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K W Min

Publications and source records attributed to K W Min.

At least 55 records · Page 3Linked to original sources
PubMed1993

Alterations in phenotypic biochemical markers in bladder epithelium during tumorigenesis.

Phenotypic biochemical markers of oncogenesis and differentiation were mapped in bladder biopsies to investigate changes that occur in bladder tumorigenesis and to identify markers for increased bladder cancer risk. Touch preparations from biopsy specimens from 30 patients were obtained from tumors, the adjacent bladder epithelium, and random distant bladder epithelium. Markers, including DNA ploidy, epidermal growth factor receptor (EGFR), and oncoproteins, were quantified in individual cells by using quantitative fluorescence image analysis. Cluster analysis revealed the markers fell into three independent groups: (i) G-actin and EGFR; (ii) ploidy, cytology, and p185 (HER-2/neu oncoprotein) (ERBB2); and (iii) p300, a low-grade tumor antigen. Each marker displayed a gradient of abnormality from distant field to adjacent field to tumor. Different patterns for each marker suggested a developmental sequence of bladder cancer oncogenesis; G-actin was altered in 58% of distant biopsies (vs. 0/6 normals, P < 0.001), ploidy and cytology were altered in < 20% of distant fields and approximately 80% of tumors, and the other markers were intermediate. Patterns of EGFR and p185 suggest low-and high-grade tracks diverge early (P < 0.05 by Mann-Whitney U test for EGFR and ANOVA for p185). In conclusion, this study shows that a sequence of phenotypic changes accompanies development and progression of bladder cancers. Biochemical alterations in cells of the bladder field are often detectable before abnormal pathology, and markers previously thought to be limited to tumors were found in the field. The hierarchy of expression may be useful in identifying high-risk patients, assessing completeness of response to therapy, and monitoring and predicting recurrence.

Analysis of Variance↗
PubMed1993

Field molecular epidemiology. Feasibility of monitoring for the malignant bladder cell phenotype in a benzidine-exposed occupational cohort.

Modern molecular and cellular biology have provided powerful new approaches to study cancer in the research laboratory, but these techniques have not been used extensively in field studies or in screening of high-risk occupational cohorts. The primary objective of this study was to demonstrate the use of cellular and molecular methods in combination with medical and epidemiologic methods to identify cancer cases, risk factors, and markers in a previously identified and defined cohort of Chinese workers exposed to benzidine. The screening of exposed workers included occupational, medical, and smoking histories to identify exogenous risk factors, a limited physical examination, Papanicolaou (PAP) urinary cytology, measurement of urine pH, quantitative fluorescence image analysis (QFIA) cytology to detect DNA hyperploidy, and quantitative fluorescence to detect expression of a low-grade bladder tumor-associated antigen (p300) by exfoliated urothelial cells and elevated expression of the neu oncogene product (p185). Detailed analysis of the accuracy of epidemiologic data and the adequacy of samples and accuracy of molecular techniques was carried out. Three groups were included in this study: group 1 included 23 bladder cancer cases who had previously been exposed to benzidine and served as two surrogates for late-emerging disease; group 2 consisted of 20 subjects with previous exposure history but not previously diagnosed with bladder cancer; and group 0 was the nonexposure and nonbladder cancer controls. The results showed that accurate questionnaire data and urine samples can be obtained at remote sites. Among the 20 group 2 subjects, two displayed abnormal findings by both QFIA cytology and p300 expression and were later confirmed to have bladder cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Benzidines↗
PubMed1992

Renal thrombotic microangiopathy in patients with systemic lupus erythematosus and the antiphospholipid syndrome.

