Biomedical subjects

B Kuo

Publications and source records attributed to B Kuo.

14 recordsLinked to original sources

PubMed2002

Effects of 5-HT(3) antagonism on postprandial gastric volume and symptoms in humans.

BACKGROUND: Alosetron reduces symptoms of dyspepsia, but the physiological basis for the symptomatic benefit is unclear. AIM: To assess 5-HT3 antagonism on postprandial gastric volume and symptoms after ingestion of maximum tolerable volume of a liquid meal. METHODS: In 36 healthy volunteers, we assessed effects of placebo, 0.5 and 1 mg b.d. alosetron on fasting and postprandial gastric volumes (using single photon emission computed tomography) and symptoms based on 100 mm VAS, 30 min after maximum volume ingested. RESULTS: The 5-HT3 antagonist reduced postprandial symptoms (aggregate score: P < 0.05), nausea (P < 0.001), and tended to reduce bloating (P=0.08). Both 0.5 and 1 mg alosetron reduced nausea (P < 0.025); 1 mg alosetron reduced aggregate symptoms (P < 0.05) and bloating (P < 0.05). Effects on pain (P=0.19) and fullness (P=0.14) were not statistically significant. There were no significant effects of the 5-HT3 antagonist on volume of meal tolerated or on SPECT-measured fasting or postprandial gastric volumes. CONCLUSION: 5-HT3 antagonism reduces aggregate symptoms, nausea and bloating after a liquid meal without increase in gastric volumes, suggesting a role for 5-HT3 in afferent functions in healthy humans during the postprandial period.

Adult↗

PubMed2001

Development of an orthodontic simulator for measurement of orthodontic forces.

In this research we developed an orthodontic simulator for analysis of orthodontic forces distribution in the case of the continuous arch technique. In order to take into account vertical force, besides horizontal force and occlusogingival moment on instrumented artificial tooth, tooth root was designed as a ring load cell. Fixing each artificial tooth onto combined mechanical stages enabled variation of tooth anteroposterior position and inclination related to occlusal plane. Calibration of forces and moment of each instrumented artificial tooth showed linearity of outputs and provided the generalized inverse matrix for evaluation of forces and moments from measured strain data. A simulation to retract the anterior teeth was accomplished, and distribution of forces and moment acting at the bracket of each tooth were determined. The average accuracy was 82% and 97% in the horizontal and vertical direction, respectively, by comparing the applied forces and the evaluated ones.

Algorithms↗

PubMed2000

Genetic strategies to enhance penicillin acylase production in Escherichia coli.

We demonstrated the improvement of penicillin acylase (PAC) production by optimization of the host/vector system using genetic engineering strategies. Several expression plasmids with improved efficiency for the transcription of the pac gene and/or translation of the pac mRNA were constructed. Mutant strains, isolated by a novel screening method, were effective for use as the expression host to produce PAC. The feasibility of using the mutant strains harboring a selection of expression plasmids for the production of PAC was evaluated. The effect of the mutation(s) resulting in the improved PAC producing ability was characterized. While the production of PAC was significantly enhanced using the optimized host/vector system, the formation of PAC inclusion bodies was shown to be another step limiting the production of recombinant PAC.

Journal Article↗

PubMed1999

Clinical analysis of Mycobacterium tuberculosis infection in patients with acquired immunodeficiency syndrome.

From January 1990 to July 1998, twelve patients (10%) among 120 patients with human immunodeficiency virus infection who were hospitalized in the Veterans General Hospital-Taipei, were proved to have Mycobacterium tuberculosis infection. The mean age of these patients was 38 years, range: 25-62 years. All patients studied were in the advanced stage of acquired immunodeficiency syndrome (AIDS) with a mean circulatory CD4 lymphocyte count of 21/microL (range: 0-64/microL) and a much higher HIV viral load at initial diagnosis of M. tuberculosis infection. Because of no significant difference in the HIV viral load between patients with active pulmonary tuberculosis and those with extrapulmonary tuberculosis in this study, dissemination of M. tuberculosis did not correlate directly with a high HIV viral load, but was possibly related to the virulence of the organism itself. Chest radiographic findings at initial diagnosis of pulmonary tuberculosis were variable and atypical. Most patients (62.5%) presented with a primary pattern (lower lobe or diffuse infiltrates), while hilar lymphadenopathy was noted in more than half of the patients and cavitation was less common (only one patient). Ten patients (83.3%) had extrapulmonary involvement; the most common site being the lymph nodes. Most patients with classic drug-sensitive tuberculosis responded well to conventional standard regimens of anti-tuberculosis therapy. Since tuberculosis is transmittable, treatable, and possibly preventable, moreover the clinical presentation of tuberculosis in the patients with AIDS may be atypical and unusual, clinical physicians must keep an alert dealing with these patients for early identification and early treatment.

