Wolbachia density and virulence attenuation after transfer into a novel host

The factors that control replication rate of the intracellular bacterium Wolbachia pipientis in its insect hosts are unknown and difficult to explore, given the complex interaction of symbiont and host genotypes. Using a strain of Wolbachia that is known to over-replicate and shorten the lifespan of its Drosophila melanogaster host, we have tracked the evolution of replication control in both somatic and reproductive tissues in a novel host/Wolbachia association. After transinfection (the transfer of a Wolbachia strain into a different species) of the over-replicating Wolbachia popcorn strain from D. metanogaster to Drosophila simulans, we demonstrated that initial high densities in the ovaries were in excess of what was required for perfect maternal transmission, and were likely causing reductions in reproductive fitness. Both densities and fitness costs associated with ovary infection rapidly declined in the generations after transinfection. The early death effect in D. simulans attenuated only slightly and was comparable to that induced in D. metanogaster. This study reveals a strong host involvement in Wolbachia replication rates, the independence of density control responses in different tissues, and the strength of natural selection acting on reproductive fitness.

Effect of maternal epidural analgesia on fetal intrapartum oxygen saturation

The use of maternal epidural analgesia in labor may be associated with nonreassuring fetal heart rate (FHR) patterns. Fetal oxygen saturation (FSpO(2)) monitoring may improve assessment of fetal well-being during this time. Mean FSpO(2) values were compared over seven 5-minute epochs: 5 minutes prior to an epidural event (combined insertion of epidural/top-up epidural analgesia and infusion pump bolus), to 30 minutes following the event, including possible effects of maternal position and FHR pattern on FSpO(2) values. Mean FSpO(2) values were significantly different between the 5 minutes prior (49.5%) versus 16-20 minutes (44.3%, p

Coordination and movement pathology: models of structure and function

Here we consider the role of abstract models in advancing our understanding of movement pathology. Models of movement coordination and control provide the frameworks necessary for the design and interpretation of studies of acquired and developmental disorders. These models do not however provide the resolution necessary to reveal the nature of the functional impairments that characterise specific movement pathologies. In addition, they do not provide a mapping between the structural bases of various pathologies and the associated disorders of movement. Current and prospective approaches to the study and treatment of movement disorders are discussed. It is argued that the appreciation of structure-function relationships, to which these approaches give rise, represents a challenge to current models of interlimb coordination, and a stimulus for their continued development. (C) 2002 Elsevier Science B.V. All rights reserved.

Infant mortality and low birth weight in cities of Northeastern and Southeastern Brazil

OBJECTIVE: To compare estimates of low birth weight (LBW), preterm birth, small for gestational age (SGA), and infant mortality in two birth cohorts in Brazil. METHODS: The two cohorts were performed during the 1990s, in São Luís, located in a less developed area in Northeastern Brazil, and Ribeirão Preto, situated in a more developed region in Southeastern Brazil. Data from one-third of all live births in Ribeirão Preto in 1994 were collected (2,839 single deliveries). In São Luís, systematic sampling of deliveries stratified by maternity hospital was performed from 1997 to 1998 (2,439 single deliveries). The chi-squared (for categories and trends) and Student t tests were used in the statistical analyses. RESULTS: The LBW rate was lower in São Luís, thus presenting an epidemiological paradox. The preterm birth rates were similar, although expected to be higher in Ribeirão Preto because of the direct relationship between preterm birth and LBW. Dissociation between LBW and infant mortality was observed, since São Luís showed a lower LBW rate and higher infant mortality, while the opposite occurred in Ribeirão Preto. CONCLUSIONS: Higher prevalence of maternal smoking and better access to and quality of perinatal care, thereby leading to earlier medical interventions (cesarean section and induced preterm births) that resulted in more low weight live births than stillbirths in Ribeirão Preto, may explain these paradoxes. The ecological dissociation observed between LBW and infant mortality indicates that the LBW rate should no longer be systematically considered as an indicator of social development.

