Survival analysis: a tool in the study of post-harvest diseases in peaches

Survival analysis is applied when the time until the occurrence of an event is of interest. Such data are routinely collected in plant diseases, although applications of the method are uncommon. The objective of this study was to use two studies on post-harvest diseases of peaches, considering two harvests together and the existence of random effect shared by fruits of a same tree, in order to describe the main techniques in survival analysis. The nonparametric Kaplan-Meier method, the log-rank test and the semi-parametric Cox's proportional hazards model were used to estimate the effect of cultivars and the number of days after full bloom on the survival to the brown rot symptom and the instantaneous risk of expressing it in two consecutive harvests. The joint analysis with baseline effect, varying between harvests, and the confirmation of the tree effect as a grouping factor with random effect were appropriate to interpret the phenomenon (disease) evaluated and can be important tools to replace or complement the conventional analysis, respecting the nature of the variable and the phenomenon.

Genetic Jacobinism in the republic of choice

Revista de Filosofia da Unidade de Investigação em Ciência, Tecnologia e Sociedade da Universidade Lusófona

Health knowledge of prostitutes in Saigon, Vietnam: a study of health attitudes and habits relating to venereal diseases taken from a group of prostitutes

A study of health knowledge and practices of prostitutes is presented here. The study took place at the V. D. Center in Saigon, Vietnam. It was designed with the objective of obtaining information to be used in preparing an educational program to be offered to the prostitutes at the Center, and for using, in preparing educational materials with focus on V. D. prevention. The outline of a course is also presented.

Agricultural development and arthropod-borne diseases: a review

A review is presented of the interrelationships between arthropod vectors, the diseases they transmit and agricultural development. Particular attention is given to the effects of deforestation, livestock development and irrigation on the abundance of vectors and changing patterns of diseases such as malaria, trypanosomiases, leishmaniasis, Chagas' and some arboviral infections. The question as whether keeping livestock diverts biting away from people and reduces diseases such as malaria - that is zooprophylaxis, or whether the presence of cattle actually increases biting populations is discussed.

Assessment of a strategy for the control of respiratory diseases in children

A programme for the control of respiratory diseases in children was conceived for the State of S. Paulo, Brazil, in 1986. Its progress thereafter and the epidemiology of the diseases concerned are examined. Apart from an inquiry into the 64 existing State local health authorities, a sample of 18,255 cases of children assisted by the programme at different levels, including both in-patient and outpatient care, is analysed. Each case record included information about identification (child, doctor and health facility), reasons for calling, diagnoses made and outcome of treatment. Further data were also sought from hospitals and from State mortality records. The programme was found to be poorly implemented in the State but, where implemented, it showed itself capable of resolving problems (only 0.5% of the cases could not be handled) as also of changing ongoing trends (more than 50% reduction in hospital admission rates). Individual assessment of each item of the programme indicated its bottlenecks. Regarding the epidemiology of respiratory diseases, it is observed that the major burden to health services comes from children aged less than five, and that the most important diseases are wheezing illnesses and pneumonia. Morevoer, they were found to be significantly associated (p = 0.000) so that a child in the community presenting wheezing diseases is 5 times more likely to develop pneumonia than a child with any other respiratory diagnosis. Similarly, among the under five deaths it was found that the risk for pneumonia is 3 times greater for children who died presenting wheezing diseases than it is for children with any other sort of diagnosis. In conclusion, the programme is deemed to be efficient and effective but its efficacy is marred by administrative flaws. The successful control of respiratory problems in childhood is related to a proper appreciation of the importance of wheezing diseases.

