ABSTRACT
Various cardiovascular complications have been reported in patients with coronavirus disease 2019. Common complications include acute myocardial injury, myocarditis, arrhythmia, pericarditis, heart failure, and shock. We present a case of cor pulmonale diagnosed with serial point of care ultrasound. Given the current shortage of personal protective equipment (PPE) and high infectivity of this virus, we acknowledge the utility of this tool in obtaining important clinical information while minimizing exposure and PPE consumption.
Subject(s)
Betacoronavirus , Coronavirus Infections/complications , Echocardiography , Heart Failure/diagnostic imaging , Pneumonia, Viral/complications , Point-of-Care Systems , Pulmonary Heart Disease/diagnostic imaging , Aged , COVID-19 , Electrocardiography , Fatal Outcome , Heart Failure/diagnosis , Heart Failure/etiology , Humans , Male , Pandemics , Pulmonary Heart Disease/etiology , Respiratory Distress Syndrome/etiology , SARS-CoV-2 , Ventricular Dysfunction, RightABSTRACT
This study examined the physiological changes resulting from training on a lower body positive pressure treadmill (LBPPT) at three different levels of body weight support (BWS). Thirty-three healthy college aged students (22.3 ± 3.1 years) completed the study. Participants performed a graded exercise test (GXT) to exhaustion and were placed into one of three experimental groups corresponding to 100%, 75%, and 50% of their normal BW. Participants trained at their experimental BW levels for eight-weeks. Training speed was monitored by heart rate (HR) and speed was adjusted to elicit approximately 60% of participant's peak oxygen uptake (VÌO2peak) at normal BW prior to including body weight support (BWS). One-way analysis of variance (ANOVA) was used to compare the change in aerobic capacity. The 100% BW group improved their relative VÌO2peak (1.42 ± 1.52 ml · min-1 · kg-1) when compared to the 50% BW group (-0.87 ± 2.20 ml · min-1 · kg-1 [p = .022]) but not the 75% BW group (-0.16 ± 1.92 ml · min-1 · kg-1, [p = .14]). Furthermore, no statistical differences in VÌO2peak were observed between the 75% and 50% BW groups (p = .66). Based on this study, training at 75% and 50% of normal BW on a LBPPT does not improve aerobic capacity compared to training with no BWS when using training speeds derived from a GXT with full BW. The outcome of this study may help to prescribe training speeds while utilizing a LBPPT to maintain or improve aerobic capacity.
ABSTRACT
Canada's vast geography, and centralized delivery of cancer care and clinical trials create barriers for trial participation for patients in remote and rural settings. The development and implementation of a framework that enables safe and regulatory compliant trial participation through local healthcare providers would benefit Canadian patients, clinicians, trial sponsors and the health care system. To address this issue, representatives of Canada's cancer clinical trial community met to identify key challenges and develop recommendations for remote patient participation in trials. A structured literature review identified remote/rural trial delivery models. A panel of expert stakeholders reviewed the models and participated in a workshop to assess health system readiness, identify needed processes, tools and mechanisms, and develop recommendations for a Canadian framework for decentralized clinical trial conduct. The Canadian Remote Access Framework for clinical Trials (CRAFT) represents a risk-based approach used by site investigators to delegate responsibilities for a given trial to satellite health centres within a hub-and-spoke "trial cluster". The Framework includes specific recommendations to ensure research experience, capacity, regulatory compliance and patient safety. Canada's cancer care and telemedicine systems can be leveraged to enable broader access to clinical trials for patients who are geographically remote from cancer centres. CRAFT's risk-based framework is based on other successful models of remote trial patient management and is in the pilot implementation phase in Canada.
Subject(s)
Telemedicine , Canada , Delivery of Health Care , Humans , Rural PopulationABSTRACT
Therapeutic product development, licensing and reimbursement may seem a well-oiled machine, but continuing high attrition rates, regulatory refusals, and patients' access issues suggest otherwise; despite serious efforts, gaps persist between stakeholders' stated evidence requirements and actual evidence supplied. Evidentiary deficiencies and/or human tendencies resulting in avoidable inefficiencies might be further reduced with fresh institutional cultures/mindsets, combined with a context-adaptable practices framework that integrates emerging innovations. Here, Structured Evidence Planning, Production, and Evaluation (SEPPE) posits that evidence be treated as something produced, much like other manufactured goods, for which "built-in quality" (i.e., "people" and "process") approaches have been successfully implemented globally. Incorporating proactive, iterative feedback-and-adjust loops involving key decision-makers at critical points could curtail avoidable evidence quality and decision hazards-pulling needed therapeutic products with high quality evidence of beneficial performance through to approvals. Critical for success, however, is dedicated, long-term commitment to systemic transformation.
