Frozen spatial coherence.

Inspired by the concept of coherent frozen waves, this paper introduces one possible theoretical framework of its partially coherent version, a frozen spatial coherence, in which a desired two-point correlation structure of an optical field is created on the propagation axis by superposing partially coherent zero-order Bessel beams. It is shown that the cross-spectral density can be given a description in terms of a two-dimensional Fourier series, analogous to the one-dimensional approach of coherent frozen waves. The formalism is applied to the design of a partially coherent field which is highly coherent only if the pair of points in the propagation axis belong to a predetermined and finite range and highly incoherent outside that range.

Detection and quantification of hepatitis E virus in the absence of IgG and IgM anti-HEV in HIV-positive patients.

AIMS: To improve RT-qPCR with an internal control and a synthetic standard curve to detect HEV in HIV co-infected patients. METHODS AND RESULTS: A single-stranded RNA (ssRNA) and a double-stranded DNA (dsDNA) synthetic curve were designed, compared to the international reference panel for HEV genotypes, and tested to quantify and detect a reference panel for HEV genotypes. The detection limit of the RNA synthetic curve (50 copies per ml) was better than the DNA synthetic curve (100 copies per ml) and the WHO standard curve (250 copies per ml). Then, 280 serum samples from HIV-positive patients were tested for HEV RNA, which was detected in 3·6% of serum samples. The viral load ranged from 2 × 102 copies per ml to 4·78 × 108 copies per ml. HEV IgM/IgG antibodies were not detected in the RNA-positive patients. Sequencing analysis of HEV showed that the virus belongs to genotype 3 (HEV GT3). CONCLUSIONS: Real-time PCR was a useful tool to estimate co-infection with HEV/HIV, even in patients with low viral loads and undetectable anti-HEV IgG and IgM antibodies. SIGNIFICANCE AND IMPACT OF THE STUDY: Hepatitis E virus genotype 3 (HEV GT3) has been associated with silent chronic hepatitis and cirrhosis in HIV-positive subjects worldwide, but there is a lack of data on this co-infection in Brazil.

Seroprevalence of hepatitis E antibodies in a population of recyclable waste pickers in Brazil.

BACKGROUND: Hepatitis E virus (HEV) infection represents an important cause of acute viral hepatitis. Selective waste collection is a widespread activity carried out by the urban poor, and recyclable waste pickers have a lifestyle that makes this group highly vulnerable to unfavorable socio-economic and environmental factors. To date, the epidemiology of HEV infection in this population remains unknown. OBJECTIVES: To assess the seroprevalence of hepatitis E-specific antibodies in a population of recyclable waste pickers in Brazil. STUDY DESIGN: Between April 2010 and May 2011, a cross-sectional study was conducted among recyclable waste pickers from all 15 recycling cooperatives in Goiânia City, Central Brazil. The participants were tested for serological markers indicative of HEV infection. RESULTS: Of 432 individuals asked to participate in the survey, 431 (99.8%) agreed to participate. Twenty-four of 431 participants were anti-HEV IgG positive by ELISA. Of these, 22 were confirmed positive by immunoblot, resulting in an anti-HEV IgG prevalence of 5.1% (95% CI: 3.4-7.6). In addition, four individuals were anti-HEV IgM positive by ELISA. Of these, three (0.7%; 95% CI: 0.4-2.4) were confirmed anti-HEV IgM positive by immunoblot, but were HEV RNA negative. One was concurrently positive for anti-HEV IgG. Only age>40 years was independently associated with the presence of anti-HEV. CONCLUSIONS: These findings demonstrated that the prevalence of HEV antibodies among recyclable waste pickers in Central Brazil is relatively low and increased with age.

Hepatitis E virus infection in Latin America: a review.

Data reported during recent years reveal the complex picture of the epidemiology of hepatitis E virus (HEV) infection in Latin America. Whereas in countries like Argentina and Brazil is almost identical to the characteristic of most countries from North America and Europe, HEV in the Caribbean and Mexico involves the water-borne, non-zoonotic viral genotypes responsible for epidemics in Asia and Africa. Nevertheless, Latin America has been considered a highly endemic region for hepatitis E in the scientific literature, a generalization that ignores the above complexity. In addition, reports from isolated Amerindian communities, which display well known, important and very specific epidemiological features for hepatitis B and D virus infections are neither taken into account when considering the epidemiology of hepatitis E in the region. This review updates compilation of the available information for the HEV infection, both among humans and other mammals, in Latin America, discusses the strengths and the weaknesses of our current knowledge, and identifies future areas of research.

