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C T Lee

Publications and source records attributed to C T Lee.

160 records · Page 9Linked to original sources

Diagnostic markers of prostate cancer: utility of prostate-specific antigen in diagnosis and staging.

The optimal tumor marker for prostate cancer would be effective for early detection, staging, and monitoring patients after definitive treatment. This marker would have a high sensitivity, specificity, and positive predictive value for distinguishing men with benign prostatic hyperplasia (BPH) from men with early prostate cancer. Such a marker would consistently detect biologically significant disease, correlate with clinical and pathologic staging, and predict prognosis. In addition, this marker would be accurate at indicating cure or progression of disease after treatment. Certainly, the ideal marker also would be reproducible, inexpensive, generate results rapidly, be easy to perform, be accessible to clinicians, and tolerable to patients. Unfortunately, such a "super" marker does not exist at this time. However, prostate-specific antigen (PSA) has many of the aforementioned capabilities. This article will describe the current utility of PSA in the diagnosis and staging of prostate cancer.

Acid Phosphatase↗

A clinical study of schizophrenic suicides. 42 cases in Taiwan.

A clinical study of 25 male and 17 female schizophrenic suicides is presented. Jumping from a height was the most common method used. The 42 suicidal schizophrenics in Taiwan were compared with both 84 sex- and age-matched and 60 5-year illness course non-suicidal schizophrenic control groups. The suicidal schizophrenics were not significantly different from the non-suicidal counterparts of both control groups with regard to age, sex, ethnicity, religion, educational background, the presence of suicide cases in the family history, and the presence of insight, but were significantly different in characteristics of a history of previous suicide attempts, presence of psychotic symptoms during their final month, depression during their final month, a history of depression, a history of previous psychiatric hospitalizations, and the number of hospitalizations. We discuss the findings from this study and others in the literature in the context of the different clinical and socio-cultural backgrounds of these Taiwanese schizophrenic suicides.

Adult↗

Alteration of cell growth and morphology by overexpression of transforming growth factor beta type II receptor in human lung adenocarcinoma cells.

TGF-beta is a potent inhibitory regulator of cell growth, which is transduced through interaction between type I (RI) and type II (RII) receptors that form heteromeric kinase complexes. Abnormal expression of these receptors has been identified in several human epithelial cancers and has been shown to be highly associated with resistance to TGF-beta. In this study, we investigated the expression of RI and RII in 13 human non-small cell lung cancer cell lines (NSCLCs) and demonstrated decreased or loss of RII expression in five lung cancer cell lines, but not of RI. Of these cell lines, the role of RII in NCI-H358 adenocarcinoma, which lacks RII and is insensitive to TGF-beta, was investigated by transducing this cell line with a recombinant retrovirus expressing full-length TGF-beta RII. Stably transfected cells showed significant increase in RII mRNA and protein expression. These cells responded to exogenous TGF-beta1 with suppressed proliferation in a dose-dependent manner and G1 arrest accompanied by morphological change distinct from control cells. We also investigated whether overexpression of dominant-negative RII (dnRII) in NCI-H441 adenocarcinoma, which is sensitive but expresses low levels of RII, could block signaling through the receptor complex. The overexpression of this kinase-domain-truncated RII by expressing the retroviral dnRII construct led to loss of the ability to respond to TGF-beta1 and an exhibition of uncontrolled growth. These results suggest a close association between the loss of the expression of wild-type TGF-beta RII and carcinogenesis in human lung cancer cells.

Adenocarcinoma↗

Adenovirus expressing p27(Kip1) induces growth arrest of lung cancer cell lines and suppresses the growth of established lung cancer xenografts.

p27(Kip1) (p27) is a member of the universal cyclin-dependent kinase inhibitor (CDKI) family and a putative tumor suppressor gene. In several tumors including lung cancer, decreased expression of p27 is associated with poor prognosis. These observations suggest a potential role for p27 as a new gene therapy target. In this study, we constructed adenovirus expressing human p27 (ad-p27) and investigated its antitumor effects on human lung cancer cell lines. Upon transduction of several human lung cancer cells with ad-p27, a high level of p27 expression, with a decrease in cdk2 and an increase in cyclin E were observed. These changes resulted in G1/S arrest. Transduction of human lung cancer cell lines with ad-p27 showed in vitro growth inhibition and a marked suppression of colony formation upon soft agar clonogenic assay. Direct intratumoral injection of ad-p27 induced the growth suppression of established lung tumors in nude mice. From these observations, gene therapy using ad-p27 seems to offer a potential basis for the development of new cancer gene therapy modality and a useful tool to investigate the mechanisms of cell cycle control.

