Biofilms of non-Candida albicans Candida species : quantification, structure and matrix composition

Most cases of candidiasis have been attributed to C. albicans, but recently, non- Candida albicans Candida (NCAC) species have been identified as common pathogens. The ability of Candida species to form biofilms has important clinical repercussions due to their increased resistance to antifungal therapy and the ability of yeast cells within the biofilms to withstand host immune defenses. Given this clinical importance of the biofilm growth form, the aim of this study was to characterize biofilms produced by three NCAC species, namely C. parapsilosis, C. tropicalis and C. glabrata. The biofilm forming ability of clinical isolates of C. parapsilosis, C. tropicalis and C. glabrata recovered from different sources, was evaluated by crystal violet staining. The structure and morphological characteristics of the biofilms were also assessed by scanning electron microscopy and the biofilm matrix composition analyzed for protein and carbohydrate content. All NCAC species were able to form biofilms although these were less extensive for C. glabrata compared with C. parapsilosis and C. tropicalis. It was evident that C. parapsilosis biofilm production was highly strain dependent, a feature not evident with C. glabrata and C. tropicalis. Scanning electron microscopy revealed structural differences for biofilms with respect to cell morphology and spatial arrangement. Candida parapsilosis biofilm matrices had large amounts of carbohydrate with less protein. Conversely, matrices extracted from C. tropicalis biofilms had low amounts of carbohydrate and protein. Interestingly, C. glabrata biofilm matrix was high in both protein and carbohydrate content. The present work demonstrates that biofilm forming ability, structure and matrix composition are highly species dependent with additional strain variability occurring with C. parapsilosis.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/28341/2006, PDTC/BIO/61112/200

Insights into Candida tropicalis nosocomial infections and virulence factors

Candida tropicalis is considered the first or the second non-Candida albicans Candida (NCAC) species most frequently isolated from candidosis, mainly in patients admitted in intensive care units (ICUs), especially with cancer, requiring prolonged catheterization, or receiving broad-spectrum antibiotics. The proportion of candiduria and candidemia caused by C. tropicalis varies widely with geographical area and patient group. Actually, in certain countries, C. tropicalis is more prevalent, even compared with C. albicans or other NCAC species. Although prophylactic treatments with fluconazole cause a decrease in the frequency of candidosis caused by C. tropicalis, it is increasingly showing a moderate level of fluconazole resistance. The propensity of C. tropicalis for dissemination and the high mortality associated with its infections might be strongly related to the potential of virulence factors exhibited by this species, such as adhesion to different host surfaces, biofilm formation, infection and dissemination, and enzymes secretion. Therefore, the aim of this review is to outline the present knowledge on all the above-mentioned C. tropicalis virulence traits.The authors acknowledge Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES), Brazil, for supporting Melyssa Negri (BEX 4642/06-6) and Fundacao para a Ciencia e Tecnologia (FCT), Portugal, for supporting Sonia Silva (SFRH/BPD/71076/2010), and European Community fund FEDER, trough Program COMPETE under the Project FCOMP-01-0124-FEDER-007025 (PTDC/AMB/68393/2006) is gratefully acknowledged

Haptoglobin study in myasthenia gravis

Objective: A cross-sectional study of haptoglobin (Hp) in myasthenia gravis (MG) was designed, with, the objective to identify its values and correlate them with different disease status. Method: 46 patients were enrolled in the study, all having disease severity established according to the quantitative myasthenia gravis strength scores (QMGSS). Based on the functional scale determined by Myasthenia Gravis Foundation of America (MGFA) recommendations, patients were classified as having: complete stable remission (CSR; n=10); minimal manifestations-O (MMO; n=6), minimal manifestations-1 (MM1; n=4); pharmacological remission (PR; n=6). Two other groups participated: thymomatous patients (T; n=10) and patients without imunosuppression or thymectomy, until the assessment for Hp (WIT; n=10). Hp dosage was done by immunonephelometry, blindly to clinical data. Student's t-test, Anova test and linear regression were employed for statistical analyses. Results: Statistically significant differences occurred between CSR+MMOxWIT groups (86.62x157.57, p < 0.001) and PR+MM1xWIT groups (73.93x157.57, p < 0.001). Linear regression showed correlation between Hp levels and QMGSS (r=0.759, p < 0.001). Conclusion: Our results suggest that Hp may be useful in clinical practice as a disease severity marker in MG.662A22923

