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311.
Maharjan Rukesh Khan Arif Iftikhar Nadeem-ul-Haque Muhammad Maresca Marc Choudhary M. Iqbal Shaheen Farzana Simjee Shabana U. 《Probiotics and antimicrobial proteins》2022,14(2):391-405
Probiotics and Antimicrobial Proteins - Anti-microbial peptides (AMPs) have attracted major attention due to their potential bio-activities against some multidrug resistant pathogens. The present... 相似文献
312.
Mehran Akhtar Suleman Khan Yasir Ali Shohra Haider Jalal ud Din Zia-ul Islam Fazal Jalil 《Saudi Journal of Biological Sciences》2020,27(12):3354-3358
C-C Chemokine receptor 6 (CCR6), an important protein in inflammatory and immunological responses, has been previously reported to be associated with rheumatoid arthritis (RA). Therefore, in order to replicate these findings, a case-control study was conducted on 500 subjects (including 250 RA patients and 250 healthy controls) of Pakistani origin. The aim of this study was to determine the association of CCR6 rs3093024 variant with RA and identify its role in splicing events using bioinformatics tools. The clinical and demographic characteristics of the patients were collected using a well-designed questionnaire. The genotype frequencies of CCR6 rs3093024 variant were determined using tetra-primer ARMS-PCR (amplification of refractory mutation system-polymerase chain reaction) method. A significant difference was found between CCR6 rs3093024 genotype frequencies [P = 0.0016, χ2 = 12.915]. Similarly, a significant difference in the allele frequencies between RA patients and healthy controls was also observed [P = 0.0003 and OR (95% CI) = 0.63 (0.49–0.80)]. The stratification of patients showed that there was a significant increase in AA genotype against AG + GG in patients [P = 0.0014, OR (95% CI) = 2.0 (1.32–3.02)]. Furthermore, using bioinformatics analysis, it was found that CCR6 rs3093024 variant might create a potential splicing enhancer motif (SF2/ASF (IgM-BRCA1) with score of 77.92; Threshold 70.53), which might have important impact on the product of this gene. This study suggests that the A variant of CCR6 rs3093024 variant is significantly associated with RA-risk and its G variant is protective in Pakistani population but a multi-cohort large sized population study is needed to elucidate these results. Moreover, functional studies are needed to highlight the effects of this polymorphism on the function of CCR6 gene. 相似文献
313.
Quantitative trait loci (QTL) detection was carried out for adventitious rooting and associated propagation traits in a second-generation
outbred Corymbia torelliana × Corymbia citriodora subspecies variegata hybrid family (n = 186). The parental species of this cross are divergent in their capacity to develop roots adventitiously on stem cuttings
and their propensity to form lignotubers. For the ten traits studied, there was one or two QTL detected, with some QTL explaining
large amounts of phenotypic variation (e.g. 66% for one QTL for percentage rooting), suggesting that major effects influence
rooting in this cross. Collocation of QTL for many strongly genetically correlated rooting traits to a single region on linkage
group 12 suggested pleiotropy. A three locus model was most parsimonious for linkage group 12, however, as differences in
QTL position and lower genetic correlations suggested separate loci for each of the traits of shoot production and root initiation.
Species differences were thought to be the major source of phenotypic variation for some rooting rate and root quality traits
because of the major QTL effects and up to 59-fold larger homospecific deviations (attributed to species differences) relative
to heterospecific deviations (attributed to standing variation within species) evident at some QTL for these traits. A large
homospecific/heterospecific ratio at major QTL suggested that the gene action evident in one cross may be indicative of gene
action more broadly in hybrids between these species for some traits. 相似文献
314.
