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1.
J Clin Pharm Ther ; 47(12): 2107-2114, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36543256

ABSTRACT

WHAT IS KNOWN AND OBJECTIVE: Unintentional medication discrepancies (UMDs) are common in geriatric patients during care transitions, resulting in frequent undesirable consequences. Medication reconciliation could be a useful practice to prevent or ameliorate UMD. However, this practice in Vietnamese hospitals has not been well established or standardized. This study aims to determine the effect of pharmacist-initiated educational interventions on improving medication reconciliation practice. METHODS: This prospective 6-month pre-and post-study was conducted in two internal medicine wards in a Vietnamese 800-bed public hospital. Pharmacists provided training and short-term support to physicians on medication reconciliation. Primary outcome measures were the proportions of patients with at least one UMD at admission. Secondary outcome measures were the proportions of patients with preventable adverse drug events (pADEs) score ≥0.1 due to these UMDs. Odds ratio and 95% confidence intervals were assessed based on a multivariate logistic regression model. RESULTS AND DISCUSSION: One hundred fifty-two patients were recruited in the pre-intervention phase, and 146 in the post-intervention phase. Following the intervention, the proportion of geriatric patients with ≥1 UMD at admission significantly decreased from 55.3 to 25.3 % (ORadj 0.255, 95% CI: 0.151-0.431). Similarly, the proportion of patients with a pADE ≥0.1 at admission reduced from 44.1 to 11.6% [ORadj 0.188, 95% CI: 0.105-0.340] post-intervention. WHAT IS NEW AND CONCLUSION: Our pharmacist-initiated educational interventions have demonstrated the ability to produce substantial improvement in medication reconciliation practice, reducing UMDs and potential harm. Our approach may provide an alternate option to implement medication reconciliation for jurisdictions with limited healthcare resources.


Subject(s)
Medication Reconciliation , Pharmacy Service, Hospital , Humans , Aged , Pharmacists , Medication Errors/prevention & control , Prospective Studies , Inpatients , Vietnam , Hospitals , Pharmacy Service, Hospital/methods , Patient Admission
2.
BMC Health Serv Res ; 22(1): 878, 2022 Jul 07.
Article in English | MEDLINE | ID: mdl-35799184

ABSTRACT

BACKGROUND: Clinical pharmacy activities have evolved over the past decades contributing to all stages of the patient care process, especially in the hospital setting. However, these practice roles may differ to a significant extent depending on the healthcare policy of countries. In Vietnam, the magnitude of adopting clinical pharmacy activities in hospital settings throughout the country is still unknown since these activities have been implemented. This study aimed to ascertain the current status of clinical pharmacy activities performed within the Vietnamese hospital setting. METHODS: A nation-wide survey was conducted from December 2017 to January 2018. Two online questionnaires, one for the Heads of Pharmacy Department and one for clinical pharmacists, were designed based on the national legal regulations about implementing clinical pharmacy activities in the hospital setting. These questionnaires were sent to all hospitals and healthcare facilities with a department of pharmacy. RESULTS: A total of 560 Heads of Pharmacy and 574 clinical pharmacists participated in the study, representing a response rate of 41.2%. Among the participating hospitals, non-patient specific activities were implemented widely across all hospital classes, with pharmacovigilance, medication information, and standard operating procedures development implemented in ≥88% of all hospitals. In contrast, there was a significant variation in the level of implementation of patient-specific activities among hospital classes. With activities such as medication counselling, monitoring of adverse drug reactions, and obtaining patient's medication histories provided at a considerably lower level in between 49 and 57% of hospitals. CONCLUSION: Clinical pharmacy activities have been initiated in most of the surveyed hospitals. In general, clinical pharmacy is more established in higher-class hospitals in Vietnam. However, the current implementation status is focused on non-patient-specific activities, while patient-oriented activities remained insufficiently established.


Subject(s)
Pharmacy Service, Hospital , Pharmacy , Hospitals , Humans , Pharmacists , Surveys and Questionnaires , Vietnam
3.
J Cell Sci ; 132(11)2019 06 12.
Article in English | MEDLINE | ID: mdl-31076516

ABSTRACT

The cell nucleus responds to mechanical cues with changes in size, morphology and motility. Previous work has shown that external forces couple to nuclei through the cytoskeleton network, but we show here that changes in nuclear shape can be driven solely by calcium levels. Fluid shear stress applied to MDCK cells caused the nuclei to shrink through a Ca2+-dependent signaling pathway. Inhibiting mechanosensitive Piezo1 channels through treatment with GsMTx4 prevented nuclear shrinkage. Piezo1 knockdown also significantly reduced the nuclear shrinkage. Activation of Piezo1 with the agonist Yoda1 caused similar nucleus shrinkage in cells not exposed to shear stress. These results demonstrate that the Piezo1 channel is a key element for transmitting shear force input to nuclei. To ascertain the relative contribution of Ca2+ to cytoskeleton perturbation, we examined F-actin reorganization under shear stress and static conditions, and showed that reorganization of the cytoskeleton is not necessary for nuclear shrinkage. These results emphasize the role of the mechanosensitive channels as primary transducers in force transmission to the nucleus.