Óleo essencial de Baccharis trimera (Less. ) DC. sobre o potencial fisiológico de sementes de feijão caupi / The essential oil effects of Baccharis trimera (Less. ) DC. on the physiological potential of cowpea bean seeds

O presente trabalho teve como objetivo avaliar o efeito alelopático do óleo essencial de plantas de carqueja, Baccharis trimera (Less.) DC., sobre a germinação de sementes de feijão Vigna unguiculata (L.) Walp. Foi avaliado o efeito do óleo essencial de B. trimera sobre V. unguiculata nas dosagens 20 μL, 15 μL, 10 μL, 5 μL e testemunha. A qualidade fisiológica das sementes foi determinada pela porcentagem de emergência, velocidade de emergência e índice de velocidade de emergência. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial 5 x 2 com cinco repetições. Não foi observado efeito inibidor do óleo essencial de B. trimera na germinação de sementes de feijão caupi, caracterizando-se como de efeito alelopático benéfico. De acordo com os resultados obtidos, o óleo essencial de B. trimera revelou-se eficiente na manutenção da viabilidade dessas sementes.

This research aimed to evaluate the allellopathic effect of essential oils of the Baccharis trimera (Less.) DC. plants on the seeds germination of cowpea Vigna unguiculata (L.) Walp. The effect of B. trimera essential oil on V. unguiculata was evaluated at levels of 20 μL, 15 μL, 10 μL, 5 μL and control. The physiologic quality of the seeds was determined by percentage emergence, the rate of speed emergence and speed emergence index. The data analysis was carried out using an entirely randomized design, in a 5 x 2 factorial scheme with five repetitions. An inhibitory effect of B. trimera essential oil on bean seeds germination was not observed, which is characterized as a beneficial allelopathic effect. Based on the results, the B. trimera essential oil proved efficient in the viability maintenance of these seeds.

Viabilidade de sementes de feijão caupi após o tratamento com óleo essencial de citronela (Cymbopogon winterianus Jowitt) / Viability of Vigna unguiculata bean seeds treated with essential oil of Java grass (Cymbopogon winterianus Jowitt)

O tratamento de sementes com óleos essenciais é um método alternativo que auxilia o manejo integrado de pragas. O objetivo deste trabalho foi avaliar a influência do tratamento de sementes de feijão Vigna unguiculata (L.) Walp. com o óleo essencial de citronela (Cymbopogon winterianus Jowitt). Foi avaliado o efeito do óleo essencial de C. winterianus sobre V. unguiculata nas dosagens 20 µL, 15 µL, 10 µL, 5 µL e testemunha. A qualidade fisiológica das sementes foi determinada pela porcentagem de emergência, velocidade de emergência e índice de velocidade de emergência. A análise dos dados foi realizada no delineamento inteiramente casualizado, disposto em esquema fatorial 5 x 2 com cinco repetições. As sementes fumigadas apresentaram diferenças estatísticas entre os parâmetros avaliados em relação à testemunha. O óleo essencial de citronela revelou potencialidade alelopática sobre a germinação de sementes de feijão que variou de acordo com a concentração do óleo.

Seed treatment with essential oils is an alternative method tool in integrated pest management. The objective of this study was to evaluate the effect of treating Vigna unguiculata (L.) Walp. bean seeds with essential oil of Java grass (Cymbopogon winterianus Jowitt). The effect of C. winterianus essential oil on P. vulgaris was evaluated at levels of 20 µL, 15 µL, 10 µL, 5 µL and control. The physiologic quality of the seeds was determined by percentage emergence, speed emergence and speed emergence index. The data analysis was carried out using an entirely randomized design, in a 5 x 2 factorial scheme with five repetitions. The fumigated bean seeds showed the statistics differences among the analyzed parameters when was compared with the no treated check. The essential oil of Java grass revealed allelopathic potentiality on bean seed germination which varied according to the oil concentration.

