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11.
12.

Background

Nodal metastasis is an important clinical issue in gastric cancer patients. This study was designed to investigate the clinical usefulness of the positive lymph node ratio (PLNR), which reflects both metastatic and retrieved lymph node numbers, in patients with pN3 gastric cancer.

Methods

We retrospectively analyzed the records of 138 consecutive pN3 patients who underwent curative gastrectomy with lymphadenectomy from 2000 to 2012.

Results

A PLNR of 0.4 was proved to be the best cutoff value to stratify the prognosis of patients with pN3 gastric cancer (P?<?0.001). Univariate and multivariate analyses revealed that older age, larger tumor size (≥10 cm), and PLNR?≥?0.4 [P?<?0.001, HR 3.1 (95 % CI 1.7–5.4)] were independent prognostic factors in pN3 gastric cancer. Regarding the recurrence, patients with PLNR <0.4 had a significantly lower rate of lymph node recurrence than those with PLNR ≥0.4 (P?=?0.020). There was no significant difference in the lymph node recurrence rate between N3a and N3b patients in the PLNR <0.4 group [P?=?0.546, 11.6 % (7/60) vs. 12.5 (1/8)], indicating a better local control regardless of pN3 subgroups.

Conclusions

PLNR is useful to stratify the prognosis and evaluate the extent of local tumor clearance in pN3 gastric cancer.
  相似文献   
13.
A 90-day ad libitum administration toxicity study of oligoglucosamine (OG) was carried out using F344 rats of both sexes. The animals were divided into four groups of 20 animals each, 10 of each sex, and fed a diet containing 0, 0.04, 0.2 or 1.0 (w/w)% OG. During the administration period, no animals of either sex died or exhibited abnormal signs in the 0.04% OG and 0.2% OG groups. In the 1% OG group, in both sexes, erythema and swelling of the snout and forelimbs and loss of fur in the forelimbs were observed. On macroscopic observation, emaciation, swelling of the snout, auricles and forelimbs and alopecia of the forelimbs were also observed in 2-3 males of the 1% OG group. It was suggested that these topical abnormalities might be due to dermal responses to OG adhering to the skin and fur, which are easily soiled with saliva during grooming. In the animals of the 1% OG group, food consumption decreased, resulting in body weight gain being suppressed. This was found concomitantly with the abnormal findings mentioned above. Thus, feeding difficulties due to the topical lesions on the snout and forelimbs were thought to affect body weight. In hematology, platelet count, lymphocyte count and differential neutrophil count increased in males of the 1% OG group. These changes might be related to the dermal inflammation. Abnormalities in urinalysis and blood chemistry, as well as a small thymus, small spleen, dark spots or areas on the glandular stomach mucosa, pale Harderian glands and small testes in histopathology, were also observed in males in the 1% OG group. Whether or not all these changes were related only to the malnutrition remains to be elucidated. From these results, OG gave rise to no adverse effects in rats up to the dose level of 0.2 (w/w)%. Thus, the no observed adverse effect level was determined to be 0.2 (w/w)% for rats of either sex (124.0mg/kg/day in males, 142.0mg/kg/day in females).  相似文献   
14.
PURPOSE: To investigate the functional properties, subcellular localization, and chromosomal location of retinal fascin. METHODS: Recombinant retinal fascin protein was prepared by using a baculovirus-insect expression system. Actin-binding and -bundling assays were performed with chick actin purified from skeletal muscle. Western blot analysis and immunohistochemistry were performed with a polyclonal antibody raised against bovine retinal fascin. A human retinal cDNA library was screened with an expressed sequence tag cDNA fragment. Chromosomal location was determined with fluorescent in situ hybridization. RESULTS: The actin-binding and actin-bundling activities of retinal fascin were demonstrated by high- and low-speed centrifugation assays. Formation of filamentous (F)-actin bundles by retinal fascin in vitro was also morphologically confirmed by fluorescence microscopy and electron microscopy. Immunohistochemical analysis revealed that retinal fascin protein was localized specifically in the outer and inner segments of the photoreceptor cells in the retina. Two splicing variants of human retinal fascin cDNA were also located. One clone encoded 492 amino acids, and the other encoded 516 amino acids. The gene encoding retinal fascin was localized to human chromosome 17, region q24 -25. CONCLUSIONS: These results suggest that retinal fascin may play a role in formation of unique morphologic structures of the photoreceptor cells and is a candidate gene for retinal degenerative disorders.  相似文献   
15.
