Nitrogen-doped carbon dots: a novel biosensing platform for selective norfloxacin detection and bioimaging.

Incomplete metabolism and non-biodegradable nature of norfloxacin (NORx) lead to its persistent residues in the environment and food, potentially fostering the emergence of antibiotic resistance and posing a significant threat to public health. Hence, we developed a norfloxacin sensor employing hydrothermally synthesized N-doped carbon dots (N-Ch-CQDs) from chitosan and PEI demonstrated high sensitivity and specificity towards the antibiotic detection. The quantum yield of excitation-dependent emission of N-Ch-CQDs was effectively tuned from 4.6 to 21.5% by varying the concentration of PEI (5-15%). With the enhanced fluorescence in the presence of norfloxacin, N-Ch-CQDs exhibited a linear detection range of 20-1400 nM with a limit of detection (LoD) of 9.3 nM. The high biocompatibility of N-Ch-CQDs was confirmed in the in vitro and in vivo model and showed the environment-friendly nature of the sensor. Detailed study elucidated the formation of strong hydrogen bonds between N-Ch-CQDs and NORx, leading to fluorescence enhancement. The developed sensor's capability to detect NORx was evaluated in water and milk samples. The recovery rate ranged from 98.5% to 103.5%, demonstrating the sensor's practical applicability. Further, the bioimaging potential of N-Ch-CQDs was demonstrated in both the in vitro (L929 cells) and in vivo model (C. elegans). The synergistic influence of the defecation pattern and functioning of intestinal barrier mitigates the translocation of N-Ch-CQDs into the reproductive organ of nematodes. This study revealed the bioimaging and fluorescent sensing ability of N-Ch-CQDs, which holds significant promise for extensive application in the biomedical field.

Non-genetic effects and repeatability estimates of semen production traits in Murrah buffalo bulls.

The objectives of this study were to determine the repeatability estimates and the effect of ejaculate, season, period, age, and bull on semen production traits in Murrah buffalo bulls maintained in an organized semen station. A data set comprising 54,268 ejaculates from 76 Murrah buffalo bulls collected across 12 years were analyzed. The analysis of variables included non-genetic factors as the fixed effects and bull as the random effect. The repeatability was estimated by the restricted maximum likelihood method (REML) using WOMBAT program. The overall least-squares means for semen volume, sperm concentration, total sperm/ejaculate, mass activity, individual motility, post-thaw motility, and frozen semen straws/ejaculate were 2.65 ml, 1222.04 million/ml, 3030.10 million, 2.64, 67.45%, 51.73%, and 128.80 doses. The repeatability estimates were 0.27, 0.25, 0.22, 0.28, 0.34, 0.27, and 0.23, respectively. The studied non-genetic factors influenced (P < 0.01) all seminal traits. Likewise, variation (P < 0.01) due to individual bull was also observed. The first ejaculate was superior in terms of ejaculate volume, sperm concentration, total sperm/ejaculate, and frozen semen straws than the second ejaculate. The south-west monsoon and summer seasons were the best seasons with better semen quality and frozen semen production. Compared to the remaining periods, during Period V (2014-2016), greater values for most seminal traits were found. Bulls above 8 years of age expressed higher semen production than the younger bulls below 4 years, whereas the best performance was observed in the age group of 12 years and above. The repeatability estimates were low to moderate ranging from 0.22 for total sperm/ejaculate to 0.34 for individual motility. A significant (P < 0.01) positive correlation was observed between the seminal traits except the negative correlation in semen volume and total sperm/ejaculate. It was concluded that all the non-genetic factors considered in this study exerted influence on studied seminal traits. Therefore, appropriate management practices can be applied to improve semen quality and quantity.

Effect of gamma-ray irradiated reduced graphene oxide (rGO) on environmental health: An in-vitro and in-vivo studies.

