Coconut genome size determined by flow cytometry: Tall versus Dwarf types.

Coconuts (Cocos nucifera L.) are tropical palm trees that are classified into Tall and Dwarf types based on height, and both types are diploid (2n = 2x = 32 chromosomes). The reproduction mode is autogamous for Dwarf types and allogamous for Tall types. One hypothesis for the origin of the Dwarf coconut suggests that it is a Tall variant that resulted from either mutation or inbreeding, and differences in genome size between the two types would support this hypothesis. In this study, we estimated the genome sizes of 14 coconut accessions (eight Tall and six Dwarf types) using flow cytometry. Nuclei were extracted from leaf discs and stained with propidium iodide, and Pisum sativum (2C = 9.07 pg DNA) was used as an internal standard. Histograms with good resolution and low coefficients of variation (2.5 to 3.2%) were obtained. The 2C DNA content ranged from 5.72 to 5.48 pg for Tall accessions and from 5.58 to 5.52 pg for Dwarf accessions. The mean genome sizes for Tall and Dwarf specimens were 5.59 and 5.55 pg, respectively. Among all accessions, Rennel Island Tall had the highest mean DNA content (5.72 pg), whereas West African Tall had the lowest (5.48 pg). The mean coconut genome size (2C = 5.57 pg, corresponding to 2723.73 Mbp/haploid set) was classified as small. Only small differences in genome size existed among the coconut accessions, suggesting that the Dwarf type did not evolve from the Tall type.

Valuation of OSA process and folic acid addition as excess sludge minimization alternatives applied in the activated sludge process.

The aim of this study was to investigate the ability of the oxic-settling-anaerobic (OSA)-process and the folic acid addition applied in the activated sludge process to reduce the excess sludge production. The study was monitored during two distinct periods: activated sludge system with OSA-process, and activated sludge system with folic acid addition. The observed sludge yields (Yobs) were 0.30 and 0.08 kgTSS kg(-1) chemical oxygen demand (COD), control phase and OSA-process (period 1); 0.33 and 0.18 kgTSS kg(-1) COD, control phase and folic acid addition (period 2). The Yobs decreased by 73 and 45% in phases with the OSA-process and folic acid addition, respectively, compared with the control phases. The sludge minimization alternatives result in a decrease in excess sludge production, without negatively affecting the performance of the effluent treatment.

[Central nervous system tuberculosis in children: 1. Clinical and laboratorial presentation]. / Tuberculose do sistema nervoso central em crianças: 1. Apresentação clínica e laboratorial.

Tuberculosis still occupies a remarkable place as a worldwide health problem, chiefly in emerging countries, like Brazil. The central nervous system (CNS) involvement by Mycobacterium tuberculosis is one of the most feared features of disease, because of its high morbidity and mortality. This study aimed to describe some epidemiological, clinical and laboratorial aspects of 52 children in a tertiary pediatric hospital with CNS tuberculosis. At diagnosis, the majority of patients showed low age, compromised nutritional status, previous contact with bacillary individuals, delayed or absent immunization, advanced neurological signs and compatible abnormalities in cerebrospinal fluid (CSF) analysis and in radiological findings. The etiologic agent was identified by staining methods or CSF and other fluids culturing in 40% of patients. In most cases, despite of suggestive clinical, epidemiological and laboratorial picture and feasibility of patients access to health care centres, therapy was started late.

[Central nervous system tuberculosis in children: 2. Treatment and outcome]. / Tuberculose do sistema nervoso central em crianças: 2. Tratamento e evolução.

Neurologic damage is usual after central nervous system (CSN) tuberculosis recovery. Treatment is long, difficult and prone to complications. Many factors are enrolled as prognostic determinants. This study aimed to describe the treatment and outcome of 52 children with CNS tuberculosis of a tertiary pediatric hospital. All of them received standard triple drug regimen, and 41 (78.8%) received corticosteroids as adjunctive therapy. Hydrocephalus was common (28 of 41 tested), but only 8 (15.4%) patients underwent ventricular shunt surgery. Hepatotoxicity to anti tuberculosis drugs occurred in 32 (61.5%) cases, but in only 3 (9.4%) drug substitution was necessary. There were 8 (15.4%) deaths and 24 (46.1%) cases developed neurologic damage after therapy. Patients who did not receive steroids during treatment and those with advanced neurological involvement at diagnosis showed a tendency to worse prognosis.

