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Determinar a evaporação é uma necessidade cada vez mais presente no cotidiano do agricultor, principalmente em zonas de clima árido e semi-árido. Entretanto, nem sempre é possível determiná-la devido aos custos e a operacionalidade dos equipamentos envolvidos. Uma forma barata e de fácil aplicação é estimar a evaporação a parti do nível do lençol freático. Há diversos modelos matemáticos para esse fim, porém é necessário uma calibragem para sua correta aplicação. Desta forma, o objetivo deste trabalho foi calibrar os modelos de Philip (1957), Harbaugh (1988), Moreal-Seytoux (1989) e Grilli & Vidal(1986), para estimar a evaporação em função do nível do lençol freático, utilizando a metodologia de Hargreaves, que é de fácil aplicação. Para a otimização na calibragem utilizou-se uma função–objeto e para uma análise estatística utilizou-se parâmetros como o erro quadrado médio, o coeficiente de massa residual e a razão dos desvios. Os quatro modelos apresentaram uma semelhança quanto aos seus resultados durante o período analisado. Para o período sem chuvas, os modelos de Harbaugh e de Philip apresentaram melhores resultados. Para o período chuvoso, os melhores desempenhos foram obtidos pelos modelos de Morel-Seytoux e de Philip.

Sarcoidosis is a granulomatous disease that can potentially involve all body tissues, including the liver in about 10-20% of cases (1-4). High quality data on the management of hepatic sarcoidosis (HS) are scarce. In absence of national and international guidelines, management of HS is still experienced-based. This survey was carried out amongst Italian hepatologists to describe their practices in the management of patients with HS. 1985 questionnaires were forwarded, of which 37 were completed and returned. Thirty-three centers reported managing patients with HS, 17 (51%) of these reported managing more than one patient. Twenty-seven (81%) centers obtained the diagnosis by liver biopsy, the remaining centers by radiological techniques or biopsy in other sites. In coexistence with HS, the pulmonary sarcoidosis was reported from 18 (54%) centers, while patients with no other localization, except for the hepatic one, were followed up in 6 (18%) centers. Twenty-two (66%) centers treated such patients with first-line steroid therapy, the remainders reported using other drugs. Finally, 3 (9%) centers reported the presence of transplant patients, other 3 (9%) centers of deceased patients. HS is a rare entity in Italy and there is a wide variation in diagnostics and therapeutics. A multicentric, prospective, national cohort study is needed to study this disease. [ABSTRACT FROM AUTHOR]

Cholangiocarcinoma (CCA) is an aggressive cancer with high resistance to chemotherapeutics. CCA is enriched in cancer stem cells, which correlate with aggressiveness and prognosis. FXR, a member of the metabolic nuclear receptor family, is markedly down-regulated in human CCA. Our aim was to evaluate, in primary cultures of human intrahepatic CCA (iCCA), the effects of the FXR agonist obeticholic acid (OCA), a semisynthetic bile acid derivative, on their cancerogenic potential. Primary human iCCA cell cultures were prepared from surgical specimens of mucinous or mixed iCCA subtypes. Increasing concentrations (0–2.5 μM) of OCA were added to culture media and, after 3–10 days, effects on proliferation (MTS assay, cell population doubling time), apoptosis (annexin V-FITC/propidium iodide), cell migration and invasion (wound healing response and Matrigel invasion assay), and cancerogenic potential (spheroid formation, clonogenic assay, colony formation capacity) were evaluated. Results: FXR gene expression was downregulated (RT-qPCR) in iCCA cells vs normal human biliary tree stem cells (p < 0.05) and in mucinous iCCA vs mixed iCCA cells (p < 0.05) but was upregulated by addition of OCA. OCA significantly (p < 0.05) inhibited proliferation of both mucinous and mixed iCCA cells, starting at a concentration as low as 0.05 μM. Also, CDCA (but not UDCA) inhibited cell proliferation, although to a much lower extent than OCA, consistent with its different affinity for FXR. OCA significantly induced apoptosis of both iCCA subtypes and decreased their in vitro cancerogenic potential, as evaluated by impairment of colony and spheroid formation capacity and delayed wound healing and Matrigel invasion. In general, these effects were more evident in mixed than mucinous iCCA cells. When tested together with Gemcitabine and Cisplatin, OCA potentiated the anti-proliferative and pro-apoptotic effects of these chemotherapeutics, but mainly in mixed iCCA cells. OCA abolished the capacity of both mucinous and mixed iCCA cells to form colonies when administered together with Gemcitabine and Cisplatin. In subcutaneous xenografts of mixed iCCA cells, OCA alone or combined with Gemcitabine or Cisplatin markedly reduced the tumor size after 5 weeks of treatment by inducing necrosis of tumor mass and inhibiting cell proliferation. In conclusion, FXR is down-regulated in iCCA cells, and its activation by OCA results in anti-cancerogenic effects against mucinous and mixed iCCA cells, both in vitro and in vivo. The effects of OCA predominated in mixed iCCA cells, consistent with the lower aggressiveness and the higher FXR expression in this CCA subtype. These results, showing the FXR-mediated capacity of OCA to inhibit cholangiocarcinogenesis, represent the basis for testing OCA in clinical trials of CCA patients. [ABSTRACT FROM AUTHOR]

