Development of an HPLC-PDA Method for the Simultaneous Estimation of Three Antibiotics in Pharmaceutical Formulations and Bovine Milk and Health Risk Assessment.

A simple new, rapid, sensitive, and cost-effective HPLC-PDA method was developed and validated for the determination of tetracycline (TC), oxytetracycline (OTC), and ciprofloxacin (CIP) simultaneously. Chromatographic separations were carried out using a reversed-phase Shim-pack GIS C18 column (4.60 × 250.00 mm; 5.00 µm) at 30°C. Oxalic acid (0.05 M), acetonitrile, and methanol were used as mobile phase under gradient elution conditions at the flow rate of 1.50 mL min-1. Detection wavelength was set at 330 nm. An aliquot of 20.00 µL solution was injected, and three drugs were eluted within 7.39 ± 0.05 min. As per ICH guidelines linearity, recovery, accuracy, precision, selectivity, specificity, sensitivity, stability, column efficiency, system suitability, and robustness were determined for the validation of the proposed method. Calibration curves were linear over a studied concentration range of 8.00 µg mL-1 with a correlation coefficient (r) of 0.999 for all drugs. Relative standard deviation (RSD) for intra- and interday precision was found less than 2.87% and 3.22%, respectively, indicating the method to be reproducible. The proposed method has been suitably applied for the estimation of TC, OTC, and CIP in pharmaceutical formulation and milk samples collected from local market in Bangladesh. Among 15 milk samples analyzed, most of the cases (more than 50%) TC, OTC, and CIP were detected above maximum residue levels (MRLs) though no significant toxicological effect on the health of consumers in the study area was identified.

The interrelationship between cerebral ischemic stroke and glioma: a comprehensive study of recent reports.

Glioma and cerebral ischemic stroke are two major events that lead to patient death worldwide. Although these conditions have different physiological incidences, ~10% of ischemic stroke patients develop cerebral cancer, especially glioma, in the postischemic stages. Additionally, the high proliferation, venous thrombosis and hypercoagulability of the glioma mass increase the significant risk of thromboembolism, including ischemic stroke. Surprisingly, these events share several common pathways, viz. hypoxia, cerebral inflammation, angiogenesis, etc., but the proper mechanism behind this co-occurrence has yet to be discovered. The hypercoagulability and presence of the D-dimer level in stroke are different in cancer patients than in the noncancerous population. Other factors such as atherosclerosis and coagulopathy involved in the pathogenesis of stroke are partially responsible for cancer, and the reverse is also partially true. Based on clinical and neurosurgical experience, the neuronal structures and functions in the brain and spine are observed to change after a progressive attack of ischemia that leads to hypoxia and atrophy. The major population of cancer cells cannot survive in an adverse ischemic environment that excludes cancer stem cells (CSCs). Cancer cells in stroke patients have already metastasized, but early-stage cancer patients also suffer stroke for multiple reasons. Therefore, stroke is an early manifestation of cancer. Stroke and cancer share many factors that result in an increased risk of stroke in cancer patients, and vice-versa. The intricate mechanisms for stroke with and without cancer are different. This review summarizes the current clinical reports, pathophysiology, probable causes of co-occurrence, prognoses, and treatment possibilities.

Cerebral ischemic stroke: cellular fate and therapeutic opportunities.

In cerebral tissues, due to continuous and high metabolic demand, energy is produced exclusively by mitochondrial oxidative phosphorylation (OXPHOS). Obstruction of blood flow leads to cerebral ischemia, hypoxia and decreased cellular ATP production. The reactive oxygen species (ROS) generated as by-product of OXPHOS alter many intracellular signaling pathways and result in damaged cellular components. Under such hypoxic conditions, a key factor known as hypoxia inducible factor 1 (HIF1) is stabilized and activated and such activation induces expression of a defined set of target genes which are required for cell survival and angiogenesis. Reperfusion that follows such ischemia alters signaling pathways which are involved in cellular fate. Here, we will review the role of ROS, HIF-1 alpha and other signaling network in mitochondrial dysfunction and cell fate determination in ischemia-reperfusion models in the brain. We will also address both current and future therapeutic strategies for clinical significance that are being developed for treatment of cerebral ischemia.

Emerging insights into HAUSP (USP7) in physiology, cancer and other diseases.

Herpesvirus-associated ubiquitin-specific protease (HAUSP) is a USP family deubiquitinase. HAUSP is a protein of immense biological importance as it is involved in several cellular processes, including host-virus interactions, oncogenesis and tumor suppression, DNA damage and repair processes, DNA dynamics and epigenetic modulations, regulation of gene expression and protein function, spatio-temporal distribution, and immune functions. Since its discovery in the late 1990s as a protein interacting with a herpes virus regulatory protein, extensive studies have assessed its complex roles in p53-MDM2-related networks, identified numerous additional interacting partners, and elucidated the different roles of HAUSP in the context of cancer, development, and metabolic and neurological pathologies. Recent analyses have provided new insights into its biochemical and functional dynamics. In this review, we provide a comprehensive account of our current knowledge about emerging insights into HAUSP in physiology and diseases, which shed light on fundamental biological questions and promise to provide a potential target for therapeutic intervention.