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1.
Public Health ; 196: 117-123, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34182257

ABSTRACT

OBJECTIVES: Persons experiencing homelessness (PEH) are known to be often excluded from primary health care and community prevention programmes leading to high use of hospital emergency departments (EDs). This study aimed to identify demographic features, clinical characteristics and attendance outcomes of PEH presenting to ED. STUDY DESIGN: Analysis of routinely collected data set. METHODS: Clinical presentations and drug prescription data of PEH who presented a major ED in the West Midlands region of England from 2014 to 2019 were extracted and analysed using descriptive and inferential statistics. RESULTS: During the study period, 3271 of 596,198 presentations were made by PEH; 74% PEH attendees were male. Drug- and alcohol-related conditions, as well as pain and injury constituted the most frequent reasons for presentation, contributing to over half of all presentations. A significantly higher proportion of males (nĀ =Ā 481, 20.3%) presented with drug and alcohol problems than females (nĀ =Ā 93, 11.2%) (PĀ ≤Ā 0.001). However, pain was the primary reason for presentation for twice as many female patients (nĀ =Ā 189, 22.8%) compared with males (nĀ =Ā 305, 12.9%) (PĀ <Ā 0.001). Nearly one in five left the ED before being assessed and a total of 39 patients (1.2%) died in the ED and 785 (24.0%) required in-patient admissions to the same hospital. CONCLUSIONS: Drug, alcohol and pain including the need of opioid analgesics constituted the majority of presentations made by PEH in ED. The observed rate of death of PEH in ED is 12 times higher than the general population. A very high proportion of PEH also leave the ED before being treated. Future research should focus on strengthening community interventions, particularly to improve access to those at risk of dual diagnoses of substance misuse and mental health problems. Interventions involving multisector collaborations are needed to improve seamless discharge from ED and minimise repeat attendance. Gender differences in the nature of presentations and ED outcomes needs to be investigated further.


Subject(s)
Emergency Service, Hospital , Ill-Housed Persons , Female , Humans , Male , Patient Admission , Population Groups , Primary Health Care
2.
Dis Esophagus ; 30(4): 1-8, 2017 Apr 01.
Article in English | MEDLINE | ID: mdl-28375478

ABSTRACT

Intraoperative pyloric procedures are often performed during esophagectomies to reduce the rates of gastric conduit dysfunction. They include pyloroplasty (PP), pyloromyotomy (PM), and pylorus botulinum toxin type-A injections (BI). Despite these procedures, patients frequently warrant further endoscopic interventions. The aim of this study is to compare intraoperative pyloric procedures and the rates of postoperative endoscopic interventions following minimally invasive esophagectomy (MIE). We identified patients who underwent MIE for esophageal carcinoma and grouped them as 'None' (no intervention), 'PP', 'PM', or 'BI' based on intraoperative pyloric procedure type. The rates of endoscopic interventions for the first six postoperative months were compared. To adjust for variability due to MIE type, the rates of >1 interventions were compared using a zero-inflated Poisson regression analysis. Significance was established at P < 0.05. There were 146 patients who underwent an MIE for esophageal cancer from 2008 to 2015; 77.4% were three-hole MIE, and 22.6% were Ivor- Lewis MIE. BI was most frequent in Ivor-Lewis patients (63.5%), while PP was most frequent (46.9%) in three-hole patients. Postoperative endoscopic interventions occurred in 38 patients (26.0%). The BI group had the highest percentage of patients requiring a postoperative intervention (n = 13, 31.7%). After adjusting for higher rates of interventions in three-hole MIE patients, the BI and None groups had the lowest rates of >1 postoperative interventions. Our data did not show superiority of any pyloric intervention in preventing endoscopic interventions. The patients who received BI to the pylorus demonstrated a trend toward a greater likelihood of having a postoperative intervention. However when adjusted for type of MIE, the BI and None groups had lower rates of subsequent multiple interventions. Further research is needed to determine if the choice of intraoperative pyloric procedure type significantly affects quality of life, morbidity, and overall prognosis in these patients.


Subject(s)
Endoscopy, Gastrointestinal/methods , Esophagectomy/methods , Intraoperative Care/methods , Postoperative Care/methods , Pylorus/surgery , Adult , Aged , Aged, 80 and over , Esophagectomy/adverse effects , Female , Gastric Emptying , Humans , Intraoperative Care/adverse effects , Male , Middle Aged , Poisson Distribution , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Postoperative Complications/surgery , Postoperative Period , Regression Analysis , Retrospective Studies , Stomach Diseases/etiology , Stomach Diseases/prevention & control , Stomach Diseases/surgery , Treatment Outcome
3.
Behav Res Methods ; 48(2): 614-20, 2016 06.
Article in English | MEDLINE | ID: mdl-26092392

ABSTRACT

We have constructed and tested a custom-made magnetic-imaging-compatible visual projection system designed to project on a very wide visual field (~80Ā°). A standard projector was modified with a coupling lens, projecting images into the termination of an image fiber. The other termination of the fiber was placed in the 3-T scanner room with a projection lens, which projected the images relayed by the fiber onto a screen over the head coil, viewed by a participant wearing magnifying goggles. To validate the system, wide-field stimuli were presented in order to identify retinotopic visual areas. The results showed that this low-cost and versatile optical system may be a valuable tool to map visual areas in the brain that process peripheral receptive fields.


