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Biomedical subjects

C Kim

Publications and source records attributed to C Kim.

432 records · Page 24Linked to original sources
PubMedDate not supplied

Rapid and sensitive analysis of morphine in serum by reversed-phase high performance liquid chromatography with electrochemical detection.

A method is described for the determination of morphine in serum. Separation and quantitation are performed by reversed-phase high performance liquid chromatography with electrochemical detection. A sample size of 100 microL or less is required for detection of concentrations as low as 1 to 2 ng/mL. In trials with standard solutions, recovery was 75%. The between-run and within-run coefficients of variation were 7.3% (over the range of 5 to 200 ng/mL) and 9.1% (at 5 ng/mL), respectively.

Animals↗
PubMedDate not supplied

Characterization of natural and total artificial heart acceleration.

The pulsatile nature of an implanted total artificial heart (TAH) may have several deleterious effects. To define the level of TAH impact, acceleration was measured and compared with that of the natural heart in a series of in vivo and in vitro experiments. In TAH implantations in calves, miniature accelerometers were incorporated onto the housing of a Utah-100 left ventricle. Identical accelerometers were glued to felt pledgets to obtain measurement of radial cardiac acceleration when sewn to the epicardial surface of the natural heart. Measurement of natural and artificial heart acceleration was made both intraoperatively and postoperatively in several animals. Many pumping conditions were also investigated with a similarly instrumented UVAD 85 left ventricle during in vitro testing. The peak natural heart acceleration measured was nearly 2 g both intraoperatively and at rest. Treadmill exercise or epinephrine infusion produced twice the resting peak acceleration value of the natural heart. Artificial heart peak acceleration as great as +/- 100 g was found intraoperatively and postoperatively. Peak TAH acceleration could be reduced by allowing the ventricle to fill fully prior to the start of the next systole, by allowing the ventricle to fully eject prior to the next diastole, or by using a ventricular pressurization waveform that has a smooth contour with a sinusoidal-like profile. The ability to lower TAH acceleration may lead to a reduction in undesirable consequences of TAH implantation.

Animals↗
PubMedDate not supplied

Marital conflict in older adults: endocrinological and immunological correlates.

OBJECTIVE: To assess endocrinological and immunological correlates of marital conflict and marital satisfaction, 31 older couples (mean age 67 years) who had been married an average of 42 years were studied. METHOD: Couples were admitted to the Clinical Research Center and a catheter was placed in each subject's arm. Blood was drawn on entry for immunological assays; for hormone analyses, five blood samples were drawn during a 30-minute conflict discussion and a 15-minute recovery session. The conflict session was recorded on videotapes that were later coded for problem-solving behaviors using the Marital Interaction Coding System (MICS). RESULTS: Among wives, escalation of negative behavior during conflict and marital satisfaction showed strong relationships to endocrine changes, accounting for 16% to 21% of the variance in the rates of change of cortisol, adrenocorticotropic hormone (ACTH), and norepinephrine (but not epinephrine). In contrast, husbands' endocrine data did not show significant relationships with negative behavior or marital quality. Both men and women who showed relatively poorer immunological responses across three functional assays (the blastogenic response to two T-cell mitogens and antibody titers to latent Epstein-Barr virus) displayed more negative behavior during conflict; they also characterized their usual marital disagreements as more negative than individuals who showed better immune responses across assays. CONCLUSION: Abrasive marital interactions may have physiological consequences even among older adults in long-term marriages.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Reverse transcription-polymerase chain reaction and western blotting analysis for detection of p63 isoforms in uterine cervical cancers.

