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1.
J Pharm Bioallied Sci ; 16(Suppl 2): S1792-S1794, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38882742

ABSTRACT

Background: Orthodontic treatment often spans several months or even years, which can be burdensome for patients. Biomodulation techniques have emerged as potential strategies to expedite orthodontic tooth movement. Materials and Methods: A randomized clinical trial was conducted with a sample of 60 orthodontic patients, aged 12-30 years, requiring fixed appliance therapy. Patients were randomly assigned to either the biomodulation group (n = 30) or the control group (n = 30). The biomodulation group received low-level laser therapy (LLLT) along with traditional orthodontic treatment, while the control group received conventional orthodontic treatment without LLLT. Treatment duration, pain perception, and orthodontic tooth movement were assessed during the study period. Results: The results demonstrated a significant reduction in treatment duration in the biomodulation group compared to the control group. The biomodulation group exhibited a 30% reduction in overall treatment time, with an average treatment duration of 8.4 months, while the control group required an average of 12 months (P < 0.001). Pain perception during orthodontic adjustments was lower in the biomodulation group. Additionally, biomodulation was associated with a statistically significant increase in the rate of tooth movement, as evidenced by a 20% reduction in the time required to achieve desired tooth alignment (P < 0.01). Conclusion: Biomodulation through low-level laser therapy represents a promising adjunct to traditional orthodontic treatment, significantly accelerating tooth movement and reducing treatment duration.

2.
Brain ; 147(5): 1914-1925, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38181433

ABSTRACT

Autologous bone marrow mononuclear cells (BMMNCs) infused after severe traumatic brain injury have shown promise for treating the injury. We evaluated their impact in children, particularly their hypothesized ability to preserve the blood-brain barrier and diminish neuroinflammation, leading to structural CNS preservation with improved outcomes. We performed a randomized, double-blind, placebo-sham-controlled Bayesian dose-escalation clinical trial at two children's hospitals in Houston, TX and Phoenix, AZ, USA (NCT01851083). Patients 5-17 years of age with severe traumatic brain injury (Glasgow Coma Scale score ≤ 8) were randomized to BMMNC or placebo (3:2). Bone marrow harvest, cell isolation and infusion were completed by 48 h post-injury. A Bayesian continuous reassessment method was used with cohorts of size 3 in the BMMNC group to choose the safest between two doses. Primary end points were quantitative brain volumes using MRI and microstructural integrity of the corpus callosum (diffusivity and oedema measurements) at 6 months and 12 months. Long-term functional outcomes and ventilator days, intracranial pressure monitoring days, intensive care unit days and therapeutic intensity measures were compared between groups. Forty-seven patients were randomized, with 37 completing 1-year follow-up (23 BMMNC, 14 placebo). BMMNC treatment was associated with an almost 3-day (23%) reduction in ventilator days, 1-day (16%) reduction in intracranial pressure monitoring days and 3-day (14%) reduction in intensive care unit (ICU) days. White matter volume at 1 year in the BMMNC group was significantly preserved compared to placebo [decrease of 19 891 versus 40 491, respectively; mean difference of -20 600, 95% confidence interval (CI): -35 868 to -5332; P = 0.01], and the number of corpus callosum streamlines was reduced more in placebo than BMMNC, supporting evidence of preserved corpus callosum connectivity in the treated groups (-431 streamlines placebo versus -37 streamlines BMMNC; mean difference of -394, 95% CI: -803 to 15; P = 0.055), but this did not reach statistical significance due to high variability. We conclude that autologous BMMNC infusion in children within 48 h after severe traumatic brain injury is safe and feasible. Our data show that BMMNC infusion led to: (i) shorter intensive care duration and decreased ICU intensity; (ii) white matter structural preservation; and (iii) enhanced corpus callosum connectivity and improved microstructural metrics.


Subject(s)
Bone Marrow Transplantation , Brain Injuries, Traumatic , Transplantation, Autologous , Humans , Child , Brain Injuries, Traumatic/therapy , Male , Female , Adolescent , Double-Blind Method , Child, Preschool , Bone Marrow Transplantation/methods , Transplantation, Autologous/methods , Magnetic Resonance Imaging , Treatment Outcome , Leukocytes, Mononuclear/transplantation , Bayes Theorem
3.
Cytotherapy ; 26(2): 194-200, 2024 02.
Article in English | MEDLINE | ID: mdl-38127031