Subject(s)
Magnetic Resonance Imaging/instrumentation , Magnetic Resonance Imaging/methods , Photic Stimulation/instrumentation , Photic Stimulation/methods , Adult , Brain Mapping , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging/economics , Male , Middle Aged , Reproducibility of Results , Visual Fields
4.
Int J Immunopathol Pharmacol ; 26(3): 621-32, 2013.
Article in English | MEDLINE | ID: mdl-24067459

ABSTRACT

Osteosarcoma is the most common primary malignant tumour of the bone. Although new therapies continue to be reported, osteosarcoma-related morbidity and mortality remain high. Modern medicine has greatly increased knowledge of the physiopathology of this neoplasm. Novel targets for drug development may be identified through an understanding of the normal molecular processes that are deeply modified in pathological conditions. The aim of the present study is to investigate, by immunohistochemistry, the localisation of different growth factors and of the proliferative marker Ki-67 in order to determine whether these factors are involved in the transformation of osteogenic cells and in the development of human osteosarcoma. We observed a general positivity for NGF - TrKA - NT3 - TrKC - VEGF in the cytoplasm of neoplastic cells and a strong expression for NT4 in the nuclear compartment. TGF-beta was strongly expressed in the extracellular matrix and vascular endothelium. BDNF and TrKB showed a strong immunolabeling in the extracellular matrix. Ki-67/MIB-1 was moderately expressed in the nucleus of neoplastic cells. We believe that these growth factors may be considered potential therapeutic targets in the treatment of osteosarcoma, although proof of this hypothesis requires further investigation.


Subject(s)
Bone Neoplasms/metabolism , Cell Proliferation , Endothelial Cells/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Osteosarcoma/metabolism , Receptors, Growth Factor/metabolism , Antineoplastic Agents/therapeutic use , Bone Neoplasms/blood supply , Bone Neoplasms/drug therapy , Bone Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Design , Endothelial Cells/drug effects , Endothelial Cells/pathology , Fluorescent Antibody Technique , Humans , Immunohistochemistry , Ki-67 Antigen/metabolism , Molecular Targeted Therapy , Osteosarcoma/blood supply , Osteosarcoma/drug therapy , Osteosarcoma/pathology , Receptors, Growth Factor/drug effects , Signal Transduction
5.
Clin Toxicol (Phila) ; 60(10): 1094-1098, 2022 10.
Article in English | MEDLINE | ID: mdl-35943421

ABSTRACT

OBJECTIVE: Synthetic cannabinoid receptor agonists (SCRA) are commonly encountered new psychoactive substances. Here we report the recent detection of ADB-BUTINACA in samples from patients attending United Kingdom emergency departments with toxicity after suspected drug misuse and describe the associated clinical features. METHODS: Consenting adults (≥16 y) presenting to participating hospitals with toxicity after suspected drug misuse have been included in the Identification Of Novel psychoActive substances (IONA) study since March 2015. Demographic and clinical features are recorded and blood and/or urine samples analysed using high-resolution accurate mass liquid chromatography-mass spectrometry. RESULTS: By December 2021, analytical data were available for 1279 IONA participants and ADB-BUTINACA was detected in at least one sample from 10 (9 males, age range 16-51 median 45 years), all presenting since February 2021. Smoking 'spice' was reported by four patients, two had ingested edible "cannabis" gums and four reported heroin use (2 intravenous, 1 smoked, 1 route not known). Co-use of pregabalin (oral) and crack cocaine (smoked) were also reported. In 3 cases ADB-BUTINACA was the only substance detected, while in seven other substances of misuse were also detected including other SCRA, opioids, benzodiazepines cocaine and pregabalin. Clinical features reported in these 2 groups respectively included reduced level of consciousness (3/3, 6/7), agitation (0/3, 4/7), tachycardia (0/3, 3/7), seizures (1/3, 1/7), hallucinations (1/3, 1/7), hypotension (1/3, 1/7). Metabolic acidosis (1/3, 0/7) and respiratory acidosis (1/3, 0/7), All 10 patients recovered with supportive care, including intubation and ventilation for one case. The median length of hospital stay was 19 h (range 2.6-131 h). CONCLUSIONS: ADB-BUTINACA has recently emerged as a drug of misuse in England. Clinical features of toxicity are consistent with those of other SCRA and include reduced level of consciousness, respiratory and/or metabolic acidosis, seizures, confusion and hallucinations.


