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C T Lin

Publications and source records attributed to C T Lin.

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

[Classification and interpretation of the oral swallowing phase using B+M mode ultrasound].

A cushion device and B+M mode ultrasonography technique were used in 30 healthy volunteers to study tongue movement during swallowing. M-mode images show an amplitude-time diagram, in which the entire tongue movement during swallowing can be easily scrutinized. The different tongue movements during swallowing result in several turning points on the graph of the M-mode sonogram, which divide the oral swallowing phase into five subphases (I, IIa, IIb, IIIa, IIIb). Based on this new classification of swallowing, the tongue movements of the participants were interpreted and classified.

Adolescent↗
PubMed1994

Correlations among tyrosine phosphorylation of Shc, p72syk, PLC-gamma 1, and [Ca2+]i flux in Fc gamma RIIA signaling.

Tyrosine phosphorylation plays a critical role in Fc gamma RIIA signaling. In a mouse macrophage cell line transfected with human Fc gamma RIIA, cross-linking Fc gamma RIIA led to the transient generation of inositol 1, 4, 5-trisphosphate (IP3), [Ca2+]i flux, and rapid tyrosine phosphorylation of cellular substrates, including Shc, PLC-gamma 1, and a tyrosine kinase p72syk. In addition, tyrosine phosphorylated Fc gamma RIIA was co-precipitated with activated PLC-gamma 1. In contrast, no tyrosine phosphorylation of Shc or PLC-gamma 1 was detected in cells transfected with mutant receptors that failed to trigger [Ca2+]i flux. PMA inhibits both tyrosine phosphorylation of Shc and IP3 production leading to [Ca2+]i flux. However, PMA does not affect tyrosine phosphorylation of PLC-gamma 1 and p72syk. These results suggest that tyrosine phosphorylation of Shc and PLC-gamma 1 is important for the initiation of [Ca2+]i flux, and that activation of protein kinase C may modulate the activity of PLC-gamma 1 through serine/threonine phosphorylation.

Amino Acid Sequence↗
PubMed1994

Fc receptor-mediated signal transduction.

Receptors for the Fc domain of IgG (Fc gamma Rs) on leukocytes mediate a pleiotropic response following cross-linking by immune complexes. Signaling events following cross-linking of B and T cell antigen receptors, Fc epsilon RI, and Fc gamma Rs share common elements. In each, signaling is initiated by receptor cross-linking by antigen or immune complexes and results in the activation of src family kinases and ZAP-70-related tyrosine kinases, which associate with members of the receptor complex. Subsequent events include phosphorylation on tyrosine of multiple cellular substrates including phospholipase C gamma 1 and PI3-kinase. The [Ca2+]i flux is an event secondary to phospholipase C gamma 1 activation. Protein tyrosine kinase inhibitors block both early events such as [Ca2+]i flux and the later effects of cytokine release and cellular proliferation.

Amino Acid Sequence↗
PubMed1994

Studies on the concentrations of arsenic, selenium, copper, zinc and iron in the hair of blackfoot disease patients in different clinical stages.

Flame atomic absorption spectrophotometric methods were developed for, arsenic, selenium, copper, zinc and iron in hair samples. Data from blackfoot disease patients at five clinical stages were compared with those from healthy controls. The copper and zinc concentrations showed only slight differences in all clinical stages, which indicated the less relation to blackfoot disease. The decrease of selenium and iron in all stages was attributed to the antagonistic effect of arsenic; arsenic increased in the first and second stages, but decreased in the later stages. The decrease of selenium and iron during the progression of the disease is thought to be due to persistence of the antagonistic effect of arsenic in the initial stages, so that very low concentrations of selenium are found in the advanced stages, despite the later decrease of arsenic. There was also a progressive decrease of iron with advance of the disease, and the later stages also showed a decrease in haemoglobin. It was shown that arsenic is a major cause of blackfoot disease, and that it antagonises selenium and iron, which decreased in the advanced clinical stages of the disease.

Aged↗
PubMed1994

Association of Epstein-Barr virus, human papilloma virus, and cytomegalovirus with nine nasopharyngeal carcinoma cell lines.

