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Since its inception, DNA typing technology has been practiced as a robust tool in criminal investigations. Experts usually utilize STR profiles to identify and individualize the suspect. However, mtDNA and Y STR analyses are also considered in some sample-limiting conditions. Based on DNA profiles thus generated, forensic scientists often opine the results as Inclusion, exclusion, and inconclusive. Inclusion and exclusion were defined as concordant results; the inconclusive opinions create problems in conferring justice in a trial- since nothing concrete can be interpreted from the profile generated. The presence of inhibitor molecules in the sample is the primary factor behind these indefinite results. Recently, researchers have been emphasizing studying the sources of PCR inhibitors and their mechanism of inhibition. Furthermore, several mitigation strategies- to facilitate the DNA amplification reaction -have now found their place in the routine DNA typing assays with compromised biological samples. The present review paper attempts to provide a comprehensive review of PCR inhibitors, their source, mechanism of inhibition, and ways to mitigate their effect using PCR facilitators.

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Microfluidics is the technology or system wherein the behavior of fluids' is studied onto a miniaturized device composed of chambers and tunnels. In biological and biomedical sciences, microfluidic technology/system or device serves as an ultra-high-output approach capable of detecting and separating the biomolecules present even in trace quantities. Given the essential role of protein, the identification and quantification of proteins help understand the various living systems' biological function regulation. Microfluidics has enormous potential to enable biological investigation at the cellular and molecular level and maybe a fair substitution of the sophisticated instruments/equipment used for proteomics, genomics, and metabolomics analysis. The current advancement in microfluidic systems' development is achieving momentum and opening new avenues in developing innovative and hybrid methodologies/technologies. This chapter attempts to expound the micro/nanofluidic systems/devices for their wide-ranging application to detect and separate protein. It covers microfluidic chip electrophoresis, microchip gel electrophoresis, and nanofluidic systems as protein separation systems, while methods such as spectrophotometric, mass spectrometry, electrochemical detection, magneto-resistive sensors and dynamic light scattering (DLS) are discussed as proteins' detection system.

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BACKGROUND: Most of the forensic DNA laboratories have migrated to new generation STR kits of 6 dye chemistry with more than 20 autosomal STRs. The population-specific databases of such STR markers are lacking in many regions. AIM: To evaluate the effect of the inter-population database in 100 paternity trios with no inconsistencies at 23 STRs. SUBJECTS AND METHODS: 100 paternity trios were evaluated considering inter-population allelic frequency values for calculation of Combined Paternity Index (CPI) and Probability of Paternity (POP). RESULTS: No significant variation (p < 0.05) among the allele frequencies at the interpopulation level was observed. The number of obligate alleles and the likelihood of transferring obligate alleles from the putative father showed a positive correlation (p < 0.005) with Power of Discrimination (PD), Polymorphic Information Content (PIC), Power of Exclusion (PE), Paternity Index (PI), Observed and Expected Heterozygosity (Ho and He), and a statistically significant negative correlation (p < 0.005) with Matching Probability (Pm). The average Combined Paternity Index (CPI) and Probability of Paternity (POP) did not show any statistically significant difference (p < 0.05) at the interpopulation level. CONCLUSION: The allelic database showed no effect on the CPI and POP in 100 paternity trios. This suggests no urgent need for using population-specific databases for statistical evaluation of paternity trios without inconsistencies.

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The rapid advancement of nanotechnology enhances the production of different nanoparticles that meet the demand of various fields like biomedical sciences, industrial, material sciences and biotechnology, etc. This technological development increases the chances of nanoparticles exposure to human beings, which can threaten their health. It is well known that various cellular processes (transcription, translation, and replication during cell proliferation, cell cycle, cell differentiation) in which genetic materials (DNA and RNA) are involved play a vital role to maintain any structural and functional modification into it. When nanoparticles come into the vicinity of the cellular system, chances of uptake become high due to their small size. This cellular uptake of nanoparticles enhances its interaction with DNA, leading to structural and functional modification (DNA damage/repair, DNA methylation) into the DNA. These modifications exhibit adverse effects on the cellular system, consequently showing its inadvertent effect on human health. Therefore, in the present study, an attempt has been made to elucidate the genotoxic mechanism of nanoparticles in the context of structural and functional modifications of DNA.

