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Biomedical subjects

J H Lin

Publications and source records attributed to J H Lin.

At least 289 records · Page 16Linked to original sources
PubMed1989

Measurement of boar sperm motility by the trans-membrane migration method.

The conventional microscopic methods for evaluating sperm motility of domestic animals are mostly inadequate due to their subjectivity and lack of precision. Recently, a trans-membrane migration method, originally developed for the examination of human sperm motility, has substantially overcome these problems. This study investigated the applicability of the method to boar sperm motility measurement. The apparatus used was simple and consisted only of syringe plungers, poriferous membranes, and modified multi-well culture plates. It measured the proportion of sperm in the semen that moved across the membrane after incubation at 37 degrees C for 3 hr. The sperm motility as measured by this method correlated well with that measured by direct microscopic examinations. The measurement was more reliable using an 8-microns instead of a 5-microns pore-size membrane. The method was found to work equally well for the sperm motility measurement of the semen with a sperm concentration between 1.5 x 10(8)/ml and 6.0 x 10(8)/ml. The results indicate that this method is a simple, objective, quantitative, and reproducible design for the measurement of boar sperm motility.

Animals↗
PubMed1988

Expression of heme oxygenase gene in rat and human liver.

Developmental changes of microsomal heme oxygenase were studied. In human fetal liver, the enzyme activity was 8 times higher than that detected in the adult liver. On the other hand, adult livers contained 4 times more cytochrome P450 than fetal livers. Elevated heme oxygenase activity in fetal liver was not due to modulators present in the microsomes. Similar to human, rat fetal liver also contained high enzyme activity which appeared to be regulated at the transcriptional level. Hybridization analysis of rat liver RNAs with cDNA for rat heme oxygenase revealed that the level of mRNA for the enzyme was 3-fold higher in the fetus than in the adult. The low cytochrome P450 content may be due in part to the high heme oxygenase activity in fetal livers.

Adult↗
PubMed1988

Effects of age and chronic renal failure on the urinary excretion kinetics of famotidine in man.

The plasma and urine concentrations of famotidine, a new, potent H2-receptor antagonist, have been measured in 16 healthy young adults, 8 healthy elderly people and 18 patients with varying degrees of renal dysfunction after intravenous administration. Both the plasma elimination and renal excretion of famotidine were decreased in the elderly volunteers and renal patients. The renal clearance of famotidine averaged 4.43 ml/min/kg (310 ml/min) in normal young volunteers, which exceeded the mean creatinine clearance 1.55 ml/min/kg (109 ml/min), suggesting net secretion is a significant mechanism for elimination of famotidine. The ratio of famotidine renal clearance to creatinine clearance decreased as creatinine clearance decreased; these results suggest that the deterioration in the secretion process was much faster than that in glomerular filtration and are incompatible with the "intact nephron hypothesis". Nevertheless, both total body clearance and renal clearance were significantly correlated with creatinine clearance. The apparent half-life was also significantly correlated with creatinine clearance. Since famotidine is essentially free of dose-related adverse effects, dose adjustment in patients with mild renal insufficiency and in elderly people is not required; however, either a prolonged dosing interval or a decrease in daily dose during long-term therapy may be adapted for the patients with severe renal insufficiency to avoid accumulation and the potential undesirable effects.

Adult↗
PubMed1988

Creep in a palladium-enriched high-copper amalgam.

Palladium additions to a dispersed phase high-copper amalgam have been shown recently to suppress markedly the eta' (Cu6Sn5) concentration and decrease creep. A detailed study of the dental and 24 h creep for Pd containing high-copper amalgams and six commercial controls as a function of applied temperature and stress was performed. One part of Ag-Cu or Ag-Cu-Pd dispersants with substitutions of up to 20wt/o Pd for either Ag or Cu was blended with two parts of traditional amalgam alloy. Various temperatures from 25 to 60 degrees C and stresses from 36 to 72 MPa were applied to the samples during the test. For commercial controls and experimental amalgams with no Pd, creep is a strong function of temperature and stress. The experimental amalgam containing up to 10wt/o Pd, Pd substituted for Ag, demonstrated essentially constant creep over the temperature and stress range applied.

Chemical Phenomena↗
PubMed1988

Changing patterns of genital herpes simplex virus infections.

