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41.
Anthrax lethal toxin (LT) and edema toxin (ET) are the major virulence factors of anthrax and can replicate the lethality and symptoms associated with the disease. This review provides an overview of our current understanding of anthrax toxin effects in animal models and the cytotoxicity (necrosis and apoptosis) induced by LT in different cells. A brief reexamination of early historic findings on toxin in vivo effects in the context of our current knowledge is also presented. 相似文献
42.
Guan-Sheng Jiao Seongjin Kim Mahtab Moayeri April Thai Lynne Cregar-Hernandez Linda McKasson Sean OMalley Stephen H. Leppla Alan T. Johnson 《Bioorganic & medicinal chemistry letters》2018,28(2):134-139
Anthrax is a highly lethal disease caused by the Gram-(+) bacteria Bacillus anthracis. Edema toxin (ET) is a major contributor to the pathogenesis of disease in humans exposed to B. anthracis. ET is a bipartite toxin composed of two proteins secreted by the vegetative bacteria, edema factor (EF) and protective antigen (PA). Our work towards identifying a small molecule inhibitor of anthrax edema factor is the subject of this letter. First we demonstrate that the small molecule probe 5′-Fluorosulfonylbenzoyl 5′-adenosine (FSBA) reacts irreversibly with EF and blocks enzymatic activity. We then show that the adenosine portion of FSBA can be replaced to provide more drug-like molecules which are up to 1000-fold more potent against EF relative to FSBA, display low cross reactivity when tested against a panel of kinases, and are nanomolar inhibitors of EF in a cell-based assay of cAMP production. 相似文献
43.
Rapeephan R. Maude Md Amir Hossain Mahtab Uddin Hassan Sophie Osbourne Katherine Langan Abu Sayeed Mohammed Rezaul Karim Rasheda Samad Shyamanga Borooah Bal Dhillon Nicholas P. J. Day Arjen M. Dondorp Richard J. Maude 《PloS one》2013,8(12)
Introduction
Measurement of optic nerve sheath diameter (ONSD) by ultrasound is increasingly used as a marker to detect raised intracranial pressure (ICP). ONSD varies with age and there is no clear consensus between studies for an upper limit of normal. Knowledge of normal ONSD in a healthy population is essential to interpret this measurement.Methods
In a prospective observational study, ONSD was measured using a 15 MHz ultrasound probe in healthy volunteers in Chittagong, Bangladesh. The aims were to determine the normal range of ONSD in healthy Bangladeshi adults and children, compare measurements in males and females, horizontal and vertical beam orientations and left and right eyes in the same individual and to determine whether ONSD varies with head circumference independent of age.Results
136 subjects were enrolled, 12.5% of whom were age 16 or under. Median ONSD was 4.41 mm with 95% of subjects in the range 4.25–4.75 mm. ONSD was bimodally distributed. There was no relationship between ONSD and age (≥4 years), gender, head circumference, and no difference in left vs right eye or horizontal vs vertical beam.Conclusions
Ultrasonographic ONSD in Bangladeshi healthy volunteers has a narrow bimodal distribution independent of age (≥4 years), gender and head circumference. ONSD >4.75 mm in this population should be considered abnormal. 相似文献44.
Chondrogenic differentiation of human scalp adipose‐derived stem cells in Polycaprolactone scaffold and using Freeze Thaw Freeze method 下载免费PDF全文
45.
