Dual antibiotherapy of tuberculosis mediated by inhalable locust bean gum microparticles

Despite the existence of effective oral therapy, tuberculosis remains a deadly pathology, namely because of bacterial resistance and incompliance with treatments. Establishing alternative therapeutic approaches is urgently needed and inhalable therapy has a great potential in this regard. As pathogenic bacteria are hosted by alveolar macrophages, the co-localisation of antitubercular drugs and pathogens is thus potentiated by this strategy. This work proposes inhalable therapy of pulmonary tuberculosis mediated by a single locust bean gum (LBG) formulation of microparticles associating both isoniazid and rifabutin, complying with requisites of the World Health Organisation of combined therapy. Microparticles were produced by spray-drying, at LBG/INH/RFB mass ratio of 10/1/0.5. The aerodynamic characterisation of microparticles revealed emitted doses of more than 90% and fine particle fraction of 38%, thus indicating the adequacy of the system to reach the respiratory lung area, thus partially the alveolar region. Cytotoxicity results indicate moderate toxicity (cell viability around 60%), with a concentration-dependent effect. Additionally, rat alveolar macrophages evidenced preferential capture of LBG microparticles, possibly due to chemical composition comprising mannose and galactose units that are specifically recognised by macrophage surface receptors. (C) 2017 Elsevier B.V. All rights reserved.National Portuguese funding through FCT - Fundacao para a Ciencia e a Tecnologia [PTDC/DTP-FTO/0094/2012, UID/BIM/04773/2013, UID/Multi/04326/2013, UID/QUI/00100/2013, PEst-OE/QUI/UI4023/2011

Inhalable antitubercular therapy mediated by locust bean gum microparticles

Tuberculosis remains a major global health problem and alternative therapeutic approaches are needed. Considering the high prevalence of lung tuberculosis (80% of cases), the pulmonary delivery of antitubercular drugs in a carrier system capable of reaching the alveoli, being recognised and phagocytosed by alveolar macrophages (mycobacterium hosts), would be a significant improvement to current oral drug regimens. Locust bean gum (LBG) is a polysaccharide composed of galactose and mannose residues, which may favour specific recognition by macrophages and potentiate phagocytosis. LBG microparticles produced by spray-drying are reported herein for the first time, incorporating either isoniazid or rifabutin, first-line antitubercular drugs (association efficiencies >82%). Microparticles have adequate theoretical properties for deep lung delivery (aerodynamic diameters between 1.15 and 1.67 μm). The cytotoxic evaluation in lung epithelial cells (A549 cells) and macrophages (THP-1 cells) revealed a toxic effect from rifabutin-loaded microparticles at the highest concentrations, but we may consider that these were very high comparing with in vivo conditions. LBG microparticles further evidenced strong ability to be captured by macrophages (percentage of phagocytosis >94%). Overall, the obtained data indicated the potential of the proposed system for tuberculosis therapy

Intraventricular hemorrhage in preterm infants: risk factors and neurodevelopmental outcomes

Introduction: Germinal matrix hemorrhage-intraventricular hemorrhage (GMH-IVH) is the most common form of intracranial hemorrhage in preterm infants. We evaluated risk factors for GMH-IVH in preterm infants born before 32 weeks of gestational age. Secondary outcomes included the characterization of neurodevelopmental (ND) prognosis at 24-36 months of corrected age. Methods: We included infants admitted to our Neonatal Intensive Care Unit between May 2011 and January 2017. A total of 161 infants were enrolled, divided into the GMH-IVH group (n = 40) and control group (n = 121). A secondary cohort included the follow-up group (n = 124) at 24-36 months of corrected age. The association of GMH-IVH with risk factors and ND outcomes was investigated. Results: The incidence of GMH-IVH was 24.8%. Significant risk factors for GMH-IVH were exposure to any resuscitation in the Delivery Room (adjusted odds ratio [aOR]: 34.1; 95% confidence interval [CI] 1.8-657.5) and a low Apgar score at 5 minutes of life (aOR: 0.4; 95% CI: 0.2-0.9). The incidence of retinopathy of prematurity was significantly higher in the grade I GMH-IVH (p < 0.001) group. Gross motor and locomotion dysfunction were significantly more frequent in the GMH-IVH group (24.1% vs. 4.4%; p = 0.004) as was auditory and language dysfunction (24.1% vs. 7.8%; p = 0.040). GMH-IVH was independently associated with visual impairment (aOR: 21.6; 95% CI: 3.2-145.0).  Conclusions: Lower Apgar score at 5 minutes of life and any resuscitation were independent risk factors for GMH-IVH. GMH-IVH was associated with higher ND morbidity. ND prognosis of grade II GMH-IVH was comparable to grade III GMH-IVH