Herpes simplex virus type 2 is considered by many venereologists as the predominant serotype among those patients suffering from genital herpes. However, identification of genital isolates obtained from 16 through 20, and 31 through 40 year old individuals among our female patient population shows a predominance of HSV-1 infections. These data suggest that the "above the waist"-"below the waist" epidemiologic patterns commonly ascribed to reflect a prevalence of HSV-1 and HSV-2 infections respectively, may no longer be appropriate in certain patient populations.

Adolescent↗
PubMed1988

Genetic transformation in Lactobacillus sp. strain 100-33 of the capacity to colonize the nonsecreting gastric epithelium in mice.

Lactobacillus isolates able to colonize the surfaces of the nonsecreting epithelia in the stomachs of monoassociated ex-germfree mice were derived from Lactobacillus acidophilus 100-33. Strain 100-33 was originally isolated from pig feces and is unable to colonize the murine gastric epithelium. In experiments involving attempts genetically to transform the capacity to colonize the epithelium, cells of strain 100-33 were treated with muralytic enzymes and mixed with polyethylene glycol and genomic or plasmid DNA extracted from Lactobacillus fermentum RI. Strain RI was originally isolated from a conventional mouse and has the capacity to colonize the nonsecreting gastric epithelium. The mixtures containing cells, polyethylene glycol, and DNA were plated on a regeneration medium. After overnight incubation, the cells were washed from the plates and introduced by gastric gavage into germfree mice. Only mice that received regenerated 100-33 cells previously mixed with genomic DNA from strain RI had layers of gram-positive bacteria on the keratinized epithelia of their stomachs. Six isolates cultured from the washed gastric tissues of these animals were characterized. When a culture of each or a pool of cultures of the six were orally administered to germfree mice, layers of gram-positive bacterial cells were visible on the keratinized gastric epithelia of the animals within 1 to 3 weeks. Cells of all six, but not of strain 100-33, reacted with antibody made in rabbits to L. fermentum RI cells, as determined by an enzyme-linked immunosorbent assay. Nevertheless, all six had fermentation profiles identical to that of strain 100-33.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Control of preweaning diarrhea in piglets by acupuncture and Chinese medicine.

Preweaning diarrhea in piglets is a very common disease. Even thought vaccination and antibiotics are used widely for controlling the disease nowadays, it is still a serious production problem. Therefore, the search for a new medication that is both cheaper and more effective is of major importance. During the last year, acupuncture and Chinese medicine have been evaluated for this purpose. The results are summarized as follows: 1) Oral administration of 0.5 g of Ko-ken-huang-lien-huang-chin-tang (pueraria, coptis, scute and licorice combination) to piglets at 1 day old was effective in reducing incidence of infection (P less than 0.1) and increasing the body weight gain (P less than 0.05) during the first 10 days of life. Gentamycin or aqua-acupuncture at day 1 of life had no prophylactic value. 2) Piglets with preweaning diarrhea were treated by aqua-acupuncture at Chang-Chiang point (VG 1, or so called Chiao-Chao in traditional pig charts) with 0.2 ml of 3% saline, or by oral administration of 0.5 g of Ko-ken-huang-lien-huang-chin-tang or by injection of gentamycin (10 mg/piglet) twice a day for 1-3 days. These treatments significantly reduced the duration of illness (P less than 0.01) when compared with the control groups which received 0.5 g lactose orally. These results indicate that both acupuncture treatment and Chinese medicine have a high clinical value for controlling piglet diarrhea.

Acupuncture Therapy↗
PubMed1988

Effects of electroacupuncture and gonadotropin-releasing hormone treatments on hormonal changes in anoestrous sows.