ABSTRACT

BACKGROUND AIMS: Mesenchymal stromal cells (MSCs) are multipotent adult cells that can be isolated from tissues including bone marrow [MSC(BM)], adipose [MSC(AT)] and umbilical cord [MSC(CT)]. Previous studies have linked expression of tissue factor (TF) on MSC surfaces to a procoagulant effect. Venous thromboembolism (VTE), immediate blood-mediated inflammatory reaction (IBMIR) and microvascular thrombosis remain a risk with intravascular MSC therapy. We examined the effect of low molecular weight heparin (LMWH) on clinical-grade MSCs using calibrated automated thrombography (CAT). METHODS: Clinical grade MSC(BM)s, MSC(AT)s and MSC(CT)s harvested at passage 4 were added to normal pooled plasma (NPP) to a final concentration of either 400 000 or 50 000 cells/mL. LMWH was added to plasma in increments of 0.1 U/mL. Thrombin generation (TG) was measured using CAT. Flow cytometry was conducted on the cells to measure MSC phenotype and TF load. RESULTS: Presence of MSCs decreased lag time and increased peak TG. All cell lines demonstrated a dose response to LMWH, with MSC(AT) demonstrating the least thrombogenicity and most sensitivity to LMWH. TG was significantly reduced in all cell lines at doses of 0.2 U/mL LMWH and higher. DISCUSSION: All MSC types and concentrations had a decrease in peak thrombin and TG with increasing amounts of LMWH. While this in vitro study cannot determine optimal dosing, it suggests that LMWH can be effectively used to lower the risk of VTE associated with intravascular administration of MSCs. Future in vivo work can be done to determine optimal dosing and effect on IBMIR and VTE.


Subject(s)
Coagulants , Thrombosis , Venous Thromboembolism , Adult , Humans , Heparin, Low-Molecular-Weight/pharmacology , Heparin, Low-Molecular-Weight/therapeutic use , Venous Thromboembolism/drug therapy , Coagulants/therapeutic use , Thrombin/therapeutic use , Heparin/therapeutic use
4.
Acta Neuropathol Commun ; 11(1): 168, 2023 10 20.
Article in English | MEDLINE | ID: mdl-37864255

ABSTRACT

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) comprise a spectrum of neurodegenerative diseases linked to TDP-43 proteinopathy, which at the cellular level, is characterized by loss of nuclear TDP-43 and accumulation of cytoplasmic TDP-43 inclusions that ultimately cause RNA processing defects including dysregulation of splicing, mRNA transport and translation. Complementing our previous work in motor neurons, here we report a novel model of TDP-43 proteinopathy based on overexpression of TDP-43 in a subset of Drosophila Kenyon cells of the mushroom body (MB), a circuit with structural characteristics reminiscent of vertebrate cortical networks. This model recapitulates several aspects of dementia-relevant pathological features including age-dependent neuronal loss, nuclear depletion and cytoplasmic accumulation of TDP-43, and behavioral deficits in working memory and sleep that occur prior to axonal degeneration. RNA immunoprecipitations identify several candidate mRNA targets of TDP-43 in MBs, some of which are unique to the MB circuit and others that are shared with motor neurons. Among the latter is the glypican Dally-like-protein (Dlp), which exhibits significant TDP-43 associated reduction in expression during aging. Using genetic interactions we show that overexpression of Dlp in MBs mitigates TDP-43 dependent working memory deficits, conistent with Dlp acting as a mediator of TDP-43 toxicity. Substantiating our findings in the fly model, we find that the expression of GPC6 mRNA, a human ortholog of dlp, is specifically altered in neurons exhibiting the molecular signature of TDP-43 pathology in FTD patient brains. These findings suggest that circuit-specific Drosophila models provide a platform for uncovering shared or disease-specific molecular mechanisms and vulnerabilities across the spectrum of TDP-43 proteinopathies.


Subject(s)
Amyotrophic Lateral Sclerosis , Frontotemporal Dementia , Pick Disease of the Brain , TDP-43 Proteinopathies , Animals , Humans , Amyotrophic Lateral Sclerosis/pathology , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Drosophila/metabolism , Frontotemporal Dementia/genetics , Frontotemporal Dementia/pathology , Motor Neurons/metabolism , Pick Disease of the Brain/pathology , RNA, Messenger , TDP-43 Proteinopathies/pathology
5.
Sci Rep ; 13(1): 16150, 2023 09 26.
Article in English | MEDLINE | ID: mdl-37752338

