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1.
J Manipulative Physiol Ther ; 42(5): 327-334, 2019 06.
Article in English | MEDLINE | ID: mdl-31257004

ABSTRACT

OBJECTIVES: The purpose of this paper is to describe the 4-step process (consent, selection, protection, and abstraction) of acquiring a large sample of chiropractic patient records from multiple practices and subsequent data abstraction. METHODS: From April 2017 to December 2017, RAND acquired patient records from 99 chiropractic practices across the United States. The records included patients enrolled in a survey e-study (prospective sample) and a random sample of all clinic patients (retrospective sample) with chronic back or neck pain. Clinic staff were trained to collect the sample, scan, and transfer the records. We designed an online data collection tool for abstraction. Protocols were instituted to protect patient confidentiality. Doctors of chiropractic were selected and trained as abstractors, and a system was established to monitor data collection. RESULTS: In compliance with data protection protocols, 3603 patient records were scanned, including 1475 in the prospective sample and 2128 in the random sample. A total of 1716 patients (prospective sample) consented to having their records scanned, but only 1475 could be retrieved. Of records scanned, 19% were unusable owing to illegibility, no care during the period of interest, or poor scanning. The abstractor interrater reliability for appropriateness of care decisions was fair to moderate (κ .38-.48). CONCLUSION: The acquisition, handling, and abstraction of a large sample of chiropractic records was a complex task with challenges that necessitated adapting planned approaches. Of the records abstracted, many revealed incomplete provider documentation regarding the details of and rationale for care. Better documentation and more standardized record keeping would facilitate future research using patient records.


Subject(s)
Abstracting and Indexing , Computer Security , Confidentiality , Medical Records , Patient Selection , Ambulatory Care Facilities , Chiropractic , Chronic Pain/therapy , Data Collection , Humans , Informed Consent , Low Back Pain/therapy , Manipulation, Chiropractic , Neck Pain/therapy , United States
2.
Pharmacol Res Perspect ; 5(2): e00295, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28357122

ABSTRACT

Plecanatide is a recently developed guanylate cyclase-C (GC-C) agonist and the first uroguanylin analog designed to treat chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (IBS-C). GC-C receptors are found across the length of the intestines and are thought to play a key role in fluid regulation and electrolyte balance. Ligands of the GC-C receptor include endogenous agonists, uroguanylin and guanylin, as well as diarrheagenic, Escherichia coli heat-stable enterotoxins (ST). Plecanatide mimics uroguanylin in its 2 disulfide-bond structure and in its ability to activate GC-Cs in a pH-dependent manner, a feature associated with the presence of acid-sensing residues (Asp2 and Glu3). Linaclotide, a synthetic analog of STh (a 19 amino acid member of ST family), contains the enterotoxin's key structural elements, including the presence of three disulfide bonds. Linaclotide, like STh, activates GC-Cs in a pH-independent manner due to the absence of pH-sensing residues. In this study, molecular dynamics simulations compared the stability of plecanatide and linaclotide to STh. Three-dimensional structures of plecanatide at various protonation states (pH 2.0, 5.0, and 7.0) were simulated with GROMACS software. Deviations from ideal binding conformations were quantified using root mean square deviation values. Simulations of linaclotide revealed a rigid conformer most similar to STh. Plecanatide simulations retained the flexible, pH-dependent structure of uroguanylin. The most active conformers of plecanatide were found at pH 5.0, which is the pH found in the proximal small intestine. GC-C receptor activation in this region would stimulate intraluminal fluid secretion, potentially relieving symptoms associated with CIC and IBS-C.