Subject(s)
Calcium/metabolism , Cell Nucleus Shape/physiology , Epithelial Cells/metabolism , Ion Channels/metabolism , Mechanotransduction, Cellular/physiology , Stress, Mechanical , Animals , Calcium Signaling/physiology , Cell Line , Cell Nucleus/physiology , Cytoskeleton/physiology , Dogs , Madin Darby Canine Kidney Cells
4.
J Liposome Res ; 29(4): 357-367, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30526169

ABSTRACT

Targeted delivery of therapeutics to the uterus is an important goal in the treatment of obstetric complications, such as preterm labour, postpartum hemorrhage, and dysfunctional labour. Current treatment for these obstetric complications is challenging, as there are limited effective and safe therapeutic options available. We have developed a targeted drug delivery system for the uterus by conjugating anti-oxytocin receptor (OTR) antibodies to the surface of PEGylated liposomes (OTR-PEG-ILs). The functionality of the OTR-PEG-ILs has previously been evaluated on human and murine myometrial tissues as well as in vivo in a murine model of preterm labour. The aim of this study was to report the pharmaceutical synthesis and characterization of the OTR-PEG-ILs and investigate their specific cellular interaction with OTR-expressing myometrial cells in vitro. Immunoliposomes composed of 1,2-distearoyl-sn-glycero-2-phosphocholine (DSPC) and cholesterol were prepared using an optimized method for the coupling of low concentrations of antibody to liposomes. The liposomes were characterized for particle size, antibody conjugation, drug encapsulation, liposome stability, specificity of binding, cellular internalization, mechanistic pathway of cellular uptake, and cellular toxicity. Cellular association studies demonstrated specific binding of OTR-PEG-ILs to OTRs and significant cellular uptake following binding. Evaluation of the mechanistic pathway of cellular uptake indicated that they undergo internalization through both clathrin- and caveolin-mediated mechanisms. Furthermore, cellular toxicity studies have shown no significant effect of OTR-PEG-ILs or the endocytotic inhibitors on cell viability. This study further supports oxytocin receptors as a novel pharmaceutical target for drug delivery to the uterus.


Subject(s)
Delayed-Action Preparations/chemistry , Liposomes/chemistry , Nanocapsules/chemistry , Receptors, Oxytocin/immunology , Uterus/metabolism , Animals , Antibodies/chemistry , Antibodies/immunology , Biological Transport , Cell Line , Cell Survival/drug effects , Cholesterol/chemistry , Drug Compounding/methods , Drug Stability , Female , Humans , Mice , Myometrium/cytology , Phosphatidylcholines/chemistry , Polyethylene Glycols/chemistry , Signal Transduction , Surface Properties
5.
Exp Cell Res ; 359(2): 327-336, 2017 10 15.
Article in English | MEDLINE | ID: mdl-28803065

ABSTRACT

Adherens junctions (AJs) are a key structural component for tissue organization and function. Under fluid shear stress, AJs exhibit dynamic assembly/disassembly, but how shear stress couples to AJs is unclear. In MDCK cells we measured simultaneously the forces in cytoskeletal α-actinin and the density and length of AJs using a genetically coded optical force sensor, actinin-sstFRET, and fluorescently labeled E-cadherin (E-cad). We found that shear stress of 0.74dyn/cm2 for 3h significantly enhanced E-cad expression at cell-cell contacts and this phenomenon has two phases. The initial formation of segregated AJ plaques coincided with a decrease in cytoskeletal tension, but an increase in tension was necessary for expansion of the plaques and the formation of continuous AJs in the later phase. The changes in cytoskeletal tension and reorganization appear to be an upstream process in response to flow since it occurred in both wild type and dominant negative E-cad cells. Disruption of F-actin with a Rho-ROCK inhibitor eliminated AJ growth under flow. These results delineate the shear stress transduction paths in cultured cells, which helps to understand pathology of a range of diseases that involve dysfunction of E-cadherin.


Subject(s)
Actin Cytoskeleton/metabolism , Adherens Junctions/metabolism , Mechanotransduction, Cellular , Stress, Mechanical , Actin Cytoskeleton/ultrastructure , Actinin/genetics , Actinin/metabolism , Actins/genetics , Actins/metabolism , Adherens Junctions/ultrastructure , Amides/pharmacology , Animals , Biomechanical Phenomena , Biosensing Techniques , Cadherins/genetics , Cadherins/metabolism , Dogs , Fluorescence Resonance Energy Transfer , Gene Expression Regulation , Madin Darby Canine Kidney Cells , Protein Kinase Inhibitors/pharmacology , Pyridines/pharmacology , Rheology , rho-Associated Kinases/antagonists & inhibitors , rho-Associated Kinases/genetics , rho-Associated Kinases/metabolism
6.
Am J Obstet Gynecol ; 216(3): 283.e1-283.e14, 2017 03.
Article in English | MEDLINE | ID: mdl-27567564