ABSTRACT

The Blood-Brain Barrier (BBB) is a highly-selective physiologic barrier responsible for maintaining cerebral homeostasis. Innovative in vitro models of the BBB are needed to provide useful insights into BBB function with CNS disorders like traumatic brain injury (TBI). TBI is a multidimensional and highly complex pathophysiological condition that requires intrinsic models to elucidate its mechanisms. Current models either lack fluidic shear stress, or neglect hemodynamic parameters important in recapitulating the human in vivo BBB phenotype. To address these limitations in the field, we developed a fluid dynamic novel platform which closely mimics these parameters. To validate our platform, Matrigel-coated Transwells were seeded with brain microvascular endothelial cells, both with and without co-cultured primary human astrocytes and bone-marrow mesenchymal stem cells. In this article we characterized BBB functional properties such as TEER and paracellular permeability. Our platform demonstrated physiologic relevant decreases in TEER in response to an ischemic environment, while directly measuring barrier fluid fluctuation. These recordings were followed with recovery, implying stability of the model. We also demonstrate that our dynamic platform is responsive to inflammatory and metabolic cues with resultant permeability coefficients. These results indicate that this novel dynamic platform will be a valuable tool for evaluating the recapitulating BBB function in vitro, screening potential novel therapeutics, and establishing a relevant paradigm to evaluate the pathophysiology of TBI.


Subject(s)
Blood-Brain Barrier , Brain Injuries, Traumatic , Humans , Endothelial Cells , Brain , Astrocytes
6.
J Surg Res ; 291: 646-652, 2023 11.
Article in English | MEDLINE | ID: mdl-37549450

ABSTRACT

INTRODUCTION: A reduction in clot strength is a hallmark feature of trauma-induced coagulopathy. A better understanding of clot integrity can optimize resuscitation strategies. We designed a device to gauge clot strength by pressurizing fluids over a formed clot and measuring the pressure needed to dislodge the clot. We hypothesized that this device could distinguish between clots formed in hypocoagulable and hypercoagulable states by observing differences in the clot burst pressure. METHODS: Whole blood from healthy volunteers was collected into sodium citrate tubes and was treated with heparin or fibrinogen to generate clots in a hypocoagulable or hypercoagulable state, respectively. Small bore holes were drilled into polystyrene plates, and recalcified blood was pipetted into the holes. Plates were incubated at 37°C for 30 min to form clots. A pressure cap with an inlet for fluid from a syringe pump and an outlet leading to a measurement column was secured in the wells with a watertight seal. RESULTS: Clot burst pressure was normalized to individual baseline values to account for inherent differences in clot strength. The 1.0 g/L and 2.0 g/L fibrinogen groups were 1.65 ± 0.07 (P = 0.0078) and 2.26 ± 0.16 (P = 0.0078) times as strong as baseline, respectively. The 0.10, 0.15, or 0.20 USP units/mL groups were 0.388 ± 0.07 (P = 0.125), 0.31 ± 0.07 (P = 0.125), 0.21 ± 0.07 (P = 0.125) times as strong as baseline, respectively. Data were analyzed using Wilcoxon matched pairs signed rank testing. CONCLUSIONS: This device tests clot strength using burst pressure, an easily interpreted clinical parameter not measured in existing devices. Future work can test blood from trauma patients to better understand trauma pathophysiology.


Subject(s)
Blood Coagulation Disorders , Hemostatics , Thrombosis , Humans , Thrombosis/diagnosis , Thrombosis/etiology , Blood Coagulation/physiology , Fibrinogen , Thrombelastography , Resuscitation
7.
J Surg Res ; 291: 43-50, 2023 11.
Article in English | MEDLINE | ID: mdl-37331191

ABSTRACT

INTRODUCTION: Citrate-phosphate-dextrose (CPD) is the most common anticoagulant for blood product storage in the United States. It was developed to prolong shelf life, though there is little research regarding its impact on function following transfusion. We used flow cytometry (FC), thromboelastography (TEG), and a clot contraction assay called the zFlex platform to measure platelet activation and global clot formation in blood samples anticoagulated with either CPD or in a standard blue top citrate (BTC) tube. METHODS: Samples were obtained through venipuncture of the antecubital fossa from healthy donors who had not recently taken antiplatelet medication. Samples for FC analysis were spun to obtain platelet-rich plasma, while TEG and zFlex utilized recalcified whole blood. RESULTS: Mean fluorescence intensity for CD62p (P-selectin, marker of platelet activation) in baseline samples was equal, while mean fluorescence intensity in samples activated with thrombin receptor activating peptide was higher in CPD than BTC (65,814 ± 4445 versus 52,483 ± 5435, P = 0.007). TEG results demonstrated similar maximum amplitude for CPD (62.7 ± 1.8 mm versus 61 ± 1 mm) (P = 0.33), though reaction time and kinetics time were significantly longer in CPD versus BTC. CPD R-time: 7.9 ± 0.4 min versus BTC: 3.8 ± 0.4 (P < 0.001). CPD K-time: 2.2 ± 0.2 min versus BTC: 1.6 ± 0.1 min (P < 0.001). Clot contraction strength was not different between the two groups on zFlex: CPD 4353 ± 6 = 517 µN versus BTC 4901 ± 390 µN (P = 0.39). CONCLUSIONS: Our findings suggest that CPD does not affect platelet function (minimal difference on FC and no difference in ultimate clot strength, which is ∼80% due to platelet function) but may alter clot dynamics by attenuating thrombin generation.


