5,321 research outputs found
Preventive and Protective Properties of Pertussis Vaccines: Current Situation and Future Challenges
Pertussis, more commonly known as whooping cough, is a potentially fatal respiratory disease caused by Bordetella pertussis. Two different types of vaccines provide effective protection: killed whole-cell vaccines (wPV) and more recently available acellular vaccines (aPVs) formulated with specific components. Disturbingly, while the vaccines are widely used, the incidence of disease is increasing in several developed countries that have switched from wPV to an aPV. It is suggested that the single most important underlying cause suggested for the resurgence is transmission through asymptomatic infections. While both vaccines protect against disease, a newly developed baboon model has shown that they do not prevent infection. Importantly, wPV-vaccinated animals appeared to clear an infection more rapidly than those vaccinated with aPV, which can relate to the period of possible disease transmission. To ultimately control whooping cough, it is clear that a more effective vaccine is needed that can prevent both disease and transmission. Modifications underway include the elimination of LPS from wPVs to improve their safety profiles and augmentation of aPVs with other bacterium proteins to increase immunogenicity and the longevity of protection. In the interim, vaccinations with aPV during pregnancy appear to protect newborns, the most susceptible to deadly pertussis
Effect of voriconazole on Candida tropicalis biofilms: Relation with ERG genes expression
Candida tropicalis has emerged as the third most prevalent fungal pathogens and its ability to form biofilms has been considered one of the most important virulence factors, since biofilms represent high tolerance to antifungal agents. However, the mechanisms of C. tropicalis biofilm resistance to antifungals remain poorly understood. Thus, the main aim of this work was to infer about the effect of voriconazole on the formation and control of C. tropicalis biofilms and disclose its relationship with ERG genes' expression. Planktonic cells tolerance of several C. tropicalis clinical isolates to voriconazole was determined through of antifungal susceptibility test, and the effect of this azole against C. tropicalis biofilm formation and pre-formed biofilms was evaluated by cultivable cells determination and total biomass quantification. ERG genes expression was analyzed by quantitative real-time polymerase chain reaction. This work showed that C. tropicalis resistance to voriconazole is strain dependent and that voriconazole was able to partially control biofilm formation, but was unable to eradicate C. tropicalis pre-formed biofilms. Moreover, C. tropicalis biofilms resistance to voriconazole seems to be associated with alterations of sterol content in the cell membrane, resulting in ERG genes overexpression. Voriconazole is unable to control C. tropicalis biofilms, and the overexpression of ERG genes is a possible mechanism of biofilm resistance.TheauthorsthanktheFCTfortheStrategic Project of the UID/BIO/04469/2013 unit, FCT and European Union funds (FEDER/COMPETE) for the project RECI/BBBEBI/0179/2012 (FCOMP-01-0124-FEDER-027462). We also would like to acknowledge Pfizer , S.A. for the kindly donation of voriconazole
Confirmation of low genetic diversity and multiple breeding females in a social group of Eurasian badgers from microsatellite and field data
The Eurasian badger (
Meles meles
) is a facultatively social carnivore that shows only rudimentary
co-operative behaviour and a poorly defined social hierarchy. Behavioural evidence
and limited genetic data have suggested that more than one female may breed in a
social group. We combine pregnancy detection by ultrasound and microsatellite locus
scores from a well-studied badger population from Wytham Woods, Oxfordshire, UK, to
demonstrate that multiple females reproduce within a social group. We found that at least
three of seven potential mothers reproduced in a group that contained 11 reproductive age
females and nine offspring. Twelve primers showed variability across the species range and only five of these were variable in Wytham. The microsatellites showed a reduced repeat number, a significantly higher number of nonperfect repeats, and moderate heterozygosity
levels in Wytham. The high frequency of imperfect repeats and demographic phenomena might be responsible for the reduced levels of variability observed in the badger
Detection and quantification of fluconazole within Candida glabrata biofilms
Candida infections are often associated with biofilms and consequent high resistance to most common drugs (e.g. azoles). These resistance mechanisms are not only associated with the biofilm yeast physiology, but also with the presence of a diffusional barrier imposed by the biofilm matrix; however, the real biochemical role of the biofilm components remains very unclear. So, in order to further clarify this issue, we intend to determine, for the first time, fluconazole in biofilms within both supernatants and matrices. Candida biofilms were formed in the presence of fluconazole, and it was recovered from both supernatant and matrix cell-free fractions. Then, high-pressure liquid chromatography was used to identify and quantify the amount of drug that was present in the two fractions. Moreover, this study also showed that the presence of fluconazole in both fractions indicated that the drug administrated did not completely reach the cells, so this phenomena can easily be associated with lower biofilm susceptibility, since the drug administered did not completely reach the cells.This work was supported by the Programa Operacional, Fatores de competitividade-COMPETE and by national funds through FCT-Fundacao para a Ciencia e a Tecnologia on the scope of the projects FCT PTDC/SAU-MIC/119069/2010, RECI/EBB-EBI/0179/2012, PEst-OE/EQB/LA0023/2013 and Celia F. Rodrigue's SFRH/BD/93078/2013 PhD grant. The authors thank the Project "BioHealth-Biotechnology and Bioengineering approaches to improve health quality,'' Ref. NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON. 2-O Novo Norte), QREN, FEDER. We also would like to acknowledge Pfizer (R), S.A., for the kindly donation of fluconazole
