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1.
Science ; 226(4676): 843-4, 1984 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-6494915

RESUMO

Sequence-dependent variations in DNA revealed by x-ray crystallographic studies have suggested that certain DNA-reactive drugs may react preferentially with defined sequences in DNA. Drugs that wind around the helix and reside within one of the grooves of DNA have perhaps the greatest chance of recognizing sequence-dependent features of DNA. The antitumor antibiotic CC-1065 covalently binds through N-3 of adenine and resides within the minor groove of DNA. This drug overlaps with five base pairs for which a high sequence specificity exists.


Assuntos
Antibióticos Antineoplásicos/metabolismo , Sequência de Bases , DNA/metabolismo , Indóis , Leucomicinas/metabolismo , Sítios de Ligação , Fenômenos Químicos , Química , Duocarmicinas , Conformação Molecular , Difração de Raios X
2.
Am J Primatol ; 70(7): 661-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18449883

RESUMO

Potential interactions between age and endocrinological functioning have been understudied in wild ape populations. Therefore, we examined the relationship between age and the secretion of androgens and glucocorticoids in 15 juvenile, subadult, and adult male chimpanzees (Pan troglodytes schweinfurthii) free ranging in the Budongo Forest of Uganda. One hundred and nine fecal samples were opportunistically collected, between 07:30 and 13:30 hr, during the wet season. Fecal samples were preserved, by oven drying, and steroid content extracted before radioimmunoassay for dehydroepiandrosterone-sulfate (DHEA-S), testosterone (TEST), cortisol (CORT), and corticosterone (CCT). Employing indexes of age as predictive factors, linear mixed-effects modeling and non-parametric statistical comparisons of fecal steroid levels were conducted. Age was observed to significantly influence the production of both glucocorticoids and androgens in male Budongo Forest chimpanzees. Basically, whereas TEST and CORT increased, DHEA-S and CCT levels slightly declined as animals matured.


Assuntos
Envelhecimento/fisiologia , Fezes/química , Hormônios Esteroides Gonadais/análise , Pan troglodytes/metabolismo , Animais , Feminino , Hormônios Esteroides Gonadais/metabolismo , Masculino , Uganda
3.
Cancer Res ; 47(23): 6384-7, 1987 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-3677083

RESUMO

Rat-1 and Rat-2 cells have been used in many studies of in vitro transformation and are widely assumed to be nontumorigenic because of their low incidence of focus formation, their poor growth in soft agar, and their reported failure to form tumors in animals. We examined more carefully the relationship between the in vitro and in vivo behavior of these cells and found that in spite of their in vitro characteristics, injection of these cells into Fischer rats invariably produced invasive tumors which frequently metastasized. When cells from primary tumors or metastases were cultured in vitro, the resultant cell lines were usually morphologically indistinguishable from parental cells and neither formed foci nor grew in soft agar. Thus, in vitro growth patterns do not correlate well with in vivo behavior in these cells and their inherent tumorigenicity warrants caution in the interpretation of results of in vitro transformation studies.


Assuntos
Transformação Celular Neoplásica , Metástase Neoplásica , Animais , Linhagem Celular , Fibroblastos/citologia , Cariotipagem , Camundongos , Camundongos Nus , Invasividade Neoplásica , Ratos , Ratos Endogâmicos F344
4.
Oncogene ; 1(3): 323-30, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3330778

RESUMO

We constructed fusion genes consisting of the mouse metallothionein I (MT) 5' region and the coding region of either the human H-ras gene (c-rasP3) or a mutated allele (c-rasT24); both ras genes lacked the initial (non-coding) exon and the first 30 bp of the non-coding region of the second exon. Transfection of Rat-1 cells produced foci only with pMT-rasT24, and selection in soft agar yielded clones in which MT-rasT24 expression was zinc-regulatable. In response to increasing concentrations of ZnSO4, these lines showed increasingly altered morphology (conversion to fusiform or spheroidal morphology), progressively higher maximal cell density, and an increasingly greater fraction of cells in the S + G2 + M portion of the cell cycle at high density. MT-rasT24 RNA levels in zinc-responsive lines were increased between 4- and 6-fold by the addition of ZnSO4 (final concentration = 100 microM) to the medium. Replating cells in the absence of zinc reversed the biological effects and resulted in reduction in MT-rasT24 RNA levels. Thus, graded alterations in phenotype result from increasing levels of MT-rasT24 gene expression.