Subject(s)
Cannabinoid Receptor Agonists , Crack Cocaine , Adult , Male , Humans , Adolescent , Young Adult , Middle Aged , Heroin , Pregabalin , Emergency Service, Hospital , England/epidemiology , Hallucinations , Benzodiazepines , Seizures
6.
Food Chem Toxicol ; 158: 112608, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34656697

ABSTRACT

Methylglyoxal (MG), a potent glycotoxin that can be found in the diet, is one of the main precursors of Advanced glycation end products (AGEs). It is well known that modifications in lifestyle such as nutritional interventions can be of great value for preventing brain deterioration. This study aimed to evaluate in vivo how an oral MG treatment, that mimics a high MG dietary intake, could affect brain health. From our results, we demonstrated that MG administration affected working memory, and induced neuroinflammation and oxidative stress by modulating the Receptor for Advanced glycation end products (RAGE). The gene and protein expressions of RAGE were increased in the hippocampus of MG mice, an area where the activity of glyoxalase 1, one of the main enzymes involved in MG detoxification, was found reduced. Furthermore, at hippocampus level, MG mice showed increased expression of proinflammatory cytokines and increased activities of NADPH oxidase and catalase. MG administration also increased the gene and protein expressions of Presenilin-1, a subunit of the gamma-secretase protein complex linked to Alzheimer's disease. These findings suggest that high MG oral intake induces alteration directly in the brain and might establish an environment predisposing to AD-like pathological conditions.


Subject(s)
Brain/drug effects , Cognition/drug effects , Diet , Glycation End Products, Advanced/toxicity , Presenilin-1/metabolism , Pyruvaldehyde/toxicity , Receptor for Advanced Glycation End Products/metabolism , Aging , Alzheimer Disease/etiology , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Animals , Brain/metabolism , Catalase/metabolism , Cytokines/metabolism , Female , Hippocampus/drug effects , Hippocampus/metabolism , Inflammation/etiology , Inflammation/metabolism , Lactoylglutathione Lyase/metabolism , Male , Memory/drug effects , Mice , NADPH Oxidases/metabolism , Neuroinflammatory Diseases/etiology , Neuroinflammatory Diseases/metabolism , Neuroinflammatory Diseases/pathology , Oxidative Stress
7.
J Neurosci Methods ; 341: 108720, 2020 07 15.
Article in English | MEDLINE | ID: mdl-32416472

ABSTRACT

BACKGROUND: DNA methylation plays a relevant role in the regulation of gene transcription, but currently the exact quantification of transcription factors binding to methylated DNA is not being determined. The binding of the transcription factor cAMP response element-binding protein-1 to its cognate CpG containing motif is known to be impaired upon methylation. It thus represents a paradigmatic system to experimentally verify the validity of a new in vitro method to measure the role of methylation on DNA/transcription factors binding. METHOD: An AlphaScreenĀ® assay was developed to quantitatively measure the contribution of DNA CpG methylation on the interaction with transcription factors. The method was validated measuring the variation in affinity of cAMP response element-binding protein-1 and its recognition motif in human Brain-derived neurotrophic factor gene exon IV promoter as a function of CpG methylation. RESULTS: For the first time, a quantitative direct correlation between DNA methylation and transcription factors binding is reported showing a dramatic reduction in binding affinity between fully methylated and non-methylated DNA. COMPARISON WITH EXISTING METHODS: This methodology allows to directly measure DNA/transcription factors binding ability as a function of DNA methylation levels thus improving not quantitative methods available today. Moreover, it allows to work with purified proteins and oligonucleotides without need of chromatin. CONCLUSIONS: The present methodology is suggested as a new analytical tool for the quantitative determination of the effect of CpG methylation on the interaction of gene promoters with transcription factors regulating gene expression, a key epigenetic mechanism implicated in many physiological and pathological conditions.