The therapeutic effects of acupuncture in treating reproductive disturbances of man and animals have been proven in the past and is used clinically already. However, the mechanism of such therapy is not known yet. In this study, anoestrous sows were used to investigate the mechanism. Anoestrous sows with luteal ovaries were allocated to three groups. Four sows received electroacupuncture treatment at Pai-Hui and Wei-Ken (acupuncture treated group; group 1). Three sows received electroacupuncture treatment at Chiang-Feng and Chou-Shu (acupuncture control group; group 2). Four received 50 micrograms of gonadotropin-releasing hormone (GnRH) intravenously (drug control group; group 3). The concentrations of luteinizing hormone, progesterone, oestradiol and cortisol in serum were measured by radioimmunoassay. Oestrus return was monitored during 14 days after treatment. At the end of this observation period, the number of animals returned to oestrus were 3, 1 and 1 in groups 1, 2 and 3, respectively. It suggests that only treatment with acupuncture at Pai-Hui and Wei-Ken had therapeutic effects in inducing oestrus. This finding is further supported by the changes of serum sex hormone concentrations. Serum LH concentrations decreased for about 2 hours after electro-acupuncture treatment both in groups 1 and 2, whereas those in group 3 increased sharply at 10 minutes, reached to a peak at 20 minutes and returned gradually to basal level between 4 and 6 hours after GnRH injection. Serum progesterone concentrations rose between 4 to 6 hours after treatment in groups 1 and 3 but not in group 2. Five sows become oestrus, showed a decreased progesterone level 2 days after treatments whereas the other six anoestrous sows did not. Oestradiol levels did not have meaningful changes during the blood sampling period of 5 to 7 days in these 3 groups. Cortisol levels elevated in 15 minutes after the electroacupuncture in groups 1 and 2. However, the increment of cortisol induced by the electroacupuncture was less than that induced by the first bleeding, indicating that the adrenal stimulation may not be the main reason of the therapeutic action. The results indicated that the electroacupuncture treatment and GnRH injection could alter the release of LH from the pituitary in different ways but only electroacupuncture at Pai-Hui and Wei-Ken has a specific action on ovary and a significant therapeutic effect. Therapeutic effects of electroacupuncture on reproductive disturbance may involve a synergism of somatic-ovary and uterus reflex and central nervous-endocrine system (the hypothalamo-pituitary-ovary axis).

Acupuncture Therapy↗
PubMed1988

Renal handling of drugs in renal failure. I: Differential effects of uranyl nitrate- and glycerol-induced acute renal failure on renal excretion of TEAB and PAH in rats.

Two etiologically different models of experimental acute renal failure were induced in rats by administration of either glycerol or uranyl nitrate. Both compounds caused a substantial decrease in the glomerular filtration rate (GFR) and the net tubular secretion of tetraethylammonium bromide (TEAB) and para-aminohippuric acid (PAH). The degree of renal impairment induced by uranyl nitrate and glycerol appeared to be dose related. Deprivation of drinking water 24 hr before the administration of glycerol potentiated the renal damage. In uranyl nitrate-induced renal failure, the decline of the net tubular secretion for TEAB and PAH was not proportional to the decrease in GFR; the secretion process deteriorated faster than the GFR. For example, when 0.5 mg/kg uranyl nitrate was administered, GFR fell to approximately 65% of normal, whereas the net tubular secretion was decreased to 30% of normal. These results suggest that the tubular transport was preferentially affected by uranyl nitrate. In contrast, in glycerol-induced renal failure, the decline of TEAB secretion fell in a parallel fashion with the GFR, suggesting that the glomeruli and the proximal tubules were equally damaged by glycerol. However, in this latter model, the decline of PAH secretion did not parallel the decrease in GFR, contradicting the proposal that glycerol affects equally the glomeruli and the proximal tubules. This discrepancy may be due to the selective competitive inhibition of PAH secretion by the accumulation of naturally occurring organic acids.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗
PubMed1987

Biotransformation of sulindac in end-stage renal disease.

In normal humans sulindac, a prodrug, undergoes two major biotransformations: irreversible oxidation to the inactive sulfone metabolite and reversible reduction to the pharmacologically active sulfide metabolite. To assess any effect of end-stage renal failure on sulindac biotransformation, six patients were given 200 mg sulindac orally. Plasma was sampled over 24 hours. Protein binding of sulindac and metabolites was determined by equilibrium dialysis. Results were compared with historic controls. AUC(0-12) for sulindac and the sulfone were similar to controls. AUC(0-12) for the sulfide was significantly reduced to 4.85 micrograms X hr/ml from 13.1 micrograms X hr/ml (P less than 0.02). Protein binding of all three compounds was significantly reduced by renal failure. When corrected for protein binding, the AUC(0-12) for sulindac and the sulfone was twice that of controls whereas that of the sulfide was 42 ng X hr/ml compared with 83 ng X hr/ml in normal individuals (P less than 0.001). This suggests that end-stage renal failure impairs the reduction of sulindac to the active sulfide whereas oxidation to the sulfone is intact.