The aim of this study was to investigate the role of TAp63 and DeltaNp63 isoforms in uterine cervical cancers. The messenger RNA (mRNA) and protein expressions of TA and DeltaN forms as well as alpha, beta, and gamma isoforms of p63 were studied in seven SiHa, ME-180, SNU17, SNU902, SNU1160, SNU703, and SNU1299 human papillomavirus (HPV)-positive uterine cervical squamous cell carcinoma (SCC) cell lines, one HT3 HPV-negative SCC cell line, and one HeLa adenocarcinoma cell line using reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. Fresh nonneoplastic and neoplastic tissues of uterine cervical and endometrial cancers were also studied. RT-PCR for TA and DeltaN form and three isoforms of p63 showed positive bands for both TA and DeltaN forms and for all three isoforms in cervical cancer cell lines but weak band for alpha isoform in HPV-negative HT3 SCC cell line and no band for beta isoform in HeLa adenocarcinoma cell line. RT-PCR for TA and DeltaN and three isoforms of p63 mRNA in tissue samples showed positive bands in almost all samples, except for gamma isoform, the expression was weak or absent in nonneoplastic tissues compared with neoplastic tissues. In western blotting, cancer cell lines and both nonneoplastic and neoplastic tissue samples showed expression of TA and DeltaN, and gamma isoform but beta isoform expression with or without alpha isoform was only found in cancer cell lines and neoplastic tissues. beta isoform, possibly of DeltaNp63, may be considered as an important isoform in uterine cervical squamous cell carcinogenesis.

Biomarkers, Tumor↗
PubMedDate not supplied

Early changes of experimentally induced cerebral aneurysms in rats: scanning electron microscopic study.

To obtain information about the early changes of experimentally induced cerebral aneurysms in rats, the luminal surface of branching areas of their cerebral arteries was examined with a scanning electron microscope. At the branching sites of major cerebral arteries in the control animals, the intima just distal to the apex markedly protruded into the lumen forming a linear bank-like intimal pad. Along and distal to this pad, there was a shallow long groove (juxta-apical groove). Such grooves were much deeper and wider in experimental animals than those in the control rats. By studying various stages of early aneurysmal changes, cerebral aneurysms were proven to develop from such grooves. In deep juxta-apical grooves and small aneurysms, round regenerated endothelial cells with a large number of microvilli were diffusely present. Degenerated cells with balloons and craters were observed intermingled with such regenerated cells. Interendothelial gaps were also seen. The present study showed the complex structure of the apex of arterial bifurcation in rats, including bank-like intimal pads. Such complex structures of the branching sites were considered to be responsible for the initiation of cerebral aneurysms due to endothelial injury possibly caused by turbulent flow there.

Animals↗
PubMedDate not supplied

How do fetal grafts of the suprachiasmatic nucleus communicate with the host brain?

Fetal grafts containing the hypothalamic suprachiasmatic nucleus (SCN), the site of an endogenous circadian pacemaker, can reinstate behavioral rhythms in lesioned recipients but the precise routes of communication between the graft and the host brain remain unknown. Grafts containing the SCN may convey temporal information to the host brain via neural efferents, diffusible factors, or a combination of both. We examined graft-host connections in anterior hypothalamic homografts (hamster-to hamster) and heterografts (rat-to hamster) implanted in the third ventricle by: (a) applying the carbocyanine dye, diI, directly onto homo- and heterografts in fixed tissue sections; and (b) using a donor-specific neurofilament (NF) antibody to immunocytochemically visualize heterograft efferents. DiI applied onto either homografts or heterografts labeled relatively few graft efferents which could be followed only short distances into the host brain. In contrast, NF-labeled heterograft efferents were both more numerous and extended for longer distances into the host brain than anticipated on the basis of diI tract tracing. The results suggest that anterior hypothalamic grafts implanted in the third ventricle provide substantial input to the adjacent host hypothalamus although it is not known whether these projections arise from SCN cells or from other extra-SCN hypothalamic tissue within these grafts. Nor is it known whether these projections are functional. To determine if neural efferents are required for the restoration of rhythmicity after grafting, we have encapsulated fetal anterior hypothalamus in a permselective polymer which prevents neurite outgrowth but allows diffusible signals to reach the host brain.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Assessment of dietary exposure to trace metals in Baffin Inuit food.

