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B Y Lee

Publications and source records attributed to B Y Lee.

At least 55 records · Page 3Linked to original sources
PubMed1995

Immunohistochemical localization, identification and regulation of the interleukin-1 receptor antagonist in the human endometrium.

There is evidence suggesting the importance of the interleukin-1 receptor type I (IL-1Rtl) and interleukin-1 beta (IL-1 beta) as mediator in local intercellular interactions in endometrial tissue and embryonic implantation. To complete our understanding of the entire endometrial IL-1 system in humans, we have investigated the immunohistochemical distribution of IL-1 receptor antagonist (IL-1ra) in the human endometrium throughout the menstrual cycle. We have also identified the forms of IL-1ra present in human endometrial cells. Immunoreactive IL-1ra was found in both cryostat and paraffin-embedded sections of human endometrium using the alkaline phosphatase-peroxidase (A-P) method with two different IL-1ra antibodies. IL-1ra was present throughout the entire menstrual cycle, located primarily in the endometrial epithelium. However, IL-1ra staining was significantly higher during follicular phase in comparison with early and mid-late luteal phases. Reverse transcriptase polymerase chain reaction of cultured stromal and glandular cells showed that these cells express the intracellular form of IL-1ra mRNA (icIL-1ra). Our results demonstrate the regulated presence of the icIL-1ra in the human endometrium. This finding supports a possible autocrine-paracrine role for the IL-1 system in the human endometrium and embryonic implantation.

Adult↗
PubMed1995

Purification, characterization, and genetic analysis of Mycobacterium tuberculosis urease, a potentially critical determinant of host-pathogen interaction.

Mycobacterium tuberculosis urease (urea amidohydrolase [EC 3.5.1.5]) was purified and shown to contain three subunits: two small subunits, each approximately 11,000 Da, and a large subunit of 62,000 Da. The N-terminal sequences of the three subunits were homologous to those of the A, B, and C subunits, respectively, of other bacterial ureases. M. tuberculosis urease was specific for urea, with a Km of 0.3 mM, and did not hydrolyze thiourea, hydroxyurea, arginine, or asparagine. The enzyme was active over a broad pH range (optimal activity at pH 7.2) and was remarkably stable against heating to 60 degrees C and resistant to denaturation with urea. The enzyme was not inhibited by 1 mM EDTA but was inhibited by N-ethylmaleimide, hydroxyurea, acetohydroxamate, and phenylphosphorodiamidate. Urease activity was readily detectable in M. tuberculosis growing in nitrogen-rich broth, but expression increased 10-fold upon nitrogen deprivation, which is consistent with a role for the enzyme in nitrogen acquisition by the bacterium. The gene cluster encoding urease was shown to have organizational similarities to urease gene clusters of other bacteria. The nucleotide sequence of the M. tuberculosis urease gene cluster revealed open reading frames corresponding to the urease A, B, and C subunits, as well as to the urease accessory molecules F and G.

Amino Acid Sequence↗
PubMed1995

Identification of macrophage and stress-induced proteins of Mycobacterium tuberculosis.

Using phosphorimager technology to quantitate differences in protein expression, we have investigated the modulation of protein synthesis by Mycobacterium tuberculosis in response to intracellular residence in human macrophages and, for comparison, in response to various stress conditions during extracellular growth. Proteins of M. tuberculosis growing intracellularly in human THP-1 cells and extracellularly in broth were labeled with [35S]methionine; during intracellular growth, host cell protein synthesis was inhibited with cycloheximide. The metabolically labeled proteins were separated by two-dimensional gel electrophoresis and quantitatively analyzed. Intracellular residence in macrophages induced a profound change in the overall phenotype of M. tuberculosis. The expression of at least 16 M. tuberculosis proteins was induced (at least a twofold increase compared with growth in broth) and 28 proteins repressed (at least a twofold decrease). Many of the phenotypic changes in protein expression induced during intracellular growth occurred during extracellular growth in response to stress conditions including heat-shock, low pH, and H2O2. However, the pattern of induced and repressed proteins was unique to each stress condition. Of the 16 macrophage-induced proteins, 6 were absent during extracellular growth under both normal and stress conditions. Such proteins are potential virulence determinants and/or they may be important in the cell-mediated and protective immune response to M. tuberculosis infection.

