Use of thin films obtained by plasma polymerization for grain protection and germination enhancement

In this work, preliminary results of the use of hydrophobic thin films obtained by plasma deposition to protect grains and seeds are presented: grains coated by the films did not present biological degradation when stored in a saturated water vapor environment, but had their germination accelerated in the presence of water. A model that explains the difference of behavior of the films when exposed to water in vapor form or in liquid form, based on the formation of microchannels within the film that lead to water uptake in seeds, is presented. The model was successfully tested using quartz crystal measurements, which showed that the microchannels within the films can favor the adsorption and permeation of water when the films are immersed in water.

Hidrogeles microestructurados de acrilamida y determinación de su capacidad de absorber agua y etanol

This paper reports the synthesis of nanostructured hydrogels of acrylamide by a two-step polymerisation process. The first step is performed by inverse microemulsion polymerization (water-in-oil) of N-isopropylacrylamide (NIPA), with these particles then added to aqueous solutions of acrylamide (AM), adding a crosslinking agent. The polymerization reaction is then initiated, thereby producing nanostructured hydrogels. We determined the capacity to absorb water, water and / or ethanol when nanostructured hydrogels were immersed in aqueous solutions with different concentrations of ethanol. It was found that the hydrogels were selective in absorbing water in all cases increasing with the ethanol concentration of the solutions.

Catálise básica usando sílica mesoporosa estabilizada por acrilatos encapsulados

The synthesis of new type of silicas, with structures akin to that of MCM-41, containing polyacrylate-encapsulated micelles in their mesopores is reported. Initially, the monomers were inserted in the aqueous micelles of cetyltrimethylammonium cations. MCM-41 was then prepared in this microemulsion. Finally, the polymerization of the acrylates was initiated by UVC radiation. The presence of monomers and polymers in the interior of micelles in aqueous media were characterized by IR spectroscopy and small-angle Xray scattering. The presence of this polymer increased the stability of these new materials in catalytic transesterification.

A NOVEL POLYACRYLAMIDE-BASED HYDROGEL CROSSLINKED WITH CELLULOSE ACETATE AND PREPARED BY PRECIPITATION POLYMERIZATION

The synthesis of polyacrylamide-cellulose acetate hydrogels by precipitation polymerization in acetone solution is reported herein. These hydrogels exhibit smaller swelling ratios and larger compression moduli than homo polyacrylamide hydrogels. For cellulose acetate concentrations above 20 wt.%, hydrogels with N,N'-methylenebisacrylamide as a crosslinker exhibit swelling ratios and compression moduli similar to those of the hydrogels without the crosslinker. A possible explanation for this behavior is that cellulose acetate crosslinks polyacrylamide via free-radical reaction. The hydrogels obtained without the N,N'-methylenebisacrylamide crosslinker exhibit compression moduli up to 1.7 MPa, making them suitable for tissue engineering applications such as cartilage replacement.

Obtention of injectable platelets rich-fibrin (i-PRF) and its polymerization with bone graft: technical note

The use of autologous platelet concentrates, represent a promising and innovator tools in the medicine and dentistry today. The goal is to accelerate hard and soft tissue healing. Among them, the platelet-rich plasma (PRP) is the main alternative for use in liquid form (injectable). These injectable form ofplatelet concentrates are often used in regenerative procedures and demonstrate good results. The aim of this study is to present an alternative to these platelet concentrates using the platelet-rich fibrin in liquid form (injectable) and its use with particulated bone graft materials in the polymerized form.