Subject(s)
Blood Coagulation , Thrombosis , Humans , Citrates , Blood Coagulation Tests , Glucose/pharmacology , Thrombelastography , Citric Acid
8.
Crit Care Explor ; 5(6): e0925, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37275654

ABSTRACT

This narrative review article seeks to highlight the effects of citrate on physiology during massive transfusion of the bleeding patient. DATA SOURCES: A limited library of curated articles was created using search terms including "citrate intoxication," "citrate massive transfusion," "citrate pharmacokinetics," "hypocalcemia of trauma," "citrate phosphate dextrose," and "hypocalcemia in massive transfusion." Review articles, as well as prospective and retrospective studies were selected based on their relevance for inclusion in this review. STUDY SELECTION: Given the limited number of relevant studies, studies were reviewed and included if they were written in English. This is not a systematic review nor a meta-analysis. DATA EXTRACTION AND SYNTHESIS: As this is not a meta-analysis, new statistical analyses were not performed. Relevant data were summarized in the body of the text. CONCLUSIONS: The physiologic effects of citrate independent of hypocalcemia are poorly understood. While a healthy individual can rapidly clear the citrate in a unit of blood (either through the citric acid cycle or direct excretion in urine), the physiology of hemorrhagic shock can lead to decreased clearance and prolonged circulation of citrate. The so-called "Diamond of Death" of bleeding-coagulopathy, acidemia, hypothermia, and hypocalcemia-has a dynamic interaction with citrate that can lead to a death spiral. Hypothermia and acidemia both decrease citrate clearance while circulating citrate decreases thrombin generation and platelet function, leading to ionized hypocalcemia, coagulopathy, and need for further transfusion resulting in a new citrate load. Whole blood transfusion typically requires lower volumes of transfused product than component therapy alone, resulting in a lower citrate burden. Efforts should be made to limit the amount of citrate infused into a patient in hemorrhagic shock while simultaneously addressing the induced hypocalcemia.

9.
Nanomedicine (Lond) ; 17(16): 1099-1114, 2022 07.
Article in English | MEDLINE | ID: mdl-36178114

ABSTRACT

Aim: Methotrexate (MTX) is used to treat rheumatoid arthritis (RA) but is associated with severe toxicity. To minimize these side effects of MTX, the study was undertaken to explore its delivery using solid lipid nanoparticles (SLNs). Materials & methods: MTX-loaded SLNs were synthesized and coated with hyaluronic acid (HA) for targeted drug delivery and evaluated for their safety and efficacy in a complete Freund's adjuvant (CFA) model. Results: HA-MTX-SLNs (230.0 ± 46.4 nm) with 78.75% entrapment were developed and showed sustained drug release with a significant reduction in toxicity and enhanced activity of the drug at the targeted site upon oral administration in CFA-induced rats. Conclusion: HA-MTX-SLNs can be considered as an efficient therapeutic agents for the treatment of RA.


Rheumatoid arthritis (RA) is an autoimmune disease of the joints with no cure and treatment modalities only focus on reducing the symptoms. Methotrexate (MTX) is a primary drug used for its treatment but is associated with severe toxicity. The study aimed to use solid lipid nanoparticles (SLNs) as carriers for MTX to achieve improved efficacy in RA treatment at reduced doses, thus decreasing the potential toxicity of the drug, making SLNs suitable and safe drug carriers. MTX-loaded SLNs (MTX-SLNs) were formulated and coated with hyaluronic acid (HA; HA-MTX-SLNs) and were evaluated for their efficacy in a complete Freund's adjuvant (CFA)-induced arthritic rat model. Both MTX-SLNs and HA-MTX-SLNs demonstrated a significant reduction in toxicity and enhanced the activity of the drug upon oral administration. The HA coating further enriched the antirheumatic activity of MTX, owing to its ability to improve the oral bioavailability and targeted drug delivery of the formulation. Thus, HA-MTX-SLNs can be considered efficient therapeutic agents for the treatment of RA.


