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121.
María-Angeles Aller Jorge-Luis Arias Arturo Cruz Jaime Arias 《Theoretical biology & medical modelling》2007,4(1):1-25
Background
Portal hypertension is a clinical syndrome that manifests as ascites, portosystemic encephalopathy and variceal hemorrhage, and these alterations often lead to death.Hypothesis
Splanchnic and/or systemic responses to portal hypertension could have pathophysiological mechanisms similar to those involved in the post-traumatic inflammatory response. The splanchnic and systemic impairments produced throughout the evolution of experimental prehepatic portal hypertension could be considered to have an inflammatory origin. In portal vein ligated rats, portal hypertensive enteropathy, hepatic steatosis and portal hypertensive encephalopathy show phenotypes during their development that can be considered inflammatory, such as: ischemia-reperfusion (vasodilatory response), infiltration by inflammatory cells (mast cells) and bacteria (intestinal translocation of endotoxins and bacteria) and lastly, angiogenesis. Similar inflammatory phenotypes, worsened by chronic liver disease (with anti-oxidant and anti-enzymatic ability reduction) characterize the evolution of portal hypertension and its complications (hepatorenal syndrome, ascites and esophageal variceal hemorrhage) in humans.Conclusion
Low-grade inflammation, related to prehepatic portal hypertension, switches to high-grade inflammation with the development of severe and life-threatening complications when associated with chronic liver disease. 相似文献122.
Mendes GD Hamamoto D Ilha J Pereira Ados S De Nucci G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):553-559
A rapid, sensitive and specific method for quantifying the aromatase inhibitor (anastrozole) in human plasma using dexchlorpheniramine as the internal standard (I.S.) is described herein. The analyte and the I.S. were extracted from 200 microl of human plasma by liquid-liquid extraction using a mixture of diethyl ether:dichloromethane (70:30, v/v) solution. Extracts were removed and dried in the organic phase then reconstituted with 200 microl of acetonitrile:water (50:50; v/v). The extracts were analyzed by high performance liquid chromatography coupled with photospray tandem mass spectrometry (HPLC-MS-MS). Chromatography was performed isocratically on a Genesis, C18 4 microm analytical column (100 mm x 2.1mm i.d.). The method had a chromatographic run time of 2.5 min and a linear calibration curve ranging from 0.05-10 ng ml(-1). The limit of quantification (LOQ) was 0.05 ng ml(-1). This HPLC-MS-MS procedure was used to assess pharmacokinetic studies. 相似文献
123.
Pereira LA Báo SN Barbosa MS da Silva JL Felipe MS de Santana JM Mendes-Giannini MJ de Almeida Soares CM 《FEMS yeast research》2007,7(8):1381-1388
Paracoccidioides brasiliensis is an important fungal pathogen. The disease it causes, paracoccidioidomycosis (PCM), ranges from localized pulmonary infection to systemic processes that endanger the life of the patient. Paracoccidioides brasiliensis adhesion to host tissues contributes to its virulence, but we know relatively little about molecules and the molecular mechanisms governing fungal adhesion to mammalian cells. Triosephosphate isomerase (TPI: EC 5.3.1.1) of P. brasiliensis (PbTPI) is a fungal antigen characterized by microsequencing of peptides. The protein, which is predominantly expressed in the yeast parasitic phase, localizes at the cell wall and in the cytoplasmic compartment. TPI and the respective polyclonal antibody produced against this protein inhibited the interaction of P. brasiliensis to in vitro cultured epithelial cells. TPI binds preferentially to laminin, as determined by peptide inhibition assays. Collectively, these results suggest that TPI is required for interactions between P. brasiliensis and extracellular matrix molecules such as laminin and that this interaction may play an important role in the fungal adherence and invasion of host cells. 相似文献
124.
Marqus Laura Peltier Drew M. P. Camarero J. Julio Zavala Miguel A. Madrigal-Gonzlez Jaime Sangesa-Barreda Gabriel Ogle Kiona 《Ecosystems》2022,25(1):215-235
Ecosystems - Legacies of past climate conditions and historical management govern forest productivity and tree growth. Understanding how these processes interact and the timescales over which they... 相似文献
125.
Edgardo Cruces Ralf Rautenberger Víctor Mauricio Cubillos Eduardo Ramírez‐Kushel Yesenia Rojas‐Lillo Carlos Lara Jaime Andrs Montory Ivn Gmez 《Journal of phycology》2019,55(5):1011-1027
Species of the genus Ulva (Chlorophyta) are regarded as opportunistic organisms, which efficiently adjust their metabolism to the prevailing environmental conditions. In this study, changes in chlorophyll‐a fluorescence‐based photoinhibition of photosynthesis, electron transport rates, photosynthetic pigments, lipid peroxidation, total phenolic compounds, and antioxidant metabolism were investigated during a diurnal cycle of natural solar radiation in summer (for 12 h) under two treatments: photosynthetically active radiation (PAR: 400–700 nm) and PAR+ ultraviolet (UV) radiation (280–700 nm). In the presence of PAR alone, Ulva rigida showed dynamic photoinhibition, and photosynthetic parameters and pigment concentrations decreased with the intensification of the radiation. On the other hand, under PAR+UV conditions a substantial decline up to 43% was detected and an incomplete fluorescence recovery, also, P‐I curve values remained low in relation to the initial condition. The phenolic compounds increased their concentration only in UV radiation treatments without showing a correlation with the antioxidant activity. The enzimatic activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX) increased over 2‐fold respect at initial values during the onset of light intensity. In contrast, catalase (CAT) increased its activity rapidly in response to the radiation stress to reach maxima at 10 a.m. and decreasing during solar. The present study suggests that U. rigida is capable of acclimating to natural radiation stress relies on a concerted action of various physiological mechanisms that act at different times of the day and under different levels of environmental stress. 相似文献
126.
