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1.
Akush Ginekol (Sofiia) ; 54(2): 14-8, 2015.
Artigo em Búlgaro | MEDLINE | ID: mdl-25909135

RESUMO

The goal of the present paper is to discuss diagnosis, treatment approaches and histopathologic characteristics of breast cancer developing during pregnancy, based on our results and published literature data. We retrospectively evaluated clinical and pathologic features of tumors, treatment methods, decisions related to pregnancy and final outcome by eight pregnant patients with breast cancer. The patients' age varied from 26 to 36 years. At the last medical examination in October 2013, three among all eight patients were alive, two of them were without local and distant recurrence, and one patient has distant metastases and is carrying out a treatment. The aim of this paper was to discuss the characteristics of breast cancer developing during pregnancy. Retrospectively have been analyzed clinical-pathological characteristics of the tumors in eight pregnant women with breast cancer, the treatment, the management of the pregnancy, and the final outcome. The results are analyzed by comparing with data published in the literature.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Mama/patologia , Complicações Neoplásicas na Gravidez/patologia , Complicações Neoplásicas na Gravidez/terapia , Adulto , Mama/efeitos dos fármacos , Mama/efeitos da radiação , Mama/cirurgia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Feminino , Humanos , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico , Complicações Neoplásicas na Gravidez/cirurgia , Prognóstico , Radioterapia , Estudos Retrospectivos , Resultado do Tratamento
2.
Adv Colloid Interface Sci ; 145(1-2): 23-41, 2009 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-18804194

RESUMO

Element-specific techniques including near edge X-ray absorption fine structure, extended X-ray absorption fine structure and X-ray photoemission spectroscopy for the characterization of the carbon nanotube interfacial interactions are reviewed. These techniques involve soft and hard X-rays from the laboratory-based and synchrotron radiation facilities. The results provided information of how the nano-particles of catalysts are involved in the initial stage of nanotube growth, the nanotube chemical properties after purification, functionalization, doping and composite formation.

3.
Langmuir ; 22(15): 6696-700, 2006 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-16831015

RESUMO

The exfoliated (delaminated) structures of lamellar clays offer potential as precursors for the formation of various nanostructured materials. In this article, Lucentite and Laponite phyllosilicate clays, which both have empirical formulas of Na(0.33)[Mg(2.67)Li(0.33)Si4O10(OH)2] but differ in nanodimensions, have been exfoliated. Experiments were carried out for mixtures containing approximately 1 wt % phyllosilicate in a 5% aqueous solution of poly(acrylic acid) at different temperatures. X-ray diffraction and photoemission spectroscopy measurements for the solid products recovered after stirring the mixtures at 20 degrees C showed that the fully extended chains of poly(acrylic acid) were intercalated within the interlayer spaces between the silicate plates of the clays. At 85 degrees C, however, the clays were exfoliated and/or partially exfoliated. Photoemission spectroscopy also indicated that the exfoliated structures primarily consisted of silica nanoplates. 29Si nuclear magnetic resonance and oxygen K-edge near-edge X-ray absorption fine structure indicated that the surfaces of the plates were terminated by high concentrations of the silanol (-SiOH) groups, which created structural branches during intercalation. A model was developed in which intercalation and the removal of ions from the clays after the poly(acrylic acid) interactions reduced the electrostatic van der Waals forces between the plates. It was also shown that the formation of branches created a steric effect that inhibited the stacking of the plates. Together these resulted in exfoliation.

4.
J Colloid Interface Sci ; 297(2): 541-5, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16343522

RESUMO

A method for formation of polymer-clay nanocomposites involves dispersion of the nanometer silicate layers of clays into a solvent, followed by dispersion into polymers. The dispersion of layered silicates within solvents affects the structure and properties of the nanocomposites. We report the dispersion of organically modified clays, used for formation of nanocomposites with organic polymers, within a range of alcohol solvents. Experiments involved stirring a mixture containing approximately 1 wt% of alkylammonium-modified clays in n-alcohols with general molecular structure RnOH, where n represents the number of carbons of alkyl chains, varying from 2 to 8. The clays precipitated from the dispersion when RnOH solvents with n<5 were used, however, they formed gels for solvents with n5. The increased dispersion was related to the decrease of polarity and hydrogen bonding force within solvents. X-ray diffraction for the dispersed clays indicated that the interlayer spaces (1.8 nm), formed by regular stacking of the silicate layers, expanded to a maximum of 3.0 nm after treatment with RnOH with n5. The interlayer expansion was due to the intercalation of n-alcohol molecules within the interlayer spaces. It is suggested that the alkyl chains of n-alcohols remain parallel to the silicate surface in the intercalate. Preliminary experiments on the influence of these alcohol solvents on the intercalation of polyol (polyether) are also reported.

