Biomedical subjects

H J Yu

Publications and source records attributed to H J Yu.

At least 19 recordsLinked to original sources

PubMed2001

Importance of urodynamic study before radical hysterectomy for cervical cancer.

OBJECTIVES: The aim of this study was to characterize the urodynamic findings in patients with cervical cancer before radical hysterectomy and to correlate the results with age, parity, menopausal status, and cancer stage. METHODS: All patients with cervical cancer before radical hysterectomy who underwent urodynamic study (UDS) from January 1996 through December 1998 were enrolled. Detailed history, physical examination, and multichannel UDS data including uroflowmetry, filling and voiding cystometry, stress urethral pressure profile, and 20-min pad test were obtained for each patient. The urodynamic findings of each patient were analyzed and correlated with age, parity, menopausal status, and cancer stage. RESULTS: A total of 210 patients with cervical cancer were included in the study. The mean age was 48.9 +/- 10.5 years with a mean parity of 3.3 +/- 1.7. Forty-two percent (n = 88) of patients were menopausal, and 88% (n = 184) belonged to stage IB while 10% (n = 20) were stage IIA and 2% (n = 6) stage IIB. Urodynamic study showed that only 17% (n = 37) of the 210 patients were normal, 10% (n = 21) had voiding dysfunction, 45% (n = 94) had storing dysfunction, and 28% (n = 58) had both voiding and storing dysfunctions. In addition, 51% (n = 106) had urinary incontinence and 37% (n = 78) had genuine stress incontinence (GSI), 8% (n = 16) detrusor instability (DI), and 6% (n = 12) GSI/DI. Age, parity, and cancer stage did not show any significant differences among these four groups. CONCLUSIONS: In this series, only 17% of patients with cervical cancer had normal urodynamic findings before radical hysterectomy.

Female↗

PubMed2001

Changes in endogenous monoamines in aged rats.

1. It has been documented that ageing may alter endogenous neurotransmitters. However, these results are controversial. Thus, in the present study, cerebral cortex and plasma from male Wistar rats aged 8 weeks and 6, 12 or 24 months were used to investigate the changes in monoamines using electrochemical detection. 2. A marked decrease in L-dihydroxyphenylalanine (L-DOPA) was observed in aged rats. Like the decrease in dopamine (DA), levels of 5-hydroxytryptamine (5-HT) and 5-hydroxyindolacetic acid (5-HIAA), the major metabolite of 5-HT, in aged rats were decreased in the cerebral cortex and plasma. Plasma levels of noradrenaline and levels of adrenaline in the cerebral cortex were also decreased in aged rats. Moreover, levels of 3,4-dihydroxyphenylacetic acid (DOPAC), a metabolite of DA, in the cerebral cortex and plasma were reduced by ageing. The level of homovanillic acid (HVA) in all samples was markedly increased with ageing. 3. The ratio of DOPAC/DA and 5-HIAA/5-HT, being closely linked with the activity of monoamine oxidase, was increased in the cerebral cortex and plasma with ageing. The ratio of HVA/DOPAC, an index of the activity of catechol-O-methyltransferase, was also higher in the cerebral cortex and plasma of aged rats. 4. These data suggest that ageing may alter endogenous monoamines in both the brain and peripheral tissues.

3,4-Dihydroxyphenylacetic Acid↗

PubMed2001

A case of cutaneous bronchogenic cyst over the left scapula.

Bronchogenic cyst is noted shortly after birth or in early childhood and usually presents as a swelling or draining sinus in the presternal area. Its origin and pathogenesis can be explained as a developmental anomaly of the tracheobronchial buds from the primitive foregut. The patient was a 4-year-old boy with a child-fist-sized soft mass over his left scapula, which had been detected at birth and had been gradually growing. Grossly, it appeared to be a simple cyst with clear mucoid fluid. Histopathological study demonstrated a unilocular cyst composed of ciliated pseudostratified columnar epithelia, interspersed goblet cells, smooth muscles, and mucous glands on the cyst wall, which are features compatible with cutaneous bronchogenic cyst.

