Biomedical subjects

S J Lin

Publications and source records attributed to S J Lin.

At least 145 records · Page 8Linked to original sources

PubMed1995

Detection of Y-chromosomal DNA with marker chromosomes in Turner's syndrome.

Patients with clinical features of Turner's syndrome may have a 45,X/46,X + mar or 46,X + mar karyotype. It is estimated that phenotypic females or intersexuals with a Y chromosome and gonadal dysgenesis have a 20% risk of developing gonadoblastoma, so it is crucial to know whether Turner's syndrome patients have a Y chromosome. We studied the chromosomal make-up of four patients with Turner's syndrome using the polymerase chain reaction (PCR). Nine Y-chromosomal loci including four loci (PABY, SRY, ZFY, DYS14) on the short arm, one loci (DYZ3) on the centromere, and four loci (DYS132, DYS1, DYZ1, DYZ2) on the long arm were amplified to determine the origin of marker chromosomes. Three patients were identified as having Y chromosome DNA. Patient 1 contained the presumed gonadoblastoma locus (DYS132) and a prophylactic gonadectomy was carried out. DNA extracted from dysgenetic gonads did not show Y chromosome DNA. A rapid, highly sensitive and isotope-free method for detection of abnormal Y chromosomes in Turner's syndrome patients has been developed. Chromosome in situ hybridization analysis is required to confirm the PCR results, to provide further evidence for molecular organization of these marker chromosomes.

Adult↗

PubMed1995

Short-term and long-term effects of benazepril in mild to moderate hypertensives.

BACKGROUND: Benazepril hydrochloride is a non-sulfhydryl-containing, angiotensin-converting enzyme (ACE) inhibitor. The short-term and long-term antihypertensive effects of benazepril remain to be established in Chinese. METHODS: Hypertensive subjects with diastolic blood pressure 95-110 mmHg, after two week placebo run-in first, entered a four-week double-blind phase with treatment of benazepril 10 mg once daily or captopril 25 mg three times daily, then received one-year open treatment of benazepril 10 mg daily with or without diuretics. Ambulatory blood pressure monitoring was performed at the end of placebo run-in, after four-week double-blind phase, and after one-year open treatment. RESULTS: Of the 75 subjects (41 male, 34 female, mean age 57 +/- 12 years, range 34-88 years) who completed the double-blind phase, 42 subjects finished the one-year extension phase. Reasons for withdrawal from the study included irritable cough (16, 21%), hypotension (1, 1%), and poor compliance (16, 21%). During the short-term double-blind phase, benazepril reduced clinic and mean 24-h ambulatory blood pressure by -21/-10 mmHg and by -17/-10 mmHg respectively, and captopril by -21/-13 mmHg and by -17/-10 mmHg respectively. After one-year open treatment by benazepril for the 42 subjects, the one-year average clinic blood pressure was 134/88 mmHg (155/104 mmHg at entry and 135/93 mmHg at the end of the double-blind phase), and the mean 24-h ambulatory blood pressure was 137/87 mmHg (149/95 mmHg at entry and 132/84 mmHg at the end of the double-blind phase). CONCLUSIONS: The antihypertensive effect of benazepril 10 mg daily with or without diuretics is not significantly different from that of captopril 75 mg daily in the short-term and can reasonably be maintained for one year.

Adult↗

PubMed1995

Prevalence of permanent primary congenital hypothyroidism in Taiwan.

The purpose of this study was to find the prevalence of permanent primary congenital hypothyroidism in Taiwan. From January 1988 to December 1990, there were 991,132 live births in Taiwan. Of these, 329,891 neonates were screened for primary congenital hypothyroidism. Fifty-seven cases of permanent primary congenital hypothyroidism were confirmed. Hence, the prevalence of permanent primary congenital hypothyroidism in that period in Taiwan was 1 in every 5,788 live births. There was a female preponderance with a female to male ratio of 1.7. Of 54 infants who had a thyroid scan, 36 were found to have an ectopic thyroid gland, while 11 were found to have dyshormonogenesis. Among the 57 infants, one case with a delayed rise in the serum thyrotropin level was missed on initial screening. When compared with other studies, these data suggest that the prevalence of permanent primary congenital hypothyroidism varies in different ethnic groups throughout the world.

