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1.
JCO Glob Oncol ; 6: 486-499, 2020 03.
Article in English | MEDLINE | ID: mdl-32213095

ABSTRACT

PURPOSE: Head and neck squamous cell carcinoma (HNSCC) incidence is high in South America, where recent data on survival are sparse. We investigated the main predictors of HNSCC survival in Brazil, Argentina, Uruguay, and Colombia. METHODS: Sociodemographic and lifestyle information was obtained from standardized interviews, and clinicopathologic data were extracted from medical records and pathologic reports. The Kaplan-Meier method and Cox regression were used for statistical analyses. RESULTS: Of 1,463 patients, 378 had a larynx cancer (LC), 78 hypopharynx cancer (HC), 599 oral cavity cancer (OC), and 408 oropharynx cancer (OPC). Most patients (55.5%) were diagnosed with stage IV disease, ranging from 47.6% for LC to 70.8% for OPC. Three-year survival rates were 56.0% for LC, 54.7% for OC, 48.0% for OPC, and 37.8% for HC. In multivariable models, patients with stage IV disease had approximately 7.6 (LC/HC), 11.7 (OC), and 3.5 (OPC) times higher mortality than patients with stage I disease. Current and former drinkers with LC or HC had approximately 2 times higher mortality than never-drinkers. In addition, older age at diagnosis was independently associated with worse survival for all sites. In a subset analysis of 198 patients with OPC with available human papillomavirus (HPV) type 16 data, those with HPV-unrelated OPC had a significantly worse 3-year survival compared with those with HPV-related OPC (44.6% v 75.6%, respectively), corresponding to a 3.4 times higher mortality. CONCLUSION: Late stage at diagnosis was the strongest predictor of lower HNSCC survival. Early cancer detection and reduction of harmful alcohol use are fundamental to decrease the high burden of HNSCC in South America.


Subject(s)
Head and Neck Neoplasms , Aged , Argentina , Brazil/epidemiology , Colombia , Head and Neck Neoplasms/epidemiology , Humans , Squamous Cell Carcinoma of Head and Neck/epidemiology , Uruguay
2.
Mol Psychiatry ; 23(9): 1900-1910, 2018 09.
Article in English | MEDLINE | ID: mdl-28848234

ABSTRACT

Alcohol use disorder (AUD) is a common and chronic disorder with substantial effects on personal and public health. The underlying pathophysiology is poorly understood but strong evidence suggests significant roles of both genetic and epigenetic components. Given that alcohol affects many organ systems, we performed a cross-tissue and cross-phenotypic analysis of genome-wide methylomic variation in AUD using samples from 3 discovery, 4 replication, and 2 translational cohorts. We identified a differentially methylated region in the promoter of the proprotein convertase subtilisin/kexin 9 (PCSK9) gene that was associated with disease phenotypes. Biological validation showed that PCSK9 promoter methylation is conserved across tissues and positively correlated with expression. Replication in AUD datasets confirmed PCSK9 hypomethylation and a translational mouse model of AUD showed that alcohol exposure leads to PCSK9 downregulation. PCSK9 is primarily expressed in the liver and regulates low-density lipoprotein cholesterol (LDL-C). Our finding of alcohol-induced epigenetic regulation of PCSK9 represents one of the underlying mechanisms between the well-known effects of alcohol on lipid metabolism and cardiovascular risk, with light alcohol use generally being protective while chronic heavy use has detrimental health outcomes.


Subject(s)
Alcoholism/genetics , Proprotein Convertase 9/drug effects , Proprotein Convertase 9/genetics , Adult , Alcoholism/physiopathology , Animals , Cholesterol, LDL/metabolism , DNA Methylation/genetics , Epigenesis, Genetic/genetics , Epigenomics/methods , Ethanol/adverse effects , Ethanol/metabolism , Female , Gene Expression Regulation/genetics , Humans , Lipid Metabolism/genetics , Liver/metabolism , Male , Mice , Phenotype , Promoter Regions, Genetic/genetics , Proprotein Convertase 9/physiology , Rats , Rats, Wistar
3.
Article in English | MEDLINE | ID: mdl-29031396

