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1.
Science ; 259(5092): 199-203, 1993 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-17790984

RESUMO

Evidence for five large earthquakes during the past five centuries along the San Andreas fault zone 70 kilometers northeast of Los Angeles, California, indicates that the average recurrence interval and the temporal variability are significantly smaller than previously thought. Rapid sedimentation during the past 5000 years in a 150-meter-wide structural depression has produced a greater than 21-meter-thick sequence of debris flow and stream deposits interbedded with more than 50 datable peat layers. Fault scarps, colluvial wedges, fissure infills, upward termination of ruptures, and tilted and folded deposits above listric faults provide evidence for large earthquakes that occurred in A.D. 1857, 1812, and about 1700, 1610, and 1470.

2.
Clin Cancer Res ; 6(7): 2931-40, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10914743

RESUMO

SU101 (leflunomide, N-[4-(trifluoromethyl)-phenyl] 5-methylisoxazole-4-carboxamide), an inhibitor of platelet-derived growth factor receptor signaling, has shown promising clinical activity in Phase I and II studies. Currently, SU101 in combination with cytotoxic agents is in late-stage clinical development for the treatment of cancers. In previous reports, efficacy in vivo versus varied tumor xenografts was observed. As part of the preclinical development of SU101 as a cancer therapy, the combination of SU101 with cytotoxic agents was studied in athymic mice bearing small, established, s.c. human tumor cell xenografts of glioblastoma (SF763T cells), lung (Calu-6 cells), or head and neck (KB cells) origin. In the SF763T model, the combination of SU101 with carmustine resulted in a statistically significant growth inhibition of 74% compared with the vehicle control; this combination was more effective than either agent alone. In the Calu-6 model, the combination of SU101, cisplatin, and etoposide resulted in a growth inhibition of 75% that was statistically greater than that of the vehicle-treated control group and groups treated with one or two agents. In the KB model, the combination of SU101, 5-fluorouracil, and cisplatin resulted in a statistically significant growth inhibition of 69% compared with the vehicle control. Treatment with one or two agents did not significantly inhibit growth in this model. Importantly, in addition to enhanced efficacy resulting from combination therapies, the combination treatments tested were well tolerated, as evidenced by lack of mortality. These data suggest that SU101 in combination with cytotoxic agents may provide clinical benefit and warrant further clinical investigation.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Glioblastoma/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Isoxazóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/toxicidade , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Carmustina/administração & dosagem , Carmustina/toxicidade , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/toxicidade , Etoposídeo/administração & dosagem , Etoposídeo/toxicidade , Humanos , Isoxazóis/administração & dosagem , Isoxazóis/toxicidade , Leflunomida , Camundongos , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Clin Cancer Res ; 3(7): 1167-77, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9815796

RESUMO

Many reports have cited coexpression of platelet-derived growth factor (PDGF) and its receptors by tumor cells or cells supporting tumor growth, suggesting both autocrine and paracrine mechanisms for PDGF-mediated tumor growth. We found that a small organic molecule, N-[4-(trifluoromethyl)phenyl] 5-methylisoxazole-4-carboxamide (SU101, leflunomide), inhibited PDGF-mediated signaling events, including receptor tyrosine phosphorylation, DNA synthesis, cell cycle progression, and cell proliferation. SU101 inhibited PDGF-stimulated tyrosine phosphorylation of PDGF receptor (PDGFR) beta in C6 (rat glioma) and NIH3T3 cells engineered to overexpress human PDGFRbeta (3T3-PDGFRbeta). SU101 blocked both PDGF- and epidermal growth factor (EGF)-stimulated DNA synthesis. Previously, this compound was shown to inhibit pyrimidine biosynthesis by interfering with the enzymatic activity of dihydroorotate dehydrogenase. In the current study, EGF-stimulated DNA synthesis was restored by the addition of saturating quantities of uridine, whereas PDGF-induced DNA synthesis was not, suggesting that the compound demonstrated some selectivity for the PDGFR pathway that was independent of pyrimidine biosynthesis. Selectivity was further demonstrated by the ability of the compound to block the entry of PDGF-stimulated cells into the S phase of the cell cycle, without affecting cell cycle progression of EGF-stimulated cells. In cell growth assays, SU101 selectively inhibited the growth of PDGFRbeta-expressing cell lines more efficiently than it inhibited the growth of PDGFRbeta-negative cell lines. SU101 inhibited the s.c., i.p., and intracerebral growth of a panel of cell lines including cells from glioma, ovarian, and prostate origin. In contrast, SU101 failed to inhibit the in vitro or s.c. growth of A431 and KB tumor cells, both of which express EGF receptor but not PDGFRbeta. SU101 also inhibited the growth of D1B and L1210 (murine leukemia) cells in syngeneic immunocompetent mice, without causing adverse effects on the immune response of the animals. In an i.p. model of tumor growth in syngeneic immunocompetent mice, SU101 prevented tumor growth and induced long-term survivors in animals implanted with 7TD1 (murine B-cell hybridoma) tumor cells. Because PDGFRbeta was detected on most of the tumor cell lines in which in vivo growth was inhibited by SU101, these data suggest that SU101 is an effective inhibitor of PDGF-driven tumor growth in vivo.


