The impact of social relationships on the maintenance of independence in advanced old age: findings of a Swiss Longitudinal Study .

The impact of social relationships on the maintenance of independence over periods of 12-18 months in a group of 306 octogenarians is assessed in this study. The study is based on the results of the Swilsoo (Swiss Interdisciplinary Longitudinal Study on the Oldest Old). Participants (80-84 years old at baseline) were interviewed five times between 1994 and 1999. Independence was defined as the capacity to perform without assistance eight activities of daily living. We distinguished in our analyses kinship and friendship networks and evaluated social relationships with the help of a series of variables serving as indicators of network composition and contact frequency. Logistic regression models were used to identify the short-term effects of social relationships on independence, after controlling for sociodemographic and health-related variables; independence at a given wave of interviews was interpreted in the light of social factors measured at the previous wave. Our analyses indicate that the existence of a close friend has a significant impact on the maintenance of independence (OR=1.58, p<0.05), which is not the case with the other variables concerning network composition. Kinship contacts were also observed to have a positive impact on independence (OR=1.12, p<0.01).

A deterministic model to assess the impact of AIDS interventions in countries with generalized HIV epidemic. An application to Botswana

General introductionThe Human Immunodeficiency/Acquired Immunodeficiency Syndrome (HIV/AIDS) epidemic, despite recent encouraging announcements by the World Health Organization (WHO) is still today one of the world's major health care challenges.The present work lies in the field of health care management, in particular, we aim to evaluate the behavioural and non-behavioural interventions against HIV/AIDS in developing countries through a deterministic simulation model, both in human and economic terms. We will focus on assessing the effectiveness of the antiretroviral therapies (ART) in heterosexual populations living in lesser developed countries where the epidemic has generalized (formerly defined by the WHO as type II countries). The model is calibrated using Botswana as a case study, however our model can be adapted to other countries with similar transmission dynamics.The first part of this thesis consists of reviewing the main mathematical concepts describing the transmission of infectious agents in general but with a focus on human immunodeficiency virus (HIV) transmission. We also review deterministic models assessing HIV interventions with a focus on models aimed at African countries. This review helps us to recognize the need for a generic model and allows us to define a typical structure of such a generic deterministic model.The second part describes the main feed-back loops underlying the dynamics of HIV transmission. These loops represent the foundation of our model. This part also provides a detailed description of the model, including the various infected and non-infected population groups, the type of sexual relationships, the infection matrices, important factors impacting HIV transmission such as condom use, other sexually transmitted diseases (STD) and male circumcision. We also included in the model a dynamic life expectancy calculator which, to our knowledge, is a unique feature allowing more realistic cost-efficiency calculations. Various intervention scenarios are evaluated using the model, each of them including ART in combination with other interventions, namely: circumcision, campaigns aimed at behavioral change (Abstain, Be faithful or use Condoms also named ABC campaigns), and treatment of other STD. A cost efficiency analysis (CEA) is performed for each scenario. The CEA consists of measuring the cost per disability-adjusted life year (DALY) averted. This part also describes the model calibration and validation, including a sensitivity analysis.The third part reports the results and discusses the model limitations. In particular, we argue that the combination of ART and ABC campaigns and ART and treatment of other STDs are the most cost-efficient interventions through 2020. The main model limitations include modeling the complexity of sexual relationships, omission of international migration and ignoring variability in infectiousness according to the AIDS stage.The fourth part reviews the major contributions of the thesis and discusses model generalizability and flexibility. Finally, we conclude that by selecting the adequate interventions mix, policy makers can significantly reduce the adult prevalence in Botswana in the coming twenty years providing the country and its donors can bear the cost involved.Part I: Context and literature reviewIn this section, after a brief introduction to the general literature we focus in section two on the key mathematical concepts describing the transmission of infectious agents in general with a focus on HIV transmission. Section three provides a description of HIV policy models, with a focus on deterministic models. This leads us in section four to envision the need for a generic deterministic HIV policy model and briefly describe the structure of such a generic model applicable to countries with generalized HIV/AIDS epidemic, also defined as pattern II countries by the WHO.