ABSTRACT

Omega-3 long-chain polyunsaturated fatty acids (LCPUFAS) modulate immune cells in vitro and in vivo. This study investigated the effects of enriching the maternal diet with the n-6 and n-3 LCPUFAs, arachidonic (20:4n-6, 0.6%wt ARA) and docosahexaenoic acid (22:6n-3, 0.32%wt DHA), or 1:1 and 2:1 ratios (ARA: DHA) on total lipids in milk, total lipids, and immunophenotypes in plasma, lymph nodes, and spleen from isolated immune cells from 28d old pups. From day 15 of gestation to day 3 pp, Sprague-Dawley dams were fed a commercial chow. On day 3 pp litters were culled and pups (4 males and 2 females) randomly cross-fostered to dams who were randomized to one of the 5 experimental diets resulting in 20 male and 10 female pups/diet group. Dams fed ARA or ARA: DHA had 28-36% more 20:4n-6 in milk and feeding DHA or ARA: DHA doubled 22:6n-3 in milk lipids (P<0.05). Feeding 1:1 or 2:1 ARA: DHA resulted in greater pup weight at weaning (P<0.05). Compared to the control pups, ARA + DHA fed pups had a lower proportion of splenic CD45RA+ lymphocytes. In summary, postpartum supplementation with a combination of ARA + DHA, compared to ARA or DHA alone, resulted in a higher content of ARA and DHA in dam's milk and tissues and had positive effects on growth, accompanied by evidence of progression toward a mature immune phenotype, and suggests a need for ARA when DHA is supplemented in the early diet. Additional investigations are needed of ARA immunomodulation to better understand and estimate nutritional requirements for LCPUFAs during early development.


Subject(s)
Animals, Suckling/growth & development , Arachidonic Acid/administration & dosage , Dietary Supplements , Docosahexaenoic Acids/administration & dosage , Animals , Animals, Newborn/metabolism , Animals, Suckling/immunology , Body Weight/drug effects , Female , Lactation/drug effects , Rats
4.
Curr Alzheimer Res ; 7(3): 190-6, 2010 May.
Article in English | MEDLINE | ID: mdl-20088810

ABSTRACT

Memory loss is a prominent health concern, second only to heart disease for older individuals. Docosahexaenoic acid (DHA), the principle omega-3 fatty acid in brain and heart, plays an important role in neural and cardiac function. Decreases in plasma DHA are associated with cognitive decline in healthy elderly and Alzheimer's patients. Higher DHA intake and plasma levels are inversely correlated with increased relative risk of Alzheimer's disease (AD) and fatal coronary heart disease. DHA provides well known cardiovascular benefits (e.g. lower triglycerides, increased HDL cholesterol, decreased resting heart rate) in older adults. Preclinically, DHA supplementation restores brain DHA levels, enhances learning and memory tasks in aged animals, and significantly reduces beta amyloid, plaques, and tau in transgenic AD models. To date, clinical studies with DHA+EPA supplementation have shown some positive effects in mild cognitive impairment but not in AD, suggesting that early intervention may be a key factor to providing effective therapies. A recent clinical study examined individual effects of 900mg/d algal DHA as a nutritional supplement for age-related cognitive decline (ARCD). This randomized, double blind, placebo controlled study (n=485) found significantly fewer CANTAB Paired Associate Learning errors with algal DHA at six months versus placebo (diff. score -1.63+/-0.76, p=0.03). Positive effects on Verbal Recognition Memory (p<0.02) and significant decreases in resting heart rate with DHA (p<0.03) were observed, indicating improved learning and episodic memory functions and cardiovascular benefits for ARCD. Collectively, data reveal a potentially beneficial role for DHA in preventing or ameliorating cognitive decline and cardiovascular disease in the aged.


