Skin cancers and precancerous lesions in Parkinson's disease patients.

Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies.     

Serum lipids levels and some risk factors of cardiovascular diseases in a population of the municipality of S?o Paulo, SP (Brazil)

An attempt was made to characterize lipemic levels according to sex, age and presence or absence of cardiovascular disease risk factors, in a population of 3,792 people between the ages of 20 and 59, in terms of smoking habits, obesity, family history of diabetes and use of oral contraceptives. Those individuals who did not present any of the risk factors mentioned were classified as "exempt". After submitting the data to variance analysis it was found that: for men between 20 and 49 years of age there were high significant differences in the averages obtained for the seric levels of total lipids, triglycerides and total cholesterol between "exempt" and obese and "exempt" and obese with a family history of diabetes; for the 50 to 59 age group there were significant differences in the average of the values corresponding to the seric levels of total lipids between "exempt" and those individuals in whom obesity appeared associated with smoking habits or associated with a family history of diabetes. The averages obtained for seric triglycerides were significantly different between "exempt" and non-obese with a family history of diabetes, obese, obese smokers and obese with a family history of diabetes. On the other hand, the averages relating to seric levels of total cholesterol were different, at significant levels, between "exempt" and obese smokers; the risk represented by the smoking habit showed no relevance with regard to the lipemic levels in any group except for that of men between 30 and 39 years of age. In their case, there were significant differences between the averages obtained for the seric levels of total lipids, triglycerides and total cholesterol, between "exempt" and smokers and between "exempt" and obese smokers. It is to be noted that the differences obtained with regard to the averages relating to lipemic levels as between "exempt" and obese were less those obtained between "exempt" and obese smokers, thus showing the possible relevance of the risk presented by the smoking habit; -- among the women there were less accentuated differences in the averages corresponding to the lipemic levels as between "exempt" and those who presented one or more risk factors. Thus, for the age group from 20 to 29 there were significant differences in the averages obtained for total lipids as between "exempt" and obese.(ABSTRACT TRUNCATED AT 400 WORDS)     

Atropine and hexamethonium-sensitive,Ca/K-modulated,reversible swelling of mast cells in rat mesentery,due to feeding or exposure to carbachol

Transitory swelling of mesenteric mast cells was observed when 24 h-fasted rats were given access to food. Atropine, an anti-muscarinic drug given (1 mg/kg, i.p.) 60 min prior to feeding, prevented this response; carbachol, a cholinomimetic drug caused it to occur when given (2 g/kg, i.v., 10 min) to fasted rats. Mast cells in the mesentery excised from fasted rats, presented swellingin vitro within 1 min following exposure to 10^–7 M carbachol. This response was inhibited by atropine (10^–8 M) or hexamethonium (10^–8 M), indicating that stimulation of a parasympathetic nerve pathway, reported to exist in rat mesentery, could induce mast cell swelling. Exposure to a Ca²⁺ free medium also led to rapid swelling of mast cells in the mesentery excised from fasted rats. This result, as well as inhibition of the mast cell response to carbachol caused by increasing the Ca²⁺ (but not by increasing the Mg²⁺) content of the incubation medium, suggests that swelling was caused by a sudden decrease of Ca at mast cell membrane sites controlling ion/water fluxes. Mast cells swollen by feeding, carbachol, or Calack, reverted to their original condition within 20 min when incubated in balanced salt buffer. Such reversal did not occur in a KCl-enriched medium. An equivalent (in terms of ionic, strength), increase in NaCl, did not reproduce this effect, indicating that mast cells have K⁺-dependent means of compensating for endogenously or drug-induced volume changes. Swelling caused by cholinergic stimulation of mast cells was not accompanied by granule exocytosis. The, implication of these findings, as well as of the kininogen decrease previously reported to occur in carbachol-treated rat bloodin vivo orin vitro, is discussed in terms of putative mast cell-controlled, localized homeostasis in the rat mesentery.     

Chain conformation and compatibility in polymer blends. A small-angle X-ray scattering study of the system poly(propylene glycol)-poly(methyl methacrylate)

The thermodynamic compatibility of dilute, solid solutions of poly(propylene glycol) (PPG) (mass-average molar mass M?_w = 3900 g/mol) in poly(methyl methacrylate) (PMMA) (M?_w = 550000 g/mol) was investigated by means of small-angle X-ray scattering. The results of the analysis show that PPG is molecularly dispersed in the solid, amorphous matrix of PMMA, and that the molecules display the typical statistical coil macroconformation of polymers in dilute, liquid solution, whereby the numerical value of the second virial coefficient seems to point to the unperturbed nature of the coils. This behaviour, consistent with the concept of “interpenetration of segments”, is in total agreement with the experimentally measured compositional variation of the glass transition temperature of the blends.     