Congenital Hypothyroidism↗

PubMed1995

Detection of Y-chromosome sequences in patients with X-chromosome abnormalities.

The polymerase chain reaction was used to test 18 adults and eight fetuses with numerical or structural X-chromosome abnormalities for the presence of nine Y-specific loci. Y-chromosomal DNA was detectable in one adult patient with X-chromosome mosaicism. This study and previous reports provide evidence to support further screening of patients with X-chromosome abnormalities for the presence of Y-chromosomal DNA sequences. Long-term follow-up of patients with Y-chromosomal sequences is required to determine the risk of gonadal neoplasms and other abnormal phenotypes.

Adolescent↗

PubMed1994

A Y-associated allele is shared among a few ethnic groups of Asia.

In our previous study, both of Y-associated alleles, Y1 and Y2, were detected in Japanese and Koreans, but only the Y1 allele was detected in each of other populations including Chinese in both Beijin and Guangzhou areas, Caucasians, Africans, and Jewish. In the present study, these observations were extended to other ethnic groups in East Asia. Evenks in central Siberia and Khalkhs in Mongolia had only the Y1 allele. On the other hand, two ethnic groups, Fo-lo and Hakka, in Taiwan had both of the Y1 and the Y2 alleles. Three of the eight Y2-positive men, 2 Fo-lo and a Hakka, shared family name Chen. Both Hakka people and ancestors of Chen families could be traced to the Province of Henan in northern China in early 4th century. They arrived in Fujian/Guangdong area in the south-east China via various routes and then some of them migrated to Taiwan in the 18th century. It is tempting to speculate that the Y2 allele may be originated from an ancestral population in Henan from which, Japanese, Koreans, and some of the Taiwanese diverged.

Alleles↗

PubMed1994

Trace analysis of acetaldehyde as fluorogenic derivative by high performance liquid chromatography.

A sensitive method is described for the determination of acetaldehyde as a fluorogenic derivative of decahydroacridin-1,8-dione by high performance liquid chromatography. The analytical derivatization is based on the reaction of acetaldehyde in an acidic aqueous system with 1,3-cyclohexanedione and ammonium acetate. The resulting derivative was separated by a reversed-phase C-18 column and monitored with a fluorescent detector (lambda ex, 375nm; lambda em, 512nm). Several parameters affecting the derivatization of acetaldehyde were studied. The linear range of the method for the quantitation of acetaldehyde was between 20 and 800 pmol in aqueous sample (0.5 mL). Application of the method to the analysis of acetaldehyde in plasma was performed.

Acetaldehyde↗

PubMed1993

Increased aortic endothelial death and enhanced transendothelial macromolecular transport in streptozotocin-diabetic rats.

Hypertension, cigarette smoking and diabetes mellitus are well-known risk factors for atherosclerosis and coronary heart disease. Repeated endothelial cell injury and increased lipid entry have been suggested as initiating events in atherogenesis. Our previous studies have demonstrated that the frequency of endothelial cell death and associated endothelial permeability were significantly increased in the aorta of spontaneously hypertensive rats and chronic oral nicotine-treated rats. In the present investigation, we examined the hypothesis that diabetes also increases the frequency of arterial endothelial cell death and hence transendothelial macromolecular transport, which may have some implications in increasing lipid entry and thus accelerating atherogenesis. Diabetes was induced in 15 male Sprague-Dawley rats by intraperitoneal injection of 60 mg streptozotocin per kg body weight. The duration of diabetes was 6 weeks. A group of 15 age-matched rats, injected only with the buffer and maintained over the same time period, served as the controls. In en face preparations of the thoracic aorta, IgG-containing dead endothelial cells were identified by an indirect immunoperoxidase method, and endothelial leakage to Evans blue-albumin complexes was quantified by fluorescence microscopy. Diabetic rats, compared to control rats, had significantly higher values for the frequency of endothelial cell death (0.77 +/- 0.10% vs 0.38 +/- 0.04%; p < 0.005 by two-tailed, unpaired Student's t-test) and the number density of Evans blue-albumin leaky foci (4.33 +/- 0.48/mm2 vs 2.99 +/- 0.38/mm2; p < 0.05 by two-tailed, unpaired t-test) in the aorta.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Pretibial epidermolysis bullosa: a clinicopathologic study.

