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Biomedical subjects

C C Lin

Publications and source records attributed to C C Lin.

At least 343 records · Page 19Linked to original sources

The effects of ultrasonic stimulation on DP-bioglass bone substitute.

In previous studies, DP-bioglass showed good biocompatibility and can form a chemical bond with natural bone. After implementation in the rabbit femur condyle for 32 weeks, DP-bioglass gradually biodegraded and osteocytes grew into the material. In this study, an attempt has been made to utilize low intensity pulsed ultrasound to speed up the bone regeneration rate and DP-bioglass absorption rate when the DP-bioglass is implanted into the rabbit femur condyle as a bone substitute. The fundamental parameters of the ultrasound used were 1.5 MHz frequency, 0.5 W cm-2 intensity, on-off ratio 1:1 and 2 ms for the on-off time interval. The stimulation, in all cases, was started 24 h after the operations by applying the transducer to the skin using DIR ultrasound jelly as a coupling medium. The evaluation of the progress of bone regeneration and the material's biodegradable rate were conducted by histological examination and by measurements of the areas of regenerated bone, pores and DP-bioglass made with a planimeter. It was found that low intensity pulsed ultrasound had a profound effect on the rate both of bone regeneration and DP-bioglass bioabsorption in this rabbit model and that its mechanism of the action may be via an electromechanical kinetic effect on the cell membrane interfaces.

Animals↗

Success of endoscopic injection therapy in correlation with maximal one-day transfusion requirement.

BACKGROUND AND STUDY AIMS: The rate of blood transfusion is related to blood flow and the diameter of the bleeding vessel. Therapeutic endoscopy is less effective in larger vessels. To determine the effect of therapeutic endoscopy with pure ethanol injection in massive peptic ulcer bleeding, we conducted a retrospective study using the maximal one-day blood requirement as an indicator of the required blood transfusion. PATIENTS AND METHODS: The maximal one-day blood requirement was defined as the total amount of blood transfusion needed within a day to keep hemodynamics stable and hemoglobin above 8.0 g% before therapeutic endoscopy. From January 1986 to May 1993, 283 patients with high-risk signs of the stigmata of hemorrhage on endoscopy, who received pure ethanol injection therapy, were included in this study. There were 214 men and 69 women with a mean age of 58.4 years (ranging from 16 to 93 years). One hundred forty-three had gastric ulcers; 125 had duodenal ulcers; and 15 had stomal ulcers. Patients whose maximal one-day blood requirement was less than 1000 ml were assigned to Group I. Patients without, and patients with, major organ diseases whose maximal one-day blood requirement was more than 1000 ml were assigned to Group IIa and Group IIb, respectively. RESULTS: In Group I, 87.1% attained permanent hemostasis; 51.3% in Group IIa; and 49.4% in Group IIb. Temporary hemostasis and failure rates were 8.9% and 4.8% in Group I; 14.5% and 33.8% in Group IIa; and 21.2% and 29.4% in Group IIb. The rate of permanent hemostasis was significantly lower in patients with massive bleeding (p < 0.001) but did not differ between patients with and without major organ diseases (p > 0.05). CONCLUSION: The success rate for pure ethanol injection therapy was lower in patients with a large maximal one-day blood transfusion requirement.

Adolescent↗

Pharmacokinetics of ceftibuten in children.

The bioavailability and pharmacokinetics of ceftibuten administered as an oral suspension were characterized by several studies in young healthy male adults (19 to 39 years old) and children ranging in age from 6 months to 17 years. Ceftibuten suspension was found to be bioequivalent and thus interchangeable with a standard 400-mg capsule. As with the capsule formulation, food slightly (< 20%) affected the rate and extent of absorption of the suspension. The recommended dose of 9.0 mg/kg was found to produce comparable plasma concentrations in children of all ages (6 months to 17 years). The range of mean values of maximum plasma concentrations (Cmax) was 12 to 16 micrograms/ml at the 9.0-mg/kg dose level. Doses of 4.5, 9.0 and 13.5 mg/kg produced Cmax and area under the plasma concentration-time curve values that were dose-proportional. The half-life (t1/2) was essentially independent of age and dose, ranging from 2 to 3 hours. The apparent clearance (Cl/F), uncorrected for the fraction of drug absorbed (F), is independent of dose but appears to increase with a decrease in age. This also occurs to a lesser degree with the volume of distribution (Vd/F), uncorrected for F. Current evidence suggests that this is more likely to be caused primarily by a decrease in F than an increase in Cl. Ceftibuten rapidly and extensively reaches the middle ear fluid in children with acute otitis media. Within 4 hours concentrations in middle ear fluid are similar to plasma concentrations and can be measured for 12 hours. The ratio of area under the concentration time curve for middle ear fluid relative to plasma was about 70%.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

Glucose metabolism in 'Sphingomonas elodea': pathway engineering via construction of a glucose-6-phosphate dehydrogenase insertion mutant.

