904 resultados para upper repiratory tract infections


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There are reports of the effect of endurance exercise on mucosal immune function and of the effect of short duration exercise on humoral immune function. However, little is known of the effect of endurance exercise on humoral immune function and the related risk of infection. This study examined the effects of an ultra-endurance running race on salivary immunoglobulin-A (s-IgA), serum IgA, leukocyte subset concentrations and the incidence of upper respiratory tract infections (URTI). 


Thirteen male and 4 female competitors provided saliva samples and blood before and at several times after the running race. Self-reported symptoms of URTI were also recorded for 2 weeks before and 2 weeks after the race.

Salivary IgA secretion rate (P=0.005) and ratio to osmolality (P=0.006) were lower immediately postrace and decreased further for at least 2 more h. s-IgA secretion rate had not returned to normal the next morning (P=0.009). Serum IgA concentration was lower post- than prerace (P=0.003) and was even lower the next morning (P<0.001). Leukocyte con centration was elevated postrace (P<0.001), mainly because of an increase in neutrophils (P<0.001) and both remained high the morning after the race (P<0.001). Lymphocyte concentration decreased postrace (P<0.001) and was still depressed the next morning (P=0.032). The incidence of symptoms of URTI was the same in the two 2-week periods before and after the race.

These findings support the hypotheses that an ultra-endurance run may adversely affect mucosal immunity and cause significant changes in the concentration of leukocyte subsets.

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Episódios de sibilância secundários a infecções respiratórias virais são comuns nos primeiros anos de vida. Contudo, sua patogênese e relação com o posterior surgimento de asma permanecem ainda pouco esclarecidos. Com o objetivo de analisar a resposta celular e da IL-10 em lactentes com sibilância, foram analisadas amostras de aspirado nasofaríngeo de 71 lactentes. Os pacientes foram classificados em três grupos: primeiro episódio de sibilância (n=36), sibilância recorrente (n=18) e infecção de vias aéreas superiores (n=17). O exame citológico da secreção nasofaríngea demonstrou uma predominância de neutrófilos em todos os grupos. Não foi evidenciada a presença de eosinófilos na secreção nasofaríngea de nenhum paciente, exceto em um caso do grupo de sibilância recorrente, cujo percentual dessas células foi de 1%. Foram encontrados níveis de IL-10 significativamente aumentados no aspirado nasofaríngeo do grupo com primeiro episódio de sibilância, quando comparados ao grupo de infecção de vias aéreas superiores (p=0,017). Não foi encontrada correlação significativa entre os níveis de IL-10 em secreção nasofaríngea e gravidade do episódio de sibilância. Conclui-se que os neutrófilos são as células que predominam na resposta inflamatória em lactentes com sibilância secundária à infecção respiratória viral e que a IL-10 pode ser uma citocina com participação importante na predisposição à doença obstrutiva brônquica do lactente.

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Introduction: The Health Technology Assessment report on effectiveness, cost-effectiveness and appropriateness of homeopathy was compiled on behalf of the Swiss Federal Office for Public Health (BAG) within the framework of the 'Program of Evaluation of Complementary Medicine (PEK)'. Materials and Methods: Databases accessible by Internet were systematically searched, complemented by manual search and contacts with experts, and evaluated according to internal and external validity criteria. Results: Many high-quality investigations of pre-clinical basic research proved homeopathic high-potencies inducing regulative and specific changes in cells or living organisms. 20 of 22 systematic reviews detected at least a trend in favor of homeopathy. In our estimation 5 studies yielded results indicating clear evidence for homeopathic therapy. The evaluation of 29 studies in the domain 'Upper Respiratory Tract Infections/Allergic Reactions' showed a positive overall result in favor of homeopathy. 6 out of 7 controlled studies were at least equivalent to conventional medical interventions. 8 out of 16 placebocontrolled studies were significant in favor of homeopathy. Swiss regulations grant a high degree of safety due to product and training requirements for homeopathic physicians. Applied properly, classical homeopathy has few side-effects and the use of high-potencies is free of toxic effects. A general health-economic statement about homeopathy cannot be made from the available data. Conclusion: Taking internal and external validity criteria into account, effectiveness of homeopathy can be supported by clinical evidence and professional and adequate application be regarded as safe. Reliable statements of cost-effectiveness are not available at the moment. External and model validity will have to be taken more strongly into consideration in future studies.