Subject(s)
Cardiovascular Diseases/drug therapy , Cognition Disorders/drug therapy , Docosahexaenoic Acids/pharmacology , Memory Disorders/drug therapy , Adult , Aged , Aging/pathology , Brain/drug effects , Brain/metabolism , Brain/physiopathology , Cardiovascular Diseases/physiopathology , Cardiovascular Diseases/prevention & control , Cognition Disorders/physiopathology , Cognition Disorders/prevention & control , Dietary Supplements , Docosahexaenoic Acids/metabolism , Docosahexaenoic Acids/therapeutic use , Female , Humans , Hypolipidemic Agents/pharmacology , Hypolipidemic Agents/therapeutic use , Male , Memory Disorders/physiopathology , Memory Disorders/prevention & control , Middle Aged , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Neuropsychological Tests , Nootropic Agents/pharmacology , Nootropic Agents/therapeutic use , Treatment Outcome
5.
Head Neck ; 30(2): 170-7, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17694555

ABSTRACT

BACKGROUND: Postoperative complications are relevant outcomes in patients with head and neck tumor who have undergone surgery. Few trials have assessed predictive factors in older patients. We assessed the predictive effect of preoperative clinical factors on postoperative complications. METHODS: We conducted a cohort study with 242 patients older than 70 years with head and neck cancer who underwent surgery. Logistic regression identified predictive factors for postoperative complications. Significant variables were used to build a predictive index. RESULTS: Comorbidities were present in 87.6% of patients, and 56.6% had some type of complication (44.6% local and 28.5% systemic). Male sex, bilateral neck dissection, presence of 2 or more comorbidities, reconstruction, and clinical stage IV were associated with postoperative complications. The predictive index showed a receiver operating characteristics curve (ROC) area of 0.69. CONCLUSION: It is possible to predict postoperative complications in older patients with head and neck tumors who underwent oncologic surgery using clinical preoperative variables.


Subject(s)
Head and Neck Neoplasms/surgery , Postoperative Complications/epidemiology , Aged , Aged, 80 and over , Comorbidity , Diabetes Mellitus/epidemiology , Female , Humans , Logistic Models , Male , Prognosis , ROC Curve , Surgical Wound Infection/epidemiology
6.
Oral Oncol ; 40(1): 71-6, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14662418

ABSTRACT

The objective of this study was to analyze the influence of changes in the treatment on the prognosis of patients treated over 44 years in a single institution. The 5-decade trends in treatment approach and 5-year survival of 3267 patients treated between 1953 and 1997 were analyzed. An increase was observed in primary surgical treatment and its association with radiotherapy. In the 1950s, 29.1% of the patients were treated by surgery, 54.5% by radiotherapy and 16.4% by combined treatment; in the 1990s, these proportions were 39.7, 9.7 and 50.6%, respectively (P<0.001). There was a significant increase in the 5-year survival rates from 28.7% for patients treated in the 1950s to 43.2% in the 1990s (P<0.001). The changes in treatment approach for oral and oropharyngeal cancer over the last 5 decades, with an increase of surgical treatment and its combination with radiotherapy significantly improved the survival rates.


Subject(s)
Oropharyngeal Neoplasms/mortality , Brazil/epidemiology , Female , Humans , Male , Middle Aged , Mortality/trends , Oropharyngeal Neoplasms/radiotherapy , Oropharyngeal Neoplasms/surgery , Prognosis , Regression Analysis , Survival Analysis , Survival Rate
7.
Monaldi Arch Chest Dis ; 58(2): 95-100, 2002 Sep.
Article in Italian | MEDLINE | ID: mdl-12418421

ABSTRACT

RATIONALE: In the management of heart failure the general practitioner (GP) plays an important role. However, international studies proved that the GP differs in the management of these patients from the cardiologist. This pilot study aims at investigating if such differences persist in the Italian community. MATERIALS AND METHODS: Seventy patients with heart failure have been enrolled prospectively by 10 GPs in the Udine district (ASL 4). All of them have been evaluated at the first and subsequent visits, both with respect to clinical and instrumental parameters, overall resource consumption and quality of life. RESULTS: We observed a high degree of heterogeneity in the follow up patterns; a low coordination between GP and cardiologists in managing patients; several co-morbidities; high social burden; a good adherence to treatment guidelines; a moderate workload, subjectively evaluated from the GP. CONCLUSIONS: This experience motivated the need of further research in the field, and, from the point of view of the daily practice, the need of integrating hospital and community management of patients with heart failure.


