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1.
Transl Psychiatry ; 7(10): e1249, 2017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29064472

RESUMO

Eye movement deviations, particularly deficits of initial sensorimotor processing and sustained pursuit maintenance, and antisaccade inhibition errors, are established intermediate phenotypes for psychotic disorders. We here studied eye movement measures of 849 participants from the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) study (schizophrenia N=230, schizoaffective disorder N=155, psychotic bipolar disorder N=206 and healthy controls N=258) as quantitative phenotypes in relation to genetic data, while controlling for genetically derived ancestry measures, age and sex. A mixed-modeling genome-wide association studies approach was used including ~4.4 million genotypes (PsychChip and 1000 Genomes imputation). Across participants, sensorimotor processing at pursuit initiation was significantly associated with a single nucleotide polymorphism in IPO8 (12p11.21, P=8 × 10-11), whereas suggestive associations with sustained pursuit maintenance were identified with SNPs in SH3GL2 (9p22.2, P=3 × 10-8). In participants of predominantly African ancestry, sensorimotor processing was also significantly associated with SNPs in PCDH12 (5q31.3, P=1.6 × 10-10), and suggestive associations were observed with NRSN1 (6p22.3, P=5.4 × 10-8) and LMO7 (13q22.2, P=7.3x10-8), whereas antisaccade error rate was significantly associated with a non-coding region at chromosome 7 (P=6.5 × 10-9). Exploratory pathway analyses revealed associations with nervous system development and function for 40 top genes with sensorimotor processing and pursuit maintenance (P=4.9 × 10-2-9.8 × 10-4). Our findings suggest novel patterns of genetic variation relevant for brain systems subserving eye movement control known to be impaired in psychotic disorders. They include genes involved in nuclear trafficking and gene silencing (IPO8), fast axonal guidance and synaptic specificity (PCDH12), transduction of nerve signals (NRSN1), retinal degeneration (LMO7), synaptic glutamate release (SH3GL2), and broader nervous system development and function.


Assuntos
Transtornos Psicóticos/genética , Transtornos Psicóticos/fisiopatologia , Acompanhamento Ocular Uniforme , Movimentos Sacádicos , Adulto , Transtorno Bipolar/complicações , Transtorno Bipolar/genética , Transtorno Bipolar/fisiopatologia , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único , Transtornos Psicóticos/complicações , Esquizofrenia/complicações , Esquizofrenia/genética , Esquizofrenia/fisiopatologia
2.
Cytopathology ; 16(3): 132-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15924608

RESUMO

INTRODUCTION: Previous studies have suggested that galectin-3 immunohistochemistry may be useful in the fine needle aspiration (FNA) diagnosis of thyroid carcinoma as it has been reported to selectively stain carcinomas and not adenomas or goitres. METHODS: Fifty-one patients were included in a prospective study of galectin-3 in thyroid FNA; 88.2% were female and 11.8% male, mean age 53 years, range 25-87 years. Cell blocks were prepared and stained for galectin-3 if any cells were present in needle washings from the respective FNAs. RESULTS: Twelve of 51 (23.5%) of cell blocks contained epithelial cells. One benign and one inadequate FNA were negative for galectin-3 staining. One of five non-diagnostic FNA cases, a papillary carcinoma on final histology showed positive staining. Four follicular neoplasm/suspicious of carcinoma cases showed negative staining. One malignant FNA case, a papillary carcinoma showed positive staining with galectin-3 but three further carcinomas, two papillary and one follicular were galectin-3 negative. CONCLUSION: Galectin-3 immunohistochemistry does not appear to be a useful adjunct to diagnosis in thyroid FNA as it does not reliably distinguish malignant and benign lesions. Many thyroid aspirates are of low cellularity and are not suitable for cell block immunohistochemistry.