BACKGROUND: Epstein-Barr virus (EBV) has been proposed to be closely associated with nasopharyngeal carcinoma (NPC). To evaluate the actual relationship, EBV was analyzed in nine established NPC cell lines and in four original NPC biopsy specimens. EXPERIMENTAL DESIGN: We used Southern blot analysis alone or after polymerase chain reaction to determine whether EBV was present in our NPC cell lines. We also used in situ nucleic acid hybridization and in situ polymerase chain reaction to identify EBV in 4 original biopsy specimens. For comparison, we investigated the cell lines for the presence of human papilloma virus type 16 (HPV-16) and human cytomegalovirus (HCMV). RESULTS: Southern blots alone for detection of 3 viruses in 9 cell lines were all negative. PCR plus Southern blotting revealed that 5 cell lines contained EBV in earlier passages, and all became negative in later passages. Some cell lines also contained HPV-16 and HCMV. At earlier passages, some cell lines contained EBV, HPV-16, and HCMV concurrently. Three out of four biopsy specimens contained EBV in certain tumor cells, lymphocytes, and glandular epithelia. CONCLUSIONS: These findings indicate that EBV, HPV-16, and HCMV may be present in certain NPC cell lines and in only a small fraction of each positive cell line, and that a cell line may contain these three viruses concurrently. EBV is present not only in a fraction of tumor cells, but also in some lymphocytes and glandular epithelia in biopsy specimens. It is present as an episomal form but not as an integrated form in the infected cells, suggesting that the carcinogenesis of non-EBV containing NPC tumor cells is not related to EBV infection.

Base Sequence↗
PubMed1994

Video-assisted thoracoscopic T2 sympathectomy for hyperhidrosis palmaris.

BACKGROUND: Hyperhidrosis palmaris is a functionally and socially disabling problem. Thoracic sympathectomy of the T2 ganglion has proved to be the time-honored treatment modality. STUDY DESIGN: The results of this study demonstrate the effectiveness of video-assisted thoracoscope for treatment of hyperhidrosis palmaris. The possibility to apply different anesthetic techniques and to measure surface temperature change of the hand were documented as well. RESULTS: Eighty consecutive cases (159 procedures) of essential hyperhidrosis palmaris were treated by video-assisted thoracoscopic T2 sympathectomy between January 1991 and December 1992. The surgical results were classified as excellent (much improved, very dry) in 88.1 percent, good (improved, minimal wet) in 9.4 percent, and fair (slightly improved, still wet) in 2.5 percent of the patients. The postoperative complications included one prolonged air leakage, one hemothorax, two wound infections, and 15 cases of facial anhidrosis. There were no recurrent cases (mean follow-up, 14.5 months). Fifty-six patients had concomitant hyperhidrosis pedum. Interestingly enough, through unknown mechanism, 64.3 percent of the patients with concomitant hyperhidrosis pedum were cured after this procedure. CONCLUSIONS: Video-assisted thoracoscopy provides magnified surgical fields, which make thoracoscopic sympathectomy for hyperhidrosis palmaris an effective, safe, easy to use, and time-saving procedure. This technique is also excellent for teaching purposes and allows the assistant to participate in the operation.

Adolescent↗
PubMed1994

Association of heterotrimeric GTP binding regulatory protein (Go) with mitosis.

