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1.
Lab Chip ; 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39291871

ABSTRACT

Point-of-care (POC) platelet function analysis can enable timely and precise management of bleeding and clotting in emergency rooms, operation rooms and intensive care units. However, POC platelet testing is currently not commonly performed, due to the complexity of sample preparation and limitations of existing technologies. Here, we report the development of an integrated microfluidic multiple electrode aggregometry (µMEA) sensor which uses multi-frequency impedance measurement of an embedded microelectrode array to perform platelet aggregometry directly from whole blood, sensing and measuring platelet activation in a label-free manner and without requiring any additional sample preparation. Additionally, the sensor incorporates blood flow during the assay to account for physiological flow and shear conditions. We show that the impedance signal from the sensor can be used to accurately detect and quantify platelet aggregation in a label-free manner, which was further validated by simultaneous fluorometric measurement and visualization of platelet aggregation. Further, we optimized the sensitivity and repeatability of the sensor using its frequency response and demonstrated that the sensor could be used to characterize drug dose-response in antiplatelet therapy with a frequency-tunable dynamic range. We also demonstrate that the sensor provides high sensitivity to perform platelet aggregometry under thrombocytopenic or low platelet count conditions. The µMEA sensor could thus enable POC platelet function analysis across several clinical applications.

3.
Food Funct ; 14(10): 4569-4582, 2023 May 22.
Article in English | MEDLINE | ID: mdl-37099034

ABSTRACT

Understanding the mechanisms of food digestion is of paramount importance to determine the effect foods have on human health. Significant knowledge on the fate of food during digestion has been generated in healthy adults due to the development of physiologically-relevant in vitro digestion models. However, it appears that the performance of the oro-gastrointestinal tract is affected by ageing and that a model simulating the digestive conditions found in a younger adult (<65 years) is not relevant for an older adult (>65 years). The objectives of the present paper were: (1) to conduct an exhaustive literature search to find data on the physiological parameters of the older adult oro-gastrointestinal tract, (2) to define the parameters of an in vitro digestion model adapted to the older adult. International experts have discussed all the parameters during a dedicated workshop organized within the INFOGEST network. Data on food bolus properties collected in the older adult were gathered, including food particle size found in older adult boluses. In the stomach and small intestine, data suggest that significant physiological changes are observed between younger and older adults. In the latter, the rate of gastric emptying is slowed down, the pH of the stomach content is higher, the amount of secretions and thus the hydrolytic activities of gastric and intestinal digestive enzymes are reduced and the concentration of bile salts lower. The consensus in vitro digestion model of the older adult proposed here will allow significant progress to be made in understanding the fate of food in this specific population, facilitating the development of foods adapted to their nutritional needs. Nevertheless, better foundational data when available and further refinement of the parameters will be needed to implement the proposed model in the future.


Subject(s)
Digestion , Models, Biological , Humans , Aged , Consensus , Digestion/physiology , Gastrointestinal Tract/physiology , Stomach
4.
Philos Trans A Math Phys Eng Sci ; 381(2247): 20220158, 2023 May 15.
Article in English | MEDLINE | ID: mdl-36970825

ABSTRACT

Randomized clinical trials have been the mainstay of clinical research, but are prohibitively expensive and subject to increasingly difficult patient recruitment. Recently, there is a movement to use real-world data (RWD) from electronic health records, patient registries, claims data and other sources in lieu of or supplementing controlled clinical trials. This process of combining information from diverse sources calls for inference under a Bayesian paradigm. We review some of the currently used methods and a novel non-parametric Bayesian (BNP) method. Carrying out the desired adjustment for differences in patient populations is naturally done with BNP priors that facilitate understanding of and adjustment for population heterogeneities across different data sources. We discuss the particular problem of using RWD to create a synthetic control arm to supplement single-arm treatment only studies. At the core of the proposed approach is the model-based adjustment to achieve equivalent patient populations in the current study and the (adjusted) RWD. This is implemented using common atoms mixture models. The structure of such models greatly simplifies inference. The adjustment for differences in the populations can be reduced to ratios of weights in such mixtures. This article is part of the theme issue 'Bayesian inference: challenges, perspectives, and prospects'.


