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991.
The malaria parasite Plasmodium vivax is known to be majorly endemic to Asian and Latin American countries with no or very few reports of Africans infected with this parasite. Since the human Duffy antigens act as receptors for P. vivax to invade human RBCs and Africans are generally Duffy-negative, non-endemicity of P. vivax in Africa has been attributed to this fact. However, recent reports describing P. vivax infections in Duffy-negative Africans from West and Central parts of Africa have been surfaced including a recent report on P. vivax infection in native Cameroonians. In order to know if Cameroonians living in the southern regions are also susceptible to P. vivax infection, we collected finger-prick blood samples from 485 malarial symptomatic patients in five locations and followed PCR diagnostic assays with DNA sequencing of the 18S ribosomal RNA gene. Out of the 201 malaria positive cases detected, 193 were pure P. falciparum, six pure P. vivax and two mixed parasite infections (P. falciparum + P. vivax). The eight P. vivax infected samples (six single + two mixed) were further subjected to DNA sequencing of the P. vivax multidrug resistance 1 (pvmdr1) and the P.vivax circumsporozoite (pvcsp) genes. Alignment of the eight Cameroonian pvmdr1 sequences with the reference sequence showed high sequence similarities, reconfirming P. vivax infection in all the eight patients. DNA sequencing of the pvcsp gene indicated all the eight P. vivax to be of VK247 type. Interestingly, DNA sequencing of a part of the human Duffy gene covering the promoter region in the eight P. vivax-infected Cameroonians to identify the T-33C mutation revealed all these patients as Duffy-negative. The results provide evidence of single P. vivax as well as mixed malaria parasite infection in native Cameroonians and add knowledge to the growing evidences of P. vivax infection in Duffy-negative Africans. 相似文献
992.
Shashank R. Joshi Ranjit Mohan Anjana Mohan Deepa Rajendra Pradeepa Anil Bhansali Vinay K. Dhandania Prashant P. Joshi Ranjit Unnikrishnan Elangovan Nirmal Radhakrishnan Subashini Sri Venkata Madhu Paturi Vishnupriya Rao Ashok Kumar Das Tanvir Kaur Deepak Kumar Shukla Viswanathan Mohan for the ICMR– INDIAB Collaborative Study Group 《PloS one》2014,9(5)
Aim
To study the pattern and prevalence of dyslipidemia in a large representative sample of four selected regions in India.Methods
Phase I of the Indian Council of Medical Research–India Diabetes (ICMR-INDIAB) study was conducted in a representative population of three states of India [Tamil Nadu, Maharashtra and Jharkhand] and one Union Territory [Chandigarh], and covered a population of 213 million people using stratified multistage sampling design to recruit individuals ≥20 years of age. All the study subjects (n = 16,607) underwent anthropometric measurements and oral glucose tolerance tests were done using capillary blood (except in self-reported diabetes). In addition, in every 5th subject (n = 2042), a fasting venous sample was collected and assayed for lipids. Dyslipidemia was diagnosed using National Cholesterol Education Programme (NCEP) guidelines.Results
Of the subjects studied, 13.9% had hypercholesterolemia, 29.5% had hypertriglyceridemia, 72.3% had low HDL-C, 11.8% had high LDL-C levels and 79% had abnormalities in one of the lipid parameters. Regional disparity exists with the highest rates of hypercholesterolemia observed in Tamilnadu (18.3%), highest rates of hypertriglyceridemia in Chandigarh (38.6%), highest rates of low HDL-C in Jharkhand (76.8%) and highest rates of high LDL-C in Tamilnadu (15.8%). Except for low HDL-C and in the state of Maharashtra, in all other states, urban residents had the highest prevalence of lipid abnormalities compared to rural residents. Low HDL-C was the most common lipid abnormality (72.3%) in all the four regions studied; in 44.9% of subjects, it was present as an isolated abnormality. Common significant risk factors for dyslipidemia included obesity, diabetes, and dysglycemia.Conclusion
The prevalence of dyslipidemia is very high in India, which calls for urgent lifestyle intervention strategies to prevent and manage this important cardiovascular risk factor. 相似文献993.
