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SUMMARY Salmonella enterica has more than 2,500 different serovars that have been described as causes of human infections, and S. enterica serovar Enteritidis is the most prevalent of these serovars. In some regions in Brazil, S. enterica serovar Minnesota was prevalent in 37.93% of broiler samples. This study evaluated the effect of a prebiotic (PREB) based on mannan oligosaccharide on the immune response of broilers challenged against Salmonella Enteritidis (SE) or Minnesota (SM). PREB supplementation increased the weight gain and reduced Salmonella recovered and mRNA gene expression of IL12 in livers of SE-challenged broilers, but did not prevent colonization by SM in the liver at 16 h after challenge. At the time of challenge, birds supplemented with PREB had higher lymphocyte scores in the lamina propria, villi edema, and dilation, suggesting an inflammatory reaction when compared to a non-supplemented group. PREB supplementation could prevent SE colonization in the livers of broilers 16 h after challenge; however, it would have no effect on SM challenged birds. The challenge with serovar Enteritidis induces higher IL12 mRNA expression levels than challenge with SM.

This study was conducted to evaluate the effects of a blend of organic acids (OAs) in diets with or without antibiotic growth promoter (AGP) in chickens challenged with Clostridium perfringens. Day-old male broiler chicks were used in a trial with 4 treatments and 6 replicates of 50 birds per pen, for 43 days, in a completely randomized design. The treatments in a 2×2 factorial arrangement consisted of the presence or absence of enramycin (AGP) and of a blend of OA in the feed. All birds were inoculated at 7 days of age with an anticoccidial vaccine in the drinking water; on days 14, 15, and 16, they were inoculated with C. perfringens in the feed. OA improved weight gain, body weight, and feed intake in the periods 1–7 days and 1–21 days in chicks without antibiotic supplementation. The AGP had the main effect of increasing weight gain and body weight at 35 d; the OA increased weight gain, body weight, and feed intake at 43 days of age. The birds supplemented with OA without AGP had a higher number of CD3+ cells in the ileum mucosa and lower crypt depth than birds supplemented with both OA and antibiotic at 7 days. At 21 days of age, birds fed OA without AGP had higher villus height and a larger villus/crypt ratio; however, there were no differences in the CD3+ cells in the ileal mucosa. The use of OA was beneficial for weight gain and AGP for feed conversion, and the combination of OA and AGP brings complementary advantages in production.

SUMMARY Salmonellosis is one of the most common worldwide zoonosis, and the Enteritidis and Typhimurium serotypes are most prevalent. In this study, we evaluated the effects of a diet supplemented with mannanoligosaccharides (MOS) on CD3+ ,C D4+ ,C D8+, and goblet cell counts in the intestines of broilers vaccinated and challenged with Salmonella Enteritidis. The evaluation was based on randomized experiments including 45 chickens divided into 3 experimental groups. Group 1 received a nonsupplemented control diet. Group 2 received a diet supplemented with 1 kg MOS/t from d 1 to 21 and 0.5 kg MOS/t from d 22 to 56. Group 3 received a diet supplemented with 2 kg MOS/t from d 1 to 21 and 1 kg MOS/t from d 22 to 56. Chickens fed the lower level of MOS demonstrated reduced fecal shedding of Salmonella 14 d after being challenged (P < 0.05). Both groups of MOS-supplemented chickens showed an increase in CD4+ and CD8+ cell counts in the ileal and cecal mucosa after being challenged with Salmonella Enteritidis (SE). Supplementation with MOS increased the specific T lymphocyte infiltration in the intestinal mucosa of chickens vaccinated and challenged with Salmonella Enteritidis.

