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Biomedical subjects

M C Lee

Publications and source records attributed to M C Lee.

At least 181 records · Page 10Linked to original sources
PubMed1997

Effect of the distraction rate on the activity of the osteoblast lineage in distraction osteogenesis of rat's tibia. Immunostaining study of the proliferating cell nuclear antigen, osteocalcin, and transglutaminase C.

The purpose of this study was to investigate kinetics of the osteoblast lineage in the periosteum and endosteum according to different distraction rates in distraction osteogenesis of rat's tibia. An osteotomy was performed on 144 rats at the proximal diaphysis of the left tibia. The lengthening process was started after a latency period of 3 days, with varying distraction rates of 0.25 mm (group I), 0.5 mm (group II), 0.75 mm (group III), 1.0 mm (group IV) and proceeded until a 3.5 mm length gain was achieved. The animals that had an osteotomy alone, without lengthening, served as a control (group V). Immunohistochemical staining of proliferating cell nuclear antigen (PCNA), osteocalcin, and transglutaminase C (TGase C) were done on the four animals in each group sacrificed at post-distraction days 1, 3, 5, 7, 14, and 28 in order to observe the temporal changes among the experimental and control groups. Also, in order to compare the staining rates at a given length gain among the groups, animals in each group were additionally sacrificed 2 days post-distraction in group II; 2 and 4 days in group III; and 1.5, 2 and 2.5 days in group IV. The results of the expression rates of PCNA, osteocalcin, and TGase C in each group were analyzed quantitatively. The immunohistochemical study on callotasis of rat's tibia revealed that the osteoblast lineage in the periosteum is more activated than that in the endosteum for proliferation and differentiation by distraction, suggesting that the periosteum plays a more important role in neoosteogenesis in the distraction gap. Daily distraction rates ranging from 0.25 mm to 0.75 mm in two increments is appropriate for successful distraction osteogenesis of rat's tibia, but the rate of 0.25 mm a day is significantly better than that of 0.75 mm as was made evident in the immunohistochemical observations.

Animals↗
PubMed1997

Clinical significance of hepatic visualization on iodine-131 whole-body scan in patients with thyroid carcinoma.

UNLABELLED: The purpose of this study was to evaluate the frequency and clinical significance of diffuse hepatic uptake on 131I whole-body scan in 399 patients (53 males, 348 females) with well-differentiated adenocarcinomas of the thyroid. METHODS: Two hundred and ninety-one diagnostic scans were performed 2 days after the administration of 74-370 MBq (2-10 mCI) 131I, and 824 post-therapy scans were done 3-5 days after the administration of 1.11-7.4 GBq (30-200 mCI) 131I. There was no evidence of liver metastasis in these patients. Liver and thyroid visualization on each 131I scan were graded from 0-4. To evaluate the incorporation of radioiodine to thyroglobulin and thyroid hormones, a patient's serum was extracted by 80% ethanol/20% trichloroacetic acid solution and analyzed by silica gel thin-layer chromatography. RESULTS: Diffuse hepatic uptake (> Grade 2) was definitely seen in 239 of 399 (59.9%) of the patients and 397 of 1115 (35.6%) of the studies. In the diagnostic scans, 36 (12.0%) showed uptake in the liver. In post-therapy scans, however, the incidence of liver uptake increased according to increased doses of 131I (39.1% with 1.11 GBq, 61.5% with 2.775-3.7 GBq and 71.3% with 5.55-7.4 GBq). The more that uptake appeared in the residual thyroid, the more it appeared in the liver. There were 13 patients whose scans showed metastatic and liver uptake without any thyroid uptake. Fifteen patients showed diffuse liver uptake without uptake by the thyroid or metastasis. Follow-up studies of seven of these patients revealed metastatic lesions. Liver uptake on scan related to the fraction of 131I-labeled thyroglobulin in the serum. CONCLUSION: Diffuse liver uptake indicated functioning thyroid remnant or metastasis. In a few cases, liver uptake without uptake by the thyroid or metastasis on whole-body scans suggests hidden metastases.

Adenocarcinoma↗
PubMed1997

Characteristics of adolescent patients and their health problems at an adolescent health clinic.