5.
Biomaterials ; 25(20): 4971-5, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15109858

RESUMO

Current bone graft materials are mainly produced from coralline hydroxyapatite (HAp). Due to the nature of the conversion process, commercial coralline HAp has retained coral or CaCO(3,) and the structure possesses nanopores within the inter-pore trabeculae, resulting in high dissolution rates. Under certain conditions these features reduce durability and strength and are not utilised where high structural strength is required. To overcome these limitations, a new coral double-conversion technique has been developed. The technique involves a two-stage application route where, in the first stage, complete conversion of coral to pure HAp is achieved. In the second, a new sol-gel-derived HAp nano-coating is directly applied to cover the micro- and nano-pores within the intra-pore material, whilst maintaining the large pores. Biaxial strength was improved two-fold due to this unique double treatment. This application is expected to result in enhanced durability and longevity due to the monophasic hydroxyapatite structure and strength in the physiological environment. It is anticipated that this new material can be applied to load-bearing bone graft applications where high strength requirements are pertinent.


Assuntos
Substitutos Ósseos/química , Cerâmica/química , Materiais Revestidos Biocompatíveis , Hidroxiapatitas/química , Transição de Fase , Próteses e Implantes , Animais , Austrália , Biomimética , Transplante Ósseo , Durapatita/química , Microscopia Eletrônica de Varredura , Nanotecnologia , Temperatura , Fatores de Tempo
7.
Akush Ginekol (Sofiia) ; 38(1): 20-3, 1999.
Artigo em Búlgaro | MEDLINE | ID: mdl-11965713

RESUMO

Six cases of primary treated endometrial cancer are included in this research work. Five of these women ended with tumour regression and 2 with pregnancies and deliveries of children. All of the women are still alive without having disease with mean follow-up period of 36.5 months (from 16 to 80 months). We consider that this is very promising method of treatment to offer y conservative treatment with high level of survival and possibility for having y child. Diagnostic and therapeutic data for the patients who are with early endometrial cancer and wish to have y child are analyised in this study. Four of the women were treated with GnRh-analogs-Zoladex and 2 with progestins-high doses.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Hormonais/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Hormônio Liberador de Gonadotropina/uso terapêutico , Progestinas/uso terapêutico , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adulto , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Feminino , Seguimentos , Humanos , Gravidez , Fatores de Tempo
9.
J Photochem Photobiol B ; 23(1): 35-42, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8021749

RESUMO

Four Zn(II) 2,3-naphthalocyanines (unsubstituted ZnNc1, tetracetylamido substituted ZnNc2, tetramino substituted ZnNc3 and tetramethoxy substituted ZnNc4) incorporated into unilamellar liposomes of dipalmitoylphosphatidylcholine have been injected intra-peritoneally (i.p.) (0.25-0.3 mg kg-1) to male C57/Black mice bearing a transplanted Lewis lung carcinoma. The pharmacokinetic investigations show that three of the four studied ZnNcs, 1, 2 and 4, are good tumor-localizers in Lewis lung carcinoma. The highest concentration is detected after ZnNc1 administration. The lowest tumor concentration as well as the lowest phototherapeutic effect were established with ZnNc3. In previous work it was shown that this ZnNc did not differ from the other three studied ZnNcs regarding the quantum yield of 1O2-formation and the photoinduced electron transfer. Obviously not only the good photochemical properties but also the tumor drug uptake can be an important factor of effective PDT. The biodistribution investigations also show that 72 h after drug injection, the skin concentration of the studied ZnNcs returns to the original base line. Indeed, we can expect that the skin photosensitivity will last for no longer than three days after PDT. The established higher drug concentration in the tumor rather than in the liver tissue (20 h after injection) shows again the tumor targeting selectivity of the applied liposome-sensitiser delivered procedure. Evaluating the PDT effect as reflected in the dynamics of the mean tumor diameter, we obtained unambiguous data on the potential capacity of ZnNcs 1,2,4 as PDT-photosensitisers. The data obtained from the assessment of the cytotoxic effect of PDT on the basis of the degree of induced necrosis, gave an adequate characterization of the tumor tissue destruction.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Metaloporfirinas/uso terapêutico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , 1,2-Dipalmitoilfosfatidilcolina , Animais , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Portadores de Fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Lasers , Lipossomos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Metaloporfirinas/administração & dosagem , Metaloporfirinas/farmacocinética , Camundongos , Camundongos Endogâmicos C57BL , Pele/metabolismo
10.
J Photochem Photobiol B ; 21(2-3): 155-65, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8301412

