Pawan K. Dubey

Pressure-dependent synthesis of high-quality few-layer graphene by plasma-enhanced arc discharge and their thermal stability

In this article, a simple and cost-effective method to produce high-quality few-layer graphene (FLG) sheets (~4 layers) have been achieved by the direct current arc discharge under argon atmosphere, using pure graphite rods as the electrodes. Ar was used as a buffer gas with pure graphite rods as anode and cathode electrodes. We explored the suitable conditions for producing FLG by changing the Ar gas pressure inside the arcing chamber. This method has several advantages over the previous methods to produce graphene for research applications. No toxic and hazardous intercalant was used for producing FLG in this process. The optimum Ar pressure was 500xa0Torr, for producing minimum number of FLG and this also shows the good thermal stability. The FLG product so obtained has been characterized by X-ray diffraction, scanning and electron microscopy, Raman and Fourier transform infrared spectroscopy. Thermal stabilities of FLG were determined by thermal gravimetric analysis.

Evaluation of persistence and distribution of intra-dermally administered PKH26 labelled goat bone marrow derived mesenchymal stem cells in cutaneous wound healing model

The current study was designed to study the persistence and distribution of caprine bone marrow derived mesenchymal stem cells (cBM-MSCs) when administered intra-dermally in experimentally induced cutaneous wounds in rabbits. MSC’s from goat bone marrow were isolated and their differentiation potential towards adipogenic and osteogenic lineages were assayed in vitro. The isolated cells were phenotypically analysed using flow cytometry for the expression of MSC specific matrix receptors (CD73, CD105 and Stro-1) and absence of hematopoietic lineage markers. Further, these in vitro expanded MSCs were stained with PKH26 lipophilic cell membrane red fluorescent dye and prepared for transplantation into cutaneous wounds created on rabbits. Five, 2xa0cm linear full thickness skin incisions were created on either side of dorsal midline of New Zealand white rabbits (nxa0=xa04). Four wounds in each animal were implanted intra-dermally with PKH26 labelled cBM-MSCs suspended in 500xa0µl of Phosphate Buffer Saline (PBS). Fifth wound was injected with PBS alone and treated as negative control. The skin samples were collected from respective wounds on 3, 7, 10 and 14xa0days after the wound creation, and cryosections of 6xa0µM were made from it. Fluorescent microscopy of these cryosections showed that the PKH26 labelled transplanted cells and their daughter cells demonstrated a diffuse pattern of distribution initially and were later concentrated towards the wound edges and finally appeared to be engrafted with the newly developed skin tissues. The labelled cells were found retained in the wound bed throughout the period of 14xa0days of experimental study with a gradual decline in their intensity of red fluorescence probably due to the dye dilution as a result of multiple cell division. The retention of transplanted MSCs within the wound bed even after the complete wound healing suggests that in addition to their paracrine actions as already been reported, they may have direct involvement in various stages of intricate wound healing process which needs to be explored further.

Gestational Diabetes Mellitus: Risk and its Challenges

Gestational Diabetes Mellitus (GDM) is defined as glucose intolerance that was not present or recognized prior to pregnancy. GDM is associated with adverse outcome for mother and fetus. The prevalence of GDM varies from 1-14% and depends on population studied and diagnostic criteria used. This mini review discusses about the various aspects of GDM like aetiology, epidemiology, pathophysiology, diagnosis and management.

Comparative study on characterization and wound healing potential of goat (Capra hircus) mesenchymal stem cells derived from fetal origin amniotic fluid and adult bone marrow

Caprine amniotic fluid (cAF) and bone marrow cells (cBM) were isolated, expanded and phenotypically characterized by mesenchymal stem cells (MSCs) specific cell surface markers. Both cell types were compared for multilineage differentiation potential by flow cytometry using specific antibodies against lineage specific markers. Furthermore, in vitro expanded cAF-MSCs showed higher expression of trophic factors viz. VEGF and TGF-β1 as compared to cBM-MSCs. Full-skin thickness excisional wounds created on either side of the dorsal midline (thoracolumbar) of New Zealand White rabbits were randomly assigned to subcutaneous injection of either fetal origin cAF-MSCs (n=4) or adult cBM-MSCs (n=4) or sterile PBS (control, n=4). The rate of wound closure was found faster (p<0.05) in cAF-MSCs treated wounds as compared with cBM-MSCs and PBS treated wounds especially on 21st day post-skin excision. Histomorphological examination of the healing tissue showed that wound healing was improved (p<0.05) by greater epithelialization, neovascularization and collagen development in cAF-MSCs as compared to cBM-MSCs and PBS treated wounds.

Assisted Reproductive Technologies in Infertility Treatment: Opportunities and Challenges

A tremendous rise in the fertility clinics providing ART services is seen worldwide with the birth of first IVF baby (Louise Joy Brown) in 1978. ART comprises various types of medical treatments designed to assist in achieving pregnancy. IVF and other ART-associated technologies of fertilization (ICSI, IUI, PZD, SUZI, MESA, and PESA) offer an opportunity to become parent even in severe cases of infertility. These technologies have allowed millions of individuals to fulfill their parenting wish. A positive attitude combined with an appropriate treatment can help most of the infertile couples experience the joy of parenthood. This chapter provides a thorough overview of the assisted reproductive technologies with opportunities for patients and challenges for clinical professionals or researchers.

Application of CRISPR/Cas9 Genome Editing in Genetic Disorders: A Systematic Review Up to Date

Genetic diseases in human are associated with congenital disorders and phenotypic traits. A single mutation in a gene can cause physical or mental problems, and sometimes both. Some diseases can be lethal, and there are still no cures for many of them. Socioeconomic burden of rare genetic diseases are increasing worldwide that have been tried to cure using various methods. However, they were not very successful till now. Genome editing technologies over the past few years is providing fast and effective tool to precisely manipulate the genome at specific locations. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) associated Cas9 (CRISPR/Cas9) system has been using from last few years in the field of biomedical research. CRISPR/Cas9 has advantages in terms of clinical applicability to treat genetic diseases like DMD, Hemophilia, β-Thalassemia and cystic fibrosis etc. and even in some cases this tool has already been successfully applied. Nevertheless, developed technologies for addition or deletion of genes have made notable progress in last few years and demonstrate some promising clinical results. However, several challenges still remain. Here, the latest applications of CRISPR-Cas9 technology in genetic disorders, current challenges and future directions are reviewed and discussed.