Resistance Sources and Antixenotic Factors in Brazilian Bean Genotypes Against Bemisia tabaci.

Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Middle East Asia Minor 1 is one of the most important pests of the common bean, due to its potential of causing direct and indirect damage. This study aimed to evaluate 78 bean genotypes to verify the occurrence of resistance of antixenosis type against B. tabaci. Initially, multiple-choice trials were performed to evaluate the oviposition preference and nymphs' establishment at 3 and 15 days after infestation. Subsequently, 21 bean genotypes were selected, and a no-choice test was conducted. Colorimetric analyses were performed to establish correlations between leaf color and insect establishment. In multiple-choice trial, the genotypes BRS Ametista, BRS Estilo, BRS Esplendor, SCS 204 Predileto, BRS Notável, IPR Eldorado, CHIB 06, IPR Quero-Quero, Iapar 81, CHIP 338, IPR Garça, Arcelina 4, SCS 202 Guará, IAC Esperança, H96102-1-1-1-52, CHIP 348, Carioca Comum, CHIP 300, IAC Carioca Eté, IAC Ybaté, and Tybatã were the least used for oviposition and nymph establishment, demonstrating antixenosis or antibiosis. In the no-choice trial, most genotypes were less attractive to whitefly, and the genotypes CHIB 06, IPR Garça, CHIP 300, and IAC Esperança had less oviposition. The most attractive genotypes presented high luminosity and more intense green and yellow colors, indicating positive correlation. Therefore, the genotypes BRS Ametista, SCS 204 Predileto, BRS Estilo, IPR Eldorado, SCS-202 Guará, Carioca Comum, Arcelina 4, CHIP 348, and IAC Esperança showed the highest resistance stability in the no-choice trial, and they are promising sources of antixenotic factors for use in breeding programs to obtain whitefly-resistant common bean lines.

Hepatitis B virus and hepatitis delta virus genotypes in outbreaks of fulminant hepatitis (Labrea black fever) in the western Brazilian Amazon region.

The genotypes of hepatitis B (HBV) and delta (HDV) viruses circulating among fulminant hepatitis cases from the western Amazon Basin of Brazil were characterized in this study. HBV and HDV isolates were obtained from liver samples from 14 patients who developed fulminant hepatitis and died during 1978-1989. HBV DNA and HDV RNA were detected in all samples. Phylogenetic analyses of HDV sequences showed that they all clustered with previously characterized sequences of HDV genotype 3 (HDV-3). HBV genotypes F, A and D were found in 50.0, 28.6 and 21.4 % of cases, respectively. These results confirm the predominance of HDV-3 in South America and its association with the severe form of hepatitis, and the finding of the co-infection of HDV-3 with different genotypes of HBV suggests that the association between HDV-3 and HBV-F is not necessarily causally related to a more severe clinical course of infection.

Crop beta-glucanase activity limits the effectiveness of a recombinant cellulase used to supplement a barley-based feed for free-range broilers.

1. The supplementation of diets rich in soluble polysaccharides with microbial cellulases and hemicellulases decreases digesta viscosity and promotes broiler performance. 2. In contrast, recent experiments suggest that polysaccharidases are ineffective for improving the nutritive value of pasture biomass used by free-range broilers. However, the feasibility of using cellulases and hemicellulases to improve the utilisation of cereal-based feeds by pastured poultry remains to be established. 3. A study was undertaken to investigate the capacity of a recombinant cellulase from Clostridium thermocellum to improve the nutritive value of a barley-based feed for free-range pastured broilers of the RedBro Cou Nu x RedBro M genotype. 4. The results show that supplementation of a barley-based diet with a recombinant beta-glucanase had no effect on the performance of free-range broilers, foraging in legume-based diets from d 28 to 56. In addition, the results confirm that the lack of effect of the recombinant enzyme in improving the nutritive value of the barley-based feed does not result from enzyme proteolysis or inhibition in the gastrointestinal tract. 5. Significantly, beta-glucanase activity was identified in the crop of non-supplemented animals. The data suggest that endogenous cellulases originated both from the barley-based feed and from the crop microflora. 6. The results presented here suggest that in older birds of slow-growing genotypes associated with free-range production systems, previously unknown sources of beta-glucanases, such as the feed and microbial symbiotic microflora, can affect the effectiveness of exogenous enzymes added to the feed.