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Echinacea preparations are one of the best selling herbal medicinal products with a well established therapeutic use in the prophylaxis of upper respiratory tract infections. Their consumption is increasing, but information about their ability to inhibit cytochrome P450 enzymes (CYP) is fragmentary. The picture is further complicated by a lack of phytochemical characterization of previously tested preparations. Due to its well characterized immunomodulatory activity, the standardized Swiss registered Echinacea purpurea (L.) Moench Echinaforce extract was selected for detailed study. With the single baculovirus-expressed CYP isoforms 1A2, 2C19, 2D9 and 3A4, inhibitory actions were measured by monitoring fluorescent metabolites derived from enzyme substrates (supersome assay). The Echinaforce extract induced mild inhibition of all these isoforms, with CYP 3A4 being the most, and CYP 2D6 the least sensitive enzyme. To assess whether CYP inhibition might be a general feature of Echinacea preparations, an additional nine commercially available preparations were screened using CYP 3A4. All tested preparations were able to inhibit CYP 3A4, but inhibitory potencies (expressed as median inhibitory concentration, IC50) varied by a factor of 150. The alkylamides are thought to be responsible for the immunomodulatory activity of Echinacea, and so the concentration of 2E,4E,8Z,10E/Z-tetranoic acid isobutylamide (1) and total alkylamide content were determined in all preparations, and the latter was found to be associated with their CYP 3A4 inhibitory potency. The chemically pure alkylamides dodeca-2E,4E,8Z,10E/Z-tetranoic acid isobutylamide (1) and dodeca-2E,4E-dieonoic acid isobutylamide (2) showed inhibitory activity on CYP 2C19, 2D6 and 3A4. However, unlike the Echinaforce extract, the alkylamides did not induce CYP 1A2 inhibition. Thus, other, as yet unidentified constituents also contribute to the overall weak inhibitory effects seen with Echinacea preparations in-vitro.

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Developing countries suffer from an array of diseases, of which the developed world is unfamiliar. In order to facilitate the development of community interventions and streamline NGO partnership, needs assessments in targeted areas are conducted. The purpose of this assessment was to attain baseline descriptive data to further understand the needs of the village of Robit, Ethiopia. A trained team collected data from Austin based non-profit Water to Thrive (W2T) on June 1st and 2nd, 2011 through focus groups, key informant interviews, and individual surveys. Qualitative and quantitative data were paired to affirm the results of one another through triangulation. The results identified an apparent need for health intervention and education. Malaria, water-borne disease, respiratory issues (asthma, Upper respiratory tract infections), and maternal and child health were among the evident problems in Robit. There was a clear need for midwife training as well as water sanitation, latrine building, and general illness treatment. Poor road conditions and annual flooding of Robit plays an important role in the poor health and lack of food security of the village. While some evidence of social desirability and recall bias was found in the interview and survey data, the triangulation of findings provided important insights and validity to the needs assessment. ^

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Tennis played at an elite level requires intensive training characterized by repeated bouts of brief intermittent high intensity exercise over relatively long periods of time (1 - 3 h or more). Competition can place additional stress on players. The purpose of this study was to investigate the temporal association between specific components of tennis training and competition, the incidence of upper respiratory tract infections (URT1), and salivary IgA, in a cohort of seventeen elite female tennis players. Timed, whole unstimulated saliva samples were collected before and after selected 1-h training sessions at 2 weekly intervals, over 12 weeks. Salivary IgA concentration was measured by ELISA and IgA secretion rate calculated (mug IgA x ml(-1) x ml saliva x min(-1)). Players reported URTI symptoms and recorded training and competition in daily logs. Data analysis showed that higher incidence of URTI was significantly associated with increased training duration and load, and competition level, on a weekly basis. Salivary IgA secretion rate (S-IgA) dropped significantly after 1 hour of tennis play. Over the 12-week period, pre-exercise salivary IgA concentration and secretion rate were directly associated with the amount of training undertaken during the previous day and week (p < 0.05). However, the decline in S-IgA after 1 h of intense tennis play was also positively related to the duration and load of training undertaken during the previous day and week (p < 0.05). Although exercise-induced suppression of salivary IgA may be a risk factor, it could not accurately predict the occurrence of URTI in this cohort of athletes.