Subject(s)
Drug Development/standards , Drug Industry/standards , HumansABSTRACT
The metallopeptidase angiotensin-converting enzyme (ACE) plays a pivotal role in the cardiovascular system by generating the vasoconstrictor peptide angiotensin II. A homolog of ACE with different substrate specificity, ACE2, has recently been cloned that shows an expression pattern restricted to endothelial cells of the heart and kidney, epithelial cells of the distal tubule of the kidney, and the testis. Although the importance of ACE2 to cardiac function is already evident, its role in the testis remains unknown. In this study, we report the cloning and expression of human testicular ACE2 and confirm that it is identical to the somatic form of the enzyme. ACE2 catalytic activity was present in membrane preparations of whole testes and Leydig cells from adult rats; expression of the protein in Leydig cells was confirmed by Western immunoblot analysis. Using immunohistochemistry, ACE2 expression was confined to the Leydig cells in the rat testis and to Leydig and Sertoli cells in the human testis. Ablation of the Leydig cells in the rat by the specific toxin, ethane dimethane sulfonate, eliminated ACE2-positive cells from the interstitium. Expression of ACE2 in rat Leydig cells was up-regulated during the development of adult-type Leydig cells at puberty and after ethane dimethane sulfonate treatment. Expression of ACE2 activity in the testis was not significantly altered by manipulation of the pituitary-testicular hormonal axis with sc testosterone implants. These data suggest that ACE2 is a constitutive product of adult-type Leydig cells and may participate in the control of testicular function by as yet unknown mechanisms.
Subject(s)
Carboxypeptidases/metabolism , Leydig Cells/enzymology , Angiotensin-Converting Enzyme 2 , Animals , Blotting, Western , CHO Cells , Carboxypeptidases/genetics , Carboxypeptidases/physiology , Catalysis , Cloning, Molecular , Cricetinae , Cricetulus , Gene Expression , Humans , Immunohistochemistry/methods , Male , Peptidyl-Dipeptidase A , Rats , Rats, Sprague-Dawley , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Staining and Labeling , Subcellular Fractions/enzymology , Tissue DistributionABSTRACT
An orphan drug is a pharmaceutical or biological drug that is used to treat a rare disease. The development of a Canadian orphan drug framework is intended to help translate scientific discoveries into meaningful results for Canadian rare disease patients.
Subject(s)
Orphan Drug Production/legislation & jurisprudence , Rare Diseases/drug therapy , Canada , HumansABSTRACT
Numerous studies have shown that selective nNOS inhibitors could be therapeutic in many neurological disorders. Previously, we reported a series of 1,2,3,4-tetrahydroquinoline-based potent and selective nNOS inhibitors, highlighted by 1 ( J. Med. Chem. 2011 , 54 , 5562 - 5575 ). Despite showing activity in two rodent pain models, 1 suffered from low oral bioavailability (18%) and moderate hERG channel inhibition (IC(50) = 4.7 µM). To optimize the properties of 1, we synthesized a small focused library containing various alkylamino groups on the 1-position of the 1,2,3,4-tetrahydroquinoline scaffold. The compounds were triaged based on their activity in the NOS and hERG manual patch clamp assays and their calculated physicochemical parameters. From these studies, we identified 47 as a potent and selective nNOS inhibitor with improved oral bioavailability (60%) and no hERG channel inhibition (IC(50) > 30 µM). Furthermore, 47 was efficacious in the Chung model of neuropathic pain and has an excellent safety profile, making it a promising preclinical development candidate.
Subject(s)
Nitric Oxide Synthase Type I/antagonists & inhibitors , Quinolines/chemical synthesis , Thiophenes/chemical synthesis , Administration, Oral , Analgesics/chemical synthesis , Analgesics/pharmacokinetics , Analgesics/pharmacology , Animals , Biological Availability , ERG1 Potassium Channel , Ether-A-Go-Go Potassium Channels/antagonists & inhibitors , Ether-A-Go-Go Potassium Channels/physiology , High-Throughput Screening Assays , Humans , Neuralgia/drug therapy , Nitric Oxide Synthase Type I/physiology , Patch-Clamp Techniques , Quinolines/pharmacokinetics , Quinolines/pharmacology , Rats , Small Molecule Libraries , Structure-Activity Relationship , Thiophenes/pharmacokinetics , Thiophenes/pharmacologyABSTRACT
(2)H T(1) NMR relaxation was used to characterize the molecular motion of deuterated water ((2)H(2)O) in Aquivion E87-05, Nafion 117, and sulfonated-Radel proton-exchange membranes. The presence of bound water with solid character was confirmed by the dependence of the (2)H T(1) relaxation on the magnetic field of the spectrometer. By comparing the (2)H T(1) relaxation times of the different membranes that were equilibrated in varying humidities, the factors that influence the state of water in the membranes were identified. At low levels of hydration, the molecular motion of (2)H(2)O is affected by the acidity and mobility of the sulfonic acid groups to which the water molecules are coordinated. At higher levels of hydration, the molecular motion of (2)H(2)O is affected by the phase separation of the hydrophilic/hydrophobic domains and the size of the hydrophilic domains.