Subject(s)
Electronic Health Records , Humans , Bayes Theorem
7.
Exp Oncol ; 44(1): 7-16, 2022 05.
Article in English | MEDLINE | ID: mdl-35548961

ABSTRACT

Non-small cell lung cancer (NSCLC) is one of the most lethal malignancies accountings for nearly 80% of all lung cancer cases diagnosed and causing over one million deaths annually worldwide. The discovery of molecular alterations including driver mutations and gene fusions has led to innovation of numerous targeted therapies, which certainly provided an edge over the classical chemotherapeutic treatment regimens and improved survival of the patients. Despite all the breakthrough innovations, the five-year survival statistics has not improved the way it was expected, pointing the challenges and limitations of currently approved diagnostic methods and therapies. This review summarizes various innovative therapies, treatment regimens developed over the last two decades for NSCLC treatment and the current challenges and limitations in the NSCLC treatment landscape.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/therapy , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/therapy
8.
Bratisl Lek Listy ; 123(2): 110-119, 2022.
Article in English | MEDLINE | ID: mdl-35065586

ABSTRACT

Paracetamol is a popular and safe drug preferred by victims of pain or pyrexia; however, its overdose or abuse is a growing concern worldwide. Here the hepatoprotective effect of an ethnomedicinal plant Drynaria quercifolia against paracetamol­induced toxicity in murine model is demonstrated. This fern, native to tropical countries including the Northeast India, is used by local tribes to treat inflammatory conditions. Paracetamol 500 mg/kg body weight was orally administered on alternate days for a period of 21days to mimic a chronic overdose. Drynaria quercifolia acetone extract (DQA) treatment interspaced with paracetamol significantly decreased serum biomarkers of hepatotoxicity (ALT, AST and ALP) renal toxicity (urea, creatinine), lipid peroxidation level, histological damage in liver and kidney. The protein and mRNA expressions of the transcription factor, Nrf2, and its target antioxidant genes (SOD1, CAT and GST) as well as activities of these antioxidant enzymes were downregulated by paracetamol administration but significantly recovered following the DQA treatment (Tab. 3, Fig. 5, Ref. 31). Keywords: acetaminophen/paracetamol, Drynaria quercifolia, renal toxicity, hepatotoxicity, Nrf-2.


Subject(s)
Chemical and Drug Induced Liver Injury , Polypodiaceae , Acetaminophen/toxicity , Animals , Antioxidants/pharmacology , Chemical and Drug Induced Liver Injury/drug therapy , Chemical and Drug Induced Liver Injury/prevention & control , Liver , Mice , Plant Extracts/pharmacology
9.
J Biotechnol ; 345: 40-46, 2022 Feb 10.
Article in English | MEDLINE | ID: mdl-34952091

ABSTRACT

One of the exciting aspects of different nanomaterials in biomedical applications is the delivery of a wide range of anti-cancer drugs to mitigate their negative side effects via precise targeting of the tumor cells. In the present study, the DFT B3LYP/6-31G (d, p) level of theory was used to evaluate the capabilities of raw BC2N nanotubes (BC2NNTs) and functionalized BC2NNTs nanostructures as a carrier for an anti-cancer drug (i.e., 3-allyl-2-hydantoin (3-ASH)). It was specified that the existing interaction between 3-ASH and BC2N nanotubes is weak (-10.97 kcal mol-1). Therefore, the functionalized BC2NNTs were investigated for 3-ASH interaction. According to our computations, compared with raw BC2NNTs, the role of hydrogen bonds between 3-ASH molecules' active sites and carboxyl-functionalized BC2NNTs in the complexes' fixation, adsorption, and thermodynamic energy is of great importance. A considerable transfer of charge between 3-ASH molecule to the functionalized BC2NNTs was detected via MEP, NBO, and fractional charge transfer analysis. Also, it was found that these nanostructures have high stability on the water medium while their solvation energies have negative values. This negative value is beneficial for the applications of 3-ASH drug delivery. The present work proposes a new method to load 3-ASH drugs with a high density on BC2NNTs' surfaces.


