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1.
Kardiologiia ; 57(3): 46-50, 2017 Mar.
Artigo em Russo | MEDLINE | ID: mdl-28762935

RESUMO

OBJECTIVE: to determine levels of galectin-3, markers of renal dysfunction, and plasma oxidative stress; to assess their correlation in patients with chronic heart failure (CHF) of various severity. MATERIAL AND METHODS: We included in this study 157 CHF patients (with documented prior myocardial infarction. Patients were divided into 3 groups according to their NYHA functional class (group 1 - class II n=60, group 2 - class III n=52, group 3 - class IV n=45). All patients underwent clinical examination, echocardiography. Laboratory parameters included measurement of plasma levels of galectin-3, NT-proBNP, as well as markers of oxidative stress (oxidized low density lipoprotein cholesterol [oxLDLC], SH-groups) and renal dysfunction (creatinine, uric acid, cystatin-C). RESULTS: The level of galectin-3 (median) in groups 1, 2, and 3 was 10, 19 and 38 ng/ml respectively. There were significant differences between groups (p<0,001). In all groups levels of galectin-3 significantly (p<0.01) correlated with those of oxLDL (positively) and SH-groups (negatively): r1=0.52, r2=0.59, r3=0.63, p<0.01, and r1=-0.58, r2=-0.65, r3=-0.71, respectively. Correlation analysis also revealed close and moderate correlations between galectin-3 and cystatin-C, glomerular filtration rate, and uric acid. CONCLUSIONS: In patients with CHF and prior myocardial infarction plasma concentration of galectin-3 was associated with severity of CHF and significantly correlated with markers of renal dysfunction and plasma oxidative stress.


Assuntos
Biomarcadores , Galectina 3 , Insuficiência Cardíaca/sangue , Estresse Oxidativo , Proteínas Sanguíneas , Doença Crônica , Ecocardiografia , Feminino , Galectinas , Taxa de Filtração Glomerular , Humanos , Lipoproteínas LDL , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos
2.
Gig Sanit ; 94(5): 36-9, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26625613

RESUMO

In 2013-2014, there was performed the study of the soil in the territory of the city of Novokuibyshevsk. The concentrations of heavy metals and petroleum products on the territory of the industrial zone of the city of Novokuibyshevsk were determined. The evaluation of concentrations ofanthropogenic toxicants was carried out in Novokuibyshevsk by means of laboratory monitoring of environmental pollution. The obtained values were compared with the MPC or in the absence of MPC--with tentatively permissible concentrations (TPC) of chemicals in soil background concentrations in the Volga region of Samara region, as well as with previous studies of the soil of the city of Novokuibyshevsk in 2005. The studies revealed that in 2014, if compared with 2005, concentrations of heavy metals in soil on the territory of the industrial zone of the city of Novokuibyshevsk and within the city border decreased. There were obtained significant differences in the soil content ofcadmium, copper, lead, Nickel and zinc in 2005 and 2013-2014. Unlike the content of salts of heavy metals, the content of petroleum products in the soil over the past 9 years had tended to increase. The maximum concentration of petroleum products was detected in the industrial zone of CHP-1. The number of samples with extremely high pollution rised from 4% to 8%, with high pollution--from 10% to 12%. Also, an increase in the number of samples with the level of 2-20 background values accounted from 56% to 66%. The gain in concentrations of petroleum in the soil on the territory of the city of Novokuibyshevsk was associated not only with the activity of the enterprises of oil refining and petrochemical industry, but also with the elevating number of road transport.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Indústria de Petróleo e Gás , Poluição por Petróleo/análise , Poluentes do Solo/análise , Solo/normas , Federação Russa , Urbanização
3.
Vopr Pitan ; 80(2): 52-7, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21692350

RESUMO

Substantiate the need for long-term program of sanitation the diet of the population of the Samara Region. A systemic analysis of actual nutrition of different population groups in the region showed an excessive consumption of fats and added sugar--the main risk factors of obesity, cardiovascular diseases and diabetes mellitus. The risks of inadequate consumption of vitamins B, calcium, iron, caused by the irrational combination of the foodstuff use, are revealed.


