Biomedical subjects

J G Chi

Publications and source records attributed to J G Chi.

At least 109 records · Page 6Linked to original sources

PubMed1996

Fibrosing inflammatory pseudotumors involving the skull base: MR and CT manifestations with histopathologic comparison.

PURPOSE: To describe the MR and CT features of fibrosing inflammatory pseudotumors of the skull base region, and to document the MR signal intensity of the lesions with histopathologic comparison. METHODS: We reviewed the MR and CT studies of five patients with pathologically proved fibrosing inflammatory pseudotumor involving the skull base. Unenhanced spin-echo T1- and T2-weighted and contrast-enhanced T1-weighted MR images were obtained at 0.5 T in three patients and at 1.5 T in two patients. MR findings were correlated with histopathologic findings in all five cases, and the enhancement pattern was compared with CT findings in three cases. RESULTS: In three cases, the cavernous sinus was involved unilaterally, with adjacent extracranial infiltrative masses. In one case, both orbits, the cavernous sinuses, and the tentorium were involved with diffuse infiltrative lesions. One patient had an infiltrative nasopharyngeal mass; and in all five patients, MR images showed localized involvement of the skull base, with bone marrow replaced by tumor. The soft-tissue lesions were hypointense on T2-weighted images in all five cases and showed homogeneous contrast enhancement. Histopathologic studies revealed scanty inflammatory cell infiltration with densely fibrotic background in all cases. The hypointensity of the lesions on T2-weighted images seemed to be related to the degree of fibrosis. CONCLUSION: Fibrosing inflammatory pseudotumor shows characteristic MR findings of infiltrative lesion with bone destruction and hypointensity on T2-weighted images. The lack of mobile protons due to the fibrotic background and/or high cellularity of the lesions may be the reason for their hypointensity and weaker enhancement on MR images.

Adult↗

PubMed1995

Morphological study of surgically induced open neural tube defect in old (14 and 21 days) chick embryos.

As an experimental model for the research of open neural tube defect (NTD), the surgical model has several advantages over others, in spite of the fact that the pathogenetic mechanism is not compatible with the human intrauterine events. To make reproducible NTDs by surgery and to compare the surgically induced lesions with the human myeloschisis morphologically, we opened the neural tube for a length of 9-11 somites in Hamburger and Hamilton stage 16-19 chick embryos. Embryos which survived until the late in ovo life (total age 14 and 21 days) showed relatively reproducible open NTDs. Morphologically they are similar to human myeloschisis. This study suggests that the surgical model can be suitable for studies of open NTDs.

Age Factors↗

PubMed1995

Cystic intrapulmonary lymphangioma: HRCT findings.

We report a rare case of cystic intrapulmonary lymphangioma involving the left lung, which presented with pneumothorax and respiratory distress in a 6-month-old infant. Chest radiographs showed a multicystic lesion in the left lung mimicking the features of congenital cystic adenomatoid malformation of the lung. The lesion appeared on high-resolution CT (HRCT) as a multiseptate, air-filled cystic lesion in the left hilar area. Associated HRCT findings were thickening of interlobular septa and bronchovascular bundles in the left lung and the presence of peripheral pulmonary vessels within cystic lesions in the apex of the left lung. HRCT findings correlated well with histopathologic findings. We suggest that these associated findings may be helpful in distinguishing this condition from other cystic lung diseases and that this entity should be included in the differential diagnosis of multicystic lung lesions.

Cystic Adenomatoid Malformation of Lung, Congenita↗

PubMed1995

Expression of tenascin in hamster buccal pouch mucosa during experimental carcinogenesis.

