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As current treatments for Alzheimer's disease (AD) lack disease‐modifying interventions, novel therapies capable of restraining AD progression and maintaining better brain function have great significance. Anti‐inflammatory extracellular vesicles (EVs) derived from human induced pluripotent stem cell (hiPSC)‐derived neural stem cells (NSCs) hold promise as a disease‐modifying biologic for AD. This study directly addressed this issue by examining the effects of intranasal (IN) administrations of hiPSC‐NSC‐EVs in 3‐month‐old 5xFAD mice. IN administered hiPSC‐NSC‐EVs incorporated into microglia, including plaque‐associated microglia, and encountered astrocyte soma and processes in the brain. Single‐cell RNA sequencing revealed transcriptomic changes indicative of diminished activation of microglia and astrocytes. Multiple genes linked to disease‐associated microglia, NOD‐, LRR‐, and pyrin domain‐containing protein 3 (NLRP3)‐inflammasome and interferon‐1 (IFN‐1) signalling displayed reduced expression in microglia. Adding hiPSC‐NSC‐EVs to cultured human microglia challenged with amyloid‐beta oligomers resulted in similar effects. Astrocytes also displayed reduced expression of genes linked to IFN‐1 and interleukin‐6 signalling. Furthermore, the modulatory effects of hiPSC‐NSC‐EVs on microglia in the hippocampus persisted 2 months post‐EV treatment without impacting their phagocytosis function. Such effects were evidenced by reductions in microglial clusters and inflammasome complexes, concentrations of mediators, and end products of NLRP3 inflammasome activation, the expression of genes and/or proteins involved in the activation of p38/mitogen‐activated protein kinase and IFN‐1 signalling, and unaltered phagocytosis function. The extent of astrocyte hypertrophy, amyloid‐beta plaques, and p‐tau were also reduced in the hippocampus. Such modulatory effects of hiPSC‐NSC‐EVs also led to better cognitive and mood function. Thus, early hiPSC‐NSC‐EV intervention in AD can maintain better brain function by reducing adverse neuroinflammatory signalling cascades, amyloid‐beta plaque load, and p‐tau. These results reflect the first demonstration of the efficacy of hiPSC‐NSC‐EVs to restrain neuroinflammatory signalling cascades in an AD model by inducing transcriptomic changes in activated microglia and reactive astrocytes. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) released by human induced pluripotent stem cell-derived neural stem cells (hiPSC-NSCs) are enriched with miRNAs and proteins capable of mediating robust antiinflammatory activity. The lack of tumorigenic and immunogenic properties and ability to permeate the entire brain to incorporate into microglia following intranasal (IN) administrations makes them an attractive biologic for curtailing chronic neuroinflammation in neurodegenerative disorders. We tested the hypothesis that IN administrations of hiPSC-NSC-EVs can alleviate chronic neuroinflammation and cognitive impairments induced by the peripheral lipopolysaccharide (LPS) challenge. Adult male, C57BL/6J mice received intraperitoneal injections of LPS (0.75 mg/kg) for seven consecutive days. Then, the mice received either vehicle (VEH) or hiPSC-NSC-EVs (~ 10 × 109 EVs/administration, thrice over 6 days). A month later, mice in all groups were investigated for cognitive function with behavioral tests and euthanized for histological and biochemical studies. Mice receiving VEH after LPS displayed deficits in associative recognition memory, temporal pattern processing, and pattern separation. Such impairments were associated with an increased incidence of activated microglia presenting NOD-, LRR-, and pyrin domain containing 3 (NLRP3) inflammasomes, elevated levels of NLRP3 inflammasome mediators and end products, and decreased neurogenesis in the hippocampus. In contrast, the various cognitive measures in mice receiving hiPSC-NSC-EVs after LPS were closer to naive mice. Significantly, these mice displayed diminished microglial activation, NLRP3 inflammasomes, proinflammatory cytokines, and a level of neurogenesis matching age-matched naïve controls. Thus, IN administrations of hiPSC-NSC-EVs are an efficacious approach to reducing chronic neuroinflammation-induced cognitive impairments. [ABSTRACT FROM AUTHOR]