Obese obstructive sleep apnea patients with tonsil hypertrophy submitted to tonsillectomy.

The physiopathology of obstructive sleep apnea-hypopnea syndrome (OSAHS) is multifactorial and obesity has been shown to be one of the main factors correlated with its occurrence. In obese patients with anatomical alterations of the upper airways it is often difficult to predict success for surgical correction since obesity is a limiting factor. Therefore, the aim of the present study was to evaluate the results of tonsillectomy in a specific group of patients, i.e., obese OSAHS patients with tonsil hypertrophy. Seven OSAHS patients with moderate obesity with obstructive palatine tonsil hypertrophy were submitted to tonsillectomy. All patients were submitted to pre- and postoperative appraisal of body mass index, otorhinolaryngology examination and polysomnography. Patients' average age was 36.4 +/- 10.3 years and average preoperative body mass index was 36.6 +/- 6.3 kg/m(2). Postoperative weight did not differ significantly from preoperative weight (P = 0.27). Average preoperative apnea and hypopnea index (AHI) was 81 +/- 26/h and postoperative AHI was 23 +/- 18/h (P = 0.0005). Average preoperative minimum oxyhemoglobin saturation (SaO2 min) was 69 +/- 14% and the postoperative value was 83 +/- 3% (P = 0.038). In relation to AHI, 6 (86%) of the 7 patients studied showed a reduction of 50% in relation to preoperative level and of these, 4 (57%) presented AHI of less than 20%. Only one patient presented a reduction of less than 50% in AHI, but even so showed improved SaO2 min. Tonsillectomy treatment for OSAHS in obese patients with obstructive palatine tonsil hypertrophy caused a significant reduction in AHI, with improvement in SaO2 min. This procedure could be eventually considered as an option of treatment for obese OSAHS patients with significant tonsil hypertrophy when continuous positive air pressure therapy is not possible as the first choice of treatment.

Detection of virulence-associated genes in pathogenic and commensal avian Escherichia coli isolates.

Poultry colibacillosis due to Avian Pathogenic Escherichia coli (APEC) is responsible for several extra-intestinal pathological conditions, leading to serious economic damage in poultry production. The most commonly associated pathologies are airsacculitis, colisepticemia, and cellulitis in broiler chickens, and salpingitis and peritonitis in broiler breeders. In this work a total of 66 strains isolated from dead broiler breeders affected with colibacillosis and 61 strains from healthy broilers were studied. Strains from broiler breeders were typified with serogroups O2, O18, and O78, which are mainly associated with disease. The serogroup O78 was the most prevalent (58%). All the strains were checked for the presence of 11 virulence genes: 1) arginine succinyltransferase A (astA); ii) E.coli hemeutilization protein A (chuA); iii) colicin V A/B (cvaA/B); iv) fimbriae mannose-binding type 1 (fimC); v) ferric yersiniabactin uptake A (fyuA); vi) iron-repressible high-molecular-weight proteins 2 (irp2); vii) increased serum survival (iss); viii) iron-uptake systems of E.coli D (iucD); ix) pielonefritis associated to pili C (papC); x) temperature sensitive haemaglutinin (tsh), and xi) vacuolating autotransporter toxin (vat), by Multiplex-PCR. The results showed that all genes are present in both commensal and pathogenic E. coli strains. The iron uptake-related genes and the serum survival gene were more prevalent among APEC. The adhesin genes, except tsh, and the toxin genes, except astA, were also more prevalent among APEC isolates. Except for astA and tsh, APEC strains harbored the majority of the virulence-associated genes studied and fimC was the most prevalent gene, detected in 96.97 and 88.52% of APEC and AFEC strains, respectively. Possession of more than one iron transport system seems to play an important role on APEC survival.

