Intravesical repair of vesicovaginal fistula guided by cystoscopy

Background

Vesicovaginal fistulas (VVF) are an unusual problem that may significantly affect a patient's quality of life. The main causes for this condition are labour complications (mostly in developing countries) and pelvic surgeries (in industrialised countries). Treatment may be conservative or surgical. Regarding surgical treatment, there is still debate about the best approach and surgical technique.

Objective

To demonstrate a correction of a VVF guided by cystoscopy using intravesical laparoscopic instruments.

Methods

Case report and surgical video of a recurrent VVF treated with a hybrid technique involving direct transvesical insertion of 3 mm laparoscopic trocars and instruments guided by cystoscopy. As far as we know, although there are some reported techniques that use a combination of transvesical laparoscopic instruments and cystoscopy, this is the least invasive and most ergonomic technique described.

Results

Two years after surgery, the patient remains asymptomatic and with no fistula recurrence.

Conclusion

The transvesical approach guided by cystoscopy seems to be an effective, safe and ergonomic minimally invasive procedure for VVF repair.

Residents' Perspectives on and Application of Dental Public Health Competencies Using Case-Based Methods

The aims of this study were to qualitatively assess dental public health (DPH) residents' perspectives on teaching methods for DPH competencies and to develop and implement a case-based simulation to address those competencies, constructed on the basis of the qualitative assessment. Focus group discussions were conducted with 18 DPH residents enrolled in two university-based DPH programs. Topic areas discussed in the two focus groups were perceived value of DPH competencies, ways to acquire new DPH skills/abilities, and additional skills/abilities needed by DPH residents. The focus groups' responses showed that the residents felt competent in the analytical thinking competencies such as research methodology and critiquing literature. They emphasized the importance of learning leadership skills and reported feeling somewhat uncertain about their mastery of the policy and advocacy and system evaluation competencies. Of the two distinct categories of DPH skills and competencies- analytical/critical thinking and practical competencies-these residents reported that a greater proportion of time needed to be devoted to integrating the practical competencies into their education. Based on the residents' feedback, the authors developed a structured seminar series taking a case-based approach to simulate real-world DPH problems, using real and semi-hypothetical planning projects to meet the residents' perceived needs and covering gaps between didactic learning and practice.

Functional profiles of coronal and dentin caries in children

Background: Dental caries results from a dysbiosis of tooth-associated biofilms and frequently extends through enamel into dentin which has a different structure and composition.

Objective: To evaluate the metatranscriptome of caries to determine the metabolic potential of caries communities compared with health.

Design: Samples from children, caries-free (CF: n = 4) or with coronal (CC: n = 5) or dentin (DC: n = 5) caries were examined for gene expression potential. Functional profiling was performed using HUMAnN2 (HMP Unified Metabolic Analysis Network).

Results: There was increased gene expression diversity in DC compared with CC and CF. Genes in CF included alcohol dehydrogenase from Neisseria sicca, methylenetetrahydrofolate reductase from Streptococcus sanguinis and choline kinase from streptococci. Genes in CC mapped mainly to Streptococcus mutans. Arginine deiminase in DC mapped to S. sanguinis and Actinomyces naeslundii. Glycerol kinase genes mapped to S. sanguinis in all groups whereas glycerol kinase in DC were from Rothia, Prevotella and streptococci. Uracil-DNA glycosylase in DC mapped to Prevotella denticola and Actinomyces. Repressor LexA in DC mapped to Scardovia wiggsiae, Dialister invisus and Veillonella parvula.

Conclusions: Functional profiling revealed enzyme activities in both caries and caries-free communities and clarified marked differences between coronal and dentin caries in bacterial composition and potential gene expression.

Morphological and Biochemical Assessment of the Cornea in a Gaucher Disease Carrier with Keratoconus

Ocular abnormalities such as corneal opacities and some specific alterations in ocular movements have been described in the neuropathic forms of Gaucher disease. This study was designed to correlate the clinical, morphological and biochemical findings in the corneal button obtained after keratoplasty in a Gaucher disease carrier with keratoconus. Morphologically, the cornea showed keratocytes with marked dilatations of the rough endoplasmic reticulum and intracytoplasmic "dark inclusions"; the acidic lipid profiles presented alterations in the cornea of the Gaucher disease carrier when compared with healthy controls and a clear deficiency in beta-glucosidase activity was detected as well. Our data suggest that the cornea may serve as a good marker of an early target organ in lipid metabolism disorders such as Gaucher's disease.

Long-term effects of chronic cocaine exposure throughout adolescence on anxiety and stress responsivity in a Wistar rat model

Adolescents display increased vulnerability to engage in drug experimentation. This is often considered a risk factor for later drug abuse. In this scenario, the permanent effects of cocaine exposure during adolescence on anxiety levels and stress responsivity, which may result in behavioral phenotypes prone to addiction, are now starting to be unveiled. Thus, the purpose of the present study was to evaluate the long-lasting effects of chronic cocaine administration during adolescence, on anxiety-like behavior and on stress response. Adolescent male Wistar rats were daily administered 45-mg cocaine/kg of body weight in three equal intraperitoneal doses with 1-h interval, from postnatal day (PND) 35 to 50. The effects of cocaine administration on anxiety levels, assessed in the Elevated Plus Maze (EPM), and on social stress response, assessed in the resident-intruder paradigm (R/I), were evaluated 10 days after withdrawal, when rats were reaching the adulthood. The underlying dopaminergic activity, and the corticosterone and testosterone levels were determined. Our results showed that cocaine induced long-lasting alterations in the hypothalamus-pituitary-adrenals (HPA) axis function and in testosterone levels. Such alterations resulted in significant and enduring changes in behavioral responses to environmental challenges, such as the EPM and R/I, including the evaluation of potential threats that may lead to high-risk behavior and low-benefit choices. This was further supported by an altered dopaminergic function in the amygdala and hippocampus. The present findings provide new insights into how the use of cocaine during adolescent development may modulate emotional behavior later in life. Compromised ability to recognize and deal with potential threats is an important risk factor to perpetuate compulsive drug seeking and relapse susceptibility.