994.
Mrinalini Das Petros Isaakidis Rahul Shenoy Rey Anicete Hemant Kumar Sharma Imyangluba Ao Kaikho Osah Homa Mansoor Peter Saranchuk Sunita Abraham 《PloS one》2014,9(9)
Background
Multiple strategies are being adopted by national tuberculosis (TB) programmes to achieve universal coverage of tuberculosis treatment. However, populations living in ‘hard-to-reach’ areas of north-east India have poor access to health services. Our study aimed to detail treatment outcomes in TB program supported by Médecins Sans Frontières (MSF) and using an alternative model of TB treatment delivery in Mon district, Nagaland, India.Methods
This was a retrospective cohort study of TB patients, initiated on self-administered therapy (SAT) through Mon District Hospital, Nagaland, India between April 2012 and March 2013.Results
A total of 238 tuberculosis patients had final TB treatment outcomes during the study period, including 82 and 156 from semi-urban and rural areas respectively. The majority of patients (62%, 147/238) were suffering from pulmonary, smear-positive tuberculosis. Overall, 74% of patients (175/238) had successful outcomes, being cured or having completed their treatment. Females (81%), pulmonary TB patients (75%) and those on a Category I regimen (79%) had better treatment success rates than males (67%), extra-pulmonary TB patients (62%) and patients on a Category II regimen (61%). The univariate and bivariate analyses found age, sex and TB treatment regimen significantly associated with unsuccessful TB treatment outcomes (defined as death, loss-to-follow-up and failure). However, only older age showed significance in a multivariate binary logistic regression model.Conclusion
Our study suggests that self-administered TB treatment is feasible for patients living in areas with limited or no access to health services. The relatively low number of patients with adverse outcomes suggests that SAT models are safe; other advantages include the need for fewer resources and less frequent movements by patients. National TB programmes should consider allowing SAT strategies for delivery of TB treatment to ‘hard-to-reach’ populations, which could in turn help to achieve universal coverage and contribute to global TB elimination by 2050. 相似文献995.
In the Indian subcontinent, Leishmania donovani, the parasite causing visceral leishmaniasis (VL) is transmitted by the sand fly vector Phlebotomus argentipes. Long lasting insecticide treated nets (LN) have been postulated as alternative or complement to Indoor Residual Spraying but there are few field studies evaluating the entomological efficacy of different nets against this vector. We conducted two crossover trials in a VL endemic area in Nepal to compare the barrier effect of (1) LN with different mesh sizes (156 holes/inch2 vs 625 holes/inch2) and (2) alpha-cypermethrin treated LN and untreated nets having the same mesh size (156 holes/inch2). Each crossover trial had two arms consisting of a sequence of two different nets for 8 nights. We used 10 cattle sheds per trial. A cow placed under the net was used as bait. CDC light traps placed inside the nets were used to evaluate the number of P. argentipes crossing the net barrier. Negative binomial generalized estimating equation (GEE) population-averaged models adjusted by night and sequence were used to estimate the barrier effect of the different nets. The crossover trials conducted in a rural village in Morang district (South-eastern Nepal) demonstrated that reducing the size of the holes in treated nets (625 holes/inch2) increased the barrier effect of LN by 77% (95% confidence interval (CI): 56%–88%) compared with treated nets with larger holes (156 holes/inch2). Treating nets with alpha-cypermethrin reduced the number of P. argentipes captured inside the nets by 77% (95% CI: 27%–93%) compared with untreated nets. The effectiveness and acceptability of finer mesh pyrethroid treated LN should be tested for VL prevention in a randomized controlled trial. 相似文献
996.