Phenotypic and genotypic characteristics of Escherichia coli strains of non-enteropathogenic E. coli (EPEC) serogroups that carry EAE and lack the EPEC adherence factor and Shiga toxin DNA probe sequences.

This study was conducted to characterize the virulence potential of 59 Escherichia coli strains carrying EAE and lacking the enteropathogenic E. coli adherence factor and Shiga toxin probe sequences. In hybridization studies, all strains carried the locus of enterocyte effacement (LEE)-associated DNA sequences. Of the other 15 virulence DNA sequences tested, HLY was the most frequent (44.1%); 17 combinations of these sequences were found, but strains carrying EAE only (EAE profile) were the most frequent (35.6%). Except for 1 cytodetaching strain, all others adhered to HeLa and Caco-2 cells, most of which (approximately 75.0%) showed variations of the localized adherence pattern. Actin accumulation was detected in 75.9% of the nondetaching strains. Most strains had LEE, probably inserted in pheU (49.2%), and presented a nontypeable intimin (83.1%). Translocated intimin receptor-derived DNA sequences correlated with enteropathogenic and enterohemorrhagic E. coli in 61.0% and 32.0% of the strains, respectively. Thirty-five different serotypes were found. Only strains with the EAE profile were associated with diarrhea (P=.039).

Adherence patterns and adherence-related DNA sequences in Escherichia coli isolates from children with and without diarrhea in São Paulo city, Brazil.

The correlation between various adherence patterns and adherence-related DNA sequences in Escherichia coli isolates from 1- to 4-year-old children with and without diarrhea in São Paulo, Brazil, was evaluated. A total of 1,801 isolates obtained from 200 patients and 200 age-matched controls were studied. The adherence patterns found were classified as diffuse, aggregative, aggregative in a 6-h assay, aggregative predominantly in coverslips, localized, localized-like, and noncharacteristic. In general, the DNA sequences used as probes showed excellent specificities (>93%), but their sensitivities varied. Thus, the results of bioassays and assays with DNA probes normally used to search for adherent E. coli did not correlate well, and the best method for the identification of these organisms in the clinical research setting remains controversial. Isolates presenting diffuse adherence or hybridizing with the related daaC probe, or both, were by far the most frequent in patients (31.5, 26.0, and 23.0%, respectively), followed by isolates presenting aggregative adherence or hybridizing with the related EAEC probe, or both (21.5, 13.0, and 10.5%, respectively). None of the different combinations of adherence patterns and adherence-related DNA sequences found were associated with acute diarrhea.

Inhibition of enteropathogenic Escherichia coli adhesion to HeLa cells by serum of infants with diarrhea and by cord serum.

We have studied the effect of serum from infants with diarrhea and of cord serum on the localized adherence of enteropathogenic Escherichia coli (EPEC) to HeLa cells. Serum samples from 16 infants with diarrhea due to EPEC of serotypes O55:H6, O111: H-, O111:H2, O119:H6 and O142:H6 were used. The adherence ability of EPEC strains belonging to serotypes identical to (homologous) or different from (heterologous) those isolated from the infants' feces was highly inhibited by samples of infant serum collected both during the acute phase of the illness and upon discharge from the hospital. These data confirm the development of antibodies against EPEC adhesins and the cross-reaction between different EPEC serotypes. Cord serum inhibited the localized adherence of EPEC strains at different levels according to the serotype of the strain studied. These results suggest that the placental transfer of adhesin-related antibodies does not protect the newborn against EPEC infections, since half of our patients were less than 30 days old.

