Evaluation of Chemical and Physical-morphological Factors as Potential Determinants of Biomphalaria pfeifferi (Krauss, 1848) Distribution

This study was carried out in five sites along a small perennial river system in south-central Tanzania, which had been identified as the focus for transmission of intestinal schistosomiasis in the area. Malacological surveys preceding the study showed a focal distribution of Biomphalaria pfeifferi, intermediate host snail of Schistosoma mansoni, the snails being present in three sites but absent from the other two sites. The objective of this study was to evaluate to what extent chemical and/or physical-morphological factors determine the distribution of B. pfeifferi between these five sites. It was found that none of the chemical constituents in the waters examined were outside the tolerance range of B. pfeifferi snails. Moreover, the composition of water from B. pfeifferi-free sites was not different from that in those sites where snails occurred. Furthermore, none of the physical-morphological constituents seemed likely to be a determinant for the absence of B. pfeifferi. In view of these findings, and those of previous studies, it is concluded that the focal distribution of B. pfeifferi cannot be associated with a single environmental factor and is rather the result of more complex interactions of habitat factors

Improvement in coronary circulatory function in morbidly obese individuals after gastric bypass-induced weight loss: relation to alterations in endocannabinoids and adipocytokines.

AIMS: To investigate the effect of surgical gastric bypass-induced weight loss and related alterations in endocannabinoids (ECs) and adipocytokine plasma levels on coronary circulatory dysfunction in morbidly obese (MOB) individuals. METHODS AND RESULTS: Myocardial blood flow (MBF) responses to cold pressor test (CPT) from rest (ΔMBF) and during pharmacologically induced hyperaemia were measured with &supl;³N-ammonia PET/CT in 18 MOB individuals with a body mass index (BMI) > 40 kg/m² at baseline and after a median follow-up period of 22 months. Gastric bypass intervention decreased BMI from a median of 44.8 (inter-quartile range: 43.3, 48.2) to 30.8 (27.3, 34.7) kg/m² (P < 0.0001). This decrease in BMI was accompanied by a marked improvement in endothelium-related ΔMBF to CPT and hyperaemic MBFs, respectively [0.34 (0.18, 0.41) from 0.03 (-0.08, 0.15) mL/g/min, P = 0.002; and 2.51 (2.17, 2.64) from 1.53 (1.39, 2.18) mL/g/min, P < 0.001]. There was an inverse correlation between decreases in plasma concentrations of the EC anandamide and improvement in ΔMBF to CPT (r = -0.59, P = 0.009), while increases in adiponectin plasma levels correlated positively with hyperaemic MBFs (r = 0.60, P = 0.050). Conversely, decreases in leptin plasma concentrations were not observed to correlate with the improvement in coronary circulatory function (r = 0.22, P = 0.400, and r = -0.31, P = 0.250). CONCLUSIONS: Gastric bypass-related reduction of BMI in MOB individuals beneficially affects coronary circulatory dysfunction. The dysbalance between ECs and adipocytokines appears to be an important determinant of coronary circulatory function in obesity.

Inhibition of antigen-induced T-cell clone proliferation by antigen-specific antibodies.

Attempts to inhibit the recognition of soluble antigens by T lymphocytes using antibodies specific for the antigen in question have been uniformally unsuccessful, in contrast to the observed specific inhibition of antibody generation by B cells. One exception is the unique situation whereby anti-hapten antisera inhibit the T-cell proliferative responses observed when hapten-specific T lymphocytes or clones are cultured with hapten-derivatized cells or proteins. The inability to inhibit T-cell functions by antigen-specific antibodies has been interpreted in several ways: (1) T cells possess a different repertoire from B cells; (2) the antibodies tested recognize epitopes present on the native antigen, whereas T cells recognize non-native (processed) structures; (3) the antigenic determinant(s) recognized by T cells on the surface of antigen presenting cells are either not accessible to antibodies, or are present in low amounts. The development of antigen-specific T-cell clones and monoclonal antibodies both specific for the same antigenic determinants now allows this question to be investigated definitively. Here, we report for the first time the specific inhibition of antigen-induced T-cell clone proliferation by a monoclonal antibody directed against the relevant soluble protein antigen.

La prueba testifical en el proceso penal ¿De libre valoración?

