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1.
The genetically modified cotton holding Bt proteins, is noxious to bollworms larvae but very little is known about its impact on population of non-target spiders within the field. Studies conducted with the aim to identify spiders along with their abundance, prevalence pattern, preying habit on insect pests in Bt cotton (L280, Cry2Ab4) and commonness of symbiotic bacteria in these spiders. Spiders collections were made via vial tapping/jarring, from May to end of October (2018). In total, 13,342 spiders were recorded during the entire cropping season. Least relative abundance was in May (0.28%), highest in August (30.39%) while ahead decline was observed, reached to 12% in October. The 27 species were verified, least richness was in May (3 species), high in August (19 species), later in the end, reduced to 7 species. High abundance was of Hylyphantes graminicola (68.56%) and Neoscona theisi (19.98%). Existence of H. graminicola and Pardosa astrigera observed during the whole cropping season. Presence of seven guilds among spiders had a diverse nature of hunting insect pests and on number of species existed in the crop, maximum was from direct hunting habit. Composition and community structure of microbiota varied as of spider species. Proteobacteria was the most abundant bacterial phylum and topmost genus was Wolbachia in observed spiders. Five groups of bacteria distinguished across 4 clusters of spiders depending on core community of symbiotic bacterial genera. This effort is an initial step to get knowhow about spiders in Bt cotton, which will facilitate future research studies concerning spiders.  相似文献   
2.
Vegetation analysis provides the prerequisites to understand the overall community structure and function of any ecosystem and is a fundamental requirement for the precise evaluation of biodiversity. Although many studies have assessed floristic attributes of specific areas, there are still unexplored regions, as is the case of the mountain region in the Kashmir Himalayas. Current research highlighted the recent findings of the scientific characterization of floristic and ecological aspects on the forest flora found in the Bhimber hills, Pakistan. Floristically, a total of 93 species belonging to 80 genera in 41 families were recorded. The species distribution patterns across the families were disproportionate with half of the species contributed by 8 families and 25 families were monotypic. Based on the floristic analysis, Asteraceae was the largest family with 12% of species followed by Poaceae with (11%) species. PAST software, a multivariate ecological community analysis was used to classify the species similarities and differences among the different habitat types. According to the habitat wise distribution, 21% of species were growing in the natural forest habitat, while 15% of species were dispersed in highly distributed habitats along roadsides and 8% on pedestrians. In terms of functional diversity, the herbaceous growth form was dominant (58%). The biological spectrum revealed therophytes as the dominant life form as it indicates the disturbed habitat vegetation. The phytogeographical analysis revealed that the maximum (69%) species were native, while the minimum (31%) species were exotic. Thus, the study of these functional and habitat diversity patterns can significantly improve our understanding of the ecological aspects of the flora in the geographical location. This information may additionally be useful in devising management plans to ensure sustainable utilization and better management of forest landscapes in this Himalayan region.  相似文献   
3.
Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory tract infections in young children, but very little is known about its epidemiology and circulating genotypes in Pakistan. This study analyzed the epidemiological and molecular characteristics of RSV genotypes detected in Pakistani children less than 2 years of age with acute respiratory tract infections (ARIs) in a tertiary care hospital in Gilgit Baltistan (GB) province during 2011-12 winter season. RSV was detected in 75 out of 105 children presenting with acute respiratory infection. Male infants between 2-6 months age made up the highest percentage of RSV positive cases. Epidemiological factors such as pre-maturity, mean weight, clinical features and diagnosis when compared between RSV positive and negative groups were found to be statistically insignificant. Phylogenetic analysis classified all 75 of the RSV strains into 71 strains of subgroups A and 4 strains of subgroup B, respectively. Strains belonging to subgroups A and B were further subdivided into NA1/GA2 and BA, respectively. The nucleotide and deduced amino acid sequence identities were relatively high among these strains (>90%). Both RSV-A and RSV-B isolates had two potential N-glycosylation sites in HVR2 of G protein and with heavy O-glycosylation of serine and threonine residues (G scores of 0.5-0.7). This report highlights the significance of RSV as a dominant viral etiologic agent of pediatric ARIs, and need for continued molecular epidemiological surveys for early detection of prevalent strains and newly emerging genotypes to understand epidemiology of RSV infections in various regions of Pakistan.  相似文献   
4.
This work describes analyses of the function of the murid herpesvirus 4 strain 68 (MHV-68) M2 gene. A frameshift mutation was made in the M2 open reading frame that caused premature termination of translation of M2 after amino acid residue 90. The M2 mutant showed no defect in productive replication in vitro or in lungs after infection of mice. Likewise, the characteristic transient increase in spleen cell number, Vbeta4 T-cell-receptor-positive CD8(+) T-cell mononucleosis, and establishment of latency were unaffected. However, the M2 mutant virus was defective in its ability to cause the transient sharp rise in latently infected cells normally seen in the spleen after infection of mice. We also demonstrate that expression of M2 is restricted to B cells in the spleen and that M2 encodes a 30-kDa protein localizing predominantly in the cytoplasm and plasma membrane of B cells.  相似文献   
5.