Bronchogenic Cyst↗

PubMed2001

A case of childhood generalized pustular psoriasis treated with dapsone.

Acute generalized pustular psoriasis (GPP) is a rare, sometimes fatal, exudative form of psoriasis characterized by acute febrile pustular psoriasis. Unlike the adult forms, GPP in childhood tends to undergo a more benign course. It may resolve spontaneously with only supportive treatment, but may sometimes be life threatening and resistant to therapy. We report a case of GPP in 7-year-old girl treated successfully with dapsone.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2001

Two imported cases of cutaneous larva migrans.

Cutaneous larva migrans (CLM) is a rare serpiginous cutaneous eruption caused by accidental penetration and migration in the skin with infective larvae of nematode that normally do not have the human as their host. Although CLM has a worldwide distribution, the infection is most frequent in warmer climates. More recently, they have been increasingly imported from the tropics or subtropics by travelers. We experienced two patients who had pruritic serpiginous linear eruption in their skin for a few weeks after traveling to the endemic areas (Brazil and Thailand, respectively). After the treatment with albendazole, the skin lesions resolved with post-inflammatory hyperpigmentation. We report herein two cases of cutaneous larva migrans successfully treated with albendazole.

Adult↗

PubMed2001

Effect of percent free prostate-specific antigen measurement on improving the specificity of serum prostate-specific antigen testing in Taiwanese patients.

BACKGROUND AND PURPOSE: Measurement of percent free prostate-specific antigen (fPSA) has been shown to enhance the diagnostic performance of traditional serum PSA determination. We sought to determine whether measurement of percent fPSA could improve the specificity of serum total PSA testing in the detection of prostate cancer in Taiwanese patients with intermediate serum PSA concentrations. METHODS: The medical records of 211 patients examined from March 1998 through March 2000 were analyzed retrospectively; all had a serum total PSA concentration of between 4.1 and 20.0 ng/mL and negative digital rectal examination (DRE) findings, and had undergone a prostate biopsy. Biopsy results were correlated with the serum total PSA concentration and percent fPSA, which were determined using a microparticle enzyme immunoassay. Percent fPSA was calculated as the ratio of fPSA to total PSA multiple by 100. The sensitivity and specificity were calculated and the receiver operating characteristic (ROC) curves were generated from different cutoff values of percent fPSA and total PSA. RESULTS: Thirty-four patients (16.1%) had positive biopsy results (prostate cancer). Patients with positive biopsy results had significantly lower percent fPSA values than those with negative results (11.7% vs 16.0%, p < 0.001). Patients with a lower percent fPSA (< 10%) had a higher probability of a positive biopsy result than those with a high percent fPSA (> 20%) (positive biopsy rate, 29% vs 10%, p < 0.05). Using a cutoff value of 25% fPSA or below, the sensitivity, specificity, and positive predictive value in differentiating patients with positive biopsy results from those with negative results were 97%, 13%, and 18%, respectively. Consequently, 27 unnecessary biopsies could have been avoided at the cost of missing one cancer. The area under the ROC curve was 0.68 for percent fPSA and 0.63 for total PSA (p > 0.05). CONCLUSIONS: For Taiwanese patients with a serum PSA concentration of between 4.1 and 20.0 ng/mL, the incidence of prostate cancer is relatively low; measurement of percent fPSA only weakly enhances the specificity of serum PSA testing in detecting prostate cancer.

Aged↗

PubMed2000

Two closely related cDNAs encoding actin-depolymerizing factors of petunia are mainly expressed in vegetative tissues.