3.
World J Gastrointest Pharmacol Ther ; 6(4): 213-22, 2015 Nov 06.
Article in English | MEDLINE | ID: mdl-26558155

ABSTRACT

AIM: To evaluate the effect of orally administered plecanatide or dolcanatide, analogs of uroguanylin, on amelioration of colitis in murine models. METHODS: The cyclic guanosine monophosphate (cGMP) stimulatory potency of plecanatide and dolcanatide was measured using a human colon carcinoma T84 cell-based assay. For animal studies all test agents were formulated in phosphate buffered saline. Sulfasalazine or 5-amino salicylic acid (5-ASA) served as positive controls. Effect of oral treatment with test agents on amelioration of acute colitis induced either by dextran sulfate sodium (DSS) in drinking water or by rectal instillation of trinitrobenzene sulfonic (TNBS) acid, was examined in BALB/c and/or BDF1 mice. Additionally, the effect of orally administered plecanatide on the spontaneous colitis in T-cell receptor alpha knockout (TCRα(-/-)) mice was also examined. Amelioration of colitis was assessed by monitoring severity of colitis, disease activity index and by histopathology. Frozen colon tissues were used to measure myeloperoxidase activity. RESULTS: Plecanatide and dolcanatide are structurally related analogs of uroguanylin, which is an endogenous ligand of guanylate cyclase-C (GC-C). As expected from the agonists of GC-C, both plecanatide and dolcanatide exhibited potent cGMP-stimulatory activity in T84 cells. Once-daily treatment by oral gavage with either of these analogs (0.05-0.5 mg/kg) ameliorated colitis in both DSS and TNBS-induced models of acute colitis, as assessed by body weight, reduction in colitis severity (P < 0.05) and disease activity index (P < 0.05). Amelioration of colitis by either of the drug candidates was comparable to that achieved by orally administered sulfasalazine or 5-ASA. Plecanatide also effectively ameliorated colitis in TCRα(-/-) mice, a model of spontaneous colitis. As dolcanatide exhibited higher resistance to proteolysis in simulated gastric and intestinal juices, it was selected for further studies. CONCLUSION: This is the first-ever study reporting the therapeutic utility of GC-C agonists as a new class of orally delivered and mucosally active drug candidates for the treatment of inflammatory bowel diseases.

4.
Dig Dis Sci ; 58(9): 2580-6, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23625291

ABSTRACT

PURPOSE: Plecanatide, an analogue of uroguanylin, activates the guanylate cyclase C (GC-C) receptor found on the GI mucosal epithelial cells, leading to secretion of fluid, facilitating bowel movements. Plecanatide is being investigated as a potential treatment for constipating GI disorders. The aim of this investigation was to assess the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of single doses of plecanatide in healthy volunteers. METHODS: A total of 72 healthy volunteers at a single site were randomized in 9 cohorts to receive oral plecanatide or placebo from 0.1 to 48.6 mg. Plasma PK samples were collected pre-dose and post-dose. PD assessments included time to first stool, stool frequency, and stool consistency using the Bristol Stool Form Scale. All adverse events were documented. RESULTS: Plecanatide was safe and well-tolerated at all dose levels. A total of 17 of 71 subjects (23.9%) reported 25 treatment-emergent adverse events (TEAEs) during the study. The number of TEAEs reported by subjects who received plecanatide or placebo was comparable (24.5 vs. 22.2%, respectively). There were no dose-related increases in TEAEs or any SAEs reported. No measurable systemic absorption of oral plecanatide was observed at any of the oral doses studied, utilizing an assay sensitive down to 1 ng/mL. CONCLUSIONS: Plecanatide, an oral GC-C agonist, acting locally within the GI tract without measurable systemic exposure, was safe and well-tolerated in single doses up to 48.6 mg. The study was not powered for statistical analyses, but trends in PD parameters supported continued clinical development.


Subject(s)
Colonic Diseases, Functional/drug therapy , Defecation/drug effects , Natriuretic Peptides/adverse effects , Receptors, Atrial Natriuretic Factor/agonists , Administration, Oral , Adolescent , Adult , Drug Administration Schedule , Female , Humans , Intestinal Mucosa/drug effects , Male , Middle Aged , Natriuretic Peptides/pharmacokinetics , Young Adult
5.
Mol Cancer Ther ; 6(1): 112-21, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17237271

