Probiotic microcarrier: a continuous folate producer

The recommended daily intake of folate (B-complex vitamin) for an adult varies between 200-400 µg, being the intake of folate inefficient due its extremely unstable chemical forms. The aim of this work is the creation of model to folate in situ production using probiotics. However, three main issues need to be overcome: (a) probiotic bacteria should be protected towards the gastric medium (encapsulation); (b) microcarriers size should be smaller than 100 µm, to avoid modifying food texture; and (c) microcarriers should adhere to gut epithelium in order to increase bacteria residence time. Lactococcus lactis cremoris was grown in milk (30ºC). Alginate-based microcarriers were produced and three layers were built using the layer-by-layer technique in that worder: poly-L-lysine; sodium alginate; chitosan. Confocal microscopy was used to confirm the consequent adhesion of the layers (poly-L-lysine/FITC; chitosan/rhodamine). After production the microcarriers where put into a 10 mL solution of KCl-HCl (pH 2 - 1 hour), at 100 rpm and then into a PBS solution (pH 7.2 - 3 hours) in order to mimic the passage through the gastrointestinal tract. The utilization of free bacteria (LLC) in milk showed an increase of folate content in 4.73 µg/L after 6 h. The average size of the microcarriers from 21.01 ± 0.49 µm to 39.84 ± 0.79 µm when the pH increased from 2 to 7.2. The size averages obtained were smaller than 100 µm and showed a swelling capacity (particles duplicate their size upon passing from pH 2 to pH 7.2), being confirmed by confocal microscopy images the correct adhesion of the different layers after this experiment and the stability of the microcarriers. Microcarriers produced through LbL showed great potential for encapsulation of probiotics, allowing their protection against harsh gastrointestinal conditions, predicting their use as a microcarrier for in situ folate production

Short chain U(600) di-urea cross-linked poly(oxyethylene)/siloxane ormolytes doped with lanthanum triflate salt

Promising La3+-doped electrolytes based on a hybrid poly(oxyethylene)/siliceous host matrix, U(600), have been produced. The organic and inorganic components of the hybrid structure are covalently bonded through urea linkages. The low molecular weight of the polyether segments of U(600) is thought to be responsible for the total amorphous character and high conductivity at room temperature (1.1×10−4 S cm−1) of these ormolytes.Fundação para a Ciência e a Tecnologia (FCT

Morphological and conductivity studies of di-ureasil xerogels containing lithium triflate

Sol–gel derived poly(oxyethylene)/siloxane hybrids doped with lithium triflate, LiCF3SO3, have been investigated. The host hybrid matrix of these materials, named di-ureasil and represented by U(600), is composed by a siliceous framework to which polyether chains containing 8.5 oxyethylene repeat units are covalently bonded through urea linkages. Xerogel samples U(600)nLiCF3SO3 with n (where n is the molar ratio of oxyethylene moieties per Li+ ion) between ∞ and 0.1 have been examined. X-ray diffraction and differential scanning calorimetry have provided conclusive evidence that the xerogels analyzed are entirely amorphous. The salt-rich material with n=1 exhibits the highest conductivity over the whole range of temperature analyzed (e.g. 4.3×10−6 and 2.0×10−4 Ω−1 cm−1, respectively, at 25 and 94 °C).Fundação para a Ciência e a Tecnologia (FCT

Short-chain di-ureasil ormolytes doped with potassium triflate: Phase diagram and conductivity behavior

Di-urea cross-linked poly(oxyethylene)/siloxane hybrids, synthesized by the sol-gel process and containing a wide concentration range of potassium triflate, KCF3SO3, have been analyzed by x-ray diffraction and differential scanning calorimetry. The pseudo-phase diagram proposed has been taken into account in the interpretation of the complex impedance measurements. The xerogels prepared are obtained as transparent, thin monoliths . At room temperature the highest conductivity found was 2 x 10-6Scm-1.Fundação para a Ciência e a Tecnologia (FCT

Layer-by-layer microcarrier production and characterization as a model to probiotics microencapsulation