An investigation was conducted in order to determine the effect of both the metallic transfer mode (pulsed arc or short circuit) and the O2 content in the Ar/O2 gas mixture, of the gas-metal arc welding process (GMAW), on the fatigue life under uniaxial conditions of welded joints of 316L stainless steel. It was concluded that the mixture of the shielding gases employed in the process could have an important influence on the fatigue life of the welded joints of such steel in two different ways. Firstly, through the modification of the radius of curvature at the joint between the welding toe and the base metal and, secondly, through a more pronounced degree of oxidation of the alloying elements induced by a higher O2 content in the mixture. As far as the metallic transfer mode is concerned, it has been determined that the welded joints obtained under a pulsed arc mode show a greater fatigue life in comparison with the joints obtained under short circuit for both gas mixtures. [ABSTRACT FROM AUTHOR]

Abstract: Hepatic progenitor cells are bi-potential stem cells residing in human and animal livers that are able to differentiate towards the hepatocytic and the cholangiocytic lineages. In adult livers, hepatic progenitor cells are quiescent stem cells with a low proliferating rate, representing a reserve compartment that is activated only when the mature epithelial cells of the liver are continuously damaged or inhibited in their replication, or in cases of severe cell loss. Hepatic progenitor cell activation has been described in various acute and chronic liver diseases. Their niche is composed by numerous cells such as Hepatic Stellate Cells, endothelial cells, hepatocytes, cholangiocytes, Kupffer cells, pit cells and inflammatory cells. All these cells, numerous hormones and growth factors could interact and cross-talk with progenitor cells influencing their proliferative and differentiative processes. Hepatic progenitor cells and their niche could represent, in the near future, a target for therapeutic approaches to liver disease based on cell-specific drug delivery systems. Isolation and transplantation of hepatic progenitor cells could represent a new approach for therapy of end-stage chronic liver diseases, as they offer many advantages to transplantation of mature hepatocytes. The possibility of applying stem cell therapy to liver diseases will represent a major goal in this field. [Copyright &y& Elsevier]

The Helicobacter pylori (H. pylori) cure rate following standard triple therapies is decreasing worldwide. Therefore, further approaches aimed to improve standard triple therapy efficacy should be attempted. This prospective, pilot study aimed to evaluate the therapeutic role of either Lactobacillus reuteri (L. reuteri) or a high concentration of probiotics in addition to standard triple therapies for H. pylori eradication. The study enrolled 65 consecutive dyspeptic patients with H. pylori infection. All patients underwent upper endoscopy with gastric biopsies. Patients were assigned to receive one of the following therapies: (a) standard 7-day triple; (b) the same 7-day triple therapy plus L. reuteri supplementation; (c) the same 7-day triple therapy plus a probiotic mixture; and d) a 14-day standard triple therapy plus a probiotic mixture. H. pylori eradication was checked by using a 13C-urea breath test performed 4-6 weeks after treatment. No therapy regimen achieved > 80% eradication rate at both intention-to-treat (ITT) and per protocol (PP) analyses. Although the 14-day therapy plus a probiotic mixture tended to achieve higher eradication rate (71%), no statistically significant difference emerged among the different therapy regimens tested (range: 53-71%). The lowest incidence of side-effects was observed following the 7-day therapy plus L. reuteri (6%) and highest with the 14-day triple therapy plus probiotic mixture (33%), although the difference failed to reach the statistically significance. In conclusion, our data found that 7-14 days triple therapy with or without probiotic supplementation failed to achieved acceptable H. pylori eradication rates. [ABSTRACT FROM AUTHOR]