35 research outputs found
High-throughput sequencing of SARS-CoV-2 in wastewater provides insights into circulating variants
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) likely emerged from a zoonotic spill-over event and has led to a global pandemic. The public health response has been predominantly informed by surveillance of symptomatic individuals and contact tracing, with quarantine, and other preventive measures have then been applied to mitigate further spread. Non-traditional methods of surveillance such as genomic epidemiology and wastewater-based epidemiology (WBE) have also been leveraged during this pandemic. Genomic epidemiology uses high-throughput sequencing of SARS-CoV-2 genomes to inform local and international transmission events, as well as the diversity of circulating variants. WBE uses wastewater to analyse community spread, as it is known that SARS-CoV-2 is shed through bodily excretions. Since both symptomatic and asymptomatic individuals contribute to wastewater inputs, we hypothesized that the resultant pooled sample of population-wide excreta can provide a more comprehensive picture of SARS-CoV-2 genomic diversity circulating in a community than clinical testing and sequencing alone. In this study, we analysed 91 wastewater samples from 11 states in the USA, where the majority of samples represent Maricopa County, Arizona (USA). With the objective of assessing the viral diversity at a population scale, we undertook a single-nucleotide variant (SNV) analysis on data from 52 samples with \u3e90% SARS-CoV-2 genome coverage of sequence reads, and compared these SNVs with those detected in genomes sequenced from clinical patients. We identified 7973 SNVs, of which 548 were “novel” SNVs that had not yet been identified in the global clinical-derived data as of 17th June 2020 (the day after our last wastewater sampling date). However, between 17th of June 2020 and 20th November 2020, almost half of the novel SNVs have since been detected in clinical-derived data. Using the combination of SNVs present in each sample, we identified the more probable lineages present in that sample and compared them to lineages observed in North America prior to our sampling dates. The wastewater-derived SARS-CoV-2 sequence data indicates there were more lineages circulating across the sampled communities than represented in the clinical-derived data. Principal coordinate analyses identified patterns in population structure based on genetic variation within the sequenced samples, with clear trends associated with increased diversity likely due to a higher number of infected individuals relative to the sampling dates. We demonstrate that genetic correlation analysis combined with SNVs analysis using wastewater sampling can provide a comprehensive snapshot of the SARS-CoV-2 genetic population structure circulating within a community, which might not be observed if relying solely on clinical cases
Bacterial sialoglycosidases in Virulence and Pathogenesis
Human oral microbiome and dysbiotic infections have been recently evidently identified. One of the major reasons for such dysbiosis is impairment of the immune system. Periodontitis is a chronic inflammatory disease affecting the tissues that surround and support the teeth. In the United States., approximately 65 million people are affected by this condition. Its occurrence is also associated with many important systemic diseases such as cardiovascular disease, rheumatoid arthritis, and Alzheimer’s disease. Among the most important etiologies of periodontitis is Porphyromonas gingivalis, a keystone bacterial pathogen. Keystone pathogens can orchestrate inflammatory disease by remodeling a normally benign microbiota causing imbalance between normal and pathogenic microbiota (dysbiosis). The important characteristics of P. gingivalis causing dysbiosis are its virulence factors which cause effective subversion of host defenses to its advantage allowing other pathogens to grow. Some of the mechanisms involved in these processes are still not well-understood. However, various microbial strategies target host sialoglycoproteins for immune dysregulation. In addition, the enzymes that break down sialoglycoproteins and sialoglycans are the “sialoglycoproteases„, resulting in exposed terminal sialic acid. This process could lead to pathogen-toll like receptor (TLR) interactions mediated through sialic acid receptor ligand mechanisms. Assessing the function of P. gingivalis sialoglycoproteases, could pave the way to designing carbohydrate analogues and sialic acid mimetics to serve as drug targets
Fabrication of cylindrical bone graft substitute supported by reduced graphene-oxide and nanocurcumin to promotes the bone tissue development
In this study, a prototype technique was used to develop cylindrical bone graft substitute (C-BGS) from gelatin (GEL) derived from fish skin, demineralized bone matrix (DBM) from fishbone, reduced graphene oxide (R-GO), and nanocurcumin (Nano-Cu) for their potential application in bone graft substitute. The impact of the inclusion of R-GO and Nano-Cu on the physicochemical characteristics, antibacterial, and in vitro properties of the C-BGS was assessed. The C-BGS showed compressive strength of 13.64 +/- 0.20 (MPa) and elongation at break (%) of 23.76 +/- 0.20. The antibacterial activity of C-BGS against E.coli and S.aureus was excellent. In vitro study, revealed 98% cell viability on the C-BGS. The C-BGS with physicochemical, antibacterial, and biocompatibility properties can tried as a bone graft substitute material.[118C350]Acknowledgments The award of TUBITAK 2232-International Fellowship for Outstanding Researcher (Project No: 118C350) to Dr. Rethinam Senthil is greatfully acknowledge
