Effective interactions of colloids on nematic films

The elastic and capillary interactions between a pair of colloidal particles trapped on top of a nematic film are studied theoretically for large separations d. The elastic interaction is repulsive and of quadrupolar type, varying as d⁻⁵. For macroscopically thick films, the capillary interaction is likewise repulsive and proportional to d⁻⁵ as a consequence of mechanical isolation of the system comprised of the colloids and the interface. A finite film thickness introduces a nonvanishing force on the system (exerted by the substrate supporting the film) leading to logarithmically varying capillary attractions. However, their strength turns out to be too small to be of importance for the recently observed pattern formation of colloidal droplets on nematic films.

The influence of public or private paediatric health care on vaccination coverages in children in Catalonia (Spain)

BACKGROUND

Maintaining high vaccination coverages is necessary in order to control vaccine-preventable diseases. We studied vaccination coverages in a representative sample of 630 children aged <3 years in Catalonia in order to determine the relationship between vaccination coverages and socioeconomic factors.

METHODS

Sampling was carried out in a representative sample of the health regions in Catalonia stratified according to habitat. A sample of 630 parents of children aged <3 years born in October 2001 were interviewed by telephone. Information collected included sociodemographic data, type of health care provider (public or private) and information on vaccination coverage for the basic plus booster immunization series (BBI) which consisted of: four DTP, four OPV, one MMR and the doses of Hib and MenC necessary according to age of administration of the first dose.

RESULTS

A total of 87.62% of the children were vaccinated with the BBI series, and no statistically significant differences in coverage between public (87.93%) and private (88.30%) paediatric providers, or between social classes (high: 87.58%, low: 88.81%) were found. Vaccination coverage was associated with attending a day-care centre (OR: 1.89; 95% CI: 1.12-3.21) and maternal university education (OR: 1.84; 95% CI: 1.01-3.33).

CONCLUSION

Vaccination coverages are high and are similar between types of provider, probably due to preventive policies which have made a concerted effort to ensure universal vaccination.

Epidemiology of hepatitis A before and after the introduction of a universal vaccination programme in Catalonia, Spain

A universal vaccination program for preadolescents, aged 12 years, with the hepatitis A + B vaccine was introduced in 1998 in Catalonia (Spain) with the aim of protecting the whole population against hepatitis A. The hepatitis A + B vaccine program replaced the hepatitis B vaccination program for preadolescent started in 1991. The impact of the hepatitis A + B vaccination program was studied by assessment of the trend of reported cases of hepatitis A. All cases of viral hepatitis reported from 1992 to 2006 were included in the study. To evaluate changes in the epidemiology of hepatitis A, two periods were considered: a prevaccination period (1992-1998) and a post-vaccination period (2001-2006). The ratios of the rates were calculated according to age and sex. The comparison of rates and proportions was made by calculation of the normal z statistic. A total of 7536 cases of viral hepatitis were reported, of which 4109 (54.52%) were hepatitis A. The incidence rate of hepatitis A fell from 5.44 per 100 000 person-years in the prevaccination period to 3.02 in the post-vaccination period. In males, the rate fell from 6.85 to 3.89 and in females from 4.10 to 2.18. The male-female ratio of incidence rates was lower in the post-vaccination period. In males the global decline of incidence rate was 43.26% and in females 46.96%. The greatest decline occurred in the 15 to 19 years age group in both sexes (79.1% in men and 78.34% in women) but declines in the 10-14 years age group were also very important (69.21% and 67.88%, respectively). In conclusion, hepatitis A incidence fell in Catalonia in the post-vaccination period in vaccinated adolescents and also in other unvaccinated groups who have benefited from the indirect effects of the vaccination program.

Shear state of freely evolving granular gases

Hydrodynamic equations are used to identify the final state reached by a freely evolving granular gas above but close to its shear instability. The theory predicts the formation of a two bands shear state with a steady density profile. There is a modulation between temperature and density profiles as a consequence of the energy balance, the density fluctuations remaining small, without producing clustering. Moreover, the time dependence of the velocity field can be scaled out with the squared root of the average temperature of the system. The latter follows the Haff law, but with an effective cooling rate that is smaller than that of the free homogeneous state. The theoretical predictions are compared with numerical results for inelastic hard disks obtained by using the direct Monte Carlo simulation method, and a good agreement is obtained for low inelasticity.

