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S F Lin

Publications and source records attributed to S F Lin.

At least 109 records · Page 6Linked to original sources
PubMed1991

The spliced leader gene of Angiostrongylus cantonensis.

A 5' leader sequence has been identified on mRNAs of the parasitic nematode Angiostrongylus cantonensis. A 720-bp XhoI restriction fragment containing the gene encoding the leader sequence has been cloned and sequenced. It contains a 22-nt sequence identical to that of the leader sequence of Caenorhabditis elegans, a consensus splice site and a putative Sm antigen binding site. The gene is present as a tandem repeating unit of approximately 60 copies, and unlike C. elegans it is not associated with the 5S ribosomal RNA gene. The SL-RNA is 110 nt long and the sequence and primer extension studies suggest that it is transcribed from the tandemly repeating SL gene. It is precipitable from cell-free extracts of adult nematodes by anti-Sm anti-sera, and from RNA by anti-TMG anti-sera, thus suggesting its inclusion with small nuclear ribonucleoproteins in RNA splicing.

Amino Acid Sequence↗
PubMed1991

Effects of Q-switched Nd:YAG laser irradiation on neural impulse propagation: I. Spinal cord.

We studied the effect of irradiation with Q-switched Nd:YAG laser light (1064 nm) on spinal cord dorsal column and dorsolateral white matter in anesthetized rats. To evoke a synchronous sensory input, the sciatic nerve was stimulated electrically and the resulting evoked spinal cord potential (SCP) recorded from the dorsal columns of the ipsilateral side. The waveshape of the SCP showed three components: an early positive peak (P1), representing the responses of the most rapidly conducting fibers, followed by two negative peaks (N1 and N2), which are mainly due to synaptic effects of the volley on dorsal horn cells located in dorsal grey matter. Laser irradiation at 50 mJ/pulse and above resulted in severe reduction in the amplitudes of N1 and N2. In contrast, there was either no reduction at all or only a slight decrease in the amplitude of P1. The selective loss of the synaptic field might be mediated by impairment of synaptic transmission or by loss of high threshold fiber input to dorsal horn neurones. In either event it is likely that the mechanism of the differential effects of laser irradiation on the components of the electrically evoked SCP is at least in part photothermally mediated, since intracord temperatures during laser application greatly exceeded the physiological range.

Animals↗
PubMed1991

Effects of Q-switched Nd:YAG laser irradiation on neural impulse propagation: II. Dorsal roots and peripheral nerves.

We have studied the effects of Q-switched Nd:YAG laser irradiation on transmission of neural impulses in sensory nerve fibers in anesthetized rats and cats. Laser light was applied to dorsal roots (rat, cat) and to the sciatic nerve (rat) at increasing pulse energies ranging from 10 to 100 mJ/pulse for 5 minutes each. Compound action potentials recorded from dorsal roots and the sciatic nerve in response to high intensity electrical stimulation during laser application at increasing pulse energies showed a progressive preferential reduction of the slow late component of the electrically evoked response. Preliminary data from multifilament recordings from dorsal roots in cats demonstrated that conduction in small slow conducting fibers was blocked at lower laser pulse energies than in fibers with faster conduction velocities. These results imply, that laser light might have differential effects on slow versus fast conducting sensory nerve fibers. It is most likely that the preferential effect of laser irradiation on slow conducting fibers is mediated by photothermal mechanisms, since temperature increased substantially during laser application.

Action Potentials↗
PubMed1991

Mutation analysis of the ras gene in myelocytic leukemia by polymerase chain reaction and oligonucleotide probes.

Twenty-nine patients with acute myelocytic leukemia (AML) and 14 patients with Philadelphia chromosome-positive chronic myelocytic leukemia (CML) were analyzed to detect the presence of mutations in their ras genes by the polymerase chain reaction and oligonucleotide hybridization methods. Deoxyribonucleic acid (DNA) isolated from blood or bone marrow samples was screened for mutations in codons 12, 13 and 61 of N-ras and in codons 12 and 61 of K-ras and H-ras. We detected mutations of the ras gene in 7 patients with AML (7/29), all in N-ras. The mutations were 3 GGT- greater than GAT transitions in codon 12, 1 GGT- greater than TGT transition in codon 13, and 3 CAA- greater than AAA transitions in codon 61. No correlation has been observed between French-American-British subtypes and the incidence of N-ras mutation, nor between cytogenetic changes and the incidence of N-ras mutation. All ras gene mutations detected by the oligonucleotide hybridization method were further confirmed by direct sequencing. No mutations were detected in ras genes in samples from the 14 Philadelphia chromosome-positive CML patients (12 in chronic phase, 2 in blastic phase). These findings are in line with previous results indicating that ras gene mutations in the codons tested play only a small role in the tumorigenesis of CML.

