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1.
J Gen Intern Med ; 38(1): 57-66, 2023 01.
Article in English | MEDLINE | ID: mdl-35604632

ABSTRACT

BACKGROUND: Women are underrepresented within internal medicine (IM). Whether women leaders attract women trainees is not well explored. OBJECTIVE: To characterize leader and trainee gender across US academic IM and to investigate the association of leader gender with trainee gender. DESIGN: Cross-sectional study. PARTICIPANTS: Leaders (chairs, chiefs, program directors (PDs)) in 2018 and trainees (residents, fellows) in 2012-2016 at medical school-affiliated IM and seven IM fellowship programs. EXPOSURE: Leadership (chair/chief and program director; and, for resident analyses, fellow) gender. MAIN MEASURES: Our primary outcome was percent women trainees (IM residents and, separately, subspecialty fellows). We used standard statistics to describe leadership and trainee gender. We created separate multivariable linear regressions to evaluate associations of leader gender and percent women fellows with percent women IM residents. We then created separate multivariable multilevel models (site as a random effect) to evaluate associations of leader gender with percent women subspecialty fellows. KEY RESULTS: Our cohort consisted of 940 programs. Women were 13.4% of IM chairs and <25% of chiefs in each fellowship subspecialty (cardiology: 2.6%; gastroenterology: 6.6%; pulmonary and critical care: 10.7%; nephrology: 14.4%; endocrinology: 20.6%; hematology-oncology: 23.2%; infectious diseases: 24.3%). IM PDs were 39.7% women; fellowship PDs ranged from nearly 25% (cardiology and gastroenterology) to nearly 50% (endocrinology and infectious disease) women. Having more women fellows (but not chairs or PDs) was associated with having more women residents (0.3% (95% CI: 0.2-0.5%) increase per 1% fellow increase, p<0.001); this association remained after adjustment (0.3% (0.1%, 0.4%), p=0.001). In unadjusted analyses, having a woman PD (increase of 7.7% (4.7%, 10.6%), p<0.001) or chief (increase of 8.9% (4.6%, 13.1%), p<0.001) was associated with an increase in women fellows; after adjustment, these associations were lost. CONCLUSIONS: Women held a minority of leadership positions in academic IM. Having women leaders was not independently associated with having more women trainees.


Subject(s)
Cardiology , Faculty, Medical , Humans , Female , United States/epidemiology , Male , Cross-Sectional Studies , Medical Oncology , Leadership , Fellowships and Scholarships
2.
Article in English | MEDLINE | ID: mdl-34164564