Multipole expansion of the electrostatic interaction between charged colloids at interfaces

The general form of the electrostatic potential around an arbitrarily charged colloid at a flat interface between a dielectric and a screening phase (such as air and water, respectively) is analyzed in terms of a multipole expansion. The leading term is isotropic in the interfacial plane and varies with d(-3) where d is the in-plane distance from the colloid. The effective interaction potential between two arbitrarily charged colloids is likewise isotropic and proportional to d(-3), thus generalizing the dipole-dipole repulsion first found for point charges at water interfaces. Anisotropic attractive interaction terms can arise only for higher powers d(-n) with n > or =4. The relevance of these findings for recent experiments is discussed.

Bio-syngas production with low concentrations of CO2 and CH4 from microwave-induced pyrolysis of wet and dried sewage sludge

This paper assesses the feasibility of producing syngas from sewage sludge via two pyrolysis processes: microwave-induced pyrolysis (MWP) and conventional pyrolysis (CP). The changes in the composition of the produced gas as a function of the pyrolysis treatment and the initial moisture content of the sludge were evaluated. It was found that MWP produced a gas with a higher concentration of syngas than CP, reaching values of up to 94vol%. Moreover, this gas showed a CO2 and CH4 concentration around 50% and 70%, respectively, lower than that obtained in the gas from CP. With respect to the effect of moisture on gas composition, this was more pronounced in CP than in MWP. Thus, the presence of moisture increases the concentration of H2 and CO2 and decreases that of CO, especially when CP was used. In order to elucidate the behaviour of CO2 during the pyrolysis, the CO2 gasification kinetics of the char obtained from the pyrolysis were investigated. It was established that in microwave heating the gasification reaction is much more favoured than in conventional heating. Therefore, the low concentration of CO2 and the high concentration of CO in the microwave pyrolysis gas could be due to the self-gasification of the residue by the CO2 produced during the devolatilization of the sewage sludge in the pyrolysis process.

Characterization of the Yarrowia lipolytica YlSRP72 gene, a component of the yeast signal recognition particle

The Yarrowia lipolytica SRP72 gene product (YlSRP72), a homolog of the 72-kDa subunit of the mammalian SRP, encodes a putative protein of 602 amino acids. Northern blot analysis revealed a unique YlSRP72-specific transcript of 1.8 kb. The deduced amino acid sequence showed higher identities with the Srp72 proteins of euascomycetes than with hemiascomycetes. Chromosomal hybridization experiments showed that the YlSRP72 gene is located in chromosome V of the standard E150 strain of Y. lipolytica. Fluorescent microscopy revealed that the YlSRP72-GFP fusion protein was expressed in the cytoplasm and nucleus. The YlSRP72 gene was interrupted by the pop-out method; however, deletion of the gene proved to be lethal. This is in contrast to the results described for the Saccharomyces cerevisiae SRP72 gene, which is not essential for cell growth, and supports our previous finding with another component of the yeast recognition particle, YlSEC65. The present work suggests that SRP-dependent targeting is the main secretory pathway in Y. lipolytica, as has been described for higher eukaryotes.

Proteomic analysis reveals metabolic changes during yeast to hypha transition in Yarrowia lipolytica

Fungal dimorphism is important for survival in different environments and has been related to virulence. The ascomycete Yarrowia lipolytica can grow as yeast, pseudomycelial or mycelial forms. We have used a Y. lipolytica parental strain and a Deltahoy1 mutant, which is unable to form hypha, to set up a model for dimorphism and to characterize in more depth the yeast to hypha transition by proteomic techniques. A two-dimensional gel electrophoresis (2-DE) based differential expression analysis of Y. lipolytica yeast and hyphal cells was performed, and 45 differentially expressed proteins were detected; nine with decreased expression in hyphal cells were identified. They corresponded to the S. cerevisiae homologues of Imd4p, Pdx3p, Cdc19, Sse1p, Sol3p, Sod2p, Xpt1p, Mdh1p and to the unknown protein YALIOB00924g. Remarkably, most of these proteins are involved in metabolic pathways, with four showing oxidoreductase activity. Furthermore, taking into account that this is the first report of 2-DE analysis of Y. lipolytica protein extracts, 35 more proteins from the 2D map of soluble yeast proteins, which were involved in metabolism, cell rescue, energy and protein synthesis, were identified.

Nosocomial spread of Pseudomonas aeruginosa producing the metallo-β-lactamase VIM-2 in a Spanish hospital: clinical and epidemiological implications

Thirty-four isolates of pan-resistant Pseudomonas aeruginosa producing VIM-2 metallo-beta-lactamase (MBL) were detected at a university hospital in Spain (July 2004-September 2006). Eleven (32%) patients had clinically significant infections, and three (27%) of these patients died. A single clone of MBL-producing P. aeruginosa was identified by pulsed-field gel electrophoresis. A cluster of isolates associated with the vascular surgery ward involved ten patients and appeared as a series of low-grade, sustained and misdiagnosed endemic infections in the hospital. The identification of MBL-positive P. aeruginosa should be considered mandatory in the surveillance of pan-resistant P. aeruginosa and requires a high index of suspicion in the context of endemic infections with a low attack rate.