Actin-depolymerizing factor (ADF) is one of the small actin-binding proteins that regulate actin dynamics in cells. We have isolated two cDNA clones, PhADF1 and PhADF2, encoding ADF from cDNA libraries constructed from petal protoplast cultures and flowers of Petunia hybrida. PhADF1 and PhADF2 encode polypeptides of 139 and 143 amino acids with a calculated molecular mass of 16.04 and 16.51kDa, respectively. Co-sedimentation assay showed that the recombinant PhADF1 protein produced in Escherichia coli binds to F-actin at pH7. 0 and preferentially depolymerizes it at pH8.0. Gene tree analysis indicates that the plant ADF family can be grouped into four classes, and PhADFs are included in class I. Southern blot analyses revealed that one or two copies of PhADF genes are present in petunia genome, and several other related isoforms also exist. Northern blot analyses indicated that PhADF1 and PhADF2 are closely related and abundantly expressed in every plant organ except pollen. In addition, they are highly accumulated in mature vegetative tissue (petal, leaf, and stem). Our results indicate that the transcription of petunia ADF genes is differentially regulated by developmental signals.

Actin Depolymerizing Factors↗

PubMed2000

Reduction in renal haemodynamics by exaggerated vesicovascular reflex in rats with acute urinary retention.

1. We examined the possibility that a vesicovascular reflex is exaggerated by acute urinary retention, and that the increase in renal vascular resistance caused by this reflex may lead to renal dysfunction. We evaluated the vesicovascular responses to normal micturition (NM, transcystometric condition) and acute urinary retention (isovolumetric condition mimicking complete bladder-outlet obstruction (CBOO) and partial urethral ligation mimicking partial bladder-outlet obstruction (PBOO)) in anaesthetized female Wistar rats. 2. Acute urinary retention due to CBOO or PBOO provoked a prolonged or increased intravesical pressure, an enhancement in both bladder pelvic afferent and bladder pelvic efferent nervous activity, and an elevation in mean arterial blood pressure. 3. Single-unit analysis showed that these vesicovascular reflexes were triggered by activation of low-threshold and high-threshold bladder mechanoreceptors, but not by renal uretropelvic mechanoreceptors. 4. Bladder contraction in CBOO and PBOO conditions and graded increases in bladder volume significantly reduced renal blood flow and cortical microvascular blood flow. The acute urinary retention-induced renal vasoconstriction was mediated by the renal nerve. Renal denervation, but not bilateral ureteral resection, abolished the renal vasoconstriction associated with the vesicovascular reflexes. 5. These findings indicate that exaggerated activation of bladder afferents exerts a positive feedback effect to increase sympathetic outflow to the kidney further, thereby contributing to significant renal vasoconstriction via a renal nerve-dependent mechanism.

Afferent Pathways↗

PubMed2000

Neural mechanisms of impaired micturition reflex in rats with acute partial bladder outlet obstruction.

To determine the contribution of neural elements to micturition, we evaluated, in intact rats, the cystometrogram, pelvic afferent nervous activity, pelvic efferent nervous activity and external urethral sphincter-electromyogram activity in the normal and acute partial bladder outlet obstruction states. In the normal state, in response to saline filling, mechanoreceptor-dependent pelvic afferent nervous activity gradually activated and finally triggered a voiding reflex, including four phases of detrusor contractions. Phase 1 was characterized by an initial rising intravesical pressure, Phase 2 was characterized by a series of high-frequency oscillations in intravesical pressure, Phase 3 contraction was characterized by a rebound intravesical pressure and Phase 4 contraction was characterized by a rapid fall in intravesical pressure. In the acute partial bladder outlet obstruction state, Phase 1 contraction rose and high-frequency oscillations fell in Phase 2. This voiding dysfunction is ascribed to the bursting extraurethral sphincter activity being converted to tonic extraurethral sphincter activity. In summary, the suppressed high-frequency oscillations in Phase 2 of the detrusor muscle contraction could be detrimental to efficient voidings in the acute partial bladder outlet obstructed rat.

Acute Disease↗

PubMed2000

A neural network for 500 word vocabulary word spotting using non-uniform units.

