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121.
Nazish Badar Uzma Bashir Aamir Muhammad Rashid Mehmood Nadia Nisar Muhammad Masroor Alam Birjees Mazhar Kazi Syed Sohail Zahoor Zaidi 《PloS one》2013,8(11)
Background
There is little information about influenza among the Pakistani population. In order to assess the trends of Influenza-like-Illness (ILI) and to monitor the predominant circulating strains of influenza viruses, a country-wide lab-based surveillance system for ILI and Severe Acute Respiratory Illness (SARI) with weekly sampling and reporting was established in 2008. This system was necessary for early detection of emerging novel influenza subtypes and timely response for influenza prevention and control.Methods
Five sentinel sites at tertiary care hospitals across Pakistan collected epidemiological data and respiratory samples from Influenza-like illness (ILI) and severe acute respiratory illness (SARI) cases from January 2008 to December 2011. Samples were typed and sub-typed by Real-Time RT-PCR assay.Results
A total of 6258 specimens were analyzed; influenza virus was detected in 1489 (24%) samples, including 1066 (72%) Influenza type A and 423 (28%) influenza type B viruses. Amongst influenza A viruses, 25 (2%) were seasonal A/H1N1, 169 (16%) were A/H3N2 and 872 (82 %) were A(H1N1)pdm09. Influenza B virus circulation was detected throughout the year along with few cases of seasonal A/H1N1 virus during late winter and spring. Influenza A/H3N2 virus circulation was mainly observed during summer months (August-October).Conclusions
The findings of this study emphasize the need for continuous and comprehensive influenza surveillance. Prospective data from multiple years is needed to predict seasonal trends for vaccine development and to further fortify pandemic preparedness. 相似文献122.
Youssif M. Ali Hany I. Kenawy Adnan Muhammad Robert B. Sim Peter W. Andrew Wilhelm J. Schwaeble 《PloS one》2013,8(12)
The complement system is an essential component of the immune response, providing a critical line of defense against different pathogens including S. pneumoniae. Complement is activated via three distinct pathways: the classical (CP), the alternative (AP) and the lectin pathway (LP). The role of Pneumolysin (PLY), a bacterial toxin released by S. pneumoniae, in triggering complement activation has been studied in vitro. Our results demonstrate that in both human and mouse sera complement was activated via the CP, initiated by direct binding of even non-specific IgM and IgG3 to PLY. Absence of CP activity in C1q−/− mouse serum completely abolished any C3 deposition. However, C1q depleted human serum strongly opsonized PLY through abundant deposition of C3 activation products, indicating that the LP may have a vital role in activating the human complement system on PLY. We identified that human L-ficolin is the critical LP recognition molecule that drives LP activation on PLY, while all of the murine LP recognition components fail to bind and activate complement on PLY. This work elucidates the detailed interactions between PLY and complement and shows for the first time a specific role of the LP in PLY-mediated complement activation in human serum. 相似文献
123.
A new species of Lepiota, L. vellingana, is described and illustrated from Lahore, Pakistan. It is characterized by a campanulate to plano-convex, slightly umbonate, white pileus covered with pinkish brown scales, crowded lamellae, guttulate basidiospores, long trichodermial stipe elements, and long trichodermial pileal elements. 相似文献
124.
Umbreen Shahzad M. Awais Khan Muhammad Jaffar Jaskani Iqrar Ahmad Khan Schuyler S. Korban 《Conservation Genetics》2013,14(6):1161-1172
Moringa is a genus of the tropical flowering plant family Moringaceae containing 13 diverse species. Among the different species, only Moringa oleifera L. is cultivated. This species has great potential in serving as a high-value crop for food, medicinal products, as well as fodder for animals, particularly in developing tropical regions of the world. In this study, the genetic diversity and population structure of world-wide collections of M. oleifera were investigated using DNA markers. A total of 19 microsatellite or simple sequence repeat (SSR) markers along with a partial sequence of the chloroplast gene atpB were used to study genetic diversity within 161 accessions of M. oleifera collected from Asia, Africa, North and South America, and the Caribbean. On average, 8.3 alleles/per SSR were amplified in each accession. A total number of 158 alleles were detected in 131 accessions collected from the wild in Pakistan and from 30 accessions obtained from ECHO (Florida). Observed heterozygosity varied from 0.16 to 0.86, with an average of 0.58, while the average PIC value was 0.59. Partial sequencing of chloroplast genes of 43 of 161 plants generated mixed patterns. These findings have demonstrated that there is a large genetic diversity present in wild collections of M. oleifera collected in Pakistan; whereas low genetic diversity is detected in cultivated accessions obtained from ECHO. Taken together, these results agree with previous reports that M. oleifera is native to the Indo-Pakistan ecological region, and provides sufficient diversity for genetic exploration as well as for genetic improvement efforts. 相似文献
125.
