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Biomedical subjects

T T Kuo

Publications and source records attributed to T T Kuo.

At least 19 recordsLinked to original sources

Characterization of an open reading frame involved in site-specific integration of filamentous phage Cf1t from Xanthomonas campestris pv. citri.

Cf1t is a single-stranded DNA filamentous phage; a 1.9-kb segment of DNA from Cf1t was found to be responsible for site-specific integration into Xanthomonas campestris pv. citri (XW47), in the absence of any Xanthomonas origin of replication. Deletion analysis and introduction of amber stop codons into this fragment from Cf1t revealed an open reading frame (ORF344) which was involved in the integration function. The predicted amino-acid sequence of ORF344 bears no homology with conserved sequences of the integrase family.

Amino Acid Sequence

Absence of p53 gene mutation and infrequent overexpression of p53 protein in hepatoblastoma.

Ten cases of hepatoblastoma were studied for overexpression of p53 protein by immunohistochemistry and for possible p53 gene mutation by single strand conformation polymorphism (SSCP) analysis and direct DNA sequencing of the polymerase chain reaction products. Only one case of the macrotrabecular type at stage IV showed overexpression of p53 protein. No DNA mobility shift was found in any of these cases studied by SSCP analysis. DNA sequencing performed on the case showing overexpression of p53 protein revealed no mutation within exons 5 to 8. The associated adrenal cortical carcinoma of the same case also showed overexpression of p53 protein, but no mutation of the p53 gene. These results indicate that mutation of the p53 gene is infrequent in hepatoblastoma. This observation supports the view that mutation of the p53 gene is not as important in the oncogenesis of childhood neoplasms as in adult cancers.

Base Sequence

Abnormal growth induced by expression of HBsAg in the secretion pathway of S. cerevisiae pep4 mutants.

The toxicity of HBsAg in the secretion pathway of pep4 strains can be progressively reduced in modified SD media containing lower concentrations of ammonium sulphate. A procedure, combining a reduction of ammonium sulphate concentration in SD media with the disruption of the PEP4 gene of the host strain, was developed to enrich transformants which are not inhibited by HBsAg expressed in the secretion pathway. Abnormal growth of these non-inhibited transformants is characterized by the enlargement of cell morphology, a transition to pseudohyphal-like growth in nitrogen-starved media, an increase in HBsAg particle production, and the enhancement of growth rate in liquid media. This suggests a new approach to overcoming the toxicity of heterologous protein in the yeast secretion pathway.

Amino Acid Sequence

Clear cell papulosis: report of three cases of a newly recognized disease.

BACKGROUND: Clear cell papulosis is a newly described disease. Since the first report in 1987, no other cases have been reported. OBJECTIVE: Our purpose was to describe three more newly identified cases that further characterize this disease. METHODS: Formalin-fixed and paraffin-embedded biopsy specimens were used for histochemical and immunohistochemical studies. RESULTS: The three patients included two boys and, for the first time, a girl. All three had multiple white papules on the lower part of the abdomen, with or without scattered lesions along the milk lines bilaterally. The main histopathologic finding was the presence of clear cells scattered mainly among the basal cells of the acanthotic epidermis. The clear cells were variably stained by mucicarmine, colloidal iron, alcian blue (pH 2.5), periodic acid-Schiff, the anticytokeratin antibody AE1, carcinoembryonic antigen, epithelial membrane antigen, and gross cystic disease fluid protein-15. CONCLUSION: Clear cell papulosis is a unique clinicopathologic entity. The clear cells were confirmed to be sweat gland secretory cells by their positive immunostaining with gross cystic disease fluid protein-15. The latter was also present in eccrine sweat gland coil cells. However, whether the clear cells were eccrine or apocrine secretory cells could not be determined.

Biopsy

Kikuchi's disease (histiocytic necrotizing lymphadenitis). A clinicopathologic study of 79 cases with an analysis of histologic subtypes, immunohistology, and DNA ploidy.

