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1.
Ultrasound Obstet Gynecol ; 60(3): 309-327, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35229963

RESUMO

Endometriosis is a chronic systemic disease that can cause pain, infertility and reduced quality of life. Diagnosing endometriosis remains challenging, which yields diagnostic delays for patients. Research on diagnostic test accuracy in endometriosis can be difficult due to verification bias, as not all patients with endometriosis undergo definitive diagnostic testing. The purpose of this State-of-the-Art Review is to provide a comprehensive update on the strengths and limitations of the diagnostic modalities used in endometriosis and discuss the relevance of diagnostic test accuracy research pertaining to each. We performed a comprehensive literature review of the following methods: clinical assessment including history and physical examination, biomarkers, diagnostic imaging, surgical diagnosis and histopathology. Our review suggests that, although non-invasive diagnostic methods, such as clinical assessment, ultrasound and magnetic resonance imaging, do not yet qualify formally as replacement tests for surgery in diagnosing all subtypes of endometriosis, they are likely to be appropriate for advanced stages of endometriosis. We also demonstrate in our review that all methods have strengths and limitations, leading to our conclusion that there should not be a single gold-standard diagnostic method for endometriosis, but rather, multiple accepted diagnostic methods appropriate for different circumstances. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Endometriose , Testes Diagnósticos de Rotina , Endometriose/diagnóstico por imagem , Endometriose/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Gravidez , Qualidade de Vida , Ultrassonografia/métodos
2.
Reprod Domest Anim ; 49(4): 536-542, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24941906

RESUMO

The objective of this review is to evaluate the effectiveness of using pharmacological compounds on reproductive outcomes, particularly litter size, in North American swine. While the opportunity to improve reproduction in North American pigs exists, numerous hurdles need to be overcome in order to achieve measureable results. In the swine industry, the majority of piglet losses are incurred during pregnancy and around farrowing. Over the last 20 years, a reduction in losses has been achieved through genetic selection and nutritional management; however, these topics are the focus of other reviews. This review will evaluate attempts to improve litter size by reducing losses at various stages of the reproductive process, from the time of conception to the time of farrowing, using pharmacological compounds. Generally, these compounds are used to either alter physiological processes related to fertilization, embryonic attachment or uterine capacity, etc., or to facilitate management aspects of the breeding females such as inducing parturition. Although some of the pharmacological agents reviewed here show some positive effects on improving reproductive parameters, the inconsistent results and associated risks usually outweigh the benefits gained. Thus, at the present time, the use of pharmacological agents to enhance reproduction in North American swine may only be recommended for herds with low fertility and presents an avenue of research that could be further explored.


Assuntos
Resultado da Gravidez/veterinária , Reprodução/efeitos dos fármacos , Sus scrofa , Aborto Animal/prevenção & controle , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cruzamento/métodos , Dinoprosta/administração & dosagem , Estradiol/administração & dosagem , Feminino , Hormônio do Crescimento/administração & dosagem , Inseminação Artificial/veterinária , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , América do Norte , Placenta/anatomia & histologia , Gravidez , Progesterona/administração & dosagem , Seleção Genética , Sus scrofa/genética , Sus scrofa/fisiologia , Suínos , Doenças dos Suínos , Fator de Crescimento Transformador beta1/administração & dosagem , Útero/anatomia & histologia
3.
Reprod Domest Anim ; 47 Suppl 4: 394-401, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22827397

RESUMO

Prenatal mortality remains one of the major constraints for the commercial pig industry in North America. Twenty to thirty per cent of the conceptuses are lost early in gestation and an additional 10-15% is lost by mid-to-late gestation. Research over the last two decades has provided critical insights into how uterine capacity, placental efficiency, genetics, environment, nutrition and immune mechanisms impact successful conceptus growth; however, the exact cause and effect relationship in the context of foetal loss has yet to be determined. Similar to other mammalian species such as the human, mouse, rat, and primates, immune cell enrichment occurs at the porcine maternal-foetal interface during the window of conceptus attachment. However, unlike other species, immune cells are solely recruited by conceptus-derived signals. As pigs have epitheliochorial placentae where maternal and foetal tissue layers are separate, it provides an ideal model to study immune cell interactions with foetal trophoblasts. Our research is focused on the immune-angiogenesis axis during porcine pregnancy. It is well established that immune cells are recruited to the maternal-foetal interface, but their pregnancy specific functions and how the local milieu affects angiogenesis and inflammation at the site of foetal arrest remain unknown. Through a better understanding of how immune cells modulate crosstalk between the conceptus and the mother, it might be possible to therapeutically target immune cells and/or their products to reduce foetal loss. In this review, we provide evidence from the literature and from our own work into the immunological factors associated with porcine foetal loss.