BACKGROUND: Pretibial epidermolysis bullosa (PEB) is a rare variant of dystrophic epidermolysis bullosa (DEB) that predominantly involves the pretibial skin. OBJECTIVE: We report 19 cases of DEB with pretibial predilection and our findings on anchoring fibrils. METHODS: Patients with blisters and scars that primarily involved the pretibial were selected. Blisters and noninvolved skin were studied by light and electron microscopy. Anchoring fibrils were quantified by morphometry. RESULTS: There were 19 patients from 13 families. The inheritance was autosomal dominant in 10 families and sporadic in one family, and sibling involvement was present in two families. Nail dystrophy was noted in all patients. Pruritus was a common feature. Extensive prurigo occurred in four patients. Eight patients had skin lesions that exclusively affected the legs and were diagnosed as PEB. The remaining patients also showed some albopapuloid or hypertrophic scars at sites other than the leg, features seen in the albopapuloid or Cockayne-Touraine types. These were labeled as albopapuloid PEB or Cockayne-Touraine PEB. Common ancestry and various combinations of PEB, with albopapuloid or Cockayne-Touraine type of EB, were noted in some families. Compared with normal controls, the anchoring fibrils were rudimentary and sparser in both lesional and nonpredilected normal skin, although in the latter the changes were less marked in PEB than in the albopapuloid or Cockayne-Touraine types. CONCLUSION: Common ancestry may contribute to the higher incidence of DEB, especially PEB, in Tainan, Taiwan. The abnormalities of anchoring fibrils were not restricted to the predilected site in PEB and did not distinguish PEB from other types of DEB.

Adolescent↗

PubMed1993

Effect of pravastatin on fatty acid profile of low density lipoprotein in patients with hypercholesterolemia.

We gave pravastatin, an HMG-CoA reductase inhibitor, to 21 hypercholesterolemic patients for 12 weeks after they had been on dietary therapy for 12 weeks. In addition to inducing a significant reduction of total cholesterol and LDL-cholesterol, pravastatin significantly decreased the proportion of linoleic acid (18:2) and increased that of saturated (FA) (16:0 and 18:0) in the cholesterol ester of LDL. Linoleic acid was also reduced in the triglyceride of LDL. Besides, monounsaturated FA (16:1 and 18:1) were increased in the cholesterol ester, triglyceride and phospholipid of LDL, but the changes in monounsaturated FA were not statistically significant. The effect of pravastatin on the FA profile of LDL was similar to that of fibric acid derivatives. The mechanism as well as the clinical implication of these changes await further investigation.

Adult↗

PubMed1993

Inhibitory effects of curcumin on protein kinase C activity induced by 12-O-tetradecanoyl-phorbol-13-acetate in NIH 3T3 cells.

Curcumin is a dietary pigment responsible for the yellow color of curry. It is a potent inhibitor of tumor promotion induced by 12-O-tetradecanoyl-phorbol-13-acetate (TPA) in mouse skin. When mouse fibroblast cells (NIH 3T3) were treated with TPA alone, protein kinase C (PKC) translocated from the cytosolic fraction to the particulate fraction. Treatment with 15 or 20 microns curcumin for 15 min inhibited TPA-induced PKC activity in particulate fraction by 26 or 60% and did not affect the level of PKC protein. Curcumin also inhibited PKC activity in both cytosolic and particulate fractions in vitro by competing with phosphatidylserine. However, the inhibitory effect of curcumin was reduced after preincubation with the thiol compounds. These findings suggest that the suppression of PKC activity may contribute to the molecular mechanism of inhibition of TPA-induced tumor promotion by curcumin.

3T3 Cells↗

PubMed1993

X chromosome mosaicism in patients with recurrent abortion or premature ovarian failure.

