Flúor em chuva simulada: sintomatologia e efeitos sobre a estrutura foliar e o crescimento de plantas arbóreas

Os objetivos deste trabalho foram: caracterizar os efeitos do flúor em espécies arbóreas nativas, nos estádios de plântula e muda; identificar injúrias provocadas pelo flúor na estrutura da lâmina foliar da espécie mais sensível; fornecer subsídios para seleção de características a serem utilizadas na bioindicação e contribuir com informações sobre a resistência ou tolerância das plantas, visando ao reflorestamento de áreas impactadas pela chuva com flúor. As espécies analisadas foram Gallesia gorazema Moq. (Phytolaccaceae), Genipa americana L. (Rubiaceae), Joannesia princeps Vell. (Euphorbiaceae), Peltophorum dubium (Spreng.) Taub. (Leguminosae, Caesalpinioideae) e Spondias dulcis Forst. f. (Anacardiaceae). Plântulas e mudas dessas espécies, provenientes do Parque Estadual do Rio Doce (MG), foram submetidas a 20 min diários de chuva com flúor (30 mg.L-1), por 10 dias consecutivos. Necroses apicais e marginais foram observadas em todas as espécies analisadas, logo após a primeira chuva simulada. S. dulcis, no estádio de muda, foi a espécie mais sensível ao flúor, pois apresentou extensas necroses com apenas dois dias de tratamento, enquanto que G. americana foi a espécie mais resistente. Nas mudas, as espécies que acumularam mais flúor foram também as que apresentaram maior sensibilidade a esse poluente; essa relação não foi verificada nas plântulas. A concentração de flúor utilizada promoveu alterações drásticas na lâmina foliar de S. dulcis com extensas áreas necrosadas, danificando toda a sua estrutura anatômica. A sensibilidade ao flúor observada em S. dulcis indica que essa espécie apresenta potencial para ser usada como bioindicadora. Entretanto, estudos detalhados serão necessários para a melhor caracterização das respostas de S. dulcis ao flúor visando a sua utilização em programas de biomonitoramento ambiental.

Yksilöarvot, konformisuus, sitoutuminen ja vastavuoroisuus yritysarvojen toteutumisen selittäjinä

Yritysarvojen toteutumisesta ei raportoidun tieteellisen tutkimuksen perusteella ole toistaiseksi tehty empiiristä tutkimusta, jossa yritysarvojen toteutumista selittävinä tekijöinä tarkasteltaisiin yhtäaikaisesti henkilöstön yksilöarvoja ja konformisuutta, yritykseen sitoutumista, yritykseltä saatua tukea sekä yritystä kohtaan koettua velvollisuuden tunnetta. Tässä tutkimuksessa analysoitiin edellä mainittujen tekijöiden vaikutusta kohdeyrityksen yritysarvojen toteutumiseen yksilönäkökulmasta sekä koko yrityksen että sen eri toimialojen osalta. Tutkimuksen tavoitteena oli kartoittaa yritysarvojen toteutumiseen vaikuttavia tekijöitä sekä tekijöiden vaikuttavuutta kohdeyrityksessä yritysarvojen toteutumisen tehostamiseksi. Tutkimus toteutettiin tapaustutkimuksena suomalaisessa kaupanalan yrityksessä. Tutkimuksen empiirinen osa toteutettiin yrityksen henkilöstölle suunnattuna strukturoituna kyselynä ja saatu aineisto analysoitiin kvantitatiivisesti. Tutkimustulosten perusteella merkittävimmät tekijät tapausyrityksen yritysarvojen toteutumisessa olivat koettu yritykseltä saatu tuki sekä velvollisuuden tunne yritystä kohtaan. Tarkastellussa aineistossa nämä tekijät selittivät yritysarvojen toteutumisen vaihtelusta 23 - 29 prosenttia toimialasta riippuen. Yksilöarvot ja konformisuus selittivät yritysarvojen toteutumisen vaihtelusta enintään kymmenen prosenttia. Yritykseen sitoutumisen selitysosuus puolestaan oli enintään viisi prosenttia affektiivisen sitoutumisen merkityksen ollessa suurempi kuin jatkuvuuteen perustuvan sitoutumisen.