RESUMO

The aim of this investigation is to report the synthesis and fundamental photochemical properties of naphthalocyanines with potential interest for photodynamic therapy (PDT), as well as their pharmacokinetics and phototherapeutic effects in a tumor model. Four zinc naphthalocyanines (ZnNc), unsubstituted ZnNc 1, tetraacetylamido-substituted ZnNc 2, tetraamino-substituted ZnNc 3 and tetramethoxy-substituted ZnNc 4 absorbing around 760-770 nm, were synthesized. The dye-sensitized photo-oxidation of 1,3-diphenylisobenzofuran via 1O2 was studied in dimethylsulfoxide (DMSO). Quantum yields for this photoreaction are 0.135-0.164 and are relatively independent of the kind of substituent. In addition, the photoinduced electron transfer studied in N,N-dimethylformamide-water in the presence of methylviologen and mercaptoethanol is only slightly influenced by the kind of substituent. The pharmacokinetic properties of ZnNc 1 in hamsters bearing a transplanted rhabdomyosarcoma were studied using dipalmitoylphosphatidylcholine liposomes. Experimental PDT of rhabdomyosarcoma was carried out using liposome-delivered ZnNc 1-4. The phototherapeutic effect was evaluated by tumor photonecrosis, the mean tumor diameter during the observation period and the percentage of cured animals. The best effect was found after PDT with ZnNc 2 (50% of the treated animals were cured). A slightly lower effect was observed after application of ZnNc 4 (40% cured animals). No effect at all was noted after PDT with ZnNc 3 and a very low efficiency was found after treatment with ZnNc 1 as photosensitizer. Obviously, the photodynamic effect depends on the biological characteristics as well as on the nature of the substituents.


Assuntos
Metaloporfirinas/síntese química , Metaloporfirinas/toxicidade , Neoplasias Experimentais/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Animais , Cricetinae , Portadores de Fármacos , Indicadores e Reagentes , Lipossomos , Espectroscopia de Ressonância Magnética , Mesocricetus , Metaloporfirinas/farmacocinética , Estrutura Molecular , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/uso terapêutico , Teoria Quântica , Relação Estrutura-Atividade
11.
J Photochem Photobiol B ; 16(1): 83-9, 1992 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-1469513

RESUMO

Comparative pharmacokinetic studies in hamsters bearing an induced or first-generation transplanted rhabdomyosarcoma that were injected with liposome-incorporated zinc(II) phthalocyanine (ZnPc) show a higher drug concentration in the induced tumour. The selectivity of tumour targeting is underlined by the fact that, 24 h after injection, larger amounts of ZnPc are found in the tumour than in the liver. Photodynamic therapy investigations were carried out using 673 nm light from an argon-dye laser. On the basis of different assessment criteria (changes in mean tumour diameter with time, tumour mass regression, survival time of the treated groups of animals, and histological determination of the necrotic tissue) the photosensitizing effect of ZnPc appears to be comparable for both kinds of tumour in spite of the higher uptake of photosensitizer by the induced tumour.


