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The arbuscular mycorrhizal symbiosis, a key component of agroecosystems, was assayed as a rhizosphere biosensor for evaluation of the impact of certain antifungal Pseudomonas inoculants used to control soil-borne plant pathogens. The following three Pseudomonas strains were tested: wild-type strain F113, which produces the antifungal compound 2,4-diacetylphloroglucinol (DAPG); strain F113G22, a DAPG-negative mutant of F113; and strain F113(pCU203), a DAPG overproducer. Wild-type strain F113 and mutant strain F113G22 stimulated both mycelial development from Glomus mosseae spores germinating in soil and tomato root colonization. Strain F113(pCU203) did not adversely affect G. mosseae performance. Mycelial development, but not spore germination, is sensitive to 10 &mgr;M DAPG, a concentration that might be present in the rhizosphere. The results of scanning electron and confocal microscopy demonstrated that strain F113 and its derivatives adhered to G. mosseae spores independent of the ability to produce DAPG.

As liver can be an important target organ in malaria, we performed an ultrastructural study of hepatic alterations in the final stage of Plasmodium berghei infection in mice. Significant hepatocyte abnormalities were found. An elevated number of cells showed mitochondria with a high electron-dense matrix and multiple changes in shape and size, alterations in the structure of Golgi complex, swelling and disorganisation of both rough and smooth-surfaced endoplasmic reticulum, differently shaped peroxisome nucleoids, and disappearance of glycogen granules. In other areas the hepatocytes were significantly altered with diminished microvilli and exhibited myelin-like figures, autophagic vacuoles, abundant lipid droplets, and swollen mitochondria in their cytoplasm. Necrotic and atrophied hepatocytes with scarce microvilli in the Disse space and biliary canaliculi could be seen. Parasitised red blood cells and parasite debris were found inside degenerated hepatocytes. Alterations were also noticed in microvasculature, including thickened endothelial cells with swollen mitochondria, lysosomes and autophagic vacuoles in their cytoplasm. Our results demonstrate that hepatocyte damage is an important finding associated with the advanced stages of P. berghei malarial infection, which may lead to liver dysfunction in this disease.

This work was designed to verify if a simple quantitative procedure to estimate the state of collagen aggregation is useful in describing the natural history of a fibrous process. For this purpose sixteen cases of Lechiguana lesion were used. Histochemical evaluation of the collagen content and its state of aggregation was done by the Picrosirius-polarization method. Morphometric studies were done by means of a point-counting procedure, which allowed the determination of the areal fraction of thin and thick collagenous fibers within Lechiguana lesions collected at different times of clinical evolution (14 days through 8 months). Early lesions are characterized by thin collagenous fibers. This population of slender fibers decreases later on, when thick fibers become more prevalent. Curve fitting procedures were employed using the state of collagen aggregation as the dependent variable and time as the independent variable. The best fitting was obtained by linear and exponential functions. Statistical analysis indicates that the quantitative study of the degree of collagen organization allows an adequate determination of the time course of Lechiguana lesions. We concluded that simple determinations of collagen aggregation provide numerical data that may be useful to build mathematical models relating time of evolution of the disease to fibrosis.

The age distribution of antibody to simian rotavirus (SA-11) was studied in serum specimens obtained from 399 children aged to 5 years and living in the city of Recife (PE), located in the north eastern region of Brazil. Sera were examined for group-specific rotavirus antibody using a blocking enzyme immunoassay (bELISA) and a hemagglutination inhibition antibody (HIA) test, and for anti-VP2, anti-VP4, anti-VP6, and anti-VP7 antibodies using an immunoblotting assay (IBA). Antibody prevalence was similar in all bELISA and HIA assays, showing a steep rise in the 6-to 17-month-old age groups. The results indicate early acquisition of antibody to rotavirus. The majority of children aged 2 to 4 years had bELISA (50% to 60%) and HIA (70% to 81%) antibodies. There was an association in prevalence data obtained by HIA and bELISA with immunoblotting (IBA), revealing four serologic profiles. Children with profiles I and II (60%) respectively had HAI and ELISA antibody or HAI antibody alone and all had immunoprotective antibodies to VP4 and/or VP7. These children were regarded as "immune," resembling convalescent patients with a rotavirus infection. Children with profile III (4%) had no HIA antibody and only non-protective anti-VP6 and/or VP7 antibody, and were considered to be "partially immune." Children with profile IV (36%) had no detectable antibody and were classified as "nonimmune." These children should be considered to be susceptible to rotavirus infection, with the risk of developing clinically severe diarrhea.