ABSTRACT

Atiprimod is a novel anticancer and antiangiogenic drug candidate which is currently being evaluated in patients with liver carcinoid and multiple myeloma. In this study, we report that atiprimod selectively inhibited proliferation and induced apoptosis in HCC cells that expressed either hepatitis B virus (HBV) or hepatitis C virus, through deactivation of protein kinase B (Akt) and signal transducers and activators of transcription 3 (STAT3) signaling. In HepG2 AD38 cells, which express HBV genome under the control of a tetracycline-off promoter, both Akt and STAT3 were constitutively activated in response to HBV expression. However, this constitutive activation was not sensitive to lamivudine, a drug that inhibits HBV replication without affecting its gene expression, suggesting that HBV replication per se might not be responsible for the activation. Interestingly, the electrophoretic mobility of p-STAT3 protein bands on immunoblot was slower when AD38 cells were cultured in the absence of tetracycline, suggesting a differential phosphorylation in response to HBV expression. In HCC cells, interleukin 6 stimulates the phosphorylation of STAT3 both at serine 727 and at tyrosine 705 positions. The interleukin 6-stimulated activation of STAT3 and Akt was inhibited not only by atiprimod but also by LY294002, a phosphoinositide-3-kinase-specific inhibitor, and by NS398, a cyclooxygenase-2-selective inhibitor. The combination of these compounds did not produce any additive effect, implying that the mechanisms by which HBV activates Akt and STAT3 might also involve phosphoinositide-3-kinase and cyclooxygenase-2. Collectively, these results suggest that atiprimod could be useful as a multifunctional drug candidate for the treatment of HCC in humans.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Proto-Oncogene Proteins c-akt/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction/drug effects , Spiro Compounds/pharmacology , Carcinoma, Hepatocellular/virology , Cell Proliferation/drug effects , Cyclooxygenase 2/metabolism , Enzyme Activation/drug effects , Gene Expression Regulation, Viral/drug effects , Hepacivirus/genetics , Hepacivirus/physiology , Hepatitis B virus/genetics , Hepatitis B virus/physiology , Humans , Interleukin-6/pharmacology , Liver Neoplasms/virology , Models, Biological , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation/drug effects , Virus Replication/drug effects
6.
Blood ; 106(2): 713-6, 2005 Jul 15.
Article in English | MEDLINE | ID: mdl-15817674

ABSTRACT

We developed a novel in vivo multiple myeloma (MM) model by engrafting the interleukin 6 (IL-6)-dependent human MM cell line INA-6 into severe combined immunodeficiency (SCID) mice previously given implants of a human fetal bone chip (SCID-hu mice). INA-6 cells require either exogenous human IL-6 (huIL-6) or bone marrow stromal cells (BMSCs) to proliferate in vitro. In this model, we monitored the in vivo growth of INA-6 cells stably transduced with a green fluorescent protein (GFP) gene (INA-6GFP+ cells). INA-6 MM cells engrafted in SCID-hu mice but not in SCID mice that had not been given implants of human fetal bone. The level of soluble human IL-6 receptor (shuIL-6R) in murine serum and fluorescence imaging of host animals were sensitive indicators of tumor growth. Dexamethasone as well as experimental drugs, such as Atiprimod and B-B4-DM1, were used to confirm the utility of the model for evaluation of anti-MM agents. We report that this model is highly reproducible and allows for evaluation of investigational drugs targeting IL-6-dependent MM cells in the human bone marrow (huBM) milieu.


Subject(s)
Multiple Myeloma/pathology , Animals , Bone Transplantation , Cell Line, Tumor , Dexamethasone/pharmacology , Disease Models, Animal , Fetal Tissue Transplantation , Green Fluorescent Proteins/genetics , Humans , Immunotoxins/pharmacology , Mice , Mice, SCID , Multiple Myeloma/drug therapy , Multiple Myeloma/genetics , Multiple Myeloma/immunology , Neoplasm Transplantation , Receptors, Interleukin-6/blood , Recombinant Proteins/genetics , Spiro Compounds/pharmacology , Transduction, Genetic , Transplantation, Heterologous
7.
Blood ; 105(11): 4470-6, 2005 Jun 01.
Article in English | MEDLINE | ID: mdl-15705788