Chronic imipramine treatment-induced changes in acetylcholinesterase (EC 3.1.1.7) activity in discrete rat brain regions

Cholinergic as well as monoaminergic neurotransmission seems to be involved in the etiology of affective disorders. Chronic treatment with imipramine, a classical antidepressant drug, induces adaptive changes in monoaminergic neurotransmission. In order to identify possible changes in cholinergic neurotransmission we measured total, membrane-bound and soluble acetylcholinesterase (Achase) activity in several rat brain regions after chronic imipramine treatment. Changes in Achase activity would indicate alterations in acetylcholine (Ach) availability to bind to its receptors in the synaptic cleft. Male rats were treated with imipramine (20 mg/kg, ip) for 21 days, once a day. Twenty-four hours after the last dose the rats were sacrificed and homogenates from several brain regions were prepared. Membrane-bound Achase activity (nmol thiocholine formed min-1 mg protein-1) after chronic imipramine treatment was significantly decreased in the hippocampus (control = 188.8 ± 19.4, imipramine = 154.4 ± 7.5, P<0.005) and striatum (control = 850.9 ± 59.6, imipramine = 742.5 ± 34.7, P<0.005). A small increase in total Achase activity was observed in the medulla oblongata and pons. No changes in enzyme activity were detected in the thalamus or total cerebral cortex. Since the levels of Achase seem to be enhanced through the interaction between Ach and its receptors, a decrease in Achase activity may indicate decreased Ach release by the nerve endings. Therefore, our data indicate that cholinergic neurotransmission is decreased after chronic imipramine treatment which is consistent with the idea of an interaction between monoaminergic and cholinergic neurotransmission in the antidepressant effect of imipramine

Acetylcholinesterase activity in the pons and medulla oblongata of rats after chronic electroconvulsive shock

An imbalance between cholinergic and noradrenergic neurotransmission has been proposed for the etiology of affective disorders. According to this hypothesis, depression would be the result of enhanced cholinergic and reduced noradrenergic neurotransmission. Repeated electroconvulsive shock (ECS) is an effective treatment for depression; moreover, in laboratory animals it induces changes in brain noradrenergic neurotransmission similar to those obtained by chronic treatment with antidepressant drugs (down-regulation of beta-adrenergic receptors). The aim of the present study was to determine whether repeated ECS in rats changes acetylcholinesterase (Achase) activity. Achase controls the level of acetylcholine (Ach) in the synaptic cleft and its levels seem to be regulated by the interaction between Ach and its receptor. Thus, a decrease in Achase activity would suggest decreased cholinergic activity. Adult male Wistar rats received one ECS (80 mA, 0.2 s, 60 Hz) daily for 7 days. Control rats were handled in the same way without receiving the shock. Rats were sacrificed 24 h after the last ECS and membrane-bound and soluble Achase activity was assayed in homogenates obtained from the pons and medulla oblongata. A statistically significant decrease in membrane-bound Achase activity (nmol thiocholine formed min-1 mg protein-1) (control 182.6 ± 14.8, ECS 162.2 ± 14.2, P<0.05) and an increase in soluble Achase activity in the medulla oblongata (control 133.6 ± 4.2, ECS 145.8 ± 12.3, P<0.05) were observed. No statistical differences were observed in Achase activity in the pons. Although repeated ECS induced a decrease in membrane-bound Achase activity, the lack of changes in the pons (control Achase activity: total 231.0 ± 34.5, membrane-bound 298.9 ± 18.5, soluble 203.9 ± 30.9), the region where the locus coeruleus, the main noradrenergic nucleus, is located, does not seem to favor the existence of an interaction between cholinergic and noradrenergic neurotransmission after ECS treatment