ABSTRACT
3,6-Disubstituted indole derivatives were designed, synthesized, and evaluated as inhibitors of human nitric oxide synthase (NOS). Bulky amine containing substitution on the 3-position of the indole ring such as an azabicyclic system showed better selectivity over 5- and 6-membered cyclic amine substitutions. Compound (-)-19 showed the best selectivity for neuronal NOS over endothelial NOS (90-fold) and inducible NOS (309-fold) among the current series. Compounds 16 and (-)-19 were shown to be either inactive or very weak inhibitors of human cytochrome P450 enzymes, indicating a low potential for drug-drug interactions. Compound 16 was shown to reverse thermal hyperalgesia in vivo in the Chung model of neuropathic pain. Compound 16 was also devoid of any significant vasoconstrictive effect in human coronary arteries, associated with the inhibition of human eNOS. These results suggest that 16 may be a useful tool for evaluating the potential role of selective nNOS inhibitors in the treatment of pain such as migraine and CTTH.
Subject(s)
Analgesics/chemical synthesis , Indoles/chemical synthesis , Nitric Oxide Synthase Type I/antagonists & inhibitors , Pain/drug therapy , Pyridines/chemical synthesis , Thiophenes/chemical synthesis , Analgesics/chemistry , Analgesics/pharmacology , Coronary Vessels/drug effects , Coronary Vessels/physiology , Cytochrome P-450 Enzyme Inhibitors , Hot Temperature , Humans , Hyperalgesia/drug therapy , Indoles/chemistry , Indoles/pharmacology , Ligation , Neuralgia/drug therapy , Neuralgia/etiology , Pyridines/chemistry , Pyridines/pharmacology , Spinal Nerves/injuries , Stereoisomerism , Structure-Activity Relationship , Thiophenes/chemistry , Thiophenes/pharmacology , Vascular Resistance , Vasoconstriction/drug effectsABSTRACT
Neuronal nitric oxide synthase (nNOS) inhibitors are effective in preclinical models of many neurological disorders. In this study, two related series of compounds, 3,4-dihydroquinolin-2(1H)-one and 1,2,3,4-tetrahydroquinoline, containing a 6-substituted thiophene amidine group were synthesized and evaluated as inhibitors of human nitric oxide synthase (NOS). A structure-activity relationship (SAR) study led to the identification of a number of potent and selective nNOS inhibitors. Furthermore, a few representative compounds were shown to possess druglike properties, features that are often difficult to achieve when designing nNOS inhibitors. Compound (S)-35, with excellent potency and selectivity for nNOS, was shown to fully reverse thermal hyperalgesia when given to rats at a dose of 30 mg/kg intraperitonieally (ip) in the L5/L6 spinal nerve ligation model of neuropathic pain (Chung model). In addition, this compound reduced tactile hyperesthesia (allodynia) after oral administration (30 mg/kg) in a rat model of dural inflammation relevant to migraine pain.
Subject(s)
Nitric Oxide Synthase Type I/antagonists & inhibitors , Quinolines/therapeutic use , Animals , Humans , Hyperalgesia/drug therapy , Male , Migraine Disorders/drug therapy , Neuralgia/drug therapy , Quinolines/chemical synthesis , Quinolines/pharmacokinetics , Rats , Rats, Sprague-Dawley , Structure-Activity RelationshipABSTRACT
Two novel cyclic phosphazenes with asymmetric spiro rings were synthesized via reactions of hexachlorocyclotriphosphazene with chiral amino alcohol residues. The reactions showed preferential formation of the cis isomer possibly due to the delocalization of the lone pair electrons of the spirocylic nitrogen, which reduces its ability to solvate protons. Crystals of these phosphazenes were analyzed by X-ray crystallography which confirmed the formation of cis isomers and showed their ability to include guest molecules within the crystal lattices. The selective inclusion of epoxides by one of the phosphazenes was an effective method for the separation of thermally sensitive guest molecules.