We introduce acoustic sub-word units to neural networks for speaker-independent continuous speech recognition. The functions of segmenting input and detecting words are implemented with networks of simple structures. The non-uniform unit which we introduce in this research can model phoneme variations caused by co-articulation spread over several phonemes and between words. These units can be segmented by the network according to stationary and transition parts of speech without iteration or without considering all possible position shifts. A word lexicon can be trained by the network, which can effectively memorize all transcription variations in the training utterances of words. The results of speaker-independent word spotting of 520 words with TIMIT data are described.

Artificial Intelligence↗

PubMed2000

Localized multiple glomus tumors of the face and oral mucosa.

We describe a 54-year-old patient with an unusual localization of localized multiple glomus tumors. She had several nodules on the left mandibular area, lower lip, and anterior part of the buccal mucosa. A biopsy taken from the left mandibular area showed cystically dilated vessels lined by endothelial cells and a few outer layers of glomus cells in the dermis to subcutis. Localized multiple glomus tumors are rare, and both their facial and oral mucocal localization are extremely rare.

Actins↗

PubMed2000

[A study of ITS sequence as a molecular marker in the phylogeny of Drosophila nasuta subgroup].

A total of 1.1 kb including whole ITS (intertranscribed spacer), part of 5.8S rDNA and 2S rDNA were sequenced. The results reveal that D. pallidifrons, Taxon I and Taxon J share the same sequence, and D. albomicans and D. s. neonasuta have the other same one. Among the sequences, there were a handful of insertions, deletions and substitutions. Insertions and deletions occur mainly between outgroup and ingroups; yet only 1 insertion and 12 deletions were detected in D. niveifrons, and 1 deletion was found in D. s. sulfurigaster. Among all the substitutions in outgroup and ingroups, totally 55 transitions and 65 transvertions were detected. The value of transition transvertion is quite different to that of mitochondrial genome. We applied parsimony and NJ methods to reconstruct the phylogenetic relationships of the 7 taxa. They show that D. niveifrons is on the basis of the trees, which suggests that it be less related to the rest; D. albomicans, D. s. neonasuta, D. pallidifrons, Taxon I and Taxon J are more related. We suggested that more related topology of D. s. sulfurigaster and D. s. neonasuta due to the specific evolution of ITS, yet not meaning their real relationships. Sequence variations and phylogeny analysis reveal that the ITS may be not an informative marker to nasuta subgroup. However, secondary structure analysis by using PCFOLD 4.0 reveals that the structure of the ITS is quite conservative; the stem-loop of ITS 3'-end may be an important structure of rDNA splicing.

Animals↗

PubMed2000

Result of 11,946 gastric cancer treatment with immunochemosurgery.

Although the therapeutic results of gastric cancer have markedly improved, it still remains the most common of cancer deaths in Korea. Annually more than 700, and all together 11,946, gastric cancer patients were surgically treated from 1970 to 1998 at Seoul National University Hospital. Stage III gastric cancer is already a systemic disease, Radical surgery alone cannot cure the patient, and about 35% recurred within 2-3 years. To improve the prognosis of advanced gastric cancer, systemic treatment such as immunotherapy and chemotherapy is required in the early postoperative period to kill the micrometastatic or remaining cancer cells after curative resection. We evaluated the survival rate and prognostic factors for 9,262 consecutive patients from 1981 to 1996. The clinicopathologic variables used for evaluating prognostic values were classified into patient, -tumor- and treatment-related factors. The prognostic significance of treatment modality was evaluated in stage III gastric cancer. The five-year survival rates were 55.9% for overall patients and 64.8% for patients who received curative resection. Radical lymph node dissection was found to produce survival gains in patients with stage II and IIIa. For postoperative adjuvant therapy, immunochemotherapy was most effective in patients with stage III. In multivariate analysis, curability of operation, depth of invasion, and ratio of involved-to-resected lymph nodes were the significant prognostic factors. Consequently, early detection and real curative resection with radical lymph node dissection, followed by immunochemotherapy (particularly in patients with stage III gastric cancer) should be recommended as a standard treatment principle for patients with gastric cancer.