Assuntos
Carcinoma Papilar/patologia , Galectina 3 , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/metabolismo , Feminino , Galectina 3/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/metabolismo
3.
Am J Vet Res ; 62(10): 1519-24, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11592313

RESUMO

OBJECTIVE: To evaluate viral and bacterial respiratory pathogens and Mycoplasma spp isolated from lung tissues of cattle with acute interstitial pneumonia (AIP) and cattle that had died as a result of other causes. SAMPLE POPULATION: 186 samples of lung tissues collected from cattle housed in 14 feedlots in the western United States. PROCEDURE: Lung tissues were collected during routine postmortem examination and submitted for histologic, microbiologic, and toxicologic examinations. Histologic diagnoses were categorized for AIP, bronchopneumonia (BP), control samples (no evidence of disease), and other disorders. RESULTS: Cattle affected with AIP had been in feedlots for a mean of 1272 days before death, which was longer than cattle with BP and control cattle. Detection of a viral respiratory pathogen (eg, bovine respiratory syncytial virus [BRSV], bovine viral diarrhea virus, bovine herpesvirus 1, or parainfluenza virus 3) was not associated with histologic category of lung tissues. Bovine respiratory syncytial virus was detected in 8.3% of AIP samples and 24.0% of control samples. Histologic category was associated with isolation of an aerobic bacterial agent and Mycoplasma spp. Cattle with BP were at greatest risk for isolation of an aerobic bacterial agent and Mycoplasma spp. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of these results suggests that AIP in feedlot cattle is not a consequence of infection with BRSV. The increased, risk of isolation of an aerobic bacterial agent from cattle with AIP, compared with control cattle, may indicate a causal role or an opportunistic infection that follows development of AIP.


Assuntos
Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/virologia , Doenças Pulmonares Intersticiais/veterinária , Pneumonia Bacteriana/veterinária , Animais , Broncopneumonia/epidemiologia , Broncopneumonia/veterinária , Broncopneumonia/virologia , Estudos de Casos e Controles , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Histocitoquímica/veterinária , Pulmão/microbiologia , Pulmão/patologia , Doenças Pulmonares Intersticiais/epidemiologia , Doenças Pulmonares Intersticiais/microbiologia , Doenças Pulmonares Intersticiais/virologia , Masculino , Mycoplasma/isolamento & purificação , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/veterinária , Pneumonia Bacteriana/epidemiologia , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/virologia , Estudos Prospectivos , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/veterinária , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Bovino/isolamento & purificação , Estados Unidos/epidemiologia
4.
Am J Vet Res ; 62(10): 1525-30, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11592314

RESUMO

OBJECTIVE: To compare concentrations of 3-methyleneindolenine (3MEIN) in lung tissues obtained from feedlot cattle that died as a result of acute interstitial pneumonia (AIP) and cattle that died as a result of other causes and to compare blood concentrations of 3MEIN in healthy feedlot cattle and feedlot cattle with AIP. STUDY POPULATION: Blood samples and lung tissues collected from 186 cattle housed in 14 feedlots in the western United States. PROCEDURE: Samples of lung tissues were collected during routine postmortem examination and submitted for histologic, microbiologic, and toxicologic examination. Blood samples were collected from cattle with clinical manifestations of AIP and healthy penmates. Histologic diagnoses were categorized as AIP, bronchopneumonia (BP), control samples, and other disorders. Concentrations of 3MEIN were determined in lung tissues and blood samples, using an ELISA. RESULTS: Concentrations of 3MEIN in lung tissues were significantly greater in AIP and BP samples, compared with control samples. Absorbance per microgram of protein did not differ between BP and AIP samples. Blood concentrations of 3MEIN were significantly greater in cattle with AIP, compared with healthy cattle or cattle with BP. Odds of an animal with AIP being a heifer was 3.1 times greater than the odds of that animal being a steer. CONCLUSIONS AND CLINICAL RELEVANCE: Increased pulmonary production of 3MEIN may be an important etiologic factor in feedlot-associated AIP.