Subject(s)
DNA Methylation , Epigenesis, Genetic , Chromatin Immunoprecipitation , Cyclic AMP Response Element-Binding Protein/genetics , Humans , Promoter Regions, Genetic , Protein Binding
8.
Water Res ; 42(3): 643-52, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17904611

ABSTRACT

This study investigated the sorption of paraquat and 2,4-D on polymerin, the humic acid-like fraction of olive mill wastewater. Effects of pH, contact time, initial concentration and sorbent dosage on the sorption of both herbicides were studied. The sorption mechanism of paraquat on polymerin was consistent with the ion exchange of this herbicide with Ca, Mg and K natively occurring in the sorbent; in contrast, 2,4-D was bound to polymerin by hydrogen bonding. Simulated wastewaters contaminated with paraquat were purified after three sorption cycles on polymerin renewed at each cycle, at a solid/liquid ratio of 0.5, whereas those containing 2,4-D showed a maximal residue removal of 44% after two sorption cycles at the same ratio. The possible application of this model to other water-soluble herbicides, as well as the possible exploitation of polymerin as a bio-filter for the decontamination of pollution point sources is briefly discussed.


Subject(s)
2,4-Dichlorophenoxyacetic Acid/chemistry , Herbicides/chemistry , Industrial Waste , Olea , Paraquat/chemistry , Polymers/chemistry , Water Pollutants, Chemical/chemistry , Adsorption , Food-Processing Industry , Waste Disposal, Fluid/methods , Water Purification/methods
9.
J Hum Hypertens ; 31(4): 253-257, 2017 04.
Article in English | MEDLINE | ID: mdl-27629242

ABSTRACT

Poor adherence with pharmacotherapy is well recognised as one of the main barriers to achieving satisfactory blood pressure control, although accurately measuring patient adherence has historically been very challenging. Urine analysis by high-performance liquid chromatography-tandem mass spectrometry has recently become routinely available as a method of screening for non-adherence. In addition to measuring rates of adherence in hypertensive patients, this study aimed to investigate the reasons for non-adherence given by patients and how patients react when they are informed of their results. This was a retrospective observational study looking at results from the routine use of this assay in a specialist hypertension clinic in Birmingham, UK, in patients with uncontrolled hypertension and those under consideration for renal denervation. Out of the 131 patients analysed, only 67 (51%) were taking all their medications as prescribed. Forty-three patients (33%) were taking some of their medications, whilst 21 patients (16%) were completely non-adherent. The most common reasons cited for non-adherence were adverse effects of medication and forgetfulness. Adherence rates for thiazide/thiazide-like diuretics and spironolactone were lower than for other classes of antihypertensive drug. Despite the objective nature and high sensitivity of the test, 36% of non-adherent patients disputed the results. A minority of patients did not attend follow-up. Further research investigating the implications of a 'non-adherence' result on the patient-clinician relationship is required.


Subject(s)
Antihypertensive Agents/urine , Hypertension/drug therapy , Medication Adherence/statistics & numerical data , Antihypertensive Agents/therapeutic use , Humans , Medication Adherence/psychology , Retrospective Studies
11.
Cancer Res ; 55(1): 90-5, 1995 Jan 01.
Article in English | MEDLINE | ID: mdl-7805047

ABSTRACT

The receptors for urokinase plasminogen activator were studied in both normal human fibroblasts (WI-38 cells) and their SV40-transformed counterpart (VA-13 cells). We have shown that transformed cells expose 10 times more urokinase plasminogen activator receptors (u-PAR) than normal cells. By cross-linking aliquots of cell lysates with the aminoterminal fragment of the A chain of u-PA, containing the receptor-binding sequence, we have observed a u-PAR concentration at focal contacts in both cell lines. Only transformed cells were able to efficiently invade the basement membrane Matrigel. Switching off the receptor gene expression by the anti-messenger oligodeoxynucleotides strategy abolished the invasive properties of transformed cells. The anti-messenger oligodeoxynucleotide sequence we have designed inhibited the u-PAR gene expression, lowering both the receptor and the receptor mRNA. This indicates that overexpression of u-PAR gene is itself responsible for invasivity of transformed fibroblasts in our cell model system and that antisense compound therapy may prove to be of clinical interest in the control of cancer spreading.


Subject(s)
Neoplasm Invasiveness , Oligonucleotides, Antisense/pharmacology , Receptors, Cell Surface/metabolism , Base Sequence , Cell Transformation, Viral , Cells, Cultured , Fibroblasts , Humans , Molecular Sequence Data , Plasminogen Activators/metabolism , Receptors, Urokinase Plasminogen Activator , Simian virus 40 , Urokinase-Type Plasminogen Activator/metabolism
12.
J Neuroimmunol ; 294: 32-40, 2016 05 15.
Article in English | MEDLINE | ID: mdl-27138096

