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91.
We sometimes experience patients with persistent or progressive arytenoid edema, among which residual or recurrent cancer is often accompanied. Because it is difficult to distinguish tumour rest or recurrence from normal tissue sequelae in the early period after irradiation, it is important to know both the contributing factors for arytenoid edema, and the incidence of residual or recurrent tumours in patients with postirradiation laryngeal edema. We therefore reviewed the charts of 67 patients with early laryngeal carcinoma who had received a curative dose of irradiation in the last 5 years. Fourteen patients (20.9%) had moderate or severe laryngeal edema persisting for or developing at more than 3 months after completion of a course of definitive radiotherapy. The incidence was highest in supraglottic T2 disease, followed by glottic T2 tumour. Of the 14 patients with edema, six (42.9%) had persistent or recurrent disease. The primary disease was uncontrolled in 18 patients, 17 of whom received successful salvage surgery. In patients without residual tumours, the edema was usually moderate and resolved within a year, although four patients had chronic edema lasting more than a year after treatment. All four had supraglottic T2 lesions and received 70 Gy of X-ray. We also reviewed, for sake of comparison, the records of 38 patients treated with radiotherapy at doses of more than 40 Gy between l975 and 1980, when endoscopic microsurgery for laryngeal cancer was introduced as a primary part of treatment. The incidence of persistent or late developed edema over the period, though not significant, was 36.8%: nearly twice that of the last 5 years. Microscopic endolaryngeal surgical procedures seem to have been a causal factor for edema in this period.  相似文献   
92.
93.
Background. The phenotypic expression of tumor cells is widely thought to resemble that of the tissue of origin. In the present study, to assess phenotypic changes that occur with disease progression, we investigated human differentiated gastric cancers at different depths of invasion for component cancer cell types. Methods. Using a combined mucin histochemical and immunohistochemical approach, we classified surgical specimens of 301 differentiated gastric cancers into three types: gastric epithelial cell (G) type, intestinal epithelial cell (I) type and mixed gastric and intestinal (GI) type, according to the phenotypic differentiation of the component cancer cells. The relation between the phenotypic type of cancer and their depth of invasion was evaluated. Results. The proportion of G type cancers was 41.4% in early (tumor invasion of mucosa or submucosa) cases, decreasing to 22.2% in advanced (tumor invasion of muscularis propia or deeper) cases, whereas the proportion of I type cancers increased with progressive disease from 23.5% to 31.1% (P < 0.01). Cancers invading the subserosa or deeper included more I type cases and fewer G type than cancers limited to the mucosa (P < 0.01). In most cases of each phenotypic type, intestinal metaplasia was recognized in the surrounding background mucosa, but no clear relation was shown between the phenotype of cancers and the degree of intestinal metaplasia in the background mucosa, suggesting that intestinal metaplasia is not always a preneoplastic lesion. Conclusions. A phenotypic shift from G to I type expression was observed with the progression of human differentiated gastric cancers. Intestinalization may occur independently in cancerous and noncancerous gastric mucosa. Received for publication on May 1, 1998; accepted on Oct. 22, 1998  相似文献   
94.
The locus coeruleus (LC), located within the caudal pontine central gray, is composed of noradrenaline-containing neurons. The axons of these neurons form extensive collateral branches that project widely to many brain sites. The function of the LC is still unclear at present, however, LC neurons are known to exhibit marked axonal regeneration and sprouting in response to brain damage. We investigated the age-related changes in noradrenergic innervations of the frontal cortex, using in vivo electrophysiological techniques and immunohistochemistry. While noradrenergic innervations gradually decreased with age in the frontal cortex, a high degree of sprouting occurred in the LC axon terminals in middle age. Neither the electrophysiological properties of LC neurons nor NA levels in the frontal cortex changed with age. These findings suggested that the LC neurons preserve a strong capacity to remodel their axon terminals even in the aging brain. Exogenous brain-derived neurotrophic factor (BDNF) infusion caused a marked increase in the density of noradrenergic axon in the aged brain, but no trophic action of BDNF was observed in the young or middle-aged brain. The result suggests that BDNF is necessary for the maintenance of noradrenergic innervations in the aged brain.  相似文献   
95.
To examine the role of c-Jun N-terminal kinase (JNK/SAPK) in the developing nervous system of vertebrates, the localization of an active form of JNK, phosphorylated JNK (p-JNK), was studied in the lumbosacral spinal cord of the chick embryo. We also examined the localization of phosphorylated neurofilaments (NFs, potential targets of p-JNK) and cyclin-dependent kinase 5 (Cdk5), which is known to phosphorylate cytoskeletal proteins, including NFs, and compared their expression with that of p-JNK. Additionally, the localization of phosphorylated forms of c-Jun and ATF-2 was compared with that of p-JNK. On embryonic day 3 (E3), the expression of p-JNK was observed in regions containing early-projecting axons. Axons in these regions also expressed phosphorylated NFs. Subsequently, on E5 and E8, the expression of both p-JNK and phosphorylated NFs increased concomitantly in the axonal tracts in the spinal white matter. Thus, white matter expressed both p-JNK and phosphorylated NFs, whereas there was only weak expression of Cdk5. By E13, the spinal cord expression pattern of p-JNK and phosphorylated NFs had changed compared to earlier ages. Although phosphorylated NFs were still expressed in the white matter, the expression of p-JNK was decreased in axons in the white matter, whereas strong p-JNK expression appeared in cell nuclei in the gray matter. In summary, the present study revealed that the localization of p-JNK in the spinal cord changes dramatically from axons to cell nuclei during development, suggesting multiple roles of p-JNK, depending on the developmental age.  相似文献   
96.
Two patients with postoperative interstitial pneumonia are reported. Preoperative diagnosis was primary lung cancer without idiopathic interstitial pneumonia (IIP). Within one week after operation acute interstitial pneumonia (AIP) occurred on the nonoperated side and developed. Steroid therapy was performed but one was dead. AIP is a fatal complication after pulmonary resection and steroid therapy may be useful in some cases of postoperative AIP.  相似文献   
97.
Schwann cells participate in myelin phagocytosis in the early stage of Wallerian degeneration, prior to the recruitment of macrophages. This is the first report that Schwann cells induce heme oxygenase-1 (HO-1), a 32-kDa heat shock protein, only when they have transformed into myelin-phagocytosing cells from myelinating cells (days 2-3) immediately after crush injury of rat sciatic nerves. Double immunofluorescent labelling for HO-1 and transferrin receptors revealed that HO-1-immunoreactive Schwann cells also expressed transferrin receptors suggesting activation of iron metabolism. The transient induction of HO-1 in Schwann cells may contribute to the adaptive function in an altered environment when the cells have lost contact with axons, and may play a crucial role in the ensuing regeneration.  相似文献   
98.
BACKGROUND: Anastomotic complications associated with bronchoplastic procedures cannot be completely avoided despite the improvements made in surgical techniques and suture materials. Thus, the present study attempted to clearly define the significant factors influencing anastomotic complications. METHODS: Between 1978 and 1998, 47 patients with primary nonsmall cell lung cancer underwent bronchoplastic procedures. The incidences of anastomotic complications were calculated according to each of the following clinical factors: primary site, age, pathologic type, pT factor, pN factor, pulmonary arterioplasty, surgical procedure, suture material, coverage of the anastomotic line, positive resection margin, and preoperative chemotherapy. The results were analyzed using univariate and multiple logistic regression analysis. RESULTS: Anastomotic complications occurred in 8 patients. Four had anastomotic dehiscence and 4 had stenosis. Of these 8 patients, the resection margin was diagnosed as being positive in 6 patients. Three showed metastasis of the most distal mediastinal lymph node whereas the others had a residual tumor at the bronchial resection margin. According to multiple logistic regression analysis, only pN factor (p = 0.04) and positive resection margin (p = 0.02) had a significant influence on the complications. CONCLUSIONS: Thus, pN2 patients, especially those with metastasis of the most distal mediastinal lymph node and patients with a residual tumor at the bronchial resection margin, have a significantly higher risk of anastomotic complications.  相似文献   
99.
Revascularization of canine cryopreserved tracheal allografts   总被引:10,自引:0,他引:10  
Background. We examined the blood supply of a cryopreserved tracheal allograft and its morphohistologic changes after transplantation.