ABSTRACT

The coronavirus SARS-CoV-2 is cause of a global pandemic of a pneumonia-like disease termed Coronavirus Disease 2019 (COVID-19). COVID-19 presents a high mortality rate, estimated at 3.4%. More than 1 out of 4 hospitalized COVID-19 patients require admission to an Intensive Care Unit (ICU) for respiratory support, and a large proportion of these ICU-COVID-19 patients, between 17% and 46%, have died. In these patients COVID-19 infection causes an inflammatory response in the lungs that can progress to inflammation with cytokine storm, Acute Lung Injury (ALI), Acute Respiratory Distress Syndrome (ARDS), thromboembolic events, disseminated intravascular coagulation, organ failure, and death. Mesenchymal Stem Cells (MSCs) are potent immunomodulatory cells that recognize sites of injury, limit effector T cell reactions, and positively modulate regulatory cell populations. MSCs also stimulate local tissue regeneration via paracrine effects inducing angiogenic, anti-fibrotic and remodeling responses. MSCs can be derived in large number from the Umbilical Cord (UC). UC-MSCs, utilized in the allogeneic setting, have demonstrated safety and efficacy in clinical trials for a number of disease conditions including inflammatory and immune-based diseases. UC-MSCs have been shown to inhibit inflammation and fibrosis in the lungs and have been utilized to treat patients with severe COVID-19 in pilot, uncontrolled clinical trials, that reported promising results. UC-MSCs processed at our facility have been authorized by the FDA for clinical trials in patients with an Alzheimer's Disease, and in patients with Type 1 Diabetes (T1D). We hypothesize that UC-MSC will also exert beneficial therapeutic effects in COVID-19 patients with cytokine storm and ARDS. We propose an early phase controlled, randomized clinical trial in COVID-19 patients with ALI/ARDS. Subjects in the treatment group will be treated with two doses of UC-MSC (l00 × 106 cells). The first dose will be infused within 24 hours following study enrollment. A second dose will be administered 72 ± 6 hours after the first infusion. Subject in the control group will receive infusion of vehicle (DPBS supplemented with 1% HSA and 70 U/kg unfractionated Heparin, delivered IV) following the same timeline. Subjects will be evaluated daily during the first 6 days, then at 14, 28, 60, and 90 days following enrollment (see Schedule of Assessment for time window details). Safety will be determined by adverse events (AEs) and serious adverse events (SAEs) during the follow-up period. Efficacy will be defined by clinical outcomes, as well as a variety of pulmonary, biochemical and immunological tests. Success of the current study will provide a framework for larger controlled, randomized clinical trials and a means of accelerating a possible solution for this urgent but unmet medical need. The proposed early phase clinical trial will be performed at the University of Miami (UM), in the facilities of the Diabetes Research Institute (DRI), UHealth Intensive Care Unit (ICU) and the Clinical Translational Research Site (CTRS) at the University of Miami Miller School of Medicine and at the Jackson Memorial Hospital (JMH).

3.
Eur Rev Med Pharmacol Sci ; 23(17): 7568-7572, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31539148

ABSTRACT

OBJECTIVE: Our purpose was to compare quantitative CT-derived changes in lung fibrosis with pulmonary function, including DLCO, in human subjects with idiopathic pulmonary fibrosis who received an injection of one of two different intravenous doses of human bone-marrow-derived mesenchymal stem cells. PATIENTS AND METHODS: Two three-subject cohorts from the AETHER trial (Allogeneic Human Cells in subjects with Idiopathic Pulmonary Fibrosis via Intravenous Delivery) underwent high-resolution CT and clinical testing at baseline, 24 weeks, and 48 weeks after injection. Cohort 1 received 2x107 stem cells, and cohort 2 received 1x108 stem cells. CT scans were quantitatively analyzed for lung fibrosis using 510K cleared validated software. The percent predicted DLCO and other pulmonary function studies were obtained. RESULTS: The cohorts were well matched in lung fibrosis at baseline as assessed by CT scan and lung function. The mean QLF in cohort 1 increased from 13.1% at baseline to 17.1% at 48 weeks, while mean QLF in cohort 2 increased from 15.4% at baseline to 16.5% at 48 weeks. The subjects in cohort 2 progressed more slowly in whole lung fibrosis by a mean of 2.87% compared with cohort 1 (p=0.001 with adjustment of baseline covariates) during the baseline to the 48-week interval. The baseline DLCO was lower in cohort 2 than in cohort 1 (p<0.0001). Over 48 weeks of the study, cohort 2 subjects demonstrated a mean DLCO decline of only 2% compared with a decline of 17% in cohort 1 subjects (p=0.02). CONCLUSIONS: In this pilot study, the subjects receiving 1x108 stem cells demonstrated slower progression in quantitative lung fibrosis and a smaller decrease in DLCO than subjects receiving 2x107 stem cells.


