In vitro adhesion and anti-inflammatory properties of Limosilactobacillus fermentum FS-10 isolated from infant fecal sample / Adhesión in vitro y propiedades antiinflamatorias de Limosilactobacillus fermentum FS-10 aislado de muestra fecal infantil

In this study, seven strains of Limosilactobacillus fermentum were isolated from an infant fecal sample and characterized using in vitro studies. Lactobacillus rhamnosus GG was used as a comparison because it is a well-documented commercial probiotic. The isolates were tested for attributes such as acid and phenol tolerance, bile salt hydrolase (BSH) activity, and antibiotic sensitivity. One isolate, L. fermentum FS-10, displayed enhanced cell surface hydrophobicity (> 85%) and mucin adhesion. Mucin-binding helps colonization in the gut. The immunomodulatory property of L. fermentum FS-10 was evaluated by determining the modulation of pro- and anti-inflammatory factors such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-10, and nitric oxide (NO) in human acute monocytic leukemia (THP-1) cells under inflammatory conditions induced by lipopolysaccharide (LPS). L. fermentum FS-10 potently downregulated the expression of TNF-α and nitric oxide and upregulated IL-10 levels, indicating an anti-inflammatory response. Safety assessment of the strain revealed the absence of genes for virulence factors, toxin production, and antibiotic resistance, potentiating application as a probiotic strain.(AU)

In vitro adhesion and anti-inflammatory properties of Limosilactobacillus fermentum FS-10 isolated from infant fecal sample.

In this study, seven strains of Limosilactobacillus fermentum were isolated from an infant fecal sample and characterized using in vitro studies. Lactobacillus rhamnosus GG was used as a comparison because it is a well-documented commercial probiotic. The isolates were tested for attributes such as acid and phenol tolerance, bile salt hydrolase (BSH) activity, and antibiotic sensitivity. One isolate, L. fermentum FS-10, displayed enhanced cell surface hydrophobicity (> 85%) and mucin adhesion. Mucin-binding helps colonization in the gut. The immunomodulatory property of L. fermentum FS-10 was evaluated by determining the modulation of pro- and anti-inflammatory factors such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-10, and nitric oxide (NO) in human acute monocytic leukemia (THP-1) cells under inflammatory conditions induced by lipopolysaccharide (LPS). L. fermentum FS-10 potently downregulated the expression of TNF-α and nitric oxide and upregulated IL-10 levels, indicating an anti-inflammatory response. Safety assessment of the strain revealed the absence of genes for virulence factors, toxin production, and antibiotic resistance, potentiating application as a probiotic strain.

COVID-19 Disease in Under-5 Children: Current Status and Strategies for Prevention including Vaccination.

Since the coronavirus disease (COVID-19) pandemic hit the globe in early 2020, we have steadily gained insight into its pathogenesis; thereby improving surveillance and preventive measures. In contrast to other respiratory viruses, neonates and young children infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) have a milder clinical presentation, with only a small proportion needing hospitalization and intensive care support. With the emergence of novel variants and improved testing services, there has been a higher incidence of COVID-19 disease reported among children and neonates. Despite this, the proportion of young children with severe disease has not increased. Key mechanisms that protect young children from severe COVID-19 disease include the placental barrier, differential expression of angiotensin-converting enzyme 2 (ACE-2) receptors, immature immune response, and passive transfer of antibodies via placenta and human milk. Implementing mass vaccination programs has been a major milestone in reducing the global disease burden. However, considering the lower risk of severe COVID-19 illness in young children and the limited evidence about long-term vaccine safety, the risk-benefit balance in children under five years of age is more complex. In this review, we do not support or undermine vaccination of young children but outline current evidence and guidelines, and highlight controversies, knowledge gaps, and ethical issues related to COVID-19 vaccination in young children. Regulatory bodies should consider the individual and community benefits of vaccinating younger children in their local epidemiological setting while planning regional immunization policies.

Clinical characteristics & outcome of SARS-CoV-2 infected neonates presenting to paediatric emergency.