Subject(s)
Hydantoins , Nanotubes , Neoplasms , Pharmaceutical Preparations , Drug Delivery Systems , Humans
10.
J Magn Reson ; 331: 107021, 2021 10.
Article in English | MEDLINE | ID: mdl-34563333

ABSTRACT

The emergence of a new class of optically polarizable electronic spins in diamond, nitrogen vacancy (NV) defect centers, has opened interesting new avenues for dynamic nuclear polarization. Here we review methods for the room-temperature hyperpolarization of lattice 13C nuclei using optically pumped NV centers, focusing particular attention to a polarization transfer via rotating-frame level anti-crossings. We describe special features of this optical DNP mechanism at low-field, in particular, its deployability to randomly oriented diamond nanoparticles. In addition, we detail methods for indirectly obtaining high-resolution NV ESR spectra via hyperpolarization readout. These mechanistic features provide perspectives for interesting new applications exploiting the optically generated 13C hyperpolarization.

12.
Eur J Pharm Sci ; 161: 105770, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-33610738

ABSTRACT

Although mechanistic numerical simulations can offer great insights into a process, they are limited with respect to resolved process time. While statistical models provide long-term predictability, determining the underlying probability distributions is often challenging. In this work, detailed CFD-DEM simulations of a pharmaceutical Wurster coating process for microspheres are used to evaluate the input parameters for a novel Monte-Carlo simulation approach. The combined strengths of both modeling approaches make it possible to predict the coating mass and thickness distributions over the entire process time. It was observed that smaller beads receive a thicker coating layer since they pass the spray zone closer to the nozzle. Moreover, it was established that, in contrast to the airflow rate, the spray rate has a great impact on the inter-particle coating variability. A stochastic model was developed to investigate the relative contribution of coating layer variability and fill weight variability to the product non-uniformity in a capsule filling process of Multiple Unit Pellet Systems (MUPS).


Subject(s)
Pharmaceutical Preparations , Computer Simulation , Drug Compounding , Monte Carlo Method , Particle Size , Technology, Pharmaceutical
13.
J Mol Model ; 27(3): 72, 2021 Feb 05.
Article in English | MEDLINE | ID: mdl-33544257

ABSTRACT

The density functional theory (DFT) was used to study the interaction of cysteine amino acid with (8, 0) zigzag single-walled BC2N nanotubes (BC2NNTs) both in gas and solvent phases. The interaction between cysteine amino acid and BC2NNTs is found to be energetically favorable in both phases. Based on the calculations of solvation energy, it can be seen that the dissolution of BC2NNT/amino acid complex in water is spontaneous. During the functionalization process, the quantum molecular descriptor and the energy of adsorption changed significantly. Findings suggest that the cysteine amino acid can be considerably adsorbed chemically onto the surface of BC2NNTs. Based on the Eg values obtained, the cysteine molecule caused a reduction in the Eg value, which also increased the reactivity and conductivity of functionalized BC2NNTs. According to the findings of chemical hardness, the kinetic stability of the functionalized nanotubes was better than pure nanotubes. As a result of this approach, Eg values are indicative of high propensity reaction and electron transfer. Our findings have shown that BC2NNTs can function as an appropriate drug delivery system for cysteine amino acid within biological systems for the adsorption of the drug and controlled drug release.


