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101.
Amphotericin B (AmB) liposome formulations are very successful in the treatment of fungal infections and leishmaniasis. But higher cost limits its widespread use among people in developing countries. Therefore, we have developed a modified ethanol-injection method for the preparation of AmB liposomes. Two liposomal formulations were developed with dimyristoyl phosphatidylcholine [F-1a] and soya phosphatidylcholine [F-2a], along with egg phosphatidyl glycerol and cholesterol. AmB was dissolved in acidified dimethyl acetamide and mixed with ethanolic lipid solution and rapidly injected in 5% dextrose to prepare liposomes. Liposomes were characterized on the basis of size (~100?nm), zeta (-43.3?±?2.8 mV) and percent entrapment efficiency (>95%). The in vitro release study showed an insignificant difference (P?≥?0.05) for 24-hour release between marketed AmB liposomes (AmBisome) and F-1a and F-2a. Proliposome concentrate, used for the preparation of in situ liposomes, was physically stable for more than 3 months at experimental conditions. Similarly, AmB showed no sign of degradation in reconstituted liposomes stored at 2-8°C for more than 3 months. IC(50) value of Ambisome (0.18 μg/mL) was comparatively similar to F-1a (0.17 μg/mL) and F-2a (0.16 μg/mL) against intramacrophagic amastigotes. Under experimental conditions, a novel modified method for AmB liposomes is a great success and generates interest for development as a platform technology for many therapeutic drug products. 相似文献
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Singh HS Saksena D Meitei SY Murry B Mondal PR Sachdeva MP Ghosh PK Saraswathy KN 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2012,69(1):97-106
Haptoglobin (HP) is a serum protein that has the capability of binding the extracorpuscular haemoglobin released during haemolysis. It plays an important role in protection of haemolytic disease by reducing the oxidative and peroxidative potential at free haemoglobin. The present study was aimed to determine the prevalence of HP polymorphism among different Indian populations, anthropologically belonging to diverse ethnicity. The polymorphism was screened among 642 unrelated individuals belonging to 14 population groups of India including both tribal and non-tribal caste groups from different geographical regions of India with distinct linguistic affiliations. An attempt is also made to understand the distribution of HP polymorphism among the studied populations. The result reveals the HP gene to be polymorphic in all the studied populations. Except the two tribal populations (Thotis of Andhra Pradesh and Patelias of Rajasthan) and one caste population (Rajput of Himachal Pradesh), all the studied populations are found to obey the Hardy-Weinberg equilibrium. The significance of the present study is elucidated with the prevalence of high mutant HP*2 allele frequency in India. Selection could be one of the most plausible explanations for this high HP frequency because of its uniformly high occurrence among all the studied populations. 相似文献
104.
P Minakshi R Singh K Ranjan P Kumar CG Joshi YK Reddy G Prasad 《Journal of virology》2012,86(15):8337-8338
In this article, we document the first complete genome sequence of an isolate of bluetongue virus serotype 16 (BTV16) from a goat in India. The virus was isolated from an in-contact goat from an animal farm in Chennai where clinical disease occurs in sheep. The total size of the genome is 19,185 bp. The information provided for full-length sequences of all 10 segments will help in understanding the geographical origin and transmission of the Indian isolate of BTV16 as well as its comparison with global isolates of BTV16 of sheep, cattle, and other host species origins. 相似文献
105.