The cellulose-binding domain of endoglucanase A (CenA) from Cellulomonas fimi: evidence for the involvement of tryptophan residues in binding 总被引:7,自引:1,他引:6
Neena Din Ian J. Forsythe Leslie D. Burtnick Neil R. Gilkes Robert C. Miller Jr R. Antony J. Warren Douglas G. Kilburn 《Molecular microbiology》1994,11(4):747-755
Cellulomonas fimi endo-β-1, 4-glucanase A (CenA) contains a discrete N-terminal cellulose-binding domain (CBDcenA)- Related CBDs occur In at least 16 bacterial glycanases and are characterized by four highly conserved Trp residues, two of which correspond to W14 and W68 of CBDcenA- The adsorption of CBDcenA to Crystalline cellulose was compared with that of two Trp mutants (W14A and W68A). The affinities of the mutant CBDs for cellulose were reduced by approximately 50- and 30-fold, respectively, relative to the wild type. Physical measurements indicated that the mutant CBDs fold normally. Fluorescence data indicated that W14 and W68 were exposed on the CBD, consistent with their participation in binding to cellobiosyl residues on the cellulose surface. 相似文献
315.
Kaur K Jain M Khan SI Jacob MR Tekwani BL Singh S Singh PP Jain R 《Bioorganic & medicinal chemistry》2011,19(1):197-210
In continuing our search of potent antimalarials based on 8-aminoquinoline structural framework, three series of novel bis(8-aminoquinolines) using convenient one to four steps synthetic procedures were synthesized. The bisquinolines were evaluated for in vitro antimalarial (Plasmodiumfalciparum), antileishmanial (Leishmaniadonovani), antimicrobial (a panel of pathogenic bacteria and fungi), cytotoxicity, ??-hematin inhibitory and methemoglobin (MetHb) formation activities. Several compounds exhibited superior antimalarial activities compared to parent drug primaquine. Selected compounds (44, 61 and 79) when tested for in vivo blood-schizontocidal antimalarial activity (Plasmodiumberghei) displayed potent blood-schizontocial activities. The bisquinolines showed negligible MetHb formation (0.2-1.2%) underlining their potential in the treatment of glucose-6-phosphate dehydrogenase deficient patients. The bisquinoline analogues (36, 73 and 79) also exhibited promising in vitro antileishmanial activity, and antimicrobial activities (43, 44 and 76) against a panel of pathogenic bacteria and fungi. The results of this study provide evidence that bis(8-aminoquinolines), like their bis(4-aminoquinolines) and artemisinin dimers counterparts, are a promising class of antimalarial agents. 相似文献
316.
Sequence data of mitochondrial cytochrome b gene and nuclear ITS2 region were used to assess genetic diversity, intraspecific phylogeography and population genetic structure of the oak gall wasp Andricus chodjaii from Turkey. We examined 293 individuals from 21 localities which generated 57 cyt b haplotypes and 8 ITS2 alleles. The average genetic diversity was 0.575 for cyt b and 0.202 ITS2, and the average nucleotide diversity 0.015 for cyt b gene and 0.001 for the ITS2 region. Phylogenetic analyses of cyt b haplotypes produced mostly similar topologies with geographically significant groupings. The ITS2 data provided less resolution without robust and apparent geographic structure. Population demographic analysis indicated that some eastern populations expanded, however, some others underwent either expansion or decline resulting in genetically structured populations. Molecular clock applied to the mtDNA data indicated that ingroup haplotypes diversified from the outgroup haplotypes around Early Pliocene. Further diversification events throughout Pleistocene resulted in major clade formations. It appears that geographic formations and glacial and interglacial cycles of Pleistocene were crucial for shaping the phylogeographic structure of A. chodjaii in Turkey. 相似文献
317.
