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251.
G. R. Gowane Najif Akram L. L. L. Prince Ved Prakash Arun Kumar 《Animal biotechnology》2017,28(4):306-314
India harbors a vast diversity of sheep (40 breeds). The study was carried out to assess the genetic diversity of DRB1 and DQA2 locus of the ovar-MHC and their possible association with Peste des petits ruminants (PPR) virus vaccine response in Malpura and Avikalin sheep breeds maintained at an organized institute flock in the semi-arid region of India. Genetic analysis revealed the rich diversity of DRB1 locus with 23 alleles in Malpura and 21 alleles in Avikalin sheep that included 9 new alleles. DQA2 locus also had rich diversity with 19 alleles in Malpura and 20 alleles in Avikalin sheep that included 7 new alleles. At the protein level, high variability alike at the nucleotide level was observed. A marker for footrot susceptibility, DQA2*1101 was absent in both breeds. Genotypic association of DRB1 and DQA2 with PPR vaccine response was statistically non-significant. Vaccine response being a multifactorial (polygenic and influenced by environment) variable, could not show statistically significant association with MHC genotypes in the present study. However, rich genetic diversity of DRB1 and DQA2 gene reflects the importance of this locus for future selection programs. 相似文献
252.
The aim of the present study was to investigate the effects of hypothyroidism induced during the pre- and postnatal periods of life on ovarian function and structure in offspring (pups) 120 days of age. Three groups were used. In the prenatal group, treatment was given from conception to parturition. In the postnatal group, treatment was given from parturition to 25 days postpartum. Hypothyroidism was induced by administration of 0.1% 6-n-propyl-2-thiouracil (PTU) in the drinking water of mothers. Body weights of the offspring were measured weekly. In each group, ten offspring were sacrificed at 120 days of age. Postnatal PTU treated pups showed delay in eye opening, teething, fur development, and weaning (35-37 days) compared to control animals (28-30 days). Body weight of offspring in the postnatal PTU treatment group was significantly decreased (P < 0.001), while the prenatal PTU treatment group showed a significant increase (P < 0.0001) compared to control animals. There was a significant (P < 0.05) reduction in paired ovarian weight of offspring in the postnatal PTU treatment group compared to control animals. Diameter of the ovaries was not affected by any treatment. Regarding the morphometery, only offspring in the prenatal PTU treatment group showed a significant (P < 0.001) increase in the diameter of graafian follicles. No significant difference was observed in morphometery of the granulosa layer, primary, and developing follicles of control and all treated groups. Number of primary, developing, and graafian follicles of all the treated groups was similar to that of the control group. The corpora lutea of the postnatal PTU treated group contained a population of large numbers of luteal cells compared to the control group. The prenatal PTU treated group did not exhibit a profound effect on ovarian morphology, histology, and morphometery. No difference was found in the serum estradiol concentration of control and PTU treated groups. J. Exp. Zool. 293:407-413, 2002. 相似文献
253.
Akram Abi Clarissa Müller Hans-Joachim Jördening 《Biotechnology and Bioprocess Engineering》2017,22(3):272-280
Laminaribiose phosphorylase (EC 2.4.1.31) catalyzes a reversible phosphorolysis reaction in which laminaribiose, a very high value sugar is produced. This enzyme is not being produced commercially therefore, to realize the most effective method for producing laminaribiose phosphorylase and obtaining as much activity units as possible per liter of culture, different cultivation methods of Euglena gracilis were compared. Heterotrophic and mixotrophic cultivations of Euglena gracilis in two different pHs, in flask and bioreactor were performed. The reverse phosphorolysis activity of laminaribiose phosphorylase produced under different cultivation methods was measured. The heterotrophic approach showed to be the more effective cultivation method as 47.6 IU/L was obtained compared to 27 IU/L in the mixotrophic one. The heterotrophic cultivation then was further investigated under two different pH values of the culture media. The culture at pH 6.8 resulted in 7.94 IU/L/day whereas only 4.06 was obtained for the culture at pH 4. Cultivation in a bioreactor resulted in a distinctive amount of 191.5 IU/L and an activity yield of 9.7 IU/g glucose compared to 5.4 in flask cultivation. Heterotrophic cultivation of Euglena gracilis in a bioreactor containing a culture media at pH 6.8 and controlled operation conditions showed enhanced laminaribiose phosphorylase activity production per liter and day of cultivation. 相似文献
254.
Bruno Maranhao Pooja Biswas Alexander D. H. Gottsch Mili Navani Muhammad Asif Naeem John Suk Justin Chu Sheen N. Khan Rachel Poleman Javed Akram Sheikh Riazuddin Pauline Lee S. Amer Riazuddin J. Fielding Hejtmancik Radha Ayyagari 《PloS one》2015,10(9)
Purpose
To define the molecular basis of retinal degeneration in consanguineous Pakistani pedigrees with early onset retinal degeneration.Methods
A cohort of 277 individuals representing 26 pedigrees from the Punjab province of Pakistan was analyzed. Exomes were captured with commercial kits and sequenced on an Illumina HiSeq 2500. Candidate variants were identified using standard tools and analyzed using exomeSuite to detect all potentially pathogenic changes in genes implicated in retinal degeneration. Segregation analysis was performed by dideoxy sequencing and novel variants were additionally investigated for their presence in ethnicity-matched controls.Results
We identified a total of nine causal mutations, including six novel variants in RPE65, LCA5, USH2A, CNGB1, FAM161A, CERKL and GUCY2D as the underlying cause of inherited retinal degenerations in 13 of 26 pedigrees. In addition to the causal variants, a total of 200 variants each observed in five or more unrelated pedigrees investigated in this study that were absent from the dbSNP, HapMap, 1000 Genomes, NHLBI ESP6500, and ExAC databases were identified, suggesting that they are common in, and unique to the Pakistani population.Conclusions
We identified causal mutations associated with retinal degeneration in nearly half of the pedigrees investigated in this study through next generation whole exome sequencing. All novel variants detected in this study through exome sequencing have been cataloged providing a reference database of variants common in, and unique to the Pakistani population. 相似文献255.
