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L C Lin

Publications and source records attributed to L C Lin.

87 records · Page 5Linked to original sources
PubMed1989

[Dose-response of intrathecal morphine for post-cesarean analgesia].

Intrathecal morphine for post-operative analgesia is famous for its quality and safety, but its role in post-Cesarean analgesia is not well established. In this study, we investigate its analgesic effect, complication rate and neonatal outcome under various dosages of morphine. The parturients divided into five groups according to morphine dosage: 0, 0.1, 0.25, 0.5, 1.0 mg respectively. The duration of analgesic effect was 19.1 h in 0.1 mg group, 23.6 h in 0.25 mg group, 28.1 h in 0.5 mg group, 30.5 h in 1.0 mg group. Complication rate increased markedly as more than 0.5 mg morphine was injected. Respiratory inhibition (respiratory rate less than 10/min) that required naloxone treatment had occurred twice in 0.5 and 1.0 mg group respectively. Neonatal outcome did not bear any difference among the five groups. In conclusion, adding 0.1 to 0.25 mg morphine to intrathecal anesthetics can be effectively and safely extended into post-Cesarean analgesia.

Adult↗
PubMed1982

Complete amino acid sequence of the delta heavy chain of human immunoglobulin D.

We have determined the amino acid sequence of the variable (V) region of the delta heavy (H) chain of human IgD isolated from the plasma of myeloma patient WAH. This V region is unusual in its amino end group (arginine) and in its length (129 residues). The length is due to 10 insertions in the third complementarity-determining region (CDR3). A computer search showed that no reported CDR3-joining region (-JH) sequences are identical and that they appear to be unrelated to the constant (C) region sequences of immunoglobulins. The V region sequence together with our previous results for the C region give the complete sequence of the human delta chain WAH, which has 512 amino acid residues and a Mr congruent to 65,000. The human delta chain has four domains (V, C delta 1, C delta 2, and C delta 3) and a long hinge region; by comparison, the mouse delta chain lacks a continuous segment of 135 residues, including half the hinge region and the entire C delta 2 domain. The human and mouse delta chains also differ in the number, kind, and location of GlcN and GalN glycans and probably in conformation and quaternary structure. These and other considerations suggest that there may be multiple forms of both secreted and membrane-bound IgD that differ in size, structure, and function.

Amino Acid Sequence↗
PubMed1981

Primary structure of the Fc region of human immunoglobulin D: implications for evolutionary origin and biological function.

We have determined the complete amino acid sequence of a tryptic Fc delta fragment generated from an intact human IgD (WAH); it is 226 residues long and includes the second (C delta 2) and the third (C delta 3) constant domains of the delta chain. Comparison of the homology of the Fc sequence of the five human immunoglobulin classes suggests that either the delta-chain gene evolved from the alpha-chain gene soon after the divergence of a mu-alpha common ancestor or it evolved from an ancestral gene distinct from both the mu-alpha and the gamma-epsilon common ancestors. Comparative study using a spatial model of the Fc region indicates that the structure of the C delta 3 domain differs extensively from that of the carboxy-terminal domains of other heavy chain classes; this, together with the unique hinge region structure, probably reflects the biological role of IgD as a receptor molecule on the B-lymphocyte surface.

Amino Acid Sequence↗
PubMed1981

Amino acid sequence of the first constant region domain and the hinge region of the delta heavy chain of human IgD.

We have determined the amino acid sequence of the first constant (C) region domain (C delta 1) and the hinge region of the delta heavy chain of human IgD WAH and also the sequence of the adjacent COOH-terminal portion of the variable (V) region, including the JH region. Together with the sequence of the Fc fragment already reported, this establishes the complete amino acid sequence of the C region of the human delta chain and confirms the presence of three C region domains in human IgD. Although the CH1 domains of the five classes of human heavy chains have the expected degree of homology (approximately 30%), the homology of the C delta 1 domains of the human and mouse chains is less than that exhibited by the CH1 domains of other pairs of human and mouse heavy chains. The hinge region of the human delta chain has an unusual structure; the NH2-terminal half has four (or five) GalN oligosaccharides attached, whereas the COOH-terminal half lacks carbohydrate, is dissimilar in sequence, and has a high charge. A computer search verified that the GalN-rich segment has a high degree of identity in sequence with the middle portion of the human C mu 2 domain and that the high-charge segment is related to the same sequence. We propose that the two segments of the human delta hinge have a common evolutionary origin and arose by duplication and independent mutation of a hinge exon derived from the ancestral gene for the C mu 2 domain.

Amino Acid Sequence↗
PubMed1979

Structural studies of human IgD: isolation by a two-step purification procedure and characterization by chemical and enzymatic fragmentation.