The use of dried blood spots for assessing antibody response to hepatitis A virus after natural infection and vaccination.

During recent years, vaccination against hepatitis A has been implemented in several countries. It is expected that the increase in mass vaccination against hepatitis A will eventually result in a decreased prevalence of anti-HAV antibodies in the general population. For this reason, a suitable clinical sample for diagnosis of hepatitis A must be sufficiently sensitive to enable detection of lower antibodies titers. In this study, the feasibility of using dried blood spots (DBS) was assessed for the detection of anti-HAV antibodies after a natural infection and vaccination. Seventy-four DBS and paired plasma samples were obtained from a group of college students for a cross-sectional hepatitis A seroepidemiological study. Forty-six students seronegative for anti-HAV were selected randomly and immunized with an inactivated hepatitis A vaccine using an 0-6 month schedule. Seroconversion was monitored in paired plasma and DBS samples 6 months after the first dose followed by a period of 8 and 24 months after the second dose. A strong correlation between OD/CO rates of paired plasma and DBS samples for the detection of anti-HAV was observed. The sensitivity and specificity of the DBS compared with plasma for the detection of anti-HAV antibodies after natural infection was 100%. The sensitivity of DBS in samples collected 24 months after the second dose of hepatitis A vaccine was 95.4%. The results showed that DBS samples can be used for the detection of anti-HAV antibodies both after natural infection or vaccination.

Kinetics of hepatitis A virus replication in vivo and in vitro using negative-strand quantitative PCR.

The replication of hepatitis A virus (HAV) is via a complementary negative-strand RNA. Each negative strand may serve as a template for the synthesis of many positive strands. The aim of this study was to detect the intermediate replicative (negative strand) of HAV in order to monitor its replication in vitro and in vivo. Real-time polymerase chain reaction (PCR) was standardized to detect the intermediate replicative of HAV in cell culture and liver from non-human primates infected experimentally. HAV primers from the 5' non-translated region and VP3 were used in the cDNA synthesis of negative-strand RNA. The negative strand was detected in the infected cell lines and liver by highly strand-specific rTth recombinant Thermus thermophilus DNA polymerase reverse transcription followed by quantitative PCR. The results indicate that the negative-strand HAV RNA can be detected in vivo and in vitro. This model is an approach for assessing the dynamic patterns of replication and should represent a valuable tool for the monitoring of HAV replications in cell cultures and for the evaluation of experimental infections in animal models.

Leishmania infantum-induced primary and challenge infections in rhesus monkeys (Macaca mulatta): a primate model for visceral leishmaniasis.

Visceral leishmaniasis (VL) was experimentally induced in rhesus macaques (Macaca mulatta) by intravenously inoculating 2 x 10(7)amastigotes/kg of body weight of Leishmania infantum. The macaques developed a systemic disease showing characteristic features of human VL such as fever, diarrhoea, body weight loss, anaemia, hypergammaglobulinaemia and transient lymphocytosis, as well as lymph node, liver and/or spleen enlargement. Nine weeks after infection, one primate showed pronounced weight loss, became moribund and was euthanized. The necropsy findings included granulomas composed of parasite-containing macrophages, lymphocytes and plasma cells in the liver, spleen and lymph nodes. The remaining macaques had a sustained course of infection but developed a mild-to-moderate illness that subsequently showed evidence of self-cure. Of note, pathological findings included a typical cell-mediated immunity-induced granulomatous reaction that had an effect on the control of parasite replication. All infected monkeys responded with increased production of anti-Leishmania-specific IgG antibodies. Despite the fact that clinical resistance to L. infantum was not consistently associated with a parasite-specific cell-mediated immune response, drug-cured macaques from the primary infection acquired immunity to homologous re-infection. These findings point to the feasibility of using the L. infantum macaque model for pre-clinical evaluation of novel chemotherapeutics or vaccine candidates for human VL.

Detection of hepatitis C virus RNA by in situ hybridization in paraformaldehyde fixed biopsies.

