107 research outputs found
Estudo da Influência da Interação Solo-atmosfera nos Perfis de Umidade, Sucção e Temperatura de um Subsolo Não Saturado.
Este trabalho dedica-se à análise da influência da interação solo-atmosfera nos perfis de umidade, sucção e temperatura do perfil de um subsolo não saturado. Também é objeto de interesse neste estudo a análise da profundidade da zona ativa, região do solo influenciada pelas variações climáticas. Um modelo numérico de interface solo-atmosfera é utilizado para calcular a taxa de evaporação a partir do solo, e a equação de fluxo de massa (água lÃquida Lei de Darcy e vapor Lei de Fick) em conjunto com a equação de fluxo de calor (de Vries, 1987) são adotadas para determinar os perfis de temperatura, umidade e poro pressão do solo. Para as simulações numéricas é adotado um programa computacional unidimensional que utiliza o Método das Diferenças Finitas para resolver simultaneamente as equações diferencias parciais de fluxo de massa (água lÃquida e vapor) e calor. As análises realizadas utilizam dados climáticos coletados em Mormoiron, França, obtidos entre 2004 e 2005. Durante as análises, parâmetros foram alterados e dados climáticos simulados, sendo os resultados obtidos comparados com casos de referência. Dentre as conclusões do trabalho, pode-se citar: (a) a variação do perfil inicial de temperatura do solo (PIT) pode afetar os perfis de temperatura do solo, especialmente na região mais profunda onde as temperaturas se mantém praticamente estáveis ao longo de todo o ano; (b) o parâmetro Albedo pode afetar o perfil de temperatura do solo, especialmente na estação mais quente (grande radiação solar). Durante o inverno, valores albedo precisos não influenciam o teor de água no solo; (c) a zona ativa na região do estudo possui cerca de 1,5 m de profundidade. A partir dessa profundidade os perfis de temperatura, umidade e sucção do solo se mantém praticamente constantes ao longo do ano; (d) a utilização de médias para os inputs diários modifica a profundidade da zona ativa, sugerindo que sob condições adversas a profundidade da zona ativa de uma determinada região pode ser alterada; (e) a intensidade e a distribuição da precipitação afetam os perfis de umidade volumétrica e sucção do solo
Extensive solitary lymphatic malformation of the liver in a child: a case report and literature review
Intrabdominal lymphatic malformations are rare benign congenital vascular anomalies that account for less than 5% of benign masses in childhood, with an extremely variable clinical presentation. For this reason, although their radiological appearance is usually typical, diagnosis can be challenging and not always immediate. This report describes a unique case of extensive solitary hepatic lymphatic malformation in a 10-year-old boy with both extra- and intraparenchymal development with no associated symptoms. A literature review of reported cases of solitary hepatic lymphatic malformation is also included
Closing-Wedge Posterior Tibial Slope-Reducing Osteotomy in Complex Revision ACL Reconstruction
Background: A posterior tibial slope (PTS) >12° has been shown to correlate with failure of anterior cruciate ligament (ACL) reconstruction (ACLR). PTS-reducing osteotomy has been described to correct the PTS in patients with a deficient ACL, mostly after failure of primary ACLR. Purpose: To report radiologic indices, clinical outcomes, and postoperative complications after PTS-reducing osteotomy performed concurrently with revision ACLR (R-ACLR). Study design: Case series; Level of evidence, 4. Methods: A review of medical records at 3 institutions was performed of patients who had undergone PTS-reducing osteotomy concurrently with R-ACLR between August 2010 and October 2020. Radiologic parameters recorded included the PTS, patellar height according to the Caton-Deschamps Index (CDI), and anterior tibial translation (ATT). Patient-reported outcomes (International Knee Documentation Committee [IKDC] and Knee injury and Osteoarthritis Outcome Score [KOOS]), reoperations, and complications were evaluated. Results: Included were 23 patients with a mean follow-up of 26.7 months (range, 6-84 months; median, 22.5 months). Statistically significant differences from preoperative to postoperative values were found in PTS (median [range], 14.0° [12°-18°] vs 4.0° [0°-15°], respectively; P < .001), CDI (median, 1.00 vs 1.10, respectively; P = .04) and ATT (median, 8.5 vs 3.6 mm, respectively; P = .001). At the final follow-up, the IKDC score was 52.4 ± 19.2 and the KOOS subscale scores were 81.5 ± 9.5 (Pain), 74 ± 21.6 (Symptoms), 88.5 ± 8 (Activities of Daily Living); 52.5 ± 21.6 (Sport and Recreation), and 48.8 ± 15.8 (Quality of Life). A traumatic ACL graft failure occurred in 2 patients (8.7%). Reoperations were necessary for 6 patients (26.1%) because of symptomatic hardware, and atraumatic recurrent knee instability was diagnosed in 1 patient (4.3%). Conclusion: Tibial slope-reducing osteotomy resulted in a significant decrease of ATT and can be considered in patients with a preoperative PTS ≥12° and ≥1 ACLR failure. In highly complex patients with multiple prior surgeries, the authors found a reasonably low graft failure rate (8.7%) when utilizing PTS-reducing osteotomy. Surgeons must be aware of potential complications in patients with multiple previous failed ACLRs