Adult↗

PubMed1999

Analysis of cDNAs expressed during first cell division of petunia petal protoplast cultures using expressed sequence tags.

A large-scale sequence analysis of randomly selected cDNA clones was performed to isolate numerous genes in petunia petal protoplast cultures. We have partially sequenced 1158 randomly selected genes of the cDNA library constructed from 2-6 d cultured petal protoplasts. Three hundred and sixty-five different genes were identified, 25% of which showed significant similarity to existing sequences in the petunia, and an array of other organisms. In this report, 90 independent genes are analyzed in detail. A functional categorization of the database-matched expressed sequence tags (ESTs) showed that defense- or stress-related genes, as well as genes involved in the primary metabolic pathways and in the transcriptional or translational apparatus are abundantly represented. In particular, ESTs were identified with apparent homologies to the cyclin-dependent kinase, histone, actin-depolymerizing factor, proteasome, and ubiquitin which are expected to be related to cell division or to cell cycle control.

Cell Division↗

PubMed1999

Geographic variations in utilization rates in Veterans Affairs hospitals and clinics.

BACKGROUND: In the United States, geographic variation in hospital use is common. It is uncertain whether there are similar geographic variations in the health care system of the Department of Veterans Affairs (VA), which differs from the private sector because it predominantly serves men with annual incomes below $20,000, has a central system of administration, and uses salaried physicians. Thus, it might be less likely to have geographic variations. METHODS: We used VA data bases to obtain information on patients treated for eight diseases (chronic obstructive pulmonary disease, pneumonia, congestive heart failure, angina, diabetes, chronic renal failure, bipolar disorder, and major depression). We analyzed their use of hospital and outpatient services by assessing the risk-adjusted numbers of hospital days (the average number of days a patient spent in the hospital per 12 months of follow-up, regardless of the number of hospital stays), hospital-discharge rates, and clinic-visit rates from 1991 through 1995 for the entire system and within the 22 geographically based health care networks. RESULTS: We found substantial geographic variation in hospital use for all eight cohorts of patients and all the years studied. Variations in the numbers of hospital days per person-year among the networks were greatest among patients with chronic obstructive pulmonary disease (ranging from a factor of 2.7 to a factor of 3.1) during a given year and smallest among patients with angina (ranging from a factor of 1.5 to a factor of 2.1). Levels of hospital use were highest in the Northeast and lowest in the West. The variation in the rates of clinic visits for principal medical care among the networks ranged from a factor of approximately 1.6 to a factor of 4.0; variations in the rates were greatest among patients with chronic renal failure and smallest among patients with chronic obstructive pulmonary disease. There was no clear geographic pattern in the rates of outpatient-clinic use. CONCLUSIONS: There are significant geographic variations in the use of hospital and outpatient services in the VA health care system. Because VA physicians are unable to increase their income by changing their patterns of practice, our findings suggest that their practice styles are similar to those of other physicians in their geographic regions.

Chronic Disease↗

PubMed1999

[Genetic polymorphism in natural populations of D. virilis].

In this paper we analysed the RFLP of mtDNA in Lanzhou (LZ) population of D. virilis. By reanalysing the RFLP data of our previous work on other natural populations of D. virilis, a phylogenetic tree was produced based on the UPGMA method. It shows three main clusters: the Northern populations (LZ QD), the East China populations (NJ, SH, NB) and the Southern population (QZ). With the mtDNA's RFLP data and the results of our former work on allozyme variation in natural populations of D. virilis, we suggest that there exists a latitudinal cline of genetic variation in natural populations of D.virilis. The mechanism for the maintenance of the observed latitudinal pattern is discussed.

Animals↗

PubMed1998

Hypothalamic galanin: control by signals of fat metabolism.

