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A common approach to interpret the ‘jet phenomenon’ observed in active galactic nuclei and young stellar objects is via magnetohydrodynamic models of collimated outflows magnetically driven from quasi-Keplerian accretion discs in the proximity of a central gravitational attractor. In this study we present a series of time-dependent axisymmetric numerical simulations of a jet-launching accretion disc, where the outflow and the disc itself are treated consistently. In particular, the issue of thermal effects due to anomalous transport coefficients is being addressed. When the radiative losses of the accretion disc cannot perfectly balance Ohmic and viscous heating, the latter can severely influence the mass loading process. Since the ejection rates determine to a great extent the dynamics of the outflowing plasma, disc thermodynamics should not be neglected. We investigate numerically the impact of heating–cooling effects in both outflow dynamics and accretion disc structure. A relationship is established between heating and various important parameters of the outflow (magnetic lever arm, ejection efficiency, mass flux, etc.) that is briefly discussed in connection with observational data. [ABSTRACT FROM AUTHOR]

Twenty-eight patients with radiolucent biliary duct stones without cholangitis and jaundice were randomly allocated into two treatment groups receiving ursodeoxycholic acid 12 mg/kg (group A) or placebo (group B) in three daily doses for 24 months. In group A stones disappeared completely in seven patients and partially in one; placebo administration had no effect on stone size and three patients of group B (only one of group A) went to surgery for complications. Ursodeoxycholic acid treatment did not adversely affect liver function tests, and alkaline phosphatase decreased. Abdominal and biliary colics also became less frequent in the first six months of therapy in group A, but not in the placebo group. The bile was supersaturated with cholesterol in both groups, but decreased significantly only in patients receiving ursodeoxycholic acid even though the lithogenic index remained high. Cholesterol saturation of bile does not seem to be the only factor determining the dissolution of biliary duct stones which sometimes contain cholesterol as the main component. [ABSTRACT FROM PUBLISHER]

Sulfur availability and the end products of its metabolism, cysteine, glutathione and phytochelatins, play an important role in heavy metal tolerance, chromium included. Sulfate and chromate not only compete for the transporters but also for assimilation enzymes and chromium tolerance in various organisms has been associated to differences in this pathway. We investigated the mechanisms of Cr(VI)-tolerance increase induced by S-starvation focusing on the role of ATP sulfurylase (ATS) in two strains of Scenedesmus acutus with different chromium sensitivity. S-starvation enhances the defence potential by increasing sulfate uptake/assimilation and decreasing chromium uptake, thus suggesting a change in the transport system. We isolated two isoforms of the enzyme, SaATS1 and SaATS2, with different sensitivity to sulfur availability, and analysed them in S-sufficient and S-replete condition both in standard and in chromium supplemented medium. SaATS2 expression is different in the two strains and presumably marks a different sulfur perception/exploitation in the Cr-tolerant. Its induction and silencing are compatible with a role in the transient tolerance increase induced by S-starvation. This enzyme can however hardly be responsible for the large cysteine production of the Cr-tolerant strain after starvation, suggesting that cytosolic rather than chloroplastic cysteine production is differently regulated in the two strains., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The gene expression of the wild type (S2-N) and a Cr-tolerant strain (S2-T) of the unicellular green alga Scenedesmus acutus has been compared in order to get more insight on their different chromium sensitivity. The RNA of the two strains was extracted after 4 days of culture in standard medium without chromium and analyzed by means of RNA differential display. The two strains showed differential gene transcription even in the absence of the heavy metal and six putatively differential amplicons were evidenced in the Cr-tolerant strain. Among the isolated amplicons, S2-T A63 was much more pronouncedly transcribed in the tolerant than in the wild type strain and was further characterized. S2-T A63 corresponding gene is present with the same copy number in the wild type and tolerant genomes and corresponds to an mRNA of about 2000 nt. The corresponding transcript is overexpressed in the Cr-tolerant strain after a 4-day culture and is not up-regulated by chromium exposure. The S2-T A63 sequence, obtained up to now, does not show significant homologies with any known gene. However, the analysis of the putative translation product reveals the presence of an interrupted fasciclin domain. This extracellular domain has been found in proteins from mammals, insects, echinoderms, plants, yeast and bacteria and is usually involved in cell adhesion. This finding suggests that the product for the S2-T A63 translation has an extracellular collocation, maybe as surface or secreted protein involved in external chromium detoxification.

