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991.
992.
Left ventricular hypertrophy (LVH) is associated with worse outcomes in chronic obstructive pulmonary disease (COPD); however, its role in an acute exacerbation of COPD (AECOPD) has not been reported. This was a retrospective cohort study during 2008–2012 at an academic medical center. AECOPD patients >18 years with available echocardiographic data were included. LVH was defined as LV mass index (LVMI) >95 g/m2 (women) and >115g/m2 (men). Relative wall thickness was used to classify LVH as concentric (>0.42) or eccentric (<0.42). Outcomes included need for and duration of non-invasive ventilation (NIV) and mechanical ventilation (MV), NIV failure, intensive care unit (ICU) and total length of stay (LOS), and in-hospital mortality. Two-tailed p < 0.05 was considered statistically significant. Of 802 patients with AECOPD, 615 patients with 264 (42.9%) having LVH were included. The LVH cohort had higher LVMI (141.1 ± 39.4 g/m2 vs. 79.7 ± 19.1 g/m2; p < 0.001) and lower LV ejection fraction (44.5±21.9% vs. 50.0±21.6%; p ≤ 0.001). The LVH cohort had statistically non-significant longer ICU LOS, and higher NIV and MV use and duration. Of the 264 LVH patients, concentric LVH (198; 75.0%) was predictive of greater NIV use [82 (41.4%) vs. 16 (24.2%), p = 0.01] and duration (1.0 ± 1.9 vs. 0.6 ± 1.4 days, p = 0.01) compared to eccentric LVH. Concentric LVH remained independently associated with NIV use and duration. In-hospital outcomes in patients with AECOPD were comparable in patients with and without LVH. Patients with concentric LVH had higher NIV need and duration in comparison to eccentric LVH.  相似文献   
993.
A major challenge to the success of malaria control program in Saudi Arabia is the high influx of expatriates and holy visitors from malaria endemic countries. In the present study we examined whether drug resistant parasite genotypes reported in Jazan region, southwest of Saudi Arabia are imported or developed locally. We examined 178 Plasmodium falciparum isolates for alleles of dihydropteroate synthase (dhps) and dihydrofolate reductase (dhfr), associated with Sulfadoxine-Pyrimethamine (SP) resistance, and three microsatellites flanking each gene. In addition, we examined a neutral polymorphic gene (Pfg377). We compared the dhfr and dhps haplotypes in Jazan, using network analysis, to an existing similar data set of 94 P. falciparum isolates from eastern Sudan. In Jazan, double mutant dhfr allele (51I, 108N) occurred with a prevalence of 33%. The vast majority (99%) of dhps were wild-type alleles. The mean expected heterozygosity (He) of microsatellites around mutant dhfr alleles (He = 0.312; n = 60) was lower (P ? 0.05) than that around the wild-type allele (He = 0.834; n = 116). Also, the mutant dhfr isolates showed high He for dhps (He = 0.80) and the non-drug resistance locus Pfg377 (He = 0.63) indicative of selection for mutant dhfr only. The predominant double mutant dhfr haplotype in Jazan (73%), was prevalent among P. falciparum in east Africa. Network analysis suggests the mutant haplotype of dhfr gene was possibly introduced into Jazan from East Africa. The absence of mutations in dhps as well as triple mutant dhfr haplotype associated with SP failure support the current use of SP as a partner with artesunate as a first line therapy in Saudi Arabia. However, the close relationship between the major mutant dhfr haplotype in Sudan and Saudi Arabia, favour the hypothesis of recent migration as a source of the major resistant dhfr lineage. Thus, regular monitoring of the dhfr and dhps haplotypes is of high priority to guard possible importation of high level SP resistant lineages.  相似文献   
994.