ABSTRACT

BACKGROUND: The ability to provide safe and effective pharmacotherapy during obstetric complications, such as preterm labor or postpartum hemorrhage, is hampered by the systemic toxicity of therapeutic agents leading to adverse side effects in the mother and fetus. Development of novel strategies to target tocolytic and uterotonic agents specifically to uterine myocytes would improve therapeutic efficacy while minimizing the risk of side effects. Ligand-targeted liposomes have emerged as a reliable and versatile platform for targeted drug delivery to specific cell types, tissues or organs. OBJECTIVE: Our objective was to develop a targeted drug delivery system for the uterus utilizing an immunoliposome platform targeting the oxytocin receptor. STUDY DESIGN: We conjugated liposomes to an antibody that recognizes an extracellular domain of the oxytocin receptor. We then examined the ability of oxytocin receptor-targeted liposomes to deliver contraction-blocking (nifedipine, salbutamol and rolipram) or contraction-enhancing (dofetilide) agents to strips of spontaneously contracting myometrial tissue in vitro (human and mouse). We evaluated the ability of oxytocin receptor-targeted liposomes to localize to uterine tissue in vivo, and assessed if targeted liposomes loaded with indomethacin were capable of preventing lipopolysaccharide-induced preterm birth in mice. RESULTS: Oxytocin receptor-targeted liposomes loaded with nifedipine, salbutamol or rolipram consistently abolished human myometrial contractions in vitro, while oxytocin receptor-targeted liposomes loaded with dofetilide increased contraction duration. Nontargeted control liposomes loaded with these agents had no effect. Similar results were observed in mouse uterine strips. Following in vivo administration to pregnant mice, oxytocin receptor-targeted liposomes localized specifically to the uterine horns and mammary tissue. Targeting increased localization to the uterus 7-fold. Localization was not detected in the maternal brain or fetus. Targeted and nontargeted liposomes also localized to the liver. Oxytocin receptor-targeted liposomes loaded with indomethacin were effective in reducing rates of preterm birth in mice, whereas nontargeted liposomes loaded with indomethacin had no effect. CONCLUSION: Our results demonstrate that oxytocin receptor-targeted liposomes can be used to either inhibit or enhance human uterine contractions in vitro. In vivo, the liposomes localized to the uterine tissue of pregnant mice and were effective in delivering agents for the prevention of inflammation-induced preterm labor. The potential clinical advantage of targeted liposomal drug delivery to the myometrium is reduced dose and reduced toxicity to both mother and fetus.


Subject(s)
Premature Birth/prevention & control , Receptors, Oxytocin/drug effects , Uterine Contraction/drug effects , Uterus/drug effects , Albuterol/administration & dosage , Albuterol/pharmacokinetics , Animals , Drug Delivery Systems , Female , Indomethacin/administration & dosage , Liposomes/immunology , Mice , Myometrium/drug effects , Myometrium/metabolism , Nifedipine/administration & dosage , Nifedipine/pharmacokinetics , Phenethylamines/administration & dosage , Phenethylamines/pharmacokinetics , Pregnancy , Rolipram/administration & dosage , Rolipram/pharmacokinetics , Sulfonamides/administration & dosage , Sulfonamides/pharmacokinetics , Tissue Distribution , Uterine Contraction/immunology , Uterus/immunology
7.
Nucleic Acids Res ; 42(Database issue): D26-31, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24225321

ABSTRACT

The U.S. Department of Energy (DOE) Joint Genome Institute (JGI), a national user facility, serves the diverse scientific community by providing integrated high-throughput sequencing and computational analysis to enable system-based scientific approaches in support of DOE missions related to clean energy generation and environmental characterization. The JGI Genome Portal (http://genome.jgi.doe.gov) provides unified access to all JGI genomic databases and analytical tools. The JGI maintains extensive data management systems and specialized analytical capabilities to manage and interpret complex genomic data. A user can search, download and explore multiple data sets available for all DOE JGI sequencing projects including their status, assemblies and annotations of sequenced genomes. Here we describe major updates of the Genome Portal in the past 2 years with a specific emphasis on efficient handling of the rapidly growing amount of diverse genomic data accumulated in JGI.


Subject(s)
Databases, Nucleic Acid , Genomics , Genome , High-Throughput Nucleotide Sequencing , Internet , Sequence Analysis, DNA , Systems Integration
8.
Exp Cell Res ; 327(1): 57-67, 2014 Sep 10.
Article in English | MEDLINE | ID: mdl-25088253