Effects of breastfeeding and sucking habits on malocclusion in a birth cohort study

OBJECTIVE: To estimate the prevalence of malocclusion and to examine the effects of breastfeeding and non-nutritive sucking habits on dentition in six-year-old children. METHODS: A cross-sectional study was carried out nested into a birth cohort conducted in Pelotas, Southern Brazil, in 1999. A sample of 359 children was dentally examined and their mothers interviewed. Anterior open bite and posterior cross bite were recorded using the Foster & Hamilton criteria. Information regarding breastfeeding and non-nutritive sucking habits was collected at birth, in the first, third, sixth and 12th months of life, and at six years of age. Control variables included maternal schooling and child's birthweight, cephalic perimeter, and sex. Data were analyzed by Poisson regression. RESULTS: Prevalence of anterior open bite was 46.2%, and that of posterior cross bite was 18.2%. Non-nutritive sucking habits between 12 months and four years of age and digital sucking at age six years were the main risk factors for anterior open bite. Breastfeeding for less than nine months and regular use of pacifier between age 12 months and four years were risk factors for posterior cross bite. Interaction between duration of breastfeeding and the use of pacifier was identified for posterior cross bite. CONCLUSIONS: Given that breastfeeding is a protective factor for other diseases of infancy, our findings indicate that the common risks approach is the most appropriate for the prevention of posterior cross bite in primary or initial mixed dentition.

Contributo do iPad® para o desenvolvimento de crianças com necessidades educativas especiais

Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção do grau de Mestre em Ciências da Educação, Especialidade Intervenção Precoce

Prevalence of syphilis in pregnancy and prenatal syphilis testing in Brazil: Birth in Brazil study

OBJECTIVE Determine the coverage rate of syphilis testing during prenatal care and the prevalence of syphilis in pregnant women in Brazil. METHODS This is a national hospital-based cohort study conducted in Brazil with 23,894 postpartum women between 2011 and 2012. Data were obtained using interviews with postpartum women, hospital records, and prenatal care cards. All postpartum women with a reactive serological test result recorded in the prenatal care card or syphilis diagnosis during hospitalization for childbirth were considered cases of syphilis in pregnancy. The Chi-square test was used for determining the disease prevalence and testing coverage rate by region of residence, self-reported skin color, maternal age, and type of prenatal and child delivery care units. RESULTS Prenatal care covered 98.7% postpartum women. Syphilis testing coverage rate was 89.1% (one test) and 41.2% (two tests), and syphilis prevalence in pregnancy was 1.02% (95%CI 0.84;1.25). A lower prenatal coverage rate was observed among women in the North region, indigenous women, those with less education, and those who received prenatal care in public health care units. A lower testing coverage rate was observed among residents in the North, Northeast, and Midwest regions, among younger and non-white skin-color women, among those with lower education, and those who received prenatal care in public health care units. An increased prevalence of syphilis was observed among women with < 8 years of education (1.74%), who self-reported as black (1.8%) or mixed (1.2%), those who did not receive prenatal care (2.5%), and those attending public (1.37%) or mixed (0.93%) health care units. CONCLUSIONS The estimated prevalence of syphilis in pregnancy was similar to that reported in the last sentinel surveillance study conducted in 2006. There was an improvement in prenatal care and testing coverage rate, and the goals suggested by the World Health Organization were achieved in two regions. Regional and social inequalities in access to health care units, coupled with other gaps in health assistance, have led to the persistence of congenital syphilis as a major public health problem in Brazil.

Behavioral and synaptic circuit analysis in models of neuropsychiatric disorders: Dissecting the in vivo role of the postsynaptic density proteins nArgBP2 and Shank3 using genetic engineered mice

Dissertation presented to obtain the Ph.D degree in Biology

Occurrence of enteroparasites in day care centers in Botucatu (São Paulo State, Brazil) with emphasis on Cryptosporidium sp., Giardia duodenalis and Enterobius vermicularis

The occurrence of the enteroparasites was verified in 279 children (0 to 6 years) of four municipal day cares of Botucatu/SP. Three samples of each child's feces were collected and processed by the methods of Hoffman-Pons-Janner, Faust and Ritchie and subsequent coloration of the fecal smear by the methods of Auramina-O and Ziehl-Neelsen modified for diagnosis of Cryptosporidium sp. and Graham method for diagnosis of Enterobius vermicularis. Of the analyzed children we verified a prevalence of intestinal parasitism in 53.40%, and the most frequent parasite was Giardia duodenalis (26.88%). Significant association was verified among enteroparasitosis, family income, maternal education and age; the lowest enteroparasite frequency occurred in children of families with larger income and higher education. It was observed that G. duodenalis is more prevalent in children from 0 to 4 years and E. vermicularis is more frequent in children between three and four years old. The high enteroparasite prevalence in day cares suggests complex structure in its epidemiology, where factors beyond sanitation should be considered.