Factors associated with gestational weight gain in pregnant women in Rio de Janeiro, Brazil, 2008

Inadequate weight gain during pregnancy is an important predictor of complications for the mother and infant. This cross-sectional study assessed factors associated with inadequate weight gain among women in the third trimester of pregnancy who received prenatal care under the Brazilian Unified National Health System (SUS) in the city of Rio de Janeiro, Brazil, from November 2007 to July 2008. A total of 1,079 pregnant women were interviewed, and adequacy of weight gain was obtained by calculating weight gain as recommended by the U.S. Institute of Medicine. Social, demographic, and obstetric factors were analyzed as independent variables. A multinomial logistic regression model was used, and pregnant women with weight gain below or above the recommended levels were compared to those with adequate weight gain. Low schooling was associated with insufficient weight gain, while excessive gain was observed in women with hypertension and pre-gestational underweight, overweight, and obesity. Nutritional assessment during prenatal care is essential, and interventions should target cases of inadequate weight gain in order to prevent complications for the mother and infant

Intestinal strongyloidiasis and hyperinfection syndrome

In spite of recent advances with experiments on animal models, strongyloidiasis, an infection caused by the nematode parasite Strongyloides stercoralis, has still been an elusive disease. Though endemic in some developing countries, strongyloidiasis still poses a threat to the developed world. Due to the peculiar but characteristic features of autoinfection, hyperinfection syndrome involving only pulmonary and gastrointestinal systems, and disseminated infection with involvement of other organs, strongyloidiasis needs special attention by the physician, especially one serving patients in areas endemic for strongyloidiasis. Strongyloidiasis can occur without any symptoms, or as a potentially fatal hyperinfection or disseminated infection. Th(2 )cell-mediated immunity, humoral immunity and mucosal immunity have been shown to have protective effects against this parasitic infection especially in animal models. Any factors that suppress these mechanisms (such as intercurrent immune suppression or glucocorticoid therapy) could potentially trigger hyperinfection or disseminated infection which could be fatal. Even with the recent advances in laboratory tests, strongyloidiasis is still difficult to diagnose. But once diagnosed, the disease can be treated effectively with antihelminthic drugs like Ivermectin. This review article summarizes a case of strongyloidiasis and various aspects of strongyloidiasis, with emphasis on epidemiology, life cycle of Strongyloides stercoralis, clinical manifestations of the disease, corticosteroids and strongyloidiasis, diagnostic aspects of the disease, various host defense pathways against strongyloidiasis, and available treatment options

Human eosinophil adhesion and degranulation stimulated with eotaxin and RANTES in vitro: Lack of interaction with nitric oxide

<p>Abstract</p> <p>Background</p> <p>Airway eosinophilia is considered a central event in the pathogenesis of asthma. The toxic components of eosinophils are thought to be important in inducing bronchial mucosal injury and dysfunction. Previous studies have suggested an interaction between nitric oxide (NO) and chemokines in modulating eosinophil functions, but this is still conflicting. In the present study, we have carried out functional assays (adhesion and degranulation) and flow cytometry analysis of adhesion molecules (VLA-4 and Mac-1 expression) to evaluate the interactions between NO and CC-chemokines (eotaxin and RANTES) in human eosinophils.</p> <p>Methods</p> <p>Eosinophils were purified using a percoll gradient followed by immunomagnetic cell separator. Cell adhesion and degranulation were evaluated by measuring eosinophil peroxidase (EPO) activity, whereas expression of Mac-1 and VLA-4 was detected using flow cytometry.</p> <p>Results</p> <p>At 4 h incubation, both eotaxin (100 ng/ml) and RANTES (1000 ng/ml) increased by 133% and 131% eosinophil adhesion, respectively. L-NAME alone (but not D-NAME) also increased the eosinophil adhesion, but the co-incubation of L-NAME with eotaxin or RANTES did not further affect the increased adhesion seen with chemokines alone. In addition, L-NAME alone (but not D-NAME) caused a significant cell degranulation, but it did not affect the CC-chemokine-induced cell degranulation. Incubation of eosinophils with eotaxin or RANTES, in absence or presence of L-NAME, did not affect the expression of VLA-4 and Mac-1 on eosinophil surface. Eotaxin and RANTES (100 ng/ml each) also failed to elevate the cyclic GMP levels above baseline in human eosinophils.</p> <p>Conclusion</p> <p>Eotaxin and RANTES increase the eosinophil adhesion to fibronectin-coated plates and promote cell degranulation by NO-independent mechanisms. The failure of CC-chemokines to affect VLA-4 and Mac-1 expression suggests that changes in integrin function (avidity or affinity) are rather involved in the enhanced adhesion.</p

