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1.
Int J Oral Maxillofac Surg ; 53(4): 352-353, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37858383
2.
Int J Oral Maxillofac Surg ; 52(8): 854-859, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36669931

RESUMO

Velopharyngeal structure augmentation with the injection of autologous fat tissue into the nasal mucosa of the soft palate has been reported previously. However, as the injection points in the velopharyngeal space cannot be observed directly, these injections may be difficult to perform accurately. This report describes a new endoscope-assisted approach in which the materials for velopharyngeal structure augmentation are administered while observing the injection points directly, also enabling adjustment of the amount of material injected. A case series of five patients aged 8-16 years who underwent endoscopic soft palate augmentation under general anaesthesia is reported. Autologous fat tissue was injected into the nasal mucosa of the soft palate using a needle-type device of an endoscope, and the effects of the treatment were evaluated. The injections were performed successfully, and the velopharyngeal function was improved. This new technique of endoscopy-assisted augmentation was useful for the treatment of velopharyngeal insufficiency.


Assuntos
Tecido Adiposo , Endoscopia , Insuficiência Velofaríngea , Humanos , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/cirurgia , Palato Mole/anormalidades , Palato Mole/transplante , Insuficiência Velofaríngea/cirurgia , Tecido Adiposo/transplante , Masculino , Feminino , Criança , Adolescente
3.
Epidemiol Infect ; 147: e148, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30869058

RESUMO

To characterise the dissemination patterns of uropathogenic Escherichia coli (UPEC) in a community, we conducted a study utilising molecular and fundamental descriptive epidemiology. The subjects, consisted of women having community-acquired acute urinary tract infection (UTI), were enrolled in the study from 2011 to 2012. UPEC isolates were subjected to antibacterial-susceptibility testing, O serogrouping, phylotyping, multilocus-sequence typing with phylogenetic-tree analysis and pulsed-field-gel electrophoresis (PFGE). From the 209 unique positive urinary samples 166 UPEC were isolated, of which 129 were fully susceptible to the tested antibiotics. Of the 53 sequence types (STs), the four most prevalent STs (ST95, ST131, ST73 and ST357) accounted for 60% of all UPEC strains. Antimicrobial resistance was less frequently observed for ST95 and ST73 than for the others. A majority of rare STs and a few common STs constituted the diversity pattern within the population structure, which was composed of the two phylogenetically distinct clades. Eleven genetically closely related groups were determined by PFGE, which accounted for 42 of the 166 UPEC isolates, without overt geo-temporal clustering. Our results indicate that a few major lineages of UPEC, selected by unidentified factors, are disseminated in this community and contribute to a large fraction of acute UTIs.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Infecções por Escherichia coli/epidemiologia , Genótipo , Infecções Urinárias/epidemiologia , Escherichia coli Uropatogênica/isolamento & purificação , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/transmissão , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/transmissão , Feminino , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem Molecular , Sorotipagem , Infecções Urinárias/microbiologia , Infecções Urinárias/transmissão , Escherichia coli Uropatogênica/classificação , Escherichia coli Uropatogênica/efeitos dos fármacos , Escherichia coli Uropatogênica/genética
4.
Cytopathology ; 29(3): 262-266, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29578263

RESUMO

BACKGROUND: Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens. METHODS: Aspiration samples (n = 41) were smeared on glass slides and used for FISH. RESULTS: Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound-guided FNA samples from the pancreas (n = 18). CONCLUSIONS: The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients.


Assuntos
Telômero/genética , Ascite/genética , Ascite/patologia , Instabilidade Cromossômica/genética , Fluorescência , Humanos , Hibridização in Situ Fluorescente/métodos , Pâncreas/patologia , Derrame Pleural/genética , Derrame Pleural/patologia
5.
Bull Entomol Res ; 108(4): 471-478, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29061206