Assuntos
Abastecimento de Alimentos , Alimentos , Programas Gente Saudável/normas , Estado Nutricional , Feminino , Humanos , Masculino , Valor Nutritivo , Federação Russa
4.
Gig Sanit ; (4): 83-6, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20873273

RESUMO

The educational medium in varying secondary educational establishments of Samara was comparatively analyzed in accordance with the sanitary regulations SanPiN 2.4.2.1178-02 "Hygienic requirements for teaching conditions in general educational establishments". The study demonstrated that the teaching conditions at schools primarily required that school load be rationalized and the ergonomic parameters offurniture and artificial illumination improved.


Assuntos
Instituições Acadêmicas/normas , Estudantes , Ensino/organização & administração , Cidades , Humanos , Higiene/normas , Federação Russa , Instituições Acadêmicas/organização & administração , Ensino/normas , População Urbana
5.
Gig Sanit ; (1): 42-3, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19358353

RESUMO

Nutrition is one of the most important determinants of human health. The investigation has determined the pattern of actual nutrition of the Samara Region, its influence on the occurrence of cardiovascular, endocrine, urogenital, and musculoskeletal, and digestive diseases. Emphasis is placed on unbalanced diets excluding meat, by increasing the consumption of bread and cereals, which is a universal factor for the development of visceral diseases. Balanced nutrition using full-value natural products in the optimum ratio is a major condition for health preservation and a means for prevention of the development of various diseases.


Assuntos
Doenças Cardiovasculares/etiologia , Doenças do Sistema Digestório/etiologia , Doenças do Sistema Endócrino/etiologia , Doenças Urogenitais Femininas/etiologia , Doenças Urogenitais Masculinas/etiologia , Doenças Musculoesqueléticas/etiologia , Distúrbios Nutricionais/complicações , Doenças Cardiovasculares/epidemiologia , Doenças do Sistema Digestório/epidemiologia , Doenças do Sistema Endócrino/epidemiologia , Feminino , Doenças Urogenitais Femininas/epidemiologia , Humanos , Masculino , Doenças Urogenitais Masculinas/epidemiologia , Morbidade/tendências , Doenças Musculoesqueléticas/epidemiologia , Distúrbios Nutricionais/epidemiologia , Fatores de Risco , Federação Russa/epidemiologia
6.
J Exp Bot ; 56(413): 1039-47, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15710632

RESUMO

AtMHX is an Arabidopsis tonoplast transporter that can exchange protons with Mg2+ and Zn2+ ions. This transporter, which may play a role in ion homeostasis of plants, is encoded by a single gene in Arabidopsis. The molecular mechanisms that regulate the expression of this transporter are practically unknown. While AtMHX transcript can be easily visualized, expression of the corresponding protein is apparently low. To understand whether AtMHX expression is repressed at the translational level, the 5' untranslated region (5' UTR) of this gene was fused to reporter genes. In vitro analyses showed that the 5' UTR of AtMHX can repress the translation of downstream coding sequences. The major cause of the repression was efficient initiation at an upstream open-reading-frame (uORF) included in the 5' UTR. Although the sequence context of the upstream AUG (uAUG) codon was highly unfavourable, it was recognized by over 90% of the scanning ribosomes both in vitro and in vivo. The inhibitory effect of the uORF was mediated by imposing the need for reinitiation and not by ribosome stalling, as the inhibition was not dependent on the amino-acid sequence of the uORF peptide. The efficiency of reinitiation was low. The in vivo studies, carried out with transiently transformed tobacco plants, indicated that alternations in the Mg2+ or Zn2+ levels did not affect the rate of translation. These data suggest that AtMHX expression is repressed by the 5' UTR of its gene.


