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Biomedical subjects

F Lee

Publications and source records attributed to F Lee.

At least 199 records · Page 11Linked to original sources
PubMed1989

Transrectal ultrasound. A case report related to the natural history of prostate cancer.

This is a case report of a man with prostate cancer diagnosed 10 years ago by digital rectal examination and prostatic biopsy. He was followed with serial transrectal ultrasound examinations for the last 22 months. Transrectal ultrasound enabled us to observe the natural history of his cancer. Because of accelerated tumor growth, a radical prostatectomy was performed. The tumor was confined within the prostate capsule and thus considered a "cure." Transrectal ultrasound is an invaluable tool for continuous monitoring of patients with prostate cancer.

Adenocarcinoma↗
PubMed1989

IL-6 is a differentiation factor for M1 and WEHI-3B myeloid leukemic cells.

IL-6 has multiple biologic activities in different cell systems including both the ability to support cell proliferation and to induce differentiation. We reported previously the isolation and functional expression of a mouse IL-6 (mIL-6) cDNA clone derived from bone marrow stromal cells. In this paper, we show that mIL-6 is a potent inducer of terminal macrophage differentiation for a mouse myeloid leukemic cell line, M1. Addition of mIL-6 to cultures of M1 cells rapidly inhibits their proliferation and induces phagocytic activity and morphologic changes characteristic of mature macrophages. These phenotypic changes are accompanied at the molecular level by a decrease in proto-oncogene c-myc mRNA accumulation and increases in Fc gamma R, proto-oncogenes c-fos and c-fms (CSF-1R) mRNA expression. Furthermore, IL-6 enhances the expression of Fc gamma R and c-fms in differentiation-responsive D+, but not unresponsive D- sublines of mouse myelomonocytic leukemic WEHI-3B cells. Together with our previous observation that IL-6 stimulates colony formation by normal myeloid progenitors, these results strongly suggest an important regulatory role for IL-6 in myeloid cell growth and differentiation.

Animals↗
PubMed1989

IL-3 and stromal cell-derived factor synergistically stimulate the growth of pre-B cell lines cloned from long-term lymphoid bone marrow cultures.

The addition of IL-3 to modified Whitlock-Witte long-term lymphocyte cultures was found to enhance the growth of a small but significant number of B cell precursors supported by an adherent stromal cell monolayer. Several pre-B cell lines were cloned from IL-3-treated long-term lymphocyte cultures. The growth requirements and physical properties of one representative clone, BL/3, are described. BL/3 cells were shown to be unresponsive to IL-3 except when it is used at very high concentrations. In contrast, significant growth was stimulated by stromal cell conditioned medium previously shown to contain a pre-B cell growth factor. Optimal growth of the pre-B cell clone was stimulated by stromal cell conditioned medium plus IL-3. Synergy between the stromal cell-derived factor and IL-3 occurred when IL-3 was used over a wide range of concentrations including a relatively low amount that was ineffective as a growth stimulus by itself. The finding that more than one factor is required to sustain optimal growth of some pre-B cells parallels the complex growth requirements reported for some primitive myeloid/erythroid progenitors.

Animals↗
PubMed1989

Enhanced production of interleukin-6 in mice with type II collagen-induced arthritis.

We established an interleukin-6 (IL-6)-dependent cell line from murine plasmacytoma MOPC-104E cells. This cell line (designated PIL-6) was found to respond to murine and to human IL-6, but not to any other cytokines. We used this cell line to investigate the involvement of IL-6 production in type II collagen-induced arthritis in DBA/1 mice. Only marginal IL-6 activity was detected in sera from DBA/1 mice inoculated with Freund's complete adjuvant (FCA) alone, with an unrelated protein (bovine serum albumin) plus FCA, or with type II collagen plus Freund's incomplete adjuvant. However, enhanced IL-6 activity was observed in DBA/1 mice that had been injected with type II collagen plus FCA to induce arthritis. The elevated level of serum IL-6 activity was associated with high levels of IL-6 produced when lymph node cells from arthritic mice were stimulated in vitro with type II collagen. We also found that the L3T4+ T cell subset is responsible for the enhanced production of IL-6 in arthritic mice. The results are discussed in the context of potential roles of IL-6 in the induction and/or expression of chronic, progressive arthritis.

Animals↗
PubMed1989

Tissue distribution of murine hemopoietic growth factor mRNA production.

We have studied the tissue distribution of interleukin (IL) and hemopoietic colony-stimulating factor (CSF) transcripts in mice by S1-nuclease protection analysis. Accumulation of several of these mRNAs in response to intravenous injection of lipopolysaccharide (LPS) appears to occur in a tissue-specific fashion. IL-1 alpha transcripts accumulate in spleen and lung; IL-6 transcripts accumulate in kidney, heart, and spleen; granulocyte-macrophage-CSF transcripts accumulate in lung and heart; and granulocyte-CSF transcripts accumulate in heart. Three distinct patterns of in vivo mRNA accumulation were detected: 1) silent--interleukins 2-5 showed no transcripts in either LPS-treated or untreated animals; 2) induced--IL-1 alpha, IL-6, granulocyte-macrophage (GM)-CSF, and G-CSF transcripts were increased in abundance in LPS-injected mice; and 3) constitutive--M-CSF transcripts were found in similar amounts in both untreated and treated mice and were present in all tissues examined.