Qurra-tul-Ann Afza Gardner Hooria Younas Muhammad Akhtar 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(1):182-190
Human M-proinsulin was cleaved by trypsin at the R31R32–E33 and K64R65–G66 bonds (B/C and C/A junctions), showing the same cleavage specificity as exhibited by prohormone convertases 1 and 2 respectively. Buffalo/bovine M-proinsulin was also cleaved by trypsin at the K59R60–G61 bond but at the B/C junction cleavage occurred at the R31R32–E33 as well as the R31–R32E33 bond. Thus, the human isoform in the native state, with a 31 residue connecting C-peptide, seems to have a unique structure around the B/C and C/A junctions and cleavage at these sites is predominantly governed by the structure of the proinsulin itself. In the case of both the proinsulin species the cleavage at the B/C junction was preferred (65%) over that at the C/A junction (35%) supporting the earlier suggestion of the presence of some form of secondary structure at the C/A junction. Proinsulin and its derivatives, as natural substrates for trypsin, were used and mass spectrometric analysis showed that the kcat./Km values for the cleavage were most favourable for the scission of the bonds at the two junctions (1.02 ± 0.08 × 105 s− 1 M− 1) and the cleavage of the K29–T30 bond of M-insulin-RR (1.3 ± 0.07 × 105 s− 1 M− 1). However, the K29–T30 bond in M-insulin, insulin as well as M-proinsulin was shielded from attack by trypsin (kcat./Km values around 1000 s− 1 M− 1). Hence, as the biosynthetic path follows the sequence; proinsulin → insulin-RR → insulin, the K29–T30 bond becomes shielded, exposed then shielded again respectively. 相似文献
126.
Ghias Uddin Abdul Latif Mohammad Arfan Mumtaz Ali Syed Hamid Hussain Thomas J. Simpson Russel J. Cox Muhammad Iqbal Choudhary 《Phytochemistry letters》2013,6(1):84-89
Three new phenolic compounds, sorlanin (4-(3-(hydroxymethyl)-5-methoxy-7-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-2-yl)-2-methoxyphenol, 1), sorbanin (2-((3,5-dimethoxy-[1,1′-biphenyl]-4-yl)oxy)-1-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol, 2) and sorbalanin (4-(3-(hydroxymethyl)-5,6-dimethoxy-2,3-dihydrobenzo[b][1,4]dioxino[2,3-g]benzofuran-2-yl)-2-methoxyphenol, 3), together with eight known compounds, polystachyol (4), isolariciresinol (5), dihydrodehydrodiconiferyl alcohol (6), tuberculatin (7), ovafolinin E (8), aucuparin (9), 2′-methoxyaucuparin (10), and tetracosyl-3-(3,4-dihydroxyphenyl)acrylate (11), were isolated from Sorbus lanata. The structures of these phytoconstituents were elucidated through extensive spectroscopic techniques, including UV, IR, 1D and 2D NMR, ESI-MS and HRESI-MS experiments. All the compounds except 9 and 10 were isolated for the first time from the genus Sorbus. The isolated compounds were also tested in DPPH radical scavenging reaction where compounds 6, 7, 10 and 11 showed significant activities with IC50 values of 9.2, 11.7, 23.0 and 33.7 μM, respectively. 相似文献
127.
Uzma Bashir Aamir Muhammad Masroor Alam Hajra Sadia Syed Sohail Zahoor Zaidi Birjees Mazher Kazi 《PloS one》2013,8(9)
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
128.
