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2.
Br J Cancer ; 107(3): 482-90, 2012 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-22735904

RESUMO

BACKGROUND: Recently, the management of head and neck squamous cell carcinoma (HNSCC) has focused considerable attention on biomarkers, which may influence outcomes. Tests for human papilloma infection, including direct assessment of the virus as well as an associated tumour suppressor gene p16, are considered reproducible. Tumours from familial melanoma syndromes have suggested that nuclear localisation of p16 might have a further role in risk stratification. We hypothesised p16 staining that considered nuclear localisation might be informative for predicting outcomes in a broader set of HNSCC tumours not limited to the oropharynx, human papilloma virus (HPV) status or by smoking status. METHODS: Patients treated for HNSCC from 2002 to 2006 at UNC (University of North Carolina at Chapel Hill) hospitals that had banked tissue available were eligible for this study. Tissue microarrays (TMA) were generated in triplicate. Immunohistochemical (IHC) staining for p16 was performed and scored separately for nuclear and cytoplasmic staining. Human papilloma virus staining was also carried out using monoclonal antibody E6H4. p16 expression, HPV status and other clinical features were correlated with progression-free (PFS) and overall survival (OS). RESULTS: A total of 135 patients had sufficient sample for this analysis. Median age at diagnosis was 57 years (range 20-82), with 68.9% males, 8.9% never smokers and 32.6% never drinkers. Three-year OS rate and PFS rate was 63.0% and 54.1%, respectively. Based on the p16 staining score, patients were divided into three groups: high nuclear, high cytoplasmic staining group (HN), low nuclear, low cytoplasmic staining group (LS) and high cytoplasmic, low nuclear staining group (HC). The HN and the LS groups had significantly better OS than the HC group with hazard ratios of 0.10 and 0.37, respectively, after controlling for other factors, including HPV status. These two groups also had significantly better PFS than the HC staining group. This finding was consistent for sites outside the oropharynx and did not require adjustment for smoking status. CONCLUSION: Different p16 protein localisation suggested different survival outcomes in a manner that does not require limiting the biomarker to the oropharynx and does not require assessment of smoking status.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/genética , Estudos de Casos e Controles , Núcleo Celular/genética , Núcleo Celular/metabolismo , Estudos de Coortes , Inibidor p16 de Quinase Dependente de Ciclina/genética , Intervalo Livre de Doença , Feminino , Genes Supressores de Tumor , Neoplasias de Cabeça e Pescoço/genética , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae/genética , Papillomaviridae/metabolismo , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço , Taxa de Sobrevida , Adulto Jovem
3.
Aliment Pharmacol Ther ; 33(2): 225-34, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21083673

RESUMO

BACKGROUND: Cough may be a manifestation of gastro-oesophageal reflux disease (GERD). The utility of acid suppression in GERD-related cough is uncertain. AIM: To assess the impact of high-dose acid suppression with proton pump inhibitors (PPI) on chronic cough in subjects with rare or no heartburn. METHODS: Subjects were nonsmokers without history of asthma, with chronic cough for >8 weeks. All subjects underwent a baseline 24-h pH/impedance study, methacholine challenge test and laryngoscopy. Subjects were randomised to either 40 mg of esomeprazole twice daily or placebo for 12 weeks. The primary outcome measure was the Cough-Specific Quality of Life Questionnaire (CQLQ). Secondary outcomes were response on Fisman Cough Severity/Frequency scores and change in laryngeal findings. RESULTS: Forty subjects were randomised (22 PPI, 18 placebo) and completed the study. There was no difference between PPI and placebo in CQLQ (mean improvement 9.8 vs. 5.9 respectively, P = 0.3), or Fisman Cough Severity/Frequency scores. Proportion of patients who improved by >1 s.d. on the CQLQ was 27.8% (five of 18) and 31.8% (seven of 22) in the placebo and PPI groups respectively. CONCLUSION: In subjects with chronic cough and rare or no heartburn, high-dose proton pump inhibitor does not improve cough-related quality of life or symptoms.


