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1.
J Photochem Photobiol B ; 189: 74-80, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30316028

RESUMO

The adsorption and photodynamic efficiency of 5,10,15,20-tetrakis(p-sulfonatophenyl)porphyrin (H2TPPS4) on bilayer lipid membranes (BLM) have been studied. The adsorption of H2TPPS4 on BLM leads to rising of the potential drop on the membrane/water interface which has been detected either by the intramembrane field compensation (IFC) method, or as ζ-potential of liposomes measured by the dynamic light scattering method. The dependence of this potential on the concentration of H2TPPS4 and KCl in the solution can be described in the frame of Gouy-Chapman model of diffuse double layer assuming that the molecules of H2TPPS4 adsorb on the surface of BLM as an anions with four charged groups. The potential disappeared when the pH of solution decreased from 6 to 3 allowing the conclusion that the protonated forms of H2TPPS4 can not adsorb on the BLM probably due to change of conformation or aggregation of the molecules. The photodynamic efficiency of H2TPPS4 was evaluated by measuring the rate of damage of the targets - molecules of styryl dye (di-4-ANEPPS) by singlet oxygen generated under illumination on the surface of BLM. This rate was proportional to the surface density of H2TPPS4 molecules on the membrane which was determined from the change of surface charge of the membrane due to adsorption of the H2TPPS4. These results indicate that the di-4-ANEPPS molecules are damaged by singlet oxygen generated by monomers of H2TPPS4 molecules adsorbed on the membrane. The rate of oxidation of di-4-ANEPPS molecules adsorbed on the same (cis) side of the membrane together with the H2TPPS4 molecules was either the same or higher than that when di-4-ANEPPS molecules were adsorbed on opposite (trans) side. It indicates that the quenching of singlet oxygen by the di-4-ANEPPS molecules at cis side of the membrane was negligible, in contrast to our earlier study when singlet oxygen was generated by aluminum(III) phthalocyanines with one or two peripheral sulfo groups. The difference between these phthalocyanines and H2TPPS4 was explained by their different adsorption depth in the membrane.


Assuntos
Bicamadas Lipídicas/química , Porfirinas/química , Adsorção , Corantes Fluorescentes , Potenciais da Membrana , Membranas Artificiais , Compostos de Piridínio/química , Oxigênio Singlete/química , Propriedades de Superfície
2.
Sci Rep ; 8(1): 14000, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30228297

RESUMO

Photodynamic therapy uses photosensitizers (PS) to kill cancer cells by generating reactive oxygen species - like singlet oxygen (SO) - upon illumination with visible light. PS membrane anchoring augments local SO concentration, which in turn increases photodynamic efficiency. The latter may suffer from SO's escape into the aqueous solution or premature quenching. Here we determined the time constants of SO escape and quenching by target molecules to be in the nanosecond range, the former being threefold longer. We confined PS and dipolar target molecules either to different membrane monolayers or to the same leaflet and assessed their abundance by fluorescence correlation spectroscopy or membrane surface potential measurements. The rate at which the contribution of the dipolar target molecules to membrane dipole potential vanished, served as a measure of the photo-oxidation rate. The solution of the reaction-diffusion equations did not indicate diffusional rate limitations. Nevertheless, reducing the PS-target distance increased photodynamic efficiency by preventing other SO susceptible moieties from protecting the target. Importantly, our analytical model revealed a fourfold difference between SO generation rates per molecule of the two used PSs. Such analysis of PS quantum yield in a membrane environment may help in designing better PSs.

3.
Arkh Patol ; 79(4): 40-47, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28791998

RESUMO

Mammary-like glands are a normal anatomical component of the anogenital region. The tumors occurring in them morphologically mimic the similar diseases of the breast. The paper presents a case of vulvar fibroadenoma with leaf-like outgrowths and apocrine metaplasia in a 38-year-old female patient. It describes the clinical and morphological characteristics of fibroadenomas and benign phyllodes tumors in the anogenital region.


Assuntos
Fibroadenoma/patologia , Hiperplasia/patologia , Tumor Filoide/patologia , Neoplasias Vulvares/patologia , Adulto , Feminino , Fibroadenoma/diagnóstico , Humanos , Hiperplasia/diagnóstico , Tumor Filoide/diagnóstico
4.
Arkh Patol ; 79(3): 47-52, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28631716

RESUMO

Mammary-like glands are a normal anatomical component of the anogenital region and can give rise to many benign and malignant tumors that morphologically mimic the similar diseases of the breast. The literature review is complemented by a description of 199 cases of malignant tumors of mammary-like glands. The paper presents the clinical and morphological characteristics of various malignant tumors of mammary-like glands, including extramammary Paget's disease, ductal, tubulolobular, adenoid cystic adenocarcinoma, low-grade phyllodes tumor, etc.


