Body weight gain and hippocampal volumes of rats exposed neonatally to psychostimulants

There is increasing evidence that early exposure to psychostimulants exerts long-lasting effects on the central nervous system. Yet, analysis of the body weight gain and volumetric determinations of brain areas have not been performed by comparing the effects of neonatal exposure to cocaine and amphetamine. Male (Wistar) rats were given cocaine hydrochloride (15 mg/kg body weight/day), D-amphetamine sulphate (25 mg/kg body weight/day) or saline, s.c., twice daily, from postnatal day (PND) 1 to 30. The experimental design used random permuted blocks of 4 males per litter -9 litters for body weight gain evolution and 9 for the analysis of body, brain and cerebellum at PND30. Volumes of the hippocampal formation were calculated in horizontal serial sections of celloidin embedded material from 6 animals per group. The analysis of body weight gain evolution was performed using discriminant functions and allowed the separation of the amphetamine group from the remainder and the control from the psychostimulants group; weight gain in PND 24-30 period presented the highest discriminating power. The mean volume of the hippocampal formation was lower in the psychostimulants group, and the differences were significant in the molecular layer of the dentate gyrus of cocaine and amphetamine exposed animals when compared with the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostic significance of aromatase and estrone sulfatase enzymes in human breast cancer

The aromatase and estrone sulfatase enzymes are important sources of local synthesis of biologically active estrogens in human breast cancer. Significant intratumoral aromatase activity was detected in 91/145 (63%) of tumors and estrone sulfatase was detected in 93/104 (89%) of tumors. There was no relationship between aromatase activity and tumor size, site, nodal status, menopausal status or estrogen receptor status. There was a significant correlation between the aromatase activity and histological grade, with an excess of aromatase-positive in the high grade tumors (P = 0.03). There was a marginally inverse correlation between the aromatase activity and time to relapse (P < 0.1), a significant correlation between aromatase activity and survival after relapse (P < 0.05) but not with overall survival (P > 0.1). Intratumoral estrone sulfatase activity was not significantly correlated to any putative prognostic factors, nor with time to relapse nor overall survival time.

Changes in the retinal ganglion cell layer and optic nerve of rats exposed neonatally to cocaine

The effects of neonatal exposure to cocaine upon the structure of the visual system are poorly understood despite the evidence of eye abnormalities in infants exposed in utero to cocaine. We previously demonstrated alterations in the optic nerve of rats exposed neonatally to cocaine, although no changes were detected in the number of its axons. This study was undertaken to investigate the retinal ganglion cell layer and the size distribution of the optic axons, in an attempt to assess further changes in the visual pathways. Groups of rats (Wistar strain) were given subcutaneous injections of cocaine hydrochloride (15 mg kg-1 body weight day-1) divided into two daily doses, from the day following birth until postnatal day 30 Controls were given subcutaneous saline throughout the same experimental period. Per group, five animals from three different litters were evaluated morphometrically. Following perfusion with aldehydes, samples from the median ventral and dorsal parts of the retina and the optic nerves were processed for electron microscopy. Morphometric techniques at light and electron microscopic levels allowed us to determine the following. (a) In the optic nerve: (1) frequency size-distribution of myelinated nerve fibres; and (2) number of myelin sheaths per fibre. (b) In the retina: (1) thickness of the layers; (2) frequency size-distribution of ganglion layer neurons; (3) mean cell nuclear size; and (4) packing density of ganglion cell layer neurons.(ABSTRACT TRUNCATED AT 250 WORDS)

Testing of nursing theory: critique and philosophical expansion

The authors first critique Silva's 1986 article in Advances in Nursing Science entitled "Research Testing Nursing Theory: State of the Art." They specifically focus on her evaluation criteria for the empirical testing of nursing theory and then develop evaluation criteria for three alternative approaches to theory testing in nursing. In addition, they describe how philosophy in general, and epistemology in particular, affect testing of nursing theory. Finally, they raise philosophical issues and state conclusions related to the testing of nursing theory within the discipline and practice of nursing.

Scientific fraud: definitions, policies, and implications for nursing research

Scientific research typically has been founded on high ethical standards established by researchers in academia and health care research institutions. Scientific fraud, an act of deception or misrepresentation of one's own work, violates these ethical standards. It can take the form of plagiarism, falsification of data, and irresponsible authorship. Scientific fraud has been attributed to misdirected attempts to attain high levels of personal and professional success. Researchers so prone commit scientific fraud in a search for promotion, status, tenure, and the obtaining of research grants. To divert scientific fraud, three recommendations are suggested: (1) socialize prospective nurse researchers into an atmosphere where intellectual and professional integrity prevail; (2) have established nurse researchers serve as role models and mentors who can educate the neophyte researcher about the ethics of research, including scientific fraud; and (3) emphasize and reward quality in research and publications, rather than quantity.

