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1.
Cancer Radiother ; 24(1): 53-59, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32046915

RESUMO

PUPOSE: To compare dosimetric plans for the treatments of oligobrains metastases (2-6) using mono-isocentric arc therapy and multi-isocentric volumetric modulated arc therapy (VMAT). MATERIAL AND METHODS: A total of sixteen patients with multiple brain metastases were selected. Prescription dose was between 24 and 15Gy depending on the tumor size. For every patient,arctherapy and VMAT plans were generated respectively, with Elements Multiple Brain Mets SRS version 2.0 (BrainLab) and Eclipse SRS Treatment Planning Systeme version 15.5. The conformity index (CI), homogeinity index (HI), gradient index (GI), dose volume histogram for each organs at risk, total Monitor Units were evaluated. RESULTS: For coverage of the PTV, mono-isocentric plans showed a better CI and a better GI than multi-isocentric plans, respectively CI of 1.18±0.11 vs 1.41±0.20 (P<0.01), and GI of 3.55±0.59 vs 4.03±1.20 (P<0.01). Homogeneity index was not better with mono-isocentric plans, with respectively HI 24.32±3.87 vs 14.05±4.46 (P=1). For organs at risk, there were no statistical differences between mono and multi-isocentric plans for both eyes, both lenses, both optic nerves, chiasma, brainstem, and hippocampi.V12Gy and V10Gy of normal brain were statistically lower with mono-isocentric plans than with multi-isocentric plans, respectivellyV12Gy of 3.06Gy 95%CI [2.25;3.86]vs 5.18Gy 95%CI [3.43;6.93] (P<0,01) and V10Gy 4.66Gy 95%CI [3.33;5.98] vs7.30Gy 95%CI [4.73;9.87] (P<0.03). Total number of MU was significantly lower with mono-isocentric plans than with multi-isocentric plans, respectively 6668±1463 vs 12403±4941 (P<0.01), then treatment time was lower with mono-isocentric plans. CONCLUSION: Mono-isocentric plans had a better conformity index and gradient index than multi-isocentric plans for the treatment of multiple brain metastases. Moreover, mono-isocentric techniques gave fewer doses to normal brain and used less monitor units than multi-isocentric techniques.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/efeitos da radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Planejamento da Radioterapia Assistida por Computador
2.
Int J Neurosci ; 127(12): 1082-1086, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28504037

RESUMO

Butyrylcholinesterase (BChE) is an enzyme encoded by BCHE gene, responsible for secondary hydrolysis of the acetylcholine. K and -116A BCHE variants were associated with decrease in plasma BChE activity, and their influence has been investigated in diseases with a cholinergic deficit such as Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). In order to check the influence of BCHE genetic variants on enzymatic activity, all patients and controls were genotyped for K and -116A variants. We found lower plasma BChE activity in DLB patients compared to elderly controls and to AD independent of the presence of K or -116A variants. Our results suggest that the reduction of total plasma BChE activity is probably associated with a feedback mechanism and provides a future perspective of using this enzyme as a possible plasmatic marker for differential diagnosis between AD and DLB.


Assuntos
Doença de Alzheimer/sangue , Butirilcolinesterase/sangue , Doença por Corpos de Lewy/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Butirilcolinesterase/genética , Diagnóstico Diferencial , Feminino , Genótipo , Humanos , Masculino
3.
Clin Pharmacol Ther ; 94(1): 158-66, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23588312

RESUMO

5-Fluorouracil (5-FU) is used to treat many aggressive cancers, such as those of the colon, breast, and head and neck. The responses to 5-FU, with respect to both toxicity and efficacy, vary among racial groups, potentially because of variability in the activity levels of the enzyme dihydropyrimidine dehydrogenase (DPD, encoded by the DPYD gene). In this study, the genetic associations between DPYD variations and circulating mononuclear-cell DPD enzyme activity were evaluated in 94 African-American and 81 European-American volunteers. The DPYD-Y186C variant was unique to individuals of African ancestry, and DPD activity was 46% lower in carriers as compared with noncarriers (279 ± 35 vs. 514 ± 168 pmol 5-FU min(-1) mg(-1); P = 0.00029). In this study, 26% of the African Americans with reduced DPD activity were carriers of Y186C. In the African-American cohort, after excluding Y186C carriers, homozygous carriers of C29R showed 27% higher DPD activity as compared with noncarriers (609 ± 152 and 480 ± 152 pmol 5-FU min(-1) mg(-1), respectively; P = 0.013).


Assuntos
Afro-Americanos/genética , Antimetabólitos Antineoplásicos/uso terapêutico , Di-Hidrouracila Desidrogenase (NADP)/genética , Fluoruracila/uso terapêutico , Neoplasias/tratamento farmacológico , Adulto , Estudos de Coortes , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Humanos , Masculino , Neoplasias/enzimologia , Adulto Jovem
4.
J Exp Biol ; 208(Pt 22): 4255-61, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16272248