TST reversion in a BCG-revaccinated population of nursing and medical students, São Paulo, Brazil, 1997-2000.

SETTING: A major university in São Paulo, Brazil, where vaccination against tuberculosis (TB) with bacille Calmette-Guerin (BCG) was routinely offered to first-year medical and nursing students. OBJECTIVES: To estimate the probability of negative tuberculin skin test (TST) results over a 4-year period following BCG revaccination, and to evaluate the effect of factors associated with reversion. DESIGN: Students were enrolled in 1997, initially given a two-step TST, and were retested annually or biannually for the duration of the study. Data on TB exposures and potential risk factors for TST negativity and reversion were collected through annual surveys. A linear mixture survival model was used to estimate the probability of negative TST results over time. RESULTS: Of 159 students, an estimated 20% had a negative TST result despite revaccination, and a further 31% reverted to negative over 4 years of follow-up. No cofactors significantly affected the probability of reversion. CONCLUSION: Overall, in the absence of reported exposure to Mycobacterium tuberculosis, 51% of students revaccinated upon entering nursing or medical school would have a negative TST result by the time they begin their internships. In this recently vaccinated population, reversion was common, suggesting that annual TST screening may remain a useful tool.

Eucalyptol, an essential oil, reduces contractile activity in rat cardiac muscle.

Eucalyptol is an essential oil that relaxes bronchial and vascular smooth muscle although its direct actions on isolated myocardium have not been reported. We investigated a putative negative inotropic effect of the oil on left ventricular papillary muscles from male Wistar rats weighing 250 to 300 g, as well as its effects on isometric force, rate of force development, time parameters, post-rest potentiation, positive inotropic interventions produced by Ca2+ and isoproterenol, and on tetanic tension. The effects of 0.3 mM eucalyptol on myosin ATPase activity were also investigated. Eucalyptol (0.003 to 0.3 mM) reduced isometric tension, the rate of force development and time parameters. The oil reduced the force developed by steady-state contractions (50% at 0.3 mM) but did not alter sarcoplasmic reticulum function or post-rest contractions and produced a progressive increase in relative potentiation. Increased extracellular Ca2+ concentration (0.62 to 5 mM) and isoproterenol (20 nM) administration counteracted the negative inotropic effects of the oil. The activity of the contractile machinery evaluated by tetanic force development was reduced by 30 to 50% but myosin ATPase activity was not affected by eucalyptol (0.3 mM), supporting the idea of a reduction of sarcolemmal Ca2+ influx. The present results suggest that eucalyptol depresses force development, probably acting as a calcium channel blocker.

Ovine chorionic somatomammotrophin (oCS) production by isolated cotyledon cells from sheep in early and mid gestation: auto-regulation by recombinant oCS.

We report the ability of sheep placental cotyledonary cells, isolated at different periods of pregnancy (40 to 90 days) to produce ovine chorionic somatomammotrophin (oCS) in in vitro culture conditions. This oCS production increased gradually with stage of pregnancy. Endogenous oCS net production by isolated placental cells was increased, in a dose-dependent manner, by addition of recombinant oCS (roCS). This effect was not observed after addition of recombinant ovine growth hormone. The roCS effect was more potent on cells collected during early pregnancy. Specific immunoprecipitation of oCS revealed that roCS treatment was associated with an increased dose-dependent incorporation of [35S]methionine-[35S]cysteine. These findings provide evidence that oCS may act in a paracrine/autocrine manner to up-regulate its own production during early gestation. We suggest that this autoregulation may be associated with morphological and functional differentiation of the trophoblast during the growth of the placenta.