Assuntos
Tosse/tratamento farmacológico , Esomeprazol/uso terapêutico , Refluxo Gastroesofágico/complicações , Inibidores da Bomba de Prótons/uso terapêutico , Adolescente , Adulto , Idoso , Doença Crônica , Tosse/complicações , Método Duplo-Cego , Feminino , Refluxo Gastroesofágico/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Estatística como Assunto , Resultado do Tratamento , Adulto Jovem
4.
Bone Marrow Transplant ; 29(3): 257-61, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11859399

RESUMO

An understanding of the factors that place the post-transplant patient at increased risk for sinusitis would help identify patients likely to develop disease and possibly allow for interventions that would decrease the incidence or severity of sinus disease. This retrospective study investigates the ability of screening paranasal sinus computed tomographic scans (CTs), clinical history, and potential risk factors for sinusitis, including history of tobacco use, history of allergies or asthma, IgG level, history of sinusitis, remission status and acute graft-versus-host disease (GVHD) to predict post-transplant sinusitis. Medical records and sinus CTs of 100 allogeneic bone marrow recipients were reviewed. There was no increased risk of developing sinusitis post SCT for patients with significant disease on screening CT, symptoms at time of transplant, a history of tobacco use, asthma or allergies, low IgG level, history of sinusitis or for patients at high risk of relapse. Patients with GVHD were 4.3 times more likely than patients without GVHD to develop sinusitis post transplant (95% CI: 1.7-11.0, P = 0.002). Acute GVHD places patients at greater risk of developing sinus infections.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Sinusite/etiologia , Adulto , Idoso , Doença Enxerto-Hospedeiro/complicações , Humanos , Pessoa de Meia-Idade , Doenças dos Seios Paranasais/diagnóstico , Doenças dos Seios Paranasais/diagnóstico por imagem , Seios Paranasais/diagnóstico por imagem , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Sinusite/prevenção & controle , Tomografia Computadorizada por Raios X
5.
Adv Otorhinolaryngol ; 56: 279-88, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10868246

RESUMO

The ongoing preclinical and now human clinical investigation of gene therapy in head and neck cancer and cancer and cancer overall have provided a few foundation points of information. The first point is that viral and nonviral gene therapy has demonstrated efficacy in a variety of animal models and these successes support consideration and evaluation of gene therapy in human clinical trials. Regarding the retrovirus as a vehicle for gene transfer in humans, it appears to be a safe vehicle. There has been no significant short- or long-term toxicity associated with a wide application of retroviral gene therapy in human patients [12]. Regarding adenovirus as a vehicle, there are less numbers and less advanced trials, but the associated toxicities reported thus far have been both transient and relatively minor. Nonviral cationic lipid-mediated gene transfer also appears safe in human patients. These points are significant because they establish the safety foundation for delivering potentially therapeutic genes to humans. Without this safety data, gene therapy would not have a future in the treatment of cancer. At the present Phase I stage of human clinical trial investigation for head and neck cancer, the focus remains on patients with advanced or recurrent incurable cancer. Although this patient population is a standard choice for establishing the safety of novel therapies, the greatest chance of eventual success with currently available gene transfer vehicles and gene therapy strategies will most likely be in those patients with less advanced stages of disease. Another future potential for gene therapy in head and neck cancer may be in combination with surgery or radiation or chemotherapy. At some acceptable ratio of efficacy to toxicity, gene therapy may also prove effective against earlier stage cancer either as a primary or adjuvant therapy. In conjunction with the evolution of molecular diagnostics, gene therapy strategies may provide the means for preventing the malignant progression of premalignant head and neck lesions upon early diagnosis.


Assuntos
Citocinas/genética , Genes Supressores de Tumor , Terapia Genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/terapia , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos
6.
AIHAJ ; 61(2): 214-22, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10782193

RESUMO

The components of carbonless copy paper (CCP) and the chemistry involved in its manufacture are reviewed. Claims that the routine use of CCP can cause health problems ranging from skin, eye, and lung irritation to severe headaches and neurological damage are described; yet no definitive studies have been conducted that show correlation between CCP use and these symptoms. The toxicological properties of CCP components, many of them precursors to the dye-containing microcapsules or dye solvents that may be causing these problems, are discussed. Recommendations for the minimization of possible physiological reactions to CCP include reduction of usage time; use of the CCP in a well-ventilated area; storing large quantities of CCP, both new or archived, away from work area; and the practice good hand hygiene.