Assuntos
Glioma/patologia , Inibidores do Crescimento/toxicidade , Isoxazóis/toxicidade , Isoxazóis/uso terapêutico , Neoplasias Ovarianas/patologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Neoplasias da Próstata/patologia , Receptores do Fator de Crescimento Derivado de Plaquetas/fisiologia , Transdução de Sinais/efeitos dos fármacos , Células 3T3 , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Sobrevivência Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Feminino , Glioma/tratamento farmacológico , Inibidores do Crescimento/uso terapêutico , Humanos , Leflunomida , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Neoplasias Ovarianas/tratamento farmacológico , Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Fator de Crescimento Derivado de Plaquetas/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Ratos , Receptor beta de Fator de Crescimento Derivado de Plaquetas , Receptores do Fator de Crescimento Derivado de Plaquetas/efeitos dos fármacos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transfecção , Transplante Heterólogo , Células Tumorais Cultivadas
4.
Clin Neurophysiol ; 114(3): 438-49, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12705424

RESUMO

OBJECTIVE: Our main goal was to evaluate the accuracy of an original non-supervised spatio-temporal magnetoencephalography (MEG) localization method used to characterize interictal spikes generators. METHODS: MEG and stereotactic intracerebral recordings (stereo-electro-encephalographic exploration, SEEG) data were analyzed independently in 4 patients. MEG localizations were performed with and without anatomical constraints. RESULTS: We analyzed 1326 interictal spikes recorded using MEG. For each patient, 2-3 typical source patterns were described. These source configurations were compared with SEEG. SEEG findings and MEG spatio-temporal localization results were remarkably coherent in our 4 patients. Most of the MEG patterns were similar to interictal SEEG patterns from a spatio-temporal point of view. CONCLUSIONS: We were able to evaluate the usefulness of our non-invasive localization method. This approach described correctly the part of the epileptogenic network involved in the generation of interictal events. Our results demonstrate the potential of MEG in the non-invasive spatio-temporal characterization of generators of interictal spikes.


Assuntos
Eletroencefalografia/métodos , Epilepsia/diagnóstico , Magnetoencefalografia/métodos , Adolescente , Adulto , Eletrodos Implantados , Estudos de Avaliação como Assunto , Humanos , Modelos Neurológicos , Técnicas Estereotáxicas
5.
Psychiatr Clin North Am ; 13(3): 401-14, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2235690

RESUMO

This article is an exploration of intrapsychic structure formation and change from the point of view of a psychoanalytic concept of action. It compares the normal development of intrapsychic structure with that involved in psychotic disorganization as individuals encounter adolescence and its developmental tasks and requirements for action. The flexible complexity of intrapsychic structure and available action in a normally developing adolescent and the contrasting fixed simplicity of intrapsychic structure and its repertory of action in psychotic patients are highlighted. Four different environmental life occasions, all of which are associated with intrapsychic change, are examined against this background. The first of these involves little initial action on the part of the ego, although lasting change does occur. The last three involve both inner and outer developmental actions that can be central to growth and may be the occasion of psychosis. The first environmental life occasion is "trauma," in which the person's action, potentialities, and intrapsychic structure are disrupted by the world's destructive action and are thereby changed. The second is "intimacy," in which newly evolved actions and interaction are sought, often with little regard for or knowledge of the accompanying necessities of intrapsychic change. In the third --"success"--new intrapsychic change and altered necessities of action can surprisingly affect both the sense of continuity within one's inner world and the nature of one's relationship to the action of the outer world. The fourth occasion is "analytic" therapy, in which the regularities of one's intrapsychic structure and its stereotypies of action are often disrupted by the very "therapeutic" processes that allow these to be observed and examined in the course of promoting progressive development. All of these exciting and dangerous occasions mark out a separate, autonomous, individual, chosen act. The attempt to explicate the role of action in intrapsychic structural change during analytic work with a psychotic patient defines the analyst's actions as interferences and disruptions of that inner structure. His actions are noted, felt, represented, and organized into a part of that reformed, newly organized inner structure. Those analytic actions are represented by the patient as "having an impact" upon the patient and do indeed affect the patient. In that regard it is asserted that for a full, psychoanalytic conception of the ego, what is required is not only a central "body ego," but the integration of action in the formation and function of that ego's intrapsychic structure--an "action ego." Clarification of the complex relationship of conceptions of "fantasy" and action are re-examined in this context.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Desenvolvimento da Personalidade , Teoria Psicanalítica , Transtornos Psicóticos/psicologia , Adolescente , Ego , Humanos , Controle Interno-Externo , Terapia Psicanalítica , Transtornos Psicóticos/terapia
6.
J Pers Soc Psychol ; 51(2): 459-62, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3746627