Subject(s)
Cysteine/chemistry , Density Functional Theory , Nanotubes, Carbon/chemistry , Adsorption , Amino Acids/chemistry , Models, Molecular , Structure-Activity Relationship
14.
Clin Exp Immunol ; 201(3): 279-288, 2020 09.
Article in English | MEDLINE | ID: mdl-32443171

ABSTRACT

Solid tumors elicit suppressive T cell responses which impair antigen-presenting cell (APC) functions. Such immune suppression results in uncontrolled tumor growth and mortality. Addressing APC dysfunction, dendritic cell (DC)-mediated anti-tumor vaccination was extensively investigated in both mice and humans. These studies never achieved full resistance to tumor relapse. Herein, we describe a repetitive RM-1 murine tumor rechallenge model for recurrence in humans. Using this newly developed model, we show that priming with tumor antigen-pulsed, Toll-like receptor (TLR)2 ligand-activated DCs elicits a host-protective anti-tumor immune response in C57BL/6 mice. Upon stimulation with the TLR2 ligand peptidoglycan (PGN), the tumor antigen-pulsed DCs induce complete resistance to repetitive tumor challenges. Intra-tumoral injection of PGN reduces tumor growth. The tumor resistance is accompanied by increased expression of interleukin (IL)-27, T-box transcription factor TBX21 (T-bet), IL-12, tumor necrosis factor (TNF)-α and interferon (IFN)-γ, along with heightened cytotoxic T lymphocyte (CTL) functions. Mice primed four times with PGN-stimulated tumor antigen-pulsed DCs remain entirely resistant to repeat challenges with RM-1 tumor cells, suggesting complete prevention of relapse and recurrence of tumor. Adoptive transfer of T cells from these mice, which were fully protected from RM-1 rechallenge, confers anti-tumor immunity to syngeneic naive recipient mice upon RM-1 challenge. These observations indicate that PGN-activated DCs induce robust host-protective anti-tumor T cells that completely resist tumor growth and recurrence.


Subject(s)
Cancer Vaccines/immunology , Dendritic Cells/immunology , Immunotherapy, Adoptive/methods , Prostatic Neoplasms/immunology , T-Lymphocytes, Cytotoxic/immunology , Animals , Antigens, Neoplasm/immunology , Antigens, Neoplasm/metabolism , Cytokines/metabolism , Dendritic Cells/transplantation , Disease Models, Animal , Humans , Inflammation Mediators/metabolism , Male , Mice , Mice, Inbred C57BL , Neoplasm Recurrence, Local , Peptidoglycan/metabolism , Toll-Like Receptor 2/agonists , Tumor Burden
15.
J Phys Condens Matter ; 32(16): 165801, 2020 Apr 17.
Article in English | MEDLINE | ID: mdl-31899900

ABSTRACT

The ability to create atomically perfect, epitaxial heterostructures of correlated complex perovskite oxides using state-of-art thin film deposition techniques has generated new physical phenomena at engineered interfaces. Here we report on the impact of growth kinetics on the magnetic structure and exchange coupling at the interface in heterostructures combining layers of antiferromagnetic La1/3Sr2/3FeO3 (LSFO) and ferromagnetic La2/3Sr1/3MnO3 (LSMO) on (0 0 1)-oriented SrTiO3 (STO) substrates. Two growth orders are investigated, (a) LSMO/LSFO/STO(0 0 1) and (b) LSFO/LSMO/STO(0 0 1), where the LSFO layer is grown by molecular beam epitaxy and the LSMO layer by high oxygen pressure sputtering. The interface has been investigated using electron microscopy and polarized neutron reflectometry. Interdiffusion over seven monolayers is observed in LSMO/LSFO (a) with an almost 50% reduction in magnetization at the interface and showing no exchange coupling. However, the exchange bias effect ([Formula: see text] mT at 10 K) could be realized when the interface is atomically sharp, as in LSFO/LSMO (b). Our study therefore reveals that, even for well ordered and lattice-matched structures, the kinetics involved in the growth processes drastically influences the interface quality with a strong correlation to the magnetic properties.