Background & objectives: Data on neonatal COVID-19 are limited to the immediate postnatal period, with a primary focus on vertical transmission in inborn infants. This study was aimed to assess the characteristics and outcome of COVID-19 in outborn neonates. Methods: All neonates admitted to the paediatric emergency from August 1 to December 31, 2020, were included in the study. SARS-CoV-2 reverse transcription- (RT)-PCR test was done on oro/nasopharyngeal specimens obtained at admission. The clinical characteristics and outcomes of SARS-CoV-2 positive and negative neonates were compared and the diagnostic accuracy of a selective testing policy was assessed. Results: A total of 1225 neonates were admitted during the study period, of whom SARS-CoV-2 RT-PCR was performed in 969. The RT-PCR test was positive in 17 (1.8%). Mean (standard deviation) gestation and birth weight of SARS-CoV-2-infected neonates were 35.5 (3.2) wk and 2274 (695) g, respectively. Most neonates (11/17) with confirmed COVID-19 reported in the first two weeks of life. Respiratory distress (14/17) was the predominant manifestation. Five (5/17, 29.4%) SARS-CoV-2 infected neonates died. Neonates with COVID-19 were at a higher risk for all-cause mortality [odds ratio (OR): 3.1; 95% confidence interval (CI): 1.1-8.9, P=0.03]; however, mortality did not differ after adjusting for lethal malformation (OR: 2.4; 95% CI: 0.7-8.7). Sensitivity, specificity, accuracy, positive and negative likelihood ratios (95% CI) of selective testing policy for SARS-CoV-2 infection at admission was 52.9 (28.5-76.1), 83.3 (80.7-85.6), 82.8 (80.3-85.1), 3.17 (1.98-5.07), and 0.56 (0.34-0.93) per cent, respectively. Interpretation & conclusions: SARS-CoV-2 positivity rate among the outborn neonates reporting to the paediatric emergency and tested for COVID-19 was observed to be low. The selective testing policy had poor diagnostic accuracy in distinguishing COVID-19 from non-COVID illness.

Microbial fermentation of Fossence™, a short-chain fructo-oligosaccharide, under simulated human proximal colonic condition and assessment of its prebiotic effects-a pilot study.

A short-chain fructo-oligosaccharide (sc-FOS) was tested in a simulator of the human gut microbial ecosystem (SHIME) in vitro model to quantify its prebiotic effects according to Prebiotic Index (PI) and Measure of prebiotic effect (MPE) equations. FossenceTM, (sc-FOS, 0.5%) was fermented in a simulated human proximal colonic condition, using a fecal inoculum from a healthy individual. We analysed the pH reduction, substrate utilization, lactate and short-chain fatty acid (SCFA) production and microbial community modulation. Microbial fermentation of sc-FOS strongly reduced the media pH indicating the production of lactate and SCFA with accumulation of lactate and enhanced levels of acetate (34.38 ± 0.38 mM), propionate (20.93 ± 0.56 mM) and butyrate (4.93 ± 0.03 mM) compared to 18.46 ± 0.20 mM, 6.24 ± 0.10 mM and 3.3 ± 0.06 mM in the blank, respectively. Total SCFA production in test media was 61.91 ± 0.87 mM compared to 33.65 ± 0.36 mM in blank and the contribution of free-sugars present in sc-FOS to SCFAs was negligible. Modulation of the microbial community was analysed through 16S rRNA sequencing and we found that sc-FOS greatly stimulated the beneficial bacteria such as Bifidobacteria and Lactobacillus. We report the PI and MPE values for FossenceTM, as 14.9 and 0.01 respectively at the end of 24 h, which is an indicator of a strong prebiotic effect.

Expression dynamics of the poly-γ-glutamic acid biosynthesis genes of Bacillus subtilis in response to glucose and glutamic acid-a pilot study.

Poly-γ-glutamic acid (PGA) is biosynthesized by various Bacillus species through PGA synthetase, encoded by the PGA operon comprised of the ywsC and ywtABC genes. Due to the minimal available knowledge, understanding the expression pattern of PGA operon genes is pivotal. In this study, the effect of glucose and glutamic acid on the global gene expression profile of Bacillus subtilis Natto3 was investigated using high throughput microarray, with an emphasis on the PGA operon and genes influencing PGA production. Two treatment groups (set1-in the presence of glutamic acid and set2-in the presence of glutamic acid + glucose) were analyzed against the control (in the presence of glucose). In the microarray, both the groups showed a trend of up-regulation for ywsC and ywtA genes (log2 fold change of 0.55, P = 0.0194, 0.92, P = 0.0069 in set1 and 0.78, P = 0.0023, 0.59, P = 0.0172 in set2, respectively) and down-regulation of ywtB and ywtC genes (log2 fold change of -1.83, P = 0.0001, -1.42, P = 0.0017 in set1 and -1.52, P = 0.0012, -0.55, P = 0.1112 in set2, respectively), supporting the indispensability of the ywsC and ywtA genes in PGA production. Interestingly, the ywtB and ywtC genes, belonging to the same operon, were down-regulated in both the conditions (set1 and set2). To the best of our knowledge, this expression pattern of PGA operon genes is a unique observation.