Assuntos
Perda do Embrião/veterinária , Morte Fetal/veterinária , Prenhez , Suínos/fisiologia , Animais , Perda do Embrião/metabolismo , Feminino , Morte Fetal/metabolismo , Gravidez , Prenhez/metabolismo
4.
Hum Reprod Update ; 26(4): 545-564, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32378708

RESUMO

BACKGROUND: Neurotrophins of the nerve growth factor family are soluble polypeptides that are best known for their role in nerve growth, survival and differentiation in the central nervous system. A growing body of literature shows that neurotrophins and their receptors are also expressed throughout the reproductive tract. OBJECTIVE AND RATIONALE: Neurotrophins are key regulatory proteins in reproductive physiology during development and throughout adult life. Of the neurotrophins, the literature describing the expression and function of brain-derived neurotrophic factor (BDNF) and its high-affinity receptor, neurotrophin receptor kinase-2 (NTRK2), has been expanding rapidly. We therefore conducted a systematic inductive qualitative review of the literature to better define the role of the BDNF in the reproductive tract. We postulate that BDNF and NTRK2 are central regulatory proteins throughout the reproductive system. SEARCH METHODS: An electronic search of Medline (PubMed) and Web of Science for articles relating to BDNF and the reproductive system was carried out between January 2018 and February 2019. OUTCOMES: In the ovary, BDNF expression and levels have been linked with follicle organisation during ovarian development, follicle recruitment and growth and oocyte maturation. In the endometrium, BDNF is involved in cell proliferation and neurogenesis. In contrast, literature describing the role of BDNF in other reproductive tissues is sparse and BDNF-NTRK2 signalling in the male reproductive tract has been largely overlooked. Whilst estradiol appears to be the primary regulator of BDNF expression, we also identified reports describing binding sites for glucocorticoid and myocyte enhancer factor-2, a calcium-response element through activation of an N-methyl-D-aspartate (NMDA) receptor, and aryl hydrocarbon receptor nuclear transporter protein-4 (ARNT) response elements in promoter regions of the BDNF gene. Expression is also regulated by multiple microRNAs and post-translational processing of precursor proteins and intracellular shuttling. BDNF-NTRK2 signalling is modulated through tissue specific receptor expression of either the full-length or truncated NTRK2 receptor; however, the functional importance remains to be elucidated. Dysregulation of BDNF expression and circulating concentrations have been implicated in several reproductive disorders including premature ovarian failure, endometriosis, pre-eclampsia, intra-uterine growth restriction (IUGR) and several reproductive cancers. WIDER IMPLICATIONS: We conclude that BDNF and its receptors are key regulatory proteins central to gonadal development, ovarian regulation and uterine physiology, as well as embryo and placenta development. Furthermore, dysregulation of BDNF-NTRK2 in reproductive diseases suggests their potential role as candidate clinical markers of disease and potential therapeutic targets.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/fisiologia , Genitália/metabolismo , Animais , Endométrio/metabolismo , Feminino , Expressão Gênica , Humanos , Mamíferos/genética , Mamíferos/metabolismo , Oogênese/genética , Oogênese/fisiologia , Gravidez , Receptor trkB/genética , Receptor trkB/metabolismo , Transdução de Sinais/genética
5.
J Natl Cancer Inst ; 78(4): 701-5, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3470545

RESUMO

Inhibition of protein synthesis can alter cellular responsiveness to the classical anticancer drugs. The in vitro response of Chinese hamster ovary (CHO) cells to cisplatin with or without sparsomycin (Sm) was studied with the use of [3H]leucine and [methyl-3H]thymidine incorporation and clonogenic assay. Pretreatment of exponentially growing CHO cells with 1 microgram Sm/ml for 3 or 5 hours decreased [3H]leucine incorporation by 20% and resulted in significant resistance to cisplatin (P = .005). Sm in a concentration of 10 micrograms/ml reduced [3H]leucine and [methyl-3H]thymidine incorporation after 3 hours by 92 and 84%, respectively, and resulted in potentiation of the cisplatin cytotoxicity (P = .004). This effect was the same in the case of nonproliferating cells (P = .005), while protection due to Sm (1 microgram/ml) was seen only during cell proliferation. Simultaneous incubation and postincubation with Sm proved to have much less or no potentiating effect on cisplatin. The mechanisms of both protection and potentiation are still not clear, but our data indicate that Sm is a promising drug for further studies on the modulation of the cancer cell response to classical anticancer drugs.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Cisplatino/toxicidade , Biossíntese de Proteínas , Esparsomicina/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Sinergismo Farmacológico , Feminino , Ovário/citologia
6.
Reprod Toxicol ; 61: 105-13, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27037187