The aim of the present evaluation was to assess the efficacy of blends of organic acids and oregano extracts supplied from d 1 to 21 and from d 35 to 42 in feed, drinking water, or both, in controllingSalmonella Enteritidis persistence in the crop and ceca of broiler chicken. A total of 105 one-day-old male broiler breeder chicks were randomly distributed into 5 different treatments according to the supply of referred blends andSalmonella Enteritidis challenge.Salmonella Enteritidis was inoculated directly in the crop of birds at the 15 d of age. Treatments were unsupplemented unchallenged, unsupplemented challenged, supplemented through water and challenged, supplemented through feed and challenged, and supplemented through feed and water and challenged. Use of the additives in feed and water and in water alone efficiently controlledSalmonella shedding and reduced cecal persistence. Immune mechanisms involved are proposed.

Vários fatores negativos podem afetar a saúde intestinal de frangos de corte e reduzir o seu desempenho. Aditivos para alimentação animal, chamados melhoradores de crescimento são utilizados na produção de frangos para controlar os problemas intestinais. Entretanto, a dificuldade de se induzir enterites em condições experimentais torna difícil a avaliação destes produtos. O objetivo deste estudo foi avaliar o melhor modelo experimental para induzir enterite em frangos de corte. Foram utilizados 192 pintinhos de corte, machos (Cobb 500®), divididos em esquema fatorial 2x4 (com boa ou baixa qualidade do óleo na dieta e com ou sem vacina contra coccidiose e doença de Gumboro), com oito tratamentos. As aves foram alojadas em cama de maravalha, com água e ração à vontade, e foram pesadas semanalmente. Nos dias 14, 21, 28 e 35, seis aves por tratamento foram abatidas para avaliação de lesões macroscópicas e microscópicas mediante a implementação de um sistema padrão de classificação de severidade das lesões que considerou infiltração linfocítica, morfologia dos enterócitos, edema intersticial e dilatação dos vasos linfáticos na mucosa do intestino. Foi observado que frangos alimentados com gordura de baixa qualidade na ração apresentaram menor ganho de peso e maior severidade de lesões histológicas em todos os segmentos intestinais. Estas lesões foram mais severas em aves desafiadas com coccidiose e doença de Gumboro. Estes resultados sugerem que a inclusão de gordura de baixa qualidade na ração, associada ao desafio com cocciciose no primeiro dia de vida e contra doença de Gumboro no 16º dia, é o melhor protocolo para induzir enterite em frangos de corte em condições experimentais, e ainda que o sistema padrão de classificação de severidade de lesões intestinais foi adequado para avaliar as enterites em frangos de corte. Several negative conditions affect broilers intestinal health and reduce their performance. Feed additives, called growth promoters, are used in broilers production to control enteric problems, but is very difficult to evaluate these products in experimental conditions. The aim of this study was to evaluate the best experimental model to induce enteritis in broilers. A 192 one-day-old male broilers (Cobb 500®) were divided into 2x4 a factorial design (with good or poor quality oil in diet and with or without coccidiosis and Gumboro disease vaccine), with eight treatments. The birds were housed on litter, with water and feed ad libitum and were weighed weekly. At days 14, 21, 28 and 35, six birds per treatment were euthanized and gut gross lesions evaluated. Samples of duodenum, jejunum and ileum were taken for histopathological evaluation. A standard lesion score considering lymphocytic infiltration, enterocytes morphology, interstitial edema, and lymph vessel dilation was used. It was observed that broilers fed with poor quality of oil in the diet showed lower body weight and more severe macroscopic and histopathologic lesions on all intestinal segments. These lesions were more severe in birds challenged with coccidiosis and Gumboro disease. The results suggest that an inclusion of poor quality of oil in diet, associated with challenge with coccidiosis at first day and Gumboro virus vaccine at 16 day is the best protocol to promote enteritis in broilers at experimental conditions, and that use of standard lesion score was useful to evaluate enteritis.