Subject(s)
Heart Failure/therapy , Aged , Aged, 80 and over , Chronic Disease , Female , Health Resources/statistics & numerical data , Humans , Italy , Male , Pilot Projects , Prospective Studies
10.
Am J Physiol ; 277(3): C563-71, 1999 09.
Article in English | MEDLINE | ID: mdl-10484343

ABSTRACT

We have demonstrated the expression of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, mRNA, and protein within the rat and human brains, in areas regulating sexual differentiation and function. We have found that GT1-7, a gonadotropin-releasing hormone (GnRH)-secreting hypothalamic neuronal cell line, expresses the CFTR gene, mRNA, and protein and cAMP-dependent (36)Cl efflux. A linear 7-pS Cl- conductance, which is stimulated by ATP and cAMP analogs and inhibited by glibenclamide, consistent with CFTR activity, has been identified in GT1-7 cells. Antisense oligo(dN) generated against exon 10 of the CFTR gene transcript (mRNA) inhibit GnRH secretion into media [312 +/- 73, 850 +/- 150, 963 +/- 304, and 912 +/- 74 pg GnRH/4 x 10(6) cells for antisense, sense, missense, and no oligo(dN), respectively; P < 0. 029 for antisense oligo(dN)-treated vs. normal cells]. No changes in intracellular synthesis of GnRH were noted [1,400 +/- 371 and 1,395 +/- 384 pg GnRH/4 x 10(6) cells for antisense and sense oligo(dN), respectively]. Antisense oligo(dN), but not sense or missense oligo(dN), inhibited cAMP-dependent 36Cl efflux. The expression of CFTR protein, detected by Western blotting, was also inhibited 68% by preincubation of cells with antisense oligo(dN). GT1-7 hypothalamic neurons express the CFTR gene, mRNA, and protein, which modulate neurosecretion. Abnormal neuropeptide vesicle trafficking by mutant CFTR may help to explain some of the diverse manifestations of cystic fibrosis.


Subject(s)
Cystic Fibrosis Transmembrane Conductance Regulator/physiology , Gonadotropin-Releasing Hormone/metabolism , Hypothalamus/metabolism , Neurons/metabolism , 3T3 Cells , Animals , Blotting, Western , Cell Line , Cyclic AMP/physiology , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Hypothalamus/cytology , In Situ Hybridization , Mice , Oligonucleotides, Antisense/pharmacology , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction
11.
Br J Clin Pharmacol ; 46(3): 215-9, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9764961

ABSTRACT

AIMS: The aim of this study was to investigate whether chloroquine can inhibit drug metabolism in humans, if such inhibition is general or selective for certain enzymes and evaluate the potential for and clinical significance of any drug-drug interactions when chloroquine is co-administered with other drugs. METHODS: The study was conducted in fourteen normal non-smoking healthy male volunteers using a cocktail of five drugs consisting of caffeine, mephenytoin, debrisoquine, chlorzoxazone and dapsone to assess activities of cytochromes P450 (CYP) 1A2, 2C19, 2D6, 2E1 and 3A4 respectively. Dapsone was also used to assess N-acetyltransferase activity. The activities were assessed at baseline, after one and seven daily doses (250 mg daily) of chloroquine and 7 and 14 days after stopping chloroquine dosing. RESULTS: Chloroquine caused a progressive and significant decrease in CYP2D6 activity as measured by debrisoquine metabolism from first to seventh dose and the activity returned to baseline gradually over 14 days after stopping administration. There was no effect on the metabolism of any of the other probe drugs. CONCLUSIONS: Chloroquine has been shown to be capable of inhibiting the activity of CYP2D6 in vivo in humans. This effect is selective as activities of other enzymes investigated were not affected. The effect was modest but suggests a potential for drug-drug interactions when co-administered with other drugs that are substrates for this enzyme. The clinical significance of such an interaction will depend on the therapeutic index of any drug involved.


Subject(s)
Antimalarials/pharmacology , Chloroquine/pharmacology , Cytochrome P-450 Enzyme Inhibitors , Isoenzymes/antagonists & inhibitors , Adult , Analysis of Variance , Antimalarials/administration & dosage , Caffeine/administration & dosage , Chloroquine/administration & dosage , Chlorzoxazone/administration & dosage , Cytochrome P-450 Enzyme System/metabolism , Dapsone/administration & dosage , Debrisoquin/administration & dosage , Debrisoquin/metabolism , Drug Administration Schedule , Drug Interactions , Humans , Isoenzymes/metabolism , Male , Phenotype
12.
Am J Physiol ; 275(3): C653-60, 1998 09.
Article in English | MEDLINE | ID: mdl-9730948