Prenatal and postnatal depression among low income Brazilian women

Postnatal depression is a significant problem affecting 10-15% of mothers in many countries and has been the subject of an increasing number of publications. Prenatal depression has been studied less. The aims of the present investigation were: 1) to obtain information on the prevalence of prenatal and postnatal depression in low income Brazilian women by using an instrument already employed in several countries, i.e., the Edinburgh Postnatal Depression Scale (EPDS); 2) to evaluate the risk factors involved in prenatal and postnatal depression in Brazil. The study groups included 33 pregnant women interviewed at home during the second and third trimesters of pregnancy, and once a month during the first six months after delivery. Questions on life events and the mother's relationship with the baby were posed during each visit. Depressed pregnant women received less support from their partners than non-depressed pregnant women (36.4 vs 72.2%, P<0.05; Fisher exact test). Black women predominated among pre- and postnatally depressed subjects. Postnatal depression was associated with lower parity (0.4 ± 0.5 vs 1.1 ± 1.0, P<0.05; Student t-test). Thus, the period of pregnancy may be susceptible to socio-environmental factors that induce depression, such as the lack of affective support from the partner. The prevalence rate of 12% observed for depression in the third month postpartum is comparable to that of studies from other countries.

Food, mood and health: a neurobiologic outlook

Hippocrates was the first to suggest the healing power of food; however, it was not until the medieval ages that food was considered a tool to modify temperament and mood, although scientific methods as we know them today were not in use at the time. Modern scientific methods in neuroscience began to emerge much later, leading investigators to examine the role of diet in health, including mental well-being, with greater precision. This review shows how short- and long-term forced dietary interventions bring about changes in brain structure, chemistry, and physiology, leading to altered animal behavior. Examples will be presented to show how diets alter brain chemistry, behavior, and the action of neuroactive drugs. Most humans and most animal species examined in a controlled setting exhibit a fairly reproducible pattern of what and how they eat. Recent data suggest that these patterns may be under the neurochemical and hormonal control of the organisms themselves. Other data show that in many instances food may be used unconsciously to regulate mood by seemingly normal subjects as well as those undergoing drug withdrawal or experiencing seasonal affective disorders and obesity-related social withdrawal. We will discuss specific examples that illustrate that manipulation of dietary preference is actually an attempt to correct neurochemical make-up.

The study of genetic polymorphisms related to serotonin in Alzheimer's disease: a new perspective in a heterogenic disorder

Genetic and environmental factors have been implicated in the development of Alzheimer's disease (AD), the most common form of dementia in the elderly. Mutations in 3 genes mapped on chromosomes 21, 14 and 1 are related to the rare early onset forms of AD while the e4 allele of the apolipoprotein E (APOE) gene (on chromosome 19) is the major susceptibility locus for the most common late onset AD (LOAD). Serotonin (5-hydroxytryptamine or 5-HT) is a key neurotransmitter implicated in the control of mood, sleep, appetite and a variety of traits and behaviors. Recently, a polymorphism in the transcriptional control region upstream of the 5-HT transporter (5-HTT) gene has been studied in several psychiatric diseases and personality traits. It has been demonstrated that the short variant(s) of this 5-HTT gene-linked polymorphic region (5-HTTLPR) is associated with a different transcriptional efficiency of the 5-HTT gene promoter resulting in decreased 5-HTT expression and 5-HT uptake in lymphocytes. An increased frequency of this 5-HTTLPR short variant polymorphism in LOAD was recently reported. In addition, another common polymorphic variation in the 5-HT2A and 5-HT2C serotonin receptor genes previously analyzed in schizophrenic patients was associated with auditory and visual hallucinations in AD. These observations suggest that the involvement of the serotonin pathway might provide an explanation for some aspects of the affective symptoms commonly observed in AD patients. In summary, research on genetic polymorphisms related to AD and involved in receptors, transporter proteins and the enzymatic machinery of serotonin might enhance our understanding of this devastating neurodegenerative disorder.

