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T Yao

Publications and source records attributed to T Yao.

At least 19 recordsLinked to original sources
PubMed1998

Differential effect of B lymphocyte-induced maturation protein (Blimp-1) expression on cell fate during B cell development.

The B lymphocyte-induced maturation protein (Blimp-1) upregulates the expression of syndecan-1 and J chain and represses that of c-myc. We have transfected Blimp-1 into two sublines of the BCL1 B cell lymphoma that represent distinct stages of B cell development in secondary lymphoid tissues. After interleukin (IL)-2 and IL-5 stimulation, the BCL1 3B3 cells differentiate into centrocyte-like cells, whereas the BCL1 5B1b cells blast and appear to be blocked at the centroblast stage. This blasting effect and the increase in IgM secretion that follows it can be blocked by a dominant negative form of Blimp-1. At the same time, the ectopic expression of Blimp-1 in these partially activated cells induces an apoptotic response that also can be suppressed by the same dominant negative protein. A similar effect was noticed when Blimp-1 was expressed in the mature L10A and the immature WEHI-231 lines, indicating this may be a general effect at earlier stages of the B cell development, and distinct from the ability of Blimp-1 to induce maturation in late stages of differentiation. Truncation mutants indicate that the induction of the apoptotic response relies mainly on 69 amino acids within Blimp-1's proline-rich domain. We propose that Blimp-1 expression defines a checkpoint beyond which fully activated B cells proceed to the plasma cell stage, whereas immature and partially activated cells are eliminated at this point.

Apoptosis↗
PubMed1998

Amperometric biosensor with a composite membrane of sol-gel derived enzyme film and electrochemically generated poly(1,2-diaminobenzene) film.

A sol-gel silicate-based biosensor for glucose was made by utilizing a composite membrane of sol-gel enzyme film and electrochemically generated poly(1,2-diaminobenzene) film to improve the selectivity of the sol-gel enzyme sensors. The stability of the sensor was improved by exposing the enzyme layer to glutaraldehyde vapor. The glucose sensor responded rapidly (ca. 15 s) to glucose at 0.6 V (versus Ag/AgCl), without any interferences from electroactive species such as L-ascorbate and urate below 0.2 mM. Reliable results were obtained in the assays of glucose in controlled human sera, with both the steady-state and flow-injection measurements. Subsequently, the same sol-gel procedure was applied to the preparation of the sensors for galactose and cholesterol. The galactose and cholesterol sensors responded rapidly to galactose and cholesterol, respectively, although the sensitivity of these sensors was inferior to that of glucose sensor.

Biocompatible Materials↗
PubMed1998

A father and son with Turcot's syndrome: evidence for autosomal dominant inheritance: report of two cases.

Typical Turcot's syndrome is characterized by the association of a brain glioma together with multiple colonic polyposis, in which the number of polypoid lesions is small and the association of colonic cancer occurs at a younger age than in familial adenomatous polyposis. We describe a family in which both the father and his son presented with typical Turcot's syndrome without parental consanguinity. This is the first report of a family that is considered to follow an autosomal dominant inheritance. After reviewing 25 documented cases in which the average age of death was 20.3 years old, it was learned that the major cause of death was brain tumor (76 percent) and the minor cause was colon cancer (16 percent). Patients were very young and, therefore, unlikely to have produced a child before their death. These facts seem to support the theory that Turcot's syndrome is an autosomal dominant disorder.

Adenomatous Polyposis Coli↗
PubMed1998

Double-contrast radiographic assessment of lupus-associated enteropathy.

PURPOSE: To describe the double-contrast radiographic features of lupus-associated enteropathy. MATERIALS AND METHODS: Six patients with systemic lupus erythematosus involving the small bowel were assessed by double-contrast radiography of the duodenum and small intestine, with reference to clinical manifestations and jejunoscopic findings. RESULTS: Lupus-associated enteropathy could be categorized into two types: acute onset enteritis in four patients and protein-losing enteropathy with hyperlipidaemia in two patients. The former group presented with irregular thickening and spiculation in the folds of the multiple segments of the duodenum to the terminal ileum, and they were frequently accompanied by thumbprinting, suggestive of ischaemic change. The latter group was characterized by mildly thickened folds with multiple submucosal nodules in the upper portion of the jejunum. In one patient from this group, jejunal biopsy demonstrated lymphangiectasia. Both groups were successfully treated by high-dose prednisolone. Follow-up radiography in the former group showed a complete improvement within 2-7 weeks, whereas radiographic abnormalities in the latter remained even after 2 months. CONCLUSIONS: Lupus-associated enteropathy cases may be divisible into two types; an acute ischaemic enteritis type and a protein-losing enteropathy type, each presenting distinct radiographic features.

Acute Disease↗
PubMed1998

B-cell monoclonality precedes the development of gastric MALT lymphoma in Helicobacter pylori-associated chronic gastritis.