Fourteen hepatitis C virus (HCV) chronically infected patients were submitted to routine liver biopsy for histological evaluation. Liver samples were assayed to HCV-RNA by in situ hybridization, using digoxigenin labeled probe. HCV genotypes were found to be predominantly type 1 (71.4%), followed by genotype 3 (21.4%), and genotype 2 (7.2%). Alanine-aminotransferase levels were raised in 10 patients. The histopathological scores were minimal (21.4%), mild (57.2%), and moderate (21.4%). Viral RNA was detected in liver cells from nine patients (64.3%). ISH method provides localization and poor confirmation of HCV RNA in the liver tissue of HCV chronic patients.

Detection of hepatitis C virus RNA by in situ hybridization in paraformaldehyde fixed biopsies

Fourteen hepatitis C virus (HCV) chronically infected patients were submitted to routine liver biopsy for histological evaluation. Liver samples were assayed to HCV-RNA by in situ hybridization, using digoxigenin labeled probe. HCV genotypes were found to be predominantly type 1 (71.4 percent), followed by genotype 3 (21.4 percent), and genotype 2 (7.2 percent). Alanine-aminotransferase levels were raised in 10 patients. The histopathological scores were minimal (21.4 percent), mild (57.2 percent), and moderate (21.4 percent). Viral RNA was detected in liver cells from nine patients (64.3 percent). ISH method provides localization and poor confirmation of HCV RNA in the liver tissue of HCV chronic patients.

Fibular segment bone bridging in trans-tibial amputation.

The purpose of this paper is to present an alternative method of achieving a synostosis between tibia and fibula in trans-tibial amputations by means of a fibular segment in place of tibial osteoperiosteal flaps as described by Ertl, in 1949. From May 1997 through to February 2003, 15 patients were submitted to the proposed procedure. As a result, all patients produced a solid synostosis between tibia and fibula and were rehabilitated with the use of prostheses. The capacity of these patients for distal weight-bearing on the stump was remarkable when compared to patients submitted to the conventional trans-tibial amputation technique.

Experimental hepatitis A virus (HAV) infection in Callithrix jacchus: early detection of HAV antigen and viral fate.

Common marmosets (Callithrixjacchus) were orally inoculated with a Brazilian strain (HAF-203) of hepatitis A virus (HAy). Three monkeys were euthanized at postinoculation hours 6, 12 and 24 to investigate the early events of HAV infection. Following others three inoculated and one control marmosets remained throughout the 46 day to evaluation of viral excretion. Different samples were collected to detect sequential presence of HAV RNA by nested reverse transcription-polymerase chain reaction (RT-PCR) in liver, saliva, bile and stools at 6 hours to 461h days postinoculation. Liver tissues were examined by immunofluorescence assay in a confocal laser-scanning microscope for the presence of HAV antigen. HAV RNA was detected in saliva during the course of the study, in bile from 24 hours to 46 days. in stools from 7 to 46 days and liver at 12 hours postinfection. In immunofluorescence of liver stained preparations, viral antigen was present at six hours after inoculation throughout the remainder of the 46-day study. The animals developed histological and biochemical acute hepatitis after second week postinoculation. Spleen, duodenum, and mesenteric lymph nodes specimens were negative for HAV antigens. This study supports the possibility that in Callithrixjacchus orally inoculated with hepatitis A virus the saliva route may be additional way of viral elimination. The viral replication in the liver was responsible for biliary HAV presence and latter HAV detection in fecal samples.

Thrombolytic effect of lonomin V in a rabbit jugular vein thrombosis model.

Thrombolytic efficacy of lonomin V (LV), a protein isolated from Lonomia achelous caterpillars haemolymph, administered either as a single intravenous bolus or as a continuous infusion, was evaluated in a rabbit jugular vein thrombosis model, and compared with those of single-chain tissue-type plasminogen activator (sct-PA) and two-chain urokinase-type plasminogen activator (tcu-PA). As a bolus LV, at doses of 100 000 IU/kg body weight (bw) produced an activator-induced thrombolysis (AIL) of 50.94% +/- 12.4 compared with 14.4% +/- 10.8 for tcu-PA at the same dose. As a continuous infusion at doses of 200 000 IU/kg bw LV produced an AIL of 45.8%, whereas sct-PA and tcu-PA produced an AIL of 69.9 and 33.7%, respectively. Fibrinogen, plasminogen and alpha-2-antiplasmin levels decreased significantly with the higher doses of LV, sct-PA, and tcu-PA. Factor XIII levels were significantly reduced in a dose-dependent manner only with LV. In conclusion, LV produces a dose-dependent thrombolysis in combination with a decrease in factor XIII activity.