ABSTRACT

The cystic fibrosis transmembrane conductance regulator (CFTR) can be activated by protein kinase A (PKA)- or protein kinase C (PKC)-dependent phosphorylation. To understand how activation of both kinases affects CFTR activity, transfected NIH/3T3 cells were stimulated with forskolin (FSK), phorbol myristate acetate (PMA), or prostaglandin F2alpha (PGF). PGF stimulates inositol trisphosphate and cAMP production in NIH/3T3 cells. As measured by I- efflux, maximal CFTR activity with PGF and FSK was equivalent and fivefold greater than that with PMA. Both PGF and PMA had additive effects on FSK-dependent CFTR activity. PMA did not increase cellular cAMP, and maximal PGF-dependent CFTR activity occurred with approximately 20% of the cellular cAMP observed with FSK-dependent activation. Staurosporine, but not H-89, inhibited CFTR activation and in vivo phosphorylation at low PGF concentrations. In contrast, at high PGF concentrations, CFTR activation and in vivo phosphorylation were inhibited by H-89. As judged by protease digestion, the sites of in vivo CFTR phosphorylation with FSK and PMA differed. For PGF, the data were most consistent with in vivo CFTR phosphorylation by PKA and PKC. Our data suggest that activation of PKC can enhance PKA-dependent CFTR activation.


Subject(s)
Cyclic AMP-Dependent Protein Kinases/metabolism , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , Dinoprost/pharmacology , Protein Kinase C/metabolism , Sulfonamides , 3T3 Cells , Animals , Colforsin/pharmacology , Cystic Fibrosis Transmembrane Conductance Regulator/drug effects , Enzyme Inhibitors/pharmacology , Inositol 1,4,5-Trisphosphate/metabolism , Iodides/metabolism , Isoquinolines/pharmacology , Kinetics , Mice , Phosphopeptides/chemistry , Phosphopeptides/isolation & purification , Phosphorylation , Recombinant Proteins/metabolism , Staurosporine/pharmacology , Tetradecanoylphorbol Acetate/pharmacology , Transfection
13.
J Clin Pharmacol ; 38(1): 82-9, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9597564

ABSTRACT

Chlorzoxazone is being developed and proposed for use as a probe to measure in vivo cytochrome P4502E1 activity, but the phenotypic trait measures that are used vary. Although the doses proposed for phenotyping range from 250 mg to 750 mg, the effect of dose on chlorzoxazone hydroxylation has not previously been evaluated. The purpose of this study was to characterize the pharmacokinetics of chlorzoxazone in normal healthy volunteers (N = 6) after single randomized oral doses of 250 mg and 750 mg. An additional 10 volunteers underwent a detailed pharmacokinetic study using the 250-mg dose to further evaluate proposed phenotypic trait measures (N = 16). Timed blood and urine samples were obtained for 10 hours for chlorzoxazone and 6-hydroxychlorzoxazone determination by HPLC. Pharmacokinetic parameter estimates were estimated using noncompartmental methods. Evaluation of phenotypic trait measures show that 6-hydroxychlorzoxazone to chlorzoxazone plasma concentration ratios at 2 to 4 hours after drug administration demonstrated the highest correlations with metabolite formation clearance (r = 0.9; P < 0.001). Urine-based parameters (e.g., total recovery) were not significantly related to formation clearance (r = 0.5; P > 0.05). Dose dependency in chlorzoxazone metabolism was shown by a 30% increase (P < 0.05) in the dose-normalized area under the concentration-time curve (AUC) of chlorzoxazone and lower incremental dose-normalized urinary recovery of 6-hydroxychlorzoxazone at early timepoints after the 750-mg dose. In addition, the plasma ratio of 6-hydroxychlorzoxazone to chlorzoxazone at 4 hours was reduced by 48% in 5 of 6 subjects after the 750-mg dose (P > 0.05). These data suggest that 6-hydroxylation was saturated at the higher dose and illustrate the importance of dose selection in phenotyping. The results of this study indicate that a chlorzoxazone dose of 250 mg should be used and that a single plasma ratio obtained 2 to 4 hours after dosing is reflective of chlorzoxazone 6-hydroxylation and thus may serve as a cytochrome P4502E1 phenotypic trait measure.


