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Y K Chen

Publications and source records attributed to Y K Chen.

At least 91 records · Page 5Linked to original sources
PubMed1993

Utility of endoscopic retrograde cholangiopancreatography in the evaluation of idiopathic abdominal pain.

We investigated the role of endoscopic retrograde cholangiopancreatography in 86 consecutive patients with idiopathic chronic or recurrent abdominal pain. There were 18 males and 68 females with a mean age of 48 yr. Forty patients (47%) had previous cholecystectomy. Patients were divided into two groups: group I (normal serum alkaline phosphatase and total bilirubin) (n = 52), and group II (elevated serum alkaline phosphatase and/or total bilirubin) (n = 34). Pancreatograms were normal in all patients, including five with pancreas divisum. Cholangiograms were abnormal in 10 of the 34 patients in group II (30%), and in only three of the 52 patients in group I (6%) (p = 0.003). Bile duct stones were present in 18% of the patients in group II, and in none of the patients in group I (p = 0.003). Of the 40 post-cholecystectomy patients, four patients had bile duct stones and five had common bile duct dilation without stones. However, no stones were found in any post-cholecystectomy patients with normal liver tests. Of the 46 patients with gallbladder in situ, two patients with abnormal liver tests had common bile duct stones and two patients had common bile duct dilation without stones. These results indicate that, among patients with idiopathic abdominal pain, cholangiography should be performed primarily in those with abnormal liver tests; however, further investigation with pancreatography is unnecessary.

Abdominal Pain↗
PubMed1993

Odynophagia caused by a pericardial diverticulum.

A 31-yr-old female presented with odynophagia and weight loss. Upper gastrointestinal endoscopy, esophageal manometry, and chest x-ray all were normal. However, computerized tomography of the chest revealed a mediastinal mass, which on mediastinoscopy proved to be a pericardial diverticulum. Surgical excision of this diverticulum resulted in complete resolution of her symptoms. This case report illustrates that mediastinal lesions should be considered as a potential cause of odynophagia when esophageal disease has been ruled out.

Adult↗
PubMed1992

The effect of feed intake and body weight on purine derivative excretion and microbial protein supply in sheep.

Urinary excretion of purine derivatives (PD) was used to estimate the microbial N (MN) supply to sheep in three experiments designed to examine the effects of DMI and BW on the efficiency of microbial N supply (EMNS) to the host animal. In Exp. 1, four sheep of about 45 kg BW were given 328, 656, 984, and 1313 g of DM/d of a hay/concentrate diet in a Latin square design. Excretion of PD per kilogram of digestible organic matter intake (DOMI) increased with intake, and EMNS increased from 12.0 to 28.3 g of MN/kg of OM digested in the rumen (DOMR). In Exp. 2, 19 sheep ranging from 22 to 73 kg BW were all offered 820 g of DM/d of the same diet as that fed in Exp. 1. Although DM digestibility was relatively constant, PD excretion varied from 4.5 to 13.5 mmol/d and EMNS from 8 to 36 g of MN/kg of DOMR, both inversely related to animal BW. In Exp. 3, five sheep of 48 to 57 kg BW were given a different diet at 702, 966, or 1,237 g of DM/d. Purine derivative excretion per kilogram of DOMI increased with the DMI:BW ratio. Calculated EMNS ranged from 23 to 35 g of MN/kg of DOMR. Pooled data from all experiments showed EMNS to be related to the DMI:BW ratio. It is suggested that the DMI:BW ratio defines the ruminal digesta passage rate and hence outflow of microbial protein. The results imply that the EMNS for a given diet is not constant, but changes with intake.

Allantoin↗
PubMed1992

Marked hyperlipidemia and pancreatitis associated with isotretinoin therapy.

Isotretinoin, a retinoid derivative, is in wide use as a treatment for severe acne and other dermatologic conditions. Its effects on serum lipids, most notably the induction of hypertriglyceridemia, have been well documented. We present a case of a young woman with a previous history of gestational hyperlipidemia who developed hypertriglyceridemia and pancreatitis after initiation of isotretinoin therapy. A history of gestational hyperlipidemia may serve as a marker to help identify patients who are at increased risk for developing severe hypertriglyceridemia while receiving isotretinoin. Her case emphasizes the need to consider the possibility of pancreatitis in patients who develop abdominal pain while receiving this drug.