Smoking, consumption of alcohol and sedentary life style in population grouping and their relationships with lipemic disorders

The study, part of the project "Atherosclerotic cardiovascular diseases, lipemic disorders, hypertension, obesity and diabetis mellitus in a population of the metropolitan area of the southeastern region of Brazil", had the following objectives: a) the characterization and distribution among typical human socio-economic groupings, of the prevalence of some particular habits which constitute aspects of life-style-the use of tobacco, the use of alcohol and sedentary activity; b) the establishment of the interrelation between the above-mentioned habits and some lipemic disorders. The prevalence of the habits cited behaved in the following manner: the use of tobacco predominated among men, distributed uniformly throughout the social strata; among the women the average percentage of smokers was 18,9%, a significant difference occurring among the highest socio-economic class, where the average was of 40.2%. The sedentary style of life presented high prevalence, among both men and women with exception of the women of the highest socio-economic level and of the skilled working class. The use of alcohol, as one would expect, is a habit basically practised by the men, without any statistically significant differences between classes. For the purpose of establishing associations between these risk fictors and lipemic conditions four situations were chosen, of the following characteristics: 1- total cholesterol > or = 220 mg/dl and triglycerides > or = 150 mg/dl; 2- HDL cholesterol <35 mg/dl for men and <45 mg/dl for women and triglycerides levels > or = 150 mg/dl; 3- HDL cholesterol <35 mg/dl for men and <45 mg/dl for women and triglycerides levels <150 mg/dl; 4- total cholesterol 220 mg/dl with triglycerides levels <150 mg/dl. Six models of multiple (backward) regression were established, with seven independent variables- age, sex, use of tobacco, consumption of alcohol, light physical activity, hypertension and obesity. Significant associations (P<0,05) were revealed with hypercholesterolemia, accompanied by triglyceride levels > or = 150 mg/dl, and the following independent variables: age, use of tobacco and the interactions between obesity and smoking, age and sedentary lifestyle, sex and obesity (R2=22%); the standardized B coefficient showed that the variables with the greatest weight in the forecasting of the variation in the levels of cholesterol were smoking and the interaction between obesity and smoking. The hypercholesterolemia accompanied by triglycerides levels <150 mg/dl showed a positive association between total cholesterol and sex and the interactions obesity/smoking and sex/obesity. As regards HDL cholesterol accompanied by triglyceride/ levels > or = 150 mg/dl was inversely associated with obesity and the interaction smoking/ age and directly with age (R=31%). The standardized B coeffients, indicated that the variables obesity and the interactions smoking/age possessed a weight three times greater than age alone in accounting for the variation in the serum levels of HDL cholesterol. When accompanied by triglycerides <150 mg/dl there was no association between and the independent variables and the set of them presented R equal to 22%. The sum of top, in the population stutied in this project, the component habits of life-style (smoking, alcohol consumption and sedentary activity) which constitute risk factors which determine morbidity from atherosclerotic cardiovascular diseases are be found distributed through all the typical social groupings of this particular form of social organization. On the other hand, the seven independent variables used in the multiple regression models for the explanation of the lipemic conditions considered presented multiple determination coefficients which varied, approximately, between 20% and 30%. Thus it is important that in the genetic epidemiology the study of the morbidities in question be emphasized.

Cost of diseases in Brazil: breast cancer, enteritis, cardiac valve disease and bronchopneumonia

The results from the need to develop methodologies for performing cost analysis in developing countries, principally in the region of Latin America, were studied. It, furthermore, serves to generate knowledge from an economic evaluation in order to support decision-making related to the organization of health systems, particularly in the efficient use of resources which are allocated for the provision of medical services. Two chronic diseases (breast cancer and cardiac valve disease) and two infections (enteritis and bronchopneumonia) were selected for the study. The results recommend the use of a valid methodology for economic cost analysis of any disease to be studied and the use of this information in the decision-making process.

Effects of physical exercise training in DNA damage and repair - could the difference be in hOGG1 Ser326Cys polymorphism?