Acetyl-L-carnitine provides effective in vivo neuroprotection over 3,4-methylenedioximethamphetamine-induced mitochondrial neurotoxicity in the adolescent rat brain

3,4-Methylenedioximethamphetamine (MDMA, ecstasy) is a worldwide abused stimulant drug, with persistent neurotoxic effects and high prevalence among adolescents. The massive release of 5-HT from pre-synaptic storage vesicles induced by MDMA followed by monoamine oxidase B (MAO-B) metabolism, significantly increases oxidative stress at the mitochondrial level. l-Carnitine and its ester, acetyl-l-carnitine (ALC), facilitate the transport of long chain free fatty acids across the mitochondrial membrane enhancing neuronal anti-oxidative defense. Here, we show the potential of ALC against the neurotoxic effects of MDMA exposure. Adolescent male Wistar rats were assigned to four groups: control saline solution, isovolumetric to the MDMA solution, administered i.p.; MDMA (4x10 mg/kg MDMA, i.p.); ALC/MDMA (100 mg/kg 30 min of ALC prior to MDMA, i.p.) and ALC (100 mg/kg, i.p.). Rats were killed 2 weeks after exposure and brains were analyzed for lipid peroxidation, carbonyl formation, mitochondrial DNA (mtDNA) deletion and altered expression of the DNA-encoded subunits of the mitochondrial complexes I (NADH dehydrogenase, NDII) and IV (cytochrome c oxidase, COXI) from the respiratory chain. Levels of 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) were also assessed. The present work is the first to successfully demonstrate that pretreatment with ALC exerts effective neuroprotection against the MDMA-induced neurotoxicity at the mitochondrial level, reducing carbonyl formation, decreasing mtDNA deletion, improving the expression of the respiratory chain components and preventing the decrease of 5-HT levels in several regions of the rat brain. These results indicate potential benefits of ALC application in the prevention and treatment of neurodegenerative disorders.

Prospective study of 5-year caries increment among children receiving comprehensive dental care in the New England children's amalgam trial

OBJECTIVE

To measure the 5-year caries increment among high-risk children during their participation in the New England Children's Amalgam Trial (NECAT), and to evaluate sociodemographic factors that may account for any observed disparities.

METHODS

NECAT recruited 534 children aged 6-10 with at least two decayed posterior occlusal surfaces from urban Boston and rural Maine. After restoration of baseline caries and application of sealants to sound surfaces, NECAT continued to provide free comprehensive semiannual dental care to participants. The net caries increment of children who completed the 5-year follow-up (n = 429) was calculated and predictors of caries increment were investigated using multivariate negative binomial models.

RESULTS

The majority of children (89%) experienced new caries by the end of the 5-year follow-up. Almost half (45%) had at least one newly decayed surface by the first annual visit. At year 5, the mean number of new decayed teeth was 4.5 +/- 3.6 (range 0-25) and surfaces was 6.9 +/- 6.5 (range 0-48). Time trends showed a noticeably higher increment rate among older children and young teenagers. Multivariate models showed that age (P < 0.001), number of baseline carious surfaces (P < 0.001), and toothbrushing frequency (<1/day versus >or=2/day, P = 0.04) were associated with caries increment. Only 48 children (11%) did not develop new caries.

CONCLUSIONS

Despite the receipt of comprehensive semiannual dental care, the vast majority of these high-risk children continued to develop new caries within 5 years. While disparities were observed by age, extent of prior decay, and toothbrushing frequency, no other sociodemographic factors were associated with caries increment, suggesting that the dental care provided during the trial reduced sociodemographic disparities in prior caries experience that were observed at baseline.

Rural and urban disparities in caries prevalence in children with unmet dental needs: the New England Children's Amalgam Trial

OBJECTIVES

To compare the prevalence of caries between rural and urban children with unmet dental health needs who participated in the New England Children's Amalgam Trial.

METHODS

Baseline tooth and surface caries were clinically assessed in children from rural Maine (n = 243) and urban Boston (n = 291), who were aged 6 to 10 years, with two or more posterior carious teeth and no previous amalgam restorations. Statistical analyses used negative binomial models for primary dentition caries and zero-inflated models for permanent dentition caries.

RESULTS

Urban children had a higher mean number of carious primary surfaces (8.5 versus 7.4) and teeth (4.5 versus 3.9) than rural children. The difference remained statistically significant after adjusting for sociodemographic factors and toothbrushing frequency. In permanent dentition, urban children were approximately three times as likely to have any carious surfaces or teeth. However, rural/urban dwelling was not statistically significant in the linear analysis of caries prevalence among children with any permanent dentition caries. Covariates that were statistically significant in all models were age and number of teeth. Toothbrushing frequency was also important for permanent teeth.

CONCLUSIONS

Within this population of New England children with unmet oral health needs, significant differences were apparent between rural and urban children in the extent of untreated dental decay. Results indicate that families who agree to participate in programs offering reduced cost or free dental care may present with varying amounts of dental need based on geographic location.

A Dose-Effect Analysis of Children's Exposure to Dental Amalgam and Neuropsychological Function

BACKGROUND

The New England Children's Amalgam Trial (NECAT) was a five-year randomized trial of 534 6- to 10-year-old children that compared the neuropsychological outcomes of those whose caries were restored using dental amalgam with the outcomes of those those whose caries were restored using mercury-free resin-based composite. The primary intention-to-treat analyses did not reveal significant differences between the treatment groups on the primary or secondary outcomes of the administered psychological tests: Full-Scale IQ score on the Wechsler Intelligence Scale for Children-Third Edition, General Memory Index of the Wide Range Assessment of Memory and Learning, and Visual-Motor Composite of the Wide Range Assessment of Visual Motor Abilities.

METHODS

To determine whether treatment group assignment, a dichotomous measure of exposure, was sufficiently sensitive to detect associations between mercury exposure and these outcomes, the authors conducted analyses to evaluate the associations between the primary and secondary outcomes and two continuously distributed indexes of potential exposure, surface-years of amalgam and urinary mercury excretion.

RESULTS

Neither index of mercury exposure was significantly associated with any of the three outcomes.

CONCLUSIONS

The authors found no evidence that exposure to mercury from dental amalgam was associated with any adverse neuropsychological effects over the five-year period after placement of amalgam restorations.

CLINICAL IMPLICATIONS

Analyses of the outcomes of the NECAT study indicate that use of dental amalgam was not associated with an increase in children's risk of experiencing neuropsychological dysfunction.

Methamphetamine exacerbates the toxic effect of kainic acid in the adult rat retina

The recreational use of the psychoactive drug, methamphetamine has increased markedly over the last three decades. It has long been known that this drug has detrimental effects upon the mammalian brain monoaminergic system, but the long- or short-term effects on the retina, a neurological extension of the central nervous system, have received little attention. The aim of this study was, therefore, to determine whether intraocular injection of methamphetamine (MA) is toxic to the healthy adult rat retina and to analyse its effects on the compromised retina after an injection of the ionotropic glutamate receptor agonist, kainate, which is known to cause retinal neuropathology. The equivalent of 1 mM (in the vitreous humour) MA and/or kainate (40 microM) were injected intravitreally. Flash electroretinograms (ERGs) were recorded before and 2 and 4 days after treatment. Five days after treatment, animals were killed and the retinas analysed either for the immunohistochemical localisation of various antigens or for electrophoresis/Western blotting. Some animals were kept for 19 days after treatment and the retinas analysed for tyrosine hydroxylase immunoreactivity. No differences could be found between vehicle- and MA-treated retinas with respect to the nature or localisation of either tyrosine hydroxylase immunoreactivity after 5 or 19 days or other antigens after 5 days. Moreover, the normal ERG and GFAP and calretinin protein antigens were unaffected by MA. Kainate treatment, however, caused a change in the ERGs after 2 and 4 days, an alteration in every antigen localised by immunohistochemistry and an increase in the retinal levels of calretinin and GFAP proteins. Significantly, the changes seen in the b-wave amplitude and implicit time of the ERG after 4 days and the increased level of GFAP protein after 5 days following kainate treatment were enhanced when MA was co-injected. Intravitreal injection of methamphetamine had no detectable detrimental effect on the normal adult rat retina but exacerbated the damaging effects of kainic acid. Such data suggest that a neurotoxic effect of MA may be more obviously illustrated when the tissue is already compromised as occurs in, for example, ischemia.

