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Biomedical subjects

H C Liu

Publications and source records attributed to H C Liu.

At least 19 recordsLinked to original sources
PubMed1992

Primary intracranial germ cell tumor. Pathologic study of 51 patients.

Fifty-one primary intracranial germ cell tumors (GCT), including germinoma, teratoma, endodermal sinus tumor, choriocarcinoma and mixed GCT, were studied. The incidence of GCT in the surgically removed intracranial neoplasms was 11.1% for pediatric patients and 0.6% for adult patients. The age/sex of the patients and the location of the tumors were analyzed. Morphologic findings of these tumors were identical to that of their gonadal counterparts. Immunohistochemical studies showed that alpha-fetoprotein (alpha-AFP), human chorionic gonadotropin (HCG), and placental alkaline phosphatase (PLAP) were helpful, whereas carcinoembryonic antigen (CEA) and cytokeratin (CKER) were of little help in determining the diagnosis. Serum tumor markers, alpha-AFP and HCG, were helpful in recognizing GCT producing them. However, they could not be used for specific diagnosis because different tumors could have similar serum levels. Histopathologic study was handicapped by the small size of most specimens (which usually could not include all of the components if the tumor was a mixed GCT), but it was the only means for specific diagnosis.

Adolescent↗
PubMed1992

Comparative study of the prognostic value of nuclear grade and silver-binding nucleolar organizer region in renal cell carcinomas.

Silver-binding nucleolar organizer region (AgNOR) and nuclear grade were histologically assessed in 112 renal cell carcinomas. Nuclear grade was better capable of stratification than AgNOR in terms of survival prediction. It also had prognostic significance when total metastatic rates were evaluated. Although higher mean AgNOR numbers were constantly associated with higher nuclear grades, two arbitrary classifications of AgNOR (less than 1.5, 1.5-3.5, greater than 3.5; less than 2, 2-3, greater than 3) failed to resolve the survival difference.

Carcinoma, Renal Cell↗
PubMed1992

Microsurgical fertilization procedures: the absence of stringent criteria for patient selection.

Subzonal sperm insertion and partial zona dissection were applied in 250 in vitro fertilization cycles in couples (n = 200) with abnormal semen analyses; 61 clinical pregnancies were established (24% per egg retrieval). Patients were selected without using minimal cutoff criteria. The study included patients with 0% normal sperm forms (strict criteria), no motile sperm (but some live cells), and sperm counts which could be assessed only after centrifugation. Patients were categorized into three subsets. Group A (n = 116 cycles) failed to fertilize in a previous cycle. Group B (n = 40) was excluded from IVF due to the severity of sperm profiles, such as a maximum of 2% normal forms. Group C (n = 94) constitutes those patients for whom a standard cycle could possibly result in failure. Monospermic fertilization rates were 18% (A), 19% (B), and 24% (C). The incidences of embryo replacement were 63% (A), 53% (B), and 69% (C). Rates of clinical pregnancy were 22% (A), 23% (B), and 28% (C). The presence of one, two, or three semen abnormalities did not correlate with the outcome of microsurgical fertilization. Twenty-two percent of patients with combined oligoasthenoteratozoospermia became pregnant. Moreover, ongoing pregnancies were established in instances with 0% normal sperm forms and no progressively motile spermatozoa. It is concluded that stringent cutoff criteria may not be necessary when both partial zona dissection and subzonal sperm insertion are performed efficiently.

Culture Techniques↗
PubMed1992

Improved pregnancy outcome with gonadotropin releasing hormone agonist (GnRH-a) stimulation is due to the improvement in oocyte quantity rather than quality.

The impact of gonadotropin releasing hormone agonist (GnRH-a) on the quality and quantity of oocytes harvested in in vitro fertilization-embryo transfer (IVF-ET) patients was studied by comparing the results for patients stimulated with gonadotropin alone and with gonadotropin plus GnRH-a. Adding GnRH-a significantly improved the viable pregnancies per transfer and reduced the spontaneous abortions, which seemed to improve oocyte quality. However, when oocyte quality was evaluated by the fertilization rate and the implantation and delivery rates per embryos transferred, there were no significant difference in the results, indicating that GnRH-a did not improve the oocyte quality. On the other hand, GnRH-a significantly increased the average number of oocytes harvested, fertilized, and transferred, and this increased number of oocytes transferred has been demonstrated to increase pregnancy and multiple-pregnancy rates. Multiple pregnancy with more embryos implanted would significantly reduce the abortion rate. Abortion rates decreased inversely to the number of embryos implanted. Our data strongly suggest that the efficacy of GnRH-a on IVF-ET patients was due more to the quantity increase than the quality of embryos transferred.

Embryo Implantation↗
PubMed1992

Debrisoquine metabolism in Chinese patients with Alzheimer's and Parkinson's diseases.

