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101.
Alvarado-Esquivel C García-Machado C Alvarado-Esquivel D Vitela-Corrales J Villena I Dubey JP 《The Journal of parasitology》2012,98(2):271-273
The seroprevalence of Toxoplasma gondii infection in sheep (Ovis aries) in northern Mexico is largely unknown. Antibodies to T. gondii were determined in serum samples from 511 sheep from 8 farms in Durango State, Mexico, using the modified agglutination test (MAT). Sheep were raised in 3 geographical regions, i.e., mountainous (n = 68), semi-desert (n = 132), and valley (n = 311). Overall, T. gondii antibodies were found in 77 (15.1%) of 511 sheep, with MAT titers of 1∶25 in 27, 1∶50 in 10, 1∶100 in 11, 1∶200 in 11, 1∶400 in 8, 1∶800 in 3, 1∶1,600 in 4, and 1∶3,200 in 3. The seroprevalence of T. gondii infection increased significantly with age, indicating post-natal transmission. In contrast, gender, breed, flock size, and geographic region did not significantly influence the seroprevalence. Seropositive sheep were found in 7 of 8 farms sampled. This is the first report of T. gondii infection in sheep in Durango State, Mexico. Results indicate that infected sheep are probably an important source of T. gondii infection for humans in Durango State. 相似文献
102.
103.
García-Bocanegra I Cabezón O Arenas-Montes A Carbonero A Dubey JP Perea A Almería S 《Parasitology international》2012,61(3):421-424
Antibodies to Toxoplasma gondii were determined in serum samples from 616 equids (454 horses, 80 mules and 82 donkeys) in a cross-sectional study of 420 herds in Andalusia (Southern Spain), the region with the highest number of equids in Spain. Antibodies to T. gondii were found in 10.8% horses, 15.0% mules and 25.6% donkeys by using the modified agglutination test (MAT) at a cut-off of 1:25. Herd seroprevalence for horses, mules and donkeys was 14.7% (48/327), 23.9% (11/46) and 34.0% (16/47), respectively, and 75 herds (17.8%) had at least one seropositive animal. Significant differences in T. gondii seroprevalence were observed among species, with donkeys having the highest seroprevalence and horses the lowest (P=0.04). Seroprevalence was significantly higher in herds with presence of domestic ruminants. This study is the first report of the presence of T. gondii antibodies in equine species in Spain and the first reporting T. gondii infection in donkeys in Europe. The presence of antibodies is indication of contact with the parasite and therefore, consumption of equine meat could be a potential source of human infection in Spain. 相似文献
104.
Grover A Katiyar SP Jeyakanthan J Dubey VK Sundar D 《Journal of biomolecular structure & dynamics》2012,30(4):474-487
Leishmaniasis (1) is an endemic disease mainly caused by the protozoan Leishmania donovani (Ld). Polyamines have been identified as essential organic compounds for the growth and survival of Ld. These are synthesized in Ld by polyamine synthesis pathway comprising of many enzymes such as ornithine decarboxylase (ODC), spermidine synthase (SS), and S-adenosylmethionine decarboxylase. Inhibition of these enzymes in Ld offers a viable prospect to check its growth and development. In the present work, we used computational approaches to search natural inhibitors against ODC and SS enzymes. We predicted three-dimensional structures of ODC and SS using comparative modeling and molecular dynamics (MD) simulations. Thousands of natural compounds were virtually screened against target proteins using high throughput approach. MD simulations were then performed to examine molecular interactions between the screened compounds and functional residues of the active sites of the enzymes. Herein, we report two natural compounds of dual inhibitory nature active against the two crucial enzymes of polyamine pathway of Ld. These dual inhibitors have the potential to evolve as lead molecules in the development of antileishmanial drugs. (1)These authors contributed equally. 相似文献
105.
Dubey A Boukouvala F Keyvan G Hsia R Saranteas K Brone D Misra T Ierapetritou MG Muzzio FJ 《AAPS PharmSciTech》2012,13(1):231-246
A combination of analytical and statistical methods is used to improve a tablet coating process guided by quality by design
(QbD) principles. A solid dosage form product was found to intermittently exhibit bad taste. A suspected cause was the variability
in coating thickness which could lead to the subject tasting the active ingredient in some tablets. A number of samples were
analyzed using a laser-induced breakdown spectroscopy (LIBS)-based analytical method, and it was found that the main variability
component was the tablet-to-tablet variability within a lot. Hence, it was inferred that the coating process (performed in
a perforated rotating pan) required optimization. A set of designed experiments along with response surface modeling and kriging
method were used to arrive at an optimal set of operating conditions. Effects of the amount of coating imparted, spray rate,
pan rotation speed, and spray temperature were characterized. The results were quantified in terms of the relative standard
deviation of tablet-averaged LIBS score and a coating variability index which was the ratio of the standard deviation of the
tablet-averaged LIBS score and the weight gain of the tablets. The data-driven models developed based on the designed experiments
predicted that the minimum value of this index would be obtained for a 6% weight gain for a pan operating at the highest speed
at the maximum fill level while using the lowest spraying rate and temperature from the chosen parametric space. This systematic
application of the QbD-based method resulted in an enhanced process understanding and reducing the coating variability by
more than half. 相似文献
106.