Assuntos
Indóis/farmacocinética , Indóis/uso terapêutico , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/uso terapêutico , Fotoquimioterapia , Radiossensibilizantes/farmacocinética , Radiossensibilizantes/uso terapêutico , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/metabolismo , Zinco/farmacocinética , Zinco/uso terapêutico , Animais , Cricetinae , Isoindóis , Lasers , Lipossomos , Mesocricetus , Fatores de Tempo , Compostos de Zinco
12.
Cancer ; 64(3): 673-9, 1989 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-2743262

RESUMO

The cellular DNA content of 30 benign and 180 malignant breast tumors was analyzed by means of flow cytometry (FCM). All benign tumors exhibited a normal DNA content (diploid), whereas 65% of the malignant tumors showed an abnormal DNA content (aneuploid). The ploidy distribution of malignant tumors was bimodal with an increasing frequency near diploid DNA index (DI), and a second group had a DI ranging from triploid to tetraploid. In estimating the degree of malignancy eight independent histomorphologic and cytologic criteria were introduced. A good correlation was observed between DNA content abnormalities and the grade of differentiation of breast carcinomas. The percentage of S-phase cells of DNA aneuploid cell lines was significantly higher than in the diploid ones. The highly differentiated breast carcinomas (Grade 1) indicated lower S-phase values as compared to the undifferentiated (Grade 3) ones. S-phase values estimated by FCM were about two times higher than the 3H-thymidine labeling index (LI) obtained by an in vitro procedure. The data estimated in this study showed that DNA determinations as an adjunct to conventional histopathologic assessment may provide objective clinically relevant information with respect to the degree of malignancy and prognosis of patients with breast carcinoma.


Assuntos
Aneuploidia , Neoplasias da Mama/genética , DNA de Neoplasias/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Autorradiografia , Neoplasias da Mama/patologia , Divisão Celular , Diploide , Feminino , Citometria de Fluxo , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias
13.
Akush Ginekol (Sofiia) ; 28(3): 60-3, 1989.
Artigo em Búlgaro | MEDLINE | ID: mdl-2802084

RESUMO

The quick increase of morbidity, caused by the endometrial carcinoma in our country during recent 15 years from 5,2 to 16,5 per 100,000 raises acutely the question about effective primary and secondary prophylaxis. Having in mind the role of hyperestrogenemia in the etiology of endometrial carcinoma and the fact that the results from its treatment are determined basically by the degree of distribution of the tumor, the authors think that it is necessary fight for rational feeding, timely treatment of the disease with hyperestrogenemia and prophylactic therapy with gestagens. Cytologic examination of aspirate, obtained from the uterine cavity, is proposed as screening method for women of the risk groups. A scheme of management of women with pathological R3-5 group is proposed.


Assuntos
Neoplasias Uterinas/prevenção & controle , Bulgária , Estrogênios/sangue , Feminino , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência , Prevenção Primária , Fatores de Tempo , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/epidemiologia
14.
Cryobiology ; 22(1): 35-9, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3979076

RESUMO

During cryopreservation of leukocytes, a great part of the granulocytes is injured. The latter is responsible for aggregate formation in the suspension and a loss in the number of preserved cells. The formation of aggregates in the suspension is potentiated in the presence of serum in the cryoprotective medium. On the other hand, the presence of sugar (sucrose, lactose, dextrose) in the washing solution diminishes the aggregate formation, the latter effect being directly proportional to the final concentration of the sugar in the suspension. The aggregates contain mainly cells and very rarely amorphous or fibrous zones. They appear only in the presence of serum. Their formation is not connected with presence of traces of fibrinogen in the serum.


Assuntos
Preservação de Sangue , Leucócitos/citologia , Carboidratos , Agregação Celular , Crioprotetores , Congelamento , Humanos , Técnicas In Vitro , Soluções
15.
Artigo em Inglês | MEDLINE | ID: mdl-6202598

RESUMO

Erythrophagocytosis is conditioned by serum immunoglobulins. The extent of phagocytosis depends on the haematocrit of the red cell suspension pretreated with formaldehyde. The higher the haematocrit value, the lower will be the extent of phagocytosis. Phagocytosis of white blood cells pretreated with formaldehyde by granulocytes and monocytes is conditioned mainly by a thermolabile fraction of the serum, probably the complement.