Acute physical exercise is associated with increased oxygen consumption, which could result in an increased formation of reactive oxygen species (ROS). ROS can react with several organic structures, namely DNA, causing strand breaks and a variety of modified bases in DNA. Physical exercise training seems to decrease the incidence of oxidative stress-associated diseases, and is considered as a key component of a healthy lifestyle. This is a result of exercise-induced adaptation, which has been associated with the possible increase in antioxidant activity and in oxidative damage repair enzymes, leading to an improved physiological function and enhanced resistance to oxidative stress (Radak et al. 2008). Human 8-oxoguanine DNA glycosylase 1 (hOGG1) is involved in the base excision repair (BER) pathway and encodes an enzyme responsible for removing the most common product of oxidative damage in DNA, 8-hydroxyguanine (8-OH-G). The genetic polymorphism of hOGG1 at codon 326 results in a serine (Ser) to cysteine (Cys) amino acid substitution (Ser326Cys). It has been suggested that the carriers of at least one hOGG1Cys variant allele exhibit lower 8-OH-G excision activity than the wild-type (Wilson et al. 2011). The aim of this study was to investigate the possible influence of hOGG1 Ser326Cys polymorphism on DNA damage and repair activity in response to 16 weeks of combined physical exercise training, in thirty healthy Caucasian men. Comet assay was carried out using peripheral blood lymphocytes and enabled the evaluation of DNA damage, both strand breaks and FPG-sensitive sites, and DNA repair activity. Genotypes were determined by PCR-RFLP analysis. The subjects with Ser/Ser genotype were considered as wild-type group (n=20), Ser/Cys and Cys/Cys genotype were analyzed together as mutant group (n=10). Regarding differences between pre and post-training in the wild-type group, the results showed a significant decrease in DNA strand breaks (DNA SBs) (p=0.002) and also in FPG-sensitive sites (p=0.017). No significant differences were observed in weight (p=0.389) and in lipid peroxidation (MDA) (p=0.102). A significant increase in total antioxidant capacity (evaluated by ABTS) was observed (p=0.010). Regarding mutant group, the results showed a significant decrease in DNA SBs (p=0.008) and in weight (p=0.028). No significant differences were observed in FPG-sensitive sites (p=0.916), in ABTS (p=0.074) and in MDA (p=0.086). No significant changes in DNA repair activity were observed in both genotype groups. This preliminary study suggests the possibility of different responses in DNA damage to physical exercise training, considering the hOGG1 Ser326Cys polymorphism.

Seasonal variation of total particulate matter and children respiratory diseases at Lisbon primary schools using passive methods

In this work, 14 primary schools of Lisbon city, Portugal, followed a questionnaire of the ISAAC - International Study of Asthma and Allergies in Childhood Program, in 2009/2010. The questionnaire contained questions to identify children with respiratory diseases (wheeze, asthma and rhinitis). Total particulate matter (TPM) was passively collected inside two classrooms of each of 14 primary schools. Two types of filter matrices were used to collect TPM: Millipore (IsoporeTM) polycarbonate and quartz. Three campaigns were selected for the measurement of TPM: Spring, Autumn and Winter. The highest difference between the two types of filters is that the mass of collected particles was higher in quartz filters than in polycarbonate filters, even if their correlation is excellent. The highest TPM depositions occurred between October 2009 and March 2010, when related with rhinitis proportion. Rhinitis was found to be related to TPM when the data were grouped seasonally and averaged for all the schools. For the data of 2006/2007, the seasonal variation was found to be related to outdoor particle deposition (below 10 μm).

Environmental exposure to toxicants mixtures from a multi-purpose estuary: perspectives for a biomonitoring study in Portugal