Production of type II heat-labile enterotoxin by Escherichia coli isolated from food and human feces.

Escherichia coli strains isolated in Sao Paulo, Brazil, from feces of patients with diarrhea and from food samples produced toxin(s) that was shown to be related both immunologically and genetically to the recently characterized type II heat-labile enterotoxin of E. coli. The new isolates of type II heat-labile enterotoxin-producing E. coli belonged to five different serotypes and did not represent a single clone.     

Hepatitis B virus transmission in Brazilian hemodialysis units: serological and molecular follow-up

A serological and molecular study of hepatitis B virus (HBV) infection was carried out in dialysis units in Central Brazil. Between 1995 and 1999, serum samples from all HBsAg-positive hemodialysis patients (n = 43) were tested for HBeAg/anti-HBe and subtyping by monoclonal ELISA. HBV DNA was detected by PCR and positive samples were genotyped by restriction fragment polymorphism pattern (RFLP) methodology. TheHBsAg prevalence declined in this population during the survey period (12-5.8%). HBeAg and anti-HBe were detected in 23 (53.5%) and 18 (41.9%) sera, respectively. Thirty-six samples could be HBsAg subtyped: 21 were subtype ayw(3), 14 belonged to adw(2) and one was identified as adw(4). HBV DNA was present in 30 serum samples. Of these, 20 (66.7%) were genotype D, 9 (30%) genotype A, and 1 (3.3%) genotype F. In addition, the RFLP pattern could be determined in samples from 18/20 genotype D patients: D3 (10 strains), D7 (7 strains) and D4 (1 strain); from 8/9 genotype A patients: A1 (6 strains) and A3 (2 strains); and from the patient infected with genotype F: F1. Patterns D3 and D7 were associated closely with HBV infection in the two largest hemodialysis units studied. These findings confirm the value of the RFLP method as an effective molecular epidemiological tool for elucidating HBV transmission in hemodialysis units.     

Heterogeneity of the polyribocytidilic acid tract in aphthovirus: changes in the size of the poly(C) of viruses recovered from persistently infected cattle

A sample of aphthovirus type C3 strain Resende carrying two polyribocytidilic acid [poly(C)] tracts was cloned in tissue culture. One clone with a poly(C)-rich tract of about 145 nucleotides long (clone 3B) and another with a poly(C)-rich tract of about 230 nucleotides long (clone 12) and a mixture of both were injected intralingually into three steers. Samples from all three animals were recovered during the acute phase of the disease, from the blood and from the feet, and at various days after inoculation from the oesophageal-pharyngeal (OP) fluids. Analysis of the viral RNAs of the positive samples by means of RNase T1 maps on one- and two-dimensional gels showed (1) changes in the electrophoretic mobility of the poly(C)-rich tracts of viruses recovered from the OP fluids at various times after infection; (2) selection of virus populations with poly(C)-rich tracts of increased size; (3) later on, changes in the patterns of oligonucleotides of persistent viruses. These variations may lead to the production of new strains with altered biological properties that may contribute to the maintenance and spread of these viruses in the field.     

Potentiation of FMD vaccines with polycationic-nucleic acid complexes

Summary The effect of various polycations on the immune response potentiated with poly I:C was studied. It was found that low molecular weight polycations had no potentiating effect. Polylysine was ineffective whereas protamine was superior to lysozyme, poly-arginine, poly-histidine, DEAE-Dextran and histone.A foot-and-mouth disease trivalent vaccine composed of strains A₂₄ Cruzeiro, O₁ Caseros and C₂ Resende elicited no immune response in swine when adjuvanted with aluminium hydroxide but was effective when emulsified in oil. In general, the immune response was potentiated ten-fold when the emulsion contained poly I:C. The antibody production was in most cases further potentiated by a factor of ten when the nucleic acid double-strand was complexed with 1:10 (w/w) DEAE-Dextran. Protamine was as effective, or perhaps even more, than DEAE-Dextran to this effect.Guinea pigs vaccinated with a water-in-oil emulsion type monovalent C₃ vaccine showed an increase in antibody production when the vaccine contained poly I:C or poly I:C complexed with 1:10 (w/w) protamine.With 4 Figures