Subject(s)
Carbon Monoxide/analysis , Idiopathic Pulmonary Fibrosis/pathology , Stem Cell Transplantation , Stem Cells/cytology , Administration, Intravenous , Cohort Studies , Disease Progression , Humans , Idiopathic Pulmonary Fibrosis/diagnostic imaging , Idiopathic Pulmonary Fibrosis/therapy , Lung/diagnostic imaging , Pilot Projects , Respiratory Function Tests , Stem Cells/metabolism , Tomography, X-Ray Computed , Treatment Outcome , Vital Capacity , Walk Test
4.
Oncogene ; 32(18): 2335-45, 2013 May 02.
Article in English | MEDLINE | ID: mdl-22733134

ABSTRACT

Considerable interest has been generated from the results of recent clinical trials using smoothened (SMO) antagonists to inhibit the growth of hedgehog (HH) signaling-dependent tumors. This interest is tempered by the discovery of SMO mutations mediating resistance, underscoring the rationale for developing therapeutic strategies that interrupt HH signaling at levels distinct from those inhibiting SMO function. Here, we demonstrate that HH-dependent non-small cell lung carcinoma (NSCLC) growth is sensitive to blockade of the HH pathway upstream of SMO, at the level of HH ligand processing. Individually, the use of different lentivirally delivered shRNA constructs targeting two functionally distinct HH-processing proteins, skinny hedgehog (SKN) or dispatched-1 (DISP-1), in NSCLC cell lines produced similar decreases in cell proliferation and increased cell death. Further, providing either an exogenous source of processed HH or a SMO agonist reverses these effects. The attenuation of HH processing, by knocking down either of these gene products, also abrogated tumor growth in mouse xenografts. Finally, we extended these findings to primary clinical specimens, showing that SKN is frequently overexpressed in NSCLC and that higher DISP-1 expression is associated with an unfavorable clinical outcome. Our results show a critical role for HH processing in HH-dependent tumors, identifies two potential druggable targets in the HH pathway, and suggest that similar therapeutic strategies could be explored to treat patients harboring HH ligand-dependent cancers.


Subject(s)
Acyltransferases/metabolism , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Hedgehog Proteins/metabolism , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Membrane Proteins/metabolism , Acyltransferases/genetics , Amino Acid Sequence , Animals , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/mortality , Cell Line, Tumor , Cell Survival , Hedgehog Proteins/genetics , Humans , Lung Neoplasms/genetics , Lung Neoplasms/mortality , Membrane Proteins/genetics , Mice , Mice, Transgenic , Molecular Sequence Data , Rabbits , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Signal Transduction/genetics , Smoothened Receptor , Xenograft Model Antitumor Assays
5.
J Appl Behav Anal ; 31(1): 131-4, 1998.
Article in English | MEDLINE | ID: mdl-9532757

ABSTRACT

We evaluated the contribution of spousal feedback to a parent education curriculum designed for parents of children with autism. A modified multiple baseline design across 3 husband-and-wife dyads was used to examine the effects of teaching parents to give each other feedback on their teaching performance. For 5 of 6 participants, improvement in teaching performance occurred following didactic presentations. However, additional improvement was observed for 5 participants when the spousal feedback component was implemented.


Subject(s)
Autistic Disorder/therapy , Behavior Therapy/economics , Feedback , Parents/education , Spouses/education , Autistic Disorder/economics , Autistic Disorder/psychology , Child, Preschool , Cost-Benefit Analysis , Curriculum , Female , Home Care Services/economics , Humans , Male
6.
Am J Physiol ; 272(5 Pt 1): L1021-4, 1997 May.
Article in English | MEDLINE | ID: mdl-9176269