Md. Mahmodul Hasan Sohel Michael Hoelker Sina Seifi Noferesti Dessie Salilew-Wondim Ernst Tholen Christian Looft Franca Rings Muhammad Jasim Uddin Thomas E. Spencer Karl Schellander Dawit Tesfaye 《PloS one》2013,8(11)
Cell-cell communication within the follicle involves many signaling molecules, and this process may be mediated by secretion and uptake of exosomes that contain several bioactive molecules including extra-cellular miRNAs. Follicular fluid and cells from individual follicles of cattle were grouped based on Brilliant Cresyl Blue (BCB) staining of the corresponding oocytes. Both Exoquick precipitation and differential ultracentrifugation were used to separate the exosome and non-exosomal fraction of follicular fluid. Following miRNA isolation from both fractions, the human miRCURY LNA™ Universal RT miRNA PCR array system was used to profile miRNA expression. This analysis found that miRNAs were present in both exosomal and non-exosomal fraction of bovine follicular fluid. We found 25 miRNAs differentially expressed (16 up and 9 down) in exosomes and 30 miRNAs differentially expressed (21 up and 9 down) in non-exosomal fraction of follicular fluid in comparison of BCB- versus BCB+ oocyte groups. Expression of selected miRNAs was detected in theca, granulosa and cumulus oocyte complex. To further explore the potential roles of these follicular fluid derived extra-cellular miRNAs, the potential target genes were predicted, and functional annotation and pathway analysis revealed most of these pathways are known regulators of follicular development and oocyte growth. In order to validate exosome mediated cell-cell communication within follicular microenvironment, we demonstrated uptake of exosomes and resulting increase of endogenous miRNA level and subsequent alteration of mRNA levels in follicular cells in vitro. This study demonstrates for the first time, the presence of exosome or non-exosome mediated transfer of miRNA in the bovine follicular fluid, and oocyte growth dependent variation in extra-cellular miRNA signatures in the follicular environment. 相似文献
129.
<i>Aspergillus tubingensis</i> Causes Leaf Spot of Cotton (<i>Gossypium hirsutum</i> L.) in Pakistan
Maria Khizar Urooj Haroon Musrat Ali Samiah Arif Iftikhar Hussain Shah Hassan Javed Chaudhary Muhammad Farooq Hussain Munis 《Phyton》2020,89(1):103-109
Cotton (Gossypium hirsutum L.) is a key fiber crop of great commercial
importance. Numerous phytopathogens decimate crop production by causing
various diseases. During July-August 2018, leaf spot symptoms were recurrently
observed on cotton leaves in Rahim Yar Khan, Pakistan and adjacent areas. Infected
leaf samples were collected and plated on potato dextrose agar (PDA) media.
Causal agent of cotton leaf spot was isolated, characterized and identified as
Aspergillus tubingensis based on morphological and microscopic observations.
Conclusive identification of pathogen was done on the comparative molecular
analysis of CaM and β-tubulin gene sequences. BLAST analysis of both sequenced
genes showed 99% similarity with A. tubingensis. Koch’s postulates were followed
to confirm the pathogenicity of the isolated fungus. Healthy plants were inoculated
with fungus and similar disease symptoms were observed. Fungus was re-isolated
and identified to be identical to the inoculated fungus. To our knowledge, this is the
first report describing the involvement of A. tubingensis in causing leaf spot disease
of cotton in Pakistan and around the world. 相似文献
130.
Shulin Tang Xu-Fang Liang Shan He Muhammad Shoaib Alam Haocan Luo Yulan Kuang 《Journal of fish biology》2020,97(6):1624-1631
Activin A belongs to the superfamily of transforming growth factor-β and plays an important role in hormone regulation and tissue development. However, few research studies have been conducted on the effect of activin A on feeding organs in fish. In this study, the zebrafish (Danio rerio) larvae were treated with 1 ng ml–1 activin A for 8 days continuously. The haematoxylin and eosin (H&E) staining section results revealed that the transverse inner diameter of the pharynx and oesophagus significantly increased on the third and eighth days after treatment compared with the control group (P < 0.05). On the eighth day, the cross-sectional area of the pharyngeal muscle increased by 8638 μm2 compared to the control group (P < 0.05). The RNA in situ hybridization results also showed that the expression of skeletal muscle-specific genes (myog and myod) was significantly increased in pharyngeal muscle on the eighth day. Furthermore, the qRT-PCR results showed the expression of gh gene was significantly increased on the eighth day (P < 0.05). At the same time, more larvae in activin A group were able to feed larger brine shrimp (Artemia) than in the control group on the eighth day. In conclusion, activin A could affect feeding by promoting the inner diameter and muscle development of the pharynx and oesophagus in zebrafish larvae. This study is the first to report that the development of the pharynx and oesophagus can directly affect food intake in fish larvae, which provides a theoretical basis for the study of food intake of fish at an early stage. 相似文献