Assuntos
Carcinoma/patologia , Doença de Paget Extramamária/patologia , Neoplasias das Glândulas Sudoríparas/patologia , Adenomas Tubulares de Glândulas Sudoríparas/patologia , Neoplasias Vulvares/patologia , Feminino , Humanos
5.
Arkh Patol ; 79(1): 43-51, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28295007

RESUMO

Anogenital mammary-like glands represent a normal anatomic constituent of the anogenital area and may give rise to many benign and malignant tumors that morphologically mimic similar breast diseases. The literature review is complemented by a description of 286 cases of benign tumors and tumor-like processes in the mammary-like glands. The paper presents the clinical and morphological characteristics of papillary hidradenoma, fibroadenoma, benign phyllodes tumor, lactating adenoma, sclerosing adenosis, pseudoangiomatous stromal hyperplasia, etc.


Assuntos
Acrospiroma/patologia , Neoplasias da Mama/patologia , Mama/patologia , Neoplasias/patologia , Acrospiroma/diagnóstico , Adenoma/diagnóstico , Adenoma/patologia , Neoplasias da Mama/classificação , Neoplasias da Mama/diagnóstico , Feminino , Fibroadenoma/diagnóstico , Fibroadenoma/patologia , Humanos , Lactação/fisiologia , Neoplasias/classificação , Neoplasias/diagnóstico , Tumor Filoide/diagnóstico , Tumor Filoide/patologia , Organização Mundial da Saúde
6.
Arkh Patol ; 77(6): 50-53, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26841650

RESUMO

Autopsy study of an 80-year-old man has identified his renal tumor metastasizing to the heart, lung, and liver as urothelial car- cinoma; at the same time some cells in the main tumor and all cells in the metastases had a signet-ring phenotype, but neither mucicarcimine nor alcian blue stained the cell cytoplasm. The paper provides the histological and immunohistochemical pattern of the tumor and emphasizes its exclusive rarity. Attention is drawn to the possibility of signet-ring cell transformation in the cells of different tumors, including nonepithelial ones.


Assuntos
Carcinoma de Células Renais/ultraestrutura , Carcinoma de Células em Anel de Sinete/ultraestrutura , Urotélio/ultraestrutura , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/patologia , Carcinoma de Células em Anel de Sinete/patologia , Humanos , Masculino , Urotélio/patologia
7.
Ross Fiziol Zh Im I M Sechenova ; 100(11): 1297-302, 2014 Nov.
Artigo em Russo | MEDLINE | ID: mdl-25665408

RESUMO

In this paper, we study the relation between the electrophoretic mobility of erythrocytes (EPME) and the activity of Na,K-ATPase of erythrocytes under the action of different types of stress factors (immobilization, hypoxia, radiation exposure), as well as the introduction of stress implementing agents (adrenaline, cortisol, bee and toad venom) rats. Activity of Na,K-ATPase and the change of EPME washed erythrocytes were examined through 15, 120 min and 24 hours after exposure. Found that at the initial stage (15 min after a stress-exposure) decrease of EPME associated with increased enzyme activity and further increase of EPME takes place on the background of the decrease of activity of Na,K-ATPase in all types of alterations, except the actions toad venom and cortisol. Toad venom and cortisol led to reduced activity of Na,K-ATPase and increase of EPME.


Assuntos
Eritrócitos/citologia , Hipóxia/enzimologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Venenos de Anfíbios/farmacologia , Animais , Animais não Endogâmicos , Venenos de Abelha/farmacologia , Células Cultivadas , Eletroforese , Epinefrina/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Eritrócitos/efeitos da radiação , Feminino , Raios gama , Hidrocortisona/farmacologia , Hipóxia/fisiopatologia , Imobilização , Oxigênio/farmacologia , Ratos , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/efeitos da radiação , Fatores de Tempo
8.
Arkh Patol ; 75(1): 30-3, 2013.
Artigo em Russo | MEDLINE | ID: mdl-23805470

