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Biomedical subjects

T J Chen

Publications and source records attributed to T J Chen.

At least 163 records · Page 9Linked to original sources
PubMed1979

Regulation and function of estrogen and progesterone receptor systems.

We have developed and validated assay methods which are appropriate for studying the subcellular distribution of estrogen receptor (Re) and progesterone receptor (Rp) in hamster uterus during the estrous cycle and pregnancy. Cytosol receptors were monitored by conventional procedures, and nuclear receptors were extracted from nuclei at 2 C using 0.5 M KCl in buffer containing glycerol and measured by ligand exchange during incubation with [3H] progesterone (P) at 2 C for 24 h or [3H] estradiol-17 beta (E2) at 30 C for 1 h. The nuclear exchange assay described herein measures total receptor and also permits estimation of unlabeled steroid in the nuclear KCl extract. Nuclear Rp translocation was shown to be target-tissue specific, hormone specific, and dependent on P dosage under in vivo conditions. The duration of nuclear Rp retention was about 6 h following exogenous P treatment. During the estrous cycle, Re and Rp levels in uterine cytosol and nuclei varied in response to the changing pattern of E2 and P secretion. Our results document a positive relationship between serum E2, nuclear Re and cytosol Rp levels during the follicular phase of the cycle. Nuclear Rp remained low on cycle days 1--3, and increased abruptly on day 4 coincident with preovulatory P secretion and cytosol Rp depletion. Nuclear Rp translocation during the preovulatory period on cycle day 4 was associated with a marked decline in nuclear Re, and the latter was demonstrated to be a rapid (2--4 h) response to P action rather than serum E2 withdrawal. The negative effect of P on nuclear Re levels may represent a fundamental mechanism for P antagonism of E action. Cytosol and nuclear Rp levels in deciduomal and myometrial tissue were responsive to experimental alteration of serum P, indicating that nuclear Rp is maintained by a continuous process of P-induced Rp translocation. Of interest was the finding in pregnant animals that Re levels declined dramatically in deciduoma as compared to myometrium. The loss of cytosol and nuclear Re from deciduomal cells cannot be attributed to changes in serum E2 or P. Thus, the intracellular regulation of Re numbers may change during differentiation of certain target cells such as those found in the deciduoma.

Animals↗
PubMedDate not supplied

Chronic lobular hepatitis: a clinicopathological and prognostic study.

A series of 80 patients with chronic lobular hepatitis (CLH) was reviewed clinically and histologically to demonstrate etiology, clinical presentation, course, and prognosis of this disorder. Data from our study indicate that CLH in Taiwan is a disease of viral origin, mostly hepatitis B (67.5%) and some non-A, non-B. It occurs predominantly in young males (81.3%); frequently commences as acute viral hepatitis (57.5%); and has clinical and laboratory features similar to convalescent viral hepatitis or even indistinguishable from full-blown acute viral hepatitis. Clinical and histological follow-up study indicate that CLH may extend for several years with remissions and relapses. No evidence of progression to cirrhosis was observed at least in a 4 1/2-year period of follow-up. It is concluded that CLH is a persistent but nonprogressive disease although the number of non-A, non-B CLH is too small to ascertain its nonprogressive course. The prognosis is generally good, and no specific therapy is required.

Adolescent↗
PubMedDate not supplied

Acute exacerbation in chronic type B hepatitis: comparison between HBeAg and antibody-positive patients.

The incidence, clinicopathological features and etiology of acute exacerbation occurring in patients with chronic type B hepatitis were assessed prospectively among 385 patients who had HBeAg and 279 who had anti-HBe in serum. During an average follow-up of 23.5 months, acute exacerbations occurred in 197 HBeAg-positive patients and in 56 anti-HBe positive patients, with a calculated annual incidence of 28.6 and 10.3%, respectively (p less than 0.001). The clinical and laboratory findings of acute exacerbations were similar in the HBeAg-positive and anti-HBe positive patients. The mean serum bilirubin and alpha-fetoprotein levels were higher in anti-HBe positive patients (p less than 0.01), but actual differences were small. The histologic features of acute exacerbations were also similar in the HBeAg-positive patients and anti-HBe positive patients. Lobular alterations were the main histologic findings; in addition, one-fourth of patients had bridging necrosis and one-fourth had piecemeal necrosis. Spontaneous reactivation of hepatitis B was the major cause of these exacerbations in both HBeAg-positive patients (91.5%) as well as anti-HBe positive patients (62.5%). Hepatitis delta virus superinfection accounted for a higher percentage of exacerbations in anti-HBe positive patients (14.3%) than in HBeAg-positive cases (6.5%). Hepatitis A and possibly non-A, non-B virus superinfections also contributed to some episodes of exacerbation. Thus, acute exacerbations of disease occurred more frequently in HBeAg-positive patients than in anti-HBe positive patients with chronic type B hepatitis, but the clinicopathological features and etiologies were similar.

Acute Disease↗
PubMedDate not supplied

The development of cirrhosis in patients with chronic type B hepatitis: a prospective study.

