Biomedical subjects

M C Lee

Publications and source records attributed to M C Lee.

At least 235 records · Page 13Linked to original sources

PubMed1993

Radioimmunoscintigraphy of advanced gastrointestinal carcinomas employing I-131 labeled CEA-79 monoclonal antibody.

CEA-79 is a murine IgG2a type monoclonal antibody (MoAb) generated using purified CEA from culture supernatants of a human colon cancer cell line, LS174T. The association constant and immunoreactivity of the I-131 labeled CEA-79 ranged from 2.0 to 3.2 x 10(9) l/mole, and from 54 to 74%, respectively. The purpose of this study was to evaluate the feasibility of radioimmunoscintigraphy employing MoAb CEA-79 in patients with advanced gastrointestinal carcinomas. Two mgs of MoAb CEA-79 was labeled with 111 MBq (3 mCi) of I-131, and infused intravenously in 6 stomach cancer and 16 colon cancer patients. Out of 6 patients with stomach cancer, immunoscintigraphy was able to detect the tumors in 4 cases. However, immunoscintigraphy found out tumors in all patients with colon cancer. Moreover, 1 patient with stomach cancer and 2 patients with colon cancer showed increased uptake of MoAb in the tumor lesions despite normal serum levels of CEA. We could conclude that this antibody has a potential as a new imaging agent for the diagnosis of gastrointestinal carcinoma.

Adult↗

PubMed1993

The development of general practice in China.

The concepts and principles of general practice are consistent with Chinese cultural values; the leading authorities at the General Practice Training Centre are extremely enthusiastic about the general practice movement; the Ministry of Public Health is totally supportive of the general practice training; the medical/allied health professionals are eager to participate in general practice activities; and general practice certainly is responsive to public expectations. General practice will be flourishing and prosperous in China; however, there may be times when the specialty of general practice in China experiences growing pains with obstacles. The experiences gained from the development of general practice training programmes in Taiwan and other countries to handle the obstacles are of tremendous value to the development of general practice in China. It is expected that communication and exchange between the general practice educators of Taiwan and China will play an important role in the further development of general practice in China.

China↗

PubMed1993

Isolated or predominant ocular motor nerve palsy as a manifestation of brain stem stroke.

BACKGROUND AND PURPOSE: There have been few reports of strokes producing isolated or predominant ocular motor nerve palsies as a clinical manifestation. METHODS: We studied seven patients with brain stem stroke who had ocular motor palsies as the only or the predominant neurological manifestation, and we correlated their clinical features with radiological findings. RESULTS: Five patients had small strokes in the area of oculomotor nuclei or fascicles and showed various combinations of oculomotor disturbances. Three of these patients showed vertical gaze paresis of the opposite eye. One patient with a small hemorrhage near the aqueduct of Sylvius showed fourth nerve palsy on the contralateral side, and a patient with a small infarct in the pontine tegmentum showed isolated sixth nerve palsy. Nonocular minor neurological signs included trigeminal sensory changes in four patients and clumsy arm in two. Ocular and nonocular dysfunctions generally improved within several months. Radiological findings of the brain stem correlated well with the ocular signs. CONCLUSIONS: We conclude that acute brain stem stroke should be included in the differential diagnosis of isolated ocular motor nerve palsies and that appropriate diagnostic investigations should be performed in these cases.

Adult↗

PubMed1993

Coxiella (Q fever)-associated myelopathy.

We describe six men with a slowly progressive myelopathy characterized by asymmetric, incomplete spinal cord syndrome manifested with a thoracic sensory level, mild spastic paraparesis, and urinary incontinence. The spinal cord lesions were evident by MRI in four of them. Coxiella burnetii infection was confirmed in the blood of all patients by immunofluorescence microscopic assay (IFA) and transmission electron microscopy (TEM). In two patients, we detected C burnetii by TEM and IFA using CSF from the patients inoculated onto fresh peripheral blood lymphocyte. Four patients, treated with appropriate antibiotics, responded either with partial resolution of symptoms or arrest of further neurologic progression. In three, the MRI lesions decreased in size.

