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1.
Heliyon ; 10(12): e32626, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38994085

RESUMO

It is well-known that the survival of metastatic cells during their dissemination plays an important role in metastasis. However, does this mean that the final result of the metastatic cascade (the volume of metastatic damage to distant organs and tissues) depends on, or at least correlates with, the degree of resistance to anoikis (distinctive hallmarks of metastatic cells)? This question remains open.The aim of the work was to study in vitro the changes in the survival rates, proliferative activity, oxidative stress, and glycolysis intensity during three days of anchorage-dependent and anchorage-independent growth of two Lewis lung carcinoma cell lines (LLC and LLC/R9) and compare these changes with the status of mitochondria and metastatic potential of the cells in vivo. Methods: The number and volume of lung metastases were estimated for each cell line after intramuscular inoculation of the cells in C57Bl/6 mice. For the in vitro study, the cells were seeded on Petri dishes pretreated with poly-HEMA or untreated dishes and then allowed to grow for 3 days. Cell viability, cell cycle progression, the level of reactive oxygen species (ROS), glucose consumption and lactate production rates were investigated daily in both growth conditions. An electron microscopy study of intracellular structures was carried out. Results: The study showed (as far as we know for the first time) a correlation between the metastatic potential of cells (determined in vivo) and their sensitivity to anoikis (assessed in vitro). The transition of LLC/R9 cells with an inherently defective mitochondrial system to the conditions of anchorage-independent growth was characterized by a decrease in survival, a slowdown in growth rates, an increase in both glucose consumption rate and intracellular ROS levels and manyfold lower metastatic potential, compared to highly metastatic LLC cells with the normal mitochondrial system.

2.
Georgian Med News ; (335): 84-89, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37042595

RESUMO

The conceptual model of rehabilitation and suicidal behaviour prevention in dementia, considering the multiple components, is presented in the article. The developed program of the complex differentiated medical and psychological rehabilitation and suicidal behaviour prevention (MPRS BP) in patients with dementia is aimed at the preventive measures of the suicidal behaviour (SB) through the depressive symptoms reduction, patient's mind and cognitive status stabilization, self-aggression decreases, social functioning and independence increase in patients with dementia. The individual approach to the prevention of SB in patients with dementia considered the SB factors (extra- and intrapersonal), SB formation mechanisms (cognitive, depressive, and psychological), clinical psychopathological SB correlators (especially gender-based) in different types of dementia. Offered MPRS BP program is based on the complex approach to rehabilitation. It combines pharmacotherapy, psychotherapy (crisis therapy, rational psychotherapy, art therapy, family psychotherapy), psychoeducation, psychological training (cognitive, communicative and social skills training) keeping to the principles of systematicity, complexity, integrity, phasing, personal interventions, provision of assistance in time. According to the approbation results of the MPRS BP program in dementia, its high efficiency was demonstrated compared to the traditional treatment programs of this category of patients.


Assuntos
Demência , Ideação Suicida , Humanos , Psicoterapia/métodos , Demência/diagnóstico
3.
Exp Oncol ; 41(2): 123-129, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31262158