We conducted a clinicopathologic study of 79 cases of Kikuchi's disease. Our results confirmed that Kikuchi's disease is a distinctive type of necrotizing lymphadenitis that affects primarily the cervical lymph nodes of young adults and has a self-limited clinical course. However, female predominance was not as striking as heretofore reported. A low, but possible, recurrence rate of 3.3% was documented. Extranodal cutaneous involvement occurred in one patient who had a more severe and protracted clinical course. Classification of the histopathologic changes into three histologic types was proposed: proliferative, necrotizing, and xanthomatous types. These three types differed in certain aspects of their clinical features. Immunohistologic analysis revealed that the predominant cells of the lesions were various types of histiocytes, including the enigmatic plasmacytoid monocytes. A variable number of CD8(+) T cells correlating with the duration of the disease was detected. B cells were nearly absent, and only an insignificant number of OPD4(+) T cells was present. Eight cases studied by the flow cytometric DNA analysis all showed a diploid DNA content. Although the histologic changes of Kikuchi's disease were variable, the findings were sufficiently distinctive to permit accurate diagnosis. Malignant lymphoma and especially lupus lymphadenitis can be mistaken for Kikuchi's disease; thus differentiation is crucial.

Adolescent

Prolongation of intraventricular conduction time associated with fatal [correction of fetal] impairment of defibrillation efficiency during treatment with class I antiarrhythmic agents.

To test whether fatal deterioration of defibrillation efficiency during antiarrhythmic therapy can be prevented by avoiding extreme decrease in ventricular prevented by avoiding extreme decrease in ventricular conduction or toxic plasma drug levels, we determined the defibrillation threshold (DFT) before and during infusion of incremental doses of disopyramide (n = 8), mexiletine (n = 9), or flecainide (n = 9) in anesthetized dogs. Disopyramide did not alter DFT [from 4.4 +/- 1.5 to 4.4 +/- 1.6 J (3.1 +/- 1.2 micrograms/ml)]. Mexiletine tended to increase DFT [from 4.6 +/- 1.2 to 6.1 +/- 2.0 J (1.8 +/- 0.6 micrograms/ml); p < 0.05], and defibrillation eventually was unsuccessful in 3 of the 9 dogs. Although the plasma mexiletine level before refractory fibrillation was far beyond the human therapeutic range, prolongation of intraventricular conduction time (CT) was moderate (16 +/- 3%). Flecainide increased DFT from 4.2 +/- 1.3 to 6.1 +/- 1.5 J at a plasma level of 1.04 +/- 0.37 micrograms/ml (p < 0.0005). In 3 of 5 dogs that developed refractory fibrillation, plasma flecainide level before terminal ventricular fibrillation (VF) was not toxic, but prolongation of CT in the 5 dogs was remarkable (30 +/- 9%). Thus, VF resistant to defibrillation is not necessarily associated with both toxic plasma drug level and remarkably decreased conduction. Reliability of these valuables as indicators of fatally deteriorated defibrillation efficiency may vary among antiarrhythmic agents.

Analysis of Variance

Paget's disease.

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Adolescent

Kimura's disease and angiolymphoid hyperplasia with eosinophilia: new observations from immunohistochemical studies of lymphocyte markers, endothelial antigens, and granulocyte proteins.

Kimura's disease (KD) typically presents as large subcutaneous masses in young Oriental males. It is characterized by deep inflammation with vascular proliferation, lymphocytic nodules with subcutaneous germinal centers, fibrosis, and edema. In comparison, angiolymphoid hyperplasia with eosinophilia (AHLE) occurs in all races and the lesions usually are smaller and more superficial. The causes of these two diseases are debated. We compared histologic features of 4 cases of KD with 22 cases of ALHE and studied expression of endothelial antigens and lymphocyte markers as well as localization of eosinophil, mast cell, and neutrophil granule proteins in lesional tissue. T-cell lymphoid aggregates with well-formed B-cell germinal centers occurred in KD, and nodular and diffuse T-cell infiltration with small B-cell clusters occurred in ALHE. Endothelial proliferation was more pronounced in KD, lacking the atypical histiocytoid endothelial cells characteristic of ALHE. Many intact eosinophils infiltrated lesions in both diseases, although KD had less extracellular granule protein deposition than ALHE. Intact mast cells were seen in both diseases. There was neutrophil elastase staining of occasional scattered intact cells but no extracellular deposition. Compared with KD, ALHE is more varied in its clinical, histopathologic, and immunohistochemical features.

Adult

Specific protein phosphorylation induced in Xanthomonas campestris pv. oryzae by bacteriophage Xp12.