RESUMO

We previously demonstrated that Cigarette Smoke (CS) induces autophagy in the ovary. Therefore we aimed to determine if chloroquine (CQ) could inhibit CS-induced autophagy in the ovary. Eight week old mice were implanted with CQ pellets; 0, 25, and 50mg CQ/kg. Half of the animals in each group were exposed to room air and the other half were exposed to CS twice daily for 8 weeks. Ovaries were harvested for electron microscopy, gene and protein expression analysis. There was a significant increase in the production of autophagosomes in granulosa cells of mice exposed to CS (p=0.0297). However 25 and 50mg/kg CQ treatment significantly decreased the CS-induced autophagosomes (p=0.0505; p=0.0065) and attenuated the effects of CS on LC3B and BECN1 expression. In summary, this suggests that CQ attenuates CS-induced autophagy in the ovary and that ovarian protection from toxic insult is potentially feasible.


Assuntos
Hidroxicloroquina/farmacologia , Ovário/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Fumaça/efeitos adversos , Produtos do Tabaco/efeitos adversos , Animais , Autofagossomos/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Peso Corporal/efeitos dos fármacos , Feminino , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Ovário/metabolismo , Ovário/ultraestrutura , Transdução de Sinais/efeitos dos fármacos
7.
Exp Hematol ; 19(2): 110-4, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1991492

RESUMO

The relation between the proliferative state of normal human hematopoietic cells and their sensitivity to doxorubicin was studied. T-lymphocytes were stimulated with phytohaemagglutinin/interleukin 2 before or after a 2-h exposure to doxorubicin (range 0-2 microgram/ml). The doxorubicin concentration that inhibited DNA synthesis in 50% of the lymphocytes, measured qualitatively with 5-iodo-2'-deoxyuridine incorporation, was significantly lower (a factor of 2.5) in case of drug exposure of stimulated lymphocytes compared to nonstimulated lymphocytes. These proliferation-dependent differences were not related to differences in cellular drug concentrations, as was determined with flow cytometry. Bone marrow cells were stimulated for 2 days with human placenta-conditioned medium before or after exposure to doxorubicin (range 0-2 microgram/ml), after which they were cultured in a bone marrow clonogenic assay. In analogy with the lymphocyte experiments, proliferation-dependent differences in drug sensitivity were found. The drug concentration that inhibited the growth of granulocyte-macrophage colonies (granulocyte-macrophage colony-forming units, CFU-GM) to 50% appeared significantly lower (a factor of 3.4) with drug exposure of stimulated bone marrow cells compared to nonstimulated bone marrow cells. The relative insensitivity of quiescent, but potentially proliferative cells to doxorubicin might explain the recovery of hematopoiesis after doxorubicin-induced bone marrow hypoplasia.


Assuntos
Divisão Celular/efeitos dos fármacos , Doxorrubicina/toxicidade , Células-Tronco Hematopoéticas/citologia , Divisão Celular/fisiologia , Células Cultivadas , DNA/metabolismo , Relação Dose-Resposta a Droga , Granulócitos/efeitos dos fármacos , Granulócitos/fisiologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/fisiologia , Humanos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/fisiologia , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Linfócitos/fisiologia , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia
8.
Exp Hematol ; 8(1): 103-7, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7409031

RESUMO

Peripheral blood admixture in bone marrow aspirates of twenty patients with hematologic diseases were studied either with 51Cr labeled autologous erythrocytes or 125I-lab eled albumin. In these bone marrow aspirates 97.0 +/- 4.2% (mean +/- SD) of te hemoglobin content appeared to be derived from peripheral blood. Assuming the presence of a proportional number of peripheral nucleated cells one may calculate the fraction of peripheral nucleated cells in bone marrow aspirates (Fpb) from its hemoglobin levels. The Fpb in the twenty patients studied, varied from 6 to 93%, whereas in a group of 25 healthy volunteers the mean Fpb +/- SD was 14 +/- 8%. In order to obtain reliable results in quantitative bone marrow studies one has to take into account the fraction of peripheral nucleated cells in bone marrow aspirates.


