Lack of seasonal variation in cardiovascular mortality in a country near the equator

Introduction: Mortality from cardiovascular disease (CVD) varies according to seasons in countries that are located far away from the equator, likely linked to concomitant seasonal variation in underlying CVD risk factors. We assessed temporal variation in CVD mortality in the Seychelles, a small island state situated near the equator and where the climate is virtually constant throughout the year. Seychelles is one of the few countries located near the equator where all deaths are registered. Methods: We recoded all deaths along broad causes, including CVD (n=5643), stroke (2112) and myocardial infarction (MI, 804). Stroke and MI were considered as the cause of death if the diagnosis appeared in any of the four fields for underlying causes of death in the death certificates. In view of the small size of the population, we pooled all deaths (n=13'163) between 1989 and 2010. Results: Mortality for all CVD, stroke and MI did not systematically vary according to month or season (chi square >0.05). A lack of variation was also observed within sex and age categories. Conclusion: The lack of seasonal variation in CVD mortality in a country located near the equator is consistent with the hypothesis that seasonal variation in CVD decreases along decreasing a country's latitude.

NR2A at CA1 synapses is obligatory for the susceptibility of hippocampal plasticity to sleep loss.

A loss in the necessary amount of sleep alters expression of genes and proteins implicated in brain plasticity, but key proteins that render neuronal circuits sensitive to sleep disturbance are unknown. We show that mild (4-6 h) sleep deprivation (SD) selectively augmented the number of NR2A subunits of NMDA receptors on postsynaptic densities of adult mouse CA1 synapses. The greater synaptic NR2A content facilitated induction of CA3-CA1 long-term depression in the theta frequency stimulation range and augmented the synaptic modification threshold. NR2A-knock-out mice maintained behavioral response to SD, including compensatory increase in post-deprivation resting time, but hippocampal synaptic plasticity was insensitive to sleep loss. After SD, the balance between synaptically activated and slowly recruited NMDA receptor pools during temporal summation was disrupted. Together, these results indicate that NR2A is obligatory for the consequences of sleep loss on hippocampal synaptic plasticity. These findings could advance pharmacological strategies aiming to sustain hippocampal function during sleep restriction.

Stratification of the severity of critically ill patients with classification trees

Background: Development of three classification trees (CT) based on the CART (Classification and Regression Trees), CHAID (Chi-Square Automatic Interaction Detection) and C4.5 methodologies for the calculation of probability of hospital mortality; the comparison of the results with the APACHE II, SAPS II and MPM II-24 scores, and with a model based on multiple logistic regression (LR). Methods: Retrospective study of 2864 patients. Random partition (70:30) into a Development Set (DS) n = 1808 and Validation Set (VS) n = 808. Their properties of discrimination are compared with the ROC curve (AUC CI 95%), Percent of correct classification (PCC CI 95%); and the calibration with the Calibration Curve and the Standardized Mortality Ratio (SMR CI 95%). Results: CTs are produced with a different selection of variables and decision rules: CART (5 variables and 8 decision rules), CHAID (7 variables and 15 rules) and C4.5 (6 variables and 10 rules). The common variables were: inotropic therapy, Glasgow, age, (A-a)O2 gradient and antecedent of chronic illness. In VS: all the models achieved acceptable discrimination with AUC above 0.7. CT: CART (0.75(0.71-0.81)), CHAID (0.76(0.72-0.79)) and C4.5 (0.76(0.73-0.80)). PCC: CART (72(69- 75)), CHAID (72(69-75)) and C4.5 (76(73-79)). Calibration (SMR) better in the CT: CART (1.04(0.95-1.31)), CHAID (1.06(0.97-1.15) and C4.5 (1.08(0.98-1.16)). Conclusion: With different methodologies of CTs, trees are generated with different selection of variables and decision rules. The CTs are easy to interpret, and they stratify the risk of hospital mortality. The CTs should be taken into account for the classification of the prognosis of critically ill patients.