ABSTRACT

Adherent cells interact with extracellular matrix via cell-substrate contacts at focal adhesions. The dynamic assembly and disassembly of focal adhesions enables cell attachment, migration and growth. While the influence of mechanical forces on the formation and growth of focal adhesions has been widely observed, the force loading on specific proteins at focal adhesion complex is not clear. By co-expressing force sensitive α-actinin FRET probes and fluorescence labeled paxillin in MDCK cells, we have simultaneously observed the time-dependent changes in tension in α-actinin and the dynamics of focal adhesion during cell migration. We show that increase in tension in α-actinin at the focal adhesion coincides with elongation of the adhesion in its growth phase. The enlargement of focal adhesion is through a force sensitive recruitment of α-actinin and paxillin to the adhesion sites. Changes in α-actinin tension and correlated relocation of α-actinin in an active adhesion also guide the growth direction of the adhesion. The results support the model that cytoskeletal tension is coupled to focal adhesion via the linking protein, α-actinin at the adhesion complex. Lysophosphatidic acid caused an immediate increase in α-actinin tension followed by drastic focal adhesion formation and elongation. Application of Rho-ROCK inhibitor, Y27632, resulted in reversible reduction in tension in α-actinin and disassociation of focal adhesion, suggesting the involvement of myosin-II mediated contractile force in the focal adhesion dynamics. These findings suggest that α-actinin not only serves as a physical linker between cytoskeleton and integrin, but also participates in force transmission at adhesion sites to facilitate adhesion׳s growth.


Subject(s)
Actins/metabolism , Focal Adhesions/metabolism , Animals , Cell Line , Cell Movement/physiology , Cytoskeleton/metabolism , Dogs , Integrins/metabolism , Madin Darby Canine Kidney Cells , Myosin Type II/metabolism , Paxillin/metabolism
9.
Nanomedicine ; 11(5): 1117-32, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25784453

ABSTRACT

Colon targeted drug delivery is an active area of research for local diseases affecting the colon, as it improves the efficacy of therapeutics and enables localized treatment, which reduces systemic toxicity. Targeted delivery of therapeutics to the colon is particularly advantageous for the treatment of inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn's disease. Advances in oral drug delivery design have significantly improved the bioavailability of drugs to the colon; however in order for a drug to have therapeutic efficacy during disease, considerations must be made for the altered physiology of the gastrointestinal (GI) tract that is associated with GI inflammation. Nanotechnology has been used in oral dosage formulation design as strategies to further enhance uptake into diseased tissue within the colon. This review will describe some of the physiological challenges faced by orally administered delivery systems in IBD, the important developments in orally administered nano-delivery systems for colon targeting, and the future advances of this research. FROM THE CLINICAL EDITOR: Inflammatory Bowel Disease (IBD) poses a significant problem for a large number of patients worldwide. Current medical therapy mostly aims at suppressing the active inflammatory episodes. In this review article, the authors described and discussed the various approaches current nano-delivery systems can offer in overcoming the limitations of conventional drug formulations.


Subject(s)
Colon/drug effects , Drug Carriers/chemistry , Drug Delivery Systems/methods , Inflammatory Bowel Diseases/drug therapy , Nanostructures/chemistry , Pharmaceutical Preparations/administration & dosage , Administration, Oral , Animals , Colon/metabolism , Colon/pathology , Drug Carriers/metabolism , Humans , Inflammatory Bowel Diseases/metabolism , Inflammatory Bowel Diseases/pathology
10.
Glia ; 62(4): 608-22, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24482245

ABSTRACT

Network activity in the brain is associated with a transient increase in extracellular K(+) concentration. The excess K(+) is removed from the extracellular space by mechanisms proposed to involve Kir4.1-mediated spatial buffering, the Na(+)/K(+)/2Cl(-) cotransporter 1 (NKCC1), and/or Na(+)/K(+)-ATPase activity. Their individual contribution to [K(+)]o management has been of extended controversy. This study aimed, by several complementary approaches, to delineate the transport characteristics of Kir4.1, NKCC1, and Na(+)/K(+)-ATPase and to resolve their involvement in clearance of extracellular K(+) transients. Primary cultures of rat astrocytes displayed robust NKCC1 activity with [K(+)]o increases above basal levels. Increased [K(+)]o produced NKCC1-mediated swelling of cultured astrocytes and NKCC1 could thereby potentially act as a mechanism of K(+) clearance while concomitantly mediate the associated shrinkage of the extracellular space. In rat hippocampal slices, inhibition of NKCC1 failed to affect the rate of K(+) removal from the extracellular space while Kir4.1 enacted its spatial buffering only during a local [K(+)]o increase. In contrast, inhibition of the different isoforms of Na(+)/K(+)-ATPase reduced post-stimulus clearance of K(+) transients. The astrocyte-characteristic α2ß2 subunit composition of Na(+)/K(+)-ATPase, when expressed in Xenopus oocytes, displayed a K(+) affinity and voltage-sensitivity that would render this subunit composition specifically geared for controlling [K(+)]o during neuronal activity. In rat hippocampal slices, simultaneous measurements of the extracellular space volume revealed that neither Kir4.1, NKCC1, nor Na(+)/K(+)-ATPase accounted for the stimulus-induced shrinkage of the extracellular space. Thus, NKCC1 plays no role in activity-induced extracellular K(+) recovery in native hippocampal tissue while Kir4.1 and Na(+)/K(+)-ATPase serve temporally distinct roles.