Subject(s)
Antirheumatic Agents , Arthritis, Experimental , Arthritis, Rheumatoid , Rats , Animals , Methotrexate/pharmacology , Hyaluronic Acid , Freund's Adjuvant/therapeutic use , Arthritis, Experimental/drug therapy , Antirheumatic Agents/pharmacology , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy
10.
Shock ; 58(1): 1-13, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35984758

ABSTRACT

ABSTRACT: Platelets are subcellular anucleate components of blood primarily responsible for initiating and maintaining hemostasis. After injury to a blood vessel, platelets can be activated via several pathways, resulting in changed shape, adherence to the injury site, aggregation to form a plug, degranulation to initiate activation in other nearby platelets, and acceleration of thrombin formation to convert fibrinogen to fibrin before contracting to strengthen the clot. Platelet function assays use agonists to induce and measure one or more of these processes to identify alterations in platelet function that increase the likelihood of bleeding or thrombotic events. In severe trauma, these assays have revealed that platelet dysfunction is strongly associated with poor clinical outcomes. However, to date, the mechanism(s) causing clinically significant platelet dysfunction remain poorly understood. We review the pros, cons, and evidence for use of many of the popular assays in trauma, discuss limitations of their use in this patient population, and present approaches that can be taken to develop improved functional assays capable of elucidating mechanisms of trauma-induced platelet dysfunction. Platelet dysfunction in trauma has been associated with need for transfusions and mortality; however, most of the current platelet function assays were not designed for evaluating trauma patients, and there are limited data regarding their use in this population. New or improved functional assays will help define the mechanisms by which platelet dysfunction occurs, as well as help optimize future treatment.


Subject(s)
Blood Platelets , Hemostasis , Thrombosis , Wounds and Injuries , Blood Platelets/metabolism , Fibrin/metabolism , Hemostasis/physiology , Humans , Platelet Aggregation , Platelet Function Tests/methods , Wounds and Injuries/metabolism
11.
Front Immunol ; 13: 874698, 2022.
Article in English | MEDLINE | ID: mdl-35874742

ABSTRACT

Mesenchymal stromal cells (MSC) undergo functional maturation upon their migration from bone marrow and introduction to a site of injury. This inflammatory licensing leads to heightened immune regulation via cell-to-cell interaction and the secretion of immunomodulatory molecules, such as anti-inflammatory mediators and antioxidants. Pro-inflammatory cytokines are a recognized catalyst of inflammatory licensing; however, biomechanical forces, such as fluid shear stress, are a second, distinct class of stimuli that incite functional maturation. Here we show mechanotransduction, achieved by exposing MSC to various grades of wall shear stress (WSS) within a scalable conditioning platform, enhances the immunomodulatory potential of MSC independent of classical pro-inflammatory cytokines. A dose-dependent effect of WSS on potency is evidenced by production of prostaglandin E2 (PGE2) and indoleamine 2,3 dioxygenase 1 (IDO1), as well as suppression of tumor necrosis factor-α (TNF- α) and interferon-γ (IFN-γ) production by activated immune cells. Consistent, reproducible licensing is demonstrated in adipose tissue and bone marrow human derived MSC without significant impact on cell viability, cellular yield, or identity. Transcriptome analysis of WSS-conditioned BM-MSC elucidates the broader phenotypic implications on the differential expression of immunomodulatory factors. These results suggest mechanotransduction as a viable, scalable pre-conditioning alternative to pro-inflammatory cytokines. Enhancing the immunomodulatory capacity of MSC via biomechanical conditioning represents a novel cell therapy manufacturing approach.


Subject(s)
Mechanotransduction, Cellular , Mesenchymal Stem Cells , Cytokines/metabolism , Dinoprostone/metabolism , Humans , Immunomodulation , Mesenchymal Stem Cells/metabolism
12.
J Ayurveda Integr Med ; 13(1): 100413, 2022.
Article in English | MEDLINE | ID: mdl-33654345