Comparison between land suitability and actual crop distribution in an irrigation district of the Ebro valley (Spain)

El objetivo de la presente investigación fue analizar la correspondencia entre los resultados de una evaluación de tierras con la distribución real de los cultivos. Para ello la aptitud biofísica de las tierras se comparó con diferentes tipologías de frecuencia de ocurrencia de los cultivos y rotaciones derivadas de mapas de cultivos multitemporales. La investigación fue llevada a cabo en el distrito de riego de Flumen (33.000 ha), localizado en el valle del Ebro (NE España). La evaluación de tierras se basó en una cartografía de suelos 1:100.000, según el esquema FAO, para los principales cultivos presentes en el área de estudio (alfalfa, cereales de invierno, maíz, arroz y girasol). Se utilizaron tres mapas de frecuencia de cultivos y un mapa de rotaciones, derivado de una serie temporal de imágenes Landsat TM y ETM+ del periodo 1993-2000, y se compararon con los mapas de aptitud de tierras para los diferentes cultivos. Se analizó estadísticamente (Pearson χ2, Cramer V, Gamma y Somers D) la relación entre los dos tipos de variables. Los resultados muestran la existencia de una relación significativa (P=0,001) entre la localización de los cultivos y la idoneidad de las tierras, excepto de cultivos oportunistas como el girasol, muy influenciado por las subvenciones en el periodo estudiado. Las rotaciones basadas en la alfalfa muestran los mayores porcentajes (52%) de ocupación en las tierras más aptas para la agricultura en el área de estudio. El presente enfoque multitemporal de análisis de la información ofrece una visión más real que la comparación entre un mapa de evaluación de tierras y un mapa de cultivos de una fecha determinada, cuando se valora el grado de acuerdo entre las recomendaciones sobre la aptitud de las tierras y los cultivos realmente cultivados por los agricultores.

Correlation between the oropharyngo-laryngoscopic findings and the severity of obstructive sleep apnea

Objective: To correlate anatomical and functional changes of the oral cavity, pharynx and larynx to the severity of obstructive sleep apnea syndrome (OSAS). Methods : We conducted a cross-sectional study of 66 patients of both genders, aged between 21 and 59 years old with complaints of snoring and / or apnea. All underwent full clinical evaluation, including physical examination, nasolarybgoscopy and polisonography. We classified individuals into groups by the value of the apnea-hypopnea index (AHI), calculated measures of association and analyzed differences by the Kruskal-Wallis and chi-square tests. Results : all patients with obesity type 2 had OSAS. We found a relationship between the uvula projection during nasoendoscopy and OSAS (OR: 4.9; p-value: 0.008; CI: 1.25-22.9). In addition, there was a major strength of association between the circular shape of the pharynx and the presence of moderate or severe OSAS (OR: 9.4, p-value: 0.002), although the CI was wide (1.80-53.13). The septal deviation and lower turbinate hypertrophy were the most frequent nasal alterations, however unrelated to gravity. Nasal obstruction was four times more common in patients without daytime sleepiness. The other craniofacial anatomical changes were not predictors for the occurrence of OSAS. Conclusion : oral, pharyngeal and laryngeal disorders participate in the pathophysiology of OSAS. The completion of the endoscopic examination is of great value to the evaluation of these patients.

The role of P16ink4a and P53 immunostaining in predicting recurrence of HG-CIN after conization treatment

