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Biomedical subjects

Y H Chou

Publications and source records attributed to Y H Chou.

At least 37 records · Page 2Linked to original sources
PubMed2001

Cystitis glandularis mimics bladder cancer--three case reports and literature review.

Cystitis glandularis is an uncommon proliferative disorder of the mucus-producing glands within the mucosa and submucosa of urinary bladder epithelium. We report three cases with gross hematuria on first presentation. Both sonography and computer tomography revealing bladder tumor and transurethral resection was performed in all three cases. Cystitis glandularis was confirmed by pathology. Short-term follow-up of sonography and cystoscopy showed good results.

Adult↗
PubMed2001

Adult Wilms' tumor associated with polycythemia--a case report.

Both Wilms' tumor (nephroblastoma) in adults and polycythemia in Wilms' tumor are rare. Herein we report an extremely rare case of adult Wilms' tumor associated with polycythemia. A 41-year-old female was incidentally found to have right renal mass by abdominal sonography in a routine health examination. Laboratory examination revealed polycythemia (hemoglobin 20.2 g/dL). Although physical examination was unremarkable, CT scan revealed an homogeneous mass at the middle pole of right kidney, and chest x-ray revealed no metastatic lesions. Right radical nephrectomy was performed smoothly. Grossly, the tumor of 5 x 4.5 x 4.5 cm in size was well circumscribed, and had no vascular structure or collecting system involvement. Microscopic features were consistent with adult nephroblastoma. The post-operative course was uneventful. At follow-up, the patient was well, showed no evidence of recurrence and her hemoglobin level had returned to normal (hemoglobin 14.5 g/dl). We suggest that the relationship between polycythemia and Wilms' tumor should be carefully evaluated before surgical treatment.

Adult↗
PubMed2001

Sonographic features of breast abscesses with emphasis on "hypoechoic rim" sign.

BACKGROUND: There are only limited reports on the ultrasound (US) features of breast abscess. The purpose of this paper is to review the US features of breast abscess with emphasis on "hypoechoic rim" sign which is more commonly seen in chronic abscess. METHODS: In a period of 10 years, 20,998 patients were referred for breast US examinations. Medical records identified 204 patients in whom breast abscess was diagnosed. All patients were examined using high-resolution real-time US scanners. The initial ultrasound reports and hard copy images were all carefully reviewed. The grading of the echogenicity of the abscess was classified from grade 0 to grade 5. The contours of the lesions were described as smooth, macrolobulated, microlobulated, irregular, zigzag, spiculate or indistinct. The wall thickness was measured to document the presence of "hypoechoic rim" which denoted a wall thickness greater than 2 mm. The associated findings and other acoustic phenomena related to the lesion were recorded. RESULTS: One hundred and thirty-six patients (136/204) having specific aspiration and/or biopsy/histopathological results were included in the study. All of the 136 patients showed abnormal US findings (100%). Most lesions showed grade 1 or grade 2 echogenicity (117, 86%). The contour of the abscess was usually smooth (42, 31%), macrolobulated (42, 31%), or irregular (22, 16%). A hypoechoic rim was noticed in 18 lesions (13%). Focal skin thickening was chiefly noticed in 91% of superficial abscesses (39/43) and 17% of intramammary abscesses (14/84). Diffuse skin thickening was exclusively evident in the breasts coexisting with mastitis. Hypoechoic interstitial streaks were not a common finding (7%), occurring in acute abscesses. The other findings included surrounding hypoechoic amorphous tissue (26%), posterior wall enhancement (71%), distal enhancement (60%) and lateral shadows (57%). CONCLUSIONS: US plays an important role in confirmation of the clinical diagnosis of breast abscess and aids significantly in the management of inflammatory breast diseases. Presence of the hypoechoic rim surrounding a fluid space or a central area of low-level echoes (i.e., grade 1 to grade 3) is indicative of a chronic abscess.

Abscess↗
PubMed2001

Adrenal cyst--a case report.