ABSTRACT

The proliferation of airway smooth muscle cells is a characteristic feature of asthma. Endothelin (ET)-1, a member of a family of three isopeptides (ET-1, ET-2, and ET-3), functions as a spasmogen and mitogen for airway smooth muscle cells. Two types of ET receptors have been identified in mammalian species (ETA and ETB). Because the respective roles of ETA and ETB receptors in ET-1-induced mitogenesis are not known, we determined the effect of two selective ETA and ETB antagonists (BQ-610 and BQ-788) on ET-1-induced mitogenesis of cultured ovine airway smooth muscle cells. Both BQ-610 and BQ-788 inhibited ET-1-induced mitogenesis in a concentration-dependent manner, with BQ-788 exhibiting more potent antagonism [half-maximal inhibitory concentration (IC50) = 3.5 nM, slope of 0.49] compared with BQ-610 (IC50 = 20 nM, slope of 0.27). The combined ETA-ETB antagonist, bosentan, also inhibited ET-1-induced mitogenesis (IC50 = 20 nM, slope of 0.60). The effects of BQ-788 and bosentan appear to be mediated via the same receptor (ETB), as their slopes are comparable. These observations suggest that both receptor subtypes are utilized in ET-1-induced proliferation of ovine airway smooth muscle. ET receptor expression may be important in the increase in airway smooth muscle mass seen in the airways of patients with bronchial asthma.


Subject(s)
Endothelin-1/pharmacology , Mitogens/pharmacology , Muscle, Smooth/drug effects , Receptors, Endothelin/physiology , Trachea/drug effects , Animals , Bosentan , Cell Division/drug effects , Cells, Cultured , Endothelin Receptor Antagonists , Muscle, Smooth/cytology , Oligopeptides/pharmacology , Piperidines/pharmacology , Receptor, Endothelin A , Receptor, Endothelin B , Sheep , Sulfonamides/pharmacology , Trachea/cytology
7.
Am J Physiol ; 270(1 Pt 1): L54-61, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8772527

ABSTRACT

Airway smooth muscle tone and growth is regulated by endothelin-1 (ET-1), but the sources of ET-1 in the airway wall have not been clearly defined. We therefore wished to estimate the relative contributions of the epithelium and endothelium to ET-1 production in the bronchi (mean ID 1.7-4.9 mm) of mature normal sheep. Morphometric assessment of bronchial cross-sections revealed a number of epithelial cells three times greater than endothelial cells by direct cell count. In contrast, the overall cell surface density was five to six times greater, and the airway smooth muscle-centered cell surface density was three to four times greater for endothelial cells than for epithelial cells. The expression of preproendothelin-1 mRNA was detected in cultured aortic endothelial cells (as a substitute for bronchial endothelial cells) but not in cultured bronchial epithelial cells, and the former secreted seven times more immunoreactive ET-1 than the latter. These findings show that topographically the endothelium is better positioned for the regulation of ovine bronchial smooth muscle than the epithelium. Furthermore, the findings suggest greater constitutive ET-1 secretion by cultured endothelium than by epithelium.


Subject(s)
Bronchi/metabolism , Endothelin-1/metabolism , Animals , Aorta/cytology , Aorta/metabolism , Bronchi/cytology , Cells, Cultured , Endothelins/genetics , Endothelium/cytology , Endothelium/metabolism , Endothelium, Vascular/cytology , Endothelium, Vascular/metabolism , Epithelial Cells , Epithelium/metabolism , Female , Protein Precursors/genetics , RNA, Messenger/metabolism , Sheep
8.
Exp Lung Res ; 21(3): 453-68, 1995.
Article in English | MEDLINE | ID: mdl-7621780

ABSTRACT

Endothelin-1 (ET-1) has constrictor and mitogenic effects on airway smooth muscle strips and cultured cells, respectively. This study addresses the type of the ET receptor subtype(s) present on ovine airway smooth muscle cells and the possibility of autocrine effects. The expression of the preproendothelin-1 gene was demonstrated by Northern analysis, and the medium obtained from these cells contained immunoreactive-ET-1. Competitive binding experiments between [125I]ET-1 and ET-1, ET-3, and two ET-receptor subtype selective-ligands, BQ-123 (ETA) and sarafotoxin S6c (ETB), yielded IC50 values of 1.1 +/- 0.1, 227 +/- 13, 12 +/- 1, and 194 +/- 21 nM, respectively. ET-3 also gave a limited number of higher affinity sites. In the presence of BQ-123 (1 microM), the binding of [125I]ET-1 was decreased by 80-85%, and the IC50 values with ET-1, ET-3, and S6c were 2.0 +/- 0.4, 3.6 +/- 0.6, and 1.1 +/- 0.9 nM, respectively. In similar experiments with 0.1 microM sarafotoxin S6c, the respective IC50 values for ET-1 and ET-3 were 2.4 +/- 0.4 and 300 +/- 20 nM. These results demonstrate that about 85 +/- 5% of ET-1 binding to airway smooth muscle cells is to ETA receptors and that these cells produce ET-1 in vitro.