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The new pedagogical approach of teaching and learning provides better deliverables by the teachers and better understanding and student engagement. In this order, a course was designed on Forensic Science for undergrad students from interdisciplinary background. Six pedagogies were used in this course with the aim to develop creativity, critical and logical thinking, practical learning, social accountability and research aptitude among the students. The main reasons for selecting these students were to avoid influencing the learning outcome due to their prior knowledge and observing the actual impact of the pedagogical learning. The suggested approach may be helpful in reducing the theoretical and practical gap in forensic science education. Besides, this teaching and learning approach may open a new avenue of forensic research and may result in a paradigm shift.

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Zinc oxide nanoparticles (ZnO NPs) with their wide range of consumer applications in day-to-day life received great attention to evaluate their effects in humans. This study has been attempted to elucidate the DNA damage response mechanism in a dermal model exposed to ZnO NPs through Ataxia Telangiectasia Mutated (ATM)-mediated ChK1-dependent G2/M arrest. Further, viability parameters and mechanism involved in the cell death with special reference to the consequences arising due to DNA damage were explored. Our study showed that ZnO NPs at concentrations 5 and 10 µg/ml induced significant cytotoxic effect in skin cell line. Moreover, the results confirmed generation of reactive oxygen species (ROS) induces the cell death by genotoxic insult, leading to mitochondrial membrane depolarisation and cell cycle arrest. Subsequently, ZnO NPs treatment created DNA damage as confirmed via Comet assay (increase in olive tail moment), micronucleus assay (increase in micronucleus formation), double-strand breaks (increase in ATM and Ataxia Telangiectasia and Rad3 related (ATR) expression), DNA fragmentation and cell cycle (G2/M arrest) studies. Finally, marker proteins analysis concluded the mechanistic approach by demonstrating the key marker expressions HMOX1 and HSP60 (for oxidative stress), cytochrome c, APAF1, BAX, Caspase 9, Caspase 3 and decrease in BCL2 (for activating apoptotic pathway), pATM, ATR and γH2AX (for double-strand breaks), DNA-PK (involved in DNA repair) and decrease in cell cycle regulators. In together, our data revealed the mechanism of ROS generation that triggers apoptosis and DNA damage in HaCaT cell lines exposed to ZnO NPs.

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Little is known of the effects of nanoparticles in human systems, let alone in diseased individuals and nanotechnology has preceded nanotoxicology. Therefore, the effects of titanium dioxide (TiO2) nanoparticles in peripheral blood lymphocytes from patients with respiratory diseases [lung cancer, chronic obstructive pulmonary disease (COPD) and asthma] were compared with those in healthy Individuals, to determine differences in sensitivity to nanochemical insult. The Comet assay was performed according to recommended guidelines. The micronucleus assay and ras oncoprotein detection were conducted according to published standard methods. The results showed statistically significant concentration-dependent genotoxic effects of TiO2 NPs in both respiratory patient and control groups in the Comet assay. The TiO2 NPs caused DNA damage in a concentration dependent manner in both groups (respiratory and healthy controls) with the exception of the lowest TiO2 concentration (10 µg/ml) which did not induce significant damage in healthy controls (n.s). When OTM data were used to compare the whole patient group and the control group, the patient group had more DNA damage (p > 0.001) with the exception of 10 µg/ml of TiO2 that caused less significant damage to patient lymphocytes (p < 0.05). Similarly, there was an increase in the pattern of cytogenetic damage measured in the MN assay without statistical significance except when compared to the negative control of healthy individuals. Furthermore, when modulation of ras p21 expression was investigated, regardless of TiO2 treatment, only lung cancer and COPD patients expressed measurable ras p21 levels. Results were achieved in the absence of cytotoxicity.