Perinatal Death: Epidemiology and Etiology

Perinatal mortality rate is an important mark to evaluate women and perinatal health care. It is of utmost importance to know causes and the evolution of its two components aiming to improve health care in different fields – sanitary conditions, diagnosis and treatment of infectious disease, immunisations, diagnosing and caring for medical diseases induced by pregnancy or directly related to it, providing skilled birth attendance, preventing birth asphyxia, preventing preterm birth complications and infections. In high-income countries the epidemiology varies mainly with social and economic conditions; in low-income countries, paired with poverty, undernutrition, superstition, lack of medical care, deficient basic sanitary conditions are also found. Also, in rich countries, responsible for 1% of deaths, data are published and improvements evaluated, while in low-income countries responsible for 99% of deaths numbers and causes are unknown, making difficult to implement cost effective interventions, a reason why “stillbirth rates in low-income countries are now where they were in high-income countries 50 to 100 years ago”. Knowledge on causes of death are very important as often what is needed are “simple” measures as improvement of sanitary conditions and immunisation programmes rather than high technologies. About four million babies dye each year in the first 28 days of life and another 3 million dye before birth in the third-trimester, with 98% occurring in low-income and middle income countries and more than 1 million occurring during labour and delivery. Classically stillbirths are the major component of perinatal mortality rate. Causes of death are even more difficult to know. In low-income countries a great proportion of women give birth at home. Worldwide the main causes of stillbirth are asphyxia due to obstructed labour, eclampsia, abruption placenta and umbilical cord complications - making valid the assumption that skilled birth attendance would decrease stillbirth; and infection - chorioamnioitis, syphilis and malaria. In high-income countries placental pathology and infection, congenital anomalies, complications of preterm birth and post term delivery, are the most common. If in low-income countries famine and lack of provisions and health care are common, in high-income countries, advanced maternal age and diabetes, obesity, hypertension, smoking, are frequent findings.

Cortisol and Anxiety Response to a Relaxing Intervention on Pregnant Women Awaiting Amniocentesis

Background: Stress and anxiety during pregnancy have been associated with premature and low birth weight babies, presumably through fetus over exposion to glucocorticoids. Antenatal stress also seems to have long-term effects upon infant development and adult health. However, medication for stress may carry risks to the expectant mother, therefore the efficacy of nonpharmacological interventions should be investigated. Methods: Pregnant women (n = 154) awaiting amniocentesis, were randomly assigned in the morning and the afternoon to three groups for 30 min: (1) listening to relaxing music, (2) sitting and reading magazines, and (3) sitting in the waiting-room. Before and after that period, they completed the Spielberger’s State and Trait anxiety inventory and provided blood samples for cortisol. The groups were then compared regarding change in cortisol levels and anxiety. Results: Maternal cortisol and state anxiety were correlated (r = 0.25, p = 0.04) in the afternoon, but not in the morning. The larger decreases in cortisol occurred in the music group ( 61.8 nmol/L, ANOVA: p = 0.01), followed by magazine, being differences among groups more pronounced in the morning. Women in the music group also exhibited the greater decreases in state anxiety ( p < 0.001). Younger mothers with less gestational age were on average the most anxious, and also the ones with greater decreases in cortisol and anxiety levels after relaxation. Conclusion: A relaxing intervention as short as 30 min, especially listening to music, decreases plasma cortisol and self-reported state anxiety score. Pregnant women might benefit from the routine practice of relaxation in the imminence of clinical stressful events.

Relationship between plasma creatinine concentration and glomerular filtration in preterm newborn infants

Fluid management and dosage regimens of drugs in preterm infants should be based on the glomerular filtration rate. The current methods to determine glomerular flitration rate are invasive, time-consuming, and expensive. In contrast, creatinine clearance can be easy obtained and quickly determined. The purpose of this study was to compare plasma creatinine on the third and seventh day of life in preterm newborn infants, to evaluate the influence of maternal creatinine, and to demonstrate creatinine clearance can be used as a reliable indicator of glomerular filtration rate. We developed a prospective study (1994) including 40 preterm newborns (gestational age < 37 weeks), average = 34 weeks; birth weight (average) = 1840 g, in the first week of life. Inclusion criteria consisted of: absence of renal and urinary tract anomalies; O2 saturation 3 92%; adequate urine output (>1ml/kg/hr); normal blood pressure; absence of infections and no sympathomimetic amines in use. A blood sample was collected to determine plasma creatinine (enzymatic method) on the third and seventh day of life and creatinine clearance (CrCl) was obtained using the following equation: , k = 0.33 in preterm infant All plasma creatinine determinations showed normal values [third day: 0.78 mg/dl ± 0.24 (mean ± SD)and seventh day: 0.67 mg/dl ± 0.31 - (p>0.05)]. Also all creatinine clearance at third and seventh day of life were normal [third day: 19.5 ml/min ± 5.2 (mean ± SD) and seventh day: 23.8 ml/min ± 7.3 - (p>0,05)]. All preterm infants developed adequate renal function for their respective gestational age. In summary, our results indicate that, for clinical practice, the creatinine clearance, using newborn length, can be used to estimate glomerular filtration rate in preterm newborn infants.