BackgroundThe COVID-19 pandemic has had enormous impacts on people’s lives, including disruptions to their normal ways of behaving, working, and interacting with others. Understanding and documenting these experiences is important to inform the ongoing response to COVID-19 and disaster preparedness efforts.ObjectiveThe aim of this study was to examine the psychosocial impacts of COVID-19 on a sample of Australian adults.MethodsThe data analyzed were derived from a larger cross-sectional survey of Australian adults that was administered during the month of May 2020. Participants (N=3483) were asked in which ways COVID-19 had most greatly impacted them; the responses produced a text data set containing 1 COVID-19 impact story for each participant, totaling 86,642 words. Participants also completed assessments of their sociodemographic characteristics (sex, age, financial stress), level of concern related to COVID-19, personality trait profile, and satisfaction with life. Impact stories were analyzed using sentiment analysis and compared against the Theoretical Domains Framework to determine the most frequently impacted life domains. Finally, a multinomial regression analysis, stratified by participant sex, was conducted to identify the associations of psychological and demographic socializations with sentiment toward COVID-19.ResultsIn total, 3483 participants completed the survey, the majority of whom were female (n=2793, 80.2%). Participants’ impact stories were most commonly categorized as neutral (1544/3483, 44.3%), followed by negative (1136/3483, 32.6%) and positive (802/3483, 23.1%). The most frequently impacted life domains included behavioral regulation, environmental context and resources, social influences, and emotions, suggesting that the COVID-19 pandemic was impacting these areas of participants’ lives the most. Finally, the regression results suggested that for women, lower satisfaction with life and higher financial stress were associated with increased likelihood of negative, rather than positive, sentiment (P<.001); however, the proportion of variance in the sentiment that was explained was very small (<5%).ConclusionsParticipant sentiment toward COVID-19 varied. High rates of neutral and negative sentiment were identified. Positive sentiment was identified but was not as common. Impacts to different areas of people’s lives were identified, with a major emphasis on behavioral regulation and related domains such as social influences, environmental context and resources, and emotions. Findings may inform the development of mental health and social support resources and interventions to help alleviate the psychosocial consequences of disaster response measures.  相似文献   
995.
Background/aim Sleep deprivation disrupts prepulse inhibition of acoustic startle reflex and can be used to mimic psychosis in experimental animals. On the other hand, it is also a model for other disorders of sensory processing, including migraine. This study aims to assess the effects of sodium valproate, a drug that is used in a variety of neuropsychiatric disorders, on normal and disrupted sensorimotor gating in rats.Materials and methods Sixty-two Wistar albino rats were randomly distributed into 8 groups. Subchronic and intraperitoneal sodium valproate were administrated to the sleep-deprived and nonsleep-deprived rats by either 50–100 or 200 mg/kg/day. Prepulse inhibition test and locomotor activity test were performed. Sleep deprivation induced by the modified multiple platform method.Results Sleep deprivation impaired prepulse inhibition, decreased startle amplitude, and increased locomotor activity. Sodium valproate did not significantly alter prepulse inhibition and locomotor activity in nonsleep-deprived and sleep-deprived groups. On the other hand, all doses decreased locomotor activity in drug-treated groups, and low dose improved sensorimotor gating and startle amplitude after sleep deprivation.Conclusion Low-dose sodium valproate improves sleep deprivation-disrupted sensorimotor gating, and this finding may rationalize the use of sodium valproate in psychotic states and other sensory processing disorders. Dose-dependent effects of sodium valproate on sensorimotor gating should be investigated in detail.  相似文献   
996.