In Taiwan, there has been an increase in biopsychosocial morbidity among adolescents in the past ten years, but neither an adolescent health care delivery system nor a subspecialty training program in adolescent medicine has been hitherto established. To better understand the characteristics of adolescent patients and their health problems, the sociodemography and health problems of all adolescent patients aged 11 to 21 years who visited the Adolescent Health Clinic twice or more during January, 1994 and December, 1995 at a college hospital, were analysed by reviewing patients' medical records and the adolescent registration records. There were totally 264 adolescent patients with an average age of 18.7 +/- 3.4 years. The number of female adolescents involved in the study (139 persons or 52.7%) was little more than that of male adolescents. Most of the adolescent patients (67.4%) were in late stage of adolescence; in addition, most of them (81.4%) were students. During the 2-year study period, there was a total of 350 independent health problems among 957 office visits made by the 264 patients, averaging 1.3 problems and 2.7 office visits per patient and per problem, respectively. Supplementary classification, mental disorders, and respiratory system diseases were the three leading disease classifications, occupying 66.6% of all disease classifications. General medical examination, upper respiratory tract infection, and immunization were more common among all individual diagnoses. Regarding gender difference in the encountered health problems, hepatitis B, office visiting for counseling, and conductive disorder, were more prominent in the male adolescents, whereas upper respiratory tract infection, goiter, acne vulgaris, peptic ulcer disease, migraine, and eating disorders were more common in the female adolescents. Moreover, the patients in the different stages of adolescence had their unique health problems. It was concluded that there were variations in the health problems encountered among adolescents of different genders and of the different stages of adolescence.

Adolescent↗
PubMed1997

Imaging and quantitation of dopamine transporters with iodine-123-IPT in normal and Parkinson's disease subjects.

UNLABELLED: Iodine-123-N-(3-iodopropene-2-yl)-2beta-carbomethoxy-3beta-( 4-chlorophenyl) tropane (123I-IPT) is a new dopamine transporter ligand that selectively binds the dopamine reuptake sites. Transporter concentrations have been known to decrease in Parkinson's disease patients. The purpose of this study was to evaluate the usefulness of IPT as an imaging agent for measuring changes in transporter concentrations in Parkinson's disease. METHODS: IPT labeled with 6.78 +/- 0.67 mCi 123I was injected intravenously as a bolus into eight normal controls (mean age 41 +/- 12 yr) and 17 Parkinson's disease patients (mean age 55 +/- 9 yr). Dynamic SPECT scans of the brain were then performed for 5 min each over 120 min on a triple-headed gamma camera equipped with medium-energy collimators. Regions of interest were drawn on the middle set of the image at the level of the basal ganglia (BG) for each subject. Time-activity curves were generated for the left BG, right BG and occipital cortex (OCC). The empirical ratios between BG-OCC and OCC, which represent specific-to-nonspecific binding ratios, were computed at various time points. The statistical parameter k3/k4 was estimated by two methods: a variation of the graphic method that derives the ratio of ligand distribution volumes (R[V]) and the area ratio method (R[A]), in which the ratio is calculated from the areas under the specific and nonspecific binding activity curves. RESULTS: The mean (BG-OCC)/OCC ratio for normal controls (3.07 +/- 0.73) was significantly higher than that for Parkinson's disease patients at 115 min (1.10 +/- 0.56) (p = 2.76 x 10[-5]). The mean R(V) and R(A) for normal controls were 2.06 +/- 0.27 and 1.50 +/- 0.15, respectively. The mean R(V) and R(A) for Parkinson's disease patients were 0.78 +/- 0.31 and 0.65 +/- 0.24, respectively. Both R(V) and R(A) for normal controls were significantly higher than those for Parkinson's disease patients (p values for R(V) and R(A) were 1.91 x 10(-8) and 3.46 x 10(-10), respectively). The R(V) has linear relationships with both R(A) and (BG-OCC)/OCC ratio at 115 min. The R(V) has a higher correlation (r = 0.99) with R(A) than it does with (BG-OCC)/OCC (r = 0.93). CONCLUSION: The R(V), R(A) and (BG-OCC)/OCC for Parkinson's disease patients were clearly separated from those of normal controls, and they may be useful outcome measures for clinical diagnosis. The simplest (BG-OCC)/OCC ratio, requiring a single late time point, could be useful in clinical situations, whereas R(V) or R(A) is preferred when the dynamic data are available. The findings suggest that 123I-IPT is a useful tracer for diagnosing Parkinson's disease and studying dopamine reuptake sites.

Adult↗
PubMed1996

Disappearance of essential tremor after small thalamic hemorrhage.