Chronic metal toxicity is a concern in the Canadian Arctic because of the findings of high metal levels in wildlife animals and the fact that traditional food constitutes a major component of the diet of indigenous peoples. We examined exposure to trace metals through traditional food resources for Inuit living in the community of Qikiqtarjuaq on Baffin Island in the eastern Arctic. Mercury, cadmium, and lead were determined in local food resources as normally prepared and eaten. Elevated concentrations of mercury ( > 50 micrograms/100 g) were found in ringed seal liver, narwhal mattak, beluga meat, and beluga mattak, and relatively high concentrations of cadmium and lead ( > 100 micrograms/100 g) were found in ringed seal liver, mussels, and kelp. Quantified dietary recalls taken seasonally reflected normal consumption patterns of these food resources by adult men and women ( > 20 years old) and children (3-12 years old). Based on traditional food consumption, the average daily intake levels of total mercury for both adults (65 micrograms for women and 97 micrograms for men) and children (38 micrograms) were higher than the Canadian average value (16 micrograms). The average weekly intake of mercury for all age groups exceeded the intake guidelines (5.0 micrograms/kg/day) established by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives and Contaminants. The primary foods that contributed to metal intake for the Baffin Inuit were ringed seal meat, caribou meat, and kelp. We review the superior nutritional benefits and potential health risks of traditional food items and implications for monitoring metal contents of food, clinical symptoms, and food use.

Adult↗
PubMedDate not supplied

Rapid identification of Corynebacterium diphtheriae clonal group associated with diphtheria epidemic, Russian Federation.

We used 199 Corynebacterium diphtheriae isolated from 1995 to 1997 in Russia to evaluate the ability of random amplified polymorphic DNA (RAPD) to identify the unique clonal group that emerged there in 1990. Our data show that RAPD can reliably, reproducibly, and rapidly screen a large number of strains to identify the epidemic clonal group.

Corynebacterium diphtheriae↗
PubMedDate not supplied

Valuing Viagra: what is restoring potency worth?

CONTEXT: The use of Viagra (sildenafil) (Pfizer, New York, New York) for treating impotence has increased dramatically. However, the cost of the drug and philosophical questions about what defines a medical condition have sparked controversy over whether insurance policies should cover impotence treatment. COUNT: The utility of life with impotence at which Viagra meets the conventional criterion for cost-effectiveness (i.e., < $50,000 per quality-adjusted life-year [QALY]). CALCULATION: We solved the following equation for utility of life with impotence: [formula: see text] RESULTS: Assuming that Viagra is used twice a week and that it costs $10 per pill, the utility of life with impotence would have to be less than 0.98 (compared with quality of life without impotence) for Viagra to meet the conventional criterion for cost-effectiveness. For patients using Viagra once or three times per week, the corresponding threshold utilities for impotence were 0.99 and 0.97, respectively. CONCLUSIONS: For men whose quality of life is sufficiently diminished by impotence, Viagra would be considered cost-effective relative to other commonly used health interventions.

Cost-Benefit Analysis↗
PubMedDate not supplied

[Removal of the 3'- and 5'-untranslated region amplifies expression of the erythropoietin gene in mammalian cells].

The effect of the 5T- and 3T-untranslated regions (UTR) of human erythropoietin gene (gEpo) on its expression in mammalian cells was investigated. 5T-UTR-deleted, 3T-UTR-deleted, and 5T,3T-UTR-deleted gEpos were transfected into COS-7 cells, and the amount of transiently expressed Epo was measured. Cells transfected with the 5T,3T-UTR-deleted gEpo showed the highest expression, 2.6 times that with wild-type gEpo. Northern blot analysis indicated that the enhanced expression of 5T,3T-UTR-deleted gEpo might be related with the transcription efficiency.

3' Untranslated Regions↗
PubMedDate not supplied

Bilateral retinal venous caliber decrease following unilateral optic nerve sheath decompression.