Introduction: Extracellular vesicles (EVs) released by human-induced pluripotent stem cell (hiPSC)-derived neural stem cells (NSCs) have robust antiinflammatory and neurogenic properties due to therapeutic miRNAs and proteins in their cargo. Hence, hiPSC-NSC-EVs are potentially an excellent biologic for treating neurodegenerative disorders, including Alzheimer's disease (AD). Methods: This study investigated whether intranasally (IN) administered hiPSCNSC-EVs would quickly target various neural cell types in the forebrain, midbrain, and hindbrain regions of 3-month-old 5xFAD mice, a model of b-amyloidosis and familial AD. We administered a single dose of 25 x 109 hiPSC-NSC-EVs labeled with PKH26, and different cohorts of naïve and 5xFAD mice receiving EVs were euthanized at 45 min or 6 h post-administration. Results: At 45 min post-administration, EVs were found in virtually all subregions of the forebrain, midbrain, and hindbrain of naïve and 5xFAD mice, with predominant targeting and internalization into neurons, interneurons, and microglia, including plaque-associated microglia in 5xFAD mice. EVs also came in contact with the plasma membranes of astrocytic processes and the soma of oligodendrocytes in white matter regions. Evaluation of CD63/CD81 expression with the neuronal marker confirmed that PKH26 + particles found within neurons were IN administered hiPSC-NSC-EVs. At 6 h post-administration, EVs persisted in all cell types in both groups, with the distribution mostly matching what was observed at 45 min post-administration. Area fraction (AF) analysis revealed that, in both naïve and 5xFAD mice, higher fractions of EVs incorporate into forebrain regions at both time points. However, at 45 min post-IN administration, AFs of EVs within cell layers in forebrain regions and within microglia in midbrain and hindbrain regions were lower in 5xFAD mice than naïve mice, implying that amyloidosis reduces EV penetrance. Discussion: Collectively, the results provide novel evidence that IN administration of therapeutic hiPSC-NSC-EVs is an efficient avenue for directing such EVs into neurons and glia in all brain regions in the early stage of amyloidosis. As pathological changes in AD are observed in multiple brain areas, the ability to deliver therapeutic EVs into various neural cells in virtually every brain region in the early stage of amyloidosis is attractive for promoting neuroprotective and antiinflammatory effects. [ABSTRACT FROM AUTHOR]

