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991.
A. Dalla Marta D. Grifoni T. Torrigiani Malaspina L. Cecchi F. Barbano M. Mancini S. Orlandini 《Aerobiologia》2011,27(3):213-220
This research was performed for the purpose of analysing the relationships between large-scale meteorological information,
in particular the North Atlantic Oscillation (NAO) index and the Sea Surface Temperature (SST), and the timing and magnitude
of the Cupressaceae pollen season in the Pistoia district of Central Italy. The results demonstrated that in specific periods of the year, the
NAO index, by partially determining the distribution of the main meteorological variables over the study area, is negatively
correlated with the start and the end, as well as the peak day of pollen concentration. Pollen data were also correlated with
the SST of the North Atlantic Ocean east of the Azores for the September–December period of the previous year, which is significant
for exploring possibilities in terms of predicting the timing and magnitude of the cypress pollen season. The analysis of
such meteorological variables and indices could be used to improve the existing forecasting systems of the phenology of the
cypress pollen season. Moreover, the possibility of using meteorological information freely available on internet could cut
costs and reduce spatial and temporal representativeness limitations relating to weather monitoring in loco. 相似文献
992.
Sertoli cells provide the microenvironment necessary for germ cell development and spermatogenesis; disruption of Sertoli cell morphology or function can lead to germ cell aplasia, which is observed in testicular dysgenesis syndrome. Mutation of the adenomatous polyposis coli (APC) gene has been associated with various human cancers, including testicular cancer, but its involvement in nonmalignant testicular pathologies has not been reported. We have developed a mouse model (APC(cko)) that expresses a truncated form of APC in Sertoli cells. Despite normal embryonic and early postnatal testicular development in APC(cko) mice, premature germ cell loss and Sertoli cell-only seminiferous tubules were observed in mutant testes without affecting Sertoli cell quiescence, apoptosis, or differentiation, which were confirmed by the absence of both proliferating cell nuclear antigen, DNA strand breaks, and anti-Müllerian hormone, respectively. We show that mutant Sertoli cells lose their apical extensions, which would normally enclose germ cells during various stages of spermatogenesis, and were unable to maintain the blood-testis barrier because of disrupted expression of junctional proteins. We also observed an up-regulation of Snail and Slug, markers suggestive of epithelial-mesenchymal transition in the Sertoli cells, but tumorigenesis was not observed. No comparable phenotype was observed with Sertoli cell-specific loss-of-function mutations in β-catenin, leading us to speculate that truncation of APC in Sertoli cells results in progressive degeneration of the seminiferous tubules by a mechanism that disrupts the integrity of Sertoli cell junctions independently of APC-regulated β-catenin activities and leads to development of a Sertoli cell-only phenotype. 相似文献
993.
Gauthier JY Belley M Deschênes D Fournier JF Gagné S Gareau Y Hamel M Hénault M Hyjazie H Kargman S Lavallée G Levesque JF Li L Mamane Y Mancini J Morin N Mulrooney E Robichaud J Thérien M Tranmer G Wang Z Wu J Black WC 《Bioorganic & medicinal chemistry letters》2011,21(10):2836-2839
A weak, UDP-competitive antagonist of the pyrimidinergic receptor P2RY14 with a naphthoic acid core was identified through high-throughput screening. Optimization provided compounds with improved potency but poor pharmacokinetics. Acylglucuronidation was determined to be the major route of metabolism. Increasing the electron-withdrawing nature of the substituents markedly reduced glucuronidation and improved the pharmacokinetic profile. Additional optimization led to the identification of compound 38 which is an 8 nM UDP-competitive antagonist of P2Y14 with a good pharmacokinetic profile. 相似文献
994.
Yu Z Bekker M Tramonti A Cook GM van Ulsen P Scheffers DJ de Mattos JT De Biase D Luirink J 《Journal of bacteriology》2011,193(6):1308-1316
The function of the essential inner membrane protein (IMP) YidC in Escherichia coli has been studied for a limited number of model IMPs and primarily using targeted approaches. These studies suggested that YidC acts at the level of insertion, folding, and quality control of IMPs, both in the context of the Sec translocon and as a separate entity. To further our understanding of YidC's role in IMP biogenesis, we screened a random overexpression library for factors that rescued the growth of cells upon YidC depletion. We found that the overexpression of the GadX and GadY regulators of the glutamate-dependent acid resistance system complemented the growth defect of YidC-depleted cells. Evidence is presented that GadXY overexpression counteracts the deleterious effects of YidC depletion on at least two fronts. First, GadXY prepares the cells for the decrease in respiratory capacity upon the depletion of YidC. Most likely, GadXY-regulated processes reduce the drop in proton-motive force that impairs the fitness of YidC-depleted cells. Second, in GadXY-overproducing cells increased levels of the general chaperone GroEL cofractionate with the inner membranes, which may help to keep newly synthesized inner membrane proteins in an insertion-competent state when YidC levels are limiting. 相似文献
995.