Current studies indicate that a thrombotic microangiopathy (TMA) identifies patients with systemic lupus erythematosus (SLE) who are at high risk of progressing to end-stage renal disease. We have observed two patients with SLE and one patient with a primary antiphospholipid syndrome (APS) who developed acute renal insufficiency with thrombocytopenia. Renal biopsies showed a TMA characterized by thrombi or by cellular and mucoid intimal hyperplasia of small arteries and arterioles. No arterial or arteriolar immune-complex deposits were detected by immunofluorescent or electron microscopy. Biopsies from one SLE patient and the APS patient showed no immune-complex glomerular disease. Both had serum antiphospholipid antibodies (aPL). aPL were not detected in the serum of the other SLE patient who had an active lupus nephritis. Acute renal failure and thrombocytopenia resolved in each case following treatment by plasmapheresis or prednisone and heparin. None of the patients were initially treated with cytotoxic drugs. As more knowledge is gained, the accurate identification of renal vascular lesions in SLE or related diseases could influence renal prognosis and choice of therapy. The cases reported here provide further evidence that a TMA can cause acute renal failure independent of lupus nephritis. TMA should be distinguished from other forms of renal vascular disease, particularly a noninflammatory lupus microangiopathy, which is probably mediated by subendothelial immune-complex deposits. The absence of immunoglobulin deposits in vessels involved by a TMA indicates that microvascular thrombosis is promoted by mechanisms other than those usually attributed to immune-complex disease. Phospholipid reactive antibodies may be pathogenetic in some cases.

Acute Kidney Injury↗
PubMed1992

Small intestinal stromal tumors with skeinoid fibers. Clinicopathological, immunohistochemical, and ultrastructural investigations.

Microscopic appearances of spindle cell tumors of the gastrointestinal tract are suggestive of smooth muscle origin; however, they usually lack specific muscle cell features by electron microscopy and immunohistochemistry, thus justifying their designation as stromal tumors. The present report describes nine cases of small intestinal stromal tumors with eosinophilic stromal globules composed of tangles of curved fibers with crossbands simulating an appearance of skeins, designated as skeinoid fibers. Patients' ages ranged from 28 to 87 years; and four were male. The tumors presented as well-delineated mural nodules ranging from 1.8 to 13 cm in size, causing intestinal obstruction or hemorrhage. Four were in the duodenum, three in the jejunum, and two unspecified. Microscopically, seven were benign; one, to the largest, was definitely malignant and metastasized to the liver. Another, the second largest (7.5 cm), showed moderate atypia with two mitoses per 10 high-power fields. The light microscopic appearance, including immunohistochemistry, were typical for small intestinal stromal tumors. Skeinoid fibers were strongly periodate-Schiff's procedure-positive and stained blue with the trichrome stain. They appeared as a few micra-sized specks to large globules reaching a few millimeters. Skeinoid fibers were also found in three neurogenic spindle cell tumors (an acoustic neuroma, a neurofibroma, and a plexosarcoma of the mesentery), suggesting that such fibers are possible ultrastructural markers for neurogenic tumors and thus small intestinal stromal tumors with skeinoid fibers are neurogenic in origin.

Actins↗
PubMed1992

Immunocytochemical identification of Rochalimaea henselae in bacillary (epithelioid) angiomatosis, parenchymal bacillary peliosis, and persistent fever with bacteremia.

We report the immunocytochemical identification of Rochalimaea henselae, a newly recognized fastidious, Gram-negative, Warthin-Starry-positive organism, as the common pathogen in bacillary angiomatosis (BA), bacillary peliosis (BP) of the liver and spleen, and persistent fever with bacteremia in immunocompromised patients. Immunogenic proteins of the R. henselae strain isolated from the blood of a febrile immunocompromised patient with BP of the liver were used to produce primary immune serum in rabbits. Using immunocytochemical procedures, the polyclonal antiserum reacted strongly not only with the immunizing strain of the bacteria, but also with other blood isolates of R. henselae (five cases) from both immunocompromised and immunocompetent patients and with the organisms present in the tissue lesions of cutaneous BA (five cases) and BP of the liver (two cases) and spleen (one case). The blood isolates and BA and BP tissue samples were obtained from widely separated geographic areas. The antiserum was weakly cross-reactive with cultures of Rochalimaea quintana, an organism closely related to R. henselae, but this reactivity was eliminated by specific adsorption. The antiserum did not cross-react with the Warthin-Starry-positive organisms associated with cat scratch disease (Afipia felis), syphilis (Treponema pallidum), Lyme disease (Borrelia burgdorferi) or chronic active gastritis (Helicobacter pylori). Likewise, the antiserum did not identify organisms in eight cases of Kaposi's sarcoma, a disorder of immunocompromised patients that is clinically similar to BA. Further studies are needed to determine the prevalence of this newly recognized organism as well as its possible involvement in other angioproliferative diseases.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Skeinoid fibers.

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Biomarkers, Tumor↗
PubMed1992

A canine model for hepatic venoocclusive disease.