ABSTRACT

BACKGROUND: Outbreak of Corona Virus Disease in late 2019 (COVID-19) has become a pandemic global Public health emergency. Since there is no approved anti-viral drug or vaccine declared for the disease and investigating existing drugs against the COVID-19. OBJECTIVE: AYUSH-64 is an Ayurvedic formulation, developed and patented by Central Council of Research in Ayurvedic Sciences, India, has been in clinical use as anti-malarial, anti-inflammatory, anti-pyretic drug for few decades. Thus, the present study was undertaken to evaluate AYUSH-64 compounds available in this drug against Severe Acute Respiratory Syndrome-Corona Virus (SARS-CoV-2) Main Protease (Mpro; PDB ID: 6LU7) via in silico techniques. MATERIALS AND METHODS: Different molecular docking software's of Discovery studio and Auto Dock Vina were used for drugs from selected AYUSH-64 compounds against SARS-CoV-2. We also conducted 100 ns period of molecular dynamics simulations with Desmond and further MM/GBSA for the best complex of AYUSH-64 with Mpro of SARS-CoV-2. RESULTS: Among 36 compounds of four ingredients of AYUSH-64 screened, 35 observed to exhibits good binding energies than the published positive co-crystal compound of N3 pepetide. The best affinity and interactions of Akuammicine N-Oxide (from Alstonia scholaris) towards the Mpro with binding energy (AutoDock Vina) of -8.4 kcal/mol and Discovery studio of Libdock score of 147.92 kcal/mol. Further, molecular dynamics simulations with MM-GBSA were also performed for Mpro- Akuammicine N-Oxide docked complex to identify the stability, specific interaction between the enzyme and the ligand. Akuammicine N-Oxide is strongly formed h-bonds with crucial Mpro residues, Cys145, and His164. CONCLUSION: The results provide lead that, the presence of Mpro- Akuammicine N-Oxide with highest Mpro binding energy along with other 34 chemical compounds having similar activity as part of AYUSH-64 make it a suitable candidate for repurposing to management of COVID-19 by further validating through experimental, clinical studies.

14.
Int J Mol Sci ; 22(12)2021 Jun 16.
Article in English | MEDLINE | ID: mdl-34208643

ABSTRACT

Myosin Light Chain (MLC) regulates platelet contraction through its phosphorylation by Myosin Light Chain Kinase (MLCK) or dephosphorylation by Myosin Light Chain Phosphatase (MLCP). The correlation between platelet contraction force and levels of MLC phosphorylation is unknown. We investigate the relationship between platelet contraction force and MLC phosphorylation using a novel microelectromechanical (MEMS) based clot contraction sensor (CCS). The MLCK and MLCP pair were interrogated by inhibitors and activators of platelet function. The CCS was fabricated from silicon using photolithography techniques and force was validated over a range of deflection for different chip spring constants. The force of platelet contraction measured by the clot contraction sensor (CCS) was compared to the degree of MLC phosphorylation by Western Blotting (WB) and ELISA. Stimulators of MLC phosphorylation produced higher contraction force, higher phosphorylated MLC signal in ELISA and higher intensity bands in WB. Inhibitors of MLC phosphorylation produced the opposite. Contraction force is linearly related to levels of phosphorylated MLC. Direct measurements of clot contractile force are possible using a MEMS sensor platform and correlate linearly with the degree of MLC phosphorylation during coagulation. Measured force represents the mechanical output of the actin/myosin motor in platelets regulated by myosin light chain phosphorylation.


Subject(s)
Blood Platelets/physiology , Micro-Electrical-Mechanical Systems/methods , Platelet Function Tests/methods , Algorithms , Biosensing Techniques , Blood Platelets/ultrastructure , Enzyme-Linked Immunosorbent Assay , Micro-Electrical-Mechanical Systems/instrumentation , Models, Theoretical , Myosin Light Chains/metabolism , Phosphorylation , Platelet Function Tests/instrumentation
15.
Blood ; 138(12): 1053-1066, 2021 09 23.
Article in English | MEDLINE | ID: mdl-33900379

ABSTRACT

B-cell receptor (BCR) signals play a critical role in the pathogenesis of chronic lymphocytic leukemia (CLL), but their role in regulating CLL cell proliferation has still not been firmly established. Unlike normal B cells, CLL cells do not proliferate in vitro upon engagement of the BCR, suggesting that CLL cell proliferation is regulated by other signals from the microenvironment, such as those provided by Toll-like receptors or T cells. Here, we report that BCR engagement of human and murine CLL cells induces several positive regulators of the cell cycle, but simultaneously induces the negative regulators CDKN1A, CDKN2A, and CDKN2B, which block cell-cycle progression. We further show that introduction of genetic lesions that downregulate these cell-cycle inhibitors, such as inactivating lesions in CDKN2A, CDKN2B, and the CDKN1A regulator TP53, leads to more aggressive disease in a murine in vivo CLL model and spontaneous proliferation in vitro that is BCR dependent but independent of costimulatory signals. Importantly, inactivating lesions in CDKN2A, CDKN2B, and TP53 frequently co-occur in Richter syndrome (RS), and BCR stimulation of human RS cells with such lesions is sufficient to induce proliferation. We also show that tumor cells with combined TP53 and CDKN2A/2B abnormalities remain sensitive to BCR-inhibitor treatment and are synergistically sensitive to the combination of a BCR and cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor both in vitro and in vivo. These data provide evidence that BCR signals are directly involved in driving CLL cell proliferation and reveal a novel mechanism of Richter transformation.