RESUMO

We conducted this experiment to compare the task performance of Type A and Type B persons following failure on a task in which no one succeeded (universal failure) versus failure on a task in which others had succeeded (personal failure). Postfailure performance was measured in terms of speed of completion of anagrams. Initial analyses indicated that the failure manipulation was effective in influencing the subjects' perceived cause of their failures, and that subjects were more anxious and depressed following personal failure than universal failure. More important, we found that Type A subjects performed better following personal rather than universal failure, whereas type of failure had no effect on the performance of Type B subjects. The results suggest that contrary to what is usually thought, Type A persons do not struggle for success indiscriminately. The results are discussed in terms of need for control and self-esteem.


Assuntos
Personalidade Tipo A , Logro , Sintomas Afetivos/psicologia , Retroalimentação , Feminino , Humanos , Masculino , Esforço Físico
7.
Spine (Phila Pa 1976) ; 12(8): 787-91, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2961092

RESUMO

The development of a new scale, the Somatic Amplification Rating Scale (SARS), for the quantification of exaggerated (nonorganic) motor, sensory, and pain responses occurring during a standardized physical examination is described. This 13-item scale, partially based on a measure of nonorganic physical signs developed by Waddell et al, was administered to 127 low-back pain patients at an outpatient pain center. It was determined that the 13-item scale could be shortened to seven items with improved ease of administration and little loss of reliability and validity. Interrater reliability of the finalized seven-item scale was excellent (R = 0.93). Finally, it was determined that patients with high SARS scores were significantly more likely to be receiving workers' compensation benefits and to endorse physical symptoms with greater intensity on psychologic testing (Symptom Checklist 90).


Assuntos
Dor nas Costas/fisiopatologia , Medição da Dor/métodos , Exame Físico/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
8.
Lipids ; 12(10): 869-71, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27519629

RESUMO

The amount of butyrate contained in a complex mixture of butter oil triglycerides was 10.3 mole % as determined by natural abundance(13)C Fourier transform pulse nuclear magnetic resonance (NMR) spectroscopy. This NMR technique also demonstrated the primary isomeric positioning (>97%) of the butyrl group without the need for altering or fractionating the fat mixture.

9.
Lipids ; 27(4): 285-8, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1518386

RESUMO

Substitution of a hydroxyl group at the bis homoallylic position (OH group located three carbons away from the olefinic carbon) in C18 unsaturated fatty acid esters (FAE) induces a 0.73 +/- 0.05 ppm upfield and a 0.73 +/- 0.06 ppm downfield shift on the delta and epsilon olefinic 13C resonances relative to the unsubstituted FAE, respectively. If the hydroxyl group is located on the carboxyl side of the double bond of the bis homoallylic hydroxy fatty acid esters (BHAHFA), the olefinic resonances are uniformly shifted apart by [formula: see text] where delta delta dbu represents the absolute value of the double bond resonance separation in the unsubstituted FAE and 1.46 ppm is the sum of the absolute values of the delta and epsilon shift parameters. With hydroxyl substitution on the terminal methyl side of the double bond, the olefinic shift separation is equal to [formula: see text] In homoallylic (OH group located two carbons away from the olefinic carbon) substituted FAE the gamma and delta induced hydroxyl shifts for the cis double bond resonances are +3.08 and -4.63 ppm, respectively while the trans double bond parameters are +4.06 and -4.18 ppm, respectively. The double bond resonance separation in homoallylic hydroxy fatty acid esters (HAHFA) can be calculated from the formula [formula: see text] for cis and [formula: see text] for the trans case when the OH substitution is on the carboxyl side of the double bond. Conversely, when the OH resides on the terminal methyl side, the double bond shift separations for cis and trans isomers are [formula: see text] and [formula: see text] respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ácidos Graxos Insaturados/química , Algoritmos , Isótopos de Carbono , Ésteres , Espectroscopia de Ressonância Magnética
10.
J AOAC Int ; 78(4): 967-70, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7580337