Assuntos
Processos de Cópia , Irritantes , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Papel , Humanos , Hidrocarbonetos/efeitos adversos , Irritantes/efeitos adversos , Estatística como Assunto
7.
Arch Otolaryngol Head Neck Surg ; 125(12): 1371-4, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10604417

RESUMO

OBJECTIVE: To quantitate the functional morbidity to the hand and wrist following harvest of a radial forearm fasciocutaneous free flap. DESIGN: Prospective case-control study, with each patient providing his or her internal control, comparing preoperative and postoperative operated to nonoperated forearms. SETTING: Tertiary care hospital in large metropolitan area. PATIENTS: A consecutive sample of 11 patients who underwent a radial forearm free flap reconstruction of the head and neck from April 1997 to May 1998. MAIN OUTCOME MEASURES: Range of motion of the wrist (flexion and extension, ulnar and radial deviation), grip and pinch strength, and sharp and dull sensation in the distribution of the radial, ulnar, and median nerves. RESULTS: Statistically significant differences (P<.05) were measured in wrist flexion, pinch strength, and sharp sensation in the anatomical snuffbox of the operated forearm. No subjective complaints of loss of function were reported by any patient. CONCLUSIONS: Donor-site functional morbidity associated with harvest of the radial forearm fasciocutaneous free flap is measurable. The statistical differences found do not translate into subjective patient complaints of everyday functional morbidity.


Assuntos
Antebraço/cirurgia , Transplante de Pele/efeitos adversos , Retalhos Cirúrgicos/efeitos adversos , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Sobrevivência de Enxerto , Força da Mão , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Prospectivos , Nervo Radial/fisiopatologia , Nervo Ulnar/fisiopatologia , Punho/fisiopatologia
9.
Arch Otolaryngol Head Neck Surg ; 124(9): 1003-7, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9738810

RESUMO

BACKGROUND: A significant proportion of burn patients with inhalation injuries incur difficulties with airway protection, dysphagia, and aspiration. In assessing the need for intubation in burn patients, the efficacy of fiberoptic laryngoscopy was compared with clinical findings and the findings of diagnostic tests, such as arterial blood gas analysis, measurement of carboxyhemoglobin levels, pulmonary function tests, and radiography of the lateral aspect of the neck. OBJECTIVE: To determine if these patients were at risk for aspiration or dysphagia, barium-enhanced fluoroscopic swallowing studies were performed. DESIGN: Prospective study. SETTINGS: Burn intensive care unit in an academic tertiary referral center. MAIN OUTCOME MEASURES: Need for endotracheal intubation and potential for aspiration. RESULTS: Six (55%) of 11 patients had clinical findings and symptoms that indicated, under traditional criteria, endotracheal intubation for airway protection. Visualization of the upper airway with fiberoptic laryngoscopy obviated the need for endotracheal intubation in all 11 patients. These patients also failed to evidence an increased risk of aspiration or other swallowing dysfunction. CONCLUSIONS: In comparison with other diagnostic criteria, fiberoptic laryngoscopy allows differentiation of those patients with inhalation injuries who, while at risk for upper airway obstruction, do not require intubation. These patients may be safely observed in a monitored setting with serial fiberoptic examinations, thus avoiding the possible complications associated with intubation of an airway with a compromised mucosalized surface. In these patients, swallowing abnormalities do not manifest.


Assuntos
Queimaduras por Inalação/diagnóstico , Laringoscopia , Adulto , Algoritmos , Sulfato de Bário , Queimaduras por Inalação/terapia , Meios de Contraste , Transtornos de Deglutição/epidemiologia , Feminino , Tecnologia de Fibra Óptica , Fluoroscopia , Humanos , Intubação Intratraqueal , Laringoscópios , Laringoscopia/estatística & dados numéricos , Masculino , Pneumonia Aspirativa/epidemiologia , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco
10.
Nitric Oxide ; 1(6): 469-75, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9466952

RESUMO

The effects of arginine on nitric oxide synthase (NOS) activity and NO production were studied in pulmonary artery endothelial cells (PAEC). Incubation of PAEC with 0-100 microM arginine increased NO production, detected as nitrite in the culture medium, in a dose-dependent manner. In contrast, incubation with concentrations of arginine in excess of 100 microM resulted in a reversible dose-dependent inhibition of NO production, even though intracellular arginine content increased in these cells. The NOS enzyme kinetics were studied in a total membrane preparation and in purified NOS protein and revealed that the Km of arginine as a substrate for NOS is 3-5 microM, the Vmax occurred at 100 microM arginine, and substrate inhibition occurred at >100 microM arginine. Oxyhemoglobin, carboxy-PTIO, catalase, SOD, citrulline, hydroxyarginine, and D-arginine did not change NOS kinetics. These results indicate that substrate inhibition of eNOS exists in porcine PAEC in vitro.


