Alok K. Singh

Petrological and Geochemical Investigations of Rajpardi Lignite Deposit, Gujarat, India

The present paper entails the petrographic and chemical characteristics of the lignite samples drawn from the Rajpardi lignite deposit of Bharuch district, Gujarat. This lignite contains a high concentration of huminite which is dominated by telohuminite, followed by detrohuminite. Liptinite and inertinite macerals are very low in concentration. The dominant microlithotype is humite. Its elevated volatile matter and high hydrogen content depicts its perhydrous nature. The study reveals that this lignite originated in a limno-telmatic to telmatic condition. The paleomire is further characterized as a wet moor having moderate to high flooding with good tissue preservation and increasing bacterial activity.

Petrographic and geochemical characterization of coals from Tiru valley, Nagaland, NE India

In Tiru valley region of Mon district coals occur in Barail Formation and are of Oligocene age. This study is the first investigation on the petrographic and geochemical characterization of these coals. These thinly bedded seams (<2 m) need systematic exploration for proper evaluation of the resource. The coals are bright to moderately bright in appearance and at places look moderately dull. The study reveals that Tiru valley coals are sub-bituminous to bituminous-D in rank. The chemical study reveals that these coals are perhydrous in nature with moderately high volatile matter content. The sulphur content was probably increased with pyrite inclusion as the most abundant mineral. Vitrinite is the most dominant maceral group constituting nearly 98% of all the macerals while liptinite and inertinite occur in very low concentration. Facies-critical models used to decipher the paleodepositional environment suggest that these coals evolved under wet moor with moderately high flooding in the paleomire which allowed the sulphate reducing bacteria to thrive.

p53: its alteration and gallbladder cancer.

Gallbladder cancer (GBC) is the most common malignancy of the biliary tract. Despite the recent advancements in the understanding of cancer biology the disease still remains a therapeutic challenge with poor survival, and with early surgical resection as the only powerful treatment. Understanding the molecular events in gallbladder carcinogenesis may provide a novel targeted therapeutic approach. Of these, alterations in the tumour suppressor gene, p53, are commonly observed in most human cancers. However, its impact on the pathogenesis of GBC remains obscure. This study attempts to outline the p53 structure, function and its alterations, with special attention to GBC.

Genetic diversity studies and identification of SSR markers associated with Fusarium wilt (Fusarium udum) resistance in cultivated pigeonpea (Cajanus cajan).

Genetic diversity and identification of simple sequence repeat markers correlated with Fusarium wilt resistance was performed in a set of 36 elite cultivated pigeonpea genotypes differing in levels of resistance to Fusarium wilt. Twenty-four polymorphic sequence repeat markers were screened across these genotypes, and amplified a total of 59 alleles with an average high polymorphic information content value of 0.52. Cluster analysis, done by UPGMA and PCA, grouped the 36 pigeonpea genotypes into two main clusters according to their Fusarium wilt reaction. Based on the Kruskal–Wallis ANOVA and simple regression analysis, six simple sequence repeat markers were found to be significantly associated with Fusarium wilt resistance. The phenotypic variation explained by these markers ranged from 23.7 to 56.4%. The present study helps in finding out feasibility of prescreened SSR markers to be used in genetic diversity analysis and their potential association with disease resistance.

Petrological investigations of oligocene coals from foreland basin of northeast India

The results of the petrological investigations carried out on coal samples from the Oligocene deposits of Northeastern India (Assam, Arunachal Pradesh and Nagaland) have been discussed. These deposits occur in the Tikak Parbat Formation (Barail Group) and were probably deposited in the foreland basin. Petrographically, these coals are enriched in vitrinite macerals (65.8–96.6 vol %, mean 87.2 vol %) with variable concentrations of liptinite macerals (2.7–35.4 vol %, mean 11.9 vol %). They contain low concentration of inertinite (nil-3.3 vol %, mean 0.9 vol %) macerals. The microlithotype is dominated by vitrite (61.5–100 vol %, mean 90.8 vol %). An elevated volatile matter (44.15 – 60.20 wt %, mean 52.90 wt %, d.a.f. basis) and reflectance values (VRr 0.39–0.61%) put their rank as sub-bituminous type ‘C’ to high volatile bituminous type ‘C’. The GI and TPI values favour telmatic conditions of origin with high tree density and prolonged wet conditions. This is in agreement with the paleoenvironment interpreted from the vitrinite and liptinite-rich microlithotypes, which suggested a forest and reed facies. However, the presence of inertinite in some coal seams indicates tectonic upheavals / regression of the sea resulting to periodic and short span dryness of the basin.