Assuntos
Broncopneumonia/veterinária , Doenças dos Bovinos/metabolismo , Indóis/metabolismo , Doenças Pulmonares Intersticiais/veterinária , Pulmão/metabolismo , Animais , Broncopneumonia/sangue , Broncopneumonia/metabolismo , Bovinos , Doenças dos Bovinos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Histocitoquímica/veterinária , Indóis/sangue , Doenças Pulmonares Intersticiais/sangue , Doenças Pulmonares Intersticiais/metabolismo , Masculino , Fatores Sexuais
5.
Aquat Toxicol ; 52(2): 157-76, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11164537

RESUMO

Laboratory experiments were conducted with male summer flounder to assess the value of selected measures of endocrine status in fish as indicators of exposure to endocrine-disrupting contaminants. Effects of 1,1,1-trichloro-2-(p-chlorophenyl)-2-(o-chlorophenyl) ethane (o,p'-DDT), octylphenol and 1,1-dichloro-2,2-bis (p-chlorophenyl) ethylene (p,p'-DDE) on hepatosomatic and gonadosomatic indices, plasma steroid hormone levels, vitellogenin production, and gonadal development were evaluated in laboratory-raised, juvenile male summer flounder. Flounder were injected twice with test chemical in a coconut oil carrier. Each chemical was tested at three different concentrations. Estrogenic (o,p'-DDT; octylphenol) and anti-androgenic (p,p'-DDE) chemicals were evaluated alone and in combination (octylphenol plus o,p'-DDT or p,p'-DDE). Additionally, some fish were treated with the natural ligand for the estrogen receptor, 17beta-estradiol. Blood and tissues from different fish in each treatment were sampled 4, 6 and 8 weeks after the first injection. Fish exposed to a combination of o,p'-DDT plus octylphenol were also sampled after 15 weeks. In all cases, responses of fish exposed to a test chemical were compared to control fish sampled at the same time. The following significant differences, relative to controls, were observed in at least one sampling time or at least one concentration of chemical. 17beta-Estradiol-treated flounder exhibited decreased gonadosomatic index (GSI), altered hepatosomatic index (HSI), elevated plasma estradiol, reduced plasma testosterone, and high levels of plasma vitellogenin. Fish treated with o,p'-DDT showed lower GSI, no change in HSI or plasma estradiol, depression of plasma testosterone, and induction of vitellogenesis. Octylphenol treatment resulted in lower GSI, no change in HSI, initially increased plasma estradiol and decreased testosterone, and no vitellogenin production. p,p'-DDE treatment did not significantly alter any indicator relative to controls. In experiments using combinations of chemicals, flounder receiving o,p'-DDT plus octylphenol had lower GSI after 8 weeks and elevated plasma estradiol after 15 weeks exposure. Fish treated with p,p'-DDE plus octylphenol for 8 weeks exhibited a significantly lower GSI. Overall, lower GSI and plasma testosterone levels, relative to controls, were consistent indicators of exposure to estrogenic chemicals in juvenile male flounder. No indicators were found that would identify exposure to the mammalian anti-androgen p,p'-DDE.


Assuntos
DDT/farmacologia , Diclorodifenil Dicloroetileno/farmacologia , Estrogênios não Esteroides/farmacologia , Linguado/fisiologia , Indicadores e Reagentes , Inseticidas/farmacologia , Animais , Estradiol/sangue , Fígado/química , Fígado/efeitos dos fármacos , Masculino , Razão de Masculinidade , Testosterona/sangue , Vitelogeninas/sangue
6.
Aquat Toxicol ; 51(4): 431-41, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11090901

RESUMO

Male summer flounder (Paralichthys dentatus) were given two injections (initially and 2 weeks later) of 17beta-estradiol (E2) totaling 0.2 (2 x 0.1), 2.0 (2 x 1.0) or 20.0 (2 x 10.0) mg E2/kg body weight. Blood and tissue samples were collected 4, 6 and 8 weeks after the initial injection in the (2 x 0.1) mg/kg treatment, 4, 6, 8, and 15 weeks after the first injection in the (2 x 1.0) mg/kg treatment and at 4 weeks only in the (2 x 10.0) mg/kg treatment. Five of the 12 fish injected twice with 10.0 mg/kg were moribund before the first sampling period. Circulating levels of vitellogenin (VTG) in the blood of all E2-injected fish from all treatments were comparable with those concentrations found in the blood of wild male carp (Cyprinus carpio) and walleye (Stezostedion vitreum) previously collected near a sewage treatment plant (0.1-10.0 mg VTG/ml plasma). Excessive hyalin material accumulated in the livers, kidneys and testes of the treated fish. A portion of that material was identified as VTG by immunohistochemistry. The accumulation of VTG, and possibly other estrogen-inducible proteins, resulted in hepatocyte hypertrophy, disruption of spermatogenesis, and obstruction or rupture of renal glomeruli.