Assuntos
Endotélio Vascular/enzimologia , Óxido Nítrico Sintase/antagonistas & inibidores , Artéria Pulmonar/efeitos dos fármacos , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Benzoatos/farmacologia , Membrana Celular/enzimologia , Células Cultivadas , Citrulina/metabolismo , Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos , Sequestradores de Radicais Livres/farmacologia , Imidazóis/farmacologia , Cinética , Óxido Nítrico/metabolismo , Oxiemoglobinas/farmacologia , Superóxido Dismutase/farmacologia , Suínos
11.
J Perianesth Nurs ; 12(6): 413-21, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9464030

RESUMO

Discharge criteria used in the outpatient setting of a 500-bed academic medical center were evaluated by nursing staff in two ambulatory units to determine validity in identifying patient readiness for discharge. Criteria categories include temperature, circulation, activity and mental status, pain, bleeding, voiding, and oral intake. The hospital course and post-discharge course of a convenience sample of 248 ambulatory subjects was drawn from consecutive patients. Post-discharge recovery outcomes identified by the telephone assessment included recovery, complications, necessity of further medical treatment, and the need to return to a medical facility. The descriptive results showed the safety of the seven discharge criteria. Voiding and oral intake were related to prolonged stays in the ambulatory units. Approval was granted by the Hospital Policy Board to relax discharge criteria, and make voiding and oral intake optional for patients. A stage II follow-up study of 1,582 patient subjects was conducted using the new criteria of voluntary voiding and oral intake. The average ambulatory stay was reduced 50 minutes after voiding and oral intake were made optional.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Ingestão de Líquidos , Alta do Paciente , Seleção de Pacientes , Micção , Seguimentos , Humanos , Avaliação em Enfermagem , Cuidados Pós-Operatórios
12.
Am J Physiol ; 269(5 Pt 1): L574-80, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7491975

RESUMO

Under physiological conditions, L-arginine transport by porcine pulmonary artery endothelial cells (PAEC) is mediated by system y+, a sodium-independent transport system that accounts for 60 +/- 5% of L-arginine transport, and system Bo,+, a sodium-dependent system that accounts for 40 +/- 5% of transport. Because NO production is dependent on intracellular L-arginine content and intracellular L-arginine content depends on transport of extracellular L-arginine, we examined the effect of hypoxia on L-arginine transport and intracellular L-arginine content in PAEC. Exposure of passage 3-7 PAEC in monolayer culture to 0% O2 for 4 h decreased L-arginine transport via system y+ from 120 +/- 10 to 81 +/- 23 (in pmol.mg protein-1.30 s-1) (P < 0.001), whereas 20-h exposures decreased transport from 122 +/- 17 to 84 +/- 18 (P < 0.001) in system y+ and from 104 +/- 19 to 90 +/- 26 (P < 0.05) in system Bo,+. Exposure to 5% O2 for 3-5 wk decreased L-arginine transport via system y+ from 128 +/- 15 to 73 +/- 13 (P < 0.001) and via system Bo,+, from 105 +/- 25 to 65 +/- 13 (P < 0.001). Kinetic studies revealed that hypoxia decreased the maximal transport velocity but not the apparent Michaelis constant for both system y+ and system Bo,+, and the decreases in transport were not reversible after return to normoxia for up to 24 h. Long-term exposure, i.e., 3-5 wk, to 5% O2 also resulted in decreases in intracellular L-arginine content (0.75 +/- 0.10 vs. 0.49 +/- 0.09 nmol/10(6) cells, P < 0.05) which did not reverse after return to normoxia for 24 h.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arginina/farmacocinética , Endotélio Vascular/metabolismo , Hipóxia/metabolismo , Artéria Pulmonar/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Endotélio Vascular/citologia , Membranas Intracelulares/metabolismo , Artéria Pulmonar/citologia , Suínos
13.
J Nucl Med ; 36(3): 384-93, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7884499