Methods. In each of 22 dogs, a five-ring tracheal segment was replaced by one of the following tracheal grafts: fresh autografts (n = 8), cryopreserved tracheal allografts (n = 8), or fresh allografts (n = 6). The cryopreserved tracheal allografts were preserved at −196°C for 60 days. No immunosuppressant was given to any of the animals. All grafts were retrieved at 1 and 12 weeks and assessed by microangiography and histology.

Results. The epithelial denudation and the revascularization of the transverse intercartilaginous arteries were recognized within 7 days as common to each of the three types of grafts. In the cryopreserved tracheal allografts, neither cartilage degradation nor graft shrinkage occurred at 7 days. However, the recanalized transverse intercartilaginous arteries completely disappeared at 12 weeks, and marked shrinkage occurred; the cartilage cells were accompanied by karyolysis and were significantly decreased in number (p < 0.05). Recanalization of the transverse intercartilaginous arteries was also demonstrated in the fresh allografts; however, necrosis abruptly occurred as a result of acute rejection responses.

Conclusions. Cryopreservation of a tracheal allograft provided sufficient reduction of the acute rejection responses, and blood supply to the cryopreserved tracheal allograft was established through the recanalized transverse intercartilaginous arteries within 7 days; however, subsequent chronic rejection responses resulted in occlusion of the transverse intercartilaginous arteries and atrophy.  相似文献   

100.
Non-immunosuppressive immunophilin ligands (NI-IPLs) are attracting attention as new candidate drugs for neuroprotection and/or neurorestoration, particularly since they do not have the adverse effects of immunosuppressants. However, it is not yet enough to understand that NI-IPLs are useful drugs for treating neurological disorders. In particular, the molecular mechanism of NI-IPL activity in target cells in the brain remains obscure. In this review, we focused on the molecular basis of the neuroprotective properties of IPLs. Our findings suggest that IPLs have neuroprotective effects mediated by multiple beneficial properties such as a glutathione (GSH)-activating effect, a neurotrophic factor (NTF)-activating effect, and an anti-apoptotic effect, but not by an immunosuppressive effect, both in cell cultures and in vivo. In particular, the GSH-activating effect and the NTF-activating effect of NI-IPLs may be essential to the expression of their neuroprotective properties. Thus, NI-IPLs might have a potentially beneficial effect by ameliorating neurological disorders, since they do not cause serious side effects such as immune deficiency.  相似文献   
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