Animals↗
PubMed1989

Similarities between the stimulus properties of phenylpropanolamine and amphetamine.

Rats at 80% body weight were trained to discriminate 1.0 mg/kg d-amphetamine versus saline in a two-lever, discrete trial drug discrimination task to obtain food pellets. After reliable discriminative control of lever choice was established, various doses of d,l-phenylpropanolamine (PPA, i.e., d,l-norephedrine) were substituted for the amphetamine training dose in non-reinforced test trials. Test doses of 10, 20, and 40 mg/kg PPA resulted in over 90% responses on the amphetamine-appropriate lever. Lower doses (1.25, 2.5, and 5.0 mg/kg) resulted in predominantly saline-appropriate responses. The generalization seen after the 20 mg/kg dose of phenylpropanolamine was blocked by pretreatment with 0.5 mg/kg haloperidol, suggesting that the generalization from amphetamine to PPA was mediated by a dopaminergic mechanism.

Amphetamine↗
PubMed1989

Altered cytokeratin expression and differentiation induction during neoplastic transformation of cultured rat liver cells by nickel subsulfide.

Rat liver T51B cells were maintained in the presence of low concentrations of Ni(II) derived from alpha Ni3S2 for 3-15 months in culture in order to monitor cytokeratin, differentiation, and transformation patterns. Nickel exposures caused irreversible, heritable juxtanuclear aggregates of cytokeratin CK55, which increased in size and complexity with prolonged nickel exposure, eventually resembling Mallory bodies and expressing glutamyltransferase. Altered cytokeratin expression was accompanied by induction of differentiation, with markers of both bile ductular cells and hepatocytes, such as induction of cytokeratin polypeptides CK39 and CK49, cell morphology, and cytokeratin filament network changes; whereas control cultures similarly maintained for long periods in culture remained unchanged. Altered cytokeratin expression was also accompanied by acquisition of transformation markers--loss of density dependence, progression toward calcium independence, and (benign) growth in nude mice. Observed cytokeratin aberrations may be a factor in nickel carcinogenesis, in view of the known affinity of the metal for cellular structural proteins, especially keratin, which play a role in maintenance of cell behavior.

Animals↗
PubMed1989

Transrectal ultrasound: diagnosis and staging of prostatic carcinoma.

Transrectal ultrasound has developed into a sophisticated technology since its first clinical application, and ultrasound imaging is now widely accepted. When 7 MHz scanning was introduced in 1986, improved resolution depicted an infrastructure of the prostate that corresponded to McNeal's 1968 concept of zonal prostate anatomy. McNeal's definition of three glandular zones (i.e., transition, central, and peripheral) and one nonglandular region (i.e., anterior fibromuscular stroma) has allowed us to identify areas of anatomic weakness through which cancer may escape the prostate. These glandular zones have sites of anatomic weakness through which cancer may easily extend to the extraprostatic space, thus affecting eventual staging. Highly accurate, easy to perform, and readily accepted by patients, strategic ultrasound-guided transrectal biopsy can accurately sample all areas within the prostate, including areas of anatomic weakness.

Humans↗
PubMed1989

Prostatic intraepithelial neoplasia: a lesion that may be confused with cancer on prostatic ultrasound.

Most prostatic adenocarcinomas reveal a hypoechoic peripheral zone lesion on transrectal ultrasonography. Numerous benign processes can have similar transrectal ultrasound findings. We report 8 cases of transrectal ultrasound-guided prostatic biopsies of peripheral zone hypoechoic lesions that demonstrated prostatic intraepithelial neoplasia, a presumed premalignant lesion. Immunohistochemistry using an antibody directed against cytokeratins 5 and 14 was performed to exclude carcinoma. Of the men 2 had invasive carcinoma on repeat biopsy and 1 had carcinoma diagnosed on subsequent transurethral resection. Patients with prostatic intraepithelial neoplasia on biopsy of hypoechoic peripheral zone lesions merit careful monitoring.

Adenocarcinoma↗
PubMed1989

Use of transrectal ultrasound in diagnosis, guided biopsy, staging, and screening of prostate cancer.

TRUS allows visualization of the internal anatomy of the prostate gland. Knowledge of zonal prostate anatomy allows more accurate staging of prostate cancer by use of strategic TRUS-guided biopsy of sites of possible tumor extension. These biopsies may be facilitated via the transrectal route using an automatic Biopsy system. TRUS is twice as sensitive as DRE and is capable of detecting nonpalpable prostate cancer. TRUS can detect nonpalpable tumors with average dimensions as small as 1.0 cm. This size is considered to be clinically significant.

Biopsy↗
PubMed1989

IL-7 is a growth and maintenance factor for mature and immature thymocyte subsets.