The peptide, galanin (GAL), is known to stimulate eating behavior, reduce energy expenditure and affect the release of metabolic hormones. Further, the activity of this peptide in the hypothalamus is modulated, in turn, by these hormones as well as by the ingestion of nutrients. The focus of this investigation is on signals related to nutrient metabolism that may also affect GAL production and, through these neurochemical events, control the ingestion of specific nutrients. Three experiments were performed in normal-weight male, Sprague-Dawley rats. In Experiment 1, the impact of food deprivation (24 and 48 h) was examined. Experiment 2 tested the effects of the compound, 2-deoxy-D-glucose (2-DG, 200 and 400 mg/kg), which blocks glucose utilization, whereas Experiment 3 studied mercaptoacetate (MA, 200 and 600 micromol/kg), which blocks fatty acid oxidation. Eating behavior was examined in some rats, whereas hypothalamic GAL activity was measured in others using radioimmunoassay, immunohistochemistry and in situ hybridization. Both food deprivation and MA (600 micromol/kg), but not 2-DG, affected GAL in the hypothalamus, in one specific area. This is the anterior parvocellular region of the paraventricular nucleus (aPVN), which has a dense concentration of GAL-containing neurons and terminals. GAL gene expression and peptide immunoreactivity in this area is enhanced by food deprivation; in contrast, it is reduced by injection of MA. Other hypothalamic sites with dense concentrations of GAL-containing neurons or fibers are unaffected by food deprivation or MA, and the antimetabolite 2-DG has no impact on GAL in any area. Behavioral measurements indicate that these shifts in GAL activity are accompanied by specific changes in eating behavior. Food deprivation which enhances aPVN GAL produces a marked increase in fat ingestion, whereas MA which reduces aPVN GAL causes a specific reduction in fat ingestion along with a stimulation of protein intake. In contrast, 2-DG preferentially enhances ingestion of carbohydrate. These findings suggest a possible relationship between GAL activity in the aPVN and the metabolic and behavioral processes of fat metabolism and ingestion.

Animals↗

PubMed1998

Neuropeptide Y in relation to carbohydrate intake, corticosterone and dietary obesity.

Neuropeptide Y (NPY) is known to stimulate eating behavior and to be related to behavioral patterns of carbohydrate ingestion. The present report investigates this relationship further to: (1) characterize the specific NPY projection activated in different dietary paradigms; (2) understand associated changes in circulating hormones that may mediate dietary effects on NPY neurons; and (3) determine whether endogenous NPY in conditions with macronutrient diets can be linked to body fat. Male albino Sprague-Dawley rats were tested in two feeding paradigms, one in which the rats were given a choice of the macronutrients, carbohydrate, fat or protein, or the other involving a single diet varying in carbohydrate of fat content. These studies consistently demonstrated a close association between the ingestion of carbohydrate and NPY levels, specifically in the arcuate nucleus (ARC) and medial portion of the paraventricular nucleus (PVN) of the hypothalamus. In addition to revealing increased NPY activity in animals that naturally select high carbohydrate when given a choice of macronutrients, a single diet with 65% carbohydrate (10% fat), compared to a control diet with 45% carbohydrate (30% fat), significantly potentiates NPY gene expression and NPY-immunoreactivity, as determined by in situ hybridization and immunohistochemistry. A further lowering of carbohydrate to 15% has little effect on NPY. Studies of medial hypothalamic fragments in vitro also reveal enhanced NPY release from hypothalamic tissue taken from rats maintained on high-carbohydrate diet. Together with NPY, circulating corticosterone (CORT) levels are also highest in a high-carbohydrate condition and positively correlated with NPY in the ARC. An association between NPY and adiposity in these dietary conditions is indicated by significantly higher levels of NPY in the medial PVN in rats with high body fat, whether consuming a high-carbohydrate of high-fat diet. This evidence, linking NPY to carbohydrate intake and circulating CORT, suggests a role for this peptide in glucose homeostasis that is normally exhibited under conditions when carbohydrate stores are low. Disturbances in this homeostatic process, associated with hyperinsulinemia and higher levels of NPY, become evident with only a moderate rise in body fat on a high-carbohydrate as well as high-fat diet.

Adipose Tissue↗