This work was focused on a multi-purpose estuarine environment (river Sado estuary, SW Portugal) around which a number of activities (e.g., fishing, farming, heavy industry, tourism and recreational activities) coexist with urban centres with a total of about 200 000 inhabitants. Based on previous knowledge of the hazardous chemicals within the ecosystem and their potential toxicity to benthic species, this project intended to evaluate the impact of estuarine contaminants on the human and ecosystem health. An integrative methodology based on epidemiological, analytical and biological data and comprising several lines of evidence, namely, human contamination pathways, human health effects, consumption of local produce, estuarine sediments, wells and soils contamination, effects on commercial benthic organisms, and genotoxic potential of sediments, was used. The epidemiological survey confirmed the occurrence of direct and indirect (through food chain) exposure of the local population to estuarine contaminants. Furthermore, the complex mixture of contaminants (e.g., metals, pesticides, polycyclic aromatic hydrocarbons) trapped in the estuary sediments was toxic to human liver cells exposed in vitro, causing cell death, oxidative stress and genotoxic effects that might constitute a risk factor for the development of chronic-degenerative diseases, on the long term. Finally, the integration of data from several endpoints indicated that the estuary is moderately impacted by toxicants that affect also the aquatic biota. Nevertheless, the human health risk can only be correctly assessed through a biomonitoring study including the quantification of contaminants (or metabolites) in biological fluids as well as biomarkers of early biological effects (e.g., biochemical, genetic and omics-based endpoints) and genetic susceptibility in the target population. Data should be supported by a detailed survey to assess the impact of the contaminated seafood and local farm products consumption on human health and, particularly, on metabolic diseases or cancer development.

Vigilância de síndromes com anomalias congénitas que afetam múltiplos sistemas: dados do Registo Nacional de Anomalias Congénitas para os anos 2000 a 2013

O Registo Nacional de Anomalias Congénitas (RENAC) recebe notificações da ocorrência de anomalias congénitas diagnosticadas até ao final do 1º mês de vida, algumas das quais são raras. Foi realizado um estudo observacional, transversal, com a finalidade de descrever a epidemiologia dos registos de anomalias congénitas que constituem uma síndrome genética rara, utilizando os dados do RENAC entre 2000-2013. Observou-se uma prevalência de 1,17 casos/10 000 nascimentos de indivíduos com síndrome genética rara com anomalias que afetam múltiplos sistemas. Estas patologias representam um pequeno grupo do universo das doenças raras. No total das síndromes estudadas (n=171), a maior frequência observou-se no grupo de síndromes que afetam predominantemente o aspeto da face (50,9%) e, neste grupo, destacam-se a Sequência de Pierre Robin (26,3%) e a Síndrome de Goldenhar (11,7%). No grupo de outras síndromes genéticas, a Síndrome de DiGeorge foi diagnosticada em 12,3% dos casos. Dada a inexistência de um registo nacional de doenças raras, os dados do RENAC podem contribuir para avaliar a prevalência de algumas destas doenças. Contudo para uma melhor vigilância de algumas doenças raras, o prazo de registo será alargado até ao ano de idade de modo a permitir que situações mais complexas possam ser identificadas e registadas.

Doenças lisossomais de sobrecarga em Portugal: 10 anos de experiência em estudos moleculares no INSA (2006-2016)

As Doenças Lisososomais de Sobrecarga (DLS) são um grupo de mais de 50 doenças hereditárias do metabolismo, sendo a maioria causada por defeitos em enzimas lisossomais específicas. A característica distintiva das DLS é a acumulação lisossomal do(s) substrato(s) não degradado(s), bem como a acumulação de outro material secundariamente à disfunção lisossomal. A apresentação clínica destas patologias é bastante heterogénea, variando desde formas pré-natais, até apresentações infantis ou na idade adulta, sendo frequente a presença de atraso psicomotor e neurodegeneração progressiva. Neste artigo são apresentados os resultados de vários estudos de caracterização molecular efetuados ao longo da última década (2006-2016) em doentes portugueses com as seguintes DLS: Mucopolissacaridose II, Mucopolissacaridose IIIA, Mucopolissacaridose IIIB, Mucopolissacaridose IIIC, Sialidose, Galactosialidose, Gangliosidose GM1, Mucolipidose II alfa/beta, Mucolipidose III alfa/beta, Mucolipidose III gama e Doença de Unverricht-Lundborg. De um modo geral, estes trabalhos permitiram conhecer as variações genéticas associadas a estas DLS, analisar a sua distribuição na população portuguesa e compreender o seu papel na forma de apresentação clínica destas patologias.

