Isolation and characterization of exopolysaccharide derived from Lacticaseibacillus paracasei AS20(1) with probiotic potential and evaluation of its antibacterial activity.

This study was done to find exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) against foodborne pathogens. Isolated LAB were screened to find the ones with the ability to produce antibacterial EPS against foodborne pathogens. Among tested EPSs, EPS of AS20(1) isolate showed inhibitory effects on the growth of Listeria monocytogenes (MIC = 0·935 mg ml-1 , MBC = 0·935 mg ml-1 ), Yersinia enterocolitica (MIC = 12·5 mg ml-1 , MBC = 50 mg ml-1 ) and Bacillus cereus (MIC = 6·25 mg ml-1 , MBC = 12·5 mg ml-1 ). According to 16S rRNA sequencing, AS20(1) showed the closest similarity to Lacticaseibacillus paracasei (100%). This antibacterial EPS showed negligible toxicity (4·4%-5·2%) against red blood cells. Lacticaseibacillus paracasei AS20(1) showed probiotic properties, including high acid resistance, hydrophobicity (47·5%), autoaggregation and coaggregation with foodborne pathogens. Also, L. paracasei AS20(1) showed no haemolysis activity and antibiotic resistance. Characterization of antibacterial EPS revealed that it is a heteropolysaccharide with various functional groups, amorphous structure, and smooth surface, sheet and compact structure, which can be suitable for food packaging. L. paracasei AS20(1) and its antimicrobial EPS can be used to make functional food.

All roads can lead to surgery.

Pursuing a career in surgery is a rigorous process that demands commitment and hard work. Surgeons in the United Kingdom must go overcome a myriad of competitive stages prior to becoming a consultant. In the United Kingdom, the most common pathway to become a surgeon is via the 'direct route' which encompasses completing multiple training programs, namely, the Foundation Program, followed by Core Surgical Training, and then onto Higher Speciality Training, with the aim of obtaining the Certificate of Completion of Training (CCT). More recently, certain specialities have introduced the 'Improving Surgical Training' (IST) pathway. IST is a competence-based, run through surgical program that was introduced by the Royal College of Surgeons of England (RCS) and Health Education England (HEE). "The pilot trials improvements in the quality of training, a better balance between service and training for trainees, and professionalisation of the role of the surgical trainers" [1]. However, there are alternative pathways that have been designed for those who prefer a different route to training or have been unsuccessful during the selection stages. These pathways are not well-advertised, but with the competitive rates now higher than before, it is becoming a more attractive pathway for junior doctors, hence the increasing the demand for clearer instructions on potential routes for aspiring surgeons.

Physical activity during COVID-19 pandemic in the Iranian population: A brief report.

COVID-19 pandemic and restrictive public health measures due to it can have many effects on physical activity. Our study aimed to compare the levels of physical activity levels (expressed as MET-minute/week), among Qom city (Iran) adults in pre and during the COVID-19 pandemic (January 2020 and 20 to 29 May 2020, respectively). 670 adults were included in this study and grouped based on age and gender. The short-form International physical activity questionnaire (IPAQ, SF) was distributed to the participants through an online survey. The Wilcoxon signed-rank test was used for statistical analyses. The present study showed that the level of physical activity decreased significantly during COVID-19 compared to pre-COVID-19 in both sexes and age groups (p < 0.001). Also, this study found that a total of 78% of the participants did not meet the physical activity guidelines during COVID-19 in Iran. Our results indicate the necessity to consider an integrated and comprehensive approach to reduce the inactivity caused by COVID-19.

Isolation and screening of rare Actinobacteria, a new insight for finding natural products with antivascular calcification activity.