Subject(s)
Cell Transformation, Neoplastic , Cyclin-Dependent Kinase Inhibitor p15 , Cyclin-Dependent Kinase Inhibitor p16 , Leukemia, Lymphocytic, Chronic, B-Cell , Receptors, Antigen, B-Cell , Signal Transduction , Tumor Suppressor Protein p53 , Animals , Cell Line, Tumor , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/immunology , Cyclin-Dependent Kinase Inhibitor p15/genetics , Cyclin-Dependent Kinase Inhibitor p15/immunology , Cyclin-Dependent Kinase Inhibitor p16/genetics , Cyclin-Dependent Kinase Inhibitor p16/immunology , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/immunology , Mice , Receptors, Antigen, B-Cell/genetics , Receptors, Antigen, B-Cell/immunology , Signal Transduction/genetics , Signal Transduction/immunology , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/immunology
16.
Sci Rep ; 10(1): 22211, 2020 12 17.
Article in English | MEDLINE | ID: mdl-33335275

ABSTRACT

The only available option to treat radiation-induced hematopoietic syndrome is allogeneic hematopoietic cell transplantation, a therapy unavailable to many patients undergoing treatment for malignancy, which would also be infeasible in a radiological disaster. Stromal cells serve as critical components of the hematopoietic stem cell niche and are thought to protect hematopoietic cells under stress. Prior studies that have transplanted mesenchymal stromal cells (MSCs) without co-administration of a hematopoietic graft have shown underwhelming rescue of endogenous hematopoiesis and have delivered the cells within 24 h of radiation exposure. Herein, we examine the efficacy of a human bone marrow-derived MSC therapy delivered at 3 h or 30 h in ameliorating radiation-induced hematopoietic syndrome and show that pancytopenia persists despite MSC therapy. Animals exposed to radiation had poorer survival and experienced loss of leukocytes, platelets, and red blood cells. Importantly, mice that received a therapeutic dose of MSCs were significantly less likely to die but experienced equivalent collapse of the hematopoietic system. The cause of the improved survival was unclear, as complete blood counts, splenic and marrow cellularity, numbers and function of hematopoietic stem and progenitor cells, and frequency of niche cells were not significantly improved by MSC therapy. Moreover, human MSCs were not detected in the bone marrow. MSC therapy reduced crypt dropout in the small intestine and promoted elevated expression of growth factors with established roles in gut development and regeneration, including PDGF-A, IGFBP-3, IGFBP-2, and IGF-1. We conclude that MSC therapy improves survival not through overt hematopoietic rescue but by positive impact on other radiosensitive tissues, such as the intestinal mucosa. Collectively, these data reveal that MSCs could be an effective countermeasure in cancer patients and victims of nuclear accidents but that MSCs alone do not significantly accelerate or contribute to recovery of the blood system.


Subject(s)
Hematopoiesis/radiation effects , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/metabolism , Radiation Injuries/mortality , Radiation Injuries/therapy , Animals , Biopsy , Bone Marrow/metabolism , Bone Marrow/pathology , Bone Marrow/radiation effects , Bone Marrow Cells/metabolism , Bone Marrow Cells/radiation effects , Disease Models, Animal , Female , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Hematopoietic Stem Cells/radiation effects , Humans , Immunophenotyping , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Intestinal Mucosa/radiation effects , Male , Mesenchymal Stem Cells/cytology , Pancytopenia/etiology , Pancytopenia/metabolism , Pancytopenia/pathology , Prognosis , Radiation Injuries/pathology , Radiotherapy/adverse effects , Treatment Outcome
17.
Sci Rep ; 10(1): 10729, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32612177

ABSTRACT

The immune system plays critical roles in promoting tissue repair during recovery from neurotrauma but is also responsible for unchecked inflammation that causes neuronal cell death, systemic stress, and lethal immunodepression. Understanding the immune response to neurotrauma is an urgent priority, yet current models of traumatic brain injury (TBI) inadequately recapitulate the human immune response. Here, we report the first description of a humanized model of TBI and show that TBI places significant stress on the bone marrow. Hematopoietic cells of the marrow are regionally decimated, with evidence pointing to exacerbation of underlying graft-versus-host disease (GVHD) linked to presence of human T cells in the marrow. Despite complexities of the humanized mouse, marrow aplasia caused by TBI could be alleviated by cell therapy with human bone marrow mesenchymal stromal cells (MSCs). We conclude that MSCs could be used to ameliorate syndromes triggered by hypercytokinemia in settings of secondary inflammatory stimulus that upset marrow homeostasis such as TBI. More broadly, this study highlights the importance of understanding how underlying immune disorders including immunodepression, autoimmunity, and GVHD might be intensified by injury.