Doenças mitocondriais: síndrome da depleção do mtDNA

As citopatias mitocondriais constituem um importante grupo de doenças metabólicas de expressão clínica heterogénea, para as quais não existe uma terapia eficaz. A maioria destas doenças é causada por uma disfunção ao nível da fosforilação oxidativa (OXPHOS), originando consequentemente uma deficiente produção de energia. O correto funcionamento da OXPHOS resulta de uma interação coordenada entre o genoma nuclear e mitocondrial. Assim, as doenças mitocondriais podem ser causadas por defeitos moleculares no genoma mitocondrial, no nuclear, ou em ambos, originando as doenças da comunicação intergenómica, que resultam na perda ou na instabilidade do DNA mitocondrial (mtDNA), e podem causar quer deleções múltiplas, quer depleção do genoma mitocondrial. A síndrome da depleção do mtDNA constitui um grupo de doenças raras, autossómicas recessivas, que se manifestam maioritariamente após o nascimento, causando a morte de muitos doentes durante a infância ou início da adolescência devido a uma redução acentuada do número de cópias do mtDNA. Trata-se de uma síndrome fenotipicamente heterogénea, apresentando-se sob três apresentações clínicas: hepatocerebral, miopática e encefalomiopática. A caracterização molecular destes doentes é importante não só para permitir a realização de aconselhamento genético e diagnóstico pré-natal adequados, mas também para melhorar a compreensão da fisiopatologia da doença e as opções terapêuticas.

Methodology in the epidemiological research of respiratory diseases and environmental pollution

There are complex and diverse methodological problems involved in the clinical and epidemiological study of respiratory diseases and their etiological factors. The association of urban growth, industrialization and environmental deterioration with respiratory diseases makes it necessary to pay more attention to this research area with a multidisciplinary approach. Appropriate study designs and statistical techniques to analyze and improve our understanding of the pathological events and their causes must be implemented to reduce the growing morbidity and mortality through better preventive actions and health programs. The objective of the article is to review the most common methodological problems in this research area and to present the most available statistical tools used.

Associação entre polimorfismo inserção/delecção da enzima conversora da angiotensina na diabetes mellitus tipo 2: estudo da população portuguesa

A Diabetes mellitus tipo 2 (DM2) é uma patologia de etiologia múltipla à qual estão associados vários factores genéticos. A Enzima Conversora da Angiotensina (ECA) tem sido alvo de vários estudos pela sua relação com factores pró-inflamatórios, pró-oxidantes e pró-fibrose, sendo o polimorfismo de Inserção/Delecção o mais estudado. Neste contexto, o objectivo deste estudo é assim verificar a distribuição deste polimorfismo numa amostra de indivíduos de nacionalidade portuguesa e verificar a sua possível associação com a DM2. Para tal, foram analisadas 87 amostras (controlos n =24 e diabéticos n =63) de indivíduos de nacionalidade portuguesa. As amostras foram submetidas a um processo de extracção de ADN, sendo posteriormente amplificadas por Polymerase Chain Reaction e analisadas por eletroforese em gel de agarose a 1%. Observou-se uma prevalência de 8% (n=7) com genótipo I/I, 38% (n=33) com genótipo I/D e 54% (n=47) com genótipo D/D. A amostra em estudo demonstrou assim estar sob o equilíbrio Hardy-Weinberg. Observou-se também uma associação entre níveis mais elevados de glicemia e o genótipo I/I (p=0,019). Na análise da utilização de insulina no controlo dos níveis de glicemia na DM2, observou-se uma maior proporção de indivíduos com genótipo D/D. Este estudo demonstra a importância do investimento da caracterização genética em patologias metabólicas multifactoriais como a DM2.