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71.
72.
<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
73.
74.
Kamal Osama M. Shah Sayyed Hamad Ahmad Li Yan Hou Xilin Li Ying 《Molecular biology reports》2020,47(9):6887-6897
Molecular Biology Reports - The objective of the present work was the selection of cultivar, suitable medium and explant type for callus, root production, ascorbic acid, total ascorbic acid,... 相似文献
75.
Aman Shah Abdul Majid Amin Malik Shah Abdul Majid Zheng Qin Yin Dan Ji 《Neurochemical research》2013,38(7):1375-1393
Hydrogen sulphide (H2S) is one of three gaseous signaling molecules after nitric oxide and carbon monoxide. Various H2S donor compounds have been synthesized to study its physiological function. Among these compounds sodium hydrosulphide (NaHS), a donor of releasing H2S rapidly have shown to be protective in certain neuronal cell line but several in vivo studies have generated conflicting data. Furthermore several slow releasing H2S donors have been shown to have positive effects on cells in culture. The intracellular concentration of H2S and hence its rate of production may be a factor in keeping the balance between its neuroprotective and toxic effects. The present study was undertaken to deduce how a rapid releasing H2S donor (NaHS) as opposed to a slow releasing donor (ADTOH), affect oxidative stress related intracellular components and survival of RGC-5 cells. It was concluded that when RGC-5 cells are exposed to the toxic effects of glutamate in combination with buthionine sulfoxime (Glu/BSO), ADTOH was more efficacious in inhibiting apoptosis, scavenging reactive oxygen species (ROS), stimulation of glutathione (GSH) and gluthathione-S-transferase (GST). Western blot and qPCR analysis showed ADTOH increased the levels of Nrf2, HO-1, PKCα, p-Akt, Bcl-2 and XIAP but caused a decrease of Nfκβ and xCT greater than NaHS. This study is first to compare the efficacy of two H2S donor drugs as potential neuroprotectants and demonstrate that slow regulated release of H2S to cell culture can be more beneficial in inhibiting oxidative stress induced cell death. 相似文献
76.
Tara Kiran Alexander Kopp Rahim Moineddin J. Charles Victor Robert J. Campbell Baiju R. Shah Richard H. Glazier 《CMAJ》2013,185(3):E167-E173
Background:
Routine eye examinations for healthy adults aged 20–64 years were delisted from the Ontario Health Insurance Plan in 2004, but they continue to be insured for people with diabetes regardless of age. We sought to assess whether the delisting of routine eye examinations for healthy adults had the unintended consequence of decreasing retinopathy screening for adults with diabetes.Methods:
We used administrative data to calculate eye examinations for people with diabetes ages 40–64 years and 65 years and older in each 2-year period from 1998 to 2010. We examined differences by sex, income, rurality and type of health care provider. We used segmented linear regression to assess the change in trend before and after 2004.Results:
For people with diabetes aged 65 years and older, eye examinations rose gradually from 1998 to 2010, with no substantial change between 2004 and 2006. For people with diabetes aged 40–65 years, there was an 8.7% (95% confidence interval [CI] 6.3%–11.1%) decrease in eye examinations between 2004 and 2006. Results were similar for all population subgroups. Ophthalmologic examinations decreased steadily for both age groups during the study period, and there was a decline in optometry examinations for people ages 40–65 years after 2004.Interpretation:
The delisting of routine eye examinations for healthy adults in Ontario had the unintended consequence of reducing publicly funded retinopathy screening for people with diabetes. More research is needed to understand whether patients are being charged for an insured service or to what degree misunderstanding has prevented patients from seeking care.Diabetic retinopathy is the leading cause of new cases of blindness in people of working age.1 In the United States, about 40% of adults with diabetes aged 40 years and older have retinopathy, and 8% have vision-threatening retinopathy.2 Studies suggest that, if untreated, 50% of patients with proliferative diabetic retinopathy become legally blind within 5 years, compared with only 5% of patients who receive early treatment.3 Regular dilated eye examinations are effective for early detection and monitoring of asymptomatic retinopathy in people with diabetes4 and are recommended by clinical practice guidelines.5,6In Ontario, Canada’s most populous province, medically necessary services are covered by the Ontario Health Insurance Plan (OHIP) for all permanent residents and Canadian citizens living in the province.7 Under OHIP, routine eye examinations were fully insured for all children and adults until November 1, 2004. At that time, routine eye examinations ceased being insured for healthy adults aged 20–64 years, but continued to be insured for children aged 19 years and younger and for adults aged 65 years and older.8 Regardless of age, adults with diabetes and some other medical conditions affecting the eye, as well as adults receiving social assistance, continued to have an annual eye examination covered by OHIP. Insured examinations are at no cost to the patient and are reimbursed to the provider at about Can$40. In contrast, healthy adults aged 20–64 years are required to pay out-of-pocket or through private insurance for a routine eye examination, with fees set at the discretion of the optometrist9 or physician.10Health policy experts suggest that delisting services from insurance schemes can have unpredictable effects.11 Understanding the effect of delisting on care is particularly important as governments face fiscal pressures and contemplate further reductions in what is publicly insured.12 We sought to assess whether delisting routine eye examinations for healthy middle-aged adults in Ontario had the unintended consequence of decreasing retinopathy screening for middle-aged adults with diabetes, even though eye examinations continued to be insured for this population. 相似文献77.