Lorraine Iacovitti Xiaotao Wei Jingli Cai Eric W. Kostuk Ruihe Lin Alexander Gorodinsky Philip Roman Gretchen Kusek Sonal S. Das Audrey Dufour Terina N. Martinez Kuldip D. Dave 《PloS one》2014,9(12)
Parkinson disease (PD) is the second leading neurodegenerative disease in the US. As there is no known cause or cure for PD, researchers continue to investigate disease mechanisms and potential new therapies in cell culture and in animal models of PD. In PD, one of the most profoundly affected neuronal populations is the tyrosine hydroxylase (TH)-expressing dopaminergic (DA) neurons of the substantia nigra pars compacta (SNpc). These DA-producing neurons undergo degeneration while neighboring DA-producing cells of the ventral tegmental area (VTA) are largely spared. To aid in these studies, The Michael J. Fox Foundation (MJFF) partnered with Thomas Jefferson University and Taconic Inc. to generate new transgenic rat lines carrying the human TH gene promoter driving EGFP using a 11 kb construct used previously to create a hTH-GFP mouse reporter line. Of the five rat founder lines that were generated, three exhibited high level specific GFP fluorescence in DA brain structures (ie. SN, VTA, striatum, olfactory bulb, hypothalamus). As with the hTH-GFP mouse, none of the rat lines exhibit reporter expression in adrenergic structures like the adrenal gland. Line 12141, with its high levels of GFP in adult DA brain structures and minimal ectopic GFP expression in non-DA structures, was characterized in detail. We show here that this line allows for anatomical visualization and microdissection of the rat midbrain into SNpc and/or VTA, enabling detailed analysis of midbrain DA neurons and axonal projections after toxin treatment in vivo. Moreover, we further show that embryonic SNpc and/or VTA neurons, enriched by microdissection or FACS, can be used in culture or transplant studies of PD. Thus, the hTH-GFP reporter rat should be a valuable tool for Parkinson''s disease research. 相似文献
997.
Dhriti Chatterjee Sankar Addya Reas S. Khan Lawrence C. Kenyon Alexander Choe Randall J. Cohrs Kenneth S. Shindler Jayasri Das Sarma 《PloS one》2014,9(10)
Neurotropic recombinant strain of Mouse Hepatitis Virus, RSA59, induces meningo-encephalitis, myelitis and demyelination following intracranial inoculation. RSA59 induced neuropathology is partially caused by activation of CNS resident microglia, as demonstrated by changes in cellular morphology and increased expression of a microglia/macrophage specific calcium ion binding factor, Iba1. Affymetrix Microarray analysis for mRNA expression data reveals expression of inflammatory mediators that are known to be released by activated microglia. Microglia-specific cell surface molecules, including CD11b, CD74, CD52 and CD68, are significantly upregulated in contrast to CD4, CD8 and CD19. Protein analysis of spinal cord extracts taken from mice 6 days post-inoculation, the time of peak inflammation, reveals robust expression of IFN-γ, IL-12 and mKC. Data suggest that activated microglia and inflammatory mediators contribute to a local CNS microenvironment that regulates viral replication and IFN-γ production during the acute phase of infection, which in turn can cause phagolysosome maturation and phagocytosis of the myelin sheath, leading to demyelination. 相似文献
998.