A wild-type and a Cr-tolerant strain of the unicellular green alga Scenedesmus acutus were used to investigate if the difference in tolerance to Cr(VI) could depend on a different response to oxidative stress in terms of free cysteine (Cys) and reduced glutathione (GSH), and in preventing membrane lipid peroxidation. The growth of the two strains in standard medium in the presence of Cr(VI) 9.6, 19.2 or 38.4microM was compared, and the content of thiobarbituric acid reactive substances (TBARS) after a 4-day treatment was determined as marker of lipid peroxidation. The Cys and GSH contents were determined in both strains treated with Cr(VI) for 24h in HEPES buffer both enriched and not with sulphate. The treated algae were also subjected to recovery test in standard medium. The growth of wild type was inhibited at all Cr(VI) concentrations, while that of the Cr-tolerant strain only at the highest one. After exposure to 19.2microM Cr(VI), TBARS levels ranging from 0.091 to 0.263micromol/g d.w. were detected in the wild type, while only a slight increase (0.090+/-0.014micromol/g d.w.) was observed in the Cr-tolerant strain. Following treatment with 38.4microM Cr(VI), TBARS levels rose significantly and were similar in the two strains. The Cys content did not vary significantly in the cells exposed to Cr(VI) in either sulphate-lacking or sulphate-enriched buffer, and the differences between the two strains were insignificant. In the wild-type strain, the GSH content showed a significant downward trend with the increase in Cr(VI) concentration in the sulphate-lacking buffer, while it remained as high as the one of control cells in the sulphate-enriched buffer. In the Cr-tolerant strain, the GSH content did not vary significantly when the treatment took place in the sulphate-lacking buffer, while it showed a significant rise with the increase in Cr(VI) concentration in the sulphate-enriched buffer. The growth of both strains during recovery was significantly faster after treatment in the sulphate-enriched than in the sulphate-lacking buffer, the Cr-tolerant strain showing a much higher recovery capacity than the wild type. It appears that the Cr-tolerant strain, when exposed to Cr(VI) in the presence of a sulphur source, can increase GSH pool to levels not achievable by the wild type, and is thus able to recover better. This first report on the role of thiol compounds in Cr tolerance in algae suggests that tolerance to Cr(VI) in S. acutus could depend on a prompt up-regulation of the pathways leading to GSH synthesis.

Unlabelled: Few data exist on the medicoeconomic usefulness of PET in the management of metachronous liver metastases from colorectal cancer. This study was designed to assess the cost-effectiveness of PET in the diagnosis and staging of patients with metachronous liver metastases of colorectal cancer using a decision analysis model., Methods: Two alternatives were compared: CT and CT associated with PET (CT+PET). Transition probabilities were estimated from published data and consultations with experts. Survival data were provided by the Burgundy Digestive Cancer Registry (France). Costs of imaging techniques and treatments were assessed using reimbursements from the French health care insurance for the year 2004. Evaluation criteria included incremental cost-effectiveness ratios and the proportion of unnecessary operations avoided in patients without metachronous liver metastases., Results: CT+PET was the most cost-effective strategy, presenting an expected incremental cost saving of 2,671 (approximately $3,213) per patient, for the same level of expected effectiveness as CT alone (1.88-y life expectancy per patient). Sensitivity analyses performed on epidemiologic and economic parameters showed that this model was robust. The model also suggested that CT+PET could avoid exploratory surgery for 6.1% of patients-that is, 88.4% risk reduction compared with CT alone., Conclusion: PET for diagnosis and staging does not generate additional survival effectiveness compared with CT alone. However cost savings associated with its use and the improvement of therapeutic management therefore justify its generalization in clinical practice.