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Background: Urinary tract infections (UTI) are a common and important clinical problem in childhood. Upper urinary tract infections (i.e., acute pyelonephritis) may lead to renal scarring, hypertension, and end-stage renal disease. Despite the presence of simple and reliable methods of preliminary screening of children's urine, urinary tract infection continues to be under diagnosed. Objectives: The aim of this study was to establish prevalence rates of significant bacteriuria in asymptomatic school children by simple urine tests in comparison to standard urine culture techniques in Giza, Egypt. Patients and methods: A total of 1000 apparently healthy school going children (6-12) years, 552 boys (55.2%) and 448 girls (44.8%), were enrolled in this cross-sectional prevalence survey. Results: Overall prevalence of significant bacteriuria was 6%. Higher prevalence occurred in girls (11.4%) than boys (1.6%). Escherichia coli was isolated in 35(58%) cases (3 boys and 32 girls), Staph. aureus in 13 (22%) cases (3 boys and 10 girls), Enterobacter in 6 girls (10%), Kelbsiella pneumoniae in 3 boys (5%) and Proteus vulgaris in 3 girls (5%) Conclusion: Asymptomatic bacteriurea could be detected by urine screening program at school age. Overall prevalence of significant bacteriuria was 6%, with predominance in girls than boys.

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Alogliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor that is a class of relatively new oral hypoglycaemic drugs used in patients with type 2 diabetes (T2DM), can be used as monotherapy or in combination with other anti-diabetic agents, including metformin, pioglitazone, sulfonylureas and insulin with a considerable therapeutic effect. Alogliptin exhibits favorable pharmacokinetic and pharmacodynamic profiles in humans. Alogliptin is mainly metabolized by cytochrome P450 (CYP2D6) and CYP3A4. Dose reduction is recommended for patients with moderate or worse renal impairment. Side effects of alogliptin include nasopharyngitis, upper-respiratory tract infections and headache. Hypoglycaemia is seen in about 1.5% of the T2DM patients. Rare but severe adverse reactions such as acute pancreatitis, serious hypersensitivity including anaphylaxis, angioedema and severe cutaneous reactions such as Stevens-Johnson syndrome have been reported from post-marketing monitoring. Pharmacokinetic interactions have not been observed between alogliptin and other drugs including glyburide, metformin, pioglitazone, insulin and warfarin. The present review aimed to update the clinical information on pharmacodynamics, pharmacokinetics, adverse effects and drug interactions, and to discuss the future directions of alogliptin.

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Prolonged high-intensity training seems to result in increased systemic inflammation, which might explain muscle injury, delayed onset muscle soreness, and overtraining syndrome in athletes. Furthermore, an impaired immune function caused by strenuous exercise leads to the development of upper respiratory tract infections in athletes. Nutraceuticals might help counteract these performance-lowering effects. The use of nanotechnology is an interesting alternative to supply athletes with nutraceuticals, as many of these substances are insoluble in water and are poorly absorbed in the digestive tract. The present chapter starts with a brief review of the effects of exercise on immunity, followed by an analysis on how nutraceuticals such as omega-3 fatty acids, glutamine, BCAAs, or phytochemicals can counteract negative effects of strenuous exercise in athletes. Finally, how nanostructured delivery systems can constitute a new trend in enhancing bioavailability and optimizing the action of nutraceuticals will be discussed, using the example of food beverages.