The unique properties of reduced graphene oxide (rGO) have drawn the attention of scientists worldwide since the last decade and it is explored for a wide range of applications. However, the rapid expansion of rGO use in various products will eventually lead to environenal exposure and rises a safety concern on the environment and humal health risk. Moreover, the utilization of toxic chemicals for the reduction of graphene oxide (GO) into rGO is not environmentally friendly, warranting the exploration of non-toxic approaches. In the present work, rGO was synthesized using a different dose of gamma-ray irradiation and characterized. The in-vitro and in-vivo analysis indicated that the gamma-irradiated rGO induced toxicity depending on its degree of reduction and dosage. In the L929 cells, rGO-30 KGy significantly induced cytotoxicity even at low concentration (1 mg L-1) by inducing reactive oxygen species (ROS), lactate dehydrogenase (LDH) enzyme production, nuclear fragmentation and apoptosis. The change in morphology of the cells like membrane blebbing and cell rounding was also observed via FESEM. In the in-vivo model Caenorhabditis elegans, rGO-30 KGy significantly affected the functioning of primary and secondary targeted organs and also negatively influenced the nuclear accumulation of transcription factors (DAF-16/FOXO and SKN-1/Nrf2), neuronal health, and antioxidant defense mechanism of the nematodes. The real-time PCR analysis showed significant up-regulation (ced-3, ced-4, cep-1, egl-1, and hus-1) and down-regulation (ced-9) of the gene involved in germ-line and DNA damage-induced apoptosis. The detailed toxicity mechanism of gamma irradiated rGO has been elucidated. This work highlights the toxicity of rGO prepared by gamma-ray radiation and paves way for understating the toxicity mechanism.

One-step preparation of N-doped grapheme quantum dots with high quantum yield for bioimaging and highly sensitive electrochemical detection of isoniazid.

Conventional techniques for synthesizing GQDs have a poor quantum yield (QY) that restricts their biological applications. Herein, we present a rapid, cost-effective and high quantum yield synthesis of nitrogen-doped graphene quantum dots (N-GQDs) through a scientific microwave reactor. The reaction parameters like microwave irradiation time, temperature, precursor concentration and pressure were optimized for achieving high quantum yield. The prepared N-GQDs exhibit bright blue fluorescence and excitation independent emission property with a quantum yield of 42.81%. In-vivo investigations on C. elegans revealed that the as-prepared N-GQDs are exceptionally biocompatible and maintain the normal physiological functioning of the primary and secondary targeted organs in nematodes. The synergetic effect of intestinal barrier and defecation behavior mitigates N-GQDs translocation into reproductive organs of nematode. In addition, the N-GQDs modified GCE was tested for electrochemical sensing characteristics towards the anti-tuberculosis drug isoniazid (INZ). The N-GQDs showed appreciable electrocatalytic performance towards INZ with high sensitivity (3.76 µA µM-1 cm-1). The differential pulse voltammetry (DPV) analysis of N-GQDs exhibit a lower detection limit of 10.91 nM for INZ. The N-GQDs modified sensor exhibits good reproducibility, excellent anti-interference ability and excellent analytical performance for INZ in real samples like human blood serum and urine samples.

Highly effective and stable MWCNT/WO3 nanocatalyst for ammonia gas sensing, photodegradation of ciprofloxacin and peroxidase mimic activity.

The present study discusses the ammonia (NH3) sensing characteristics, photocatalytic degradation of emerging pollutants, and peroxidase mimic activity of multifunctional multi-walled carbon nanotube-tungsten oxide nanocomposite (MWCNT/WO3) prepared by conventional solvothermal method. The prepared MWCNT/WO3 nanocomposites were characterized by various analytical techniques like XRD, Raman, XPS, N2 adsorption, FESEM with elemental analysis and diffuse reflection spectroscopy. The prepared 1% MWCNT/WO3 nanocomposite showed better gas sensing performance for the NH3 vapors at 10-100 ppm than the pristine WO3 and the response and recover time of about 13 and 15s towards 20 ppm of ammonia (NH3) was achieved. The photocatalytic activity of MWCNT/WO3 towards organic dyes such as Rhodamine-B (Rh.B) methylene blue (MB) and pharmaceutical compound ciprofloxacin (CIP) were studied and achieved above 90% degradation at 160 min for CIP and 60 min for MB and Rho-B respectively. The radicle scavenging activity for MWCNT/WO3 nanocomposite showed the predominant formation of hydroxyl (OH•) and superoxide radicle (•O2-). Further, the MWCNT/WO3 nanocomposite showed peroxidase mimic activity and exhibit the limit of detection (LOD) of about 321 nM. From the overall analysis, MWCNT/WO3 hybrid seems to have potential characteristics that can be explored for multiple functional applications.

Rapid one-pot synthesis of PAM-GO-Ag nanocomposite hydrogel by gamma-ray irradiation for remediation of environment pollutants and pathogen inactivation.

