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41.
Pierachille Santus Antonio Russo Enzo Madonini Luigi Allegra Francesco Blasi Stefano Centanni Antonio Miadonna Gianfranco Schiraldi Sandro Amaducci 《Respiratory research》2012,13(1):95
Background
Environmental pollution is a known risk factor for multiple diseases and furthermore increases rate of hospitalisations. We investigated the correlation between emergency room admissions (ERAs) of the general population for respiratory diseases and the environmental pollutant levels in Milan, a metropolis in northern Italy.Methods
We collected data from 45770 ERAs for respiratory diseases. A time-stratified case-crossover design was used to investigate the association between air pollution levels and ERAs for acute respiratory conditions. The effects of air pollutants were investigated at lag 0 to lag 5, lag 0–2 and lag 3–5 in both single and multi-pollutant models, adjusted for daily weather variables.Results
An increase in ozone (O3) levels at lag 3–5 was associated with a 78% increase in the number of ERAs for asthma, especially during the warm season. Exposure to carbon monoxide (CO) proved to be a risk factor for pneumonia at lag 0–2 and in the warm season increased the risk of ERA by 66%. A significant association was found between ERAs for COPD exacerbation and levels of sulphur dioxide (SO2), CO, nitrate dioxide (NO2), and particulate matter (PM10 and PM2.5). The multipollutant model that includes all pollutants showed a significant association between CO (26%) and ERA for upper respiratory tract diseases at lag 0–2. For chronic obstructive pulmonary disease (COPD) exacerbations, only CO (OR 1.19) showed a significant association.Conclusions
Exposure to environmental pollution, even at typical low levels, can increase the risk of ERA for acute respiratory diseases and exacerbation of obstructive lung diseases in the general population. 相似文献42.
Niels Gregersen Brage S. Andresen Peter Bross Vibeke Winter Niels Rüdiger Stefan Engst Ernst Christensen Daniel Kelly Arnold W. Strauss Steen Kølvraa Lars Bolund Sandro Ghisla 《Human genetics》1991,86(6):545-551
Summary A series of experiments has established the molecular defect in the medium-chain acyl-coenzyme A (CoA) dehydrogenase (MCAD) gene in a family with MCAD deficiency. Demonstration of intra-mitochondrial mature MCAD indistinguishable in size (42.5-kDa) from control MCAD, and of mRNA with the correct size of 2.4 kb, indicated a point-mutation in the coding region of the MCAD gene to be disease-causing. Consequently, cloning and DNA sequencing of polymerase chain reaction (PCR) amplified complementary DNA (cDNA) from messenger RNA of fibroblasts from the patient and family members were performed. All clones sequenced from the patient exhibited a single base substitution from adenine (A) to guanine (G) at position 985 in the MCAD cDNA as the only consistent base-variation compared with control cDNA. In contrast, the parents contained cDNA with the normal and the mutated sequence, revealing their obligate carrier status. Allelic homozygosity in the patient and heterozygosity for the mutation in the parents were established by a modified PCR reaction, introducing a cleavage site for the restriction endonuclease NcoI into amplified genomic DNA containing G985. The same assay consistently revealed A985 in genomic DNA from 26 control individuals. The A to G mutation was introduced into an E. coli expression vector producing mutant MCAD, which was demonstrated to be inactive, probably because of the inability to form active tetrameric MCAD. All the experiments are consistent with the contention that the G985 mutation, resulting in a lysine to glutamate shift at position 329 in the MCAD polypeptide chain, is the genetic cause of MCAD deficiency in this family. We found the same mutation in homozygous form in 11 out of 12 other patients with verified MCAD deficiency. 相似文献
43.
Câmara Paulo E. A. S. Convey Peter Rangel Sandro B. Konrath Marcelo Barreto Cristine Chaves Pinto Otavio H. B. Silva Micheline Carvalho Henriques Diego Knop de Oliveira Hermeson Cassiano Rosa Luiz H. 《Extremophiles : life under extreme conditions》2021,25(4):369-384
Extremophiles - As part of the reconstruction of the Brazilian Antarctic Station on King George Island, three areas of moss carpet were transplanted to minimize the impact of the new facilities on... 相似文献
44.
It was recently shown that there is a predominance of phase 1 introns near the cleavage site of signal peptides encoded by human genes. It was suggested that this biased distribution was due to intron insertion at AGmid R:G proto-splice sites. However, we found that there is no disproportional excess of AGmid R:G that would support insertion at proto-splice sites. In fact, all nGmid R:G sites are enriched in the vicinity of the cleavage site. Additional analyses support an alternative scenario in which exon-shuffling is largely responsible for such excess of phase 1 introns. 相似文献
45.