ABSTRACT

Azaspirane (N-N-diethyl-8,8-dipropyl-2-azaspiro [4.5] decane-2-propanamine; trade name, Atiprimod) is an orally bioavailable cationic amphiphilic compound that significantly inhibits production of interleukin 6 (IL-6) and inflammation in rat arthritis and autoimmune animal models. We here characterize the effect of atiprimod on human multiple myeloma (MM) cells. Azaspirane significantly inhibited growth and induced caspase-mediated apoptosis in drug-sensitive and drug-resistant MM cell lines, as well as patient MM cells. IL-6, insulin-like growth factor 1 (IGF-1), or adherence of MM cells to bone marrow stromal cells (BMSCs) did not protect against atiprimod-induced apoptosis. Both conventional (dexamethasone, doxorubicin, melphalan) and novel (arsenic trioxide) agents augment apoptosis induced by atiprimod. Azaspirane inhibits signal transducer activator of transcription 3 (STAT3) and a PI3-K (phosphatidylinositol 3-kinase) target (Akt), but not extracellular signal-regulated kinase 1 and 2 (ERK1/2), inhibits phosphorylation triggered by IL-6, and also inhibits inhibitorkappaBalpha (IkappaBalpha) and nuclear factor kappaB (NFkappaB) p65 phosphorylation triggered by tumor necrosis factor alpha (TNF-alpha). Of importance, azaspirane inhibits both IL-6 and vascular endothelial growth factor (VEGF) secretion in BMSCs triggered by MM cell binding and also inhibits angiogenesis on human umbilical vein cells (HUVECs). Finally, azaspirane demonstrates in vivo antitumor activity against human MM cell growth in severe combined immunodeficient (SCID) mice. These results, therefore, show that azaspirane both induces MM cell apoptosis and inhibits cytokine secretion in the BM milieu, providing the framework for clinical trials to improve patient outcome in MM.


Subject(s)
Bone Marrow/pathology , Multiple Myeloma/drug therapy , Spiro Compounds/pharmacology , Animals , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Communication , Cell Proliferation/drug effects , Drug Synergism , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Humans , Interleukin-6/antagonists & inhibitors , Interleukin-6/metabolism , Mice , Mice, SCID , Multiple Myeloma/pathology , Neovascularization, Physiologic/drug effects , Signal Transduction/drug effects , Spiro Compounds/therapeutic use , Stromal Cells/drug effects , Stromal Cells/metabolism , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vascular Endothelial Growth Factor A/metabolism
8.
J Exp Ther Oncol ; 4(4): 267-79, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15844657

ABSTRACT

Atiprimod, a novel compound belonging to the azaspirane class of cationic amphiphilic drugs, exhibits both anti-proliferative and anti-angiogenic activities. Atiprimod inhibited proliferation of all human cancer cell lines included in the National Cancer Institute panel with IC50 values in the low micromolar range. Notably, metastatic cell lines were more sensitive to the compound compared to the non-metastatic cell lines derived from the same tumor tissue types. Atiprimod also induced apoptosis and activated both caspase-9 and caspase-3 in T84 colon carcinoma cells. Hence, the anti-proliferative activity could partly be due to its pro-apoptotic activity. Regarding angiogenesis in vitro, atiprimod inhibited both bFGF and VEGF induced proliferation and migration of human umbilical vein endothelial cells (HUVECs), resulting in disruption of cord formation. In addition, atiprimod also suppressed formation of new blood vessels in a chorioallantoic membrane assay. Previous studies have also shown that atiprimod treatment reduced production of IL-6, VEGF and inhibited activation of Stat3, a constitutively activated protein in majority of human cancers. Together these findings suggest that atiprimod acts on several molecules that are essential for tumor growth, invasion and metastasis.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Neoplasms/drug therapy , Neovascularization, Pathologic , Spiro Compounds/pharmacology , Apoptosis , Caspase 3 , Caspase 9 , Caspases/metabolism , Cations , Cell Line, Tumor , Cell Movement , Cell Proliferation/drug effects , Cells, Cultured , Collagen/pharmacology , Cytokines/metabolism , DNA-Binding Proteins/metabolism , Dose-Response Relationship, Drug , Down-Regulation , Drug Combinations , Endothelium, Vascular/cytology , Enzyme Activation , Fibroblast Growth Factor 2/metabolism , Humans , Inhibitory Concentration 50 , Laminin/pharmacology , Models, Chemical , Neoplasm Invasiveness , Neoplasm Metastasis , Proteoglycans/pharmacology , STAT3 Transcription Factor , Trans-Activators/metabolism , Vascular Endothelial Growth Factor A/metabolism
9.
IEEE Trans Med Imaging ; 21(3): 226-38, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11989847