Inhibition of enteropathogenic Escherichia coli adhesion to HeLa cells by serum of infants with diarrhea and by cord serum

We have studied the effect of serum from infants with diarrhea and of cord serum on the localized adherence of enteropathogenic Escherichia coli (EPEC) to HeLa cells. Serum samples from 16 infants with diarrhea due to EPEC of serotypes O55:H6, O111: H-, O111:H2, O119:H6 and O142:H6 were used. The adherence ability of EPEC strains belonging to serotypes identical to (homologous) or different from (heterologous) those isolated from the infants' feces was highly inhibited by samples of infant serum collected both during the acute phase of the illness and upon discharge from the hospital. These data confirm the development of antibodies against EPEC adhesins and the cross-reaction between different EPEC serotypes. Cord serum inhibited the localized adherence of EPEC strains at different levels according to the serotype of the strain studied. These results suggest that the placental transfer of adhesin-related antibodies does not protect the newborn against EPEC infections, since half of our patients were less than 30 days old

Immune response of Brazilian children to a Neisseria meningitidis serogroup B outer membrane protein vaccine: comparison with efficacy.

Since 1986, serogroup B Neisseria meningitidis has caused approximately 80% of the meningococcal disease in Brazil. In 1988, an epidemic caused by N. meningitidis B:4:P1.15 was recognized in the greater São Paulo area of Brazil. The São Paulo state government decided to vaccinate children from 3 to 83 months of age with a vaccine consisting of serotype 4 outer membrane protein and group C meningococcal polysaccharide that was produced in Cuba. About 2.7 million children were vaccinated during two immunization campaigns conducted in 1989 and 1990. Because of this, a case-control study was designed to determine vaccine efficacy against group B meningococcal disease. The purpose of our study was to compare the antibody response with the protection from disease estimated from the case-control study. We measured the immune responses of vaccinees by enzyme-linked immunosorbent assay (ELISA), immunoblot, and bactericidal assay. The development of bactericidal antibodies was age dependent and in good agreement with the results of the case-control study. Only 40% of vaccinees showed fourfold or greater increases in bactericidal antibody titers after vaccination. A poor correlation between antibody levels detected by ELISA and those by bactericidal assay was found. Immunoblot analysis showed that about 50% of the serum samples with bactericidal titers higher than 1:4 were reactive with class 1 outer membrane protein. We conclude that the bactericidal assay is a good, laboratory-based, functional assay for the study of vaccine immunogenicity and that an effective solution to group B meningococcal disease remains to be demonstrated.

Prevalence of colonization factor antigens (CFAs) and adherence to HeLa cells in enterotoxigenic Escherichia coli isolated from feces of children in São Paulo.

Fifty-eight enterotoxigenic Escherichia coli (ETEC) strains, isolated from children with and without diarrhea in São Paulo, were examined for the presence of colonization factor antigens (CFAs) and their ability to adhere to HeLa cells. Antisera to CFA/I, the coli surface (CS) antigens CS1CS3, CS2CS3, and CS2 of CFA/II, CFA/III, and CS5CS6 and CS6 of CFA/IV were used. CFAs were identified in 43% of the ETEC strains: 40% of the CFAs strains with CFAs harbored CFA/I, 24% carried CFA/II (CS1CS3), 24% carried CFA/IV (CS6), and 12% carried CFA/IV (CS5CS6). CFAs occurred mainly among ETEC strains producing only heat-stable (ST-I) enterotoxin and in strains also producing heat-labile toxin (LT-I). No ETEC strains tested expressed CFA/III. A marked change in serotypes of ST-I-producing strains was found in São Paulo between 1979 and 1990. Adherence to HeLa cells was detected in 14% of the ETEC strains. All of them had a diffuse adherence pattern and produced only ST-I, and 88% carried CS6 antigen.

[Bacterial meningitis in the neonatal period. Clinical evaluation and complications in 109 cases]. / Meningite bacteriana no período neonatal. Evolução clínica e complicações em 109 casos.