'Sphingomonas (formerly Pseudomonas) elodea' produces the industrially important polysaccharide gellan when grown in media containing glucose. Glucose catabolic enzymes and enzymes of central carbon metabolism were assayed in crude extracts of glucose-grown cultures of this bacterium. Based on these analyses it was concluded that glucose is converted to either gluconate or glucose 6-phosphate and that both of these products are converted to 6-phosphogluconate, a precursor for the Entner-Doudoroff (ED) and pentose phosphate pathways. Phosphoglucoisomerase (Pgi) activity was detected, but the lack of phosphofructokinase activity indicated that the Embden-Meyerhof glycolytic pathway is non-functional for glucose degradation. Thus, this bacterium utilizes glucose mainly via the ED and pentose phosphate pathways. Enzyme analyses suggested the involvement of glucose-6-phosphate dehydrogenase (Zwf) in glucose utilization and CO2 production. The zwf gene was cloned from 'S. elodea' and partially sequenced, and a null zwf mutant was constructed. This mutant exhibited no Zwf activity in in vitro assays, grew normally on glucose minimal medium and accumulated biomass (cells plus gellan) and produced CO2 at the same rates as the parental strain. Potential explanations for this finding are provided. Clones carrying the pgi gene were isolated fortuitously.

Amino Acid Sequence↗

Antihistamine activity, central nervous system and cardiovascular profiles of histamine H1 antagonists: comparative studies with loratadine, terfenadine and sedating antihistamines in guinea-pigs.

BACKGROUND: Sedation limits the clinical utility of classical H1 antihistamines, while newer antihistamines such as loratadine and terfenadine are non-sedating. However, clinical use of the terfenadine has been associated with rare but severe cardiac arrhythmias, in particular torsades de pointes. OBJECTIVE: To establish a quantitative experimental model for assessing the sedating and cardiotoxicity potential of non-sedating and sedating antihistamines. METHODS: Drugs were administered intravenously and the integrated amplitude of the cortical electroencephalogram (EEG) signal was recorded. The threshold dose that depressed EEG activity was compared with the dose required to inhibit by 50% the peripheral bronchospasm elicited by 10 micrograms/kg i.v., of histamine. In separate studies, the electrocardiogram (ECG) and cardiovascular effects of loratadine (30 and 100 mg/kg, i.v.), terfenadine (10 mg/kg, i.v.), promethazine (5 mg/kg, i.v.) and diphenhydramine (20 mg/kg, i.v.) were evaluated. RESULTS: The sedating antihistamines, diphenhydramine and promethazine, depressed the integrated EEG at doses between 0.6 and 2.0 times their peripheral antihistamine doses. Loratadine had no EEG depressant activity at 100 mg/kg, i.v., a dose more than 170 times its ED50 (0.58 mg/kg, i.v.) against histamine bronchospasm. We were unable to evaluate the EEG effects of terfenadine, because it produced cardiovascular collapse at 10 mg/kg, i.v. Loratadine and promethazine did not produce adverse cardiovascular effects, nor did they alter normal ECG activity. Diphenhydramine produced bradycardia followed by a transient hypertensive phase without affecting the QTc interval. In contrast, terfenadine elicited hypotension, bradycardia and significant arrhythmogenic activity, causing a prolongation of the QTc interval and a torsades de pointes--like ventricular arrhythmia. Pharmacokinetic studies after i.v. administration of loratadine (30 and 100 mg/kg) demonstrated plasma levels of loratadine and its major metabolite descarboethoxyloratadine to be several orders of magnitude greater than levels found in humans at the clinical dose of 10 mg. CONCLUSION: The CNS depressant effects of H1 antihistamines are promethazine approximately diphenhydramine >> loratadine = placebo. Of the non-sedating antihistamines, loratadine was devoid of adverse cardiovascular effects whereas terfenadine caused a pronounced disruption of the normal ECG, characterized by a torsades de pointes-like effect.

Animals↗

Ectopic supernumerary teeth as a predisposing cause in localized periodontitis. Case report.

Supernumerary teeth are relatively common in the maxillary incisor and molar areas. However, bilateral ectopic, fully erupted supernumerary mesiodentes are relatively rare. The present case documents a patient with localized periodontitis of the maxillary first and second molars associated with bilaterally erupted supernumerary teeth located in proximity to the buccal embrasure space between the molars. Combined clinical data suggested that these ectopic mesiodentes predisposed or contributed to the development of localized periodontitis.

