Impact of 6-hydroxydopamine on agonist-induced human platelet functional parameters: An explanation for platelet impairment in Parkinson's disease.

Parkinson's disease (PD) is the second-most prevalent neurodegenerative disease worldwide, which worsens with advancing age. It is a common movement disorder and is often associated with several vascular diseases with decreased stroke frequency. Circulating platelets substantially regulate vascular complications, including stroke, and share striking similarities with PD neurons. Although structural alterations in platelets are well-documented in PD, their functional parameters remain unclear. This study aimed to investigate the functional abnormalities in platelets associated with PD by evaluating key functional aspects such as adhesion, activation, secretion, aggregation, and clot retraction. To achieve this, we treated human blood platelets with 6-hydroxydopamine or 6-OHDA, that selectively destroys dopaminergic neurons, thereby creating an in vitro experimental model that closely resembles the pathogenic environment in PD, and examine its impact on platelet functions. In our study, platelet adhesion was assessed and further evaluated by a microplate reader, activation and secretion by a flow cytometer, aggregation by aggregometer, and clot retraction by Sonoclot. Phase-contrast and confocal microscopic studies further verified the results from the above experiments. Our findings showed that 6-OHDA treatment significantly inhibited thrombin (a platelet agonist)-induced functions, including adhesion, activation, aggregation, secretion, and clot retraction in human-washed platelets. In summary, this research provides pioneering evidence that 6-OHDA induces abnormal platelet functions, shedding light on the previously unexplored processes by which 6-OHDA affects platelet activity.

The Applications of 2D Materials for Electrochemical Biosensing, Drug Delivery, and Environmental Monitoring.

Two-dimensional (2D) nanomaterials (NMs) have diverse mechanical, chemical and optical properties due to which they have received a lot of attention in various fields such as biosensors, imaging, tissue engineering, drug delivery, etc. A thorough understanding of the synthetic procedure, physical properties and electrochemical properties of 2D materials will be quite useful in the development of novel and high-efficient electrocatalysts for the electroanalytical application of our interest. This review article summarises the synthesis and application of graphene, graphitic carbon nitride, transition metal dichalcogenides and phosphorene for electrochemical biosensing, drug delivery application and environmental monitoring. Numerous synthetic approaches which have been adopted to synthesize the 2D materials have been covered and discussed. Also, the reasons behind the catalytic activity of various types of 2D materials and their application as electrode modifier for the development of an efficient biosensor for the point-of-care analysis of biomolecule and drug delivery and environmental monitoring have been discussed in detail. This review article will give valuable information and future insights to the researchers working in the field of biosensor, drug delivery and environmental monitoring. We anticipate that this review may be of significance for the field to understand the properties as well as the electroanalytical applications of 2D materials, especially in biosensing, drug and environmental monitoring.

Role of ACE inhibitors in anthracycline-induced cardiotoxicity: A randomized, double-blind, placebo-controlled trial.

BACKGROUND: Several measures including drugs have been tried to reduce anthracycline cardiotoxicity. The lack of randomized trials prompted this study to assess the role of an angiotensin converting enzyme (ACE) inhibitor (enalapril) in anthracycline-induced cardiotoxicity in children with hematological malignancies. METHODS: A randomized, double-blind, placebo-controlled trial was conducted on 84 patients with leukemia (41) and lymphoma (43) who received anthracyclines (doxorubicin and/or daunorubicin) at cumulative dose ≥200 mg/m2 . The patients were randomized to receive either enalapril [group A (n = 44)] or placebo [group B (n = 40)] for 6 months. Left ventricular ejection fraction (LVEF) and cardiac biomarkers (cardiac troponin I [cTnI], probrain natriuretic peptide [proBNP], and creatine kinase MB [CK-MB]) were assessed at baseline and 6 months. The primary outcome was a measured decrease in LVEF (≥20%). Secondary outcome measures were changes in cardiac biomarkers and the development of heart failure or arrhythmias. RESULTS: LVEF decreased in both groups at 6 months, more so in group B (62.25 ± 5.49 vs 56.15 ± 4.79, P < 0.001). A ≥20% decrease was seen in 3 patients in group B but none in group A (P = 0.21). Cardiac biomarkers increased more in group B at 6 months, and the increase was significant for proBNP (49.60 ± 35.97 vs 98.60 ± 54.24, P < 0.001) and cTnI (0.01 ± 0.00 vs 0.011 ± 0.003, P = 0.035) but not significant for CK-MB (1.08 ± 0.18 vs 1.21 ± 0.44, P = 0.079). In group A, 9.1% of the patients showed an increase in proBNP level ≥100 compared with 37.5% in group B (P < 0.001). No patient developed heart failure or arrhythmia. CONCLUSION: Enalapril has a role in reducing cardiac toxicity after anthracycline administration.