RESUMO

The paper describes a rare case of mediastinal epithelioid hemangioendothelioma characterized by a population of fusiform cells, metaplastic osteogenesis, and aggressive behavior. A 5.5x4-cm encapsulated mass was found in the anterior mediastinum of a 19-year-old female patient. A bone density tumor was sealed with lung tissue and it occluded the lumen of the left subclavian vein. Microscopically, the tumor was composed of foci of the so-called "blister cells" typical of epithelioid hemangioendothelioma, anastomosing chains of epithelioid cells in the microhyaline stroma, diffusely located bone trabeculae, and hemorrhagic stroma. Fusiform cells were present in considerable quantities. A moderate cellular and nuclear polymorphism occurred when mitotic figures were absent. Tumor cells expressed Flil, vimentin, CD31, and CD34. Multiple metastases were detected in the liver and lung. They had the similar morphology.


Assuntos
Regulação Neoplásica da Expressão Gênica , Hemangioendotelioma , Neoplasias Hepáticas , Neoplasias Pulmonares , Neoplasias do Mediastino , Proteínas de Neoplasias/biossíntese , Adulto , Idoso , Feminino , Hemangioendotelioma/metabolismo , Hemangioendotelioma/patologia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Masculino , Neoplasias do Mediastino/metabolismo , Neoplasias do Mediastino/patologia , Pessoa de Meia-Idade , Metástase Neoplásica
9.
Zookeys ; (155): 61-87, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22291512

RESUMO

A new genus (Borinken) and five new species (Borinken elyunque, Distigmoptera chamorrae, Kiskeya elyunque, Ulrica eltoro, and Ulrica iviei) from Puerto Rico are described and illustrated. A keyto all West Indian Monoplatini genera is provided, as are keys to all speciesof Kiskeya and to the speciesof Ulrica from Puerto Rico. A list of the flea beetle genera, along with the number of species and some of the faunal features is presented and discussed for the West Indies.

10.
Mol Biol (Mosk) ; 43(5): 866-81, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19899634

RESUMO

Contemporary views on the phylogeny of arthropods are at odds with the traditional system, which recognizes four independent arthropod classes: Chelicerata, Crustacea, Myriapoda and Insecta. There is compelling evidence that insects in fact comprise a monophyletic lineage with Crustacea within a larger clade of Pancrustacea (=Tetraconata). Which crustacean group is the closest living relative of insects remains an open question. Recent phylogenetic analyses based on multiple genes suggest their sistership with "lower" crustaceans, the Branchiopoda. This relationship was often impeached to be caused by the long branch attraction artifact. We analyzed concatenated data on 77 ribosomal proteins, elongation factor 1 alpha (EF1A), initiation factor 5 alpha (alF5A) and other selected nuclear and mitochondrial proteins. Nuclear protein data supports the monophyly of Hexapoda, the clade uniting entognath and ectognath insects. Hexapoda and Branchiopoda comprise a monophyletic lineage in most analyses. Maxillopoda occupies the sister position to the Hexapoda + Branchiopoda. "Higher" crustaceans, the Malacostraca, in most reconstructions comprise a more basal lineage withinthe Pancrustacea. Molecular synapomorphies in low homoplastic regions are found for the clades Hexapoda Branchiopoda + Maxillopoda and the monophyletic Malacostraca containing the Phyllocarida. Therefore, the sistership of Hexapoda and Branchiopoda and their position within Entomostraca may in fact represent bona fide phylogenetic relationships.


Assuntos
Genoma de Inseto/fisiologia , Proteínas de Insetos/genética , Insetos/classificação , Insetos/genética , Filogenia , Animais
12.
Biochemistry (Mosc) ; 72(12): 1313-23, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18205615