Adolescent↗
PubMed1991

Remission of hypoplastic acute leukemia by low dose Ara-C: one case report.

The occurrence of hypoplastic acute leukemia is widely recognized as an atypical leukemia, and is defined as hypocellular marrow with more than 30% blasts and none or few blasts in the circulating blood. The pathogenesis of hypoplastic acute leukemia is still unknown. Clinically, it usually follows a less progressive course and has a high prevalence rate among the elderly. The treatment and prognosis remains unclear. We present a case of hypoplastic acute leukemia, which responded well to low dose Ara-C. The 67 year-old female patient had symptoms of bruising easily and dizziness for about 3 years. Initial investigation revealed pancytopenia in the circulating blood and hypocellularity (10%) with blast cells (60%) in the bone marrow. Besides supportive treatment with blood transfusions and antibiotics, chemotherapy of low dose Ara-C 10 mg/m2 was administrated for 14 days by subcutaneous injection. Bone marrow examination revealed an increase of cellularity and a decrease of blast cells following chemotherapy. Anemia and thrombocytopenia also simultaneously improved. Such results may suggest induction of differentiation effect of low dose Ara-C in hypoplastic leukemia.

Acute Disease↗
PubMed1991

Lactoferrin in rheumatoid arthritis and systemic lupus erythematous.

Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) are prototypes of autoimmune diseases. In order to assess the inflammatory status in these conditions, lactoferrin, stored in specific granules of neutrophils, was measured in serum samples of patients with SLE and RA. In RA, the mean serum lactoferrin level (1221.397 +/- 289.476 ng/ml) was significantly higher than that in normal individuals (753.364 +/- 124.063 ng/ml). Surprisingly, there were no significant differences between active SLE (672.682 +/- 356.154 mg/ml) and inactive SLE (642.267 +/- 270.456 ng/ml). Still, no differences were found between normal volunteers, active SLE and inactive SLE. Serum lactoferrin in SLE correlated significantly with CRP (Rs = 0.4089, p less than 0.01), but not with complement level and ANA titers. Thus in RA serum lactoferrin was highly elevated and this indicated that PMN in systemic circulation was activated. In SLE the correlation of CRP with lactoferrin reflected the role of later protein in inflammation.

Adolescent↗
PubMed1990

Erythrocyte complement receptor type 1 in non-SLE rheumatic diseases.

An investigation was conducted to measure the levels of erythrocyte complement receptor type 1 (CR1) in patients with various rheumatic diseases other than systemic lupus erythematosus, and to evaluate the clinical significance of this receptor in patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). Erythrocyte CR1 was measured in 37 normal controls and 106 patients with various rheumatic diseases. The levels of erythrocyte CR1 decreased significantly in patients with AS, juvenile rheumatoid arthritis, Sjögren's syndrome, and RA, while there was no statistical difference in levels of erythrocyte CR1 between normal controls and patients with gouty arthritis. This suggests that erythrocyte CR1 deficiency may occur in immune-mediated rheumatic diseases such as crystal-induced arthritis. In this study, we noted that the levels of erythrocyte CR1 were not related to the disease activity and severity of AS. The levels of erythrocyte CR1 were also not correlated with the clinical and laboratory parameters of disease activity in RA patients. However, there was a negative association between the levels of erythrocyte CR1 and titer of rheumatoid factor in RA patients. Further study is needed to determine whether or not the level of erythrocyte CR1 is related to prognosis in patients with RA.

Erythrocytes↗
PubMed1990

[Study on the effect of various conditions and age to blood platelet aggregation test].

The result of the platelet aggregation test was affected by various conditions. We performed the platelet aggregation test by changing different conditions, including: 1. adding different anticoagulants 2. interval between sampling and standing 3. platelet count 4. the concentrations of different reagents (ADP, Epinephrine and Collagen) respectively and the aggregation rate of blood platelet were compared among different age groups. The best condition for platelet aggregation rate was obtained as follows: 1) Citric acid of 3.8% is the best anticoagulant. 2) Test should be completed within 4 hours upon sample collection. 3) The optimal incubation temperature is between 25 degrees to 37 degrees C. 4) Platelet count of 2 to 4 x 10(5)/microliters gives the most constant result. 5) The optimal concentration for working solution of ADP, collagen and Epinephrine are 5.0 microns, 5.0 micrograms/ml and 50 microM respectively. 6) The aggregation rate of blood platelet increases with age.

Adenosine Diphosphate↗
PubMed1990

Chemotherapy for acute non-lymphocytic leukemia with low-dose cytosine arabinoside (Ara-C).