Assuntos
Regiões 5' não Traduzidas/fisiologia , Antiporters/biossíntese , Proteínas de Arabidopsis/biossíntese , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Fases de Leitura Aberta/fisiologia , Transporte Biológico Ativo , Magnésio/fisiologia , Plantas Geneticamente Modificadas , Biossíntese de Proteínas , Sódio/fisiologia , Nicotiana , Transcrição Gênica , Zinco/fisiologia
7.
Vopr Pitan ; 74(6): 42-5, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16605010

RESUMO

The results of study on substantiating the possibilities of the use of flavolignans of Silybum marianum (L.) Gaertn. with a purpose to create a new fat product--butter fortified by an "Liguid extract Silybum marianum (L.) Gaertn." are being discussed. Slowdown of peroxidation process is revealed in fortified butter in comparison with ordinary butter. With the help of spectrometry method higher content of flavolignans was deteeted in fortified butter (converting to silibin--the main component of "Liguid Exstract Silybum marianum (L) Gaertn"), what allows to speak about increase of its potential therapeutic effect.


Assuntos
Manteiga , Flavonolignanos/química , Alimentos Fortificados , Silybum marianum/química , Flavonolignanos/isolamento & purificação , Silibina , Silimarina/química , Silimarina/isolamento & purificação
9.
Gastroenterology ; 120(2): 561-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11159897

RESUMO

The relationship between the development of the enteric nervous system and interstitial cells of Cajal (ICC) in the human small intestine was investigated in a full-term infant who presented with intestinal pseudo-obstruction. Immunohistochemistry revealed absence of enteric nerves and ganglia but abundant c-Kit immunoreactivity associated with Auerbach's plexus (ICC-AP). However, c-Kit immunoreactivity associated with the deep muscular plexus (ICC-DMP) and intermuscular ICC was absent. Electron microscopy showed ICC-AP with a normal ultrastructure; ICC-DMP were seen but were severely injured, suggesting degeneration. In vitro recording of intestinal muscle showed slow wave activity as well as response to cholinergic stimulation. Fluoroscopic examination of the small bowel showed a variety of motor patterns, including rhythmic, propagating contractions. In conclusion, total absence of enteric nerves was associated with absence of normal ICC-DMP. However, a normal musculature, including a network of ICC-AP, allowed for generation of rhythmic, propagating contractile activity, suggesting the presence of functional motor activity.


Assuntos
Sistema Nervoso Entérico/anormalidades , Intestino Delgado , Relógios Biológicos/fisiologia , Sistema Nervoso Entérico/ultraestrutura , Evolução Fatal , Esvaziamento Gástrico/fisiologia , Motilidade Gastrointestinal/fisiologia , Humanos , Recém-Nascido , Intestino Delgado/citologia , Intestino Delgado/embriologia , Intestino Delgado/inervação , Masculino , Potenciais da Membrana/fisiologia , Microscopia Eletrônica , Neurônios Motores/fisiologia , Músculo Liso/inervação , Músculo Liso/fisiologia , Músculo Liso/ultraestrutura
10.
Gastroenterology ; 119(6): 1590-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11113080

RESUMO

BACKGROUND & AIMS: Interstitial cells of Cajal (ICC) play an important role in the control of gastrointestinal motility. We aimed to determine a potential role for ICC in the pathophysiology of inflammation-induced motor disorders. METHODS: Effects of Trichinella spiralis infection on electrical pacemaker activity, the structure of ICC associated with Auerbach's plexus, and in vivo motor patterns were studied in the mouse small intestine. RESULTS: Between days 1 and 15 after infection, structural damage occurred in the network of ICC, particularly in the processes connecting ICC to each other and to smooth muscle cells. This was associated with desynchronization of electrical pacemaker activity. Abnormal slow wave activity occurred, including doubling of frequency and electrical quiescence, leading to the development of ectopic pacemaker activity in vivo. In vivo motor patterns in the small intestine changed from consistent peristaltic contractile activity in control animals to periods of quiescence alternating with both orally and aborally propagating contractile activity in the presence of inflammation. Sixty days after infection, all parameters studied had returned to normal values. CONCLUSIONS: Inflammation-induced alterations in the network of ICC of the small intestine associated with Auerbach's plexus lead to disorganization of motor patterns. Because of the strong temporal correlation between damage to the ICC network, electrical uncoupling, the appearance of ectopic pacemaker activity, and the occurrence of retrograde peristalsis, it is concluded that ICC can play a major role in inflammation-induced motor disturbances.