AIM: Vascular calcification (VC) is a significant pathological process in some life-threatening diseases. Several pathological mechanisms, including transdifferentiation of vascular smooth muscle cells to osteoblast-like cells and apoptosis are involved in VC. Compounds with an inhibitory effect on these processes are potentially efficient medications. In consideration of the multiple biological activities of Actinobacteria, this research was aimed at finding anti-VC metabolite-producing Actinobacteria. METHODS AND RESULTS: After the isolation and identification of Actinobacteria, the effect of their fermentation broth extracts on the apoptosis rate was measured using various methods, for example, ethidium bromide/acridine orange staining, DNA laddering and diphenylamine assays. The effect of the most effective fermentation broth extract of Actinobacteria (FBEA) on the mRNA expression of runt-related transcription factor 2 (Runx2) and osteopontin (OPN) was examined. Finally, the most effective FBEA was fractionated and the chemical composition of anti-VC fractions was analysed using GC-MS. Various VC inhibition rates were observed in the tested FBEA (20 µg ml-1 ; 17·9-60·15%). The inhibition of DNA fragmentation was 7-48%. The FBE with the greatest anticalcification activity belonged to Kribbella sp. UTMC 267 and, according to 16S rRNA analysis, Kribbella sancticallisti with a similarity of 98·53% is its nearest neighbour. The FBE of Kribbella sp. UTMC 267 reduced Runx2 mRNA expression by 2·95-fold and OPN mRNA expression by 28·57-fold, both of which are considered significant (P < 0·05). Finally, GC-MS analysis showed the existence of potent anti-oxidative and anti-inflammation agents in FBE of Kribbella sp. UTMC 267. CONCLUSIONS: Actinobacterial metabolites can provide a new strategy for treating VC diseases by reducing the expression of osteogenic genes, the apoptosis rate and oxidative stress. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights the therapeutic potential of Kribbella sp. metabolites and Actinobacteria as a new natural source for drug discovery programs in the nonantibiotic bioactivity field.

Simultaneous anti-diabetic and anti-vascular calcification activity of Nocardia sp. UTMC 751.

Alpha-amylase can act as a significant player in causing hyperglycaemia, leading to protein glycation, which is the main complication in this condition, besides causing vascular calcification (VC), an important vascular failure caused due to this. In order to find a natural source of the biocompounds with inhibitory effects on α-amylase, 15 fermentation broth extracts of actinobacteria (FBEA) (200 µg ml-1 ) have been screened. Finally, the effects of the most efficient FBE have been investigated on osteopontin (OPN, a VC marker) mRNA level in the vascular smooth muscle cells under the calcification conditions, and the chemical constituents of the most efficient FBE were analysed using gas chromatography and mass spectrometry (GC-MS) analysis. The tested FBEA showed anti-amylase (7·2-21%) and anti-denaturation (7·5-37%) activities. Among the tested FBEA, Nocardia sp. UTMC 751 FBE showed the highest anti-amylase activity (21%). This treatment group also displayed the minimum fructosamine and the maximum thiol groups content. In addition, this FBE reduced the mRNA level of the OPN (fourfold). The GC-MS analysis demonstrated the existence of three volatile and known antioxidants including pyrrolo[1,2-a]pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl)-, pyrrolo[1,2-a]pyrazine-1,4-dione, hexahydro-3-(phenylmethyl)- and methyl ester of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid in the FBE of Nocardia sp. UTMC 751. The results indicated that Nocardia sp. UTMC 751 is a considerable source of bioactive compounds that are effective against the direct and indirect pathological targets involved in diabetes. This study highlights the significant potential of rare Actinomycetes in producing pharmaceutically important biocompounds. SIGNIFICANCE AND IMPACT OF THE STUDY: Actinobacteria are one of the best natural libraries for discovering drugs. Various commercial drugs have been developed against infectious and metabolic disorders from actinobacteria; however, there is no report on their simultaneous inhibitory effect against diabetes, a life-threatening disease, and its related pathological processes, like inflammation and vascular calcification (VC). In this research, after several screening, Nocardia sp. UTMC 751 was introduced as the first microbial source exhibiting a simultaneous inhibitory activity on the targets, including hyperglycaemia and protein glycation, and other involved pathological processes like inflammation and VC.

The fabrication and characterization of barium titanate/akermanite nano-bio-ceramic with a suitable piezoelectric coefficient for bone defect recovery.