Subject(s)
Hippocampus/metabolism , Potassium Channels, Inwardly Rectifying/metabolism , Potassium/metabolism , Sodium-Potassium-Exchanging ATPase/metabolism , Solute Carrier Family 12, Member 2/metabolism , Animals , Animals, Newborn , Bumetanide/pharmacology , Cells, Cultured , Cerebral Cortex/cytology , Cerebral Cortex/drug effects , Dose-Response Relationship, Drug , Excitatory Amino Acid Agonists/pharmacology , Extracellular Fluid/metabolism , Hippocampus/cytology , Hippocampus/drug effects , In Vitro Techniques , Male , Membrane Potentials/drug effects , Membrane Potentials/physiology , Oocytes , Potassium/pharmacology , Rats , Rats, Sprague-Dawley , Sodium Potassium Chloride Symporter Inhibitors/pharmacology , Xenopus laevis
11.
J Control Release ; 370: 835-865, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38744345

ABSTRACT

Diffuse midline glioma (DMG), including tumors diagnosed in the brainstem (diffuse intrinsic pontine glioma - DIPG), is the primary cause of brain tumor-related death in pediatric patients. DIPG is characterized by a median survival of <12 months from diagnosis, harboring the worst 5-year survival rate of any cancer. Corticosteroids and radiation are the mainstay of therapy; however, they only provide transient relief from the devastating neurological symptoms. Numerous therapies have been investigated for DIPG, but the majority have been unsuccessful in demonstrating a survival benefit beyond radiation alone. Although many barriers hinder brain drug delivery in DIPG, one of the most significant challenges is the blood-brain barrier (BBB). Therapeutic compounds must possess specific properties to enable efficient passage across the BBB. In brain cancer, the BBB is referred to as the blood-brain tumor barrier (BBTB), where tumors disrupt the structure and function of the BBB, which may provide opportunities for drug delivery. However, the biological characteristics of the brainstem's BBB/BBTB, both under normal physiological conditions and in response to DIPG, are poorly understood, which further complicates treatment. Better characterization of the changes that occur in the BBB/BBTB of DIPG patients is essential, as this informs future treatment strategies. Many novel drug delivery technologies have been investigated to bypass or disrupt the BBB/BBTB, including convection enhanced delivery, focused ultrasound, nanoparticle-mediated delivery, and intranasal delivery, all of which are yet to be clinically established for the treatment of DIPG. Herein, we review what is known about the BBB/BBTB and discuss the current status, limitations, and advances of conventional and novel treatments to improving brain drug delivery in DIPG.


Subject(s)
Antineoplastic Agents , Blood-Brain Barrier , Brain Stem Neoplasms , Diffuse Intrinsic Pontine Glioma , Drug Delivery Systems , Humans , Brain Stem Neoplasms/drug therapy , Animals , Diffuse Intrinsic Pontine Glioma/drug therapy , Drug Delivery Systems/methods , Blood-Brain Barrier/metabolism , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/pharmacokinetics , Glioma/drug therapy
12.
J Clin Invest ; 134(6)2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38319732

ABSTRACT

Diffuse midline glioma (DMG), including tumors diagnosed in the brainstem (diffuse intrinsic pontine glioma; DIPG), are uniformly fatal brain tumors that lack effective treatment. Analysis of CRISPR/Cas9 loss-of-function gene deletion screens identified PIK3CA and MTOR as targetable molecular dependencies across patient derived models of DIPG, highlighting the therapeutic potential of the blood-brain barrier-penetrant PI3K/Akt/mTOR inhibitor, paxalisib. At the human-equivalent maximum tolerated dose, mice treated with paxalisib experienced systemic glucose feedback and increased insulin levels commensurate with patients using PI3K inhibitors. To exploit genetic dependence and overcome resistance while maintaining compliance and therapeutic benefit, we combined paxalisib with the antihyperglycemic drug metformin. Metformin restored glucose homeostasis and decreased phosphorylation of the insulin receptor in vivo, a common mechanism of PI3K-inhibitor resistance, extending survival of orthotopic models. DIPG models treated with paxalisib increased calcium-activated PKC signaling. The brain penetrant PKC inhibitor enzastaurin, in combination with paxalisib, synergistically extended the survival of multiple orthotopic patient-derived and immunocompetent syngeneic allograft models; benefits potentiated in combination with metformin and standard-of-care radiotherapy. Therapeutic adaptation was assessed using spatial transcriptomics and ATAC-Seq, identifying changes in myelination and tumor immune microenvironment crosstalk. Collectively, this study has identified what we believe to be a clinically relevant DIPG therapeutic combinational strategy.