Assuntos
Enterite/fisiopatologia , Motilidade Gastrointestinal , Intestino Delgado/fisiopatologia , Animais , Relógios Biológicos , Eletrofisiologia , Enterite/diagnóstico por imagem , Enterite/parasitologia , Enterite/patologia , Trânsito Gastrointestinal , Técnicas In Vitro , Intestino Delgado/diagnóstico por imagem , Intestino Delgado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Músculo Liso/patologia , Plexo Mientérico/patologia , Plexo Mientérico/fisiopatologia , Peristaltismo , Radiografia , Trichinella spiralis , Triquinelose
11.
Prikl Biokhim Mikrobiol ; 36(3): 278-86, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10867945

RESUMO

In order to reduce the total enzyme consumption in high-solids static hydrolysis of nonwashed steam-exploded willow Salix caprea by mixed cellulase of Trichoderma reesei + Aspergillus foetidus, two different approaches were proposed. In the first case, the enzyme activity adsorbed on residual solids after extended hydrolysis was used for hydrolysis of the newly added substrate. The initial mixing of fresh and hydrolyzed substrates was sufficient for the adsorbed enzyme redistribution and conversion of the new substrate portion, and permanent mechanical stirring was not required. Feeding of two additional portions of the exploded hardwood adjusted to pH 4 with dry caustic into the reactor with simultaneous replacement of accumulated sugars with fresh buffer (pH 4.5) resulted, on average, in a 90% conversion of cellulose at the final enzyme loading 8 IFPU per g ODM substrate, an average sugar concentration of 12%, and a glucose/xylose ratio of 5:1. In the second approach, weakly adsorbed cellulase fractions were used for static high-solids hydrolysis followed by their ultrafiltration recovery from the resultant sugar syrup. In contrast to the initial cellulase mixture whose residual activity in a syrup did not exceed 5-10% at the end of hydrolysis (48 h), up to 60% of weakly adsorbed enzyme fraction could be separated from sugar syrups by ultrafiltration and then reused. Weakly adsorbed enzymes displayed a hydrolysis efficiency of not less than 80% per IFPU enzyme consumed in extended hydrolysis of pretreated willow as compared to the original enzyme mixture. An electrophoretic study of the weakly adsorbed enzyme fraction identified T. reesei cellobiohydrolase II as the predominant component, whereas clear domination of T. reesei cellobiohydrolase I was found by electrophoresis of proteins tightly bound to hydrolysis residual solids.


Assuntos
Celulase/metabolismo , Árvores/metabolismo , Aspergillus/enzimologia , Ativação Enzimática , Hidrólise , Vapor , Trichoderma/enzimologia
12.
Prikl Biokhim Mikrobiol ; 36(1): 13-6, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10752077

RESUMO

Six strains containing site-specific endonucleases II were selected from a collection of 45 ice-nucleating bacterial strains isolated from rhizosphere of plants growing in various geographical regions. Endonucleases Pfl211I, Psp8I, and Psp23I were isolated and purified from two Pseudomonas sp. strains and a Pseudomonas fluorescens strain. Restriction endonucleases Pfl21I and Psp23I were shown to recognize and cleave the DNA nucleotide sequence 5'-CTGCA decrease G-3'. Endonuclease Psp8I recognized and cleaved the DNA nucleotide sequence 5'-G decrease GATCC-3'. These endonucleases were found to be true isoschizomers of PstI and BamHI, respectively.


