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961.
962.
The physicochemical, immunologic, and biologic relationships between humam lymphotoxins (LT) and interferons (IF) present in supernatant fluids from lectin-stimulated peripheral blood lymphocytes (PBL) and a continuous B-lymphoblastoid cell line (PGLC-33h) were analyzed. LT activity obtained from lectin-activated PBL could not be resolved from IF activity by gel filtration chromatography. LT activity eluted in multiple peaks of activity at 70 to 90,000, and 40 to 50,000 m.w., characteristic of alpha and beta LT, respectively. IF activity in these supernatant fluids eluted as a broad band between 35 and 80,000 m.w., also suggestive of molecular heterogeneity. In contrast, this m.w. heterogeneity was not observed in LT and IF activities obtained from the PGLC-33h cell line. LT and IF eluted as separate peaks of activity at 90,000 and 25,000 m.w., respectively. In addition, acid and heat lability of PGLC-33h IF suggested similarity to type II IF. Immunologic studies, with a rabbit anti-alpha class serum that neutralized LT activity from both PBL and PGLC-33h, did not affect IF activity from either of these sources. Supernatant fluids from PGLC-33h cultures were also capable of inhibiting the proliferation of HeLa cells in vitro. The growth inhibitory activity was attributed to LT- and IF-like molecules. This evidence suggests that although cytotoxic and anti-viral activities were due to separate molecules, LT and IF have overlapping biologic activities in their ability to inhibit the proliferation of cells in vitro. 相似文献
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MD ABDUR RAHIM HOONHEE SEO SUKYUNG KIM YOON KYOUNG JEONG HANIEH TAJDOZIAN MIJUNG KIM SAEBIM LEE HO-YEON SONG 《Polish journal of microbiology》2021,70(1):117
Staphylococcus aureus is currently a significant multidrug-resistant bacterium, causing severe healthcare-associated and community-acquired infections worldwide. The current antibiotic regimen against this pathogen is becoming ineffective due to resistance, in addition, they disrupt the normal microbiota. It highlights the urgent need for a pathogen-specific drug with high antibacterial efficacy against S. aureus. α-Viniferin, a bioactive phytochemical compound, has been reported to have excellent anti-Staphylococcus efficacy as a topical agent. However, so far, there were no clinical trials that have been conducted to elucidate its efficacy. The present study aimed to investigate the antibacterial efficacy of α-viniferin against S. aureus in a ten-day clinical trial. Based on the results, α-viniferin showed 50% minimum inhibitory concentrations (MIC50 values) of 7.8 μg/ml in culture broth medium. α-Viniferin was administered in the nares three times a day for ten days using a sterile cotton swab stick. Nasal swab specimens were collected before (0 days) and after finishing the trial (10th day), and then analyzed. In the culture and RT-PCR-based analysis, S. ureus was reduced significantly: 0.01. In addition, 16S ribosomal RNA-based amplicon sequencing analysis showed that S. aureus reduced from 51.03% to 23.99% at the genus level. RNA-seq analysis was also done to gain insights into molecular mechanisms of α-viniferin against S. aureus, which revealed that some gene groups were reduced in 5-fold FC cutoff at two times MIC conditions. The study results demonstrate α-viniferin as a potential S. aureus-specific drug candidate. 相似文献
964.
L. Pe?a M. Ikenberry B. Ware K. L. Hohn D. Boyle X. S. Sun D. Wang 《Biotechnology and Bioprocess Engineering》2011,16(6):1214-1222
Mineral acids have been used effectively for the pretreatment of cellulosic biomass to improve sugar recovery and promote
its conversion to ethanol; however, substantial capital investment is required to enable separation of the acid, and corrosion-resistant
materials are necessary. Disposal and neutralization costs are also concerns because they can decrease the economic feasibility
of the process. In this work, three acid-functionalized nanoparticles were synthesized for pretreatment and hydrolysis of
lignocellulosic biomass. Silica-protected cobalt spinel ferrite nanoparticles were functionalized with perfluoroalkylsulfonic
acid (PFS), alkylsulfonic acid (AS), and butylcarboxylic acid (BCOOH) groups. These nanoparticles were magnetically separated
from the reaction media and reused. TEM images showed that the average diameter was 2 nm for both PFS and BCOOH nanoparticles
and 7 nm for AS nanoparticles. FTIR confirmed the presence of sulfonic and carboxylic acid functional groups. Ion exchange
titration measurements yielded 0.9, 1.7, and 0.2 mmol H+/g of catalyst for PFS, AS, and BCOOH nanoparticles, respectively. Elemental analysis results indicated that PFS and AS nanoparticles
had 3.1 and 4.9% sulfur, respectively. Cellobiose hydrolysis was used as a model reaction to evaluate the performance of acid-functionalized
magnetic nanoparticles for breaking β-(1→4) glycosidic bonds. Cellobiose conversion of 78% was achieved when using AS nanoparticles
as the catalyst at 175°C for 1 h, which was significantly higher than the conversion for the control experiment (52%). AS
nanoparticles retained more than 60% of their sulfonic acids groups after the first run, and 65 and 60% conversions were obtained
for the second and third runs, respectively. 相似文献
965.
Phinitphong Sarichai MSc Songphon Buddhasiri DVM Georgia E. Walters BSc Banyong Khantawa MSc Thattawan Kaewsakhorn DVM PhD Kanittha Chantarasakha BSc Surapun Tepaamorndech PhD Parameth Thiennimitr MD PhD 《Microbiology and immunology》2020,64(10):679-693
Salmonella enterica serovar Typhimurium (S. Typhimurium [STM]) is a leading cause of nontyphoidal salmonellosis (NTS) worldwide. The pathogenesis of NTS has been studied extensively using a streptomycin-pretreated mouse colitis model with the limited numbers of laboratory STM strains. However, the pathogenicity of the clinically isolated STM (STMC) strains endemic in Thailand in mice has not been explored. The aim of this study was to compare the pathogenicity of STMC strains collected from Northern Thailand with the laboratory STM (IR715) in mice. Five STMC isolates were obtained from the stool cultures of patients with acute NTS admitted to Maharaj Nakorn Chiang Mai Hospital in 2016 and 2017. Detection of virulence genes and sequence type (ST) of the strains was performed. Female C57BL/6 mice were pretreated with streptomycin sulfate 1 day prior to oral infection with STM. On Day 4 postinfection, mice were euthanized, and tissues were collected to analyze the bacterial numbers, tissue inflammation, and cecal histopathological score. We found that all five STMC strains are ST34 and conferred the same or reduced pathogenicity compared with that of IR715 in mice. A strain-specific effect of ST34 on mouse gut colonization was also observed. Thailand STM ST34 exhibited a significant attenuated systemic infection in mice possibly due to the lack of spvABC-containing virulence plasmid. 相似文献
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Wendell Smith Peter Tomasec Rebecca Aicheler Andrea Loewendorf Ivana Nemčovičová Eddie C.Y. Wang Richard J. Stanton Matt Macauley Paula Norris Laure Willen Eva Ruckova Akio Nomoto Pascal Schneider Gabriele Hahn Dirk M. Zajonc Carl F. Ware Gavin W.G. Wilkinson Chris A. Benedict 《Cell host & microbe》2013,13(3):324-335