Impact of HSD11B1 polymorphisms on BMI and components of the metabolic syndrome in patients receiving psychotropic treatments.

BACKGROUND: Metabolic syndrome (MetS) associated with psychiatric disorders and psychotropic treatments represents a major health issue. 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) is an enzyme that catalyzes tissue regeneration of active cortisol from cortisone. Elevated enzymatic activity of 11β-HSD1 may lead to the development of MetS. METHODS: We investigated the association between seven HSD11B1 gene (encoding 11β-HSD1) polymorphisms and BMI and MetS components in a psychiatric sample treated with potential weight gain-inducing psychotropic drugs (n=478). The polymorphisms that survived Bonferroni correction were analyzed in two independent psychiatric samples (nR1=168, nR2=188) and in several large population-based samples (n1=5338; n2=123 865; n3>100 000). RESULTS: HSD11B1 rs846910-A, rs375319-A, and rs4844488-G allele carriers were found to be associated with lower BMI, waist circumference, and diastolic blood pressure compared with the reference genotype (Pcorrected<0.05). These associations were exclusively detected in women (n=257) with more than 3.1 kg/m, 7.5 cm, and 4.2 mmHg lower BMI, waist circumference, and diastolic blood pressure, respectively, in rs846910-A, rs375319-A, and rs4844488-G allele carriers compared with noncarriers (Pcorrected<0.05). Conversely, carriers of the rs846906-T allele had significantly higher waist circumference and triglycerides and lower high-density lipoprotein-cholesterol exclusively in men (Pcorrected=0.028). The rs846906-T allele was also associated with a higher risk of MetS at 3 months of follow-up (odds ratio: 3.31, 95% confidence interval: 1.53-7.17, Pcorrected=0.014). No association was observed between HSD11B1 polymorphisms and BMI and MetS components in the population-based samples. CONCLUSIONS: Our results indicate that HSD11B1 polymorphisms may contribute toward the development of MetS in psychiatric patients treated with potential weight gain-inducing psychotropic drugs, but do not play a significant role in the general population.

Impact of anti-T cell therapy in the immunogenicity of seasonal influenza vaccine in kidney transplants recipients

1. Mise en perspective de l'étude La grippe est une cause importante de morbidité et de mortalité après la transplantation d'organe. Bien que la principale stratégie de prévention de la grippe après la transplantation d'organes soit l'administration du vaccin antigrippal annuel, l'immunogénicité de ce vaccin chez les greffés d'organe n'est pas optimale. Nous avons effectué une étude prospective pour évaluer l'influence de la thérapie d'induction sur l'immunogénicité du vaccin de la grippe. 2. Méthodes Nous avons comparé la réponse au vaccin de la grippe chez deux groupes de greffés rénaux en fonction de la thérapie d'induction reçu (thymoglobulin vs basiliximab). Le taux des anticorps ont étés mesurés par inhibition de l'hémagglutination (HI). La réponse au vaccin (taux de séroconversion) a été définie comme l'augmentation > 4 fois du taux d'anticorps (immunoglobulines) et ceci a été notre outcome primaire. 3. Résultats Soixante transplantés rénaux ont été inclus dans l'étude (thymoglobuline=22, basiliximab=38). Les patients dans le group traité par thymoglobuline étaient plus âgés (p=0.16), avaient des valeurs de créatinine plus élevés (p=0.16) et avaient étés transplanté auparavant (p=0.02). Aucune différence n'a été mise en évidence au niveau de taux des immunoglobulines pour les 3 souches virales entre les 2 groupes (p=0.69 pour H INI, p=0.56 pour H3N2, p=0.7 pour Influenza Β). Le taux de séroconversion à au moins une souche virale a été de 68 % pour le groupe thymoglobuline et de 73% pour le groupe basiliximab (p=0.77). 4. Conclusion Aucune différence significative n'a été démontré dans l'immunogénicité du vaccin de la grippe dans les transplantés rénaux ayant reçu soit du thymoglobuline soit du basiliximab comme traitement d'induction.