Subject(s)
Muscle, Smooth/metabolism , Pulmonary Alveoli/metabolism , Receptors, Endothelin/metabolism , Animals , Binding, Competitive , Blotting, Northern , Cells, Cultured , Endothelin-1 , Endothelins/biosynthesis , Endothelins/genetics , Endothelins/metabolism , Muscle, Smooth/cytology , Protein Precursors/genetics , Pulmonary Alveoli/cytology , RNA, Messenger/metabolism , Sheep
9.
Mol Cell Biochem ; 136(1): 91-6, 1994 Jul 13.
Article in English | MEDLINE | ID: mdl-7854336

ABSTRACT

We recently demonstrated that transformed murine Leydig cells (MA-10) responded to endothelin-1 (ET-1) via increased steroidogenesis. This study addresses the endothelin receptor subtype present on this cell line and whether or not the cells produce ET-1. The expression of the preproendothelin-1 (PPET-1) gene was investigated by Northern blot analysis, and PPET-1 mRNA was found to be < 0.2% of that present in pulmonary endothelial cells. The medium from MA-10 cells, maintained under serum-free conditions, was analyzed by radio-immunoassay to determine immunoreactive-ET-1 production and ET-1 levels were found to be below the sensitivity of the assay (< 10 pg/ml). The data from competitive binding experiments with [125I]ET-1 and unlabeled ET-1, ET-3 and receptor subtype selective ligands yielded a single class of high affinity binding sites with ETA receptor subtype characteristics. The results of this study demonstrate that MA-10 cells possess the ETA receptor subtype but do not produce significant quantities of ET-1 under basal conditions.


Subject(s)
Endothelins/pharmacology , Leydig Cells/metabolism , Neoplasm Proteins/biosynthesis , Receptors, Endothelin/biosynthesis , Animals , Binding, Competitive , Cell Line, Transformed , Culture Media, Conditioned , Culture Media, Serum-Free , Gene Expression Regulation, Neoplastic/drug effects , Leydig Cells/drug effects , Male , Mice , Neoplasm Proteins/genetics , RNA, Messenger/genetics , Receptors, Endothelin/classification , Receptors, Endothelin/genetics
10.
Fertil Steril ; 61(6): 1083-7, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8194621

ABSTRACT

OBJECTIVE: To determine the concentrations of immunoreactive (IR) endothelin-1 in human follicular fluid (FF) and whether IR-endothelin-1 levels are different in women with endometriosis-associated infertility. DESIGN: Follicular fluid and plasma samples, obtained from women with and without endometriosis undergoing IVF-ET, were collected at the time of oocyte aspiration and analyzed for IR-endothelin-1 levels. SETTING: Infertility clinic in an academic research environment. RESULTS: Overall, 90% of FF samples and 60% of plasma samples contained IR-endothelin-1 detectable above the threshold of assay sensitivity. Immunoreactive endothelin-1 levels (mean +/- SEM) in FF samples from women with and without endometriosis-associated infertility were 74 +/- 12 and 37 +/- 6 pg/mL, respectively. There was no difference in IR-endothelin-1 levels in FF samples between controlled ovarian hyperstimulation cycles with or without leuprolide acetate. No significant differences were detected in plasma IR-endothelin-1 levels in women with endometriosis-associated infertility when compared with those without. CONCLUSIONS: These results demonstrate the presence of IR-endothelin-1 in human FF obtained at the time of oocyte aspiration for IVF-ET and higher levels of IR-endothelin-1 in FF of women with endometriosis-associated infertility.


