Publications by authors named "Majumdar C"

Background: The prevalence of cannabis as the most commonly used illicit substance in the United States and around the globe is well-documented. Studies have highlighted a noticeable uptrend in the potency of cannabis in the United states. This report examines the concentration of cannabinoids in illicit cannabis samples seized by the United States Drug Enforcement Administration (DEA) over the last 10 years (2013-2022).

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Base excision repair (BER) enzymes are genomic superheroes that stealthily and accurately identify and remove chemically modified DNA bases. DNA base modifications erode the informational content of DNA and underlie many disease phenotypes, most conspicuously, cancer. The "OG" of oxidative base damage, 8-oxo-7,8-dihydroguanine (OG), is particularly insidious due to its miscoding ability that leads to the formation of rare, pro-mutagenic OG:A mismatches.

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Background: Cannabis policies have changed drastically over the last few years with many states enacting medical cannabis laws, and some authorizing recreational use; all against federal laws. As a result, cannabis products are marketed in dispensaries in different forms, most abundantly as flowers intended for smoking and sometimes vaping. All samples used in this study were obtained directly from law enforcement.

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In recent years, cannabis has been proposed and promoted not only as a medicine for the treatment of a variety of illnesses, but also as an industrial crop for different purposes. Being an agricultural product, cannabis inflorescences may be contaminated by environmental pathogens at high concentrations, which might cause health problems if not controlled. Therefore, limits have to be placed on the levels of aerobic bacteria as well as yeast and mold.

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The () ribosome can incorporate a variety of non-l-α-amino acid monomers into polypeptide chains but with poor efficiency. Although these monomers span a diverse set of compounds, there exists no high-resolution structural information regarding their positioning within the catalytic center of the ribosome, the peptidyl transferase center (PTC). Thus, details regarding the mechanism of amide bond formation and the structural basis for differences and defects in incorporation efficiency remain unknown.

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Cannabis has a long history of being credited with centuries of healing powers for millennia. The cannabis plant is a rich source of cannabinoids and terpenes. Each cannabis chemovar exhibits a different flavor and aroma, which are determined by its terpene content.

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The oxidative base damage, 8-oxo-7,8-dihydroguanine (8-oxoG) is a highly mutagenic lesion because replicative DNA polymerases insert adenine (A) opposite 8-oxoG. In mammalian cells, the removal of A incorporated across from 8-oxoG is mediated by the glycosylase MUTYH during base excision repair (BER). After A excision, MUTYH binds avidly to the abasic site and is thus product inhibited.

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DNA glycosylases remove damaged or modified nucleobases by cleaving the N-glycosyl bond and the correct nucleotide is restored through subsequent base excision repair. In addition to excising threatening lesions, DNA glycosylases contribute to epigenetic regulation by mediating DNA demethylation and perform other important functions. However, the catalytic mechanism remains poorly defined for many glycosylases, including MBD4 (methyl-CpG binding domain IV), a member of the helix-hairpin-helix (HhH) superfamily.

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Article Synopsis
  • This review analyzes the concentration of seven major cannabinoids, including THC and CBD, in herbal cannabis products seized by the DEA over the past decade (2009-2019).
  • The analysis of 14,234 cannabis samples revealed a significant increase in mean Δ-THC concentration from 9.75% in 2009 to 13.88% in 2019, along with fluctuations in the THC:CBD ratio.
  • The results suggest a growing trend towards higher potency and higher CBD content in illicit cannabis products, reflecting shifts influenced by the legalization of marijuana in several states.
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The DNA glycosylase MutY prevents deleterious mutations resulting from guanine oxidation by recognition and removal of adenine (A) misincorporated opposite 8-oxo-7,8-dihydroguanine (OG). Correct identification of OG:A is crucial to prevent improper and detrimental MutY-mediatedadenine excision from G:A or T:A base pairs. Here we present a structure-activity relationship (SAR) study using analogues of A to probe the basis for OG:A specificity of MutY.

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The human DNA base excision repair enzyme MUTYH (MutY homolog DNA glycosylase) excises undamaged adenine that has been misincorporated opposite the oxidatively damaged 8-oxoG, preventing transversion mutations and serving as an important defense against the deleterious effects of this damage. Mutations in the gene predispose patients to MUTYH-associated polyposis and colorectal cancer, and MUTYH expression has been documented as a biomarker for pancreatic cancer. Measuring MUTYH activity is therefore critical for evaluating and diagnosing disease states as well as for testing this enzyme as a potential therapeutic target.

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Premise: How genetic variation within a species affects phytochemical composition is a fundamental question in botany. The ratio of two specialized metabolites in Cannabis sativa, tetrahydrocannabinol (THC) and cannabidiol (CBD), can be grouped into three main classes (THC-type, CBD-type, and intermediate type). We tested a genetic model associating these three groups with functional and nonfunctional alleles of the cannabidiolic acid synthase gene (CBDAS).