We determined the oxidative phenotype and metabolic ratio of debrisoquine in 96 Chinese patients with Alzheimer's disease (n = 12), Parkinson's disease (n = 55), and using patients with stroke and cervical spondylosis as controls (n = 29). We did not find any difference in debrisoquine metabolic phenotype among Parkinson's disease, Alzheimer's disease, and control patients as judged by chi-square analysis. In addition, the metabolic ratio of all our patients was less than 12.6. The result suggested that Chinese patients with Parkinson's disease and Alzheimer's disease metabolize debrisoquine at a velocity not different from that of their Western counterparts even though the frequency distribution of debrisoquine metabolism phenotyping in these two populations is quite different.

Aged↗
PubMed1992

Correlation of nocturnal increase in plasma oxytocin with a decrease in plasma estradiol/progesterone ratio in late pregnancy.

OBJECTIVES: Our purpose was to determine whether plasma oxytocin concentrations show a daily rhythm. STUDY DESIGN: Ten women between 37 and 39 weeks of gestation volunteered for the study. They were admitted 1 to 2 days before the experiment. Three blood samples were taken with 2-minute intervals each time, at 8 AM, 4 PM, and 12 midnight. Oxytocin, 17 beta-estradiol, progesterone, and cortisol were measured by radioimmunoassay with highly specific antibodies. Statistical analysis of variance by Friedman's test was followed by multiple range testing, and p < 0.05 was considered significant. RESULTS: Significant daily rhythm was found for plasma cortisol, progesterone, and oxytocin and for the estradiol/progesterone ratio. Oxytocin showed a nocturnal peak and a strong negative correlation with the estradiol/progesterone ratio. CONCLUSIONS: The daily rhythm in plasma oxytocin parallels the rhythm in uterine activity (shown by others), suggesting a causal relationship between the two. Both may in turn be related to the ratio of circulating estradiol and progesterone.

Circadian Rhythm↗
PubMed1992

Prolactin-containing pituitary adenomas. Their characteristics and comparative study with non-prolactin adenomas.

Immunohistochemical study of 130 pituitary adenomas shows that 31% are prolactin-containing adenomas, two-thirds of which are monohormonal adenomas, i.e. prolactin cell adenoma, and one-third are multihormonal adenomas, i.e. mixed growth hormone cell-prolactin cell adenoma and plurihormonal adenoma with prolactin. Clinical symptoms including amenorrhea and galactorrhea are not useful in distinguishing prolactin from non-prolactin adenomas. Serum prolactin concentration of 80 ng/ml is a good cut-off point to distinguish prolactin cell adenoma from non-prolactin adenoma but can not separate many of the multihormonal adenomas from non-prolactin adenomas. Calcification is not only more commonly seen but also more prominent in prolactin-containing adenomas. Spheroid amyloid is present in one prolactin cell adenoma. Immunohistochemistry is specific and reliable in identifying prolactin-containing adenomas. All prolactin cell adenomas and 2/13 multihormonal adenomas show paranuclear staining of prolactin in almost every adenoma cell. The remaining (11/13) multihormonal adenomas show less prolactin cells and diffuse cytoplasmic staining of prolactin. The prolactin staining pattern in the latter group is unique and appears to be indicative of the presence of other hormone(s).

Adenoma↗
PubMed1992

Spinal dural arteriovenous anomalies.

The clinical data, radiologic findings, and treatment in 14 cases of spinal dural arteriovenous (AV) anomaly were reviewed. All patients had typical findings of feeding artery, nidus, and draining vein on spinal angiograms. Radiologic diagnosis of spinal AV malformation was first made after myelography in 13 cases and after magnetic resonance (MR) imaging in one case. Thirteen patients underwent embolization; one patient underwent repeat embolization 14 months after the first procedure. The other patient underwent surgical ligation. All patients had clinical improvement after treatment. A high index of clinical suspicion, a complete myelographic examination or an MR image of good quality, and a properly performed complete spinal angiographic study are important for early diagnosis. Embolization may be the treatment of choice. For best results, the feeding artery next to the nidus and the draining vein close to the nidus should be occluded, and the nidus itself should be obliterated.

Adult↗
PubMed1992

Evaluation of Vero cell co-culture system for mouse embryos in various media.