Objective: Io evaluate the expression of p16INK4a and p53 biomarkers in conization specimens from patients with high grade cervical intraepithelial neoplasia (HG-CIN), correlating them with the ability to predict the recurrence. Methods : we conducted a retrospective study of patients with HG-CIN in cervical biopsy treated with conization between January 1999 and January 2006 who had a minimum follow-up of 18 months. The expression of the p16 and p53 was assessed by tissue microarrays and correlated with disease recurrence. For analysis, we used the test of proportions (chi-square), considering value p<0.05, 95% CI and calculations of sensitivity, specificity and accuracy of these immunomarkers in predicting recurrence. Results : the series comprised 83 patients aged between 16 and 86 years (35±11.7), divided into two groups: 30 with HG-CIN recurrence (study group) and 53 without recurrence (control group). Mean age, parity, smoking and conization technique were similar in both groups. The p53 expression was present in 43% of the study group and 57% of the control group, and the p16 was present in 43% of the study group and in 57% of the control group (p>0.05). p53 had a positive predictive value (PPV) of 42% and negative predictive value (NPV) of 73%, sensitivity 70%, specificity of 47% and accuracy of 59%. The p16, PPV 42%, NPV 72%, sensitivity 66%, specificity of 49% and accuracy of 56%. Conclusion : immunohistochemistry expression of p53 and p16 showed low sensitivity and low specificity as predictors of HG-CIN recurrence after conization treatment.

Fibrinonecrotic enteritis of piglets in a commercial farm: a postmortem study of the prevalence and the role of lesion associated agents Isospora suis and Clostridium perfringens

The objectives were to determine the prevalence of fibrinonecrotic enteritis (FNE) on a farrow-to-finish farm of 1,000 sows, to categorize the pathological changes, and to to investigate the lesion associated agents Isospora suis and Clostridium perfringens. Causes of preweaning mortality (PWM) were classified into 8 categories including FNE. Obtained data were evaluated for statistical significance by adjusted Chi-square analysis. Samples of FNE were taken for complementary studies including a PCR technique for genotyping toxin genes of Clostridium perfringens from gut samples fixed in 10% neutral formalin. From 3,153 piglets examined, less than 1% was classified as FNE. FNE prevalence increased progressively from the first to the third week, the last differing statistically from the others. Eighty percent of gut samples with FNE lesions were positive to Isospora suis, when examined by PCR from 9 severe FNE lesions detected 7 positive samples only for a toxin gene, characteristic of C. perfringens type-A.

Neuroethologic differences in sleep deprivation induced by the single- and multiple-platform methods

It has been proposed that the multiple-platform method (MP) for desynchronized sleep (DS) deprivation eliminates the stress induced by social isolation and by the restriction of locomotion in the single-platform (SP) method. MP, however, induces a higher increase in plasma corticosterone and ACTH levels than SP. Since deprivation is of heuristic value to identify the functional role of this state of sleep, the objective of the present study was to determine the behavioral differences exhibited by rats during sleep deprivation induced by these two methods. All behavioral patterns exhibited by a group of 7 albino male Wistar rats submitted to 4 days of sleep deprivation by the MP method (15 platforms, spaced 150 mm apart) and by 7 other rats submitted to sleep deprivation by the SP method were recorded in order to elaborate an ethogram. The behavioral patterns were quantitated in 10 replications by naive observers using other groups of 7 rats each submitted to the same deprivation schedule. Each quantification session lasted 35 min and the behavioral patterns presented by each rat over a period of 5 min were counted. The results obtained were: a) rats submitted to the MP method changed platforms at a mean rate of 2.62 ± 1.17 platforms h-1 animal-1; b) the number of episodes of noninteractive waking patterns for the MP animals was significantly higher than that for SP animals (1077 vs 768); c) additional episodes of waking patterns (26.9 ± 18.9 episodes/session) were promoted by social interaction in MP animals; d) the cumulative number of sleep episodes observed in the MP test (311) was significantly lower (chi-square test, 1 d.f., P<0.05) than that observed in the SP test (534); e) rats submitted to the MP test did not show the well-known increase in ambulatory activity observed after the end of the SP test; f) comparison of 6 MP and 6 SP rats showed a significantly shorter latency to the onset of DS in MP rats (7.8 ± 4.3 and 29.0 ± 25.0 min, respectively; Student t-test, P<0.05). We conclude that the social interaction occurring in the MP test generates additional stress since it increases the time of forced wakefulness and reduces the time of rest promoted by synchronized sleep.