The incidence and contributing factors of cirrhosis developing in patients with chronic type B hepatitis were assessed prospectively in 684 clinicopathologically verified patients, of which 509 were HBeAg positive and 175 were anti-HBe positive at entry into the study. During an average follow-up period of 35.3 months, cirrhosis occurred 6 to 64 months after entry in 35 HBeAg-positive and 7 anti-HBe positive patients with a calculated annual incidence of 2.4 and 1.3%, respectively (p greater than 0.05). The incidence increased significantly with the increasing age at entry. Patients who had experienced (a) hepatic decompensation, (b) repeated episodes of severe acute exacerbation (with alpha-fetoprotein greater than 100 ng per ml and/or bridging hepatic necrosis), (c) severe acute exacerbation not accompanied by subsequent HBeAg seroconversion and (d) hepatitis B virus reactivation (particularly those with HBeAg reappearance) were found to develop cirrhosis much more frequently (p less than 0.001). Contrary to general belief, patients who had hepatitis delta virus superinfection and patients with chronic active hepatitis were not particularly prone to develop cirrhosis. We conclude that in addition to age factor, the extent, severity, duration, frequency and etiology of the hepatic lobular alterations are important factors for the development of cirrhosis in patients with chronic type B hepatitis.

Adolescent↗
PubMedDate not supplied

Clinicopathological response of HBsAg-positive chronic active hepatitis to adenine arabinoside: lack of correlation with DNA polymerase response.

Fifteen patients with HBsAg-positive, severe chronic active hepatitis, nine DNA polymerase (DNAP)-positive and six negative were treated with intravenous adenine arabinoside (Ara-A) in a dose of 10 mg/kg/day for five consecutive days during each of two consecutive weeks. Of the DNAP-positive patients, two responded with histological and clinical remission as well as permanent loss of DNAP. However, histological and clinical remission were also observed in patients with unsatisfactory DNAP response and even in DNAP-negative patients. It is suggested that, in addition to its antiviral effect, Ara-A might have another mechanism, such as immunosuppression, that induced histological and clinical remission. Alternatively, the discrepancy of response might relate to the natural course of chronic type B hepatitis. Accordingly, controlled trial is mandatory for assessing the effect of Ara-A or any other agent in the treatment of chronic type B hepatitis.

Adolescent↗
PubMedDate not supplied

Auditory effects of aircraft noise on people living near an airport.

Two groups of randomly chosen individuals who lived in two communities located different distances from the airport were studied. We monitored audiometry and brainstem auditory-evoked potentials to evaluate cochlear and retrocochlear functions in the individuals studied. The results of audiometry measurements indicated that hearing ability was reduced significantly in individuals who lived near the airport and who were exposed frequently to aircraft noise. Values of pure-tone average, high pure-tone average, and threshold at 4 kHz were all higher in individuals who lived near the airport, compared with those who lived farther away. With respect to brainstem auditory-evoked potentials, latencies between the two groups were not consistently different; however, the abnormality rate of such potentials was significantly higher in volunteers who lived near the airport, compared with less-exposed counterparts. In addition, a positive correlation was found between brainstem auditory-evoked potential latency and behavioral hearing threshold of high-frequency tone in exposed volunteers. We not only confirmed that damage to the peripheral cochlear organs occurred in individuals exposed frequently to aircraft noise, but we demonstrated involvement of the central auditory pathway.

Adult↗
PubMedDate not supplied

Determination of SCH 39304 by megabore capillary gas-liquid chromatography.

A gas-liquid chromatographic procedure for determination of SCH 39304 at low nanogram concentrations in serum, cerebrospinal fluid, and urine is presented. The methodology combines a high selectivity and sensitivity nitrogen-specific detector, a gas chromatograph equipped with a capillary "megabore" column, and an internal standard that is very similar in chemical structure to the drug being assayed. This method is suitable for both pharmacokinetic studies as well as for monitoring drug levels in patients receiving SCH 39304 for antifungal treatment.

Antifungal Agents↗
PubMedDate not supplied

Acute Q fever hepatitis in Taiwan.

We report a case of a chronic hepatitis B carrier with an episode of acute hepatitis. The patient presented with a headache, arthralgias, jaundice and fever. While the laboratory tests mimicked chronic hepatitis B with an acute exacerbation, lipogranulomatous changes seen in the liver biopsy strongly suggested the presence of Q fever. Serology testing for Coxiella burneti proved positive and the patient responded to tetracycline therapy. While previously unreported in Taiwan, Q fever is important to consider in an atypical hepatitis presentation because it is a treatable condition.

Acute Disease↗
PubMedDate not supplied

Effects of antiepileptic drugs on sperm motility of normal controls and epileptic patients with long-term therapy.

The in vitro effects of four antiepileptic drugs (AEDs) on human sperm motility were studied with a transmembrane migration method. Sperm motility of epileptic patients receiving chronic AED therapy was also investigated. Sperm motility was measured immediately after semen had been mixed with AED and after a 2-h preincubation at 37 degrees C. Both in vitro and in vivo studies demonstrated that AEDs inhibited sperm motility. When the drug effect was evaluated after the semen-AED mixture had been preincubated for 2 h, sperm motility was inhibited to 50% of control at concentrations of 1.59, 4.23, and 5.00 mM for phenytoin, carbamazepine, and valproate, respectively. Both with and without preincubation, phenobarbital, even up to 12.92 mM, did not inhibit the motility to less than 50% of the control. In the in vivo study, poor sperm motility was noted in epileptic patients with long-term AED therapy despite serum levels within the therapeutic range. Shorter duration of activity of spermatozoa was also observed in these patients. Interference with sperm membrane function by AEDs may be the underlying mechanism.