ABSTRACT

This paper presents a new semi-automatic method for quantifying regional heart function from two-dimensional echocardiography. In the approach, we first track the endocardial and epicardial boundaries using a new variant of the dynamic snake approach. The tracked borders are then decomposed into clinically meaningful regional parameters, using a novel interpretational shape-space motivated by the 16-segment model used in clinical practice for qualitative assessment of heart function. We show how a quantitative and automatic scoring scheme for the endocardial excursion and myocardial thickening can be derived from this. Results illustrating our approach on apical long-axis two-chamber-view data from a patient with a myocardial infarct in the apical anterior/inferior region of the heart are presented. In a case study (five patients, nine data sets) the performance of the tracking and interpretation techniques are compared with manual delineations of borders using a number of quantitative measures of regional comparison.


Subject(s)
Echocardiography/methods , Image Interpretation, Computer-Assisted/methods , Models, Cardiovascular , Myocardial Contraction , Myocardial Infarction/diagnostic imaging , Ventricular Dysfunction, Left/diagnostic imaging , Algorithms , Elasticity , Heart/physiopathology , Humans , Image Enhancement/methods , Models, Statistical , Movement , Myocardial Infarction/physiopathology , Sensitivity and Specificity
10.
Antivir Chem Chemother ; 13(5): 299-304, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12630678

ABSTRACT

Imino sugar glucosidase inhibitors have selective antiviral activity against certain enveloped, mammalian viruses. Deoxynojirimycins (DNJs) modified by N-alkylation to contain a nine carbon atom side chain (N-n-nonyl-deoxynojirimycin; N-nonyl-DNJ, NN-DNJ) were shown to be, for example, at least 20 times more potent in inhibiting hepatitis B virus (HBV) and bovine viral diarrhoea virus (BVDV) in cell based assays than the non-alkylated DNJ. These data suggested that modification of the alkyl side chain could influence antiviral activity. Previous work has focused on varying side chain length. In this report, the influence of side chain branching and cyclization upon toxicity and antiviral activity was explored. Briefly, using a virus secretion assay for HBV and a single step growth (yield reduction) assay for BVDV, 14 different DNJ-based sugars, possessing various N-alkyl substitutions, were tested for antiviral activity. Of the series, N-methoxy-nonyl-DNJ and N-butyl-cyclohexyl DNJ were determined to have the best selectivity index against BVDV and HBV, with the N-methoxy analogue being the most potent with micromolar antiviral activity. The results of this antiviral survey and the implications for the mechanism of action and ultimate therapeutic potential of the DNJ-based imino sugars is provided and discussed.


Subject(s)
Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Carbohydrates/chemistry , Carbohydrates/pharmacology , Glucosamine/analogs & derivatives , Glucosamine/chemistry , Glucosamine/pharmacology , 1-Deoxynojirimycin/analogs & derivatives , 1-Deoxynojirimycin/toxicity , Alkylation , Animals , Antiviral Agents/toxicity , Carbohydrates/toxicity , Cell Line , Cyclization , Diarrhea Viruses, Bovine Viral/drug effects , Glucosamine/toxicity , Hepatitis B virus/drug effects , Humans , Molecular Structure
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