Defense reaction induced by a metabotropic glutamate receptor agonist microinjected into the dorsal periaqueductal gray of rats

The behavioral effects of trans-(±)-1-amino-1,3-cyclopentanedicarboxylic acid (t-ACPD), a metabotropic glutamate receptor (mGluR) agonist, or 0.9% (w/v) saline, injected into the dorsal periaqueductal gray (DPAG), was investigated. Male Wistar rats showed defense reactions characterized by jumps toward the top edges of the cages (saline = 0 vs t-ACPD = 6.0, medians P<0.05) and gallops (saline = 0 vs t-ACPD = 10.0, medians P<0.05) during the 60-s period after the beginning of the injection. In another experiment animals were placed inside an open arena for 5 min immediately after injection. Their behavior was recorded by a video camera and a computer program analyzed the videotapes. Eleven of fifteen rats injected with t-ACPD showed a short-lasting (about 1 min) flight reaction. No saline-treated animal showed this reaction (P<0.0005, chi-square test). The drug induced an increase in turning behavior (P = 0.002, MANOVA) and a decrease in the number of rearings (P<0.001, MANOVA) and grooming episodes (P<0.001, MANOVA). These results suggest that mGluRs play a role in the control of defense reactions in the DPAG.

Social class as a factor for the construction of a musician’s identity : The Musician’s social background and identity questionnaire (MSBIQ) – a cross-sectional comparative quantitative online survey research study of music students at two higher education institutions in Finland

There is currently little empirical knowledge regarding the construction of a musician’s identity and social class. With a theoretical framework based on Bourdieu’s (1984) distinction theory, Bronfenbrenner’s (1979) theory of ecological systems, and the identity theories of Erikson (1950; 1968) and Marcia (1966), a survey called the Musician’s Social Background and Identity Questionnaire (MSBIQ) is developed to test three research hypotheses related to the construction of a musician’s identity, social class and ecological systems of development. The MSBIQ is administered to the music students at Sibelius Academy of the University of Arts Helsinki and Helsinki Metropolia University of Applied Sciences, representing the ’highbrow’ and the ’middlebrow’ samples in the field of music education in Finland. Acquired responses (N = 253) are analyzed and compared with quantitative methods including Pearson’s chi-square test, factor analysis and an adjusted analysis of variance (ANOVA). The study revealed that (1) the music students at Sibelius Academy and Metropolia construct their subjective musician’s identity differently, but (2) social class does not affect this identity construction process significantly. In turn, (3) the ecological systems of development, especially the individual’s residential location, do significantly affect the construction of a musician’s identity, as well as the age at which one starts to play one’s first musical instrument. Furthermore, a novel finding related to the structure of a musician’s identity was the tripartite model of musical identity consisting of the three dimensions of a musician’s identity: (I) ’the subjective dimension of a musician’s identity’, (II) ’the occupational dimension of a musician’s identity’ and, (III) ’the conservative-liberal dimension of a musician’s identity’. According to this finding, a musician’s identity is not a uniform, coherent entity, but a structure consisting of different elements continuously working in parallel within different dimensions. The results and limitations related to the study are discussed, as well as the objectives related to future studies using the MSBIQ to research the identity construction and social backgrounds of a musician or other performing artists.

Association of the 894G>T polymorphism of the endothelial constitutive nitric oxide synthase gene with unstable angina

The 894G>T polymorphism of the endothelial constitutive nitric oxide synthase gene consists of the substitution of a guanine base by a thymine at the 894th nucleotide of the gene. An association of this polymorphism with acute coronary syndromes has been described, only when in combination with other polymorphisms of this gene. The aim of the present study was to search for an association between this polymorphism and unstable angina in a southern Brazilian population. In a case-control study, 156 patients (group 1 (N = 83): unstable angina, group 2 (N = 73): stable angina) were genotyped by PCR and digestion of the product. Univariate analysis demonstrated that the minimal luminal diameter and the degree of stenosis of the culprit lesion differed between groups (P = 0.006 and 0.005, respectively). In addition, the frequencies of the T allele and of the T allele carriers (combined TT and TG genotypes) were significantly higher in the group with unstable angina (41.6 vs 28.8%; P = 0.025, Pearson chi-square test, and 73.5 vs 45.2%; P = 0.001, Pearson chi-square test, respectively). Multivariate logistic regression showed that the frequency of the T allele carriers was the only variable with a predictive value for unstable angina, when controlled for the other variables (6.1 (95% CI = 2.55-14.43); P < 0.001). Thus, in a homogenous group of patients, the endothelial constitutive nitric oxide synthase 894G>T polymorphism was associated with unstable angina. We suggest that this polymorphism may be a genetic risk factor for unstable angina.

