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81.
The synthesis, intracellular translocation, and secretion of mannose-containing glycoproteins(s) by periodontal ligament fibroblasts have been investigated by means of electron microscopic radioautography. Tritiated mannose was administered to young mice via jugular vein, and radioautographs were prepared at 5, 10, 20, and 35 minutes, 4 and 8 hours after injection. Analysis of electron microscopic radioautographs revealed a maximum labeling (94%) with 3H-mannose of the rough endoplasmic reticulum at 5 minutes. Labeling of the Golgi components started to increase from 10 minutes (14%) and reached a maximum level at 20 minutes (31.2%). At 35 minutes, secretion granules, dense bodies, profiles of intracellular collagen, and the cell surface were labeled. At 8 hours, most labelling (79.2%) was extracellular, and associated either with the collagenous matrix (43.7%) or the cell surface (35.5%). Cytoplasmic vesicles containing dense materials around collagen fibrils were also labeled at 8 hours. It is concluded that mannose is directly incorporated into the rough endoplasmic reticulum (RER), and that mannose-containing glycoprotein(s) are packaged in the Golgi apparatus into secretory granules. Mannose-containing glycoprotein(s) become distributed on the periodontal ligament (PDL) fibroblast cell surface, cytoplasmic dense bodies, and the extracellular matrix.  相似文献   
82.
p53 codon 72 polymorphism and risk of cervical carcinoma in Korean women   总被引:3,自引:0,他引:3  
A common polymorphism of the wild type p53 is known at codon 72 of exon 4, with 2 alleles encoding either arginine (CGC, p53Arg) or proline (CCC, p53Pro). A recent study suggested that this polymorphism affects the susceptibility of p53 protein to human papillomavirus E6 oncoprotein mediated degradation and that individuals homozygous for p53Arg are seven times more susceptible to HPV-associated carcinogenesis of the cervix than heterozygotes. To examine whether the p53Arg genotype could be a risk factor for HPV-associated cervical carcinomas in the Korean population, we analyzed the p53 codon 72 polymorphism status of HPV-positive invasive cervical carcinomas from 52 Korean women and 103 healthy control samples. The proportion of individuals homozygous for p53Arg, homozygous for p53Pro, and heterozygous for the two alleles were 40%, 19%, and 41% in normal healthy controls; 42%, 17%, and 40% in women with HPV-positive invasive cervical carcinoma. There were no significant differences in the distribution of p53 genotypes between controls and cervical carcinomas. This finding indicates that the p53Arg genotype is not associated with an increased susceptibility to cervical carcinoma in Korean women.  相似文献   
83.
We recently treated two cases of chronic pancreatitis with obstructive jaundice due to compression of the common bile duct by pancreatic pseudocyst. The two cases were males admitted with the complaint of icteric skin color. The first, a 46-year-old male, admitted with the complaint of icteric skin color. He was treated by operative cystojejunostomy after percutaneous drainage of the pseudocyst and percutaneous transhepatic biliary drainage. The other case was a 58 year-old male who admitted with the complaint of icteric skin color. He had an infected pseudocyst in the pancreas and was endoscopically treated. Both of them were discharged with favorable clinical course and normal laboratory findings after the treatment. The former patient remained well 11 months after treatment, but the latter patient died from necrotizing pancreatitis and septic shock 6 months after treatment. Most cases of obstructive jaundice associated with pseudocysts appear to be due to fibrotic stricture of the intrapancreatic portion of the common bile duct rather than due to compression of the bile duct by the pseudocyst. In a patient with secondary pancreatic infection or obstructive jaundice following pancreatic disease, differentiating between these two conditions is an important aspect of accurate diagnosis and therapy. Herein we report two unusual cases of chronic pancreatitis with pseudocyst complicated by obstructive jaundice.  相似文献   
84.