Subject(s)
Chlorzoxazone/pharmacokinetics , Cytochrome P-450 CYP2E1/metabolism , Muscle Relaxants, Central/pharmacokinetics , Adolescent , Adult , Chlorzoxazone/administration & dosage , Dose-Response Relationship, Drug , Humans , Hydroxylation , Male , Phenotype
14.
Am J Physiol ; 271(2 Pt 1): C650-7, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8770006

ABSTRACT

We have previously shown [B. Illek, H. Fischer, G. F. Santos, J. H. Widdicombe, T. E. Machen, and W. W. Reenstra, Am. J. Physiol. 268 (Cell Physiol. 37): C886-C893, 1995] that genistein, a tyrosine kinase inhibitor, activates the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel in NIH/3T3 cells that have been stably transfected with an expression vector for the CFTR (NIH-CFTR cells). In this study, we present evidence suggesting that both genistein and the serine/threonine protein phosphatase (PPase) inhibitor calyculin A activate the CFTR by inhibiting PPase activity. As measured by 125I efflux, genistein and calyculin A stimulate the CFTR to approximately 50% of the maximal activity with forskolin. Neither agonist increases CFTR activity at saturating forskolin concentrations, but genistein and calyculin A have an additive effect on CFTR activity. Forskolin, but neither genistein nor calyculin A, stimulates protein kinase A(PKA) activity. The PKA inhibitor H-89 inhibits CFTR activation and in vivo phosphorylation by all three agonists. Proteolytic digestion of in vivo phosphorylated CFTR suggests that the CFTR is phosphorylated on the same sites during stimulation with genistein and forskolin but on different sites stimulation with calyculin A. The data suggest that genistein and calyculin A inhibit different PPase activities, allowing CFTR phosphorylation and partial stimulation, by a basal PKA activity.


Subject(s)
Cystic Fibrosis Transmembrane Conductance Regulator/drug effects , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , Isoflavones/pharmacology , Phosphoprotein Phosphatases/physiology , Sulfonamides , 3T3 Cells , Animals , Colforsin/pharmacology , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Drug Synergism , Genistein , Isoquinolines/pharmacology , Marine Toxins , Mice , Oxazoles/pharmacology , Phosphoprotein Phosphatases/antagonists & inhibitors , Protein Kinase Inhibitors , Transfection
15.
J Neurosci Res ; 43(4): 476-81, 1996 Feb 15.
Article in English | MEDLINE | ID: mdl-8699533

ABSTRACT

Activated calpain I immunoreactivity (76 kDa band) was detected in membranes prepared from rat brain hippocampal slices using a polyclonal antiserum raised against an N-terminus peptide of the cleaved subunit of calpain I. While basal levels of activated calpain I were stable over incubation times, 1 nM dopamine (DA) produced an initial 32% increase (5 min) in the 76 kDa protein followed by a 53% decrease in this band at 20 min of incubation. The DA-induced changes in activated calpain I immunoreactivity were blocked by the calpain inhibitor peptide, N-acetyl-Leu-Leu-norleucinal(100 microM) or by EGTA. Basal levels of the 76 kDa band were not affected by the calpain inhibitor. These changes in activated calpain I, elicited by DA, are in accord with the DA-induced decreases in the levels of the calpain substrate, gamma PKC (Yurko-Mauro and Friedman; J Cell Biochem [Abstr] 180:80, 1994; J Neurochem 65: 1622-1630, 1995) and suggest that DA activates this Ca(++)-dependent protease in its regulation of neuronal signal transduction.


Subject(s)
Calpain/metabolism , Dopamine/pharmacology , Hippocampus/drug effects , Animals , Calpain/antagonists & inhibitors , Enzyme Activation , Hippocampus/enzymology , Immunohistochemistry , In Vitro Techniques , Male , Rats , Rats, Sprague-Dawley , Stimulation, Chemical
16.
In. Fundaçäo Antonio Prudente. Hospital A. C. Camargo. Manual de condutas diagnósticas e terapêuticas em oncologia. Säo Paulo, Ambito Editores, 1996. p.256-261.
Monography in Portuguese | LILACS | ID: lil-180283
17.
J Neurochem ; 65(4): 1622-30, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7561857