Assuntos
Exame de Medula Óssea/métodos , Medula Óssea/patologia , Doenças Hematológicas/sangue , Adolescente , Adulto , Idoso , Contagem de Células Sanguíneas , Células da Medula Óssea , Núcleo Celular , Contagem de Eritrócitos , Doenças Hematológicas/patologia , Hematopoese , Hemoglobinas/análise , Humanos , Pessoa de Meia-Idade
9.
Exp Hematol ; 19(10): 1008-12, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1915701

RESUMO

Cell kinetics of two human leukemic cell lines, Molt-4 and K562, following a 2-h exposure to doxorubicin, were studied. DNA flow cytometry provided static information that for both cell lines a dose-dependent accumulation occurred at the G2 + M compartment that disappeared in time. Kinetic information was provided by time-monitoring cells labeled with 5-iodo-2-deoxyuridine (IdUrd) by two-parameter flow cytometry, analyzing the IdUrd label and the DNA content. The cell-cycle time (Tc) of exponentially growing Molt-4 cells was determined to be 20 h. Twenty-four hours after a 2-h exposure to 0.25 micrograms/ml doxorubicin, the Tc had increased to 23 h; following exposure to 1.0 micrograms/ml, it increased to 33 h. Cell kinetics of K562 cells following doxorubicin exposure were monitored in time up to 4 days. The average Tc of exponentially growing K562 cells was determined to be 24.7 h. Twenty-four hours following 2-h exposure to 0.25 or 0.5 micrograms/ml doxorubicin, the Tc were determined to be 28 and 32 h, respectively. After an additional 2 days, the Tc were both determined to be 24 h. The dose-dependent, reversible cell-cycle delay that persisted at least 48 h should be taken into account as an additional mode for decrease of a (tumor) cell population doubling time after exposure to doxorubicin.


Assuntos
Ciclo Celular/efeitos dos fármacos , DNA/análise , Doxorrubicina/farmacologia , Idoxuridina/metabolismo , Leucemia/patologia , Sobrevivência Celular/efeitos dos fármacos , Citometria de Fluxo , Humanos , Cinética , Células Tumorais Cultivadas
10.
J Immunol Methods ; 70(1): 23-30, 1984 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-6715893

RESUMO

Studies on splenic lymphocytes have hitherto been performed on single cell suspensions depleted of phagocytic cells by adherence to plastic or incubation with carbonyl iron. These techniques have the disadvantages of selective cell loss, suboptimal cell purification and cell activation. This paper describes purification of splenic lymphocytes by the use of counterflow centrifugation (CFC). The method was adapted to overcome pelleting of cells in the separation chamber to form a plug at the inlet and impede adequate flow. By combining 2 different separation chambers on line in 1 rotor this problem was overcome. Of all lymphocytes recovered after CFC 88.8 +/- 1.4% were collected in 2 pooled fractions with a purity of greater than or equal to 98% and a cell viability of 95%. After CFC, 80.8 +/- 12.1% of the viable cells loaded were recovered.


Assuntos
Separação Celular/métodos , Linfócitos , Baço/citologia , Plaquetas , Contagem de Células , Centrifugação/métodos , Eritrócitos , Granulócitos , Humanos , Macrófagos
11.
J Immunol Methods ; 25(3): 291-5, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-310854

RESUMO

A new method was employed to isolate lymphocytes from human peripheral blood. Continuous flow filtration through a nylon wool filter, at a flow rate of 1.4 ml/min, produced a lymphocyte yield of 90.5% and a purity of 96% without any shift in the B-T cell ratio. Ficoll-Isopaque with a specific gravity of 1.085 g/ml instead of 1.077 g/ml could be used to remove the erythrocytes. An overall recovery, including defibrination, filtration, Ficoll-Isopaque centrifugation and washing step, of 74.5% was achieved.


