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排序方式: 共有432条查询结果,搜索用时 28 毫秒
1.
Bardet–Biedl Syndrome is a multisystem autosomal recessive disorder characterized by central obesity, polydactyly, hypogonadism, learning difficulties, rod-cone dystrophy and renal dysplasia. Bardet–Biedl Syndrome has a prevalence rate ranging from 1 in 100,000 to 1 in 160,000 births although there are communities where Bardet–Biedl Syndrome is found at a higher frequency due to consanguinity. We report here a Pakistani consanguineous family with two affected sons with typical clinical features of Bardet–Biedl Syndrome, in addition to abnormal liver functioning and bilateral basal ganglia calcification, the latter feature being typical of Fahr's disease. Homozygous regions obtained from SNP array depicted three known genes BBS10, BBS14 and BBS2. Bidirectional sequencing of all coding exons by traditional sequencing of all these three genes showed a homozygous deletion of 10 nucleotides (c.1958_1967del), in BBS10 in both affected brothers. The segregation analysis revealed that the parents, paternal grandfather, maternal grandmother and an unaffected sister were heterozygous for the deletion. Such a large deletion in BBS10 has not been reported previously in any population and is likely to be contributing to the phenotype of Bardet–Biedl Syndrome in this family. 相似文献
2.
Akram Najafi Mojtaba Hasanpour Azam Askary Masoud Aziemzadeh Najmeh Hashemi 《Folia microbiologica》2018,63(3):335-343
The present study was aimed at investigating the relationship between the new Clermont’s phylogenetic groups, virulence factors, and pathogenicity island markers (PAIs) among uropathogenic Escherichia coli (UPEC) in Iran. This cross-sectional study was carried out on 140 UPEC isolates collected from patients with urinary tract infections in Bushehr, Iran. All isolates were subjected to phylogenetic typing using a new quadruplex-PCR method. The presence of PAI markers and virulence factors in UPEC strains was evaluated by multiplex PCR. The most predominant virulence gene was fimH (85%), followed by iucC (61.4%), papC (38.6%), hlyA (22.1%), cnf-1 (18.6%), afa (10.7%), papG and neuC (each 9.3%), ibeA (3.6%), and sfa/foc (0.7%). The most common phylogenetic group was related to B2 (39.3%), and the least common to A (0.7%). The most prevalent PAI marker was PAI IV536 (77.14%), while markers for PAI III536 (13.57%), PAI IIJ96 (12.86%), and PAI II536 (12.14%) were the least frequent among the UPEC strains. Meanwhile, the PAI IJ96 marker was not detected. There was a significant association between the phylogenetic group B2 and all the studied virulence genes and PAI markers. To our knowledge, this is the first study to compare the relationship between new phylogenetic groups, virulence genes and PAI markers in UPEC strains in Iran. The phylogenetic group B2 was predominantly represented among the studied virulence genes and PAI markers, indicating the preference of particular strains to carry virulence genes. 相似文献
3.
Asadullah Azam Yasuhisa Kunimi Maki N. Inoue Madoka Nakai 《Applied Entomology and Zoology》2016,51(3):479-488
4.
Noushin Saljoughian Tahereh Taheri Farnaz Zahedifard Yasaman Taslimi Fatemeh Doustdari Azam Bolhassani Delaram Doroud Hiva Azizi Kazem Heidari Mohammad Vasei Nabiollah Namvar Asl Barbara Papadopoulou Sima Rafati 《PLoS neglected tropical diseases》2013,7(4)
Visceral leishmaniasis (VL) is a vector-borne disease affecting humans and domestic animals that constitutes a serious public health problem in many countries. Although many antigens have been examined so far as protein- or DNA-based vaccines, none of them conferred complete long-term protection. The use of the lizard non-pathogenic to humans Leishmania (L.) tarentolae species as a live vaccine vector to deliver specific Leishmania antigens is a recent approach that needs to be explored further. In this study, we evaluated the effectiveness of live vaccination in protecting BALB/c mice against L. infantum infection using prime-boost regimens, namely Live/Live and DNA/Live. As a live vaccine, we used recombinant L. tarentolae expressing the L. donovani A2 antigen along with cysteine proteinases (CPA and CPB without its unusual C-terminal extension (CPB-CTE)) as a tri-fusion gene. For DNA priming, the tri-fusion gene was encoded in pcDNA formulated with cationic solid lipid nanoparticles (cSLN) acting as an adjuvant. At different time points post-challenge, parasite burden and histopathological changes as well as humoral and cellular immune responses were assessed. Our results showed that immunization with both prime-boost A2-CPA-CPB-CTE-recombinant L. tarentolae protects BALB/c mice against L. infantum challenge. This protective immunity is associated with a Th1-type immune response due to high levels of IFN-γ production prior and after challenge and with lower levels of IL-10 production after challenge, leading to a significantly higher IFN-γ/IL-10 ratio compared to the control groups. Moreover, this immunization elicited high IgG1 and IgG2a humoral immune responses. Protection in mice was also correlated with a high nitric oxide production and low parasite burden. Altogether, these results indicate the promise of the A2-CPA-CPB-CTE-recombinant L. tarentolae as a safe live vaccine candidate against VL. 相似文献
5.