Delta-aminolevulinate dehydrase (ALAD) polymorphism in mixed Brazilians from the State of Bahia

Electrophoretic polymorphism of delta-aminolevulinate dehydrase (ALAD) was studied on 519 individuals from Bahia, Brazil. Subjective assessment of Black ancestries carried out in a five point visual scale (White, Light Mulatto, Medium Mulatto, Dark Mulatto and Black) allowed to show that the ALAD*2 allele frequency decreases from 8% in Whites to 0% in Blacks. These findings agree with previous reports of ALAD in Africans, American Indians and Spanish. The powerful peculiarity of the ALAD system in assessing racial admixture is stressed.

Null allele in a human polymorphism restricted to the placenta: call for a search

The identification of a null allele in a human genetic system restricted to the placenta is a great challenge for two reasons: the impossibility of carrying out family studies and the unviability of sample recollections because the placenta itself is a disposable universe. Thus, in addition to reporting the finding of a null phenotype of placental alkaline phosphatase in a dark mulatto newborn from a black mixed population of Bahia, Brazil, here we present other evidence for the presence of the ALPP*Q0 allele with considerably high frequency in this population.

[Autoimmune phenomena in the elderly]

We analyzed sera from 102 subjects older than 65 years of age with no clinical evidence of autoimmune disorders, inflammatory diseases or pharmacological interventions. Positive titers for antinuclear antibodies were found in 18.6%, anti-smooth muscle fibre in 16.6%, and rheumatoid factor in 11.8%. These values were significantly higher than those of a control group of healthy younger adults (p < 0.0001). Anti mitochondrial antibodies were present in 1% (NS). Thus, a greater proportion of autoimmune phenomena is demonstrated in the elderly.

Anorectal electromanometry in the diagnosis of neuronal intestinal dysplasia in childhood

The diagnosis of neuronal intestinal dysplasia (NID) is currently established by histochemical procedures. From October 1, 1981, until July 31, 1990, we submitted a total number of 737 patients under 15 years of age with several distinct colonic and anorectal disorders, to clinical, radiological, electromanometrical, histochemical and histological evaluation. 573 had a clinical diagnosis of chronic constipation, and in 38 of these NID could be demonstrated by histochemical examination. Motivated by our own findings with the anorectal electromanometry in these patients we performed a double-blind prospective study to find out if there are any particular and pathognomonic manometric parameters of NID in childhood. 80% of our patients with NID diagnosed prospectively since April 1st, 1986, had a relaxation of the internal anal sphincter which was not proportional to the volume of rectal distention. Anorectal hyperexcitability was also present in these patients, whereas a statistically highly significant (p less than 0.01) increase of the amplitude of anorectal fluctuations (7.27 +/- 1.12 mmHg) as compared to the values measured in our own patients with functional chronic constipation (2.87 +/- 0.33 mmHg) could be demonstrated. Considering only those patients who simultaneously presented all of the above mentioned electromanometric criteria (e.g. non-proportional relaxation of the internal anal sphincter, anorectal hyperexcitability, increased amplitude of anorectal fluctuations) without an increase of the anorectal pressure profile, we could demonstrate that the correlation between the electromanometric diagnosis of NID and the final histochemical diagnosis was 100%. Nevertheless, under these conditions, 30% (9 out of 30) of patients with NID were not recognized electromanometrically because they had been excluded as false negative cases.(ABSTRACT TRUNCATED AT 250 WORDS)

[A preliminary study of the factors which lead to patient readmission in psychiatric hospitals]

The readmission of patients to psychiatric hospitals is preoccupying. This occurrence led us to this study which has as objective the identification of the determinant factors of the readmission; the nurse's opinion of what can be done to attenuate and the source of knowledge on the topic. The date collection was carried out with twenty three nurses of three countries: Peru (7), Brazil (9) and Colombia (7). The following factors were evidenced: social-economical, lack of orientation of family members and patient and institutional policy. Activities mentioned were actions directed toward working with families and patients, team work and community work. The sources of information most frequently mentioned were daily practice, reading and events. Some differences were evidenced among the three countries.

Intratumoral aromatase as a prognostic factor in human breast carcinoma

Intratumoral aromatase activity (AA) was measured in 145 samples of human primary breast carcinoma using the tritiated water release assay which quantifies the tritium lost to water during the aromatization of 1 beta-[3H]androstenedione to estrone. Significant AA was detected in 91/145 (63%) tumors. The possibility of a relationship between AA and a variety of clinical prognostic factors such as estrogen receptors, menopausal status, site, size, and histological grade of tumor was investigated. Possible relationship with time to relapse, overall survival, and survival of patients after relapse were also studied to determine whether intratumoral AA itself was of any prognostic value. There was no relationship between AA and tumor size, site, nodal status, menopausal status or estrogen receptors. However there was a significant correlation between AA and histological grade with an excess of AA-positive tumors having high grade (P = 0.03). There was no significant relationship between AA and overall survival (P greater than 0.1), but there was a marginal inverse correlation between AA and time to relapse (P less than 0.1). A statistically significant correlation was found between AA and survival of patients after relapse (P less than 0.05).