Adult↗
PubMedDate not supplied

[The need for neonatal intensive care in Taiwan: historical perspectives].

Recent vital statistics data reveals that in most of the developed countries the infant mortality has decreased reaching less than 15 per 1000 live births. The major component of this decline has been in neonatal mortality, which has been brought by neonatal intensive care. Presently a steady movement for the development of neonatal intensive care in some of the leading developing countries, including Taiwan area of Republic of China has been noticed. In these countries, however, a question has risen as to priority and justification for developing neonatal intensive care. This stems mostly from relatively high cost and additional health care manpower required for the neonatal intensive care. This communication reviews the evolution of neonatal intensive care in the Western World and with this historic perspective, attempts to access the need of neonatal intensive care in Taiwan area. The results also could be used as a basis for future research and public health policy.

Humans↗
PubMedDate not supplied

The D2 dopamine receptor gene as a predictor of compulsive disease: Bayes' theorem.

The dopaminergic system, and in particular the dopamine D2 receptor, has been profoundly implicated in reward mechanisms in the meso-limbic circuitry of the brain. Dysfunction of the D2 dopamine receptors leads to aberrant substance (alcohol, drug, tobacco and food) seeking behavior. Decades of research indicate that genetics play an important role in vulnerability to severe substance seeking behavior. We propose that variants of the D2 dopamine receptor gene are important common genetic determinants in predicting compulsive disease.

Alleles↗
PubMedDate not supplied

Factors influencing survival after hepatectomy for peripheral cholangiocarcinoma.

BACKGROUND/AIMS: Radical resection for patients with peripheral cholangiocarcinoma is rare. Prognostic factors related to survival with peripheral cholangiocarcinoma after hepatectomy have not yet been reported. MATERIALS AND METHODS: Of 41 hepatectomized patients with peripheral cholangiocarcinoma, a computer analysis of 14 clinicopathological factors on patients survival was performed with univariate and multivariate analysis. RESULTS: Median and mean survival times for patients with peripheral cholangiocarcinoma after hepatectomy were 12.0 and 22.8 months. The 1-, 2-, 3-, 4- and 5-year survival rates were 53.7%, 39.0%, 36.6%, 26.8%, and 26.8% respectively. Univariate analysis of overall survival involving all patients identified 7 factors that were associated with a significantly outcome: mucobilia (p = 0.043), capsular invasion (p = 0.007), tumor spreading type (p = 0.0003), section margin (p = 0.001), histologic type (p = 0.008), macroscopic and microscopic vascular involvement (p = 0.031), and lymphatic invasion (p = 0.004). With multivariate analysis using the COX stepwise proportional hazards model, only mucobilia, tumor spreading type and section margin were significantly related to prognosis. CONCLUSIONS: Intrahepatic bile duct carcinoma patients with mucobilia, intraductal papillomatosis and a tumor-free margin after hepatectomy had a better prognosis.

Bile Duct Neoplasms↗
PubMedDate not supplied

Vital statistics of premature and low birthweight infants in Tainan area.

UNLABELLED: Birth weight and gestational age are strongly associated with perinatal mortality and morbidity. This study was conducted to survey the vital statistics of premature and low birthweight infants in the Tainan area. Between July 1991 and April 1992, fifteen medical institutions were included on a voluntary basis: eight from level I (obstetric specialty clinic), six from level II (regional hospital), and one from level III (tertiary care center). A total of 14,307 deliveries were enrolled, accounting for about 60% of the total delivery for that year in the area. The proportions of delivery among level I, II and III were 52%, 41% and 7%, respectively. The incidence of premature singleton live birth was 4.6%, and the percentages of gestation between 20-27 weeks, 28-31 weeks and 32-37 weeks were 0.2%, 0.6% and 3.8%, respectively. The premature births accounted for 3.5%, 4.8% and 11.3% of live births at the level I, II and III hospitals, respectively. The incidence of low birthweight and very low birthweight singleton live births was 4.4% and 0.5%, respectively. The low birthweight births accounted for 3.5%, 4.5% and 11.1% of live births at the level I, II and III hospitals, respectively. The data revealed that the higher the level of hospital, the higher incidences of premature and low birthweight infant. Teenage mothers (< 20 year of age) had higher low birthweight rate. The risk of having low birthweight infants decreased progressively in mothers of age < 20 (6.3%), 20-24 (5.4%), 25-29 (4.1%) and 30-34 (3.8%), whereas it became higher in mothers older than 35 (4.8%). CONCLUSION: The incidence of premature and low birthweight births in the Tainan area was low. Teenager or those with maternal age older than 35 year were high risk groups for producing these infants.

Adolescent↗