Inducible nitric oxide synthase (iNOS) expression in liver and splenic T lymphocyte rise are associated with liver histological damage during experimental hepatitis A virus (HAV) infection in Callithrix jacchus.

Callithrix jacchus is considered a reliable animal model for hepatitis A virus (HAV) infection. All three HAV orally inoculated marmosets developed hepatitis - the infection was monitored by continuous virus shedding, high levels of serum enzyme alanine aminotransferase, specific antibody and seroconversion 3-6 weeks after HAV inoculation. HAV antigen was detected in liver by immunofluorescence 4 days post inoculation (PI) and onwards. To gain insight into the biological role of inducible nitric oxide synthase (iNOS) during immune-related acute liver injury the enzyme was searched in frozen biopsies: immunofluorescent labeling was found in the cytoplasm of liver cells mainly Kupffer's cells and spleen macrophages (CD68+) starting 11 days PI with maximum intensity on the fifth to sixth week PI. Necroinflammatory liver lesions characteristic of viral hepatitis were also observed at 10 days PI with maximum severity at 4 to 6 weeks PI. Furthermore, T lymphocytes (CD2+) were raised at this time point. No difference was evident in the frequency of B lymphocytes (CD20+). Therefore, iNOS expression preceded necroinflammatory liver lesion and maximal immunofluorescence reaction was coincident with tissue injury, supporting the hypothesis that NO contributes to hepatic cytotoxic mechanism but also to virus clearance. The concomitant rise in T-lymphocyte population may suggest a role for these cells in this and/or other independent HAV-induced pathological changes.

Intercomparison of calibration procedures for 192Ir HDR sources in Brazil.

The lack of well established dosimetry protocols for HDR sources is a point of great concern regarding the uniformity of procedures within a particular country and worldwide. The main objective of this paper is to report the results from ten institutions of an intercomparison of calibration procedures for 192Ir HDR sources currently in use in Brazil. The treatment irradiator of one institution was calibrated by a reference system and used by all participants with their own measuring electrometers and ionization chambers under the same experimental conditions. Two methods were used: the calibration jig and the well-type ionization chamber. Each participant was allowed to use their own method and formalism. The results of this exercise were very positive since this was the first time in Brazil that a group of users gathered to share their experience and openly discuss the physical concepts behind the calibration procedures. The results were all within +/-3.0%, except one case where -4.6% was observed and later identified as a problem with the Nk value for x-rays. Though the magnitude of the deviations found was generally acceptable considering the diversity of formalisms currently in use, a proposal is now being prepared to be adopted as a national protocol. The identification of the institutions was left out for the sake of confidentiality.

Early infarct artery collateral flow does not improve long-term survival following thrombolytic therapy for acute myocardial infarction.

It is known that acutely developed collaterals can prevent the onset of acute myocardial infarction (AMI) in the presence of a total coronary occlusion. However, there still is controversy concerning long-term follow-up of coronary collateral circulation to the infarct-related artery. In this study we analyze the prognostic role of collateral flow (degrees 0 to 3) as well as anterograde flow (degrees 0 to 3) in patients with AMI treated with thrombolytic therapy. Four hundred twenty-two patients (median age 57 years, 355 men) with AMI were treated with intravenous streptokinase and followed prospectively for up to 8 years. At the end of the study period, patients with collateral coronary flow 3 (n = 30) and those with flow <3 (n = 392) at in-hospital coronary arteriography had survival rates of 66% and 85%, respectively (p <0.12). Meanwhile, patients with coronary anterograde flow 3 (n = 189) and those with flow <3 (n = 233) had survival rates of 89% and 80%, respectively (p <0.04). By censored regression analysis, a negative correlation was found between coronary collateral flow degree and survival (p = 0.0498) and, inversely, a positive correlation was found between coronary anterograde flow degree and survival (p = 0.0053). By Cox multivariate analysis, the following variables showed significant correlations with long-term survival: global left ventricular ejection fraction (p = 0.0003), anterograde flow degree (p = 0.0006), collateral flow degree (negative correlation, p = 0.0179), and medical treatment (negative correlation, p = 0.0464). Thus, patients treated with intravenous streptokinase during AMI and with adequate coronary collateral circulation had a worse prognosis than those who developed adequate anterograde flow, probably because of residual myocardial ischemia. Such patients may benefit from coronary revascularization (angioplasty or surgery) to restore anterograde blood flow and minimize myocardium at risk.