High levels of serum mannose-binding lectin are associated with the severity of clinical signs of leptospirosis

The clinical heterogeneity observed in leptospirosis may be associated with host factors or bacteria virulence. Human serum mannose-binding lectin (MBL) recognizes many pathogens, and low levels of this lectin are associated with susceptibility to infection. MBL is also implicated in the modulation of the inflammatory process. We determined the levels of serum MBL during leptospirosis infection. A double-antibody sandwich ELISA was used to detect the immunoreactive serum MBL. The ELISA plates were coated with monoclonal antibody to MBL and bound MBL or recombinant human MBL were detected by rabbit anti-human MBL serum. HRPO-conjugated goat anti-rabbit antibody was used for detection of the reaction. Two groups of patients seen at referral hospitals in Recife, PE, Brazil, were divided according to the year of infection, 2001 (N = 61) or 2002 (N = 57) and compared in terms of disease severity and levels of serum MBL. A group of healthy volunteers (N = 97) matched by age, gender, and ethnic background was used as control. Patients infected in 2001 had more severe outcomes than those infected in 2002, including jaundice, hemorrhage, respiratory alteration, and renal complication (P = 0.0009; chi-square test). The frequency of patients producing serum MBL >1000 ng/mL was higher in the 2001 group than in the 2002 and control groups (P < 0.01), suggesting an association of MBL level with disease severity. The involvement of MBL and genetic variation of the MBL2 gene should be further evaluated to establish the role of this lectin in the pathogenesis of leptospirosis.

Adolescent sexuality : an investigation into the relation between sexuality and self-concept /

The present study explored the connections among adolescents' sense of self, sexuality, and perceptions of risk. Such an exploration may help educators to further understand why adolescents engage in risk-taking behaviours such as unprotected sex. The study involved secondary analysis on the data collected from the Youth Lifestyle Choices - Community University Research Alliance 2000 (YLC - CURA) Youth Resilience Questionnaire (YRQ). Participants were 300 male and female students in Grades 9, 1 1 and OAC. Data analyses involved both descriptive and inferential statistics (correlational and multivariate analysis). Chi-square analyses were performed on the open-ended self-description question. Separate analyses were conducted on gender and age (grade levels). Correlational analyses revealed that adolescents with a more positive sense of self were more likely to perceive sexual involvement as a relatively high-risk behaviour. Specifically, results found that male adolescents were less likely than females to perceive sex to be risky. Results are discussed in relation to previous research in the area of selfcognitions and risk-taking sexual behaviour. Results are also discussed in terms of educational implications in that the current results may provide the beginnings of a framework for more holistic sexual education programs.

Applying andragogy to the open college learner

Questionnaires were sent to 703 Open College students. The questionnaire asked questions regarding personal demographics, how they felt about andragogy as postulated by Malcolm Knowles, and invited responses pertaining to the institutional practices of Open College. Two hundred and ninety-four responses were received. The information was synthesized and used descriptively. The information regarding andragogy was also used descriptively and analyzed using chi-square. The statistics were compared by gender. No significant difference was found. Students rejected the concept of self-directed learning. They did use their past experience when preparing assignments, however. They also entered Open College in order to learn how to do something better rather than for esoteric reasons. In fact, their whole orientation to learning was very practical in nature. The factors motivating these learners were internal rather than external. In addition, institutional practices were identified that could further enhance the Open College experience.