In recent years, due to the controllable mechanical properties and degradation rate, calcium silicates such as akermanite (Ca2MgSi2O7) with Ca-Mg and Si- containing bio-ceramics have received much more attention. In addition, the piezoelectric effect plays an important role in bone growth, remodeling and defect healing. To achieve our objective, the porous bioactive nano-composite with a suitable piezoelectric coefficient was fabricated by the freeze-casting technique from the barium titanate and nano-akermanite (BT/nAK) suspension. The highest d33of 4pC/N was obtained for BT90/nAK10. The compressive strength and porosity were for BT75/nAK25 and BT60/nAK40 at the highest level, respectively. The average pore channel diameter was 41 for BT75/nAK25. Interestingly enough, the inter-connected pore channel was observed in the SEM images. There was no detectable transformation phase in the XRD pattern for the BT/nAK composites. The manipulation flexibility of this method indicated the potential for the customized needs in the application of bone substitutes. An ((3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide)) MTT assay indicated that the obtained scaffolds have no cytotoxic effects on the human bone marrow mesenchymal stem cells.

Influence of fuel molecular structure on the volatility and oxidative potential of biodiesel particulate matter.

We have studied the effect of chemical composition of biodiesel fuel on the physical (volatility) and chemical (reactive oxygenated species concentration) properties of nano particles emitted from a modern common-rail diesel engine. Particle emissions from the combustion of four biodiesels with controlled chemical compositions and different varying unsaturation degrees and carbon-chain lengths, together with a commercial diesel, were tested and compared in terms of volatility of particles and the amount of reactive oxygenated species carried by particles. Different blends of biodiesel and petro diesel were tested at several engine loads and speeds. We have observed that more saturated fuels with shorter carbon chain lengths result in lower particle mass but produce particles that are more volatile and also have higher levels of Reactive Oxygen Species. This highlights the importance of taking into account metrics that are relevant from the health effects point of view when assessing emissions from new fuel types.

Molecular aspect on the interaction of zinc-ofloxacin complex with deoxyribonucleic acid, proposed model for binding and cytotoxicity evaluation.

Recently, several studies have shown that the metal-fluoroquinolone complexes have more antibacterial and cytotoxic effects in comparison with free fluoroquinolones. These results may introduce new drugs for chemotherapy with fewer side effects. In this work a bidentated zinc (II) complex with ofloxacin (OZC) was synthesized and cytotoxicity activities and DNA binding of the resulted complex was studied. The in-vitro anti proliferative and cytotoxic effects of the free ofloxacin (OFL) and OZC against MCF-7, CaCo2 and SKNMC cell lines were tested by using Trypan blue and lactate dehyrogenase (LDH) assay methods. Results revealed that the OZC exhibits better anti proliferative and cytotoxic activities as compared with the OFL. This may be due to the more interaction of OZC with DNA. Therefore, the interaction of OZC with DNA was investigated by using voltammetry, UV-Vis, fluorescence, FT-IR and circular dichroism spectroscopy methods, and the equilibrium binding constant (Kb), binding site size, and thermodynamic parameters were measured. The results revealed that the OZC interacts with DNA via two modes: electrostatic and outside hydrogen binding. The proposed DNA binding modes may support the greater in-vitro cytotoxicity of OZC compared to OFL alone.

High tuberculosis treatment success in Kabul, Afghanistan despite high patient transfers out.

The National Tuberculosis (TB) Institute has the highest patient transfer-out rate in Afghanistan, but the result and treatment outcome of transferred patients were unknown in 2009. This operational research investigated the characteristics and treatment outcome of all transferred-out patients living in Kabul province. We analysed the 1-year TB register of the Institute (n = 1180 cases) and visited 24 health centres to review their TB registers. The results show the transfer-out rate was 52.6%. Of the transferred cases, 58.6% were women and 61.8% pulmonary TB cases (smear-positive 70.6%). The arrival rates of transfer-out patients at health centres in Kabul province were 87.6% for both men and women. Males aged 21-40 years were the most likely to be nonarrivals (OR = 8.91; 95% CI: 1.55-66.7). Treatment success rates in female and male patients were 84.4% and 77.5% respectively and default rates were 7.8% and 18.3%. Strategies to reduce the non-arrival to health centres and treatment interruption in male patients aged 20-40 years are warranted.