Assuntos
Linguado/fisiologia , Vitelogeninas/toxicidade , Animais , Estradiol/toxicidade , Imuno-Histoquímica , Rim/patologia , Fígado/patologia , Masculino , Testículo/patologia
10.
Toxicol Appl Pharmacol ; 126(2): 338-44, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7516098

RESUMO

Many tumor-promoting chemicals inhibit gap junctional communication between cells. We investigated the possibility that antipromoting chemicals may act inversely and enhance gap junctional communication. The V79/metabolic cooperation assay is an in vitro test that measures gap junctional communication indirectly by determining the extent of metabolic cooperation between mutant and wild-type V79 Chinese hamster lung fibroblasts in culture. Six in vivo antipromoters (caffeine, 3-isobutyl-1-methylxanthine (IBMX), phenidone, dibromoacetophenone, tosylphenylalanine chloromethyl ketone (TPCK), and acetic acid) were tested in this assay to assess their effects on metabolic cooperation. Caffeine, IBMX, phenidone, and dibromoacetophenone had no effect on metabolic cooperation, while TPCK slightly inhibited metabolic cooperation in one V79 assay. Acetic acid appeared to facilitate metabolic cooperation. In tests where an antipromoter was combined with the established tumor promoter phorbol 12-myristate 13-acetate (PMA), acetic acid, caffeine, and IBMX counteracted PMA-induced inhibition of metabolic cooperation, while phenidone, dibromoacetophenone, and TPCK had little effect. These results indicate that some antipromoters interfere with the ability of a tumor-promoting chemical to inhibit metabolic cooperation and suggest that alteration of gap junctional communication can be a mechanism of antipromoter action.


Assuntos
Anticarcinógenos/farmacologia , Comunicação Celular/efeitos dos fármacos , Junções Comunicantes/efeitos dos fármacos , 1-Metil-3-Isobutilxantina/farmacologia , Acetatos/farmacologia , Ácido Acético , Acetofenonas/farmacologia , Animais , Ácido Araquidônico/metabolismo , Cafeína/farmacologia , Células Cultivadas , Cricetinae , Cricetulus , Inibidores de Lipoxigenase/farmacologia , Mutação/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Fosfolipases A/antagonistas & inibidores , Inibidores de Proteases/farmacologia , Pirazóis/farmacologia , Tosilfenilalanil Clorometil Cetona/farmacologia
11.
Chest ; 102(3): 960-3, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1516435

RESUMO

A case of severe constrictive pericarditis resulting from an indolent Pseudomonas aeruginosa infection of the automatic internal cardiac defibrillator is described. Total explanation of the device was attempted after nine months but was unsuccessful because of dense adhesions under the patch electrodes. The patient subsequently developed clinical and hemodynamic findings of constrictive pericarditis and a second desperate attempt to remove the patches resulted in operative death. Diagnostic modalities for detecting infection of the AICD are reviewed. As soon as there is infection involving any component, the entire lead system and pulse generator should be removed.


Assuntos
Cardioversão Elétrica/instrumentação , Marca-Passo Artificial , Pericardite Constritiva/microbiologia , Próteses e Implantes/efeitos adversos , Infecções por Pseudomonas/etiologia , Idoso , Humanos , Masculino , Infecções por Pseudomonas/cirurgia , Fatores de Tempo
12.
Carcinogenesis ; 12(7): 1293-9, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2070495