We administered low-dose cytosine arabinoside (Ara-C) to 32 newly diagnosed acute non-lymphocytic leukemia (ANLL) patients, 10 mg/m2 twice a day for 14-21 days, by subcutaneous injection or continuous intravenous infusion. CFU-GM of bone marrow cells were performed before low-dose Ara-C in some patients. Patients ranged in age from 21 to 78 years old. Ten showed complete remission and 16 partial response. The pretreatment CFU-GM pattern did not reflect the response to low-dose Ara-C. The major hematological effect of the treatment was myelosuppression, and most patients required platelet transfusion and the administration of antibiotics. Our study suggested that low-dose Ara-C treatment benefits some ANLL patients.

Adult↗
PubMed1990

Detection of beta-globin gene from single hairs.

DNA can be extracted from hair shafts and hair roots. The content of DNA in hairs is usually limited: the root end of hairs may contain 0.5 micrograms DNA and shed hairs contain less than 10 ng DNA. DNA analysis with restriction fragment length polymorphism (RFLP) requires microgram amounts of DNA. Such DNA cannot be obtained from such samples as single hairs or blood stains. Even with a little amount of DNA, specific genes of DNA can be greatly amplified to more than 10(6)-fold in vitro by polymerase chain reaction (PCR). We extracted the DNA from a half, 1, and 2 hair roots and 4 hair shafts and amplified the DNA with primer pairs (5'-GCACCATTCTAAAGAATAAC-3', 5'-GGATTGTAGCTGCTATTAGC-3') of the beta-globin gene, covering part sequences of the IVS-2 region by using the polymerase chain reaction for 50 cycles. The electrophoresis of the PCR product revealed a 131 base pairs band. Finally, we hybridized the PCR product with an IVS-2 probe (5'-GGGTTAAGGCAATAGCAAT-3'). A fragment of the IVS-2 extending from nucleotide 612 to 742 of the beta-globin gene can be demonstrated in the slot blot filter of hair roots and hair shafts, but not in the 1 microgram of blood which was not amplified by PCR. Detection of the beta-globin gene from single hairs by using the PCR may be useful for the diagnosis of thalassemia from single hairs.

Base Sequence↗
PubMed1990

Lymph node blast crisis of chronic myelogenous leukemia. One case report.

We present a patient with philadelphia chromosome (ph')-positive CML with extramedullary blast crisis in the lymph nodes before the bone marrow blast crisis. The morphological and cytochemical studies of lymph node touch preparation, and cytogenetic studies of lymph node tissue confirmed the extramedullary lymphoid blast transformation of CML, while the bone marrow continued to show the chronic phase of CML. When we changed our treatment to use Vincristine-Prednisolone therapy, the lymphadenopathy disappeared gradually. This case shows that the clinical and prognostic features of extramedullary disease can strongly affect disease acceleration in CML, and the therapy should be changed promptly. Besides, cytogenetic study of extramedullary tumor tissue in CML can be useful for accurate diagnosis.

Aged↗
PubMed1989

Preliminary crystallographic studies of the Fab fragment of an anti-azophenylarsonate antibody.

Single crystals of the Fab fragment of a murine A/J anti-azophenylarsonate monoclonal antibody have been prepared by the vapor diffusion method. Antibody 3A7 uses the same combination of variable region gene segments (VK, JK, VH, JH) as do anti-azophenylarsonate antibodies bearing a predominant cross-reactive idiotype, but utilizes a different D gene segment. The crystals grow in the presence of beta-octylglucoside as tetragonal bipyramids in the space group of either P4(1)2(1)2 or P4(3)3(1)2 and with unit cell dimensions of a = b = 77.9 A, and c = 146.7 A. They diffract X-rays to better than 2.7 A resolution. Data up to 2.7 A resolution have been collected.

Animals↗
PubMed1989

Erythrocyte complement receptor type I in patients with hematologic diseases.

Erythrocyte complement receptor type 1 (CR1) was measured in 37 normal controls and in 95 patients with various hematologic diseases. Levels of erythrocyte CR1 were significantly decreased in patients with acute myelocytic leukemia (AML), acute lymphocytic leukemia (ALL), chronic myelocytic leukemia, non-Hodgkin's lymphoma (NHL), aplastic anemia, idiopathic thrombocytopenic purpura, and multiple myeloma when compared to normal controls. There was also a trend of recovery of erythrocyte CR1 levels in AML and ALL patients when they were in a state of complete remission compared to those at time of onset or relapse. Further investigation is needed as to determine whether the level of erythrocyte CR1 can serve as a predictor for relapse of leukemia. This study also showed that the level of erythrocyte CR1 was not related to prognostic factors in NHL patients.

