Utilization of non-pathogenic bacteria to obtain optimum biofilm production for beneficial applications.

Depending on the bacteria embedded in the extracellular polymeric layer, biofilms can be advantageous or harmful. The isolated strains used in this investigation are already established to be beneficial biofilm-producing bacteria. In order to use them effectively in various domains, it is necessary to characterize them and understand their ideal physiological characteristics for maximum biofilm growth. This study used genome sequence analysis to identify and characterize strains isolated from water samples in Raipur, Chhattisgarh, India. The nucleotide sequences were submitted to NCBI GenBank under the accession numbers Bacillus tequilensis (MN889418) and Pseudomonas beteli (MN889419) and the strains were further characterized using some advanced techniques (phase contrast microscopy, Raman spectroscopy, Fourier-transform infrared spectroscopy, and scanning electron microscope). For maximum biofilm formation by isolated bacterial strains, many physiochemical factors including incubation duration, temperature, pH, carbon source concentration, and nitrogen source concentration were further examined and optimized. The fact that these non-pathogenic strains were found in public water supplies is another important part of this research because there is a chance that they could change into pathogenic state in future and cause disease in humans.

The investigation of the physiochemical factors and bacterial communities indicates a low-toxic infectious risk of the Qiujiang River in Shanghai, China.

The overall water quality of urban rivers is closely related to the community structure and the physiochemical factors in them. In this study, the bacterial communities and physiochemical factors of the Qiujiang River, an important urban river in Shanghai, were explored. Water samples were collected from nine sites of the Qiujiang River on November 16, 2020. The water quality and bacterial diversity were studied through physicochemical detection, microbial culture and identification, luminescence bacteria method, and 16S rRNA Illumina MiSeq high-throughput sequencing technology. The water pollution of the Qiujiang River was quite serious with three water quality evaluation indexes, including Cd2+, Pb2+, and NH4+-N, exceeding the Class V standard set by the Environmental Quality Standards for Surface Water (China, GB3838-2002), while the luminescent bacteria test indicated low toxicity of nine sampling sites. Through 16S rRNA sequencing, a total of 45 phyla, 124 classes, and 963 genera were identified, in which Proteobacteria, Gammaproteobacteria, and Limnohabitans were the most abundant phylum, class, and genus, respectively. The Spearman correlation heatmap and redundancy analysis showed that the bacterial communities in the Qiujiang River were correlated with pH; the concentrations of K+, and NH4+-N, and the Limnohabitans were significantly correlated with the concentrations of K+, and NH4+-N in the Zhongyuan Road bridge segment. In addition, opportunistic pathogens Enterobacter cloacae complex and Klebsiella pneumoniae in the samples collected in the Zhongyuan Road bridge segment and Huangpu River segment, respectively, were successfully cultured. The Qiujiang River was a heavily polluted urban river. The bacterial community structure and diversity were greatly affected by the physiochemical factors of the Qiujiang River, and it displayed low toxicity while a relatively high infectious risk of intestinal and lung infectious diseases.

Correlation of caries occurrence in primary teeth using human leukocyte antigen typing and maternal and physiochemical factors.

Background: Dental caries being the leading health issue worldwide has no specific cure due to its multifactorial etiology and genetic susceptibility. Hence, this paper attempted to correlate the clinical and hereditary factors between mother and child, to predict the caries occurrence in child in future, and thereby implement early preventive measures. Aim: The aim of the study was to look for an association between maternal and child's human leukocyte antigen (HLA)-DR4 levels and relate it with other physiochemical factors to assess caries susceptibility in children. Methodology: Saliva samples were collected from children who were in the age group of 0-6 years and their mothers by spitting method and swab method. The clinical indicators such as Decayed, Missing, and Filled Teeth, decayed, extraction needed, and filled teeth, salivary flow rate, and pH were recorded by clinical evaluation. The Streptococcus mutans count was measured by culture plate followed by colony count method, and the HLA-DR4 factor was assessed using ELISA. Results: The results revealed a statistically significant correlation between the physiochemical factors of the mother and the child. The genetic factor in which the HLA-DR4 caries indicator was checked also has a strong association between the mother and the offspring. Thus, a strong caries prediction formula was derived through which probability of caries occurrence in the child could be determined prematurely. Conclusion: Thus, it can be concluded that using the clinical and genetic factors, the caries prediction can be done for the child and preventive protocol can be started before disease occurrence.

Factors influencing the mechanical stability of alginate beads applicable for immunoisolation of mammalian cells.

Transplantation of microencapsulated cells has been proposed as a cure for many types of endocrine disorders. Alginate-based microcapsules have been used in many of the feasibility studied addressing cure of the endocrine disorders, and different cancer types. Despite years of intensive research it is still not completely understood which factors have to be controlled and documented for achieving adequate mechanical stability. Here we studied the strength and elasticity of microcapsules of different composition with and without cell load. We compared strength (force) versus elasticity (time) required to compress individual microcapsule to 60% deformation. It is demonstrated that the alginate viscosity, the size of the beads, the alginate type, the gelling time, the storage solution and the cell load are dominant factors in determining the final strength of alginate-based microcapsules while the type of gelling ion, the polyamino acid incubation time, the type of polyamino acid and the culturing time determines the elasticity of the alginate-based microcapsules. Our data underpin the essence of documenting the above mentioned factors in studies on encapsulated cells as mechanical stability is an essential factor in the success and failure of encapsulated grafts.