In broiler production, the litter is reused for consecutives flocks, and it is treated during down time between flocks to reduce its microbial load. Although covering the litter with a plastic canvas is a common litter treatment in the field, there is little scientific information available on its efficacy. The aim of this study was to evaluate the effects of covering broiler litter with a plastic canvas for eight days on litter microbiological, physical, and chemical parameters, and on the intestinal microbiota and immunity of broilers. In the first trial, reused litter from a previous flock was distributed into three treatments, with six replicates each: L1 (negative control, litter free from Salmonella Enteritidis (SE) and Eimeria maxima (EM) and not covered), L2 (positive control, litter with SE and EM, and not covered), and L3 (litter with SE and EM, and covered with plastic canvas for eight days). Litter total bacteria, Enterobacteria, Lactobacillus, SE, and EM counts, and litter pH, temperature, moisture, and ammonia emission were determined on days 1 and 8. In the second trial, broilers were housed on those litters according to the treatments described above, and their intestinal microbiota, gut CD4+ and CD8+ lymphocytes and macrophages, and liver and intestinal pro-inflammatory interleukin (IFN-γ, IL-1β e IL-18) levels were evaluated on days 14 and 28. A significant reduction of litter bacterial populations was observed in the litter covered with plastic canvas. A significantly higher mRNA IFN-γ gene expression (12.5-fold) was observed in the jejunum and liver of broilers reared on the litter with Enterobacteria counts. No EM reduction was observed in the covered litter. Covering reused broiler litter with plastic canvas reduces initial litter bacterial load as a result of the interaction between physical and chemical parameters.

SUMMARY The role of the gastrointestinal tract in the recognition and elimination of pathogenic microorganisms through inflammation is critical for the establishment of health. Sanguinarine is a quaternary ammonium salt that belongs to a group of benzophenanthridine and protopin alkaloids. The present study was conducted to evaluate the effects of using sanguinarine in the drinking water of broilers on reducing the Salmonella Enteritidis count and to assess changes in intestinal morphology and the expression of immune cells in the peripheral blood and intestinal mucosa of broilers challenged with Salmonella Enteritidis. The treatment of Salmonella Enteritidis-challenged broilers with sanguinarine via drinking water reduced Salmonella Enteritidis isolation in the cecum and in the crop at 7 d postinoculation when compared with the control group. Broilers treated with sanguinarine via drinking water presented a significantly lower expression of goblet and CD3 + cells in the duodenum and jejunum and higher expression of cells positive for the markers cD4, cD8α, cD8α bright , cD8α dim , cD8β, tcr Vβ1, and cD28 in the blood compared with the nontreated birds. We also evaluated MHc i, MHc ii and tcr αβ Vβ2, but no differences were observed between treatments.

SUMMARY Different periods of hatching, called hatch windows, occur inside the same hatchery and birds’ development could be affected by this. This study evaluated morphology of the intestinal mucosa and gizzard, and the presence of CD3+ cells in thymus, spleen, and intestinal mucosa in broiler chicks hatched from different egg weights and in different hatch windows. Eggs from breeders at 38 wk of age were evaluated in a factorial 3 × 2 experimental design, with 3 hatch windows (hatching before 472 h of incubation, between 472 and 488 h of incubation, and between 488 and 504 h of incubation) and 2 egg weights (lightweight and heavyweight). Prematurely hatched chicks remaining inside the hatchery for longer periods presented improved koilin membrane development in the gizzard, and smaller presence of CD3+ cells in thymus, spleen, and ileum compared with those birds that hatched close to the standardized time for hatchery opening.

Para avaliar o efeito do probiótico sobre a resposta imunológica de frangos de corte desafiados com Salmonella Minnesota (SM), 60 frangos foram divididos em três grupos: CN- (controle negativo) aves que não foram inoculadas com SM, CP- (controle positivo) aves inoculadas com SM e Probiótico- aves suplementadas na ração com probiótico composto de Lactobacillus acidophilus, L. plantarium, L. rhamnosus, L. bulgaricus, Enterococcus faecium, Streptococcus thermophilus e Bifidobacterium bifidum e desafiadas com SM. Aos 14 dias foi realizada a inoculação com SM e aos 7 e 35 dias foram quantificadas células caliciformes, CD4+ e CD8+ na mucosa intestinal do íleo e ceco. Aves suplementadas com probióticos aos 7 dias de idade apresentaram aumento significativo (P≤0,05) de células caliciformes e CD4+ no íleo e de células CD8+ no ceco. Aos 35 dias houve aumento significativo (P≤0,05) das células CD8+ nas aves inoculadas do CN e Probiótico. A utilização de probióticos proporcionou redução significativa (P≤0,05) da contagem de Salmonella sp.

