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Phenotypic plasticity is an important means by which plants cope with environmental heterogeneity; therefore, understanding variation in plant traits in heterogeneous habitats is important to predict responses to changing environments. In this study, we examined the patterns of intraspecific variation in leaf traits of Miconia albicans (Melastomataceae), a widespread, obligatory apomictic shrub, across a soil fertility gradient in the Cerrado (Brazilian savanna). We predicted high plasticity because selection favours high phenotypic plasticity in asexual populations with low genetic variability. Leaves were sampled in campo sujo (grassland), cerrado (savanna) and cerradão (woodland) in south-eastern Brazil during both dry and rainy seasons to calculate leaf area, specific leaf area, leaf tissue thickness, trichome and stomata density. We found significant between-season variation in leaf traits, indicating that the production of season-specific leaves is a strategy to cope with the strong seasonality. Both multivariate analysis and the relative distance plasticity index indicate lower plasticity during the dry season, especially under shade. Our results show that the phenotypic plasticity can be modulated by changes in abiotic factors and the combination of shade and drought can limit the expression of phenotypic plasticity.

The efficacy and tolerability of azithromycin and erythromycin in the treatment of acute respiratory tract infections in children were compared in an open, multicenter, randomized trial. A total of 151 children, aged from 2 months to 14 years, suffering from upper airways infections (60), or lower respiratory tract infections (91), were randomized to be treated either with azithromycin, 10 mg/Kg/day per os once daily for 3 or 10 mg/Kg/day 1 and 5 mg/Kg/days 2-5 (77 patients) or with erythromycin, 50 mg/Kg/day thrice daily for at least 7 days (74 patients). The two treatment groups did not significantly differ as to sex, age, weight, type and severity of infection, and infecting pathogens. Clinical evaluation was performed prior to therapy, on treatment days 1, 3, 5 and 7, and on day 10. Microbiological and laboratory assessment were carried out at baseline and after the end of therapeutic course. Chest X-ray and serologic assays for Mycoplasma pneumoniae infection were obtained in patients suspected to have lower respiratory tract infections. At the end of therapy, clinical cure was achieved in 73 out of 77 patients (94.8%) in the azithromycin group, and in 60/72 evaluable subjects (83.3%) in the erythromycin group. A significantly more rapid remission of several illness-related signs and symptoms was observed in patients treated with azithromycin. A total of 75 bacterial pathogens were isolated at baseline microbiological examination; at the end of the therapeutic course bacteriological eradication was obtained in 34/34 cases (100%) treated with azithromycin, and in 40/41 children (97.5%) treated with erythromycin.(ABSTRACT TRUNCATED AT 250 WORDS)

The incidence of nosocomial infections (NI) and the related risk factors in a Department of Pediatric Cardiovascular Surgery were studied, during a 6 months period. 155 successive admissions were considered. Nosocomial infections were 17 (11%), nosocomial colonizations 18 (11.6%). The most important risk factors for nosocomial infections were: age, cyanosis, duration of hospitalization, hospitalization in Intensive Care Unit and central venous catheter only as a risk factor for sepsis. The most important risk factors for nosocomial colonizations were: tracheal intubation and central venous catheter. In 4 cases the NI was related to nosocomial colonization (2 sepsis, 1 pneumonia, 1 wound infection). The most frequently isolated microorganisms were Pseudomonas aeruginosa and Staphylococcus spp. The Authors found that a longer than 5 days period of antibiotic prophylaxis did not reduce the incidence of nosocomial infections.

Kawasaki disease (KD) is a new, well characterized pediatric syndrome. In this work the last epidemiologic, diagnostic and clinical data are pointed. Especially the heart-disease and its monitoring and therapy are studied. Our casuistry (5 cases in 4 years) is also presented. The international literature and our clinical experience suggest that KD is more spread than we think and therefore in needs to be studied carefully by the pediatricians.

Five children from one to seven years of age with intrahepatic ductular hypoplasia are presented. Clinical and biochemical characteristics of the disease are specifically considered as well as differential diagnosis. In three patients a severe hemolytic anemia, only partially corrected with vitamine E, was present. All subjects received continuous cholestyramine therapy. Variable follow up from nine months to seven years demonstrated persistent intrahepatic cholestasis with hypercholesterolemia in two cases, clinical and biochemical improvement in one case. One child died two years and six months after diagnosis was made an one patient was lost to follow up. The Authors confirm the literature clinic, diagnostic and therapeutic data concerning ductular hypoplasia, while, on the basis of their experience, the prognosis seems poor also in some cases of syndromic ductular hypoplasia.