Assuntos
Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Pseudomonas/enzimologia , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/isolamento & purificação , Gelo , Especificidade por Substrato
13.
Prikl Biokhim Mikrobiol ; 36(2): 122-30, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10779997

RESUMO

A laboratory reactor equipped with a screw press was used for hydrolysis of steam-SO2 exploded willow Salix caprea by a composition of Trichoderma reesei and Aspergillus foetidus enzyme preparations at high substrate concentrations. Optimal conditions providing the maximal volume of hydrolysis syrup with maximal sugar concentrations were determined. Two different hydrolysis procedures were developed in order to exclude initial washing of steam-pretreated plant raw material by large volumes of water, which is necessary to eliminate the inhibitory effect of explosion by-products on enzymatic hydrolysis. The first procedure included a one-hour-long enzymatic prehydrolysis of the substrate, then separation of sugar syrup containing 40-60 g/l of glucose, 20-25 g/l of xylose, and up to 10% of disaccharides, as well as up to 35% of the initial enzymatic activity, then addition of a diluted acetate buffer (pH 4.5), and subsequent hydrolysis of the substrate by the adsorbed enzymes leading to the final accumulation of up to 140 g/l glucose and up to 15 g/l xylose. In the second scenario, the exploded willow was initially adjusted by alkali to pH 4.5 and then hydrolyzed directly by added enzymes for 24 hours. This procedure resulted in a nearly total polysaccharide hydrolysis and accumulation of up to 170 g/l glucose and 20 g/l xylose. The reasons of inhibition of enzymatic hydrolysis are discussed.


Assuntos
Enzimas/metabolismo , Aspergillus/enzimologia , Celulose/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Hidrólise , Especificidade por Substrato , Trichoderma/enzimologia
14.
Biotechnol Bioeng ; 67(6): 737-47, 2000 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-10699855

RESUMO

A new approach to preparative organic synthesis in aqueous-organic systems is suggested. It is based on the idea that the enzymatic process is carried out in a biphasic system "water-water-immiscible organic solvent." Thereby the enzyme is localized in the aqueous phase-this eliminates the traditional problem of stabilizing the enzymes against inactivation by a nonaqueous solvent. Hence, in contrast to the commonly used combinations "water-water-miscible organic solvent," in the suggested system the content of water may be infinitely low. This allows one to dramatically shift the equilibrium of the reactions forming water as a reaction product (synthesis of esters and amides, polymerization of amino acids, sugars and nucleotides, dehydration reactions, etc.) toward the products. The fact that the system consists of two phases provides another very important sources for an equilibrium shift, i.e., free energies of the transfer of a reagent from one phase to the other. Equations are derived describing the dependence of the equilibrium constant in a biphasic system on the ratio of the volumes of the aqueous and nonaqueous phases and the partition coefficients of the reagents between the phases. The approach has been experimentally verified with the synthesis of N-acetyl-L-tryptophan ethyl ester from the respective alcohol and acid. Porous glass was impregnated with aqueous buffer solution of chymotrypsin and suspended in chloroform containing N-acetyl-L-tryptophan and ethanol. In water (no organic phase) the yield of the ester is about 0.01%, whereas in this biphasic system it is practically 100%. The idea is applicable to a great number of preparative enzymatic reactions.