Adenoviridae↗

Ceftriaxone for treatment of primary syphilis in men: a preliminary study.

Eighteen male patients with primary syphilis were randomly assigned to one of the following treatment schedules: ceftriaxone (3 g in a single intramuscular [im] injection), ceftriaxone (2 g im daily for two days), ceftriaxone (2 g im daily for five days), and benzathine penicillin (2.4 X 10(6) units in a single im injection). The single 3-g dose of ceftriaxone cured three men, one had a sustained response, and one failed to be cured. Of the patients given 2 g of ceftriaxone im daily for two days, three were cured and two had a sustained response. All three men treated with 2 g of ceftriaxone daily for five days had a sustained response. In the group given penicillin, three men were cured, one had a sustained response, and one was lost to follow-up.

Adolescent↗

Chronic bullous dermatosis of childhood in Singapore.

Five cases of chronic bullous dermatosis of childhood (CBDC), a rare bullous disease, are presented. Also known as linear IgA bullous dermatitis, it has significant immunofluorescence findings. Treatment with dapsone, 50 mg daily, is recommended.

Child↗

Kimura's disease in a chronic hemodialysis patient.

Eosinophilia is not an uncommon finding in chronic dialysis patients. It is usually benign in nature although definite pathogenesis is unknown. We have encountered a young uremic Chinese adult who developed Kimura's disease after being on maintenance hemodialysis for about 3 years. Asymptomatic eosinophilia had been noted for 1 year and 8 months prior to the development of progressively enlarged neck masses, which leads to the diagnosis of Kimura's disease. In contrast to most cases, eosinophilia was first noticed before the neck masses appeared. There is often a close correlation between Kimura's disease and glomerular disease, where renal involvement is considered as a systemic manifestation. However, we do not have strong evidence to support this relationship between terminal renal failure and Kimura's disease in this patient. To our knowledge, our patient is the first reported case of Kimura's disease occurring in chronic hemodialysis patients. Eosinophilia persisted for nearly 2 years before the neck mass developed and recurred after the excision. Besides, our patient also demonstrated a chronic and recurrent course typical of Kimura's disease.

Adult↗

Frequency-dependent effects of sine-wave cranial transcutaneous electrical nerve stimulation in human subjects.

In a double-blind protocol, ninety healthy volunteer subjects received 30 minutes of constant current sine-wave cranial transcutaneous electrical nerve stimulation (TENS) of 5 Hertz (Hz), 100 Hz, or 2000 Hz frequency (current maintained below .5 mA for safety), placebo TENS, or no treatment. The five groups were compared on pre- to posttreatment changes in blood pressure, heart rate, peripheral temperature, and anxiety. Analysis showed significant reductions in systolic and diastolic blood pressure and heart rate after 100 Hz cranial TENS as compared to the other groups. No other differences achieved significance.

Adolescent↗

Gastric inhibitory polypeptide appears less important in mediating acid secretion.

BACKGROUND/AIMS: Gastric inhibitory polypeptide is recognized as an acid inhibitor, while its relationship with Helicobacter pylori colonization is unknown. The present study measured serum gastric inhibitory polypeptide levels in patients after various types of gastric resection and the influence of demographic characteristics including Helicobacter pylori on serum gastric inhibitory polypeptide levels. METHODOLOGY: The study included twenty patients who underwent distal gastrectomy for duodenal ulcer, 33 patients who underwent radical subtotal gastrectomy for gastric carcinoma and 7 patients who underwent total gastrectomy. Another 58 healthy subjects served as controls. Their demographic characteristics were recorded, while serum gastric inhibitory polypeptide levels were measured using a homemade radioimmunoassay kit. RESULTS: The serum gastric inhibitory polypeptide levels in the three patient groups and the controls were 246.2+/-38.7 pg/ml, 201.7+/-30.9 pg/ml, 183.5+/-34.5 pg/ml and 202.6+/-14.0 pg/ml, respectively. The difference among the four groups was not significant. Neither age, gender, body mass index, smoking, Helicobacter pylori colonization nor type of gastrectomy had an influence on serum gastric inhibitory polypeptide levels in the controls and the three patient groups. However, elapsed time since operation in patients following total gastrectomy exhibited a significant positive correlation with their gastric inhibitory polypeptide levels (r=0.89, p<0.05). CONCLUSIONS: Serum gastric inhibitory polypeptide levels remain unchanged in patients undergoing various types of gastrectomy. Colonization of Helicobacter pylori does not influence its level. This peptide is probably less important in mediating gastric acid secretion.