Many abiotic and biotic factors can influence the partitioning equilibrium of heavy metals, thus influencing metal impact on aquatic environments. Unicellular algal species release soluble organic substances able to complex metals. In our laboratory a Cr-tolerant strain was selected and isolated from a wild type strain of Scenedesmus acutus. The exudates released by the two strains counteracted the growth inhibition caused by Cr(VI) and the exudates of the Cr-tolerant strain were more effective. On the contrary, the exudates did not reduce chromium toxicity to the cladoceran Daphnia magna. The reduction of chromium effect on algae seems the consequence of an algae-specific interaction among Cr(VI), exudates and algal cells. Chromium uptake resulted to be energy-dependent since bioaccumulation rate in subdued light condition was lower than at high light intensity. The effect of Cr(VI) on algae changed depending on metabolism of the cells and in particular it seemed to be related to the bioaccumulation rate. Tolerance in the selected strain could not be ascribed to a lower uptake of chromium. The difference in sensitivity to chromium between the two strains was exploited to evaluate if tolerance acquired by algae could have consequences for Daphnia. After treatment with Cr(VI), the two strains of S. acutus were used as food source for D. magna. The results indicate that chromium is accumulated by algae in a form not available for daphnids and that Cr tolerance acquired by the algae can be of some advantage to the consumer organism.

The study compared electrical brain activity of 6 subjects in 5 different conditions. Absolute theta and alpha power in the frontal, parietal, and occipital areas were analyzed, with significant differences found only in the frontal area. Results suggested that the perception of movement requires higher order cognitive processing outside the occipital area. Implications for education and cognitive research are discussed.

The report of diverticulosis of right colon in a patient formerly operated on for perforation of caecum single ulcer appeared to the authors as a confirmation of a common etiology between both lesions. The single ulcer would probably represent a form of manifestation for the acute phlogosis of a diverticulum.

The expression of c-myb, c-myc, histone H3, and ornithine decarboxylase genes was examined by Northern blot analysis in the normal and neoplastic mucosa of ten subjects affected by colon cancer. The mRNA levels of c-myb protooncogene were detected at low levels in all normal samples but were increased in the neoplastic mucosa of six cases in comparison to the normal counterpart. In five of these six cases the mRNA levels of c-myc, histone H3, and ornithine decarboxylase mRNAs were also increased, suggesting that there is a relation between the high expression of c-myb and the fraction of cycling neoplastic cells.

8,738 cases of acute appendicitis, all operated on emergency, have been examined considering their total mortality (3 cases), and their post-operative complications (2.04%), secondary especially to the septic character of this disease. Diagnosis and treatment of acute appendicitis still require a particular attention and care.

A diagnostic assessment was made of 74 cases of non-penetrating abdominal wounds observed over the previous 5 years. Laparoscopy performed in 49 polytraumatised patients made a decisive contribution to accurate, early diagnosis, with an indication for emergency surgery in 35 cases (32 visceral lesions and 3 retroperitoneal haematoma), whereas it was clear from the negative finding that surgery was not required in the remaining 14. It is felt that all additional radiological and instrumental diagnostic should be employed, and that careful clinical examination and repeated inspection, preferably by the same surgeon, are important in cases of multiple injury, since the situation may become dramatically worse in the space of a few hours.

The authors study the diagnostical problems, especially those involved in the preoperative diagnosis of malignancy, of four cases of duodenal villous adenoma. A more frequent use of endoscopy can allow the observation of this lesion in early stage, such as to ensure recovery through an intervention as scarcely demolishing as possible. However, surgeons plotting the strategy of operation should bear in mind the potential malignancy of duodenal villous adenoma.

The authors report a case of acute necrotising enteritis occurring on the 7th day after total hysterectomy with bilateral removal of the adnexa for fibroids in a 45 year-old woman. This is the first case in the literature to occur after hysterectomy. The clinical picture included the onset of intestinal obstruction with severe general toxic manifestations. The diagnosis was made at operation and, in spite of intestinal resection, the patient died on the 6th day, with liver and renal failure, anuria and irreversible collapse. The blood and stool cultures were negative, but the histological appearance of the lesions, without any apparent suppuration, were in favour of a vascular etiology. Necrosis of the mucosa and inflammatory oedema of the sub-mucosa, were accompanied by vascular changes suggesting thrombosis and congestion.