Poly-glutamic dendrimer-based conjugates for cancer vaccination - a computational design for targeted delivery of antigens
© 2017 Taylor & Francis. This is an accepted manuscript of an article published by Taylor & Francis in Journal of Drug Targeting on 10 Aug 2017, available online: https://doi.org/10.1080/1061186X.2017.1363213.Computational techniques are useful to predict interaction models and molecular properties for the design of drug delivery systems, such as dendrimers. Dendrimers are hyperbranched macromolecules with repetitive building blocks, defined architecture and functionality. This work evaluated the impact of surface modifications of mannosamine-conjugated multifunctional poly (glutamic acid) (PG)-dendrimers as nanocarriers of the tumor associated antigens (TAA) MART-1, gp100:44 and gp100:209. Their potential to target antigen presenting cells through molecular interactions with mannose receptor (MR1) to promote an efficient and selective antitumor immunotherapeutic effect was also evaluated. Molecular dynamics (MD) simulations and docking studies were performed. Results showed that nitrobenzoxadiazole (NBD)-PG-G4-dendrimer displayed 64 carboxylic groups, however the frontier molecular orbital theory study has indicated that only 32 of those carboxylic groups present on the backbone were available to form covalent bonds with either mannosamine or TAA. No differences in the gap energy of HOMO of conjugated NBD-PG-G4-dendrimer and LUMO of conjugating agents were observed while increasing conjugation loading. When the number of mannosamines conjugated to dendrimer was increased from 16 to 32, the conjugated dendrimer interacted with the receptor with higher affinity. However, due to absence of available carboxylic end groups of backbone chain for further conjugation in a dendrimer with 32 mannosamine, the 16 mannosamines-NBD-PG-G4-dendrimer was chosen to conjugate TAA for added functionality. Docking results showed that the majority of TAA-conjugated NBD-PG-G4-dendrimer demonstrated a favorable interaction with mannosamine binding site on MR1, thus constituting a promising tool for the targeted delivery of TAA. Our in silico approach effectively narrows down the selection of the best candidates for the synthesis of functionalized PG-dendrimers with desired functionalities. The results of this study will significantly reduce the time and efforts required to experimentally obtain modified dendrimers for optimal controlled delivery of antigens to targeted DC.Peer reviewedFinal Accepted Versio
Serious fungal infections in Portugal
There is a lack of knowledge on the epidemiology of fungal infections worldwide because there are no reporting obligations. The aim of this study was to estimate the burden of fungal disease in Portugal as part of a global fungal burden project. Most published epidemiology papers reporting fungal infection rates from Portugal were identified. Where no data existed, specific populations at risk and fungal infection frequencies in those populations were used in order to estimate national incidence or prevalence, depending on the condition. An estimated 1,510,391 persons develop a skin or nail fungal infection each year. The second most common fungal infection in Portugal is recurrent vulvovaginal candidiasis, with an estimated 150,700 women (15-50 years of age) suffering from it every year. In human immunodeficiency virus (HIV)-infected people, oral or oesophageal candidiasis rates were estimated to be 19.5 and 16.8/100,000, respectively. Candidaemia affects 2.19/100,000 patients, in a total of 231 cases nationally. Invasive aspergillosis is less common than in other countries as chronic obstructive pulmonary disease (COPD) is uncommon in Portugal, a total of 240 cases annually. The estimated prevalence of chronic pulmonary aspergillosis after tuberculosis (TB) is 194 cases, whereas its prevalence for all underlying pulmonary conditions was 776 patients. Asthma is common (10% in adults) and we estimate 16,614 and 12,600 people with severe asthma with fungal sensitisation and allergic bronchopulmonary aspergillosis, respectively. Sixty-five patients develop Pneumocystis pneumonia in acquired immune deficiency syndrome (AIDS) and 13 develop cryptococcosis. Overall, we estimate a total number of 1,695,514 fungal infections starting each year in Portugal.info:eu-repo/semantics/publishedVersio
How safe is primary care? A systematic review
