Surgical outcomes following repeat non-penetrating glaucoma filtration surgery at a tertiary referral centre

Purpose:To determine the surgical outcomes of patients undergoing repeat deep sclerectomies with collagen implant (DSCI) at a tertiary referral centre. Methods:The medical notes of 208 patients undergoing multiple DSCI were reviewed. Those undergoing repeat DSCI were identified and post operative data for each DSCI were analysed. Group A: the first DSCI; group B: second DSCI; group C: third DSCI. Results:Mean age was 66.8 ±13.0 years. At 12 months, percentage of mean IOP reduction in groups were 18%, 24% and 17% respectively. Mean interval to starting glaucoma medications, re-operation, mitomycin injection and goniopuncture all decreased as the number of operations increased. There was a significant reduction in complete success rates between groups A and B and groups B and C. Few minor complications were observed in all 3 groups. Conclusions:Despite the possibility of bleb independent outflow pathways in patients undergoing non-penetrating surgery, there are significantly reduced success rates in eyes undergoing repeat DSCI. This has important implications for the choice of subsequent operations in patients who have failed non-penetrating filtration surgery.

Division of labour influences the rate of ageing in weaver ant workers.

The evolutionary theory of ageing predicts that the timing of senescence has been primarily shaped by the extrinsic mortality rate, which causes selection intensity to decline over time. One difficulty in testing the evolutionary theory of ageing is that extrinsic mortality risk is often confounded with body size and fecundity, which may also directly affect lifespan. Social insects with a pronounced division of labour between worker castes provide a unique opportunity to study the direct effect of extrinsic mortality on the evolution of ageing rates independently of body size, reproductive effort and genetic configuration. In the weaver ant, Oecophylla smaragdina, the major (large) workers perform the risky tasks outside the nest, while the minor (small) workers stay within the highly protected arboreal nest. Hence, this pronounced division of labour is associated with high differences in extrinsic mortality risks. The evolutionary theory of ageing predicts that the minor workers should have a longer intrinsic lifespan than the major workers. In line with this prediction, we found that in a protected environment the minor workers lived significantly longer than the major workers did. Hence, the ageing rate appears to have been moulded by variation in the extrinsic mortality rate independently of size, reproductive effort and genetic configuration.

Effect of food on immature development, consumption rate, and relative growth rate of Toxorhynchites splendens (Diptera: Culicidae), a predator of container breeding mosquitoes

Food utilization by the larvae of Toxorhynchites splendens (Wiedemann) was studied in the laboratory by offering larvae of Aedes aegypti Linnaeus, Anopheles stephensi (Liston), and Culex quinquefasciatus (Say). Quantitative analyses of data indicated that immature development was significantly faster with increase in food availability. The regression analysis showed that the degrees of the relationship between immature duration (Id) and food availability were higher when offered early instars of prey (first and second instars) than late instars. Consumption rate (Cr) of the predator increased with increase in food availability and this relationship was highly significant when larvae of An. stephensi were offered as food. Consumption rate to food level decreased with increase in the age class of the prey. There was a significant negative correlation between Id and Cr. This aspect helps to increase population turnover of T. splendens in a shorter period when the prey is abundant. Conversely, the predator compensated the loss in daily food intake at low food level by extending Id thereby attains the minimum threshold pupal weight for adult emergence. There was an increase in the relative growth rate (RGR) of the predator when An. stephensi was offered as prey and this was related to the high protein content of the prey per body weight. There was a positive correlation between Cr and RGR. This adaptive life characteristic strategy of this predator is useful for mass-rearing for large scale field release programmes in the control of container breeding mosquitoes is discussed.

The effects of temperature change on the infection rate of Biomphalaria glabrata with Schistosoma mansoni

The aim of this study was to investigate the influence of temperature on the development of Schistosoma mansoni infections in Biomphalaria glabrata. The snails were infected at 15, 20, and 30ºC, and the cercarial release was analyzed after 30 and 60 days post-infection. Our results showed that a decrease in the temperature has a substantial influence on the development of S. mansoni infection in B. glabrata, with significant differences (p < 0.05) between 15 and 30ºC. These data could provide a better understanding of the epidemiological aspects of schistosomiasis.

