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121.
We have previously reported that Tamarix gallica caused a marked inhibition of thioacetamide-induced hepatotoxicity, oxidative damage and early tumor promotion related events in the liver. These results strongly indicates that T. gallica may have chemopreventive potential. Therefore, in the present study, we examined the inhibitory effects of T. gallica methanolic extract on diethylnitrosamine (DEN) initiated and 2-acetyl aminofluorene (2-AAF) promoted liver carcinogenesis in male Wistar rats. Interestingly, it was found that T. gallica (25 and 50 mg/kg body wt.) resulted in a marked reduction of the incidence of liver tumors. The study was further histologically confirmed. Furthermore to understand the underlying mechanisms of chemopreventive action by T. gallica we evaluated the levels activities of hepatic antioxidant defense enzymes, ornithine decarboxylase activity and hepatic DNA synthesis as a marker for tumor promotion since direct correlation between these marker parameters and carcinogenicity have been well documented. Treatment of male Wistar rats for five consecutive days with 2-AAF i.p. induced significant hepatic toxicity, oxidative stress and hyperproliferation. Pretreatment of T. gallica extract (25 and 50 mg/kg body wt.) prevented oxidative stress by restoring the levels of antioxidant enzymes and also prevented toxicity at both the doses. The promotion parameters induced (ornithine decarboxylase activity and DNA synthesis) by 2-AAF administration in diet with partial hepatectomy (PH) were also significantly suppressed dose-dependently by T. gallica. Therefore, we can conclude that ultimately the protection against liver carcinogenesis by T. gallica methanolic extract might be mediated by multiple actions, which include restoration of cellular antioxidant enzymes, detoxifying enzymes, ODC activity and DNA synthesis. 相似文献
122.
Background
Avian reoviruses replicate in viral factories, which are dense cytoplasmic compartments estabilished by protein-protein interactions. The non-structural protein muNS forms the factory scaffold that attracts other viral components in a controlled fashion. To create such a three-dimensional network, muNS uses several different self-interacting domains.Methodology/Principal Findings
In this study we have devised a strategy to identify muNS regions containing self-interacting domains, based on the capacity of muNS-derived inclusions to recruit muNS fragments. The results revealed that the muNS region consisting of residues 477–542 was recruited with the best efficiency, and this raised the idea of using this fragment as a molecular tag for delivering foreign proteins to muNS inclusions. By combining such tagging system with our previously established method for purifying muNS inclusions from baculovirus-infected insect cells, we have developed a novel protein purification protocol.Conclusions/Significance
We show that our tagging and inclusion-targeting system can be a simple, versatile and efficient method for immobilizing and purifying active proteins expressed in baculovirus-infected cells. We also demonstrate that muNS inclusions can simultaneously recruit several tagged proteins, a finding which may be used to generate protein complexes and create multiepitope particulate material for immunization purposes. 相似文献123.
Juergen Kreyling Mohammed A. S. Arfin Khan Fahmida Sultana Wolfgang Babel Carl Beierkuhnlein Thomas Foken Julia Walter Anke Jentsch 《Ecosystems》2017,20(2):301-315
Extreme drought events challenge ecosystem functioning. Ecological response to drought is studied worldwide in a growing number of field experiments by rain-out shelters. Yet, few meta-analyses face severe challenges in the comparability of studies. This is partly because build-up of drought stress in rain-out shelters is modified by ambient weather conditions. Rain-out shelters can further create confounding effects (radiation, temperature), which may influence plant responses. Yet, a quantification of ecophysiological effects within rain-out shelters under opposing ambient weather conditions and of microclimatological artifacts is missing. Here, we examined phytometers—standardized potted individuals of Plantago lanceolata—under rain-out shelter, rain-out shelter artifact control, and ambient control during opposing outside microclimatological conditions. Furthermore, we tested for artifacts of rain-out shelters on plant responses in a long-term semi-natural grassland experiment. Phytometer plants below the rain-out shelters showed lower stomatal conductance, maximum quantum efficiency, and leaf water potential during warm ambient conditions with high evaporative demand than during cold conditions with low evaporative demand. Plant performance was highly correlated with ambient temperature and vapor pressure deficit (VPD). Rain-out shelter artifacts on plant responses were nonsignificant. Rain-out shelters remain a viable tool for studying ecosystem responses to drought. However, drought manipulations using rain-out shelters are strongly modified by ambient weather conditions. Attributing the results from rain-out shelter studies to drought effects and comparability among studies and study years therefore requires the quantification of the realized drought stress, for example, by relating ecosystem responses to measured microclimatological parameters such as air temperature and VPD. 相似文献
124.
