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491.
Sang Hyun Park Keeseon S. Eom Min Sun Park Oh Kyoung Kwon Hyo Sun Kim Jai Hoon Yoon 《The Korean journal of parasitology》2013,51(4):471-473
Diphyllobothrium nihonkaiense has been reported in Korea as Diphyllobothrium latum because of their close morphologic resemblance. We have identified a human case of D. nihonkaiense infection using the mitochondrial cytochrome c oxidase subunit I (cox1) gene sequence analysis. On 18 February 2012, a patient who had consumed raw fish a month earlier visited our outpatient clinic with a long tapeworm parasite excreted in the feces. The body of the segmented worm was 2 m long and divided into the scolex (head) and proglottids. It was morphologically close to D. nihonkaiense and D. latum. The cox1 gene analysis showed 99.4% (340/342 bp) homology with D. nihonkaiense but only 91.8% (314/342 bp) homology with D. latum. The present study suggested that the Diphyllobothrium spp. infection in Korea should be analyzed with specific DNA sequence for an accurate species identification. 相似文献
492.
Neena Srivastava Jai Prakash Apurva Srivastava Chandra Gupta Agarwal Deep Chandra Pant Balraj Mittal 《Indian journal of human genetics》2013,19(1):26-31
BACKGROUND:
Over the last few decades, obesity, diabetes, and hypertension have become main health evils. The health problems of obesity are well-recognized. However, the fact that all obese individuals are not at the same risk of developing a disease is also recognized. The apolipoprotein B (APOB) plays a central role in lipid metabolism. So we compare the association of APOB XbaI gene polymorphism and lipid profile total in obese north Indian population.MATERIALS AND METHODS:
A total of 132 obese (body mass index [BMI] >25 kg/m2) and 132 age matched non-obese (BMI ≤ 25 kg/m2) subjects were studied after taking detailed clinical profile. Lipid profile in serum/plasma was done using commercial kits. Genetic analysis of APOB XbaI was done using Polymerase Chain Reaction-Restriction Fragment Leanth polymorphism (PCR-RFLP).STATISTICAL ANALYSIS:
Statistical analysis was performed by Statistical Package for the Social Sciences (SPSS) (version 11.5) software (IBM Corporation). All continuous variables were expressed as mean ± SD and tested by analysis of variance test. Comparisons of categorical variables were assessed using χ2 tests or Fisher''s exact test. P < 0.05 was considered as significant.RESULTS:
Analysis showed that obese subjects had significantly higher value of the waist-to-hip ratio, blood pressure (systolic and diastolic), and lipid profile. In APOB XbaI gene polymorphism, we did not find significant differences in genotype or allele frequencies. Moreover, none of the studied metabolic parameters (lipid profile) showed any association with the gene polymorphism.CONCLUSIONS:
Study reveals no considerable association of APOB XbaI gene polymorphism with obesity and lipid profile in north Indians. 相似文献493.
494.
Indira Singh Chauhan G. Subba Rao Jai Shankar Lalit Kumar Singh Chauhan Govind J. Kapadia Neeloo Singh 《Parasitology international》2018,67(5):627-636
Curcumin is the major phenolic compound found in turmeric, a dry powder of rhizomes and roots of the plant, Curcuma longa L., which is widely used as spice and food colorant around the world, and in herbal medicinal practice in Asian countries. The present study reports the leishmanicidal activity of trans-dibenzalacetone (DBA), a synthetic monoketone analog of curcumin, against Leishmania donovani parasites. We for the first time report the antiproliferative effect of a curcumin analog (DBA) on the intracellular amastigotes of L. donovani, the clinically more relevant stage of the parasite than its promastigotes stage. The leishmanicidal effect of DBA was further confirmed by scanning and transmission electron microscopies. Cell growth was arrested in G0/G1 phase with increased concentration of cytosolic calcium and dissipation of mitochondrial membrane potential. Further, the unique trypanothione/trypanothione reductase (TR) system of Leishmania cells was significantly inhibited by DBA. This economically synthesizable simple monoketone analog of curcumin has the potential for field use against visceral leishmaniasis which is currently widespread in tropical and subtropical developing countries of the world. In conclusion, we have identified an analog of curcumin for potential applications against leishmaniasis, based on its strong antiparasitic activity and low toxicity. This curcumin analog compares favorably, at least in vitro, with the existing medication miltefosine. 相似文献
495.
Shainaba A Saadhali Sameer Hassan Luke Elizabeth Hanna Uma Devi Ranganathan Vanaja Kumar 《Journal of molecular modeling》2016,22(8):180
Mycobacteriophages produce lysins that break down the host cell wall at the end of lytic cycle to release their progenies. The ability to lyse mycobacterial cells makes the lysins significant. Mycobacteriophage Che12 is the first reported temperate phage capable of infecting and lysogenising Mycobacterium tuberculosis. Gp11 of Che12 was found to have Chitinase domain that serves as endolysin (lysin A) for Che12. Structure of gp11 was modeled and evaluated using Ramachandran plot in which 98 % of the residues are in the favored and allowed regions. Che12 lysin A was predicted to act on NAG-NAM-NAG molecules in the peptidoglycan of cell wall. The tautomers of NAG-NAM-NAG molecule were generated and docked with lysin A. The stability and binding affinity of lysin A – NAG-NAM-NAG tautomers were studied using molecular dynamics simulations. 相似文献
496.