Seroepidemiology of hepatitis B virus infection and high rate of response to hepatitis B virus Butang®vaccine in adolescents from low income families in Central Brazil

In order to evaluate the seroepidemiology and response to Butang® vaccine in adolescents from low income families in Central Brazil, blood samples of 664 adolescents were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs) markers, and multiple logistical regression analysis was carried out to determine variables associated with hepatitis B virus (HBV) infection markers. further, three 20 µg butang® vaccine doses were offered to all susceptible individuals (n = 304). Among those who accepted them (n = 182), the seroresponse was evaluated in 170 individuals by quantitative anti-HBs. an overall hbv prevalence of 5.9% was found: four adolescents were HBsAg positive, 24 were anti-HBc, anti-HBs-reactive, and 11 were anti-HBc only. The analyse of risk factors showed that age 16-19 years, place of birth outside Goiás, school B and body piercing were statistically associated with HBV infection markers (p < 0.05). All 170 adolescents responded to butang®, and a geometric mean titer (gmt) of 4344 mui/ml was obtained. these results reinforce the importance of hepatitis b vaccine in adolescents despite of the hbv regional endemicity, and suggest that three doses of 20 µg of the butang® should guarantee protective anti-hbs levels to individuals at a critical time for hepatitis b acquiring such as latter adolescence and adulthood.

Man biting rate seasonal variation of malaria vectors in Roraima, Brazil

Malaria control has been directed towards regional actions where more detailed knowledge of local determinants of transmission is of primary importance. This is a short report on range distribution and biting indices for Anopheles darlingi and An. albitarsis during the dry and rainy season that follows river level variation in a savanna/alluvial forest malaria system area in the Northern Amazon Basin. Distribution range and adult biting indices were at their highest during the rainy season for both An. darlingi and An. albitarsis. During the rainy season the neighboring alluvial forest was extensively flooded. This coincided with highest rates in malaria transmission with case clustering near the river. As the river receded, anopheline distribution range and density decreased. This decrease in distribution and density corresponded to a malaria decrease in the near area. An exponential regression function was derived to permit estimations of An. darlingi distribution over specified distances. Anopheline spatio-temporal variations lead to uneven malaria case distribution and are of important implications for control strategies.

Analyse UBM du site de filtration après sclérectomie profonde postérieure modifiée utillisant un tube Ex-PRESS? X-50