Assuntos
Ciclo Celular , Diferenciação Celular , Genes ras , Proteínas Proto-Oncogênicas/fisiologia , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Metalotioneína/genética , Ratos , Transcrição Gênica/efeitos dos fármacos , Transfecção , Zinco/farmacologia
5.
J Clin Oncol ; 6(7): 1125-33, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3392561

RESUMO

Clinical and histopathologic data from 87 patients with primary non-Hodgkin's lymphoma of the gastrointestinal (GI) tract diagnosed between 1974 and 1984 were reviewed. B-cell lymphomas of intermediate- or high-grade histology constituted 78% of lesions. Stage of disease varied with histologic grade, with a preponderance of advanced disease (stages IIIE and IV) in patients with low-grade lymphoma (15 of 21) (71%), compared with higher grade lesions (38%, P = .01). Among patients with nonlocalized (stages IIE through IV) lymphoma of intermediate- or high-grade histology, surgical resection of the primary focus afforded a higher rate of complete remission (CR) (70% v 50%) and sustained CR (61% v 21%, P = .04) after cytotoxic therapy compared with the nonresected cohort. The median survival in the resected group was 51 months + compared with 13 months in the nonresected patients (P = .012). Differences in outcome were attributable to a high risk of treatment-related complications (perforation and/or hemorrhage) (43% v 0%, P = .001) and local relapse (29% v 4%, P = .05) in nonresected individuals. Life-threatening local complications were not observed in patients with low-grade lymphoma managed solely with medical therapy. Histologic findings from surgically staged patients identified presence of extravisceral disease and intermediate- or high-grade tumor histology as features predictive of transmural invasion, enabling potential identification of patients who might be optimally managed by resection of the primary GI focus before initiation of cytotoxic therapy.


Assuntos
Neoplasias Gastrointestinais/patologia , Linfoma não Hodgkin/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Terapia Combinada , Neoplasias Gastrointestinais/imunologia , Neoplasias Gastrointestinais/mortalidade , Neoplasias Gastrointestinais/terapia , Humanos , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/mortalidade , Linfoma não Hodgkin/terapia , Pessoa de Meia-Idade , Fenótipo , Complicações Pós-Operatórias/epidemiologia , Prognóstico
6.
BJR Case Rep ; 1(3): 20150017, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-30363658

RESUMO

Pseudoangiomatous stromal hyperplasia (PASH) is a benign breast disorder with the tumoral variety being extremely rare. We report a rare case of synchronous, massive axillary and breast tumoral PASH in a 55-year-old post-menopausal woman. Mammography, ultrasonography and sonoelastography features are illustrated with histopathological correlation. A high-grade invasive ductal carcinoma was detected in the contralateral breast on annual follow-up imaging. Radiologists need to be familiar with the imaging appearances of PASH and be aware of its association with subsequent cancer risk. To the best of our knowledge, the present case of synchronous tumoral PASH in the breast and axillary tissue is the second reported case till now.