Stereotactic thalamotomy has been reported to be effective in the control of various tremors, including essential tremor. We report a 69-year-old female who experienced spontaneous thalamotomy with a small thalamic hemorrhage, resulting in disappearance of essential tremor on the contralateral side to the hematoma, which involved the nucleus ventralis intermedius (Vim) of the thalamus and a portion of the posterior limb of the internal capsule.

Aged↗
PubMed1996

Quantitative lung perfusion scintigraphy in postoperative evaluation of congenital right ventricular outflow tract obstructive lesions.

Improved methods to relieve pulmonary artery stenosis have emphasized the need for an accurate noninvasive method to quantify the pulmonary blood flow. The aim of this study was to compare the roles of Tc-99m MAA perfusion lung imaging, chest x-ray, MRI, and cine-angiography for postoperative evaluation of pulmonary blood flow in patients with congenital right ventricular outflow tract (RVOT) obstructive lesions. Eleven patients underwent chest x-ray, MRI, perfusion lung imaging, and cine-angiography after corrective surgery of RVOT obstruction. The perfusion ratio on lung scans was calculated on the posterior views. The correlation coefficient of the left to right perfusion ratio measured by lung scans obtained with that by visual assessment of chest x-rays, with the most stenotic diameter ratio on MRI and on angiography being 0.57, 0.88 (P < 0.001), and 0.87 (P < 0.001), respectively. Follow-up perfusion lung scans in seven patients, before and after pulmonary artery intervention showed significantly improved perfusion ratios (0.30 +/- 0.11 to 0.70 +/- 0.22; P < 0.001), which were concordant with the clinical findings. The authors conclude that the quantitative perfusion lung scan is the noninvasive method of choice for postoperative evaluation of the pulmonary artery in congenital RVOT obstruction.

Adolescent↗
PubMed1996

Adaptations of ligamentum teres in ischemic necrosis of human femoral head.

Little is known about the biomechanical properties of human ligamentum teres. To more fully understand the ligamentum teres, its dimensions and mechanical properties were measured in 22 cases of acute fracture of the femoral neck and 21 cases of ischemic necrosis of the femoral head. The specimens first were preconditioned and then loaded to failure with a testing machine at a fast strain rate of 100% s(-1). The ischemic necrosis group had a significantly larger volume (3.09 +/- 1.81 ml versus 1.30 +/- 0.62 ml) and cross section area (65.3 +/- 59.1 mm2 versus 30.6 +/- 27.2 mm2) than did the acute fracture group. The former also had a significantly greater ultimate load (234 +/- 168 N versus 130 +/- 111 N) and strain energy to failure (1.22 +/- 1.04 J versus 0.41 +/- 0.39 J), but a significantly smaller linear modulus (4.72 +/- 3.31 MPa versus 8.69 +/- 7.97 MPa) than did the latter. Histologic studies showed differences in the amount of organized collagen and components of subsynovial tissue between the 2 groups. Mechanical and morphologic adaptations of the ligamentum teres in a group of ischemic femoral heads are described, and a possible biomechanical role is suggested for the ligamentum teres in the hip joint in conjunction with the ischemic necrosis of the femoral head.

Adaptation, Physiological↗
PubMed1996

Lipoma of the parotid gland.

We report two cases of lipoma of the parotid gland which present as a non-tender, freely movable and intraparotid mass. Lipomas are common soft tissue neoplasms but found very rarely in the parotid gland, and so are often not considered in the initial differential diagnosis of parotid gland tumor. We believe that these tumors are cured by simple excision, and thus superficial parotidectomy is enough for treatment.

Adult↗
PubMed1996

Bone marrow scintigraphy using technetium-99m-antigranulocyte antibody in hematologic disorders.