Adrenal cysts are rare and mostly silent clinically. Herein we report a case of adrenal cyst. A 55-year-old female was incidentally found to have a left suprarenal cystic lesion with a calcified wall by abdominal sonography during a work-up for her epigastralgia and left flank pain. Then, computed tomography (CT) revealed a left adrenal cystic mass with wall calcification, magnetic resonance imaging (MRI) showed left retroperitoneal cystic mass with fluid content, and angiography demonstrated an avascular lesion. Surgical exploration was performed via a flank incision and a calcified cystic adrenal mass was excised. The pathologic diagnosis was adrenal pseudocyst with calcified wall. We discuss the diagnosis and management of adrenal cyst and briefly review the literature.

Adrenal Gland Diseases↗
PubMed2001

Bladder wall calcification after intravesical chemotherapy with mitomycin C--a case report.

Bladder wall calcification has relatively few etiologies. We present such a case and review the literature to discuss it and the method for management. This case suffered from bladder wall calcification about 3 years after intravesical chemotherapy of mitomycin C. It was found accidentally during the transurethral resection of recurrent bladder tumor. The pathology confirmed the recurrence of transitional cell carcinoma combined with marked calcification. A repeat cystoscopy was done 3 months later. Massive calcified deposits in bladder wall especially in lesion of previous transurethral resection were still noted. Randomized biopsy showed dystrophic calcification without evidence of malignancy. We suggest that biopsy and/or resection (if possible) is a reasonable approach to eliminate the possibility of invasive bladder cancer.

Administration, Intravesical↗
PubMed2001

Hand-assisted laparoscopic radical nephrectomy of renal cell carcinoma--a case report.

A 62-year-old female patient with chronic medical history of DM and hypertension was admitted due to traffic accident. She was asymptomatic until 5 days before admission. She was referred to our medical center with an abdominal CT revealing left renal tumor. The diameter of the renal mass was 50 mm. On ultrasonographic examination, a heterogenous lesion over the left kidney was noted. Renal scanning showed a cold nodule in the left kidney. Hand-assisted laparoscopic transperitoneal radical nephrectomy was performed smoothly. The kidney was removed from the hand port in the supraumbilical skin incision with a volume of 14 x 7 x 6 cm3 and weight of 570 gm. The operation time was 5 hours, blood loss was 200 cc, and no significant change of blood pressure was noted during the surgery. The patient's postoperative course was uneventful. The pathological report of this mass was renal cell carcinoma.

Carcinoma, Renal Cell↗
PubMed2001

Auditory brainstem evoked potentials in healthy full-term and pre-term infants.

BACKGROUND: Auditory brainstem evoked potentials (ABEP) are used to evaluate the integrity of auditory pathways. Since there are difficulties in the performance and still no reference ranges for pre-term infants in Taiwan, the purpose of this study was to evaluate the characteristics of ABEP in full-term and pre-term infants. METHODS: Forty full-term and 52 pre-term infants were enrolled between January and December 1997. ABEP study was performed at 3-7 days after birth, 3, 6 and 12 months of age in the full-term group while the pre-term infants were assessed at 34-36 weeks of gestational age, at term age, and at 3, 6, 12 months of corrected age. Acoustic stimulation of mixed frequency rarefaction clicks was presented to each ear through earphones. The clicks were presented at an intensity of 70-90 dB (hearing level) and a gradual decrement of intensity to 20-40 dB to determine the threshold. Electrical activity was picked up by surface electrodes. Latency of peaks I, III, V, inter-peak latency I-III, III-V, I-V and the threshold were assessed. RESULTS: In the full-term group, the peak and inter-peak latencies decreased with age. In the pre-term group, the responses of 70 dB stimulus intensity were 53.8%, 58%, 82.8%, 88.9%, 100% in the sequence and the threshold of response decreased with age. CONCLUSION: There are maturational changes after birth in both full-term and pre-term infants. We conclude that ABEP study is a sensitive, non-invasive tool for the evaluation of auditory pathway in infants.