Naman B. Shah Marcus L. Hutcheon Brian K. Haarer Thomas M. Duncan 《The Journal of biological chemistry》2013,288(13):9383-9395
F1-ATPase is the catalytic complex of rotary nanomotor ATP synthases. Bacterial ATP synthases can be autoinhibited by the C-terminal domain of subunit ϵ, which partially inserts into the enzyme''s central rotor cavity to block functional subunit rotation. Using a kinetic, optical assay of F1·ϵ binding and dissociation, we show that formation of the extended, inhibitory conformation of ϵ (ϵX) initiates after ATP hydrolysis at the catalytic dwell step. Prehydrolysis conditions prevent formation of the ϵX state, and post-hydrolysis conditions stabilize it. We also show that ϵ inhibition and ADP inhibition are distinct, competing processes that can follow the catalytic dwell. We show that the N-terminal domain of ϵ is responsible for initial binding to F1 and provides most of the binding energy. Without the C-terminal domain, partial inhibition by the ϵ N-terminal domain is due to enhanced ADP inhibition. The rapid effects of catalytic site ligands on conformational changes of F1-bound ϵ suggest dynamic conformational and rotational mobility in F1 that is paused near the catalytic dwell position. 相似文献
78.
Eric Hastie Dahlia M. Besmer Nirav R. Shah Andrea M. Murphy Megan Moerdyk-Schauwecker Carlos Molestina Lopamudra Das Roy Jennifer M. Curry Pinku Mukherjee Valery Z. Grdzelishvili 《Journal of virology》2013,87(18):10283-10294
Vesicular stomatitis virus (VSV) is a promising oncolytic agent against various malignancies. Here, for the first time, we tested VSV in vitro and in vivo in a clinically relevant, immunocompetent mouse model of pancreatic ductal adenocarcinoma (PDA). Our system allows the study of virotherapy against PDA in the context of overexpression (80% of PDA patients) or no expression of human mucin 1 (MUC1), a major marker for poor prognosis in patients. In vitro, we tested three VSV recombinants, wild-type VSV, VSV-green fluorescent protein (VSV-GFP), and a safe oncolytic VSV-ΔM51-GFP, against five mouse PDA cell lines that either expressed human MUC1 or were MUC1 null. All viruses demonstrated significant oncolytic abilities independent of MUC1 expression, although VSV-ΔM51-GFP was somewhat less effective in two PDA cell lines. In vivo administration of VSV-ΔM51-GFP resulted in significant reduction of tumor growth for tested mouse PDA xenografts (+MUC1 or MUC1 null), and antitumor efficacy was further improved when the virus was combined with the chemotherapeutic drug gemcitabine. The antitumor effect was transient in all tested groups. The developed system can be used to study therapies involving various oncolytic viruses and chemotherapeutics, with the goal of inducing tumor-specific immunity while preventing premature virus clearance. 相似文献
79.
Jigna Shah Prerak T. Desai Dong Chen John R. Stevens Bart C. Weimer 《Applied and environmental microbiology》2013,79(23):7281-7289
Salmonella is an important cause of bacterial food-borne gastroenteritis. Salmonella encounters multiple abiotic stresses during pathogen elimination methods used in food processing, and these stresses may influence its subsequent survivability within the host or in the environment. Upon ingestion, Salmonella is exposed to gastrointestinal acidity, a first line of the host innate defense system. This study tested the hypothesis that abiotic stresses encountered during food processing alter the metabolic mechanisms in Salmonella that enable survival and persistence during subsequent exposure to the host gastrointestinal acidic environment. Out of the four different abiotic stresses tested, viz., cold, peroxide, osmotic, and acid, preadaptation of the log-phase culture to cold stress (5°C for 5 h) significantly enhanced survival during subsequent acid stress (pH 4.0 for 90 min). The gene expression profile of Salmonella preadapted to cold stress revealed induction of multiple genes associated with amino acid metabolism, oxidative stress, and DNA repair, while only a few of the genes in the above-mentioned stress response and repair pathways were induced upon exposure to acid stress alone. Preadaptation to cold stress decreased the NAD+/NADH ratio and hydroxyl (OH·) radical formation compared with those achieved with the exposure to acid stress alone, indicating alteration of aerobic respiration and the oxidative state of the bacteria. The results from this study suggest that preadaptation to cold stress rescues Salmonella from the deleterious effect of subsequent acid stress exposure by induction of genes involved in stress response and repair pathways, by modification of aerobic respiration, and by redox modulation. 相似文献
80.