Acquired Immunodeficiency Syndrome↗

PubMed1998

Nocturnal gastric acidity and acid breakthrough on different regimens of omeprazole 40 mg daily.

BACKGROUND: On chronic intake of omeprazole, most healthy volunteers and patients still have nocturnal acid breakthrough (NAB), defined as night-time periods with gastric pH < 4.0 lasting for longer than 1 h. Gastro-oesophageal reflux during NAB may be particularly injurious to the oesophageal mucosa, contributing to the chronic lesions complicating the condition. AIM: To compare the effect of three different dosing regimens of omeprazole 40 mg daily with regard to suppressing nocturnal gastric acidity and avoiding NAB. METHODS: Eighteen healthy volunteers were given three different regimens of omeprazole for 7 days each in randomized order: 40 mg before breakfast (qAM), 40 mg before dinner (qPM) and 20 mg before breakfast and dinner (b.d.). On day 7, 24-h intragastric and intraoesophageal pH-metry was performed. Tracings were analysed for the period from 22.00 h until 06.00 h with regard to the percentage of time at which gastric pH was below 4.0, 3.0 and 2.0, and also the occurrence and duration of NAB. RESULTS: Nocturnal acid breakthrough was significantly more common on qAM than on qPM and b.d. (P < 0.05) dosing. The percentage of time gastric pH was less than 4.0 overnight was significantly lower on qPM (median 31.3) and b.d. (median 20.5) than on qAM (median 66.3) dosing (P=0.01 and P < 0.02, respectively). A pH threshold of 3 and 4 showed the same differences, as did median 24-h gastric pH. Daytime acidity was not significantly different. CONCLUSIONS: In healthy volunteers, dinner time or split dosing of omeprazole 40 mg daily is significantly more effective than dosing before breakfast in preventing NAB and controlling gastric acidity. These regimens should be preferred in patients in whom suppression of nocturnal gastric acidity is desirable.

Adult↗

PubMed1998

The Influence of Maternal Weight Correction Formulas in Asian Down Syndrome Screening Using alpha-Fetoprotein and Free beta-Human Chorionic Gonadotropin

> Objective: To investigate the relationship between maternal weight and serum alpha-fetoprotein (AFP) and free beta-human chorionic gonadotropin (beta-hCG) levels and to determine the methodology of correction formulas for influencing the results of Down syndrome screening in an Asian population. Methods: 8,194 normal singleton pregnancies without any congenital anomalies were screened using AFP and free beta-hCG between 14 and 22 weeks of gestation. Down syndrome risk was calculated by bivariate gaussian algorithm that combined information from the two biochemical measurements and maternal age. The all points regression method and median regression method were used to approach the study cases. Linear and quadratic regression correction formulas for AFP and free beta-hCG, either in analyte multiples of the median (MoM) or log analyte MoM, against maternal weight have been proposed in this study. Results: The mean maternal weight is 54.95 +/- 7.36 kg in Taiwanese pregnant women during the second trimester. There is a distinctly inverse relationship between maternal weight and serum marker levels. The log quadratic regression correction formula was the most satisfactory equation fit to the distribution of both AFP and free beta-hCG levels with a wide weight range. Routine weight correction may have the small benefit of reducing the screen-positive rate 0.36% at the risk cut-off level of 1:270. Conclusions: Maternal weight may affect the AFP and free beta-hCG levels. Although there is no discernible effect in maternal weight adjustment, it is worth making weight corrections for serum marker levels in order to reduce individual variance.