Cerdeira LT Schneider MP Pinto AC de Almeida SS dos Santos AR Barbosa EG Ali A Aburjaile FF de Abreu VA Guimarães LC Soares Sde C Dorella FA Rocha FS Bol E Gomes de Sá PH Lopes TS Barbosa MS Carneiro AR Jucá Ramos RT Coimbra NA Lima AR Barh D Jain N Tiwari S Raja R Zambare V Ghosh P Trost E Tauch A Miyoshi A Azevedo V Silva A 《Journal of bacteriology》2011,193(24):7025-7026
In this work, we report the whole-genome sequence of Corynebacterium pseudotuberculosis bv. equi strain CIP 52.97 (Collection Institut Pasteur), isolated in 1952 from a case of ulcerative lymphangitis in a Kenyan horse, which has evidently caused significant losses to agribusiness. Therefore, obtaining this genome will allow the detection of important targets for postgenomic studies, with the aim of minimizing problems caused by this microorganism. 相似文献
996.
Farias ME Revale S Mancini E Ordoñez O Turjanski A Cortez N Vazquez MP 《Journal of bacteriology》2011,193(14):3686-3687
The high-altitude Andean lakes (HAAL) in the Argentinean Puna-high Andes region represent an almost unexplored ecosystem exposed to extreme conditions (high UV irradiation, hypersalinity, drastic temperature changes, desiccation, and high pH). Here we present the first genome sequence, a Sphingomonas sp., isolated from this extreme environment. 相似文献
997.
Diego Oliveira Teixeira Herlon Victor Rodrigues Silva Bruna Farias Brito Brenna de Sousa Barbosa Beatriz Evaristo de Almeida Tabosa Lúcia Daniel Machado da Silva 《Animal Reproduction》2022,19(3)
Morphological sperm evaluation supported by the morphometry can be used in the determination of the seminal quality and in the investigation of potential extenders. Although there are studies comparing TRIS and ACP extenders, there are no comparative studies between them for the computerized assisted semen analysis (CASA), sperm viability, membrane functionality and sperm morphometry parameters of cryopreserved canine semen. Hence, we aimed to evaluate the effects of ACP-106c and TRIS on post-freezing canine sperm quality. Five dogs were submitted to semen collection twice with one-week interval. The semen was evaluated within the parameters: total motility, vigor, concentration, viability, plasma membrane functionality, morphology and morphometry. In the morphometric evaluation, the morphologically normal sperm was measured as: length, width, area and perimeter of the head and the midpiece, tail length and total length. The parameters of ellipticity, elongation, regularity and roughness were determined. Then, the semen was divided into two aliquots that were diluted in TRIS or ACP-106c, with the addition of egg yolk and glycerol. The diluted semen was refrigerated and frozen. The thawed samples were evaluated. Total motility, viability, sperm membrane functionality and normal morphology reduced after thawing in both extenders (morphology reduced from 89.60 ± 1.3% to 84.40 ± 1.8 and 84.60 ± 1.1% in TRIS and ACP-106c, respectively). However, it did not differ between TRIS and ACP-106c. In the ACP-106c the sperm head defects in cryopreserved semen were higher compared to fresh semen (P < 0.05). For all the morphometric parameters evaluated, there were no differences between fresh and cryopreserved samples (3.70 ± 0.4% vs. 2.30 ± 0.5%). In kinetics, with an interval of one week statistical differences between the extenders were found only in the parameters ALH and LIN (P < 0.05). Regardless of the extender, there were no changes in the morphometric parameters of sperm after thawing. 相似文献
998.