Immobilizing Cu,Zn-superoxide dismutase in hydrogels of carboxymethylcellulose improves its stability and wound healing properties

Hydrogels of carboxymethylcellulose (CMC) with 50 and 90% cross-linking degree (CMC50% and CMC90%, respectively) were prepared and loaded with bovine erythrocyte Cu,Zn-superoxide dismutase (SOD) to obtain two drug delivery systems: SOD-CMC50% and SOD-CMC90%. Resistance of native SOD to inactivation by H2O2 and the effect of applying SOD-CMC hydrogels to open wounds of rats' back skin were examined and compared to that of SOD trapped into CMC50% and CMC90% hydrogels. Also, the effect of CMC50% and SOD-CMC90% on human fibroblasts proliferation was evaluated at different times. It was found that SOD in the hydrogel was more resistant to H2O2 inactivation than the native enzyme and at the same time it reduced the time necessary for wound healing. Furthermore, the highest cell proliferation value was found for the CMC50% hydrogels, which had a three-dimensional structure suitable for gas and nutrient exchanges and improving cell life conditions.

Treatment of chronic he1patitis C genotype 1 with peginterferon-alpha2a (40 kDa) plus ribavirin under routine clinical practice in Spain: early prediction of sustained virological response rate

BACKGROUND

Sustained virological response rates of up to 52% have been obtained with peginterferon alpha2a (40 kDa) plus ribavirin in patients suffering from chronic hepatitis C genotype 1 in randomized-controlled trials.

AIM

To assess early virological response and its clinical utility in predicting an sustained virological response in patients suffering from chronic hepatitis C genotype 1 in routine clinical practice in Spain.

METHODS

Treatment-naïve patients received pegylated interferon alpha2a (40 kDa) 180 microg/week plus ribavirin 1000/1200 mg/day for 48 weeks, and were followed for a further 24 weeks. Overall, 475 patients received at least one dose of medication and were included in the efficacy population.

RESULTS

The overall sustained virological response rate was 48%. Of those with week 12 virological data, 83% had an early virological response. The negative predictive value of an early virological response was 93%.

CONCLUSION

If sustained virological response is the goal, a treatment-decision based on a 12-week evaluation during routine clinical practice is feasible.

Treatment of chronic he1patitis C genotype 1 with peginterferon-alpha2a (40 kDa) plus ribavirin under routine clinical practice in Spain: early prediction of sustained virological response rate

BACKGROUND

Sustained virological response rates of up to 52% have been obtained with peginterferon alpha2a (40 kDa) plus ribavirin in patients suffering from chronic hepatitis C genotype 1 in randomized-controlled trials.

AIM

To assess early virological response and its clinical utility in predicting an sustained virological response in patients suffering from chronic hepatitis C genotype 1 in routine clinical practice in Spain.

METHODS

Treatment-naïve patients received pegylated interferon alpha2a (40 kDa) 180 microg/week plus ribavirin 1000/1200 mg/day for 48 weeks, and were followed for a further 24 weeks. Overall, 475 patients received at least one dose of medication and were included in the efficacy population.

RESULTS

The overall sustained virological response rate was 48%. Of those with week 12 virological data, 83% had an early virological response. The negative predictive value of an early virological response was 93%.

CONCLUSION

If sustained virological response is the goal, a treatment-decision based on a 12-week evaluation during routine clinical practice is feasible.

Vaccination coverage in indigenous and immigrant children under 3 years of age in Catalonia (Spain)

Vaccination coverage in a representative sample of children under 3 years of age in Catalonia (Spain) was studied. Parents of children selected were contacted and asked for the child's vaccination card. A total of 630 children were included, of whom 570 were indigenous and 60 immigrants. Primary vaccination coverage was 96.5% for indigenous and 85% for immigrant children (p=0.0001), while the coverage of primary vaccination plus booster doses was 88.6% in indigenous and 78.3% in immigrant children (p=0.02). Efforts should be made to increase primary vaccination coverage in immigrant children and booster dose coverage in both indigenous and immigrant children.

[Excess mortality due to tuberculosis and factors associated to death in and annual cohort of patients diagnosed of tuberculosis]

OBJECTIVE

To calculate excess mortality in an annual cohort of tuberculosis patients and study the factors associated with death.