RESUMO

UNLABELLED: The goal of this study was to examine the relationship between D2 dopamine receptor density and levodopa dosage, disease duration and dyskinesia in Parkinson's disease (PD). METHODS: Iodine-123-iodobenzamide SPECT scans were obtained from 14 PD patients and 12 age-matched controls using a three-headed camera in conjunction with MRI and a fiducial-based image registration system to define regions of interest. Basal ganglia/cerebellum counts/voxel ratios in dorsal and ventral head of caudate and anterior and posterior putamen were measured at 30, 60, 120 and 180 min postinjection. As in 11C-raclopride studies, ratios obtained at that time when they asymptomatically approach a maximum value (180 min) were accepted as the best measure of receptor density. RESULTS: Among PD patients, a trend towards an inverse correlation between regional basal ganglia/cerebellum ratios and levodopa dosage achieved significance in ventral caudate (F = 6.244, p = 0.037); similarly, an inverse correlation between these ratios and disease duration achieved significance in anterior putamen (F = 13.144, p = 0.007). Ratios were significantly lower in anterior putamen in patients with dyskinesia (t = 3.068, p = 0.042). CONCLUSION: In PD, the previously observed inverse correlation between levodopa dosage and D2-receptor density appears to be most prominent in the least dopamine-depleted region, ventral caudate. There may be a genuine effect of disease duration on receptor density in putamen and reduced receptor density in anterior putamen may be associated with dyskinesia.


Assuntos
Benzamidas , Radioisótopos do Iodo , Doença de Parkinson/metabolismo , Pirrolidinas , Receptores de Dopamina D2/análise , Idoso , Idoso de 80 Anos ou mais , Benzamidas/farmacocinética , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Pirrolidinas/farmacocinética , Análise de Regressão , Tomografia Computadorizada de Emissão de Fóton Único
14.
N Engl J Med ; 332(11): 712-7, 1995 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-7854378

RESUMO

BACKGROUND: Although epidemiologic studies have long associated tobacco and alcohol use with the development of squamous-cell carcinoma of the head and neck, the molecular targets of these carcinogens have yet to be identified. We performed a molecular analysis to determine the pattern of mutations in the p53 gene in neoplasms from patients with squamous-cell carcinoma of the head and neck and a history of tobacco or alcohol use. METHODS: Sequence analysis of the conserved regions of the p53 gene was performed in tumor samples from 129 patients with primary squamous-cell carcinoma of the head and neck. We then used statistical analysis to identify any patient characteristics associated with mutation of the p53 gene. RESULTS: We found p53 mutations in 42 percent of the patients (54 of 129). Fifty-eight percent of the patients who smoked cigarettes and used alcohol (37 of 64; 95 percent confidence interval, 45 to 70 percent), 33 percent of the patients who smoked but abstained from alcohol (13 of 39; 95 percent confidence interval, 19 to 50 percent), and 17 percent of the patients who neither smoked nor drank alcohol (4 of 24, 95 percent confidence interval, 5 to 37 percent) had p53 mutations (P = 0.001). (Two patients used alcohol but did not smoke, and neither had a p53 mutation.) Furthermore, 100 percent of the mutations in the patients who neither drank nor smoked occurred at sites containing cytidine phosphate guanosine dinucleotides (potentially representing endogenous mutations) within the p53 gene (5 of 5 mutations; 95 percent confidence interval, 48 to 100 percent), whereas only 23 percent of those in cigarette smokers consisted of such changes (12 of 53 mutations; 95 percent confidence interval, 12 to 36 percent; P = 0.001). CONCLUSIONS: In our study, a history of tobacco and alcohol use was associated with a high frequency of p53 mutations in patients with squamous-cell carcinoma of the head and neck. Preliminary evidence linked cigarette smoking to p53 mutations at nonendogenous mutation sites. Our findings suggest a role for tobacco in the molecular progression of squamous-cell carcinoma of the head and neck and support the epidemiologic evidence that abstinence from smoking is important to prevent head and neck cancer.