Assuntos
Linfócitos/imunologia , Linfócitos B , Separação Celular , Centrifugação com Gradiente de Concentração , Filtração , Humanos , Nylons , Linfócitos T , Fatores de Tempo
12.
J Immunol Methods ; 47(1): 31-8, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7310139

RESUMO

Continuous monitoring of cell light scatter during counterflow centrifugation of a mononuclear cell suspension allows counting and size recognition of the cell types elutriated. With this method an optimal separation point between monocytes and lymphocytes, determined for each individual donor, may be established. With a constant flow of 15 ml/min this separation point is found at centrifugal velocities ranging from 2348 to 2444 rpm (n = 10). From 50 ml venous blood, 84.1% +/- 4.1% (15.7 +/- 8.6 x 10(6)) of all elutriated monocytes, with a purity of 92.4% +/- 1.4%, is collected in a volume of 50 +/- 1 ml. In the same run, 92% +/- 4.3% of the lymphocytes is gathered in one fraction with a purity of 98.9% +/- 0.7%. After counterflow centrifugation, 91.6 +/- 10.5% of the cells loaded is recovered; viability exceeds 98%.


Assuntos
Citometria de Fluxo , Monócitos , Separação Celular , Sobrevivência Celular , Centrifugação , Humanos , Contagem de Leucócitos , Luz , Linfócitos , Espalhamento de Radiação
13.
J Med Chem ; 37(17): 2797-807, 1994 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-8064807

RESUMO

Porphycene photosensitizers bearing two or four methoxyethyl side chains were synthesized in nine steps from commercially available starting materials. Ether cleavage led to (hydroxyethyl)- and (bromoethyl)porphycenes that were converted to vinyl and benzo derivatives. Five of the side chain-functionalized porphycenes were biologically studied in comparison with two tetra-n-propylporphycenes. Porphycenes were incorporated in small unilamellar liposomes and incubated with cultivated SSK2 murine fibrosarcoma cells. Cellular uptake and phototoxicity 24 h after 5 J/cm2 laser light treatment were determined. The porphycenes tested were between 17 and 220 times more photodynamically active than the currently clinically used sensitizer Photofrin, although extinction coefficients of the porphycenes' irradiated bands are only approximately 10-fold higher. The LD50 concentration for SSK2 cells in the incubation medium was as low as (8.5 +/- 2.8) x 10(-9) M for tetrakis(methoxyethyl)porphycene. Two methoxy or hydroxy groups enhanced cellular uptake, three or four methoxy groups both enhanced and accelerated cellular uptake of tetraalkylporphycenes. Half-life times of the uptake processes varied between (0.14 +/- 0.04) and (14 +/- 4) h and cellular saturation levels between (1.2 +/- 0.2) and (26 +/- 3) pmol/10(5) cells. When individual uptake rates were accounted for, all porphycenes had a similar "cellular" phototoxicity, pointing toward a common mechanism of action. Evidence is presented for the assumption that cell membranes are the primary targets of the tested porphycenes and that membrane solubility may play a critical role in their photodynamic efficiency. The results show that nonionic polar side chain functionalities can strongly enhance cellular uptake and antitumor activity of lipophilic porphyrinoids and thus that the known lipophilicity/activity relationship can be reversed for very hydrophobic sensitizers.


Assuntos
Antineoplásicos/síntese química , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Porfirinas/síntese química , Animais , Antineoplásicos/química , Antineoplásicos/toxicidade , Transporte Biológico , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos , Desenho de Fármacos , Fibrossarcoma/metabolismo , Dose Letal Mediana , Luz , Lipossomos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Estrutura Molecular , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/toxicidade , Porfirinas/química , Porfirinas/toxicidade , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
Thromb Haemost ; 39(1): 12-21, 1978 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-580487

RESUMO

A rapid and simple turbidimetric determination of fibrinogen degradation products is described. This method is based on the increase of the turbidity due to the formation of precipitating antigen-antibody complexes after addition of rabbit antihuman fibrinogen antiserum to human serum. The increase in turbidity correlates very well with results obtained with the haemagglutination inhibition technique and has the advantage of a more objective quantitation. The reproducibility appears to be quite good. The turbidimetric method is independent of the colour of serum samples.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Nefelometria e Turbidimetria/métodos , Fotometria/métodos , Humanos
15.
Cancer Lett ; 36(1): 71-81, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3581058