RESUMO

It is known that the arsenal of chemotherapeutic agents for the treatment of malignant brain tumors is quite limited, which causes the high relevance of research aimed at finding new effective antitumor regimens, including the use of energy metabolism modifiers. AIM: To investigate the anti-glioma activity of sodium dichloroacetate (DCA) and metformin (MTF) used in combination in vitro and in vivo. MATERIALS AND METHODS: Cell survival, cell cycle, apoptosis, mitochondrial membrane potential (Δψm), ATP level, the glucose consumption rate, and lactate production rate were determined in vitro in cultured glioma C6 cells. The antitumor action of agents in vivo was evaluated routinely by the prolongation of the life span of rats with transplanted intracerebral glioma C6 and was confirmed by histological examination of tumor tissue. RESULTS: The half maximal inhibitory concentration (IC50) for DCA and MTF used separately was 79.2 ± 2.1 mM and 78.4 ± 4.0 mM, respectively, whereas IC50 for DCA used in combination with 7.8 mM MTF was 3.3 fold lower (24.0 ± 1.2 mM, p < 0.05). The 1-day incubation of cells with DCA at a concentration close to IC50 (25 mM), in combination with MTF at a concentration by order lower than IC50 (7.8 mM), in contrast to their separate use, resulted in a decrease in the number of viable cells by 40% (p < 0.05); redistribution of the cells by the cell cycle phases toward decreased proportion of cells in the S-phase by 46% (p < 0.05) and an increased percentage of cells in the G0/G1 phase by 24% (p < 0.05) compared to similar indices in the control. High proapoptotic activity of DCA in combination with MTF was supported by a significantly higher percentage of apoptotic cells in vitro than in the control (18.9 ± 4.4% vs 5.7 ± 1.3%, p < 0.05) and a high number of tumor cells with signs of apoptosis revealed during the histological examination of tumor pathomorphosis. The combined effect of DCA and MTF resulted in almost 4-fold decrease of the glucose consumption rate by glioma C6 cells (0.23 ± 0.05 µmol/106 cells/h vs 0.91 ± 0.12 µmol/106 cells/h, p < 0.05) compared to the corresponding parameters in the control, and 2-fold increased rate of lactate production (1.06 ± 0.03 µmol/106 cells/h vs 0.53 ± 0.03 µmol/106 cells/h, p < 0.05). At the same time, both Δψm and the level of intracellular ATP in the glioma C6 cells treated with DCA and MTF, both separately and in combination, did not differ significantly from those indices in the control. In in vivo studies, the average life span of rats with intracranial transplanted glioma C6, treated with DCA in combination with MTF in a total dose of 1.1 and 2.6 g/kg body weight, respectively, was 50% higher (p < 0.001) than in the control group. In contrast, in the case of single-use (at a dose of 2.6 g/kg), MTF increased the life span of tumor-bearing animals just by 19% (p < 0.01), whereas DCA alone (at a dose of 1.1 g/kg) did not significantly change the survival time of rats. CONCLUSIONS: The obtained data indicate synergism of anti-glioma action of DCA and MTF in a case of their combined use both in vitro and in vivo and may be considered a starting point for the development of effective treatment regimens for malignant brain tumors based on the combined use of DCA and MTF.


Assuntos
Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Ácido Dicloroacético/farmacologia , Glioma/tratamento farmacológico , Metformina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Glioma/patologia , Glucose/metabolismo , Lactatos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ratos
4.
Georgian Med News ; (287): 13-19, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30958281

RESUMO

Anesthesia of curettage of uterine cavity (CUC) at postoperative period causes additional expenses. Preventive intraoperative anesthesia makes it possible to reduce these expenses and provide significant positive economic effect on state budget. The objective of this research is determination of influence of different methods of anesthesia of CUC on cash value of anesthetic maintenance of CUC and the possibility of saving of budgetary funds. 128 women took part in the research. They underwent the procedure of CUC. Anesthetic maintenance was performed using different medicamental combinations and their dosages. Mathematical calculation of the cost of each CUC stage was done considering the cost of consumables, medical preparations and value of labor of medical staff. In the course of this research, it was proven that a combination of additional use of dexketoprofen (at the stage of premedication of CUC) and performing preventive intraoperative applicational anesthesia with bupivacaine solution can save 130 452,26UAH of wage fund per year and general budget savings within the confines of a state can each 9 954 617,67UAH per year.


Assuntos
Serviço Hospitalar de Anestesia/economia , Anestesia/economia , Bupivacaína/economia , Curetagem/métodos , Útero/cirurgia , Serviço Hospitalar de Anestesia/organização & administração , Bupivacaína/administração & dosagem , Redução de Custos , Curetagem/economia , Feminino , Humanos , Período Pós-Operatório
5.
Nanoscale ; 9(19): 6436-6447, 2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28463371