The use of Bacillus subtilis (BS) as a probiotic in bird feed was studied through the evaluation of its effect on th e infiltration of immune cells in the ileum and cecum mucosa of chickens challenged with Salmonella Minnesota (SM). The birds were divided into three treatment groups; Negative control, containing unchallenged birds; Positive control, with SM challenged birds; and Probiotic, with SM challenged birds fed with a diet containing BS (DSM 17299 2.13 x 10 cfu/g). The birds fed BS showed increased goblet and CD4+ 6 cell counts in the ileum and cecum before being challenged with SM in comparison to the birds not fed BS. After the SM challenge, the birds fed BS showed a reduction in the Salmonella counts at 48 Post Inoculation (PI) in the cloaca and cecum swabs and in litter samples and furthermore a reduction in CD8+ cells in the cecum compared to the challenged birds. Based on the results, it is concluded that feeding BS as a probiotic to broilers reduced the Salmonella spp. counts and thus, affected the mobilization of CD4+ and CD8+ cells in the ileum and cecum mucosa.

The Nisa uranium deposit, located in Central Portugal, has been known since the late 1960s. Some areas were explored at that time. Today, a few open pits and dumps remain in place and are a concern to local authorities. To assess the geoenvironmental problems caused by the main mining exploration composed of an experimental rock blasting, 3D electrical conductivity and resistivity models were made to develop a hydrogeological model to understand the possibility of contaminants transportation, such as uranium, from the dumps towards a dam located nearby. These 3D models were the support to show alteration layer thickness variations and fault zones at depths controlling groundwater circulation. Spectrometric surveys were also carried out and correlated with geology and geoelectrical structure. All this information was used in the construction of the 3D steady state hydrogeological model of the experimental rock blasting of Nisa. In this model, groundwater flow and the contaminant pathways were simulated. Some areas have very high radioactive values resulting from the geological formation characteristics and old dumps. However, results of the environmental assessment using geophysical and hydrogeological methods point to a critical situation restricted only to the area of the experimental rock blasting of the Nisa uranium deposit and its dumps.

Os psitacídeos estão cada vez mais próximos do ser humano devido à facilidade de manutenção que a espécie demanda. Portanto, a preocupação sanitária deve ser crescente, uma vez que as aves são reservatórios naturais de bactérias Gram negativas, como salmonelas, por exemplo. Sob condições de estresse, aves portadoras destas bactérias podem eliminar estes agentes nas fezes e dessa forma transmitir doenças, muitas delas zoonóticas como as salmoneloses para outros animais e seres humanos. O objetivo deste trabalho foi avaliar a presença de Salmonella sp. nas fezes de calopsitas (Nymphicus hollandicus) mantidas em cativeiro. Analisou-se através de cultura bacteriana um total de 129 amostras, sendo 86 suabes cloacais e 43 fezes presentes no fundo das gaiolas. Nenhuma amostra foi positiva para o agente.