Subject(s)
Brain Stem Neoplasms , Diffuse Intrinsic Pontine Glioma , Glioma , Metformin , Humans , Mice , Animals , Diffuse Intrinsic Pontine Glioma/drug therapy , Diffuse Intrinsic Pontine Glioma/genetics , Phosphatidylinositol 3-Kinases/genetics , Brain Stem Neoplasms/drug therapy , Brain Stem Neoplasms/genetics , Glioma/drug therapy , Glioma/genetics , Glioma/pathology , TOR Serine-Threonine Kinases/genetics , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Phosphoinositide-3 Kinase Inhibitors/therapeutic use , Glucose , Metformin/pharmacology , Tumor Microenvironment
13.
Glia ; 61(7): 1101-12, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23616425

ABSTRACT

Aquaporin 4 (AQP4) is the predominant water channel in the mammalian brain and is mainly expressed in the perivascular glial endfeet at the brain-blood interface. AQP4 has been described as an important entry and exit site for water during formation of brain edema and regulation of AQP4 is therefore of therapeutic interest. Phosphorylation of some aquaporins has been proposed to regulate their water permeability via gating of the channel itself. Protein kinase (PK)-dependent phosphorylation of Ser(111) has been reported to increase the water permeability of AQP4 expressed in an astrocytic cell line. This possibility was, however, questioned based on the crystal structure of the human AQP4. Our study aimed to resolve if Ser(111) was indeed a site involved in phosphorylation-mediated gating of AQP4. The water permeability of AQP4-expressing Xenopus oocytes was not altered by a range of activators and inhibitors of PKG and PKA. Mutation of Ser(111) to alanine or aspartate (to prevent or mimic phosphorylation) did not change the water permeability of AQP4. PKG activation had no effect on the water permeability of AQP4 in primary cultures of rat astrocytes. Molecular dynamics simulations of a phosphorylation of AQP4.Ser(111) recorded no phosphorylation-induced change in water permeability. A phospho-specific antibody, exclusively recognizing AQP4 when phosphorylated on Ser(111) , failed to detect phosphorylation in cell lysate of rat brain stimulated by conditions proposed to induce phosphorylation of this residue. Thus, our data indicate a lack of phosphorylation of Ser(111) and of phosphorylation-dependent gating of AQP4.


Subject(s)
Aquaporin 4/metabolism , Ion Channel Gating/physiology , Serine/metabolism , Animals , Aquaporin 4/genetics , Astrocytes/cytology , Astrocytes/drug effects , Electric Stimulation , Enzyme Activation/drug effects , Enzyme Activation/genetics , Enzyme Inhibitors/pharmacology , Humans , Ion Channel Gating/drug effects , Ion Channel Gating/genetics , KCNQ1 Potassium Channel/genetics , KCNQ1 Potassium Channel/metabolism , Male , Membrane Potentials/drug effects , Membrane Potentials/genetics , Microinjections , Molecular Dynamics Simulation , Patch-Clamp Techniques , Permeability/drug effects , Phosphorylation , Potassium Channels, Voltage-Gated/genetics , Potassium Channels, Voltage-Gated/metabolism , Rats , Rats, Sprague-Dawley , Serine/genetics , Xenopus laevis
14.
Drug Deliv Transl Res ; 13(1): 37-53, 2023 01.
Article in English | MEDLINE | ID: mdl-35585472

ABSTRACT

General surgical procedures on the gastrointestinal tract are commonly performed worldwide. Surgical resections of the stomach, small intestine, or large intestine can have a significant impact on the anatomy and physiological environment of the gastrointestinal tract. These physiological changes can affect the effectiveness of orally administered formulations and drug absorption and, therefore, should be considered in rational drug formulation design for specific pathological conditions that are commonly associated with surgical intervention. For optimal drug delivery, it is important to understand how different surgical procedures affect the short-term and long-term functionality of the gastrointestinal tract. The significance of the surgical intervention is dependent on factors such as the specific region of resection, the degree of the resection, the adaptive and absorptive capacity of the remaining tissue, and the nature of the underlying disease. This review will focus on the common pathological conditions affecting the gastric and bowel regions that may require surgical intervention and the physiological impact of the surgery on gastrointestinal drug delivery. The pharmaceutical considerations for conventional and novel oral drug delivery approaches that may be impacted by general surgical procedures of the gastrointestinal tract will also be addressed.


Subject(s)
Drug Delivery Systems , Gastrointestinal Tract , Gastrointestinal Tract/surgery
15.
Matrix Biol ; 118: 16-46, 2023 04.
Article in English | MEDLINE | ID: mdl-36781087