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Article Synopsis
  • MutY glycosylase helps fix DNA mistakes by removing adenines that are incorrectly paired with the oxidatively damaged guanine (OG), preventing potential mutations.
  • The study shows that specific parts of the MutY protein and the structure of OG are essential for the protein to recognize and repair these DNA errors effectively.
  • Findings suggest that problems with this detection process could be linked to early-onset colorectal cancer, paving the way for potential therapies targeting the MUTYH gene.
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A method has been developed to screen cannabis extracts for more than 1,000 pesticides and environmental pollutants using a gas chromatograph coupled to a high-resolution accurate mass quadrupole time-of-flight mass spectrometer (GC/Q-TOF). An extraction procedure was developed using acetonitrile with solid phase extraction cleanup. Before analysis, extracts were diluted 125:1 with solvent.

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Background: Cryopreservation is the only method allowing the safe and cost-effective long-term conservation of important germplasm. Recent use of the cryo-plate system has proven beneficial in further simplifying the cryopreservation protocols.

Objective: Developing an efficient protocol for the cryopreservation of axillary buds of Cannabis sativa elite cultivars (MX and V1-20) by the V-cryoplate droplet-vitrification technique.

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UV-DDB, a key protein in human global nucleotide excision repair (NER), binds avidly to abasic sites and 8-oxo-guanine (8-oxoG), suggesting a noncanonical role in base excision repair (BER). We investigated whether UV-DDB can stimulate BER for these two common forms of DNA damage, 8-oxoG and abasic sites, which are repaired by 8-oxoguanine glycosylase (OGG1) and apurinic/apyrimidinic endonuclease (APE1), respectively. UV-DDB increased both OGG1 and APE1 strand cleavage and stimulated subsequent DNA polymerase β-gap filling activity by 30-fold.

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In the original publication, table 2 contained data that should not have been included in table 2 and also was not discussed in the body of the manuscript.

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Through the potency monitoring program at the University of Mississippi supported by National Institute on Drug Abuse (NIDA), a total of 18108 samples of cannabis preparations have been analyzed over the last decade, using a validated GC/FID method. The samples are classified as sinsemilla, marijuana, ditchweed, hashish, and hash oil (now referred to as cannabis concentrate). The number of samples received over the last 5 years has decreased dramatically due to the legalization of marijuana either for medical or for recreational purposes in many US states.

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Terpenes are the major components of the essential oils present in various L. varieties. These compounds are responsible for the distinctive aromas and flavors.

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Many DNA repair enzymes, including the human adenine glycosylase MUTYH, require iron-sulfur (Fe-S) cluster cofactors for DNA damage recognition and subsequent repair. MUTYH prokaryotic and eukaryotic homologs are a family of adenine (A) glycosylases that cleave A when mispaired with the oxidatively damaged guanine lesion, 8-oxo-7,8-dihydroguanine (OG). Faulty OG:A repair has been linked to the inheritance of missense mutations in the MUTYH gene.

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A growing number of iron-sulfur (Fe-S) cluster cofactors have been identified in DNA repair proteins. MutY and its homologs are base excision repair (BER) glycosylases that prevent mutations associated with the common oxidation product of guanine (G), 8-oxo-7,8-dihydroguanine (OG) by catalyzing adenine (A) base excision from inappropriately formed OG:A mispairs. The finding of an [4Fe-4S] cluster cofactor in MutY, Endonuclease III, and structurally similar BER enzymes was surprising and initially thought to represent an example of a purely structural role for the cofactor.

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Base excision repair glycosylases locate and remove damaged bases in DNA with remarkable specificity. The MutY glycosylases, unusual for their excision of undamaged adenines mispaired to the oxidized base 8-oxoguanine (OG), must recognize both bases of the mispair in order to prevent promutagenic activity. Moreover, MutY must effectively find OG:A mismatches within the context of highly abundant and structurally similar T:A base pairs.

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Using state of the art spin polarized density functional theory, we report the stability and structural aspects of small magnetic clusters M(4) (M = Fe, Co, and Ni) inside an inert boron nitride nanotube [BNNT(10,0)]. The geometry optimization was carried out starting with various possible configurations [one-dimensional (1D) linear chain, two-dimensional (2D) planar rhombus, and three-dimensional (3D) tetrahedral], and the results reveal that the ground state geometry of M(4) cluster inside the nanotube favors 3D configuration over others. Moreover, these small clusters are found to retain their magnetic nature with a small reduction in the total magnetic moment even after encapsulation.

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The leather tanning industry is characterized by the production of different kinds of effluents, generated in each step of leather processing. These effluents have various chemical compounds which may cause toxicity and endocrine disruption and are thus known as endocrine disrupting chemicals (EDC). This study was aimed to examine the androgenic potential of leather industry effluents collected from northern region of India.

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Specific binding of Hg2+ to ouabain-sensitive Na(+)-K(+)-ATPase of rat liver plasma membrane was demonstrated with a Ka of 2.64 x 10(9) and Bmax of 1.6 nmole mg-1 protein.

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