La prova testifical és una de les proves principals del procés penal, és pel que s'ha intentat donar una visió de quins són els factors que afecten la seua validesa, tant des d'un punt de vista personal com processal, per a després marcar unes pautes que ha de seguir qualsevol jutge per a arribar a la convicció que la dita prova testifical pot enervar la presumpció d'innocència. El treball consisteix en respondre a la pregunta elemental que si realment el Jutge o Tribunal té plena llibertat per valorar la prova testifical en el procés penal, sobre aquesta qüestió es va a desenvolupar el treball, però sempre haurem de respectar uns principis bàsics en el procés penal, i a partir de que aquests principis li donin validesa a aquesta prova, podrem dir que el Jutge a *quo té plena llibertat per arribar a determinar si realment aquesta prova testifical trenca amb la presumpció d'innocència, sense que els tribunals d'instàncies superiors puguin modificar aspectes subjectius d'aquesta valoració sobre la base del principi de inmediació. També és cert, que la casuística en matèria de testimonis és immensa, per la qual cosa s'ha intentat analitzar cada cas particular a fi d'integrar-ho dins dels principis bàsics establerts en el procés penal, i així determinar quan es pot donar validesa a aquesta prova, i quins són els factors que ha de tenir en compte el Jutge per valorar-los com a prova determinant de càrrec o de descàrrec.

Industrial Location and Space: New Insights

This paper tries to resolve some of the main shortcomings in the empirical literature of location decisions for new plants, i.e. spatial effects and overdispersion. Spatial effects are omnipresent, being a source of overdispersion in the data as well as a factor shaping the functional relationship between the variables that explain a firm’s location decisions. Using Count Data models, empirical researchers have dealt with overdispersion and excess zeros by developments of the Poisson regression model. This study aims to take this a step further, by adopting Bayesian methods and models in order to tackle the excess of zeros, spatial and non-spatial overdispersion and spatial dependence simultaneously. Data for Catalonia is used and location determinants are analysed to that end. The results show that spatial effects are determinant. Additionally, overdispersion is descomposed into an unstructured iid effect and a spatially structured effect. Keywords: Bayesian Analysis, Spatial Models, Firm Location. JEL Classification: C11, C21, R30.

Environmental determinants of infectious and parasitic diseases

A review of the role of the environment as a determinant of infectious and parasitic diseases is presented. Historical considerations and the several environmental classifications of diseases are introduced. In a broader perspective the subject is analyzed in view of the emergence of the environmental health area, with its new paradigms. A review of epidemiological studies about environmental sanitation conditions and measures is presented, analyzing the conclusions derived from 256 studies. Finally, an epidemiological study carried out in Betim, Minas Gerais is briefly described, in order to illustrate the potentiality of this kind of study. Setting priorities of interventions regarding diarrhea control was the aim of this investigation. Conclusion about the role of this approach to optimize preventive measures for the control of infectious and parasitic diseases, of sound importance to the reality of the developing world, is stated.

Epidemiology and Anthropology: an integrated approach dealing with bio-socio-cultural aspects as strategy for the control of endemic diseases

The control of endemic diseases has not attained the desired level of effectiveness in spite of the use of modern efficient thecnologies. The classic interventionist approach for the control of schistosomiasis is centered on systemic control of the snail hosts combined to large scale medical treatment and is usually carried out without social preocupation due to the assisted communities. It is easy to understand the interest and the ethical compromise of public health research while producing studies in which the biological and social determinants as well as the cultural components should be considered and also encompass the historical dimensions and symbolic representations. In face of the recent political decision in favor of decentralizations of health administration to municipal level, we suggest, in the present paper, an integrated approach for the epidemiological diagnosis of an endemic situation at local level. Theoretical and methodological aspects from both, epidemiology and anthropology are discussed. Epidemiological methods can be used to detect the dependent variables (those related to the human infection) and the independent variables (demographic, economic, sanitary and social). Another methodological approach of anthropological /etnographic nature can be conducted in order to make an articulation of the knowledge on the various dimensions or determinant levels of the disease. Mutual comprehension, between researchers and the people under investigation, on the dynamic transmission process would be relevant for a joint construction, at local level, of programmed actions for the control of endemic diseases. This would extend reflections on the health/disease process as a whole.