Shi Yang Li Wei Yu Yao Yong Jin Yuan Wen Shu Tay Nian-Lin Reena Han Rehena Sultana Pryseley N. Assam Alex Tiong-Heng Sia Ban Leong Sng 《BMC anesthesiology》2017,17(1):169
Background
The Supreme? laryngeal mask airway (SLMA) is a single-use LMA with double lumen design that allows separation of the respiratory and the alimentary tract, hence potentially reducing the gastric volume and risk of aspiration. The purpose of this prospective cohort study is to evaluate the the role of the SLMA as an airway technique for women undergoing category 2 and 3 Cesarean delivery under general anesthesia.Methods
We recruited 584 parturients who underwent category 2 or 3 Cesarean delivery under general anesthesia, in which 193 parturients underwent category 2 and 391 parturients underwent category 3 Cesarean delivery. The primary outcome was insertion success rate at 1st attempt in SLMA insertion. The secondary outcomes included anaesthetic, obstetric outcomes and maternal side effects associated with airway device.Results
The 1st attempt insertion success rate was 98.3%, while the overall insertion success rate was 100%. The mean (Standard deviation) time to effective ventilation was 15.6 (4.4) seconds. Orogastric tube insertion was successful at the 1st attempt in all parturients. There was no clinical evidence of aspiration or regurgitation. No episodes of hypoxemia, laryngospasm or bronchospasm were observed intra-operatively. The incidence of complications was low and with good maternal satisfaction reported.Conclusions
The SLMA could be an alternative effective airway in category 2 and 3 parturients emergency Cesarean Delivery under general anesthesia in a carefully-selected obstetric population.Trial registration
Clinical Trials Registration: Clinicaltrials.gov Registration NCT02026882. Registered on December 31, 2013.125.
Biological fluids contain a very high total concentration of macromolecules that leads to volume exclusion by one molecule to another. Theory and experiment have shown that this condition, termed macromolecular crowding, can have significant effects on molecular recognition. However, the influence of molecular crowding on recognition events involving virus particles, and their inhibition by antiviral compounds, is virtually unexplored. Among these processes, capsid self-assembly during viral morphogenesis and capsid-cell receptor recognition during virus entry into cells are receiving increasing attention as targets for the development of new antiviral drugs. In this study, we have analyzed the effect of macromolecular crowding on the inhibition of these two processes by peptides. Macromolecular crowding led to a significant reduction in the inhibitory activity of: 1), a capsid-binding peptide and a small capsid protein domain that interfere with assembly of the human immunodeficiency virus capsid, and 2), a RGD-containing peptide able to block the interaction between foot-and-mouth disease virus and receptor molecules on the host cell membrane (in this case, the effect was dependent on the conditions used). The results, discussed in the light of macromolecular crowding theory, are relevant for a quantitative understanding of molecular recognition processes during virus infection and its inhibition. 相似文献
126.
Rodríguez-Díaz J Montava R Viana R Buesa J Pérez-Martínez G Monedero V 《Biotechnology letters》2011,33(6):1169-1175
The efficacy of recombinant Lactococcus lactis as a delivery vehicle for a rotavirus antigen was evaluated in a mouse model. The rotavirus VP8* protein was expressed intracellularly
and extracellularly in L. lactis wild type and in an alr mutant deficient in alanine racemase activity, necessary for the synthesis of the cell-wall component d-alanine. When the mucosal immune response was evaluated by measuring VP8*-specific IgA antibody in faeces, wild-type L. lactis triggered a low IgA synthesis only when the secreting strain was used. In contrast, VP8*-specific IgA was detected in faeces
of both groups of mice orally given the alr mutant expressing extracellular VP8* and intracellular VP8*, which reached levels similar to that obtained with the wild
type secreting strain. However, oral administration of the recombinant strains did not induce serum IgG or IgA responses.