Follow-up of the antibody response to measles vaccine in a rural area of Guinea-Bissau

One hundred and fourty-four children who either were already immune or had been successfully immunized against measles were reexamined after 16 months. All still had circulating Elisa antibodies at a clearly detectable level. Titres were higher in the group of children stated to have had measles prior to the immunization. None of the children had measles after immunization. Boostering by the wild virus may have occurred, whereas no evidence of a booster effect from the vaccine was found. About one third of the children were underweight. Plasmodium falciparum parasitaemia rate, and also its seasonality, varied with the location of the child's homestead. Even children exposed to mesoendemic P. falciparum malaria and moderate malnutrition can be successfully immunized with a conventional live attenuated measles vaccine from 8 months of age, which probably results in a lasting protection.

Controlled trial of enalapril and hydrochlorothiazide in 200 hypertensive patients

In a multicenter, multinational study, 200 patients with essential hypertension were treated with a fixed dose of Enalapril (E) 20 mg/day after a 2- to 4-week placebo period. All had diastolic blood pressure (DBP) 100 to 120 mm Hg at the end of the placebo period. They were then given E for 6 weeks. If DBP after this was greater than 90 mm Hg they were randomized double-blind to added therapy with hydrochlorothiazide (H) either 25 mg/day (E + H 25) or 12.5 mg/day (E + H 12.5) or placebo (E + P) for 4 weeks. Blood pressure was measured approximately 24 hours after taking the medication. In the whole group, BP fell from 171/107 to 156/97 mm Hg during monotherapy with E (P less than 0.001). Sixty-six patients reached DBP less than or equal to 90 mm Hg on E alone. Of the remainder, 42 were randomized to E + P. In these, BP fell by 5.9/3.4 mm Hg (P less than 0.05). Forty-two patients received E + H 12.5 and BP fell by 9.0/6.9 mm Hg (P less than 0.001). Forty-one patients received E + H 25 and BP fell by 5.6/6.3 mm Hg (P less than 0.05/0.01). The proportion of patients who reached DBP less than or equal to 90 mm Hg was 26% in the E + P group, 48% in the E + H 12.5 group (P less than 0.05 compared to E + P group), and 38% in the E + H 25 group. There were no other significant differences between the E + H 12.5 and E + H 25 groups except that S-potassium fell significantly (-0.2 mmol/L) in E + H 25. Both regimens were remarkably well tolerated. It can be concluded that H 12.5 mg/day potentiates the effect of Enalapril 25 mg/day at least as well as H 25 mg/day and better than placebo.

Research testing nursing theory: state of the art

The degree to which investigators have tested nursing theory through empirical research is analyzed. The analysis is based on 62 studies in which the nursing model of Johnson, Roy, Orem, Rogers, and/or Newman was used as a framework for the research. The analysis shows that of these 62 studies, only nine met specified evaluation criteria for the explicit testing of nursing theory. To better understand this finding, impediments and approaches to testing of nursing theory are discussed, as well as implications for nursing theory, research, and practice.

Augmented antibody response to live attenuated measles vaccine in children with Plasmodium falciparum parasitaemia

The impact of malarial infection on the humoral immunological response to measles virus antigen was studied in 184 children aged 8-19 months in Guinea-Bissau. Pre- and post-immunization measles serology was performed using dried blood on absorbent paper and the ELISA technique. Blood smears obtained at the time of vaccination and 2 and 4 weeks afterwards were examined for malaria parasites. Pre-vaccination antibodies to measles were found in 44 out of 184 children (24%). Plasmodium falciparum was identified in 62 of the 132 initially non-immune children who completed the study. The rate of seroconversion was 127 out of 132 (96%). Post-immunization measles antibody titres were significantly higher in the vaccinees with P. falciparum than in those without malaria parasites in the blood.

Comprehension of information for informed consent by spouses of surgical patients

The adequacy of comprehension of the information needed for informed consent to participate in research on spouse responses to a husband's or wife's general surgery was assessed. Comprehension of information about the research study by 75 spouses was measured by the Informed Consent Questionnaire containing questions on study purpose, time involvement, nature of participation, risks, benefits, voluntariness, confidentiality, and anonymity. The result showed that 72 of the 75 spouses had adequate comprehension of the information for informed consent. Because adequate comprehension is atypical of most studies, possible reasons for this unexpected result are discussed and then explained within a self-determination theory of informed consent.

Persistence of DNA lesions and the cytological cancellation of sister chromatid exchanges

The ability of UV light, mitomycin C and ionizing radiation to induce the formation of sister chromatid exchanges (SCEs) at the same locus in successive cell generations was investigated in human lymphocytes. Cells were exposed to the DNA damaging agents after they had completed their first round of DNA replication, and SCEs were examined at the third division in chromosomes that had been differentially stained three ways. Although some of these treatments induced long-lived lesions that increased the frequency of SCEs in successive cell generations, none of the lesions led to the formation of consecutive SCEs at the same locus in successive cell generations. This observation seriously challenges the hypothesis that SCE cancellation results as a consequence of persistence of the lesions induced by these agents.