Objective

To describe the spectrum of congenital heart disease in children with Down syndrome and their cytogenetic profile (and that of parents of those with translocation), and thyroid profile.

Methods

A cross sectional study was conducted in 418 consecutive patients with Down syndrome attending the Department of Pediatric Genetics from a tertiary care centre in Kerala with a comprehensive Pediatric Cardiac Program, from November 2005 through April 2012. All children were offered cytogenetic analysis and were subjected to echocardiography. Parental karyotyping was offered for children with translocation type of Down syndrome. The thyroid profiles of all children were checked at the first visit and once every 6 mo during follow up.

Results

Congenital heart disease was present in 256 (63.4 %) of 404 children with Down syndrome. Ventricular septal defect (72; 28.1 %) was the commonest, followed by atrio-ventricular septal defect (70; 27.3 %) and patent ductus arteriosus (43; 16.8 %). Surgical correction was accomplished in 104 (40.6 %) with excellent intermediate-term outcomes. Three hundred eighty seven of 418 children (92.6 %) underwent cytogenetic tests. The abnormalities included non-disjunction (340, 87.8 %), translocation (33, 8.5 %) and mosaicism (12, 3.1 %). Hypothyroidism was detected in 57 children (13.6 %).

Conclusions

The prevalence of congenital heart disease in children with Down syndrome in Kerala is the highest reported (63.4 %). Ventricular septal defect is the most common heart disease in the present study. The results highlight the changing attitudes of families towards the surgical correction of congenital heart disease in children with Down syndrome. Prevalence of hypothyroidism in Down syndrome in Kerala is 13.6 %.  相似文献   
997.

Background

Malaria and human immunodeficiency virus (HIV) are two major infections with enormous public health consequence. Together, they are endemic in many developing countries with anaemia being the most frequent haematological consequence of the infections.

Objectives

To determine the prevalence of malaria and HIV co-infection as well as anaemia among selected patients from three health-care institutions in Lagos, Nigeria.

Methods

A cross-sectional study of 1080 patients was carried out to determine the prevalence of malaria and HIV co-infection as well as anaemia. Blood sera from each of the patients were screened for malaria parasites, HIV-1 and HIV-2 using Giemsa stain, Cambridge Biotech Recombigen HIV-1/HIV-2 rapid device, respectively while haemoglobin estimation was performed using cyanmethemoglobin method.

Results

Our data showed that the total number of malaria infected patients were significantly higher in HIV sero-positive patients 47.7% (31/65) when compared with their HIV sero-negative counterparts 25.8% (262/1015) P = 0.047. The result also revealed that 25.8% (8/31) of the patients co-infected with malaria and HIV had anaemia as compared to 11.1% (29/262) infected with malaria alone. Multivariable logistic regression analysis showed that patients with dual infection of malaria and HIV were twice likely to be anaemic than those infected with malaria alone [adjusted OR 2.4, 95% CI, 1.3 to 2.7, P = 0.014].

Conclusions

Our data indicated a higher prevalence of malaria in HIV infected patients and also revealed that patients co-infected with malaria and HIV were more likely to be anaemic.  相似文献   
998.
999.

Background

Detection of cardiac fibrosis based on endogenous magnetic resonance (MR) characteristics of the myocardium would yield a measurement that can provide quantitative information, is independent of contrast agent concentration, renal function and timing. In ex vivo myocardial infarction (MI) tissue, it has been shown that a significantly higher T is found in the MI region, and studies in animal models of chronic MI showed the first in vivo evidence for the ability to detect myocardial fibrosis with native T-mapping. In this study we aimed to translate and validate T-mapping for endogenous detection of chronic MI in patients.

Methods

We first performed a study in a porcine animal model of chronic MI to validate the implementation of T-mapping on a clinical cardiovascular MR scanner and studied the correlation with histology. Subsequently a clinical protocol was developed, to assess the feasibility of scar tissue detection with native T-mapping in patients (n = 21) with chronic MI, and correlated with gold standard late gadolinium enhancement (LGE) CMR. Four T-weighted images were acquired using a spin-lock preparation pulse with varying duration (0, 13, 27, 45 ms) and an amplitude of 750 Hz, and a T-map was calculated. The resulting T-maps and LGE images were scored qualitatively for the presence and extent of myocardial scarring using the 17-segment AHA model.

Results

In the animal model (n = 9) a significantly higher T relaxation time was found in the infarct region (61 ± 11 ms), compared to healthy remote myocardium (36 ± 4 ms) . In patients a higher T relaxation time (79 ± 11 ms) was found in the infarct region than in remote myocardium (54 ± 6 ms). Overlap in the scoring of scar tissue on LGE images and T-maps was 74%.

Conclusion

We have shown the feasibility of native T-mapping for detection of infarct area in patients with a chronic myocardial infarction. In the near future, improvements on the T -mapping sequence could provide a higher sensitivity and specificity. This endogenous method could be an alternative for LGE imaging, and provide additional quantitative information on myocardial tissue characteristics.  相似文献   
1000.
Celiac disease (CD) has a wide variety of clinical presentations; together with the "classical form", in which the intestinal symptomatology is prevalent, there are "atypical forms" with predominating extra-intestinal clinical features, and the "silent form", with no clinical symptom. The "atypical forms" of the disease are characterized by few or no gastrointestinal symptoms, and predominating extra-intestinal features such as neurologic, dermatologic, hematologic, endocrinologic, reproductive, renal, psychiatric, skeletal, and liver involvement(s). Silent presentation of CD may be identified through screening of high-risk groups. Today, it is well known that CD might account for several chronic health issues, so it is essential for healthcare professionals to have a high level of suspicion for the atypical presentations of CD.  相似文献   
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