Subject(s)
Embryo Transfer , Endometriosis/metabolism , Endothelins/analysis , Endothelins/immunology , Fertilization in Vitro , Follicular Fluid/chemistry , Adult , Chromatography, High Pressure Liquid , Endometriosis/complications , Endothelins/metabolism , Female , Humans , Infertility, Female/etiology
11.
Am J Respir Cell Mol Biol ; 10(3): 316-21, 1994 Mar.
Article in English | MEDLINE | ID: mdl-7509612

ABSTRACT

Endothelin exists as three isoforms (ET-1, ET-2, and ET-3) and exhibits vasoconstricting, bronchoconstricting, and growth-promoting properties in vascular smooth muscle. In the airways, ET-1 immunoreactivity and mRNA have been detected and localized to the epithelium, smooth muscle, and endothelium in different species, including humans. It has been suggested that ET-1 may have a role in the airway smooth muscle hyperplasia and hypertrophy seen in patients with bronchial asthma. We studied ovine airway smooth muscle cells (SMC) in vitro and showed saturable binding of [125I]ET-1 with a dissociation constant (Kd) of 0.4 nM and high affinity binding sites (Bmax) for ET-1 (104 fmol/10(6) cells). This binding was functional as ET-1 promoted mitogenesis of these muscle cells as measured by increased cell number in the absence of serum. Twenty-four hours after exposing the cells to graded doses of ET-1 from 1 pM to 1 microM, cell number increased significantly over control in a dose-dependent manner. ET-1 also enhanced the transient expression of c-fos mRNA by 2.5-fold over control, with maximal expression occurring at 30 min. These observations provide evidence that: (1) airway SMC possess high affinity binding sites for ET-1, and (2) ET-1 is mitogenic for airway SMC as determined by increased cell number and amplification of c-fos mRNA expression. ET-1 may have a fundamental role in influencing the growth of smooth muscle in the airways.


Subject(s)
Endothelins/pharmacology , Mitogens/pharmacology , Muscle, Smooth/cytology , Trachea/cytology , Animals , Binding Sites , Cell Division/drug effects , Cells, Cultured , Endothelins/metabolism , Gene Expression/drug effects , Genes, fos , Muscle, Smooth/drug effects , Muscle, Smooth/metabolism , RNA, Messenger/metabolism , Sheep , Staining and Labeling , Trachea/drug effects , Trachea/metabolism
12.
Endocrinology ; 132(2): 598-603, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8425480

ABSTRACT

The effects of endothelin-1 (ET-1), a potent vasoconstrictor and mitogen to various cell types, on proliferation and differentiated functions of the murine Leydig tumor cell line MA-10 were investigated. Kinetic binding experiments at room temperature showed that [125I] ET-1 bound to MA-10 cells and reached equilibrium in 2 h. The data from competitive binding experiments yielded an apparent single class of high affinity binding sites characterized by a Kd and maximum binding capacity of 1 nM and 59 fmol/10(6) cells, respectively. For steroidogenic assays, cells were incubated with ET-1 (1 pM to 1 microM) and with epidermal growth factor (10 ng/ml) for 4 h at 37 C, and the progesterone levels in the medium were measured by RIA. Like epidermal growth factor, ET-1 caused about a 6-fold increase in progesterone production. ET-1 also enhanced the transient expression of the protooncogenes c-jun and c-myc by 3- and 2-fold, respectively. For proliferation studies, ET-1 (1 pM to 1 microM) was added to quiescent MA-10 cells for 24 h, and cell counts were performed; no increase in cell number was observed. The results of this study demonstrate that MA-10 cells possess high affinity binding sites for ET-1 and that ET-1 stimulates progesterone production and protooncogene expression, but not mitosis in this cell line.