MATERIAL AND METHOD

Cases of tuberculosis reported in Catalonia (May 1996-April 1997). Patients were classified as completed treatment/cured (compliant), non-compliant, failures, transfers out and deaths. Excess mortality was defined as the ratio actual deaths/expected deaths (according to general mortality figures for Catalonia, May 1996-April 1997). Factors associated with death were determined by a comparative study of variables (demographic, substance abuse, comorbidity, tuberculosis-related disease) in deaths after diagnosis and survivors. Time from diagnosis to death was recorded.

RESULTS

Patients included: 2,085. Patients classified as: completed treatment/cured (compliant), 1,406 (67.43 %); noncompliant, 165 (7, 91%); failures, 5 (0.24%); transfers out, 25 (1.21%); deaths, 133 (6.38%), 28 of which occurred before diagnosis and 105 after diagnosis. Insufficient data in medical record for classification, 351 (16.83%) patients. Excess mortality: 5.98 (95% CI: 4.96-7.0). Factors associated with death: treatment with non-standardized guidelines, 46%; OR: 10.3 (6.2-17.4); HIV infection, 40%; OR: 13.0 (6.6-25.8); age greater than 64 years, 40%; OR: 14.6 (3.0-69.8); alcoholism, 25%; OR: 2.0 (1.1-3.6); neoplasm, 16%; OR: 3.9 (1.8-8.6; renal failure, 8%; OR: 10.1 (3.1-32.3). The shortest time from diagnosis to death was in patients with only one risk factor, except for HIV infection, where the time passed was the longest observed.

CONCLUSIONS

We found substantial excess mortality in tuberculosis patients. Death was associated with the efficacy of treatment, HIV coinfection, advanced age, alcoholism and the coexistence of neoplasms or renal failure.

Absence of port-site metastases following staging laparoscopy for gastric carcinoma

BACKGROUND

port-site metastases (PSM) have been reported following oncological laparoscopic surgery. However, their frequency after laparoscopic examination in gastric cancer has not been well established.

MATERIAL AND METHODS

prospective follow-up of 41 patients having had a staging laparoscopy and a follow-up longer than 12 months. Mean age was 65 years (29-89). After staging, an open gastrectomy was performed in 33 cases. Mean follow-up was 21.4 (12-66) months. PSM was defined as a node in the former port-site wound with adenocarcinoma histology at biopsy.

RESULTS

no patient showed clinical signs of PSM or port-site recurrence, even in advanced stages. We had no morbidity or postoperative mortality attributable to laparoscopic manoeuvres, and no need for laparotomy in cases without a gastrectomy indication.

CONCLUSIONS

our results suggest that staging laparoscopy is a safe procedure in gastric carcinoma, as it is not associated with PSM after even considerable follow-up, and has a very low complication rate.

Community outbreak of Legionnaires’ disease in Vic-Gurb, Spain in October and November 2005

This paper reports the investigation of a community-acquired outbreak of Legionnaires'; disease in the municipalities of Vic and Gurb (Central Region of Catalonia, Spain). There were 55 cases reported in October and November 2005. An epidemiological and environmental investigation was undertaken. Thirty-five case patients (64%) lived in Vic or Gurb, while 36% had visited or worked in Vic or Gurb during the 10 days before onset of symptoms, but no commonly frequented building could be identified. Water probes for culture were obtained from 30 cooling towers. In five cooling towers of two industrial settings in Gurb (plants A and B), Legionella pneumophila (Lp) serogroup 1 was present. Two Lp-1 strains were recovered from cooling towers in plants A and B. The Lp-1 strain from plant A showed a PGFE profile identical with those obtained from three patients. The exposure to Legionella pneumophila apparently occurred in a large area, since 43 of the 55 cases lived, visited or worked within a distance of 1,800 m from plant A, and six cases in a distance between 2,500 and 3,400 m. The inspections of cooling towers in plant A revealed inadequate disinfectant doses of biocide, non-existent maintenance records on weekends and wrong sample points for routine microbial check-ups. Weather conditions in October 2005 template temperature and high humidity (wind conditions are unappreciable) could have been favourable factors in this outbreak together with the flat terrain of Gurb and Vic area, explaining the extensive horizontal airborne dissemination of contaminated aerosols. The outbreak could have been prevented by proper and correct maintenance of the cooling tower at plant A.