Impact of moisture on survival of Aedes aegypti eggs and ovicidal activity of Metarhizium anisopliae under laboratory conditions

The effect of relative humidity (43%, 75%, 86% and > 98%) on Aedes aegypti eggs treated with Metarhizium anisopliae or water only was tested for up to a six months exposure at 25ºC. Survival of larvae inside eggs was clearly affected by the lowest humidity (43%) tested, and eclosion diminished at all humidities after increasing periods of exposure. M. anisopliae showed to have a strong ovicidal activity only at humidity close to saturation. No difference of activity was found between conidia and hyphal bodies tested. This fungus affected larvae inside eggs and has potential as a control agent of this important vector in breeding sites with high moisture.

Impact of standardised review of intravenous antibiotic therapy 72 hours after prescription in two internal medicine wards.

Post-prescription review of hospital antibiotic therapy may contribute to more appropriate use. We estimated the impact of a standardised review of intravenous antibiotic therapy three days after prescription in two internal medicine wards of a university hospital. In one ward, we assessed the charts of patients under intravenous antibiotic therapy using a standardised review process and provided feedback to the prescriber. There was no intervention in the other ward. After six months we crossed the allocation between the two wards. In all, 204 courses of antibiotic therapy were included in the intervention periods and 226 in the control periods. Post-prescription review led to proposals for modification in 46% of antibiotic courses. Time to treatment modification was 22% shorter in the intervention periods compared with the control periods (3.9+/-5.2 days vs 5.0+/-6.0 days, P=0.007). Patients included in the intervention group had lower antibiotic consumption than patients in the control group, but the intervention had no significant impact on the overall antibiotic consumption of the two wards.

Long-Term Control of Endemic Hospital-Wide Methicillin-Resistant Staphylococcus aureus (MRSA): The Impact of Targeted Active Surveillance for MRSA in Patients and Healthcare Workers

To evaluate the long-term impact of successive interventions on rates of methicillin-resistant Staphylococcus aureus (MRSA) colonization or infection and MRSA bacteremia in an endemic hospital-wide situation. DESIGN:Quasi-experimental, interrupted time-series analysis. The impact of the interventions was analyzed by use of segmented regression. Representative MRSA isolates were typed by use of pulsed-field gel electrophoresis. SETTING:A 950-bed teaching hospital in Seville, Spain. PATIENTS:All patients admitted to the hospital during the period from 1995 through 2008. METHODS:Three successive interventions were studied: (1) contact precautions, with no active surveillance for MRSA; (2) targeted active surveillance for MRSA in patients and healthcare workers in specific wards, prioritized according to clinical epidemiology data; and (3) targeted active surveillance for MRSA in patients admitted from other medical centers. RESULTS:Neither the preintervention rate of MRSA colonization or infection (0.56 cases per 1,000 patient-days [95% confidence interval {CI}, 0.49-0.62 cases per 1,000 patient-days]) nor the slope for the rate of MRSA colonization or infection changed significantly after the first intervention. The rate decreased significantly to 0.28 cases per 1,000 patient-days (95% CI, 0.17-0.40 cases per 1,000 patient-days) after the second intervention and to 0.07 cases per 1,000 patient-days (95% CI, 0.06-0.08 cases per 1,000 patient-days) after the third intervention, and the rate remained at a similar level for 8 years. The MRSA bacteremia rate decreased by 80%, whereas the rate of bacteremia due to methicillin-susceptible S. aureus did not change. Eighty-three percent of the MRSA isolates identified were clonally related. All MRSA isolates obtained from healthcare workers were clonally related to those recovered from patients who were in their care. CONCLUSION:Our data indicate that long-term control of endemic MRSA is feasible in tertiary care centers. The use of targeted active surveillance for MRSA in patients and healthcare workers in specific wards (identified by means of analysis of clinical epidemiology data) and the use of decolonization were key to the success of the program.

