RESUMEN
Correlated firings among neurons have been extensively investigated; however, previous studies on retinal ganglion cell (RGC) population activities were mainly based on analyzing the correlated activities between the entire spike trains. In the present study, the correlation properties were explored based on burst-like activities and solitary spikes separately. The results indicate that: (1) burst-like activities were more correlated with other neurons' activities; (2) burst-like spikes correlated with their neighboring neurons represented a smaller receptive field than that of correlated solitary spikes. These results suggest that correlated burst-like spikes should be more efficient in signal transmission, and could encode more detailed spatial information.
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Animales , Potenciales de Acción , Simulación por Computador , Oscuridad , Electrofisiología , Técnicas In Vitro , Luz , Técnicas de Placa-Clamp , Sumación de Potenciales Postsinápticos , Rana catesbeiana , Fisiología , Cirugía General , Retina , Fisiología , Células Ganglionares de la Retina , Fisiología , Neuronas Retinianas , Fisiología , Transducción de SeñalRESUMEN
<p><b>OBJECTIVE</b>To study the effect of angiotensin II on phosphoinositide-3 kinase/Akt cascade in cultured fibroblasts derived from patients with hypertrophic scars.</p><p><b>METHODS</b>The expression of AT1 and AT2 receptor was detected by immunofluorescence staining. Cultured human skin fibroblasts were treated with Ang II (10(-9) - 10(-7) mol/L), with or without an AT1 receptor blocker, valsartan or an AT2 receptor antagonist, PD123319. The phosphorylation of Akt was detected by western blotting, and PI3K activity was measured by Assay of PI3-K activity.</p><p><b>RESULTS</b>Immunofluorescence staining showed that cultured fibroblasts derived from hypertrophic scars expressed both AT1 and AT2 receptors. Ang II increased Akt phosphorylation and PI3K activity in cultured hypertrophic scar fibroblasts in a dose- and time-dependent manner. Additionally, Ang II-induced Akt phosphorylation was blocked by wortmannin, a PI3-K inhibitor. This Ang II-activated PI3-K/Akt cascade was significantly inhibited by valsartan, an AT1 receptor specific blocker (P<0.05), whereas enhanced by PD123319, an AT2 receptor antagonist (P<0.05).</p><p><b>CONCLUSION</b>These results indicate that Ang II receptors regulates PI3-K/Akt cascade of hypertrophic scars fibroblasts via AT1 and AT2.</p>
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Humanos , Angiotensina II , Farmacología , Bloqueadores del Receptor Tipo 1 de Angiotensina II , Farmacología , Bloqueadores del Receptor Tipo 2 de Angiotensina II , Células Cultivadas , Cicatriz Hipertrófica , Metabolismo , Patología , Fibroblastos , Biología Celular , Metabolismo , Imidazoles , Farmacología , Fosfatidilinositol 3-Quinasas , Metabolismo , Proteínas Proto-Oncogénicas c-akt , Metabolismo , Piridinas , Farmacología , Receptor de Angiotensina Tipo 1 , Transducción de Señal , Tetrazoles , Farmacología , Valina , Farmacología , ValsartánRESUMEN
<p><b>OBJECTIVE</b>To investigate the expression and function of miR-218 in gastric cancer.</p><p><b>METHODS</b>miR-218 levels were evaluated in 20 non-cardia gastric cancer tissues using TaqMan stem-loop real-time PCR analysis. Pre-miR-218 and anti-miR-218 inhibitor were used to change the miR-218 expression level and examine its effects on cell proliferation, apoptosis, cell cycle and cell invasion.</p><p><b>RESULTS</b>Comparing with the corresponding normal tissues, miR-218 expression was significantly reduced in the gastric cancer tissue (P < 0.01). Forced expression of miR-218 increased apoptosis in AGS cells. The proportion of apoptosis cells induced by transfection of pre-miR-218 was greater than that induced by control (21.6% vs. 10.4%, P = 0.032). Pre-miR-218 resulted in a significantly decreased cell growth activity (P < 0.01) and cell invasion (P < 0.05) of AGS cells compared with that of the control.</p><p><b>CONCLUSION</b>miR-218 expression is reduced in gastric cancer. miR-218 may function as a tumor suppressor in gastric carcinoma.</p>