Estudo de seguimento por dois anos de idosos residentes em São Paulo, Brasil: metodologia e resultados preliminares
INTRODUCTION: Previous cross-sectional studies have shown a high prevalence of chronic disease and disability among the elderly. Given Brazil s rapid aging process and the obvious consequences of the growing number of old people with chronic diseases and associated disabilities for the provision of health services, a need was felt for a study that would overcome the limitations of cross-sectional data and shed some light on the main factors determining whether a person will live longer and free of disabling diseases, the so-called successful aging. The methodology of the first follow-up study of elderly residents in Brazil is presented. METHOD: The profile of the initial cohort is compared with previous cross-sectional data and an in-depth analysis of nonresponse is carried out in order to assess the validity of future longitudinal analysis. The EPIDOSO ( Epidemiologia do Idoso ) Study conducted a two-year follow-up of 1,667 elderly people (65+), living in S. Paulo. The study consisted of two waves, each consisting of household, clinical, and biochemical surveys. RESULTS AND CONCLUSIONS: In general, the initial cohort showed a similar profile to previous cross-sectional samples in S. Paulo. There was a majority of women, mostly widows, living in multigenerational households, and a high prevalence of chronic illnesses, psychiatric disturbances, and physical disabilities. Despite all the difficulties inherent in follow-up studies, there was a fairly low rate of nonresponse to the household survey after two years, which did not actually affect the representation of the cohort at the final household assessment, making unbiased longitudinal analysis possible. Concerning the clinical and blood sampling surveys, the respondents tended to be younger and less disabled than the nonrespondents, limiting the use of the clinical and laboratory data to longitudinal analysis aimed at a healthier cohort. It is worth mentioning that gender, education, family support, and socioeconomic status were not important determinants of nonresponse, as is often the case.INTRODUÇÃO: Estudos transversais recentes mostraram alta prevalência de doenças crônicas e incapacidades fÃsicas entre idosos. Considerando o rápido processo de envelhecimento do Brasil e as conseqüências que esse aumento de idosos com doenças crônicas e incapacidades associadas acarretará para o sistema de saúde, fazia-se necessário estudo que pudesse superar as limitações dos dados transversais, permitindo determinar quais os fatores determinantes de uma vida longa e livre de doenças incapacitantes, o chamado envelhecimento bem sucedido. É apresentada a metodologia do primeiro estudo epidemiológico longitudinal com idosos residentes na comunidade, no Brasil. MÉTODO: O perfil do cohorte inicial é comparado com dados de estudos anteriores a com o perfil dos não respondentes para avaliar a validade de análises longitudinais futuras.O projeto EPIDOSO (Epidemiologia do Idoso) seguiu por dois anos 1.667 idosos (65+), residentes em São Paulo. Consistiu de duas ondas, cada qual com três inquéritos: domiciliar, clÃnico e laboratorial. RESULTADOS E CONCLUSÕES: O perfil da população não diferiu de estudos anteriores, mostrando maioria de mulheres, viúvas, vivendo em domicÃlios multigeracionais, com uma alta prevalência de doenças crônicas, distúrbios psiquiátricos e incapacidades fÃsicas. A despeito de todas as dificuldades inerentes a um estudo longitudinal, o grupo de não-respondentes ao segundo inquérito domiciliar não diferiu significativamente dos respondentes, assegurando análises longitudinais livres desse tipo de viés. Em relação aos inquéritos clÃnico e laboratorial, os não-respondentes mostraram-se mais velhos e mais incapacitados que os respondentes, limitando o uso dos dados clÃnicos e laboratoriais a análises pertinentes a uma cohorte mais jovem e saudável. Sexo, educação, apoio familiar e nÃvel socioeconômico não influenciaram de forma significativa a taxa de não - resposta, ao contrário do que se costuma verificar.Universidade Federal de São Paulo (UNIFESP)UNIFESPSciEL
GPER mediates the angiocrine actions induced by IGF1 through the HIF-1α/VEGF pathway in the breast tumor microenvironment
The G protein estrogen receptor GPER/GPR30 mediates estrogen action in breast cancer cells as well as in breast cancer-associated fibroblasts (CAFs), which are key components of microenvironment driving tumor progression. GPER is a transcriptional target of hypoxia inducible factor 1 alpha (HIF-1α) and activates VEGF expression and angiogenesis in hypoxic breast tumor microenvironment. Furthermore, IGF1/IGF1R signaling, which has angiogenic effects, has been shown to activate GPER in breast cancer cells. We analyzed gene expression data from published studies representing almost 5000 breast cancer patients to investigate whether GPER and IGF1 signaling establish an angiocrine gene signature in breast cancer patients. Next, we used GPER-positive but estrogen receptor (ER)-negative primary CAF cells derived from patient breast tumours and SKBR3 breast cancer cells to investigate the role of GPER in the regulation of VEGF expression and angiogenesis triggered by IGF1. We performed gene expression and promoter studies, western