7.
Am J Psychiatry ; 155(12): 1733-9, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9842784

RESUMO

OBJECTIVE: The purpose of this study was to assess the lifetime rates of occurrence of a full range of DSM-III-R axis I disorders in a group of patients with criteria-defined borderline personality disorder and comparison subjects with other personality disorders. METHOD: The axis I comorbidity of 504 inpatients with personality disorders was assessed by interviewers who were blind to clinical diagnosis and who used a semistructured research interview of demonstrated reliability. RESULTS: Four new findings emerged from this study. First, anxiety disorders were found to be almost as common among borderline patients (N=379) as mood disorders but far more discriminating from axis II comparison subjects (N=125). Second, posttraumatic stress disorder (PTSD) was found to be a common but not universal comorbid disorder among borderline patients, a finding inconsistent with the view that borderline personality disorder is actually a form of chronic PTSD. Third, male and female borderline patients were found to differ in the type of disorder of impulse in which they "specialized." More specifically, substance use disorders were significantly more common among male borderline patients, while eating disorders were significantly more common among female borderline patients. Fourth, a lifetime pattern of complex comorbidity (i.e., met DSM-III-R criteria for both a disorder of affect and a disorder of impulse at some point before the patients' index admission) was found to have strong positive predictive power for the borderline diagnosis as well as a high degree of sensitivity and specificity. CONCLUSIONS: These results suggest that the lifetime pattern of axis I comorbidity characteristic of borderline patients and distinguishing for the disorder is a particularly good marker for borderline personality disorder.


Assuntos
Transtorno da Personalidade Borderline/epidemiologia , Transtornos Mentais/epidemiologia , Adolescente , Adulto , Transtornos de Ansiedade/epidemiologia , Comorbidade , Transtorno Depressivo/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos da Personalidade/epidemiologia , Prevalência , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Psicometria , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores Sexuais , Transtornos Somatoformes/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
8.
Mol Biochem Parasitol ; 51(2): 209-18, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1574079

RESUMO

Three new members of a developmentally regulated cysteine protease gene family of the parasitic nematode Haemonchus contortus have been isolated and characterized. One of the new genes, AC-3, was found to be linked in tandem to the previously characterized AC-2 gene. Nucleotide sequence analyses revealed that the first 90 amino acids of AC-3 are organized into four exons, similar to the situation in AC-2. A cDNA that appears to be a near full-length copy of the AC-3 gene was isolated using the polymerase chain reaction (PCR) technique to amplify cDNAs from adult worm poly(A)+ mRNAs. In addition to AC-3, a distinct cysteine protease cDNA, AC-4, was amplified by the same oligonucleotide primers. cDNAs encoding a fifth cysteine protease, AC-5, were isolated from an adult worm cDNA expression library using specific rabbit antisera and by PCR. Comparison of the predicted amino acid sequences of AC-3, AC-4 and AC-5 reveal that they share 64-77% identity with one another and with the previously reported AC-1 and AC-2 sequences. The amino acids surrounding the active site cysteine are highly conserved, as are the positions of other cysteine residues in the mature protein sequences. The H. contortus proteases are more similar to one another than they are to human cathepsin B (38-44% amino acid identity) or to the Sm31 cysteine protease of Schistosoma mansoni (36-40% identity). Our studies indicate that H. contortus adult worms express mRNAs for several distinct cysteine proteases. The significant primary sequence differences between the proteases suggest that they differ in their substrate specificities and precise physiological functions.


Assuntos
Cisteína Endopeptidases/genética , Haemonchus/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Cisteína Endopeptidases/metabolismo , DNA , Fibrinogênio/metabolismo , Expressão Gênica , Ligação Genética , Haemonchus/enzimologia , Dados de Sequência Molecular , Família Multigênica , Mapeamento por Restrição , Alinhamento de Sequência
9.
Arch Surg ; 114(2): 214-5, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-371583

RESUMO

Acute obstructive cholangitis developed secondary to a common duct stone formed around a silver hemostatic clip, introduced at cholecystectomy two years previously, that had migrated from a long cystic duct remnant. Stone formation around a silk suture is well known, and silver clips in the area of the porta hepatis may constitute a similar hazard.