Johtamisen, kommunikaation ja organisaation oikeudenmukaisuuden vaikutus sitoutumiseen ICT-alan organisaatiossa ja sitouttamisen keinot

Organisaatioon sitoutuminen on organisaation kannalta kriittinen ilmiö. Sen nähdään vähentävän henkilöstön vaihtuvuutta ja aineettoman pääoman katoa organisaatiosta. Tässä työssä tutkittiin erään valtionhallinnon laitoksen henkilöstön organisaatioon sitoutumisen tasoa ja siihen vaikuttavia tekijöitä. Tutkimuksessa organisaatioon sitoutumista tarkasteltiin johtamisen, kommunikaation ja organisaation oikeudenmukaisuuden näkökulmasta. Kaikkia tutkittavia tekijöitä tarkasteltiin sekä globaalista, että lokaalista näkökulmasta. Tutkimuksessa havaittiin ainoastaan globaalin tason vaikuttajilla olevan merkittävä vaikutus organisaatioon sitoutumisessa, ainoana poikkeuksena lokaali oikeudenmukaisuus. Organisaatioon sitoutumisen havaittiin perustuvan sitoutumisen tunneperäiseen elementtiin, velvollisuudentunnon ja jatkuvuusperäisen komponentin jäädessä heikommiksi. Merkittävä havainto oli tutkimuksissa havaittujen demografisten vaikuttajien korreloivan joko ainoastaan heikosti tai ei lainkaan organisaatioon sitoutumiseen. Tutkimuksessa tarkasteltiin myös kriittisten asiantuntijoiden ja perusasiantuntijoiden sitoutumisen eroja. Kriittisten asiantuntijoiden havaittiin olevan heikommin sitoutuneita ja sitoutumisen tekijöiden globaalin tason vaikutuksen olevan merkittävästi vahvempi heihin, kuin perusasiantuntijoihin. Perusasiantuntijoiden havaittiin kiinnittyvän lokaaleihin tekijöihin, joilla on heikompi, tai ei juurikaan vaikutusta organisaatioon sitoutumiseen. Vaikuttavimmiksi organisaatioon sitoutumista vahvistaviksi tekijöiksi tunnistettiin johtamisen ja kommunikaation laadukkuus, ja organisaation osoittama oikeudenmukaisuus.

Diagnostic profile of inpatients as a determinant of length of stay in a general hospital psychiatric unit

The aim of this study was to determine if the diagnostic profile of inpatients of a psychiatric unit in a general hospital influences the length of stay. The results of a retrospective survey comprising the first 16 years of operation of the Psychiatric Unit of the Ribeirão Preto General Hospital (PURP) showed that the progressive increase observed in the length of stay correlated with the increase in percentage of schizophrenia diagnosis, after the 8th year of hospital operation, and of affective disorders, after the 12th year. The length of hospitalization kept increasing until the 16th year, even though there was no change in the diagnostic profile of the patients admitted to the unit. In a prospective study encompassing the next six months, 61 inpatients were evaluated with the Structured Clinical Interview for DSM-III-R and the Brief Psychiatric Rating Scale (BPRS). The results showed that 82% of the inpatients fulfilled the diagnostic criteria for the schizophrenic or affective disorder spectrum at admission, with a discharge rate slower than for other diagnoses, although the length of hospitalization did not significantly differ among diagnostic categories. The results further demonstrated that in every diagnostic category more than 50% of the patients stayed in hospital for more than one week after reaching a BPRS score equal to 6, indicative of discharge. Overall, these data suggest that the increase in length of hospitalization may be due to a higher percentage of patients with a diagnosis of schizophrenia and affective disorder admitted to the PURP. In addition, patients with low symptomatic levels remained in hospital longer than they should have.

