Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Value of Life”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1989

Effect of age and renal function on cefonicid pharmacokinetics.

Cefonicid (15 mg/kg) was administered intravenously at a constant rate of infusion over 15 min to 10 geriatric patients (mean age, 77 years) and to 4 young subjects (mean age, 35 years). Model-dependent and noncompartmental pharmacokinetic parameters were calculated and found to be congruous; noncompartmental data are reported. Significant differences in the values for area under the curve, mean residence time, total body clearance, and renal clearance were observed between the geriatric and young groups. Mean elimination half-life values were 9.59 and 4.88 h for the geriatric and young groups, respectively. Total body and renal clearances were inversely correlated to age and directly correlated to creatinine clearance. Free fraction was not correlated to albumin concentration but was correlated exponentially to total cefonicid concentration. Despite the prolonged half-life values observed in our geriatric patients, the difference in mean trough concentrations was slight. Daily administration of a 15-mg/kg dose should provide adequate concentrations in serum and should not produce appreciable accumulation in geriatric patients.

Adult↗
PubMed1979

Kinetics of cis-dichlorodiammineplatinum.

The cancer chemotherapeutic cis-dichlorodiammineplatinum (cis-DDP) was administered to 8 patients (1-hr intravenous infusion) at a dose of 70 mg/m2. Plasma and urine concentrations of platinum were determined by flameless atomic absorption spectrometry. Measured plasma platinum concentrations revealed a biphasic clearance of platinum with half-life values of 23 min and 67 hr. Platinum values obtained 3 wk after the infusion indicated that a third excretory phase might be present. Urinary measurements showed 17 +/- 2.7% of the administered dose excreted in the first 4 hr and 23 +/- 3.9% excreted in the first 24 hr. Renal excretion appears to be predominantly by glomerular filtration. Non-protein-bound plasma platinum values were calculated and the non-protein-bound platinum was found to be rapidly and biphasically cleared from the plasma with half-life values of 8 to 10 min and 40 to 45 min.

Animals↗
PubMed1988

The use of an enzyme-linked immunosorbent assay to study the disposition of sheep digoxin-specific immunoglobulin G and Fab fragments in the rat.

An enzyme-linked immunosorbent assay was developed for the measurement of sheep digoxin-specific immunoglobulin G and Fab fragments. With the latter, two preparations were examined, one available commercially (Digibind, Wellcome) and one prepared by ourselves (DSFab). The assay exhibited a greater sensitivity towards immunoglobulin G compared with Digibind and DSFab, presumably because the Fab preparations lacked some of the sheep-specific antigens present on the whole antibody molecule. The assay was used subsequently to examine the disposition of the antibody preparations after injection of 1 mg/kg i.v. into anaesthetised bile duct-cannulated rats. The plasma distribution half-lives (1.8-3.3 min) were similar for all three preparations, but while plasma elimination half-life values for Digibind and DSFab were much the same (110-115 min), that for immunoglobulin G was longer (425 min). The shorter half-life values for Fab fragments were linked to a rate of urinary elimination 10-20 fold faster. No antibody excretion in the bile was detected. The apparent volume of distribution of immunoglobulin G was 35 ml/kg, indicating that the whole antibody was largely confined to the plasma space. The volume of distribution for Digibind or DSFab (about 46 ml/kg) was not significantly larger than that for immunoglobulin G and much smaller than the extracellular fluid volume, which was measured as 305 ml/kg. Thus the distribution of sheep Fab fragments in the rat markedly differs from that in the baboon (Smith et al., 1979) where the apparent volume of distribution approximates to the extracellular fluid volume.

Animals↗
PubMed1977

Pharmacokinetics of cefamandole in patients with renal failure.