Little is known about the temporal changes in Helicobacter pylori density and B-cell clonality during the evolution from chronic gastritis to gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Biopsied specimens from 28 patients with chronic gastritis who developed gastric MALT lymphoma (group A) and from 24 similar patients who did not (group B) during an equivalent follow-up period (mean, 42 months) were retrospectively scored for histological features of MALT lymphoma (0 to 5) and H. pylori density (0 to 3). B-cell clonality was analyzed by polymerase chain reaction (PCR). During the observation period, the H. pylori density in group A decreased significantly in comparison with group B; the mean change in H. pylori density (final minus initial density) per 1000 days was -1.4 for group A and +0.2 for group B (P < 0.005). Monoclonality was detected more frequently in group A (79%) than in group B (21%; P < 0.005), and it preceded the histological evidence of malignant transformation in 64% of those patients who showed monoclonality in group A. These results suggest that H. pylori is thus more closely associated with the precursor or initial phase in the genesis of gastric MALT lymphoma than with the later phase, as its density decreases as the tumor progresses. The detection of B-cell monoclonality by PCR is thus of possible use for predicting the histological genesis of gastric lymphoma.

Adolescent↗
PubMed1998

[Long-term clinical course and prognosis of patients with Crohn's disease].

The aim of the present study is to clarify long-term clinical course, prognosis and factors influencing prognosis of patients with Crohn's disease suffering for more than 10 years. Sixty-eight patients (47 males, 21 females) with Crohn's disease in whom the clinical course could observed well at our hospital for more than 10 years were studied. We classified these patients into three groups (good, fair, bad) according to their changes of IOIBD assessment score. And we compaired some clinical factors in these groups to clarify factors influencing prognosis. The results were as follows: 1) Twelve patients (18%) were in good prognosis group, and 24 patients (35%) in fair one, and 32 patients (47%) in bad one. 2) IOIBD assessment score at the time of diagnosis, site of leision, and radiographic findings at the time of diagnosis showed significant difference between bad prognosis group and the other two groups. Although there have been many reports that Crohn's disease is generally progressive, our results indicated that more than half of the patients showed favorable prognosis during the follow-up period for more than ten years.

Adult↗
PubMed1998

[Inflammatory bowel disease--Crohn's disease].

Acute massive hemorrhage from CD occurred in 3.0% in our institution. Forty CD patients with massive hemorrhage were reported in last 20 years in Japan. The ratio of male to female was 7.0. Ninety percent of them complicated the small intestinal CD. Massive bleeding was seen mostly in the ileum (82.5%) and next was in the colon (12.5%). However massive gastrointestinal hemorrhage is not often complicated in Crohn's disease, acute massive hemorrhage is occasionally critical. Therefore it is considered that CD should be treated carefully.

Acute Disease↗
PubMed1997

Synchronous and metachronous primary gastric lymphoma and adenocarcinoma: a clinicopathological study of 12 patients.

BACKGROUND: The occurrence of both malignant gastric lymphoma and adenocarcinoma in the same patient is very rare. METHODS: The resected specimens from 12 patients who had both primary gastric lymphoma and adenocarcinoma were analyzed using immunohistochemistry and in situ hybridization. RESULTS: Two different tumors were found synchronously in 10 patients (5 with independent tumors and 5 with contiguous/collision tumors) and metachronously in 2. The size of the lymphomas (mean, 7.2 cm) was larger than that of the adenocarcinomas (mean, 3.6 cm) (P < 0.005). Histologically, 9 of the 12 lymphomas (75%) were mucosa-associated lymphoid tissue lymphomas, and all lymphomas invaded the deep portion of the submucosa or deeper. Conversely, 10 of the 12 adenocarcinomas (83%) were early carcinomas. Six adenocarcinomas were intestinal type, whereas the other 6 were diffuse type. The MIB-1 index of the adenocarcinomas (mean, 50.4%) was higher than that of the lymphomas (mean, 29.3%) (P < 0.05). Helicobacter pylori (H. pylori) was documented in all 12 patients, whereas Epstein-Barr virus-encoded RNA 1 was detected in only 2. During the follow-up period after surgery, 6 patients died, 4 due to adenocarcinoma. The survival probability of all 12 patients appeared to be similar to that of previously reported patients with gastric adenocarcinoma alone, and was significantly worse than that of the 217 patients with gastric lymphoma alone (P < 0.05). CONCLUSIONS: An H. pylori infection is considered to be associated with the development of these double malignancies. In many such synchronously observed cases, lymphomas may precede carcinogenesis, while the prognosis appears to be more closely associated with the adenocarcinoma than the lymphoma.

Adenocarcinoma↗
PubMed1997

Helicobacter pylori and primary gastric lymphoma. A histopathologic and immunohistochemical analysis of 237 patients.