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Chlamydia trachomatis is the most prevalent bacterial sexually transmitted infection in the developed world and the leading cause of preventable blindness worldwide. As reported by the World Health Organization in 2001, there are approximately 92 million new infections detected annually, costing health systems billions of dollars to treat not only the acute infection, but also to treat infection-associated sequelae. The majority of genital infections are asymptomatic, with 50-70% going undetected. Genital tract infections can be easily treated with antibiotics when detected. Lack of treatment can lead to the development of pelvic inflammatory disease, ectopic pregnancies and tubal factor infertility in women and epididymitis and prostatitis in men. With infection rates on the continual rise and the large number of infections going undetected, there is a need to develop an efficacious vaccine which prevents not only infection, but also the development of infection-associated pathology. Before a vaccine can be developed and administered, the pathogenesis of chlamydial infections needs to be fully understood. This includes the kinetics of ascending infection and the effects of inoculating dose on ascension and development of pathology. The first aim in this study was to examine these factors in a murine model. Female BALB/c mice were infected intravaginally with varying doses of C. muridarum, the mouse variant of human C. trachomatis, and the ascension of infection along the reproductive tract and the time-course of infection-associated pathology development, including inflammatory cell infiltration, pyosalpinx and hydrosalpinx, were determined. It was found that while the inoculating dose did affect the rate and degree of infection, it did not affect any of the pathological parameters examined. This highlighted that the sexual transmission dose may have minimal effect on the development of reproductive sequelae. The results of the first section enabled further studies presented here to use an optimal inoculating dose that would ascend the reproductive tract and cause pathology development, so that vaccine efficacy could be determined. There has been a large amount of research into the development of an efficacious vaccine against genital tract chlamydial infections, with little success. However, there have been no studies examining the effects of the timing of vaccination, including the effects of vaccination during an active genital infection, or after clearance of a previous infection. These are important factors that need to be examined, as it is not yet known whether immunization will enhance not only the individual's immune response, but also pathology development. It is also unknown whether any enhancement of the immune responses will cause the Chlamydia to enter a dormant, persistent state, and possibly further enhance any pathology development. The second section of this study aimed to determine if vaccination during an active genital tract infection, or after clearance of a primary infection, enhanced the murine immune responses and whether any enhanced or reduced pathology occurred. Naïve, actively infected, or previously infected animals were immunized intranasally or transcutaneously with the adjuvants cholera toxin and CpG-ODN in combination with either the major outer membrane protein (MOMP) of C. muridarum, or MOMP and ribonucleotide reductase small chain protein (NrdB) of C. muridarum. It was found that the systemic immune responses in actively or previously infected mice were altered in comparison to animals immunized naïve with the same combinations, however mucosal antibodies were not enhanced. It was also found that there was no difference in pathology development between any of the groups. This suggests that immunization of individuals who may have an asymptomatic infection, or may have been previously exposed to a genital infection, may not benefit from vaccination in terms of enhanced immune responses against re-exposure. The final section of this study aimed to determine if the vaccination regimes mentioned above caused in vivo persistence of C. muridarum in the upper reproductive tracts of mice. As there has been no characterization of C. muridarum persistence in vitro, either ultrastructurally or via transcriptome analysis, this was the first aim of this section. Once it had been shown that C. muridarum could be induced into a persistent state, the gene transcriptional profiles of the selected persistent marker genes were used to determine if persistent infections were indeed present in the upper reproductive tracts of the mice. We found that intranasal immunization during an active infection induced persistent infections in the oviducts, but not the uterine horns, and that intranasal immunization after clearance of infection, caused persistent infections in both the uterine horns and the oviducts of the mice. This is a significant finding, not only because it is the first time that C. muridarum persistence has been characterized in vitro, but also due to the fact that there is minimal characterization of in vivo persistence of any chlamydial species. It is possible that the induction of persistent infections in the reproductive tract might enhance the development of pathology and thereby enhance the risk of infertility, factors that need to be prevented by vaccination, not enhanced. Overall, this study has shown that the inoculating dose does not affect pathology development in the female reproductive tract of infected mice, but does alter the degree and rate of ascending infection. It has also been shown that intranasal immunization during an active genital infection, or after clearance of one, induces persistent infections in the uterine horns and oviducts of mice. This suggests that potential vaccine candidates will need to have these factors closely examined before progressing to clinical trials. This is significant, because if the same situation occurs in humans, a vaccine administered to an asymptomatic, or previously exposed individual may not afford any extra protection and may in fact enhance the risk of development of infection-associated sequelae. This suggests that a vaccine may serve the community better if administered before the commencement of sexual activity.