Nominal plural marking of nonce words in child Spanish

This study addresses the issue of Spanish plural marking considering data from three sources: existent words, loan words and nonce words. Specifically, we are interested in the role of stress placement and word-final sound in the use of /-es/ for plural formation. We present data concerning the interaction of these two features for children and adults. Our findings suggest that this phenomenon is a classic example of over generalization in acquisition. Stress does not seem a determining feature by itself. Its main effect is produced when it interacts with the structure of the syllable

The degradation of HFR1, a putative bHLH class transcription factor involved in light signaling, is regulated by phosphorylation and requires COP1.

All developmental transitions throughout the life cycle of a plant are influenced by light. In Arabidopsis, multiple photoreceptors including the UV-A/blue-sensing cryptochromes (cry1-2) and the red/far-red responsive phytochromes (phyA-E) monitor the ambient light conditions. Light-regulated protein stability is a major control point of photomorphogenesis. The ubiquitin E3 ligase COP1 (constitutively photomorphogenic 1) regulates the stability of several light-signaling components. HFR1 (long hypocotyl in far-red light) is a putative transcription factor with a bHLH domain acting downstream of both phyA and the cryptochromes. HFR1 is closely related to PIF1, PIF3, and PIF4 (phytochrome interacting factor 1, 3 and 4), but in contrast to the latter three, there is no evidence for a direct interaction between HFR1 and the phytochromes. Here, we show that the protein abundance of HFR1 is tightly controlled by light. HFR1 is an unstable phosphoprotein, particularly in the dark. The proteasome and COP1 are required in vivo to degrade phosphorylated HFR1. In addition, HFR1 can interact with COP1, consistent with the idea of COP1 directly mediating HFR1 degradation. We identify a domain, conserved among several bHLH class proteins involved in light signaling , as a determinant of HFR1 stability. Our physiological experiments indicate that the control of HFR1 protein abundance is important for a normal de-etiolation response.

Confounding effects of heart rate on pulse wave velocity in paced patients with a low degree of atherosclerosis.

BACKGROUND: Pulse wave velocity (PWV), an index of arterial wall stiffness, is modulated by blood pressure (BP). Whether heart rate (HR) is also a modulator of PWV is controversial. Recent research involving mainly patients with high aortic PWV have found either no change or a positive correlation between the two. Given that PWV is increasingly being measured in cardiovascular studies, the relationship between HR and PWV should be known in patients with preserved arterial wall elasticity. OBJECTIVE: The aim of this study was to evaluate the importance of HR as a determinant of the variability in PWV in patients with a low degree of atherosclerosis. DESIGN AND METHODS: Fourteen patients (five female, nine male; aged 68 +/- 8 years) were evaluated post pacemaker implantation due to sick sinus or carotid hypersensitivity syndromes. Carotid-femoral PWV was measured at rest and during atrial pacing at 80, 90 and 100 bpm (paced HR). Arterial femoral blood flow (AFBF) was measured by echodoppler. RESULTS: PWV increased from 6.2 +/- 1.5 m/s (mean +/- SD) during resting sinus rhythm (HR 62 +/- 8 bpm; mean +/- SD) to 6.8 +/- 1.0, 7.0 +/- 0.9, and 7.6 +/- 1.1 m/s at pacing rates of 80, 90 and 100 bpm, respectively (P < 0.0001). Systolic (SBP) and mean blood pressure (MBP) remained constant at all HR levels, whereas AFBF increased in a linear fashion. CONCLUSIONS: These results demonstrate that even in patients with a low degree of atherosclerosis, HR is a potential modulator of carotid-femoral PWV.

Determinants of generic drug substitution in Switzerland.

Background: Since generic drugs have the same therapeutic effect as the original formulation but at generally lower costs, their use should be more heavily promoted. However, a considerable number of barriers to their wider use have been observed in many countries. The present study examines the influence of patients, physicians and certain characteristics of the generics' market on generic substitution in Switzerland.Methods: We used reimbursement claims' data submitted to a large health insurer by insured individuals living in one of Switzerland's three linguistic regions during 2003. All dispensed drugs studied here were substitutable. The outcome (use of a generic or not) was modelled by logistic regression, adjusted for patients' characteristics (gender, age, treatment complexity, substitution groups) and with several variables describing reimbursement incentives (deductible, co-payments) and the generics' market (prices, packaging, co-branded original, number of available generics, etc.).Results: The overall generics' substitution rate for 173,212 dispensed prescriptions was 31%, though this varied considerably across cantons. Poor health status (older patients, complex treatments) was associated with lower generic use. Higher rates were associated with higher out-of-pocket costs, greater price differences between the original and the generic, and with the number of generics on the market, while reformulation and repackaging were associated with lower rates. The substitution rate was 13% lower among hospital physicians. The adoption of the prescribing practices of the canton with the highest substitution rate would increase substitution in other cantons to as much as 26%.Conclusions: Patient health status explained a part of the reluctance to substitute an original formulation by a generic. Economic incentives were efficient, but with a moderate global effect. The huge interregional differences indicated that prescribing behaviours and beliefs are probably the main determinant of generic substitution.

