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Electrical resistivity experiments show superconductivity atTc=1.1K in a high-quality single crystal of trigonalγ-PtBi2, with an enhanced critical magnetic fieldµ0Hc2(0)≳1.5Tesla and a low critical current-densityJc(0)≈40 A cm-2atH = 0. BothTcandHc2(0)are the highest reported values for stoichiometric bulk samples at ambient pressure. We found a weakHc2anisotropy withΓ=Hc2ab/Hc2c<1, which is unusual among superconductors. Under a magnetic field, the superconducting transition becomes broader and asymmetric. Along with the low critical currents, this observation suggests an inhomogeneous superconducting state. In fact, no trace of superconductivity is observed through field-cooling-zero-field-cooling magnetization experiments.

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WSP technology has been used in Ceará, Northeast Brazil, since middle 1970s. There are presently 96 ponds plants and most of them are comprised by single cells (40%) and series of 3 ponds (35%). They were under loaded due to incomplete house connections to the sewerage network and low per capita wastewater contributions. Highest removal rates of organic material, ammonia and faecal coliform were found in 3 pond series. Faecal coliform removal was in accordance with the literature and series of ponds reached numbers ≤10(5) cells/100 ml. In series with 4 and 5 ponds FC was below 10(3) cells/100 ml. Ammonia removal varied from 30 to 80% and total phosphorus the removal was not significant. An increase in the number of maturation ponds enhances nutrient and coliform removal. Up-grading schemes should be investigated as well as effluent reuse potential.

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Hydrogen storage materials can form more than one hydride phase. These different phases, in turn, display different hydrogen absorption/desorption capacities, kinetics, and stabilities. Studies aimed at characterizing and improving these materials usually need to correlate hydrogen intake with the precise determination of the hydride phase involved in the process. Here, we present a device designed to perform measurements of well known volumetric techniques with simultaneous x-ray diffraction on the material under study. The compact design can stand up to 6000 kPa of internal pressure while the sample can be heated up to 450 degrees C. The design process was assisted by finite element modeling and by the use of mock-up prototypes in order to optimize the thermal and under load behaviors. We provide two examples of use for this new device: (1) hydride decomposition in LaNi5 at 115 degrees C and (2) formation of MgCo during the programmed thermal desorption of the Mg2CoH5 hydride.

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Hydrogen storage materials suffer different degradation processes when they are cycled, forming and decomposing their associated hydride phases. In order to study these processes, we have designed and built an automated apparatus specifically developed for cycling samples of hydride forming materials by changing the external hydrogen pressure. Instead of the standard open configuration involving a high-pressure, high-quality gas bottle and a vacuum pump, the equipment uses another hydride forming material (in our case LaNi5) as a source and sink of hydrogen. The resulting closed-loop configuration eliminates hydrogen waste and ensures that extremely high purity gas is used during the whole experiment, thanks to the purifying properties of the selected hydride as source/sink. Hydrogen pressure is set by changing the source/sink temperature. Cycles can be performed as fast as one cycle every 5 min, a period comparable with typical good hydride forming material kinetics. An example of application of the apparatus is given for 1000 absorption/ desorption cycles on a Mm0.8Ca0.2Ni5 sample.

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Treatment of chronic hepatitis C consists of inteferon plus ribavirin. The major adverse effect of ribavirin is hemolytic anemia, a complication that limits therapy. Folic acid supplementation is used to improve erythropoiesis in chronic hemolytic anemia. The aim of this study was to evaluate the effectiveness of folic acid supplementation in the prevention of ribavirin-induced anemia in patients being treated for hepatitis C. Twenty one patients enrolled in treatment protocols for hepatitis C received folic acid 1 mg daily and 22 did not. Groups were similar in age, gender, ribavirin dose and baseline hemoglobin. Folic acid supplementation had no effect in the decrease in hemoglobin or the measured parameters of hemolysis. No difference between males and females was noted for hemoglobin decrease or lowest hemoglobin levels. In our study, folic acid showed no beneficial effect in the prevention of ribavirin-induced anemia.