Bacterial Proteins↗
PubMed1995

Pulmonary scar carcinoma: report of three cases and review of the literature.

Pulmonary scar carcinoma was described as a distinct clinicopathological entity over 50 years ago. There are many theories on the formation of this entity. We present three cases of pulmonary scar carcinoma with a high ratio of adenocarcinoma. One patient had a favorable postoperative course despite a 14-month delay in treatment. Necropsy specimen of another patient showed two primary scar carcinomas unrelated to each other. Literature review and discussion of etiology, diagnosis, and treatment modalities of pulmonary scar carcinoma were done. Pathogenesis and prognosis of the neoplasms associated with apical scars are not clearly understood.

Adenocarcinoma↗
PubMed1994

Axillofemoral bypass graft in a spinal cord injured patient with impending gangrene.

The axillofemoral bypass graft, an extra-anatomic graft, connects the axillary artery to the femoral artery and is used in the treatment of significant aortoiliac occlusive disease in poor-risk patients. A common indication for axillofemoral bypass is a "hostile abdomen" (postoperative adhesions, neoplasms or radiation). Less frequent indications are aortic mycotic aneurysm, infected aortobifemoral bypass graft, aortoduodenal fistula, inflammatory aneurysm and extensive retroperitoneal fibrosis. Spinal cord injured patients with peripheral arterial disease have two problems: 1) lack of premonitory symptoms (absence of claudication, paresthesias or rest pain) and 2) difficulty preventing pressure sores in the already poorly perfused limb. Indications for arterial reconstructive surgery are more drastic in this set of patients (impending gangrene and/or ischemic ulcers). Many spinal cord injured patients have sources of possible contamination (cystostomy and/or colostomy) which make intra-abdominal clean surgery impossible. We present a spinal cord injured patient with a permanent cystostomy and impending gangrene of the left foot. He underwent a left axillofemoral bypass graft and had a good postoperative course. We conclude that axillofemoral bypass graft is a good alternative for limb salvage in the spinal cord injured patient, especially when there is a source of possible contamination (colostomy and/or cystostomy) that would interfere with more common bypass grafting. The role of the noninvasive vascular laboratory for early detection of vascular disease is emphasized.

Aortic Diseases↗
PubMed1994

Impact of positive findings at image-guided biopsy of lymphoma on patient care: evaluation of clinical history, needle size, and pathologic findings on biopsy performance.

PURPOSE: To analyze the effect of findings at image-guided biopsy of abdominal lymphoma (IGBL) on patient care and define the key determinants of clinical success. MATERIALS AND METHODS: A retrospective, bi-institutional study was performed in 102 patients with positive or suspicious IGBL findings (93 patients with non-Hodgkin and nine patients with Hodgkin lymphoma). The proportion of patients treated on the basis of IGBL findings only was calculated and correlated with 10 determinants, including history of lymphoma, biopsy technique, needle size, immunocytochemical findings, and tumor grade. RESULTS: Overall, 73 patients (72%) were treated on the basis of biopsy findings only, including 41 (91%) of 45 patients with a history of lymphoma and 32 (56%) of 57 patients with no such history (P < .01). No difference in findings existed when three needle-size groups were compared (P > .50). CONCLUSION: Whenever findings were positive, IGBL provided enough tissue to enable treatment in most patients. Fine needles were just as likely as larger needles to enable both determination of tumor grade and treatment.

Biopsy, Needle↗
PubMed1994

Small (< or = 3 cm) renal masses: correlation of spiral CT features and pathologic findings.