Schistosomes are long lived, intravascular parasitic platyhelminths that infect >200 million people globally. The molecular mechanisms used by these blood flukes to dampen host immune responses are described in this review. Adult worms express a collection of host-interactive tegumental ectoenzymes that can cleave host signaling molecules such as the “alarmin” ATP (cleaved by SmATPDase1), the platelet activator ADP (SmATPDase1, SmNPP5), and can convert AMP into the anti-inflammatory mediator adenosine (SmAP). SmAP can additionally cleave the lipid immunomodulator sphingosine-1-phosphate and the proinflammatory anionic polymer, polyP. In addition, the worms release a barrage of proteins (e.g., SmCB1, SjHSP70, cyclophilin A) that can impinge on immune cell function. Parasite eggs also release their own immunoregulatory proteins (e.g., IPSE/α1, omega1, SmCKBP) as do invasive cercariae (e.g., Sm16, Sj16). Some schistosome glycans (e.g., LNFPIII, LNnT) and lipids (e.g., Lyso-PS, LPC), produced by several life stages, likewise affect immune cell responses. The parasites not only produce eicosanoids (e.g., PGE2, PGD2—that can be anti-inflammatory) but can also induce host cells to release these metabolites. Finally, the worms release extracellular vesicles (EVs) containing microRNAs, and these too have been shown to skew host cell metabolism. Thus, schistosomes employ an array of biomolecules—protein, lipid, glycan, nucleic acid, and more, to bend host biochemistry to their liking. Many of the listed molecules have been individually shown capable of inducing aspects of the polarized Th2 response seen following infection (with the generation of regulatory T cells (Tregs), regulatory B cells (Bregs) and anti-inflammatory, alternatively activated (M2) macrophages). Precisely how host cells integrate the impact of these myriad parasite products following natural infection is not known. Several of the schistosome immunomodulators described here are in development as novel therapeutics against autoimmune, inflammatory, and other, nonparasitic, diseases. 相似文献
256.
Mohammed Kuddus Fahmida Khatoon Mohd Saleem Sadaf Anwar Syed Monowar Alam Shahid Tarig Ginawi Ashfaque Hossain Akram Abdullah Malaqi Alnabri Ziyad Fayez Alshammari Abdulaziz Mohammed Alrabie Sami Shayih Jehad Alenazi Motaz Monif F Alshammari Mohd Adnan Kausar 《Bioinformation》2021,17(5):541
Biocontaminants are minute particles derived from different biological materials. Indoor biocontaminants are associated with major public health problems. In Gulf countries, it is more precarious due to the harsh climatic conditions, including high ambient temperatures and relative humidity. In addition, due to COVID-19 pandemic, most of the time public is inside their home. Therefore, the aim of the study was to determine the load of biocontaminants in the indoor environment of Hail city. The results showed that most of the bacteria are gram-positive and higher in polymicrobial (87.1%) than monomicrobial (62.7%) association. There was no significant association with sample collection time and types of isolates. The most abundant microbes found in all samples were Staphylococcus aureus followed by Bacillus spp. Among Gram-negative bacterial isolates, E. coli was most common in tested indoor air samples. The study will be useful to find the biocontaminants associated with risk factors and their impact on human health in indoor environment, especially during the COVID-19 pandemic. These results indicate the need to implement health care awareness programs in the region to improve indoor air quality. 相似文献
257.
Abdolhossein Rustaiyan Akram Niknejad Lilly Nazarians Jasmin Jakupovic Ferdinand Bohlmann 《Phytochemistry》1982,21(7):1812-1813
The aerial parts of Salvia hypoleuca afforded two sesterterpenes with a previously unknown carbon skeleton. 相似文献
258.
Biofilm formation by Streptococcus mutans is considered as its principal virulence factor, causing dental caries. Mutants of S. mutans defective in biofilm formation were generated and analyzed to study the collective role of proteins in its formation. Mutants were characterized on the basis of adherence to saliva-coated surface, and biofilm formation. The confocal laser microscopy and scanning electron microscopy images showed that the control biofilms had cluster of cells covered by layer of exo-polysaccharide while the biofilms of mutants were thin and spaced. Two-dimensional protein electrophoresis data analysis identified 57 proteins that are either up (44 proteins) or down (13 proteins) regulated. These data points to the importance of up and down regulated proteins in the formation of biofilm in Streptococcus mutans. 相似文献
259.
Plant and Soil - Drought is the most significant factor limiting plant production in a majority of agricultural fields worldwide. PGPRs (plant growth promoting rhizobacteria) are beneficial soil... 相似文献
260.
Ommati Mohammad Mehdi Jamshidzadeh Akram Heidari Reza Sun Zilong Zamiri Mohammad Javad Khodaei Forouzan Mousapour Saeed Ahmadi Fatemeh Javanmard Nafiseh Shirazi Yeganeh Babak 《Biological trace element research》2019,187(1):151-162
Biological Trace Element Research - Lead (Pb)-induced reproductive toxicity is a well-characterized adverse effect associated with this heavy metal. It has been found that Pb exposure is associated... 相似文献