RESUMO

The in vitro V79/metabolic cooperation assay measures the extent of gap-junctional transfer of metabolites from wild-type to mutant V79 cells. The assay is currently being explored as a short-term test to screen for tumor promoting chemicals, many of which inhibit metabolic cooperation. In this study, the assay was used to determine whether chemical interactions affect detection of tumor promoters in mixtures and to investigate types of interactions that may occur between chemicals. Several two-chemical mixtures were examined. The effects of phorbol-12-myristate-13-acetate (PMA) and phorbol-12,13-dibutyrate, two inhibitors of metabolic cooperation that operate through the same receptor-mediated pathway, were additive at concentrations below the maximally effective concentrations of either. A summation effect was observed in mixtures of two other inhibitors of metabolic cooperation, the pesticide aldrin and the principal metabolite of sodium cyclamate, cyclohexylamine. Synergistic effects were noted when PMA was combined with either aldrin or cyclohexylamine, demonstrating that chemicals in a mixture may yield a much stronger response than expected based on individual chemical exposures. Interactions were also examined between PMA, aldrin, cyclohexylamine and 2,4-diaminotoluene, a chemical that appears to enhance metabolic cooperation. 2,4-Diaminotoluene reversed effects of all inhibiting chemicals to some extent, although the pattern of response was different for each combination. In the most dramatic case, the powerful tumor promoter PMA was completely masked by 2,4-diaminotoluene. These results suggest that the V79/metabolic cooperation assay must be applied with caution in mixture testing because detection of tumor promoting chemicals can depend on other chemicals present.


Assuntos
Aldrina/farmacologia , Comunicação Celular/efeitos dos fármacos , Cicloexilaminas/farmacologia , Fenilenodiaminas/farmacologia , Dibutirato de 12,13-Forbol/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Células Cultivadas , Sinergismo Farmacológico , Proteína Quinase C/fisiologia
13.
Cell Biol Toxicol ; 5(2): 145-53, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2766028

RESUMO

Di(2-ethylhexyl)phthalate and trisodium nitrilotriacetate monohydrate, two apparently nongenotoxic carcinogens, were tested for effects on gap-junctional communication between Chinese hamster V79 lung fibroblasts. Both compounds inhibited gap-junctional communication in a concentration-dependent manner. The inhibiting effects of these chemicals on gap-junctional communication in vitro correlate with their tumor-promoting activity. Such results further support the hypothesis that inhibition of gap-junctional communication is an in vitro biomarker for some tumor-promoting chemicals.


Assuntos
Acetatos/farmacologia , Comunicação Celular/efeitos dos fármacos , Dietilexilftalato/farmacologia , Junções Intercelulares/efeitos dos fármacos , Ácido Nitrilotriacético/farmacologia , Ácidos Ftálicos/farmacologia , Animais , Testes de Carcinogenicidade/métodos , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Fibroblastos/efeitos dos fármacos , Técnicas In Vitro , Pulmão/citologia
15.
J Card Surg ; 1(4): 347-55, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2979930

RESUMO

Mitral annulus calcification is most often associated with myxomatous degeneration of the mitral valve. It is characterized by a horseshoe-shaped area of mitral annulus calcification that extends into the ventricular cavity to varying degrees. Standard suture techniques may be associated with fracture of the calcification and subsequent paravalvular leak. Seventeen patients aged 54 to 85 (mean 68.1) had mitral valve replacement using four techniques: suture through calcified annulus (3); decalcification (6); onlay patch (5); and drill technique (3). There were no hospital deaths, and one 81-year-old patient with associated coronary artery disease and ascending aortic calcification succumbed to a cerebrovascular accident three months postoperatively. The remaining patients are living and active with functional improvement. Follow-up has ranged from seven months to seven years with a mean of 4.0 years. One patient has hemodynamically insignificant mitral regurgitation after use of an onlay patch technique. No one technique could be singled out as clearly advantageous over the others from this series of patients.