A myeloma IgD immunoglobulin (designated WAH) that was present in high concentration in plasma ( approximately 3.5 g/dl) was purified in >90% yield by a two-step procedure of ammonium sulfate precipitation plus AcA 34 gel filtration. Although the plasma had been stored for 2 years without the addition of a proteolytic inhibitor, no "spontaneous" degradation was apparent and the isolated IgD remained structurally intact. However, the purified IgD showed extreme susceptibility in vitro to various proteolytic enzymes; e.g., Fab(delta) (M(r) approximately 47,000) and Fc(delta) (M(r) approximately 80,000) fragments were generated quantitatively after only 10 min of incubation with papain in the absence of cysteine. By combining limited enzymatic digestion, reductive cleavage, and cyanogen bromide fragmentation, several series of well defined fragments corresponding to the different regions and domains of the IgD molecule were generated. These fragments are useful for physical, chemical, and immunological studies, as well as for the sequence determination of the IgD delta chain. A model of the IgD molecule was derived from such studies and from overlapping of the series of fragments. The possible existence of an extra constant domain in the delta chain appears unlikely in view of our finding of an extended hinge region of about 50 residues which can be cleaved off the amino terminus of the papain Fc(delta) by brief treatment with trypsin. In addition to a distinct stretch of carbohydrate attachment sites, the delta-chain hinge region contains a segment unusually rich in electrical charge. This charged segment is responsible for the lability of IgD to spontaneous degradation and may be related to its biological role as a B lymphocyte receptor.

Cyanogen Bromide↗
PubMed1978

Cold pepsin digestion: a novel method to produce the Fv fragment from human immunoglobulin M.

A strategy for the proteolytic fragmentation of human IgM has been developed. This method is called "cold pepsin digestion" because of its unique feature of achieving restricted peptic cleavages at 4 degrees and pH 4.0. Cold pepsin digestion has been applied successfully to produce an Fv fragment from 14 human IgM proteins. The Fv fragment consists of the heavy chain variable domain (VH) and the light chain variable domain (VL) held together by strong noncovalent interaction. Thus, each Fv fragment contains one intact antigen-binding site and represents the minimal active fragment derivable from an antibody molecule. A series of other structurally and functionally important fragments were also isolated and characterized. Two basic digestion pathways were recognized; these mainly reflect the relative accessibility of five sets of major interdomain cleavage sites.

Binding Sites, Antibody↗
PubMedDate not supplied

Localizing individual coronary artery obstructions with the dobutamine stress echocardiography.

The diagnostic accuracy of detecting individual coronary artery lesions using dobutamine stress echocardiography was evaluated in 206 patients with clinical manifestations of agnina pectoris. The sensitivity, specificity, and accuracy in detecting individual coronary artery lesions was described. The sensitivity was higher in the single-vessel group than in the double- or triple-vessel group. Furthermore, the sensitivity of dobutamine stress echocardiography in localizing vascular territories was greater for proximal segment lesions than for distal segment lesions. The increment of total score and score index at peak dose did not reach statistical significance between the left main lesion and the double-vessel lesions of left anterior descending artery and left circumflex artery (4.88 +/- 1.44 vs. 3.79 +/- 0.39, nonsignificant; 0.83 +/- 0.25 vs. 0.54 +/- 0.06, nonsignificant). In conclusion, although dobutamine stress echocardiography is sensitive for diagnosing coronary artery disease, localizing individual coronary artery lesions is less sensitive for triple-vessel disease and distal lesions.

Adult↗
PubMedDate not supplied

Dobutamine stress echocardiography compared with exercise thallium-201 single-photon emission computed tomography in detecting coronary artery disease-effect of exercise level on accuracy.