RESUMO

In vitro proliferation of primary human head and neck squamous cell carcinomas was investigated using single cell suspensions and tissue explants of primary specimens and xenografts from 20 tumor specimens. The evaluations of the cells emerging in culture were performed with flow cytometry. Epithelial-like cells proliferated in serum-free medium, while no fibroblast-like cells were observed in culture. The epithelial-like cells could be subcultured several passages before senescence occurred. Conditioned medium or serum supplementation was necessary for a sustained outgrowth of malignant squamous cells as documented by flow cytometry. From a tumor line established in nude mice slowly proliferating tumor cells emerged. After 4-5 months in culture tumor cells seemed to be adapted to the culture conditions used. This resulted in a more consistent tumor cell proliferation. Early passage cultures from primary human head and neck squamous cell carcinomas are clearly difficult to obtain either from primary human specimens or from tumor lines established in nude mice.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Animais , Divisão Celular , Células Cultivadas , DNA/análise , Células Epiteliais , Feminino , Fibroblastos/citologia , Citometria de Fluxo , Humanos , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos BALB C
16.
Cancer Lett ; 32(1): 53-9, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3742487

RESUMO

The influence of protein synthesis inhibition by sparsomycin (Sm) on in vivo cisplatin activity has been studied on BALBc X DBA2: F1 mice bearing L1210 leukemia i.p. Sm alone at the dose range from 0.5 to 3.0 mg/kg did not significantly improve animal survival. Sm potentiated cisplatin activity only when given 3 or 6 h prior to cisplatin (P less than 0.001). Sm 0.5-1.5 mg/kg 3 h prior to cisplatin resulted in a significant prolongation of animal survival (P less than 0.001) and 66% cures in each group versus 0% due to cisplatin alone. Sm pretreatment decreased weight loss due to cisplatin suggesting that it probably is able to decrease cisplatin toxicity.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Esparsomicina/administração & dosagem , Animais , Sinergismo Farmacológico , Feminino , Leucemia L1210/tratamento farmacológico , Leucemia L1210/mortalidade , Camundongos , Camundongos Endogâmicos
17.
Leuk Res ; 6(2): 251-9, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6964370

RESUMO

Bone marrow cells of five patients with acute myeloid leukemia were fractionated by means of counterflow centrifugation (elutriation). The different fractions were enriched with cells belonging to subsequent stages of the cell cycle. Cytokinetic evaluation of these cell fractions was performed by [3H]thymidine autoradiography, [3H]thymidine incorporation and DNA/RNA-flow cytometry. Phosphorylation of cytosine arabinoside (ara-C, 1-beta-D-arabinofuranosylcytosine) in the different fractions was measured by incubation of the cells for 30 min with 1.07 microM [3H]ara-C. Phosphorylation of ara-C in the whole bone marrow samples ranged from 5.9 to 33.2 pmol/10(6) cells. In the fractions containing only G1-phase cells, phosphorylation ranged from 1.2 to 19.5 pmol/10(6) cells. The phosphorylation seems to increase before DNA synthesis starts. Maximal activities were found in the fractions enriched with cells in late G1- or S-phase of the cell cycle. In these fractions the ara-C phosphorylating activity was 1.5-8 times higher compared to the fractions with the lowest activity. One may therefore assume that not only S-phase cells are killed by ara-C, but that G1-phase cells which can phosphorylate ara-C, may also be doomed when they enter S-phase, since the elimination of the intracellular cytosine arabinoside tri-phosphate (ara-CTP) is a relatively slow process. The fraction of G1-phase cells phosphorylating ara-C, may be an important determinant in the extent of the cell-killing effect of ara-C treatment in the different leukemias.


Assuntos
Ciclo Celular , Citarabina/metabolismo , Leucemia Mieloide Aguda/metabolismo , Separação Celular , Replicação do DNA , Humanos , Leucemia Mieloide Aguda/patologia , Fosforilação
18.
Cancer Chemother Pharmacol ; 20(2): 115-24, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3664930