ABSTRACT

The development of multiple sclerosis, a major neurodegenerative disease, is due to both genetic and environmental factors that might trigger aberrant epigenetic changes of the genome. In this study, we analysed global DNA methylation in the brain of mice upon induction of experimental autoimmune encephalomyelitis (EAE), and the effect of environmental enrichment (EE). We demonstrate that global DNA methylation decreased in the striatum, but not in the cortex, of EAE mice compared to healthy controls, in particular in neuronal nitric oxide synthase (nNOS)-positive interneurons of this brain area. Also, in the striatum but again not in the cortex, decreased DNA methylation of the nNOS downstream effector, dexamethasone-induced Ras protein 1 (Dexras 1), was observed in EAE mice, and was paralleled by an increase in its mRNA. Interestingly, EE was able to revert EAE effects on mRNA expression and DNA methylation levels of Dexras 1 and reduced gene expression of nNOS and 5-lipoxygenase (Alox5). Conversely, interleukin-1Ɵ (IL-1Ɵ) gene expression was found up-regulated in EAE mice compared to controls and was not affected by EE. Taken together, these data demonstrate an unprecedented epigenetic modulation of nNOS-signaling in the pathogenesis of multiple sclerosis, and show that EE can specifically revert EAE effects on Dexras 1 along this pathway.


Subject(s)
Brain/metabolism , Encephalomyelitis, Autoimmune, Experimental/pathology , Epigenesis, Genetic/physiology , Nitric Oxide Synthase Type I/metabolism , Signal Transduction/physiology , ras Proteins/metabolism , 5-Methylcytosine/metabolism , Animals , Anti-Inflammatory Agents/pharmacology , Arachidonate 5-Lipoxygenase/metabolism , Brain/drug effects , Brain/pathology , Cytokines/genetics , Cytokines/metabolism , Dexamethasone/pharmacology , Disease Models, Animal , Dopamine and cAMP-Regulated Phosphoprotein 32/metabolism , Encephalomyelitis, Autoimmune, Experimental/immunology , Encephalomyelitis, Autoimmune, Experimental/metabolism , Epigenesis, Genetic/drug effects , Female , Mice , Mice, Inbred C57BL , Myelin-Oligodendrocyte Glycoprotein/immunology , Neurons/metabolism , Peptide Fragments/immunology , Signal Transduction/drug effects , ras Proteins/genetics
13.
Biochim Biophys Acta ; 885(3): 301-8, 1986 Mar 14.
Article in English | MEDLINE | ID: mdl-3004604

ABSTRACT

We have found the existence of specific receptors for the plasminogen activator, urokinase, in A431 human epidermoid carcinoma cells, cultures in plasminogen-free conditions. Two subsets of receptors have been recognized on the basis of 125I-labelled urokinase binding analysis: about 1 X 10(3) high-affinity (Kd = 5.0 X 10(-11) M) and 1 X 10(5) low-affinity (Kd = 9 X 10(-9) M) receptors per cell. The electron microscopic observation of a urokinase: ferritin conjugate has shown single and clustered receptors at the cell surface. Down-regulation of the receptors (T1/2 = 3.77 h) follows the binding of urokinase. The binding does not involve an intact catalytic site and is inhibited by a monoclonal antibody against the Mr 17500 proteolytic fragment of the A chain of urokinase.


Subject(s)
Receptors, Cell Surface/metabolism , Urokinase-Type Plasminogen Activator/metabolism , Amyloid beta-Protein Precursor , Antibodies, Monoclonal , Benzamidines/pharmacology , Carcinoma, Squamous Cell , Carrier Proteins/pharmacology , Cell Line , Cell Membrane/metabolism , Humans , Microscopy, Electron , Molecular Weight , Protease Nexins , Receptors, Urokinase Plasminogen Activator , Urokinase-Type Plasminogen Activator/immunology
14.
J Invest Dermatol ; 94(3): 310-6, 1990 Mar.
Article in English | MEDLINE | ID: mdl-2155272

ABSTRACT

On the basis of both 125I-labeled plasminogen activator binding analysis and transmission electron microscopy studies of the interaction of a plasminogen activator/gold complex with cell membranes, we have found that human keratinocytes have specific receptors for human urokinase-type plasminogen activator distributed on the cell surface as singlets, or as small or large clusters. The use in binding experiments of the purified A chain of urokinase-plasminogen activator and of anti-A chain monoclonal antibodies has indicated that cell receptors are specific for a sequence present on the A chain, as previously reported for other cells. The interaction of both the native molecule and the purified A chain with such receptors stimulates mobilization of keratinocytes in an in vitro cell model system (Boyden chamber), when present in the lower compartment of the migration apparatus in nanomolar concentrations. Preincubation of chemoattractants with a monoclonal antibody which prevents receptor/ligand interaction also prevents plasminogen activator-induced cell migration. These data suggest that, under the conditions used in this in vitro model system, the plasminogen activator-dependent mobilization of keratinocytes depends on the interaction of the ligand with free receptors on the cell surface, and is independent of plasmin generation.