Adult↗

PubMed1993

Malignant mixed müllerian tumor of the ovary: report of a case and review of the literature.

Malignant mixed Müllerian tumors (MMMTs) have been reported to occur in the female genital tract, especially in the uterine corpus. However, MMMT of the ovary is very rare and to best knowledge, no previous case has been reported in the literature of Taiwan. A 63-year-old female, with unique MMMT of the ovary, is described as having tumor with both carcinomatous and sarcomatous elements. The carcinomatous component was mainly composed of undifferentiated carcinoma. Small foci of glandular or papillary differentiation could be found. The sarcomatous component was composed of islands of atypical cartilaginous elements. Immunohistochemical studies revealed carcinomatous and heterologous sarcomatous elements respectively. Carcinomatous elements were cytokeratin and epithelial membrane antigen (EMA) positive, whereas heterologous sarcomatous elements were vimentin and S-100 positive. The patient received a left salpingo-oophorectomy and omentectomy without further chemotherapy or radiotherapy. The patient, already in the advanced stage, expired one month after the initial diagnosis.

Female↗

PubMed1993

Clinical immunoscintigraphy of ovarian carcinoma using iodine-131-labeled 145-9 monoclonal antibody.

The monoclonal antibody (Mab) designated 145-9 recognizes CA125 antigen but binds to a different epitope than that recognized by OC125 antibody. This is a clinical study assessing the safety, kinetics and imaging sensitivity of Mab 145-9. Two milligrams of Mab were labeled with 111 MBq (3.0 mCi) of 131I and infused intravenously in 18 patients with ovarian carcinoma. Immunoscintigraphies were done at three, five, and seven days. There were no adverse reactions to the injection of this Mab. All immunoscintigraphies were considered positive. Immunoscintigraphy detected tumor lesions were confirmed in operative fields, in two patients with normal serum levels of CA125 and in four patients whose sonography and/or x-ray computed tomography showed negative findings. In five patients, immunoscintigraphy was repeated without any adverse reaction and revealed the progress of the carcinoma. Pharmacokinetic studies showed the steady-state volume of distribution (Vdss) to be 2772 +/- 466 ml (mean +/- s.d.), and clearance 51.3 +/- 12.7 ml/hr. In summary, immunoscintigraphies using 131I-labeled Mab 145-9 were done safely in patients with ovarian carcinoma. Preliminary results reveal a high sensitivity compared to radiological methods and tests currently in use.

Adult↗

PubMed1992

Vasodilator effect of scoparone (6,7-dimethoxycoumarin) from a Chinese herb.

A possible mechanism of the vasodilator effect of scoparone was investigated. Scoparone (10(-6)-3 x 10(-5) M) dilated rat aortic rings precontracted with phenylephrine in a dose-dependent manner. The presence of endothelium facilitated the vasodilator effect. Scoparone depressed the contractile responses to phenylephrine and serotonin, but not that to potassium chloride. Both the vasoconstriction and O2- production induced by alloxan, a diabetogenic compound, were depressed by scoparone. It appears that scoparone exhibited a free radical scavenger-like effect. The dilatation elicited by acetylcholine was potentiated by scoparone. The dilator activity of scoparone was markedly inhibited by methylene blue and hemoglobin, guanylate cyclase inhibitors. Furthermore, the basal guanosine 3',5'-cyclic monophosphate (cGMP) level was elevated in the presence of scoparone. The dilator activity of scoparone was also inhibited by quinacrine (inhibitor of phospholipase A2) and indomethacin (inhibitor of cyclooxygenase). Our results showed further that the output of 6-keto-prostaglandin F1 alpha, a stable metabolite of prostacyclin, was enhanced by scoparone. It is suggested that the vasodilator effect of scoparone in rat aorta may be mediated through the enhancement of prostacyclin release, protecting against EDRF inactivation, and activating guanylate cyclase.