Multidrug-resistant tuberculosis (MDRTB) has emerged as a major public health problem worldwide. To determine the incidence and risk factors associated with tuberculosis among contacts of MDRTB index cases, we studied human immunodeficiency virus-seronegative close contacts of 64 culture-confirmed MDRTB patients in Rio de Janeiro, Brazil. Between March 1988 and July 1992, tuberculosis developed in 17 (7.8%) of 218 previously healthy close contacts of 64 MDRTB index cases (1.6 cases per 1,000-person-months of contact). Among strains of Mycobacterium tuberculosis isolated from 13 contacts of 12 index cases, six (46%) had susceptibility patterns identical to those of their index cases, four (31%) had different patterns of resistance, and three (23%) were susceptible to all drugs. Tuberculosis developed more frequently in male contacts (p < 0.05), persons > or = 15 yr of age (p < 0.05), nonwhites (p < 0.001), and persons not previously vaccinated with bacillus Calmette-Guerin (BCG) (p < 0.05). The association of BCG vaccination with decreased risk of disease was significant even when this variable was controlled (by Cox's regression analysis) for age, sex, race, purified protein derivative (PPD) status, and isoniazid prophylaxis. BCG vaccination appears to offer protection against tuberculosis during prolonged exposures to persons with MDRTB, which identifies a novel and specific indication of BCG use.

The seroprevalence of human T cell leukemia virus type 1 (HTLV-1) infection was investigated in Brazilians (570): native inhabitants (298) and descendants from Japanese (272) living in Recife and its neighborhoods--North-east of Brazil. Furthermore, polytransfused renal transplanted patients (54) were also examined for the serological status to this virus. The seropositivity to HTLV-1, screened by enzyme-linked immunosorbent assay (ELISA), was low: 1.34% for the local population and 0.73% for the descendants from Japanese. However, the seropositivity for the renal transplanted patients was found to be 11.1%. This higher value suggests that this retrovirus infection seems to be of importance in this clinical condition.

This paper presents several experiences obtained in the Rural Research Center of the Solís Valley in relation to community participation programs. The main objective of these projects was to improve the nutritional practices of children in the rural areas of highland Mexico. As first experience, small groups were formed with mothers, fathers, married couples and teenagers. Each of these groups started a project oriented to promote nutritional self-sufficiency. One group of mothers was successful in assuring the provision of government subsidized milk in their community. A second group of mothers started a chicken-raising farm, but the project failed because all the chicken died in an epidemic. The group of fathers started a sheep-raising project as the first step to get a milk-producing cow. The sheep-raising was successful, but when the sheep were sold each man in the group kept the revenue to himself and the group disappeared. The married couples were successful both in a home-gardening project and in a chicken-raising farm. The teenagers were also successful with their home-gardening project and acted as "injection groups" to spread the project in other communities. As a second experience in community participation, community health workers taught mothers how to use locally available food to improve their diets, preparing culturally acceptable food recipes. This intervention was successful in increasing mother's awareness of a balanced diet. A second intervention combined the presentation of a drama ("peasant's theater") in order to increase mother's participation in these projects.(ABSTRACT TRUNCATED AT 250 WORDS)