Nafees U. Din Obioha C. Ukoumunne Greg Rubin William Hamilton Ben Carter Sal Stapley Richard D. Neal 《PloS one》2015,10(5)
BackgroundTime from symptomatic presentation to cancer diagnosis (diagnostic interval) is an important, and modifiable, part of the patient’s cancer pathway, and can be affected by various factors such as age, gender and type of presenting symptoms. The aim of this study was to quantify the relationships of diagnostic interval with these variables in 15 cancers diagnosed between 2007 and 2010 using routinely collected data from the Clinical Practice Research Datalink (CPRD) in the UK.MethodsSymptom lists for each cancer were prepared from the literature and by consensus amongst the clinician researchers, which were then categorised into either NICE qualifying (NICE) or not (non-NICE) based on NICE Urgent Referral Guidelines for Suspected Cancer criteria. Multivariable linear regression models were fitted to examine the relationship between diagnostic interval (outcome) and the predictors: age, gender and symptom type.Results18,618 newly diagnosed cancer patients aged ≥40 who had a recorded symptom in the preceding year were included in the analysis. Mean diagnostic interval was greater for older patients in four disease sites (difference in days per 10 year increase in age; 95% CI): bladder (10.3; 5.5 to 15.1; P<0.001), kidney (11.0; 3.4 to 18.6; P=0.004), leukaemia (18.5; 8.8 to 28.1; P<0.001) and lung (10.1; 6.7 to 13.4; P<0.001). There was also evidence of longer diagnostic interval in older patients with colorectal cancer (P<0.001). However, we found that mean diagnostic interval was shorter with increasing age in two cancers: gastric (-5.9; -11.7 to -0.2; P=0.04) and pancreatic (-6.0; -11.2 to -0.7; P=0.03). Diagnostic interval was longer for females in six of the gender non-specific cancers (mean difference in days; 95% CI): bladder (12.2; 0.8 to 23.6; P=0.04), colorectal (10.4; 4.3 to 16.5; P=0.001), gastric (14.3; 1.1 to 27.6; P=0.03), head and neck (31.3; 6.2 to 56.5; P=0.02), lung (8.0; 1.2 to 14.9; P=0.02), and lymphoma (19.2; 3.8 to 34.7; P=0.01). Evidence of longer diagnostic interval was found for patients presenting with non-NICE symptoms in 10 of 15 cancers (mean difference in days; 95% CI): bladder (62.9; 48.7 to 77.2; P<0.001), breast (115.1; 105.9 to 124.3; P<0.001), cervical (60.3; 31.6 to 89.0; P<0.001), colorectal (25.8; 19.6 to 31.9; P<0.001), gastric (24.1; 3.4 to 44.8; P=0.02), kidney (22.1; 4.5 to 39.7; P=0.01), oesophageal (67.0; 42.1 to 92.0; P<0.001), pancreatic (48.6; 28.1 to 69.1; P<0.001), testicular (36.7; 17.0 to 56.4; P< 0.001), and endometrial (73.8; 60.3 to 87.3; P<0.001). Pooled analysis across all cancers demonstrated highly significant evidence of differences overall showing longer diagnostic intervals with increasing age (7.8 days; 6.4 to 9.1; P<0.001); for females (8.9 days; 5.5 to 12.2; P<0.001); and in non-NICE symptoms (27.7 days; 23.9 to 31.5; P<0.001).ConclusionsWe found age and gender-specific inequalities in time to diagnosis for some but not all cancer sites studied. Whilst these need further explanation, these findings can inform the development and evaluation of interventions intended to achieve timely diagnosis and improved cancer outcomes, such as to provide equity across all age and gender groupings. 相似文献
318.
Muqader Shah Hafsa Zaneb Saima Masood Rifat Ullah Khan Muhammad Mobashar Imad Khan Salahud Din Muhammad Shoaib Khan Habib Ur Rehman Antonella Tinelli 《Probiotics and antimicrobial proteins》2020,12(2):473-480
Two-hundred-eighty-day-old broiler chicks were divided into seven groups. The groups were designated as T1, thermoneutral zone; T2, heat stressed (HS); T3, 相似文献
319.
320.
High-fluoride (100 and 200?ppm) water was administered to rats orally to study the fluoride-induced changes on the thyroid hormone status, the histopathology of discrete brain regions, the acetylcholine esterase activity, and the learning and memory abilities in multigeneration rats. Significant decrease in the serum-free thyroxine (FT4) and free triiodothyronine (FT3) levels and decrease in acetylcholine esterase activity in fluoride-treated group were observed. Presence of eosinophilic Purkinje cells, degenerating neurons, decreased granular cells, and vacuolations were noted in discrete brain regions of the fluoride-treated group. In the T-maze experiments, the fluoride-treated group showed poor acquisition and retention and higher latency when compared with the control. The alterations were more profound in the third generation when compared with the first- and second-generation fluoride-treated group. Changes in the thyroid hormone levels in the present study might have imbalanced the oxidant/antioxidant system, which further led to a reduction in learning memory ability. Hence, presence of generational or cumulative effects of fluoride on the development of the offspring when it is ingested continuously through multiple generations is evident from the present study. 相似文献