Background

In early 2009, a novel influenza A(H1N1) virus that emerged in Mexico and United States rapidly disseminated worldwide. The spread of this virus caused considerable morbidity with over 18000 recorded deaths. The new virus was found to be a reassortant containing gene segments from human, avian and swine influenza viruses.

Methods/Results

The first case of human infection with A(H1N1)pdm09 in Pakistan was detected on 18th June 2009. Since then, 262 laboratory-confirmed cases have been detected during various outbreaks with 29 deaths (as of 31st August 2010). The peak of the epidemic was observed in December with over 51% of total respiratory cases positive for influenza. Representative isolates from Pakistan viruses were sequenced and analyzed antigenically. Sequence analysis of genes coding for surface glycoproteins HA and NA showed high degree of high levels of sequence identity with corresponding genes of regional viruses circulating South East Asia. All tested viruses were sensitive to Oseltamivir in the Neuraminidase Inhibition assays.

Conclusions

Influenza A(H1N1)pdm09 viruses from Pakistan form a homogenous group of viruses. Their HA genes belong to clade 7 and show antigenic profile similar to the vaccine strain A/California/07/2009. These isolates do not show any amino acid changes indicative of high pathogenicity and virulence. It is imperative to continue monitoring of these viruses for identification of potential variants of high virulence or drug resistance.  相似文献   
6.
The viral metagenome within an activated sludge microbial assemblage was sampled using culture-dependent and culture-independent methods and compared to the diversity of activated sludge bacterial taxa. A total of 70 unique cultured bacterial isolates, 24 cultured bacteriophages, 829 bacterial metagenomic clones of 16S rRNA genes, and 1,161 viral metagenomic clones were subjected to a phylogenetic analysis.Bacteriophages play an active role in the ecology of natural environments, influencing prokaryotic population dynamics (5, 15) and mediating lateral gene transfer between diverse bacterial species, for example. Activated sludge (AS) microbial assemblages in wastewater treatment plants have been shown to harbor great numbers of viruses with a wide range of genome sizes (7, 9, 10, 16). Historically, the focus of wastewater viral studies has been on specific host-virus interactions, the application of phages as tools in microbial source tracking, or the use of phages to improve the efficiency of the wastewater treatment process (e.g., foam and pathogen control) (2, 4, 8, 12, 17). Despite the interest in the wastewater viral community, a census of the activated sludge total viral community has not, to our knowledge, been investigated using both culture-based and metagenomic approaches.  相似文献   
7.
8.
Addition of hydroxylamine (NH2OH) to autotrophic biomass in nitrifying bioreactors affected the activity, physical structure, and microbial ecology of nitrifying aggregates. When NH2OH is added to nitrifying cultures in 6-h batch experiments, the initial NH3-N uptake rates were physiologically accelerated by a factor of 1.4-13. NH2OH addition caused a 20-40% decrease in the median aggregate size, broadened the shape of the aggregate size distribution by up to 230%, and caused some of the microcolonies to appear slightly more dispersed. Longer term NH2OH addition in fed batch bioreactors decreased the median aggregate size, broadened the aggregate size distribution, and decreased NH3-N removal from >90% to values ranging between 75% and 17%. This altered performance is explained by quantitative fluorescence in situ hybridization (FISH) results that show inhibition of nitrifying populations, and by qPCR results showing that the copy numbers of amoA and nxrA genes gradually decreased by up to an order-of-magnitude. Longer term NH2OH addition damaged the active biomass. This research clarifies the effect of NH2OH on nitrification and demonstrates the need to incorporate NH2OH-related dynamics of the nitrifying biomass into mathematical models, accounting for both ecophysiological and structural responses.  相似文献   
9.
This study is the first to report on vascular effect of the chromogranin A derived Vasostatin-I (CgA(1-76)) in vivo. Cardiovascular parameters were recorded in 29 rabbits with sympathetically decentralized right carotid vascular bed. The recombinant human STA CgA(1-78) (VS-1) was infused at 480 μg/kg over 25 min. Group I was kept awake while groups II-V were anesthetized with Ketamine-xylazine. VS-1 was given alone in groups I-II while in presence of either phentolamine, phentolamine plus propranolol or hexamethonium in groups III-V. Serum VS-1 peaked at 2 μg/ml (200 nM) before onset of vascular effects and declined rapidly to ~200 ng/ml within 30 min. In all groups but III and IV VS-1 induced a brief vasoconstriction, being larger in intact than in sympathetically decentralized beds. The VS-1 induced vasoconstriction was not altered by hexamethonium but was abolished by phentolamine. In presence of the α-adrenergic blocker a long lasting vasodilatation, unaffected by propranolol, was apparent on both innervated and decentralized sides. In conclusion, VS-1 induced an α-adrenoceptor-mediated vasoconstriction presumably brought about by noradrenaline release from sympathetic nerves when infused at a dose giving an initial serum concentration of ~200 nM. This initial vasoconstriction masked a persistent adrenoceptor-independent vasodilatation, consistent with previous reports from in vitro models.  相似文献   
10.
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