Assuntos
Calcinose/cirurgia , Valva Mitral/cirurgia , Idoso , Idoso de 80 Anos ou mais , Calcinose/patologia , Feminino , Seguimentos , Doenças das Valvas Cardíacas/patologia , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/patologia , Insuficiência da Valva Mitral/cirurgia , Politetrafluoretileno , Complicações Pós-Operatórias , Próteses e Implantes , Propriedades de Superfície , Técnicas de Sutura
16.
Ann Thorac Surg ; 41(3): 276-83, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3954499

RESUMO

During a six-year period ending in December, 1980, 62 patients with a history or clinical evidence of corrosive ingestion were admitted into our institutions. The majority were adults who had attempted suicide. Strong alkali (lye), the most common corrosive agent involved, was ingested by more than half of the patients (39). The remaining 23 patients had ingested weak alkali or nonalkali corrosive agents. Of the 27 patients with severe esophagogastric burns (second- and third-degree), a 43.5% incidence overall, liquid lye was responsible in 21, including 7 of 8 patients with extensive full-thickness esophagogastric necrosis. In sharp contrast, only 1 of the 23 patients who had ingested weak alkali or nonalkali corrosive agents had serious esophagogastric injury. In the first two years of this review, the management approach was the so-called standard one (esophagoscopy, steroids, antibiotics, and dilation) (Group 1). The results were disappointing. In 5 of 9 patients with endoscopic findings of second-degree burns, stricture requiring dilation developed, and all 4 with extensive full-thickness esophagogastric necrosis died. In contrast, during the last four years, with the adoption of a more aggressive surgical approach, that is, early surgical intervention including the use of an intraluminal esophageal stent and radical resection as indicated, missed or delayed diagnosis of full-thickness esophagogastric necrosis with its prohibitive mortality was avoided and the complication of severe esophageal stricture was virtually eliminated (Group 2).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Queimaduras Químicas/cirurgia , Esôfago/lesões , Estômago/lesões , Adolescente , Adulto , Queimaduras Químicas/diagnóstico por imagem , Queimaduras Químicas/patologia , Criança , Pré-Escolar , Esofagoscopia , Esôfago/patologia , Esôfago/cirurgia , Gastroscopia , Humanos , Lactente , Lixívia/efeitos adversos , Radiografia , Estômago/patologia , Estômago/cirurgia
17.
Cell Biol Toxicol ; 1(4): 269-83, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3916985

RESUMO

The effect of phorbol myristate acetate, phorbol dibutyrate, ethanol, dimethylsulfoxide, phenol, and seven metabolites of phenol on metabolic cooperation were assessed as a function of mutant cell recovery from populations of cocultivated hypoxanthine-guanine phosphoribosyl transferase-deficient mutant (HGPRT-) and wild-type (HGPRT+) Chinese hamster V79 lung fibroblasts. Phorbol myristate acetate and phorbol dibutyrate, two established tumor promoters, were potent inhibitors of metabolic cooperation. Ethanol and dimethylsulfoxide, solvents commonly used to prepare chemicals for testing, weakly inhibited metabolic cooperation. Phenol and phenylglucuronide had no effect on metabolic cooperation. Four oxidative metabolites (1,4-benzoquinone, catechol, hydroxyquinol and quinol) inhibited metabolic cooperation. Phenylsulfate weakly inhibited metabolic cooperation. Conversely, 2-methoxyphenol, a methylated derivative of catechol, appeared to enhance metabolic cooperation. These results generally support the hypothesis that tumor promoters inhibit metabolic cooperation and illustrate the importance of considering metabolites when testing this hypothesis. The weak capacity of five metabolites of phenol to inhibit metabolic cooperation correlates with the weakness of phenol as a tumor promoter. Interpretation of these results is complicated because two metabolic cooperation-inhibiting metabolites (catechol and quinol) are nonpromoting when tested individually in the same assay where phenol shows promoting activity. Such metabolites may be incomplete (stage) promoters, and exposure to two or more may be required for a promoting effect. The significance of enhanced metabolic cooperation requires further investigation, particularly in relation to antipromoting effects.


Assuntos
Carcinógenos/farmacologia , Comunicação Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Animais , Células Cultivadas , Cricetinae , Cricetulus , Dimetil Sulfóxido/farmacologia , Etanol/farmacologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Pulmão/citologia , Pulmão/metabolismo , Fenol , Fenóis/farmacologia , Dibutirato de 12,13-Forbol/farmacologia , Acetato de Tetradecanoilforbol/farmacologia
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