RESUMO

Sparsomycin is a cytotoxic drug exhibiting a broad spectrum of in vitro activity against murine tumors and many tumor cell lines. It also appears to be a potent stimulator of the antitumor activity of cisplatin against L1210 leukemia in vivo. However, because of its toxicity, the antitumor activity of sparsomycin on murine tumors in vivo has been disappointing. The purpose of our study was to investigate the pharmacokinetics of this drug as well as the possible mechanisms that produce sparsomycin toxicity. Tests on beagle dogs revealed that about 60% of the drug is eliminated by metabolic clearance, while 40% is eliminated by the kidneys. After a single bolus injection of 0.1 mg/kg sparsomycin without narcosis, sparsomycin was eliminated with a t beta 1/2 of 0.6-0.7 h, the AUC being 0.32-0.38 mg.h.l-1, and the volume of distribution (Vd) 0.26 l/kg. In addition to being subject to glomerular filtration, sparsomycin is probably also actively excreted and actively reabsorbed by the renal tubuli. Sparsomycin itself may inhibit its active tubular excretion, thus resulting in a decrease in the drug's renal clearance and its accumulation in the plasma. Sparsomycin appeared to be toxic primarily in the liver, disturbing its function and the synthesis of plasma proteins. Two out of five dogs developed hemorrhagic diathesis due to hypofibrinogenemia and deficiency of other blood-coagulation factors. Sparsomycin was not toxic to the bone marrow.


Assuntos
Antibióticos Antineoplásicos/farmacocinética , Esparsomicina/farmacocinética , Animais , Proteínas Sanguíneas/análise , Cães , Olho/efeitos dos fármacos , Fator VII/análise , Fibrinogênio/análise , Infusões Intravenosas , Injeções Intravenosas , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Esparsomicina/administração & dosagem , Esparsomicina/toxicidade
19.
Photochem Photobiol ; 61(4): 350-2, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7740077

RESUMO

The current trend in methodology for determining IR and near-IR absorption spectra is to employ interferometer-based instruments to replace the monochromator-based devices used heretofore. As a dispersion element, the interferometer offers major improvements in spectral resolution (Connes advantage), light throughput (Jacquinot advantage) and data acquisition through multiplexing (Felgett advantage). We have compared signal-to-noise (S/N) ratios of grating-based and interferometer-based instruments for making spectral determinations of near-IR luminescence. Our results show that under identical excitation and detector conditions the interferometer instrument easily outperforms the grating, giving a 10-fold improvement in S/N at high signal amplitude (A488nm = 0.97) and a 20-fold improvement when the signal amplitude is low (A488nm = 0.06). Although some spectral resolution is sacrificed when scan times on the Fourier transform (FT)IR are significantly shortened, the S/N ratio was found only to decrease by a factor of 2 for a 10-fold decrease in scan time. This adds to the advantages of the FTIR technique because the S/N will thus improve for the same total acquisition time.


Assuntos
Interferometria/métodos , Oxigênio/química , Espectrofotometria Infravermelho/métodos , Estudos de Avaliação como Assunto , Luminescência , Fotoquímica , Oxigênio Singlete
20.
Photochem Photobiol ; 65(1): 96-102, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9066289

RESUMO

Tris (2,2'-bipyridyl)ruthenium(II)chloride hexahydrate (Ru[bpy]3(2+)) free in solution and adsorbed onto antimony-doped SnO2 colloidal particles was used as a photosensitizer for a comparison of the O2(1 delta g) and electron-transfer-mediated photooxidation of tryptophan (TRP), respectively. Quenching of excited Ru(bpy)3(2+) by O2(3 sigma g-) in an aerated aqueous solution leads only to the formation of O2(1 delta g) (phi delta = 0.18) and this compound was used as a type II photosensitizer. Excitation of Ru(bpy)3(2+) adsorbed onto Sb/SnO2 results in a fast injection of an electron into the conduction band of the semiconductor and accordingly to the formation of Ru(bpy)3(2+) and was used for the sensitization of the electron-transfer-mediated photooxidation. The Ru(bpy)3(3+) is reduced by TRP with a bimolecular rate constant kQ = 5.9 x 10(8) M-1 s-1, while O2(1 delta g) is quenched by TRP with kt = 7.1 x 10(7) M-1 s-1 (chemical + physical quenching). Relative rate constants for the photooxidation of TRP (kc) via both pathways were determined using fluorescence emission spectroscopy. With Np, the rate of photons absorbed, being constant for both pathways we obtained kc = (372/Np) M-1 s-1 for the O2(1 delta g) pathway and kc > or = (25,013/Np) M-1 s-1 for the electron-transfer pathway, respectively. Thus the photooxidation of Trp is more than two orders of magnitude more efficient when it is initiated by electron transfer than when initiated by O2(1 delta g).


Assuntos
Triptofano/química , 2,2'-Dipiridil/análogos & derivados , Transporte de Elétrons , Corantes Fluorescentes , Cinética , Cinurenina/análogos & derivados , Compostos Organometálicos , Fotoquímica , Fotólise
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