UNLABELLED: Bone marrow is the primary site for many hematologic disorders. To date, however, no suitable bone marrow imaging method has been found. The present study investigates the usefulness of bone marrow immunoscintigraphy using 99mTc-labeled antigranulocyte antibody (anti-NCA-95) in 31 patients with hematologic disorders. METHODS: One milligram of antibody labeled with 259-370 MBq 99mTc was injected intravenously, and bone marrow images were taken 4 hr later. We also calculated the uptake ratios of lumbar bone marrow-to-background (L/B) and ilium-to-background (I/B). RESULTS: Of 15 patients with aplastic anemia, 7 showed diffusely decreased antibody uptake (L/B = 2.3 +/- 0.8, I/B = 3.0 +/- 0.8) compared to control patients (n = 21, L/B = 8.2 +/- 2.5, I/B = 10.3 +/- 3.1) Six patients had both decreased and increased uptake areas and two had normal to slightly increased uptake. Of those patients receiving various types of therapy for aplastic anemia, all but one showed increased or irregular uptake. The degree of antibody uptake in the bone marrow correlated with peripheral blood analyses (hemoglobin, white blood cells, platelets). Of six patients with myelodysplastic syndrome, four had irregular uptake and two diffusely decreased uptake. Four patients with myelogenous leukemia showed normal uptake, whereas two with lymphocytic leukemia had decreased uptake. Patients with iron deficiency anemia, pure red cell aplasia or thalassemia minor exhibited normal uptake with bone marrow expansion. CONCLUSION: Immunoscintigraphy with antigranulocyte antibody is a useful method for evaluating the bone marrow status of patients with various hematologic disorders.

Adolescent↗
PubMed1996

Intestinal leakage of technetium-99m-MDP in primary intestinal lymphangiectasia.

We present a case in which a patient with primary intestinal lymphangiectasia demonstrated abnormal intestinal accumulation of tracer during 99mTc-methylene diphosphonate (MDP) skeletal scintigraphy. Early intestinal leakage with gradual colonic migration and concentration was confirmed by repeat bone scan with serial acquisitions. The mechanism for the intestinal localization of 99mTc-MDP seen in this patient is not clear. Thus, intestinal lymphangiectasia can be a cause for extra-osseous localization of bone scan agents in the intestine.

Adult↗
PubMed1996

Maternal and child health services provided by the family physicians in a college hospital.

Traditionally, maternal and child health services in Taiwan have been offered mainly by the public community health station in each township. There is a trend to integrate these services into the daily practice of physicians in varied medical settings. The purpose of this study was to evaluate the work of providing the maternal and child health services by family physicians practicing at a college hospital. From July 1993 through June 1994, 69 women attending the pre-marital health examination program and 399 family patients who were in need of the maternal and child health services at the Family Medicine Clinic were included in this study. Data related to subjects' backgrounds and office visits were analyzed retrospectively. About 80% of patients attending pre-marital health examinations were satisfied with the scope and process of the services provided. Of 399 family patients contacted by letter and telephone, 322 patients (80.7%) kept the appointments to visit our clinic. Regarding maternal health services, related health education and counselling services were widely provided to female family patients. However, the actual implementation rates of breast examination, Pap smear test and family planning procedures were only 44.5%, 35.7%, and 23.2%, respectively. Factors related to female patients' agreement to do breast examination or Pap smear test included their educational level, age, duration of being enrolled in family care, and the number of family members under the family care. Regarding child health services, vaccinations and periodic health examinations were the main services provided by the family physicians. We concluded that family physicians in our series are capable of providing maternal and child health services to their family patients, and that the actual implementation rates of preventive services could be further promoted through family physicians' more active attitude and recruiting methods.

Adolescent↗
PubMed1996

Complete resolution of diastolic mitral regurgitation in chronic, but not acute aortic regurgitation after aortic valve replacement--a transesophageal echocardiography study.

A 65-year-old male was admitted with progressive dyspnea on exertion. Severe aortic regurgitation (AR) had been disclosed by transthoracic echocardiography 10 mon previously. Aortic valve replacement was proposed and intraoperative transesophageal echocardiography on color Doppler imaging revealed severe aortic regurgitation, moderate global hypokinesis of the left ventricle and mild-to-moderate diastolic mitral regurgitation. The regurgitant jet was seen to pass through the posterior mitral leaflet in a direction toward the center of left atrium. Mitral valve perforation was suspected. But mitral valve was found to be intact after a thorough exploration. Surgery proceeded uneventfully and diastolic mitral regurgitation was resolved completely after the aortic valve was successfully replaced. Diastolic mitral regurgitation has been reported to be closely related to acute AR, but the picture differs somewhat from the present example. The possible cause for this disease presentation is to be further investigated.

Aged↗
PubMed1995

Gangliosides have a bimodal effect on DNA synthesis in U-1242 MG human glioma cells.