Evoked Potentials, Auditory, Brain Stem↗
PubMed2001

Measurement of serum vitamin E isomers in fullterm and preterm infants.

BACKGROUND: This study was conducted with the following aims: (1) to construct a methodology by high-performance liquid chromatography (HPLC) to measure vitamin E levels in our neonatal units; (2) to establish a reference range of serum vitamin E levels in fullterm neonates and their mothers; and (3) to compare these to levels in the preterm group. METHODS: During a 6-month period from September 1996 to February 1997, cord blood of 34 uneventful fullterm neonates (gestational age 38-42 weeks, birth weight 2840-3530 g) and venous blood of their healthy mothers were collected. Venous blood of 35 preterm neonates (gestational age 28-34 weeks, birth weight 940-1980 g) was collected at the same time. Serum vitamin E levels were measured by HPLC. The serum vitamin E/total lipids ratio was also examined. RESULTS: Serum levels of alpha-tocopherol in 34 fullterm neonates and their mothers were 0.212+/-0.127 and 1.160+/-0.513 mg/dl, and of gamma-tocopherol were 0.029+/-0.019 and 0.214+/-0.122 mg/dl, respectively. All fullterm neonates except 2 had serum levels less than 0.5 mg/dl. There was a positive relationship between serum E levels and total lipids. In addition, the correlation between neonatal vitamin E/total lipids ratios and maternal vitamin E/total lipids ratio was statistically significant. The serum level of alpha-tocopherol in 35 preterm infants was 0.170+/-0.090 mg/dl and that of gamma-tocopherol was 0.020+/-0.015 mg/dl; both levels were much lower than those of their fullterm counterparts. But the vitamin E/total lipids ratios did not significantly differ. CONCLUSIONS: We conclude that (1) measurement of serum vitamin E levels by the HPLC method is practical, and is useful in evaluating deficiencies in preterm infants and possibly useful in monitoring the adequacy after supplementation in future study, and (2) preterm infants had a much lower level of serum tocopherol, but no difference was seen in vitamin E/total lipids ratio.

Chromatography, High Pressure Liquid↗
PubMed2001

Comparison of hand-assisted laparoscopic nephroureterectomy with open surgery for upper urinary tract tumor.

Herein we report on our initial experience in performing nephroureterectomy by hand-assisted laparoscopic surgery, and compare the results with those performed by traditional open methods. From December 2000 to September 2001, 10 patients with upper urinary tract tumors underwent hand-assisted laparoscopic nephroureterectomy. Except for one patient who required elective conversion to open surgery due to renal vein injury, this cohort of 9 patients was compared to a group of 35 patients who had received traditional open nephroureterectomy over the last 2 years. Demographic, intraoperative and postoperative data were compared retrospectively. These two groups were similar in age, body mass index, operation time and time to postoperative oral intake. However, the hand-assisted laparoscopy group was found to have significantly less blood loss, less need for parenteral narcotic and a shorter length of time needed for postoperative hospitalization than the open group. Thus, in this report we have demonstrated hand-assisted laparoscopic nephroureterectomy to be a safe and efficacious treatment of malignant urinary collecting tumors. We believe the benefits of this minimally invasive surgery make it a viable alternative technique for management of upper urinary tract tumor.

Adult↗
PubMed2000

Non-infectious epiglottitis in children: two cases report.

Two young children who suffered from thermal injuries to the epiglottis after swallowing corrosive agent and hot water respectively. Findings, clinically and radiologically, in both children were similar to acute infectious epiglottitis. Both recovered quickly with close observation and parenteral antibiotics. Although Haemophilus influenzae type b (Hib) is the major pathogen of epiglottitis, in areas with low incidence of Hib infection and high vaccination rates, non-infectious epiglottic swelling should be considered first.

Burns↗
PubMed2000

Enhanced oxidative stress and accelerated cellular senescence in glucose-6-phosphate dehydrogenase (G6PD)-deficient human fibroblasts.