We have investigated the endogenous phosphorylation patterns of phosphorylated proteins of Xanthomonas campestris pv. oryzae induced by its bacteriophages. For bacteriophage Xp12-infected cells, at least three phosphoproteins with apparent molecular weights of 28, 28.5 and 45 kDa were detected by in vitro labeling with [gamma-32P]-ATP. These Xp12-specific phosphoproteins only occurred with Xp12 infection, and were not shown in uninfected or Xp10-infected cells. The protein kinase(s) responsible could use either ATP or GTP as the nucleotide substrate with nearly the same efficiency. Magnesium was proved to be an essential factor for the phosphorylation. EGTA treatment excluding the possibility that the presumed protein kinase was calcium-dependent. Under our reaction conditions, the optimal phosphorylation occurred at pH 7 to 8, for 30 to 40 min at 25 to 37 degrees C. The Xp12-specific protein phosphorylation hint the existence of a physiological regulation mechanism involved in the life cycle of bacteriophage Xp12. Furthermore, the presumed protein kinase was shown to be encoded by the genome of Xp12 rather than indirectly induced by Xp12 infection.

Adenosine Triphosphate

A long lytic cycle in filamentous phage Cf1tv infecting Xanthomonas campestris pv. citri.

In this study the lytic cycle of a filamentous phage is reported. Under normal laboratory cultivation conditions a virulent form could spontaneously and easily arise from a temperate phage. The virulent one could superinfect cells containing Cf1t lysogen. Therefore, we have named it Cf1tv. In a colony formation assay using cells from an infected culture, two types of colonies were observed, small and large. It could be proven that the formation of small colonies is the result of killing during Cf1tv infection. The number of small colony forming units (cfu) increased with infection time and reached a maximum at 16 h after infection, then dropped to the initial cell concentration at 28 h after infection; 28 h were required to kill all infected cells. Large colonies contained uninfected or phage-resistant cells, but no lysogenic cells. Bacterial death was further confirmed by a microculture assay. At 2 h after infection, normal-dividing cells (cfu giving large colonies) contained about 40% of Cf1tv-infected cells, then the percentage decreased with infection time. Slow-dividing cells (infected cfu giving small colonies) initially contained 55% of cells; this percentage increased slightly at 4 h after infection, then decreased at 8 h after infection. Non-dividing cells initially contained 5% of infected cells, then their numbers rapidly increased with time after infection. The cell division was seriously affected and finally stopped. During one-step growth, the latent period was 30 min and there was no burst; phages were released at 30 min after infection and the rate of release increased gradually with time after infection. Phage DNA integration into host chromosome could not be observed.

Bacteriophages

Carcinoid tumor of the thymus with divergent sarcomatoid differentiation: report of a case with histogenetic consideration.

An anterior mediastinal tumor resected from a 54-year-old man without paraneoplastic symptoms was found to be an unusual biphasic thymic tumor composed of carcinoid tumor in sarcomatous stroma characterized by fibrosarcoma-like spindle cells with areas of chondroid and osseous differentiation. Immunohistochemical and ultrastructural studies verified that the tumor described was a carcinoid tumor with divergent sarcomatoid differentiation rather than a mixed carcinoid tumor and sarcoma. The chondroid and osseous differentiations observed were unique features. This tumor is rare and provides an opportunity for understanding tumors with divergent components. The sarcomatoid transformation of thymic carcinoid tumor might denote highly malignant clinical behavior as illustrated by this case.

Adrenocorticotropic Hormone

Cutaneous manifestations of non-01 Vibrio cholerae septicemia with gastroenteritis and meningitis.

A 58-year-old man with diabetes had fever and chills 5 days after ingestion of raw seafood. Nausea, vomiting, watery diarrhea, bilateral calf pain, and neck stiffness subsequently developed. Generalized edema and ecchymotic patches with a vesiculobullous eruption appeared on the extremities. Four blood cultures were positive for Vibrio cholerae non-01. The patient was successfully treated with antibiotics. This is the first documented case of V. cholerae non-01 septicemia with cutaneous lesions and meningitis in Taiwan.

Bacteremia

Ossifying dermatofibroma with osteoclast-like giant cells.

Dermatofibroma or cutaneous fibrous histiocytoma is a common cutaneous tumor. Rare histologic variants have been described. We report another variant of dermatofibroma characterized by osteoclast-like giant cells with metaplastic bone formation. Clinically the lesion was a small, brown, hard papule of several months' duration on the left anterior leg of a 58-year-old woman.

Female

Attenuation of antifibrillatory effects of lidocaine by its metabolite, glycylxylidide: application of modulated receptor hypothesis.