Assuntos
Colangite/etiologia , Colecistectomia/efeitos adversos , Corpos Estranhos/complicações , Migração de Corpo Estranho/complicações , Cálculos Biliares/etiologia , Colangiografia , Colangite/diagnóstico , Colangite/cirurgia , Colecistite/cirurgia , Endoscopia , Feminino , Cálculos Biliares/cirurgia , Humanos , Pessoa de Meia-Idade , Prata , Instrumentos Cirúrgicos
10.
Arch Surg ; 127(10): 1254-5, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1417496

RESUMO

We report a case of tubular adenoma of the duct of Wirsung with focal villous changes. To our knowledge, this is the 13th reported case of this uncommon neoplasm and the first with a primarily tubular histologic pattern. The patient presented with abdominal pain and diarrhea and was found on endoscopic retrograde cholangiopancreaticography to have a mass in the head of the pancreas, which was confirmed by endoscopic ultrasound. Clinical and pathological features of the 12 previously reported cases are reviewed. Intraoperative testing failed to rule out adenocarcinoma which, in addition to difficulties presented by local anatomic relationships of the tumor, supports wide surgical resection as the preferred surgical solution.


Assuntos
Adenoma/patologia , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/patologia , Idoso , Diagnóstico Diferencial , Técnicas de Diagnóstico por Cirurgia , Feminino , Humanos
11.
Environ Mol Mutagen ; 36(1): 13-21, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10918355

RESUMO

Octamethylcyclotetrasiloxane (OMCTS; CAS No. 556-67-2) was evaluated in a genetic toxicity battery. In preincubation tests with Salmonella typhimurium strains TA98, TA100, TA1535, TA1537, and TA1538, no mutagenicity was detected (maximum dose = 5 mg/plate) with or without S9 in two independent trials. Treatment of cultured Chinese hamster ovary (CHO) cells was limited by cytotoxicity at OMCTS concentrations greater than 0.003 mg/mL without S9 and 0.03 mg/mL with S9. CHO cells treated with up to 0.003 mg/mL without S9 and 0.03 mg/mL with S9 showed no significant dose-related increases in chromosomal aberration frequencies. No significant dose-related increases in sister chromatid exchanges (SCEs) occurred in OMCTS-treated CHO cells (maximum OMCTS concentration = 0.003 mg/mL without S9; 0.03 mg/mL with S9). Therefore, OMCTS was concluded to be negative in the SCE assay. In a screen for in vivo clastogenic potential, Sprague-Dawley rats received 700 ppm OMCTS by whole-body vapor inhalation 6 hr daily for 5 days. A negative control group received filtered air on the same schedule. A positive control group was exposed to filtered air on the same schedule and received cyclophosphamide 24 hr before termination. The OMCTS-treated animals were terminated 6 and 24 hr after the final exposure. Positive and negative control animals were terminated 24 hr after the last exposure. No significant, treatment-related increases in chromosomal aberrations were detected. The results of these studies indicate that OMCTS does not possess significant in vitro genotoxic potential. No adverse genetic findings were seen in the in vivo screen for chromosome aberrations.


Assuntos
Adjuvantes Imunológicos/toxicidade , Testes de Mutagenicidade/métodos , Siloxanas/toxicidade , Animais , Medula Óssea/efeitos dos fármacos , Células CHO/efeitos dos fármacos , Aberrações Cromossômicas , Cricetinae , Feminino , Masculino , Ratos , Ratos Sprague-Dawley , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Troca de Cromátide Irmã
12.
Am J Surg ; 163(3): 305-11, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1539764

RESUMO

The clinical value of fine needle aspiration (FNA) of the breast is enhanced by incorporating into the cytologic diagnosis explicit comments on the level of diagnostic certainty. This stratification of diagnostic certainty is based predominantly on the cytologic features but occasionally also takes into consideration the clinical situation. Strong clinical and mammographic suspicion of mammary carcinoma associated with FNA, diagnostic of typical, intermediate to high-grade mammary carcinoma, warrants proceeding to definitive therapy without further diagnostic studies. False-positive results are virtually eliminated by placing cases with any uncertainty into a "probable" category, which does not support definitive therapy. In addition, oversimplified "benign versus malignant" approaches to FNA diagnoses ignore the heterogeneity of breast masses, with in situ and low-grade carcinomas warranting special clinical management and usually being placed in the "probable" category. Thus, malignant diagnoses are stratified into "definite" and "probable," with only the former supporting definitive therapy. Within our recent series of 1,005 FNAs of the breast, we were able to confirm the diagnosis in all 62 patients with a "definite" carcinoma diagnosis, and only 3 of 25 "probable" cancer diagnoses were benign at tissue biopsy. Thus, false-positive results were successfully avoided in the "definite" category. Furthermore, a much greater incidence of unusual and good prognosis tumor types were identified by the "probable" category. If the clinical setting is relatively suspicious only, a definitive diagnosis of cancer by FNA is rare and not necessary because the clinical question to be addressed is only whether to biopsy. This approach to FNA diagnosis, unlike the oversimplified "benign versus malignant" scheme, provides an approach that is more likely to result in optimal therapy for breast neoplasms, with low-grade or in situ carcinomas requiring special clinical management since these types of cancers are found predominantly in the "probably malignant" category. It also provides additional security against false-positive diagnoses by incorporating clinical level of certainty statements into FNA diagnostic categories, which more closely reflect the diversity and inherent complexity in the appropriate diagnosis and therapy of mammary carcinomas.