Background. Although several materials have been used for retrograde filling following apical surgeries, there is no consensus on a single best material. Tricalcium silicate-based types of cement have been developed as root-end filling materials mainly due to tricalcium silicate's hydraulic properties. However, its unfavorable setting characteristics and minimal antimicrobial properties have necessitated the introduction of new additives into the existing commercially available materials. To design an affordable product based on a dicalcium silicate with a shorter set time, minimal cytotoxic complications, and enhanced antibacterial activity, we developed a new endodontic cement from pure raw materials, intending to satisfy the prerequisites of ideal retrograde material. Methods. The composition of the experimental calcium silicate-based cement included the addition of calcium chloride and silver nanoparticles in varying concentrations. Structural characterization was carried out using energy dispersive analysis by X-rays using scanning electron microscope (EDAX SEM) and hydration characteristics were performed using an X-ray diffractometer (XRD). The experimental material was further evaluated for biocompatibility using MTT ([3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide)assay and antibacterial activity was evaluated using an agar diffusion test against Enterococcus faecalis. Results. The structural characterization and hydration characteristics revealed that the experimental cement was dicalcium silicate based with favorable biocompatibility and enhanced antibacterial activity. Tricalcium silicate based mineral trioxide aggregate (MTA) also had favourable biocompatibility, however, its antibacterial activity was significantly decreased when compared to the novel cement. Conclusion. All hydraulic cements that are available in the dental market are predominantly tricalcium silicate-based materials. There has been no evidence in the literature to date wherein it has been explored whether a dicalcium silicate-based hydraulic cement can solely be used in root-end cavities. The findings of the study revealed a dicalcium silicate based retrograde filling material with favourable biocompatibility exhibited immediately as well as in the set samples. Incorporation of silver nanoparticles boosted the antibacterial activity when compared to that of ProRoot MTA. This material could potentially reinstate the usual hype created with tricalcium silicate types of cement since dicalcium silicate cements also exhibit similar properties. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) is a naturally occurring biopolymer, with a remarkable wound healing property. Zinc-oxide non-eugenol is a material widely used for periodontal dressing in dentistry. However, it has been reported that zinc oxide non-eugenol is toxic to osteoblasts and fibroblasts. Hence, the present study aimed to evaluate the drug release and cytotoxicity of HA and zinc-oxide gels. Hydrogels of HA and zinc oxide were formulated with carbopol as a carrier. In vitro drug release was performed by UV spectrophotometry, dialysis, and vial bag methods. Cytotoxicity assessment of HA and zinc-oxide gels was performed in human periodontal ligament fibroblasts (HPdLF) and human gingival fibroblasts (hGFs). An inverted phase-contrast microscope was used to assess the morphological changes. At 24 and 48 hr, HPdLF cells showed the highest viability in 0.1% low molecular weight-HA (LMW-HA) with a median value of 131.9, and hGFs showed the highest viability in 5% LMW-HA with a median of 129.56. The highest viability of HPdLF cells was observed in 5% high molecular weight-HA (HMW-HA), with a median value of 127.11. hGFs showed the highest viability in 1% HMW-HA with a median value of 97.99. Within the limitations of the present study, we concluded that LMW-HA is more efficient than HMW-HA. Both HPdLF and hGF cells showed complete cell morbidity with zinc-oxide hydrogels. Therefore, zinc oxide-based gels in concentrations as low as 9% could be toxic intraorally to soft tissues that harbor gingival and periodontal ligament fibroblasts. [ABSTRACT FROM AUTHOR]

Context: The proliferation and differentiation of human periodontal ligament stem cells (hPDLSC) into other cell types are also mediated by mechanical stresses; they might offer therapeutic benefits in tissue regeneration and angiogenesis. Objectives: The study was planned to assess the proliferation, clonogenic potential, and osteogenic differentiation of human periodontal ligament stem cells (PDLSC) following the application of light and heavy orthodontic forces. Materials and Methods: A couple forces of 50 gm (light force) were applied on the 1st premolar on the one side and 250 gm (heavy force) on the contralateral side in the upper arch of patients requiring orthodontic treatment with extraction of all 1st premolars. After 30 days, periodontal tissues were scrapped from extracted teeth for the establishment of PDLSC in vitro. PDLC from the lower premolar teeth where no orthodontic force was applied acted as the control group. Morphology, viability, proliferating rate and population doubling time, clonogenicity, and alkaline phosphatase activity were analysed. Result: The osteogenic potential was confirmed by Alizarin red staining and the expression of the osteogenic markers by qRT-PCR. The morphology, growth kinetics, potency, and osteogenic lineage characteristics inferred the application of high force reduced the proliferative ability and osteogenesis of PDLSC, though the difference was not significant. Conclusion: The established PDLSCs demonstrated their MSC-like properties based on morphology, growth kinetics, colony forming ability, and AP activity. The culture-expanded PDLSCs showed their differentiation potential into osteocytes. The application of high force reduced the proliferative ability and osteogenesis of PDLSCs, variations were not significant. [ABSTRACT FROM AUTHOR]