L. lactis cell-wall mutants may therefore provide certain advantages when low-antigenic proteins are expressed intracellularly. However,
the low immune response obtained by using this antigen-bacterial host combination prompts to the use of new strains and vaccination
protocols in order to develop acceptable rotavirus immunization levels. 相似文献
127.
Muñoz JA Chenoll E Casinos B Bataller E Ramón D Genovés S Montava R Ribes JM Buesa J Fàbrega J Rivero M 《Applied and environmental microbiology》2011,77(24):8775-8783
Rotavirus is the leading cause of severe acute gastroenteritis among children worldwide. It is well known that breast-feeding and vaccination afford infants protection. Since breast-feeding has drastically decreased in developed countries, efforts have been focused on the potential use of probiotics as preventive agents. In this study, a novel Bifidobacterium longum subsp. infantis strain was isolated from infant feces and selected, based on its capacity to inhibit in vitro rotavirus Wa replication (up to 36.05% infectious foci reduction) and also to protect cells from virus infection (up to 48.50% infectious foci reduction) in both MA-104 and HT-29 cell lines. Furthermore, studies using a BALB/c mouse model have proved that this strain provides preliminary in vivo protection against rotavirus infection. The strain has been deposited in the Spanish Type Culture Collection under the accession number CECT 7210. This novel strain has the main properties required of a probiotic, such as resistance to gastrointestinal juices, biliary salts, NaCl, and low pH, as well as adhesion to intestinal mucus and sensitivity to antibiotics. The food safety status has been confirmed by the absence of undesirable metabolite production and in acute ingestion studies of mice. Overall, these results demonstrate that Bifidobacterium longum subsp. infantis CECT 7210 can be considered a probiotic able to inhibit rotavirus infection. 相似文献
128.
129.
Sultana Juhara Mannan Mohammad Abul Kalam Azad Md. Ashik Ullah Abdullah Al Maruf Md. Israt Rayhan Mohammad Shamsul Ahsan Abul Hasnat 《Biological trace element research》2011,140(3):272-283
Drug abuser patients (n = 104), age ranging from 19 to 42 years, were randomly recruited to investigate the serum levels of trace elements (Cu, Zn,
Fe, and Mg), malondialdehyde (MDA), and immunoglobulin (IgG, IgA, and IgM) before and after clinical intervention. Control
group also included 104 healthy individuals. Blood samples were analyzed for determining trace elements, MDA, and immunoglobulin
using atomic absorption spectroscopy, Ultraviolet-Visible (UV-VIS) spectroscopy, and turbidimetry method, respectively. For
serum level of Zn and Fe, the differences between the groups (before intervention, after intervention, and control) were not
significant (p > 0.05). However, significant differences were found in serum copper levels between control group, drug abuser patients,
and before and after intervention (p < 0.05). The concentration of Mg was found to be significantly higher (p = 0.007) in drug abuser patients than the controls, and after intervention, the level was restored to control value. A displacement
of elemental homeostasis was observed in drug abuser patients compared to control, and it was improved after intervention.
An increase in serum concentration of MDA was found in drug abuser patients compared to control subjects (p > 0.05) but was not statistically significant. After intervention, the concentration was restored to control value (p > 0.05). The serum concentrations of IgA and IgM were found to be significantly higher (p < 0.05) in drug abuser patients before intervention than the controls, and the level tended to be restored to control level
after clinical intervention. Serum IgG level was found to be lower in drug abuser patients compared to controls and further
declined significantly (p < 0.05) after intervention. These findings may suggest a possible imbalance in the levels of micronutrients, antioxidants,
and immunoglobulin in drug abuser patients, which tend to be restored to control values after detoxification. 相似文献
130.