Bloodmeal microfilariae density and the uptake and establishment of Wuchereria bancrofti infections in Culex quinquefasciatus and Aedes aegypti

The relationship between ingestion of microfilariae (mf), production of infective larvae (L3) and mf density in human blood has been suggested as an important determinant in the transmission dynamics of lymphatic filariasis. Here we assess the role of these factors in determining the competence of a natural vector Culex quinquefasciatus and a non vector Aedes aegypti to transmit Wuchereria bancrofti. Mosquitoes were infected via a membrane feeding procedure. Both mosquito species ingested more than the expected number of microfilariae (concentrating factor was 1.28 and 1.81 for Cx. quinquefasciatus and Ae. aegypti, respectively) but Cx. quinquefasciatus ingested around twice as many mf as Ae. aegypti because its larger blood meal size. Ae. aegypti showed a faster mf migration capacity compared to Cx. quinquefasciatus but did not allow parasite maturation under our experimental conditions. Similar proportions of melanized parasites were observed in Ae. aegypti (2.4%) and Cx. quinquefasciatus (2.1%). However, no relationship between rate of infection and melanization was observed. We conclude that in these conditions physiological factors governing parasite development in the thorax may be more important in limiting vectorial competence than the density of mf ingested.

The determinants of YIc's R&D activity

This paper examines the determinants of young innovative companies’ (YICs) R&D activities taking into account the autoregressive nature of innovation. Using a large longitudinal dataset comprising Spanish manufacturing firms over the period 1990-2008, we find that previous R&D experience is a fundamental determinant for mature and young firms, albeit to a smaller extent in the case of the YICs, suggesting that their innovation behaviour is less persistent and more erratic. Moreover, our results suggest that firm and market characteristics play a distinct role in boosting the innovation activity of firms of different age. In particular, while market concentration and the degree of product diversification are found to be important in boosting R&D activities in the sub-sample of mature firms only, YICs’ spending on R&D appears to be more sensitive to demand-pull variables, suggesting the presence of credit constraints. These results have been obtained using a recently proposed dynamic type-2 tobit estimator, which accounts for individual effects and efficiently handles the initial conditions problem.

Inequalities in Perceived Health

A report on the All-Ireland Social Capital and Health Survey. This is the first report in Ireland, North or South, which measures and identifies systematically the connections between perceived health and an extensive range of demographic and socio-economic characteristics and lifestyle behaviours. The concept of social capital and the ways in which social capital may be an important determinant of health is receiving increased attention from policy-makers. The Institute of Public Health in Ireland produced a report in 2004 based on its All Ireland Social Capital and Health Survey. The report explores how people feel about their health and highlights how this is linked with perceptions of the local social environment as well as to demographic and socio-economic circumstances and lifestyle behaviours.

Policy Credibility and Delegation to Independent Regulatory Agencies: A Comparative Empirical Analysis

Independent regulatory agencies are one of the main institutional features of the 'rising regulatory state' in Western Europe. Governments are increasingly willing to abandon their regulatory competencies and to delegate them to specialized institutions that are at least partially beyond their control. This article examines the empirical consistency of one particular explanation of this phenomenon, namely the credibility hypothesis, claiming that governments delegate powers so as to enhance the credibility of their policies. Three observable implications are derived from the general hypothesis, linking credibility and delegation to veto players, complexity and interdependence. An independence index is developed to measure agency independence, which is then used in a multivariate analysis where the impact of credibility concerns on delegation is tested. The analysis relies on an original data set comprising independence scores for thirty-three regulators. Results show that the credibility hypothesis can explain a good deal of the variation in delegation. The economic nature of regulation is a strong determinant of agency independence, but is mediated by national institutions in the form of veto players.