Subject(s)
Endothelins/metabolism , Endothelins/pharmacology , Genes, jun/drug effects , Genes, myc/drug effects , Progesterone/biosynthesis , Receptors, Endothelin/metabolism , Animals , Blotting, Northern , Cell Line, Transformed , Dose-Response Relationship, Drug , Epidermal Growth Factor/pharmacology , Gene Expression/drug effects , Kinetics , Leydig Cell Tumor , Leydig Cells/drug effects , Leydig Cells/metabolism , Male , Mice , Tumor Cells, Cultured
13.
J Appl Physiol (1985) ; 72(5): 1681-6, 1992 May.
Article in English | MEDLINE | ID: mdl-1601772

ABSTRACT

The media from cultured microvascular and macrovascular endothelial cells (conditioned media, CM) were collected and tested for constrictor activity in sheep coronary artery rings and tracheal smooth muscle strips in vitro (isometric force), expressed as percentage of contraction produced by 80 mM KCl. Both microvascular (micro) and macrovascular (macro) CM caused a sustained slow-onset contraction (P less than 0.05) of the coronary artery rings by 71 +/- 10% (micro; n = 7) and 67 +/- 8% (macro; n = 6) and tracheal smooth muscle strips by 33 +/- 14% (micro; n = 6) and 34 +/- 6% (macro; n = 11); the calcium antagonist gallopamil (10(-7) M) attenuated these effects by 25-55%. Unconditioned medium and medium conditioned by cultured tracheal smooth muscle cells had no constrictor activity on coronary artery rings or tracheal smooth muscle strips. Synthetic endothelin (ET-1) also produced contraction of coronary artery rings and tracheal smooth muscle strips. The mean levels of ET-1 measured by radioimmunoassay were 1,200 pg/ml in the macro CM and 33 pg/ml in the micro CM. Depleting macro CM of ET-1 by affinity columns constructed with protein A agarose and anti-ET-1 antibody removed the contractile activity for coronary artery rings and tracheal smooth muscle strips. Thus ET-1 did not appear to be the contractile substance in the micro CM. Preliminary characterization of the contractile substance in micro CM revealed that it was heat stable, had a molecular weight of less than 10,000, was inactivated by trypsin, and retained its activity after two cycles of freeze-thawing.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Endothelins/biosynthesis , Endothelium, Vascular/metabolism , Vasoconstrictor Agents/metabolism , Animals , Cells, Cultured , Endothelins/metabolism , In Vitro Techniques , Muscle, Smooth/drug effects , Muscle, Smooth, Vascular/drug effects , Sheep , Trachea/drug effects , Vasoconstrictor Agents/isolation & purification , Vasoconstrictor Agents/pharmacology
14.
J Cardiovasc Pharmacol ; 13 Suppl 5: S57-62 discussion S74, 1989.
Article in English | MEDLINE | ID: mdl-2473329

ABSTRACT

The conditioned medium (CM) from microvascular and macrovascular endothelial cell (EC) cultures was tested for constrictor activity. Sheep coronary artery rings, under 1 g tension, and sheep tracheal smooth muscle strips, under 2 g tension, were hung in organ baths containing Krebs-Henseleit solution (39 degrees C) and were equilibrated with 95% O2 and 5% CO2. Isometric force was measured in response to 80 mM KCl and constrictor responses to 100% CM were expressed as a percentage of maximum KCl response. Serum-free CM from confluent microvascular endothelial cells caused a sustained, slow-onset contraction of the coronary rings similar to that obtained with CM from macrovascular ECs. Indomethacin (5 microM) added to either the microvascular or macrovascular CM enhanced the constrictor responses by 1.6- and 1.8-fold, respectively, and the constrictor effects of both media were reduced by the calcium antagonist gallopamil (10 nM). CM from macrovascular EC caused a sustained contraction of tracheal strips similar to microvascular CM. In both cases, constriction was preceded by a brief relaxation as noted in vascular smooth muscle. Unconditioned medium had no constrictor activity on either vascular or airway smooth muscle. Microvascular-derived constrictor activity was heat stable. There was a slight loss of activity in the heat-treated CM from the macrovascular cells compared with control CM. Constrictor effects on tracheal smooth muscle were partially reversed by 1 microM gallopamil.