[Differences between knowledge and attitudes to AIDS in adolescents]. / Diferencias entre conocimientos y actitudes frente al sida en población adolescente.

OBJECTIVES: To relate knowledge about AIDS to the worry and fear caused by normal everyday situations, in which someone seropositive or with AIDS is involved, but when the virus cannot be transmitted. To find the discrimination that exists towards HIV carriers and people with AIDS. DESIGN: A basically descriptive crossover observation study. SETTING: Educational centres in the city of Castellón. PARTICIPANTS: 628 adolescents found by multi-stage conglomerate sampling. MEASUREMENTS AND RESULTS: A self-filled questionnaire was used. The items involving behaviour through which the virus was not transmitted, and for which the knowledge, worry and fear generated were evaluated, were described analytically. Items concerning discriminatory attitudes were analysed. Although we detected a lack of knowledge, the worry and fear generated by each situation was greater. In over 75% of those polled we observed discriminatory attitudes. CONCLUSIONS: We detected important divergences between knowledge about paths of non-transmission, and the anxiety and fear generated. Perhaps the preventive campaigns have contributed knowledge about the paths of contagion, but it is clear that they have not helped to modify discriminatory attitudes towards people with HIV or AIDS.

The role of antegrade and collateral flow in relation to left ventricular function post-thrombolysis.

UNLABELLED: The aim of the study was to analyze the relationship between antegrade and collateral flow degree to the "culprit" coronary artery, and between both variables and left ventricular systolic function. We analyzed five hundred patients with acute myocardial infarction, treated prospectively and consecutively within 6 h of evolution with intravenous streptokinase. The degree of antegrade (0-3) and collateral blood flow (0-3) were correlated with 18 other variables. RESULTS: (a) By simple regression analysis, antegrade flow degree correlated positively (p < 0.0001), and collateral flow degree negatively (p = 0.0073) with left ventricular ejection fraction; (b) By multiple regression analysis, antegrade flow degree (p = 0.0032), but not collateral flow degree (p > 0.1), correlated independently with left ventricular ejection fraction; (c) In the subgroup of patients with occluded "culprit" coronary artery, the mean ejection fraction was significantly higher for those with collateral flow 3 (60.2% +/- 13.3 in relation to those with collateral flow < 3 (53.9% +/- 13.1, p = 0.032, 95% CI. 11.96 to (0.53%). In conclusion, antegrade coronary flow degree, but not collateral flow degree, correlated significantly and independently with left ventricular ejection fraction. However, in the subgroup of patients with occluded "culprit" coronary artery, collateral flow 3 led to better left ventricular systolic function, in relation to collateral flow < 3.

Diltiazem improves left ventricular systolic function following acute myocardial infarction treated with streptokinase. The Calcium Antagonist in Reperfusion Study (CARES) Group.

The role of diltiazem on left ventricular systolic function was analyzed in 101 patients with acute myocardial infarction treated with streptokinase, being obtained, for the total of the population, higher LV global ejection fraction (p = 0.022), LV regional shortening (p = 0.046) and LV global shortening (p = 0.064) for the treated group, relative to the placebo group; the p values were, respectively, 0.005, 0.009, and 0.012, for patients that achieved TIMI-3 antegrade coronary flow. It is concluded that diltiazem is useful as adjuvant to streptokinase, especially when antegrade coronary blood flow TIMI-3 is obtained.