RESUMO

The limited performance of platinum-based electrocatalysts for glucose electrooxidation is a major concern for glucose fuel cells, since glucose electrooxidation is characterized by slow reaction kinetics and low diffusion coefficient. Here, the presented graphene-supported platinum-based hierarchical nanostructures attain highly enhanced electrocatalytic activity towards glucose oxidation. Platinum nanoparticles electrodeposited on graphene support retain mechanical stability and act as junctions allowing a reliable, smooth and dense growth of platinum nanowires with extremely small diameters (>10 nm) on graphene. The electrode's surface roughness was increased by factors up to 4000 to the geometrical surface area enabling maximized exploitation of the electrocatalytic activity of platinum and efficient electron transfer between nanowires and the substrate. The unique three-dimensional geometry of these hierarchical nanostructures has a significant impact on their catalytic performance offering short diffusional paths for slow glucose species, thus, mass transport limitations are optimized leading to lower polarization losses. This was examined by galvanostatic measurements of the operation as anodes in glucose half-cells under conditions corresponding to implantable glucose fuel cells. The presented hierarchical nanostructures show remarkably enhanced catalytic performance for glucose electrooxidation, i.e. a negatively shifted open circuit potential of -580 mV vs. Ag/AgCl, hence, representing appropriate electrocatalysts for use as anodes in glucose fuel cells. In combination with a non-metal N-doped graphene cathode, a cell potential of 0.65 V was achieved at a galvanostatic load of 17.5 µA cm-2 which noticeably surpasses the performance of state of the art catalysts for the aforementioned operation conditions.

6.
Mater Sci Eng C Mater Biol Appl ; 69: 122-7, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27612696

RESUMO

This work describes the development of a new biosensor for methylparaben determination using electrocatalytic properties of hemoglobin in the presence of hydrogen peroxide. The voltammetric oxidation of methylparaben by the proposed biosensor in phosphate buffer (pH=7.0), a physiological pH, was studied and it was confirmed that methylparaben undergoes a one electron-one proton reaction in a diffusion-controlled process. The biosensor was fabricated by carbon paste electrode modified with hemoglobin and multiwalled carbon nanotube. Based on the excellent electrochemical properties of the modified electrode, a sensitive voltammetric method was used for determination of methylparaben within a linear range from 0.1 to 13µmolL(-1) and detection limit of 25nmolL(-1). The developed biosensor possessed accurate and rapid response to methylparaben and showed good sensitivity, stability, and repeatability. Finally, the applicability of the proposed biosensor was verified by methylparaben evaluation in various real samples.


Assuntos
Técnicas Biossensoriais/métodos , Hemoglobinas/química , Parabenos/análise , Técnicas Biossensoriais/economia , Técnicas Eletroquímicas , Eletrodos , Humanos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Varredura , Nanotubos de Carbono/química , Oxirredução , Propriedades de Superfície
8.
Exp Oncol ; 35(1): 15-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23528310

RESUMO

AIM: To study cytotoxicity of cisplatin conjugated with magnetic fluid (nanocomposite) upon exposure to magnetic field on sensitive and resistant to cisplatin MCF-7 human breast cancer cells. METHODS: Cytotoxic activity was evaluated by MTT-test, intracellular iron accumulation was analyzed cytochemically, genotoxicity was studied by micronucleus test and DNA comet assay, ultrastructure was studied by electron microscopy techniques. RESULTS: Nanocomposite of cisplatin was more toxic to MCF-7/S and MCF-7/CP cells compared to cisplatin in conventional pharmaceutical form. In nanocomposite-treated cells we observed more expressed signs of dystrophy (especially following application of magnetic field) and drastic alterations of nuclei ultrastructure with significant accumulation of iron nanoparticle clusters. The potent toxic action of nanocomposite is confirmed by electron microscopy and by marked genotoxicity, especially against MCF-7/CP cells. CONCLUSION: The enhancement of cyto- and genotoxicity of cisplatin nanocomposite combined with magnetic field in comparison with effect of convetntional cisplatin alone was demonstrated.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Cisplatino/farmacologia , Campos Magnéticos , Nanopartículas de Magnetita , Nanocompostos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Cisplatino/metabolismo , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Feminino , Humanos , Células MCF-7
9.
Exp Oncol ; 35(1): 45-52, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23528316

