Effect of zeolite content in the electrical, mechanical and thermal degradation response of poly(vinylidene fluoride)/NaY zeolite composites.

Polymer based composites of a-PVDF doped with different NaY zeolite (Na53Al53Si139O384) content were investigated. A good dispersion of NaY zeolite within the polymer matrix is achieved. The introduction of NaY nanoparticles enhance the storage modulus and the dielectric constant at room temperature. The dielectric constant at room temperature increases up to the value of 500 for the 32 wt% composite, at 1 kHz. The increase of the dielectric constant is mainly attributed to interfacial polarization effects. For increasing zeolite content, the nanocomposite conductivity shows two conducting regimes separted by the so called breaking voltage, which is associated to an intrazeolite charge transport. Thermogravimetric results show that the introduction of zeolites affects the thermal degradation of the polymer for low zeolite contents and also indicate the presence of water that also plays an important role in the electrical response of the materials.

Zeolite addition to improve biohydrogen production from dark fermentation of C5/C6-sugars and Sargassum sp. biomass.

Thermophilic biohydrogen production by dark fermentation from a mixture (1:1) of C5 (arabinose) and C6 (glucose) sugars, present in lignocellulosic hydrolysates, and from Sargassum sp. biomass, is studied in this work in batch assays and also in a continuous reactor experiment. Pursuing the interest of studying interactions between inorganic materials (adsorbents, conductive and others) and anaerobic bacteria, the biological processes were amended with variable amounts of a zeolite type-13X in the range of zeolite/inoculum (in VS) ratios (Z/I) of 0.065-0.26 g g-1. In the batch assays, the presence of the zeolite was beneficial to increase the hydrogen titer by 15-21% with C5 and C6-sugars as compared to the control, and an increase of 27% was observed in the batch fermentation of Sargassum sp. Hydrogen yields also increased by 10-26% with sugars in the presence of the zeolite. The rate of hydrogen production increased linearly with the Z/I ratios in the experiments with C5 and C6-sugars. In the batch assay with Sargassum sp., there was an optimum value of Z/I of 0.13 g g-1 where the H2 production rate observed was the highest, although all values were in a narrow range between 3.21 and 4.19 mmol L-1 day-1. The positive effect of the zeolite was also observed in a continuous high-rate reactor fed with C5 and C6-sugars. The increase of the organic loading rate (OLR) from 8.8 to 17.6 kg m-3 day-1 of COD led to lower hydrogen production rates but, upon zeolite addition (0.26 g g-1 VS inoculum), the hydrogen production increased significantly from 143 to 413 mL L-1 day-1. Interestingly, the presence of zeolite in the continuous operation had a remarkable impact in the microbial community and in the profile of fermentation products. The effect of zeolite could be related to several properties, including the porous structure and the associated surface area available for bacterial adhesion, potential release of trace elements, ion-exchanger capacity or ability to adsorb different compounds (i.e. protons). The observations opens novel perspectives and will stimulate further research not only in biohydrogen production, but broadly in the field of interactions between bacteria and inorganic materials.

Quantification of bleeding during dental extraction in patients on dual antiplatelet therapy.

In spite of the possibility of triggering thromboembolic events, many professionals indicate the suspension of antiplatelet agents before dental surgical procedures. The aim of this study was to perform a quantitative assessment of intraoperative bleeding in patients on dual antiplatelet therapy. A case-control study was conducted in patients on dual antiplatelet therapy (APT group) and in patients who did not use these medications (control group). The following examinations were requested: complete blood cell count, blood coagulation tests, and platelet aggregation. The quantity of bleeding was measured intraoperatively by collection of aspirated blood. The mean volume of blood lost during the surgical procedure was 6.10ml in the control group and 16.07ml in the APT group (P=0.002). The mean volume of blood lost per minute was 0.60ml/min in the control group and 1ml/min in the APT group (P=0.001), with local haemostatic methods being sufficient to control the bleeding. There was no postoperative bleeding complication in any case. Patients on dual antiplatelet therapy presented a larger volume of bleeding, but this could be controlled by means of local haemostatic measures. Therefore, there is no need to stop either of the two dual antiplatelet therapy medications before dental extractions.