Animals↗

PubMed1992

Two nucleotides next to the anticodon of cytoplasmic rat tRNA(Asp) are likely generated by RNA editing.

The nucleotide sequences of major cytoplasmic tRNA(Asp) from rat liver and rat ascites hepatoma comprise a U32 and C33 next to the anticodon as was confirmed by different procedures. Additionally we identified a tRNA(Asp) with C32 and U33 in a minor proportion. We have shown earlier that the tRNA(Asp) gene is part of a cluster of tRNA genes which is amplified at least ten times in the rat nuclear genome. Six independent isolated clones display identical sequences in the coding region of the tRNA(Asp) gene which differ from tRNA(Asp) in having C32 and T33. Using a combination of single-strand conformation polymorphism (SSCP) analyses and direct sequencing of polymerase chain reaction (PCR) products we have now demonstrated that no variant allele of the tRNA(Asp) gene with T32 and C33 exists in the rat genome. Together with the RNA sequencing data these findings strongly indicate that major rat tRNA(Asp) is generated by post-transcriptional pyrimidine transitions at positions 32 and 33 and that the minor tRNA(Asp) is its unedited precursor.

Animals↗

PubMed1992

Nucleotide sequence of cDNA for Acacia confusa trypsin inhibitor and implication of post-translation processing.

Synthetic oligonucleotides corresponding to all possible sequences of N-terminal and C-terminal region of Acacia confusa trypsin inhibitor were used to generate ACTI-related sequences using the polymerase chain reaction on the cDNAs encoding ACTI of the seeds of legume, A. confusa. The deduced amino acid sequence agreed with that determined by the peptide analysis except an extra amino acid residue, serine, was found at the junction of A and B chain, which was removed by post-translation processing with specific protease(s). The substrate specificity of the protease(s) was found to cleave at the C-terminal sites of asparagine and serine, which was also shown to be the same case for another plant protein, abrin, isolated from legume, Abrus precatorius.

Acacia↗

PubMed1992

Comparison of bone mineral content among Japanese, Koreans, and Taiwanese assessed by dual-photon absorptiometry.

Throughout the world the diagnosis and management of osteoporosis currently involves the measurement of bone mineral content. There are, however, no studies comparing bone mineral content among Asian people. This cross-sectional study was designed to quantify spine and femur bone mineral density (BMD) in Japanese and compare BMD among Asian people (Japanese, Koreans, and Taiwanese) using the same model dual-photon system (Norland Model 2600). Following a peak BMD in the third and fourth decades, the Japanese BMD values of the lumbar spine and femoral neck showed a clear decrease (annual loss of 0.99 and 0.74%, respectively) with age in females. On the other hand, Japanese BMD values were stable in males until the fifth decade. There was some decrease in BMD with age after the fifth decade, which was much less obvious than that in females. An age-dependent loss of BMD was clearly observed in Japanese and Korean but not in Taiwanese females. Korean males seemed to have a clearer age-dependent loss of BMD compared to Japanese males. Our findings indicate that differences may exist in the BMD of Asian people and that in addition to the quantitative determination of individual BMD, dual-photon absorptiometry may be useful for the comparison of BMD among different ethnic and cultural groups.

Absorptiometry, Photon↗

PubMed1992

One-stage operation for treatment after delayed diagnosis of thoracic esophageal perforation.