Improving patient safety is at the forefront of policy and practice. While considerable progress has been made in understanding the frequency, causes and consequences of error in hospitals, less is known about the safety of primary care.We investigated how often patient safety incidents occur in primary care and how often these were associated with patient harm.We searched 18 databases and contacted international experts to identify published and unpublished studies available between 1 January 1980 and 31 July 2014. Patient safety incidents of any type were eligible. Eligible studies were critically appraised using validated instruments and data were descriptively and narratively synthesised.Nine systematic reviews and 100 primary studies were included. Studies reported between <1 and 24 patient safety incidents per 100 consultations. The median from population-based record review studies was 2-3 incidents for every 100 consultations/records reviewed. It was estimated that around 4% of these incidents may be associated with severe harm, defined as significantly impacting on a patients well-being, including long-term physical or psychological issues or death (range <1% to 44% of incidents). Incidents relating to diagnosis and prescribing were most likely to result in severe harm.Millions of people throughout the world use primary care services on any given day. This review suggests that safety incidents are relatively common, but most do not result in serious harm that reaches the patient. Diagnostic and prescribing incidents are the most likely to result in avoidable harm.This systematic review is registered with the International Prospective Register of Systematic Reviews (PROSPERO CRD42012002304)
Safety of anti-immunoglobulin E therapy with omalizumab in allergic patients at risk of geohelminth infection
BACKGROUND: Although the role of immunoglobulin E (IgE) in immunity against helminth parasites is unclear, there is concern that therapeutic antibodies that neutralize IgE (anti-IgE) may be unsafe in subjects at risk of helminth infection. OBJECTIVE: We conducted an exploratory study to investigate the safety of omalizumab (anti-IgE) in subjects with allergic asthma and/or perennial allergic rhinitis at high risk of intestinal helminth infection. The primary safety outcome was risk of infections with intestinal helminths during anti-IgE therapy. METHODS: A randomized, double-blind, placebo-controlled trial was conducted in 137 subjects (12–30 years) at high risk of geohelminth infection. All subjects received pre-study anthelmintic treatment, followed by 52 weeks' treatment with omalizumab or placebo. RESULTS: Of the omalizumab subjects 50% (34/68) experienced at least one intestinal geohelminth infection compared with 41% (28/69) of placebo subjects [odds ratio (OR) 1.47, 95% confidence interval (CI) 0.74–2.95, one-sided P = 0.14; OR (adjusted for study visit, baseline infection status, gender and age) 2.2 (0.94–5.15); one-sided P = 0.035], providing some evidence for a potential increased incidence of geohelminth infection in subjects receiving omalizumab. Omalizumab therapy was well tolerated, and did not appear to be associated with increased morbidity attributable to intestinal helminths as assessed by clinical and laboratory adverse events, maximal helminth infection intensities and additional anthelmintic requirements. Time to first infection (OR 1.30, 95% CI 0.79–2.15, one-sided P = 0.15) was similar between treatment groups. Infection severity and response to anthelmintics appeared to be unaffected by omalizumab therapy. CONCLUSIONS: In this exploratory study of allergic subjects at high risk of helminth infections, omalizumab therapy appeared to be safe and well tolerated, but may be associated with a modest increase in the incidence of geohelminth infection
Extracts of Feijoa Inhibit Toll-Like Receptor 2 Signaling and Activate Autophagy Implicating a Role in Dietary Control of IBD
Inflammatory bowel disease (IBD) is a heterogeneous chronic inflammatory disease affecting the gut with limited treatment success for its sufferers. This suggests the need for better understanding of the different subtypes of the disease as well as nutritional interventions to compliment current treatments. In this study we assess the ability of a hydrophilic feijoa fraction (F3) to modulate autophagy a process known to regulate inflammation, via TLR2 using IBD cell lines
Factors affecting post-fire crown regeneration in cork oak (Quercus suber L.) trees
Cork oak (Quercus suber) forests are acknowledged
for their biodiversity and economic (mainly cork
production) values. WildWres are one of the main threats
contributing to cork oak decline in the Mediterranean
Basin, and one major question that managers face after Wre
in cork oak stands is whether the burned trees should be
coppiced or not. This decision can be based on the degree
of expected crown regeneration assessed immediately after
Wre. In this study we carried out a post-Wre assessment of
the degree of crown recovery in 858 trees being exploited
for cork production in southern Portugal, 1.5 years after a
wildWre. Using logistic regression, we modelled good or
poor crown recovery probability as a function of tree and
stand variables. The main variables inXuencing the likelihood
of good or poor crown regeneration were bark thickness,
charring height, aspect and tree diameter. We also
developed management models, including simpler but easier
to measure variables, which had a lower predictive
power but can be used to help managers to identify, immediately
after Wre, trees that will likely show good crown
regeneration, and trees that will likely die or show poor
regeneration (and thus, potential candidates for trunk
coppicin
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