The specific signals inducing the growth and maturation of thymocytes remain undefined. We show here that recombinant IL-7 induces growth of fetal and adult mouse CD4-8- thymocytes. IL-7 also induces a lower but significant response in CD4+8- and CD4-8+ thymocytes. Day 14 fetal thymic lobes cultured in IL-7 for 6 days show a 2-fold increase in cell number when compared to control cultures. The thymocyte subsets that proliferate in response to IL-7 can be maintained in culture for extended periods of time. CD4-8- thymocytes maintained in IL-7 did not change their phenotype with respect to CD4 and CD8 expression. In addition, we show that the combination of IL-7 plus IL-6 provides a potent growth stimulus for CD4+8- and CD4-8+ thymocytes. A cloned thymic epithelial cell, that can be induced to express MHC class II molecules, transcribes both IL-7 and IL-6 mRNA. A cloned thymic macrophage cell line produces IL-6 but no detectable IL-7 mRNA. The pattern of biological activities present in the supernatants of these cell lines is also presented. These observations suggest that the thymic epithelial and macrophage cell types may be an in vivo source of signals which mediate thymocyte development.

Animals↗
PubMed1989

Hypoechoic lesions of the prostate: clinical relevance of tumor size, digital rectal examination, and prostate-specific antigen.

Two hundred fifty-six patients with hypoechoic lesions of the prostate found at transrectal ultrasound (US) were evaluated with prostate-specific antigen (PSA) study, digital rectal examination (DRE), and US-guided transrectal biopsy. Positive predictive values for cancer were calculated for transrectal US alone and in combination with DRE, PSA study, or both. Results were correlated with lesion size. The positive predictive value for transrectal US alone was 41%; this value increased to 61% if the patient had positive results from DRE, 52% if the PSA level was elevated, and 71% if both the DRE results and PSA level were abnormal. The positive predictive value for transrectal US fell to 24% if results of the DRE were normal, 12% if the PSA level was normal, and 5% if both DRE results and PSA level were normal. No cancers were detected in lesions 1.0 cm or smaller if DRE results and PSA level were normal. DRE and PSA study are valuable complements to abnormal transrectal US examinations. Biopsy of small suspicious lesions may not be indicated if results of both of the studies are normal.

Adult↗
PubMed1989

Transrectal biopsy of the prostate guided with transrectal US: longitudinal and multiplanar scanning.

One hundred forty-nine ultrasound (US)-guided transrectal biopsies of the prostate were performed with an 18-gauge needle mounted in a spring-loaded firing device. Two probes were used, one with its sector transducer placed at the tip of the probe and the other with its sector transducer placed at an angle of 45 degrees. All biopsies provided a diagnostic tissue core. Histologic examination of biopsy specimens showed that 78 lesions were cancerous, 17 were dysplastic, and 54 were benign. Two patients developed fever; one of these received oral antibiotics after onset of the fever. Hospitalization was not required for either patient. The authors conclude that US-guided transrectal biopsy is a safe and valuable diagnostic tool.

Biopsy, Needle↗
PubMed1989

Transrectal ultrasound in the diagnosis and staging of prostatic carcinoma.

Indications for TRUS are: (a) for diagnosis of nonpalpable cancer, or detection of cancer with greater accuracy than is possible at present; (b) for guidance of transrectal biopsies of hypoechoic lesions for histologic confirmation of cancer; (c) for guidance of staging biopsies to ensure diagnoses of extraprostatic extension; and (d) for staging previously diagnosed prostate cancer.

Biopsy↗
PubMed1989

Diagnosis of prostate cancer by transrectal ultrasound.

The comprehensive description of the zonal anatomy of the prostate as developed by McNeal has identified the likely sites of cancer within the gland and provided further understanding of the way in which prostate tumors spread. Two areas where the capsule is deficient have been described: the invaginated extraprostatic space and the apex of the prostate, both of which are easy avenues along which tumor may escape the confines of the prostate. Cancer of the prostate is hypoechoic in comparison with the normal peripheral zone tissue in all cases and can be diagnosed with great accuracy by the use of ultrasound-guided biopsies. The sensitivity of transrectal ultrasound in the diagnosis of prostate cancer is twice that of digital rectal examination. In our clinical study, the overall positive predictive value of a hypoechoic lesion was 41 per cent, and it increased to 61 per cent when combined with the finding of a positive digital rectal examination and to 52 per cent if the prostate-specific antigen level was elevated. Thirty-two per cent of the cancers diagnosed with transrectal ultrasound were not detectable by digital rectal examinations.

Antigens, Neoplasm↗
PubMed1989

Use of transrectal ultrasound and prostate-specific antigen in diagnosis of prostatic intraepithelial neoplasia.

1. PIN can present as a hypoechoic lesion on ultrasound. 2. Biopsy results prove a close relationship between PIN and cancer. 3. Measurements of age, lesion size, and PSA for diagnoses of PIN were intermediate values between non-cancer and cancer. 4. Sequential, precise transrectal ultrasound-guided biopsies of hypoechoic lesions are now possible, and close follow-up of patients with diagnoses of PIN is therefore possible.

Adult↗