The Authors studied the behaviour of ABsAb in a pediatric case-list made up of 8 cases of virus B acute hepatitis, and 63 cases of chronic hepatitis in different evolutive phases: besides, this investigation was extended to 48 healthy carriers (29 of whom bioptically confirmed) and 35 cases of cohabitants with HBsAg-positive hepatic chronic patients. In acute hepatitis the antibody pattern, even if delayed in time, mimics the modalities of the organic response against exogenous stimulations, therefore it constitutes an index of past disease and recovery. In chronic hepatitis (both HBsAg-positive and negative) the specific antibody to the surface antigen is present only at a low percentage (27%) and generally at low titres. In healthy carriers, bioptically ascertained, it is practically absent as to suggest more careful consideration when it turns out present (pseudo-carriers?), while in the cohabitants with virus B patients, especially if chronic, along with HBsAg detection, it consitutes an indispensable element for their classification in patients, ex-patients, not infected and healthy carriers. A very interesting finding, requiring further confirmation, is the unusual behaviour of these antibodies in some cases of relapsed chronic hepatitis.

This study was undertaken to determine, first the relationship between the Sabin-Feldman dye test and the enzyme-linked immunosorbent assay (ELISA) as far as the antitoxoplasmic IgG antibodies are concerned, and secondly the relationship between the indirect immunofluorescence test and the ELISA as regards the antitoxoplasmic IgM antibodies. The results achieved through this research show a good relationship between the dye test and IgG-ELISA, especially satisfactory with the low and medium values of the antibody titers. Furthermore, a very good agreement could be documented between IgM-ELISA and IgM-IFAT in the detection of IgM-specific antibodies in the early phases of toxoplasmic infection.

The Authors studied the amount of anti-measles and anti-rubella heteroantibodies during chronic hepatitis and the possible role of these antibodies in eliciting and maintaining the hypergammaglobulinemic picture, characteristic of this morbid condition. The results they obtained in an almost exclusively pediatric case-list (37 cases) show, whenever the contact with these viruses (measles and rubella) occurred, a percentage of subjects with comparatively higher levels among chronic liver patients in comparison with control patients, of the same age. The percentage of subjects with previous rubella infection and hemagglutination-inhibiting antibody levels higher than 1:256 is about 45% among chronic liver patients, compared with 13% in healthy subjects. As far as measles virus is concerned the percentage drops from 11% to 4%. The most reliable hypotheses to explain this interesting phenomenon, which, however, does explain only partially, and concerning some cases only, the entity of the hypergammaglobulineamia, are set forth briefly.

The results of immunosuppressive treatment (a corticosteroid-azathioprine combination) in 104 children suffering from chronic HBsAg-positive hepatitis are reviewed. A recovery and/or improvement of the majority of the cases treated was observed after two to seven years of therapy, in contradiction to the opinion of other authors who treated adult patients. A biochemical and/or bioptic deterioration was observed in some cases in which treatment was interrupted too soon; this was followed by an improvement when treatment was re-initiated. No serious side-effects were observed with the combination treatment.

The authors have performed a longitudinal study of 118 children affected with B virus chronic hepatitis. Our first observation revealed 92 children with HBeAg positive (26 CPH, 66 CAH), 22 children with anti HBe positive (6CPH, 15 CAH, 1 cirrhosis), 4 children (CAH) with e/anti-e negative. A correlation between the severity of clinical forms and the behaviour of the e/anti-e system was not observed. Seroconversion was observed during the follow up period in 37 of 92 subjects in an average time of 59.83 +/- 32 months, time rather prolonged in patients under immunosuppressive therapy. To compare the clinical progress and the evolution of CPH and CAH respectively, always with regard to the e/anti-e system, statistically significant differences did not result. Only anti HBe positive recovered subjects, inclusive of seroconverted patients and those anti HBe from the first observation, showed significant results to the statistical analysis. Still, seroconversion corresponds frequently to a stable improvement of hepatitis. On the contrary evolution into cirrhosis was observed in 5 patients that had anti HBe antibodies.

Plasma levels of isoniazid (INH) have been monitored in fifteen children, aged 1 to 13 years, who were under chronic therapy with INH plus rifampin for tuberculosis. The pharmacokinetic parameters of children were not significantly different from those found in adults by other authors. It is necessary to check two plasma concentrations at the 3rd h. versus different doses (5 mg/kg and 10 mg/kg) of INH, in order to determine the optimal dose to be given. In subjects with external ventricular drainage, the concentrations of INH in cerebro-spinal fluid are lower than in plasma. The latter finding should be stressed for its importance in the therapy of tuberculous meningitis.

A 12-month-old child neutropenic since the age of 8 months, was referred to our institute for a sepsis from Candida albicans. On exploring the cause of neutropenia, an anti-NA1 antibody could be detected in the patient's serum. This antibody seemed to be responsible for the neutropenia because the child's PMN type was NA1+. The reactivity of the autoantibody with the patient's own granulocytes was confirmed by direct and indirect immunofluorescence studies performed on blood and marrow cells. A reduced number of T lymphocytes with poor PHA responsivity has been interpreted as the possible cause of the autoimmune disease. Steroid therapy did not cure the neutropenia but the child's general condition improved.