Human mitochondrial genome flaws and risk of cancer.

Abstract Mitochondria perform significant roles in cellular energy metabolism. Among others, these functions include free radicals generation, control of cell death, growth, development, integration of signals from mitochondria to nucleus and nucleus to mitochondria, and various metabolic pathways. The biological impact of a given mutation may vary, depending on the nature of the mutation and the proportion of mutant mtDNAs carried by the cell. Identification of mtDNA mutations in precancerous lesions supports their early contribution to cell transformation and cancer progression. Introduction of mtDNA mutations in transformed cells has been associated with increased ROS production and tumor growth. Studies reveal that increased and altered mtDNA plays a role in the development of cancer but further work is required to establish the functional significance of specific mitochondrial mutations in cancer and disease progression. This review briefly summarizes the recent progress in this field.

The Prediction of the Liquefaction Behavior of the East Kalimantan Coals of Indonesia: An Appraisal through Petrography of Selected Coal Samples

The present study is undertaken to investigate the coals of East Kalimantan for their oil proneness and their suitability for hydrogenation. These coals are Sub-bituminous/Low rank A and per-hydrous in nature. They also have elevated sulphur content. Petrographically, they have high huminite (90.7–98.1%) and poor concentration of liptinite and inertinite. The study reveals that the coalification is characterized by loss of hydrogen and oxygen in this region. The richness of hydrogen, in relation to carbon, is probably responsible for vitrinite suppression and makes these coals per-hydrous and oil prone. The role of petrofactor has also been evaluated to predict reactivity of these coals during hydrogenation. There is a good correlation between petrofactor and conversion. These coals do possess favorable characteristics for hydrogenation and have a high conversion (~95%) and oil yield (>65%).

Obesity augmented breast cancer risk: A potential risk factor for Indian women†

Obesity is caused by disturbances of energy balance, which is homeostasized by the physiological processes. The study aims to determine the possible impact of rising prevalence of obesity and its effect in the development of breast carcinoma (BC) in Indian population.

Epigenetic silencing of BRCA1 gene associated with demographic and pathologic factors in sporadic breast cancer: a study of an Indian population.

Breast cancer (BC) is a leading cause of cancer-related deaths among women worldwide, and this study further demonstrates that the women of Varanasi (north India) are not untouched by this fatal disease. During BC development, epigenetic activity plays a key role in silencing gene expression. Its widespread occurrence in the cancer genome could inactivate many cellular pathways including DNA repair, cell cycle control, apoptosis, cell adherence, and detoxification. In this study, our aim was to determine the penetrance of BRCA1 promoter methylation and its correlation with pathological and demographic factors in sporadic BC in an Indian population. Our analysis included 127 patients who were diagnosed with sporadic BC. Methylation-specific PCR for the BRCA1 promoter was used during the study and correlated with pathological and demographic factors. Methylation of the BRCA1 promoter was detected in 8.7% (11/127) of the tumors. Correlation of promoter methylation with demographic factors and clinicopathological markers revealed the following data: (i) BRCA1 methylation was more frequently observed in tumor samples taken from premenopausal or perimenopausal women (P=0.026), (ii) methylation of the BRCA1 promoter negatively correlated with estrogen receptor (P=0.040), progesterone receptor (P=0.013), and epidermal growth factor receptor-2 (P=0.002), (iii) the overall promoter methylation was higher in more advanced stages (P=0.036) of the disease. This study has immense implications for understanding epigenetic mechanisms in BC development. The result suggests that the epigenetic silencing of BRCA1 is uncommon and is associated with the triple-negative phenotype.

Utilization of the Permian Coal Deposits of West Bokaro, India: A Petrochemical Evaluation

In the present investigation an attempt has been made to study the petrographic and geochemical characteristics of coal deposits of West Bokaro coalfield of India. Coal samples were subjected to detailed petrographic and geochemical analyses. The results reveal that these coals are rich in vitrinite with significant concentration of inertinite and a meager amount of liptinite. The mineral matter is dominated by argillaceous matter (clay minerals, quartz, etc.) followed by carbonate (ankerite, siderite, calcite, etc.) and suplphides (mainly pyrite), which occurs in different forms, such as dispersed, cavity filling, fissure filling, as well as massive impregnation. The volatile matter (d.a.f. basis) and reflectance values (Rom) suggest these coals to be between high volatile bituminous type B to medium volatile bituminous in rank. These coals can be best used for blending to produce metallurgical coke. The petrochemical characteristics of these coals favor their use in gasification and hydrogenation.