Perforation of the thoracic esophagus can be fatal unless diagnosed promptly and treated effectively. The high mortality with delayed treatment is due principally to an inability to effectively close the perforation and prevent leakage. From 1982 to 1988, 7 consecutive patients (aged 16 to 73 years) were treated after a delayed diagnosis (26 hours to 25 days) of thoracic esophageal perforation. In all patients, the perforation was closed after debridement with total exclusion of the esophagus (T-tube cervical esophagostomy plus absorbable ligatures applied to the esophagogastric junction and the cervical esophagus distal to the esophagostomy). Radical decortication and wide mediastinal and pleural drainage were also done. Nutritional supply was given through a feeding gastrostomy. Antibiotics were administered according to the results of cultures. All patients survived. Continuity of the esophagus was established by removal of the T tube and spontaneous absorption of the ligatures. Endoscopy and esophagography performed 4 weeks after the initial operation showed a well-healed esophagus without stenosis or leakage in all patients. No secondary thoracotomy or esophageal reconstruction was necessary. No dysphagia was noted during follow-up (range, 12 to 50 months; mean follow-up, 23 months). We conclude that primary closure of the perforation and total esophageal exclusion with the use of absorbable ligatures and T-tube esophagostomy can provide a one-stage operation with good results for repair of thoracic esophageal perforation diagnosed late.

Adolescent↗

PubMed1992

Strain rate effects on tensile failure properties of the common carotid artery and jugular veins of ferrets.

We have recently reported the insensitivity of tensile failure properties of human cerebral bridging veins to strain rate. Due to data scattering, however, concerns remain regarding this finding. To pursue the issue further, the common carotid arteries and external and internal jugular veins from seven ferrets were stretched longitudinally in vitro at either a low strain rate of 0.2-2.0 s-1 or a high rate of approximately 200 s-1. The ultimate stretch ratios and loads were found to be independent of strain rate in all the vessels tested. Therefore, the present results appear to support our previous finding on human bridging veins.

Animals↗

PubMed1992

Effects of posts on dentin stress distribution in pulpless teeth.

A finite element analysis was carried out to study the roles of posts in reducing dentin stress in pulpless teeth. Two-dimensional plane strain models of the midlabiolingual section of a human maxillary central incisor were first analyzed. The results showed that the gold alloy post reduced maximal dentin stress by as much as 30%. However, the integrity of the dentin was compromised and the effects of the post were likely to be exaggerated in such models. In an effort to correct for these problems, plane stress models with side plates and axisymmetric models were analyzed. Posts were found to reduce maximal dentin stress by only 3% to 8% when the teeth were subjected to masticatory and traumatic loadings in these latter models. Although posts reduced maximal dentin stress by as much as 20% when the teeth were loaded vertically, teeth such as incisors and canines normally are not subjected to vertical loadings. Thus the reinforcement effects of posts seem to be doubtful in these teeth.

Bite Force↗

PubMed1992

IgG1, IgG2 and IgM responses to two Haemophilus influenzae type b conjugate vaccines in young infants.

PRP-meningococcal outer membrane protein complex (PRP-OMPC) and oligosaccharide linked to variant diphtheria toxin (HbOC) Haemophilus influenzae type b (HIB) conjugate vaccines have both been licensed for United States infants at 2 months of age. Differences in serologic responses for these vaccines have been noted with PRP-OMPC producing an early response at 2 months of age and HbOC producing a higher response after a third dose at 6 months of age. To further characterize the nature of these distinct responses, we measured the IgG1, IgG2 and IgM anti-HIB concentrations by enzyme-linked immunosorbent assay after administration of both vaccines. PRP-OMPC produced an IgM and IgG1 anti-HIB response following the initial dose at 2 months of age. After two doses of HbOC an increase in IgG1 and IgM were noted and after a third dose at 6 months of age an IgG2 anti-HIB response occurred. In addition 33 study subjects were boosted with PRP-OMPC at age 18 months and compared with 34 subjects who received only a primary dose. The anti-HIB IgG1 and IgG2 concentrations following the booster dose were both significantly higher for the primed group (P = 0.0001 and P = 0.001, respectively). Both HIB conjugate vaccines produce predominantly IgG1 anti-HIB antibody responses. The early response to PRP-OMPC vaccine at 2 months of age may result from adjuvant characteristics of the OMPC.