Biswas A Si D Al Nasr K Ranjan D Zubair M He J 《Journal of bioinformatics and computational biology》2012,10(3):1242006
The determination of the secondary structure topology is a critical step in deriving the atomic structure from the protein density map obtained from electron cryo-microscopy technique. This step often relies on the matching of two sources of information. One source comes from the secondary structures detected from the protein density map at the medium resolution, such as 5-10 ?. The other source comes from the predicted secondary structures from the amino acid sequence. Due to the inaccuracy in either source of information, a pool of possible secondary structure positions needs to be sampled. This paper studies the question, that is, how to reduce the computation of the mapping when the inaccuracy of the secondary structure predictions is considered. We present a method that combines the concept of dynamic graph with our previous work of using constrained shortest path to identify the topology of the secondary structures. We show a reduction of 34.55% of run-time as comparison to the na?ve way of handling the inaccuracies. We also show an improved accuracy when the potential secondary structure errors are explicitly sampled verses the use of one consensus prediction. Our framework demonstrated the potential of developing computationally effective exact algorithms to identify the optimal topology of the secondary structures when the inaccuracy of the predicted data is considered. 相似文献
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This study was undertaken to determine age and sex variations in the prevalence of underweight and stunting, and to assess the impact of some socio-economic variables on undernutrition among 6–16 year old school children of Bengalee ethnicity in Chapra, West Bengal, India. The subjects were selected randomly from various schools and madrassas of the Chapra Block. A total of 725 children (342 boys and 383 girls) aged 6–16 years were measured and data on their socio-economic status were collected. Age and sex combined rates of underweight and stunting were 44.40% and 37.20%, respectively. Weight-for-age Z-score (WAZ) showed significant association with per-capita income (PCI) among boys (F = 5.45) and girls (F = 8.14). Height-for-age Z-score (HAZ) has also shown the association with per-capita income among boys (F = 4.43) and girls (F = 9.69). The WAZ was significantly associated with fathers’ educational status (FOS) (t = ?2.95) and the number of living rooms (NLR) (t = ?2.91) among girls. The HAZ showed significant association with number of siblings (NS) among girls (F = 4.25). Linear regression analyses revealed that NLR (t = 2.04) and NS (t = 1.95) had a significant impact on HAZ among boys. Among girls, PCI (t = 3.38), FOS (t = 2.87) and NLR (t = 2.81) had a significant impact on WAZ and also PCI (t = 3.28) and FOS (t = 2.90) had a significant impact on HAZ. NLR had significant associations with underweight (χ2 = 3.59) and stunting (χ2 = 4.20) among boys. Among girls, PCI had significant associations with underweight (χ2 = 11.15) and stunting (χ2 = 11.64). FOS also showed significant associations with underweight (χ2 = 8.10) as well as stunting (χ2 = 8.28) among girls. NLR showed a significant association with underweight (χ2 = 7.75). Logistics regression analyses revealed that FOS (Wald = 8.00) and NLR (Wald = 4.09) were significant predictors of stunting among boys. Among girls, PCI was a significant predictor of underweight (Wald = 10.95) as well as stunting (Wald = 10.45). FOS, NLR and NS were also significant predictors of stunting (Wald = 8.16), underweight (Wald = 7.68) and stunting (Wald = 6.97) respectively. The present study revealed that the nutritional status of the children was unsatisfactory and it is of paramount importance not only to increase the amount of food supplementation given but also to promote gender equality. 相似文献
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M Maheshwari A Samanta SK Godavarthi R Mukherjee NR Jana 《The Journal of biological chemistry》2012,287(35):29949-29957
Huntington disease (HD) is a hereditary neurodegenerative disorder characterized by progressive cognitive, psychiatric, and motor symptoms. The disease is caused by abnormal expansion of CAG repeats in the gene encoding huntingtin, but how mutant huntingtin leads to early cognitive deficits in HD is poorly understood. Here, we demonstrate that the ubiquitin ligase Ube3a, which is implicated in synaptic plasticity and involved in the clearance of misfolded polyglutamine protein, is strongly recruited to the mutant huntingtin nuclear aggregates, resulting in significant loss of its functional pool in different regions of HD mouse brain. Interestingly, Arc, one of the substrates of Ube3a linked with synaptic plasticity, is also associated with nuclear aggregates, although its synaptic level is increased in the hippocampus and cortex of HD mouse brain. Different regions of HD mouse brain also exhibit decreased levels of AMPA receptors and various pre- and postsynaptic proteins, which could be due to the partial loss of function of Ube3a. Transient expression of mutant huntingtin in mouse primary cortical neurons further demonstrates recruitment of Ube3a into mutant huntingtin aggregates, increased accumulation of Arc, and decreased numbers of GluR1 puncta in the neuronal processes. Altogether, our results suggest that the loss of function of Ube3a might be associated with the synaptic abnormalities observed in HD. 相似文献
110.