ABSTRACT

High-grade serous ovarian cancer (HGSOC) is notoriously known as the "silent killer" of post-menopausal women as it has an insidious progression and is the deadliest gynaecological cancer. Although a dual origin of HGSOC is now widely accepted, there is growing evidence that most cases of HGSOC originate from the fallopian tube epithelium. In this review, we will address the fallopian tube origin and involvement of the extracellular matrix (ECM) in HGSOC development. There is limited research on the role of ECM at the earliest stages of HGSOC carcinogenesis. Here we aim to synthesise current understanding of the contribution of ECM to each stage of HGSOC development and progression, beginning at serous tubal intraepithelial carcinoma (STIC) precursor lesions and proceeding across key events including dissemination of tumourigenic fallopian tube epithelial cells to the ovary, survival of these cells in peritoneal fluid as multicellular aggregates, and colonisation of the ovary. Likewise, as part of the metastatic series of events, serous ovarian cancer cells survive travel in peritoneal fluid, attach to, migrate across the mesothelium and invade into the sub-mesothelial matrix of secondary sites in the peritoneal cavity. Halting cancer at the pre-metastatic stage and finding ways to stop the dissemination of ovarian cancer cells from the primary site is critical for improving patient survival. The development of drug resistance also contributes to poor survival statistics in HGSOC. In this review, we provide an update on the involvement of the ECM in metastasis and drug resistance in HGSOC. Interplay between different cell-types, growth factor gradients as well as evolving ECM composition and organisation, creates microenvironment conditions that promote metastatic progression and drug resistance of ovarian cancer cells. By understanding ECM involvement in the carcinogenesis and chemoresistance of HGSOC, this may prompt ideas for further research for developing new early diagnostic tests and therapeutic strategies for HGSOC with the end goal of improving patient health outcomes.


Subject(s)
Cystadenocarcinoma, Serous , Ovarian Neoplasms , Female , Humans , Ovarian Neoplasms/genetics , Cystadenocarcinoma, Serous/genetics , Extracellular Matrix/pathology , Carcinogenesis/genetics , Biology , Tumor Microenvironment
16.
Front Cell Dev Biol ; 11: 1198109, 2023.
Article in English | MEDLINE | ID: mdl-37293127

ABSTRACT

Local substrate stiffness is one of the major mechanical inputs for tissue organization during its development and remodeling. It is widely recognized that adherent cells use transmembrane proteins (integrins) at focal adhesions to translate ECM mechanical cues into intracellular bioprocess. Here we show that epithelial cells respond to substrate stiffening primarily via actin cytoskeleton organization, that requires activation of mechanosensitive Piezo1 channels. Piezo1 Knockdown cells eliminated the actin stress fibers that formed on stiff substrates, while it had minimal effect on cell morphology and spreading area. Inhibition of Piezo1 channels with GsMTx4 also significantly reduced stiffness-induced F-actin reorganization, suggesting Piezo1 mediated cation current plays a role. Activation of Piezo1 channels with specific agonist (Yoda1) resulted in thickening of F-actin fibers and enlargement of FAs on stiffer substrates, whereas it did not affect the formation of nascent FAs that facilitate spreading on the soft substrates. These results demonstrate that Piezo1 functions as a force sensor that couples with actin cytoskeleton to distinguish the substrate stiffness and facilitate epithelial adaptive remodeling.

17.
Drug Deliv ; 30(1): 2219423, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37344759

ABSTRACT

Diseases affecting the esophagus are common. However, targeted drug delivery to the esophagus is challenging due to the anatomy and physiology of this organ. Current pharmacological treatment for esophageal diseases predominantly relies on the off-label use of drugs in various dosage forms, including those for systemic drug delivery (e.g. oral tablets, sublingual tablets, and injections) and topical drug delivery (e.g. metered dose inhaler, viscous solution or suspension, and endoscopic injection into the esophagus). In general, systemic therapy has shown the most efficacy but requires the use of high drug doses to achieve effective concentrations in the esophagus, which increases the risk of adverse effects and toxicity. Topical drug delivery has enormous potential in improving the way we treat patients with acute and chronic esophageal diseases, especially those requiring drugs that have low therapeutic index and/or significant adverse effects to non-targeted organs and tissues. This review will address the physiological, pathophysiological, and pharmaceutical considerations influencing topical drug delivery in the esophagus. The main conventional (e.g. liquid formulations, orodispersible tablets, lozenges, pastilles, troches, chewing gum) and innovative (e.g. stent-based, film-based, nanoparticulate-based) drug delivery approaches will be comprehensively discussed, along with the developments to improve their effectiveness for topical esophageal drug delivery. The translational challenges and future clinical advances of this research will also be discussed.


Subject(s)
Drug Delivery Systems , Esophageal Diseases , Humans , Tablets/therapeutic use , Esophageal Diseases/drug therapy , Administration, Inhalation
18.
J Med Econ ; 26(1): 1424-1431, 2023.
Article in English | MEDLINE | ID: mdl-37855437