Background: The goal is to evaluate the microbial sterility of mesenchymal progenitor cells (MPCs)-derived from osteoarthritis (OA) and rheumatoid arthritis (RA) articular cartilages. Methods: Contaminants, including bacteria and fungi in MPC cultures were initially evaluated by inoculation culture methods and then affirmed through the amplification of 16S ribosomal DNA (rDNA) and internally transcribed spacer (ITS) regions, respectively, using polymerase chain reaction (PCR). Further, the mollicutes, if any, were identified by genus-specific 16S rDNA, and the positive samples were reamplified using species-specific primers. Results: No bacteria or fungi were found to be compromising the sterility of MPCs (n = 20) assessed by both traditional culture methods and PCR. However, two in early passages and three in later passages of MPCs had the presence of mollicutes. Further rescreening for species of mollicutes indicated the presence of Mycoplasma hyorhinis, M. salivarium, and M. arginine. Conclusions: The PCR methods employed in this study could be beneficial as a rapid sterility testing of cell lines. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) shed by human-induced pluripotent stem cell (hiPSC)-derived neural stem cells (hNSC-EVs) have shown potent antiinflammatory properties in a mouse macrophage assay and a mouse model of acute neuroinflammation. They can also quickly permeate the entire brain after intranasal administration, making them attractive as an autologous or allogeneic off-the-shelf product for treating neurodegenerative diseases. However, their ability to modulate activated human microglia and specific proteins and miRNAs mediating antiinflammatory effects of hNSC-EVs are unknown. We investigated the proficiency of hNSC-EVs to modulate activated human microglia and probed the role of the protein pentraxin 3 (PTX3) and the miRNA miR-21-5p within hNSC-EVs in mediating the antiinflammatory effects. Mature microglia generated from hiPSCs (iMicroglia) expressed multiple microglia-specific markers. They responded to lipopolysaccharide (LPS) or interferon-gamma challenge by upregulating tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) mRNA expression and protein release. iMicroglia also exhibited proficiency to phagocytose amyloid-beta (Aβ). The addition of hNSC-EVs decreased TNF-α and IL-1β mRNA expression and the release of TNF-α and IL-1β by LPS-stimulated iMicroglia (proinflammatory human Microglia). However, the antiinflammatory activity of hNSC-EVs on LPS-stimulated microglia was considerably diminished when the PTX3 or miR-21-5p concentration was reduced in EVs. The results demonstrate that hNSC-EVs are proficient for modulating the proinflammatory human microglia into non-inflammatory phenotypes, implying their utility to treat neuroinflammation in neurodegenerative diseases. Furthermore, the role of PTX3 and miR-21-5p in the antiinflammatory activity of hNSC-EVs provides a new avenue for improving the antiinflammatory effects of hNSC-EVs through PTX3 and/or miR-21-5p overexpression. [ABSTRACT FROM AUTHOR]

Objectives: Dental tissues possess multipotent stem cells with varying biological properties. The present study was aimed to establish a primary culture of human gingiva-derived mesenchymal stem cells (GMSCs) and periodontal ligamentderived stem cells (PDLSCs) from periodontally healthy subjects and compare their biological characteristics. Materials and Methods: Gingival and periodontal ligament (PDL) tissues were collected from extracted premolar teeth of five healthy subjects and primary cultures were established. Basic biological characteristics, such as cell morphology, viability, proliferation capacity, and colony-forming units, and in vitro osteogenic and adipogenic differentiation potential were performed at passage 3 of GMSCs and PDLSCs. This was followed by immuno-phenotyping and flow cytometric analysis for identification of positive mesenchymal stem cell (MSC) markers, such as CD73, CD90, and CD105, and negative markers CD45 and CD34. Statistical Analysis Used: One-way analysis of variance (ANOVA). Results: Primary cultures of GMSCs and PDLSCs were successfully established. Cells exhibited a fibroblast-like morphology with a homogeneous population at passage 3. Cells derived from both tissues were highly viable (>95%), proliferative, and capable of forming colonies. Both cells did not exhibit any noticeable differences in cellular properties. Immunofluorescence and flow cytometric analyses showed positivity for MSC markers, CD73, CD90, and CD105, and negativity for CD34 and CD45. Furthermore, GMSCs and PDLSCs were capable of differentiating in vitro into osteocytes as evidenced by Alizarin red-S staining, and adipocytes as demonstrated by oil red O staining. Conclusions: The results of the present study indicate that both GMSCs and PDLSCs have similar cellular characteristics and mesenchymal differentiation potential. Therefore, they may serve as an equally potent source of stem cells for use in cell-based periodontal therapies. [ABSTRACT FROM AUTHOR]