Subject(s)
Heterocyclic Compounds, 1-Ring/chemical synthesis , Organophosphorus Compounds/chemical synthesis , Spiro Compounds/chemical synthesis , Crystallography, X-Ray , Heterocyclic Compounds, 1-Ring/chemistry , Isomerism , Molecular Conformation , Organophosphorus Compounds/chemistry , Phosphoranes/chemistry , Spiro Compounds/chemistryABSTRACT
Synthesis and in vitro cytotoxicity assays of new anthranilamide MDR modulators have been performed to assess their inhibition potency on the P-glycoprotein (P-gp) transporter. Previous studies showed that the replacement of the aromatic spacer group between nitrogen atoms (N(1) and N(2)) in the P-gp inhibitor XR9576 with ethyl or propyl chain is optimal for P-gp inhibition potency. To confirm that observation, the ethyl or the propyl linker arm was replaced with a pyrrolidine or an alicyclic group such as cyclohexyl. In addition, an arylpiperazinyl group and two methoxyl groups onto the anthranilic part were introduced to assess their effect on the anti P-gp activity. Five molecules were prepared and evaluated on CEM/VLB500. All new anthranilamides were more potent than verapamil, most of them exhibited a lower cytotoxicity than XR9576. Compound 5 was the most potent and its inhibition activity was similar to XR9576. Interestingly, in vitro biotransformation studies of compounds 4 and 5 using human CYP-450 isoforms revealed, that conversely to XR9576, compounds 4 and 5 inhibited CYP3A4, an enzyme that colocalizes with P-gp in the intestine and contributes to tumor cell chemoresistance by enhancing the biodisposition of numerous drugs, notably paclitaxel. In that context, 5 might be suitable for further drug development.
Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors , Cytochrome P-450 Enzyme Inhibitors , Drug Resistance, Multiple/drug effects , Drug Resistance, Neoplasm/drug effects , Pyrazines/chemistry , Pyrazines/pharmacology , Quinolines/chemistry , Quinolines/pharmacology , ATP Binding Cassette Transporter, Subfamily B, Member 1/analysis , Biological Assay , Cell Line, Tumor , Cytochrome P-450 CYP3A , Cytochrome P-450 Enzyme System/analysis , Humans , Intestines/enzymology , Pyrazines/chemical synthesis , Quinolines/chemical synthesis , ortho-Aminobenzoates/chemistryABSTRACT
Synthesis and in vitro cytotoxicity assays of new anthranilamide MDR modulators have been performed to assess their inhibition potency of the P-glycoprotein (P-gp) transporter. The aromatic spacer group between nitrogen atoms (N1 and N2) in the known inhibitor XR9576 was replaced with a flexible alkyl chain of 2 to 6 carbon atoms in length. 6,7-Dimethoxy-1,2,3,4-tetrahydroisoquinoline and their open-chain N-methylhomoveratrylamine counterparts were shown to be potent P-gp inhibitors. The maximal inhibition was obtained when using an ethyl or propyl spacer. Several compounds were more potent than verapamil and intrinsically less cytotoxic than XR9576. In addition, in vitro metabolism studies of 23a with a subset of human CYP-450 isoforms revealed that, unlike XR9576, 23a inhibited CYP3A4, an enzyme that colocalizes with P-gp in the intestine and contributes to tumor cell chemoresistance by enhancing the biodisposition of anticancer drugs such as paclitaxel toward metabolism. In this context, 22a might be a suitable candidate for further drug development.
Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors , Cytochrome P-450 Enzyme Inhibitors , Drug Resistance, Multiple/drug effects , ortho-Aminobenzoates/chemical synthesis , ortho-Aminobenzoates/pharmacology , ATP-Binding Cassette Transporters/antagonists & inhibitors , Cytochrome P-450 CYP3A , Humans , Quinolines , Structure-Activity Relationship , ortho-Aminobenzoates/chemistryABSTRACT
A new class of potent dopamine D(4) antagonists was discovered with selectivity over dopamine D(2) and the alpha-1 adrenoceptor. The lead compound was discovered by screening our compound collection. The structure-activity relationships of substituted isoindoline rings and the chirality about the hydroxymethyl side chain were explored. The isoindoline analogues showed modest differences in potency and selectivity. The S enantiomer proved to be the more potent enantiomer at the D(4) receptor. Several analogues with greater than 100-fold selectivity for D(4) over D(2) and the alpha-1 adrenoreceptor were discovered. Several selective analogues were active in vivo upon oral or intraperitoneal administration. A chiral synthesis starting from either D- or L-O-benzylserine is also described.