OBJECTIVE: We describe our 3-year experience using spiral CT in the evaluation of small renal masses in order to determine the usefulness of this technique for classifying the lesions and to correlate specific CT features with pathologic findings. MATERIALS AND METHODS: We retrospectively analyzed spiral CT scans and results of pathologic examinations of surgically extirpated small (< or = 3 cm) renal masses in 35 patients. The masses included 27 renal cell carcinomas, two transitional cell carcinomas, one leiomyoma, one angiomyolipoma, and four benign cysts. Several imaging features, including attenuation, pattern of contrast enhancement, presence and type of calcification, cyst wall, and septation, were correlated with pathologic findings. RESULTS: Most renal cell carcinomas had a solid growth pattern (n = 19), had attenuation values on unenhanced scans of 20 H or greater (n = 26), and had attenuation values that increased by at least 10 H with contrast enhancement (n = 26). Only three renal cell carcinomas were mostly cystic on pathologic examination. Heterogeneous enhancement correlated with the presence of acellular regions (p = .02). Of 12 cystic masses, spiral CT showed the absence of a thick or nodular fibrous capsule in seven of nine masses (specificity, 0.78) and the absence of several (or nodular) septations in six of seven masses (specificity, 0.86) but was not as sensitive in detecting these features. CONCLUSION: Spiral CT can show many of the key imaging features of small renal masses used to distinguish between benign and malignant lesions. However, despite the theoretical benefits of volumetric CT, some lesions remain indeterminate and require surgical removal for diagnosis.

Carcinoma, Renal Cell↗
PubMed1993

Aortic blebs: an indication for urgent surgery.

A blister on an aortic aneurysm represents the final stage before rupture, regardless of patient symptoms or aneurysm size. The mechanisms of rupture are unclear but probably involve defects in the elastin and collagen matrices.

Aged↗
PubMed1993

Changes in spectral indices of heart rate variability during exercise in acute myocardial infarction.

Physical exertions are related to sudden cardiac death following acute myocardial infarction (AMI). Abnormalities in the autonomic modulation during exercise were noted in animals with AMI that were susceptible to potentially lethal arrhythmias. This study was done to evaluate the changes in the autonomic activity during exercise and recovery in AMI patients with good exercise capacity, using spectral analysis of R-R intervals of electrocardiogram (ECG). Symptom-limited treadmill exercise test was done on 17 patients of AMI with mild heart failure (in 7-10 days after the attack) and 21 healthy controls. The exercise was divided into 7 stages; rest, early exercise, mid-exercise, peak exercise, early recovery, mid-recovery, and late recovery. Power spectral analysis of R-R intervals of ECG was performed for each stage. Low frequency (0.04-0.15 Hz) and high frequency (0.15-0.40 Hz) powers, and their ratio were obtained. These parameters were observed throughout the stages in both groups. The trend of their changes during exercise and recovery was essentially the same for both groups; high and low frequency powers progressively decreased during exercise and abruptly increased during early recovery, but did not return to the values at those of rest until 9 minutes into the recovery. When the parameters were compared between the groups, there was a significantly greater decrease of high frequency power during the early exercise (p < 0.05), and a higher ratio of low to high frequency power during the early recovery (p < 0.05) in the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Electrocardiography↗
PubMed1993

Distal thigh/arm index as a predictor of success for lumbar sympathectomy.

Data from 90 lumbar sympathectomies were reviewed to assess the role of a distal thigh/arm Doppler systolic index (DTAI) and of external magnetic flowmeter (MCBF) measurements for predicting patient outcome following lumbar sympathectomy. The presenting symptoms included impending gangrene, gangrene, rest pain, nonhealing ulcers, and disabling claudication. Of the 90 cases, clinical improvement occurred in 57% of the limbs. Major amputation was not required in 73% of the limbs. The MCBF data showed variability which masked the relationship to the effects of sympathectomy. DTAI test results were significantly related to outcome. For DTAI > 0.6 (57 patients), improvement occurred in 70% of the limbs, with major amputation not required in 86% of the limbs. For DTAI < 0.6 (33 patients), improvement occurred in only 33% of the limbs, and major amputation was not required in 52% of the limbs. The Doppler systolic index has provided a noninvasive measure that can be used in conjunction with good clinical judgment for predicting the outcome of lumbar sympathectomy.

Amputation, Surgical↗
PubMed1992

Characterization of the major membrane protein of virulent Mycobacterium tuberculosis.

