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171.
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Behavioral and psychological symptoms of dementia (BPSD) have not been comprehensively studied in people with Down syndrome, despite their high risk on dementia. A novel evaluation scale was developed to identify the nature, frequency and severity of behavioral changes (83 behavioral items in 12 clinically defined sections). Central aim was to identify items that change in relation to the dementia status. Structured interviews were conducted with informants of people with Down syndrome without dementia (DS, N?=?149), with questionable dementia (DS?+?TD, N?=?65) and with diagnosed dementia (DS?+?AD, N?=?67). Group comparisons showed a pronounced increase in frequency and severity of items about anxiety, sleep disturbances, agitation & stereotypical behavior, aggression, apathy, depressive symptoms, and, eating/drinking behavior. The proportion of individuals presenting an increase was highest in the DS?+?AD group and lowest in the DS group. Interestingly, among DS?+?TD individuals, a substantial proportion already presented increased anxiety, sleep disturbances, apathy and depressive symptoms, suggesting that these changes may be early alarm signals of dementia. The scale may contribute to a better understanding of the changes, adapting daily care/support, and providing suitable therapies to people with Down syndrome. The scale needs to be optimized based on the results and experiences. The applicability, reliability and validity require further study.  相似文献   
173.
IgG antibodies can organize into ordered hexamers on cell surfaces after binding their antigen. These hexamers bind the first component of complement C1 inducing complement-dependent target cell killing. Here, we translated this natural concept into a novel technology platform (HexaBody technology) for therapeutic antibody potentiation. We identified mutations that enhanced hexamer formation and complement activation by IgG1 antibodies against a range of targets on cells from hematological and solid tumor indications. IgG1 backbones with preferred mutations E345K or E430G conveyed a strong ability to induce conditional complement-dependent cytotoxicity (CDC) of cell lines and chronic lymphocytic leukemia (CLL) patient tumor cells, while retaining regular pharmacokinetics and biopharmaceutical developability. Both mutations potently enhanced CDC- and antibody-dependent cellular cytotoxicity (ADCC) of a type II CD20 antibody that was ineffective in complement activation, while retaining its ability to induce apoptosis. The identified IgG1 Fc backbones provide a novel platform for the generation of therapeutics with enhanced effector functions that only become activated upon binding to target cell–expressed antigen.  相似文献   
174.

Background

A major challenge in the control of human African trypanosomiasis (HAT) is lack of reliable diagnostic tests that are rapid and easy to use in remote areas where the disease occurs. In Trypanosoma brucei gambiense HAT, the Card Agglutination Test for Trypanosomiasis (CATT) has been the reference screening test since 1978, usually on whole blood, but also in a 1/8 dilution (CATT 1/8) to enhance specificity. However, the CATT is not available in a single format, requires a cold chain for storage, and uses equipment that requires electricity. A solution to these challenges has been provided by rapid diagnostic tests (RDT), which have recently become available. A prototype immunochromatographic test, the SD BIOLINE HAT, based on two native trypanosomal antigens (VSG LiTat 1.3 and VSG LiTat 1.5) has been developed. We carried out a non-inferiority study comparing this prototype to the CATT 1/8 in field settings.

Methodology/Principal Findings

The prototype SD BIOLINE HAT, the CATT Whole Blood and CATT 1/8 were systematically applied on fresh blood samples obtained from 14,818 subjects, who were prospectively enrolled through active and passive screening in clinical studies in three endemic countries of central Africa: Angola, the Democratic Republic of the Congo and the Central African Republic. One hundred and forty nine HAT cases were confirmed by parasitology. The sensitivity and specificity of the prototype SD BIOLINE HAT was 89.26% (95% confidence interval (CI) = 83.27–93.28) and 94.58% (95% CI = 94.20–94.94) respectively. The sensitivity and specificity of the CATT on whole blood were 93.96% (95% CI = 88.92–96.79) and 95.91% (95% CI = 95.58–96.22), and of the CATT 1/8 were 89.26% (95% CI = 83.27–93.28) and 98.88% (95% CI = 98.70–99.04) respectively.