RESUMO

The brown planthopper Nilaparvata lugens Stål (BPH) can be found year-round in tropical region and causes severe damage to rice. Although there has been documented BPH damage to rice crops in the past decade in Cambodia, the extent of this epidemic is poorly understood. Here, we examined the time variation of BPH population in the abundance of morphotypes in 13 main rice-producing provinces (86 sites) by aspirator method and in the Takeo Province (five sites) by yellow sticky trap method. At least three generations were observed during the 3-month collection period in the rainy growing season. Regarding the occurrence of BPH morphotypes, in July the macropterous adults were restricted to south Cambodia and in August all morphotypes, adults (macropterous and brachypterous) and nymphs, appeared in all sampling sites. To explain the difference of regional distribution, the genetic differentiation was analyzed in south and northwest Cambodia (three sites) by using single nucleotide polymorphisms (SNP) analysis via genotyping-by-sequencing (GBS) using next-generation sequencing. The 2455 SNPs obtained by GBS clarified the three sub-populations and they corresponded to the expected dissemination patterns. These results provide a clue to understand the differentiation and epidemic of BPH in Cambodia.


Assuntos
Hemípteros/genética , Animais , Camboja , Demografia , Feminino , Genética Populacional , Técnicas de Genotipagem , Hemípteros/crescimento & desenvolvimento , Ninfa , Polimorfismo de Nucleotídeo Único/genética , Estações do Ano , Análise de Sequência de DNA
7.
Bone ; 46(6): 1620-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20230926

RESUMO

The aim was to evaluate a new ultrasound device in a young adult population and to assess its reproducibility via comparison to DXA measurements and geometrical measurements from high-resolution radiographs. Ninety-three subjects aged between 20 and 51 years were recruited and divided into four groups according to their gender and physical activity status: 22 male athletes, 19 male controls, 21 female athletes, and 31 female controls. Ultrasonic measurements were assessed by the prototype LD-100 (Oyo Electric Co., Kyoto, Japan) on the dominant distal radius. Attenuation in the radius (dB), cortical bone thickness (mm), radius thickness (mm), mass density of cancellous bone (mg/cm(3)), and elasticity (GPa) of cancellous bone were obtained. BMD was measured by DXA at the dominant distal radius. Radius images were obtained with a direct high-resolution digital X-ray device (BMA, D(3)A Medical Systems), and radius and cortical thicknesses were estimated using a specific software (ImageJ, Bethesda, USA), in an area site-matched with LD-100. There was a significant positive correlation between site-matched BMD measurement and LD-100 parameters (p<0.004), X-ray radius thickness, and LD-100 parameters except elasticity (p<0.05, r>0.32), X-ray cortical thickness and LD-100 attenuation and cortical thickness (p<0.01). A significantly higher attenuation, cortical and radius thicknesses were found in athletes compared to controls (p<0.05). The radius thickness measured on radiographs was significantly higher in athletes versus controls in both sexes, and cortical thickness was significantly higher in male athletes versus controls. These data suggest a positive influence of physical activity on bone cortical measurements. This study also confirmed the particular interest of bone assessment by ultrasound.


Assuntos
Atividade Motora/fisiologia , Rádio (Anatomia)/diagnóstico por imagem , Adulto , Estatura , Peso Corporal , Densidade Óssea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rádio (Anatomia)/metabolismo , Tomografia Computadorizada por Raios X , Ultrassonografia , Adulto Jovem
8.
J Phys Condens Matter ; 21(48): 486001, 2009 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-21832533

RESUMO

We have studied the effect of pressure on the anomalous lattice striction, both in the ab-plane and along the c-axis, of (La,Pr)(1.2)Sr(1.8)Mn(2)O(7) single crystals over the temperature region where the paramagnetic insulator to ferromagnetic metal transition takes place. We have examined the temperature dependence of the resistivity and the magnetization under applied pressure. The chemical pressure effect due to Pr-substitution at the La site suppresses the transition temperature of the parent crystal, while the application of external pressure on Pr-substituted crystals enhances the double exchange driven metallic state, resulting in a stable rise of T(c).