Rosai-Dorfman disease with exclusive intra-abdominal lymphadenopathy masquerading as Wilkie's syndrome.

Rosai-Dorfman disease is a rare histiocytic proliferative disorder with a distinctive microscopic appearance. Patients usually present with nonspecific symptoms and massive cervical lymphadenopathy. Exclusive involvement of intra-abdominal lymph nodes is unusual and presentation mimicking Wilkie's syndrome due to compression of the third part of the duodenum by enlarged retroduodenal lymph nodes is rare. This entity should be included in the differential diagnosis with infectious, granulomatous and malignant causes of intra-abdominal lymphadenopathy. We highlight an uncommon presentation and discuss the challenges in the diagnosis and management of Rosai-Dorfman disease.

Melatonin regulates splenocytes proliferation via IP3-dependent intracellular Ca2+ release in seasonally breeding bird, Perdicula asiatica.

Melatonin plays an important role in the immune regulation of birds. Both endogenous and exogenous melatonin modulates lymphocyte proliferation via its specific membrane receptors, Mel(1a), Mel(1b) and Mel(1c), though the mechanisms behind this process are poorly understood. We investigated the differences in melatonin membrane receptor Mel(1a), Mel(1b) and Mel(1c) expression by western blot and reverse transcription reaction and the in vitro effect of melatonin on the intracellular Ca(2+) concentration ([Ca2+]i) in splenocytes of the Indian Jungle Bush Quail, Perdicula asiatica. We used a non-selective melatonin receptor antagonist for Mel(1a) and Mel(1b), luzindole, and the selective Mel(1b) blocker, 4P-PDOT to check the specific role of melatonin receptor on ([Ca2+]i). The expression of Mel(1a), Mel(1b) and Mel(1c) receptors mRNA and protein was upregulated by melatonin (10(-7) M) with a significant high rise in ([Ca2+]i), which was differentially blocked by supplementation of antagonist, luzindole (10(-7) M) and 4P-PDOT (10(-7) M). Furthermore, we noted in vitro effect of melatonin and 2-aminoethoxydiphenyl borate (2-APB), a cell-permeable antagonist of inositol 1, 4, 5-trisphosphate (IP3) receptor to check the rise in ([Ca2+]i) through the IP3 pathway. Significantly low ([Ca2+]i) was noted in melatonin and 2-APB pretreated splenocytes when compared with splenocytes where 2-APB was absent. Thus, our data suggest that melatonin through its membrane receptor induced the elevation of ([Ca2+]i) via IP(3)-dependent pathway for splenocyte proliferation in P. asiatica.

Bioavailability enhancement of poorly water soluble and weakly acidic new chemical entity with 2-hydroxy propyl-beta-cyclodextrin: selection of meglumine, a polyhydroxy base, as a novel ternary component.

The purpose of the present study was to investigate the influence of a polyhydroxy base, N-acetyl glucamine (also know as Meglumine), as a ternary component on the complexation of DRF-4367, a poorly water-soluble and weakly acidic anti-inflammatory molecule, with 2-hydroxypropyl-beta-cyclodextrin (HPbetaCD). The molecular inclusion of DRF-4367 with HPbetaCD alone and in combination with ternary component was aimed at improvement in solubility and, subsequently, dissolution rate-limited oral bioavailability. The solid complexes of DRF-4367 and HPbetaCD with or without meglumine (binary and ternary systems, respectively) were prepared as coevaporated product in different stoichiometric ratios and compared against physical mixture. The formation of inclusion complexes was confirmed by using classical instrumental techniques. Phase solubility studies suggested that meglumine was responsible for solubility improvement via multiple factors rather than just providing a favorable pH. Mechanisms and factors governing solubility enhancement were investigated by using phase solubility and thermodynamic parameters. The complexation of DRF-4367 with HPbetaCD is thermodynamically favored because the Gibbs free energies of transfer of the drug to the cyclodextrin cavity are negative. The solubilization efficiency and stability were further improved while retaining the favorable Gibbs free energies of transfer with the addition of meglumine. Inclusion ternary complex of DRF-4367 with HPbetaCD and meglumine showed significant improvement in dissolution compared with uncomplexed drug and binary system. Moreover, the phenomena of reprecipitation observed with binary system during dissolution could be avoided with meglumine as an enabling ternary component. This improved physicochemical behavior of ternary complex with the novel inclusion of a polyhydroxy base translated into an enhanced oral bioavailability of DRF-4367 compared with either uncomplexed drug or nanosuspension.