RESUMO

Relatively simple and inexpensive procedures for screening milk for sulfamethazine (SMZ) and one of its metabolites, N4-acetylsulfamethazine (ASMZ), are detailed. Both methods detect at the low parts-per-billion level and are suitable for both field and laboratory use. Milk is passed over Chromosorb 102, which adsorbs SMZ. The drug is eluted and purified by direct passage of the effluent over small beds of buffered anion-exchange resins and alumina and is finally isolated and detected colorimetrically. For ASMZ, the procedure is modified so that SMZ is removed in the purification steps. The isolated ASMZ is then hydrolyzed to SMZ for detection. Application of the methods 5 years apart (1988 and 1993) shows that SMZ is still being used but to a lesser extent in 1993. Of over 250 samples screened in the 2 studies, only 2 were estimated to contain SMZ at 10 ppb, and the majority contained SMZ at 1 ppb. ASMZ was detected in a number of samples that were negative for SMZ.


Assuntos
Contaminação de Alimentos , Leite/química , Sulfametazina/análogos & derivados , Sulfametazina/análise , Animais , Análise de Alimentos/métodos , Sensibilidade e Especificidade
11.
J AOAC Int ; 76(2): 335-41, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8471859

RESUMO

Our earlier method to detect and quantitate sulfamethazine (SMZ) in milk at the 10 ppb level was modified to quantitate SMZ in pork tissue. Sulfabromomethazine (SBZ) is added to the tissue as an internal standard. SMZ and SBZ are extracted from the tissue into water as the supernatant of a centrifuged, aqueous homogenate and are cleaned up and concentrated by a series of solid-phase extractions. The sulfonamide-containing eluate is then separated on a silica gel thin-layer chromatographic plate. SBZ and SMZ are derivatized with fluorescamine, and their fluorescence is quantitated with a scanning densitometer. The limit of detection was estimated at 0.25 ppb (signal-to-noise ratio, 3:1). The average accuracy over the analysis range (0.54-21.8 ppb [micrograms/kg]) was 95.6% (standard deviation = 29.4%, n = 54).


Assuntos
Carne/análise , Sulfametazina/análise , Animais , Cromatografia em Camada Fina , Densitometria , Fluorescência , Sensibilidade e Especificidade , Suínos
12.
Meat Sci ; 40(2): 279-85, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-22059979

RESUMO

Finely ground chicken skin and subcutaneous fat exposed to gamma radiation from (137)Cs at 0-2°C for up to 10 kGy generated oxofatty acids (OFA) and hydroxyfatty acids (HFA) in the glycerides. Both classes were determined as colored derivatives; OFA as 2,4-dinitrophenylhydrazones, and HFA as esters of pyruvic acid 2,6-dinitrophenylhydrazone. The concentration of OFA increased with increasing irradiation dose but not always linearly. Variations in the concentration of both classes were noted and some chicken lipids failed to form both classes. In the samples where OFA were generated in significant quantities, the absorption maximum of the derivatives shifted toward a higher wavelength with increasing dose due ostensibly to the formation of double bond(s) in conjugation with the oxo group. This shift in absorption maximum was initially considered to be a means for detecting irradiation as well as indicating the dose received with fair accuracy. However, in several instances irradiation of a chicken sample did not result in the formation of significant increases in OFA and therefore this method cannot be used as a definitive test.

20.
J Assoc Off Anal Chem ; 65(3): 701-5, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-7096253

RESUMO

A simple, 10-min qualitative screening test for sulfamethazine (SM) in swine feeds is detailed. The method, which can be run in the field, uses 2 plastic tubes arranged piggyback style. The upper tube contains, from top to bottom, the feed sample (about 1 g), partially deactivated alumina, and an anion exchange resin buffered at pH 5.7. The bottom tube contains a small bed of anion exchanger buffered at pH 7.9, which traps the SM. After percolation of solvent from the pH 7.9 resin and is reacted with Bratton-Marshall reagents to give a pink-to-lavender color. Feeds containing less than or equal to 0.15 ppm can be detected. A simple, additional dye concentration step allows for detection of 0.02 ppm, if desired. Only amphoteric primary aromatic amino-containing compounds with a pKa close to that of SM can theoretically interfere. Preparation of permanent color solutions using cobalt and copper acetates in glacial acetic acid is described for the optional establishment of the minimum concentration of SM in the feed. The method offers a simple way to detect some cross-contaminated withdrawal feeds containing greater than 2 ppm SM, which can lead to violative (greater than or equal to ppm) residues in swine liver.


Assuntos
Ração Animal/análise , Aditivos Alimentares/análise , Sulfametazina/análise , Animais , Colorimetria , Suínos
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