Computer-based sessions in radiological anatomy: one year's experience in clinical anatomy

In the last curricular review (1995/96) radiological anatomy was introduced as an innovation in the program of the course of clinical anatomy of the Medical School. Since computer-based media are known to facilitate the understanding of the human body, computer technology was selected in the academic year of 1997/98 as an elective educational tool to teach radiological anatomy. CD-ROMs were introduced as additional instructional resources in 1997/98. This technology aimed to provide educational support to the program, namely, to the sessions of radiological anatomy in each section of the course: head, neck, thorax, abdomen, pelvis and perineum. A questionnaire was designed to evaluate the opinion of the students enrolled in this course, focusing on the teaching sessions of radiological anatomy. Of 152 students, 135 (88.8%) returned the questionnaire. To describe the relationship between the value of this technology and several aspects of its organisation and adequacy, the Spearman rank correlation coefficient was used; canonical correlation was used for the various practical sessions. The comments of students were very positive emphasising the quality of the media, organisation of the course, immediate feedback, degree of interactivity and simplicity of use; they suggested a larger facility for the computers and acquisition of more programs and hardware. The positive evaluation of the use of the CD-ROMs in clinical anatomy allows us to foresee the formal integration of these instructional tools in the whole course, and not to restrict its use to specific units within the course.

Neonatal methamphetamine in the rat: evidence for gender-specific differences upon tyrosine hydroxylase enzyme in the dopaminergic nigrostriatal system

Methamphetamine (Meth) neurotoxicity upon the mesencephalic dopaminergic systems was demonstrated in the adult, both in humans and in experimental models. In the rat, the development and maturation of the dopaminergic systems is accomplished during the first month of postnatal life, a period of particular vulnerability to environmental influences. In this study, the effect of Meth exposure during the first month of life was assessed in the nigrostriatal dopaminergic system of the rat. For this purpose, Wistar rat litters were culled to 8 pups, retaining preferentially 4 males and 4 females, which, in the day following birth (postnatal day 1, PND1), were randomly attributed to either the Meth or control group. Meth-groups were administered 10 mg of (+)-methamphetamine hydrochloride/kg body weight/day, subcutaneously, twice daily, from PND1 until PND29; control groups received isovolumetric doses of saline. Animals were sacrificed at PND30. Males exposed to Meth during the first month of life had increased tyrosine hydroxylase (TH) activity both in the caudate-putamen and substantia nigra. Males also had increased nigral TH mRNA levels, as assessed by in situ hybridization. These effects did not exist in females. These results support the evidence that Meth exposure during the first month of life in the rat has a gender-specific stimulatory effect upon the maturation of TH, the key enzyme for dopamine biosynthesis in the nigrostriatal dopaminergic system.

Effects of neonatal exposure to cocaine in the development of the neurotransmitters retinal systems: an immunocytochemical and neurochemical study

The visual system of rodents is affected if exposure to drugs, e.g., cocaine, occurs during prenatal or early postnatal development. This study aims to evaluate, in an experimental model of neonatal exposure to cocaine in the rat, the immunocytochemical expression of tyrosine hydroxylase in the retina and the levels of different neurotransmitters and its metabolites. Male Wistar rats were given 15 mg cocaine hydrochloride/kg body weight/day, subcutaneously, in two daily doses, from the day after birth (PND1) to PND6, 13, and 29. Controls were given 0.9% saline. Groups of rats were perfused at PND7, 14, and 30 with fixative, and the retinas were processed as wholemounts, and immunostained with the antibody anti-TH. Other groups were decapitated, and the retinas were dissected and processed by high performance liquid chromatography with electrochemical detection (HPLC-EC) for determination of dopamine and metabolites (DOPAC and HVA). A reduction in the retinal surface area was detected in the PND30 cocaine group, and a decrease in the density of the small TH-IR cells was found in the PND14 cocaine group although not reaching significant levels. The other quantitative parameters did not differ between the control and cocaine groups. The levels of neurotransmitters did not significantly differ between the groups at any age. These results show a differential vulnerability of the dopaminergic system of rats exposed neonatally to cocaine when compared with the effects found after prenatal exposure to the same drug.

Handouts as an educational support for the teaching/learning program in clinical anatomy

Handouts were developed to support the program of Clinical Anatomy in the Medical School of Porto, and since 1996/97 alterations have been made to improve their format and content with our educational objectives in mind. A questionnaire was designed to evaluate the opinion of second-year medical students enrolled in the program. Students were asked about their approval of the way handouts were organized and their usefulness, especially for lectures and practical sessions on physical examination, sectional and imaging anatomy, anatomical variations and malformations and case studies. Of 152 students, 138 (90.8%) returned the questionnaire. To describe the relationship between the value of handouts and several aspects of their organization and adequacy, the Spearman rank correlation coefficient was used for lectures, and canonical correlation for the various practical sessions. Students fully approved the way the handouts of lectures and practical sessions were organized (81.8% and 87%, respectively), their presentation (74.6% and 86.2%), relevance (88.3% and 85.5%), usefulness in understanding the lectures (77.6%) and their value in preparing for practical sessions (83.3%). Handouts were considered highly useful for case studies (90%), physical examination (81.9%) and sectional anatomy (65.7%). Students stating a higher degree of utility of the handouts emphasized that they were useful-indeed essential-in preparing for sessions, and noted their objectivity. The evaluation of the handouts was highly favorable and showed that they can be used as a guide through the complexities of an innovative program of Clinical Anatomy.