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Overproduction of free radicals contributes to oxidative stress and inflammation leading to various disease conditions. Cerium oxide nanoparticles (nanoceria) have been shown to scavenge free radicals and have the potential for being used as a therapeutic agent in disease conditions. Therefore, in the present study, human monocytic leukemia cells (THP-1) were used as a model to evaluate the uptake and free radical scavenging activity of nanoceria. Our data showed a significant (P<0.05) increase in the internalization of nanoceria in a concentration-dependent (10-100 µg/mL) manner in THP-1 cells. Although no cytotoxicity was observed at these concentrations, nanoceria significantly (P<0.05) reduced the amount of reactive oxygen species. This was evident by a significant (P<0.05) decrease in the 2,7-dichlorofluorescein diacetate fluorescence observed in flow cytometry and fluorescence microscopy. The present study shows that nanoceria have therapeutic potential in diseases such as cancer.

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Over the last decade, there has been growing interest in developing novel nanoparticles (NPs) for biomedical applications. A safe-by-design approach was used in this study to synthesize biocompatible iron oxide NPs. The size of the particles obtained was ~100 nm. Although these NPs were significantly (P<0.05) internalized in MCF-7 (human breast adenocarcinoma cell line) cells, no adverse effect was observed in the cells as assessed by cytotoxicity assays (neutral red uptake and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) and cell cycle analysis. Our data demonstrate the potential of iron oxide NPs as a biocompatible carrier for targeted drug delivery.

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Cellulose paper based multifunctional nanoplatform shows great promise towards molecular sensing and diagnostics application due to their sustainability, biocompatibility, affordability, environmental appeal and broad chemical modification capabilities. Herein, we have effectively synthesized plasmonic silver-cellulose nanocomposite (SCN) using complete green and in situ approach using the hydroxyl groups of cellulose paper acting as the reducing agent and stabilizing agent. The fabricated SCN were investigated and characterized by SEM, UV-Vis, DLS, PXRD and EDX. The important influencing parameters such as temperature and pH were optimized during the fabrication of SCN. Besides, this SCN functionalized with 3-aminopropyltriethoxysilane and has been exploited for monitoring of fluoride ion from water samples with distinguishing F- from a wide range of environmental prevalent ions. These remarkable properties of SCN have been used as rapid, portable test panel which could be simple, lightweight and disposable.

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Postmortem interval (PMI) estimation is a recurring problem in the field of forensic medicine. Conventional methods are effective but are insufficient to estimate accurate and precise time of death or PMI. In addition, degradation of biological samples is another major problem in forensic science which affects the investigation process and misleads the result. Some previous studies reported that DNA fragmentation has strong correlation with PMI. DNA fragmentation increased with prolonged PMI. Comet assay is a rapid sensitive, versatile, reliable and cost effective technique that is specifically used for qualitative and quantitative estimation of nuclear DNA fragmentation. Due to this attribute, comet assay can help to estimate accurate and precise time of death for some extent that is for early PMI estimation. In addition, two confounding factors are responsible for DNA fragmentation: (1) micro-organism; (2) environmental condition. Here, comet assay plays a dual role: (1) partially degraded samples get repaired using repair enzyme; (2) accurate time since deposition can be measured without using repair enzyme. Furthermore, this assay can also help to identify potential exposures of environmental-released chemicals/toxicants and its deleterious effects on human population. In this way, comet assay shows its versatile applications that could be useful for forensic investigation. Therefore, with the help of this review, an attempt was made to explore the versatility of comet assay technique for forensic applications and its future perspective.

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PURPOSE: We assessed changes in the position of the lens with aging in a general population. METHODS: The population-based Central India Eye and Medical Study included 4711 subjects. As part of an ophthalmic examination, anterior segment length (ASL) was measured sonographically and calculated as anterior chamber depth plus lens thickness. Subjects with nuclear cataract grades 5 or more (43.9% of the sample) were excluded. RESULTS: The study included 2468 subjects (1176 [47.6%] men) with a mean age of 41.2 ± 8.5 years (range, 30-78 years) and mean axial length of 22.68 ± 0.81 mm (range, 19.89-31.02 mm). In multivariate analysis, longer ASL was associated with older age (P = 0.04; correlation coefficient B, 0.002; 95% confidence interval [CI], 0.000, 0.005) after adjusting for male sex (P < 0.001), longer axial length (P < 0.001), higher degree of nuclear cataract (P = 0.001), and higher body mass index (P = 0.02). Greater lens thickness was associated with older age (P < 0.001; B, 0.009; 95% CI, 0.007, 0.0011) after adjusting for male sex (P < 0.001), shallower anterior chamber depth (P < 0.001), and higher degree of nuclear cataract (P < 0.001). Deeper anterior chamber depth was associated with younger age (P < 0.001; B, -0.007; 95% CI, -0.008, -0.005) after adjusting for male sex (P < 0.001), thinner lens thickness (P < 0.001), and longer axial length (P < 0.001). Combining both analyses revealed that for each year increase in age, lens thickness increased by 0.009 mm, anterior chamber depth decreased by 0.007 mm, the posterior lens pole moved backward by 0.002 mm, and the lens center moved forward by 0.0025 mm. CONCLUSIONS: Increasing age before the development of cataract is associated with a slight forward movement of the lens center, adding to the lens paradox.