Assuntos
Carcinoma de Células Escamosas/genética , Genes p53 , Neoplasias de Cabeça e Pescoço/genética , Mutação , Fumar/efeitos adversos , Composição de Bases , Carcinoma de Células Escamosas/etiologia , Intervalos de Confiança , Sequência Conservada , Análise Mutacional de DNA , Feminino , Mutação da Fase de Leitura , Neoplasias de Cabeça e Pescoço/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência
15.
Exp Physiol ; 75(4): 515-27, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2171583

RESUMO

An assay for plasma osteocalcin (BGP) in ruminants is described. Satisfactory cross-reaction was obtained for bovine BGP in several species, namely ovine, cervine, caprine and human. Sample stability at room temperature, after freezing and thawing and after lyophilization and reconstitution is described. Sheep of both sexes have been used throughout and no significant sex effect has been noted. A series of experiments showed a lack of circadian rhythm of plasma BGP concentration in sheep. Plasma BGP values from sheep ranging in age from 0.25 to 7 years fell exponentially from 300 ng/ml at 0.25 years to approximately 50 ng/ml at 1.25 years of age where it remained until the end of the study at 7 years. Long-term administration of adrenocorticotrophic hormone (ACTH) depressed plasma BGP concentrations, although plasma BGP levels were not affected sufficiently by short-term administration of ACTH to increase plasma cortisol concentrations 10-fold during a period of 4 h. It was confirmed that dietary phosphate deficiency depressed plasma BPG concentrations. It is concluded that neither circadian variation nor the short-term stress of handling and bleeding untrained animals need be considered in sampling sheep for measurement of plasma BGP concentration and that the change with age reflected the pattern of development of skeletal maturity in sheep. Values in both growing and mature sheep were at least 6 times higher than in human subjects, which may reflect the 10-fold higher skeletal growth rate in sheep than in humans. This high skeletal activity in sheep may have been selected for in the development of highly productive breeds.


Assuntos
Envelhecimento/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Ritmo Circadiano/fisiologia , Osteocalcina/sangue , Sistema Hipófise-Suprarrenal/fisiologia , Hormônio Adrenocorticotrópico , Animais , Preservação de Sangue , Reações Cruzadas , Feminino , Hidrocortisona/sangue , Masculino , Coelhos , Radioimunoensaio , Ovinos
17.
J Nucl Med ; 29(10): 1668-74, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3262726

RESUMO

Radioiodinated-SCH 23982 is a potential agent for the imaging of dopamine D-1 receptors in the human brain. In vivo binding of [125I]SCH 23982 to D-1 receptors in rat brain was determined over 4 hr. The ratio of activity in striatum and frontal cortex to that in cerebellum increased over the first 2 hr to maximum values of 4.4:1 and 2.1:1, respectively. The percent injected dose in whole brain at 0.5 and 2 hr were 0.62 and 0.15, respectively. Administration of the antagonists propranolol (beta-1), prazosin (alpha-1), haloperidol (D-2) and ketanserin (5HT-2) did not significantly alter the striatum/cerebellum ratio; however, SCH 23390, a D-1 antagonist, totally blocked ligand uptake by striatum and frontal cortex. Biologic distribution data in the rat were determined after injection of 3 microCi of [125I]SCH 23982. 76% of the injected dose was excreted in 48 hr via the liver and kidneys. Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads and red bone marrow were calculated for humans using the physical decay data for 123I. The critical organ was found to be the lower large intestine which received 1.1 rad/mCi of the administered dose. The total-body dose was 63 mrad/mCi. The data indicate that [123I]SCH 23982 should be a suitable agent for imaging the D-1 dopamine receptor in the human brain by single photon emission computed tomography.


Assuntos
Benzazepinas/análogos & derivados , Encéfalo/diagnóstico por imagem , Antagonistas de Dopamina , Radioisótopos do Iodo , Tomografia Computadorizada de Emissão , Animais , Masculino , Doses de Radiação , Ratos , Ratos Endogâmicos , Receptores Dopaminérgicos/análise , Distribuição Tecidual
18.
Arthritis Rheum ; 31(9): 1142-7, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3048274

RESUMO

We found that serum bone gamma-carboxyglutamic acid-containing protein (BGP) (osteocalcin) had lower sensitivity and specificity for measurement of disease activity in Paget's disease of bone than other biochemical measures of disease activity. The administration of diphosphonates induced suppression of urinary hydroxyproline excretion and a subsequent decrease in alkaline phosphatase values, but no consistent change in BGP values. Serum BGP measurements have limited value as a screening test for Paget's disease or for monitoring treatment of the disorder.