Prevalence of the mutation C677 --> T in the methylene tetrahydrofolate reductase gene among distinct ethnic groups in Brazil.

Vascular disease is a serious public health problem in the industrialized world, and is a frequent cause of death among the adult population of Brazil. Mild hyperhomocysteinemia has been identified as a risk factor for arterial disease, venous thrombosis, and neural tube defects. Individuals homozygous for the thermolabile variant of methylenetetrahydrofolate reductase (MTHFR-T) are found in 5-15% of the general population and have significantly elevated plasma homocysteine levels which represent one of the genetic risk factors for vascular diseases. We have analyzed the prevalence of individuals homozygous for the MTHFR-T in 327 subjects representing the three distinct ethnic groups in Brazil. The prevalence of homozygotes for the mutated allele MTHFR-T was high among persons of Caucasian descent (10%) and considerably lower among Black (1.45%) and Indians persons populations (1.2%). These data suggest that screening for the MTHFR-T allele should help in identifying individuals with a high risk of vascular disease among populations with a heterogeneous background.

Interferon induction in mouse fibroblast L-A9 cells.

Mouse L-A9 cell interferon was induced by infection with Newcastle disease virus. Interferon production was 1.5 X 10(5) IU/10(7) cells. Interferon was partially purified by precipitation with ammonium sulphate, chromatography on CM-Sephadex and hydrophobic chromatography on octyl-agarose. The specific activity of the final preparation was 1.7 X 10(7) IU/mg protein. Treatment of L-A9 cells with 20 IU/ml interferon prior to viral infection inhibited the intracellular accumulation of reovirus-specific double-stranded RNA. Dose-response studies of the cells to interferon indicated that L-A9 cells require 10, 13 and 15 IU/ml to obtain 50% viral plaque reduction for Marituba virus, vesicular stomatitis virus and reovirus, respectively. The present results demonstrate the potential of mouse L-A9 cells as an interferon-producing system and also as a model for the study of the effect of cellular response to exogenous interferon treatment on the replication of RNA viruses.

Seroprevalence of hepatitis B and C in the Western Brazilian Amazon region (Rio Branco, Acre): a pilot study carried out during a hepatitis B vaccination program.

In 1999, on the occasion of the application of the first vaccine dose during the state vaccination campaign against hepatitis B virus (HBV), 390 individuals from the town of Rio Branco, Acre, aged two or more years were selected for the determination of the seroprevalence of HBV and HCV. HBV markers (HBsAg, anti-HBs, and anti-HBc IgG) were determined on this occasion and anti-HBs antibodies were also assessed 30 days after the third vaccine dose. At the time of vaccination, 39% of the individuals were still susceptible to HBV, while 61% presented serologic evidence of previous HBV contact or previous vaccination. The individuals with previous HBV contact were significantly older (p<0.001) than those without HBV markers. Of the 192 individuals who returned for reexamination, 30 days after the third dose, 158 (82.3%) had received three vaccine doses, and only 60 (31.2%) belonged to the group without HBV markers. In these individuals, the seroconversion rate after the third dose was 92% (55/60). In conclusion, we found considerable HBV in this population, indicating the need for pursuing the immunization programs. We also found high rates of vaccination coverage in the Western Brazilian Amazon region.

Transfusion-transmitted virus (TTV) in Brazil. Preliminary report.

TTV is a recently discovered DNA virus, isolated from a patient with post-transfusion hepatitis of unknown etiology by Japanese researchers. In the present study, we evaluated the presence of TTV among chronic liver diseases patients in São Paulo and Pará states, representing two geographically distinct Brazilian regions. TTV DNA was found in 21/105 (20%) and 9/20 (45%) cases from São Paulo and Pará States, respectively. DNA sequence data confirmed the presence of TTV genotypes 1a and 2a, as well as other genotypes not yet described. In conclusion, TTV is present in chronic liver diseases cases from Southeast and North Brazil. However, further studies involving healthy populations are necessary before establishing any causal relationship among TTV and human hepatitis.