Assuntos
Eritrócitos/imunologia , Formaldeído/farmacologia , Isoanticorpos/fisiologia , Leucócitos/imunologia , Proteínas Opsonizantes/fisiologia , Fagocitose , Fenômenos Fisiológicos Sanguíneos , Preservação de Sangue , Ativação do Complemento , Eritrócitos/efeitos dos fármacos , Temperatura Alta , Humanos , Leucócitos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos
16.
Artigo em Inglês | MEDLINE | ID: mdl-6182070

RESUMO

Data are presented for percentage of recovery, survival time (T1/2) and mode of sequestration of erythrocytes from ACD [disodium citrate 95 mmol/l and glucose (C6H12O6 X H2O)] 152 mmol/l or ACD--adenine or adenine + guanosine (pH ranging from 5.0 to 5.6) preserved blood for 35 days at 4-8 degrees C (277-281 K). With the availability of guanosine in 0.25 mmol/l or 0.5 mmol/l final concentration in ACD + 0.25 or 0.5 mmol/l adenine preserved blood a positive effect can be exerted on erythrocyte 24 hrs recovery and survival time (T1/2). This effect is particularly evident when pH of the preservative solution is raised to 5.6. Final concentrations of 0.25 mmol/l adenine and guanosine in ACD preserved blood (whole or packed erythrocytes, pH 5.6, Hct. 0.73 or 0.61) are sufficient to ensure 35 days of storage at 4-8 degrees C (277-281 K).


Assuntos
Adenina/farmacologia , Preservação de Sangue/métodos , Eritrócitos/efeitos dos fármacos , Guanosina/farmacologia , Transfusão de Sangue , Radioisótopos de Cromo , Citratos , Ácido Cítrico , Envelhecimento Eritrocítico , Transfusão de Eritrócitos , Glucose , Humanos
18.
Artigo em Inglês | MEDLINE | ID: mdl-6182072

RESUMO

Platelet concentrates amounting to 142 X 10(9) +/- 11 X 10(9) cells are prepared by cytopheresis from one liter of blood. Ten of the concentrates are labelled with 51Cr and reinfused autologously. The other ten concentrates are frozen with a controlled rate freezer in a medium containing 10% DMSO and 5% glucose for 7 days at -196 degrees C. The fresh platelets have a 51Cr 24 hrs. recovery of 68 +/- 7% and a survival rate (T 1/2) of 10 +/- 1 days. The frozen preserved platelets have a 51Cr 24 hrs. recovery of 54 +/- 6.1%, a T 1/2 of 8.1 days, and significantly increased liver sequestration. There is a correlation between the reversal reaction in vitro after hypotonic shock and the 51Cr 24 hrs. in vivo recovery of fresh platelets and the 51Cr 1st hr. recovery of frozen platelets.


Assuntos
Plaquetas/fisiologia , Preservação de Sangue/métodos , Plaquetas/citologia , Transfusão de Sangue Autóloga , Sobrevivência Celular , Radioisótopos de Cromo , Congelamento , Humanos , Técnicas In Vitro , Fígado/citologia , Miocárdio/citologia , Transfusão de Plaquetas , Choque/sangue , Baço/citologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-6157617

RESUMO

A method has been described for removing leukocytes and thrombocytes from preserved ACD blood and from packed red cells of the same type of blood. A system has been used comprising two connected plastic bags model "Fenval". The leukocyte and thrombocyte removal is performed by two consecutive procedures, each comprising centrifugation with subsequent fast sedimentation of erythrocytes. No filters are needed. 97.3 +/- 3.04% leukocyte removal and 96.90 +/- 5.96% thrombocyte removal as regards the preserved blood and 95.65 +/- 8.70% leukocyte removal and 98.44 +/- 0.70% thrombocyte removal as regards the packed red cells have been achieved.


Assuntos
Plaquetas , Separação Celular/métodos , Leucócitos , Preservação de Sangue , Centrifugação , Hematócrito , Humanos
20.
Artigo em Alemão | MEDLINE | ID: mdl-50971

RESUMO

In 100 healthy persons and 38 patients with idiopathic thrombocytopenic purpura (ITP) the morphology of thrombocytes was examined according to BREDDIN. The survival time of the marked thrombocytes and their place of sequestration was determined in the patients and in 17 voluntary persons. A correlation was found to exist between the morphology of thrombocytes and those four forms of ITP which could be limited by means of radiometric methods. Moreover, a certain degree of dependence was found between the thrombocyte sequestration place and the presence of antibodies.


Assuntos
Plaquetas/patologia , Adesividade Plaquetária , Púrpura Trombocitopênica/diagnóstico , Aglutininas/análise , Sobrevivência Celular , Humanos , Púrpura Trombocitopênica/cirurgia , Esplenectomia , Toxinas Biológicas/análise
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