The pharmacokinetics of cefamandole were studied in four patients with stable renal failure, two patients undergoing peritoneal dialysis, and four patients undergoing hemodialysis. Peak concentrations of cefamandole in serum were achieved 1 to 2 h after intramuscular injection in the patients with stable renal impairment, and the concentrations declined slowly, with half-life values of 12.3 to 18 h. Cefamandole was removed only very slowly by peritoneal dialysis. Hemodialysis was more efficient in removing cefamandole, with serum half-life values ranging from 3.8 to 7.9 h. The mean apparent volume of distribution of cefamandole in these 10 patients was 21.92 liters, or 31% of the body weight.

Cephalosporins↗
PubMedDate not supplied

Influence of C18 long chain fatty acids on hydrogen metabolism.

During anaerobic treatment, several microorganisms mediate a series of reactions to convert reduced compounds (electron donors) into methane. Inhibitors such as long chain fatty acids (LCFAs) can affect several anaerobic microbial populations and decrease the treatment efficiency. The effects of three C18 LCFAs on hydrogenotrophic methanogens in a flocculated mixed anaerobic culture were assessed in this study. The reaction half-life and the hydrogen versus time profiles were used to characterize the inhibition process. The half-life values and profiles were similar for controls and cultures exposed to LCFAs for 1 h. The hydrogen inhibition was a function of the exposure time and the LCFA concentration except for cultures exposed to stearic acid (SA). A statistical analysis of the reaction half-life for cultures incubated with 1,500 and 2,000 mg L(-1) LCFAs for 48 h, revealed the following inhibition trend: linoleic acid (LA) > oleic acid (OA) > SA. After 48 h of exposure, no clear inhibition trend was observed for cultures inoculated with LCFA mixtures; however, at levels of 1,500 and 2,000 mg L(-1), the reaction half-life values were less than that observed for cultures fed with only LA. Based on the reaction half-life data, all of the LCFAs except SA at threshold levels of approximately 1,500 mg L(-1) inhibited hydrogen metabolism. The greatest inhibition and, hence, the largest amount of accumulated hydrogen was observed in cultures fed with 2,000 mg L(-1) LA and incubated for 48 h.

Anaerobiosis↗
PubMed2000

End-of-life decision making: a qualitative study of elderly individuals.

OBJECTIVE: To identify the desired features of end-of-life medical decision making from the perspective of elderly individuals. DESIGN: Qualitative study using in-depth interviews and analysis from a phenomenologic perspective. SETTING: A senior center and a multilevel retirement community in Los Angeles. PARTICIPANTS: Twenty-one elderly informants (mean age 83 years) representing a spectrum of functional status and prior experiences with end-of-life decision making. MAIN RESULTS: Informants were concerned primarily with the outcomes of serious illness rather than the medical interventions that might be used, and defined treatments as desirable to the extent they could return the patient to his or her valued life activities. Advanced age was a relevant consideration in decision making, guided by concerns about personal losses and the meaning of having lived a "full life." Decision-making authority was granted both to physicians (for their technical expertise) and family members (for their concern for the patient's interests), and shifted from physician to family as the patient's prognosis for functional recovery became grim. Expressions of care, both by patients and family members, were often important contributors to end-of-life treatment decisions. CONCLUSIONS: These findings suggest that advance directives and physician-patient discussions that focus on acceptable health states and valued life activities may be better suited to patients' end-of-life care goals than those that focus on specific medical interventions, such as cardiopulmonary resuscitation. We propose a model of collaborative surrogate decision making by families and physicians that encourages physicians to assume responsibility for recommending treatment plans, including the provision or withholding of specific life-sustaining treatments, when such recommendations are consistent with patients' and families' goals for care.

Aged↗
PubMed1996

Cost-effectiveness of lumbar discectomy for the treatment of herniated intervertebral disc.