Behavioral modulation by mutilation pictures in women

Previous studies have shown that women are more emotionally expressive than men. It is unclear, however, if women are also more susceptible to the emotional modulation of behavior imposed by an affective stimulus. To investigate this issue, we devised a task in which female subjects performed six sequential trials of visual target detection following the presentation of emotional (mutilation and erotic) or neutral pictures (domestic utensils and objects) and compared the data obtained in the present study with those described in a previous study with male subjects. The experiment consisted of three blocks of 24 pictures and each block had an approximate duration of 4 min. Our sample consisted of 36 subjects (age range: 18 to 26 years) and each subject performed all blocks. Trials following the presentation of mutilation pictures (283 ms) had significantly slower reaction times than those following neutral (270 ms) pictures. None of the trials in the "pleasant block" (271 ms) was significantly different from those in the "neutral block". The increase in reaction time observed in the unpleasant block may be related in part to the activation of motivational systems leading to an avoidance behavior. The interference effect observed in this study was similar to the pattern previously described for men. Thus, although women may be more emotionally expressive, they were not more reactive to aversive stimuli than men, as measured by emotional interference in a simple reaction time task.

Preliminary data on the prevalence of psychiatric disorders in Brazilian male and female juvenile delinquents

The aim of the present investigation was to study the prevalence of psychiatric disorders in a sample of delinquent adolescents of both genders and to compare the prevalence between genders. A total of 116 adolescents (99 males and 17 females) aged 12 to 19 on parole in the State of Rio de Janeiro were interviewed using the screening interview based on the Schedule for Affective Disorders and Schizophrenia for School-Age Children - Present and Lifetime (KSADS-PL). Data were collected between May 2002 and January 2003. Of 373 male and 58 female adolescents present in May 2002 in the largest institution that gives assistance to adolescents on parole in the city of Rio de Janeiro, 119 subjects were assessed (three of them refused to participate). Their average age was 16.5 years with no difference between genders. The screening interview was positive for psychopathology for most of the sample, with the frequencies of the suggested more prevalent psychiatric disorders being 54% for attention-deficit/hyperactivity disorder, 77% for conduct disorder, 41% for oppositional defiant disorder, 57% for anxiety disorder 57, 60% for depressive disorder 60, 63% for illicit drug abuse, and 58% for regular alcohol use. Internalizing disorders (depressive disorders, anxiety disorders and phobias) were more prevalent in the female subsample. There was no significant difference in the prevalence of illicit drug abuse between genders. There were more male than female adolescents on parole and failure to comply with the sentence was significantly more frequent in females. The high prevalence of psychopathology suggested by this study indicates the need for psychiatric treatment as part of the prevention of juvenile delinquency or as part of the sentence. However, treatment had never been available for 93% of the sample in this study.

The mental health of graduate students at the Federal University of São Paulo: a preliminary report

We present data regarding the care provided to graduate level health professionals at the mental health center of the Federal University of São Paulo. From September 1996 to September 2003, 146 graduate students (99 in the Master's degree program and 47 in the Doctoral program) were attended. This population was predominantly female (68.5%), with a mean (± SD) age of 28.6 ± 4.42 years, not married (71.9%). Most of the subjects were professionals who had not graduated from the Federal University (78.1%). The students who sought help for psychological and/or psychiatric problems were classified into two categories: situational-adaptive crises and psychopathological crises. The main diagnoses were depression and anxiety disorders (44%) causing 4.5% of the subjects to be temporarily suspended from their graduate studies; 19.2% reported that they had used psychotropic drugs within the previous month, and 47.9% referred to sleep disturbances. Suicidal tendencies were mentioned by 18% of those interviewed. Students with emotional disturbances and academic dysfunctions should be recognized at an early stage, and it is fundamental for them to have access to mental health programs that provide formal, structured and confidential care. Thus, it is important that professors and advisors in graduate programs build a warm and affective learning environment. If we consider the expressive growth in Brazilian scientific production resulting from the implementation of an extensive national system of graduate education, it is important to focus efforts on enhancing and upgrading the mental health care system.