F. Azam 《Plant and Soil》1990,125(2):255-262
A pot experiment was conducted to study the effect of organic and inorganic nitrogen (N) sources on the yield and N uptake
of rice from applied and native soil-N. The residual effect of these N sources on a succeeding wheat crop was also studied.
Organic N was applied in the form of 15N-labelled Sesbania aculeata L., a legume, and inorganic N in the form of 15N-labelled ammonium sulphate. The two sources were applied to the soil separately or together at the time of transplanting
rice.
Recovery of N by rice from both the applied sources was quite low but both sources caused significant increases in biomass
and N yield of rice. Maximum increase was recorded in soil treated with organic N. The residual value of the two materials
as source of N for wheat was not significant; the wheat took up only a small fraction of the N initially applied. Loss of
N occurred from both applied N sources, the losses being more from inorganic N.
Both applied N sources caused a substantial increase in the availability of soil-N to rice and wheat; most of this increase
was due to organic N and was attributed to the so-called ‘priming’ effect or ANI (added nitrogen interaction) of the applied
material. 相似文献
6.
Mahboudi Somayeh Moosavi-Nasab Marzieh Kazemi Bahram Rahimpour Azam Eskandari Mohammad Hadi Mohammadian Omid Shams Forough 《Molecular biology reports》2021,48(5):4405-4412
Molecular Biology Reports - Monoclonal antibodies (mAbs) are widely employed as invaluable therapeutics for a vast number of human disorders. Several approaches have been introduced for the... 相似文献
7.
Azam Sadat Hosseini Alhashemi Abdolreza R. Karbassi Bahram Hassanzadeh Kiabi Seyed Masoud Monavari Seyed Mohammad Bagher Nabavi Mohammad Sadegh Sekhavatjou 《Biological trace element research》2011,142(3):500-516
Present study investigates relationships between total and bioaccessibility of trace elements (Cd, Co, Cr, Cu, Mn, NI, Pb,
V, and Zn) concentrations in sediment and their bioaccumulation in species in Shadegan wetland in southwest of Iran. Bioavailability
factor (BAF) and translocation factor (TF) were calculated in plants and trophic transfer factor (TTF) was determined in bird
species. For this purpose, sampling of sediments, aquatic plants including Phragmites australis, Typha australis, Scripus maritimus and two bird species encircling Porphyrio porphyrio and globally threatened Marmaronetta angustirostris were carried out during winter 2009. Result of chemical analysis show that bioaccessibility concentrations of Mn (8.31 mg/kg),
V (1.33 mg/kg), and Pb (1.03 mg/kg) are higher than other metals. The uptake trend of trace elements in plant decreases as
root > stem > leaf. Accumulation levels of trace elements in different tissues of P. porphyrio and M. angustirostris are almost identical and considerable. Accumulation and toxicity of Cd in birds is more than plants. In addition, BAF of
V, Pb, and Cr indicates high accumulation by plants and great pollution rate in the area of study. In S. maritimus TF for Mn, Cu, Pb, and V are high whereas in T. australis, Cu and Pb posses the highest TF. Also Cr, Co, Mn, Ni, and Zn have higher TF from stem to leaf than root to stem in P. australis. Finally, TTFs were compared in various bird species. 相似文献
8.