9.
Artigo em Inglês | MEDLINE | ID: mdl-18986937

RESUMO

Ultrasonic waves in cancellous bone change dramatically depending on its structural complexity. One good example is the separation of an ultrasonic longitudinal wave into fast and slow waves during propagation. In this study, we examined fast wave propagation in cancellous bone obtained from the head of the bovine femur, taking the bone structure into consideration. We investigated the wave propagation perpendicular to the bone axis and found the two-wave phenomenon. By rotating the cylindrical cancellous bone specimen, changes in the fast wave speed due to the rotation angle then were observed. In addition to the ultrasonic evaluation, the structural anisotropy of each specimen was measured by X-ray micro-computed tomography (CT). From the CT images, we obtained the mean intercept length (MIL), degree of anisotropy (DA), and angle of insonification relative to the trabecular orientation. The ultrasonic and CT results showed that the fast wave speed was dependent on the structural anisotropy, especially on the trabecular orientation and length. The fast wave speeds always were higher for propagation parallel to the trabecular orientation. In addition, there was a strong correlation between the DA and the ratio between maximum and minimum speeds (V(max)/V(min)) (R(2) = 0.63).


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Fêmur/diagnóstico por imagem , Fêmur/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Modelos Biológicos , Animais , Anisotropia , Bovinos , Simulação por Computador , Módulo de Elasticidade , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade , Estresse Mecânico
10.
Phys Rev Lett ; 98(26): 267204, 2007 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-17678125

RESUMO

We report a steplike lattice transformation of single crystalline (La0.4Pr0.6)1.2Sr1.8Mn2O7 bilayered manganite accompanied by both magnetization and magnetoresistive jumps, and examine the ultrasharp nature of the field-induced first-order transition from a paramagnetic insulator to a ferromagnetic metal phase accompanied by a huge decrease in resistance. Our findings support that the abrupt magnetostriction is closely related to an orbital frustration existing in the inhomogeneous paramagnetic insulating phase rather than a martensitic scenario between competing two phases.

12.
Kyobu Geka ; 59(4): 340-3, 2006 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-16613155

RESUMO

A 19-year-old man was punched on the back, and anterior chest pain appeared about 3 hours after injury. The patient was consulted a physician complaining of anterior chest pain. On chest X-ray, mediastinal emphysema was suspected, and transferred to our hospital. Chest computed tomography (CT) revealed mediastinal emphysema. On esophageal radiography and bronchofiberscopy, no abnormal findings were detected. Conservative therapy was conducted, and symptoms had gradually improved. On the 8th hospital day, mediastinal emphysema was improved on chest CT. The patient was discharged on the 10th hospital day. The most frequent cause of mediastinal emphysema after trauma is traffic or downfall accident, and no report on this condition after the punch on the back was found.


Assuntos
Lesões nas Costas/complicações , Enfisema Mediastínico/etiologia , Ferimentos não Penetrantes/complicações , Adulto , Dor no Peito/etiologia , Humanos , Masculino , Enfisema Mediastínico/diagnóstico por imagem , Enfisema Mediastínico/terapia , Tomografia Computadorizada por Raios X
13.
Neuroscience ; 138(1): 37-46, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16343782

RESUMO

Both serotonin and noradrenaline affect synapse formation and maintenance in the CNS. Although we previously demonstrated that serotonin regulates synaptic density via activation of serotonin(2A) receptor, it was still unclear which receptor subtype mediates the function of noradrenaline. In the present study we tried to identify the noradrenaline receptor (adrenoceptor) subtype, which could regulate the density of synapses in the rat visual cortex. Selective antagonists and/or agonists of adrenoceptor subtypes were administered to six weeks old rats. Changes in the density of axodendritic synapses were quantitatively examined in lamina I, where noradrenaline rather than serotonin is known to regulate the density of synapses. The alpha1 adrenoceptor antagonists (prazosin and 2-{[b-(4-hydroxyphenyl)ethyl]aminomethyl}-1-tetralone) decreased the number of synapses in a dose-dependent manner. In contrast, administrations of the alpha1-agonist (methoxamine) increased the density of synapses. The beta1 adrenoceptor antagonist (atenolol) had no effect on the density of synapses. The alpha2-antagonist (rauwolscine) increased synaptic density, whereas the beta2-antagonist (ICI-118,551) decreased synaptic density. Simultaneous treatments with the alpha1-antagonist and alpha1-agonist caused the alpha1-agonist to competitively block the effect of the alpha1-antagonist and recover the density of synapses to the control values. In addition, the alpha1-antagonist/agonist appeared to show a reverse effect on the changes in synaptic density following alpha2- or beta2-antagonist treatment by acting via the alpha1 receptor. Moreover, decreased synaptic density when a selective noradrenergic neurotoxin (N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine) was counterbalanced by the alpha1-agonist. These data suggest that noradrenaline regulates the density of synapses in the rat visual cortex primarily via the alpha1 receptor subtype. Both serotonin(2A) and alpha1 receptors are known to couple with phospholipase C, which has been shown to increase intracellular calcium. It may help us to understand the underlying mechanisms for synaptic plasticity in the CNS.