Subject(s)
Keratinocytes/physiology , Receptors, Cell Surface/physiology , Urokinase-Type Plasminogen Activator/pharmacology , Antibodies, Monoclonal/immunology , Cell Movement/drug effects , Epidermal Cells , Epidermis/metabolism , Humans , Keratinocytes/drug effects , Keratinocytes/metabolism , Receptors, Urokinase Plasminogen Activator , Urokinase-Type Plasminogen Activator/immunology
15.
Endocrinology ; 132(2): 806-14, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8425495

ABSTRACT

Western blot analyses of the rat pituitary have detected a 22K PRL variant distinct from intact PRL (25K). We recently reported that glandular kallikrein (GK), an estrogen-induced lactotroph protease, can process PRL in vitro from a 25K form to a 22K form in a thiol-dependent cleavage at Arg174-Arg175 to remove 23 amino acids. We also detected an estrogen- and thiol-induced 22K PRL variant in the rat pituitary comigrating with a PRL product generated by in vitro processing with GK and carboxypeptidase-B. This study addressed whether the in vivo 22K PRL variant originates through a GK-like cleavage and is a regulated secretory product of the rat pituitary. A polyclonal antipeptide antiserum was raised against a synthetic peptide [PRL-(163-173)] representing the new C-terminus after GK and carboxypeptidase-B processing. In slot and Western blots, this antiserum (CT-antiserum) specifically recognized PRL processed in vitro by GK and carboxypeptidase-B and did not recognize intact PRL or PRL cleaved by GK alone. Western blot analysis of rat pituitary extracts with CT-antiserum specifically detected an estrogen- and thiol-induced 22K band that comigrated with a PRL product generated by in vitro processing with GK and carboxypeptidase-B. This 22K band was concentrated in subcellular fractions of the pituitary enriched in secretory granules. During short term incubations in medium 199, pituitaries from normal adult female rats released substantial amounts of 22K PRL; in contrast, male pituitaries did not release detectable 22K PRL. The release of 22K PRL from female pituitaries was powerfully blocked by bromocriptine, a dopaminergic agonist. GK was also released from pituitaries of female, but not male, rats, and GK release was inhibited by bromocriptine. The results identify the 22K PRL variant as PRL-(1-173), which is consistent with GK-like processing at Arg174-Arg175, followed by carboxypeptidase-B-like processing. The results also show that 22K PRL is a natural female-specific secretory product of the rat pituitary under inhibitory dopaminergic control.


Subject(s)
Cytoplasmic Granules/metabolism , Genetic Variation , Pituitary Gland, Anterior/metabolism , Prolactin/metabolism , Amino Acid Sequence , Animals , Blotting, Western , Bromocriptine/pharmacology , Cysteamine/pharmacology , Diethylstilbestrol/pharmacology , Female , Immune Sera , In Vitro Techniques , Kallikreins/metabolism , Male , Molecular Sequence Data , Molecular Weight , Oligopeptides/chemical synthesis , Oligopeptides/immunology , Organelles/drug effects , Organelles/metabolism , Ovariectomy , Pituitary Gland, Anterior/drug effects , Prolactin/analysis , Prolactin/genetics , Protein Processing, Post-Translational , Rats , Tissue Kallikreins , Trypsin/pharmacology
16.
Hypertension ; 25(4 Pt 2): 752-7, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7721428

ABSTRACT

We examined the regulatory influence of nitric oxide on development of calcium- and protein kinase C-dependent basal tone in rings of thoracic aortas from rats with aortic coarctation-induced hypertension and from normotensive controls. Aortic rings from hypertensive rats but not those from normotensive rats, bathed in Krebs' bicarbonate buffer and subjected to 2 g of passive stretch, were relaxed by removal of calcium from the buffer and by the protein kinase C inhibitors staurosporine and calphostin C. Protein kinase C activity was much greater in homogenates of aortae from hypertensive rats than in those from normotensive controls (2124 +/- 785 versus 608 +/- 73 pmol.min-1.mg protein-1, respectively). Relaxant responses to removal of calcium and to staurosporine were greater in aortic rings rubbed to remove the vascular endothelium than in endothelium-intact rings (-1.07 +/- 0.12 versus -0.70 +/- 0.10 g tension/mg tissue, respectively, for calcium removal and -1.10 +/- 0.12 versus -0.65 +/- 0.08 g tension/mg tissue, respectively, for staurosporine). Treatment with an inhibitor of nitric oxide synthesis increased calcium-dependent tone in both intact and endothelium-denuded aortic rings from hypertensive rats. Conversely, the administration of sodium nitroprusside or L-arginine reversed tone in both intact and denuded aortic rings from hypertensive rats, but acetylcholine reversed tone only in intact rings. The relaxant effects of these agents were paralleled by increases in cyclic guanosine monophosphate in aortic tissue. We conclude that aortic rings from rats with aortic coarctation-induced hypertension display calcium-dependent, protein kinase C-mediated tone in the absence of exogenous vasoconstrictors.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Aorta/physiopathology , Calcium/physiology , Hypertension/physiopathology , Protein Kinase C/physiology , Vasomotor System/physiopathology , Acetylcholine/pharmacology , Animals , Arginine/pharmacology , Cyclic GMP/metabolism , In Vitro Techniques , Male , Nitroprusside/pharmacology , Rats , Rats, Sprague-Dawley , Vasomotor System/drug effects
17.
Hypertension ; 27(1): 19-24, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8591882