Assuntos
Proteínas de Ligação ao Cálcio/sangue , Difosfonatos/uso terapêutico , Osteíte Deformante/sangue , Fosfatase Alcalina/sangue , Feminino , Humanos , Hidroxiprolina/urina , Masculino , Osteíte Deformante/tratamento farmacológico , Osteíte Deformante/fisiopatologia , Osteocalcina , Valores de Referência , Sensibilidade e Especificidade , Índice de Gravidade de Doença
19.
J Cell Biochem ; 37(2): 213-23, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3165096

RESUMO

Murine squamous carcinoma cells (KLN205) grown in a medium supplemented with the retinoid, 13-cis retinoic acid (RA), had dose-dependent, selective increases in the expression of certain lectin receptors, which correlated with a dramatic decrease in the ability to form pulmonary colonies (P = .0003) (Couch MJ, Pauli BU, Weinstein RS, Coon JS: JNCI, 78:971-977, 1987). These findings suggest a possible relationship between the RA-induced glycoconjugate alterations and the decreased experimental metastatic behavior. We further define the mechanism of RA's action. The finding that RA treatment (5 X 10(-6) M, 5 X 10(-7) M) did not perturb the cell cycle of KLN205 cells provides further proof that the decreased metastatic behavior is not attributable to any inhibition in the rate of growth or to alterations in the cell cycle. Furthermore, since stable subpopulations with variable lectin binding could not be detected, the mechanism of RA's action does not appear to be due to selection of variant tumor-cell subpopulations. Finally, in a series of experiments designed to determine the reversibility of the RA treatment, the RA-induced decrease in metastatic behavior reverted back to a more metastatic state in the same time frame (3 days) as the reversion of the RA-induced changes in cell-surface glycoconjugate expression. This reversion provides further evidence for a close relationship between the RA-induced modulation of tumor cell-surface glycoconjugate expression and the decreased metastatic behavior; it suggests that transient, reversible modulation of the tumor cell surface may play a role in determining metastatic behavior.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Glicoconjugados/metabolismo , Neoplasias Pulmonares/patologia , Tretinoína/farmacologia , Animais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Ciclo Celular/efeitos dos fármacos , Citometria de Fluxo , Isotretinoína , Lectinas/metabolismo , Masculino , Camundongos , Metástase Neoplásica , Receptores Mitogênicos/metabolismo , Células Tumorais Cultivadas
20.
J Nucl Med ; 29(3): 356-62, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2894417

RESUMO

In vivo binding of [125I]-2-[beta-(3-iodo-4-hydroxyphenyl)ethylaminomethyl tetralone) ([125I]HEAT) to alpha-1 adrenoceptors in the rat brain was determined over 4 hr. Uptake in the thalamus and frontal cortex was approximately 0.1% injected dose per gram tissue. Thalamus/cerebellum ratios of 10:1 and frontal cortex/cerebellum ratios of 5:1 were found at 4 hr. Pretreatment with prazosin, an alpha-1 antagonist, completely inhibited the accumulation of [125I]HEAT in thalamus and frontal cortex; yet uptake of radioactivity was not significantly affected by antagonists and agonists for other receptors classes (propranolol, beta-1; apomorphine, D-1; spiperone, D-2). Binding of [125I]HEAT is saturable. At 4 hr, [125I]HEAT or [123I]HEAT was shown to be the only radioactive material in rat thalamus and frontal cortex. Iodine-123 HEAT and [125I]HEAT were synthesized as radiopharmaceuticals within 3 hr in 99% radiochemical purity.


Assuntos
Encéfalo/metabolismo , Radioisótopos do Iodo , Fenetilaminas/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Tetralonas , Antagonistas Adrenérgicos alfa/metabolismo , Animais , Marcação por Isótopo/métodos , Masculino , Ratos
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