ABSTRACT

AIM: To assess the economic burden of different chemotherapies for lung cancer patients and influencing factors in China. MATERIALS AND METHODS: The economic burden of lung cancer, including direct, indirect and intangible costs was measured within three months after diagnosis and treatment. Direct cost included the cost of hospitalization, outpatient visits, out-of-pocket drug purchases, costs of transportation, accommodation and meal expenses while seeking treatments in hospitals. Cost information was attained from questionnaire and patients' medical record. Indirect cost was measured by the patients' and their caregivers' productive days lost due to outpatient visits and hospitalization for lung cancer treatment. Intangible cost was obtained through the willingness-to-pay method from a questionnaire completed by the patient. RESULTS: Among the total cost of CNY71,401.92, direct cost, indirect cost and intangible cost constituted 89.02%, 4.29%, and 6.69% respectively. Educational level, occupation, family income, lung cancer classification, and the city of residence significantly influenced the total cost. LIMITATIONS: Limitations in our study included: First, our follow-up period of three months was relatively short compared to the whole survival period of lung cancer patients. Second, the sample size of the chemotherapy combined with targeted therapy group was not large enough, and the cost data obtained would need confirmation in future studies. Third, participants came from only two localities, which may somewhat limit the representativeness of the study results for the whole of China. CONCLUSIONS: The economic burden of lung cancer treatment mainly came from the cost of the drugs. Patients taking chemotherapy had significantly higher cost compared to patients using targeted therapy. The cost was generally higher for those with higher educational level, those with higher family income, and those living in an economically more developed city. Patients with NSCLC had higher cost compared to patients with SCLC.


In China, lung cancer is the leading cause of cancer-related deaths and imparts a heavy economic burden. Most lung cancer patients are treated with chemotherapeutic and/of targeted agents because they are usually diagnosed at an advanced stage (IIIB or IV). The use of targeted therapy has achieved high response rates, longer overall survival, and longer progression-free survival compared with conventional chemotherapies. Adverse reactions with targeted therapeutic agents are usually mild compared with conventional chemotherapy. However, targeted drugs for lung cancer are usually more expensive than conventional chemotherapeutic drugs. It should be noted that the adverse effects and toxicities caused by chemotherapeutic drugs are generally more serious compared to targeted drugs; therefore, a number of measures are needed to prevent or relieve these reactions clinically. This can increase the financial burden of lung cancer treatment. Does these two treatments have a different cost? Our results showed that educational level, occupation, family income, classification of lung cancer, and the city of residence significantly influenced the total cost. Patients taking chemotherapy had significantly higher cost compared to patients using targeted therapy. This result suggests that targeted therapy for lung cancer is a better choice than chemotherapy.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Lung Neoplasms/drug therapy , Gefitinib/therapeutic use , Financial Stress , Carcinoma, Non-Small-Cell Lung/drug therapy , China
19.
Cell Physiol Biochem ; 30(2): 395-406, 2012.
Article in English | MEDLINE | ID: mdl-22759987

ABSTRACT

Using a microfluidic cell volume sensor we measured the change in the cell volume of Madin-Darby Canine Kidney (MDCK) cells induced by shear stress. An increase in shear stress from 0.2 to 2.0 dyn/cm(2) resulted in a volume decrease to a steady state volume ∼ 20 - 30 % smaller than the initial resting cell volume. Independent experiments based on fluorescence quenching confirmed the volume reduction. This shear-induced cell shrinkage was irreversible on the time scale of the experiment (∼ 30 min). Treatment of 0.1 µM Hg(2+) significantly inhibited the volume decrease, suggesting that the shear-induced cell shrinkage is associated with water efflux through aquaporins. The volume decrease cannot be inhibited by 75 mM TEA, 100 µM DIDS, or 100 µM Gd(3+) suggesting that volume reduction is not directly mediated by K(+) and Cl(-)channels that typically function during regulatory volume decrease (RVD), nor is it through cationic stretch-activated ion channels (SACs). The process also appears to be Ca(2+) independent because it was insensitive to intracellular Ca(2+) level. Since cell volume is determined by the intracellular water content, we postulate that the shear induced reductions in cell volume may arise from increased intracellular hydrostatic pressure as the cell is deformed under flow, which promotes the efflux of water. The increase in internal pressure in a deformable object under the flow is supported by the finite element mechanical model.


Subject(s)
Shear Strength , 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid/pharmacology , Animals , Calcium/metabolism , Cell Line , Cell Size/drug effects , Chloride Channels/metabolism , Dogs , Gadolinium/pharmacology , Mercury/pharmacology , Microfluidic Analytical Techniques , Potassium Channels/metabolism , Tetraethylammonium/pharmacology , Water/metabolism
20.
Front Vet Sci ; 9: 944578, 2022.
Article in English | MEDLINE | ID: mdl-35836504

ABSTRACT

Sarcoptic scabiei is an invasive parasitic mite that negatively impacts wombats, causing sarcoptic mange disease, characterized by alopecia, intense pruritus, hyperkeratosis, and eventual mortality. Evidence suggests that wombats may be unable to recovery from infection without the assistance of treatments. Transdermal drug delivery is considered the most ideal route of administration for in situ treatment in free-ranging wombats, as it is non-invasive and avoids the need to capture affected individuals. Although there are effective antiparasitic drugs available, an essential challenge is adequate administration of drugs and sufficient drug retention and absorption when delivered. This review will describe the implications of sarcoptic mange on the physiology of wombats as well as discuss the most widely used antiparasitic drugs to treat S. scabiei (ivermectin, moxidectin, and fluralaner). The prospects for improved absorption of these drugs will be addressed in the context of pathophysiological and pharmaceutical considerations influencing transdermal drug delivery in wombats with sarcoptic mange.

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