Finite-dimensional representations of twisted hyper loop algebras

We investigate the category of finite-dimensional representations of twisted hyper loop algebras, i.e., the hyperalgebras associated to twisted loop algebras over finite-dimensional simple Lie algebras. The main results are the classification of the irreducible modules, the definition of the universal highest-weight modules, called the Weyl modules, and, under a certain mild restriction on the characteristic of the ground field, a proof that the simple modules and the Weyl modules for the twisted hyper loop algebras are isomorphic to appropriate simple and Weyl modules for the non-twisted hyper loop algebras, respectively, via restriction of the action

Proton momentum distribution in a protein hydration shell

The momentum distribution of protons in the hydration shell of a globular protein has been measured through deep inelastic neutron scattering at 180 and 290 K, below and above the crossover temperature T-c=1.23T(g), where T-g=219 K is the glass transition temperature. It is found that the mean kinetic energy of the water hydrogens shows no temperature dependence, but the measurements are accurate enough to indicate a sensible change of momentum distribution and effective potential felt by protons, compatible with the transition from a single to a double potential well. This could support the presence of tunneling effects even at room temperature, playing an important role in biological function

STRUCTURAL AND STEREOSPECIFIC REQUIREMENTS FOR THE NUCLEOSIDE-TRIGGERED GERMINATION OF BACILLUS-CEREUS SPORES

A selection of adenosine analogues was tested for their ability to trigger germination of Bacillus cereus NCIB 8122 spores. The germination-inducing activity was governed by the structural properties of the sugar rather than the base moieties of the nucleosides. Among the sugar-modified analogues, only those containing a 2'-deoxy-D-ribose moiety promoted spore germination. Requirements for a specific molecular structure of the base were not clearly identified, although the highest activity was observed when substituents were inserted at position 6 of the purine ring. All the base-modified analogues, even those such as coformycin and 2'-deoxycoformycin with an expanded base ring, retained the germination-inducing activity of adenosine. However, of the two 2'-deoxycoformycin diastereoisomers characterized by an asymmetric carbon atom at position 8 of the homopurine ring, only the 8S-isomer induced germination, thus indicating that stereospecific configuration of the inducer, at least in the case of 2'-deoxycoformycin, appears to be essential for the initiation of spore germination. The differences in the germination-inducing activity of the various analogues tested were not affected significantly by spore activation at different temperatures, although the higher the activation temperature, the lower was the concentration of each analogue required for maximum germination

FlhF, a signal recognition particle-like GTPase, is involved in the regulation of flagellar arrangement, motility behaviour and protein secretion in Bacillus cereus

Flagellar arrangement is a highly conserved feature within bacterial species. However, only a few genes regulating cell flagellation have been described in polar flagellate bacteria. This report demonstrates that the arrangement of flagella in the peritrichous flagellate Bacillus cereus is controlled by flhF. Disruption of flhF in B. cereus led to a reduction in the number of flagella from 10-12 to 1-3 filaments per cell in the insertion mutant MP06. Moreover, compared to the parental strain, MP06 exhibited: (i) shorter smooth swimming phases, causing reduced swimming motility but not affecting chemotaxis; (ii) complete inhibition of swarming motility, as differentiated swarm cells were never detected; (iii) an increased amount of extracellular proteins; and (iv) differential export of virulence determinants, such as haemolysin BL (HBL), phosphatidylcholine-preferring phospholipase C (PC-PLC) and non-haemolytic enterotoxin (NHE). Introduction of a plasmid harbouring flhF (pDGflhF) into MP06 completely restored the wild-type phenotype in the trans-complemented strain MP07. B. cereus flhF was found to constitute a monocistronic transcriptional unit and its overexpression did not produce abnormal features in the wild-type background. Characterization of a B. cereus mutant (MP05) carrying a partial flhF deletion indicated that the last C-terminal domain of FlhF is involved in protein export while not required for flagellar arrangement and motility behaviour. Taken together, these data suggest that B. cereus FlhF is a promising candidate for connecting diverse cellular functions, such as flagellar arrangement, motility behaviour, pattern of protein secretion and virulence phenotype

Survival and persistence of Bacillus clausii in the human gastrointestinal tract following oral administration as spore-based probiotic formulation

AIMS: This study aimed to investigate the fate of Bacillus clausii spores orally administered as lyophilized or liquid formulation to healthy volunteers. METHODS AND RESULTS: The study was a randomized, open-label, cross-over trial in which two commercial probiotic formulations containing spores of four antibiotic-resistant B. clausii strains (OC, NR, SIN, T) were given as a single dose administration. Faecal B. clausii units of each strain were counted on selective media and extrapolated for the total weight of evacuated faeces. RAPD-PCR typing was used to confirm B. clausii identification. Bacillus clausii was found alive in faeces for up to 12 days. In some volunteers, the recovered amount of OC, NR or SIN was higher than the number of administered spores. Bioequivalence among the two formulations was demonstrated. CONCLUSIONS: Bacillus clausii spores survive transit through the human gastrointestinal tract. They can undergo germination, outgrowth and multiplication as vegetative forms. Bacillus clausii strains can have different ability to survive in the intestinal environment. Bacillus clausii spores administered as liquid suspension or lyophilized form behave similarly in vivo. SIGNIFICANCE AND IMPACT OF THE STUDY: This work contributes towards a better understanding of the behaviour of B. clausii spores as probiotics

Contribution of Surfactin and SwrA to Flagellin Expression, Swimming, and Surface Motility in Bacillus subtilis.