PURPOSE: To describe anterior optic neuritis in adult measles infection.DESIGN: Interventional case report. METHODS: A 31-year-old woman presented with bilateral visual loss 6 days after the onset of maculopapular rash. Complete ophthalmic and neurologic examinations, radiologic studies, and lumbar puncture were performed. RESULTS: Visual acuities were counting fingers in both eyes, with bilateral optic disk hyperemia and swelling noted. Neurologic examination was unremarkable, and computed tomography and magnetic resonance imaging of the brain were normal. The cerebrospinal fluid (CSF) was devoid of white cells, although measles immunoglobulin M (IgM) antibodies were detected in both CSF and serum. Intravenous corticosteroids were administered, and clinical findings resolved within 1 month. A fall in serum IgM and a rise in serum IgG titers were observed. CONCLUSIONS: Although rare, optic neuritis in the absence of encephalomyelitis may occur in measles. Whether treatment is effective is unknown.  相似文献   
16.
PURPOSE: To evaluate photoreceptor cell-specific adenosine triphosphate (ATP)-binding cassette transporter (ABCA4) gene mutations in Japanese patients with Stargardt disease (STGD) and the correlation of these mutations to clinical phenotypes. METHODS: Serum was obtained from 10 unrelated Japanese patients with STGD and 96 unrelated Japanese patients with autosomal recessive retinitis pigmentosa (arRP). All 50 ABCA4 gene exons of the patients with STGD were screened for mutations by a combination of single-strand conformation polymorphism analysis and polymerase chain reaction (PCR) direct-sequencing techniques. By restriction enzyme digestion, primer extension analysis, and PCR direct sequencing techniques, the patients with arRP were screened for three segregated, presumably null ABCA4 gene mutations observed in Japanese patients with STGD. RESULTS: Three novel, presumably null mutations of the ABCA4 gene, IVS7-45_952delinsTCTGACC, IVS12+2T-->G, and 1894delA, were identified. The Arg2149stop mutation that had been found in a white patient with STGD in a prior study was also found in a Japanese patient. Two arRP-affected siblings and two unrelated patients with STGD were found to be homozygous for the same IVS12+2T-->G mutation, and three other arRP-affected siblings were carriers of the IVS12+2T-->G mutation and/or the IVS7-45_952delinsTCTGACC mutation. These three siblings with arRP showed only atrophic degeneration in the macula early after the onset of the disease, and STGD had been diagnosed. CONCLUSIONS: Three novel ABCA4 gene mutations were identified in Japanese patients with STGD and arRP. Mutations in the ABCA4 gene can cause panretinal degeneration that changes its clinical appearance from STGD to arRP over time.  相似文献   
17.
The strong association between chronic inflammation and development of cancer is well-established in chronic inflammatory states. Nitric oxide (NO) is generated by inflammatory cytokines due to the action of inducible nitric oxide (iNOS), oxidizing DNA to form 8-hydroxy-2'-deoxyguanosine (8-OHdG) adducts, a major species of oxidative DNA damage. In the present study, we investigated the enhancing effect of carbon tetrachloride, a typical hepatotoxic chemical, on rat 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) hepato-carcinogenesis. A total of 420, 21-day-old, male Fisher 344 rats were given MeIQx at a concentration of 0, 0.001 ppm (human exposure level), 0.01, 0.1, 1, 10 and 100 ppm in the diet, and each group was separated into carbon tetrachloride-treated and vehicle-treated subgroups. Carbon tetrachloride was given by subcutaneous (s.c.) injection twice a week at a dose of 0.125 ml/kg body weight (b.w.) for the first 10 weeks and then at 0.25 ml/kg b.w. during the next 10 weeks. All rats were sacrificed at the end of week 22. In the vehicle-treated animals, only 100 ppm MeIQx significantly increased the number of glutathione S-transferase placental form (GST-P)-positive foci in the liver compared with 0 ppm MeIQx. Co-administration of carbon tetrachloride enhanced the induction of GST-P-positive foci by MeIQx in each group and the curve was almost the same pattern as that of vehicle-treated group but their numbers were significantly enhanced with 10 ppm and above compared with 0 ppm MeIQx. Persistent liver injury and liver cell proliferation were histopathologically observed in carbon tetrachloride-treated groups. Increase of 8-hydroxydeoxyguanosine (8-OHdG) formation and iNOS overexpression were observed by co-administration of carbon tetrachloride in MeIQx-treated rat liver. Our results indicate that carbon tetrachloride enhances MeIQx hepato-carcinogenicity through increase in oxidative DNA damage but non-effect levels of MeIQx carcinogenic activity still exist.  相似文献   
18.
