMI were categorized into one of five age-groups: <50 years (n = 301), ≥50 and <60 (n = 477), ≥60 and <70 (n = 545), ≥70 and <80 (n = 495), and ≥80 years (n = 209). Hyperglycemia was defined as initial glucose ≥115 mg/dL.

RESULTS

The adjusted odds ratios for hyperglycemia predicting hospital mortality in groups 1–5 were, respectively, 7.57 (P = 0.004), 3.21 (P = 0.046), 3.50 (P = 0.003), 3.20 (P < 0.001), and 2.16 (P = 0.021). The adjusted P values for correlation between glucose level (as a continuous variable) and mortality were 0.007, <0.001, 0.043, <0.001, and 0.064. The areas under the ROC curves (AUCs) were 0.785, 0.709, 0.657, 0.648, and 0.613. The AUC in group 1 was significantly higher than those in groups 3–5.

CONCLUSIONS

The impact of hyperglycemia as a risk factor for hospital mortality in AMI is more pronounced in younger patients.Elevated glucose level (GL) is an independent risk factor for mortality in patients with acute myocardial infarction (AMI) (13), in part related to its adverse effects on microcirculation and left ventricular remodeling (4). Particularly in older people, hyperglycemia is a common complication that increases the risk of death (5). However, less is known about the impact of hyperglycemia in younger patients with AMI. Furthermore, the comparison of the impact of GL in different age-groups, particularly in very elderly adults (>80 years) versus younger adults (<50 years), has not been well studied and is the primary focus of this study.  相似文献   
992.

OBJECTIVES:

The current study sought to identify macroscopic placental changes associated with clinical conditions in women with or without diabetes and their newborns.

METHODS:

The study population consisted of 62 pregnant women clinically diagnosed with diabetes and 62 healthy women (control group).

RESULTS:

Among the subjects with diabetes, 43 women (69.3%) were diagnosed with gestational diabetes mellitus, 15 had diabetes mellitus I (24.2%), and four had diabetes mellitus II (6.5%). The mean age of the women studied was 28.5±5.71 years, and the mean gestational age of the diabetic women was 38.51 weeks. Of the 62 placentas from diabetic pregnancies, 49 (79%) maternal surfaces and 59 (95.2%) fetal surfaces showed abnormalities, including calcium and fibrin deposits, placental infarction, hematoma, and fibrosis. A statistical association was found between newborn gender and fetal and maternal placental changes (p = 0.002). The mean weight of the newborns studied was 3,287±563 g for women with diabetes mellitus, 3,205±544 g for those with gestational diabetes mellitus, 3,563±696 g for those with diabetes mellitus II, and 3,095±451 g for those with diabetes mellitus I.

CONCLUSIONS:

Infarction, hematoma, calcification, and fibrin were found on the maternal and fetal placental surfaces in women with diabetes. Women with gestational diabetes and post-term infants had more calcium deposits on the maternal placental surface as compared to those with type I and type II diabetes.  相似文献   
993.

OBJECTIVE:

Bardet-Biedl syndrome is a genetic, multisystem disorder that causes severe visual impairment. This condition is characterized by retinal dystrophy, obesity, digit anomalies, renal disease, and hypogonadism. The purpose of this study was to analyze visual acuity and full-field electroretinogram findings in patients with the Bardet-Biedl syndrome phenotype.

METHODS:

The visual acuity of a group of 23 patients (15 males) with ages ranging from 6-36 years (mean = 15.8±6.4; median = 14.7) was assessed. Retinal function was evaluated by full-field electroretinography, and dark-adapted thresholds were assessed.

RESULTS:

Visual acuity in the better-seeing eye was 20/40 or better in 5 patients (21.7%), 20/50-20/150 in 13 (56.5%) patients, 20/200-20/400 in 2 (8.7%) patients and worse than 20/400 in one (4.3%) patient. The mean acuity in the better-seeing eye was 0.7±0.6 logMAR (20/100, Snellen equivalent). Scotopic rod and maximal responses were non-detectable in 21 (91.3%) patients, and cone responses were non-detectable in 15 (65.2%) patients. Elevated dark-adapted visual thresholds were observed in all 19 patients who were able to be assessed, with 10 (52.6%) patients having thresholds greater than 30 dB.

CONCLUSIONS:

In a relatively young cohort of patients with Bardet-Biedl syndrome, only 21% had 20/40 or better vision. ERG scotopic responses were absent in the majority of cases, with cone responses being observed in less than half of cases. These findings showed the early deleterious effects in retinal function and visual acuity caused by this condition.  相似文献   
994.
995.
The GABA-ergic system, known to regulate neural tissue genesis during cortical development, has been postulated to play a role in cerebral aging processes. Using in vivo molecular imaging and voxel-wise quantification, we aimed to assess the effects of aging on the benzodiazepine (BDZ) recognition site of the GABA(A) receptor. To visualize BDZ site availability, [(11)C]-flumazenil microPET acquisitions were conducted in young and old rats. The data were analyzed and region of interest analyses were applied to validate the voxel-wise approach. We observed decreased [(11)C]-flumazenil binding in the aged rat brains in comparison with the young control group. More specifically, clusters of reduced radioligand uptake were detected in the bilateral hippocampus, cerebellum, midbrain, and bilateral frontal and parieto-occipital cortex. Our results support the pertinence of voxel-wise quantification in the analysis of microPET data. Moreover, these findings indicate that the aging process involves declines in neural BDZ recognition site availability, proposed to reflect alterations in GABA(A) receptor subunit polypeptide expression.  相似文献   
996.
In this study, the authors evaluated the ability of diphenyl diselenide (PhSe)(2) to reverse acute hepatic failure induced by acetaminophen (APAP) in mice. The animals received an APAP dose of 600 mg/kg intraperitoneally (i.p.), and then 1 hour later, they received 15.6 mg/kg i.p. of (PhSe)(2). Three hours after (PhSe)(2) administration, the animals were sacrificed and blood and liver samples were collected for analysis. The serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured. The levels of reduced glutathione (GSH) and oxidized glutathione (GSSG), thiobarbituric acid-reactive substances (TBARS), 2',7'-dichlorofluorescein (DFC), catalase activity (CAT), and myeloperoxidase (MPO) activity were determined in the liver. A methyl-tetrazolium reduction (MTT) assay was also performed on the liver. Histopathological studies were conducted in all groups. Exposure of animals to APAP induced oxidative stress, increased lipid peroxidation (LPO), and the generation of reactive species, reduced the levels of GSH, and caused an increase in the MPO activity. Treatment with (PhSe)(2) reduced LPO and the formation of reactive species and inhibited the processes of inflammation, reducing the hepatic damage induced by APAP. The results of this study show that (PhSe)(2) is a promising therapeutic option for the treatment of acute hepatic failure.  相似文献   
997.
Medium and short-chain 3-hydroxyacyl-CoA dehydrogenase deficiency is a rare cause of impaired mitochondrial fatty acid oxidation. We present a case report of a patient with hyperinsulinism and homozygosity for a novel mutation causing a kinetic variant of the enzyme. The diagnosis was initially inferred by abnormal newborn screening acylcarnitine analysis with elevated C4-hydroxyacylcarnitine.  相似文献   
998.
Introduction: Various cytokines have been associated to the occurrence of bronchopulmonary dysplasia (BPD) in preterm neonates. AIM: To establish an association between cord blood cytokines and BPD, so that they could be used, in clinical practice, as early markers of BPD. Material and methods: Preterms less than 30 weeks gestational age, were analysed by ELISA microassay for venous cord blood IL-1β, IL-6, IL-8, TNF-α and IL-10, and compared between the BPD and non-BPD groups. Results: One hundred and fifty neonates completed the study; 31 (21%) small for gestational age (SGA); 16 were deceased before 28 days of life; 36 developed mild BPD and 20 developed moderate/severe BPD. Elevated cord blood IL-8 was associated with death or moderate/severe BPD. SGA patients with moderate/severe BPD presented higher cord blood values of IL-8, lower IL-6 and IL-10 when compared with SGA without moderate/severe BPD; and higher IL-8 levels when compared with patients without moderate/severe BPD. Conclusion: These results support an association between cord blood IL-8 and moderate/severe BPD, independently of the intra-uterine growth; and the association of cord blood IL-6 and IL-10 and moderate/severe BPD in SGA preterm newborns.  相似文献   
999.
Although the pathophysiology of Chagas disease is not completely understood, it is widely accepted that involvement of the immune response is critical in determining the outcome of the disease. In this context, CD4+ T cells may play an important role in generating different mechanisms of protection. In addition to effector and regulatory functions, CD4+ T cells may be also involved with lytic activities against the parasite and may have a relevant role on control of the infection. In this study, we have evaluated CD4+ T cells expressing cytotoxic and apoptosis markers in response to Trypanossoma cruzi infection in indeterminate (IND) and cardiac (CARD) patients with Chagas disease and non‐infected individuals (NI). Our data demonstrated that: (1) CD4+ T cells presented higher ex vivo granzyme B expression in patients with Chagas disease compared with healthy individuals and that antigen induced a greater granzyme B expression in IND patients; (2) CD95L expression in CD4+ CD95+ T cells from IND patients is higher than in CARD and NI; (3) IND and CARD patients had an increased frequency of caspase‐3 after in vitro stimulation and also expressed a high frequency of annexinV+ 7ADD+ within CD4+ T cells; (4) Lastly, a positive correlation was seen between cytotoxic molecules and CD45RO memory marker in CD4+ T cells and between caspase‐3 and CD95L within CD4+ CD95+ T cells. These results suggest new insights into the functional competence of CD4+ T cells among the different clinical forms of Chagas disease, which will lead to a better understanding of their influence during immune responses against T. cruzi.  相似文献   
1000.
Imidazolidine derivatives are key components for the development of bioactive compounds for the treatment of many diseases, especially Chagas. In fact, others studies showed that the imidazolidine-2,4-dione has stood out by presenting a wide spectrum of pharmacological activities including anticonvulsants, antiarrhythmic, and antiparasitic. In the present study, we investigated the morphological alterations induced by imidazolidine derivates LPSF/NN-52 and LPSF/NN-100 on trypomastigotes forms of Trypanosoma cruzi through ultrastructural analysis by electron microscopy. Many concentrations were used to measure the antiparasitic propriety promoted by imidazolidine derivatives, and our study indicates that parasites treated with 13???g?mL?1 of the imidazolidine derivates for 24?h revealed severe damage to the parasite??s mitochondrial complex. Beyond that, also observed in treated parasites were the following: myelin bodies, enlargement of cytoplasm vacuole, fragmentation of endoplasmic reticulum, and some treated samples clearly showed signs of necrosis. To confirm the ultrastructural results, some assays were performed for knowledge cellular death induction promoted by imidazolidine derivates against immune spleen cells. The induction of the necrotic process through derivatives LPSF/NN-52 and LPSF/NN-100 showed similar results in relation to nifurtimox and benznidazole. In the last assays, it was demonstrated that NN-100 was efficient against epimastigotes and trypomastigotes forms and these results reinforce the mechanisms of action of both new imidazolidine derivatives against T. cruzi.  相似文献   
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