Adult↗

Pharmacokinetics of intravenously administered isepamicin in men.

The pharmacokinetics of isepamicin, a broad-spectrum aminoglycoside antibiotic, were studied in men after intravenous administration. Three groups of six volunteers received isepamicin for 10 consecutive days by 0.5-h intravenous infusions at respective dosages of 7.5 mg/kg of body weight once daily, 7.5 mg/kg twice daily, and 15 mg/kg once daily. Levels of isepamicin in plasma and urine were determined by a specific high-performance liquid chromatography method. For all three groups, steady-state concentrations of the drug in plasma were attained with the first dose. The area under the concentration-time curve for plasma and urinary drug excretion were dose proportional. A half-life ranging from 2.0 to 2.5 h was independent of the dosage regimen. Isepamicin excreted in urine over 24 h accounted for about 100% of the dose. The results show that the pharmacokinetics of isepamicin are linear with these dosage regimens. The drug does not accumulate upon multiple dosing, undergoes no detectable biotransformation, and is cleared solely by urinary excretion.

Adult↗

Studies on Taiwan folk medicine, thang-kau-tin (II): Measurement of active oxygen scavenging activity using an ESR technique.

Using an electron spin resonance (ESR) technique, we measured the superoxide radical (O2) and hydroxyl radical (OH) scavenging activity from Mallotus repandus (Willd.) Muell.-Arg., Bauhinia championii Benth., Uncaria hirsuta Haviland and Uncaria rhynchophylla Miquel. O2- and OH were detected as spin adducts of spin traps 5,5-dimethylpyrroline-N-oxide (DMPO). The scavenging potencies of water extracts of crude drugs were evaluated in terms of their ability to reduce the peaks of spin adducts. The extract of B. championii showed the greatest superoxide radical and hydroxyl radical scavenger activity.

Ascorbic Acid↗

Anti-inflammatory and hepatoprotective effects of Solanum alatum.

Solanum alatum aqueous extract was investigated on carrageenin-induced edema and on CCl4-induced liver injury. The extract (100 or 200 mg/kg body weight) exhibited both anti-inflammatory and hepatoprotective activities. The effects were more prominent at the dose of 200 mg/kg. Histological changes such as necrosis, fatty changes, ballooning degeneration, and inflammatory infiltration of lymphocytes and Kupffer cells around the central veins were concurrently improved by treatment with the S. alatum aqueous extract.

Alanine Transaminase↗

The anti-inflammatory effects of Chinese crude drug prescriptions on experimental arthritis.

San-Miao-Warn (SMW), Tuhwo-Jih-Shen-Tang (TJS) and Dang-Quei-Nian-Tong-Tang (DGT) are Chinese traditional prescriptions. In this study, we evaluated the anti-inflammatory activities of these crude drug prescriptions in carrageenan-induced acute arthritis and complete Freund's adjuvant (CFA)-induced chronic arthritis in rats. It was found that pretreatment with SMW, TJS or DGT at a dosage of 100 mg/kg or 300 mg/kg, significantly inhibited carrageenan-induced acute arthritis. Moreover, these crude drugs also significantly suppressed the development of chronic arthritis induced by CFA. These results suggest that SMW, TJS and DGT are potential anti-inflammatory agents and may be considered as alternatives for non-steroid anti-inflammatory drugs (NSAID).

Administration, Oral↗

Studies on the agronomic characteristics, yield, and saikosaponin content of two Bupleurum species in Taiwan.

Two Bupleurum species (Bupleurums spp.), i.e., B. falcatum L. cv. Tainung No. 1 and B. kaoi Liu, Chao, et Chuang, were compared for their differences in seed germination, plant characteristics and root yield, and saikosaponin content. Experimental data showed that the most suitable temperature for seed germination of the two species was 16 degrees C. Two treatments, cold stratification at 4 degrees C for 8 weeks and presoaking by running water for 2 days, resulted in higher germination rates. Tainung No. 1 possessed a higher 1,000-seed weight than B. kaoi. However, field survival rate was higher for B. kaoi than for Tainung No.1. Results from field experiments also revealed that stem diameter, leaf width and fresh weight of various plant parts except the root were superior for Tainung No. 1 to B. kaoi. On the contrary, tiller number and root diameter and weight of B. kaoi were higher than those of Tainung No. 1. Harvest data and elevation had significant effects on the agronomic performance of the two Bupleurum spp. Measurements of most traits of the 6 month-old plants were superior to those of the 3 and 10 month-old plants. Cultivation at higher elevation (850 m) favored the development of leaf weight and root length, while cultivation at lower elevation (85 m) facilitated the development of plant height, root diameter, and root weight. Analysis of saikosaponin concentration in the root tissue revealed that average contents of 3.19 and 3.80 mg/g, respectively, for plants grown at the elevations of 850 m and 85 m. Comparison between the two species showed no significant difference in saikosaponin content, ranging from 3.45 to 3.55 mg/g.