BACKGROUND: The heterotrimeric GTP-binding regulatory proteins (or G proteins) play an important role in regulation of membrane signal transduction. Previously, we have identified the beta-subunit of G proteins (G beta) to be closely associated with mitotic spindles. In the present study, we have conducted experiments to examine whether the G alpha subunit is also associated with mitotic spindles. EXPERIMENTAL DESIGN: We prepared polyclonal antibodies against synthetic oligopeptides from different G alpha subunits and used them to localize G alpha in a nasopharyngeal carcinoma cell line by both immunohistochemistry and immunoelectron microscopy, and to see whether any specific G alpha subunit was present in the mitotic spindle region. Subsequently, we used a colocalization method to identify the overlapping distributions of specific G alpha subunits and beta-tubulin. To be sure that the findings represented a general phenomenon, several other cell types were also examined. To identify whether the G alpha subunit in the mitotic spindle was present in a heterotrimeric form, we performed ADP ribosylation experiments. RESULTS: (a) Only Go alpha subunit but not Gi alpha or Gs alpha was localized in the mitotic spindle. (b) Go alpha was colocalized with beta-tubulin in the mitotic spindle. (c) The precise site of localization of Go alpha on spindle microtubules was confirmed by immunoultrastructural study. (d) The association of Go alpha with the mitotic spindle could be found in both human and animal cell types. (e) The mitotic spindle preparation could be ADP ribosylated in the presence of pertussis toxin. CONCLUSIONS: The heterotrimeric Go protein is shown to be closely associated with the mitotic spindle. This finding suggests that Go protein may play some role in the regulation of mitotic spindles in addition to its regulation of signal transduction in neuronal cell membranes.

Adenosine Diphosphate Ribose↗
PubMed1994

Pulmonary sequestration.

BACKGROUND: Pulmonary sequestration is a relatively rare congenital abnormality. It is a cystic mass of nonfunctioning lung tissue which lacks an obvious communication with the tracheobronchial tree and which receives all or most of its arterial blood from anomalous systemic vessels. METHODS: Six patients with intralobar pulmonary sequestration were treated at this Hospital from 1982 to 1993. The two males and four females had ages ranging from 15 years to 56 years. Five of the six patients were symptomatic, with histories of chronic cough, intermittent fever, hemoptysis, and/or pleuric chest pain. The other patient was asymptomatic. Locations of the lesion included the left lower lobe in three, the right lower lobe in two and the right middle lobe in one. RESULTS: All patients received surgical intervention. Lobectomies were performed in five, and segmentectomy in one. There was no postoperative complication or mortality and all have remained asymptomatic during the follow-up period. CONCLUSIONS: A high index of suspicion is the most important element in the diagnosis of pulmonary sequestration. Angiography is mandatory to demonstrate the aberrant arterial supply and the venous drainage of pulmonary sequestration. Surgery should be performed early in order to reduce potentially life threatening obstruction and infection, and hasten the return of normal pulmonary function.

Adolescent↗
PubMed1994

Thymic carcinoma. Ten years' experience in twenty patients.

Thymic carcinoma is a rare neoplasm with extremely poor prognosis. To evaluate the outcome of treatment in thymic carcinoma, we reviewed a 10-year (1982 to 1992) experience with 20 consecutive patients in Taichung Veterans General Hospital. There were 9 men and 11 women: ages ranged from 34 to 70 years old (mean 51.4 years). None of these patients had concomitant myasthenia gravis. All of the patients received surgical intervention, and the diagnosis was made by pathologic study. Postoperative staging was made according to the modified Masaoka staging system. None of our patients were in stage I. One patient (5%) had stage II disease, 12 (60%) stage III, and 7 (35%) stage IV. The pathologic subtypes of thymic carcinoma included eight squamous cell carcinomas, seven undifferentiated carcinomas, one lymphoepithelioma-like carcinoma, one clear-cell carcinoma, 1 mucoepidermoid carcinoma, and two carcinoid tumors. Curative resection could be done in seven patients (35%). The overall cumulative survival was 45.9% at 3 years and 34.4% at 5 years. The median survival times for patients with complete and incomplete resection were 39.0 months and 14.3 months, respectively (p = 0.1752). The median survival times of patients with postoperative radiotherapy and without postoperative radiotherapy were 39.3 months and 15.0 months, respectively (p = 0.0738). The median survival times of patients with squamous cell carcinoma and undifferentiated carcinoma were 25.4 months and 11.3 months, respectively (p = 0.1464). Our data show that complete resection, postoperative radiotherapy, and squamous cell carcinoma do not indicate a significantly favorable result, even though they result in longer median survival times. Yet a positive trend of favorable outcome in patients who received postoperative radiotherapy is ambiguously shown.

Adult↗
PubMed1993

Detection of low level of human papilloma virus type 16 DNA sequences in cancer cell lines derived from two well-differentiated nasopharyngeal cancers.