Evaluating the probability and the impact of a failure in GMPLS based networks

In this paper, we define a new scheme to develop and evaluate protection strategies for building reliable GMPLS networks. This is based on what we have called the network protection degree (NPD). The NPD consists of an a priori evaluation, the failure sensibility degree (FSD), which provides the failure probability, and an a posteriori evaluation, the failure impact degree (FID), which determines the impact on the network in case of failure, in terms of packet loss and recovery time. Having mathematical formulated these components, experimental results demonstrate the benefits of the utilization of the NPD, when used to enhance some current QoS routing algorithms in order to offer a certain degree of protection

Impact of water renewal on the residual effect of larvicides in the control of Aedes aegypti

This study was carried out to evaluate the residual effect of three larvicides under laboratory conditions for 100 days in Aedes aegypti. The larval mortality rate was measured without water renewal or with daily water renewal (80%). With temephos, there was 100% mortality in both groups until the 70th day. In the Bacillus thuringiensis israelensis (Bti)-WDG test, there was no difference during the first 20 days. With Bti-G, without water renewal, mortality was sustained above 90% for up to 35 days. The second experiment (with water renewal) reduced the mortality to below 90% after the first 20 days. When renewed water was provided, the residual effect was significantly lower for all larvicides.

Municipal distribution of bladder cancer mortality in Spain: Possible role of mining and industry

BACKGROUND Spain shows the highest bladder cancer incidence rates in men among European countries. The most important risk factors are tobacco smoking and occupational exposure to a range of different chemical substances, such as aromatic amines. METHODS This paper describes the municipal distribution of bladder cancer mortality and attempts to "adjust" this spatial pattern for the prevalence of smokers, using the autoregressive spatial model proposed by Besag, York and Molliè, with relative risk of lung cancer mortality as a surrogate. RESULTS It has been possible to compile and ascertain the posterior distribution of relative risk for bladder cancer adjusted for lung cancer mortality, on the basis of a single Bayesian spatial model covering all of Spain's 8077 towns. Maps were plotted depicting smoothed relative risk (RR) estimates, and the distribution of the posterior probability of RR>1 by sex. Towns that registered the highest relative risks for both sexes were mostly located in the Provinces of Cadiz, Seville, Huelva, Barcelona and Almería. The highest-risk area in Barcelona Province corresponded to very specific municipal areas in the Bages district, e.g., Suría, Sallent, Balsareny, Manresa and Cardona. CONCLUSION Mining/industrial pollution and the risk entailed in certain occupational exposures could in part be dictating the pattern of municipal bladder cancer mortality in Spain. Population exposure to arsenic is a matter that calls for attention. It would be of great interest if the relationship between the chemical quality of drinking water and the frequency of bladder cancer could be studied.

Impact of severe epilepsy on development: Recovery potential after successful early epilepsy surgery.

Purpose: Epilepsy surgery in young children with focal lesions offers a unique opportunity to study the impact of severe seizures on cognitive development during a period of maximal brain plasticity, if immediate control can be obtained. We studied 11 children with early refractory epilepsy (median onset, 7.5 months) due to focal lesion who were rendered seizure-free after surgery performed before the age of 6 years. Methods: The children were followed prospectively for a median of 5 years with serial neuropsychological assessments correlated with electroencephalography (EEG) and surgery-related variables. Results: Short-term follow-up revealed rapid cognitive gains corresponding to cessation of intense and propagated epileptic activity [two with early catastrophic epilepsy; two with regression and continuous spike-waves during sleep (CSWS) or frontal seizures]; unchanged or slowed velocity of progress in six children (five with complex partial seizures and frontal or temporal cortical malformations). Longer-term follow-up showed stabilization of cognitive levels in the impaired range in most children and slow progress up to borderline level in two with initial gains. Discussion: Cessation of epileptic activity after early surgery can be followed by substantial cognitive gains, but not in all children. In the short term, lack of catch-up may be explained by loss of retained function in the removed epileptogenic area; in the longer term, by decreased intellectual potential of genetic origin, irreversible epileptic damage to neural networks supporting cognitive functions, or reorganization plasticity after early focal lesions. Cognitive recovery has to be considered as a "bonus," which can be predicted in some specific circumstances.