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101.
José Leopoldo Ferreira Antunes Tatiana Natasha Toporcov Maria Gabriela Haye Biazevic Antonio Fernando Boing Crispian Scully Stefano Petti 《PloS one》2013,8(7)
Alcohol drinking and tobacco smoking are assumed to have significant independent and joint effects on oral cancer (OC) development. This assumption is based on consistent reports from observational studies, which, however, overestimated the independent effects of smoking and drinking, because they did not account for the interaction effect in multivariable analyses. This case-control study sought to investigate the independent and the joint effects of smoking and drinking on OC in a homogeneous sample of adults. Case patients (N = 1,144) were affected by invasive oral/oropharyngeal squamous cell carcinoma confirmed histologically, diagnosed between 1998 and 2008 in four hospitals of São Paulo (Brazil). Control patients (N = 1,661) were not affected by drinking-, smoking-associated diseases, cancers, upper aero-digestive tract diseases. Cumulative tobacco and alcohol consumptions were assessed anamnestically. Patients were categorized into never/ever users and never/level-1/level-2 users, according to the median consumption level in controls. The effects of smoking and drinking on OC adjusted for age, gender, schooling level were assessed using logistic regression analysis; Model-1 did not account for the smoking-drinking interaction; Model-2 accounted for this interaction and included the resultant interaction terms. The models were compared using the likelihood ratio test. According to Model-1, the adjusted odds ratios (ORs) for smoking, drinking, smoking-drinking were 3.50 (95% confidence interval –95CI, 2.76–4.44), 3.60 (95CI, 2.86–4.53), 12.60 (95CI, 7.89–20.13), respectively. According to Model-2 these figures were 1.41 (95CI, 1.02–1.96), 0.78 (95CI, 0.48–1.27), 8.16 (95CI, 2.09–31.78). Analogous results were obtained using three levels of exposure to smoking and drinking. Model-2 showed statistically significant better goodness-of-fit statistics than Model-1. Drinking was not independently associated with OC, while the independent effect of smoking was lower than expected, suggesting that observational studies should be revised adequately accounting for the smoking-drinking interaction. OC control policies should focus on addictive behaviours rather than on single lifestyle risk factors. 相似文献
102.
Human Hemorrhagic Pulmonary Leptospirosis: Pathological Findings and Pathophysiological Correlations
Thales De Brito Vera Demarchi Aiello Luis Fernando Ferraz da Silva Ana Maria Gon?alves da Silva Wellington Luiz Ferreira da Silva Jussara Bianchi Castelli Antonio Carlos Seguro 《PloS one》2013,8(8)
Background
Leptospirosis is a re-emerging zoonosis with protean clinical manifestations. Recently, the importance of pulmonary hemorrhage as a lethal complication of this disease has been recognized. In the present study, five human necropsies of leptospirosis (Weil‘s syndrome) with extensive pulmonary manifestations were analysed, and the antibodies expressed in blood vessels and cells involved in ion and water transport were used, seeking to better understand the pathophysiology of the lung injury associated with this disease.Principal Findings
Prominent vascular damage was present in the lung microcirculation, with decreased CD34 and preserved aquaporin 1 expression. At the periphery and even inside the extensive areas of edema and intraalveolar hemorrhage, enlarged, apparently hypertrophic type I pneumocytes (PI) were detected and interpreted as a non-specific attempt of clearence of the intraalveolar fluid, in which ionic transport, particularly of sodium, plays a predominant role, as suggested by the apparently increased ENaC and aquaporin 5 expression. Connexin 43 was present in most pneumocytes, and in the cytoplasm of the more preserved endothelial cells. The number of type II pneumocytes (PII) was slightly decreased when compared to normal lungs and those of patients with septicemia from other causes, a fact that may contribute to the progressively low PI count, resulting in deficient restoration after damage to the alveolar epithelial integrity and, consequently, a poor outcome of the pulmonary edema and hemorrhage.Conclusions
Pathogenesis of lung injury in human leptospirosis was discussed, and the possibility of primary non-inflammatory vascular damage was considered, so far of undefinite etiopathogenesis, as the initial pathological manifestation of the disease. 相似文献103.