Dobránszki Judit Hidvégi Norbert Gulyás Andrea Teixeira da Silva Jaime A. 《Plant molecular biology》2019,100(4-5):511-525
Plant Molecular Biology - In response to an ultrasound pulse, several hundred DEGs, including in response to stress, were up- or down-regulated in in vitro potato plantlets. Despite this abiotic... 相似文献
127.
Fiona McQuaid Rachel Mulholland Yuma Sangpang Rai Utkarsh Agrawal Helen Bedford J. Claire Cameron Cheryl Gibbons Partho Roy Aziz Sheikh Ting Shi Colin R. Simpson Judith Tait Elise Tessier Steve Turner Jaime Villacampa Ortega Joanne White Rachael Wood 《PLoS medicine》2022,19(2)
BackgroundIn 2020, the SARS-CoV-2 (COVID-19) pandemic and lockdown control measures threatened to disrupt routine childhood immunisation programmes with early reports suggesting uptake would fall. In response, public health bodies in Scotland and England collected national data for childhood immunisations on a weekly or monthly basis to allow for rapid analysis of trends. The aim of this study was to use these data to assess the impact of different phases of the pandemic on infant and preschool immunisation uptake rates.Methods and findingsWe conducted an observational study using routinely collected data for the year prior to the pandemic (2019) and immediately before (22 January to March 2020), during (23 March to 26 July), and after (27 July to 4 October) the first UK “lockdown”. Data were obtained for Scotland from the Public Health Scotland “COVID19 wider impacts on the health care system” dashboard and for England from ImmForm.Five vaccinations delivered at different ages were evaluated; 3 doses of “6-in-1” diphtheria, tetanus, pertussis, polio, Haemophilus influenzae type b, and hepatitis B vaccine (DTaP/IPV/Hib/HepB) and 2 doses of measles, mumps, and rubella (MMR) vaccine. This represented 439,754 invitations to be vaccinated in Scotland and 4.1 million for England. Uptake during the 2020 periods was compared to the previous year (2019) using binary logistic regression analysis. For Scotland, uptake within 4 weeks of a child becoming eligible by age was analysed along with geographical region and indices of deprivation. For Scotland and England, we assessed whether immunisations were up-to-date at approximately 6 months (all doses 6-in-1) and 16 to 18 months (first MMR) of age.We found that uptake within 4 weeks of eligibility in Scotland for all the 5 vaccines was higher during lockdown than in 2019. Differences ranged from 1.3% for first dose 6-in-1 vaccine (95.3 versus 94%, odds ratio [OR] compared to 2019 1.28, 95% confidence intervals [CIs] 1.18 to 1.39) to 14.3% for second MMR dose (66.1 versus 51.8%, OR compared to 2019 1.8, 95% CI 1.74 to 1.87). Significant increases in uptake were seen across all deprivation levels.In England, fewer children due to receive their immunisations during the lockdown period were up to date at 6 months (6-in-1) or 18 months (first dose MMR). The fall in percentage uptake ranged from 0.5% for first 6-in-1 (95.8 versus 96.3%, OR compared to 2019 0.89, 95% CI 0.86– to 0.91) to 2.1% for third 6-in-1 (86.6 versus 88.7%, OR compared to 2019 0.82, 95% CI 0.81 to 0.83).The use of routinely collected data used in this study was a limiting factor as detailed information on potential confounding factors were not available and we were unable to eliminate the possibility of seasonal trends in immunisation uptake.ConclusionsIn this study, we observed that the national lockdown in Scotland was associated with an increase in timely childhood immunisation uptake; however, in England, uptake fell slightly. Reasons for the improved uptake in Scotland may include active measures taken to promote immunisation at local and national levels during this period and should be explored further. Promoting immunisation uptake and addressing potential vaccine hesitancy is particularly important given the ongoing pandemic and COVID-19 vaccination campaigns.Fiona McQuaid and colleagues assess the uptake of infant and pre-school immunisations in Scotland and England during the COVID-19 pandemic. 相似文献
128.
129.
Avila C R Cantón F Barnestein P Suárez MF Marraccini P Rey M Humara JM Ordás R M Cánovas F 《Physiologia plantarum》2001,112(3):388-396
130.
Culebras E Martínez E Carnero A Malpartida F 《Molecular & general genetics : MGG》1999,262(4-5):730-737
In a search for activators of secondary metabolism we isolated a 12.6-kb DNA fragment from a genomic library of Streptomyces ambofaciens NRRL 2240 (the spiramycin producer ). Sequencing of 6 kb of the cloned fragment revealed a cluster of four ORFs (ORF1–4)
whose deduced products showed similarities to those of other genes involved in polyketide biosynthesis, including a pathway-specific
regulatory gene of the SARP family. The results of insertional inactivation of some of the cloned genes clearly indicate that
the isolated cluster does not code for spiramycin production, suggesting that some other polyketide compound might well be
produced by this strain.
Received: 14 May 1999 / Accepted: 28 July 1999 相似文献