Purpose: To study the filtering site using ultrasound biomicroscopy. (UBM) after posterior deep sclerectomy with Ex-PRESS? X-50 implant in patients undergoing filtering surgery.¦Methods: Twenty-six patients that participated in this prospective, non comparative study underwent a posterior deep sclerectomy and an Ex- PRESS? X-50 tube implantation. Clinical outcome factors recorded include: intraocular pressure, number of antiglaucoma medications, best corrected visual acuity (BCVA), frequency and types of complications. Six months postoperatively, an ultrasound biomicroscopy examination was performed.¦Results: Mean follow up was 12.0±3.4 months. Mean IOP decreased from 21 ±5.7 mmHg to 12.4±3 mmHg. At last follow-up examination, 65% of eyes had a complete success and 30% a qualified success. The mean number of antiglaucoma medications decreased from 2.5±1.2 preoperatively to 0.7±1 at the last follow-up postoperatively. BCVA was not changed. 27 complications were observed. On the UBM images, the mean intrascleral space volume was 0.25±0.27 mm3 and no relationship was found between volume and intraocular pressure reduction. We noted in 5/26 (19%) eyes a suprachoroïdal hypoechoic. Low-reflective blebs (L-type) were the most common: 15/26 (58%). No correlation between UBM findings and surgical success was evident.¦Conclusions: Deep sclerectomy with Ex-PRESS? X-50 tube implantation seems an efficient glaucoma surgery. It allows satisfactory IOP reduction with a low number of post operative complications. The advantages of deep sclerectomy with collagen implant are maintained with this modified technique. In both, the same reflective types of filtering blebs are present (high, low, encapsulated and flat). The UBM underlines the three mechanisms of aqueous humor resorption previously identified but no correlation with surgical success can be proved.¦-¦Ce travail de thèse est une analyse par ultrasonographic biomicroscopique (UBM) du site de filtration après sclérectomie profonde postérieure modifiée avec implantation d'un tube Ex- PRESS? X-50.¦Vingt six patients atteints d'un glaucome à angle ouvert, ont participé à cette étude prospective et non-comparative. Le critère d'inclusion est un glaucome à angle ouvert non contrôlé malgré un traitement topique maximal.¦Différents types de chirurgie filtrante sont effectués dans la chirurgie du glaucome dont la trabéculectomie et la sclérectomie profonde.¦L'intervention chirurgicale pratiquée dans cette étude consiste en l'implantation d'un tube Ex-PRESS? X-50 de format défini (3 mm de longueur et 50 μπι de diamètre interne) dans la chambre antérieure,au niveau du trabeculum, sous un volet scléral, ce qui permet le drainage de l'humeur aqueuse vers les espaces sous-conjonctivaux, avec diminution de la pression intraoculaire.¦Cette technique implique uniquement une dissection d'un volet scléral superficiel , sans volet scléral profond comme d'une sclérectomie profonde classique.¦Les modes de fonctionnement de cette sclérectomie profonde modifiée sont explorés par UBM, qui donne des images à haute résolution, semblables à des coupes anatomiques. Le volume de l'espace intrascléral créé artificiellement peut en effet être mesuré et mis en corrélation avec la pression intraoculaire et donc avec le taux de succès. Les différents types d'échogénécité de la bulle de filtration sous-conjonctivale provoquée par la dérivation de l'humeur aqueuse sont également observés. La présence éventuelle d'une filtration supplémentaire au niveau choroïdien est aussi détectée.¦De février 2007 à juin 2008, nous avons suivi chez les vingt six yeux des vingt six patients le volume intrascléral, la filtration sous-conjonctivale et la filtration choroïdienne le cas échéant, de même que l'acuité visuelle, la pression intraoculaire, le nombre de traitement antihypertenseur topique et les complications.¦Les résultats démontrent une réduction de 41 % par rapport à la pression intraoculaire préopératoire, ce qui est statistiquement significatif (p<0.0005). En ce qui concerne l'acuité visuelle, les valeurs demeurent stables. Par ailleurs, le nombre de médicaments antiglaucomateux diminue de façon significative de 2.5 ± 1.2 en préopératoire à 0.7 ± 1.0 au dernier examen (p<0.0005). Le volume de l'espace intrascléral, apparaissant toujours en échographie d'aspect fusiforme, n'est pas corrélé de façon significative avec un meilleur succès chirurgical bien que l'on aperçoive une tendance à une corrélation entre un plus grand volume et une pression intraoculaire plus basse.¦La classification la bulle de filtration se fait selon les 4 catégories de bulle de filtration décrites dans la littérature. La répartition révèle une majorité de type L soit hypoéchogène: 15/26 (58%) et une proportion identique, soit, 4/26 (16%), de bulles hyperéchogènes (type H) et encapsulées (type E); les bulles de filtration plates et hyperéchogènes (type F) sont les moins nombreuses 3/26 (11 %).¦La ligne hyporéflective visible dans 19 % des cas entre la sclère et la choroïde représentant potentiellement un drainage suprachoroïdien, n'est pas associée statistiquement à une meilleure filtration et une pression intraoculaire plus basse mais demeure une troisième voie de filtration, en plus de la filtration sous-conjonctivale et intrasclérale.¦En conclusion, cette technique différente, offrant une plus grande sécurité et des résultats satisfaisants sur l'abaissement de la pression intraoculaire, peut être, dans certains cas, une alternative à la sclérectomie profonde classique ,dont elle partage les mécanismes de filtration objectivés par ultrasonographic biomicrioscopique.

(.)VO(2) and EMG activity kinetics during moderate and severe constant work rate exercise in trained cyclists.