Our objective was to evaluate and compare the efficacy and mechanisms of co-culturing mouse embryos with Vero cells in both Dulbecco's modified Eagle's medium/Ham's F12 (DMEM/F12) and human tubal fluid (HTF) culture medium. Two-cell CB6F1 mouse embryos were cultured either in the presence of Vero cells (group A) or in culture medium alone (group B). In DMEM/F12 significantly more morulae developed in group A than in group B on day 3 (91 versus 23%; P less than 0.01). In contrast, the mouse embryos grew rapidly in HTF and significant differences were noted only in later embryonic stages (on day 5; 86% and 50%, P less than 0.01 of group A and B respectively, hatching or hatched). Similar experiments using DF1 and ICR mouse strains also revealed enhanced embryo development in the presence of Vero cells. To determine whether the embryo-enhancing effects of Vero cells were due to the removal of toxins or to the secretion of embryotrophic factors, ICR mouse embryos were cultured in fresh media with cells (group A), without cells (group B) and in cell-free conditions using cell-conditioned media which were obtained in the presence (group C) or absence (group D) of embryos. These results demonstrated that completion of hatching was highest (52%; P less than 0.01) in group A after 6 days in culture. There were no significant differences between groups B, C and D (rates of total hatching 18, 17 and 17%, respectively). It is concluded that Vero cells improve the development of mouse embryos and this is likely to be due to removal of substances inhibitory to development.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Oxytocin and bovine parturition: a steep rise in endometrial oxytocin receptors precedes onset of labor.

Oxytocin receptors were measured in myometrium and intercaruncular endometrium of cows during pregnancy and parturition. Concentrations of estradiol-17 beta, estrone, and progesterone in peripheral blood were also measured. Receptor concentrations in the endometrium rose almost 200-fold from Day 20 to term (p < 0.0001, ANOVA), from 40 +/- 11 to 7300 +/- 1430 fmol/mg protein. Myometrial receptor concentrations increased 10-fold from 180 +/- 36 fmol/mg on Day 20 to 1850 +/- 360 fmol/mg protein at term (p < 0.0001, ANOVA). During labor, endometrial receptors (6600 +/- 1300 fmol/mg) remained at prelabor values, whereas myometrial receptor concentrations had decreased to 1190 +/- 316 fmol/mg (not significant) and declined further postpartum. Plasma concentrations of progesterone declined from 4-5 ng/ml to about 2 ng/ml between Days 250 and 282 and dropped to < 0.2 ng/ml shortly before delivery. Plasma concentrations of estrone and estradiol-17 beta were below 10-20 pg/ml until Day 230. Estrone concentrations were significantly (p < 0.05) increased by Day 250 and estradiol-17 beta by Day 270, and then both rose rapidly. During labor, plasma estrone was 1135 +/- 245 pg/ml and plasma estradiol-17 beta was 226 +/- 131 pg/ml. The molar ratio of estrone and estradiol-17 beta to progesterone rose from less than 0.01 to 4.4 during labor, and was correlated with oxytocin receptor concentrations in endometrium (r = 0.5160, p < 0.001), but not those in myometrium (r = 0.0122). The regulation of oxytocin receptors by ovarian hormones in the two tissues may therefore differ.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Single photon emission computed tomography using 99Tcm-HMPAO in Alzheimer's disease.

Brain single photon emission computed tomography (SPET) using 99mTcm-hexamethylpropyleneamine oxime (HMPAO) was performed in 37 patients satisfying the standard clinical criteria of Alzheimer's disease (AD), correlating results with patient's age of onset, duration of illness, severity of dementia, neuropsychological impairment, computed tomography (CT) and EEG findings. All patients had abnormal SPET: 23 were bilaterally symmetric, 10 were bilaterally asymmetric and four showed unilateral low regional cerebral perfusion. Low perfusion in bilateral parietal regions was the most consistent finding and was present alone or with other abnormal regions in 31 patients (84%). The only significant clinical correlation was found between asymmetric SPET changes and onset of disease before the age of 65 years. Fifty per cent of patients with presenile onset, but only 19% with senile onset had asymmetric low regional cerebral perfusion. Fifteen of the 36 patients had normal brain CT scans, and 9 of 31 patients receiving EEG examination had normal results. Although clinical evaluation is the most valuable diagnostic tool, brain SPET is a sensitive test for physiological investigation in AD.

Aged↗
PubMed1992

Cerebral infarction in young men with nephrotic syndrome.

BACKGROUND AND PURPOSE: Thrombosis is one of the main complications of nephrotic syndrome; however, cerebral infarction associated with nephrotic syndrome has been rarely reported. SUMMARY OF REPORT: We describe acute cerebral infarction in two young men with nephrotic syndrome. Both had a hypercoagulable state based on hemostatic studies. By retrospectively reviewing the medical records of the past 10 years at our hospital, we found an additional five cases of cerebral infarction with nephrotic syndrome. Two of the patients were found to have nephrotic syndrome during admission for stroke. CONCLUSIONS: Hypercoagulability may be the major contributing factor of cerebral infarction in patients with nephrotic syndrome.

Acute Disease↗
PubMed1992

The application of immunocytochemistry in diagnosis of meningeal carcinomatosis in a patient with unknown primary site.