X chromosome mosaicism is usually associated with abnormal sexual development and reproductive performance, such as recurrent spontaneous abortion, primary or secondary amenorrhea, infertility, and premature ovarian failure. However, there is a paucity of literature which discusses these relationships. From July 1988 to December 1992, a total of 105 couples with a history of recurrent spontaneous abortion from a genetic counseling clinic and 61 women with a history of premature ovarian failure followed up in reproductive endocrinology clinics were assembled, and chromosomal analysis of peripheral blood lymphocytes was carried out. X chromosome mosaicism was found in six individuals (2.9%) out of the 105 couples with recurrent spontaneous abortion, and in five (8.2%) out of 61 women with premature ovarian failure. The karyotypes were 45,X/46,XX/47,XXX in five cases, 45,X/46,X in four cases, and 46,XX/47,XXX in two cases. The cases of complex X chromosome mosaicism (45,X/46,XX/47,XXX) presented recurrent spontaneous abortion in four cases and premature ovarian failure in one case. The cases of mosaic Turner's syndrome (45,X/46,XX) presented premature ovarian failure in three cases and recurrent spontaneous abortion in one case. The two cases of mosaic triple-X syndrome (46,XX/47,XXX) presented with premature ovarian failure and recurrent spontaneous abortion, respectively. However, the ratio of mosaic cell lines does not correlate well with the phenotypic manifestations in our cases. Our preliminary data suggest that chromosomal analysis should be done routinely in every couple with recurrent spontaneous abortion and in women with premature ovarian failure. The reproductive performance of X chromosome mosaicism is highly variable and difficult to define.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Habitual↗

PubMed1993

Successful management of a pregnancy with maternal phenylketonuria: report of a case.

Maternal phenylketonuria (PKU) is associated with significant complications such as mental retardation, microcephaly and congenital heart defects in nonphenylketonuric offspring. Dietary control with a low phenylalanine diet during the gestation period is effective in improving perinatal outcome in these cases. We present the case of a 27-year-old woman with classical features of PKU who had previously given birth to three babies, all of whom died of congenital heart disease. A low phenylalanine diet was started one month prior to the pregnancy and satisfactory fetal outcome was achieved.

Adult↗

PubMed1992

X-linked recessive inheritance of dysgenesis of corpus callosum in a Chinese family.

This report describes a new syndrome of dysgenesis of corpus callosum with other anomalies, presenting as microcephaly, mental retardation, spasticity, and unusual facial appearance in 2 Chinese brothers and their maternal cousins. To date, there has not been any case reported in the Chinese population of this syndrome. All 4 patients in this report present with the same unusual face. Hydrocephalus and/or interhemispheric cyst were found among them. This syndrome is transmitted as an X-linked trait. The nosology is reviewed and discussed.

Agenesis of Corpus Callosum↗

PubMed1992

Long-term nicotine exposure increases aortic endothelial cell death and enhances transendothelial macromolecular transport in rats.

Repeated endothelial cell injury has been suggested as an initiating factor in atherogenesis. Dying or dead endothelial cells have been shown to make significant contributions to the local enhancement of transendothelial macromolecular transport. Since cigarette smoking is one of the major risk factors for atherosclerosis, we examined the hypothesis that smoking accelerates atherogenesis by increasing the frequency of endothelial cell death and hence transendothelial macromolecular transport. Sixteen male Sprague-Dawley rats were given nicotine at a weight-adjusted dose of 5 mg/kg body wt per day in their drinking water over a period of 6 weeks. A group of 16 age-matched male Sprague-Dawley rats not exposed to nicotine and maintained over the same time period served as the control group. In en face preparations of thoracic aorta, immunoglobulin G-containing dying or dead endothelial cells were identified by the indirect immunoperoxidase method, and endothelial leakage to Evans blue-albumin (EBA) complexes (5 minutes after intravenous injection) was visualized by fluorescence microscopy. The results showed that in nicotine-treated rats, 51% of dead endothelial cells were associated with EBA leakage, which was responsible for 57% of total EBA leaky foci. Both the frequency of endothelial cell death (0.94 +/- 0.11% versus 0.40 +/- 0.04%, p < 0.0001 by two-tailed, unpaired Student's t test) and the number density of EBA leaky foci (6.45 +/- 1.23/mm2 versus 3.30 +/- 0.49/mm2, p < 0.05 by two-tailed, unpaired t test) were significantly greater in nicotine-treated rats than in control rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

Serratia marcescens bacteremia.