Hepatic venoocclusive disease is a frequent lethal complication of bone marrow transplantation. It has also been associated with hepatic irradiation and administration of chemotherapeutic agents without BMT. The pathogenesis and therapy of VOD are unclear. The present studies were directed at developing a canine model for VOD. Three groups of dogs were studied. Group one consisted of 8 dogs in which monocrotaline (MC) was administered at 125 mg/kg orally on an intermittent schedule. In 7 of the 8 dogs 6 to 9 doses of drug were administered between 42 and 110 days. Group 2 consisted of 6 dogs receiving busulfan 2 mg/kg/day for 17-25 days, when platelet counts decreased to less than 5 x 10(4)/mm3 or clinical bleeding occurred. Group 3 consisted of 2 dogs receiving 24 Gy and 4 dogs receiving 36 Gy of whole-liver irradiation. Seven of 8 dogs in group 1 developed significant liver function abnormalities and evidence of portal hypertension. Histologic findings of VOD were present at autopsy. Group 2 dogs failed to develop clinical or laboratory liver abnormalities, but 3 of 6 animals had minimal histologic evidence of VOD. Three of 6 dogs in group 3 receiving 36 Gy developed hepatic dysfunction and had findings of fibrosis at autopsy. It was concluded that MC administration produced consistent clinical and histologic features of VOD in dogs. Changes occurring after busulfan or total-liver irradiation administration were less reproducible. Dogs are a suitable large-animal model for studies of VOD.

Animals↗
PubMed1992

Polypoid endobronchial lesions. A manifestation of bacillary angiomatosis.

Polypoid endobronchial lesions occurred in a patient with acquired immunodeficiency syndrome (AIDS) with recent fever, skin lesions, lymphadenopathy, lung infiltrates, and pleural effusions. His condition improved with antimicrobials and vincristine. After therapy ceased, skin lesions recurred and gastroesophageal mucosal lesions developed. Bacillary angiomatosis was identified during retrospective analysis of skin and endobronchial biopsy specimens.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Evaluation of finger blood flow with Tc-99m MDP (methylene diphosphonate).

BACKGROUND: A variety of methods were used to establish objective diagnostic criteria of Raynaud's phenomenon. We intended to introduce another method, using radionuclide (Tc-99m methylene diphosphonate) scintigraphy, which is more objective, simple and economical than the past methods. METHODS: The finger blood flow with radionuclide scintigraphy was evaluated in 10 patients of Raynaud's syndrome, 12 patients of connective disease without Raynaud's symptoms, and 20 normal persons. After immersing one hand in ice water (4 degrees C) for 30 seconds, the hand was exposed to 22 degrees C room air for 15 minutes, and then the patients received the intravenous (IV) bolus of 20 microCi of Tc-99m methylene diphosphonate (MDP). At the same time, scintigraphic image of both hands started with the region of interest, including the second, third, fourth and fifth fingers distal to the metacarpophalangeal (MCP) joints. Computer recording of the counts in the region of interest every 2 seconds for 310 seconds was started on IV bolus injection. RESULTS: The 310 seconds cumulative digital blood flow ratio of cold exposed hand to room air exposed hand was significantly lower in Raynaud's group (p < 0.001), and the ratio of initial slope of activity curve was also lower in the Raynaud's group (p < 0.001). Of the 8 patients showing Raynaud's syndrome, 4 patients of scleroderma and 1 patient of multiple myeloma showed no improvement of finger blood flow in the cold exposed hand after 2 weeks of pharmacological therapy, but 1 patient of mixed connective tissue disease, 1 patient of Behcet's syndrome and 1 patient of SLE showed much improved finger blood flow after combined administration of vasodilator, calcium channel blockers and antiplatelet drugs. CONCLUSIONS: The evaluation of finger blood flow with 99mTc-MDP could be considered to be one of the simple, economical and new methods that can be used in the follow-up, objective assessment of therapeutic effect, and giving an aid in the study of the pathophysiology of the Raynaud's phenomenon.

Adult↗
PubMed1992

Rochalimaea henselae causes bacillary angiomatosis and peliosis hepatis.