16.
J Phys Condens Matter ; 32(8): 085703, 2020 Feb 20.
Article in English | MEDLINE | ID: mdl-31469094

ABSTRACT

Depth resolved positron annihilation spectroscopy (PAS) has been employed to characterize the 1.2 MeV Ar and 800 keV O ion beam induced defects in ZnO. The first extraordinary result was the observation of defects in ion beam irradiated ZnO beyond the maximum penetration depth of the respective ions. The positron annihilation results revealed the formation of vacancy clusters consisting of both VZn and VO in ZnO which are saturated at a threshold radiation dose (defined as nuclear energy loss, Sn × fluence). From the photoluminescence (PL) spectra it has been observed that the PL intensity at the band edge degraded with the increase of open volume defects in ZnO. The evolution of the 2.4 eV PL, which is linked with the oxygen vacancies, is more significant due to Ar irradiation than the oxygen irradiation.

17.
RSC Adv ; 10(59): 35966-35978, 2020 Sep 28.
Article in English | MEDLINE | ID: mdl-35517101

ABSTRACT

The design of stable and high performance metal free bifunctional electrocatalysts is a necessity in alkaline zinc-air batteries for oxygen reduction and evolution reaction. In the present work co-doped carbon materials have been developed from polymeric precursors with abundant active sites to achieve bifunctional activity. A 3-dimensional microporous nitrogen-carbon (NC) and co-doped nitrogen-sulfur-carbon (NSC) and nitrogen-phosphorus-carbon (NPC) were synthesized using poly(2,5-benzimidazole) as an N containing precursor. The obtained sheet like structure shows outstanding ORR and OER performance in alkaline systems with excellent stability compared to Pt/C catalyst. The doped heteroatom in the carbon is expected to have redistributed the charge around heteroatom dopants lowering the ORR potential and modifying the oxygen chemisorption mode thereby weakening the O-O bonding and improving the ORR activity and overall catalytic performance. The bifunctional activity (ΔE = E j=10 - E 1/2) of an air electrode for NPC, NSC, NC and Pt/C is 0.82 V, 0.87 V, 1.06 V and 1.03 V respectively, and the NPC value is smaller than most of the reported metal and non-metal based electrocatalysts. The ORR (from onset potential) and OER (10 mA cm-2) overpotential for NPC, NSC, and NC is (290 mV, 410 mV), (310 mV, 450 mV) and (340 mV, 600 mV) respectively. In the prepared catalyst the NPC exhibited higher ORR and OER activity (NPC > NSC > NC). The doping of P in NPC is found to have a great influence on the microstructure and therefore on the ORR and OER activity.

18.
J Appl Microbiol ; 126(6): 1742-1750, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30817048

ABSTRACT

AIMS: Hot springs have always drawn attention due to their unique chemical richness and the presence of different microbial communities. The use of hot spring bacteria in concrete technology is our primary focus; isolation of an alkaliphilic bacterium from the Bakreshwar hot springs having longer survival and better efficacy towards cementitious environment was the basis of our study's design. METHODS AND RESULTS: A novel facultative anaerobic and highly alkaliphilic bacterial strain (BKH4; GenBank accession no. KX622782) belonging to the family 'Bacillaceae' and homologous (99%) with Lysinibacillus fusiformis was isolated from Bakreshwar hot springs. The isolated coccoid-type Gram-positive bacterium grows well in a defined semi-synthetic medium (pH 12·0 and 65°C). This bacterium survives for more than a month and shows better efficacy in enhancing compressive strengths (>50%), ultrasonic pulse velocity (>25%) and durability of the cementitious mortar when incorporated at a concentration of 104  cells per ml of water used. CONCLUSION: The novel bacterium BKH4 is more effective for the enhancement of the bioconcrete properties. SIGNIFICANCE AND IMPACT OF THE STUDY: BKH4 bacterium will add a new dimension to future concrete technology for its usefulness in strength enhancement and durability due to its alkaliphilic nature and longer survival within a cementitious environment.