BACKGROUND: Few previous articles have analyzed the relation between infection with Helicobacter pylori (H. pylori) and primary gastric lymphoma in a large number of patients. METHODS: Resected and biopsied specimens from 237 patients with primary gastric lymphoma were investigated for H. pylori using hematoxylin and eosin stain, modified Giemsa stain, and immunohistochemistry. These specimens were compared with specimens from 29 patients with chronic active gastritis, 33 with peptic ulcers, and 41 with gastric carcinoma. RESULTS: H. pylori was detected in 145 of 237 patients (61%) with gastric lymphoma. The frequency of H. pylori positivity was higher in patients with lymphoma restricted to the mucosa and submucosa (76%) than in those with lymphoma invading beyond the submucosa (48%) (P < 0.001), and was also higher in patients with low grade mucosa-associated lymphoid tissue lymphoma (72%) than in those with high grade tumors (55%) (P < 0.05). The frequency of H. pylori positivity in patients with lymphoma was lower than in those with chronic active gastritis (100%) (P < 0.001) or peptic ulcer (91%) (P < 0.05). In patients with lymphoma restricted to the mucosa and the superficial portion of the submucosa, the frequency of H. pylori positivity (90%) was as high as that observed in patients with chronic active gastritis and peptic ulcer. The H. pylori grading score for patients with lymphoma (0.9 +/- 1.0) was lower than for those with chronic active gastritis (1.9 +/- 0.8) (P < 0.001), peptic ulcers (2.2 +/- 1.0) (P < 0.001), or gastric carcinoma (1.2 +/- 1.1) (P < 0.05). CONCLUSIONS: These results suggest that H. pylori is more likely to be associated with early states of primary gastric lymphoma than with advanced states. Thus, H. pylori may disappear during the progression of primary gastric lymphoma.

Adolescent↗
PubMed1997

Thyroid neoplasia and familial adenomatous polyposis/Gardner's syndrome.

This study was conducted to clarify the actual morbidity and clinicopathologic features of thyroid neoplasia in patients with familial adenomatous polyposis. We analyzed the clinical records of 49 Japanese patients with familial adenomatous polyposis diagnosed at our institute. Six of these patients had thyroid neoplasias (3 carcinomas, 2 adenomas, and 1 of unknown histology). Among 17 patients (11 men and 6 women) who had been examined by thyroid ultrasonography or in whom postmortem examination was performed; we categorized 6 patients with thyroid tumor as the TT group, and the remaining 11 without thyroid tumor as the NTT group. The clinical features of the two groups were compared. Thyroid neoplasia was detected by physical examination in 2.3% of 43 patients so examined and was detected in 25% of 8 patients examined by thyroid ultrasonography, and in 44% of the 9 patients subjected to postmortem examination. There were no significant differences between the TT and NTT groups in gender; age at first admission, colectomy, and last follow-up visit; number of colonic polyps; or in presence of colorectal cancers, gastroduodenal adenomas, gastric fundic gland polyposis, retinal pigmented lesions, or extraintestinal tumors. The thyroid gland is frequently affected in patients with familial adenomatous polyposis, but there may be no association between thyroid neoplasia and other clinical manifestations.

Adenomatous Polyposis Coli↗
PubMed1997

Improved prognosis of solid-type poorly differentiated colorectal adenocarcinoma: a clinicopathological and immunohistochemical study.

AIMS: We rarely encounter solid-type poorly differentiated colorectal carcinoma, and their histogenesis and biological behaviour are not fully disclosed. METHODS AND RESULTS: A review of 60 poorly differentiated carcinomas of the colorectum was undertaken, 36 (59%) of which were located in the right side of the colorectum. Although, on the basis of the World Health Organization (WHO) classification solid carcinomas are included among undifferentiated carcinomas, the poorly differentiated carcinomas were divided into four types; 27 solid carcinomas (Sol.), 17 poorly differentiated adenocarcinomas (PDA), six signet-ring cell carcinomas (Sig,) and 10 mucinous carcinomas (Muc.). Solid carcinomas revealed a solid alveolar growth of fairly uniformly sized tumour cells with occasional mitotic figures. This type of tumour had a relatively lower percentage of lymphatic permeation and lymph node metastasis compared with the other three types. The 5-year survival rates were 31% for all poorly differentiated carcinomas, 47% for the Sol. type, 32% for the PDA type, and 0% for both the Sig. and the Muc. types, with a rate of 72% for well-differentiated adenocarcinomas selected as controls. Immunohistochemically, bcl-2 protein expression was demonstrated in 38% of the Sol. type, but in only 12% of the other three non-solid types, this difference being significant (P < 0.05). CONCLUSIONS: These findings suggest that solid carcinomas of the colorectum should be regarded as a distinct type of poorly differentiated carcinoma, leading to a good prognosis.

Adenocarcinoma↗