Administration, Oral↗
PubMed1987

Effects of antacids and food on absorption of famotidine.

The effect of a high potency antacid and food on the bioavailability of famotidine was studied in 17 healthy volunteers in an open randomized three-way cross-over trial. After an overnight fast, famotidine was administered to each subject as follows: 40 mg famotidine orally alone; 40 mg orally with antacid; and 40 mg orally with a standard breakfast. Coadministration of the antacid caused a small but significant reduction in the maximum plasma concentration (Cmax) of famotidine from 81.1 +/- 54.2 to 60.8 +/- 21.6 ng ml-1 (P less than 0.05) and a small decrease in the area under plasma concentration-time curve [AUC] from 443.3 +/- 249.2 to 355.0 +/- 125.1 ng ml-1 h (P greater than 0.05). However, there was only a minimal effect of food on these parameters; the Cmax and [AUC] were 81.6 +/- 29.6 ng ml-1 and 434.8 +/- 145.9 ng ml-1 h, respectively.

Antacids↗
PubMed1987

Comparative effect of famotidine and cimetidine on the pharmacokinetics of theophylline in normal volunteers.

The comparative effect of famotidine or cimetidine on theophylline disposition was determined in healthy volunteers. Cimetidine, but not famotidine, caused a reduction in the rate of elimination of theophylline. The mean total body clearance of theophylline was reduced from 57.6 ml min-1 before cimetidine to 39.5 ml min-1 during cimetidine; and the half-life was prolonged from 8.7 h before cimetidine to 12 h during cimetidine. The volume of distribution and renal excretion of theophylline were not affected by either famotidine or cimetidine.

Cimetidine↗
PubMed1987

Protein binding as a primary determinant of the clinical pharmacokinetic properties of non-steroidal anti-inflammatory drugs.

The ability of a wide variety of anionic, cationic, and neutral drugs to bind in a reversible manner to plasma proteins has long been recognised. Non-steroidal anti-inflammatory drugs (NSAIDs) are distinguished as a class by the high degree to which they bind to plasma protein. Plasma protein binding properties are primary determinants of the pharmacokinetic properties of the NSAIDs. Theoretical relationships are reviewed in order to define quantitatively the impact of plasma protein binding on clearance, half-life, apparent volume of distribution, and the duration and intensity of pharmacological effect. The quantitative relationships governing competitive displacement binding interactions are also presented. Experimental methods for in vitro and in vivo determination of the degree of plasma protein binding are discussed. The more common in vitro methods are equilibrium dialysis and ultrafiltration. Methods for characterising the degree of plasma protein binding in vivo consist of either measuring the concentration of drug at equilibrium in an implanted semipermeable vessel or measuring the relative drug concentrations in two body spaces with different protein content. Emphasis is given to the comparative advantages and disadvantages of experimental application of the various in vitro and in vivo methods. Plasma protein binding is discussed as a determinant of the trans-synovial transport of NSAIDs. Trans-synovial transport of NSAIDs appears to be a diffusional process. Limited data in humans receiving ibuprofen, indomethacin, aspirin, carprofen, alclofenac, or diclofenac suggest that clearance of each of these NSAIDs from the synovium is slower than clearance from plasma. The clinical data relevant to the relationship between plasma NSAID concentration and various measures of anti-inflammatory effect are reviewed. A positive correlation between plasma NSAID concentration and anti-inflammatory effect has been observed in only one study on naproxen and one study on piroxicam. In several other studies, the lack of concentration-response correlations is generally attributed to the relatively subjective, quantitatively inexact methods used to assess anti-inflammatory effect and analgesia in arthritic patients, as well as the substantial interpatient variabilities in the fraction of unbound NSAID and the unbound plasma NSAID concentration. In view of the generally poor correlation between concentration and therapeutic response, routine therapeutic monitoring of total plasma NSAID concentration is not recommended as a means of titrating individual dosages to the desired effect in each patient.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Inflammatory Agents, Non-Steroidal↗