The value of rapid on-site evaluation during EBUS-TBNA.

BACKGROUND: Rapid on-site evaluation (ROSE) has the potential to increase endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) accuracy in the diagnosis of mediastinal lesions and lung cancer staging. However, studies have reported controversial results. The purpose of our study was to evaluate the influence of ROSE on sample adequacy and diagnostic accuracy of EBUS-TBNA. METHODS: Prospective observational study that enrolled 81 patients who underwent EBUS-TBNA for investigation of hilo-mediastinal lesions or lung cancer staging. The first 41 patients underwent EBUS-TBNA with ROSE (ROSE group) and the last 40 patients without ROSE (non-ROSE group). Sample adequacy and diagnostic accuracy of EBUS-TBNA in both groups were compared. RESULTS: Adequate samples were obtained in 93% of the patients in the ROSE group and 80% in non-ROSE group (p=0.10). The diagnostic accuracy of EBUS-TBNA was 91% in ROSE group and 83% in non-ROSE group (p=0.08). Analyzing the EBUS-TBNA purpose, in the subgroup of patients who underwent EBUS-TBNA for investigation of hilo-mediastinal lesions, these differences between ROSE and non-ROSE group were higher compared to lung cancer staging, 93% of patients with adequate samples in the ROSE group vs. 75% in the non-ROSE group (p=0.06) and 87% of diagnostic accuracy in ROSE group vs. 77% in non-ROSE group (p=0.10). CONCLUSIONS: Despite the lack of statistical significance, ROSE appears to be particularly useful in the diagnostic work-up of hilo-mediastinal lesions, increasing the diagnostic yield of EBUS-TBNA.

[Epidemiology of certain endemic parasitic diseases in the town of Guadalupe (Republic of Sao Tome and Principe). II. Other endemic parasitic diseases]. / Epidémiologie de certaines endémies parasitaires dans la ville de Guadalupe (République de Saõ Tomé et Príncipe). II. Autres endémies parasitaires.

Stool, blood and urine specimens have been collected from 380 inhabitants of all age groups living in the small town of Guadalupe in May 1992. The seroprevalence of Falciparum malaria (96%), toxoplasmosis (73.3%), have been measured.

[Epidemiology of certain endemic parasitic diseases in the town of Guadalupe (Republic of Sao Tome and Principe) I. Schistosomiasis intercalatum and intestinal worms]. / Epidémiologie de certaines endémies parasitaires dans la ville de Guadalupe (République de Saõ Tomé et Príncipe). I. Schistosomose à S. intercalatum et verminoses intestinales.

Schistosomiasis intercalatum in known to exist in Saõ Tomé since 1988, (Corachan et al.). It is transmitted by Bulinus forskalii, (Brown et al., 1989). Stool, blood and urine specimens have been collected from 380 inhabitants of all age groups living in the small town of Guadalupe close to the Agua Traz river and Agua Polino. The prevalence of schistosomiasis by detection of S. intercalatum eggs in a 10 mg stool thick smear (Kato technique) is 25.5%. An excreted Schistosoma polysaccharide antigen, detected by means of a monoclonal antibody (Ripert et al., 1992), is found in 49.1% of the urine samples. Patients voiding S. intercalatum eggs in stools have been treated with praziquantel (40 mg/kg body weight), as recommended by WHO Expert Committee on Schistosomiasis, but it might be wise to also treat persons excreting antigen in urine. The prevalence of intestinal helminthiasis, ascariasis (73.7%), trichuriasis (73.7%) and necatoriasis have been measured.

Zooplankton community structure of two marginal lakes of the River Cuiabá (Mato Grosso, Brazil) with analysis of Rotifera and Cladocera diversity.