Functionalized electrospun nanofibers for high efficiency removal of particulate matter
In recent years, introducing electrospun airfilters to enhance the removal of PM2.5 and PM10-2.5 has received much interest. In this study, a novel poly-(vinyl) alcohol (PVA)/carbon nanopArticle (CNP)/tea leaf extract (TLE), functionalized nanofibrous air filter (FNA) was fabricated using an electrospinning method. Novelty of the unique work in the blending of CNP and TLE, first of its kind, for the preparation of FNA. Polysaccharide crosslinked FNA has a carbon complex with two monosaccharide units to produce the intrinsic properties of the PM2.5 and PM10-2.5 removal efficiency. The FNA had promising traits of UV protection. The prepared FNA was characterized using physicochemical, mechanical, antimicrobial activity, etc., in addition to its PM2.5 and PM10-2.5 removal efficiency. Pore size and distribution study using the capillary flow porometry method has proved the structure of FNA. FNA exhibited excellent low pressure drop (110 Pa), which are promising characteristics for air purification. FNA from PVA: CNP: TLE exhibited high PM2.5 and PM10-2.5 removal efficiencies of 99.25% and 99.29%, respectively. Hence, the study proved.2232-International Fellowship for Outstanding Researcher Program of TUBITAK (Project No: 118C350).TUBITAK [118C350
Characterization of Changes due to pH Variations in Beta Peptide ((25-35)) Leading to Alzheimer's Disease
Rajendran, Thirugnanasambandam/0000-0001-8158-9133; Rajendran, Thirugnanasambandam/0000-0001-8158-9133;WOS: 000498986900001The effect of various concentrations of amyloid beta peptide (ABP) in different pH (pH 2, 6, 7, 8, 10) in aging at different time intervals was analysed using various techniques. the pH 7.4 and 8 were compared with other pH solution which indicated that the secondary structure content with high beta-sheet conformation is found at pH 7.4 and 8. Phosphate buffer solutions (pH) were detected using CD spectroscopy. the CD spectra of peptide in phosphate buffer (pH 2 and 10) on aging at time intervals were also analysed with the aging of sample (pH 2) on the 10th day. the results showed no major secondary structural changes in the peptide, which was indicative predominant random coil structure. the phosphate buffer pH 6, 7.4, 8 on the 10th day showed the occurrence of crossover point. This same sample smear on slide was mounded and the fibrils were visualized using the light microscope. the percent of viable cell in different pH was detected in MTT (3-(4,5-Dimethyazol-2-yl)-2, 5-diphenyl-tetrazolium bromide) assay using human keratinocyte cell line (HaCaT). Fluorescence spectroscopy was used to study the growth and development of fibrils
Preparation of biocompatible polymeric bio-scaffold as wound healing activity: Characterization and In vivo analysis
In this study, a combination of collagen (CL), gelatin (GL) and squid ink (SI) were used to produce a biocompatible polymeric bio-scaffold (CL, CL: GL and CL: GL: SI) was examined for wound healing purposes. Biocompatible polymeric bio-scaffold (BPBS) plays an important role in wound care due to their cost-effective, good mechanical properties, bio-compatible and antimicrobial characteristics. Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) of the BPBS has showed the heat stability and nature of samples, respectively, and while scanning electron microscopy (SEM) images revealed the blending of CL fiber, GL, and SI pattern interface. BPBS displayed excellent antimicrobial activity against both E.coli and S.aureus. The inhibition zone of BPBS results obtained in 4.57 +/- 0.30 mm against E.coli and 4.74 +/- 0.15 mm against S.aureus. Mechanical characteristics of BPBS shows tensile strength of 20.88 +/- 0.05 (Mpa), 17.74 +/- 0.05 (%) as Elongation at break, 26.31 +/- 0.21 (%) of flexibility and water absorption of 29.80 +/- 0.05 (%). Invitro analysis of CL: GL: SI, displayed 100% biocompatibility and cell viability was found 3rd days. In vivo study using mice by excisional animal model examined the CL: GL: SI scaffold can significantly accelerate the process of wound healing.Dr. Senthil Rethinam acknowledges the funding support granted by the 2232International Fellowship for Outstanding Researcher Program of TUBITAK, Turkey, (Project No: 118C350) .TUBITAK, Turkey [118C350
Electrospun nano-bio membrane for bone tissue engineering application-a new approach
WOS: 000540352000036The aim of this research study, develop electrospun nano-bio membrane (ENBM) from Poly (vinyl) alcohol (PVA), nano-Demineralized Bone Matrix (nano-DBM) and to impart additional strength, incorporation of carbon nanoparticles (CNP) by elctrospinning machine for their potential application in bone tissue regeneration. the effective of ENBM for biocompatibility properties were evaluated using MG 63 osteoblast cell line, which showed 100% biocompatibility and more viable cell present in the electrospun nano-biomembrane. in vitro biomineralization, more apatite formation was observed SEM images. Electrospun nanoscaffold prepared using PVA, nano-DBM and CNP (0.6%) possessed improved mechanical properties viz. 14.58 +/- 0.13 Mpa of tensile strength, 13.87 +/- 0.05% of elongation at break and 36.84 +/- 0.11% water absorption. This research study proved the bone formation of these ENBM in bone tissue regeneration and regenerative medicine.2232-International Fellowship for Outstanding Researcher Program of TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [118C350]Dr. Senthil Rethinam (Project Coordinator) acknowledges the funding support granted by the 2232-International Fellowship for Outstanding Researcher Program of TUBITAK (Project No: 118C350)