BACKGROUND: Recent studies have demonstrated that a newly described agent of persistent bacteremia, Rochalimaea henselae, and the agent of bacillary angiomatosis are both closely related to Rochalimaea quintana. Bacillary peliosis hepatis seemed likely to have the same etiologic agent as bacillary angiomatosis. We sought these pathologic changes in patients from whom R henselae was cultivated. METHODS: For two patients whose histopathologic findings we reviewed, additional light and electron microscopy were performed. Their bacterial isolates were compared by electrophoretic patterns of outer membrane proteins, restriction endonuclease digestion patterns of DNA, and reaction with murine antiserum. RESULTS: A previously reported human immunodeficiency virus-infected man with persistent bacteremia due to R henselae was found to have bacillary peliosis hepatis. Rochalimaea henselae was also isolated from the spleen of a woman receiving immunosuppressive therapy after allogeneic renal transplantation. She had developed fever, liver and spleen nodules, and periaortic lymphadenopathy. Bacillary peliosis of her liver and spleen, as well as bacillary angiomatosis of liver, spleen, and a lymph node, were found. The bacterial isolates had comparable electrophoretic patterns of outer membrane proteins and of restriction endonuclease-digested DNA, which differed from the respective patterns of R quintana. Murine antisera raised to the first isolate reacted strongly with the second by means of immunoblot and immunofluorescence techniques, while reacting only weakly with R quintana. CONCLUSION: Rochalimaea henselae, recently recognized to cause persistent fever and bacteremia in immunocompetent and immunocompromised persons, also causes bacillary angiomatosis and parenchymal bacillary peliosis.

Acquired Immunodeficiency Syndrome↗
PubMed1992

The effect of anabolic steroids on the biomechanical and histological properties of rat tendon.

Twenty-four male rats were divided into four groups, with anabolic steroids and exercise as variables. Biomechanical tests and histological evaluations were performed. The results of the biomechanical tests suggested that anabolic steroids produce a stiffer tendon, which fails with less elongation. The energy at the time when the tendon failed, the toe-limit elongation, and the elongation at the time of the first failure were all affected significantly. Changes in the force at failure were not statistically significant. No alterations of structure were noted when the specimens were viewed with light microscopy. Alterations of the sizes of the collagen fibrils were noted on electron microscopy.

Anabolic Agents↗
PubMed1991

Cellular F-actin levels as a marker for cellular transformation: correlation with bladder cancer risk.

Previous findings in cultured cells that differentiated cells had markedly higher F-actin levels than undifferentiated cells (Cancer Res., 50: 2215-2220, 1990) suggested that quantitative F-actin measurements in urinary cells might provide diagnostic or prognostic information by identifying those individuals with cells tending towards a lower degree of differentiation. The feasibility of such an approach was investigated using a risk stratification schema. Bladder wash samples were obtained from 163 symptomatic patients being evaluated for bladder cancer and 41 asymptomatic controls without hematuria or other symptoms consistent with bladder cancer. F-actin levels were evaluated by flow cytometry using a fluorescent phalloidin probe. The risk of bladder cancer was stratified according to biopsy, either DNA ploidy by flow cytometry or quantitative fluorescence image analysis cytology, previous bladder cancer history, and hematuria. A strong correlation between the presence of cells with abnormally low F-actin content in cells obtained by bladder wash from 38 patients and biopsy-proved bladder transitional cell carcinoma (P less than 0.001) was observed. A strong correlation was also observed between the presence of cells with low F-actin content and risk of bladder cancer assessed by either stratification schema (P less than 0.0001). The correlation was more consistent with the stratification by quantitative fluorescence image analysis cytology because of the 37% false-positive rate of ploidy analysis by flow cytometry among the control patients. Further evidence that low F-actin was correlated with cellular abnormality was obtained from simultaneously labeling cells for F-actin and with M344 antibody, a monoclonal antibody against a low-grade bladder tumor-related antigen. These studies showed that the F-actin content of the M344-positive cells was lower than that of the M344-negative cells. These results suggest that F-actin could be an early and sensitive marker for bladder cancer detection and risk prognostication.

Actins↗
PubMed1991

In situ DNA hybridization analysis of oral papillomas, leukoplakias, and carcinomas for human papillomavirus.