Chung Y  Cho J  Chang YS  Cho SH  Kang CY 《Immunobiology》2002,206(4):408-423
Allergic asthma is an inflammatory disease of the airways, and Th2 cells secreting IL-4 and IL-5 play a pivotal role in its pathogenesis. We have previously demonstrated that oral tolerance can be induced and maintained more profoundly in a Th2-related immune response, and that an ongoing immune response can be suppressed by the oral administration of antigen combined with an appropriate feeding regimen. In the present study, we examined the preventive and therapeutic effects of the oral administration of allergen on a Th2-mediated immune disorder using a murine model of asthma. Our results show that the development of asthma can be blocked completely by orally administering allergen. Airway hyperreactivity, allergen-specific IgE production, Th2-derived cytokines, allergen-induced T cell proliferation and the infiltration of inflammatory effector cells into the lung were prevented by such oral administration. To assess the therapeutic effects of oral administration on the progression of asthma, we tested the effects of oral tolerance in an established asthma model, and found that a multiple high dose-feeding regimen was effective at suppressing the progression of mild asthma. In the high dose-feeding group, the number of eosinophils in bronchoalveolar lavage fluid was reduced and airway reactivity also decreased. However, this was insufficient to reduce airway reactivity and eosinophilia in bronchoalveolar lavage fluid in cases of severe asthma. These results demonstrate that allergic asthma may be ameliorated by feeding allergen; there is hope that these results will provide a new immunotherapeutic strategy for allergic asthma.  相似文献   
85.
Previous molecular genetic studies of laryngeal squamous cell carcinoma (SCC)have shown certain chromosomal regions with recurring alterations. But studies of sequential molecular alterations and genetic progression model of laryngeal SCC have not been clearly defined. To identify the chromosomal alterations associated with the carcinogenesis of laryngeal SCC, we analyzed genomic DNA from microdissected squamous metaplasia, squamous dysplasia, invasive SCC, and metastatic carcinoma samples from 22 laryngeal SCC patients for loss of heterozygosity (LOH) at microsatellite loci. Ten microsatellite markers on chromosome 3p, 8p, 9p, and 17p were used. LOH at 9p21 was observed in the all stages including squamous metaplasia, squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 17p13.1, 3p25 and 3p14.2 was observed from the squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 8p21.3-p22 was observed mainly from the invasive SCC and metastatic carcinoma. The results suggest that 9p21 in the early event, 17p13.1, 3p25 and 3p14.2 in the intermediate event and 8p21.3- p22 in the late event may be involved in the laryngeal carcinogenesis.  相似文献   
86.
Brain tumors in infants present special diagnostic and therapeutic challenges. To figure out the clinical features, pathological classification of the tumors and the treatment outcome of infantile brain tumors, 458 children (age<16) with brain tumors were reviewed retrospectively. Among them 21 cases (4.6%) were diagnosed during the first 12 months of life. Two tumors were definitely of congenital origin. The majority of infants with brain tumors presented with increased intracranial pressure. Fourteen tumors were located at the supratentorial area. Sixteen cases had neuroepithelial tumors; astrocytoma (optic pathway), supratentorial primitive neuroectodermal tumor (PNET) and medulloblastoma were found in three cases each. There were two treatment-related mortalities. Compared with the outcomes in older children, the treatment outcome was poorer in medulloblastoma and the optic pathway glioma which showed a higher growth potential. Because of the limited application of postoperative adjuvant therapy, radical surgical removal played a more important role in this age group. The prognosis of patients in whom the tumors could not be totally removed, largely depended on the pathological malignancy of the tumors. Though the treatment outcome was not always dismal, immaturity of the brain, higher growth potential, perioperative risks, limitations in adjuvant therapy, and pessimistic attitude on the part of parents made management more challenging.  相似文献   
87.
The hypertensive-diabetic rat is a new small animal model of cardiomyopathy characterized by ventricular damage. To determine the extent of pathology in this model, quantitation of light microscopic changes in hearts from 15 hypertensive-diabetic rats and 15 age-matched controls was performed. The fraction of myocardium involved by interstitial fibrosis, myocyte necrosis, replacement fibrosis, vascular sclerosis and perivascular fibrosis was computed separately for right and left ventricles. Spontaneously dying as well as deliberately killed hypertensive-diabetic rats were studied. Spontaneously dying animals had higher systolic blood pressures compared with rats killed deliberately. Body weights were lower and lung weights higher in the former group. Left and right ventricular necrosis and fibrosis were increased in spontaneously dying compared with deliberately killed rats. The degree of right ventricular necrosis and fibrosis paralleled that in the left ventricle, but was, unexpectedly, several times greater in magnitude. Thus, quantitative histology in the hypertensive-diabetic rat reveals more cardiac necrosis and fibrosis, in either ventricle, from spontaneously dying animals compared with deliberately killed rats. This damage, coupled with major functional alterations in the viable myocardium, may lead to congestive heart failure or arrhythmia.  相似文献   
88.