The purpose of this study was to compare O(2) uptake ((.)VO(2)) and muscle electromyography activity kinetics during moderate and severe exercise to test the hypothesis of progressive recruitment of fast-twitch fibers in the explanation of the VO(2) slow component. After an incremental test to exhaustion, 7 trained cyclists (mean +/- SD, 61.4 +/- 4.2 ml x min(-1) x kg(- 1)) performed several square-wave transitions for 6 min at moderate and severe intensities on a bicycle ergometer. The (.)VO(2) response and the electrical activity (i.e., median power frequency, MDF) of the quadriceps vastus lateralis and vastus medialis of both lower limbs were measured continuously during exercise. After 2 to 3 min of exercise onset, MDF values increased similarly during moderate and severe exercise for almost all muscles whereas a (.)VO(2) slow component occurred during severe exercise. There was no relationship between the increase of MDF values and the magnitude of the (.)VO(2) slow component during the severe exercise. These results suggest that the origin of the slow component may not be due to the progressive recruitment of fast-twitch fibers.

Relation of heart rate to percent VO2 peak during submaximal exercise in the heat.

We tested the hypothesis that elevation in heart rate (HR) during submaximal exercise in the heat is related, in part, to increased percentage of maximal O(2) uptake (%Vo(2 max)) utilized due to reduced maximal O(2) uptake (Vo(2 max)) measured after exercise under the same thermal conditions. Peak O(2) uptake (Vo(2 peak)), O(2) uptake, and HR during submaximal exercise were measured in 22 male and female runners under four environmental conditions designed to manipulate HR during submaximal exercise and Vo(2 peak). The conditions involved walking for 20 min at approximately 33% of control Vo(2 max) in 25, 35, 40, and 45 degrees C followed immediately by measurement of Vo(2 peak) in the same thermal environment. Vo(2 peak) decreased progressively (3.77 +/- 0.19, 3.61 +/- 0.18, 3.44 +/- 0.17, and 3.13 +/- 0.16 l/min) and HR at the end of the submaximal exercise increased progressively (107 +/- 2, 112 +/- 2, 120 +/- 2, and 137 +/- 2 beats/min) with increasing ambient temperature (T(a)). HR and %Vo(2 peak) increased in an identical fashion with increasing T(a). We conclude that elevation in HR during submaximal exercise in the heat is related, in part, to the increase in %Vo(2 peak) utilized, which is caused by reduced Vo(2 peak) measured during exercise in the heat. At high T(a), the dissociation of HR from %Vo(2 peak) measured after sustained submaximal exercise is less than if Vo(2 max) is assumed to be unchanged during exercise in the heat.

Prevalence of acute toxoplasmosis infection among 41,112 pregnant women and the mother-to-child transmission rate in a public hospital in South Brazil

Untreated acute toxoplasmosis among pregnant women can lead to serious sequelae among newborns, including neurological impairment and blindness. In Brazil, the risk of congenital toxoplasmosis (CTox) has not been fully evaluated. Our aim was to evaluate trends in acute toxoplasmosis prevalence from 1998-2005, the incidence of CTox and the rate of mother-to-child transmission (MTCT). A cross-sectional study was undertaken to dentify patients who fit the criteria for acute toxoplasmosis during pregnancy. Exposed newborns were included in a historical cohort, with a median follow-up time of 11 months, to establish definite diagnosis of CTox. Diagnoses for acute infection in pregnancy and CTox were based on European Research Network on Congenital Toxoplasmosis criteria. In 41,112 pregnant women, the prevalence of acute toxoplasmosis was 4.8/1,000 women. The birth prevalence of CTox was 0.6/1,000 newborns [95% confidence interval (CI): 0.4-0.9]. During the follow-up study, 12 additional cases were detected, increasing the CTox rate to 0.9/1,000 newborns (95% CI: 0.6-1.3). Among the 200 newborns exposed to Toxoplasma gondii,there were 37 babies presenting diagnostic criteria of CTox, leading to an MTCT rate of 18.5% (95% CI: 13.4-24.6%). The additional cases identified during follow-up reinforce the need for serological monitoring during the first year of life, even in the absence of evidence of congenital infection at birth.