Serratia marcescens bacteremia has become ubiquitous recently. S. marcescens bacteremia, either hospital- or community-acquired, can no longer be treated as insignificant. We reviewed 23 episodes of S. marcescens bacteremia in 1985. Among them, 17 patients (74%) were hospital-acquired infections, while 6 (26%) were community-acquired. Nine patients died, and the case fatality rate was 39%. Eleven patients (48%) had no clinically apparent source of infection, 5 (22%) had urinary tract infection, 3 (13%) had pneumonia, 2 (9%) had biliary tract infection, 1 (4%) had intra-abdominal infection, and 1 (4%) had skin and soft-tissue infection. Nosocomial isolates are often resistant to many antibiotics. Amikacin and the beta-lactamase-stable (third generation) cephalosporins are superior to gentamicin in the treatment of nosocomial S. marcescens bacteremia. We here emphasize that the awareness and treatment of S. marcescens bacteremia in daily clinical practice is unequivocally critical.

Adult↗

PubMed1991

Cytogenetic study of twenty-two intracranial tumors.

G-banded chromosomal analysis was performed on primary cultures of 22 intracranial tumors, including eight astrocytomas, nine meningiomas, two dermoid cysts, one acoustic neuroma, one pineal teratoma and one eosinophilic granuloma. One or more chromosomally abnormal clones were observed in 6 (75%) gliomas and 5 (56%) meningiomas. There was no chromosomal abnormality found in one of the dermoid cysts, the acoustic neuroma or the eosinophilic granuloma. A teratoma and a grade IV glioma had heterogeneous hyperdiploid karyotypes. Furthermore, astrocytomas displayed nonrandom loss of chromosomes #19, #21, #22 and Y. In meningiomas, characteristic changes involving chromosome 22 were found in 5 tumors. One meningioma had a ring chromosome in addition to chromosomal loss. With our culture and harvesting techniques, cytogenetic studies can be successfully performed on nearly all intracranial tumor explants, including those derived from small biopsy specimens. Also, in our study, specific nonrandom chromosomal anomalies were found.

Astrocytoma↗

PubMed1990

Temporal and spatial changes in macromolecular uptake in rat thoracic aorta and relation to [3H]thymidine uptake.

Leaky endothelial junctions associated with cell turnover have been suggested to be a hydrophilic pathway for the transport of macromolecules across the vascular endothelium. To demonstrate focal increases in endothelial permeability, the occurrence of localized uptake of macromolecules in the rat thoracic aorta was studied at various time periods after intravascular administration of Evans blue-albumin (EBA) complexes. With fluorescence microscopy, EBA uptake in the rat thoracic aorta was visible either as discrete spots or as larger areas in both en face and cross-sectional preparations. The average size of EBA leaky spots increased with dye circulation time, indicating that there is a continuous influx of macromolecules through the transiently leaky junctions in these foci with subsequent diffusion in the vessel wall. There was heterogeneity in EBA spot size distribution, suggesting that endothelial cells undergoing turnover in different phases of the cell cycle might exhibit different extents of junctional leakage to macromolecules. The technique of [3H]thymidine labeling autoradiography was applied to en face preparations of the rat thoracic aorta for identifying replicating endothelial cells. The correlation of EBA leakage with [3H]thymidine-labeled endothelial cells was determined. Only 26% of endothelial cells with nuclear incorporation of [3H]thymidine were shown to be associated with EBA leaky foci. This lack of correlation suggests that alterations in endothelial junctional permeability accompanying cell turnover might occur only in some limited time periods of the cell cycle, e.g., the mitotic (M) phase, rather than the whole period of [3H]thymidine labeling.

Albumins↗

PubMed1990

Reliability of a clinical kinematic assessment of the sit-to-stand movement.

We examined the reproducibility of a kinematic assessment of the sit-to-stand movement in 15 healthy subjects using a standardized protocol. We examined the within-rater and between-rater reliability of the assessment using a clinically feasible method, the video-goniometric measurement method, to analyze the task. Two variables were measured to characterize the sit-to-stand movement: 1) joint angles for four body segments (head, trunk, knee, and ankle) and 2) three events (maximal trunk flexion, lift-off, and maximal trunk extension). High reproducibility was found for all joint angles, except for the head angle. Both within-rater and between-rater goniometric measurements were highly reliable (ICC greater than .80). Identification of the events was reproducible within raters and between different raters. We conclude that this method can lead to reliable assessments of a healthy population. The reliability data established in this study can be used to help clinicians determine the impairments of patients.

Adult↗