RESUMO

UNLABELLED: A perspective adsorptive method to minimize systemic toxic effects of chemotherapy is enterosorption (ES). However, the capabilities of this method are far from being completely studied. The question remains opened - should ES be initiated in the first hours on completing cytostatic infusion without the risk of their anticancer activity to be decreased. AIM: to analyze ES influence on anticancer activity and toxic reactions of cisplatin (CP) upon the use of carbon enterosorbent in 1 h after intravenous administration of cytostatic. METHODS: CP at the dose of 1 mg/kg body weigh (BW) was administered to Guerin carcinoma-bearing rats each second day for two weeks. Enterosorbents on the basis of highly activated carbon fibers were administered by per os daily 1 h after CP injection. 3 days after the last CP administration the rats were weighted and blood under ether narcosis has been taken for biochemical examination. Tumors and innate organs were isolated, weighted, and fixed in 4% buffered formalin for morphologic examination. RESULTS: In rats administered with CP at the background of ES, BW loss was in 1.6 times lower than in animals after CP session. Relative kidney weight in CP-treated rats was 33.9% higher than in normal ones (p ≤ 0.05). No significant differences were detected between relative kidney weights in the CP + ES-treated and intact animals. Introduction of ES allowed prevent an 30% increase of creatinin content observed in blood plasma after CP treatment (р ≤ 0.05). Urea content was 1.7 times lower in blood plasma of CP + ES-treated rats than after CP treatment. CP caused significant toxic injuries in kidneys, liver, and spleen tissues. Morphologic structure of organs in rats treated with CP at the background of ES was affected at much lower degree. In tumors, large areas of newly formed connective tissue and blood vessels have been fixed after the CP+ES action instead of large necrotic area observed after CP treatment. ES caused insignificant suppression of Guerin carcinoma growth and had additional impact to inhibitory action of CP. CONCLUSION: Active carbon enterosorbents which are administrated just 1 h after CP administration possesses detoxicating potential sufficient for significant elimination of toxic effect of the cytostatic at the background of complete preservation of its antitumor activity.


Assuntos
Antineoplásicos/efeitos adversos , Carbono/administração & dosagem , Cisplatino/efeitos adversos , Enteroadsorção , Neoplasias/tratamento farmacológico , Animais , Peso Corporal/efeitos dos fármacos , Carbono/química , Creatinina/sangue , Rim/efeitos dos fármacos , Ratos , Ácido Úrico/sangue
10.
Phys Chem Chem Phys ; 14(1): 273-9, 2012 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-22073402

RESUMO

Ultrafast transient absorption spectroscopy is performed on a novel donor-acceptor-donor triad made of two identical bisthiophene derivatives as electron donors and a central perylenediimide moiety as electron acceptor. The triad is extended at both ends by covalently bound siloxane chains that confer self-organisation into thin smectic films at ambient temperature. When diluted in chloroform, selective excitation of the donor moiety leads to resonance energy transfer within 130 fs to the acceptor moiety, followed by the formation of a charge transfer (CT) state in ~3 ps. The CT state recombines entirely on a 55 ps time scale. In the liquid crystal films, excitonic intermolecular coupling leads to significant changes in the dynamics. Most remarkably, ultrafast intra- and intermolecular CT state formation occurs in about 60 fs, i.e. on a time scale comparable to electronic coherence times. While the intra-molecular CT states recombine on the same time scale as in solution or even faster, inter-molecular CT states live for about 1 ns. Last, triplet states of the perylenediimide moiety dominate the differential absorption after ~1 ns. We anticipate that the fast recombination of intra-molecular CT states and the triplet state formation may severely limit the photo-current in these materials.