Elizabeth B. Oliveira-Sales Edgar Maquigussa Patricia Semedo Luciana G. Pereira Vanessa M. Ferreira Niels O. Camara Cassia T. Bergamaschi Ruy R. Campos Mirian A. Boim 《PloS one》2013,8(11)
Renovascular hypertension induced by 2 Kidney-1 Clip (2K-1C) is a renin-angiotensin-system (RAS)-dependent model, leading to renal vascular rarefaction and renal failure. RAS inhibitors are not able to reduce arterial pressure (AP) and/or preserve the renal function, and thus, alternative therapies are needed. Three weeks after left renal artery occlusion, fluorescently tagged mesenchymal stem cells (MSC) (2×105 cells/animal) were injected weekly into the tail vein in 2K-1C hypertensive rats. Flow cytometry showed labeled MSC in the cortex and medulla of the clipped kidney. MSC prevented a further increase in the AP, significantly reduced proteinuria and decreased sympathetic hyperactivity in 2K-1C rats. Renal function parameters were unchanged, except for an increase in urinary volume observed in 2K-1C rats, which was not corrected by MSC. The treatment improved the morphology and decreased the fibrotic areas in the clipped kidney and also significantly reduced renal vascular rarefaction typical of 2K-1C model. Expression levels of IL-1β, TNF-α angiotensinogen, ACE, and Ang II receptor AT1 were elevated, whereas AT2 levels were decreased in the medulla of the clipped kidney. MSC normalized these expression levels. In conclusion, MSC therapy in the 2K-1C model (i) prevented the progressive increase of AP, (ii) improved renal morphology and microvascular rarefaction, (iii) reduced fibrosis, proteinuria and inflammatory cytokines, (iv) suppressed the intrarenal RAS, iv) decreased sympathetic hyperactivity in anesthetized animals and v) MSC were detected at the CNS suggesting that the cells crossed the blood-brain barrier. This therapy may be a promising strategy to treat renovascular hypertension and its renal consequences in the near future. 相似文献
104.
da Silva-Carvalho Lidiane Maria Genovez-Oliveira Jhon Lennon de Souza Oliveira Mariana de Oliveira Águida Aparecida de Lima Viviane Moreira Ferreira Ildemar Berto Bruno Pereira 《Systematic parasitology》2020,97(6):847-855
Systematic Parasitology - Isospora parnaitatiaiensis Silva, Rodrigues, Lopes, Berto, Luz, Ferreira & Lopes, 2015 was identified from a new host, the plain antvireo Dysithamnus mentalis... 相似文献
105.
Luiz F. C. Tencatt Janice Muriel-Cunha Jansen Zuanon Marlon F. C. Ferreira Marcelo R. Britto 《Journal of fish biology》2020,97(4):1072-1086
Aspidoras azaghal n. sp. was discovered during a multitaxonomic scientific expedition to the remote Amazon Terra do Meio region in tributaries to the rio Xingu basin, Pará, Brazil. The new species can be promptly distinguished from its congeners by the following combination of features: (a) absence of the first dorsal-fin element; (b) parieto-supraoccipital fontanel located medially on bone; (c) absence of a longitudinal dark-brown or black stripe along flank midline; (d) ventral surface of trunk covered by clearly smaller, irregular and/or roundish platelets; (e) inner laminar expansion of infraorbital 1 well developed; (f) relatively wide frontal bone, with width equal to half of entire length; (g) absence of a thick, longitudinal conspicuous dark-brown stripe along dorsal portion of flank; and (h) poorly developed serrations on posterior margin of the pectoral-fin spine. Besides morphological evidence, the molecular analyses indicated significant differences between the new species and its congeners, with A. albater and A. raimundi as its closest species, showing 6.53% of genetic differentiation in both cases. The intraspecific molecular data revealed gene flow (peer fixation index, FST = 0.05249, P > 0.05, for the cytochrome oxidase I (COI) marker and FST = -0.01466, P > 0.05, for the control region) between specimens upstream and downstream from a 30-m height waterfall at the type-locality, which therefore represent a single population. Furthermore, it was possible to observe a unidirectional gene flow pattern, with genetic diversity increasing in the downstream direction. 相似文献
106.