Abdominal Pain↗
PubMed1991

Creatine kinase isoenzymes activity in serum and buccal pouch tissue of hamsters during DMBA-induced squamous cell carcinogenesis.

The sequential changes of creatine kinase (CK) isoenzyme activity in serum and hamster buccal pouch tissue (HBPT) of normal, premalignant, and malignant stages during 13 wk of DMBA induced hamster buccal pouch squamous cell carcinogenesis, were studied. We found that the total CK activity in both serum and HBPT of the DMBA painted groups increased during the premalignant period (3-7 wk), with the peak being at 7 wk, while declining in the malignant period (9-13 wk). No significant difference in the serum and HBPT CK-MM, CK-MB and CK-BB activity, in DMBA-induced carcinogenesis, could be established. However, the macro CK type 2 (MCK-2), a cathodically migrating atypical creatine kinase isoenzyme, initially appeared in the sera and tissues of the 3rd wk DMBA-treated group. Its activity gradually increased during the premalignant and malignant stages, paralleling the increasing number of DMBA applications. There was a correlation between the degree of differentiation, and the size and number of the induced tumors with MCK-2. No MCK-2 could be detected in any of the sera or tissues of the control, nor in the 1st wk DMBA-treated group. We propose that MCK-2 is a potential tumor marker in oral malignancy and its presence may provide valuable information for early diagnosis of a possibly premalignant transforming oral lesion.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1991

[Sensorineural hearing loss in chronic otitis media].

In individuals with chronic otitis media-(COM), mixed hearing impairments are common, but it is unclear whether the raised bone conduction thresholds are a reflection of the pathologic process affecting the middle ear resulting in conductive defect. Charts of 65 patients with unilateral chronic otitis media were reviewed. These were three groups: 1) simple COM 2) COM with granulation, 3) COM with cholesteatoma. In them, the amount of sensorineural hearing loss in the third group was 20.3 dB, which was greater than the other two groups for pure-tone average. The amount of air conduction hearing loss was 66.8 dB, also the highest. In addition, the amount of sensorineural hearing loss was greater than that of normal contralateral ears in all of three groups. These findings suggest that more severe middle ear disease may result in sensorineural hearing loss. Raised bone conduction thresholds in chronic otitis media are considerably more likely to reflect the Carhart effect, rather than disease damage to the inner ear. However, for the majority of subjects, the amount of sensorineural hearing loss was judged not to be clinically significant.

Adolescent↗
PubMed1989

An analysis of alveolar macrophage mobility kinetics at dust overloading of the lungs.

On the basis of a compartmental model, an analysis is presented to describe the alveolar clearance of insoluble particles from the rat lungs at excessive lung burdens. Expressions for the transport rate of the model are derived in terms of the alveolar macrophage mobility kinetics. It is shown that the reduction of alveolar clearance from the lungs at excessive burdens is caused by a reduction of macrophage mobility at high particle burdens and increasing number of deposited particles entering the interstitial space. On the basis of these hypotheses, and the results of other studies, calculations show that a macrophage maintains its mobility up to a certain particle burden and beyond this burden the mobility is dramatically reduced.

Animals↗
PubMed1989

Cytokeratins in hamster cheek pouch epithelium during DMBA-induced carcinogenesis.

The pattern of keratin expression in hamster cheek pouch epithelium during 15-wk of DMBA-induced carcinogenesis was studied. The sequential changes in cytokeratins of premalignant and malignant tissues and comparative investigation of normal epithelial tissues were examined during a weekly sequential DMBA-induced chemical carcinogenesis. Keratin polypeptides of normal pouch epithelium appear in a molecular weight range of 43-67 kd and 5-6 proteins can be identified. The disappearance of high molecular weight keratin (61-67 kd) was observed from the 6-wk DMBA-treated premalignant group to the 15-wk DMBA-treated malignant group. An additional keratin polypeptide was noted initially on the 11th-wk-DMBA-treated group and remained to the 15th-wk-DMBA treated group.

9,10-Dimethyl-1,2-benzanthracene↗