Assuntos
Receptores Adrenérgicos/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Córtex Visual/efeitos dos fármacos , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Masculino , Microscopia Eletrônica , Plasticidade Neuronal/efeitos dos fármacos , Norepinefrina/fisiologia , Ratos , Ratos Wistar , Receptor 5-HT2A de Serotonina/efeitos dos fármacos , Receptores Adrenérgicos alfa 1/efeitos dos fármacos , Receptores Adrenérgicos alfa 1/fisiologia , Serotonina/fisiologia , Sinapses/ultraestrutura , Fixação de Tecidos , Córtex Visual/ultraestrutura
14.
Calcif Tissue Int ; 76(6): 433-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15895284

RESUMO

It is known that the excessive generation of reactive oxygen species (ROS) is a significant factor in tissue injury observed in many disease states. To determine whether extreme levels of mechanical stress applied to osteoblasts enhances ROS synthesis, we loaded cyclic tensile stretch on osteoblast-like HT-3 cells. Cyclic tensile stretch loaded on these cells clearly enhanced ROS synthesis in a time- and magnitude-dependent fashion. Cyclic tensile stretch also enhanced superoxide dismutase (SOD) activity. The disruption of microfilaments with cytochalasin D abolished the stress-induced ROS synthesis. Rotenone, an inhibitor of the mitochondrial electron transport chain, enhanced stress-induced ROS synthesis. These data suggest that actin filament and mitochondria are involved in this action.


Assuntos
Osteoblastos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Mecânico , Actinas/metabolismo , Animais , Linhagem Celular Tumoral , Mitocôndrias/metabolismo , RNA Mensageiro/análise , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Superóxido Dismutase/biossíntese
15.
Dig Liver Dis ; 37(5): 363-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15843087

RESUMO

BACKGROUND AND AIMS: The origin of a long common channel in pancreaticobiliary maljunction was suggested to be the ventral pancreatic duct. Pathogenesis of long common channels was investigated by anatomically analysing the arrangement of pancreatic ducts in pancreaticobiliary maljunction. MATERIALS AND METHODS: Cholangiopancreatography was performed for 66 cases of pancreaticobiliary maljunction and 200 controls. The accessory pancreatic duct was classified according to course and shape. In cases with long- or short-type accessory pancreatic duct, lengths of the main pancreatic duct from orifice to first inferior branch and junction with the accessory pancreatic duct, and the common channel were measured. RESULTS: Lengths of the main pancreatic duct from orifice to first inferior branch or junction with the accessory pancreatic duct were significantly longer in cases of pancreaticobiliary maljunction cases with the long- or short-type accessory pancreatic duct than in controls (p<0.01). Lengths of the main pancreatic duct from first inferior branch to junction with the accessory pancreatic duct were roughly equivalent in pancreaticobiliary maljunction and controls. CONCLUSIONS: Long common channels in pancreaticobiliary maljunction might be formed embryologically with adhesion of the right ventral pancreatic duct and the terminal portion of the bile duct.


Assuntos
Ductos Biliares Extra-Hepáticos/anormalidades , Ductos Pancreáticos/anormalidades , Ductos Biliares Extra-Hepáticos/diagnóstico por imagem , Ductos Biliares Extra-Hepáticos/patologia , Colangiopancreatografia Retrógrada Endoscópica , Dilatação Patológica , Humanos , Ductos Pancreáticos/diagnóstico por imagem , Estudos Retrospectivos
16.
Kyobu Geka ; 58(4): 295-9, 2005 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-15828249