ABSTRACT

We investigated the contribution of nitric oxide to the short-term blood pressure reduction caused by interruption of the renin-angiotensin system in angiotensin-dependent hypertension. The blood pressure of rats made hypertensive by coarctation of the aorta between the renal arteries at their origin fell after administration of the angiotensin-converting enzyme inhibitor ramiprilat (2 mg/kg IV; -75 +/- 5 mm Hg) or the angiotensin II antagonist losartan (30 mg/kg IV; -79 +/- 6 mm Hg). But the antihypertensive effect of these agents was attenuated in rats pretreated with NG-nitro-L-arginine methyl ester (10 mg/kg IV) to inhibit nitric oxide synthesis (ramiprilat, -23 +/- 7 mm Hg; losartan, -37 +/- 5 mm Hg). In rats made hypertensive by long-term infusion of angiotensin II (60 ng/min IV, 6 to 7 days), the vasodepressor response to discontinuation of the angiotensin II infusion also was attenuated by pretreatment with the nitric oxide synthesis inhibitor (-52 +/- 7 versus -31 +/- 7 mm Hg); this attenuation was not demonstrable in rats receiving sodium nitroprusside (1 microgram.kg-1.min-1 IV) to replace the loss of endogenous nitric oxide (-72 +/- 9 mm Hg). Pretreatment with NG-nitro-L-arginine methyl ester did not interfere with the vasodepressor effect of sodium nitroprusside or prazosin in rats with aortic coarctation-induced hypertension or with the blood pressure reduction caused by discontinuation of an infusion of phenylephrine in rats made hypertensive by long-term administration of this drug. These data suggest a contribution of nitric oxide to the blood pressure reduction caused by interruption of the renin-angiotensin system in models of established angiotensin-dependent hypertension.


Subject(s)
Angiotensin II/antagonists & inhibitors , Blood Pressure/drug effects , Hypertension/physiopathology , Nitric Oxide/physiology , Angiotensin II/administration & dosage , Angiotensin II/pharmacology , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Animals , Aortic Coarctation/complications , Arginine/analogs & derivatives , Arginine/pharmacology , Biphenyl Compounds/pharmacology , Hypertension/chemically induced , Hypertension/etiology , Imidazoles/pharmacology , Losartan , Male , NG-Nitroarginine Methyl Ester , Nitric Oxide Synthase/antagonists & inhibitors , Ramipril/analogs & derivatives , Ramipril/pharmacology , Rats , Rats, Sprague-Dawley , Renin/blood , Tetrazoles/pharmacology , Vasoconstrictor Agents/pharmacology
18.
Hypertension ; 23(6 Pt 1): 744-51, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8206572

ABSTRACT

We contrasted in normotensive and hypertensive rats the effect of inhibition of nitric oxide synthesis on isometric tension development by aortic rings bathed in Krebs' bicarbonate buffer. NG-Nitro-L-arginine methyl ester (L-NAME) (3 x 10(-4) mol/L) increased tension (82 +/- 11% of the response to 120 mmol/L potassium chloride) in rings of thoracic aorta taken from hypertensive rats 7 to 14 days after aortic coarctation, whereas rings of abdominal aorta from below the coarctation were unresponsive, as were rings of thoracic aorta from rats with deoxycorticosterone-salt-induced hypertension and from the corresponding normotensive controls of either model of hypertension. The contractile response to L-NAME in aortic rings of rats with aortic coarctation was reversed by L-arginine (1 mmol/L), attenuated by removal of the endothelium, and blunted by the protein kinase C inhibitor staurosporine but was unaffected by inhibition of cyclooxygenase, scavengers of superoxide anion, or blockade of receptors for angiotensin, norepinephrine, serotonin, or endothelin. In additional experiments we contrasted the effect of L-NAME (10 mg/kg IV) on the blood pressure of sham-operated rats and rats with aortic coarctation after pretreatment of animals in both groups with DuP 753 (30 mg/kg IV) to achieve blood pressure equalization. The pressor response to L-NAME was twofold greater in rats with aortic coarctation than in sham-operated controls. That pressor and aortic constrictor responsiveness to L-NAME are increased after aortic coarctation suggests that a mechanism of vasodilation, mediated by nitric oxide, is preferentially manifested in rats with aortic coarctation-induced hypertension.