Lidocaine, one of the drugs effective in treating ventricular arrhythmias in acute myocardial infarction (AMI), sometimes loses its efficacy after prolonged administration, possibly owing to the counteraction of glycylxylidide, one of the metabolites of lidocaine, through modulation of binding of lidocaine to sodium channels. To determine whether glycylxylidide interferes with the antiarrhythmic action of lidocaine, we compared the antifibrillatory effects of lidocaine, glycylxylidide, and their combination in 14 anesthetized open-chest dogs. Although glycylxylidide alone prolonged intraventricular conduction time (CT) and did not affect ventricular effective refractory period (VERP), it had different effects when added to lidocaine; i.e., it had no effect on intraventricular conduction time but shortened VERP. Although glycylxylidide alone did not change ventricular fibrillation threshold (VFT), the increase in VFT induced by lidocaine was decreased by addition of glycylxylidide, possibly as a result of competition for the same cardiac sodium channels between lidocaine and glycylxylidide with similar onset but different offset kinetics, which may explain, at least in part, the drug-resistance phenomena that ensue from prolonged lidocaine administration.

Animals

Anticentromere antibodies (ACA): clinical distribution and disease specificity.

Sera from 3528 patients with autoimmune disease, and non-autoimmune disease, and 500 normal individuals were studied for the presence of anticentromere antibodies (ACA) by indirect immunofluorescence on HEP-2 cells. Sixty-seven specimens were identified showing discrete speckled staining: 55 (82.1%), 11 (16.4%), and one (1.5%), were from patients with autoimmune disease, non-autoimmune disease and normal control subjects, respectively. These ACA were present frequently in CREST syndrome (55%), Raynaud's disease (29.6%) and primary biliary cirrhosis (30%). Only 16.4% of the antibody positive patients carried a clinical diagnosis of CREST, which means that ACA are not specific for CREST syndrome. High antibody titre persisted irrespective of whether or not the patients had active disease. The ACA were present infrequently in Sjögren's syndrome, systemic lupus erythematosus, rheumatoid arthritis, immune thrombocytopenic purpura, Graves' disease, immune haemolytic anaemia, and vitiligo. Sera from 107 patients with various other autoimmune diseases were negative for ACA.

Autoantibodies

Sweet's syndrome: clinicopathologic study of eleven cases.

BACKGROUND: The clinicopathologic manifestations of Sweet's syndrome associated with malignancy have been rarely studied in a large series. METHODS: We describe the clinical features of Sweet's syndrome in 11 patients seen during the past 12 years. Histopathologic findings of these patients are discussed. The clinicopathologic manifestations of 249 cases of Sweet's syndrome reported in the literature were reviewed. RESULTS: The clinicopathologic manifestations of Sweet's syndrome associated with hematologic disorders (HSS) were more severe and characterized by bullous pyoderma with more pronounced epidermal changes and ulceration, anemia, giant platelets and abnormal platelet counts. Approximately 40% of the Sweet's syndrome reported in the literature were associated with hematologic malignancy, and the other 7% of patients had solid tumors. CONCLUSIONS: Sweet's syndrome can be classified into three types: (1) association with hematologic disorders (HSS); (2) association with solid tumors (SSS); and (3) idiopathic or associated with various other disorders (ISS).

Adenocarcinoma, Follicular

Immunohistochemical analysis of dermal mononuclear cell infiltrates in cutaneous lupus erythematosus, polymorphous light eruption, lymphocytic infiltration of Jessner, and cutaneous lymphoid hyperplasia: a comparative differential study.

Cutaneous lupus erythematosus (LE), polymorphous light-eruption (PMLE), lymphocytic infiltration of Jessner (LIJ), and cutaneous lymphoid hyperplasia (CLH) are often difficult to differentiate from one another by light microscopic examination. We conducted an immunohistochemical analysis of the mononuclear cell infiltrates in 13 LE, 12 PMLE, 10 LIJ, and 13 CLH with various antibodies. Antibodies L26, UCHL1, and S100 achieved statistically significant differences among the four diseases, but because of the overlaps in the number of UCHL1(+) T cells and S100 protein (+) cells in individual cases, these two antibodies were not useful. Only CLH could be distinguished from LE, PMLE, and LIJ by a greater number of CD20(+) B cells. The latter three conditions could not be differentiated. Contrary to previous reports, plasmacytoid-monocytes were not found to be increased in LIJ for the differentiation of the latter from LE and PMLE. Our results support the conclusion that CLH is a reactive lymphoid hyperplastic process with proliferation of both B and T cells, whereas the T cell was the predominant cell type in the infiltrates of LE, PMLE, and LIJ, indicating that they were related to T cell disorders. The histiocyte was only a minor component cell. The plasmacytoid monocyte in general was not significantly present in all four conditions, but relatively more plasmacytoid monocytes were present in CLH.

Analysis of Variance