Subject(s)
Brain Injuries, Traumatic/physiopathology , Graft vs Host Disease/etiology , Immune Tolerance/immunology , Mesenchymal Stem Cells/cytology , T-Lymphocytes/immunology , Animals , Female , Graft vs Host Disease/pathology , Graft vs Host Disease/therapy , Male , Mesenchymal Stem Cell Transplantation , Mice , Mice, Inbred NOD , Mice, SCID
18.
Curr Drug Targets ; 21(8): 736-775, 2020.
Article in English | MEDLINE | ID: mdl-31995004

ABSTRACT

Long before the discovery of drugs like 'antibiotic and anti-parasitic drugs', the infectious diseases caused by pathogenic bacteria and parasites remain as one of the major causes of morbidity and mortality in developing and underdeveloped countries. The phenomenon by which the organism exerts resistance against two or more structurally unrelated drugs is called multidrug resistance (MDR) and its emergence has further complicated the treatment scenario of infectious diseases. Resistance towards the available set of treatment options and poor pipeline of novel drug development puts an alarming situation. A universal goal in the post-genomic era is to identify novel targets/drugs for various life-threatening diseases caused by such pathogens. This review is conceptualized in the backdrop of drug resistance in two major pathogens i.e. "Pseudomonas aeruginosa" and "Plasmodium falciparum". In this review, the available targets and key mechanisms of resistance of these pathogens have been discussed in detail. An attempt has also been made to analyze the common drug targets of bacteria and malaria parasite to overcome the current drug resistance scenario. The solution is also hypothesized in terms of a present pipeline of drugs and efforts made by scientific community.


Subject(s)
Bacteria/drug effects , Malaria/drug therapy , Anti-Bacterial Agents/pharmacology , Antimalarials/pharmacology , Drug Resistance, Multiple , Humans , Plasmodium falciparum/chemistry , Plasmodium falciparum/cytology , Plasmodium falciparum/drug effects , Plasmodium falciparum/pathogenicity , Pseudomonas aeruginosa/chemistry , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/pathogenicity
19.
Stem Cells Transl Med ; 9(4): 491-498, 2020 04.
Article in English | MEDLINE | ID: mdl-31903737

ABSTRACT

Clinical trials in trauma populations are exploring the use of clinical cellular therapeutics (CCTs) like human mesenchymal stromal cells (MSC) and mononuclear cells (MNC). Recent studies demonstrate a procoagulant effect of these CCTs related to their expression of tissue factor (TF). We sought to examine this relationship in blood from severely injured trauma patients and identify methods to reverse this procoagulant effect. Human MSCs from bone marrow, adipose, and amniotic tissues and freshly isolated bone marrow MNC samples were tested. TF expression and phenotype were quantified using flow cytometry. CCTs were mixed individually with trauma patients' whole blood, assayed with thromboelastography (TEG), and compared with healthy subjects mixed with the same cell sources. Heparin was added to samples at increasing concentrations until TEG parameters normalized. Clotting time or R time in TEG decreased relative to the TF expression of the CCT treatment in a logarithmic fashion for trauma patients and healthy subjects. Nonlinear regression curves were significantly different with healthy subjects demonstrating greater relative decreases in TEG clotting time. In vitro coadministration of heparin normalized the procoagulant effect and required dose escalation based on TF expression. TF expression in human MSC and MNC has a procoagulant effect in blood from trauma patients and healthy subjects. The procoagulant effect is lower in trauma patients possibly because their clotting time is already accelerated. The procoagulant effect due to MSC/MNC TF expression could be useful in the bleeding trauma patient; however, it may emerge as a safety release criterion due to thrombotic risk. The TF procoagulant effect is reversible with heparin.


Subject(s)
Blood Coagulation , Wounds and Injuries/blood , Adult , Biomarkers/metabolism , Blood Coagulation/drug effects , Case-Control Studies , Female , Heparin/pharmacology , Humans , Male , Thrombelastography
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