Estudo clínico-epidemiológico da infeção por Bordetella pertussis num hospital português nível III

Introdução: A incidência da tosse convulsa tem aumentado nos últimos anos sobretudo nos países desenvolvidos, apesar da elevada cobertura vacinal. Os pequenos lactentes são o grupo mais suscetível de complicações.Objetivos: Caracterizar os casos pediátricos de tosse convulsa confirmada laboratorialmente. Determinar fatores clínicos e analíticos preditivos de complicações.Métodos: Estudo retrospetivo observacional por análise dos processos clínicos dos doentes pediátricos internados num hospital português nívelIII com o diagnóstico de tosse convulsa confirmada laboratorialmente de janeirode 2005 asetembro de 2012.Resultados: Identificaram-se 47 casos de infeção por Bordetella pertussis, com dois picos de incidência: em 2008 (25,5%) e em 2012 (29,8%). A mediana da idade foi dois meses, sendo que 76,6% dos casos apresentava idade inferior a três meses. Oito(17%) doentes tinham recebido previamente três ou mais doses de vacina pertussis acelular. Identificou-se a fonte provável de infeção em 42,6% dos casos (pais em 80%). Verificaram-se complicações em 38,3% dos casos, a maioria associada a patologia respiratória. A leucocitose e a linfocitose revelaram-se preditores de tosse convulsa complicada. A reação leucemóide associou-se a elevada morbilidade e mortalidade (um óbito e um caso com sequelas de encefalopatia).Discussão: Neste estudo verificou-se um aumento da incidência da tosse convulsa nos últimos anos, o que questiona a necessidade de adotar estratégias vacinais com o objetivo de diminuir a transmissão da doença. A leucocitose e a linfocitose revelaram-se fatores preditores de complicações. A reação leucemóide cursou com elevada morbi-mortalidade.Palavras-chave: tosse convulsa, pediatria, complicações, leucocitose,linfocitos

Pontastacus leptodactylus (Eschscholtz, 1823) and Faxonius limosus (Rafinesque, 1817) as new, alternative sources of chitin and chitosan

The growing demand for chitin and chitosan makes it necessary to look for new sources of these polymers and to develop more environmentally friendly methods for their isolation. The subjects of the current study were chitin and chitosan extracted from shells of two crayfish species: P. leptodactylus and F. limosus. The obtained polymers were characterized by physicochemical properties (molecular weight, thermal stability, and structure). The obtained chitosan was evaluated regarding biocompatibility and antimicrobial activity. The yield of chitin obtained from P. leptodactylus and F. limosus with a standard method was 22 ± 2.7% and 20 ± 3.6% (w/w), respectively (a preliminary extraction with a natural deep eutectic solvent was performed successfully only for P. leptodactylus). The yield of chitosan production was 15 ± 0.3% and 14 ± 4.2%, respectively. Both chitosan samples showed antimicrobial activity against E. coli and S. aureus. Cytotoxicity assays revealed a time- and concentration-dependent effect, with a milder impact at concentrations up to 250 µg/mL. A more favourable profile was observed for chitosan from F. limosus shells.info:eu-repo/semantics/publishedVersio

Nanoencapsulation of Gla-Rich Protein (GRP) as a Novel Approach to Target Inflammation

LA/P/0101/2020 LA/P/0140/2020 AAC nº 41/ALG/2020—Project nº 072583—NUTRISAFEChronic inflammation is a major driver of chronic inflammatory diseases (CIDs), with a tremendous impact worldwide. Besides its function as a pathological calcification inhibitor, vitamin K-dependent protein Gla-rich protein (GRP) was shown to act as an anti-inflammatory agent independently of its gamma-carboxylation status. Although GRP’s therapeutic potential has been highlighted, its low solubility at physiological pH still constitutes a major challenge for its biomedical application. In this work, we produced fluorescein-labeled chitosan-tripolyphosphate nanoparticles containing non-carboxylated GRP (ucGRP) (FCNG) via ionotropic gelation, increasing its bioavail-ability, stability, and anti-inflammatory potential. The results indicate the nanosized nature of FCNG with PDI and a zeta potential suitable for biomedical applications. FCNG’s anti-inflammatory activity was studied in macrophage-differentiated THP1 cells, and in primary vascular smooth muscle cells and chondrocytes, inflamed with LPS, TNFα and IL-1β, respectively. In all these in vitro human cell systems, FCNG treatments resulted in increased intra and extracellular GRP levels, and decreased pro-inflammatory responses of target cells, by decreasing pro-inflammatory cytokines and inflammation mediators. These results suggest the retained anti-inflammatory bioactivity of ucGRP in FCNG, strengthening the potential use of ucGRP as an anti-inflammatory agent with a wide spectrum of application, and opening up perspectives for its therapeutic application in CIDs.publishersversionpublishe