Multicellular communities produced by Bacillus subtilis can adopt sliding or swarming to translocate over surfaces. While sliding is a flagellum-independent motility produced by the expansive forces in a growing colony, swarming requires flagellar functionality and is characterized by the appearance of hyperflagellated swarm cells that associate in bundles or rafts during movement. Previous work has shown that swarming by undomesticated B. subtilis strains requires swrA, a gene that upregulates the expression of flagellar genes and increases swimming motility, and surfactin, a lipopeptide biosurfactant that also facilitates sliding. Through an analysis of swrA(+) and swrA mutant laboratory strains with or without a mutation in sfp (a gene involved in surfactin production), we show that both swrA and surfactin upregulate the transcription of the flagellin gene and increase bacterial swimming. Surfactin also allows the nonswarming swrA mutant strain to efficiently colonize moist surfaces by sliding. Finally, we reconfirm the essential role of swrA in swarming and show that surfactin, which increases surface wettability, allows swrA(+) strains to produce swarm cells on media at low humidity

Depth profile investigations of surface modifications of limestone artifacts by laser-induced breakdown spectroscopy.

Made available in DSpace on 2017-11-01T23:23:05Z (GMT). No. of bitstreams: 1 PROCI17Depthprofileinvestigations....pdf: 1977315 bytes, checksum: f46ba065d28554ead651738267cea5a4 (MD5) Previous issue date: 2017-10-30bitstream/item/165807/1/PROCI-17-Depth-profile-investigations....pd

Adapting and implementing training, guidelines and treatment cards to improve primary care-based hypertension and diabetes management in a fragile context: results of a feasibility study in Sierra Leone

Background Sierra Leone, a fragile country, is facing an increasingly significant burden of non-communicable diseases (NCDs). Facilitated by an international partnership, a project was developed to adapt and pilot desktop guidelines and other clinical support tools to strengthen primary care-based hypertension and diabetes diagnosis and management in Bombali district, Sierra Leone between 2018 and 2019. This study assesses the feasibility of the project through analysis of the processes of intervention adaptation and development, delivery of training and implementation of a care improvement package and preliminary outcomes of the intervention. Methods A mixed-method approach was used for the assessment, including 51 semi-structured interviews, review of routine treatment cards (retrieved for newly registered hypertensive and diabetic patients from June 2018 to March 2019 followed up for three months) and mentoring data, and observation of training. Thematic analysis was used for qualitative data and descriptive trend analysis and t-test was used for quantitative data, wherever appropriate. Results A Technical Working Group, established at district and national level, helped to adapt and develop the context-specific desktop guidelines for clinical management and lifestyle interventions and associated training curriculum and modules for community health officers (CHOs). Following a four-day training of CHOs, focusing on communication skills, diagnosis and management of hypertension and diabetes, and thanks to a CHO-based mentorship strategy, there was observed improvement of NCD knowledge and care processes regarding diagnosis, treatment, lifestyle education and follow up. The intervention significantly improved the average diastolic blood pressure of hypertensive patients (n = 50) three months into treatment (98 mmHg at baseline vs. 86 mmHg in Month 3, P = 0.001). However, health systems barriers typical of fragile settings, such as cost of transport and medication for patients and lack of supply of medications and treatment equipment in facilities, hindered the optimal delivery of care for hypertensive and diabetic patients. Conclusion Our study suggests the potential feasibility of this approach to strengthening primary care delivery of NCDs in fragile contexts. However, the approach needs to be built into routine supervision and pre-service training to be sustained. Key barriers in the health system and at community level also need to be addressed

L-Carnitine counteracts in vitro fructose-induced hepatic steatosis through targeting oxidative stress markers

Purpose: Nonalcoholic fatty liver disease (NAFLD) is defined by excessive lipid accumulation in the liver and involves an ample spectrum of liver diseases, ranging from simple uncomplicated steatosis to cirrhosis and hepatocellular carcinoma. Accumulating evidence demonstrates that high fructose intake enhances NAFLD development and progression promoting inhibition of mitochondrial \u3b2-oxidation of long-chain fatty acids and oxidative damages. l-Carnitine (LC), involved in \u3b2-oxidation, has been used to reduce obesity caused by high-fat diet, which is beneficial to ameliorating fatty liver diseases. Moreover, in the recent years, various studies have established LC anti-oxidative proprieties. The objective of this study was to elucidate primarily the underlying anti-oxidative mechanisms of LC in an in vitro model of fructose-induced liver steatosis. Methods: Human hepatoma HepG2 cells were maintained in medium supplemented with LC (5 mM LC) with or without 5 mM fructose (F) for 48 h and 72 h. In control cells, LC or F was not added to medium. Fat deposition, anti-oxidative, and mitochondrial homeostasis were investigated. Results: LC supplementation decreased the intracellular lipid deposition enhancing AMPK activation. However, compound C (AMPK inhibitor-10 \u3bcM), significantly abolished LC benefits in F condition. Moreover, LC, increasing PGC1 \u3b1 expression, ameliorates mitochondrial damage-F induced. Above all, LC reduced ROS production and simultaneously increased protein content of antioxidant factors, SOD2 and Nrf2. Conclusion: Our data seemed to show that LC attenuate fructose-mediated lipid accumulation through AMPK activation. Moreover, LC counteracts mitochondrial damages and reactive oxygen species production restoring antioxidant cellular machine. These findings provide new insights into LC role as an AMPK activator and anti-oxidative molecule in NAFLD