Community outbreak of Legionnaires disease in Vic-Gurb, Spain in October and November 2005

This paper reports the investigation of a community-acquired outbreak of Legionnaires' disease in the municipalities of Vic and Gurb (Central Region of Catalonia, Spain). There were 55 cases reported in October and November 2005. An epidemiological and environmental investigation was undertaken. Thirty-five case patients (64%) lived in Vic or Gurb, while 36% had visited or worked in Vic or Gurb during the 10 days before onset of symptoms, but no commonly frequented building could be identified. Water probes for culture were obtained from 30 cooling towers. In five cooling towers of two industrial settings in Gurb (plants A and B), Legionella pneumophila (Lp) serogroup 1 was present. Two Lp-1 strains were recovered from cooling towers in plants A and B. The Lp-1 strain from plant A showed a PGFE profile identical with those obtained from three patients. The exposure to Legionella pneumophila apparently occurred in a large area, since 43 of the 55 cases lived, visited or worked within a distance of 1,800 m from plant A, and six cases in a distance between 2,500 and 3,400 m. The inspections of cooling towers in plant A revealed inadequate disinfectant doses of biocide, non-existent maintenance records on weekends and wrong sample points for routine microbial check-ups. Weather conditions in October 2005 template temperature and high humidity (wind conditions are unappreciable) could have been favourable factors in this outbreak together with the flat terrain of Gurb and Vic area, explaining the extensive horizontal airborne dissemination of contaminated aerosols. The outbreak could have been prevented by proper and correct maintenance of the cooling tower at plant A.

[Disassociation between agrammatic and anomic patients in their production of verb forms]

INTRODUCTION

Electrophysiological and neuroimaging studies suggest that regular and irregular verbs are differently represented in the brain. Findings from studies of patients seem to agree with this view, but there are discordant data.

AIM

To test if there is a dissociation in regular and irregular verb processing between patients with anterior lesions, characterized as Broca's aphasics, and patients with posterior lesions, characterized as anomics.

PATIENTS AND METHODS

10 aphasic patients participated in the study: five presenting evidence of Broca's aphasia and five presenting evidence of anomia. The task required patients to complete 58 sentences with a verb conjugated in the past tense form. 29 sentences required an irregular verb and 29 required a regular verb.

RESULTS

Statistical analyses indicate a main effect due to differences between the different types of patients, and an interaction between this effect of patient type and the effect of verb type. The interaction was due to the fact that anomic patients had more difficulty in completing sentences using irregular verbs.

CONCLUSIONS

The results of this study support a dual route model, which assumes that regular verbs are processed by application of morphological rules whereas irregular verbs are processed through the addressed recovery of conjugated forms.

Cost-effectiveness analysis of inactivated virosomal subunit influenza vaccination in children aged 3-14 years from the provider and societal perspectives

The costs and benefits of vaccinating a theoretical cohort of 1000 preschool and school age children (3-14 years) with one dose of inactivated virosomal subunit influenza vaccine in primary health care centers of the Catalan Health Service during the fall annual health examination were compared with the current strategy of no routine vaccination. The economic analysis was carried out from the provider perspective (cost-effectiveness analysis) and from the societal perspective (cost-effectiveness and cost-benefit analysis). The time horizon of the study was established at 6 months. In the base case (cost of vaccination of euro 9.425, cost of paediatric visit plus antibiotic and antipyretic treatment of euro 42.50, cost of 1 day of hospital stay of euro 454.25, cost of the work lost by the mother to take care of her ill child of euro 29.2 and cost of 1 year of quality adjusted life year lost of euro 10,662), the vaccination does not save money from the provider perspective (net present value=euro-1460.51), but the cost-effectiveness ratios are very reasonable (euro 5.80 per episode of acute febrile respiratory process avoided and euro 18.26 per quality adjusted life year saved). From the societal perspective, the vaccination saves money (net present value=euro+7587.03) and the benefit-cost ratio is 1.80, meaning that euro 0.80 is saved per euro invested. Our study shows that vaccination of children 3-14 years old with a single dose of inactivated subunit influenza vaccine in primary health care centers during the fall annual health examination provides socioeconomic benefits to the society in addition to substantial health benefits for the child.

The seroepidemiology of tetanus in Catalonia, Spain

Titres of anti-tetanus toxin antibodies > or = 0.1 IU/ml were determined using an enzyme linked immunosorbent assay in representative samples of the juvenile and adult population of Catalonia. The prevalence obtained in 1,316 juveniles and 1,296 adults was 99.4 and 68.3%, respectively. In adults, the prevalence in males (76.5%) was higher (P < 0.001) than in females (61.7%), fell with increasing age and was higher in subjects born in Catalonia (72.5%) than in those born outside Catalonia (57.9%) (P < 0.001). These results show that routine vaccination of children is successful. In adults aged > or = 45 years, the prevalence is inadequate and efforts should be made to increase vaccination.