Glucose-6-phosphate dehydrogenase (G6PD) is involved in the generation of reduced nicotinamide adenine dinucleotide phosphate (NADPH) and the maintenance of the cellular redox balance. The biological effects of G6PD deficiency in nucleated cells were studied using G6PD-deficient human foreskin fibroblasts (HFF). In contrast to that of normal HFF, the doubling time of G6PD-deficient cells increased readily from population doubling level (PDL) 15 to 63. This was accompanied by a significant increase in the percentage of G(1) cells. The slow-down in growth preceded an early entry of these cells into a nondividing state reminiscent of cellular senescence. These cells exhibited a significant increase in level of senescence-associated beta-galactosidase (SA-beta-gal) staining. The importance of G6PD activity in cell growth was corroborated by the finding that ectopic expression of active G6PD in the deficient cells prevented their growth retardation and early onset of senescence. Mechanistically, the enhanced fluorescence in dichlorofluorescin (H(2)DCF)-stained G6PD-deficient cells suggests the possible involvement of reactive oxygen species in senescence. Taken together, our results show that G6PD deficiency predisposes human fibroblasts to retarded growth and accelerated cellular senescence. Moreover, G6PD-deficient HFF provides a useful model system for delineating the effects of redox alterations on cellular processes.

Cell Cycle↗
PubMed2000

The 300-kDa intermediate filament-associated protein (IFAP300) is a hamster plectin ortholog.

Plectin is a high-molecular-weight cytoskeleton-associated protein that was initially identified in intermediate filament (IF)-enriched fractions of rat C6 glioma cells. At the cellular level, plectin has been found to associate with IF networks and IF-associated structures that are involved in cell-cell and cell-substrate adhesions. IFAP300 is an IF-associated protein that was initially identified in hamster cells by a monoclonal antibody directed against a high molecular weight protein present in IF-enriched cytoskeletal preparations. Plectin and IFAP300 display similar distribution patterns within cells as determined by immunofluorescence. Based upon this and the finding that their biochemical properties are similar, it has been suggested that they may actually be orthologous proteins. In this paper we demonstrate that this is the case. Cloning and sequencing of most of the hamster plectin cDNA demonstrates that plectin is found in hamster cells and that its sequence is highly conserved between species. Using immunological cross-reactivity, epitope mapping, and immunoelectron microscopy, we show that IFAP300 is actually the hamster ortholog of plectin.

Amino Acid Sequence↗
PubMed2000

Cellular glucose-6-phosphate dehydrogenase (G6PD) status modulates the effects of nitric oxide (NO) on human foreskin fibroblasts.

Glucose-6-phosphate dehydrogenase (G6PD) plays an important role in cellular redox homeostasis, which is crucial for cell survival. In the present study, we found that G6PD status determines the response of cells exposed to nitric oxide (NO) donor. Treatment with NO donor, sodium nitroprusside (SNP), caused apoptosis in G6PD-deficient human foreskin fibroblasts (HFF1), whereas it was growth stimulatory in the normal counterpart (HFF3). Such effects were abolished by NO scavengers like hemoglobin. Ectopic expression of G6PD in HFF1 cells switched the cellular response to NO from apoptosis to growth stimulation. Experiments with 1H-¿1,2,4ŏxadiazolo¿4, 3-aquinoxalin-1-one and 8-bromo-cGMP showed that the effects of NO on HFF1 and HFF3 cells were independent of cGMP signalling pathway. Intriguingly, trolox prevented the SNP-induced apoptosis in HFF1 cells. These data demonstrate that G6PD plays a critical role in regulation of cell growth and survival.

Apoptosis↗
PubMed2000

Computer-aided diagnosis for surgical office-based breast ultrasound.