A 55-year-old female with meningeal signs was suspected to have carcinomatosis meningitis based on cytospin cytology study of cerebrospinal fluid (CSF) with Wright stain. There was no primary site of any malignancy which could be identified as the source of metastasis. Immunochemical staining for cytokeratin and carcinoembryonic antigen on suspicious large immature cells in the CSF gave positive results and confirmed the malignant nature of her disease. Intrathecal chemotherapy with methotrexate and whole brain irradiation then eradicated the symptoms rapidly. Immunocytochemistry was considered to be a very powerful diagnostic tool in management of this patient.

Adenocarcinoma↗
PubMed1992

Tailgut cyst with carcinoid: a case report.

Tailgut cyst, an unusual presacral lesion, is lined by a variety of epithelial types including squamous, columnar, transitional and cuboidal epithelium. Disorganized fascicles of smooth muscle may be seen in the cystic wall. Tailgut cysts are usually multiloculated, and often afflict adult women. In rare cases, adenocarcinoma arises within the tailgut cyst. We present a carcinoid tumor developing from the tailgut cyst. The tumor cells grow in ribbon and festoon patterns and are positive for argyrophilic granules. Immunostains for neuron-specific enolase are also positive. Ultrastructurally, dense-core, membrane-bounded neurosecretory granules are present.

Adolescent↗
PubMed1992

[Squamous cell carcinoma of the gallbladder associated with adenocarcinoma in situ: a case report].

Squamous cell carcinoma of the gallbladder associated with adenocarcinoma in situ of the mucosal columnar epithelium is extremely rare. The case presented here is the first to be documented at the Veterans General Hospital-Taipei. In this case, dysplastic columnar epithelium was discovered alongside with squamous cell carcinoma and squamous metaplasia. Focal adenocarcinoma in situ was also identified. The significance of these associated lesions and the histogenesis of squamous metaplasia and squamous cell carcinoma in gallbladder are discussed.

Adenocarcinoma↗
PubMed1992

Interinstitutional variability of follicle-stimulating hormone and estradiol levels.

OBJECTIVE: To evaluate the variability of follicle stimulating hormone (FSH) and estradiol (E2) results from different laboratories. DESIGN: Prospective analyses of sera separated and frozen, obtained from 15 female patients in the follicular phase. All kits used for radioimmunoassay (RIA) for FSH were from the Second International Reference Preparation (IRP). Four different kits were used for FSH and three for E2. SETTING: Sera obtained from each patient were separated into five test tubes and frozen. Analysis of all samples was done on the same day in each one of five participating hospital-based RIA laboratories (North Shore, Cornell, Yale, Mount Sinai, and Norfolk). PARTICIPANTS: Fifteen consecutive patients from the assisted reproductive technology program at North Shore University Hospital participated in the study. MAIN OUTCOME MEASURES: After FSH and E2 levels were tabulated for each laboratory, mean levels were calculated. RESULTS: Using the Bonferroni adjusted pairwise multiple comparisons analysis, significant differences were found between three groups of laboratories within the FSH results and three different groups within the E2 results. CONCLUSIONS: [1] Different results may be obtained on the same sera for FSH and E2 at different laboratories; [2] for FSH, even though the same IRP is used, different results are reached; [3] for E2, even when the same kits are used, results may be significantly different. These results suggest that specific FSH and E2 levels used to predict chances for achieving a viable pregnancy through in vitro fertilization should be interpreted with caution across institutions.

Estradiol↗
PubMed1992

Cognition and 99Tcm-HMPAO SPECT in Parkinson's disease.

99Tcm-hexamethylpropyleneamine oxime (HMPAO) single photon emission computed tomography (SPECT) of brain was performed in 43 unselected patients with Parkinson's disease to evaluate whether low cerebral perfusion on SPECT correlated with cognitive impairment in the patients. All patients received neurological, Mini-Mental State Examination and a neuropsychological assessment. Eighteen (41.9%) of the 43 patients were demented. Thirty patients (69.8%) had abnormal SPECT: 17 had perfusion defects in cortical regions, eight in basal ganglia and five in both regions. Of the 22 patients with abnormal cortical perfusion, 15 (68.2%) were demented; only three (14.3%) of the 21 patients without cortical defect were demented (P < 0.01). Twelve of the 15 demented patients had low perfusion in the parietal region alone or in parietal and occipital regions. The cortical perfusion defects, present in 22 (51.2%) Parkinson's patients, are highly correlated with cognitive impairment. The pattern of SPECT abnormality in most demented patients with Parkinson's disease is similar to that seen in Alzheimer's disease, suggesting that the underlying pathophysiology for dementia in patients with Parkinson's disease may be similar to that in Alzheimer's disease.

Adult↗