Objective: Gingiva-derived mesenchymal stem cells (GMSCs) have been identified and characterized from healthy tissues. However, reports on the influence of chronic inflammation on their stemness characteristics are sparse. The present study evaluated the potency and differentiation ability of GMSCs from periodontally healthy GMSC (H-GMSC) and inflamed GMSC (I-GMSC) tissues. Materials and Methods: Established H-GMSCs and I-GMSCs were evaluated on their potency characteristics, such as morphology, viability, proliferation rate, population doubling time, colony-forming ability, expression of stemness markers, and mesenchymal differentiation potential. Results: H-GMSCs and I-GMSCs exhibited fibroblast-like morphology and showed >95% viability with high proliferation potential and shorter doubling time. H-GMSCs showed fewer and smaller colonies, whereas I-GMSCs exhibited multiple and larger colonies. The evaluation of stemness markers revealed that both H-GMSCs and I-GMSCs were weakly positive for stage-specific embryonic antigen-4, Stro1, and CD105 (Endoglin), strongly positive for CD73 and CD90, and negative for the hematopoietic cell markers, CD34 and CD45. H-GMSCs showed a slightly higher osteogenic potential when compared to I-GMSCs, while I-GMSCs had a higher adipogenic potential than H-GMSCs. Conclusion: The findings showed that the inflammatory environment might have a stimulatory effect on the growth kinetics and ability of colony formation in GMSCs. However, varied osteogenic and adipogenic differentiation was observed between H-GMSCs and I-GMSCs. [ABSTRACT FROM AUTHOR]

Background: Tumor cells that have the ability to express vascular endothelial growth factor (VEGF) are more competent to growth and metastasize by the adequate amount of blood and oxygen supply by the blood vessels to the growing mass of cells. Hypoxic tumors are known for its aggressiveness and resistance to the treatment. Targeting VEGF and hypoxia‑inducible factor‑1 alpha (HIF‑1α) is an attractive strategy to interrupt the multiple pathways crucial for tumor growth. In the present study, two thiazole acetamide derivative’s anticancer property, anti VEGF and HIF‑1α inhibitory property were investigated. Methodology: Two thiazole acetamide compounds were synthesized, TA1 and TA2 and its anticancer property was studied in Erlich’s ascites cancer cells. To evaluate the anticancer property the assays such as 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide assay, DNA diffusion assay for apoptosis, and lactate dehydrogenase leakage assay were carried out. The cell culture media was used to assess the secreted VEGF level. Molecular docking studies were performed to analyze the binding efficiency of the study compounds to the kinase insert domain‑containing receptor (KDR) and fms‑like tyrosine kinase (FLT)‑binding domains of VEGF protein. HIF‑1α inhibitory study was performed by flow cytometry analysis using HUVEC cell line. Results: The study compounds inhibited HIF‑1α and VEGF secretion, these data shown positive prop up for the anticancer property of the derivatives. The docking studies showed moderate binding of study compounds to KDR and FLT‑binding domains of VEGF protein. Conclusion: These results conclude the anticancer and anti‑angiogenic property of the synthesized thiazole‑acetamide derivatives. [ABSTRACT FROM AUTHOR]