Aged↗

Alteration of distal esophageal motor functions on different body positions.

BACKGROUND/AIMS: This study tried to resolve whether changed body position influences esophageal manometric parameters. MATERIAL AND METHODS: A pneumohydraulic infusion system was employed to measure esophageal parameters for 32 healthy volunteers. They underwent two consecutive manometries on both supine and sitting positions in a random order. These motility measurements included lower esophageal sphincter pressure, dry/wet swallow induced contractile amplitude and interval of distal esophageal body, and its peristaltic speed. RESULTS: Sitting position evoked a higher lower esophageal sphincter pressure than the supine measurement (Mean +/- SD: 14.6 +/- 4.0 mmHg vs. 11.9 +/- 4.2 mmHg, p < 0.01). At the distal esophagus, a swallow led to a stronger contractile amplitude and longer interval on supine measurement. CONCLUSIONS: Recorded peristaltic speeds in various esophageal segments resulted in a difference while this result was mainly due to the different recorded body positions (p < 0.01). Partial esophageal manometric parameters recorded on sitting position are different from the supine measurement. Hence altered body position may modulate some distal esophageal motor functions.

Adult↗

Increased immunogenicity of tumors bearing mutant p53 and P1A epitopes after transduction of B7-1 via recombinant adenovirus.

The majority of human solid tumors are likely to express protein epitopes which can act as targets for cytotoxic T cells, but these are frequently not effectively recognized. We tested whether the introduction of the costimulatory molecule B7-1 using a recombinant adenovirus (Ad-B7) can result in effective induction of epitope-specific immunity in two tumor models that express defined endogenous protein epitopes: D459, a fibroblast-derived cell line transfected with a human missense mutant p53 (C to Y at position 135), and P815, a mastocytoma expressing the endogenous tumor epitope P1A. Under the conditions studied, both of these tumors grow and kill their hosts without evidence of significant immune rejection. However, after transduction with the adenovirus containing B7-1, both of these tumors lose tumorigenicity and elicit specific cellular immunity to the mutant p53 epitope in D459 and P1A in P815. In addition, animals exposed to B7-transduced tumor cells were protected from subsequent challenge with nontransduced tumor. Adenovirus has distinct advantages for this approach, as it has high infectivity not requiring in vitro culture, low lytic potential, and transient expression of sufficient duration for immunologic effectiveness but without significant concern over permanent genetic modification. We conclude that transduction of tumor cells with Ad-B7 can increase the immunogenicity of endogenous protein epitopes and may represent a practical therapeutic approach to system human cancers.

Adenoviridae↗

The inhibitory effect of adenovirus-mediated p16INK4a gene transfer on the proliferation of lung cancer cell line.

Abnormalities in the p16INK4a tumor suppressor gene are found in many lung cancer cell lines and primary lung cancer tissue. To examine its tumor suppressor function and potential adequacy in cancer gene replacement therapy, wild-type p16INK4a gene was inserted in an adenovirus derived gene delivery system and introduced into lung cancer cell lines (NCI-H441 and NCI-H157) that did not express p16INK4a. Western blot assay and immunocytochemistry demonstrated production of wild-type p16 protein in these cell lines. The biological function of exogenous p16 protein was confirmed by the inhibition of pRB phosphorylation. The expression of exogenous p16 protein via recombinant adenovirus significantly inhibited cancer cell growth and colony formation in vitro of NSCLC that can not express endogenous p16. The flow cytometric analysis showed these results correlated with G1 cell cycle arrest. These observations suggest the value of adenovirally-mediated p16INK4a gene replacement therapy for lung cancer.

Adenoviridae↗