Effects of eggshell quality and broiler breeder age on hatchability.

The effects of eggshell quality and breeder age were assessed on egg weight loss during incubation, fertility, hatchability, and embryonic mortality. The trials involved hatching eggs from three commercial broiler breeder flocks of the same strain but of different ages. The eggs were divided according to specific gravity into two groups, thin-shelled (< or = 1.080) and thick-shelled (> 1.080). Thin-shelled eggs displayed a greater increase in weight with breeder age and greater weight loss during incubation. Thick-shelled eggs showed an increased hatchability as a result of greater fertility and lower intermediate and late embryonic mortalities. Percentage of culls, pips, and rots were not related to shell thickness. Eggs from the younger flock had a higher weight loss during incubation irrespective of shell thickness. Hatchability and viability (hatchability of fertile eggs) were lower in the younger flock due to increased early and late embryonic mortalities. Fertility, culls, and pips were not affected by breeder age. The data may indicate the extent to which recent innovations in breeder management and in incubation technology have changed patterns of fertility and embryonic mortality.

Effects of broiler breeder age and length of egg storage on albumen characteristics and hatchability.

Two experiments were conducted with the purpose of determining the influence of broiler breeder age and storage time on egg albumen characteristics, embryonic mortality, and hatchability. Eggs from four commercial flocks of the same strain (Peterson x Minibro Shaver), under the same management and nutritional regimen, were incubated after storage at 16 C and 78% relative humidity, for periods of 0 (fresh), 1, 4, or 8 d. Albumen height and albumen pH were recorded immediately prior to each setting in Experiment 1 (eggs collected from 32- and 54-wk-old flocks) and at 0, 12, 24, 38, and 60 h of incubation in Experiment 2 (eggs from 42- and 59-wk-old flocks). Overall, albumen pH was 0.95 higher in eggs stored for 8 d than in fresh eggs, but most of this increase occurred during the first 4 d of storage. At 0 d of storage, pH increased (P < 0.05) with flock age, but age differences were negligible at 8 d of storage. Albumen height decreased with hen age and storage time (P < 0.05). Embryo viability was affected by the storage length by flock age interaction, such that longer periods of storage decreased viability in all flock ages. Decreased viability was pronounced in older flocks, with regression coefficients of viability on days of storage being -0.82 and -1.92% at 32 and 59 wk of age, respectively. The detrimental effects of storage time on viability in older flocks were mostly due to an increased incidence of culls and embryonic losses at all stages. Present results suggest that declines in hatchability with presetting storage start 1 d after lay, possibly due to deterioration in egg albumen quality.

Effects of short storage conditions and broiler breeder age on hatchability, hatching time, and chick weights.

An experiment was conducted to assess how hatching performance is affected by breeder age and egg holding environment during short-term storage. Response variables analyzed were egg weight loss up to 18 d of incubation, viability (hatchability of fertile eggs), embryonic mortality, hatching time, and weight of male and female chicks, at hatching and at the end of incubation. The trials involved a total of 2,250 hatching eggs from each of two commercial broiler breeder flocks of the same strain (Avian) but of different ages (32 to 34 and 48 to 50 wk). Eggs were stored for 0, 1, or 2 d in the egg storage room or in the setter room. The hatching times of the chicks were recorded at 4-h intervals during the period from 478 to 494 h postincubation, and at 514 h, when incubation was terminated and all chicks were removed from the hatcher. In eggs from younger hens, viability was not influenced by preincubation storage; in older hens, viability of eggs not submitted to storage was higher (P < 0.05) by 3 to 6 percentage points than that of stored eggs. Hatching times were not affected by age of the hen, whereas male chicks tended to hatch, on average, about 3 h later than females. Chick weights at hatching and at removal from the hatcher were similar for both sexes, but females experienced a higher (P < 0.05) weight loss in that interval. Eggs incubated on the day of lay tended to hatch, on average, later than stored eggs (especially when compared to eggs submitted to 1 d storage), and produced heavier chicks.