Bacterial meningitis has special clinical features in the newborn infant. Major complications and sequelae result from the infectious involvement of the CNS in the majority of these children. We studied 109 newborn infants with bacterial meningitis accompanied from January 1977 to April 1987. The mortality rate was 34.8%. Perinatal risk factors were not found. The majority (80.5%) were term newborn infants. The main signs at admission were convulsion (53.2%), bulging fontanel (37.6%) and apnea (20.2%), and the main symptoms were neurosensorial depression (64.2%), nursing refuse (64.2%), fever (50.5%) and irritability (35.8%). Complications during hospitalization were ventriculitis (34.9%), inappropriate antidiuretic hormone secretion syndrome (27.5%), subdural collection (8.3%), brain abscess (4.6%) and brain infarction (2.8%). Inappropriate antidiuretic hormone secretion syndrome and ventriculitis were closely associated with high mortality. Seventy one children survived: 44 (62%) had gross abnormalities at the neurologic examination, and 29 (40.8%) developed hydrocephalus. Neurological follow-up of these children is important. Prognostic can change along the course of long time follow-up.

[Neonatal bacterial meningitis: etiological agents in 109 cases during a 10 year period]. / Meningite bacteriana neonatal. Agentes etiológicos em 109 casos durante período de dez anos.

The etiology of purulent meningitis was investigated in 109 newborn infants admitted in a neonatal intensive care unit throughout a ten year period. Bacterial pathogens were isolated from the CSF in 57 (52.2%) neonates. There was a predominance of Gram-negative bacilli isolated in 38 (34.9%) neonates. Gram-positive cocci were isolated from CSF in only 12 (11.0%) neonates. Microorganisms associated with nosocomial septicemia and meningitis in neonates--Klebsiella sp, Salmonella sp. Enterobacter sp, Pseudomonas sp, Flavobacterium meningosepticum and Serratia marcescens--were responsible for presumptive etiology in 38 (49.3%) among 77 patients with positive cultures in "closed sites". They were isolated from 22 (57.0%) neonates with prior hospitalization but only from 12 (34.3%) neonates coming directly from their households (chi 2 = 4.08; p < 0.05). The mortality rate was significantly higher in patients with positive CSF cultures (47.4%) in comparison to patients with negative cultures (18.4%) (X2 = 5.01; p < 0.05). It is possible to conclude that Gram-negative bacilli, many of them of hospital origin, are the major pathogens in this study. An improvement on neonatal health care and a scrupulous control of neonatal nosocomial infections are recommended.

Ongoing group B Neisseria meningitidis epidemic in São Paulo, Brazil, due to increased prevalence of a single clone of the ET-5 complex.

Beginning in 1988, the incidence of meningococcal disease in the area of greater São Paulo began to surpass the upper confidence limit of an 8-year average incidence (from 1979 to 1986), thus characterizing a new epidemic in the region of greater São Paulo. This epidemic, which extended to 1990, was different from previous epidemics in that it was caused by serogroup B. The increased incidence of meningococcal disease was paralleled by an increased prevalence of a single group B clone, B:4:P1.15, of the ET-5 complex. ET-5 strains have been present in the greater São Paulo area since 1979; however, they have been associated with a high percentage of the group B disease only from 1987 to the present. On the basis of the increased incidence of group B disease in São Paulo, a mass vaccination program with a serotype 4:P1.15 meningococcal protein vaccine was undertaken. The impact of this vaccination program is under analysis.

Emergence of a new clone of serogroup C Neisseria meningitidis in São Paulo, Brazil.

Serogroup C isolates of Neisseria meningitidis recovered from 121 patients with meningitis or septicemia in Greater São Paulo, Brazil, between 1976 and 1990 were analyzed with respect to serotype and multilocus enzyme genotype. The distribution of serotypes has changed since 1989 when serotype 2b started to replace serotype 2a. There were 48 distinct multilocus genotypes (electrophoretic types [ETs]) and 13 distinct complexes. Among the 41 serotype C:2b:- strains analyzed, 38 (93%) were found in complex 11. The percentage of complex 11 increased from 8% in 1988 to 50 and 66% in 1989 and 1990, respectively. Although we have been in an epidemic situation due to serogroup B:4:P1.15 ET-5 complex since 1988, the appearance and increase of a new unrelated strain, C:2b:- of ET-11 complex, in 1989 and 1990 provide enough data to conclude that the presence of two different complexes, ET-5 and -11, of N. meningitidis were responsible for the high levels of meningococcal disease in Greater São Paulo during this period.