Bupleurum↗

Protective and therapeutic effects of Curcuma xanthorrhiza on hepatotoxin-induced liver damage.

Curcuma xanthorrhiza Roxb. (Zingiberaceae family, commonly known as temu lawak or Javanese turmeric in Indonesia), which is found both wild and cultivated in Indonesia, has been traditionally used for medicinal purposes. C. xanthorrhiza is also used as a tonic in Indonesia. The aim of the present study is to clarify whether C. xanthorrhiza treatment may prevent acute liver damage induced by acetaminophen and carbon tetrachloride in mice. The results clearly indicated that extract of C. xanthorrhiza could reduce significantly the acute elevation of serum transaminases levels induced by the two kinds of hepatotoxins, and alleviated the degree of liver damage at 24 hours after the intraperitoneal administration of two hepatotoxins. It may be concluded that C. xanthorrhiza can protect the liver from various hepatotoxins, hence C. xanthorrhiza could be useful in the treatment of liver injuries and has promise as a kind of broad spectrum hepatoprotective agent.

Acetaminophen↗

Anti-inflammatory activity of Taiwan folk medicine "ham-hong-chho" in rats.

"Ham-Hong-Chho" is a folk medicine in Taiwan, derived from the entire plants of Bidens pilosa L. var. minor (Blume) Sherff (Compositae), B. pilosa L. and B. chilensis DC. The anti-inflammatory effect of aqueous extracts of the three plants against paw edema induced by carrageenan and chronic arthritis induced by complete Freund's adjuvant were determined in rats. The results indicated that paw edema induced by carrageenan was significantly decreased by treatment with aqueous extracts (150 or 300 mg/kg) of all three plants (p < 0.05) and that the effect of Bidens pilosa var. minor was the most potent. However, only extracts (500 mg/kg) of B. pilosa L. var. minor and B. pilosa L. significantly decreased the paw edema induced by complete Freund's adjuvant (p < 0.05).

Animals↗

Histological study on crude drugs pai-wei, pai-chein and indigenous species of Cynanchum in Taiwan.

The botanical origins of Cynanchum species (Cynanchum spp.) on the Taiwan market have been established by histological studies in the present paper. The results showed that the Chinese crude drug Pai-wei on the Taiwan market was derived from the dried roots of Cynanchum atratum Bunge; that of Pai-chein was derived from the dried roots of C. stauntonii (Decne.) Hand.-Mazz; and the Wanling-shu used locally in Taiwan was derived from the dried roots of C. taiwanianum Yamazaki.

Medicine, Chinese Traditional↗

A preliminary report on the correlation of vestibular Meniére's disease with electrocochleography and glycerol test.

Objective evaluation of vestibular Meniére's disease has been difficult due to the lack of audiometric findings. Thus inevitably, the existence of vestibular Meniére's disease is constantly being challenged. In recent years, electrocochleography (ECochG) has proved to be a useful tool to verify the presence of endolymphatic hydrops electrophysiologically. To further clarify the nature of this disease, we collected 40 patients prospectively who met the following conditions as diagnostic criteria for clinical vestibular Meniére's disease: i) episodic vertigo, ii) aural fullness, and iii) normal hearing. We implemented the glycerol test and extratympanic ECochG in addition to routine survey in these cases. The diagnosis was confirmed if either test result was positive. A retrospective collection of 24 cases who underwent endolymphatic sac surgery was made to evaluate in retrospect the existence of endolymphatic hydrops indirectly proved by successful surgery. Results showed a positive SP/AP ratio in 25 cases (62.5%) of which 7 had bilateral positive responses. The glycerol test was positive in 5 cases including 3 who also had positive ECochG responses. In the retrospective group, 4 cases exhibited an abnormally large SP/AP amplitude ratio at preoperative baseline conditions after general anesthesia. Twenty cases showed an SP/AP ratio within normal limits. Only 7 cases (29%) showed a decrease in the SP/AP ratio at different surgical steps. Short-term surgical results showed a 96% success rate of relief of vertiginous symptoms. Symptoms of fullness were completely controlled in 22 patients (92%). Hearing was preserved in 18 patients (75%). We conclude that i) the above-listed clinical criteria combined with these objective tests may prove to be very useful in the diagnosis of vestibular Meniére's disease, and ii) a successful control of vertigo and aural fullness after endolymphatic sac surgery indirectly indicates that endolymphatic hydrops is involved in vestibular Meniére's disease, sharing as it does, a pathophysiology that is similar to that of classic Meniére's disease.