107.
Bezagio Renata Coltro Colli Cristiane Maria Romera Liara Izabela Lopes de Almeida Caroline Rodrigues Ferreira Érika Cristina Mattia Salete Gomes Mônica Lúcia 《Molecular biology reports》2020,47(2):1233-1239
Molecular Biology Reports - Molecular detection of Giardia duodenalis by polymerase chain reaction (PCR) is difficult in faecal samples due to inhibitors that contaminate DNA preparations, or due... 相似文献
108.
Santos Brígida Delgadinho Mariana Ferreira Joana Germano Isabel Miranda Armandina Arez Ana Paula Faustino Paula Brito Miguel 《Molecular biology reports》2020,47(7):5397-5402
Molecular Biology Reports - The aim of this study was to explore the association between alpha-thalassemia, fetal hemoglobin, hematological indices, and clinical adverse events in Angolan sickle... 相似文献
109.
The fig (Ficus L.) infructescence, called syconium, is a receptacle with an apical opening, the ostiole, closed by bracts. The ostiolar bracts produce an exudate, which is rather conspicuous in some species. It has not been histochemically analyzed yet, and the structures responsible for its production are still unknown. Some wild growing species of Ficus from Brazil produce high amounts of this ostiolar exudate. Ficus enormis (Mart. ex Miq.) Miq. grows as trees or shrubs in the Atlantic rainforest. Our goal was to identify the secretory structures present in the inflorescence and, to characterize histochemically the ostiolar tissues and exudates. Syconia samples of F. enormis were processed and stained according to the usual techniques in plant anatomy. The morphological analysis revealed different types of bracts, one type specialized in secretion, another showing transitional characteristics between secretory and non-secreting bracts, and a third one being non-secreting. They are designated as secretory ostiolar bracts, transitional bracts and wall bracts. The floral bracteoles, digital-shaped colleters present in the ostiole, at the syconium axis and at the flower receptacle, were also analyzed. All have similar structure, like finger-shaped secretory trichomes. The colleters present among ostiolar bracts may contribute to production and composition of the ostiole exudate. 相似文献
110.
Susana Isabel Ferreira Luís Miguel Pires José Ferrão Joaquim Sá Armando Serra Isabel Marques Carreira 《Gene》2013
Fragile X syndrome is caused by the expansion of an unstable CGG repeat in the 5′UTR of FMR1 gene. The occurrence of mosaicism is not uncommon, especially in male patients, whereas in females it is not so often reported. Here we report a female foetus that was subject to prenatal diagnosis, because of her mother being a premutation carrier. The foetus was identified as being a mosaic for an intermediate allele and a full mutation of FMR1 gene, in the presence of a normal allele. The mosaic status was confirmed in three different tissues of the foetus – amniotic fluid, skin biopsy and blood – the last two obtained after pregnancy termination. Karyotype analysis and X-chromosome STR markers analysis do not support the mosaicism as inheritance of both maternal alleles. Oligonucleotide array-CGH excluded an imbalance that could contain the primer binding site with a different repeat size. The obtained results give compelling evidence for a postzygotic expansion mechanism where the foetus mosaic pattern originated from expansion of the mother's premutation into a full mutation and consequent regression to an intermediate allele in a proportion of cells. These events occurred in early embryogenesis before the commitment of cells into the different tissues, as the three tested tissues of the foetus have the same mosaic pattern. The couple has a son with Fragile X mental retardation syndrome and choose to terminate this pregnancy after genetic counselling. 相似文献