ABSTRACT

The effect of dopamine (DA) receptor stimulation on the distribution of gamma protein kinase C (gamma PKC) in hippocampal slices was assessed. Nanomolar concentrations of DA decreased cytosolic gamma PKC (56%) without altering membrane gamma PKC levels, resulting in decreased total gamma PKC immunoreactivity. The maximal decrease in cytosolic gamma PKC occurred at 20 min of incubation and was significantly blocked by the D1 DA antagonist SCH 23390 (10(-6) M) but not by the D2 antagonist sulpiride (10(-5) M). The D1 agonists SKF 38393 and A 77636 mimicked the effect of DA with similar responses produced at 10 microM and 1 nM, respectively. The D2 agonist quinpirole had no effect on gamma PKC immunoreactivity, thus indicating that this dopaminergic response is mediated through a D1-like receptor. DA had no effect on alpha, delta, or zeta PKC isozyme immunoreactivity in the same hippocampal preparations. The DA-induced decrease in cytosolic gamma PKC immunoreactivity was blocked by the Ca(2+)-dependent protease inhibitor N-acetyl-Leu-Leu-norleucinal (100 microM) and by the inorganic Ca2+ channel blocker Co2+. The data suggest that DA stimulates a D1-like DA receptor, which increases the influx of Ca2+ and activates the Ca(2+)-dependent proteolysis of gamma PKC.


Subject(s)
Calcium/physiology , Cytosol/enzymology , Hippocampus/enzymology , Peptide Hydrolases/metabolism , Protein Kinase C/metabolism , Receptors, Dopamine/physiology , Animals , Calpain/antagonists & inhibitors , Dopamine/pharmacology , Dopamine Agonists/pharmacology , Dopamine Antagonists/pharmacology , Extracellular Space/metabolism , In Vitro Techniques , Isoenzymes/metabolism , Male , Rats , Rats, Sprague-Dawley
18.
N Engl J Med ; 327(7): 501, 1992 Aug 13.
Article in English | MEDLINE | ID: mdl-1625749
19.
Am J Hypertens ; 3(1): 48-51, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2405883

ABSTRACT

Left ventricular diastolic filling was investigated in 12 black and 15 white subjects before and after double-blinded randomized treatment of mild to moderate hypertension with combined alpha- and beta-adrenergic receptor blockade (labetalol) and beta-blockade alone (atenolol). At baseline (off medication), both groups were similar for age (46 +/- 8 years v 48 +/- 12 years), mean blood pressure (121 +/- 8 mm Hg v 115 +/- 8 mm Hg), left ventricular dimensions, left ventricular mass index (118 +/- 24 g/m2 v 113 +/- 13 g/m2), and left ventricular filling as reflected by transmitral flow velocity ratio A/E (0.97 +/- 0.33 v 0.92 +/- 0.19, normal age-matched control A/E ratio is 0.64 +/- 14). There were 6 blacks and 6 whites in the labetalol group; 6 blacks and 9 whites in the atenolol group. At six weeks of treatment, whites in the labetalol group showed a significantly greater drop in mean blood pressure (114 +/- 7/102 +/- 11, P less than .007 v 123 +/- 9/114 +/- 11, P = NS) and correspondingly greater improvement in A/E ratio (1.04 +/- 0.14/0.74 +/- 0.23, P less than .024 v 1.02 +/- 0.23/0.89 +/- 0.16, P = NS). However, this difference was no longer significant when controlling for age and blood pressure level. In the atenolol group, whites showed a significant increase in the rapid filling phase velocity E, while late filling phase velocity A significantly dropped only in blacks, without significant improvement in A/E ratio in either subgroup. In conclusion, greater improvement in left ventricular filling is seen with combined alpha-beta-blockade than beta-blockade alone.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Atenolol/pharmacology , Cardiac Volume/drug effects , Heart Ventricles/physiopathology , Hypertension/physiopathology , Labetalol/pharmacology , Adult , Analysis of Variance , Black People , Diastole , Double-Blind Method , Echocardiography, Doppler , Female , Heart Ventricles/drug effects , Humans , Hypertension/drug therapy , Male , Middle Aged , Randomized Controlled Trials as Topic , United States , White People
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