Adult↗

A further critical assessment of the efficacy of endolymphatic sac surgery.

This paper further assesses the efficacy of two selected techniques of endolymphatic sac surgery (ELS) employing implants for the treatment of classic Meniere's disease and endolymphatic hydrops: the Arenberg inner ear valve implant and the newly developed Huang/Gibson inner ear shunt. Long-term (8-10 years) results for 57 patients given the Arenberg inner ear valve implant show that our demonstrated high success rate in achieving control of symptoms over the short term (1 year) is long-lasting and that although previously reported hearing gains have decreased in some cases, the overall long-term hearing results are better than for other surgical techniques. Preliminary results (less than 1 year) for 10 patients treated with the Huang/Gibson inner ear shunt indicate that it is comparable in efficacy to the Arenberg implant, while 4 out of the 10 patients have shown remarkable hearing gain, as detailed in case reports. These results again illustrate and substantiate the authors' previous conclusion that, in cases where there is a definitive delineation of the endolymphatic sac and its lumen, and where the sac is anatomically suitable, ELS is undoubtedly an effective modality and should be the standard primary choice for intractable Meniere's disease.

Adolescent↗

Anthropometry and lipoproteins-related characteristics of young adult males in Taiwan.

OBJECTIVES: To investigate the prevalence of obesity and the lipoprotein-related characteristics among young male adults in the Taiwan area. DESIGN AND SUBJECTS: After cluster sampling, a cross-sectional survey with a total of 936 males (mean age 20, 18-24) were enrolled. MAIN OUTCOME MEASURES: The distribution of anthropometric and lipoprotein-related variables and their correlations in young male adults were measured. The prevalence of obesity by different criterion and the lipoprotein characteristics of obese and non-obese were analyzed separately. RESULTS: The prevalence of obesity was 9.6% by the criterion of body weight greater than 20% of ideal body weight, or 12.6% by the criterion of body mass index (BMI) greater than 25. The obese subjects had significantly higher serum total cholesterol (CHOL), triglyceride (TG) and apo-lipoprotein B (apo B) and lower higher density lipoprotein-cholesterol (HDL-C) levels than the non-obese. The apo A1 levels were 141.3 and 141.9 mg/dl and the lipoprotein [a] (Lp[a]) were 17.4 and 17.1 mg/dl in obese and non-obese respectively, the difference being not statistically significant. Pearson correlation coefficients of body weight, body height, BMI, waist circumference, hip circumference and waist-hip ratio (WHR) to lipoprotein variables showed that both BMI and WHR are positively correlated with CHOL, TG and apo B, but negatively correlated with HDL-C. Furthermore the lipoprotein variables were better correlated with BMI than WHR in lean subjects (BMI < 25). However, this phenomenon was quite different in obese (BMI > 25) subjects, where the WHR was more highly correlated with lipoprotein variables than with BMI. CONCLUSION: The prevalence of obesity is slightly higher than reported in previous studies in Taiwan. The obese subjects had various abnormal lipoprotein metabolic characteristics, such as higher CHOL, TG, and apo B and lower HDL-C levels than non-obese subjects. The BMI was more highly correlated with lipoprotein variables than was WHR in lean subjects, but the WHR was more highly correlated with lipoprotein variables than was BMI in obese subjects.

Adolescent↗

Zygomycotic lung abscess: a case report.

Zygomycosis is an uncommon, but frequently fatal, fungal infection caused by members of the class Zygomycetes. The risk factors include diabetes mellitus, uremia, leukemia and use of deferoxamine as an iron-chelating agent; healthy persons also are occasionally infected. Those fungi, spread by their ubiquitous spores, most frequently involve the respiratory system. Rhinocerebral zygomycosis occurs predominantly in patients with uncontrolled diabetic ketoacidosis. Pulmonary zygomycosis most frequently is observed in granulocytopenic and corticosteroid-treated patients. Other clinical manifestations are gastrointestinal, cutaneous, disseminated and miscellaneous. This report concerns a previously robust farmer who suffered from left upper lung abscess caused by Rhizopus spp.-one member of the order Mucorales. Initially, it was intended to administer amphotericin B to a total dose of 2,000 mg; however, the patient could not tolerate such side effects as nausea, vomiting and refused further management when the cumulative dose was 948 mg. However, he did recover without further fever and cough. Chest X-ray, followed every three months, disclosed satisfactory improvement.

Amphotericin B↗