11.
Exp Oncol ; 33(2): 78-82, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21716203

RESUMO

AIM: To study distribution and accumulation of liposomal form of doxorubicin in human breast cancer cells of MCF-7 line and Dox-resistant subline MCF-7/Dox. METHODS: High performance liquid chromatography and laser confocal microscopy were used. RESULTS: It has been shown that conventional form of doxorubicin was more efficiently delivered to the MCF-7 cells already after 30 min of incubation amounting to its maximum concentration after 4 h. MCF-7/Dox cells are characterized by lower doxorubicin accumulation rate compared with parental cells. The quantity of accumulated liposomal form of doxorubicin is high in MCF-7 cells, and, what is important, Dox-resistant cells accumulated higher levels of liposomal form of doxorubicin than its conventional form. CONCLUSION: It has been shown that intracellular distribution and accumulation of liposomal forms of doxorubicin in parental and Dox-resistant MCF-7 cells differs from that of conventional doxorubicin.


Assuntos
Neoplasias da Mama/metabolismo , Doxorrubicina/metabolismo , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Lipossomos , Microscopia Confocal
12.
Exp Oncol ; 32(1): 23-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20332761

RESUMO

AIM: To determine the main ultrastructural changes in MCF-7 sublines sensitive and resistant to cytotoxic action of anticancer drugs, resulting from the treatment with conventional and liposomal forms of cisplatin and doxorubicin. METHODS: Electron microscopy, light microscopy, MTT-test. RESULTS: It has been shown that the phenomenon of drug resistance is associated with complication of ultrastructural organization of cells and more high differentiation by the main cytomorphologic characteristics which promote their resistance to cytotoxic action of anticancer preparations. Cytoarchitectonics of all resistant cells possesses common patterns and doesn't depend on the particular drugs toward which the resistance has been developed. It has been shown that the cells of the parental form MCF-7 line are more sensitive to cytotoxic action of doxorubicin than to cisplatin. Liposomal forms of anticancer drugs used at the same concentrations that the conventional ones, especially that of doxorubicin, caused more expressed alterations in ultrastructural organization of cells of all studied sublines with dominance of apoptotic processes. CONCLUSION: Evaluating an effect of equal concentrations of cisplatin and doxorubicin in conventional and liposomal forms, one may conclude on higher cytotoxic action of doxorubicin vs. cisplatin that is expressed in a wider spectrum of ultrastructural changes of cell architectonics in different sublines of MCF-7 cells and higher rate of apoptosis.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Neoplasias/ultraestrutura , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/ultraestrutura , Biomarcadores Tumorais , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/fisiologia , Feminino , Humanos , Lipossomos , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Neoplasias/patologia , Polirribossomos/efeitos dos fármacos , Polirribossomos/metabolismo
13.
Exp Oncol ; 32(4): 237-42, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21270752

RESUMO

AIM: To study the ultrastructure and some functional indexes of tumor cells treated with stabilized iron nanoparticles in vitro. METHODS: 3-[4,5dimethylthiazol-2-1]-2,5-diphenyltetrazolium bromide (MTT)-test, electron microscopy, polarography with applying of closed Clark's electrode. RESULTS: It was shown that cultivation of cells with stabilized Fe(3)O(4) leads to intracellular accumulation of ferromagnetic nanoparticles. The most active ferromagnetic uptake by cells has been observed after 24 and 48 h of incubation. The presence of ferromagnetic in cells led to altered mitochondrial structure that caused the decrease of oxygen uptake rate in the cells of all studied lines. Ferromagnetic released from the majority of cells via exocytosis or clasmacytosis after a certain period of time. The number of dead cells or cells with severe damage was moderate, so cytotoxic action of stabilized iron oxide nanoparticles was minimal toward the studied cell lines. CONCLUSION: the presence of ferromagnetic nanoparticles in culture medium led to alterations in mitochondria ultrastructural organization and decrease of oxygen uptake by mitochondria in sensitive and anticancer-drugs resistant cells.