Proliferative signaling initiated in ACTH receptors

This article reviews recent results of studies aiming to elucidate modes of integrating signals initiated in ACTH receptors and FGF2 receptors, within the network system of signal transduction found in Y1 adrenocortical cells. These modes of signal integration should be central to the mechanisms underlying the regulation of the G0->G1->S transition in the adrenal cell cycle. FGF2 elicits a strong mitogenic response in G0/G1-arrested Y1 adrenocortical cells, that includes a) rapid and transient activation of extracellular signal-regulated kinases-mitogen-activated protein kinases (ERK-MAPK) (2 to 10 min), b) transcription activation of c-fos, c-jun and c-myc genes (10 to 30 min), c) induction of c-Fos and c-Myc proteins by 1 h and cyclin D1 protein by 5 h, and d) onset of DNA synthesis stimulation within 8 h. ACTH, itself a weak mitogen, interacts with FGF2 in a complex manner, blocking the FGF2 mitogenic response during the early and middle G1 phase, keeping ERK-MAPK activation and c-Fos and cyclin D1 induction at maximal levels, but post-transcriptionally inhibiting c-Myc expression. c-Fos and c-Jun proteins are mediators in both the strong and the weak mitogenic responses respectively triggered by FGF2 and ACTH. Induction of c-Fos and stimulation of DNA synthesis by ACTH are independent of PKA and are inhibited by the PKC inhibitor GF109203X. In addition, ACTH is a poor activator of ERK-MAPK, but c-Fos induction and DNA synthesis stimulation by ACTH are strongly inhibited by the inhibitor of MEK1 PD98059.

Isolation of bovine plasma albumin by liquid chromatography and its polymerization for use in immunohematology

The aim of the method described here is to remove hemoglobin, the major contaminant in the bovine plasma obtained from slaughterhouses, by adding a mixture of 19% cold ethanol and 0.6% chloroform, followed by fibrinogen and globulin precipitation by the Cohn method and nonspecific hemagglutinin by thermocoagulation. The experimental volume of bovine plasma was 2,000 ml per batch. Final purification was performed by liquid chromatography using the ion-exchange gel DEAE-Sepharose FF. The bovine albumin thus obtained presented > or = 99% purity, a yield of 25.0 ± 1.2 g/l plasma and >71.5% recovery. N-acetyl-DL-tryptophan (0.04 mmol/g protein) and sodium caprylate (0.04 mmol/g protein) were used as stabilizers and the final concentration of albumin was adjusted to 22.0% (w/v), pH 7.2 to 7.3. Viral inactivation was performed by pasteurization for 10 h at 60°C. The bovine albumin for the hemagglutination tests used in immunohematology was submitted to chemical treatment with 0.06% (w/v) glutaraldehyde and 0.1% (w/v) formaldehyde at 37°C for 12 h to obtain polymerization. A change in molecular distribution was observed after this treatment, with average contents of 56.0% monomers, 23.6% dimers, 12.2% trimers and 8.2% polymers. The tests performed demonstrated that this polymerized albumin enhances the agglutination of Rho(D)-positive red cells by anti-Rho(D) serum, permitting and improving visualization of the results.

Early life, current socioeconomic position and serum lipids in young adulthood of participants in a cohort study initiated in 1978/1979

The association between socioeconomic position (SEP) and serum lipids has been little studied and the results have been controversial. A total of 2063 young adults born in 1978/79 were evaluated at 23-25 years of age in the fourth follow-up of a cohort study carried out in Ribeirão Preto, SP, Brazil, corresponding to 31.8% of the original sample. Total serum cholesterol (TC), triglycerides, high-density cholesterol (HDL cholesterol) and low-density cholesterol (LDL cholesterol) were analyzed according to SEP at birth and during young adulthood. SEP was classified into tertiles of family income and a cumulative score of socioeconomic disadvantage was created. TC was 11.85 mg/100 mL lower among men of lower SEP in childhood (P < 0.01) but no difference was found in women, whereas it was 8.46 lower among men (P < 0.01) and 8.21 lower among women of lower SEP in adulthood (P < 0.05). Individuals of lower SEP had lower LDL and HDL cholesterol, with small differences between sexes and between the two times in life. There was no association between SEP and triglyceride levels. After adjustment of income at one time point in relation to the other, some associations lost significance. The greater the socioeconomic disadvantage accumulated along life, the lower the levels of TC, LDL and HDL cholesterol (P < 0.05). The socioeconomic gradient of TC and LDL cholesterol was inverse, representing a lower cardiovascular risk for individuals of lower SEP, while the socioeconomic gradient of HDL cholesterol indicated a lower cardiovascular risk for individuals of higher SEP.