STUDY DESIGN: A cost-effectiveness analysis of lumbar discectomy based on existing efficacy data and newly gathered cost data. OBJECTIVES: For patients with herniated lumbar discs unresponsive to conservative management, surgery relieves pain more rapidly but at higher costs than continued medical therapy. We evaluated the cost-effectiveness of lumbar discectomy for these patients. SUMMARY OF BACKGROUND DATA: Effectiveness estimates were based on the results of a published trial of 126 herniated disc patients randomized to surgical or nonsurgical treatment. Quality of life values were based on a study of 83 subjects with low back pain. Treatment costs for herniated discs were estimated from insurance data for 372 patients treated surgically and 1,803 treated medically. METHODS: Efficacy results were weighted by quality of life values to estimate the quality-adjusted benefit of surgery. Cost-effectiveness was calculated in dollars per quality-adjusted year of life gained. Supplemental data sources for cost and effectiveness provided ranges for sensitivity analyses. RESULTS: Surgery increased average quality-adjusted life expectancy by 0.43 years during the decade following treatment, a benefit similar to extending a healthy life by 5 months. Reimbursements for surgical patients were $12,550 more than for medical patients. Nondiscounted and 5% discounted cost-effectiveness were $29,200 and $33,900 per quality-adjusted year of life gained. Supplemental analyses confirmed the basecase effectiveness estimates but suggested that the cost of discectomy was overestimated. Replacing the main cost estimate with one based on HMO patients lowered discectomy's cost to $12,000 per quality-adjusted life-year gained. CONCLUSION: For carefully selected patients with herniated discs, surgical discectomy is a cost-effective treatment. Discectomy's favorable cost-effectiveness results from its substantial effect on quality of life and moderate costs.

Cost-Benefit Analysis↗
PubMed1984

Heparin elimination and hemostasis in hemodialysis.

The heparin concentrations at the end of dialysis and the post-dialysis hemostasis were studied in 16 patients in a chronic hemodialysis program. In 8 of the patients, the heparin half-life values after dialysis were determined as well. The heparin doses were calculated as 90 IU/kg body-weight, administered in a standardized way. The heparin concentrations and the half-life values varied between 0.12-0.94 IU/ml and 29-114 minutes respectively, indicating that the heparin administration must be individually modelled. The hemostasis, measured by the arterial pressure times, was positively correlated to the heparin concentrations. Heparin levels less than 0.3 IU/ml were regularly associated with pressure times less than 10 minutes and no remaining heparin activity two hours after dialysis. In order to minimize the risk of both bleeding and clotting complications at the end of and after dialysis, a heparin concentration of approximately 0.25 IU/ml should be aimed for.

Adult↗
PubMed2006

Aggrecan turnover in human intervertebral disc as determined by the racemization of aspartic acid.

We have used the racemization of aspartic acid as a marker for the "molecular age" of aggrecan components of the human intervertebral disc matrix (aggregating and non-aggregating proteoglycans as well as the different buoyant density fractions of aggrecan). By measuring the D/L(Asp) ratio of the various aggrecan species as a function of age and using the values of the racemization constant, k(i), found earlier for aggrecan in articular cartilage, we were able to establish directly the relative residence time of these molecules in human intervertebral disc matrix. For A1 preparations taken from normal tissue, turnover rates of 0.059 +/- 0.01 and 0.063 +/- 0.01/year correspond to half-life values of 12 +/- 2.0 and 11.23 +/- 1.9 years for nucleus pulposus and annulus fibrosus, respectively; the turnover rates of 0.084 +/- 0.022 and 0.092 +/- 0.034/year for degenerate tissue correspond to half-life values of 8.77 +/- 2.2 and 8.41 +/- 2.8 years, suggesting increased rate of removal of small aggrecan fragments. For the large monomer, fraction A1D1, turnover is 0.13 +/- 0.04/year, corresponding to a half-life of 5.56 +/- 1.58 years, similar to 3.4 years in human articular cartilage. For the binding region (A1D6), turnover is 0.033 +/- 0.0012/year, corresponding to a half-life of 21.53 +/- 0.6 years, similar to 23.5 years in articular cartilage. A1 preparations from nucleus pulposus contain a lower proportion of aggregating proteoglycans as compared with annulus fibrosus, suggesting increased proteolytic modification in the nucleus pulposus. D/L(Asp) values in aggregating and non-aggregating proteoglycans of a 24-year-old individual show similar results, suggesting that the non-aggregating molecules are synthesized initially as aggregating proteoglycans, which thereafter undergo cleavage and detachment from hyaluronan.