Experimental carcinogenesis by topical application of 7,12-dimethylbenz(a)anthracene (DMBA) in hamster buccal pouch mucosa was evaluated for expression of tenascin, an extracellular matrix glycoprotein expressed at the epithelial-mesenchymal interface during embryonic and fetal development, wound healing and in the stroma of various neoplastic lesions, by using immunohistochemical methods. The buccal pouch mucosa in normal hamsters showed immunoreactive tenascin either as a linear delicate band or without reactivity at the immediate vicinity of the basement membrane. During carcinogenesis, in the second to fourth week of application of DMBA, the hyalinous changes in the submucosal connective tissue had a weak but diffuse immunoreactivity for tenascin. The hyperkeratinised and hyperplastic mucosa following 5 weeks of application of DMBA showed focal areas of enhanced expression in the vicinity of the basement membrane. Subsequently, specimens showing hyperplasia, dysplasia, carcinoma in situ and invasive carcinomas had comparatively more widespread stromal immunoreactivity where the extent of enhanced reactivity positively correlated with the advancing lesion. These results compared with the results of expression in human normal mucosa, leukoplakia and squamous cell carcinoma of the oral cavity (Shrestha et al., Oral Oncol, Eur J Cancer 1994, 30, 132-137) suggest that the expression of tenascin in experimental carcinogenesis of hamster buccal pouch mucosa, as a model, faithfully mimics the same in human oral mucosa.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed1995

An immunohistochemical analysis of mdr-1 and bcl-2 expressions in neuroblastoma.

Among the differentiation-related changes in neuroblastoma are expressions of mdr-1 and bcl-2, which may be potentially related to the resistance to anticancer chemotherapy. In the present study, the authors performed an immunohistochemical analysis of mdr-1 and bcl-2 expressions in 30 neuroblastomas using monoclonal anti-P-glycoprotein(mdr-1 product) antibody and monoclonal anti-bcl-2 antibody to investigate the significance of their expression. The overall incidence of mdr-1 and bcl-2 expressions were 53.3% (16/30) and 93.3% (28/30), respectively. The expressions of mdr-1 and bcl-2 didn't seem to be related to the status of preoperative chemotherapy or stage of disease. The expression of mdr-1 was closely related to the differentiation of tumor cells (p < 0.01), especially to the neuronal differentiation. The bcl-2 expression was so common that it seemed to be indigenous to this neoplasm. The overall findings suggested that the expression of mdr-1 is one of the differentiation markers, while bcl-2 expression may partly explain the reasons for the relatively poor prognosis of neuroblastoma by the resistance to anticancer chemotherapy, which is a major therapeutic tool for this peculiar neoplasm.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1995

Patterns of bcl-2 expression in placenta.

A total of 39 placentas, whose gestational ages ranged from 8 to 41 weeks, were analyzed for bcl-2 expression using immunohistochemistry and immunoblotting. Immunohistochemically, both intracytoplasmic and nuclear expression of bcl-2 was observed in villous and extravillous trophoblasts, villous mesenchymal cells and capillary endothelial cells, villous macrophages, intermediate trophoblasts, amnionic epithelium, and even in decidua and endometrial glandular epithelium in early gestational periods. The degree of expression significantly decreased in the placentas after the gestational period of 32 weeks which coincides with the declining phase of placental increase. On immunoblotting lysates of 10(4) cells from single cell suspensions of fresh placentas, bcl-2 was detected in the placentas of 22 and 33 gestational weeks, but it was negligible or absent in three term placentas. The results of the present study suggest two possible implications on the role of bcl-2 in placenta: 1) it may be a type of proliferation or maturation-related marker, especially of trophoblasts, which show decreased expression along with terminal differentiation and maturation, and 2) because the primary role of bcl-2 is the inhibition of programmed cell death (PCD), the decrease in placental bcl-2 around term may be a parturition-associated biological change.

Female↗

PubMed1995

Expression of transglutaminase C during the prenatal development of human submandibular glands.