Maude RJ Hoque G Hasan MU Sayeed A Akter S Samad R Alam B Yunus EB Rahman R Rahman W Chowdhury R Seal T Charunwatthana P Chang CC White NJ Faiz MA Day NP Dondorp AM Hossain A 《PloS one》2011,6(11):e27273
Background
Early start of enteral feeding is an established treatment strategy in intubated patients in intensive care since it reduces invasive bacterial infections and length of hospital stay. There is equipoise whether early enteral feeding is also beneficial in non-intubated patients with cerebral malaria in resource poor settings. We hypothesized that the risk of aspiration pneumonia might outweigh the potential benefits of earlier recovery and prevention of hypoglycaemia.Method and Findings
A randomized trial of early (day of admission) versus late (after 60 hours in adults or 36 hours in children) start of enteral feeding was undertaken in patients with cerebral malaria in Chittagong, Bangladesh from May 2008 to August 2009. The primary outcome measures were incidence of aspiration pneumonia, hypoglycaemia and coma recovery time. The trial was terminated after inclusion of 56 patients because of a high incidence of aspiration pneumonia in the early feeding group (9/27 (33%)), compared to the late feeding group (0/29 (0%)), p = 0.001). One patient in the late feeding group, and none in the early group, had hypoglycaemia during admission. There was no significant difference in overall mortality (9/27 (33%) vs 6/29 (21%), p = 0.370), but mortality was 5/9 (56%) in patients with aspiration pneumonia.Conclusions
In conclusion, early start of enteral feeding is detrimental in non-intubated patients with cerebral malaria in many resource-poor settings. Evidence gathered in resource rich settings is not necessarily transferable to resource-poor settings.Trial Registration
Controlled-Trials.com ISRCTN57488577 相似文献46.
Hatav Ghasemi Tehrani Keihaneh Aasasi Farahnaz Mardanian Ferdous Mehrabian Minoo Movahedi Elham Naghshineh 《Reports of Biochemistry & Molecular Biology》2022,11(3):386
Background:This study aims to evaluate the effect of Letrozole (LE) in reducing ovarian hyperstimulation syndrome (OHSS) in high-risk participants with polycystic ovary syndrome (PCOS) treated with In vitro fertilization (IVF).Methods:This study was a randomized clinical trial in which participants were randomly divided into two groups (n= 25 per group). Based on GnRH-antagonist protocol, recombinant follicle-stimulating hormone 150 units/day subcutaneously and human menopausal gonadotropin 75 units/ day intramuscularly used from day 2 of the menstrual cycle. In the study group, Letrozole 5 mg daily was added simultaneously with gonadotropin during the first five days of the IVF cycle and in the control group placebo was added.Results:There were statistically significant differences among the groups in terms of Estradiol level on Trigger Day (p= 0.04). The total days of stimulation and cumulative Gonadotropin dose were significantly lower in the Letrozole group (p= 0.00). There were no significant differences between the groups in terms of the number of oocytes retrieved, numbers of implanted embryos, and clinical pregnancy rates (p-value> 0.05). There was only one moderate case in the intervention group and 9 moderate symptoms in the control group (p= 0.04).DiscussionAdministration of Letrozole with GnRH antagonist protocol, conventional protocol in PCOS cases in IVF cycle, had a significant effect on reducing the incidence of OHSS. So, if the future studies prove LE co-administration may lessen the incidence of OHSS, LE will be a highly potent drug for preventing OHSS in PCOS cases.Key Words: In vitro fertilization, Infertility, Letrozole, Ovarian hyperstimulation syndrome 相似文献
47.
Amniotic membrane (AM), the innermost layer of the fetal membranes, has been widely employed in the surgical reconstruction and tissue engineering. Expression of the antimicrobial peptides such as defensins, elafin and SLPI which are essential elements of the innate immune system results in antibacterial properties of the AM. Preservation is necessary to reach a ready-to-use source of the AM. However, these methods might change the properties of the AM. The aim of this study was to evaluate antibacterial properties of the AM after preservation. Antibacterial property of the fresh AM was compared with cryopreserved and freeze-dried AM by modified disk diffusion method. Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922 and two clinical isolated strains of E. coli were cultured in Mueller Hinton agar and a piece of the AM was placed on agar surface. After 24 h incubation, the inhibition zone was measured. In addition, one of the most important antibacterial peptides, elafin, was measured by ELISA assay before and after preservations procedures. Antibacterial properties of the AM were maintained after cryopreservation and freeze-drying. However, the inhibition zone was depending on the bacterial strains. The cryopreservation and freeze-drying procedures significantly decreased elafin which shows that antibacterial property is not limited to the effects of amniotic cells and the other components such as extracellular matrix may contribute in antibacterial effects. The promising results of this study show that the preserved AM is a proper substitute of the fresh AM to be employed in clinical situations. 相似文献
48.