In the present study, two small lakes on the margins of the River Cuiabá were analyzed regarding taxonomic composition and population densities of the zooplankton. Diversity was evaluated for two groups, Rotifera and Cladocera; sampling was carried out on two dates: 2 March 1999, in the rainy season, and 25 August 1999, in the dry season. Seventy-nine rotifer taxa, 30 cladoceran taxa, and 6 copepod taxa were found. Comparing the species identified in the present study with those recorded by other authors for several water bodies in Mato Grosso and Mato Grosso do Sul states, it was found that 9 species of Cladocera, 2 of Copepoda, and 14 of Rotifera are new records for the region. The most abundant rotifer species were Keratella cochlearis, Brachionus angularis, Polyarthra vulgaris, and Keratella americana. Moina minuta and Bosminopsis deitersi were dominant among the cladocerans, and Notodiaptomus transitans and N. devoyorum among the copepods. Comparing both lakes, the greatest species richness of both Rotifera and Cladocera was observed in Lake Souza Lima, during the rainy season. This is probably linked to the fact that the littoral region of this lake is densely colonized by macrophytes. The lake also has better environmental conditions since it does not receive domestic sewage inputs, as does Lake Parque Atalaia. The diversity of the Rotifera was markedly low in Lake Parque Atalaia, during the dry season, again perhaps linked domestic sewage input found in this water body.

Lung cancer during pregnancy: an unusual case.

The incidence of pregnancy-associated cancer is relatively low, complicating only 0.02-0.1% of all pregnancies. The authors describe a case of a 36-year-old woman, a light smoker, who was admitted to the hospital at 27 weeks of pregnancy, with respiratory symptoms since second trimester. Chest-X ray showed total left lung opacity with contralateral mediastinal deviation, suggestive of pleural effusion, and the pleural biopsy revealed invasion by lung adenocarcinoma. EGFR mutation test was negative. After a multidisciplinary meeting, it was decided to start fetal lung maturation and cesarean section at 29 weeks gestation. The patient received two lines of chemotherapy and bone metastasis radiotherapy, but there was progression of the disease. An EML4-ALK translocation was identified in an additional genetic test. Crizotinib 250mg BID was started. The patient showed a progression-free survival of 9 months and died 19 months after lung adenocarcinoma was diagnosed.

Liver transplantation in a patient with clinical manifestations of cryptogenic cirrhosis: a case report of hepar lobatum as a primary liver condition.

BACKGROUND: This article reports a case of hepar lobatum, a peculiar and rare type of liver deformity, originally described in association with infectious or parasitic diseases and with malignancies. CASE REPORT: We have described a 42-year-old woman with this disorder, which was unrelated to the known conditions and referred for liver transplantation for having clinical manifestations of cirrhosis, portal hypertension, and impaired hepatic function. CONCLUSIONS: The observed histologic pattern suggests that hepar lobatum could be, in some patients, the effect of a primary process of hamartomatous origin involving the organ vascular supply.

Efficacy evaluation of educational sessions for patients with asthma and COPD.

INTRODUCTION: Asthma and COPD are respiratory diseases in which a better knowledge and understanding of the pathology allows the patients to be more involved, which is crucial in their treatment. Holding educational sessions is a good way of imparting information to the patients. AIM: To determine the efficacy of educational sessions in helping patients with Asthma and COPD to acquire a better understanding of their condition. METHODS: Following a Portuguese Lung Foundation initiative to improve knowledge about respiratory health, educational sessions for patients suffering from Asthma or COPD were organized. 25 randomized patients with the disease were invited to participate. Each session lasted 60 minutes. Patient knowledge was tested by means of a multiple choice questionnaire before and after the session. RESULTS: Fifteen patients with asthma attended the sessions, they had an average age of 36 years, of which 60% were female. Within the group 60% were able to name their pathology correctly. Seventeen patients with COPD attended the sessions, they had an average age of 69 years, of which 70% were males and only 3 (17,6%) patients were able to correctly name their pathology. In both groups, there was a statistically positive improvement (p<0,05) of correct answers to the questionnaire the end of each educational session. CONCLUSION: Patient knowledge increased in each educational session. Patients with COPD were less well informed about their disease than patients with asthma and they also had more difficulty in correctly naming their disease.

Reutilization of Cr-Y zeolite obtained by biosorption in the catalytic oxidation of volatile organic compounds.