Objetivou-se com o presente estudo comparar o efeito de diferentes sorovares de Salmonella na resposta imune local da mucosa do intestino de frangos de corte. Aos sete dias de idade, as aves foram desafiadas com os sorovares S. Enteritidis, S. Typhimurium, S. Senftenberg, S. Mbandaka e S. Minnesota. Foi observado que todos os sorovares testados foram capazes de colonizar o intestino das aves sendo possível o isolamento de Salmonella em suabes de cloaca, 48 h após inoculação. De maneira geral, as aves do grupo controle negativo, que não foram desafiados apresentaram quantidade significativamente menor de células imunológicas na mucosa intestinal do que as aves desafiadas. Porém, verificou-se que os sorovares de Salmonella, utilizados neste estudo, apresentaram diferentes efeitos sobre a dinâmica celular da mucosa do íleo e ceco e afetaram de modo diferente o ganho de peso e ganho médio diário das aves demonstrando distintos graus de patogenicidade. Os sorovares Enteritidis e Typhimurium apresentaram um efeito mais intenso tanto no desempenho quanto na mobilização de células imunológicas na mucosa intestinal de frangos de corte The study was designed to compare the effect of different Salmonella serovars in immune response across the count of CD8+ cells, CD4+ cells, goblet cells and macrophages in the gut mucosa of broilers. During the experimental inoculation at 7 day-old were used Salmonella enterica subspecies enterica sorovars Enteritidis, Typhimurium, Senftenberg, Mbandaka and Minnesota. It was observed that all serovars tested were capable of contaminating the poultry being possible counts of Salmonella in cloacal swabs, 48 h after inoculation and into the crop and cecum, at 14 and 20 day-old. Serovars tested had different effects on broiler performance assessed at 20 days. In the mucosa of the ileum and cecum of broilers, it was observed that some of the serotypes increased CD8 + cells, CD4 + cells, goblet cells and macrophages compared to the negative control group both at 14 and at 20 day-old. S. Enteritidis and S. Typhimurium are the serovars that showed the more intense effect in live performance and in the immune system of birds showing pathogenic characteristic; generally the broilers of the negative control showed significantly less immune cells on the intestinal mucosa than broilers inoculated experimentally. However, it was found that the Salmonella serovars used in this study had different effects on the cellular dynamics of the mucosa of the ileum and cecum and differently affect weight gain and average daily gain of poultry showing different levels of pathogenicity.

Positive and negative ion ejection in the mass range below 200 Dalton is observed for perfluorinated poly-ether surfaces subjected to electron- and ion-beam irradiation. The exciting projectiles are Ar+ ions of 300 and 4000 eV and electrons of 3000 eV. The main positive ions found are fragments of CF3+ ions. Larger ions are found with lower probability. The main negative ion observed is F. The results show that the liquid–vacuum interface is formed by CF3 groups from the polymer.

The present study was designed to compare the ability of different probiotics, applied in feed, to reduce Salmonella colonization and interfere with the cellular dynamics in the intestinal mucosa of broilers challenged with Salmonella enterica enterica sorovar Minnesota (SM). The following probiotics were used: A composed of Bacillus subtillis CCT 7711; B containing Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Enterococcus faecium, Streptococcus thermophilus, and Bifidobacterium bifidum; C consisting of Bacillus subtilis DSM 5750; and D with Enterococcus faecium. All tested probiotics were able to significantly reduce the Salmonella counts in cloacal swabs assessed at 48 h after inoculation when compared with the positive control. All probiotics were able to reduce the Salmonella counts in the cecum when compared to the positive control at 35 days. None of the tested probiotics reduced the Salmonella counts in the crop of broilers at 35 days of age. All probiotics induced an increase in the CD4 + and CD8+ cell counts in the cecum mucosa relative to the negative control group at 7 days of age; only probiotics C and D, reduced significantly the CD8 + cell counts in this same tissue of broilers at 35 days compared to positive control group. The results from this study indicated that the tested probiotics presented different effects on the reduction of SM counts and affected the cell dynamics in the cecum mucosa of broilers differently.

