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91.
92.

Background

Despite policies that recommend parasitological testing before treatment for malaria, presumptive treatment remains widespread in Nigeria. The majority of Nigerians obtain antimalarial drugs from two types of for-profit drug vendors—formal and informal medicine shops—but little is known about the quality of malaria care services provided at these shops.

Aims

This study seeks to (1) describe the profile of patients who seek treatment at different types of drug outlets, (2) document the types of drugs purchased for treating malaria, (3) assess which patients are purchasing recommended drugs, and (4) estimate the extent of malaria over-treatment.

Methods

In urban, peri-urban, and rural areas in Oyo State, customers exiting proprietary and patent medicine vendor (PPMV) shops or pharmacies having purchased anti-malarial drugs were surveyed and tested with malaria rapid diagnostic test. A follow-up phone survey was conducted four days after to assess self-reported drug administration. Bivariate and multivariate regression analysis was conducted to determine the correlates of patronizing a PPMV versus pharmacy, and the likelihood of purchasing an artemisinin-combination therapy (ACT) drug.

Results

Of the 457participants who sought malaria treatment in 49 enrolled outlets, nearly 92% had diagnosed their condition by themselves, a family member, or a friend. Nearly 60% pharmacy customers purchased an ACT compared to only 29% of PPMV customers, and pharmacy customers paid significantly more on average. Multivariate regression results show that patrons of PPMVs were younger, less wealthy, waited fewer days before seeking care, and were less likely to be diagnosed at a hospital, clinic, or laboratory. Only 3.9% of participants tested positive with a malaria rapid diagnostic test.

Conclusions

Poorer individuals seeking care at PPMVs are more likely to receive inappropriate malaria treatment when compared to those who go to pharmacies. Increasing accessibility to reliable diagnosis should be explored to reduce malaria over-treatment.  相似文献   
93.
Cytological analysis of body fluids is currently used for detecting cancer. The objective of this study was to determine if the herpes virus carrying an enhanced green fluorescent protein (EGFP) could detect rare cancer cells in body fluids against millions of normal cells. Human cancer cells suspended with normal murine cells were infected with NV1066 at a multiplicity of infection (MOI) of 0.5 and 1.0 for 18 h. Fluorescent microscopy and flow cytometry were used for EGFP detection of cancer cells. EGFP-expressing cells were confirmed as cancer cells with specific markers by immunohistochemistry staining. Limits of detection of cancer cells in body fluid were measured by serial dilutions. Applicability of technique was confirmed with samples from patients with malignant pleural effusions. NV1066 expressed EGFP in 111 human cancer cell lines detected by fluorescent microscopy at an MOI of 0.5. NV1066 selectively infected cancer cells and spared normal cells as confirmed by immunohistochemistry. Sensitivity of detecting fluorescent green cells was 92% (confidence interval [CI] 83% to 97%) at a ratio of 1 cancer cell to 1 million normal cells. EGFP-positive cells were detected by fluorescent microscopy in patients' malignant pleural effusion samples. Our data show proof of the concept that NV1066-induced EGFP expression allows detection of a single cancer cell against a background of 1 million normal cells. This method was demonstrated to be a reliable screening tool for human cancer cells in a suspension of normal murine cells as well as clinical specimens of malignant pleural effusions.  相似文献   
94.
Aims: Isomalto‐oligosaccharides (IMO) with α(1→6) and α(1→4) glucosidic linkages are produced by enzymatic conversion of starch. IMO are only partially digestible but data on their influence on intestinal microbiota are limited. It was the aim of this study to investigate the effect of IMO diet on intestinal microbiota and short‐chain fatty acids production (SCFA) in rats. Methods and results: Three groups of F344 rats, each consisting of six animals, were fed IMO, inulin or a control diets for six weeks. A qualitative assessment of the intestinal microbiota was achieved by PCR‐denaturing gradient gel electrophoresis (DGGE). Major bacterial taxa were quantified by quantitative PCR (qPCR), and SCFA were measured using gas chromatography. Quantitative PCR demonstrated that lactobacilli were one of the dominant bacterial taxa in faecal samples from rats. IMO increased the number of lactobacilli and the total number of intestinal bacteria in rats fed IMO compared with animals receiving control and inulin diets. Furthermore, PCR‐DGGE with lactobacilli‐specific primers showed an altered biodiversity of lactobacilli in rats fed IMO compared with control diet. Conclusions: IMO selectively stimulates lactobacilli and increases their diversity in rats. Significance and impact of study: Isomalto‐oligosaccharides specifically stimulate growth of intestinal lactobacilli in a rat model system.  相似文献   
95.
Homeostatic eating cannot explain overconsumption of food and pathological weight gain. A more likely factor promoting excessive eating is food reward and its representation in the central nervous system (CNS). The anorectic hormones leptin and insulin reduce food reward and inhibit related CNS reward pathways. Conversely, the orexigenic gastrointestinal hormone ghrelin activates both homeostatic and reward-related neurocircuits. The current studies were conducted to identify in rats the effects of intracerebroventricular ghrelin infusions on two distinct aspects of food reward: hedonic valuation (i.e., "liking") and the motivation to self-administer (i.e., "wanting") food. To assess hedonic valuation of liquid food, lick motor patterns were recorded using lickometry. Although ghrelin administration increased energy intake, it did not alter the avidity of licking (initial lick rates or lick-cluster size). Several positive-control conditions ruled out lick-rate ceiling effects. Similarly, when the liquid diet was hedonically devalued with quinine supplementation, ghrelin failed to reverse the quinine-associated reduction of energy intake and avidity of licking. The effects of ghrelin on rats' motivation to eat were assessed using lever pressing to self-administer food in a progressive-ratio paradigm. Ghrelin markedly increased motivation to eat, to levels comparable to or greater than those seen following 24 h of food deprivation. Pretreatment with the dopamine D1 receptor antagonist SCH-23390 eliminated ghrelin-induced increases in lever pressing, without compromising generalized licking motor control, indicating a role for D1 signaling in ghrelin's motivational feeding effects. These results indicate that ghrelin increases the motivation to eat via D1 receptor-dependent mechanisms, without affecting perceived food palatability.  相似文献   
96.
97.