Spinal cord injury and psychological response

Psychological adjustment and psychopathological morbidity issues during rehabilitation of patients with spinal cord injury, have been documented in international literature. However, most authors are faced with methodological difficulties, and results are contradictory. In this prospective study, the first to be made in the Portuguese population, a sample of 65 patients being treated in a rehabilitation unit during the years of 1993, 1994 and 1995, was obtained. The authors study the type of psychological response, when it does occur, which personality traits point to less suffering, which coping mechanisms are used by the better adjusted patients and the differences between the scores of paraplegic and quadriplegic patients. Two assessments were made. The following assessment instruments were used: an anamnestic data questionnaire, the SCL-90-R (Derogatis, 1983), the EPI (Eysenck & Eysenck, 1984), the Coping Styles Evaluation Scale (Figueira, 1990). The second assessments were carried out with the SCL-90-R only. The findings indicate that psychopathological scores consistent with depression occurred in 60% of patients if we consider any evaluation. Sleep disturbances, suicide ideation and guilt occurred in the same proportion. In 33% of them, we found persistent depressive scores in the two assessments. The authors find a highly significant positive correlation between psychopathology and neuroticism. On the contrary, the extroversion dimensions of EPI seem to be a good prognosis predictive factor as far as the occurrence of psychopathology is concerned. No differences in the psychopathological response were found concerning the paraplegic-quadriplegic situation.

Developmental exposure to methamphetamine: a neonatal model in the rat

Taking into account that methamphetamine (MA) is a popular recreational drug among young adult women, i.e., in gestational age, the present model aims to assess the effects of its exposure during development. In this experimental model, MA effects are assessed in the rat during the first month of life, regarding both general growth parameters, and gross morphological effects in the retina as part of the evaluation of sensory systems. Experimental animals were obtained from 60-day-old nulliparous females. Litters were culled to 8 pups (4 males and 4 females, whenever possible), individually marked and weighed every two days. Experimental groups received 10 mg (+)methamphetamine hydrochloride kg body weight/day, subcutaneously, twice daily, from postnatal day (PND) 1 to the day before sacrifice; control groups received isovolumetric doses of saline, in the same protocol. Pups were weaned on PND 21. Groups were sacrificed on PND 5, 7 and 30. Animals exposed to MA presented increased percentage of retinal hemorrhages (18, 7 and 11% on PND 5, 7 and 30, respectively) compound to control groups (2% on PND 7, 0% on PND 5 and 30). On PND 30, the mean body weight of males exposed to MA was 75% of the mean weight of male controls, whereas for females, mean body weights were 70% of those of female controls. These findings support the view that developmental parameters in the rat are deleteriously affected by early exposure to MA.

Differential effects of prenatal exposure to cocaine and amphetamine on growth parameters and morphometry of the prefrontal cortex in the rat

The purpose of this study was to investigate the differential effects of prenatal exposure to psychostimulants, e.g., cocaine or amphetamine, on basic growth parameters and morphometry of the medial prefrontal cortex of the rat. A group of pregnant Wistar rats was given 60 mg/kg body weight/day of cocaine hydrochloride and another group 10 mg/kg body weight/day of d-amphetamine sulfate, subcutaneously, from gestational days 8 to 22. Control groups of pregnant rats were pair-fed; litters were culled to eight pups (4 males and 4 females) weighed every other day until postnatal day 30 and every week until day 90. The body weight growth patterns modelled by a Gompertz curve were different in rats prenatally exposed to the two psychostimulants. Rats exposed to amphetamine had on average a slower growth than those exposed to cocaine, reaching an identical estimated adult weight. Allometric relationships between forebrain and body weight and cerebellum and body weight were described by two distinct postnatal growth phases that are different among the experimental groups. In the comparison of the two psychostimulants the relative cerebellum/body growth is lower in the offspring of the cocaine group than in the amphetamine group between PND14-PND30; between PND30-PND90 the relative growth rate is considerably higher in the offspring of the cocaine dams compared to that of the amphetamine dams. Groups of perfused animals were selected at postnatal days 14 and 30 to analyze the morphometric organization of the medial prefrontal cortex. In serial celloidin sections the volumes of the prefrontal cortex were determined; the number of neurons per unit volume of reference area was calculated using the stereological technique of the disector. The changes found in the morphometric parameters show a catch-up at postnatal day 30 of the "increased" density of neurons of the medial prefrontal cortex found at postnatal day 14. These data show differential growth patterns of offspring from cocaine- and amphetamine-exposed rats; a delayed development in the achievement of normal morphometric parameters of neurons in the prelimbic subarea of the medial prefrontal cortex occurs in the prenatally amphetamine-exposed offspring at early ages, and a catch-up is found after the first month of life. Complementary studies are needed to assess whether these changes have functional implications in the rats exposed prenatally to psychostimulants.

Development of the eye after gestational exposure to cocaine. Vascular disruption in the retina of rats and humans

Clinical and basic research in the area of drugs of abuse are of utmost importance since they provide the necessary background for health programs in one of the main problems of contemporary society. The available data in this field demonstrate that acute, subacute and/or chronic abuse of illicit drugs, e.g., cocaine, alters the neurochemistry and functioning of the neural circuitries. Although recent works demonstrated that the visual system is lesioned after exposure to cocaine during the active periods of development, no studies have provided detailed information on the effects of these substances on the development of this sensory system. The present paper will report: 1) the vulnerability of the developing visual system to gestational exposure to cocaine; 2) the effects of cocaine in the visual system during the more active periods of development in humans and, as far as possible, the establishment of homologies with animal models where exposure is made in corresponding periods of human gestation, and 3) the characterization of the vascular disruption caused by ischemic/hypoxic mechanisms. The clinical study focused the ophthalmologic evaluation of newborns exposed in utero to illicit drugs. Newborns exposed to cocaine in utero showed marked vascular disruption in the retina: superficial and deep hemorrhages that, although morphologically similar to neonatal retinal hemorrhages, presented a longer reabsorption time when compared with the neonatal hemorrhagic lesions due to birth trauma in the general population. Prolonged eyelid edema was also a prominent finding. The animal study was conducted in Wistar rats exposed prenatally (gestational days 8 to 22) and postnatally (postnatal days 1-6, 1-13 and 1-29) to 60 mg/kg body weight/day and 15 mg/kg body weight/day, respectively, to cocaine hydrochloride administered subcutaneously; control groups included pair-feeding during the same experimental periods. Similar alterations to those observed in the newborns where exposure to cocaine was affirmative, were found: intraretinal hemorrhages allied to signs of chronic ischemia both in the outer retina-photoreceptor rosettes and in the inner retina-epiretinal glial membranes. Taking into consideration that the visual system is one of the more important sensory systems, the identification and characterization of these alterations, the similarity between animal and human findings, and their relation with cocaine per se, can provide a sound data base for illicit drug prevention programs.