The involvement of transglutaminase C (TGase C) in morphogenesis and cytodifferentiation during glandular tubule formation was addressed by immunolocalization of the protein at different stages of prenatal human submandibular gland development in 100 fetuses and 20 adult salivary glands. Immunocytochemical detection was carried out using a monospecific antibody to TGase C. The results showed TGase C reactivity in both acini and ducts early in development (from 10 to 14 weeks), followed by a marked increase in ductal activity and a decline in acinar activity up to 32 weeks. During the peak of reactivity at 25 to 32 weeks, staining was concentrated in the apical ends of the columnar cells. In the adult, staining was weakly and diffusely distributed in the striated and excretory ducts. Western blot analysis of the cellular extracts of pooled samples from various stages of salivary gland development showed a single strong band at 76 kDa early in development. This band became weaker after 32 weeks of prenatal development and in the adult. These findings of transient high expression of TGase C, which coincide with the development of tubulo-alveolar structure, suggest that TGase C may play a role in morphogenesis in human salivary gland development.

Adult↗

PubMed1995

Histologic structure of antrochoanal polyps.

The antrochonanal polyp (ACP) is defined as a maxillary sinus polyp that originates in the maxillary sinus, passes through the sinus ostia, and extends into the choana. The aim of this study was to compare the histologic findings of 40 cases of ACP with those of allergic and non-allergic nasal polyps, and so possibly to elucidate the pathogenesis of ACP. No allergy could be verified in any of the ACP patients. Inflammatory cell infiltration was significantly more severe in the ACP group than in the allergic polyp group. Eosinophilic infiltration was significantly less severe in the ACP group than in the allergic polyp group. Edema was not significantly different between the ACP, allergic, and non-allergic groups. In the ACP group, the presence of submucous glands was significantly less pronounced than in the ordinary nasal polyp groups. The fibrous type was present significantly more often than the infiltrative or granulating type in the ACP group. The histologic findings and clinical features of the ACP indicate that it has little causal relationship with nasal allergy but is all the more intimately associated with inflammatory processes. The paucity of submucous glands suggests that the ACP results from edematous hypertrophy of the respiratory epithelium rather than from distension of the glandular structures.

Adolescent↗

PubMed1995

Malignant intraventricular schwannoma. Case report.

The authors present the clinical, radiological, and pathological features of a malignant schwannoma occurring in the right lateral ventricle of a 40-year-old man. Metastasis to both cerebellopontine angles and to the cerebellum was found 7 months after subtotal removal of the tumor.

Adult↗

PubMed1995

Differential expression of leukocyte common antigen in human fetal lymphoid organs.

To investigate the differential expression of various types of leukocyte common antigen (LCA) isoforms during development, we analyzed human fetal lymphoid organs, including the thymus, liver, spleen, and bone marrow from 14 weeks to 29 weeks of gestational age by immunohistochemical and flow cytometric methods. In fetal thymus, over 90% of thymocytes throughout the entire fetal life expressed CD45RO and CD45RB, while CD45RA was expressed only in less than 5% of thymocytes. This expression pattern of LCA isoforms was established by a gestational age of 14 weeks or earlier, and persisted throughout the fetal period. The tissue distribution was different from each isoform; CD45RO-positive thymocytes were found in both the cortex and medulla at the 14th week with low intensity, but was localized in the cortex with increasing fetal age. CD45RB-positive thymocytes distributed mainly in the medulla from early gestational age. Among extrathymic lymphoid organs, a small portion of lymphoid cells expressing leukocyte common antigens appeared first in the liver at 10-12 weeks of gestational age and was followed by a small number in the spleen and bone marrow by 13-15 weeks. All lymphoid cells in these extrathymic lymphoid organs at this stage were CD19+ B cells. The number of these CD19+ cells increased abruptly during the early period of mid-gestational age. The pattern of tissue distribution of each LCA isoform in the fetal liver and spleen correlated well with the patterns of quantitative analysis by flow cytometry. In summary we found that different LCA isoforms expressed in cell-type-specific pattern and showed different tissue distribution during the period of fetal development, and that LCA was the earliest antigen expressed by lymphocytes in the thymus and extrathymic lymphoid organs in our series.

Bone Marrow↗

PubMed1995

Mansonian schistosomiasis in rectum--report of a case.