Antibodies, Bacterial↗

PubMed1992

Spasmodic torticollis: medical and botulinum A toxin treatment.

The exact pathophysiologic mechanisms of spasmodic torticollis and other idiopathic torsion dystonias remain largely unknown. Thus, a variety of drugs have been used alone or in combination on an empirical basis to treat these disorders, but to date none have efficacy that is proven and consistent. The drugs in use include anticholinergics, benzodiazepines, dopaminergics and dopamine antagonists with variable degrees of clinical improvement. Botulinum toxin A injection treatment for spasmodic torticollis is safe and efficacious with minimal adverse effect. However, it is expensive and beneficial effects are short-lasting. Only when a spasmodic torticollis patient's symptoms are refractory to combined treatment, using various drugs and Botulinum toxin injections, should the patient be considered a candidate for neurosurgical procedures.

Benzodiazepines↗

PubMed1992

Premenstrual tension syndrome with periodic bulimia nervosa: report of a case and review of the literature.

Premenstrual tension syndrome (PMS) is well known in its epidemiology, etiology, symptomatology and treatment. However, PMS characterized by bulimic episodes is rare. We report a case of a 20-year-old university student who suffered from uncontrollable binge eating premenstrually for six months before visiting our clinic. She was obese without any other notable family or medical history except the PMS noted for two years. A daily food diary for two consecutive menstrual cycles showed that the mean differences in caloric intake between premenstrual and postmenstrual days of two menstrual cycles were 679 and 703 calories, respectively. The greater peaks in caloric level were noted within the third to fifth days prior to the onset of menstruation. All binge episodes occurred in the premenstrual period, especially within five days prior to menstruation. In this report, we will also review the literature on the relationship between PMS and dietary intake, as well as bulimia nervosa.

Adult↗

PubMed1992

Detection of extrapulmonary tuberculosis with gallium-67 scan and computed tomography.

We evaluated 23 patients with extrapulmonary tuberculosis (TB) with 67Ga imaging to assess its usefulness in the diagnosis of this condition. We performed computed tomography (CT) in 17 patients to assess CT features of extrapulmonary TB in comparison with findings from 67Ga scans. Nineteen of 23 patients (83%) had positive findings on 67Ga scans. One of five patients with tuberculous mediastinal lymphadenopathy, two patients with cervical lymphadenitis and a patient with renal TB had negative 67Ga scans. It was observed that the detection of previously unrecognized primary foci of TB, without concomitant pulmonary TB, was possible using 67Ga imaging in five patients (22%). The 67Ga scan was relatively sensitive for the localization of extrapulmonary TB. It is suggested that the 67Ga scan could serve as a screening method, when followed by CT and ultrasonography, for the initial detection of occult tuberculous lesions, especially in patients with prolonged fever.

Adult↗

PubMed1991

Evaluation of the protective effect of verapamil on reperfusion injury by 111In anticardiac myosin antibody in canine myocardial infarction.

We quantitated the protective effect of verapamil on reperfusion injury in canine myocardial infarct using 111In-anticardiac myosin antibody and correlated to the electronmicroscopic findings. Experimental myocardial infarction was performed by one hour occlusion of the anterior descending coronary artery and followed by reperfusion. Saline or verapamil (0.6 mg/kg/hr) was started at 40 minutes after coronary artery occlusion and continued throughout the experiment. There was an inverse exponential relationship between anticardiac myosin uptake and regional coronary blood flow in both the control (r = -0.86) and the verapamil treated (r = -0.71) groups. Less uptake of 111In-anticardiac myosin antibody was observed in the verapamil treated group than in the control group of the regions where blood flow was lower than 30% of normal. In the control group, the myocardium showed signs of the typical contraction band necrosis. In the verapamil treated group, however, the myocardium contained fewer electron dense granules and mild degree of contraction bands.

Animals↗