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TiO2 nanoparticles (NPs) have the second highest global annual production (∼3000 tons) among the metal-containing NPs. These NPs are used as photocatalysts for bacterial disinfection, and in various other consumer products including sunscreen, food packaging, therapeutics, biosensors, surface cleaning agents, and others. Humans are exposed to these NPs during synthesis (laboratory), manufacture (industry), and use (consumer products, devices, medicines, etc.), as well as through environmental exposures (disposal). Hence, there is great concern regarding the health effects caused by exposure to NPs and, in particular, to TiO2 NPs. In the present study, the genotoxic potential of TiO2 NPs in A549 cells was examined, focusing on their potential to induce ROS, different types of DNA damage, and cell cycle arrest. We show that TiO2 NPs can induce DNA damage and a corresponding increase in micronucleus frequency, as evident from the comet and cytokinesis-block micronucleus assays. We demonstrate that DNA damage may be attributed to increased oxidative stress and ROS generation. Furthermore, genomic and proteomic analyses showed increased expression of ATM, P53, and CdC-2 and decreased expression of ATR, H2AX, and Cyclin B1 in A549 cells, suggesting induction of DNA double strand breaks. The occurrence of double strand breaks was correlated with cell cycle arrest in G2/M phase. Overall, the results indicate the potential for genotoxicity following exposure to these TiO2 NPs, suggesting that use should be carefully monitored.

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Quantum dots are a group of inorganic nanomaterials exhibiting exceptional optical and electronic properties which impart distinct advantages over traditional fluorescent organic dyes in terms of tunable broad excitation and narrow emission spectra, signal brightness, high quantum yield and photo-stability. Aqueous solubility and surface functionalization are the most common problems for QDs employed in biological research. This review addresses the recent research progress made to improve aqueous solubility, functionalization of biomolecules to QD surface and the poorly understood chemistry involved in the steps of bio-functionalization of such nanoparticles.

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BACKGROUND: The use of metal oxide nanoparticles (titanium dioxide) in consumer and industrial products improves their quality but also underscores the possible adverse effects to human and environmental health. MATERIALS & METHODS: Mice were exposed orally for 14 consecutive days and analyzed for alteration in different hepatic enzymes, histopathological changes, oxidative stress, DNA damage, tumor suppressor and proapoptotic protein expression in liver cells. RESULTS: We observed a significant alteration in the level of hepatic enzymes and liver histopathology at a dose of 100 mg/kg body weight. Significant oxidative DNA damage was observed in liver cells, which could be attributed to oxidative stress. In addition, the increased expression of p53, BAX, caspase-3 and -9 proteins and decreased expression of antiapoptotic protein Bcl-2, suggest activation of the intrinsic pathway of apoptosis. CONCLUSION: High accumulation of titanium dioxide nanoparticles in the liver tissue would cause DNA damage and apoptosis through the intrinsic pathway.