Background: Tumor cells that have the ability to express vascular endothelial growth factor (VEGF) are more competent to growth and metastasize by the adequate amount of blood and oxygen supply by the blood vessels to the growing mass of cells. Hypoxic tumors are known for its aggressiveness and resistance to the treatment. Targeting VEGF and hypoxia-inducible factor-1 alpha (HIF-1α) is an attractive strategy to interrupt the multiple pathways crucial for tumor growth. In the present study, two thiazole acetamide derivative's anticancer property, anti VEGF and HIF-1α inhibitory property were investigated.Methodology: Two thiazole acetamide compounds were synthesized, TA1 and TA2 and its anticancer property was studied in Erlich's ascites cancer cells. To evaluate the anticancer property the assays such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, DNA diffusion assay for apoptosis, and lactate dehydrogenase leakage assay were carried out. The cell culture media was used to assess the secreted VEGF level. Molecular docking studies were performed to analyze the binding efficiency of the study compounds to the kinase insert domain-containing receptor (KDR) and fms-like tyrosine kinase (FLT)-binding domains of VEGF protein. HIF-1α inhibitory study was performed by flow cytometry analysis using HUVEC cell line.Results: The study compounds inhibited HIF-1α and VEGF secretion, these data shown positive prop up for the anticancer property of the derivatives. The docking studies showed moderate binding of study compounds to KDR and FLT-binding domains of VEGF protein.Conclusion: These results conclude the anticancer and anti-angiogenic property of the synthesized thiazole-acetamide derivatives. [ABSTRACT FROM AUTHOR]

Context: Dental tissue remains are the toughest, and chemically, the most stable tissue in the body. Its high resilience in the events of fire and bacterial decomposition makes them vital for DNA analysis by PCR method.Aims: Determination of sex of children through molecular analysis of pulp tissue of exfoliated deciduous teeth stored in different media and analyzed after a different time period.Settings and Design: Sixty samples of deciduous teeth were divided into three groups. Group IA and Group IIA were stored in natural soil and wet clay for 1 month, respectively. Group IB and Group IIB were stored in natural soil and wet clay for 6 months, respectively. Group III was analyzed immediately after extraction.Methods and Material: Sex determination was carried out in five steps: Pulp tissue removal, DNA isolation, DNA quantification, PCR amplification, Sex determination. X and Y specific chromosomes from each sample were amplified and compared.Statistical Analysis Used: Kruskal-Wallis test, Dunn's test, and Wilcoxon signed rank test.Results: Group III revealed the highest amount of DNA quantified. Amount of DNA quantified after 6 months of storage in natural soil and wet clay decreased in both the groups with the samples stored in wet clay showing a maximum decrease. Results of the PCR analysis also showed 100% accuracy rate in the samples of Group III.Conclusions: Sex determination from pulp tissue depends a lot on the quality and quantity of DNA extracted. Sex could be effectively determined among the samples evaluated immediately after extraction. This ability decreases as the storage condition changes and the time period increases. Samples stored in wet clay were found to show the least sex identification ability than dry soil. [ABSTRACT FROM AUTHOR]

Background: Accurate determination of gender from the skeletal remains has a significant role in the identification process. In conditions of extreme fragmentation, information from DNA plays a vital role in establishing the gender of the person and further contributes to personal identification. Method: Sixty sound and non-carious extracted deciduous teeth were grouped into three of 20 each. Group 1 was analyzed immediately after extraction. Group 2 and Group 3 were stored at room temperature for three months and Fifteen months respectively before subjecting them to PCR analysis. The X and Y chromosomes from each sample were amplified and compared with the actual gender of the person. Shapiro-Wilk test the independent sample t-test, paired t-test and the chi-square test were used to analyze the data obtained. Result: The mean DNA volume (mg/ml) obtained immediately after extraction was significantly more than that from the teeth stored at room temperature for 15 months. The PCR analysis did not show any significant difference between group 1 and group 3 (p=0.072). Statistically significant difference was observed, when the results of group 1 were compared with that of group 3. Conclusion: Gender could be conclusively determined from the samples analyzed immediately after extraction. The accuracy of gender determination decreased as the period of storage increased. [ABSTRACT FROM AUTHOR]