Adolescent↗
PubMed1994

Slow elimination of glyburide in NIDDM subjects.

OBJECTIVE: To determine the terminal elimination half-life of glyburide in non-insulin-dependent diabetes mellitus (NIDDM) subjects after cessation of long-term treatment. RESEARCH DESIGN AND METHODS: Ten NIDDM patients (5 of each sex, 36-72 years old, without hepatic or renal disease) taking a median glyburide dose of 14 mg/day, who were to start insulin therapy because of sulfonylurea failure, were studied. Serum glyburide concentrations, measured by a newly developed selective and sensitive liquid chromatographic method, were followed from 10 to 48 h after the last glyburide dose. RESULTS: Serum glyburide levels declined in three different phases, with a terminal gamma-phase between 18 and 48 h having a mean +/- SD half-life of 15.0 +/- 6.7 h. Two patients had half-lives over 20 h. The half-life values did not correlate with fasting blood glucose, age, body weight, body mass index, or creatinine levels. The latter agrees with the assumption that glyburide is completely eliminated by metabolic transformation. Although longer than previously observed, the current half-life values are in accordance with clinical experience that glyburide is a long-acting sulfonylurea. CONCLUSIONS: The elimination of glyburide in NIDDM subjects is slower than previously reported. The long half-life adds support to the use of a once-daily dosage of glyburide. It also justifies increased caution when using this sulfonylurea.

Adult↗
PubMed1990

The clinical pharmacokinetics of single doses of estazolam.

The pharmacokinetics of estazolam were examined in 17 healthy male subjects. Plasma concentration-time profiles were compared following the oral administration of one 1-mg tablet, two 1-mg tablets, and one 2-mg tablet. No statistically significant differences were detected among the mean time of maximal plasma concentration (Tmax), maximal plasma concentration (Cmax), area under the plasma concentration-time curve from zero to 72 hours (AUC), or half-life values for the 2-mg doses. Mean Cmax was 97.7 and 98.6 ng/ml and mean Tmax was 1.9 and 1.6 hours for two 1-mg tablets and one 2-mg tablet, respectively. Proportionately decreased Cmax and AUC were observed following the 1-mg dose. Mean Cmax was 54.7 ng/ml for the 1-mg dose. Mean Tmax and elimination half-life values were similar to those observed after the 2-mg doses. The overall harmonic mean half-life was 14.4 hours.

Administration, Oral↗
PubMedDate not supplied

Influence of route of administration and dosage form in the pharmacokinetics and bioavailability of salbutamol.

The present study was carried out to define the pharmacokinetics of salbutamol sulfate administered to mongrel dogs in five pharmaceutical forms via two routes of administration. One pharmaceutical form was administered intravenously (Ventolin i.v.) while the other four were administered orally (Ventolin: immediate-release formulation, Volmax: commercial osmotic pump, SG7 and SG14: sustained-release hydrophilic matrices developed in our laboratory). We obtained a first-order release kinetic of the salbutamol from Ventolin and SG7, whereas a zero-order release kinetic was observed for SG14 and Volmax formulations. Oral bioavailability was 80% and there were neither significant differences (P > 0.05) in terms of the calculation method used (relation of the areas under the plasma level curve Loo-Riegelman, deconvolution) nor in terms of the dosage form (Ventolin Volmax, SG7 and SG14). The elimination half-life value of salbutamol was 1.2 h when administered intravenously; this parameter had a value of 3.0 h for the immediate-release formulation and ranged between 5.4 and 7.2 h in the sustained-release formulations when administered orally. These changes in the half-life value of the sustained-release formulations will allow us to modify the frequency of administration in relation to immediate-release formulations.