Schistosomiasis is a snail-transmitted trematodiasis acquired by immersion in water which contains the cercariae. In Korea, six imported cases of urinary schistosomiasis by Schistosoma haematobium and one case of imported cerebral schistosomiasis by S. mansoni were reported. Herein we report a case of S. mansoni infecting rectum of a 46 year-old Korean male, who had been to Saudi Arabia for two years. On colonoscopy for routine physical check up, a 0.4 cm polyp in the rectum was detected and biopsy was done. Microscopically, rectal mucosa showed several granulomas which were composed of macrophages, lymphocytes, neutrophils and eosinophils. The center of each granuloma showed an ovoid egg often containing miracidium. The eggs measured 130 x 60 microns in average size. They had yellowish-brown transparent shell with the characteristic lateral spine. This is the 8th imported case of schistosomiasis in Korea and the second one infected by S. mansoni.

Animals↗

PubMed1995

Bone pathologic correlation of multimodality imaging in Paget's disease.

The pagetic bones in the active phase of the disease with brisk lysis and sclerosis manifest intense tracer uptake on planar bone and SPECT images. Intense tracer uptake, however, can occur also in infections, dysplasias and metastases. Pinhole bone scintigraphy has been shown to portray specific diagnostic signs in a number of skeletal diseases. In an effort to identify useful bone scan signs, we prospectively carried out 99mTc-oxidronate pinhole bone scintigraphy of the skull, vertebrae, ribs, humerus, sacrum and ilium in two patients with Paget's disease of the bone. The pinhole bone scintigraphy findings correlated with radiographic, CT and MRI findings and in the vertebra with the pathological study. Interestingly enough, pinhole bone scintigraphy revealed intense tracer uptake preferentially in the bone cortex and the rim of the affected bones. Thus, the cranial inner table, humeral cortex and vertebral endplates and rims were the seats of characteristic tracer uptake, respectively creating a scintigraphic version of the radiographic "cotton wool" sign, "casket" sign and "picture frame" sign. The pagetic lesions in the sacrum and ilium also showed intense cortical and rim uptake. Correlation of pinhole bone scintigraphy with radiography, CT and MRI indicated that such cortical or rim uptake is characteristic of Paget's disease.

Bone and Bones↗

PubMed1995

Primary ciliary dyskinesia: ultrastructural defects and clinical features.

Primary ciliary dyskinesia is a genetically determined disorder characterized by immotility or poor motility of the cilia in the airways and elsewhere. Certain specific defects in the ciliary axoneme can be found, which are pathognomonic of the syndrome. The defects include missing dynein arms, abnormally short dynein arms, spokes with no central sheath, missing central microtubules, and displacement of one of the nine peripheral doublets. We have reviewed 19 cases of primary ciliary dyskinesia diagnosed by transmission and scanning electron microscopy. The age distribution ranged from five to 15 years, and there were six males and 13 females. All 19 cases had abnormal cilia which consisted of Ia (three cases), Ib (three cases), isolated Id (three cases), isolated II (one case), isolated III (two cases), and Id + other types (seven cases), according to Sturgess' classification. The most pronounced clinical manifestations are chronic paranasal sinusitis (52%) and chronic bronchiectasis (52%), followed by bronchopneumonia (26%), chronic bronchitis (21%), and nasal polyps (15%).

Adolescent↗

PubMed1994

Macrocystic serous cystadenoma of pancreas--a case report.

The macrocystic variant of serous cystadenomas of the pancreas has only recently been described. We present a case of a 40 year-old female, who presented with vague indigestion. The cyst was unilocular, and was lined by simple cuboidal, ciliated serous type epithelium. Fine needle aspiration, immunohistochemical, light microscopic, and electron microscopic studies are discussed.

Biopsy, Needle↗

PubMed1994

A clinical study of benign focal amyotrophy.

We reviewed the clinical, electrophysiological, radiological, and histopathological findings in 25 patients with benign focal amyotrophy. There were 14 patients with upper limb type and 11 with lower limb type. 18 patients had unilateral involvement and 7 had bilateral involvement asymmetrically. The characteristics clinical features were sporadic occurrence, predominance in young males, nonprogressive course or initial progression for 1 to 3 years followed by stationary state, segmental distribution of muscle weakness and atrophy localized to one limb or both homologous limbs markedly asymmetrically, and absence of any definite sensory loss or central nervous system involvement. The electrophysiological, radiological, and muscle histopathological findings suggested chronic focal anterior horn cell disease. Although the prevalence of this disease is still unknown, the importance of recognition is being emphasized because of its common occurrence in our country and the benign prognosis.