BACKGROUND AND PURPOSE: The optimal intensity fluence profile of a beam depends on the profiles of other beams but most optimizations assume fixed beam orientations, a priori. Breast cancer radiotherapy attempts to cover the target and to spare critical structures such as the heart and lungs. The study aims are (1) to determine and document the optimal two-beam orientation that best spares the heart for left-sided breast cancer patients and (2) to investigate the influence of the treatment technique (i.e., conformal versus intensity modulation) on the optimal objective cost function. MATERIAL AND METHODS: Ten left-sided breast cancer patients were planned using a conformal (3DCRT) and a simplified intensity modulated (sIMRT) technique using predefined segments and different two-beam orientations. Optimal segment weights were determined exhaustively for all axial two-beam combinations, in 5 degree increments, by minimizing a quadratic objective cost function. The resulting objective cost function was analyzed with respect to target geometry and treatment technique. RESULTS: The sIMRT plans are generally less sensitive to beam orientation compared to 3DCRT plans. Optimal two-beam orientations for 3DCRT and sIMRT plans exist and they correspond to a hinge angle of approximately 188 degrees and 160 degrees or 210 degrees (the latter is bimodal), respectively. CONCLUSIONS: The optimization software is a useful tool that can test many different beam combinations and estimate their associated objective cost values. Afterwards, the most promising beam orientations could be re-optimized under the TPS to fine-tune and verify the dose distributions. Optimal uniform two-beam orientations for the breast consist of opposing tangential medial and lateral beams. Optimal nonuniform two-beam orientations for left-sided breast cancers are bimodal, containing hinge angles around 160 degrees and 210 degrees. Nonuniform beam techniques are less sensitive to beam orientation compared to uniform beam techniques and result in significantly improved heart sparing but at a cost of slightly compromised planning target volume coverage.  相似文献   
89.
p-Carboxyphenoxy propane (CPP) prepolymer consisting of 4 units and sebacic acid (SA) prepolymer consisting of about 10 units were synthesized by reacting CPP and SA in the presence of excess acetic anhydride, respectively. Polyanhydride, poly(CPP-SA) copolymers were copolymerized by a melt polycondensation process with a mixture of CPP and SA prepolymer. Copolymers of average molecular weight up to 110,000 g/mol were achieved. The crystallinity of poly(CPP-SA) copolymers was decreased by the addition of the CPP homopolymer segment to SA homopolymer. Poly(CPP-SA) copolymers gradually degraded for period of 10 days. No large difference of weight loss observed according to molecular weight variation of poly(CPP-SA) copolymers. BCNU release from wafers fabricated by poly(CPP-SA) showed a sustained release pattern with no initial burst and delay of drug release.  相似文献   
90.
Loss of the cell adhesion molecule E-cadherin is suggested to promote tumor invasion and distant metastasis in tumor development. Recently, it has been proposed that E-cadherin function requires its linkage to the cytoskeleton through catenins. We evaluated the expression of E-cadherin and alpha-, beta-, gamma-catenins in tissues of human endometrial carcinoma, analyzed the patterns of cell adhesion molecules' expression in endometrial carcinoma and investigated the relationship between the statuses of cell adhesion molecules and various clinicopathological factors. This study investigated the immunohistochemical expression of E-cadherin and alpha-, beta-, gamma-catenins in 33 paraffin embedded formalin fixed tissues of endometrial carcinomas. Aberrant E-cadherin, and alpha-, beta-, gamma-catenin expression was observed in 33.3 (11 of 33), 27.3 (9 of 33), 18.2 (6 of 33), and 51.5 (17 of 33) % of the specimens, respectively. Statistically significant correlation was found between aberrant expression of E-cadherin and lymph node metastasis and cell types other than endometrioid adenocarcinoma. Aberrant pattern of gamma-catenin expression was also correlated with deep myometrial invasion. However, alpha-, and beta-catenin expression was not correlated with any clinicopathological parameters. Using the Kaplan-Meier method and log-rank comparison test, abnormal expression of E-cadherin was correlated closely with poor survival (p < 0.05), but cases with loss of both E-cadherin and catenin expression predicted even poorer survival than cases with only one or no aberrant expression in E-cadherin and catenins. We revealed aberrant expression of these cell adhesion molecules among patients with endometrial carcinoma. Aberrant expression of E-cadherin was correlated with lymph node metastasis and cell types other than endometrioid adenocarcinoma, while aberrant expression of gamma-catenin was related with deep myometrial invasion. The expression of E-cadherin might be a possible prognostic factor for endometrial cancer while the expression of catenins may help predict patient's survival.  相似文献   
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