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Female sex hormones are known to regulate the adaptive and innate immune functions of the female reproductive tract. This review aims to update our current knowledge of the effects of the sex hormones estradiol and progesterone in the female reproductive tract on innate immunity, antigen presentation, specific immune responses, antibody secretion, genital tract infections caused by Chlamydia trachomatis, and vaccine-induced immunity.

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Chlamydia trachomatis infections of the male and female reproductive tracts are the world's leading sexually transmitted bacterial disease, and can lead to damaging pathology, scarring and infertility. The resolution of chlamydial infection requires the development of adaptive immune responses to infection, and includes cell-mediated and humoral immunity. Whilst cluster of differentiation (CD)4+ T cells are known to be essential in clearance of infection [1], they are also associated with immune cell infiltration, autoimmunity and infertility in the testes [2-3]. Conversely, antibodies are less associated with inflammation, are readily transported into the reproductive tracts, and can offer lumenal neutralization of chlamydiae prior to infection. Antibodies, or immunoglobulins (Ig), play a supportive role in the resolution of chlamydial infections, and this thesis sought to define the function of IgA and IgG, against a variety of chlamydial antigens expressed during the intracellular and extracellular stages of the chlamydial developmental cycle. Transport of IgA and IgG into the mucosal lumen is facilitated by receptor-mediated transcytosis yet the expression profile (under normal conditions and during urogenital chlamydial infection) of the polymeric immunoglobulin receptor (pIgR) and the neonatal Fc receptor (FcRn) remains unknown. The expression profile of pIgR and FcRn in the murine male reproductive tract was found to be polarized to the lower and upper reproductive tract tissues respectively. This demonstrates that the two receptors have a tissue tropism, which must be considered when targeting pathogens that colonize different sites. In contrast, the expression of pIgR and FcRn in the female mouse was found to be distributed in both the upper and lower reproductive tracts. When urogenitally infected with Chlamydia muridarum, both male and female reproductive tracts up-regulated expression of pIgR and down-regulated expression of FcRn. Unsurprisingly, the up-regulation of pIgR increased the concentration of IgA in the lumen. However, down-regulation of FcRn, prevented IgG uptake and led to an increase or pooling of IgG in lumenal secretions. As previous studies have identified the importance of pIgR-mediated delivery of IgA, as well as the potential of IgA to bind and neutralize intracellular pathogens, IgA against a variety of chlamydial antigens was investigated. The protection afforded by IgA against the extracellular antigen major outer membrane protein (MOMP), was found to be dependent on pIgR expression in vitro and in vivo. It was also found that in the absence of pIgR, no protection was afforded to mice previously immunized with MOMP. The protection afforded from polyclonal IgA against the intracellular chlamydial antigens; inclusion membrane protein A (IncA), inclusion membrane proteins (IncMem) and secreted chlamydial protease-like activity factor (CPAF) were produced and investigated in vitro. Antigen-specific intracellular IgA was found to bind to the respective antigen within the infected cell, but did not significantly reduce inclusion formation (p > 0.05). This suggests that whilst IgA specific for the selected antigens was transported by pIgR to the chlamydial inclusion, it was unable to prevent growth. Similarly, immunization of male mice with intracellular chlamydial antigens (IncA or IncMem), followed by depletion CD4+ T cells, and subsequent urogenital C. muridarum challenge, provided minimal pIgR-mediated protection. Wild type male mice immunized with IncA showed a 57 % reduction (p < 0.05), and mice deficient in pIgR showed a 35 % reduction (p < 0.05) in reproductive tract chlamydial burden compared to control antigen, and in the absence of CD4+ T cells. This suggests that pIgR and secretory IgA (SIgA) were playing a protective role (21 % pIgR-mediated) in unison with another antigen-specific immune mechanism (36 %). Interestingly, IgA generated during a primary respiratory C. muridarum infection did not provide a significant amount of protection to secondary urogenital C. muridarum challenge. Together, these