RESUMO

Fifty-six nuclear protein coding genes from Taxonomically Broad EST Database and other databases were selected for phylogenomic-based examination of alternative phylogenetic hypotheses concerning intergroup relationship between multicellular animals (Metazoa) and other representatives of Opisthokonta. The results of this work support sister group relationship between Metazoa and Choanoflagellata. Both of these groups form the taxon Holozoa along with the monophyletic Ichthyosporea or Mesomycetozoea (a group that includes Amoebidium parasiticum, Sphaeroforma arctica, and Capsaspora owczarzaki). These phylogenetic hypotheses receive high statistical support both when utilizing whole alignment and when only 5000 randomly selected alignment positions are used. The presented results suggest subdivision of Fungi into Eumycota and lower fungi, Chytridiomycota. The latter form a monophyletic group that comprises Chytridiales+Spizellomycetales+Blastocladiales (Batrachochytrium, Spizellomyces, Allomyces, Blastocladiella), contrary to the earlier reports based on the analysis of 18S rRNA and a limited set of protein coding genes. The phylogenetic distribution of genes coding for a ubiquitin-fused ribosomal protein S30 implies at least three independent cases of gene fusion: in the ancestors of Holozoa, in heterotrophic Heterokonta (Oomycetes and Blastocystis) and in the ancestors of Cryptophyta and Glaucophyta. Ubiquitin-like sequences fused with ribosomal protein S30 outside of Holozoa are not FUBI orthologs. Two independent events of FUBI replacement by the ubiquitin sequence were detected in the lineage of C. owczarzaki and in the monophyletic group of nematode worms Tylenchomorpha+Cephalobidae. Bursaphelenchus xylophilus (Aphelenchoidoidea) retains a state typical of the rest of the Metazoa. The data emphasize the fact that the reliability of phylogenetic reconstructions depends on the number of analyzed genes to a lesser extent than on our ability to recognize reconstruction artifacts.


Assuntos
Genes/genética , Filogenia , Animais , Sequência de Bases , Bases de Dados Genéticas , Células Eucarióticas/metabolismo , Evolução Molecular , Etiquetas de Sequências Expressas , Humanos , Modelos Genéticos , RNA Ribossômico 18S/genética , Proteínas Ribossômicas/genética
13.
Genetika ; 40(12): 1714-6, 2004 Dec.
Artigo em Russo | MEDLINE | ID: mdl-15648156

RESUMO

Fragments of the nuclear and mitochondrial genes for the large-subunit rRNA were compared for Trichoplax sp. and T. adhaerens. High similarity was observed for their sequences, suggesting that different Trichoplax isolates belong to one species.


Assuntos
Núcleo Celular/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Invertebrados/genética , RNA Ribossômico/genética , Animais , Especificidade da Espécie
15.
Biochim Biophys Acta ; 736(1): 109-18, 1983 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-6317027

RESUMO

Compound 48/80, a condensation product of N-methyl-p-methoxyphenethylamine with formaldehyde, is composed of a family of cationic amphiphiles differing in the degree of polymerization. Compound 48/80 was found to be a potent inhibitor of the calmodulin-activated fraction of brain phosphodiesterase and red blood cell Ca2+-transport ATPase, with IC50 values of 0.3 and 0.85 micrograms/ml, respectively. However, the basal activity of both enzymes is not at all suppressed by the drug at concentrations up to 300 micrograms/ml. Inhibition of Ca2+ transport into inside-out red blood cell vesicles by compound 48/80 follows a similar pattern in that basal, calmodulin-independent, transport is also not affected by the drug. Kinetic analysis revealed that the stimulation of Ca2+-transport ATPase induced by calmodulin is inhibited by compound 48/80 according to a competitive mechanism. It was demonstrated that the inhibitory constituents of compound 48/80 bind to calmodulin in a Ca2+-dependent fashion. Comparison of the specificity of several anti-calmodulin drugs showed that compound 48/80 is the most specific inhibitor of the calmodulin-dependent fraction of red blood cell Ca2+-transport ATPase that has been described hitherto. In addition, compound 48/80 was found to be a rather specific inhibitor of the calmodulin-induced activation of Ca2+-transport ATPase when compared with the stimulation induced by an anionic amphiphile or by limited proteolysis. Half-maximal inhibition of the activity stimulated by oleic acid or mild tryptic digestion required 8- and 32-times higher concentrations of compound 48/80, respectively, compared with the calmodulin-dependent fraction of the ATPase activity. Moreover, calmodulin-independent systems as rabbit skeletal muscle sarcoplasmic reticulum Ca2+-transport ATPase or calf cardiac sarcolemma (Na+ + K+)-transport ATPase are far less influenced by compound 48/80 as compared with trifluoperazine and calmidazolium. Because of its high specificity compound 48/80 is proposed to be a promising tool for studying calmodulin-dependent processes.


Assuntos
Calmodulina/antagonistas & inibidores , p-Metoxi-N-metilfenetilamina/farmacologia , Animais , Encéfalo/enzimologia , ATPases Transportadoras de Cálcio/sangue , Eritrócitos/enzimologia , Diester Fosfórico Hidrolases/metabolismo , Coelhos , Retículo Sarcoplasmático/enzimologia , ATPase Trocadora de Sódio-Potássio/metabolismo
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