This work aims at the reutilization of a Cr-loaded NaY zeolite obtained by biorecovery of chromium from water as catalyst in the oxidation of volatile organic compounds (VOC). Cr-NaY catalysts were obtained after biosorption of Cr(VI) using a bacterium, Arthrobacter viscosus, supported on the zeolite. The biosorption experiments were conducted at different pH values in the range 1-4. The catalysts were characterized by several techniques, namely ICP-AES, SEM-EDS, XRD, XPS, Raman, H(2)-TPR and N(2) adsorption. The zeolite obtained at pH 4 has the highest content of chromium, 0.9%, and was selected as the best catalyst for the oxidation of different VOC, namely ethyl acetate, ethanol and toluene. For all VOC tested, the catalyst with chromium showed higher activity and selectivity to CO(2), in comparison with the starting zeolite NaY. The presence of chromium shifted also the reaction pathways. In terms of selectivity to CO(2), the following sequence was observed: ethyl acetate>toluene>ethanol.

Chemical composition, oviposition deterrent and larvicidal activities against Aedes aegypti of essential oils from Piper marginatum Jacq. (Piperaceae).

The essential oils of leaves, stems and inflorescences of Piper marginatum, harvested in the Atlantic forest in the State of Pernambuco, Brazil, were obtained by hydrodistillation. GC and GC-MS analyses revealed the presence of 40 components accounting, respectively, for 99.6%, 99.7% and 99.1% of the leaf, stem and inflorescence oil, the most abundant being (Z)- or (E)-asarone and patchouli alcohol. The essential oil of the inflorescences exhibited potent activity against the 4th instar of Aedes aegypti with LC(10) and LC(50) values of 13.8 and 20.0 ppm, respectively. Furthermore, the inflorescence oil did not interfere in the oviposition of A. aegypti females when assayed at 50 ppm. These properties suggest that P. marginatum oil is a potential source of valuable larvicidal compounds for direct use or in conjunction with baits in traps constructed to capture eggs and larvae.

Quantification of bleeding during dental extraction in patients on dual antiplatelet therapy

In spite of the possibility of triggering thromboembolic events, many professionals indicate the suspension of antiplatelet agents before dental surgical procedures. The aim of this study was to perform a quantitative assessment of intraoperative bleeding in patients on dual antiplatelet therapy. A case-control study was conducted in patients on dual antiplatelet therapy (APT group) and in patients who did not use these medications (control group). The following examinations were requested: complete blood cell count, blood coagulation tests, and platelet aggregation. The quantity of bleeding was measured intraoperatively by collection of aspirated blood. The mean volume of blood lost during the surgical procedure was 6.10ml in the control group and 16.07ml in the APT group (P=0.002). The mean volume of blood lost per minute was 0.60ml/min in the control group and 1ml/min in the APT group (P=0.001)...

Immunological evaluation of human immunodeficiency virus infected individuals by flow cytometry.

Human immunodeficiency virus (HIV) infection heavily compromises the immune system. The decrease of the T cell CD4+ subset along the evolution to acquired immunodeficiency syndrome has been considered as a hallmark of HIV infection. In this paper we review some aspects of the immunopathology of HIV infection and discuss the importance of the flow cytometry for the evaluation of the T lymphocyte subsets in the follow-up of HIV infected children and adults, and for the monitoring of the immune reconstitution upon antiretroviral therapy.

Plasmodium falciparum chloroquine and quinine sensitivity in asymptomatic and symptomatic children in São Tomé Island.

Plasmodium falciparum sensitivity to quinine in São Tomé was determined by in vivo and in vitro tests in 56 children with mild or cerebral malaria. Chloroquine sensitivity was assessed by in vitro tests in 105 parasitaemic asymptomatic children from the same community as the cases. The WHO standard methodology was used. No resistance to quinine was found by in vivo or in vitro tests in either group of patients or in asymptomatic children, although some degree of chloroquine resistance was found with the in vitro test. This was more common in patients than in asymptomatic children. Chloroquine resistance may be explained by the recent history of malaria in São Tomé Island, which caused an important decrease of immunity among the population and consequently the emergence of resistant strains. Implications of the use of in vivo/in vitro tests for determining the antimalarial drug policy within the primary health care system are discussed.