Effects of prenatal exposure to amphetamine in the medial prefrontal cortex of the rat

This study was designed to investigate the effects of prenatal exposure to amphetamine in the organization of the medial prefrontal cortex of the rat, by an evaluation of growth, morphometric and neurochemical parameters. Pregnant Wistar rats were given 10 mg/kg body weight/day of D-amphetamine sulfate, subcutaneously, from gestational days 8 to 22. Control groups of pregnant rats were injected with saline, pair-fed or non-manipulated; litters were culled to eight pups (four males and four females), weighed every other day until postnatal day 30 and every week until day 90. The Gompertz model was used to study body weight evolution and the estimated growth parameters were not significantly different in the experimental groups. At postnatal days 14 and 30, the volumes of the prefrontal cortex, the fraction of neuropile occupied by neurons and the number of neurons per unit surface are were determined. The number of neurons per unit volume of reference area was calculated using the stereological technique of the dissector. For neurochemical analysis, the medial prefrontal cortex was dissected to measure the concentration of dopamine, serotonin and their metabolites. The allometric relationship of forebrain/body growth pointed to a mechanism of sparing and compensatory growth in the amphetamine exposed group. The changes found in the number of neurons per unit volume at postnatal day 14 show a catch-up at postnatal day 30. A decrease in serotonin levels was found in the amphetamine group compared with the pair-fed control, which was reflected in the ratio of serotonin to its metabolite, 5-hydroxyindolacetic acid. These changes, whether permanent or transitory, raise the possibility that some of the effects of prenatal exposure to amphetamine may be due to modifications in the neurotransmitter levels of serotonin.

The effects of prenatal exposure to cocaine on the dopaminergic cells in the rat retina. An immunocytochemical and neurochemical study

There is a growing consensus that the development of the eye is affected by prenatal exposure to cocaine. Considering that the retina is affected by prenatal cocaine exposure, that this drug affects the dopaminergic systems, that the dopaminergic cells in the retina show a well-defined pattern of development and that they can be specifically stained in wholemounts by the antibody anti-tyrosine hydroxylase (TH), this study was undertaken to evaluate the effects of in utero cocaine exposure on the dopaminergic cells of the rat retina. Pregnant Wistar rats were given 60 mg (kg body weight)-1 day-1 of cocaine hydrochloride, subcutaneously, from gestational days 8 to 22. Control groups of pregnant rats were pair-fed. At PND14, 30 and 90, male offspring from different litters were perfused with fixative and the retinas processed as wholemounts and immunostained with the antibody anti-TH. Rats from other groups were decapitated at the same post-natal ages, the retinas dissected and processed by neurochemical techniques to measure the concentrations of dopamine, its metabolites and the turnover of dopamine. There was a significant increase of the retina surface area between PND14-30 in the control group, which was not found in the cocaine group. The density of the immunostained small TH cells was lower in the cocaine groups. No drug-effects were detected in the density of the large TH cells. The densities of the total large and small cells in the superior, inferior and nasal hemiretinas were similar to those found in the whole retinas; however, in the temporal hemiretinas of the cocaine groups, the density of the large TH cells was higher and of the small TH cells was lower than in controls, resulting in an absence of effects on the total density of TH-cells in this hemiretina. A transient increase in the level of dopamine metabolite (DOPAC) and of the turnover of dopamine at PND14 was detected in the cocaine groups. All quantitative parameters reached normal values, in all groups, at PND90. These results show that, during the critical periods in which catecholamines can influence the development of neurons, cocaine transiently affects the pattern of dopaminergic neurons in the retina. This may have functional importance due to the role of this neurotransmitter as a regulatory and/or trophic factor in developing neuronal circuitries.

Retinal hemorrhages associated with in utero exposure to cocaine. Experimental and clinical findings

BACKGROUND

The use of drugs of abuse--e.g., cocaine--during pregnancy has been associated with abnormalities of the visual system. The authors studied the effects of prenatal exposure to drugs of abuse, especially cocaine, on the vascular system of the retina in newborn infants and in an experimental model in the rat.

METHODS

The animal study was conducted in pregnant Wistar rats injected subcutaneously with cocaine hydrochloride (60 mg/kg body weight/day) from gestation days 8 to 22. Male offspring were killed at postnatal days 7, 14, and 30 and perfused with fixative, and the retinas were dissected and processed for microscopic observation. The ophthalmologic observations were conducted in a population of newborn infants born to women who abused many drugs during pregnancy and in a control group of women with no history of illicit drug use.

RESULTS

Vascular disruptive lesions were seen after prenatal exposure to cocaine in the rat: round intraretinal hemorrhages, ischemic and hypoperfused areas located at the temporal part and often extending from the posterior pole to the periphery of the retina. The ophthalmologic observation of the newborns showed a higher incidence of vascular disruptive lesions in infants in whom exposure to drugs of abuse was affirmative during pregnancy. In the cases in which cocaine consumption was reported, they consisted in blot full-thickness hemorrhages with rounded domed contours suggestive of venous occlusion and retinal ischemia, very similar to the lesions seen in the animal model. These hemorrhagic lesions, morphologically similar to neonatal retinal hemorrhages, had a higher incidence than in controls; they also took longer to resolve when compared with the reabsorption time of the neonatal hemorrhages due to birth trauma and the hemorrhagic lesions in newborns of mothers in whom consumption of other drugs--but not cocaine--were reported.

CONCLUSION

A topographic and morphologic parallelism can be established between the retinal vascular alterations found in humans consuming cocaine and in the animal model of prenatal exposure to this drug of abuse; although findings from animal studies may be difficult to apply directly to humans, these data strongly support that cocaine can be a causal factor for the occurrence of retinal vascular disruption in newborns.

Effects of prenatal cocaine exposure in the photoreceptor cells of the rat retina

Despite the increasing evidence of eye abnormalities, the effects of prenatal exposure to cocaine on the visual system are still poorly understood. This study was aimed at analyzing the qualitative and quantitative organization of the retinal photoreceptor cells (PR) and outer nuclear layer (ONL) after prenatal exposure to cocaine in the rat. Pregnant Wistar rats were given sc injections of cocaine hydrochloride (60 mg/kg body wt/d) or saline or were not manipulated; analyses were performed in the 14- and 30-d-old male offspring. Radial semithin and ultrathin sections of epon-embedded flat mounts of the retina showed displaced PR-like cells in the inner nuclear layer (INL), picnotic PR nuclei in INL, and ONL, and retinal PR rosettes and outer-segment debris in the subretinal space. The quantitative study showed an increased density of PR-like nuclei in the INL in PND14 cocaine-treated rats that were within normal values at PND30; no changes were detected in the PR mean nuclear diameter and in the packing density of PR nuclei in the ONL. These data constitute the first morphological demonstration of photoreceptor damage after prenatal cocaine-exposure probably owing to a direct action of the drug and/or to the cocaine-induced ischemia/hypoxia.