A protein with a molecular mass of 19 kDa was isolated and purified from enriched membrane fractions of the virulent Erdman strain of Mycobacterium tuberculosis. The protein is different from another 19-kDa protein, a lipoprotein, that was recently described (D. B. Young and T. R. Garbe, Res. Microbiol. 142:55-65, 1991). The sequencing strategy applied to this major membrane protein employed four different endoproteinases and resulted in sufficient overlapping peptide sequences for assignment of the entire protein sequence. Electron spray ionization mass spectrometry demonstrated a measured mass of 16,100, deviating from the predicted mass by only 2.86 atomic mass units. The sequence of this protein is unique. However, some similarities with other low-molecular-weight heat shock proteins were observed. Immunoblotting indicated that this protein is highly expressed in the virulent strains of M. tuberculosis. Its application to sera from patients with pulmonary tuberculosis showed promise as a serodiagnostic tool.

Amino Acid Sequence↗
PubMed1991

Prevalence of serum antibody to the type-specific glycopeptidolipid antigens of Mycobacterium avium in human immunodeficiency virus-positive and -negative individuals.

An enzyme-linked immunosorbent assay was constructed by using as antigens the type-specific immunodominant glycopeptidolipids of selected serotypes of Mycobacterium avium. This assay system was used to determine the prevalence of raised antibody levels to these antigens in groups of controls, human immunodeficiency (HIV)-negative and -positive homosexual men, and HIV-negative patients with active M. avium infections as a possible indicator of potential exposure and/or colonization by M. avium in these individuals. The results indicate that while antibody levels were raised in only 2.4% of control individuals, 33% of HIV-negative homosexual men and 44% of HIV-positive patients exhibited raised levels. Moreover, further examination of the HIV-positive group revealed no correlation between antiglycopeptidolipid antibody activity and helper T cell numbers. These data indicate that exposure to M. avium is prevalent among the homosexual male population, regardless of their HIV status. Moreover, the data are suggestive that the emergence of disseminated M. avium disease in HIV-positive patients may sometimes arise from earlier colonization, rather than as a newly acquired infection during terminal immunodeficiency.

Adult↗
PubMed1991

Cross-cultural study of alcoholism: comparison between Kangwha, Korea and Yanbian, China.

A cross-cultural comparison study of alcohol use disorder between Kangwha and Yanbian was conducted using the Korean version of the Diagnostic Interview Schedule (DIS). The subjects of the two areas studied were all native Koreans but lived in different sociocultural environments. A significant difference in lifetime prevalence rate of alcohol abuse (Kangwha 16.48%, Yanbian 6.95%; p less than 0.05) and similarity of alcohol dependence (Kangwha 10.23%, Yanbian 11.50%; p less than 0.05) were found. Among a total of 21 items of alcoholic symptoms, 14 items showed significant differences in frequencies between the two areas. The authors have suggested that alcohol abuse and alcohol dependence are two different diagnostic categories in origin, alcohol abuse is more related to socio-cultural environment and alcohol dependence to biogenetic background. The authors have discussed the possible reasons for a higher prevalence rate of alcohol abuse in Kangwha compared to Yanbian.

Adolescent↗
PubMed1990

A compartment model for fluorometric indication of tissue perfusion.

Sodium fluorescein is an in vivo blood perfusion indicator for soft tissue. When fluorescein dye is introduced into the blood, it distributes throughout the vasculature and the extravascular space. Incident light from an external source causes the dye to fluoresce, the level of which is monitored by a photodetector placed over the tissue. In this study, theoretical analysis incorporating a multicompartmental model for dye distribution is applied to describe the relationship among perfusion, dye kinetics, and fluorescence readings. Errors in calculating perfusion from fluorescence are related to dye concentrations and to measurement errors. These error sources are minimized by selecting the measurement time. The alternatives of measurement during wash-in or during wash-out of dye are compared, as well as the alternatives of introducing dye by bolus injection or by constant infusion. Compensation of wash-in measurements for differences in skin pigmentation is accomplished by the matching of skin optical properties between incident and fluorescing wavelengths. A laboratory study at 80 measurement sites (from ten graded perfusion canine flaps) demonstrated a correlation of wash-in and wash-out perfusion data ranging from 0.88 to 0.96 at typical levels of fluorescein in blood. Since wash-in can be completed in a matter of a few minutes, this is likely to be preferable in the clinical setting to wash-out which can take much longer to complete.

Animals↗