Prasad?S. Sarangapani Steven?D. Hudson Ronald?L. Jones Jack?F. Douglas Jai?A. Pathak 《Biophysical journal》2015,108(3):724-737
Recent studies of globular protein solutions have uniformly adopted a colloidal view of proteins as particles, a perspective that neglects the polymeric primary structure of these biological macromolecules, their intrinsic flexibility, and their ability to sample a large configurational space. While the colloidal perspective often serves as a useful idealization in many cases, the macromolecular identity of proteins must reveal itself under thermodynamic conditions in which the native state is no longer stable, such as denaturing solvents and high protein concentrations where macromolecules tend to have screened excluded volume, charge, and hydrodynamic interactions. Under extreme pH conditions, charge repulsion interactions within the protein chain can overcome the attractive hydrogen-bonding interactions, holding it in its native globular state. Conformational changes can therefore be expected to have great significance on the shear viscosity and other rheological properties of protein solutions. These changes are not envisioned in conventional colloidal protein models and we have initiated an investigation of the scattering and rheological properties of model proteins. We initiate this effort by considering bovine serum albumin because it is a globular protein whose solution properties have also been extensively investigated as a function of pH, temperature, ionic strength, and concentration. As we anticipated, near-ultraviolet circular dichroism measurements and intrinsic viscosity measurements clearly indicate that the bovine serum albumin tertiary structure changes as protein concentration and pH are varied. Our findings point to limited validity of the colloidal protein model and to the need for further consideration and quantification of the effects of conformational changes on protein solution viscosity, protein association, and the phase behavior. Small-angle Neutron Scattering measurements have allowed us to assess how these conformational changes influence protein size, shape, and interprotein interaction strength. 相似文献
497.
498.
Christopher D Adams WP Lee DS Morgan B Pan Z Singh GJ Tsong Y Lyapustina S 《AAPS PharmSciTech》2007,8(1):E39-E48
The purpose of this article is to present the thought process, methods, and interim results of a PQRI Working Group, which
was charged with evaluating the chi-square ratio test as a potential method for determining in vitro equivalence of aerodynamic
particle size distribution (APSD) profiles obtained from cascade impactor measurements. Because this test was designed with
the intention of being used as a tool in regulatory review of drug applications, the capability of the test to detect differences
in APSD profiles correctly and consistently was evaluated in a systematic way across a designed space of possible profiles.
To establish a “base line,” properties of the test in the simplest case of pairs of identical profiles were studied. Next,
the test's performance was studied with pairs of profiles, where some difference was simulated in a systematic way on a single
deposition site using realistic product profiles. The results obtained in these studies, which are presented in detail here,
suggest that the chi-square ratio test in itself is not sufficient to determine equivalence of particle size distributions.
This article, therefore, introduces the proposal to combine the chi-square ratio test with a test for impactor-sized mass
based on Population Bioequivalence and describes methods for evaluating discrimination capabilities of the combined test.
The approaches and results described in this article elucidate some of the capabilities and limitations of the original chi-square
ratio test and provide rationale for development of additional tests capable of comparing APSD profiles of pharmaceutical
aerosols.
Published: January 19, 2007 相似文献
499.
Joo Chuan Tong Zong Hong Zhang J Thomas August Vladimir Brusic Tin Wee Tan Shoba Ranganathan 《Immunome research》2007,3(1):1-8
Background
Arenaviruses are a family of rodent-borne viruses that cause several hemorrhagic fevers. These diseases can be devastating and are often lethal. Herein, to aid in the design and development of diagnostics, treatments and vaccines for arenavirus infections, we have developed a database containing protein sequences from the seven pathogenic arenaviruses (Junin, Guanarito, Sabia, Machupo, Whitewater Arroyo, Lassa and LCMV).Results
The database currently contains a non-redundant set of 333 protein sequences which were manually annotated. All entries were linked to NCBI and cited PubMed references. The database has a convenient query interface including BLAST search. Sequence variability analyses were also performed and the results are hosted in the database.Conclusion
The database is available at http://epitope.liai.org:8080/projects/arena and can be used to aid in studies that require proteomic information from pathogenic arenaviruses. 相似文献500.
Endoplasmic reticulum (ER) stress signaling can be mediated by the ER kinase PERK, which phosphorylates its substrate eIF2alpha. This in turn, results in translational repression and the activation of downstream programs that can limit cell growth through cell cycle arrest and/or apoptosis. These responses can also be initiated by perturbations in cell adhesion. Thus, we hypothesized that adhesion-dependent regulation of PERK signaling might determine cell fate. We tested this hypothesis in a model of mammary acini development, a morphogenetic process regulated in part by adhesion signaling. Here we report a novel role for PERK in limiting MCF10A mammary epithelial cell proliferation during acinar morphogenesis in 3D Matrigel culture as well as in preventing mammary tumor formation in vivo. We show that loss of adhesion to a suitable substratum induces PERK-dependent phosphorylation of eIF2alpha and selective upregulation of ATF4 and GADD153. Further, inhibition of endogenous PERK signaling during acinar morphogenesis, using two dominant-negative PERK mutants (PERK-DeltaC or PERK-K618A), does not affect apoptosis but results instead in hyper-proliferative and enlarged lumen-filled acini, devoid of proper architecture. This phenotype correlated with an adhesion-dependent increase in translation initiation, Ki67 staining and upregulation of Laminin-5, ErbB1 and ErbB2 expression. More importantly, the MCF10A cells expressing PERKDeltaC, but not a vector control, were tumorigenic in vivo upon orthotopic implantation in denuded mouse mammary fat pads. Our results reveal that the PERK pathway is responsive to adhesion-regulated signals and that it is essential for proper acinar morphogenesis and in preventing mammary tumor formation. The possibility that deficiencies in PERK signaling could lead to hyperproliferation of the mammary epithelium and increase the likelihood of tumor formation, is of significance to the understanding of breast cancer. 相似文献