Effects of prenatal cocaine exposure in the retinal ganglion cell layer of the rat. A morphometric analysis

To study the effects of prenatal cocaine-exposure on the developing retinal ganglion cell layer of the rat, female Wistar rats were administered subcutaneously (sc) cocaine hydrochloride (60 mg/kg body wt/d) or saline, or were not manipulated from gestational d 8-22. Male offspring were sacrificed at postnatal day 14 and 30. Radial semithin sections of epon-embedded flat mounts of the retinal quadrants were used to evaluate the following parameters along the centroperipheral axis: 1. Thickness of ganglion cells plus nerve fiber layer; 2. Nuclear size of ganglion cell layer neurons; and 3. Linear density (number per unit length) of ganglion cell layer neurons. To study the effects of cocaine and age on the retinal areas (temporal/nasal, dorsal/ventral), a repeated measures analysis of variance was used for each of the parameters mentioned above. All parameters were affected by prenatal exposure to cocaine. The thickness of the ganglion cell plus nerve fiber layer was reduced in cocaine-exposed rats in comparison with the saline group. Nuclear diameters were smaller in the cocaine than in the saline and control groups. The linear density was higher in the cocaine-exposed group than in the control and saline groups. The age-dependent decrease in the linear density from postnatal day 14-30 was higher in the cocaine-exposed rats than in the saline group; the decrease in the linear density along the centroperipheral axis found in both the control and saline groups was not significant in the cocaine-treated group. These morphometric findings strongly support the view that prenatal cocaine-exposure induces marked changes in the organization of the developing retina.

Effects of prenatal cocaine exposure in the prefrontal cortex of the rat. A morphometric evaluation

This work was undertaken in order to assess the organization of the prelimbic area of the medial prefrontal cortex of rats exposed prenatally to cocaine. Pregnant Wistar rats were assigned to the following groups: 1. Cocaine--60 mg/kg body wt/d sc, from gestational days 8-22; 2. Saline; 3. Pair-fed; and 4. Nonmanipulated. Male offspring were perfused on postnatal days 14 and 30. Six brains per group and per age were embedded in celloidin to calculate the volumes of the prelimbic area; sections from the other six brains were embedded in resin and processed for electron microscopy. Using semithin sections (2 microns) of layers II-III and V-VI, the following parameters were calculated: 1. The fraction of the neuropil occupied by neurons (VV); 2. The packing (NA) density; and 3. The numerical (NV) density. Qualitative alterations consisted of dispersed profiles of degenerated neurons and dendrites in the medial prefrontal cortex. No significant differences were found in the gross morphometric parameters when the cocaine group was compared with the other groups. A high interanimal variation was shown in the prelimbic volumes of postnatal day (PND) 14 cocaine-treated rats, and a a decrease in volumes was detected at PND30. Although there are some alterations in the main afferent cortical target area for dopaminergic input, its gross morphometric parameters do not seem to be sufficiently affected to account for the behavioral alterations referred to as being dependent on this brain region.

Effects of prenatal cocaine exposure on postnatal growth patterns of male Wistar rats

The purpose of this study was to investigate basic parameters regarding the postnatal effects of prenatal exposure to cocaine. Timed-pregnant Wistar rats were injected SC with 60 mg/kg body weight/day of cocaine from gestational day 8 to 22. Control females were nonmanipulated and given food and lib; saline females received saline injections and pair-fed received saline and were nutritionally controlled to the cocaine-treated rats. Litters were restricted to 8 pups, weighed every other day until postnatal day (PND) 30 and every week from PND 30 to PND 90. The rats were perfused at PND 14, 30, and 90. The adequacy of adjustment of the logistic and Gompertz models to the body weights of the offspring was tested for the whole experimental period. The results from the Gompertz curve showed a higher growth rate and less time to reach 37% of expected mature body mass for the offspring of cocaine and pair-fed dams as compared with that of control and saline dams. No significant differences in the estimated adult weight were found among the experimental groups. The allometric relationship between forebrain and body weight is described by two postnatal growth phases with a first phase of rapid growth between PND 14 and 30 and a decelerating phase between PND 30 and 90. This relationship was not different among the experimental groups; however, the cocaine and pair-fed offspring showed a constant deficit in the forebrain weight as compared with the control and saline offspring.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of glial fibrillary acidic protein in the rat retina after exposure to psychostimulants

PURPOSE

Neonatal exposure to psychostimulants is known to produce morphologic alterations in the developing visual system of rats. This study was designed to evaluate the extent of retinal astrocytic response by using the astrocyte localized protein, glial fibrillary acidic protein, after neonatal exposure to cocaine and amphetamine.

METHODS

Male Wistar rats were given 15 mg/kg body weight/day of cocaine hydrochloride, subcutaneously, from postnatal days 0 to 6, 13, and 29 and were killed at postnatal days 7, 14, and 30; other rats received 10 mg/kg body weight/day of d-amphetamine sulfate following the same protocols. Control rats were given saline or were not manipulated. After transcardiac perfusion with 4% paraformaldehyde whole mounts of flat retinas were processed for glial fibrillary acidic protein immunohistochemistry. Retinas displaying lesions from the amphetamine groups were processed for electron microscopy; vertical semithin and ultrathin sections were observed.

RESULTS

In cocaine-treated rats extensive sheets of proliferating astrocytes presenting a preferential peripheral localization could be identified. In the amphetamine-exposed rats an enhanced expression of glial fibrillary acidic protein was detected in widespread "loci" of astrocytes observed throughout the whole retinal surface; at postnatal day 30 sheets of proliferating astrocytes could also be identified.

CONCLUSION

Exposure to psychostimulants during active development induced different types of astrocytic responses in the retina, which, as an end result, can lead to functional changes due to the disruption of the retina structural organization.

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)

Primary lipid keratopathy: a morphological and biochemical assessment

Images

Aqueous outflow system in familial amyloidotic polyneuropathy, Portuguese type

Familial amyloidotic polyneuropathy (FAP) is a hereditary disease which may present a wide range of ocular manifestations. Glaucoma is amongst the most serious complications of FAP. We report the results of ultrastructural study of the trabecular meshwork in a glaucomatous patient with the Portuguese form of FAP. This study showed that there was marked anatomical disruption of the uveoscleral, cornoscleral meshworks and juxtacanalicular tissue characterized by (a) accumulation of amyloid fibrils in the intertrabecular spaces; (b) degeneration of the endothelial cells; (c) homogeneous and/or multilayered plaques of basement membrane-like material loading the intertrabecular spaces or protruding to the lumen of the Schlemm's canal; and (d) degeneration of unmyelinated nerve fibres. These morphological changes and an analysis of the literature suggest that mechanical and neuropathic events can be co-existing factors which enhance the resistance to aqueous humour outflow, leading to increased intraocular pressure and glaucoma in the Portuguese form of FAP.