HIV-1: maternal prognosis

Profound modifications in the profile of patients are currently being observed within the epidemic context of AIDS, especially with respect to pauperization and feminization of the disease. The population most frequently affected is in the reproductive age, and among adults aged 18 to 24 years, the ratio is 1 man to 1 woman, a phenomenon occurring uniformly all over the world. One of the main challenges for HIV-1-infected pregnant women and their doctors is the effect of the interaction between HIV infection and pregnancy. The present article is a review of the literature; and its objective is to assess the influence of HIV-1 infection seen from the maternal perspective, with a discussion of immunologic function, maternal prognosis, and the HIV-abortion interface. At present, we cannot conclude that pregnancy has a short-term effect on the evolution of HIV infection, but the concomitance of HIV and pregnancy may adversely affect the prognosis of gestation, especially in view of its frequent association with increased abortion and puerperal morbidity rates.

The role of arl13b in cilia length regulation and in zebrafish development

RESUMO: Arl13b é uma importante proteína ciliar, presente em cílios primários e cílios móveis. Ratinhos mutantes para Arl13b têm comprimento dos cílios reduzido e defeitos nos B-túbulos dos cílios. Como consequência destes fenótipos, deficiências na Arl13b originam, em modelos animais, várias doenças congénitas, incluindo problemas no estabelecimento do eixo esquerda-direita, malformações cerebrais e deformações corporais. Nos seres humanos, deficiências na Arl13b levam a uma doença crónica congénita chamada Síndrome de Joubert. Por outro lado, a sobreexpressão de Arl13b origina cílios mais longos, no entanto existe uma ausência da caracterização dos fenótipos celulares e durante o desenvolvimento embrionário. Neste trabalho, quisemos explorar o efeito da sobre-expressão de Arl13b em embriões de peixezebra. Descobrimos que, ao nível ciliar, a sobre-expressão de Arl13b nas células aumenta o comprimento ciliar em cílios primários e móveis, no entanto, a esses cílios falta adequada acetilação da alfa-tubulina no citoesqueleto feito por microtúbulos. Os nossos resultados mostraram que esse efeito é específico de Arl13b sobre-expressão e quando se manipularam as enzimas responsáveis pela acetilação (Mec17) e pela de-acetilação (HDAC6) encontrámos uma sinergia potencial com ambas. Testámos ainda, que o aumento no comprimento ciliar não estava causalmente relacionado com a falta de acetilação, ou seja, os cílios com menos acetilação não eram necessariamente os mais longos. Também mostrámos que a sobre-expressão de Arl13b é capaz de restaurar o comprimento dos cílios em mutantes com cílios curtos e como isso pode ser explorado para um futuro potencial papel terapêutico para Arl13b. Em seguida, foi avaliado o impacto do aumento da quantidade de Arl13b no desenvolvimento embrionário do peixe-zebra. Observou-se que a sobre-expressão de Arl13b apresentava fenótipos muito fracos, quando comparados com a perda de função dos mutantes de Arl13b. Focados no inesperado fenótipo leve no estabelecimento do eixo esquerda-direita abordámos a questão através do estabelecimento de uma colaboração com matemáticos, descobrimos que os cílios mais longos que potencialmente têm a capacidade de movimentar mais fluido são atenuados por amplitudes de batimento menores, e, como resultado, estes longos cílios não prejudicam o movimento do fluido e consequentemente não afetam o estabelecimento dos padrões de esquerda-direita. Sugerimos assim que a Arl13b é um regulador chave, do comprimento ciliar. Descobrimos uma nova interação com as enzimas de acetilação/de-acetilação e levantamos novas hipóteses quanto aos mecanismos moleculares da função da Arl13b. Propomos um novo modelo para o mecanismo molecular da Arl13b na regulação do comprimento dos cílios onde podemos integrar os nossos resultados com os relatados na literatura. Este trabalho adiciona mais conhecimento para o mecanismo de ação da Arl13b e, portanto, fornece uma importante contribuição para o campo da investigação em cílios.---------------------------------------------------------------------------------------------------------------------- ABSTRACT: Arl13b is an important ciliary protein, present in primary and motile cilia. arl13b-/- mouse mutants have reduced cilia length and cilia B-tubule defects. As a consequence of these phenotypes, Arl13b loss of function animal models suffer from several congenital disorders including left-right problems, brain malformations and body deformations. In humans Arl13b depletion leads to a congenital chronic disease called Joubert Syndrome. On the other hand, overexpressing Arl13b leads to longer cilia but the characterization of the cellular and developmental phenotypes was missing. In this work we explore the effect of Arl13b overexpression in zebrafish embryos. We found that, at the ciliary level, Arl13b overexpression from 1 cell stage produces longer primary and motile cilia, but these cilia lack proper alpha tubulin acetylation of their microtubule cytoskeleton. Our results showed that this effect is specific from Arl13b overexpression and when we manipulated the enzymes responsible for acetylation, Mec17, and de-acetylation, HDAC6, we found a potential synergy of both mec17 knockdown and HDAC6 activity with Arl13b overexpression. We tested that the ciliary increase in length was not causally related to the lack of acetylation, meaning the more de-acetylated cilia were not necessarily the longer ones. We also showed that Arl13b overexpression is able to restore cilia length in short cilia mutants and how that may be explored to a potential future therapeutic role for Arl13b. Next, we evaluated the impact of increasing the amount of Arl13b in zebrafish embryonic development. We observed that Arl13b overexpression presented very mild phenotypes when compared to the loss of function mutants. We focused on the unexpected left-right mild phenotype and by establishing a mathematical modeling collaboration, we found out that the longer cilia generated force was attenuated by smaller beating amplitudes, and as a result, these long cilia were not impairing the cilia generated flow and the establishment of left-right patterning. We suggest that Arl13b is one key cilia length regulator. We disclosed a novel interaction with the acetylation / de-acetylation enzymes and raised new hypothesis as to the mechanisms of Arl13b function. We propose a new model for the Arl13b molecular mechanism of cilia length regulation where we integrate our findings with those reported in the literature. This work adds more knowledge to the Arl13b mechanism of action and therefore provides an important contribution to the cilia research field.