Twenty-one papillomas, 23 ordinary benign keratoses, 13 smokeless tobacco keratoses, 10 verrucous hyperplasias, 10 verrucous carcinomas, 17 squamous cell carcinomas, 3 epithelial dysplasias, and 6 lichen planus lesions were evaluated for human papillomavirus (HPV) types 6/11, 16/18, and 31/33/35, with biotinylated double-stranded DNA probes by in situ hybridization. Sixty-two percent (13/21) of oral squamous papillomas were positive for HPV DNA. HPV DNA types 6 and 11 demonstrated the strongest reactivity. Of the 13 cases, 10 also showed some reactivity with HPV-16/18 and -31/33/35. None of the cases of keratoses, epithelial dysplasia, squamous cell carcinoma, verrucous hyperplasia, verrucous carcinoma, or lichen planus were positive for HPV DNA. This study confirms the consistent and frequent finding of HPV DNA in oral squamous cell papillomas and the inconsistency of being able to identify HPV DNA in keratotic, premalignant, or cancerous lesions of the oral mucous membranes.

Carcinoma, Papillary↗
PubMed1991

Poorly differentiated adenocarcinoma with lymphoid stroma (lymphoepithelioma-like carcinomas) of the stomach. Report of three cases with Epstein-Barr virus genome demonstrated by the polymerase chain reaction.

Lymphoepithelioma of the nasopharynx is an undifferentiated carcinoma with prominent lymphoid infiltration. Histologically similar tumors have been documented in the skin, lung, thymus, salivary gland, tonsil, and uterine cervix. The authors report three cases of gastric carcinoma that were histologically and immunohistochemically similar to lymphoepithelioma. The patients were elderly white persons (61, 76, and 77 years of age); two of them had previous partial gastric resections for benign ulcer disease. The tumors were located on the lesser gastric curvature (two cases) and at a previous anastomotic site (one case) and measured 3, 4, and 7 cm in largest dimension. Grossly, each neoplasm was a raised plaque-like lesion with a central ulcer. Microscopically, all three tumors were similar, with poorly differentiated polygonal tumor cells scattered throughout a dense lymphocytic background. In a few areas, tumor cells formed ill-defined cords. In two cases, the neoplasms invaded the gastric muscle layer but had a well-delineated (pushing) margin. The tumor cells were immunohistochemically positive for AE3-defined keratin, confirming their epithelial nature. The lymphocytes were a mixture of UCHL-1-positive T cells and L-26-positive B cells. Portions of the Epstein-Barr virus genome were present in all cases, as detected by the polymerase chain reaction. The morphologic features of these cases are similar to those of lymphoepithelioma in other anatomic sites, and these tumors represent a unique subtype of gastric carcinoma.

Adenocarcinoma↗
PubMed1991

Large vessel occlusion with vasculitis in systemic lupus erythematosus.

Patients with SLE may have acute large vessel occlusion due to vasculitis and/or circulating antiphospholipid antibodies, as illustrated by the case we have reported. Unfortunately, delayed medical attention led to gangrene of the foot and amputation. Early recognition and appropriate treatment may significantly decrease morbidity and mortality. Medical treatment may include corticosteroids, thrombolysis, anticoagulation, or immunosuppression.

Adult↗
PubMed1991

Dietary fructose produces greater nephrocalcinosis in female than in male magnesium-deficient rats.

The synergistic interaction of fructose and magnesium (Mg) deficiency on kidney calcification was compared in male and female rats. Male and female weanling rats were divided into four dietary groups: fructose or starch, with or without Mg. Rats were fed their respective diets for 9 weeks, and 24 h urine was collected to measure urinary output, pH, Mg, calcium (Ca), and oxalic acid. Rats were fasted overnight. After decapitation, blood was collected immediately, and kidneys were removed to determine their Mg and Ca content. Dietary fructose significantly increased kidney Ca in female rats fed deficient or adequate Mg diet and in male rats fed Mg-deficient diet only; the greatest kidney calcification occurred in female rats fed Mg-deficient diet (P less than 0.0001). Even in starch groups female rats fed the Mg-deficient diet showed some kidney Ca accumulation. The synergistic interaction of fructose and magnesium deficiency on nephrocalcinosis was significantly greater in female than in male rats. Low urinary output, optimal pH 6.8 for calcium phosphate precipitation, hypercalcaemia, hypercalciuria, hypomagnesuria, and low ratio of urinary Mg to Ca may independently or multifactorially contribute to nephrocalcinosis. The possible mechanism of this interaction is discussed.

Analysis of Variance↗