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)

Morphological changes in the optic nerve after chronic exposure of neonatal rats to cocaine and amphetamine

We determined the effects of cocaine hydrochloride (15 mg/kg body weight/day) or amphetamine sulfate (25 mg/kg body weight/day) on the optic nerve in groups of rats exposed from postnatal day 1 to 30. Qualitative and quantitative studies of cross-sections of the optic nerves showed different patterns of organization, namely the presence of degenerative features in drug-treated animals and significant differences in the proportion of the nerve occupied by glial cells and their processes and nerve fiber bundles. No significant differences of the total number of fibers were found. Taken together, these data indicate that the optic nerve is vulnerable to early exposure to cocaine and amphetamine which cause developmental changes in this link of the visual pathways.

Effects of chronic alcohol intake and withdrawal on the prefrontal neurons and synapses

Previous studies demonstrated that alcohol induces marked deterioration of the cerebral cortex. However, quantitative evaluations of neurons and synapses of the prefrontal cortex from chronic alcohol-fed and withdrawn animals are nonexistent, in spite of the functional implications that can underlie structural changes in this cortical area. To achieve this evaluation, we used groups of rats alcohol-fed for 6, 12 and 18 months, their respective controls as well as groups of rats alcohol-fed for 6 and 12 months and then switched to water for 6 months--withdrawal groups. The thickness of the prelimbic cortical layers I-III was reduced in the alcohol-fed and withdrawal groups. A significant reduction in the density of cells was found, which was more marked after withdrawal. Conversely, the density of synapses increased after alcohol exposure and withdrawal; such numerical shifts lead to a significant increase in the synapse-to-neuron ratio. These results indicate that the cortical circuitry of the prelimbic cortex is vulnerable to prolonged periods of alcohol exposure and withdrawal and allow to advance the view that the alterations can induce functional implications.

Metric analysis of hippocampal granule cell dendritic trees after alcohol withdrawal in rats

It was previously demonstrated that after prolonged alcohol consumption, dendrites might display either degenerative or plastic changes according to the central nervous system areas studied. Furthermore, and rather unexpectedly, we also found that withdrawal from alcohol led to a decrease of the relative number of granule cells in the fascia dentata. Thus, it seemed worthwhile to quantify, using a semiautomatic measuring system, the dendritic arborizations of hippocampal granule cells of rats alcohol-fed for 12 months followed by 6 months of abstinence and compare the results with age-matched control and alcohol-fed groups. The results indicate smaller dendritic trees in the abstinent group when compared with the higher values of the dendritic parameters found in alcohol-fed rats.

Hippocampal mossy fiber-CA3 synapses after chronic alcohol consumption and withdrawal

A quantitative study of the CA3 pyramidal cells and of the mossy fiber-CA3 synapses (MF-CA3) of the rat hippocampal formation was performed in rats alcohol-fed for 6, 12 and 18 months and respective age-matched controls. Additional groups alcohol-fed for 6 and 12 months and withdrawn for 6 months were also studied. The numerical densities of the CA3 pyramids and of the synapses were calculated applying the disector method to adjacent sections of the CA3 pyramidal cell layer and the stratum lucidum respectively. The results showed a progressive loss of pyramidal cells in alcohol-treated and withdrawal groups and a significant decrease of MF-CA3 synapses after 18 months of alcohol feeding. Taking into account that both hippocampal granule and CA3 pyramidal cells are reduced, the maintenance of the relative number of MF-CA3 synapses in 6- and 12-month alcohol-fed rats suggests the formation of new contacts. The increased proportion of the MF plasmalemma occupied by synapses can also be interpreted as an additional compensation process. These data show that MF-CA3 synapses display plastic and degenerative changes after chronic alcohol consumption and withdrawal which presumably will lead to functional modifications of the hippocampal circuitry.

Cell loss in the cerebellum and hippocampal formation of adult rats after long-term low-protein diet

Whereas quite a number of previous reports have shown that the developing brain is vulnerable to protein deprivation, the mature CNS is usually considered resistant to this condition. To explore this assumption the present experimental model was built on groups of 2-month-old rats fed with a low-protein diet (8% casein) for 6, 12, and 18 months and respective age-matched controls fed for the same periods with a standard laboratory chow (27% casein). The numerical density of cerebellar granule cells was estimated using three different stereological procedures (classical, unfolding, and disector). By all methods a significant cell loss was demonstrated. In the hippocampal region the numerical densities of dentate gyrus granule cells and the CA3 pyramidal cells were estimated using the unbiased disector method. A significative and progressive loss of neurons was likewise found. The occurrence of cell loss after lengthy periods of undernutrition in adulthood is thus an issue of paramount importance if extrapolation can be made to the human brain.

Granule cell loss and dendritic regrowth in the hippocampal dentate gyrus of the rat after chronic alcohol consumption

The effects of chronic alcohol consumption (CAC) on the relative number of dentate gyrus granule cells and their dendritic trees, were studied in animals fed alcohol for 6, 12 and 18 months and in their respective controls. The granule cell density was estimated with the unbiased disector method. Following 6 months of alcohol consumption, the thickness of the dentate gyrus granular layer and the relative number of dentate granule cells were significantly decreased when compared with controls. The granule cell dendritic arborizations showed an increase of their dendritic extent in alcohol-treated rats. No significant differences were found in the density of dendritic spines between alcohol-fed and control animals. These results indicate the existence of hippocampal granule cell dendritic regrowth in alcohol-fed rats, probably occurring as a compensatory response to the granule cell deficit which follows the alcohol-induced granule cell degeneration. These degenerative and regenerative changes might have functional implications for the organization of the synaptic hippocampal circuitry after long periods of alcohol consumption.

Long-term alcohol consumption reduces the number of neuronal nuclear pores. A morphometric study undertaken in CA3 hippocampal pyramids of rats

A close relationship between the number of nuclear pores and the cellular protein synthesis activity is known to exist. Previous biochemical investigations lead to admit that the widespread neuronal alcohol-induced degenerative changes could depend on a decrease in the neuronal protein synthesis. The morphometric analysis made on the nuclear pore complexes of CA3 hippocampal pyramids of long-term alcohol-fed rats fully supports this attractive hypothesis, since it has been found a marked reduction in the number of pores per unit surface area of nuclear membrane, together with a reduction in their total number per nucleus.

Alcohol withdrawal does not impede hippocampal granule cell progressive loss in chronic alcohol-fed rats

Using the unbiased disector method we have shown that chronic alcohol consumption induces a significant decrease of dentate gyrus granule cell density in alcohol-fed rats for 18 months. A still more dramatic reduction was observed in a group of age-matched rats alcohol-fed for 12 months and switched to water for 6 months (recovery group). These results indicate that a progressive neuronal loss of the hippocampal granule cells in not impeded after cessation of alcohol intake. It is thus suggested that once the mechanisms underlying the alcohol-induced neuronal degeneration are triggered, they continue to act even after withdrawal.