Introduction: Diallyl disulphide is an organo-sulphur compound which is present in garlic and responsible for the characteristic odor of garlic. It is known for its anticancer and invitro membrane stabilizing properties. Aim: The main aim was to evaluate the haematopoietic, antioxidant and membrane stabilizing property of diallyl disulfide in irradiated mice. Materials and Methods: Mice were grouped into 6 groups as control, drug control, radiation control and drug pre-treatment groups (i.e. drug administration + radiation group) The mice were fed orally for 15 consecutive days and on the 15th day, one hour after drug administration, the mice were irradiated with 6Gy electron beam radiation. The changes in blood cell count, total antioxidant levels, malondialdehyde and reduced glutathione levels were determined. The immunomodulatory response of DADS to the radiological effects was determined by the estimation of IL-6 levels. Results: A significant improvement in pre-drug treatment group when compared to control groups in the haemoglobin, red blood cell count, white blood cell count, haematocrit and platelet counts was observed. There is an increased level of interleukin-6 in the drug treated groups compared to the radiation control. An increase in the malondialdehyde levels and decrease in the glutathione levels in the irradiated group indicate increased lipid peroxidation and oxidative stress, whereas, there is a significant reduction in the malondialdehyde levels and increased glutathione levels in the drug pre-treatment groups showing membrane stabilization. Conclusion: Thus DADS proves to be an effective haematopoietic and antioxidative agent to counter radiation induced haematopoietic suppression and oxidative stress. [ABSTRACT FROM AUTHOR]

The batch bioreduction of Cr(VI) by the cells of newly isolated chromium-resistant Acinetobacter sp. bacteria, immobilized on glass beads and Ca-alginate beads, was investigated. The rate of reduction and percentage reduction of Cr(VI) decrease with the increase in initial Cr(VI) concentration, indicating the inhibitory effect of Cr(VI). Efficiency of bioreduction can be improved by increasing the bioparticle loading or the initial biomass loading. Glass bioparticles have shown better performance as compared to Ca-alginate bioparticles in terms of batch Cr(VI) reduction achieved and the rate of reduction. Glass beads may be considered as better cell carrier particles for immobilization as compared to Ca-alginate beads. Around 90% reduction of 80 ppm Cr(VI) could be achieved after 24 h with initial biomass loading of 14.6 mg on glass beads. Artificial neural network-based models are developed for prediction of batch Cr(VI) bioreduction using the cells immobilized on glass and Ca-alginate beads. [ABSTRACT FROM AUTHOR]

Background: Infrapatellar fat pad-derived mesenchymal stem cells (IFP-MSCs) might provide a better tool for autologous cell therapy to irradiated patients. However, the changes in cellular and biological mechanisms of IFP-MSCs following their exposure to ionizing radiation remain to be elucidated. Objective: To investigate the sensitivity of IFP-MSCs to irradiation based on the selected cellular and basic biological characteristics. Methodology: In vitro established IFP-MSCs were irradiated with X-ray doses of 0, 0.5, 2 and 5 Gy. The characterization of the cells was carried out by analysing morphology, viability, proliferation rate, population doubling time (PDT), colony-forming ability, cell cycle status, senescence and osteogenic differentiation. Results: Irradiated IFP-MSCs retained their fibroblast-like morphology with higher viability at lower doses of 0.5 and 2 Gy exposure. However, 5 Gy irradiated cells showed granulation and slightly altered morphological features. The proliferation rate decreased gradually in 2 and 5 Gy exposed groups after day 9 and correspondingly PDT also increased when compared to control IFP-MSCs. Further, all cells exhibited their ability to form colonies with no visible variations after staining except in 5 Gy group. After radiation exposure, IFP-MSCs did not show any changes in cell cycle status, senescent activity and retained osteogenic differentiation potential by exhibiting their ability to secrete mineralised calcium nodules. Conclusion: These findings provide an understanding of radiation-induced cellular and biological responses in IFP-MSCs, and further studies on molecular mechanisms may lead to the development of better strategies for radiotherapy by autologous stem cell transplantation. [ABSTRACT FROM AUTHOR]