Shadab Anwar Manas Ranjan Dikhit Krishn Pratap Singh Rajiv Kumar Kar Amir Zaidi Ganesh Chandra Sahoo Awadh Kishore Roy Tomoyoshi Nozaki Pradeep Das Vahab Ali 《PloS one》2014,9(10)
Iron-Sulfur (Fe-S) proteins are involved in many biological functions such as electron transport, photosynthesis, regulation of gene expression and enzymatic activities. Biosynthesis and transfer of Fe-S clusters depend on Fe-S clusters assembly processes such as ISC, SUF, NIF, and CIA systems. Unlike other eukaryotes which possess ISC and CIA systems, amitochondriate Entamoeba histolytica has retained NIF & CIA systems for Fe-S cluster assembly in the cytosol. In the present study, we have elucidated interaction between two proteins of E. histolytica CIA system, Cytosolic Fe-S cluster deficient 1 (Cfd1) protein and Nucleotide binding protein 35 (Nbp35). In-silico analysis showed that structural regions ranging from amino acid residues (P33-K35, G131-V135 and I147-E151) of Nbp35 and (G5-V6, M34-D39 and G46-A52) of Cfd1 are involved in the formation of protein-protein complex. Furthermore, Molecular dynamic (MD) simulations study suggested that hydrophobic forces surpass over hydrophilic forces between Nbp35 and Cfd1 and Van-der-Waal interaction plays crucial role in the formation of stable complex. Both proteins were separately cloned, expressed as recombinant fusion proteins in E. coli and purified to homogeneity by affinity column chromatography. Physical interaction between Nbp35 and Cfd1 proteins was confirmed in vitro by co-purification of recombinant Nbp35 with thrombin digested Cfd1 and in vivo by pull down assay and immunoprecipitation. The insilico, in vitro as well as in vivo results prove a stable interaction between these two proteins, supporting the possibility of its involvement in Fe-S cluster transfer to target apo-proteins through CIA machinery in E. histolytica. Our study indicates that initial synthesis of a Fe-S precursor in mitochondria is not necessary for the formation of Cfd1-Nbp35 complex. Thus, Cfd1 and Nbp35 with the help of cytosolic NifS and NifU proteins can participate in the maturation of non-mitosomal Fe-S proteins without any apparent assistance of mitosomes. 相似文献
999.
Keiji Uchiyama Hironori Miyata Masashi Yano Yoshitaka Yamaguchi Morikazu Imamura Naomi Muramatsu Nandita Rani Das Junji Chida Hideyuki Hara Suehiro Sakaguchi 《PloS one》2014,9(10)
Prion infection induces conformational conversion of the normal prion protein PrPC, into the pathogenic isoform PrPSc, in prion diseases. It has been shown that PrP-knockout (Prnp0/0) mice transgenically reconstituted with a mouse-hamster chimeric PrP lacking N-terminal residues 23-88, or Tg(MHM2Δ23-88)/Prnp0/0 mice, neither developed the disease nor accumulated MHM2ScΔ23-88 in their brains after inoculation with RML prions. In contrast, RML-inoculated Tg(MHM2Δ23-88)/Prnp0/+ mice developed the disease with abundant accumulation of MHM2ScΔ23-88 in their brains. These results indicate that MHM2Δ23-88 itself might either lose or greatly reduce the converting capacity to MHM2ScΔ23-88, and that the co-expressing wild-type PrPC can stimulate the conversion of MHM2Δ23-88 to MHM2ScΔ23-88 in trans. In the present study, we confirmed that Tg(MHM2Δ23-88)/Prnp0/0 mice remained resistant to RML prions for up to 730 days after inoculation. However, we found that Tg(MHM2Δ23-88)/Prnp0/0 mice were susceptible to 22L prions, developing the disease with prolonged incubation times and accumulating MHM2ScΔ23-88 in their brains. We also found accelerated conversion of MHM2Δ23-88 into MHM2ScΔ23-88 in the brains of RML- and 22L-inoculated Tg(MHM2Δ23-88)/Prnp0/+ mice. However, wild-type PrPSc accumulated less in the brains of these inoculated Tg(MHM2Δ23-88)/Prnp0/+ mice, compared with RML- and 22L-inoculated Prnp0/+ mice. These results show that MHM2Δ23-88 itself can convert into MHM2ScΔ23-88 without the help of the trans-acting PrPC, and that, irrespective of prion strains inoculated, the co-expressing wild-type PrPC stimulates the conversion of MHM2Δ23-88 into MHM2ScΔ23-88, but to the contrary, the co-expressing MHM2Δ23-88 disturbs the conversion of wild-type PrPC into PrPSc. 相似文献
1000.
Thermodynamic properties of a Yukawa system consisting of dust particles in plasma are studied in the presence of an external magnetic field. It is assumed that dust particles interact with each other by a modified potential in the presence of a magnetic field. A molecular dynamics code is developed to calculate this internal energy for the entire system. Based on the values of the internal energy given by the code, the Helmholtz free energy and pressure are calculated for the system. 相似文献