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Humanos , Apoptosis , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , MicroARNs , Genética , Metabolismo , Fisiología , Invasividad Neoplásica , Neoplasias Gástricas , Genética , Metabolismo , Patología , TransfecciónRESUMEN
<p><b>BACKGROUND</b>The diagnosis of small bowel diseases remains relatively inefficient using traditional imaging techniques. Capsule endoscopy (CE) and double-balloon enteroscopy (DBE) are two novel methods of enteroscopy for examining the entire small bowel. The aim of this study was to evaluate the detection rate and diagnostic accuracy of CE and DBE in patients with suspected small bowel diseases and to investigate the clinical significance of combined use of these two novel modalities.</p><p><b>METHODS</b>Two hundred and eighteen patients were evaluated for suspected small bowel disease, including 116 with obscure gastrointestinal bleeding and 102 with obscure abdominal pain or chronic diarrhea. One hundred and sixty-five out of these patients underwent CE first and 53 patients underwent DBE (under anesthesia with propofol) first. DBE was recommended after negative or equivocal evaluation on CE and vise versa. Introduction of the endoscope during DBE was either orally or anally and the patients were referred for a second procedure using the opposite route several days later when no abnormalities were found on the first procedure. The detection rates, diagnostic accuracy, tolerance and frequency of adverse events of these two modalities were then analyzed.</p><p><b>RESULTS</b>Failure of the procedure was seen in one patient with CE and in two patients with DBE. Sixty-four DBE procedures were carried out in 51 patients; by the oral route in 34 cases, the anal route in 4 and both routes in 13 cases. The overall detection rate of small bowel diseases using CE (72.0%, 118/164) was superior to that with DBE (41.2%, 21/51); chi(2) = 16.1218, P < 0.0001. The diagnostic rate (51.8%, 85/164) was also higher than that with the latter procedure (39.2%, 20/51), but was not significantly different (chi(2) = 2.4771, P > 0.05). Furthermore, the detection rate of small bowel diseases in patients with obscure gastrointestinal bleeding using CE (88.0%, 88/100) was superior to that of DBE (60.0%, 9/15); chi(2) = 7.7457, P = 0.0054. Lesions were detected by DBE in 1 out of 4 patients in whom CE had a negative result. Suspected findings by CE were confirmed by DBE combined with biopsy in 12 out of 15 patients. On the other hand, small bowel lesions were identified by CE in all 3 patients after negative evaluations by DBE. There were no severe complications during or after either of the two procedures.</p><p><b>CONCLUSIONS</b>The detection rate of small bowel diseases by CE is very high. CE should be selected for the initial diagnosis in patients with suspected small bowel diseases, especially in patients with obscure gastrointestinal bleeding. DBE appears to be inferior to CE in the diagnosis of small bowel diseases. However, it was shown that abnormalities could still be identified by DBE in patients with normal images or used to confirm suspected findings from CE. DBE can also serve as a good complementary approach after an initial diagnostic imaging using CE.</p>
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Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor Abdominal , Diagnóstico , Endoscopía Capsular , Métodos , Diarrea , Diagnóstico , Endoscopía Gastrointestinal , Métodos , Hemorragia Gastrointestinal , Diagnóstico , Enfermedades Intestinales , Diagnóstico , Intestino Delgado , PatologíaRESUMEN