The reliability of the Brazilian version of the Composite International Diagnostic Interview (CIDI 2.1)

The objective of the present study was to determine the reliability of the Brazilian version of the Composite International Diagnostic Interview 2.1 (CIDI 2.1) in clinical psychiatry. The CIDI 2.1 was translated into Portuguese using WHO guidelines and reliability was studied using the inter-rater reliability method. The study sample consisted of 186 subjects from psychiatric hospitals and clinics, primary care centers and community services. The interviewers consisted of a group of 13 lay and three non-lay interviewers submitted to the CIDI training. The average interview time was 2 h and 30 min. General reliability ranged from kappa 0.50 to 1. For lifetime diagnoses the reliability ranged from kappa 0.77 (Bipolar Affective Disorder) to 1 (Substance-Related Disorder, Alcohol-Related Disorder, Eating Disorders). Previous year reliability ranged from kappa 0.66 (Obsessive-Compulsive Disorder) to 1 (Dissociative Disorders, Maniac Disorders, Eating Disorders). The poorest reliability rate was found for Mild Depressive Episode (kappa = 0.50) during the previous year. Training proved to be a fundamental factor for maintaining good reliability. Technical knowledge of the questionnaire compensated for the lack of psychiatric knowledge of the lay personnel. Inter-rater reliability was good to excellent for persons in psychiatric practice.

Validation of the Beck Depression Inventory for a Portuguese-speaking Chinese community in Brazil

The objective of the present study was to investigate the psychometric properties and cross-cultural validity of the Beck Depression Inventory (BDI) among ethnic Chinese living in the city of São Paulo, Brazil. The study was conducted on 208 community individuals. Reliability and discriminant analysis were used to test the psychometric properties and validity of the BDI. Principal component analysis was performed to assess the BDI's factor structure for the total sample and by gender. The mean BDI score was lower (6.74, SD = 5.98) than observed in Western counterparts and showed no gender difference, good internal consistency (Cronbach's alpha 0.82), and high discrimination of depressive symptoms (75-100%). Factor analysis extracted two factors for the total sample and each gender: cognitive-affective dimension and somatic dimension. We conclude that depressive symptoms can be reliably assessed by the BDI in the Brazilian Chinese population, with a validity comparable to that for international studies. Indeed, cultural and measurement biases might have influenced the response of Chinese subjects.

Engagement of multifocal neural circuits during recall of autobiographical happy events

Happy emotional states have not been extensively explored in functional magnetic resonance imaging studies using autobiographic recall paradigms. We investigated the brain circuitry engaged during induction of happiness by standardized script-driven autobiographical recall in 11 healthy subjects (6 males), aged 32.4 ± 7.2 years, without physical or psychiatric disorders, selected according to their ability to vividly recall personal experiences. Blood oxygen level-dependent (BOLD) changes were recorded during auditory presentation of personal scripts of happiness, neutral content and negative emotional content (irritability). The same uniform structure was used for the cueing narratives of both emotionally salient and neutral conditions, in order to decrease the variability of findings. In the happiness relative to the neutral condition, there was an increased BOLD signal in the left dorsal prefrontal cortex and anterior insula, thalamus bilaterally, left hypothalamus, left anterior cingulate gyrus, and midportions of the left middle temporal gyrus (P < 0.05, corrected for multiple comparisons). Relative to the irritability condition, the happiness condition showed increased activity in the left insula, thalamus and hypothalamus, and in anterior and midportions of the inferior and middle temporal gyri bilaterally (P < 0.05, corrected), varying in size between 13 and 64 voxels. Findings of happiness-related increased activity in prefrontal and subcortical regions extend the results of previous functional imaging studies of autobiographical recall. The BOLD signal changes identified reflect general aspects of emotional processing, emotional control, and the processing of sensory and bodily signals associated with internally generated feelings of happiness. These results reinforce the notion that happiness induction engages a wide network of brain regions.