We studied 567 patients with active pulmonary tuberculosis (APT) in Rio de Janeiro, Brazil, by using a standardized questionnaire and by testing blood for HIV antibodies. The rate of HIV infection was 3.9% in 1987, 4.8% in 1988, and 5.2% in 1989, and did not differ by sex. It was highest (7.4%) in the 15- to 39-year age group. There was no difference between patients infected and not infected by HIV with regard to education, income, housing, or employment. Among all patients with definite HIV risk behavior, the HIV infection rate was 23.3%, rising to 31.2% among homo/bisexual men and 36.4% among intravenous drug users, and the rate was 6.5% for blood-transfusion recipients. Among patients who denied risk behavior, the rate was 1.2%. Generalized lymphadenopathy and oral candidiasis occurred with greater frequency among HIV-infected patients (p < 0.0001). Applying the World Health Organization 1985 clinical criteria and revised case definition for AIDS, we found, respectively, sensitivities of 34% and 76.9% and specificities of 31% and 26.3%; in the Rio de Janeiro environment, these clinical criteria without HIV serology should not be adopted for tuberculosis patients. For chest radiographs, a significant association was found between HIV infection and the occurrence of atypical images (p = 0.0001), and hilar and/or mediastinal adenopathy (p = 0.0002) and absence of cavities (p = 0.0003). A PPD (purified protein derivative) skin test induration of < 5 mm was identified in 53% of the HIV-positive cases and in 31.3% of the HIV-negative cases. Only 11.5% of HIV-infected APT patients met the Centers for Disease Control 1987 AIDS criteria.

The seroprevalence of antibodies against cytomegalovirus (CMV), human herpesvirus 6 (HHV-6) and human T cell leukemia virus type 1 (HTLV-1), determined by ELISA and by fluorescence in 54 renal transplanted patients, was 96.2%, 88.8% and 11.1%, respectively. These values are relatively high when compared with the results obtained for healthy individuals of the same age groups from Recife, Northeastern Brazil. Active CMV infection was detected by the presence of IgM antibodies and/or virus isolation in 13 (24%) patients. Kidney rejection and renal dysfunction were observed in 11 of these 13 patients, whereas 3 of 6 HTLV-1 antibody-positive individuals presented these complications. All HTLV-1 positive patients were also positive to IgG CMV and HHV-6 antibodies. The importance of the three viruses in this clinical condition is suggested by the high seropositivity rates compared with the healthy population. The group may also represent a potential source of HTLV-1 infection in this non-endemic area.

1. We have investigated the possibility that proteinases released by Candida albicans participate in the early killing of three types of mice peritoneal macrophage (resident, thioglycollate-elicited, or Con A-activated) in vitro. 2. Phagocytic assays were performed by incubation of macrophages and C. albicans together at a 1:10 ratio for 30 min at 37 degrees C in RPMI medium buffered to pH 7.0 with 12 mM Hepes without serum. With no albumin added to the medium, the macrophages were 85% to 100% damaged and unviable, to a greater extent than expected from the proportion of phagocytic cells containing germ tubes. When 10 mg/ml of albumin was added to the medium, however, 90% of the macrophages remained viable for the 2 hours of the phagocytic assay, suggesting that albumin may have acted as a substrate for or inhibitor of proteinases released by C. albicans, thereby protecting the macrophage from the proteolytic action of the proteinases. 3. The phagocytosis of IgG-coated erythrocytes was reduced to 43% when IgG was preincubated with the supernatant from C. albicans cultures, but the addition of 10 mg/ml albumin or of 5 micrograms/ml pepstatin (an inhibitor of C. albicans acid proteinases) to the same supernatants prevented the effect on phagocytosis of IgG-coated erythrocytes. 4. These results suggest that proteinases released from C. albicans are involved in the early killing of macrophages.