Use of plasmid profiles to differentiate strains within specific serotypes of classical enteropathogenic Escherichia coli.

1. The usefulness of plasmid profile analysis to differentiate strains of enteropathogenic Escherichia coli (EPEC) was evaluated by studying 123 strains of the most prevalent serotypes causing infant diarrhea in the city of São Paulo, Brazil, i.e., O111ab:H-, O111ab:H2 and O119:H6. 2. No common profiles were found among strains of distinct serotypes. However, within each serotype, most of the strains were grouped within a few major profiles. More than 68% of the strains of serotypes O111ab:H- and O111ab:H2 were included in 6 and 9 major profiles, respectively. In serotype O119:H6, about 48% of the strains were included in 3 major profiles. 3. This analysis suggests that only a few EPEC clones are causing infant diarrhea in São Paulo and revealed that the distribution of serotypes O111ab:H- and O111ab:H2 during the one-year study was at least partly determined by small outbreaks of the most common profiles. 4. We conclude that plasmid profile analysis is very useful to differentiate strains within specific EPEC serotypes.

Use of plasmid profiles to differentiate strains withi9n specific serotypes of classical enteropathogenic Escherichia coli

The usefulness of plasmid profile analysis to differentiate strains of enteropathogenic Escherichia coli (EPEC) was evaluated by studying 123 strains of the most prevalent serotypes causing infant diarrhea in the city of Säo Paulo, Brazil, i. e.,0111ab:H-, 0111ab:H2 and 0119:H6. No common profiles were found among strains of distinct serotypes. However, within each serotype, most of the strains were grouped within a few major profiles. More than 68% of the strainsof serotypes 0111ab:H- and 0111ab:H2 were included in 6 and 9 major profiles, respectively. In 0119:H6, abouth 48% of the strainswere included in 3 major profiles. This analysis suggewsts that only a few EPEC clones are causing infant diarrhea in Säo Paulo and revealed that the distribution of serotypes 0111 ab:H- and 0111ab:H2 during the one-year study was at least partly determined by small outbreaks of the most common profiles. We conclude that plasmid profile analysis is very useful to differentiate strasins within specific EPEC serotypes

Enteropathogens associated with acute diarrheal disease in urban infants in São Paulo, Brazil.

To determine the prevalence and epidemiology of enteropathogens in acute infantile diarrhea, 500 infants less than or equal to 12 months of age with diarrhea and 500 age-matched control subjects coming to a São Paulo emergency room were studied. Enteropathogens were identified in 55% of case infants and 10% of controls; enteropathogenic Escherichia coli (EPEC) of classic EPEC serotypes producing EPEC adherence factor (EAF) (26% of case infants), rotavirus (14%), Salmonella species (8%), enterotoxigenic E. coli (7%), and Shigella species (5%) were associated with diarrhea. Isolation of EAF+ classic EPEC decreased with increasing age of cases and peaked in spring, whereas rotavirus was least common in early infancy and peaked in fall and winter. Bloody stool had a 36% positive predictive value for Shigella infection, EAF+ classic EPEC were highly resistant to antimicrobial drugs. Among poor São Paulo infants, EAF+ classic EPEC equaled or exceeded rotavirus throughout the year as a cause of diarrhea bringing children to medical attention.

Percutaneous-endoscopic biliary stent placement. A preliminary report.

The placement of large-bore endoprostheses for relief of biliary obstruction by the percutaneous-transhepatic route is painful, requires a large hepatic parenchymal tract, and has a fairly high complication rate. The alternative technique of endoscopically placing similar-sized stents requires special instruments and skills, and may fail in passing very tight stenoses. We report a simpler combined percutaneous-endoscopic biliary stent (PEBS) placement technique with a high placement rate used in 11 patients with advanced malignant obstruction. In all 11 patients, 10 and 11.5 French stents were easily placed. Three patients developed sepsis but responded to antibiotics. One clogged stent required replacement. Two stents needed later endoscopic adjustment. Results of liver function test improved in 10 patients, and 8 patients showed improved quality of life.