ERICA: sexual initiation and contraception in Brazilian adolescents

ABSTRACT OBJECTIVE To estimate the prevalence of sexual initiation and contraceptive use at the last sexual intercourse of Brazilian adolescents, according to sociodemographic features. METHODS The data were obtained from the Study of Cardiovascular Risks in Adolescents (ERICA), a national school-based cross-sectional study. We included 74,589 adolescents from 32 geographic strata (27 capitals and five sets of municipalities with more than 100,000 inhabitants of each of the five macro-regions of the Country). Information on sexual initiation and contraceptive use at the last sexual intercourse (male condom and oral contraceptive pill) has been used. We have estimated prevalence and confidence intervals (95%CI) considering sample weights according to sex, age, type of school, residence status, macro-region and capitals. RESULTS We observed that 28.1% (95%CI 27.0-29.2) of the adolescents had already initiated sexual life, with higher prevalence among those aged 17 years (56.4%, 95%CI 53.9-58.9), males (33.5%, 95%CI 31.8-35.2), studying at public schools (29.9%, 95%CI 28.5-31.4), and from the Northern region (33.9%, 95%CI 32.3-35.4), mainly from Macapa, Manaus, and Rio Branco. Among those who had started their sexual life, 82.3% (95%CI 81.1-83.4) reported the use of contraceptive methods at the last intercourse, and the prevalence of use was higher among adolescents aged 17 years (85.3%, 95%CI 82.7-87.6), females (85.2%, 95%CI 83.8-86.5) and those living in the Southern region (85.9%, 95%CI 82.9-88.5). Male condom was used by 68.8% (95%CI 66.9-70.7), with no difference by type of school or macro-regions; the contraceptive pill was used by 13.4% (CI95% 12.2-14.6), and more frequently used among women (24.7%, 95%CI 22.5-27,0) and 17-year-old adolescents (20.8%, 95%CI 18.2-23.6) from urban settings(13.7%, 95%CI 12.5-14.9) and from the Southern region (22.6%, 95%CI 19.0-26.8), and less often in the Northern region. CONCLUSIONS ERICA’s data analysis on sexuality and contraception shows heterogeneities in the prevalence of sexual initiation and use of contraceptive methods among Brazilian adolescents, depending on their age, where they live, and the type of school they study at. Younger adolescents and those living in the Northern region seem to be more vulnerable to the consequences of unprotected sexual intercourses.

Activity of praziquantel against Hymenolepis nana, at different development stages, in experimentally infected mice

Single doses of praziquantel were administered by oral route, at various time intervals, following the experimental infection of mice with Hymenolepis nana eggs (2000 per animal), to investigate the drug action against different development stages of the parasite. It was shown that either 25 or 50 mg/kg given on the 4th day after inoculation had just a partial effect against the cysticercoids. Moreover, 25 mg/kg given on the 7th day was not able to kill all juvenile forms as well. However, this dose administered on the 10th day, when the parasites had reached maturity taut oviposition was not yet initiated was 100% efficacious. The same degree of efficacy was achieved with the administration of 25 mg/kg on the 14th day when the fully mature worms already lay eggs. These animal findings indicate that in the treatment of human hymenolepiasis praziquantel, 25 mg/kg, should be taken twice, 10 days apart, so that the second dose kills the larval and juvenile forms which have survived the first one. This should be particularly recommended for treating H. nana infection in close communities.

Hemorrhagic syndrome and Acute renal failure in a pregnant woman after contact with Lonomia caterpillars: a case report

A case of a 37-week pregnant woman who developed a hemorrhagic syndrome and acute renal failure after contact with Lonomia caterpillars is reported. The accident also initiated labour and the patient gave birth to an alive child. Some pathophysiological aspects of the genital bleeding and of the acute renal failure are discussed.

A 3-YEAR FOLLOW-UP OF A BRAZILIAN AIDS PATIENT WITH PROTRACTED DIARRHEA CAUSED BY Enterocytozoon bieneusi

Enterocytozoon bieneusi is the most prevalent microsporidian parasite that causes gastrointestinal infection in persons with AIDS. Microsporidia are increasingly recognized as important opportunistic pathogens all over the world but in Brazil only few cases have been reported due either to the non awareness of the clinical presentation of the disease or to difficulties in the laboratory diagnosis. We report a 3-year follow-up of a Brazilian HIV-positive patient in whom microsporidial spores were detected in stools and were identified as E. bieneusi using electron microscopy and PCR. The patient presented with chronic diarrhea, CD4 T-lymphocytes count below 100/mm3 and microsporidial spores were consistently detected in stools. Albendazole was given to the patient in several occasions with transient relief of the diarrhea, which reappeared as soon as the drug was discontinued. Nevertheless, a diarrhea-free period with weight gain up to 18 Kg occurred when a combination of nucleoside and protease inhibitors was initiated as part of the antiviral treatment.