We investigated retinal vascular changes in nine patients undergoing optic nerve sheath decompression for vision-threatening papilledema associated with pseudotumor cerebri. Two major (one superior and one inferior) retinal venous and arterial calibers were measured before and 1.1 +/- 0.1 months, 3.2 +/- 0.2 months, 5.0 +/- 0.2 months, 7.6 +/- 0.2 months, and 13.0 +/- 1.9 months after surgery. The retinal venous caliber decreased significantly, and the decrease progressed until 3.2 months after surgery. The venous caliber in the contralateral unoperated eyes also decreased significantly. The decrease in the venous caliber in the contralateral unoperated eye as well as in the operated eye following the surgery supports the hypothesis that slow filtration is the mechanism of successful optic nerve sheath decompression. Retinal venous caliber measurement, in either the operated eye or the unoperated fellow eye, can be used to quantitatively monitor the status of papilledema associated with pseudotumor cerebri.

Adult↗
PubMedDate not supplied

A comprehensive evaluation of the vial equilibration method for quantification of the metabolism of volatile organic chemicals. Trichloroethylene.

A study was undertaken, using 1,1,2-trichloroethylene (TCE), to: a) evaluate and improve the efficiency of the vial equilibration method, as first reported by Sato and Nakajima (Toxicol. Appl. Pharmacol. 47, 41-46, 1979); b) select an appropriate vehicle for the volatile substrate; c) examine the rate of metabolism of TCE by different rat hepatic microsomal preparations; d) determine TCE metabolic rate constants; and e) assess the influence of oleic acid and linoleic acid (the two major fatty acids in corn oil) on TCE metabolism. TCE was incorporated into a 1% Alkamuls aqueous emulsion and incubated with cofactors and the 10,000g supernatant or the microsomal fraction of livers of male Sprague-Dawley rats (275-325 g) in sealed headspace vials. Different trials were conducted to elucidate time-, enzyme-, and substrate-activity relationships. The apparent Km and Vmax were 2.0 microM and 1.9 nmol/mg protein/10 min for substrate concentrations ranging from 0.3 to 34 microM in the 10,000g fraction. The apparent Km and Vmax for the microsomal fraction were 4.17 microM and 8.0 nmol/mg protein/10 min, respectively. Linoleic acid concentrations of 10 microM and higher reduced TCE metabolism by the 10,000g fraction, whereas oleic acid concentrations of 50 microM and higher were required to inhibit TCE metabolism. Isooctane and dimethylsulfoxide caused a significant decrease in TCE metabolism. The vial equilibrium technique, as described herein, is relatively simple, rapid, and reliable, and may be applicable as a standard procedure for quantifying volatile organic chemical metabolism by different tissues of different species, including humans.

Animals↗
PubMedDate not supplied

Soluble interleukin 2 receptors in patients with Bell's palsy.

The etiology and pathogenesis of Bell's palsy are still an enigma. Some studies have reported about the presence of cellular and humoral immune dysfunction in this disease. Recently, determination of soluble interleukin 2 receptor has proven to be a valuable clinical tool to detect dysregulation of T lymphocyte function. The concentrations of soluble interleukin 2 receptor alpha was determined in serum samples from 11 patients with Bell's palsy by an enzyme linked immunosorbent assay (ELISA). Concomitantly 8 age- and sex-matched healthy blood donor as well as six patients with dermatitis herpetiformis served as negative and positive controls, respectively. The concentration of soluble interleukin 2 receptor in serum samples from these patients was similar to that in samples from normal subjects. In contrast to this, patients with dermatitis herpetiformis showed higher values of interleukin 2 receptor. Our results showed that Bell's palsy is not accompanied by a massive activation of T cells.

Adolescent↗
PubMedDate not supplied

[A quantitative study of the presence of interleukin-1 and interleukin-6 in cholesteatoma of the middle ear].

Cholesteatoma of the middle ear is an inflammatory disease characterized by the presence of a keratinized squamous layer that leads to bone destruction. The process may be mediated by various factors (interleukins) produced by an activated macrophages and keratinocytes. Interleukin-1 (IL-1) and interleukin-6 (IL-6) concentrations were measured in extracts of cholesteatoma and normal tissue using the enzyme immunoassay technique (ELISA) after protein concentrations were determined. IL-1 alpha and IL-6 had higher concentrations in cholesteatoma than in normal skin and played a prominent role in bone resorption.

Bone Resorption↗