Assuntos
Compostos Férricos/toxicidade , Nanopartículas Metálicas/toxicidade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Linhagem Celular Tumoral , Compostos Férricos/administração & dosagem , Humanos , Microscopia Eletrônica de Transmissão
14.
Exp Oncol ; 28(3): 225-30, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17080017

RESUMO

AIM: To study the PKD2 expression, autophosphorylation and localization in reactive lymph nodes and tumors of lymphoid tissues. MATERIALS AND METHODS: Specific antibodies, which recognize PKD1/2 or PKD2 and autophosphorylated PKD1/2, were used for immunohistochemical and biochemical studies of tonsils, reactive lymph nodes, tumor samples of non-Hodgkin's lymphoma (NHL) and Hodgkin's lymphoma (HL). RESULTS: Immunohistochemical and biochemical analysis of PKD1 and PKD2 expression showed PKD2 expression in tonsils, reactive lymph nodes and tumor tissues from patients with NHL and HL. Furthermore, we were not able to reveal PKD1 expression in studied lymphoid tissues. In tonsils and reactive lymph nodes the PKD2 expression was detected in T and B cell zones with highest level in germinal centers of lymphoid follicles and the maximum level of autophosphorylation in the light zones of the germinal centers. We found that low level of PKD2 expression and autophosphorylation was characteristic feature for mantle cell lymphomas, Burkitt's lymphomas, and in 50% of CLL/small lymphocytic lymphomas. Lymphoma cells of germinal center origin and with activated B cell phenotype (diffuse large B cell lymphomas, HL) and anaplastic large cells lymphoma demonstrated the high level of PKD2 expression and autophosphorylation. CONCLUSIONS: The level of PKD2 expression and autophosphorylation in neoplastic cells corresponds to the expression pattern of this kinase in their normal analogs, and to the level of cell differentiation and activation.


Assuntos
Doença de Hodgkin/enzimologia , Linfoma não Hodgkin/enzimologia , Proteínas Quinases/análise , Doença de Hodgkin/patologia , Humanos , Imuno-Histoquímica , Linfonodos/enzimologia , Linfoma não Hodgkin/patologia , Tonsila Palatina/enzimologia , Fosforilação , Proteína Quinase C/análise , Proteína Quinase D2
17.
Cell Tissue Res ; 318(2): 419-28, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15322911

RESUMO

The ultrastructural mechanisms of waste-sperm phagocytosis and postspawning shrinkage were studied for accessory cells (nutritive phagocytes; NPs) of the sea urchin Anthocidaris crassispina. Sperm cells were phagocytosed by NPs; they penetrated into the cytoplasm of the NPs inside heterophagosomes formed by an invagination of the cell membrane. Single-sperm-containing heterophagosomes aggregated to form large multisperm heterophagosomes that were accompanied by cytoplasmic vesicles and lipids. Two types of vesicle, viz., Golgi-complex-derived electron-dense vesicles ("zymogen granules") and smooth-endoplasmic-reticulum-derived electron-lucent vesicles, were incorporated within multisperm heterophagosomes. Completed multisperm heterophagosomes were transformed into electron-dense remnant bodies, the content of which underwent destruction, resulting in "empty" vacuoles inside the remnant body. The "empty" vacuoles were then compressed by the surrounding cytoplasm. Shrinkage of NPs occurred upon completion of sperm degeneration in gonad tubules. This process was undertaken by structures termed cell-size-reducing autolysosomes, which performed two types of autolysis, and resulted in the formation of "cheese-hole"-like vacuoles in the cytoplasm of NPs. Subsequent cytoplasmic compression of these vacuoles was required for the reduction in size of NPs, an essential event for remodeling the cell for the next gametogenetic cycle.


Assuntos
Anthocidaris/fisiologia , Vesículas Citoplasmáticas/fisiologia , Fagócitos/fisiologia , Fagocitose/fisiologia , Espermatozoides/fisiologia , Animais , Anthocidaris/citologia , Vesículas Citoplasmáticas/ultraestrutura , Homeostase , Masculino , Microscopia Eletrônica de Transmissão , Fagócitos/ultraestrutura , Estações do Ano , Espermatozoides/ultraestrutura
18.
Neoplasma ; 39(1): 3-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1528302