Assuntos
Biópsia por Agulha , Neoplasias da Mama/diagnóstico , Mama/patologia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Citodiagnóstico , Feminino , Humanos
13.
Chem Biol Interact ; 42(2): 141-51, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7151226

RESUMO

The reaction of anthramycin with DNA has been examined to determine the chemical identity of the adduct which forms in a living cell and to observe the effects of the nucleosome structure of chromatin on drug binding. The chemical identity of the cellular adduct was probed by comparing various properties of the cellular adduct to properties of the known, in vitro adduct. The effect of the histones on anthramycin binding was investigated by time-course binding reactions. Results indicate that the properties of the cellular anthramycin-DNA adduct are similar to the in vitro adduct. The histone proteins associated with DNA in chromatin were found to decrease both the reaction kinetics and the final levels of anthramycin binding. Anthramycin reacts appreciably with nucleosome core DNA, but appears to exhibit a preference for linker DNA.


Assuntos
Antramicina/metabolismo , Benzodiazepinonas/metabolismo , Cromatina/metabolismo , DNA de Cadeia Simples/metabolismo , Fibroblastos/metabolismo , Humanos , Cinética
14.
Oecologia ; 115(3): 331-336, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28308423

RESUMO

Fruits, leaves and bark forming part of the diet of chimpanzees were collected and it was noted whether samples were of a kind being eaten or not eaten. Samples were dried and analysed for condensed tannin content and for three sugars, glucose, sucrose and fructose. It was found that chimpanzees did not select foods according to the level of tannins but did so according to the levels of sugars, preferring the higher levels. Fig seeds contained higher tannin levels than fig pulp, and the chimpanzees made oral boli ("wadges") of fig seeds which they spat out. Two fig species were compared: the one with lower tannin and higher sugar content was preferred. The bark of one tree species often eaten contained high levels of tannins but also contained sugars. Young leaves with lower tannin levels were preferred to mature leaves with higher levels. Chimpanzees appear to be able to tolerate higher tannin levels than three monkey species in this forest, and considerably higher levels than marmosets (Callitrichidae).

15.
Reprod Toxicol ; 13(5): 383-90, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10560587

RESUMO

Anogenital distance (AGD) is an endpoint that was recently added to the U.S. EPA testing guidelines for reproductive toxicity studies. This endpoint is sensitive to hormonal effects of test chemicals. It is possible that apparent alterations in AGD might occur after treatment with agents that affect overall pup body size. In such cases, hormonal activity might be associated incorrectly with the test treatment. The analyses in this report evaluated statistical correlations between pup body weight and AGD in control litters. AGDs were measured on postnatal day 1 in 1501 pups derived from 113 untreated female Sprague-Dawley rats in two independent two-generation reproductive toxicity studies. Significant correlations were detected between AGD and body weight and between AGD and the cube root of body weight. In males, AGD increased 0.26 mm for each 1 g increase in body weight. In females, AGD increased 0.13 mm per 1 g increase in body weight. Although there were essentially no differences between the regression models developed to predict AGD in either males or females using body weight as a covariate and those based on the cube root of body weight, such similarities in predictivity might not occur in larger animals with broader weight ranges than those encountered in this analysis. Normalization of AGD by dividing by body weight significantly overcompensated for differences in body size. Normalizing with the cube root of body weight resulted in an AGD/cube root of body weight ratio that was constant across the range of body weights observed in this study. In conclusion, as a preferred method to account for body size effects on AGD, analysis of covariance is recommended. If a normalization is done directly, the ratio of AGD to the cube root of body weight is the more appropriate metric.