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Aim: Tocompare four anti-H. pylori regimes using omeprazole and azithromycin associated to different antimicrobials in peptic ulcer H. pylori positive patients. Patients and methodos: afterinformed consent, 136 endoscopically proven peptic ulcer patients(74 male, 62 female) were randomly assigned to one of thefollowing therapy groups: Group 1: Om 20mg mane for 7 ays + Az 500mgmane for 3 days + tinidazole (Ti) 500mg bid for 7 ays. Group 2: Om 20 mg mane for 7 days + Az 500mane for 3 days + amoxycilin (Am) 500mg tid for 7 days. Group 3 Om 20 mg mane for 7 days + Az 500mg mane for 3 days + furazolidone (F) 200 mg tid for 7 days. Group 4: Om 20 mg mane for 7 days +Az 500mg mane for 3 days + colloidal bismuth subcitrate (CBS) 120 mg tid ( double dose at bedtime) for7 days. The H. Pylori status was assessed before treatment and 94 (63-214) days post treatment using urease test, and 14C-urea breath test. Statistical analysis was performed by Kruskal-Wallis test, chi-square test, Fisher's exact test, and Lancaster & Irvin method. Results: The four groups had similar demographic and clinical characteristics. 120/136 patients completed the study. One patient discontinued treatment due to side effects and 15 were lost to follow-up.32/136 (23.5por cento) hed side effect during treatment, mainly nause. H.pylori eradication in group 3 was statistically different from the other groups ( p=0.000). Group 3 & 4 (statistically non-different) presented significantly more side effects than group 1 and 2 (p=0.002). Conclusion: 1)Om + Associated to F (the cheapest ant- H.Pylori drug) for one week represents an efficient reasonaaable well-tolerates alternatiaaaaaave to H.pylori eradication. 2) Future studies testing F with other macrolides or Az during 7 days can enhance H. Pylori eradication rates

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In order to test theoretical predictions, we have studied the phenomenon of stochastic resonance in an electronic experimental system driven by white non-Gaussian noise. In agreement with the theoretical predictions our main findings are an enhancement of the sensibility of the system together with a remarkable widening of the response (robustness). This implies that even a single resonant unit can reach a marked reduction in the need for noise tuning.

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Background: There is not yet consensus on the most effective treatment for the helicobacter pylori infection, particularly in most developing countries. Azithromycin is a new macrolide and relatively novel agent for H. pylori eradication with an in vitro MIC90 lower than 1 mg/ml.Secnidazole, a nitromidazole that causes fewer side effects than metronidazole, was recenty reported to be used, for the firt time, in the treatment of H. pylori infection. Aim: To evaluate, in a prospective, randomized, single-center study, the association of twodifferent doses of omeprazole, azithromycin and secnidazole in H. pylori eradication. Patients and methods: After informed consent, 55 patients (36m,19F) with duodenal ulcer associated with H. pylori infection were randomized to receive omeprazole 20mg uid (Group A) or 20mg bid (Group B) for sevem days plus azithromycin 500mg uid for six days and secnidazole 2,000mg uid in the first, fourth and seventh day. The H. pylori status was assessed before and 60-90 days posttreatment using urease test, histology and 13C-urea breath test. Statistical analysis was performed by X² test. Results: The two groups had similar demographic characteristics. Fifty-five patients (36M, 19F) were enrolled. Six patients did not show-up for the second visit posttreatment. So, of the 49 evaluable patients, 25por cento (6/24) in Group A and 44por cento(11/25) in Group B wereeradicated, in a per protocol (PP) analysis. Intetion-to-treat (ITT) eradication rates were 21,4por cento (6/28) in Group A and 40.7por cento (11/27) im Group B. The differences betweem ITT and PP analysis from the two groups were not statistically significant. Conclusions: This study shows a very low eradication rate with the two regimens comprising of omeprazole, azithromycin and secnidazole and therefore, should not be recommended for thetreatment of H. pylori infection

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BACKGROUND: During the last 3 decades, colonoscopy has become the diagnostic study with greatest sensitivity and acuity in colonic pathology. AIMS: To know the most frequent diagnostic and colonoscopic disorders, and the pathology found, to establish certainty of the colonoscopic procedure. METHOD: Between 1987 and 1997, a descriptive, transversal, retrospective and observational study of the 2,000 colonoscopies that were carried out at on service was done, making a registry of the endoscopic search in colorectal pathology and their characteristics in on patients. RESULTS: Colonoscopies were done in 967 men (47.3%) and 1,053 women (52.6%) with a median age of 55.8 years (10 range (-) 93 years). In 1,780 of them (89.%), it was possible to arrive to cecum; 1,150 (57.5%) were pathologic. The most frequent finding was hemorrhage of the lower digestive tube in 525 (26.2%) patients; in addition cancer in 402 (20.1%), suspicion of intestinal inflammatory disease 292 (14.6%) and colorectal polyps 199 (10%) were found. The most frequent endoscopic diagnosis was colorectal polyps in 405 (35.7%) patients; in additions diverticular disease was found in 404 (35.1%) patients intestinal inflammatory disease in 185 (16%), colorectal cancer in 85 (7.4%), and vascular ectasias in 52 (4.5%) patients. There were four complicated cases (0.25%), three by resolved therapeutic colonoscopy and one diagnostically. CONCLUSION: The most frequent colonoscopic were findings hemorrhage of the lower digestive tube and the finding of cancer. The most frequent diagnoses were colorectal polyps and diverticular disease. Colonoscopy is a safe diagnostic and therapeutic procedure.