RESUMO

A more medial and anterior position of the red aerobic myotomal muscle (RM) and the presence of a vascular counter-current heat exchange system provide the functional elements that facilitate regional RM endothermy in tunas, lamnid sharks and the common thresher shark (Alopias vulpinus). The convergent RM morphology among all species capable of RM endothermy suggests that RM position is a strong predictor of fish endothermic capacity. The present study investigated the comparative RM morphology of the other two thresher shark species (bigeye thresher, Alopias superciliosus, and the pelagic thresher, Alopias pelagicus), for which there is no information regarding their capacity for RM endothermy, and compared these data with published works on A. vulpinus. The digitization of transverse sections along the body of A. superciliosus and A. pelagicus enabled quantification of the relative amount of RM and the position and placement of the RM along the body. The RM in both A. superciliosus and A. pelagicus is positioned subcutaneously, along the lateral edges of the myotomes, and is distributed relatively evenly over the trunk of the body. The position of maximum RM area is at 50% fork length (FL) for A. superciliosus and at 75% FL for A. pelagicus. The amount of RM (mean +/- S.E.M.) is 2.31+/-0.11% and 3.01+/-0.10% in A. superciliosus and A. pelagicus, respectively. When compared with A. vulpinus, all three alopiid sharks have a similar amount of RM. However, A. superciliosus and A. pelagicus differ from A. vulpinus in that they do not possess the medial and anterior RM arrangement that would likely facilitate metabolic heat conservation (RM endothermy).


Assuntos
Regulação da Temperatura Corporal/fisiologia , Modelos Anatômicos , Fibras Musculares de Contração Rápida/citologia , Músculo Esquelético/anatomia & histologia , Tubarões/anatomia & histologia , Animais , Tamanho Corporal , Pesos e Medidas Corporais , Análise de Sequência de DNA , Tubarões/fisiologia , Especificidade da Espécie
5.
Am J Obstet Gynecol ; 184(6): 1074-6, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11349161

RESUMO

OBJECTIVE: Our purpose was to determine the utility of measuring serum leukemia inhibitory factor, a cytokine expressed in the process of pregnancy implantation, for the diagnosis of ectopic pregnancy. STUDY DESIGN: Serum samples from 40 patients with positive serum quantitative beta-human chorionic gonadotropin levels were used for leukemia inhibitory factor determination. The serum leukemia inhibitory factor concentration was determined by enzyme-linked immunosorbent assay in the following 4 groups: (1) normal intrauterine pregnancies, (2) threatened abortions, (3) spontaneous abortions, and (4) ectopic pregnancies. RESULTS: All patients had detectable concentrations of leukemia inhibitory factor in serum, ranging from 2.44 to 8.25 pg/mL. Mean leukemia inhibitory factor concentrations for ectopic pregnancy were significantly lower (P <.05) than those of both the spontaneous abortion and threatened abortion groups by 1-way analysis of variance. When a cutoff point of serum leukemia inhibitory factor <6.2 pg/mL is assigned as diagnostic of ectopic pregnancy, leukemia inhibitory factor in patients with ectopic pregnancies versus all other groups predicted ectopic pregnancy with a sensitivity of 73%, specificity of 72%, positive predictive value of 50%, and negative predictive value of 88%. CONCLUSION: Serum leukemia inhibitory factor concentration is lowest in patients with ectopic pregnancy. A cutoff point of 6.2 pg/mL maximizes the sensitivity and specificity of the test; however, it is not sufficiently discriminatory to be used clinically for the diagnosis of ectopic pregnancy.


Assuntos
Inibidores do Crescimento/sangue , Interleucina-6 , Linfocinas/sangue , Gravidez Ectópica/sangue , Gravidez Ectópica/diagnóstico , Aborto Espontâneo/sangue , Ameaça de Aborto/sangue , Biomarcadores , Feminino , Humanos , Fator Inibidor de Leucemia , Concentração Osmolar , Valor Preditivo dos Testes , Gravidez , Valores de Referência , Sensibilidade e Especificidade
6.
Int J Addict ; 18(2): 183-94, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6862736

RESUMO

On the basis of structured interview data concerning their life-styles, behaviors, circumstances, and activities during their most recent periods of addiction, 460 male narcotic addicts (230 Black and 230 White) were empirically classified, or "typed," using factor and cluster analytic techniques in a multistage process. Mean factor score profiles for each of the eight types derived are presented, along with provisional labels and verbal descriptions. It is believed that this classification is descriptive of the major addict types to be encountered in a large urban population.


Assuntos
Transtornos Relacionados ao Uso de Opioides/psicologia , Adulto , Afro-Americanos , Grupo com Ancestrais do Continente Europeu , Análise Fatorial , Humanos , Estilo de Vida , Masculino , Transtornos Relacionados ao Uso de Opioides/classificação , Meio Social
8.
Pflugers Arch ; 354(1): 29-37, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1169756

RESUMO

Electrical and mechanical activity of circular muscle strips of guinea-pigs stomach, taken from the distal corpus/proximal antrum region, were recorded. Spontaneous activity consisting of phasic contractions combined with bursts of spike potentials was suppressed by verapamil (5-10-6 - 2-10-5 mol/l). Under these conditions acetylcholine produced a spike-free tonic activation. Under normal conditions phasic contractions were superimposed on this tonic activation. The acetylcholine-induced activation, therefore, consists of two different components, one of which can be selectively blocked with verapamil. Both components disappear quickly in calcium-free solution. It can be concluded that two different calcium activation systems are responsible for the two components of activation. In comparative studies with taenia coli preparations a comparable spike-free tonic activation was not found.


Assuntos
Acetilcolina/farmacologia , Potenciais de Ação , Contração Muscular , Músculo Liso/fisiologia , Estômago/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Cálcio/farmacologia , Colo/fisiologia , Feminino , Cobaias , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Verapamil/farmacologia
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