RESUMO

Papillary muscle rupture is a rare but severe complication of acute myocardial infarction. Two cases successfully underwent mitral valve replacement and concomitant coronary artery bypass grafting (CABG) for acute myocardial infarction with the anterior papillary muscle rupture in cardiogenic shock. Each of them needed preoperative massive inotropic infusion, respiratory support and intraaortic balloon pumping assist. The first case was a 76-year-old female. Double vessel disease (seg 7 : 90%, seg 11 : 100%) was revealed by coronary angiography and rupture of the papillary muscle was confirmed by transesophageal echocardiography. The second case was a 69-year-old female. Double vessel disease (seg 2 : 90%, seg 11 : 100%) was revealed and severe mitral regurgitation due to prolapse of the anterior leaflet was confirmed by transthoracic echocardiography. To assess the diagnosis of postinfarction papillary muscle rupture, transthoracic and/or transesophageal echocardiography is mandatory. Coronary angiography is also desirable because concomitant myocardial revascularization may improve the prognosis.


Assuntos
Ruptura Cardíaca Pós-Infarto/cirurgia , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral/cirurgia , Músculos Papilares/cirurgia , Idoso , Procedimentos Cirúrgicos Cardíacos/métodos , Ponte de Artéria Coronária , Feminino , Humanos , Valva Mitral/cirurgia
17.
J Med Screen ; 11(3): 141-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15333273

RESUMO

AIM: To assess the validity of the measurement of pepsinogen I and II as a screening test for gastric cancer and pre-malignant lesions, namely low-grade dysplasia, both in the general population and in selected groups of patients. METHODS: A meta-analysis of sensitivity and specificity results from individual papers on the use of the pepsinogen test. An intrinsic cut-off effect was assumed and a random effect model was used for pooling. RESULTS: Forty-two data sets were included: 27 (64%) population-based screening studies (n=296,553) and 15 (36%) sets of selected individuals (n=4385). Homogenous sensitivity and diagnostic odds ratio (DOR) estimates were found in studies using both pepsinogen I levels and pepsinogen I/II ratio calculations. Pooled pairs of sensitivity and false positive rates (FPr) for pepsinogen I < or = 70; pepsinogen I/II ratio < or = 3, pepsinogen I < or =50; pepsinogen I/II ratio < or = 3, and pepsinogen I < or = 30; pepsinogen I/II ratio < or = 2, were sensitivity 77%/FPr 27%, sensitivity 68%/FPr 31%, and sensitivity 52%/FPr 84%, respectively. Positive predictive values (PPV) varied between 0.77% and 1.25%, and negative predictive values (NPV) varied between 99.08% and 99.90%. In selected groups, pooling was only possible when considering pepsinogen I < or = 70; pepsinogen I/II ratio < or = 3: giving sensitivity 57%, specificity 80%, PPV 15% and NPV 83%. As for the diagnosis of dysplasia, studies considering pepsinogen I <50; pepsinogen I/II ratio <3 obtained sensitivity 65% and specificity ranging from 74%-85%, both with NPV >95%. CONCLUSION: Pepsinogen test definition should include pepsinogen I/II ratio as consistency was obtained, both in population based studies and in selected groups for those studies that used pepsinogen I serum levels together with pepsinogen I/II ratio for screening for gastric cancer in high-incidence regions other than Japan. Further studies of this test in the management of high-risk patients seem to be worthwhile.


Assuntos
Gastrite Atrófica/diagnóstico , Pepsinogênio A/sangue , Pepsinogênio C/sangue , Neoplasias Gástricas/diagnóstico , Reações Falso-Positivas , Humanos , Programas de Rastreamento/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Inflamm Res ; 53(6): 239-44, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15167970

RESUMO

OBJECTIVE: Mechanical stress is an essential factor in the pathogenesis of osteoarthrosis. We sought to determine whether the strain-mediated alteration in proteoglycan (PG) synthesis was modulated by nitric oxide (NO) synthesis. METHODS: Cyclic tensile strain was applied to bovine articular chondrocytes. PG and NO synthesis were determined by [35S] sulfate incorporation and chemiluminescence analysis, respectively. To determine the expression of inducible NO synthase (iNOS), quantitative RT-PCR was used. RESULTS: Enhanced PG and NO synthesis were evident when cyclic tensile strain was applied to chondrocytes seeded on fibronectin-coated plates. When NO production was inhibited, PG synthesis was further enhanced. CONCLUSIONS: Cyclic tensile strain loaded on the chondrocytes enhanced NO synthesis and this enhanced NO inhibited PG synthesis.