Subject(s)
Aorta, Thoracic/physiology , Hypertension/physiopathology , Nitric Oxide/antagonists & inhibitors , Animals , Antihypertensive Agents/pharmacology , Aorta, Thoracic/drug effects , Aortic Coarctation/complications , Arginine/analogs & derivatives , Arginine/pharmacology , Biphenyl Compounds/pharmacology , Blood Pressure/drug effects , Hypertension/etiology , Imidazoles/pharmacology , In Vitro Techniques , Losartan , Male , Methylene Blue/pharmacology , NG-Nitroarginine Methyl Ester , Phenylephrine/pharmacology , Rats , Rats, Sprague-Dawley , Tetrazoles/pharmacology , Vasoconstriction/drug effects
19.
Gene ; 171(1): 9-17, 1996 May 24.
Article in English | MEDLINE | ID: mdl-8675038

ABSTRACT

A striking feature of recent outbreaks of vancomycin-resistant (VmR) enterococci is the apparent horizontal dissemination of resistance determinants. The plasmids pHKK702 and pHKK703 from Enterococcus faecium clinical isolate R7 have been implicated in the conjugal transfer of VmR. pHKK702 is a 41-kb plasmid that contains an element indistinguishable from the glycopeptide-resistance transposon Tn1546. pHKK703 is an approx. 55-kb putative sex pheromone-response plasmid that is required for conjugative mobilization of pHKK702. During experiments in which strain R7 was used as a donor, a highly conjugative VmR transconjugant was isolated that formed constitutive cellular aggregates. Restriction analyses and DNA hybridizations revealed that the transconjugant harbored a single plasmid of approx. 92 kb and this plasmid (pHKK701) was composed of DNA from both pHKK702 and pHKK703. Results from DNA sequence analyses showed that a 39-kb composite transposon (Tn5506) from pHKK702 had inserted into pHKK703. The left end of Tn5506 contained a single insertion sequence (IS) element, IS1216V2, whereas the right end was composed of a tandem IS structure consisting of the novel 1065-bp IS1252 nested within an IS1216V1 element. Transposition of Tn5506 from pHKK702 to pHKK703 created an 8-bp target sequence duplication at the site of insertion and interrupted an ORF (ORFX) that was 91% identical to that of prgX, a gene proposed to negatively regulate sex pheromone response of the E.faecalis plasmid, pCF10. We propose that the interruption of ORFX by Tn5506 led to the constitutive cellular aggregation phenotype and thereby enhanced the efficiency with which VmR was transferred. Similar IS1216V-mediated transposition events may contribute to the horizontal spread of glycopeptide resistance among enterococci in nature.


Subject(s)
Anti-Bacterial Agents/pharmacology , Conjugation, Genetic/genetics , Enterococcus faecium/drug effects , Plasmids/genetics , Vancomycin/pharmacology , Amino Acid Sequence , Bacterial Adhesion/genetics , Bacterial Proteins/genetics , Base Sequence , DNA Transposable Elements/genetics , Drug Resistance, Microbial/genetics , Enterococcus faecium/genetics , Molecular Sequence Data , Open Reading Frames/genetics , Replicon/genetics , Sex Attractants/genetics
20.
Drugs ; 35 Suppl 1: 9-14, 1988.
Article in English | MEDLINE | ID: mdl-3129275

ABSTRACT

Treatment with tiaprofenic acid appreciably reduced the level of plasminogen activators in the medium of 3T3-Balb mouse fibroblasts, as revealed by both a fibrin plate assay and amidolytic determination with chromogenic substrates. At the same time, tiaprofenic acid was able to inhibit the production of plasminogen activators induced by phorbol myristate acetate, a powerful inflammation and tumour promoter, added to the cell monolayers. By isolating the inhibitors of plasminogen activators it was possible to show that the decrease of fibrinolytic activity produced by tiaprofenic acid is not related to an increase of inhibitors. Rather, a decrease of activators seems to take place. Synovial fluid samples from 4 patients before and after treatment with tiaprofenic acid were also assayed for plasminogen activator activity by the fibrin lysis method. In 3 of the 4 cases a marked decrease after treatment was evident. The one unresponsive patient suffered from a para-neoplastic arthritis.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Inflammation/metabolism , Plasminogen Activators/metabolism , Propionates/pharmacology , Animals , Arthritis, Rheumatoid/metabolism , Cells, Cultured , Chromatography, Affinity , Mice , Mice, Inbred BALB C , Plasminogen Activators/antagonists & inhibitors , Plasminogen Inactivators , Synovial Fluid/metabolism
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