Prashant Digpal S. Gour Prem P. Dubey Anubhav Jain Subhash C. Gupta Balwinder K. Joshi Dinesh Kumar 《Journal of applied genetics》2008,49(4):379-381
Sex determination in domestic animals is of potential value to livestock breeding programs. The aim of this study was to develop a simple and accurate PCR-based sex determination protocol, which can be applicable to 6 major domesticated species of the family Bovidae,viz. Bos frontalis, B. grunniens, B. indicus, Bubalus bubalis, Capra hircus, andOvis aries. In silico analysis was done to identify conserved DNA sequence in the HMG box region of the sex-determining region of the Y-chromosome (SRY gene) across the bovids. Duplex PCR assay, including theSRY gene and theGAPDH housekeeping gene, was optimized by using genomic DNA extracted from blood samples of known sex. It was possible to identify the sex of animals by amplifying both gender-specific (SRY) and autosomal (GAPDH) genes simultaneously in the duplex reaction, with the male yielding two bands and the female one band. The protocol was subjected to a blind test that showed a 100 percent specificity and accuracy, thus it can be used in sex determination in livestock breeding programs. 相似文献
107.
Cenchrus (family Poaceae) is an important component of major grass covers of the world. Largely it is apomictic and both annual and perennial species
exist in nature. Variations in contents of malondialdehyde, proline, specific leaf area and carbon isotope discrimination
for drought tolerance were estimated among eight prominent species of Cenchrus. Simultaneously, genetic variations were also estimated by employing 187 RAPD primers. Of these, 23 primers did not react,
2 performed poorly and 7 produced many non-scorable bands and one primer yielded a single monomorphic band. Rest of the 154
primers generated one or more unambiguously scorable fragments. Twelve hundred and four of the 1,296 putative loci were polymorphic
(93%) between at least one pair-wise comparisons among eight species. Dice coefficient and neighbor-joining algorithm analyses
showed clustering patterns that fit with the known habitat of the species except perennial, C. myosuroides which formed a node between two annuals species. When these species were subjected to water stress tolerance test, a correlation
(r = 0.612) between specific leaf area (SLA) and carbon isotope discrimination (CID) and difference in levels of drought tolerance
based parameters among eight species were observed. Of the eight species investigated two annuals viz., C. biflorus and C. echinatus showed highest level of genetic similarity which was also evident from the similar levels of SLA, MDA, proline contents and
carbon isotope discrimination values observed in these two species. 相似文献
108.
Raj Kumar Koiri Surendra Kumar Trigun Santosh Kumar Dubey Santosh Singh Lallan Mishra 《Biometals》2008,21(2):117-126
Metal complex–protein interaction is an evolving concept for determining cellular targets of metallodrugs. Lacatate dehydrogenase
(LDH) is critically implicated in tumor growth and therefore, considered to be an important target protein for anti-tumor
metal complexes. Due to efficient biocompatibility of copper (Cu2+) and zinc (Zn2+), we synthesized CubpyAc2 · H2O (Cu-bpy) and ZnbpyAc2 · H2O (Zn-bpy; where bpy = 2,2′ bipyridine, Ac = CH3COO−) complexes and evaluated their interaction with and modulation of LDH in mouse tissues. The increasing concentration of both
the complexes showed a significant shift in UV–Vis spectra of LDH. The binding constant data (Kc = 1 × 103 M−1 for Cu-bpy and 7 × 106 M−1 for Zn-bpy) suggested that Zn-bpy-LDH interaction is stronger than that of Cu-bpy-LDH. LDH modulating potential of the complexes
were monitored by perfusing the mice tissues with non-toxic doses of Cu-bpy and Zn-bpy followed by activity measurement and
analysis of LDH isozymes on non-denaturing polyacrylamide gel electrophoresis (PAGE). As compared to the control sets, Cu-bpy
caused a significant decline (P < 0.05–0.001) in the activity of LDH in all the tissues studied. However, Zn-bpy showed inhibition of LDH only in liver (P < 0.01), kidney (P < 0.001) and heart (P < 0.01), but with no effect in spleen, brain and skeletal muscle tissues. PAGE analysis suggested that all the five LDH isozymes
are equally sensitive to both the complexes in the respective tissues. The results suggest that Cu- and Zn-bpy are able to
interact with and inhibit LDH, a tumor growth supportive target protein at tissue level. 相似文献
109.
Helen Baines Margaret O Nwagwu Graham R Hastie Roman A Wiles Terry M Mayhew Francis JP Ebling 《Reproductive biology and endocrinology : RB&E》2008,6(1):4
Background
The hypogonadal (hpg) mouse is widely used as an animal model with which to investigate the endocrine regulation of spermatogenesis. Chronic treatment of these GnRH-deficient mice with estradiol is known to induce testicular maturation and restore qualitatively normal spermatogenesis. The aim of the current studies was to investigate whether these effects of estradiol are direct effects in the testis, or indirect actions via paradoxical stimulation of FSH secretion from the pituitary gland. 相似文献110.
Celine Scornavacca Vincent Berry Vincent Lefort Emmanuel JP Douzery Vincent Ranwez 《BMC bioinformatics》2008,9(1):413