Ana Beloqui Taras Y. Nechitaylo Nieves López-Cortés Azam Ghazi María-Eugenia Guazzaroni Julio Polaina Axel W. Strittmatter Oleg Reva Agnes Waliczek Michail M. Yakimov Olga V. Golyshina Manuel Ferrer Peter N. Golyshin 《Applied and environmental microbiology》2010,76(17):5934-5946
The guts and casts of earthworms contain microbial assemblages that process large amounts of organic polymeric substrates from plant litter and soil; however, the enzymatic potential of these microbial communities remains largely unexplored. In the present work, we retrieved carbohydrate-modifying enzymes through the activity screening of metagenomic fosmid libraries from cellulose-depleting microbial communities established with the fresh casts of two earthworm species, Aporrectodea caliginosa and Lumbricus terrestris, as inocula. Eight glycosyl hydrolases (GHs) from the A. caliginosa-derived community were multidomain endo-β-glucanases, β-glucosidases, β-cellobiohydrolases, β-galactosidase, and β-xylosidases of known GH families. In contrast, two GHs derived from the L. terrestris microbiome had no similarity to any known GHs and represented two novel families of β-galactosidases/α-arabinopyranosidases. Members of these families were annotated in public databases as conserved hypothetical proteins, with one being structurally related to isomerases/dehydratases. This study provides insight into their biochemistry, domain structures, and active-site architecture. The two communities were similar in bacterial composition but significantly different with regard to their eukaryotic inhabitants. Further sequence analysis of fosmids and plasmids bearing the GH-encoding genes, along with oligonucleotide usage pattern analysis, suggested that those apparently originated from Gammaproteobacteria (pseudomonads and Cellvibrio-like organisms), Betaproteobacteria (Comamonadaceae), and Alphaproteobacteria (Rhizobiales).Microorganisms producing diverse glycosyl hydrolases (GHs) are widespread and typically thrive in environments where plant materials tend to accumulate and deteriorate (42, 73). The habitats of microorganisms with great GH diversity are the ruminant animal rumen, mouse bowel, and rabbit cecum (10, 24, 26, 28, 49, 74). Microorganisms associated with soil invertebrates in general and with soil earthworms in particular carry out metabolic processes that contribute to element cycling and are essential in sustaining processes which their hosts are unable to perform (20, 52, 72, 76). Although some species of earthworms produce cellulases (15, 55), they generally rely on microbes inhabiting their gastrointestinal (GI) tracts to perform cellulose utilization processes (31, 47, 77). Casts are of special interest in this respect. Considering that the overall numbers of cellulolytic microbes in earthworm casts are greater than those in soil (57), earthworm casts seem to play an important role in the decomposition of plant litter, serving as an inoculum for cellulosic substrates (9). It is important to note that microorganisms from preingested substratum (soil or plant litter) are predominant in the gut lumen (20); however, microbial populations in earthworm casts differ from those in soil in terms of diversity and the relative abundance of different taxa (29, 57, 63). It is anticipated that the enzymatic repertoire of such microbial communities must be especially broad toward diverse sugar-based polymeric, oligomeric, and monomeric substrates; however, among approximately 115 families of GHs with thousands of members known to date (12), none of the GHs have been derived from microorganisms of earthworm-associated microbial communities.The aim of the present work was therefore to examine the diversity of GHs in metagenome libraries derived from fresh casts of Aporrectodea caliginosa and Lumbricus terrestris earthworms via functional screening. Other important tasks of this work were to characterize individual enzymes and to gain insight into their structural-functional features. Finally, we performed sequence analysis of large contiguous DNA fragments of fosmids harboring the genes for GHs to associate them with the organism(s) that may produce them, which was complemented by conventional small-subunit (SSU) rRNA clone library sequencing analysis. 相似文献
9.
Binyamin R Aslam Khan M Khan AI Azam Khan M Awan FS Khan NA 《Genetics and molecular research : GMR》2011,10(3):1681-1688
Urdbean (Vigna mungo) is an important pulse crop grown worldwide. Urdbean leaf crinkle virus (ULCV) is a pathogen of urdbean found in Pakistan that causes huge losses in yield. Forty urdbean varieties/lines were screened against the virus under field conditions during spring season 2009. None of the lines appeared to be highly resistant or resistant. On the basis of a 0-5 disease rating scale and disease severity index, genotypes varied significantly in their reaction to ULCV. Four lines (M-6206, IAM-382-15, IAM-133, and Mash-1) were moderately resistant, eight were rated as moderately susceptible, and 21 as susceptible; the remaining seven lines were highly susceptible. RAPD analyses revealed an extensive amount of variation, which could be used for cultivar identification. Genetic differentiation among urdbean genotypes was similar to the field screening data. The varieties 6065-3 and 6206 were highly susceptible and moderately resistant, respectively, to ULCV under field conditions, confirmed by the RAPD analysis. These varieties were the most diverse varieties in the similarity matrix (67.2%), while the varieties IAM-382-9 and 07M003 were the most similar (98.4%). This information will help in the recognition of available resistant germplasms that can resist this disease and will be utilized for urdbean improvement in Pakistan. 相似文献
10.
The mechanism of d-glucose transport in the marine bacterium Serratia marinorubra was investigated. Uptake is mediated by a single, constitutive phosphoenolpyruvate:sugar phosphotransferase system (PTS), resulting in phosphorylation of d-glucose to d-glucose phosphate during transport. The system is saturable (K(m) = 6.4 x 10 M) and highly temperature dependent, with a Q(10) of 3.5 between 5 and 15 degrees C. The system is highly specific for d-glucose; structurally related sugars and sugar alcohols did not significantly compete with d-glucose for transport. The PTS requires Mg (K(m) = 2.5 x 10 M), but its activity is otherwise unaffected by salinity changes over the range tested (0 to 35 per thousand). S. marinorubra differs from other gram-negative organisms (Escherichia coli and Salmonella typhimurium) in that its glycerol (non-PTS substrate) permease is not regulated by the presence of glucose (PTS substrate). 相似文献