Evolutionary implications of a high selfing rate in the freshwater snail Lymnaea truncatula.

Self-compatible hermaphroditic organisms that mix self-fertilization and outcrossing are of great interest for investigating the evolution of mating systems. We investigate the evolution of selfing in Lymnaea truncatula, a self-compatible hermaphroditic freshwater snail. We first analyze the consequences of selfing in terms of genetic variability within and among populations and then investigate how these consequences along with the species ecology (harshness of the habitat and parasitism) might govern the evolution of selfing. Snails from 13 localities (classified as temporary or permanent depending on their water availability) were sampled in western Switzerland and genotyped for seven microsatellite loci. F(IS) (estimated on adults) and progeny array analyses (on hatchlings) provided similar selfing rate estimates of 80%. Populations presented a low polymorphism and were highly differentiated (F(ST) = 0.58). Although the reproductive assurance hypothesis would predict higher selfing rate in temporary populations, no difference in selfing level was observed between temporary and permanent populations. However, allelic richness and gene diversity declined in temporary habitats, presumably reflecting drift. Infection levels varied but were not simply related to either estimated population selfing rate or to differences in heterozygosity. These findings and the similar selfing rates estimated for hatchlings and adults suggest that within-population inbreeding depression is low in L. truncatula.

Le taux de détresse respiratoire du nouveau-né augmente, celui des césariennes aussi: et si ce n'était pas un hasard? [Respiratory distress of the neonate and the rate of caesarean section have increased over the last 30 years. Is there a link?]

Ces trente dernières années, on note en Suisse une augmentation significative de l'incidence du syndrome de détresse respiratoire (SDR) chez le nouveau-né (NN), touchant particulièrement les enfants avec un poids de naissance >2500 g. En même temps, le taux des césariennes (CS) s'est aussi accru. Une explication pour une éventuelle corrélation entre les deux évolutions est une augmentation en particulier des CS électives qui ont tendance à être planifiées à un terme précoce pour éviter la mise en travail spontanée. Suite à cela, le foetus est privé de différents mécanismes qui favorisent l'adaptation pulmonaire périnatale. Les bénéfices réels de la CS sur la morbidité tant foetale que maternelle ne doivent pas faire oublier que la CS est un facteur de risque pour le SDR du NN. Ce risque peut être diminué efficacement en planifiant une CS élective après 39 semaines révolues. In Switzerland, the rate of respiratory distress in neonates needing hospitalization has doubled over the last thirty years, concerning in particular babies weighing more than 2500 g. In the same time, the rate of Caesarean section (CS) has also multiplied. We suppose that a link between the two evolutions might be the increase of elective CS. They tend to be planned early at term to avoid the onset of spontaneous labour As a consequence, the foetus is deprived of different mechanisms helping pulmonary transition around birth. The potential benefits of CS regarding morbidity of foetus and mother should not overshadow that CS is a significant risk factor for respiratory problems of the neonate. This risk could be dramatically decreased by planning elective CS only after completed 39 weeks of gestation

Influences of body weight, body composition, and substrate oxidation rate on resting postabsorptive glucose production and gluconeogenesis.

OBJECTIVE: To determine the influence of body weight, fat mass, and fat distribution on resting endogenous glucose production in healthy lean and overweight individuals. DESIGN: measurements were performed in the resting postabsorptive state in individuals receiving an unrestricted diet. SETTING: Institute of Physiology of Lausanne University. MEASUREMENTS: resting post absorptive glucose production, glycogenolysis and gluconeogenesis; resting energy expenditure and net substrate oxidation. RESULTS: Endogenous glucose production was positively correlated with body weight, lean body mass, energy expenditure and carbohydrate oxidation. Gluconeogenesis was positively correlated with net lipid oxidation and energy expenditure, and negatively correlated with net carbohydrate oxidation. No correlation with body fat or fat distribution was observed. CONCLUSIONS: Gluconeogenesis shows a large interindividual variability. Net lipid oxidation and not body fat appears to be a major determinant of gluconeogenesis.