Objective

Musculodegenerative diseases threaten the life of many patients in the world. Since drug administration is not efficient in regeneration of damaged tissues, stem cell therapy is considered as a good strategy to restore the lost cells. Since the efficiency of myogenic differentiation potential of human Chorion- derived Mesenchymal Stem Cells (C-MSCs) has not been addressed so far; we set out to evaluate myogenic differentiation property of these cells in comparison with Umbilical Cord Blood- derived Mesenchymal Stem Cells (UCB-MSCs) in the presence of 5-azacytidine.

Materials & methods

To do that, neonate placenta Umbilical Cord Blood were transferred to the lab. After characterization of the isolated cells using flowcytometry and multilineage differentiation capacity, the obtained Mesenchymal Stem Cells were cultured in DMEM/F12 supplemented with 2% FBS and 10 μM of 5-azacytidine to induce myogenic differentiation. Real-time PCR and immunocytochemistry were used to assess the myogenic properties of the cells.

Results

Our data showed that C-MSCs and UCB-MSCs were spindle shape in morphology. They were positive for CD90, CD73 and CD44 antigens, and negative for hematopoietic markers. They also differentiated into osteoblast and adipoblast lineages. Real-time PCR results showed that the cells could express MyoD, desmin and α-MHC at the end of the first week (P < 0.05). No significant upregulation was detected in the expression of GATA-4 in both groups. Immunocytochemical staining revealed the expression of Desmin, cTnT and α-MHC.

Conclusions

Results showed that these cells are potent to differentiate into myoblast- like cells. An upregulation in the expression of some myogenic markers (desmin, α- MHC) was observed in C-MSCs in comparison with UCB-MSCs.  相似文献   
98.
99.
Collective motion and cannibalism in locust migratory bands   总被引:2,自引:0,他引:2  
Plagues of mass migrating insects such as locusts are estimated to affect the livelihood of one in ten people on the planet [1]. Identification of generalities in the mechanisms underlying these mass movements will enhance our understanding of animal migration and collective behavior while potentially contributing to pest-management efforts. We provide evidence that coordinated mass migration in juvenile desert locusts (Schistocerca gregaria) is influenced strongly by cannibalistic interactions. Individuals in marching bands tend to bite others but risk being bitten themselves. Reduction of individuals' capacity to detect the approach of others from behind through abdominal denervation (1) decreases their probability to start moving, (2) dramatically reduces the mean proportion of moving individuals in groups, and (3) significantly increases cannibalism. Similarly, occlusion of the rear visual field inhibits individuals' propensity to march. Abdomen denervation did not influence the behavior of isolated locusts. When within groups, abdominal biting and the sight of others approaching from behind triggers movement, creating an autocatalytic feedback that results in directed mass migration. This "forced march" driven by cannibalistic interactions suggests that we need to reassess our view of both the selection pressure and mechanism that can result in the coordinated motion of such large insect groups.  相似文献   
100.
We report DNA construction, baculovirus expression, and partial characterization of a minienzyme form of the human matrix metalloproteinase-9 (MMP-9). The MMP-9 minienzyme gene construct consisting of the pre, pro, and catalytic domains of the MMP-9 was introduced into Sf9 insect cells using a baculovirus expression system. The expression of the recombinant MMP-9 minienzyme was estimated to be approximately 0.8 mg/L of cell medium. The recombinant protein was purified using a single-step gelatin-Sepharose affinity column and yielded a highly stable and active minienzyme with gelatinolytic activity. Moreover, two interesting findings related to MMP-9 interactions with heparin and TIMP-1 resulted from our studies. First, the pro and catalytic domains of the human MMP-9 are not sufficient for heparin affinity. Second, in contrast to the prevailing consensus, TIMP-1 blockade of the enzymatic activity of MMP-9 does not require prior binding to the C-terminus of its MMP-9 protein substrate.  相似文献   
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