The recommended daily intake of folate (B-complex vitamin) for an adult varies between 200 and 400 g, being the intake of folate inefficient due its extremely unstable chemical forms. One of the presented solutions is the in situ production using probiotics. However, two concerns exist for this solution: a) probiotic bacteria may need protection towards the gastric medium (encapsulation); and b) microcapsule sizes should be smaller than 100 m, to avoid modifying food texture. Alginate-based microcapsules were produced and three layers were added using the layer-by-layer technique: 1st - poly-L-lysine (0.1%); 2nd - sodium alginate (1%); 3rd - chitosan (0.03%). Confocal microscopy was used to confirm the consequent adhesion of the layers, and if they were in the correct position (the layers labelled were the first (Poly-l-lysine/FITC) and the third layer (Chitosan/Rhodamine). After production the particles where put into a 10 mL solution of KCl-HCl (pH 2) during 1 hour, at 100 rpm and then into a PBS solution (pH 7.2), during 3 hours in order to mimic the gastrointestinal tract during digestion. The average size of the particles was 21.01 ± 0.493 m and 39.84 ± 0.794 m during the process at pH 2 and at pH 7.2, respectively. The sizes were smaller than 100 m and showed a swelling capacity (particles duplicate their size upon passing from pH 2 to pH 7.2). Confocal images showed the adhesion of the different layers, also proving indirectly the existence of the second layer (not labelled). Further, after the contact with the KCl-HCl (pH 2) and PBS (7.2) media, the structure of the capsules with the layers was maintained, thus showing the robustness of this structure at pH values typical of the gastrointestinal system. Alginate microcapsules production through LbL technique showed potential for encapsulation of probiotics, allowing their protection against harsh conditions in gastrointestinal tract.info:eu-repo/semantics/publishedVersio

Comparative Genomics of Vancomycin-Resistant Staphylococcus aureus Strains and Their Positions within the Clade Most Commonly Associated with Methicillin-Resistant S. aureus Hospital-Acquired Infection in the United States

Methicillin-resistant Staphylococcus aureus (MRSA) strains are leading causes of hospital-acquired infections in the United States, and clonal cluster 5 (CC5) is the predominant lineage responsible for these infections. Since 2002, there have been 12 cases of vancomycin-resistant S. aureus (VRSA) infection in the United States—all CC5 strains. To understand this genetic background and what distinguishes it from other lineages, we generated and analyzed high-quality draft genome sequences for all available VRSA strains. Sequence comparisons show unambiguously that each strain independently acquired Tn1546 and that all VRSA strains last shared a common ancestor over 50 years ago, well before the occurrence of vancomycin resistance in this species. In contrast to existing hypotheses on what predisposes this lineage to acquire Tn1546, the barrier posed by restriction systems appears to be intact in most VRSA strains. However, VRSA (and other CC5) strains were found to possess a constellation of traits that appears to be optimized for proliferation in precisely the types of polymicrobic infection where transfer could occur. They lack a bacteriocin operon that would be predicted to limit the occurrence of non-CC5 strains in mixed infection and harbor a cluster of unique superantigens and lipoproteins to confound host immunity. A frameshift in dprA, which in other microbes influences uptake of foreign DNA, may also make this lineage conducive to foreign DNA acquisition

Calibration of myocardial T2 and T1 against iron concentration.