Dois experimentos foram desenvolvidos para avaliar a eficiência de ácidos orgânicos frente a Salmonella enterica enterica sorovar Enteritidis (SE) e Minnesota (SM) em frangos. No primeiro experimento foram avaliados 3 tratamentos: T1 - ração adicionada de ácido orgânico, T2 - ração adicionada de ácido orgânico e ácido orgânico na água de bebida, T3 - grupo controle. Todos os animais foram inoculados com SE, via oral. A utilização de ácidos orgânicos na ração (T1) e na ração e na água (T2) diminuíram a excreção de Salmonella no papo e no ceco 7 dias pós inoculação com SE e houve redução de células CD3+ no jejuno dos frangos. No segundo experimento foram avaliados 4 tratamentos sendo T1 - controle, T2 - controle inoculado via oral com Salmonella Minnesota (SM), T3 - animais inoculados via oral com SM e ácidos orgânicos na ração e T4 - animais inoculados via oral com SM e ácidos orgânicos na ração e na água de bebida. Ácidos orgânicos a ração (T3) e na ração e na água (T4) reduziram a excreção de SM em papo de frangos de corte desafiados, 7 dias após inoculação. O uso de ácidos orgânicos na ração e na ração e na água foram mais eficientes em reduzir SE do que SM.

Tuberculosis (TB) drug resistance survey in six hospitals in Rio de Janeiro, Brazil.To estimate resistance to at least one drug (DR) and multidrug resistance (MDR) and identify associated factors.One-year cross-sectional survey. Hospitals were included as a convenience sample.Of 595 patients investigated, 156 (26.2%) had previously undergone anti-tuberculosis treatment, 433 (72.8%) were not previously treated and information on the remaining 6 was not available. Overall, DR and MDR rates were high, at respectively 102 (17.1%, 95%CI 14.3-20.5) and 44 (7.4%, 95%CI 5.5-9.9) cases. Among individuals not previously treated, 17 had MDR (3.9%, 95%CI 2.4-6.3) and diagnosis in a TB reference hospital was independently associated with MDR (prevalence ratio [PR] 3.3, 95%CI 1.2-8.7) after multivariate analysis. Among previously treated individuals, 27 had MDR (17.3%, 95%CI 11.7-24.2). MDR-TB was independently associated with diagnosis in a TB reference hospital (PR 3.6, 95%CI 1.5-8.7), male sex (PR 2.3, 95%CI 1.2-4.4) and dyspnoea (PR 0.3, 95%CI 0.1-0.7).We found high levels of DR- and MDR-TB. Our study design did not permit us to determine the contribution of community versus nosocomial transmission. Further studies are needed to establish this. Nevertheless, hospitals should be recognised as a potential source of transmission of resistant TB strains and urgent measures to avoid nosocomial TB transmission should be taken.

The human respiratory tract model (HRTM) adopted by ICRP in its Publication 66 accounts for the morphology and physiology of the respiratory tract. The characteristics of air drawn into the lungs and exhaled are greatly influenced by the morphology of the respiratory tract, which causes numerous changes in pressure, flow rate, direction and humidity as air moves into and out of the lungs. These characteristics are important to determine the fractional deposition. It is known that the morphology and physiology are influenced by environmental, occupational and economic conditions. The ICRP recommends, for a reliable evaluation of the regional deposition, the use of parameters from a local population wherever such information is available. The main purpose of this study is to verify the influence of using the morphology and physiology parameters representative of a sample of the Brazilian population on the deposition model of the ICRP Publication 66 model.

In order to ensure that a facility is in compliance with the occupational exposure requirements established by regulatory authorities, the measurements and dose assessments specified in the individual monitoring programme need to be reliable. There are two important questions that shall be addressed here: one is how the licensed facilities can demonstrate to their workers and regulatory bodies compliance with the regulatory limits and the reliability of the results of the individual monitoring programmes; the other concerns the mechanisms used to demonstrate to a facility in another country the reliability of the measurement results of an individual monitoring bioassay programme. The accreditation of the bioassay laboratory, according to ISO/IEC 17025, shall be the basic requirement for obtaining the authorisation granted by the national regulatory authority. For the second question, such confidence can be achieved through International Laboratory Accreditation Cooperation (ILAC).