GM1, GD1a, and GT1b inhibit both PDGF-stimulated and serum-stimulated DNA synthesis in Swiss 3T3 cells and the human glioma cell line U-1242 MG in a dose-dependent manner. The ganglioside inhibitory effect is counteracted in a dose-responsive fashion by serum such that ganglioside-induced inhibition is essentially abolished in 10% serum. Because of the potentially important role that gangliosides play in growth regulation of human gliomas, this phenomenon was studied in detail using U-1242 MG cells. Stimulation of DNA synthesis by low doses of serum in U-1242 MG cells is inhibited in a dose-responsive fashion by ganglioside GM1. However, serum itself counteracts the inhibitory effect of ganglioside in a dose responsive way. Kinetic analyses demonstrate that GM1 competes with some components of serum for sites on U-1242 MG cells (Kb of GM1 = 12.5 microM). On the other hand, GM1, GD1a, and GT1b stimulate DNA synthesis in quiescent U-1242 MG cells in both sparse and confluent conditions, indicating that ganglioside-stimulated DNA synthesis is dependent on the phase of cellular growth rather than cellular density. This growth stimulatory effect of gangliosides is more potent on quiescent, confluent cells than quiescent, sparse cells. These results demonstrate that exogenously added gangliosides can have opposite (bimodal) effects on progression of human glioma cells through the cell cycle depending upon the growth phase of the cells.

Cell Line↗
PubMed1995

Reversible parkinsonism and dystonia following probable mycoplasma pneumoniae infection.

Infectious disease is a rare cause of parkinsonism. We report a 7-year-old boy who developed flu-like symptoms followed by parkinsonian features including hypophonia, hypomimia, bradykinesia, and dystonia. A T2-weighted brain magnetic resonance imaging showed high signal intensities in both basal ganglia. The results of serial serologic tests of Mycoplasma pneumonia antibody suggest that this movement disorder was associated with Mycoplasma pneumonia infection. The patient's symptoms gradually resolved, and the basal ganglionic lesions disappeared on follow-up magnetic resonance imaging.

Basal Ganglia↗
PubMed1995

Concentration and distribution of tumor associated antigens TAG-72 and CEA in stomach cancer.

We measured the concentration and distribution of tumor associated antigens, TAG-72 and CEA, in stomach cancer by in vitro quantitative autoradiography (IV-QAR). Frozen sections of 33 specimens were incubated with varying concentrations of 125I-labeled CEA-79.1 and B72.3 antibodies specific for carcinoembryonic antigen (CEA) and tumor-associated glycoprotein-72 (TAG-72), respectively. Computer analysis of specific antibody binding gave maximal binding values which were equal to the concentrations of the antigen or epitope. TAG-72 was detected in 25 specimens, at a concentration ranging from 8.4 to 562.9 pmol/g. CEA was detected in 32 of the 33 specimens and its concentration ranged from 8.8 to 525.3 pmol/g. The distribution of TAG-72 by IV-QAR coincided with that of the tumor cells in 41.4% of the pathologic lesions. The distribution of CEA coincided with the tumor cells in 80.5% of pathologic lesions, nearly twice the TAG-72. The concentration of TAG-72 was significantly higher in mucinous adenocarcinoma and mucin containing adenocarcinomas than other types of adenocarcinomas. There was no significant difference in the concentration of CEA among the pathologic types of stomach cancer. In summary, stomach cancer exhibited wide variations in TAG-72 and CEA expression. CEA expression was more frequent and homogeneous than TAG-72.

Adenocarcinoma↗
PubMed1995

Craniofacial injuries in unhelmeted riders of motorbikes.

We studied 1160 consecutive craniofacial injuries sustained by unhelmeted motorbike riders in Taipei, Taiwan, between 1990 and 1993, in order to investigate the distribution, type and severity of these injuries. The average age of the victims was 31 years (SD 13.2), with 84 per cent of them being between ages 16 and 45. The facial and cranial areas were defined as being separated by the line between eyebrows and ears. The incidence of facial injuries was the same as that of cranial injuries (both 68 per cent). While facial injuries occurred most often in the cheek and chin, most cranial injuries occurred in the forehead and parietal region. Although the majority of facial injuries resulted in mild brain injuries, they may also cause serious cosmetic problems, and some were associated with serious brain damage. Motorbike riders need good face protection. Since most motorbikes in Taipei travel relatively slowly, these results may also apply to bicyclists; in other words, cyclists may also need good face protection.

Accidents, Traffic↗