Human papilloma virus type 16 (HPV16) related sequences were detected in two EBV-negative nasopharyngeal carcinoma (NPC) cell lines derived from two well-differentiated NPC by polymerase chain reaction. E2 and E6 related sequences of HPV16 were demonstrated using two pairs of primers derived from these two regions. DNA sequence analysis of amplified products excluded the possibility of laboratory viral DNA contamination.

Antigens, Viral↗
PubMed1993

Cloning and characterization of a cDNA encoding the cytosolic copper/zinc-superoxide dismutase from sweet potato tuberous root.

A full-length cDNA clone encoding a putative copper/zinc-superoxide dismutase (SOD) of sweet potato, Ipomoea batatas (L.) Lam. cv Tainong 57, was isolated from a cDNA library constructed in lambda gt10 from tuber root mRNA. Nucleotide sequence analysis of this cDNA clone revealed that it comprises a complete open reading frame coding for 152 amino acid residues. The deduced amino acid sequence showed higher homology (78-86%) with the sequence of the cytosolic SOD than that of the chloroplast SOD from other plant species. The residues required for coordinating copper and zinc are conserved as they are among all reported Cu/Zn-SOD sequences. In addition, it lacks recognizable plastic or mitochondrial targeting sequences. These data suggest that the isolated sweet potato clone encodes a cytosolic Cu/Zn-SOD.

Amino Acid Sequence↗
PubMed1993

Characterization of seven newly established nasopharyngeal carcinoma cell lines.

BACKGROUND: Nasopharyngeal carcinoma (NPC) has a relatively high incidence in Chinese living in Taiwan, Hong Kong, Singapore, and South China. To better understand this cancer, we have established several new NPC cell lines. EXPERIMENTAL DESIGN: We collected biopsy specimens from suspected NPC patients and divided each specimen into two parts: the first part was fixed for routine histopathologic examination, and the other part was put into culture medium for primary culture. Once the cell lines were established, they were extensively characterized. RESULTS: Seven NPC cell lines were established, and all have been passaged more than 100 times. Two lines were derived from keratinizing carcinomas and five from undifferentiated carcinomas. Electron microscopic examination revealed that both dark and light tumor cells contained intermediate filaments with clear desmosome formation. The average doubling time ranged from 10.7 to 16.3 hours. Karyotypic analysis showed multiple chromosome abnormalities with the average chromosome number between 84 and 95. Colony forming efficiency in soft agar was 18-42%. All cell lines could induce solid tumor mass formation when transplanted into nude mice, and the histopathological findings showed two keratinizing and five nonkeratinizing carcinomas. All cell lines contained less acidic keratin polypeptides than basic keratin polypeptides. Strong expression of vimentin in each single cell of all cell lines was also observed. The oncosuppressor retinoblastoma gene in each cell line showed no remarkable abnormality, but retinoblastoma protein was abnormally expressed in some interphase cells. The oncogenes, erbB and c-fgr, were both normally expressed. While the c-myc oncogene in all cell lines was overexpressed when compared with the Burkitt's lymphoma Raji Cell line, the c-myc DNA sequence in each cell line showed neither amplification nor rearrangement. CONCLUSIONS: The newly established seven NPC cell lines have been well characterized, and all showed overexpression of c-myc oncogene. The oncosuppressor retinoblastoma gene revealed no remarkable rearrangement, but its protein product was abnormal in certain interphase cells of each cell line.

Adult↗
PubMed1993

Sclerosing hemangioma of the lung: a clinicopathologic study.

The clinical and pathological features of 11 cases with sclerosing hemangiomas of the lung seen between 1982, and 1992 were reviewed. There were 1 male and 10 female patients aged 15 to 74 years (mean age, 53 years) at operation. Among the 11, 4 were asymptomatic, with the tumor discovered only on routine chest roentgenograms. All 11 patients had a solitary tumor showing as a well-defined homogeneous round or oval shadow on chest x-rays. Microscopically, 8 of the 11 tumors consisted of a mixture of the four major patterns: hemorrhagic, sclerotic, papillary and solid. Five patients received enucleation; four, wedge resection; one, segmentectomy and one, lobectomy. Since this tumor is usually clinically benign and surgically curative, thoracotomy and complete removal of the tumor by limited resection is recommended.