Subject(s)
Microcirculation/metabolism , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth/drug effects , Peptides/pharmacology , Pulmonary Artery/metabolism , Animals , Cattle , Coronary Vessels/drug effects , Coronary Vessels/metabolism , Endothelins , Gallopamil/pharmacology , In Vitro Techniques , Muscle Contraction/drug effects , Peptide Biosynthesis , Trachea/drug effects , Trachea/metabolism
15.
In Vitro ; 18(10): 859-66, 1982 Oct.
Article in English | MEDLINE | ID: mdl-6816718

ABSTRACT

Cells derived from the endothelium of human iliac arteries were cultured in vivo. The cells were isolated, grown, and subcultured in HEPES buffered Medium 199 supplemented with 20% heat inactivated human whole blood serum, human alpha-thrombin, and commercial endothelial cell growth supplement derived from bovine brain. The cells were viable in culture for 8 to 10 passages at a split ratio of 1:3. After the 10th passage, the cells began to enlarge and their growth rate was reduced. No cultures were viable after the 12th passage. The cells were determined to be of endothelial origin by their morphology at confluence; their ultrastructural characteristics, including the presence of Weibel-Palade bodies; the production and release of factor VIII-related antigen; and by their maintenance of a surface that prevented platelet attachment. The cultured arterial endothelial cells released prostacyclin in response to challenge with thrombin and protamine sulfate but not in response to bradykinin or the platelet-derived growth factor. Although the cultures described in this report were derived from patients with varying degrees of atherosclerotic disease, there were no significant differences in morphological or physiological parameters among these cultures or in comparison with commonly studied cells derived from human umbilical veins.


Subject(s)
Iliac Artery/cytology , Antigens/metabolism , Cells, Cultured , Culture Media , Diabetes Mellitus/pathology , Endothelium/ultrastructure , Epoprostenol/metabolism , Factor VIII/immunology , Factor VIII/metabolism , Humans , Methods , Platelet Adhesiveness , von Willebrand Factor
16.
Cancer Res ; 41(11 Pt 1): 4466-70, 1981 Nov.
Article in English | MEDLINE | ID: mdl-6796261

ABSTRACT

The effect of reversible blood-brain barrier modification on the delivery of Adriamycin to the brain was studied in a rodent and canine model. Pharmacokinetic and physiological studies were done in these animals after a wide range of doses of Adriamycin (0.1 to 1.0 mg/kg) were administered into the carotid artery following osmotic barrier modification with mannitol. In the absence of barrier modification, no immunoreactive Adriamycin was detected in the cerebrum; whereas, following barrier modification, up to 4.5 micrograms of drug and/or metabolites per g of brain were found. Optimum tissue levels of Adriamycin and metabolites were achieved following barrier modification when the drug was administered by either bolus or slow continuous (15-min) infusion. Immunoreactive drug was identified in brain for up to 6 hr after administration. Significant functional neurotoxicity occurred at all dose levels, even at 0.1 mg/kg, a level at which Adriamycin concentration in the brain was below the level of detectability. Neuropathological examination revealed the presence of necrosis and hemorrhagic infarcts. Thus, these pharmacological and toxicity studies suggest that Adriamycin (or its metabolites) may produce significant clinical neurotoxicity when even small amounts penetrate the blood-brain barrier.


Subject(s)
Blood-Brain Barrier/drug effects , Brain/drug effects , Doxorubicin/toxicity , Animals , Brain/metabolism , Brain/pathology , Carotid Artery, Internal , Dogs , Doxorubicin/administration & dosage , Doxorubicin/analysis , Injections, Intra-Arterial , Kinetics , Mannitol/pharmacology , Models, Biological , Necrosis , Rats , Seizures/chemically induced
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