Scedosporium apiospermum SINUSITIS AFTER BONE MARROW TRANSPLANTATION: REPORT OF A CASE

A forty-year-old man underwent an allogeneic BMT from his HLA identical sister. GvHD prophylaxis was done with cyclosporine (CyA), methotrexate and prednisone (PDN). On day +90 extensive GvHD was noted and higher doses of immunosuppressive drugs alternating CyA with PDN were initiated. Patient's follow-up was complicated by intermittent episodes of leukopenia and monthly episodes of sinusitis or pneumonia. One year after BMT, the patient developed hoarseness and nasal voice. No etiologic agent could be identified on a biopsy sample of the vocal chord. Upon tapering the doses of immunosuppressive drugs, the patient had worsening of chronic GvHD and was reintroduced on high doses of cyclosporine alternating with prednisone on day +550. Three months later, GvHD remained out of control and the patient was started on azathioprine. On day +700, hoarseness and nasal voice recurred. Another biopsy of the left vocal chord failed to demonstrate infection. Episodes of sinusitis became more frequent and azathioprine was withheld 3 months after it was started. One month later, the patient had bloody nasal discharge and surgical drainage of maxillary sinuses was performed. Histopathology showed hyphae and cultures grew Scedosporium apiospermum. ltraconazole 800 mg/day was initiated. The patient developed progressive respiratory failure and died 15 days later.

Central nervous system paracoccidioidomycosis. Report of a case successfully treated with Itraconazol

Paracoccidioidomycosis (PCM) is a primary pulmonary infection that often disseminates to other organs and systems. Involvement of the central nervous system (CNS) is rare and due to the fact that both clinical alertness and establishment of the diagnosis are delayed, the disease progresses causing serious problems. We report here a case of neuroparacoccidioidomycosis (NPCM), observed in a 55 year-old male, who consulted due to neurological symptoms (left hemiparesis, paresthesias, right palpebral ptosis, headache, vomiting and tonic clonic seizures) of a month duration. Upon physical examination, an ulcerated granulomatous lesion was observed in the abdomen. To confirm the diagnosis a stereotactic biopsy was taken; additionally, mycological tests from the ulcerated lesion and a bronchoalveolar lavage were performed. In the latter specimens, P. brasiliensis yeast cells were visualized and later on, the brain biopsy revealed the presence of the fungus. Treatment with itraconazole (ITZ) was initiated but clinical improvement was unremarkable; due to the fact that the patient was taking sodium valproate for seizure control, drug interactions were suspected and confirmed by absence of ITZ plasma levels. The latter medication was changed to clonazepam and after several weeks, clinical improvement began to be noticed and was accompanied by diminishing P. brasiliensis antigen and antibody titers. In the PCM endemic areas, CNS involvement should be considered more often and the efficacy of itraconazole therapy should also be taken into consideration.

Seroprevalence of hepatitis B and C infection markers among children and adolescents in the southern Brazilian region

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections account for a substantial proportion of liver diseases worldwide. The aim of this study was to determine the prevalence of HBV and HCV serological markers among children and adolescents and verify the epidemiology of the HBV infection over than a decade of the introduction of vaccination program. Serologic markers to HBsAg, total anti-HBc and anti-HCV had been tested in 393 samples. The seropositivity for HBsAg was 0.76% and for total anti-HBc was 1.02%. Copositivity between HBsAg and total anti-HBc was verified in 0.76% of the analyzed samples. There was no seropositivity for anti-HCV marker. The seroprevalence of HBV infection markers among children and adolescents in the southern Brazilian region is high compared to that reported in other countries. Preventive measures, such as educational activities in addition to the universal childhood HBV vaccination, should be initiated in order to reduce the morbimortality and the economic burden associated with the disease.