Administration, Oral↗
PubMed1988

[Pharmacokinetic and clinical studies of sultamicillin granule in the pediatric field].

Sultamicillin (SBTPC) is a combined drug of ampicillin (ABPC) and sulbactam (SBT) which is an inhibitor of beta-lactamase, in a clinical form of tosylate with equivalent molecules in ester linkages. A tablet form of this combined drug has been released since July, 1987 in Japan and now a granular form for pediatric patients has been developed. Hence, the granular form of SBTPC was administered to 6 boys (age: 8 years 5 months-11 years 5 months) to determine plasma and urinary concentrations of the drug and its urinary recovery-rates. The dose of 10 mg/kg or 15 mg/kg was given orally just after meal to 3 boys. To study clinical and bacteriological effects of this drug, a mean daily dose of 27.1 mg/kg divided 2-4 times a day was administered for 9 days on the average to a total of 57 cases with pharyngitis (5), tonsillitis (5), laryngitis (1), bronchitis (1), pneumonia (8), scarlet fever (1), typhoid fever (1), impetigo (16), furuncle (2), abscess (6), lymphadenitis (1) and urinary tract infection (10) except 2 cases which were unevaluable for clinical effects. MICs of 7 drugs (SBTPC, ABPC, SBT, methicillin (DMPPC), cloxacillin (MCIPC), cephalexin and cefaclor) against 12 of 22 strains isolated from patients with infections of skin and soft tissue were determined with inoculum-sizes of 10(8) and 10(8) CFU/ml to study beta-lactamase producing activities. Adverse reactions and abnormal effects on laboratory test values attributable to this drug were studied in patients including dropped-out cases. The results obtained are summarized as follows. 1. Mean plasma peak levels of ABPC and SBT were observed at 1 hour after administration in both of the 10 mg/kg and the 15 mg/kg groups with values of 2.34 and 5.57 micrograms/ml for ABPC and 1.87 and 4.66 micrograms/ml for SBT, respectively. Mean concentrations of SBT were lower than those of ABPC in both groups and individuals. Dose-responses in plasma levels and AUCs were observed in both groups. Mean half-life values of ABPC and SBT in the 2 groups were 1.93 and 1.12 hours for ABPC and 1.97 and 1.22 for SBT, respectively. Mean half-life values for ABPC and SBT were similar in each group and this tendency was also seen among individuals.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1983

[Benzodiazepines: significance of kinetics for therapy].

The onset and duration of action of benzodiazepines after single oral doses depend largely on absorption rate and the rate and extent of distribution. The rate and extent of accumulation during multiple dosage depend on elimination half-life and clearance. A framework is proposed for classification of benzodiazepines according to elimination half-life. Long acting benzodiazepines have half-life values usually exceeding 24 h. Drugs in this category have long-acting pharmacologically active metabolites, often desmethyldiazepam, accumulate extensively during multiple dosage, and may have impaired clearance in the elderly and those with liver disease. Intermediate and short-acting benzodiazepines have half-life values from 5-24 h and active metabolites are uncommon. Accumulation during multiple dosage is less extensive than with the long-acting group and diminishes as the half-life becomes shorter. Age and liver disease have a small influence on metabolic clearance. The half-life of ultrashort-acting benzodiazepines is less than 5 h. These drugs are essentially nonaccumulating. Pharmacokinetic classification may assist in understanding differences among benzodiazepines, but does not explain all of their clinical actions.

Age Factors↗
PubMed1981

Benzodiazepines: a summary of pharmacokinetic properties.