<p><b>OBJECTIVE</b>To explore the regularity invading adjacent tissue of pyriform sinus carcinoma.</p><p><b>METHODS</b>The whole organ serial section of 68 total or partial laryngectomy and hypopharyngectomy specimen of pyriform sinus carcinoma were histopathologically studied.</p><p><b>RESULTS</b>In 68 pyriform sinus carcinoma, invaded ventricular and paraglottic spaces was 63 and 38 cases respectively, the difference of invasive frequency of both spaces was significantly marked (chi2 = 21.37, P < 0.01). Thyroid cartilage had the most invaded frequency of 92.6% (63/68). The all touching and pressing invasion of laryngeal cartilage was 89 times, and infiltrating invasion was 51 times. The invasive frequency of lateral cricoarytenoid muscle, posterior cricoarytenoid one, thyroarytenoid and interarytenoid ones were 63.2% (43/68), 57.4% (39/68), 55.9% (38/68), 51.5% (35/68) respectively. The invasive frequency of cricoarytenoid and cricothyroid joints were 30.9% (21/68), 17.6% (12/68) respectively. The invasive frequency of superior laryngeal nerve was 67.7% (44/65) , and more than that of recurrent laryngeal nerve (18/65, 27.7%). The pyriform sinus medial wall carcinoma was 14 cases, lateral wall carcinoma 18 cases, medial and lateral wall carcinoma 36 cases. The invaded pyriform sinus apex was 34 cases, normal its apex was 26 ones, submucous invasion of its apex was 8 ones. Light lymphocytic invasion was 66.2% (45/68) and seen most in pyriform sinus carcinoma. Submucous and leaping invasion of pyriform sinus carcinoma were 24 and 8 cases.</p><p><b>CONCLUSIONS</b>Intralaryngeal invasion of pyriform sinus carcinoma arose through paraglottic space first. Laryngeal cartilage membrane and their cartilage were anatomical obstacle against cancerous invasion. Lateral cricoarytenoid muscle, posterior cricoarytenoid one, thyroarytenoid and interarytenoid ones were often invaded. Pyriform sinus medial wall carcinoma invaded intralaryngeal structure easily, its lateral wall carcinoma may invade upward, downward and outward along thyroid cartilage interior wall, medial and lateral wall carcinoma may invade intralaryngeal and extralaryngeal structure, and was the most serious lesion. The invasion of pyriform sinus apex is an important sign of pyriform sinus carcinoma spreading downward to inferior and peripheral tissues of hypopharynx.</p>
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Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma de Células Escamosas , Patología , Neoplasias Hipofaríngeas , Patología , Invasividad Neoplásica , Estadificación de Neoplasias , Seno Piriforme , PatologíaRESUMEN
A skin cell segregating control system based on PC (personal computer) is presented in this paper. Its front controller is a single-chip microcomputer which enables the manipulation for 6 patients simultaneously, and thus provides a great convenience for clinical treatments for vitiligo. With the use of serial port communication technology, it's possible to monitor and control the front controller in a PC terminal. And the application of computer image acquisition technology realizes the synchronous acquisition of pathologic shin cell images pre/after the operation and a case history. Clinical tests prove its conformity with national standards and the pre-set technological requirements.
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Humanos , Separación Celular , Microcomputadores , Piel , Biología CelularRESUMEN
Objective To investigate the effects of Helicobacter priori (H.prlori) strains from the patient with gastric cancer on the expression of DNA mismatch repair (MMR) genes in AGS cells in vitro. Methods AGS cells were co-cultured with ten strains of H.prlori from five patients with gastric cancer and five patients with gastritis respectively.The expressions of DNA MMR genes (hMSH2 and hMLH1) in mRNA and protein levels were determined by RT-PCR and Western blot.The enteropathogenic E.coli served as a bacterial control.Results E.coli and H.priori strains from gastritis have no effects on the expression of hMSH2 and hMLH1 in both protein and mRNA levels on the whole,while all the H.prlori strains from gastric cancer reduced expression levels of hMSH2 and hMLH1.Conclusions There are different effects between H. prlori strains from gastric cancer and those from gastritis on DNA MMR in AGS cell line,indicating that infec- tion of some H.prlori strains might lead to the inhibition of DNA MMR,and that in turns increases the risk of gastric carcinogenesis during chronic H.prlori infection.