Erythrocytes↗
PubMed1989

Soluble interleukin-2 receptor levels in cerebrospinal fluid of patients with acute lymphocytic leukemia or with non-Hodgkin's lymphoma.

An elevated serum soluble interleukin-2 receptor (SIL-2R) has been noted in various hematological malignancies and conditions associated with active T-cell responses. Its appearance has also correlated with disease activity and tumor burden. Since few studies have been reported concerning SIL-2R in cerebrospinal fluid (CSF), work was undertaken to try to find if SIL-2R could be detected in the CSF of patients with acute lymphocytic leukemia (ALL) or non-Hodgkin's lymphoma (NHL), and whether it could become a clinical predictor of the central nervous system (CNS) involvement, and its response to therapy. Preliminary results showed that 1) the CSF SIL-2R is usually detectable in very low level with a mean of 15.1 +/- 14.2 units/ml compared with the mean serum level of 338.3 +/- 135.5 units/ml in eight normal controls; 2) there was no significant difference in the mean serum and CSF SIL-2R in five patients with ALL in a complete remission state compared with normal controls, while two ALL patients with CNS relapse and two NHL patients with CNS involvement had high levels of SIL-2R in CSF. High serum and low CSF SIL-2R levels were noted in another ALL case suffering from bone marrow relapse but without CNS relapse. It was also noted that decreased CSF SIL-2R concentration occurred subsequent to intrathecal chemotherapy in two ALL patients. From these results, we conclude that CSF SIL-2R might become a useful indicator of CNS involvement in patients with hematological malignancies and may predict response to chemotherapy.

Brain Neoplasms↗
PubMed1989

Circulating immune complexes in patients with hematologic diseases.

Circulating immune complexes (CIC) were measured by C1q-solid phase method in ninety-five patients with various hematologic diseases. The results showed significantly higher CIC levels in patients with acute myelocytic leukemia, chronic myelocytic leukemia, aplastic anemia and idiopathic thrombocytopenic purpura (ITP) than CIC levels in normal controls. However, there was no significant difference in such levels in patients with acute lymphocytic leukemia, non-Hodgkin's lymphoma and multiple myeloma when compared to normal controls. In this study, the level of CIC did not relate to prognosis for patients with non-Hodgkin's lymphoma. The findings demonstrated that a high level of CIC in patients with ITP usually responded poorly to steroid treatment. Other immunosuppressive agents were indicated in these cases. Therefore, the CIC level may serve as a therapeutic guide for the treatment of patients with ITP.

Antigen-Antibody Complex↗
PubMed1989

[The gap phenomena during ventriculoatrial conduction in man].

Eleven patients with retrograde gaps by conventional electro-physiological studies were reported. Most of the patients were studied because of arrhythmia. Electrical activity of the His bundle, atrium and routine ECG were recorded simultaneously. The excitability and characteristics in retrograde conduction were observed, using the programmed ventricular stimulus. The results of this study showed that two types of retrograde gaps occurred, Type I: The site of proximal delay was within the His Purkinje system (HPS), and the site of distal block was in the A-V node. Three of the 11 cases were of this type. Type II: Both the site of proximal delay and distal block are within the HPS in eight of the 11 cases. Comparing the data with those from our lab about the gap phenomena during atrioventricular conduction in 10 cases, it was found that in the gap phenomena of A-V conduction, the site of proximal delay is usually within the A-V node, whereas the site of distal block was in the HPS. In the gap phenomena of V-A conduction the site of distal block might be either above or below the His bundle, but the site of proximal delay was only occurred in the HPS. So retrograde gaps were more common than antegrade gaps depending upon the ratio of the functional refractory periods of two horizontal region in the A-V (or V-A) conduction system.

Adolescent↗
PubMed1989

Spontaneous pneumothorax following chemotherapy for malignant thymoma with pulmonary metastasis: report of a case.

Spontaneous pneumothorax is a rare complication in both primary and metastatic pulmonary neoplasms. Occasionally, pneumothorax is associated with chemotherapy of pulmonary malignancies. Pneumothorax after chemotherapy has been reported only in cases with osteogenic sarcoma, synovial sarcoma, fibrosarcoma, germinal tumors, and lymphoma with lung metastasis. We report a case of a patient with malignant thymoma who suffered from lung metastasis after radiation and adjuvant chemotherapy from lung metastasis after radiation and adjuvant chemotherapy (cyclophosphamide, adriamycin, and cis-platinum). A chest X-ray taken 2 days after chemotherapy showed bilateral pneumothorax, which was resolved with conservative treatment. The pneumothorax in this patient is believed to have been caused by the rupturing of the tumor into the pleural cavity and the bronchi.

Adult↗