data suggest that IgA specific for an extracellular antigen (MOMP) can play a strong protective role in chlamydial infections, and that IgA targeting intracellular antigens is also effective but dependent on pIgR expression in tissues. However, whilst not investigated here, IgA targeting and blocking other intracellular chlamydial antigens, that are more essential for replication or type III secretion, may be more efficacious in subunit vaccines. Recently, studies have demonstrated that IgG can neutralize influenza virus by trafficking IgG-bound virus to lysosomes [4]. We sought to determine if this process could also traffic chlamydial antigens for degradation by lysosomes, despite Chlamydia spp. actively inhibiting fusion with the host endocytic pathway. As observed in pIgR-mediated delivery of anti-IncA IgA, FcRn similarly transported IgG specific for IncA which bound the inclusion membrane. Interestingly, FcRn-mediated delivery of anti-IncA IgG significantly decreased inclusion formation by 36 % (p < 0.01), and induced aberrant inclusion morphology. This suggests that unlike IgA, IgG can facilitate additional host cellular responses which affect the intracellular niche of chlamydial growth. Fluorescence microscopy revealed that IgG also bound the inclusion, but unlike influenza studies, did not induce the recruitment of lysosomes. Notably, anti-IncA IgG recruited sequestosomes to the inclusion membrane, markers of the ubiquitin/proteasome pathway and major histocompatibility complex (MHC) class I loading. To determine if the protection against C. muridarum infection afforded by IncA IgG in vitro translated in vivo, wild type mice and mice deficient in functional FcRn and MHC-I, were immunized, depleted of CD4+, and urogenitally infected with C. muridarum. Unlike in pIgR-deficient mice, the protection afforded from IncA immunization was completely abrogated in mice lacking functional FcRn and MHC-I/CD8+. Thus, both anti-IncA IgA and IgG can bind the inclusion in a pIgR and FcRn-mediated manner, respectively. However, only IgG mediates a higher reduction in chlamydial infection in vitro and in vivo suggesting more than steric blocking of IncA had occurred. Unlike anti-MOMP IgA, which reduced chlamydial infection of epithelial cells and male mouse tissues, IgG was found to enhance infectivity in vitro, and in vivo. Opsonization of EBs with MOMP-IgG enhanced inclusion formation of epithelial cells in a MOMP-IgG dose-dependent and FcRn-dependent manner. When MOMP-IgG opsonized EBs were inoculated into the vagina of female mice, a small but non-significant (p > 0.05) enhancement of cervicovaginal C. muridarum shedding was observed three days post infection in mice with functional FcRn. Interestingly, infection with opsonized EBs reduced the intensity of the peak of infection (day six) but protracted the duration of infection by 60 % in wild type mice only. Infection with EBs opsonized in IgG also significantly increased (p < 0.05) hydrosalpinx formation in the oviducts and induced lymphocyte infiltration uterine horns. As MOMP is an immunodominant antigen, and is widely used in vaccines, the ability of IgG specific to extracellular chlamydial antigens to enhance infection and induce pathology needs to be considered. Together, these data suggest that immunoglobulins play a dichotomous role in chlamydial infections, and are dependent on antigen specificity, FcRn and pIgR expression. FcRn was found to be highly expressed in upper male reproductive tract, whilst pIgR was dominantly expressed in the lower reproductive tract. Conversely, female mice expressed FcRn and pIgR in both the lower and upper reproductive tracts. In response to a normal chlamydial infection, pIgR is up-regulated increasing secretory IgA release, but FcRn is down-regulated preventing IgG uptake. Similarly to other studies [5-6], we demonstrate that IgA and IgG generated during primary chlamydial infections plays a minor role in recall immunity, and that antigen-specific subunit vaccines can offer more protection. We also show that both IgA and IgG can be used to target intracellular chlamydial antigens, but that IgG is more effective. Finally, IgA against the extracellular antigen MOMP can afford protection, whist IgG plays a deleterious role by increasing infectivity and inducing damaging immunopathology. Further investigations with additional antigens or combination subunit vaccines will enhance our understanding the protection afforded by antibodies against intracellular and extracellular pathogenic antigens, and help improve the development of an efficacious chlamydial vaccine.

