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81.
Two‐photon microscopy imaging has recently been applied to the brain to clarify functional and structural synaptic plasticity in adult neural circuits. Whereas the pain system in the spinal cord is phylogenetically primitive and easily exhibits behavioral changes such as hyperalgesia in response to inflammation, the structural dynamics of dendrites has not been analysed in the spinal cord mainly due to tissue movements associated with breathing and heart beats. Here we present experimental procedures to prepare the spinal cord sufficiently to follow morphological changes of neuronal processes in vivo by using two‐photon microscopy and transgenic mice expressing fluorescent protein specific to the nervous system. Structural changes such as the formation of spine‐like structures and swelling of dendrites were observed in the spinal dorsal horn within 30 min after the multiple‐site injections of complete Freund's adjuvant (a chemical irritant) to a leg, and these changes continued for 5 h. Both AMPA and N‐methyl‐D‐aspartate receptor antagonists, and gabapentin, a presynaptic Ca2+ channel blocker, completely suppressed the inflammation‐induced structural changes in the dendrites in the spinal dorsal horn. The present study first demonstrated by in vivo two‐photon microscopy imaging that structural synaptic plasticity occurred in the spinal dorsal horn immediately after the injection of complete Freund's adjuvant and may be involved in inflammatory pain. Furthermore, acute inflammation‐associated structural changes in the spinal dorsal horn were shown to be mediated by glutamate receptor activation.  相似文献   
82.
83.

Background/Aims

Colonic diverticular bleeding can stop spontaneously or be stopped by endoscopic hemostasis. We analyzed the clinical and colonoscopic features of patients with colonic diverticular bleeding to establish the predictive factors for rebleeding.

Methods

A total of 111 patients (median age, 72 years) with colonic diverticular bleeding in Aso Iizuka Hospital between April 2007 and July 2010 were enrolled. Age, sex, body mass index (BMI), comorbidity, medication, location of bleeding, colonoscopic findings and hemostatic methods were analyzed retrospectively from the hospital records.

Results

The most common sites of bleeding were the ascending (39.6%) and sigmoid (29.7%) colon. Overt rebleeding occurred in 30 patients (27.0%). Spontaneous hemostasis was seen in 81 patients (73.0%), and endoscopic hemostatic treatment was performed in 30 patients. The BMI in the patients with colonic diverticular rebleeding was significantly higher than in patients without rebleeding. Colonoscopic findings of actively bleeding or nonbleeding visible vessels in the responsible diverticula were more frequent in the group with rebleeding.

Conclusions

A higher BMI and colonoscopic findings of actively bleeding or nonbleeding visible vessels can be used as predictive factors for colonic diverticular rebleeding. Patients with such findings should be carefully followed up after hemostasis of the initial colonic diverticular bleeding.  相似文献   
84.
85.
The cell cycle was determined in early passage fibroblasts from Werner's syndrome and normal subjects. The average cell cycle time was prolonged in Werner's syndrome cells due to changes in the duration of S phase. Using alkaline sucrose gradient sedimentation, the rate of DNA elongation was examined, and no difference was observed between Werner's syndrome cells and normal cells.  相似文献   
86.
We report a 53-year-old man with aortic dissection, in whom pulsed Doppler echocardiography showed two different flow patterns within the dilated aorta. Although two-dimensional echocardiography has been successful in making the diagnosis of aortic root dissection, several conditions producing false positives have also been noted. Simultaneous recording of pulsed Doppler echocardiography may be useful to provide additional diagnostic clues in selected cases.  相似文献   
87.
Background: Background: We previously demonstrated that the immunostaining of the gap-junction protein, connexin 32 (Cx 32), in the pancreas was markedly reduced in caerulein (Cn)-induced acute pancreatitis. The expression of Cx 32 in the pancreas during the course of acute pancreatitis is unclear. To address this, we examined Cx 32 mRNA and protein expression in the pancreas. Methods: Cx 32 mRNA and protein expression in the pancreas was examined by Northern blot analysis and Western blot analysis, respectively, 1, 4, 7, and 14 days after the induction of acute pancreatitis. Results: Cx 32 mRNA was identified in normal rat pancreas, and the value for the relative intensity against 18S rRNA was 0.57 ± 0.15 (mean ± SD). After the induction of acute pancreatitis by caerulein, the Cx 32 mRNA expression levels were increased on day 1, day 4, day 7, and day 14 compared with levels in the normal pancreas (1.63-fold, 1.61-fold, 1.49-fold, and 1.35-fold, respectively). A significant increase in Cx 32 protein expression was detected on day 1 and day 4 (1.67 ± 0.15-fold and 1.72 ± 0.2-fold, respectively), while Cx 32-positive spots, determined by immunohistochemical analysis, were markedly decreased on day 1 and had returned to normal by day 14. Conclusions: These results show that the expression of Cx 32 increases early on after the induction of pancreatitis by Cn, and that the normalization of Cx 32-immunostained spots in Cn-induced acute pancreatitis occurs after the increase in Cx 32 mRNA and protein expression. Received: July 10, 2001 / Accepted: January 18, 2002  相似文献   
88.
The position of the distal retinal pigments was measured in the eyes of Palaemon which had been exposed to various light intensities (0-2000 lux) for periods up to 7 days. Electron microscopical observations of sinus glands from these animals revealed that long-term illumination (1000 lux, 7 days) resulted in almost complete degranulation of the Type 2 axon terminals, reflecting intense discharge of the granules. On the other hand, the Type 2 terminals of dark-adapted prawns showed no signs of hormone release, such as exocytosis. The results indicate that the light-adapting hormone is liberated from Type 2 terminals. The Type C cell somata in the medulla terminalis, containing granules of similar size to those in the Type 2 terminals, may be the site of synthesis of this hormone.  相似文献   
89.
The morphological substrate for the central mechanisms that control growth hormone (GH) release in the rat hypothalamus was investigated immunohistochemically by light and electron microscopy. In electron-microscopic studies, a dual immunolabeling technique was employed to demonstrate pairs of peptides, i.e. rat hypothalamic growth hormone-releasing factor (rhGRF) and somatostatin (SRIH), rhGRF and substance P (SP), and rhGRF and methionine-enkephalin-Arg6-Gly7-Leu8 (Enk-8), in different neuronal structures. Immunoreactivity of rhGRF was detected as silver-gold particles and those of the other substances as diaminobenzidine products by preembedding immunostaining procedures. In the external layer of the median eminence, axonal terminals immunolabeled for rhGRF and for SRIH showed the same pattern of distribution and close proximity. The neuronal inputs to GRF cell bodies in the arcuate nucleus were examined, and SRIH, SP and Enk-8 fibers with varicosities were found to form dense networks around the perikarya of GRF neurons, suggesting the presence of synaptic associations. Axonal terminals immunolabeled for SRIH, SP or Enk-8, and unlabeled terminals appeared to form coincidental synaptic junctions on GRF perikarya. These findings suggest that the central regulation of GH release occurs at the levels of the median eminence and the cell bodies.  相似文献   
90.
A 42-year-old woman was admitted with abnormal chest radiographs. Though interstitial pneumonia associated with dermatomyositis was diagnosed, her chest radiograph also revealed a narrowed trachea about 6 mm in diameter. Bronchoscopy showed that her trachea lacked a membranous posterior segment and O-shaped complete tracheal rings were present throughout the trachea, indicating congenital tracheal stenosis. Congenital tracheal stenosis is a rare disorder and is usually recognized in the first few weeks of life, but the patient had no history of dyspnea or recurrent pneumonia. This case suggests that among healthy people there are a very few who have asymptomatic congenital tracheal stenosis.  相似文献   
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