Assuntos
Condrócitos/metabolismo , Fibronectinas/metabolismo , Óxido Nítrico/biossíntese , Proteoglicanas/biossíntese , Animais , Cartilagem/metabolismo , Bovinos , Adesão Celular , DNA/metabolismo , Primers do DNA/química , Relação Dose-Resposta a Droga , Sulfato de Queratano/metabolismo , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo II , Oligonucleotídeos/química , Osteoartrite/metabolismo , Proteoglicanas/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estresse Mecânico , Sulfatos/metabolismo , Fatores de Tempo
19.
Neuroscience ; 122(3): 627-35, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14622906

RESUMO

Biogenic amines have a trophic-like role for the formation and the maintenance of synapses in the CNS. We examined the changes in the number of synaptic profiles in the developing and adult rat visual cortex following selective depletion of noradrenaline and/or serotonin. By the drug-induced decreases in levels of noradrenaline or serotonin between 1 and 2 weeks after birth, the number of synaptic profiles was decreased by 29-55% compared with that of control animals. The magnitude of reduction in the number of synaptic profiles was virtually the same following simultaneous depletion of both noradrenaline and serotonin compared with the depletion of noradrenaline or serotonin alone. Later in the developmental period, the function of noradrenaline and serotonin in facilitating synapse formation and maintenance became less prominent than that in younger animals. In the control animals, the number of axosomatic synapses was the highest at around 2 weeks after birth, and decreased with development. The number of axodendritic synapses was the highest between 2 and 7 weeks after birth, and decreased to 50% at 11 weeks after birth. These data demonstrate that synapses in the rat visual cortex are overproduced during the early developmental period. We suggest that both serotonin and noradrenaline are necessary for synapse formation during the early stages of development of the rat visual cortex.


Assuntos
Norepinefrina/metabolismo , Serotonina/metabolismo , Sinapses/metabolismo , Córtex Visual/metabolismo , Envelhecimento , Animais , Animais Recém-Nascidos , Benzilaminas/toxicidade , Contagem de Células , Interações Medicamentosas , Fenclonina/toxicidade , Masculino , Microscopia Eletrônica , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Inibidores da Captação de Neurotransmissores/toxicidade , Distribuição Aleatória , Ratos , Ratos Wistar , Antagonistas da Serotonina/toxicidade , Sinapses/efeitos dos fármacos , Sinapses/ultraestrutura , Córtex Visual/citologia , Córtex Visual/efeitos dos fármacos
20.
Arthritis Rheum ; 48(11): 3151-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14613277

RESUMO

OBJECTIVE: We have previously demonstrated that reactive oxygen species (ROS) are involved in cartilage degradation. Decreased size of hyaluronan (HA), the major macromolecule in synovial fluid, to which it imparts viscosity, is reported in patients with arthritis. The purpose of this study was to determine the alteration in the molecular weight range of HA as a result of mechanical deformation loaded on the chondrocytes, as well as the involvement of ROS in this action. METHODS: ROS were generated via the oxidation of hypoxanthine by xanthine oxidase. Cyclic tensile stretch was loaded using a vacuum-operated instrument. Levels of HA were measured using a sandwich enzyme-binding assay. Superoxide dismutase (SOD) activity and ROS were measured using water-soluble tetrazolium and a chemiluminescent probe, respectively. RESULTS: ROS depolymerized HA molecules. Cyclic tensile stretch depolymerized HA and induced ROS. SOD inhibited not only ROS induction but also HA depolymerization caused by the mechanical stress. CONCLUSION: ROS play an important role in mechanical stress-induced HA depolymerization.


Assuntos
Condrócitos/metabolismo , Ácido Hialurônico/metabolismo , Polímeros/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Bovinos , Condrócitos/efeitos dos fármacos , Ácido Hialurônico/química , Ácido Hialurônico/genética , Hipoxantina/metabolismo , Peso Molecular , Polímeros/química , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estresse Mecânico , Superóxido Dismutase , Resistência à Tração/fisiologia , Xantina Oxidase/metabolismo
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