Assuntos
Peso Corporal/fisiologia , Fatores de Confusão Epidemiológicos , Desenvolvimento Embrionário e Fetal/fisiologia , Genitália Feminina/crescimento & desenvolvimento , Genitália Masculina/crescimento & desenvolvimento , Diferenciação Sexual/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Análise de Regressão , Testes de Toxicidade/métodos
16.
Mutat Res ; 321(1-2): 43-56, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7510844

RESUMO

Benomyl (methyl [1-[(butylamino)carbonyl]-1H-benzimidazol-2- yl]carbamate) and its major metabolite carbendazim (methyl 2-benzimidazolecarbamate) are major agricultural systemic fungicides. These compounds inhibit fungal microtubular function and thereby cause nondisjunction of chromosomes at cell division. Several investigators have proposed that these compounds can also cause gene mutations (base-pair substitutions). In this laboratory, no mutagenic activity was observed with either benomyl (analytical grade) or Benlate (samples tested up to 500 and 1200 micrograms/plate, respectively, the limit of cytotoxicity) in the Salmonella/Ames plate-incorporation test in either base-pair substitution (TA100 and TA1535) or frameshift-sensitive (TA98 and TA1537) strains with or without S9 metabolic activation. However, some carbendazim preparations caused mutations in frameshift-sensitive strains at very high concentrations (> or = 5000 micrograms/plate) with metabolic activation. The mutagenic activity was not due to the major carbendazim metabolite, methyl (5-hydroxy-1H-benzimidazol-2-yl)carbamate (5-OH MBC), since 5-OH MBC was not mutagenic with (up to 20,000 micrograms/plate) or without (up to 16,000 micrograms/plate) activation. Subsequently, two highly mutagenic contaminants, 2,3-diaminophenazine (DAP) and 2-amino-3-hydroxyphenazine (AHP) were detected in mutagenic carbendazim samples. In those samples, DAP and AHP contaminant levels ranged as high as 46.5 and 11.6 ppm, respectively. No evidence of mutagenicity could be detected in preparations in which the DAP content was < 1.8 ppm. The mutagenic activity of these two contaminants was further investigated in strain TA98. Without activation, DAP and AHP were positive at test concentrations as low as 5 and 10 micrograms/plate, respectively. In the presence of S9, mutations were detected at much lower concentrations (beginning at 0.025 and 0.05 microgram/plate, respectively). These results indicate that carbendazim samples containing DAP or AHP at levels as low as 5 or 10 ppm, respectively, would be positive in the Salmonella/Ames test with activation when tested at 5000 micrograms/plate. Purified carbendazim is not mutagenic.


Assuntos
Aminas/toxicidade , Benzimidazóis/toxicidade , Fungicidas Industriais/toxicidade , Mutagênicos/toxicidade , Fenazinas/toxicidade , Benomilo/toxicidade , Benzimidazóis/síntese química , Benzimidazóis/química , Biotransformação , Carbamatos/toxicidade , Mutação da Fase de Leitura , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Microssomos Hepáticos/enzimologia , Testes de Mutagenicidade , Mutagênicos/química , Fenazinas/síntese química , Fenazinas/química , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética
17.
Mutat Res ; 310(1): 143-9, 1994 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-7523878