Journal Article↗

PubMed1996

Optimal dosing of omeprazole 40 mg daily: effects on gastric and esophageal pH and serum gastrin in healthy controls.

BACKGROUND: Little is known about the best regimen of omeprazole 40 mg/day for suppressing gastric acid and distal esophageal acid exposure. In addition, the relationship between the level of serum gastrin and gastric pH and this therapy is still uncertain. METHODS: Nineteen healthy male volunteers (mean age 25 yr) had a baseline fasting serum gastrin and 24-h ambulatory combined distal esophageal and gastric pH monitoring. Subjects underwent a 7-day course of each of three specific regimens of omeprazole 40 mg (20 mg b.i.d., 40 mg qAM, 40 mg qPM) with repeat pH and gastrin on day 6. Meals and activity patterns were constant for each subject during the test series. Medications were taken before meals. RESULTS: All dosing regimens caused significant (p < 0.01) acid reduction compared with baseline in both the stomach and the distal esophagus. There was no significant difference in the amount of acid exposure (time pH < 4) among the three dosing regimens in the esophagus and between qAM and qAM dosing in the stomach. However, b.i.d. dosing gave better (p < 0.05) gastric acid suppression compared with single daily dosing in 15 of 19 subjects. When the baseline was compared with all regimens of omeprazole 40 mg, there was a significant difference with both the serum gastrin (p < 0.01) and the percentage time gastric pH was < 4 (p < 0.01). The correlation between change in serum gastrin and change in percentage time gastric pH was < 4 was poor (r = 0.26). CONCLUSIONS: Divided dosing of omeprazole 20 mg b.i.d. provides superior gastric acid suppression to either once a day regimen of omeprazole 40 mg in most individuals. Serum gastrin levels do not correspond well to gastric pH, necessitating the use of gastric pH monitoring to accurately determine the response to gastric acid suppression.

Adult↗

PubMed1995

The effect of nasogastric intubation on gastroesophageal reflux: a comparison of different tube sizes.

OBJECTIVE: Previous reports have revealed conflicting conclusions about whether tubes placed across the esophagogastric junction (EGJ) have promoted reflux and whether there is potential for subsequent esophageal mucosal damage. The purpose of this study was to examine whether commonly used tubes (diameters: 2.1 mm, antimony pH probe and 3.8 mm, nasogastric tube) promote reflux under typical inpatient conditions. METHODS: Eight asymptomatic volunteers (five male, mean age 27.6 yr) underwent three sessions, each lasting 6 hours postprandially, while supine with the head elevated 20 degrees. In randomized order, the subjects had either a 2.1-mm tube, 3.8-mm tube, and 2.1-mm tube together or no tube across the EGJ. The subjects were fed 500 ml of Ensure Plus at the beginning of the study. Reflux was measured by a pH probe placed 5 cm above the lower esophageal sphincter. The number of reflux episodes, number of reflux episodes more than 5 minutes, longest reflux episode, time esophageal pH was less than 4, and percentage total time pH was less than 4 were evaluated. RESULTS: Over the 6 hours, no abnormal reflux was shown with either tube size across the EGJ. CONCLUSIONS: Over a 6-h period, a tube (pH probe alone or combined with nasogastric tube) across the EGJ does not promote an increase in the amount of postprandial supine gastroesophageal reflux in normal volunteers.

Adult↗

PubMed1985

Hair zinc, scalp hair quantity, and diaper rash in normal infants.

Hair zinc concentration was determined by atomic absorption spectrophotometry in 308 normal newborn infants and 199 normal infants aged one to twelve months. Hair zinc concentration declined from 204 micrograms/gm at birth to 112 micrograms/gm at age eight months, and then rose to 144 micrograms/gm at age twelve months. Diaper rash was significantly associated with reduced hair zinc, and infants with the least hair had lower zinc levels than infants with the most hair. The data indicate that hair loss and diaper rash found in normal infants is significantly associated with a reduction in hair zinc concentration.

Diaper Rash↗

PubMed1983