Adolescent↗
PubMed1993

[Carcinosarcoma of the esophagus].

Carcinosarcoma of the esophagus is a rare neoplasm of the esophagus, composes both of carcinomatous and sarcomatous elements. From Oct. 1982 to Sept. 1991, there were 516 neoplasms of the esophagus, 2 (0.39%) carcinosarcoma, treated at our hospital. The first patient was a 62-year-old man, pathological stage III (T3N2M0). The second patient was a 68-year-old man, pathological stage I (T1N0M0). The tumors were polypoid and located at the middle portion of the esophagus. They had received subtotal esophagectomy, mediastinal lymph node dissection and cervical esophagogastrostomy, retrosternally. The first patient has still lived disease free for seven years. The second patient died one year after the operation due to intra-abdominal lymphadenopathy, liver metastasis and massive ascites. As epidermoid carcinoma, radical esophagectomy with lymph node dissection is the standard procedure for carcinosarcoma of the esophagus.

Aged↗
PubMed1993

Surgical management of intrathoracic goiter.

Thirty-three consecutive patients of intrathoracic goiters underwent resection at the TCVGH during a nine-year period 1982-1991. The mean age of 21 men and 12 women was 65 years. Six (18 per cent) had undergone prior thyroid surgery. Thirty-one of the 33 patients were euthyroid. Thirty patients underwent transcervical approach for resection; three had cervical incision plus median sternotomy. Pathological examination revealed multinodular goiter in 31 (94 per cent) and follicular carcinoma in two (6 per cent). The mean mass of goiter was 201.25 g and the mean greatest dimension was 10 cm. Thyroidectomy is advisable in all cases of intrathoracic goiter and resection can almost invariably be performed through a transcervical approach.

Adult↗
PubMed1992

Expression of neurofibromin, the neurofibromatosis 1 gene product: studies in human neuroblastoma cells and rat brain.

Neurofibromatosis type 1 (NF1) is one of the most frequent Mendelian disorders in man and one of the most common autosomal dominant disorders affecting the nervous system. The NF1 gene has recently been cloned, and shows homology to the GTPase activating protein. In order to characterize the NF1 gene product, now called neurofibromin, we raised polyclonal antibodies against C- and N-terminal regions of neurofibromin and analyzed the protein by Western blot analysis and immunohistochemical studies of rat brain.

Amino Acid Sequence↗
PubMed1992

Fluorescence anisotropy studies of dibucaine.HCl in micelles and bacteriorhodopsin.

Emission and excitation spectra for the local anesthetic drug, dibucaine.HCl in neutral and charged surfactant solutions and in bacteriorhodopsin (bR) have been investigated for lambda(ex) = 266 nm at room temperature. The total fluorescence and fluorescence anisotropy decays of the anesthetic in the same environments were also measured using a picosecond laser/streak camera system (lambda (ex = 266 nm)). The total fluorescence decay gave two components for dibucaine micellar and dibucaine bR solutions, one component in the range of 200-500 ps and the other in the range of 1200-3400 ps. Only the nanosecond timescale component was found for the dibucaine monomer surfactant solutions (1200-3000 ps), indicating that the anesthetic resides in the bulk solution. The fluorescence anisotropy decays of dibucaine in Triton X-100 and in lithium dodecyl sulfate (LDS) micelles are approximately 200 ps, which is attributed to dibucaine solubilized in the micellar environment. Dibucaine.HCl in anionic monomer solution exhibits an unusually large fluorescence anisotropy, r(t)max = 0.22 and a depolarization decay of less than 100 ps. This presumably results from a head-to-tail exciplex aggregation between the positively charged dibucaine and negatively charged dodecyl sulfate surfactant molecules. The anisotropy decay of dibucaine in bR is 300 ps. This solution was the only one which exhibited a residual fluorescence anisotropy, r(infinity) - 0.08. This implies that dibucaine is restricted in its rotational motion and suggests protein binding rather than lipid solubility.

Anesthetics, Local↗