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Streptococcus pyogenes (group A streptococcus) is an important human pathogen, causing a wide array of infections ranging in severity. The majority of S. pyogenes infections are mild upper respiratory tract or skin infections. Severe, invasive infections, such as bacteraemia, are relatively rare, but constitute a major global burden with a high mortality. Certain streptococcal types are associated with a more severe disease and higher mortality. Bacterial, non-necrotizing cellulitis and erysipelas are localised infections of the skin, and although they are usually not life-threatening, they have a tendency to recur and therefore cause substantial morbidity. Despite several efforts aimed at developing an effective and safe vaccine against S. pyogenes infections, no vaccine is yet available. In this study, the epidemiology of invasive S. pyogenes infections in Finland was described over a decade of national, population-based surveillance. Recent trends in incidence, outcome and bacterial types were investigated. The beta-haemolytic streptococci causing cellulitis and erysipelas infections in Finland were studied in a case-control study. Bacterial isolates were characterised using both conventional and molecular typing methods, such as the emm typing, which is the most widely used typing method for beta-haemolytic streptococci. The incidence of invasive S. pyogenes disease has had an increasing trend during the past ten years in Finland, especially from 2006 onwards. Age- and sex-specific differences in the incidence rate were identified, with men having a higher incidence than women, especially among persons aged 45-64 years. In contrast, more infections occurred in women aged 25-34 years than men. Seasonal patterns with occasional peaks during the midsummer and midwinter were observed. Differences in the predisposing factors and underlying conditions of patients may contribute to these distinctions. Case fatality associated with invasive S. pyogenes infections peaked in 2005 (12%) but remained at a reasonably low level (8% overall during 2004-2007) compared to that of other developed countries (mostly exceeding 10%). Changes in the prevalent emm types were associated with the observed increases in incidence and case fatality. In the case-control study, acute bacterial non-necrotizing cellulitis was caused predominantly by Streptococcus dysgalactiae subsp. equisimilis, instead of S. pyogenes. The recurrent nature of cellulitis became evident. This study adds to our understanding of S. pyogenes infections in Finland and provides a basis for comparison to other countries and future trends. emm type surveillance and outcome analyses remain important for detecting such changes in type distribution that might lead to increases in incidence and case fatality. Bacterial characterisation serves as a basis for disease pathogenesis studies and vaccine development.

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Respiratory syncytial virus (RSV) is a major pathogen that primarily infects airway epithelium. Most infants suffer mild upper respiratory tract (URT) symptoms, while approximately one third progress to lower respiratory tract (LRT) involvement. Despite the ubiquity of URT infection, little is known about the relative cytopathogenesis of RSV infection in infant URT and LRT.

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Patients submitted to hemodialysis are at a high risk for healthcare-associated infections (HAI). Presently there are scarce data to allow benchmarking of HAI rates in developing countries. Also, most studies focus only on bloodstream infections (BSI) or local access infections (LAI). Our study aimed to provide a wide overview of HAT epidemiology in a hemodialysis unit in southeastern Brazil. We present data from prospective surveillance carried out from March 2010 through May 2012. Rates were compared (mid-p exact test) and temporally analyzed in Shewhart control charts for Poisson distributions. The overall incidence of BSI was 1.12 per 1000 access-days. The rate was higher for patients performing dialysis through central venous catheters (CVC), either temporary (RR = 13.35, 95% CI = 6.68-26.95) or permanent (RR = 2.10,95% CI = 1.09-4.13), as compared to those with arteriovenous fistula. Control charts identified a BSI outbreak caused by Pseudomonas aeruginosa in April 2010. LAI incidence was 3.80 per 1000 access-days. Incidence rates for other HAI (per 1000 patients-day) were as follows: upper respiratory infections, 1.72; pneumonia, 1.35; urinary tract infections, 1.25; skin/soft tissues infections, 0.93. The data point out to the usefulness of applying methods commonly used in hospital-based surveillance for hemodialysis units. (C) 2013 Elsevier Editora Ltda. All rights reserved.