Wolf S Williamson WM Hewitt J Rivera-Aban M Lin S Ball A Scholes P Greening GE 《Applied and environmental microbiology》2007,73(17):5464-5470
46.
Dominant Microbial Populations in Limestone-Corroding Stream Biofilms, Frasassi Cave System, Italy 总被引:1,自引:2,他引:1 下载免费PDF全文
Jennifer L. Macalady Ezra H. Lyon Bess Koffman Lindsey K. Albertson Katja Meyer Sandro Galdenzi Sandro Mariani 《Applied microbiology》2006,72(8):5596-5609
Waters from an extensive sulfide-rich aquifer emerge in the Frasassi cave system, where they mix with oxygen-rich percolating water and cave air over a large surface area. The actively forming cave complex hosts a microbial community, including conspicuous white biofilms coating surfaces in cave streams, that is isolated from surface sources of C and N. Two distinct biofilm morphologies were observed in the streams over a 4-year period. Bacterial 16S rDNA libraries were constructed from samples of each biofilm type collected from Grotta Sulfurea in 2002. β-, γ-, δ-, and -proteobacteria in sulfur-cycling clades accounted for ≥75% of clones in both biofilms. Sulfate-reducing and sulfur-disproportionating δ-proteobacterial sequences in the clone libraries were abundant and diverse (34% of phylotypes). Biofilm samples of both types were later collected at the same location and at an additional sample site in Ramo Sulfureo and examined, using fluorescence in situ hybridization (FISH). The biomass of all six stream biofilms was dominated by filamentous γ-proteobacteria with Beggiatoa-like and/or Thiothrix-like cells containing abundant sulfur inclusions. The biomass of -proteobacteria detected using FISH was consistently small, ranging from 0 to less than 15% of the total biomass. Our results suggest that S cycling within the stream biofilms is an important feature of the cave biogeochemistry. Such cycling represents positive biological feedback to sulfuric acid speleogenesis and related processes that create subsurface porosity in carbonate rocks. 相似文献
47.
48.
Marina Giuliano Mauro Andreotti Giuseppe Liotta Haswell Jere Jean-Baptiste Sagno Martin Maulidi Sandro Mancinelli Ersilia Buonomo Paola Scarcella Maria F. Pirillo Roberta Amici Susanna Ceffa Stefano Vella Leonardo Palombi Maria Cristina Marazzi 《PloS one》2013,8(7)
Background
Optimized preventive strategies are needed to reach the objective of eliminating pediatric AIDS. This study aimed to define the determinants of residual HIV transmission in the context of maternal antiretroviral therapy (ART) administration to pregnant women, to assess infant safety of this strategy, and to evaluate its impact on maternal disease.Methodology/Principal Findings
A total of 311 HIV-infected pregnant women were enrolled in Malawi in an observational study and received a nevirapine-based regimen from week 25 of gestation until 6 months after delivery (end of breastfeeding period) if their CD4+ count was > 350/mm3 at baseline (n = 147), or indefinitely if they met the criteria for treatment (n. 164). Mother/child pairs were followed until 2 years after delivery. The Kaplan-Meier method was used to estimate HIV transmission, maternal disease progression, and survival at 24 months. The rate of HIV infant infection was 3.2% [95% confidence intervals (CI) 1.0-5.4]. Six of the 8 transmissions occurred among mothers with baseline CD4+ count > 350/mm3. HIV-free survival of children was 85.8% (95% CI 81.4-90.1). Children born to mothers with baseline CD4+ count < 350/mm3 were at increased risk of death (hazard ratio 2.6, 95% CI 1.1-6.1). Among women who had stopped treatment the risk of progression to CD4+ count < 350/mm3 was 20.6% (95% CI 9.2-31.9) by 18 months of drug discontinuation.Conclusions
HIV transmission in this cohort was rare however, it occurred in a significative proportion among women with high CD4+ counts. Strategies to improve treatment adherence should be implemented to further reduce HIV transmission. Mortality in the uninfected exposed children was the major determinant of HIV-free survival and was associated to maternal disease stage. Given the considerable proportion of women reaching the criteria for treatment within 18 months of drug discontinuation, life-long ART administration to HIV-infected women should be considered. 相似文献49.