Targeted therapy of chronic liver diseases with the inhibitors of angiogenesis.

Angiogenesis appears to be intrinsically associated with the progression of chronic liver diseases, which eventually leads to the development of cirrhosis and related complications, including hepatocellular carcinoma. Several studies have suggested that this association is relevant for chronic liver disease (CLD) progression, with angiogenesis. The fact that angiogenesis plays a pivotal role in CLDs gives rise to new opportunities for treating CLDs. Inhibitor of angiogenesis has proved effective for the treatment of patients suffering from CLD. However, it is limited in diagnosis. The last decade has witnessed a plethora of publications which elucidate the potential of angiogenesis inhibitors for the therapy of CLD. The close relationship between the progression of CLDs and angiogenesis emphasizes the need for anti-angiogenic therapy to block/slow down CLD progression. The present review summarizes all these discussions, the results of the related studies carried out to date and the future prospects in this field. We discuss liver angiogenesis in normal and pathophysiologic conditions with a focus on the role and future use of angiogenic factors as second-line treatment of CLD. This review compiles relevant findings and offers opinions that have emerged in last few years relating liver angiogenesis and its treatment using anti-angiogenic factors.

Selection of an Effective Indicator for Rapid Detection of Microorganisms Producing γ-Polyglutamic Acid and Its Biosynthesis Under Submerged Fermentation Conditions Using Bacillus methylotrophicus.

γ-Polyglutamic acid (γ-PGA) is a biosynthetic outcome of glutamic acid polymerization by microbes. In the current study, we have isolated Bacillus methylotrophicus on solid differential media containing methylene blue. This is the first report mentioning the use of methylene blue to distinguish the monomeric and polymeric form of glutamic acid in the liquid medium using UV-Vis spectrophotometer. Our method can simplify the analytical process of γ-PGA confirmation using the aforementioned studies. This screening protocol is sensitive to the detection of γ-PGA quantities as low as 3 µg/mL; thus, the potent producers can be effectively screened. Furthermore, we have carried out process optimization of the present strain for γ-PGA production wherein we could obtain 1.4-fold improvement in the yield with respect to utilization of carbon source and 2.6-fold increase with respect to nitrogen source under submerged fermentation at a shake flask level. We have shown an increase in γ-PGA titer from 1.5 to 36 g/L using mannitol, monosodium glutamate, peptone, and tween 20.

Effect of secondary metabolite of Actinidia deliciosa on the biofilm and extra-cellular matrix components of Acinetobacter baumannii.

Acinetobacter baumannii, opportunistic nosocomial pathogen, increases gradually in the clinical setup. The high level of resistance mechanisms acquired by these bacteria makes their eradication difficult and biofilm formation is one of them. Biofilm comprises of closely packed bacterial population crowded together by extra-cellular matrix (ECM). ECM contains bacterial secreted polymers such as exopolysaccharides (EPS), proteins and extracellular-DNA (e-DNA) and rarely amyloidogenic proteins. Biofilm offers protection of underlying bacterial population against chemotherapeutic agents and host immune system. Therefore, present efforts are focused to find a novel therapeutic that targets biofilm-associated infections. Plants are used as a natural therapeutic for numerous ailments. In order to find an alternative of the available antibacterial drugs, we have focused on the natural herbal active compounds. In this study, we have extracted active compounds from various medicinal plants and screened its anti-biofilm activity against carbapenem resistant strain of A. baumannii. Results showed that polar extract of kiwi (Actinidia deliciosa) and clove (Syzygium aromaticum) exhibit effective anti-biofilm activity. These two plants were also used for their phytochemical screening and TLC profiling to find out the constituting secondary metabolites. Actinidia deliciosa extract contains an alkaloid (sanquinarine) as well as a flavonoid (hydroxyflavone). Anti-biofilm effect of this extract on the ECM of A. baumannii showed that it reduces EPS, protein and eDNA contents in the ECM. Proteins of ECM have also shown to form amyloid like structure, which was evident from its interaction with the Congo Red. CFU counting after Actinidia deliciosa extract treatment also supported the results. Therefore, it can be concluded that polar extract of A. deliciosa can be used to find suitable alternative therapeutic to control biofilm formation by carbapenem resistant strain of Acinetobacter baumannii.