Hepatitis B virus surface antigen (HBsAg) and antibody (anti-HBs) forming immune complexes in fulminant hepatitis.

This paper reports an unusual pattern of serological HBV markers and the presence of HBsAg/anti-HBs immune complexes in serum samples from two patients with fulminant hepatitis from the Brazilian Western Amazon Basin. The diagnosis was made by both serologic tests and demonstration of antigen/antibody complexes by transmission electron microscopy. Concurrent Delta virus superinfection is also discussed.

[Diagnosis of health conditions in a pan-mining community in the Tapajós River Basin, Itaituba, Par , Brazil, 1992]. / Diagnóstico das condições de saúde de uma comunidade garimpeira na regiõ o do Rio Tapajós, Itaituba, Pará, Brasil, 1992.

The purpose of this article is to describe health conditions in a pan-mining community, in particular the interaction of mercury contamination with other health problems. This study was carried out in a panning mine located on Rato Creek, a tributary of the Tapajó s River Basin in the municipality of Itaituba, State of Par The study population consisted of 223 individuals. An epidemiological questionnaire was applied, medical treatment was given, and biological specimens were collected. Testing of fecal samples showed that 96.1% of the individuals had parasites and 66.4% were anemic. Prevalence of hepatitis B virus was 85.0%, and 11 individuals (6.0%) were virus carriers (HBsAg positive). Of 186 patients tested for malaria, 65 individuals (35.0%) had the infection, of whom 34 (52.3%) were asymptomatic. Prevalence of syphillis was 41.6%. Urine mercury levels were measured in 173 individuals. Some 16 (9.2%) of those tested had mercury levels between 10 and 19 ug/l, while 9 patients (5.2%) had levels above 20 ug/l. An overview of general health conditions showed a combination of problems in individuals, who lacked adequate diagnosis, in addition to a high level of self-medication, given the absence of health facilities. In addition, these individuals are threatened by critical levels of mercury contamination. In conclusion, this article gives a general overview of health conditions in these pan-mining communities, demonstrating the multicausal nature of health conditions in the Amazon region, a fact which should be considered when planning appropriate strategies for clinical treatment.

Rede de apoio familiar à gravidez e ao parto na adolescência: uma abordagem moscoviciana / Family support network for pregnancy and childbirth in adolescence: a Moscovian approach

Objetivo: identificar as redes de apoio familiar às mulheres que vivenciaram a gestação e o parto recorrentes na adolescência. Métodos: estudo descritivo com abordagem qualitativa. Fizeram parte desta pesquisa 30 mulheres que vivenciaram a gestação e o parto recorrente na adolescência. Os dados foram coletados por meio de entrevista semiestruturada e analisados com base na Análise Textual Discursiva. Resultados: a família apresentou-se como principal fonte de apoio, a presença da mesma foi atrelada a discursos positivos, confirmando o pressuposto inicial deste estudo, de que a fragilidade na rede de apoio desencadeia, na adolescente, sentimentos negativos do processo de gestar e parir. Considerações finais: a figura materna apresentou‐se como principal rede de apoio sendo referenciada como importante suporte para a adolescente na vivência da gestação e do parto.

Objective: to identify family support networks for women who experienced recurrent gestation and childbirth during adolescence. Methods: descriptive study with a qualitative approach. Thirty women who experienced gestation and recurrent birth during adolescence were part of this study. Data were collected through a semi-structured interview and analyzed based on the Discursive Textual Analysis. Results: the family was the main source of support, its presence was linked to positive discourses, confirming the initial assumption of this study, that the fragility in the support network triggers, in the adolescent, negative feelings of the process of gestating and to give birth. Final considerations: the maternal figure was referred as the main support network for the adolescent in the experience of gestation and childbirth.