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The aim of this work was to compare the performance of isotope-selective non-dispersive infrared spectrometry (IRIS) for the 13C-urea breath test with the combination of the 14C-urea breath test (14C-UBT), urease test and histologic examination for the diagnosis of H. pylori (HP) infection. Fifty-three duodenal ulcer patients were studied. All patients were submitted to gastroscopy to detect HP by the urease test, histologic examination and 14C-UBT. To be included in the study the results of the 3 tests had to be concordant. Within one month after admission to the study the patients were submitted to IRIS with breath samples collected before and 30 min after the ingestion of 75 mg 13C-urea dissolved in 200 ml of orange juice. The samples were mailed and analyzed 11.5 (4-21) days after collection. Data were analyzed statistically by the chi-square and Mann-Whitney test and by the Spearman correlation coefficient. Twenty-six patients were HP positive and 27 negative. There was 100% agreement between the IRIS results and the HP status determined by the other three methods. Using a cutoff value of delta-over-baseline (DOB) above 4.0 the IRIS showed a mean value of 19.38 (minimum = 4.2, maximum = 41.3, SD = 10.9) for HP-positive patients and a mean value of 0.88 (minimum = 0.10, maximum = 2.5, SD = 0.71) for negative patients. Using a cutoff value corresponding to 0.800% CO2/weight (kg), the 14C-UBT showed a mean value of 2.78 (minimum = 0.89, maximum = 5.22, SD = 1.18) in HP-positive patients. HP-negative patients showed a mean value of 0.37 (minimum = 0.13, maximum = 0.77, SD = 0.17). IRIS is a low-cost, easy to manage, highly sensitive and specific test for H. pylori detection. Storing and mailing the samples did not interfere with the performance of the test.

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The aim of this work was to compare the performance of isotope-selective non-dispersive infrared spectrometry (IRIS) for the 13C-urea breath test with the combination of the 14C-urea breath test (14C-UBT), urease test and histologic examination for the diagnosis of H. pylori (HP) infection. Fifty-three duodenal ulcer patients were studied. All patients were submitted to gastroscopy to detect HP by the urease test, histologic examination and 14C-UBT. To be included in the study the results of the 3 tests had to be concordant. Within one month after admission to the study the patients were submitted to IRIS with breath samples collected before and 30 min after the ingestion of 75 mg 13C-urea dissolved in 200 ml of orange juice. The samples were mailed and analyzed 11.5 (4-21) days after collection. Data were analyzed statistically by the chi-square and Mann-Whitney test and by the Spearman correlation coefficient. Twenty-six patients were HP positive and 27 negative. There was 100 per cent agreement between the IRIS results and the HP status determined by the other three methods. Using a cutoff value of delta-over-baseline (DOB) above 4.0 the IRIS showed a mean value of 19.38 (minimum = 4.2, maximum = 41.3, SD = 10.9) for HP-positive patients and a mean value of 0.88 (minimum = 0.10, maximum = 2.5, SD = 0.71) for negative patients. Using a cutoff value corresponding to 0.800 per cent CO2/weight (kg), the 14C-UBT showed a mean value of 2.78 (minimum = 0.89, maximum = 5.22, SD = 1.18) in HP-positive patients. HP-negative patients showed a mean value of 0.37 (minimum = 0.13, maximum = 0.77, SD = 0.17). IRIS is a low-cost, easy to manage, highly sensitive and specific test for H. pylori detection. Storing and mailing the samples did not interfere with the performance of the test.

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OBJECTIVE: Case report of a malignant stromal tumor of the transverse colon. BACKGROUND: Colon sarcomas are rare; the most frequent presentation is the leiomyosarcoma. Forty five cases of malignant stromal tumor have been reported in the international literature. The histogenesis of these mesenchymatous neoplasms is determined by ultrastructural analysis and immunohistochemical stains, nevertheless when special techniques are negative and there is uncertainty related to the cellular differentiation line (smooth muscle, neural or undifferentiated) it is preferable to call them stromal tumors of gastrointestinal tract. METHOD: A 46 year old patient with the diagnosis of malignant stromal tumor of transverse colon and the prescribed treatment was reported. RESULTS: A case of a patient with the diagnosis of malignant stromal tumor in transverse colon is presented, who had as the main clinical features abdominal pain, transanal hemorrhage and finally intestinal occlusion. He was submitted to exploratory laparotomy finding a transverse colon intussusception, which was treated with an extended right hemicolectomy and a post surgical satisfactory recovery. Follow-up to three years hasn't found tumoral activity. CONCLUSIONS: Stromal tumors are rare in colon, treatment is a wide surgical resection with curative or palliative purposes.