Bacillemia is a key event in the pathogenesis of tuberculosis. Although current evidence indicates that Mycobacterium tuberculosis bacteremia is rare in patients seronegative for the human immunodeficiency virus, it has been increasingly reported in patients with the acquired immunodeficiency syndrome (AIDS).To determine clinical and laboratory characteristics of patients with AIDS and tuberculosis with and without bacillemia.Fifty patients with AIDS with clinical suspicion of disseminated mycobacterial disease were prospectively selected. Three consecutive blood samples were collected for culture using a standardized protocol.Mycobacterium was isolated from any body site in 42 patients (84%). Bacillemia was detected in 30 (71.4%) of these 42 patients: 11 (28.2%) caused by Mycobacterium avium-intracellulare complex and 19 (71.8%) caused by M tuberculosis. Blood culture was the only method used to confirm the diagnosis in 5 (15%) of the 33 tuberculosis cases. Tuberculosis in patients with AIDS developed with nonspecific insidious symptoms, a remarkable elevated alkaline phosphatase level, and without the classic miliary radiological pattern. We could demonstrate 2 previously unrevealed clinical characteristics of bacteremic tuberculosis in patients with AIDS: a shift to the left in the white blood cell count and abdominal lymph node enlargement. In patients with tuberculosis, the in-hospital mortality rate was higher among patients with bacillemia, although the posttreatment survival rate was comparable.Blood culture is a valuable tool to confirm the clinical diagnosis of disseminated tuberculosis in patients with AIDS and can distinguish patients with characteristic clinical findings and outcome. Abdominal ultrasonography may be an additional helpful tool to identify these patients.

We studied 46 Staphylococcus aureus strains with three patterns of antimicrobial resistance (MARSA, MRSA and MSSA) obtained from inpatients of a large community hospital in Rio de Janeiro, Brazil. The strains showed a single biochemical pattern. On the contrary, remarkable phage-typing differences could be observed. Thirteen strains were associated to phagic group III and the remainder could not be typed even though most of them had shown a weak sensitivity to phage 54. Fourteen strains synthesized one or more enterotoxins. Enterotoxin D was synthesized more often. Neither was EEB produced nor TSSF-1. The results suggested the widespreading of different staphylococci strains in that hospital. There was strong evidence that some cases of nosocomial infections leading to death have been caused by the same S. aureus strain recovered from some inpatients in the intensive care unit.

A prospective study was conducted on 79 advanced immunosuppressed AIDS patients from 1997 to 1999, during which nine cases of tuberculosis (TB) were diagnosed. The main clinical and laboratory characteristics and the response to TB treatment were reviewed. The clinical manifestations of TB were: pulmonary (six cases), extrapulmonary (two cases) and disseminated (one case). These patients were being treated with highly active antiretroviral treatment (HAART) and were not responding. In three cases an optional regimen without rifampicin (RMP) was indicated to maintain HAART during TB treatment. A clinical response to TB treatment (disappearance of fever) was observed in 6/9 patients during a mean of 73 days (SD = 96). The three unresponsive patients were those treated without RMP. A switch to TB regimens containing RMP was proposed and successful. In our study, though it was limited by a small sample size, the response to TB regimens without rifampin was poor in immunossupressed patients failing HAART.

We have measured the energy and angular distribution of the ions emitted from a perfluoropolyether liquid polymer surface due to an incident 320 eV Ar+ beam. The anion distributions are comprised almost exclusively of F?. Substantial amounts of high-energy F? recoils are produced, which can be attributed to multiple-collision processes. The production of these high-energy recoils indicates a very open surface structure, which allows hard (small impact parameter) collisions between Ar+ and individual functional groups of the polymer. Scattered Ar+ is only observed for small total scattering angles.

The present work describes a methodology that can be used for the creation of biomimetic membranes based in sequential assembling of biological molecules, to be used for radiation damage studies in an environment mimicking that of bio‐systems. The major features of the method, the so called layer‐by‐layer technique, as well as the experimental parameters to take into account for heterostructures production are summarized here. Results for radiation damage in DNA containing biomimetic membranes prepared from different conditions methods revealed that the radiation induced damage is dependent on the heterostructure molecular composition, proving that the environment is of extreme importance for the extent of radiation induced damage in biological molecules.