1 The onset and duration of action of benzodiazepines after single oral doses depend largely on absorption rate and extent of distribution, respectively. 2 The rate and extent of accumulation during multiple dosage depend on elimination half-life and clearance. A framework is proposed for classification of benzodiazepines according to elimination half-life. 3 Long-acting benzodiazepines have half-life values usually exceeding 24 hours. Drugs in this category have long-acting pharmacologically active metabolites (often desmethyldiazepam), accumulate extensively during multiple dosage, and may have impaired clearance in the elderly and those with liver disease. 4 Intermediate and short-acting benzodiazepines have half-life values from 5-24 hours. Active metabolites are uncommon. Accumulation during multiple dosage is less extensive than with the long-acting group, and diminishes as the half-life becomes shorter. Age and liver disease have a small influence on metabolic clearance. 5 The half-life of ultrashort acting benzodiazepines is less than 5 hours. These drugs are essentially non-accumulating. 6 Pharmacokinetic classification may assist in understanding of differences among benzodiazepines, but does not explain all of their clinical actions.

Anti-Anxiety Agents↗
PubMed2003

Outcome measures for clinical rehabilitation trials: impairment, function, quality of life, or value?

Choosing outcome measures in rehabilitation research depends on the standard research skills of clear thinking, attention to detail, and minimizing the amount of data collected. In rehabilitation, outcome is more difficult to measure because (1) usually several outcomes are relevant, (2) relevant outcomes are affected by multiple factors in addition to treatment, and (3) even good measures rarely reflect the specific interest of any individual patient or member of the rehabilitation team, leading to some dissent. Measurement of general quality of life is not possible because there is little agreement as to the nature of the construct; moreover, measurement of relevant aspects of quality of life would probably give similar results. Cost in terms of resources can be estimated, but there is no validated or even widely accepted method of relating this to benefit in a fair, open, and rational way. Outcome is best measured at the level of behavior (activities), with other measures being used to aid interpretation.

Clinical Trials as Topic↗
PubMed1983

Clearance rate of gonadotrophin releasing hormone in peripheral plasma of the pig.

Gonadotrophin releasing hormone was administered as an intravenous bolus injection into four boars and four ovariectomized sows. Radioimmunoassay of concentrations of gonadotrophin releasing hormone in blood collected periodically after injection indicated a biexponential decline suggesting a rapid distribution to the extracellular fluid and a slower elimination by metabolism. A mean half-life value of 2.12 +/- 0.95 (SD) minutes was calculated for the first component and of 13.15 +/- 2.55 minutes was calculated for the second component of the decline in gonadotrophin releasing hormone concentrations. No significant difference was detected between boars and sows for half-life value of either component. In the four boars, luteinizing hormone values reached a peak in plasma 20 minutes after injection and that of testosterone at 90 minutes after gonadotrophin releasing hormone treatment.

Animals↗
PubMed1985

Performance maintained by orally delivered phencyclidine under second-order, tandem and fixed-interval schedules in food-satiated and food-deprived rhesus monkeys.

Three monkeys were each tested under a second-order fixed interval (FI) schedule with fixed-ratio (FR) components, a tandem FI FR schedule and an FI schedule while either food deprived or food satiated. Under the second-order schedule, every sixteenth lip-contact response on a drinking spout produced a brief stimulus and the first FR 16 begun and completed after the 60-min interval elapsed resulted in both the brief stimulus and access to orally delivered phencyclidine. The tandem schedule was similar, except that brief-stimulus presentations during the 60-min interval were omitted, and the third schedule was an FI 60 min. The reinforcer, orally delivered phencyclidine, was available only at the end of the 60-min session. The number of drug deliveries was either "limited" (300) or "unlimited" (for 1 hr) to determine whether increased responding due to food deprivation would occur in the absence of increased drug intake. Under all conditions response rates were nearly twice as high during food deprivation as they were during food satiation. The number of phencyclidine deliveries available at the end of the session has no systemic effect on the rate of pattern of responding, but quarter-life values were consistently lower during food deprivation than they were during food satiation. Under the tandem and FI schedules, overall response rates were much lower than under the second-order schedule, and quarter-life values were higher. When water was substituted for phencyclidine under each schedule condition, response rates and liquid deliveries generally declined to below phencyclidine levels indicating that the drug had been functioning as a reinforcer.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