Subject(s)
Alkalies/metabolism , Bacillaceae/physiology , Biotechnology , Construction Materials/microbiology , Hot Springs/microbiology , Bacillaceae/genetics , Bacillaceae/metabolism , Compressive Strength , DNA, Bacterial/genetics , Hot Temperature , Hydrogen-Ion Concentration , Nucleic Acid Hybridization , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
19.
Mymensingh Med J ; 28(1): 150-156, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30755564

ABSTRACT

Several mechanisms have been proposed to explain the symptoms of functional dyspepsia but actual pathogenesis is still poorly understood. Recent studies support duodenal abnormality to be the most important causal link to explain symptoms and to understand abnormal pathophysiology of functional dyspepsia. The aim of this prospective observational study is to compare eosinophil count in duodenal mucosa between patients with functional dyspepsia and control subjects without dyspepsia and was done at the department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from December 2015 to December 2016. Total 42 patients of functional dyspepsia based on Bangla validated version of ROME III criteria and 42 controls who were referred for upper gastrointestinal endoscopy for reasons other than dyspepsia were included. Biopsy specimens were collected from the second part (D2) of the duodenum of all participants. Eosinophil count was quantitatively evaluated by hematoxylin and eosin staining and expressed in numbers per 5 HPF. Significantly increased duodenal eosinophil count was found in functional dyspepsia group than non dyspeptic patients (22.78±08.78 vs. 14.90±10.70, p=0.001). Higher duodenal eosinophil count was found in patients with postprandial distress syndrome. Increased duodenal eosinophil count was found in patient of functional dyspepsia. It requires further large scale multicenter studies to establish duodenal eosinophilia as a biomarker of functional dyspepsia.


Subject(s)
Duodenum/metabolism , Dyspepsia/metabolism , Eosinophils/metabolism , Adult , Bangladesh , Case-Control Studies , Duodenum/pathology , Dyspepsia/pathology , Eosinophils/pathology , Humans , Prospective Studies
20.
Oncogene ; 38(10): 1734-1750, 2019 03.
Article in English | MEDLINE | ID: mdl-30353164

ABSTRACT

Migration of human glioma cells (hGCs) within the brain parenchyma makes glioblastoma one of the most aggressive and lethal tumors. Studies of the cellular and molecular mechanisms underlying hGC migration are hindered by the limitations of existing glioma models. Here we developed a dorsal root ganglion axon-oligodendrocyte-hGC co-culture to study in real time the migration and interaction of hGCs with their microenvironment. hGCs interact with myelinated and non-myelinated axons through the formation of pseudopodia. Isolation of pseudopodia-localized polysome-bound RNA reveals transcripts of Lck, Paxillin, Crk-II, and Rac1 that undergo local translation. Inhibition of Lck phosphorylation using a small-molecule inhibitor (Lck-I), blocks the phosphorylation of Paxillin and Crk-II, the formation of pseudopodia and the migration of hGCs. In vivo intraventricular administration of the Lck-I using an orthotopic xenograft glioma model, results in statistically significant inhibition of tumor size and significant down-regulation of Nanog-targeted genes, which are associated with glioblastoma patient survival. Moreover, treatment of human glioma stem cells (hGSCs) with Lck-I, results in significant inhibition of self-renewal and tumor-sphere formation. The involvement of Lck in different levels of glioma malignant progression, such as migration, tumor growth, and regulation of cancer stemness, makes Lck a potentially important therapeutic target for human glioblastomas.


Subject(s)
Brain Neoplasms/metabolism , Glioma/metabolism , Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/genetics , Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/metabolism , Pseudopodia/genetics , Pyrazoles/administration & dosage , Pyrimidines/administration & dosage , Animals , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Cell Movement/drug effects , Cells, Cultured , Coculture Techniques , Ganglia, Spinal/cytology , Ganglia, Spinal/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Glioma/drug therapy , Glioma/genetics , Humans , Male , Mice , Neoplastic Stem Cells/drug effects , Oligodendroglia/cytology , Oligodendroglia/metabolism , Paxillin/genetics , Paxillin/metabolism , Phosphorylation/drug effects , Proto-Oncogene Proteins c-crk/genetics , Proto-Oncogene Proteins c-crk/metabolism , Pseudopodia/metabolism , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Xenograft Model Antitumor Assays , rac1 GTP-Binding Protein/genetics , rac1 GTP-Binding Protein/metabolism
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