RESUMO

Monoclonal antibodies (mAbs) of IPO series were developed following immunization with human B cell lines RPMI-1788, Daudi, and spleen cells from a patient with hairy cell leukemia. Reactivity of these mAbs was studied on 19 human cell lines, mononuclear cells of 50 healthy persons and 142 patients with leukemias and lymphomas. It was shown that mAbs IPO-3, IPO-10 and IPO-24 define B cell-specific antigens expressed at different stages of maturation. MAb IPO-3 reacted with activated B lymphocytes. MAb IPO-10 defined the antigen which appears on B cell progenitors following HLA-DR and proceeding CD19, CD10, CD22, CD37; cy mu and CD20 and have been lost during terminal differentiation. The antigen detected by mAb IPO-24 was expressed throughout B cell ontogeny from pre-B cell until the B-blasts. MAb IPO-4 detected an antigen of activated T and B lymphocytes. These mAbs are useful tools in the leukemia and lymphoma phenotypic characterization and classification.


Assuntos
Anticorpos Monoclonais , Antígenos de Diferenciação de Linfócitos B/análise , Antígenos de Neoplasias/análise , Leucemia/imunologia , Linfócitos/imunologia , Animais , Antígenos de Diferenciação de Linfócitos B/imunologia , Antígenos de Superfície/análise , Diferenciação Celular/fisiologia , Humanos , Imunofenotipagem , Leucemia/patologia , Lipopolissacarídeos , Linfonodos/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Linfócitos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Tonsila Palatina/imunologia , Mitógenos de Phytolacca americana , Células Tumorais Cultivadas
19.
Cell Mol Neurobiol ; 7(4): 381-90, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2837328

RESUMO

1. The effect of serotonin on the acetylcholine (ACh) response has been studied by means of voltage clamp and intracellular perfusion in unidentified isolated neurons from parietal and visceral ganglia of Lymnaea stagnalis. 2. In most cells studied serotonin added to the internal or external solution decreases the response to ACh. 3. In other neurons serotonin added to the intracellular solution increases the response to ACh; when it is added extracellularly it produces the opposite effect on the same cells. 4. The decreasing effect of serotonin on ACh currents is mimicked by cyproheptadine, an antagonist of serotonin receptors, and by the intracellular application of cyclic AMP (cAMP) forskolin. 5. The enhancing effect of intracellularly applied serotonin on ACh currents is blocked by cyproheptadine and is not obtained by the intracellular administration of cAMP and forskolin. In some cells the enhancing effect of serotonin appears after forskolin. 6. The results suggest a modulating effect of serotonin on cholinergic synaptic transmission in the nervous system of mollusks. The possible existence of intracellular serotonin receptors is discussed.


Assuntos
Acetilcolina/farmacologia , Gânglios/fisiologia , Serotonina/farmacologia , Animais , Colforsina/farmacologia , AMP Cíclico/farmacologia , Ciproeptadina/farmacologia , Gânglios/efeitos dos fármacos , Técnicas In Vitro , Potenciais da Membrana/efeitos dos fármacos
20.
Artigo em Inglês | MEDLINE | ID: mdl-2888583

RESUMO

1. At different levels of the holding potential on neuron R2 membrane in the Aplysia depilans abdominal ganglion, dopamine injected intracellularly increases the amplitude of both inward and outward currents recorded in response to the application of acetylcholine (ACh) to the ganglion surface. 2. The addition of dopamine to the external perfused solution produces generation of inward currents and a decrease in the cell response to the ACh. 3. The enhancing effect of injected dopamine on ACh responses is retained after inhibition of acetylcholinesterase (AChE) by a specific organophosphorous inhibitor, compound Gd-42. 4. The modulating effect of injected dopamine on ACh responses is discussed in terms of the existence of intracellular receptors of neurotransmitters in the differentiated cells.


Assuntos
Acetilcolina/metabolismo , Dopamina/farmacologia , Gânglios/citologia , Neurônios/metabolismo , Acetilcolinesterase/metabolismo , Animais , Aplysia , Inibidores da Colinesterase/farmacologia , Dopamina/administração & dosagem , Gânglios/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Microinjeções , Neurônios/efeitos dos fármacos , Compostos Organotiofosforados/farmacologia
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