Dobutamine stress echocardiography (DSE) and exercise thallium-201 single-photon emission computed tomography (SPECT) were compared for the accuracy in detecting coronary artery disease (CAD) in 51 consecutive patients. Twenty-six (group 1) of the 51 patients achieved adequate exercise end points, and 25 (group 2) did not. There were 38 patients with angiographically documented CAD. The overall sensitivity of DSE and thallium-201 SPECT in detecting CAD was 92 and 76% (p = NS), and the specificity was 77 and 77% (p = NS), respectively. The sensitivity of DSE is the same as that of SPECT in group 1 (90 vs. 90%; p = NS) and higher than that of SPECT in group 2 (94 vs. 61%; p < 0.05). In patients with CAD without a history of acute myocardial infarction or pathological Q wave on resting electrocardiogram, the sensitivity of DSE is the same as that of SPECT in group 1 (82 vs. 82%; p = NS) and also higher than that of SPECT in group 2 (90 vs. 40%; p = 0.03). The sensitivity in detecting individual coronary artery lesions with DSE and thallium-201 SPECT was not affected by the exercise level. The agreement between DSE and thallium SPECT in detecting patients with CAD was 88% in group 1 (kappa = 0.69; p < 0.001) and 76% in group 2 (kappa = 0.45; p = 0.01). The agreement in detecting vascular territories with ischemia was 68% in group 1 (kappa = 0.30; p < 0.01) and 75% in group 2 (kappa = 0.33; p < 0.001). The agreement in detecting vascular territories with a scar was 87% in group 1 (kappa = 0.55; p < 0.001) and 85% in group 2 (kappa = 0.44; p < 0.001). In conclusion, the sensitivity and specificity of DSE in detecting CAD are similar to that of thallium-201 SPECT with an exercise level > or =85% of the maximal predicted heart rate. However, in patients who cannot exercise adequately, DSE is more accurate than thallium SPECT. The agreement between DSE and thallium SPECT in detecting patients with CAD and identifying ischemia of individual vascular territories is also affected by the exercise level.

Cardiotonic Agents↗
PubMedDate not supplied

Assessment of the functional significance of coronary artery stenosis by dobutamine-atropine stress echocardiography.

This study was performed to evaluate whether dobutamine stress echocardiography (DSE) can provide any additional information regarding the location and severity of coronary artery disease (CAD) in an individual patient. DSE was performed in 233 patients with clinical manifestations of angina pectoris. There were 162 patients with angiographically documented CAD defined as > or = 50% diameter stenosis. The severity of coronary lesions was divided into three groups: 50-75, 76-90 and >90%. The diagnostic sensitivity in detecting left anterior descending artery (LAD) and right coronary artery (RCA) lesions was higher for lesion severity of>90% than of 50-75% (p = 0.01 for LAD and p < 0.05 for RCA). The diagnostic sensitivity in detecting CAD was highest among patients with proximal coronary lesions (89% for LAD, 64% for the left circumflex artery, and 81 % for the RCA). When lesion severity increased from 50-75 to >90%, wall motion scores at peak dose during dobutamine infusion increased from 12.3 +/- 4.3 to 18.4 +/- 5.4 (p = 0.003) in the proximal LAD lesion group and from 10.6 +/- 2.0 to 20.4 +/- 5.9 (p < 0.0001) in the mid-distal LAD lesion group. When lesion severity increased from 50-75 to >90%, wall motion scores at peak dose increased from 5.9 +/- 2.0 to 8.0 +/- 2.5 (p < 0.05) in the proximal RCA lesion group and from 5.2 +/- 2.1 to 8.1 +/- 1.9 (p < 0.05) in the mid RCA lesion group. However, the change in wall motion scores did not reach statistical significance in proximal and distal lesions of the left circumflex artery when lesion severity increased from 50-75 to >90%. The correlation coefficient between quantitative wall motion score and Gensini's score was 0.54 (p = 0.0001) in all patients and 0.6 (p = 0.0001) in patients without myocardial infarction. In conlcusion, the functional significance of lesion severity and distribution can be evaluated by DSE. Regional dyssynergy of LAD and RCA territories during peak-dose dobutamine infusion was most apparent at the stenotic level >90%.

Atropine↗
PubMedDate not supplied

Comparing the effectiveness of different educational programs for patients with total knee arthroplasty.

PURPOSE: To compare the effects of preadmission and postadmission educational programs for patients with total knee arthroplasty. DESIGN: Quasiexperimental study. SAMPLE: 60 total knee arthroplasty patients. METHODS: Subjects in the experimental group received preadmission preoperative teaching with an instruction booklet during a preoperative outpatient clinic visit. Upon admission to the hospital, they were presented with an educational video tape. The control group received only postadmission preoperative teaching with the same instruction booklet and no video. PREADMISSION AND POSTADMISSION: Preoperative anxiety level, knowledge about postoperative care, exercise performance and postoperative recovery were used as outcome measures. FINDINGS: The research results found: 1. there was no significant difference between the two groups in reduction of preoperative anxiety score: 2. the experimental group had a significantly higher knowledge level than the control group; 3. the experimental group performed exercise more regularly and correctly than those in the control group; 4. the experimental group had greater flexion of the operative knee joint than the control group. CONCLUSION: Preadmission teaching with a videotape program and a health manual for patients with total knee arthroplasty is recommended. IMPLICATIONS FOR NURSING RESEARCH: More indicators such as postoperative pain and patient satisfaction can be used to investigate the effectiveness of intervention. In addition, increasing the sample size is recommended for future studies.

Aged↗