Flexural strengthening of RC beams using hybrid composite plate (HCP): experimental and analytical study

Hybrid Composite Plate (HCP) is a reliable recently proposed retrofitting solution for concrete structures, which is composed of a strain hardening cementitious composite (SHCC) plate reinforced with Carbon Fibre Reinforced Polymer (CFRP). This system benefits from the synergetic advantages of these two composites, namely the high ductility of SHCC and the high tensile strength of CFRPs. In the materialstructural of HCP, the ultra-ductile SHCC plate acts as a suitable medium for stress transfer between CFRP laminates (bonded into the pre-sawn grooves executed on the SHCC plate) and the concrete substrate by means of a connection system made by either chemical anchors, adhesive, or a combination thereof. In comparison with traditional applications of FRP systems, HCP is a retrofitting solution that (i) is less susceptible to the detrimental effect of the lack of strength and soundness of the concrete cover in the strengthening effectiveness; (ii) assures higher durability for the strengthened elements and higher protection to the FRP component in terms of high temperatures and vandalism; and (iii) delays, or even, prevents detachment of concrete substrate. This paper describes the experimental program carried out, and presents and discusses the relevant results obtained on the assessment of the performance of HCP strengthened reinforced concrete (RC) beams subjected to flexural loading. Moreover, an analytical approach to estimate the ultimate flexural capacity of these beams is presented, which was complemented with a numerical strategy for predicting their load-deflection behaviour. By attaching HCP to the beams’ soffit, a significant increase in the flexural capacity at service, at yield initiation of the tension steel bars and at failure of the beams can be achieved, while satisfactory deflection ductility is assured and a high tensile capacity of the CFRP laminates is mobilized. Both analytical and numerical approaches have predicted with satisfactory agreement, the load-deflection response of the reference beam and the strengthened ones tested experimentally.