Esophageal small cell carcinoma (SmC) is considered an aggressive cancer carrying a poor prognosis, although the rarity of this tumor has impeded statistical evaluation. We reviewed records of 457 esophageal cancer patients treated in our department from 1986 to 2000, comparing clinicopathologic factors and post-treatment outcomes, for 9 patients with SmC, most undergoing esophagectomy including lymphadenectomy, with data from 128 patients with esophageal squamous cell carcinoma (SqC) invading to the muscular layer or beyond. Immunohistochemical features were compared between the SmC and 12 consecutive SqC. All patients studied had localized disease according to preoperative staging. SmC showed more ulcerative and infiltrative growth, and more aggressive lymphatic spread, than SqC. All SmC patients had lymph node metastasis (thoracic nodes, 9 patients: abdominal 6; cervical 1). All SmC specimens but no SqC were immunoreactive for neuron-specific enolase. Two and three SmC specimens were reactive for epithelial membrane antigen and keratin, respectively. Survival of SmC patients after esophagectomy (median, 11 months) was worse than for SqC patients (p=0.013). However, 1 SmC patient remains alive at 76 months. Survival was not related to any clinicopathologic or immunohistochemical features. While SmC shows aggressive behavior and worse outcomes than SqC, combining esophagectomy with chemotherapy or radiotherapy may prolong survival.  相似文献   
19.
Human beings are exposed to a multitude of carcinogens in their environment, and most cancers are considered to be chemically induced. Here we examined differences in genetic alterations in rat forestomach tumors induced by repeated exposure to a genotoxic carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) or N-methylnitrosourethane (MNUR), and chronic treatment with a non-genotoxic carcinogen, butylated hydroxyanisole (BHA) or caffeic acid (CA). A total of 132, 6-week-old male F344 rats were employed. Forty rats were treated with MNNG by intragastric administration at a dose of 20 mg/kg body wt once a week for 32 weeks, and 20 rats received 20 p.p.m. MNUR in their drinking water for 48 weeks. Further groups of 20 animals were administered 2% BHA or 2% CA in the diet for 104 weeks. The remaining rats were maintained without any supplement as controls. Multiple forestomach tumors were observed in all rats of the MNNG-, MNUR-, BHA- and CA-treated groups. Histopathologically, MNUR- and CA-treated groups showed almost the same pattern. On polymerase chain reaction-single strand conformation polymorphism analysis, H-ras and p53 gene mutations were observed at high and relatively low frequencies, respectively, in forestomach tumors induced by MNNG and MNUR. Most H-ras gene mutations were G-->A transitions in codons 7 and 12 of exon 1. On the other hand, forestomach tumors due to the non-genotoxic carcinogens, BHA and CA, had almost no mutations of the H-ras and p53 genes. Moreover, relative overexpression of cyclin D1 and p53 was detected in forestomach tumors induced by the genotoxic carcinogens, while their non-genotoxic counterparts had a tendency to show low expression of those molecules. Mutations of the beta-catenin gene were not detected in any group. The present study demonstrates that rat forestomach tumors induced by genotoxic and non-genotoxic carcinogens have different underlying genetic alterations, even if their pathological features are similar.  相似文献   
20.
To clarify the clinical significance of uterine cervical cytology during pregnancy, we analyzed the incidence of cervical cytology and its accuracy. Of the 1,593 pregnant women underwent cervical cytology, the patients with abnormal cytology were followed up and performed histological confirmation on colposcopic biopsy specimen. An incidence of abnormal cytology and cervical neoplasm during pregnancy were 1.63% (26 cases) and 0.82% (13 cases), respectively. The incidence of abnormal cytology in the pregnant women was significantly higher than that (0.9%) in mass-screened, non-pregnant 214,375 women under the age of 45 years (P < 0.001). There was no significant difference of the incidence of cervical neoplasm between in the pregnant women and in mass-screened, non-pregnant women (0.82% vs. 0.46%). The accuracy of cervical cytology during pregnancy was 45.0% and this was not significantly different from that (27.6%) in the mass-screened, non-pregnant women. Since, cervical screening cytology for uterine cervical cancer in the pregnant women as shown in this study, has an equal effectiveness to that in the mass-screened non-pregnant women, routine cervical cytology is highly recommended to performed during pregnancy. In addition, management of pregnant women with abnormal cytology was discussed in this article.  相似文献   
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