Does General Parenting Context Modify Adolescents' Appraisals and Coping with a Situation of Parental Regulation? The Case of Autonomy-Supportive Parenting

Theory and research suggest that adolescents differ in their appraisals and coping reactions in response to parental regulation. Less is known, however, about factors that determine these differences in adolescents’ responses. In this study, we examined whether adolescents' appraisals and coping reactions depend upon parents’ situation-specific autonomy-supportive or controlling communication style (i.e., the situation) in interaction with adolescents’ past experiences with general autonomy-supportive parenting (i.e., the parenting context). Whereas in Study 1 (N = 176) adolescents’ perceived general autonomy-supportive parenting context was assessed at one point in time, in Study 2 (N = 126) it was assessed multiple times across a 6-year period, allowing for an estimation of trajectories of perceived autonomy-supportive parenting context. In each study, adolescents read a vignette-based scenario depicting a situation of maternal regulation (i.e., a request to study more), which was communicated in either an autonomy-supportive or a controlling way. Following this scenario, they reported upon their appraisals and their anticipated coping reactions. Results of each study indicated that both the autonomy-supportive (relative to the controlling) situation and the perceived autonomy-supportive parenting context generally related to more positive appraisals (i.e., more autonomy need satisfaction, less autonomy need frustration), as well as to more constructive coping responses (i.e., less oppositional defiance and submission, more negotiation and accommodation). In addition, situation × context interactions were found, whereby adolescents growing up in a more autonomy-supportive context seemed to derive greater benefits from the exposure to an autonomy-supportive situation and reacted more constructively to a controlling situation

Environmental isolation, biochemical identification, and antifungal drug susceptibility of Cryptococcus species

Introduction The incidence of opportunistic fungal infections has increased in recent years and is considered an important public health problem. Among systemic and opportunistic mycoses, cryptococcosis is distinguished by its clinical importance due to the increased risk of infection in individuals infected by human immunodeficiency virus. Methods To determine the occurrence of pathogenic Cryptococcus in pigeon excrement in the City of Araraquara, samples were collected from nine environments, including state and municipal schools, abandoned buildings, parks, and a hospital. The isolates were identified using classical tests, and susceptibility testing for the antifungal drugs (fluconazole, itraconazole, voriconazole, and amphotericin B) independently was also performed. After collection, the excrement samples were plated on Niger agar and incubated at room temperature. Results A total of 87 bird dropping samples were collected, and 66.6% were positive for the genus Cryptococcus. The following species were identified: Cryptococcus neoformans (17.2%), Cryptococcus gattii (5.2%), Cryptococcus ater (3.5%), Cryptococcus laurentti (1.7%), and Cryptococcus luteolus (1.7%). A total of 70.7% of the isolates were not identified to the species level and are referred to as Cryptococcus spp. throughout the manuscript. Conclusions Although none of the isolates demonstrated resistance to antifungal drugs, the identification of infested areas, the proper control of birds, and the disinfection of these environments are essential for the epidemiological control of cryptococcosis.Universidade Estadual Paulista (UNESP) Faculdade de Ciencias Farmaceuticas Laboratorio de Micologia ClinicaPrefeitura Municipal de Araraquara Departamento do Meio AmbienteUniversidade Estadual Paulista (UNESP) Faculdade de Ciencias Farmaceuticas Laboratorio de Micologia Clinic