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The present experiment was designed to study the 2.45 GHz low-level microwave (MW) irradiation-induced stress response and its effect on implantation or pregnancy in female mice. Twelve-week-old mice were exposed to MW radiation (continuous wave for 2 h/day for 45 days, frequency 2.45 GHz, power density=0.033549 mW/cm(2), and specific absorption rate=0.023023 W/kg). At the end of a total of 45 days of exposure, mice were sacrificed, implantation sites were monitored, blood was processed to study stress parameters (hemoglobin, RBC and WBC count, and neutrophil/lymphocyte (N/L) ratio), the brain was processed for comet assay, and plasma was used for nitric oxide (NO), progesterone and estradiol estimation. Reactive oxygen species (ROS) and the activities of ROS-scavenging enzymes- superoxide dismutase, catalase, and glutathione peroxidase-were determined in the liver, kidney and ovary. We observed that implantation sites were affected significantly in MW-irradiated mice as compared to control. Further, in addition to a significant increase in ROS, hemoglobin (p<0.001), RBC and WBC counts (p<0.001), N/L ratio (p<0.01), DNA damage (p<0.001) in brain cells, and plasma estradiol concentration (p<0.05), a significant decrease was observed in NO level (p<0.05) and antioxidant enzyme activities of MW-exposed mice. Our findings led us to conclude that a low level of MW irradiation-induced oxidative stress not only suppresses implantation, but it may also lead to deformity of the embryo in case pregnancy continues. We also suggest that MW radiation-induced oxidative stress by increasing ROS production in the body may lead to DNA strand breakage in the brain cells and implantation failure/resorption or abnormal pregnancy in mice.

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Titanium dioxide nanoparticles (TiO(2) NPs), widely used in consumer products, paints, pharmaceutical preparations and so on, have been shown to induce cytotoxicity, genotoxicity and carcinogenic responses in vitro and in vivo. The present study revealed that TiO(2) NPs induce significant (p < 0.05) oxidative DNA damage by the Fpg-Comet assay even at 1 µg/ml concentration. A corresponding increase in the micronucleus frequency was also observed. This could be attributed to the reduced glutathione levels with concomitant increase in lipid peroxidation and reactive oxygen species generation. Furthermore, immunoblot analysis revealed an increased expression of p53, BAX, Cyto-c, Apaf-1, caspase-9 and caspase-3 and decreased the level of Bcl-2 thereby indicating that apoptosis induced by TiO(2) NPs occurs via the caspase-dependent pathway. This study systematically shows that TiO(2) NPs induce DNA damage and cause apoptosis in HepG2 cells even at very low concentrations. Hence the use of such nanoparticles should be carefully monitored.

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Titanium dioxide nanoparticles (TiO2 NPs) are the most commonly used metal oxide NPs in various industrial and commercial products. The present study has demonstrated a significant cellular uptake of TiO2 NPs in the human keratinocyte cells (HaCaT) using transmission electron microscopy and flow cytometry. The data exhibited a significant (p < 0.05) concentration dependent decrease in cell viability and glutathione with concomitant increase in lipid peroxidation and reactive oxygen species. The increased oxidative stress further leads to apoptosis after 48 h of exposure. Our study demonstrates oxidative stress mediated apoptosis in human keratinocyte cells exposed to TiO2 NPs.

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Metal oxide nanoparticles such as TiO2 (< 100 nm) are used in lotions and sunscreens. Toxicity studies so far have reported the use of TiO2 NPs with size > 100 nm as determined by dynamic light scattering (DLS) technique. We used non-reactive chemical agents such as propylene glycol (PG), glycerol (G), ethylene glycol (EG) to prevent aggregation and maintain NPs in monodispersed state closer to the reported TEM size. The lowest concentration of PG (0.1%) along with complete culture media (RPMI 1640) showed mean hydrodynamic diameter of TiO2 NPs as 33.71 nm measured by DLS. The present study demonstrates a method to prepare stable TiO2 NPs in culture media for toxicity assessment. This is a significant contribution as the biological properties of NPs vary considerably with decrease in size.

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Graphite nanomaterials such as thermally exfoliated graphite oxide (GO) are versatile in many applications. However, little is known about its effects on biological systems. In this study we characrerized the GO using dynamic light scattering (DLS) along with the toxicological aspects related to cytotoxicity and apoptosis in normal human lung cells (BEAS-2B). A significant concentration and time dependent decrease in cell viability was observed at different concentrations (10-100 microg/ml) by the MTT assay after 24 and 48 h of exposure and significant increase of early and late apoptotic cells was observed as compared to control cells. Our study demonstrates that GO induces cytotoxicity and apoptosis in human lung cells.

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