HYPOTHESIS: The computer-aided diagnostic system is an intelligent system with great potential for categorizing solid breast nodules. It can be used conveniently for surgical office-based digital ultrasonography (US) of the breast. DESIGN: Retrospective, nonrandomized study. SETTING: University teaching hospital. PATIENTS: We retrospectively reviewed 243 medical records of digital US images of the breast of pathologically proved, benign breast tumors from 161 patients (ie, 136 fibroadenomas and 25 fibrocystic nodules), and carcinomas from 82 patients (ie, 73 invasive duct carcinomas, 5 invasive lobular carcinomas, and 4 intraductal carcinomas). The digital US images were consecutively recorded from January 1, 1997, to December 31, 1998. INTERVENTION: The physician selected the region of interest on the digital US image. Then a learning vector quantization model with 24 autocorrelation texture features is used to classify the tumor as benign or malignant. In the experiment, 153 cases were arbitrarily selected to be the training set of the learning vector quantization model and 90 cases were selected to evaluate the performance. One experienced radiologist who was completely blind to these cases was asked to classify these tumors in the test set. MAIN OUTCOME MEASURE: Contribution of breast US to diagnosis. RESULTS: The performance comparison results illustrated the following: accuracy, 90%; sensitivity, 96.67%; specificity, 86.67%; positive predictive value, 78.38%; and negative predictive value, 98.11% for the computer-aided diagnostic (CAD) system and accuracy, 86.67%; sensitivity, 86.67%; specificity, 86.67%; positive predictive value, 76.47%; and negative predictive value, 92.86% for the radiologist. CONCLUSION: The proposed CAD system provides an immediate second opinion. An accurate preoperative diagnosis can be routinely established for surgical office-based digital US of the breast. The diagnostic rate was even better than the results of an experienced radiologist. The high negative predictive rate by the CAD system can avert benign biopsies. It can be easily implemented on existing commercial diagnostic digital US machines. For most available diagnostic digital US machines, all that would be required for the CAD system is only a personal computer loaded with CAD software.

Breast Neoplasms↗
PubMed2000

Effect of amphetamine on extrastriatal D2 dopamine receptor binding in the primate brain: a PET study.

[(11)C]raclopride binding to D2 dopamine receptors in the striatum is sensitive to drug-induced changes of endogenous dopamine concentration. We recently developed the new radioligand [(11)C]FLB 457, which is suitable for positron emission tomography (PET) studies of extrastriatal D2 dopamine receptors. The purpose of this PET study was to examine the effect of amphetamine on [(11)C]FLB 457 binding in extrastriatal regions. Each of three cynomolgus monkeys was examined at baseline conditions, 15 min and 3 h after I.V. injection of amphetamine (2 mg/kg). The effect of amphetamine was calculated from the ratio of specific [(11)C]FLB 457 binding to the binding in the cerebellum, a region which was used as reference for free and nonspecific binding in the brain. The changes of the ratio in the striatum, the thalamus, and the neocortex were between -1.2% and -15.5% at 15 min and -2.1% and -16.3% at 3 h, respectively, after amphetamine administration. The reductions of the binding ratios in the extrastriatal regions are similar to those reported for [(11)C]raclopride binding in the striatum. These data in a limited series of monkeys suggest that [(11)C]FLB 457 binding to D2 dopamine receptors in extrastriatal regions is sensitive to changes in the concentration of endogenous dopamine.

Amphetamine↗
PubMed2000

Hereditary haemorrhagic telangiectasia: hepatic lesions demonstrated with colour Doppler and power Doppler sonography.

Visceral vascular abnormalities in patients with hereditary haemorrhagic teleangiectasia (HHT) include teleangiectasis, arteriovenous fistula (AVF), and aneurysms. Sonographic findings and colour Doppler ultrasound (CDU) features of HHT in the liver have been described in a few reports. Presented here is the CDU finding of liver with HHT involvement in two patients, aged 52 and 29 years, respectively. Power Doppler sonography was also performed in the first patient in whom both CDU and power Doppler sonography could demonstrate the abnormal vascular channels in the liver. In the second patient, aneurysms in the left hepatic lobe and of the splenic artery were noted. Angiography was performed in both patients and confirmed the abnormal vascular lesions demonstrated by CDU and/or power Doppler sonographic findings.

Adult↗