Adolescent↗

PubMed1994

The prognostic significance of c-erbB-2 and p53 protein expressions in gastric carcinoma--a multivariate analysis of prognostic factors.

152 curative gastrectomy specimens from patients with gastric carcinoma were examined in an attempt to assess the prognostic value of c-erbB-2 and mutant p53 protein expressions. The labeled streptavidin-biotin method was applied to routinely fixed and paraffin-embedded tissue sections, using the polyclonal and monoclonal antibodies against the c-erbB-2 protein and the mutant form p53 protein, respectively. In this examination, staining of c-erbB-2 protein was found in 9.2% of these carcinomas. The c-erbB-2 stained tumors were significantly associated with the tumors whose diameters were smaller than 5cm, and were more likely to be associated with serosal invasion and nodal involvement than the unstained ones. However, there was little association between staining of c-erbB-2 protein and clinicopathologic findings such as age, sex, location, histology, gross type, lymph node status, depth of invasion, and stage. The survival analysis of 104 patients with stage III gastric carcinoma revealed no significant association between c-erbB-2 staining status and survival duration. The 5-year survival rates of the c-erbB-2 positive group and its negative group were 21% and 28%, respectively. Positive p53 protein expression was observed in 46% of 152 carcinomas. There was no significant association between p53 expression and parameters such as age, sex, location, histology, gross type, and size. The p53 stained tumors were more likely to be associated with lymph node metastasis, serosal invasion than p53 unstained ones; but this did not reach significance. The 5-year survival rates of the p53 positive group and counter part group were 27% and 31%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Morphology of the cardiovascular system in conjoined twins: spatial and sequential segmental arrangements in 36 cases.

Thirty-six pairs of conjoined twins are reviewed from the joint experience of the authors. The external forms of conjunctions were 18 thoracopagus (joined at chest), eight cephalothoracopagus (joined at head and chest), eight dicephalus (single trunk and two heads), one craniopagus (joined at head), and one omphalopagus (joined at abdomen). There was one case with a single conventional heart in association with isomerism of the left lungs and absence of the heart in the left-side twin. Six cases had two conventional hearts. All of them had associated lesions, which were more severe in three cases (50%) with abnormal laterality. All of the cephalothoracopagus (eight cases) had two shared hearts. Cardiac lesions were commonly seen in the posterior heart, but the arrangement of atrial appendages were normal in every heart. Twenty-one cases of either dicephalus or thoracopagus had a compound heart. Three cases (14%) had fusion only at the level of venous sinus; three others (14%) were fused at the atrial level only, but 15 cases (71%) had fusion at both atrial and ventricular levels. Abnormal laterality was an associated lesion in ten cases (48%) with a compound heart. The fusion at the atrial level always occurred between right atriums, but ventricular fusion was more commonly between two left ventricles. Four atrial or ventricular chambers, if fused, were arranged in a cruciate arrangement. Mode of conjunction was as important, in the formation of the cardiovascular system, as was the degree of fusion. Abnormal laterality, which is commonly associated in lateral or mixed lateral/facing conjunction, was the most important factor affecting the general morphology of the cardiovascular system.

Female↗

PubMed1993

Intracranial mesenchymal chondrosarcoma: a case report and literature review.

Intracranial mesenchymal chondrosarcoma is a rare entity. The case of a 13-year-old girl with mesenchymal chondrosarcoma which seemed to arise from the dura mater is presented here together with a review of the literature. In the present case, the tumor involved the superior sagittal sinus. It recurred 21 months after gross total removal of the mass and coagulation of the involved wall of the superior sagittal sinus. Reoperation was performed followed by radiation therapy.

Adolescent↗