blotting and immunofluorescence analysis, gene silencing strategies and endothelial tube formation assays to evaluate the involvement of the HIF-1α/GPER/VEGF signaling in the biological responses to IGF1. We first determined that GPER is co-expressed with IGF1R and with the vessel marker CD34 in human breast tumors (n = 4972). Next, we determined that IGF1/IGF1R signaling engages the ERK1/2 and AKT transduction pathways to induce the expression of HIF-1α and its targets GPER and VEGF. We found that a functional cooperation between HIF-1α and GPER is essential for the transcriptional activation of VEGF induced by IGF1. Finally, using conditioned medium from CAFs and SKBR3 cells stimulated with IGF1, we established that HIF-1α and GPER are both required for VEGF-induced human vascular endothelial cell tube formation. These findings shed new light on the essential role played by GPER in IGF1/IGF1R signaling that induces breast tumor angiogenesis. Targeting the multifaceted interactions between cancer cells and tumor microenvironment involving both GPCRs and growth factor receptors has potential in future combination anticancer therapies
Impaired leukocyte influx in cervix of postterm women not responding to prostaglandin priming
<p>Abstract</p> <p>Background</p> <p>Prolonged pregnancies are associated with increased rate of maternal and fetal complications. Post term women could be divided into at least two subgroups, one where parturition is possible to induce by prostaglandins and one where it is not. Our aim was to study parameters in cervical biopsies in women with spontaneous delivery at term (controls) and compare to those that are successfully induced post term (responders), and those that are not induced (non-responders), by local prostaglandin treatment.</p> <p>Methods</p> <p>Stromal parameters examined in this study were the accumulation of leukocytes (CD45, CD68), mRNAs and/or proteins for the extracellular matrix degrading enzymes (matrix metalloproteinase (MMP)-2, MMP-8 and MMP-9), their inhibitors (tissue inhibitor of MMP (TIMP)-1 and TIMP-2), interleukin-8 (IL-8), the platelet activating factor-receptor (PAF-R), syndecan-1 and estrogen binding receptors (estrogen receptor (ER)α, ERβ and G-coupled protein receptor (GPR) 30) as well as the proliferation marker Ki-67.</p> <p>Results</p> <p>The influx of leukocytes as assessed by CD45 was strongest in the responders, thereafter in the controls and significantly lower in the non-responders. IL-8, PAF-R and MMP-9, all predominantly expressed in leukocytes, showed significantly reduced immunostaining in the group of non-responders, while ERα and GPR30 were more abundant in the non-responders, as compared to the controls.</p> <p>Conclusion</p> <p>The impaired leukocyte influx, as reflected by the reduced number of CD45 positive cells as well as decreased immunostaining of IL-8, PAF-R and MMP-9 in the non-responders, could be one explanation of the failed ripening of the cervix in post term women. If the decreased leukocyte influx is a primary explanation to absent ripening or secondary, as a result of other factors, is yet to be established.</p
Beneficial Effects of Estrogen in a Mouse Model of Cerebrovascular Insufficiency
BACKGROUND: The M(5) muscarinic acetylcholine receptor is known to play a crucial role in mediating acetylcholine dependent dilation of cerebral blood vessels. Previously, we reported that male M(5) muscarinic acetylcholine knockout mice (M5R(-/-) mice) suffer from a constitutive constriction of cerebral arteries, reduced cerebral blood flow, dendritic atrophy, and short-term memory loss, without necrosis and/or inflammation in the brain. METHODOLOGY/PRINCIPAL FINDINGS: We employed the Magnetic Resonance Angiography to study the area of the basilar artery in male and female M5R(-/-) mice. Here we show that female M5R(-/-) mice did not show the reduction in vascular area observed in male M5R(-/-) mice. However, ovariectomized female M5R(-/-) mice displayed phenotypic changes similar to male M5R(-/-) mice, strongly suggesting that estrogen plays a key role in the observed gender differences. We found that 17beta-estradiol (E2) induced nitric oxide release and ERK activation in a conditional immortalized mouse brain cerebrovascular endothelial cell line. Agonists of ERalpha, ERbeta, and GPR30 promoted ERK activation in this cell line. Moreover, in vivo magnetic resonance imaging studies showed that the cross section of the basilar artery was restored to normal in male M5R(-/-) mice treated with E2. Treatment with E2 also improved the performance of male M5R(-/-) mice in a cognitive test and reduced the atrophy of neural dendrites in the cerebral cortex and hippocampus. M5R(-/-) mice also showed astrocyte swelling in cortex and hippocampus using the three-dimensional reconstruction of electron microscope images. This phenotype was reversed by E2 treatment, similar to the observed deficits in dendrite morphology and the number of synapses. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that M5R(-/-) mice represent an excellent novel model system to study the beneficial effects of estrogen on cerebrovascular function and cognition. E2 may offer new therapeutic perspectives for the treatment of cerebrovascular insufficiency related memory dysfunction
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