Assuntos
Enzimas/história , Animais , Bovinos , Enzimas/síntese química , História do Século XX , Solventes
16.
Am J Physiol ; 277(2): G409-23, 1999 08.
Artigo em Inglês | MEDLINE | ID: mdl-10444456

RESUMO

To reveal the unique intrinsic properties of interstitial cells of Cajal (ICC), morphological and electrophysiological characteristics of isolated ICC from the adult mouse small intestine were investigated and compared with those of smooth muscle cells. All typical ultrastructural features of in situ ICC were evident in isolated ICC throughout the isolation procedure and short-term culture. With the use of the nystatin perforated patch-clamp technique, ICC demonstrated spontaneous voltage oscillations that were not abolished by hyperpolarization nor by L-type calcium channel blockers. This rhythmic activity occurred at room temperature at a frequency of 13.9 +/- 11.2 cycles/min, with an amplitude of 13.4 +/- 11.2 mV at membrane potentials from -20 to -70 mV. Smooth muscle cells from the same culture only generated voltage-sensitive action potentials above the threshold potential of -35 mV. Hyperpolarization as well as the addition of L-type calcium channel blockers abolished the action potentials. In whole cell voltage-clamp recordings from ICC, a large noninactivating outward current was observed to be activated (5% threshold) at -49.6 mV with a half-activation voltage of -18.7 mV and slope factor of 9.9 mV. In contrast, in smooth muscle cells, smaller outward currents with distinctive transient outward currents were present. In conclusion, the generation of L-type calcium channel blocker-insensitive slow waves in membrane potential is a unique intrinsic property of ICC.


Assuntos
Intestino Delgado/citologia , Intestino Delgado/fisiologia , Animais , Colforsina/farmacologia , Eletrofisiologia , Inibidores Enzimáticos/farmacologia , Feminino , Motilidade Gastrointestinal , Indóis/farmacologia , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/ultraestrutura , Potenciais da Membrana , Camundongos , Microscopia Eletrônica , Músculo Liso/citologia , Músculo Liso/fisiologia , Oscilometria
17.
Neurogastroenterol Motil ; 11(3): 179-92, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10354343

RESUMO

A Trichinella spiralis infection produces an acute inflammatory reaction and tissue damage in the mucosa, and, in addition, functional changes occur in the external muscle layers. The aim of the present study was to characterize structural changes in the musculature that occur during early infection, and to identify relationships between immune cells and muscle cells, as part of an ongoing investigation into the immune modulation of motor function in the gut. Rats were infected with T. spiralis larvae and the gut fixed at 12 h, 24 h, 48 h and 6 days post-infection for electron microscopy of the longitudinal muscle. Macrophages and lymphocytes penetrated the longitudinal musculature 12-24 h post-infection. Distinct contacts were observed between specific cell types; cellular protrusions from macrophages or lymphocytes made close apposition contacts with smooth muscle cells. Resident macrophages in the subserosal space, fibroblast-like cells as well as smooth muscle cells showed marked activation during inflammation. Fibroblast-like cells were frequently seen intercalated between lymphocytes and smooth muscle cells, hence they may mediate communication between immune cells and the musculature.


Assuntos
Sistema Imunitário/patologia , Músculo Liso/imunologia , Trichinella spiralis , Triquinelose/imunologia , Animais , Linfócitos/imunologia , Macrófagos/imunologia , Masculino , Microscopia Eletrônica , Junção Neuromuscular/imunologia , Ratos , Ratos Sprague-Dawley
18.
Am J Surg Pathol ; 23(4): 377-89, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10199467