RESUMO

Benomyl and its active metabolite carbendazim were investigated in BDF1 mouse bone marrow to establish whether micronuclei induced by these fungicides are caused by clastogenic or aneugenic events. Micronuclei were evaluated for kinetochores using immunofluorescent antikinetochore antibodies. Kinetochore positive (K+) micronuclei are likely to arise from chromosome loss since they presumably contain intact kinetochores and are indicative of aneuploidy. Conversely, kinetochore negative (K-) micronuclei are mostly likely to contain acentric chromosome fragments arising primarily from clastogenic damage. Benomyl and carbendazim were administered as single oral doses of 0.3, 8.6 or 17.2 mmol/kg (for benomyl, equivalent to 100, 2500 or 5000 mg/kg; for carbendazim, equivalent to 66, 1646 or 3293 mg/kg). Both compounds were positive in the micronucleus test at doses of 8.6 and 17.2 mmol/kg, and an average of 82% (benomyl) and 87% (carbendazim) of the total micronucleated polychromatic erythrocytes were K+. No effects were seen with either fungicide at 0.3 mmol/kg. These results are analogous to findings with known aneugens such as vincristine but are in contrast to results with classical clastogens such as cyclophosphamide. Thus, benomyl and carbendazim induce micronuclei in mouse bone marrow cells primarily through an aneugenic mechanism.


Assuntos
Benomilo/toxicidade , Benzimidazóis/toxicidade , Carbamatos , Mutagênicos/toxicidade , Aneuploidia , Animais , Medula Óssea/efeitos dos fármacos , Células da Medula Óssea , Feminino , Masculino , Camundongos , Testes para Micronúcleos
18.
Chronobiol Int ; 12(1): 37-45, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7750156

RESUMO

Minute-by-minute heart rate (HR) recordings over a period of 24 h were obtained once for 30 elderly subjects diagnosed as having senile dementia of Alzheimer type (SDAT). Twenty-one of the subjects were studied in a hospital ward setting, and nine were studied in their own homes. Twelve were men and 18 were women. Eleven took some form of sedative medication; 10 took no medication. Thirty-minute mean values were unmasked to take account of the effects of activity and sleep on HR. Results indicate that the masked HR circadian rhythm of SDAT may be more often unimodal than that of normal subjects of similar age, and that phase shift of the endogenous, clock-mediated component of the rhythm (with higher HR at night) is to be expected in a proportion of individuals with SDAT.


Assuntos
Doença de Alzheimer/patologia , Ritmo Circadiano , Frequência Cardíaca , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comportamento , Demência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Am Surg ; 56(4): 199-203, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2194410

RESUMO

Primary malignant melanoma of the adrenal gland is an established entity despite early doubts. It originates in the adrenal medulla from cells derivative of the neural crest. Because of the high frequency of metastatic involvement of the adrenal by cutaneous and ocular melanomas, rigid diagnostic criteria should be followed. Only four cases of this lesion have been reported since 1946. Review of these four together with the two described in this article shows that primary adrenal melanoma is a highly malignant tumor of middle age that often manifests as a painful flank mass. Distant lymph node metastases can be seen as a presenting sign. Treatment is not effective with a mortality rate approaching 100 per cent within two years. Since the true melanocytic origin of primary adrenal melanoma has not been established and because of the similarity of its pathologic findings with the pheochromocytomas, we believe that adrenal melanoma arises from the pheochromocytes and should be called "melanotic malignant pheochromocytoma."


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Melanoma/diagnóstico , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias das Glândulas Suprarrenais/patologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Feminino , Humanos , Metástase Linfática , Masculino , Melanoma/patologia , Melanoma/secundário , Melanoma/cirurgia , Pessoa de Meia-Idade , Neoplasias Primárias Desconhecidas/patologia , Neoplasias Primárias Desconhecidas/cirurgia
20.
Ann Dyslexia ; 37(1): 189-200, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24234994

RESUMO

This paper includes an overview of curriculum information and the basic techniques of a multisensory approach for teaching alphabet and dictionary skills, reading, spelling, and cursive handwriting. It also reports the results of a four-year study of reading and spelling in both remedial and nonremedial classes in a public school. The California Achievement Test (CAT) scores in reading and spelling for students in both remedial and nonremedial classes improved over baseline scores following this multisensory approach. Additionally, there was a tendency for the CAT mean scores to increase corresponding to the number of years students had been taught by the multisensory program.

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