Julia M. Pescarini Moreno Rodrigues Enny S. Paixo Luciana Cardim Carlos A. A. de Brito Maria da Conceio N. Costa Andreia C. Santos Liam Smeeth Maria da Glria Teixeira Andr P. F. de Souza Mauricio L. Barreto Elizabeth B. Brickley 《PLoS neglected tropical diseases》2022,16(7)
BackgroundIn addition to their direct pathogenic effects, arthropod-borne (arboviruses) have been hypothesized to indirectly contribute to hospitalizations and death through decompensation of pre-existing comorbidities. Using nationwide data routinely collected from 1 January 2014 to 31 December 2019 in Brazil, we investigated whether local increases in arbovirus notifications were associated with excess hospitalization.MethodsWe estimated the relative risks for the association between municipality- and state-level increases in arboviral case notifications and age-standardized hospitalization rates (i.e., classified as direct or indirect based on ICD-10 codes) using Bayesian multilevel models with random effects accounting for temporal and geographic correlations. For municipality-level analyses, we excluded municipalities with <200 notifications of a given arbovirus and further adjusted the models for the local Gini Index, Human Development Index, and Family Healthcare Strategy (Estratégia de Saúde da Família) coverage. Models for dengue, Zika, and chikungunya were performed separately.ResultsFrom 2014 to 2019, Brazil registered 7,566,330 confirmed dengue cases, 159,029 confirmed ZIKV cases, and 433,887 confirmed CHIKV cases. Dengue notifications have an endemic and seasonal pattern, with cases present in 5334 of the 5570 (95.8%) Brazilian municipalities and most (69.5%) registered between February and May. Chikungunya notifications followed a similar seasonal pattern to DENV but with a smaller incidence and were restricted to 4390 (78.8%) municipalities. ZIKV was only notified in 2581 (46.3%) municipalities. Increases in dengue and chikungunya notifications were associated with small increases in age-standardized arbovirus-related hospitalizations, but no consistent association was found with all-cause or other specific indirect causes of hospitalization. Zika was associated to increases in hospitalizations by neurological diseases.ConclusionsAlthough we found no clear association between increased incidence of the three arboviruses and excess risks of all-cause or indirect hospitalizations at the municipality- and state-levels, follow-up investigations at the individual-level are warranted to define any potential role of acute arbovirus infection in exacerbating risks of hospitalization from underlying conditions. 相似文献
999.
The use of inexpensive biosorbents to sequester heavy metals from aqueous solutions, is one of the most promising technologies being developed to remove these toxic contaminants from wastewaters. Considering this challenge, the viability of Cr(III) and Pb(II) removal from aqueous solutions using a flocculating brewer's yeast residual biomass from a Portuguese brewing industry was studied. The influence of physicochemical factors such as medium pH, biomass concentration and the presence of a co-ion was characterised. Metal uptake kinetics and equilibrium were also analysed, considering different incubation temperatures. For both metals, uptake increased with medium pH, being maximal at 5.0. Optimal biomass concentration for the biosorption process was determined to be 4.5?g dry weight/l. In chromium and lead mixture solutions, competition for yeast binding sites was observed between the two metals, this competition being pH dependent. Yeast biomass showed higher selectivity and uptake capacity to lead. Chromium uptake kinetic was characterised as having a rapid initial step, followed by a slower one. Langmuir model describes well chromium uptake equilibrium. Lead uptake kinetics suggested the presence of mechanisms other than biosorption, possibly including its precipitation. 相似文献
1000.
Gustavo N. Marta Fernando F. de Arruda Fabiana A. Miranda Alice R.N.S. Silva Wellington F.P. Neves-Junior Anselmo Mancini Samir A. Hanna Carlos E.C.V. Abreu Joo Luis F. da Silva Jose Eduardo V. Nascimento Cecília Maria K. Haddad Fabio Y. Moraes Rafael Gadia 《Reports of Practical Oncology and Radiotherapy》2021,26(5):756
BackgroundThis study aims to assess the clinical outcomes of patients with spine metastases who underwent stereotactic ablative radiation therapy (SABR) as part of their treatment. SABR has arisen as a contemporary treatment option for spinal metastasis patients with good prognoses.Materials and methodsBetween November 2010 and September 2018, Spinal SABR was performed in patients with metastatic disease in different settings: radical (SABR only), postoperative (after decompression and/or fixation surgery), and reirradiation. Local control (LC), pain control, overall survival (OS) and toxicities were reported.ResultsEighty-five patients (corresponding to 96 treatments) with spine metastases were included. The median age was 59 years (range, 23–91). In most SA BR (82.3%, n = 79) was performed as the first local spine treatment, while in 12 settings (12.5%), fixation and/or decompression surgery was performed prior to SABR. Two-year overall survival rate was 74.1%, and median survival was 19 months. The LC rate at 2 years was 72.3%. With regard to pain control, among 67 patients presenting with pain before SA BR, 83.3% had a complete response, 12.1% had a partial response, and 4.6% had progression. Vertebral compression fractures occurred in 10 patients (11.7%), of which 5 cases occurred in the reirradiation setting. Radiculopathy and myelopathy were not observed. No grade III or IV toxicities were seen.ConclusionThis is the first study presenting a Brazilian experience with spinal SA BR, and the results confirm its feasibility and safety. SABR was shown to produce good local and pain control rates with low rates of adverse events. 相似文献