The effects of misoprostol and cimetidine on diazepam pharmacokinetics were evaluated in order to determine whether the kinetic variables for diazepam and nordiazepam alone differ with the repeated oral administration of misoprostol and cimetidine to healthy adult volunteers. The trial was conducted as an open crossover study in 12 normal subjects, divided into two groups with all subjects receiving both regimens. Total study duration was 5 weeks. An initial clinical assessment, including blood biochemistry and assessment of subject oxidation status was carried out on study day 1. On this day, subjects began taking diazepam (10 mg) orally for one week, with pharmacokinetic studies performed at day 8, when steady state levels of diazepam were reached. This was followed by one week with active drug, misoprostol to Group I and cimetidine to Group II, with pharmacokinetic studies performed at the end of a 1-week treatment. After a 2-week wash-out period, both groups took for one week, the alternate drug, i.e. cimetidine plus diazepam to Group I and misoprostol plus diazepam to Group II. On days 8, 15 and 36, subjects were admitted to the hospital for 12 h, during which time a clinical examination was carried out and blood samples were taken at time zero and at 4, 8, 12, 24, and 36 h post-dosing for the measurement of serum diazepam and nordiazepam. The main parameters measured and evaluated were diazepam and nordiazepam pharmacokinetics at steady state (days 8, 15 and 36). These were areas under the curve in the dose intervals (AUC0-24h), maximum plasma concentrations (Cmax), time to peak concentrations (Tmax), elimination half-life (t1/2), elimination constant (Kel), distribution volume (Vd), total body clearance (ClB) and clearance after oral administration (Cloral). The results demonstrated that plasma diazepam and nordiazepam concentrations had a significant increase after steady states have been reached with the simultaneous administration of 800 mg of cimetidine daily for one week. The simultaneous administration of 800 micrograms of misoprostol did not cause any significant change in diazepam and nordiazepam plasma levels after steady states had been reached. Comparing the pharmacokinetic parameters of Groups A and B as well as within groups on days 8, 15 and 36, a significant increase in plasma diazepam and nordiazepam levels was detected. This was due to a cimetidine-induced impairment in microsomal oxidation of diazepam and nordiazepam, which caused a decrease in total metabolic clearance and increased mean steady state plasma concentrations. A more prolonged half-life was observed for both groups taking cimetidine as well as an increase of mean maximum plasma concentrations.(ABSTRACT TRUNCATED AT 400 WORDS)

The serological status to cytomegalovirus (CMV) was examined for 616 Brazilians and 399 Japanese immigrants living in the North-East of Brazil. The sera were screened for IgG antibodies to CMV by enzyme-linked immunosorbent assay (ELISA). The overall prevalence of CMV antibodies was higher in the Japanese population (83.7%) than in the Brazilian population (69.8%). The seropositivity was analyzed by factors of age, sex, ethnic background, and socioeconomic status. Mother-baby contact seems to be a factor of significance in the seroepidemiology of CMV infection.

A case of chondrosarcoma of the orbit is reported. The patient complained of marked deterioration of her vision, pain and presented exophatalmus of the left eye. Chondrosarcoma of the orbit are rare and this is the first case reported in the Brazilian literature. Diagnostic and prognostic are discussed.

One hundred and twelve asymptomatic individuals were analysed with regard to the simultaneous incidence of Staphylococcus aureus on their hands and in their nose, mouth and stools, in the city of S. Paulo (Brazil). A total of 40 (35.7%) individuals were detected as carriers of this microorganism. Among these carriers, 27 (67.5%) were positive in only one of the four niches studied, 8 (20.0%) in two and 5 (12.5%) in three niches. They were identified 113 Staphylococcus aureus strains, and 28 (24.8%) of these strains, isolated from 9 (22.5%) carriers, produced enterotoxin. Of these strains, 7 (25.0%) produced type A enterotoxin, 6 (21.4%) of type B, 11 (39.3%) type C and 4 (14.3%) produced both type A and C. The phage typing of the 113 Staphylococcus aureus strains revealed the predominance of the strains lysed by phages belonging to the Group I/III/NC (16.8%). The results obtained did not demonstrate the simultaneous incidence of Staphylococcus aureus strains in samples collected from mouth, hands and stools of the group studied.