Designing a cost-effective, high potential and recyclable catalyst remains a challenge. In the present work, a monolithic PAM-GO-Ag hydrogel is prepared by a facile, eco-friendly method using gamma-ray irradiation. The formation of GO-Ag composite by gamma radiation is also investigated and it is authenticated by XRD, FTIR, Raman, XPS and TEM analysis. The PAM-GO-Ag hydrogel exhibits excellent catalytic activity to different catalysant like methylene blue, Rhodamine-B, and pharmaceutical compound ciprofloxacin. The high catalyst carrying capacity and rapid electron shuttling ability of GO plays a significant role in the high performance of PAM-GO-Ag hydrogel. The PAM-GO-Ag hydrogel also exhibits excellent antibacterial activity. The damaged cell membrane, protein leakage, and increased ROS level contribute to the antibacterial activity of PAM-GO-Ag. The monolithic structure of PAM-GO-Ag hydrogel makes it easy to handle, recover, and reuse for several runs without significant loss of catalytic and antibacterial activity. All these results showed the possible application of PAM-GO-Ag hydrogel as a promising catalyst for the reduction of different pollutants and antibacterial agents on a large scale with good reusability.

Engineering the surface of graphene oxide with bovine serum albumin for improved biocompatibility in Caenorhabditis elegans.

Graphene oxide (GO) has been extensively studied for its potential biomedical applications. However, its potential risk associated with the interactions of GO in a biological system hampers its biomedical applications. Therefore, there is an urgent need to enhance the biocompatibility of GO. In the present study, we decorated the surface of GO with bovine serum albumin (GO-BSA) to mitigate the in vivo toxic properties of GO. An in vivo model Caenorhabditis elegans has been used to study the potential protective effect of BSA decoration in mitigating GO induced toxicity. The BSA decoration on the surface of GO prevents the acute and prolonged toxicity induced by GO in primary and secondary organs by maintaining normal intestinal permeability, defecation behavior, development, and reproduction. Notably, GO-BSA treatment at 0.5-100 mg L-1 does not affect the intracellular redox status and lifespan of C. elegans. Reporter gene expression analysis revealed that exposure to GO-BSA (100 mg L-1) did not significantly influence the nuclear accumulation and expression patterns of DAF-16/FOXO and SKN-1/Nrf2 transcription factors and their downstream target genes sod-3, hsp-16.2, ctl-1,2,3, gcs-1, and gst-4 when compared to exposure to pristine GO. Also, quantitative real-time PCR results showed that GO-BSA did not alter the expression of genes involved in regulating DNA damage checkpoints (cep-1, hus-1 and egl-1) and core signaling pathways of apoptosis (ced-4, ced-3 and ced-9), in contrast to GO treatment. All these findings will have an impact on the future development of safer nanomaterial formulations of graphene and graphene-based materials for environmental and biomedical applications.

Genetic evaluation of growth in farmers' flocks of Madras Red sheep under long-term selection in a group breeding scheme.

The Network Project on Sheep Improvement (NWPSI)-Madras Red field unit is a group breeding scheme involving 198 farmers' flocks of Madras Red sheep in which selection for growth traits and rotation of rams have been practised for over two decades. Growth data collected from these flocks were used to evaluate the performance and understand the direct and expected responses to selection based on genetic parameters. The body weight at birth (BW), weaning weight (WW), 6-month weight (6W), 9-month weight (9W), 12-month weight (YW), pre-weaning average daily gain (ADG1, birth to 3 months), post-weaning ADG2 (3-6 months), ADG3 (6-9 months), ADG4 (9-12 months) and ADG5 (3-12 months) were 2.67, 10.05, 14.56, 18.36, 21.36, 80.13, 49.05, 43.00, 34.21 and 41.18 g, respectively. Univariate analyses were carried out using animal and sire models to estimate variance components. Heritability obtained from animal model for BW was 0.36 and the values for other body weight traits were almost unity. Heritability estimate for pre-weaning ADG1 was 0.31. Very high genetic variability was observed in spite of long-term selection and this sustenance of variability is one of the main advantages of a group breeding scheme, combining several flocks of smaller size. An increasing genetic and phenotypic trend was noticed for almost all the traits studied. The expected responses calculated based on genetic parameters also indicated scope for improvement.

Genetic evaluation of reproduction performance of Jersey × Red Sindhi crossbred cows.