Conclusion/Significance

After further optimization, the prototype SD BIOLINE HAT could become an alternative to current screening methods in primary healthcare settings in remote, resource-limited regions where HAT typically occurs.  相似文献   
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The African cichlid Oreochromis mossambicus (Mozambique tilapia) has been used as a model system in a wide range of behavioural and neurobiological studies. The increasing number of genetic tools available for this species, together with the emerging interest in its use for neurobiological studies, increased the need for an accurate hodological mapping of the tilapia brain to supplement the available histological data. The goal of our study was to elaborate a three-dimensional, high-resolution digital atlas using magnetic resonance imaging, supported by Nissl staining. Resulting images were viewed and analysed in all orientations (transverse, sagittal, and horizontal) and manually labelled to reveal structures in the olfactory bulb, telencephalon, diencephalon, optic tectum, and cerebellum. This high resolution tilapia brain atlas is expected to become a very useful tool for neuroscientists using this fish model and will certainly expand their use in future studies regarding the central nervous system.  相似文献   
177.
‘Big-data’ epidemic models are being increasingly used to influence government policy to help with control and eradication of infectious diseases. In the case of livestock, detailed movement records have been used to parametrize realistic transmission models. While livestock movement data are readily available in the UK and other countries in the EU, in many countries around the world, such detailed data are not available. By using a comprehensive database of the UK cattle trade network, we implement various sampling strategies to determine the quantity of network data required to give accurate epidemiological predictions. It is found that by targeting nodes with the highest number of movements, accurate predictions on the size and spatial spread of epidemics can be made. This work has implications for countries such as the USA, where access to data is limited, and developing countries that may lack the resources to collect a full dataset on livestock movements.  相似文献   
178.
This study was designed to examine the cellular distribution of the angiotensin II type-1 (AT1) and type-2 (AT2) receptors in the normal human and pathological human lung. Riboprobes were prepared against specific portions of each receptor DNA and labelled with FITC for detection using an anti-FITC antibody in combination with the alkaline phosphatase-anti-alkaline phosphatase technique and new Fuchsin. These were used to detect the presence of receptor mRNA in the lung. Specific antibodies were used to detect receptor protein in cells by immunocytochemistry. Image analysis was used in order to semi-quantify receptor density. AT1 receptor mRNA and protein were localised on vascular smooth muscle cells, macrophages and in the stroma underlying the airways epithelium probably relating to underlying fibroblasts. The AT1 receptor protein was not expressed in the epithelium although there was a low level of mRNA. In contrast, AT2 receptor RNA and protein was observed in the epithelium, with strong staining on the bronchial epithelial cell brush border and also on many of the underlying mucous glands. The AT2 receptor was also present on some endothelial cells. These findings were supported by the presence of mRNA in each case. In patients with chronic obstructive pulmonary disease, there was a five- to sixfold increase in the ratio of AT1 to AT2 receptors in the regions of marked fibrosis surrounding the bronchioles. This correlated well with the reduced lung function as expressed by the forced expiratory volume.  相似文献   
179.
In Democratic Republic of Congo access to health care is limited because of many geographical and financial barriers, while quality of care is often low. Global health donors assist the country with a number of community-oriented interventions such as free distribution of bednets, antihelminthic drugs, vitamin A supplementation and vaccination campaigns, but uptake of these interventions is not always optimal. The aim of this study was to explore the perceptions of poor urban communities of the capital Kinshasa with regard to health issues in general as well as their experiences and expectations concerning facility-based health services and community-oriented health interventions. Applying an approach rooted in the grounded theory framework, focus group discussions were conducted in eight neighborhoods of poor urban areas in the city of Kinshasa in July 2011. Study participants were easily able to evoke the city’s major health problems, with the notable exceptions of malnutrition and HIV/AIDS. They perceive the high out-of-pocket cost of health services as the major obstacle when seeking access to quality care. Knowledge of ongoing community-oriented health interventions seems good. Still, while the study participants agree that those interventions are beneficial; their acceptability seems to be problematic. This is chiefly put down to a lack of information and government communication about the programs and their interventions. Furthermore, the study participants referred to rumors and the deterring effect of stories about alleged harmful consequences of those interventions. Along with improving the provision and quality of general health care, the government and international actors must improve their efforts in informing the communities about disease control programs, their rationale and benefit/risk ratio. Directly engaging community members in a dialogue might be beneficial in terms of improving acceptability and overall access to health services and interventions. Novel ways of reducing the high out-of-pocket expenditure should also be explored.  相似文献   
180.
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