Lysosomal abnormalities in the pyramidal cells of the rat medial prefrontal cortex after chronic alcohol consumption and withdrawal

Previous investigations have demonstrated that prolonged alcohol consumption induces alterations of the neuronal lysosomal system in the cerebellum and hippocampus. To assess the effects of chronic alcohol consumption and withdrawal in the adult rat prefrontal cortex, we studied the pyramidal cells in the prelimbic area taking into particular account their lysosomal components. Alcohol-fed groups for 6, 12 and 18 months, respective age-matched pair-fed controls, and a 6-month recovery group after 12 months of alcohol consumption were used. No quantitative changes of primary lysosomes were depicted. Transitional forms of these organelles towards lipofuscin granules were more numerous among alcohol-fed and recovery animals. A precocious and progressive accumulation of lipofuscin granules occurred in greater amounts in alcohol-fed animals, increasing with the age and remaining after 6-months of withdrawal. Multivesicular bodies increased in alcohol-fed and recovery animals, displaying an inverse progression relative to the lipofuscin deposition. These results show that chronic alcohol consumption and withdrawal enhance the dynamic potentialities of the cell lysosomal system.

A quantitative study of frontal cortex dendritic microtubules in patients with Alzheimer's disease

The dendritic microtubules (MT) of the frontal cortex layers II and III were studied in 9 patients with Alzheimer's disease (AD) and the results compared with 9 case controls. Dendrites with abnormally oriented MTs and others depleted of these structures were seen. A significant reduction in the number of MTs per unit area was found in AD. It is suggested that microtubular changes in AD can interfere with neuroplasmic transport and thus, be implicated with the dendritic degeneration present in this disease.

Chronic alcohol consumption reduces the cortical layer volumes and the number of neurons of the rat cerebellar cortex

Past work showed that chronic alcohol consumption induces massive degeneration in the rat cerebellar cortex. In order to provide details of these effects, the cortical cell numbers and the cerebellar layer volumes were studied in adult rats fed alcohol for 1, 3, 6, 12, and 18 months and compared with respective age-matched controls. Significant decreases of granular and molecular layer volumes were found after 3 and 6 months of alcohol feeding, respectively. No significant differences were found in the Purkinje cell layer volume. Neuron countings showed that granule cells and molecular layer interneurons were the earliest and most severely affected populations. A decrease in the number of Purkinje cells was observed only after 18 months of alcohol consumption and Golgi cells were not significantly reduced. Thus, we concluded that cerebellar neurons have a selective vulnerability to alcohol which might alter the balance between excitatory and inhibitory limbs of the cerebellar circuitry.

Synapses of the cerebellar cortex molecular layer after chronic alcohol consumption

The cerebellar molecular layer of chronic alcohol treated rats showed degenerated parallel fiber boutons and vacated Purkinje cell spines after 6 months of alcohol feeding; degenerated Purkinje cell dendrites were concomitantly observed. The number of synapses between parallel fibers and Purkinje cell spines decreased after 6 months whereas their mean synaptic diameter increased throughout the experiment. Conversely, synapses between parallel fibers and dendrites of interneurons increased in 18-month alcohol-fed group. Quantifications were done using a discrete unfolding procedure. It was also observed that some parallel fiber terminals simultaneously established synapses with multiple Purkinje cell spines and with dendrites of interneurons. These results were obtained from groups of 6 rats alcohol-fed for 1, 3, 6, 12 and 18 months and compared with age-matched pair-fed controls. Previous reports of alcohol-induced degenerative changes in the adult rat central nervous system were, thus, fully corroborated. Furthermore, there was evidence of remodeling processes pointing to compensatory plastic mechanisms in the cerebellar circuitry albeit not sufficient to overcome its alcohol-induced deterioration.

Haemostatic and antialgic effects of the 25 MV photon beam concentrated dose in the treatment of carcinoma of the cervix

The authors present the results of a preliminary study on the use of a concentrated dose of 13 Gy in 48 hours in the treatment of cancer of the cervix, especially for haemostatic and antialgic purposes and mostly as a first part of a split course of radiotherapy. In 13 patients with early stages of the disease, the method was used as an emergency treatment with good response in 84.6% of the cases without serious complications. In 43 patients with advanced disease, the concentrated dose was generally repeated for palliation and relieved symptoms in about 72% of the cases but with complications in 16.3%. The authors recommend this method only when absolutely necessary to stop severe haemorrhage and suggest that patients with good response to the first flash course should continue treatment with conventional fractionation, bearing in mind the tolerance of the normal tissues.

Alzheimer's disease: maintenance of neuronal and synaptic densities in frontal cortical layers II and III

Neuronal loss and alterations of the cortical neuropil were previously described on necropsic material from patients with senile dementia of the Alzheimer type, and the results compared to age-matched case controls. In frontal cortex biopsic material from our patients with Alzheimer's disease, the numerical densities of neurons and synapses were not significantly different from controls, indicating that changes in the highest cognitive functions might not depend on a generalized loss of neurons and synapses and that quantitative morphological differences may exist between Alzheimer's disease and senile dementia of the Alzheimer type.

Chronic alcohol consumption induces plastic changes in granule cell synaptic boutons of the rat cerebellar cortex

The reduction of cerebellar cortex molecular layer afferents, as a consequence of an alcohol-induced granule cell degeneration, is followed by a remodeling activity which leads to marked structural changes. Using Golgi, ultrastructural and combined Golgi-ultrastructural methods, it was evaluated the role played by granule cell synaptic boutons in this plastic process and, furthermore, determined whether there were differences between the boutons located in the ascending portions of the axons and those belonging to parallel fibers. No significant differences were found in the number of boutons per unit length of axon when the alcohol-fed animals were compared to the controls, despite a significant increase in the volumetric density of nerve terminal profiles after 12 months of alcohol intake. This increase is likely to depend on variations in the size of the nerve terminals rather than on their number.

Morphological evidence of climbing fiber plasticity after long-term alcohol intake

The morphological effects of long-term alcohol consumption on the climbing fiber terminals of the cerebellum of adult rats were studied in groups of controls and animals fed a 20% aqueous alcohol solution for 1, 3, 6, 12, and 18 months. Following 12 months of alcohol consumption, vacated postsynaptic sites on Purkinje cell spines from large dendrites (the usual postsynaptic targets for climbing fiber terminals) were seen. Concomitantly, an increased number of climbing fiber profiles were observed in the inner third of the molecular layer. Their volumetric density (Vv) was significantly increased in 12 and 18-month alcohol-fed groups. Along with these findings, large numbers of climbing fiber terminals were seen in the outer third of the molecular layer, synapsing with Purkinje cell spines. The data show that climbing fiber terminals under these experimental conditions display structural plastic capabilities which presumably result in functional modifications on the cerebellar circuitry.