RESUMO

Interstitial cells of Cajal (ICC) are implicated in the regulation of gut peristalsis and are immunostained by antibodies against Kit (CD117), a tyrosine kinase receptor. Most gastrointestinal mesenchymal tumors (GIMTs) are of uncertain histogenesis, although many are CD34-positive. CD34 was found to colocalize with vimentin (Vim) and the Kit-positive networks of cells within and around neural plexi, indicating that ICC can be Vim- and CD34-positive. ICCs appear to be the only Kit+CD34+Vim+ cell in the gut. Formalin-fixed, paraffin-embedded tissues from 43 GIMTs were immunostained for Kit, CD34, Vim, PGP 9.5 (PGP, a neural marker), muscle-specific actin (MSA), and other markers including desmin (Des). Eight tumors were myoid (MSA+Des+Vim-Kit-CD34-), and one was a schwannoma (PGP+S100+Vim+Kit-CD34-), but 34 tumors were of uncertain histogenesis (gastrointestinal stromal tumors, GIST), exhibiting neither a complete myoid nor a schwannian immunophenotype. All 34 were Vim+, and 33/34 were either Kit (n = 30) or CD34 (n = 23) immunoreactive. Of these 34 GIST, 24 were negative for all myoid and neural markers, 6 were PGP+S100-, and 4 were MSA+Des-. The Kit+CD34+Vim+ immunophenotype of GIST suggests that they originate from, or have differentiated into, ICC-like cells; the term ICC tumor (ICCT) is suggested. Kit is a more sensitive marker than CD34 for ICCT, but both are required in tumor identification. All clinically malignant GISTs were pathologically malignant (size, mitoses) but also showed loss of either CD34 or Kit. "Blind" examination of electron micrographs in 10 tumors showed them to be heterogeneous. Some had features seen in normal ICC, but cells could not be positively identified as being adult ICC. GIMT may therefore be classifiable into those with pure myoid, schwannian (or neural) differentiation, but the majority are of ICC origin or show ICC differentiation immunophenotypically (ICCT).


Assuntos
Sistema Digestório/citologia , Neoplasias Gastrointestinais/patologia , Neoplasias de Tecido Conjuntivo/patologia , Lesões Pré-Cancerosas/patologia , Células Estromais/patologia , Biomarcadores Tumorais/análise , Feminino , Neoplasias Gastrointestinais/química , Humanos , Técnicas Imunoenzimáticas , Leiomiossarcoma/química , Leiomiossarcoma/patologia , Leiomiossarcoma/secundário , Plexo Mientérico/química , Plexo Mientérico/patologia , Neoplasias de Tecido Conjuntivo/química , Neurilemoma/química , Neurilemoma/patologia , Lesões Pré-Cancerosas/química , Neoplasias de Tecidos Moles/química , Neoplasias de Tecidos Moles/patologia , Células Estromais/química , Neoplasias Uterinas/química , Neoplasias Uterinas/patologia
20.
Cell Tissue Res ; 294(1): 69-79, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9724457

RESUMO

The network of interstitial cells of Cajal associated with Auerbach's (myenteric) plexus in the canine colon was investigated to determine its role in facilitating communication between circular and longitudinal muscle layers. Electrical coupling between the muscle layers was demonstrated by propagating extracellularly evoked electrotonic pulses from circular muscle cells to nearby longitudinal muscle cells. The likelihood of cytoplasmic continuity across Auerbach's plexus was further demonstrated by the ability of neurobiotin to spread between the interstitial cells and the circular and longitudinal muscle cells. Importantly, direct neurobiotin spread between circular and longitudinal muscle cells was not observed even when they were in close proximity as determined by confocal microscopy. When neurobiotin did spread across the two muscle layers, the intervening interstitial cells were always neurobiotin-positive. In regions where circular and longitudinal muscle cells approach each other closely, electron microscopy revealed the presence of close appositions between interstitial cells and smooth muscle cells. Gap junctions between interstitial cells and smooth muscle cells of both layers, as judged by electron microscopy, were extremely rare. Neither gap junctions nor close appositions were observed between longitudinal and circular muscle cells. The special arrangement for electrotonic coupling across Auerbach's plexus through interstitial cells of Cajal suggests controlled coupling between the two muscle layers, explaining the preservation of their distinct electrical activities.


Assuntos
Colo/citologia , Colo/inervação , Músculo Liso/citologia , Músculo Liso/inervação , Plexo Mientérico/citologia , Animais , Biotina/análogos & derivados , Biotina/farmacocinética , Comunicação Celular , Colo/fisiologia , Cães , Eletrofisiologia , Feminino , Motilidade Gastrointestinal/fisiologia , Masculino , Microscopia Eletrônica , Músculo Liso/fisiologia , Plexo Mientérico/fisiologia
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