AIM: The present investigation was undertaken to study the reproduction performance and effect of non-genetic factors on reproduction performance of Jersey crossbred cows. MATERIALS AND METHODS: Data on 355 Jersey crossbred cattle maintained at the Post-graduate Research Institute in Animal Sciences, Kattupakkam, Tamil Nadu, distributed over 30 years (1985 to 2014). The effect of various non-genetic factors including the period of birth, season of birth, period of calving, season of calving and parity were analyzed through least-squares analyses using univariate general linear model. The different (co)variance components for calculation of genetic parameters were estimated using restricted maximum likelihood method by fitting an animal model. RESULTS: The overall least-squares means (±standard error) of age at first service, age at first calving, weight at first calving, service period, calving interval, dry period, and number of services per conception were 848.06±9.72 days, 1204±12.20 days, 289.81±1.71 kg, 210.01±6.41 days, 489.12±6.45 days, 137.96±5.58 days, 2.50±0.07, respectively. Period of calving had either significant (p<0.05) or highly significant (p<0.01) effect on all reproduction traits studied except service period, calving interval, and dry period. Number of services per conception was affected by season of calving. Parity had significant influence (p<0.05) or highly significant (p<0.01) influence on all the traits studied except service period and dry period. Heritability estimates of age at first service, age at first calving, weight at first calving, service period, calving interval, dry period, and number of services per conception were 0.299, 0.220, 0.017, 0.142, 0.222, 0.177, and 0.042, respectively. The estimates of repeatability for service period, calving interval, dry period, and number of services per conception were 0.219, 0.234, 0.420, and 0.001, respectively. CONCLUSIONS: The reproduction performances of Jersey × Red Sindhi crossbreds were lower when compared to the earlier reports on Jersey crossbreds. Heritability and repeatability values were also low to moderate, indicating limited scope for improvement through selection.

Pleomorphic xanthoastrocytoma with anaplastic features: a case report.

Pleomorphic xanthoastrocytoma has been considered as an astrocytic tumor with relatively favorable prognosis. It corresponds to WHO Grade-II neoplasm. Recently, several patterns with relatively poor prognosis have been recorded and a new concept of "PXA with anaplastic features" has been proposed. The present case is about a 9-year-old girl who presented with symptoms of recurrent headache, seizures and poor academic performance. MRI revealed left fronto-parietal irregular enhancing mass lesion with callosal involvement and right mid-brain arteriovenous malformation. Clinical and radiological examination was suggestive of a high grade glial neoplasm/PNET. A diagnosis of high grade glial neoplasm was rendered on the squash smears submitted for frozen sections based on the presence of spindle cells, admixed with pleomorphic bizarre, giant cells with multilobated nuclei showing few atypical mitosis and abundant eosinophilic cytoplasm. Frontal craniotomy with debulking of the tumor was performed and permanent sections revealed a biphasic glial neoplasm with spindle cells arranged in fascicles admixed with bizarre multinucleated giant cells showing abundant vacuolated and lipidized cytoplasm, nuclear hyperchromasia with intranuclear inclusions. Eosinophilic granular bodies, mitosis of 7/10 HPF, micro vascular proliferation, necrosis and invasion into the underlying brain parenchyma were noted. With these histomorphological findings a diagnosis of pleomorphic xanthoastrocytoma with anaplastic features was rendered.

Genetic characterization of Barbari goats using microsatellite markers.

Genetic variation in Barbari goats, a highly prolific breed distributed widely in the northern part of India, known for better milk and meat quality, was studied as a part of genetic characterization and conservation. The genomic DNA from 50 unrelated Barbari goats were amplified via PCR with a panel of 21 microsatellite markers, and resolved through 6 per cent denaturing polyacrylamide gel electrophoresis followed by silver staining. The number of alleles ranged from 4 to 11, with allele sizes ranging from 88 to 220 bp. The distribution of allele frequencies was between 0.0104 and 0.5208. Polymorphism information content varied from 0.5563 to 0.8348. The population was not in Hardy-Weinberg equilibrium for all except two microsatellite loci (ILSTS044 and ILSTS060). The observed heterozygosity ranged from 0.8478 to 1.0000 while the expected heterozygosity ranged from 0.6208 to 0.8509. Based on the results of the present study, there is a good scope for exploiting the genetic variability in the Barbari goats for further improvement of performance.

Evaluation of fertility status of Murrah buffalo bulls in vitro using zona-free hamster eggs.

Cryopreserved semen samples from 10 Murrah buffalo bulls were used for sperm penetration bioassay using zona-free hamster oocytes. The samples were evaluated for sperm motility, viability and acrosome integrity. Actively motile spermatozoa recovered by the swim-up technique were capacitated using calcium ionophore A(2 3 1 8 7). Mature female golden hamsters were superovulated with 50 IU PMSG followed 56 h later by 75 IU hCG. Cumulus mass, recovered by puncture of oviducts at the infundibulum region, was treated with 0.1% hyaluronidase and 0.1% trypsin to obtain zona-free oocytes. After coincubation of zona-free oocytes with capacitated buffalo spermatozoa, scoring was done as fertilization percentage and fertilization index. The correlation coefficients with conception rate were statistically significant with fertilization percentage (r = 0.588, P < 0.05) and fertilization index (r = 0.660, P < 0.01). However, conventional parameters like viability, motility and acrosome integrity showed poor correlation with conception rate.