Background: Cell therapy using gingiva derived mesenchymal stem cells (GMSCs) is of high interest because of their intrinsic immunomodulatory and regenerative properties. However, there is presently sparse literature on the influence of irradiation on the cellular and inflammatory markers secretion GMSCs. Objective: The aim was to evaluate the cellular and secretion levels of selected inflammatory cytokines in GMSCs following irradiation. Methodology: Primary culture of GMSCs was established and irradiated with single doses of 0, 0.5, 2 and 5 Gy. Cellular morphology, viability, proliferation rate, population doubling time (PDT), colony-forming ability, and the levels of inflammatory cytokines, such as interleukin-2 (IL-2) and IL-6s after exposure to X-ray were analysed. The selected cytokines are known to be important in initiation and maintenance of inflammatory processes. Results: Cellular morphology, viability, proliferation rate and PDT were not markedly altered by ionising radiation at 0.5 and 2 Gy exposure. However, a loss of viability, proliferative capacity and colony formation was observed after irradiation at 5 Gy. Notably, irradiated GMSCs showed moderate to higher levels of IL-2 and IL-6 secretion compared to control group. Conclusion: The data suggested that ionising radiation at increasing doses induced cellular changes in GMSCs along with enhanced secretion of inflammatory cytokines. Further evidence is required for supporting the application of GMSCs in radiation therapies. [ABSTRACT FROM AUTHOR]

Background: Skin stem cells might be the major target to assess the ionising radiation effects. Recent evidences suggest that it may have significant effects on cellular functions. Because of their regenerative potential, dermal stem cells (DSCs) have been a subject of intense research, and they may provide an efficient means for treating radiation-induced tissue damage. Objective: The present study evaluated the effect of low dose irradiation on DSCs in terms of proliferation, potency and DNA fragmentation status. Methodology: Human DSCs were exposed to single doses of X-ray radiation 0, 0.5 and 2 Gy and assessed cell morphology, viability, proliferation, cell cycle status, senescence activity as well as the DNA fragmentation status. Results: DSCs showed a normal fibroblastic morphology, maintained a regular size, and were able to increase in number in 0.5 Gy group comparing to that of unirradiated DSCs. But irradiated DSCs at 2 Gy showed noticeable changes in morphology, viability and a decrease in proliferation gradually after day 6 of culture. The percentage of G0/G1 cells in DSCs in control was higher than the irradiated groups. However, senescence associated betagalactosidase assay revealed no presence of any senescent cells following 48 hrs post-irradiation. DNA fragmentation assay also showed no differences in the fragmented and intact DNA fractions between the control and irradiated DSCs. Conclusion: The findings showed that DSCs were resistant to low levels of ionising radiation with normal cellular characteristics and DNA repair capacity. [ABSTRACT FROM AUTHOR]

Recent evidences propose the role of a highly tumorigenic subpopulation of undifferentiated, self-renewing cancer stem cells in causing resistance to conventional anti-cancer therapy, recurrence, metastasis and heterogeneous tumor formation. Oral squamous cell carcinoma (OSCC) is one of the most common cancer types in India linked commonly with alcohol and tobacco use. Therefore, the isolation and in vitro characterization of cancer stem-like cells from OSCC tissues is a critical step to advance the understanding of the chemoresistance processes and for designing therapeutic strategies. The objective of this study was to establish and characterize cancer stem-like cells in vitro from OSCC. The primary cultures of cancer stem-like cell lines were established from the tissue biopsies of patients with clinical and histopathological evidence of OSCC. The viability of cells was more than 95% with marked proliferative activity and lesser doubling time. After being cultured for two weeks, cancer stem-like cells gradually aggregated and formed sphere-like bodies. Flow cytometry analysis of cancer stem-like cells showed a positive expression of specific markers, such as CD24, CD29, CD44, CD133 and ALDH1. In conclusion, the establishment of OSCC derived cancer stem-like cells could serve as an excellent in-vitro model for better understanding of the cause for recurrence and metastasis in oral epithelial malignancies from Indian perspective, where alcohol consumption and tobacco chewing are major risk habits [ABSTRACT FROM AUTHOR]