Tanuj Sharma Mohammed Abohashrh Mohammad Hassan Baig Jae-June Dong Mohammad Mahtab Alam Irfan Ahmad Safia Irfan 《Saudi Journal of Biological Sciences》2021,28(5):3152-3159
Although several pharmacological agents are under investigation to be repurposed as therapeutic against COVID-19, not much success has been achieved yet. So, the search for an effective and active option for the treatment of COVID-19 is still a big challenge. The Spike protein (S), RNA-dependent RNA polymerase (RdRp), and Main protease (Mpro) are considered to be the primary therapeutic drug target for COVID-19. In this study we have screened the drugbank compound library against the Main Protease. But our search was not limited to just Mpro. Like other viruses, SARS-CoV-2, have also acquired unique mutations. These mutations within the active site of these target proteins may be an important factor hindering effective drug candidate development. In the present study we identified important active site mutations within the SARS-CoV-2 Mpro (Y54C, N142S, T190I and A191V). Further the drugbank database was computationally screened against Mpro and the selected mutants. Finally, we came up with the common molecules effective against the wild type (WT) and all the selected Mpro. The study found Imiglitazar, was found to be the most active compound against the wild type of Mpro. While PF-03715455 (Y54C), Salvianolic acid A (N142S and T190I), and Montelukast (A191V) were found to be most active against the other selected mutants. It was also found that some other compounds such as Acteoside, 4-Amino-N- {4-[2-(2,6-Dimethyl-Phenoxy)-Acetylamino]-3-Hydroxy-1-Isobutyl-5-Phenyl-Pentyl}-Benzamide, PF-00610355, 4-Amino-N-4-[2-(2,6-Dimethyl-Phenoxy)-Acetylamino]-3-Hydroxy-1-Isobutyl-5-Phenyl-Pentyl}-Benzamide and Atorvastatin were showing high efficacy against the WT as well as other selected mutants. We believe that these molecules will provide a better and effective option for the treatment of COVID-19 clinical manifestations. 相似文献
49.
Rezakhani Leila Motesharezadeh Babak Tehrani Mohammad Mehdi Etesami Hassan Hosseini Hossein Mirseyed 《Plant and Soil》2022,477(1-2):259-280
Plant and Soil - It is known that the single and combined use of phosphate-solubilizing bacteria (PSB) and silicon (Si) have the potential to improve the uptake of phosphorus (P) by plants... 相似文献
50.
Zamani M Sharifi Tehrani A Ali Abadi AA 《Communications in agricultural and applied biological sciences》2007,72(4):773-777
The aim of this research was to determine if the attacks of green mold on orange could be reduced by edible salts alone or in combination with biocontrol agent. For this purpose toxicity to Pantoea digitatum and practical use of sodium carbonate (SC), sodium bicarbonate (SBC) and potassium carbonate, and potassium bicarbonate alone or in combination with antagonistic bacteria (Pseudomonas fluorescens isolate PN, Bacillus subtilis isolate VHN, Pantoea agglomerans isolate CA) to control green mold were determined. All were fungistatic. SC and SBC were equal and superior to the other salts for control of green mold on oranges inoculated 6h before treatment and were chosen for subsequent trails under cold storage conditions. The biocontrol agents were found completely tolerant to 3% sodium bicarbonate and sodium carbonate at room temperature; although their culturability was reduced by > 1000-fold after 60 min in 1% other salt solutions. Satisfactory results were also obtained with the combined treatment for control of green mold. A significant increase in biocontrol activity of all isolate was observed when combined with sodium carbonate and sodium bicarbonate. The treatments comprising CA combined with SB was as effective as fungicide treatment. Thus, use of sodium bicarbonate treatment at 3% followed by the antagonist P. agglomerans CA could be an alternative to chemical fungicides for control of green mold on oranges. 相似文献