BACKGROUND: The assessment of myocardial iron using T2* cardiovascular magnetic resonance (CMR) has been validated and calibrated, and is in clinical use. However, there is very limited data assessing the relaxation parameters T1 and T2 for measurement of human myocardial iron. METHODS: Twelve hearts were examined from transfusion-dependent patients: 11 with end-stage heart failure, either following death (n=7) or cardiac transplantation (n=4), and 1 heart from a patient who died from a stroke with no cardiac iron loading. Ex-vivo R1 and R2 measurements (R1=1/T1 and R2=1/T2) at 1.5 Tesla were compared with myocardial iron concentration measured using inductively coupled plasma atomic emission spectroscopy. RESULTS: From a single myocardial slice in formalin which was repeatedly examined, a modest decrease in T2 was observed with time, from mean (± SD) 23.7 ± 0.93 ms at baseline (13 days after death and formalin fixation) to 18.5 ± 1.41 ms at day 566 (p<0.001). Raw T2 values were therefore adjusted to correct for this fall over time. Myocardial R2 was correlated with iron concentration [Fe] (R2 0.566, p<0.001), but the correlation was stronger between LnR2 and Ln[Fe] (R2 0.790, p<0.001). The relation was [Fe] = 5081•(T2)-2.22 between T2 (ms) and myocardial iron (mg/g dry weight). Analysis of T1 proved challenging with a dichotomous distribution of T1, with very short T1 (mean 72.3 ± 25.8 ms) that was independent of iron concentration in all hearts stored in formalin for greater than 12 months. In the remaining hearts stored for <10 weeks prior to scanning, LnR1 and iron concentration were correlated but with marked scatter (R2 0.517, p<0.001). A linear relationship was present between T1 and T2 in the hearts stored for a short period (R2 0.657, p<0.001). CONCLUSION: Myocardial T2 correlates well with myocardial iron concentration, which raises the possibility that T2 may provide additive information to T2* for patients with myocardial siderosis. However, ex-vivo T1 measurements are less reliable due to the severe chemical effects of formalin on T1 shortening, and therefore T1 calibration may only be practical from in-vivo human studies

Early Adverse Events, HPA Activity and Rostral Anterior Cingulate Volume in MDD

Prior studies have independently reported associations between major depressive disorder (MDD), elevated cortisol concentrations, early adverse events and region-specific decreases in grey matter volume, but the relationships among these variables are unclear. In the present study, we sought to evaluate the relationships between grey matter volume, early adverse events and cortisol levels in MDD.Grey matter volume was compared between 19 controls and 19 individuals with MDD using voxel-based morphometry. A history of early adverse events was assessed using the Childhood Trauma Questionnaire. Subjects also provided salivary cortisol samples. Depressed patients showed decreased grey matter volume in the rostral ACC as compared to controls. Rostral ACC volume was inversely correlated with both cortisol and early adverse events.These findings suggest a key relationship between ACC morphology, a history of early adverse events and circulating cortisol in the pathophysiology of MDD

The Effectiveness of a Home Care Program for Supporting Caregivers of Persons with Dementia in Developing Countries: A Randomised Controlled Trial from Goa, India

OBJECTIVES: To develop and evaluate the effectiveness of a home based intervention in reducing caregiver burden, promoting caregiver mental health and reducing behavioural problems in elderly persons with dementia. METHODOLOGY AND PRINCIPAL FINDINGS: This was a randomised controlled trial in which the person with dementia-caregiver dyad was randomly allocated either to receive the intervention immediately or to a waiting list group which received the intervention after 6 months. It was carried out in communities based in two talukas (administrative blocks) in Goa, India. Mild to moderate cases with dementia (diagnosed using the DSM IV criteria and graded using the Clinical Dementia Rating scale) and their caregivers were included in the trial. Community based intervention provided by a team consisting of Home Care Advisors who were supervised by a counselor and a psychiatrist, focusing on supporting the caregiver through information on dementia, guidance on behaviour management, a single psychiatric assessment and psychotropic medication if needed. We measured caregiver mental health (General Health Questionnaire), caregiver burden (Zarit Burden Score), distress due to behavioural disturbances (NPI-D), behavioural problems in the subject (NPI-S) and activities of daily living in the elder with dementia (EASI). Outcome evaluations were masked to the allocation status. We analysed each outcome with a mixed effects model. 81 families enrolled in the trial; 41 were randomly allocated to the intervention. 59 completed the trial and 18 died during the trial. The intervention led to a significant reduction of GHQ (-1.12, 95% CI -2.07 to -0.17) and NPI-D scores (-1.96, 95%CI -3.51 to -0.41) and non-significant reductions in the ZBS, EASI and NPI-S scores. We also observed a non-significant reduction in the total number of deaths in people with dementia in the intervention arm (OR 0.34, 95% CI 0.01 to 1.03). CONCLUSION: Home based support for caregivers of persons with dementia, which emphasizes the use of locally available, low-cost human resources, is feasible, acceptable and leads to significant improvements in caregiver mental health and burden of caring. ClinicalTrials.gov NCT00479271