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Foram estudados 98 pacientes com úlcera péptica duodenal distribuídos de forma randômica em dois grupos. Um grupo recebeu antiácido liquido de alta potência (282,4mEq/dia) dividido em 4 tomadas durante 4 semanas e outro recebeu cimetidina (800 mg/dia) dividida em 2 tomadas por igual período. A potência antiácida da associaçäo líquida utilizada é de 7,06 mEq/ml. Todos os pacientes foram avaliados clinicamente no pré-tratamento e duas e quatro semanas após, com exames endoscópicos realizados na admissäo e após quatro semanas. A eficácia, considerada como cicatrizaçäo da úlcera duodenal associada a melhora da sintomatologia foi equivalente para ambos os tratamentos, näo havendo diferença estatisticamente significante. A tolerabilidade de ambas as drogas foi considerada boa

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Two hundred and forty-one patients with at least one ulcer at stage A1 or A2, measuring at least 5 mm in its larger diameter, were included in this Brazilian double-blind randomized study. Patients received omeprazole 20 mg in the morning (n = 120) or ranitidine 300 mg at night (n = 121) for 2 wk; unhealed ulcers were treated for an additional 2 wk. At the end of 4 wk, unhealed ulcers were treated openly with omeprazole 20 mg o.m. for 4 wk. Healing rates at 2 and 4 wk were 67.3% and 92.9% for omeprazole and 39.8% and 82.0% for ranitidine (per protocol analysis). Results were similar when analyzed as intention to treat (p significant in favor of omeprazole). Epigastric day-time pain was the most common of all symptoms (89.2%), but only heartburn at day 15 showed a significantly better response to omeprazole than to ranitidine. A multivariate analysis (logit analysis) showed that the odds in favor of healing were greater for small ulcers, nonsmokers, and omeprazole treatment.

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1. Endoscopic staging of peptic ulcer lesions according to Sakita will be a methodological improvement in therapeutic trials provided that the correlation between stages and the time spent in treatment is proved valid. 2. We describe a double-blind controlled randomized trial carried out to determine the efficacy of cimetidine in patients with duodenal ulcer in the H stage of Sakita endoscopic staging. Fifty-two patients with duodenal ulcer (H stage) were randomly allocated to receive either 400 mg cimetidine twice daily (N = 26), or placebo (N = 26) for two weeks; patients with unhealed ulcers continued the same treatment for an additional week. 3. Of the cimetidine-treated patients, 19 (73%) were healed after two weeks and 23 (88.5%) after three weeks of treatment, and of the placebo-treated patients, 8 (31%) were healed after two and 13 (50%) after three weeks. 4. These differences indicate a natural tendency of the H stage lesions to heal faster than reported for the active (stage A) lesions and still faster if treated with cimetidine. These findings, by establishing a relationship between the ulcer stage and the time spent in treatment, may help the physician to treat duodenal ulcer patients and will enable the adoption of an important, uniform criterion for selection of duodenal ulcer patients for therapeutic trials, especially in multicenter trials.

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Endoscopic staging of peptic ulcer lesions according to Sakita will be a methodological improvement in therapeutic trials provided that the correlation between stages and the time spent in treatments is proved valid. We describe a double-blind controlled randomized trial carried out to determine the efficacy of cimentidine in patients with duodenal ulcer in the H stage of Sakita endoscopic staging. Fifty-two patients with duodenal ulcer (H stage) were randomly allocated to receive either 400 mg cimetidine twice daily (N = 26), or placebo (N = 26) for two weeks; patients with unhealed ulcers continued the same treatment for an additional week. Of the cimetidine-treated patients, 19 (73%) were healed after two weeks and 23 (88.5%) after three weeks of treatment, and of the placebo-treated patients, 8 (31%) were healed after two and 13 (50%) after three weeks. These differences indicate a natural tendency of the H stage lesions to heal faster than reported for the active (stage A) lesions and still faster if treated with cimetidine. These findings, by establishing a relationship between the ulcer stage and the time spent in treatment, may help the physician to treat duodenal ulcer patients and will enable the adoption of an important, uniform criterion for selection of duodenal ulcer patients for therapeutic trials, especially in multicenter trials

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