scholarly journals Pharmacokinetics of Total and Unbound Ertapenem in Healthy Elderly Subjects

2004 ◽  
Vol 48 (2) ◽  
pp. 521-524 ◽  
Author(s):  
D. G. Musson ◽  
A. Majumdar ◽  
S. Holland ◽  
K. Birk ◽  
L. Xi ◽  
...  
Keyword(s):  
Young Adults ◽  
High Performance ◽  
The Elderly ◽  
Reversed Phase ◽  
Elderly Subjects ◽  
Multiple Dosing ◽  
Time Curve ◽  
Unbound Fraction ◽  
Healthy Elderly ◽  
The Mean

ABSTRACT Ertapenem is a new once-a-day parenteral carbapenem antimicrobial agent. The pharmacokinetics of unbound and total concentrations of ertapenem in plasma were investigated in elderly subjects and compared with historical data from young adults. In a single- and multiple-dose study, healthy elderly males and females (n = 14) 65 years old or older were given a 1-g intravenous (i.v.) dose once daily for 7 days. Plasma and urine samples collected for 24 h on days 1 and 7 following administration of the 1-g doses were analyzed by reversed-phase high-performance liquid chromatography. Areas under the concentration-time curve from 0 h to infinity (AUC0-∞) for elderly females and males were similar following administration of 1-g single i.v. doses, and thus, the genders were pooled in subsequent analyses. Concentrations in plasma and the half-life of ertapenem were generally higher and longer, respectively, in elderly subjects than in young adults. The mean AUC0-∞ of total ertapenem in the elderly was 39% higher than that in young subjects following administration of a 1-g dose. The differences were slightly greater for the mean AUC0-∞ of unbound ertapenem (71%). The unbound fraction of ertapenem in elderly subjects (∼5 to 11%) was generally greater than that in young adults (∼5 to 8%). As in young adults, ertapenem did not accumulate upon multiple dosing in the elderly. The pharmacokinetics of ertapenem in elderly subjects, while slightly different from those in young adults, do not require a dosage adjustment for elderly patients.

scholarly journals Comparison of Compositions and Metabolic Activities of Fecal Microbiotas in Young Adults and in Antibiotic-Treated and Non-Antibiotic-Treated Elderly Subjects

2004 ◽  
Vol 70 (10) ◽  
pp. 6113-6122 ◽  
Author(s):  
Emma J. Woodmansey ◽  
Marion E. T. McMurdo ◽  
George T. Macfarlane ◽  
Sandra Macfarlane
Keyword(s):  
Young Adults ◽  
Species Diversity ◽  
Bifidobacterium Longum ◽  
The Elderly ◽  
Elderly Subjects ◽  
Bifidobacterium Adolescentis ◽  
Healthy Elderly ◽  
Molecular Events ◽  
Metabolic Activities ◽  
Clostridial Species

ABSTRACT The colonic microbiota mediates many cellular and molecular events in the host that are important to health. These processes can be affected in the elderly, because in some individuals, the composition and metabolic activities of the microbiota change with age. Detailed characterizations of the major groups of fecal bacteria in healthy young adults, in healthy elderly people, and in hospitalized elderly patients receiving antibiotics were made in this study, together with measurements of their metabolic activities, by analysis of fecal organic acid and ammonia concentrations. The results showed that total anaerobe numbers remained relatively constant in old people; however, individual bacterial genera changed markedly with age. Reductions in numbers of bacteroides and bifidobacteria in both elderly groups were accompanied by reduced species diversity. Bifidobacterial populations in particular showed marked variations in the dominant species, with Bifidobacterium angulatum and Bifidobacterium adolescentis being frequently isolated from the elderly and Bifidobacterium longum, Bifidobacterium catenulatum, Bifidobacterium boum, and Bifidobacterium infantis being detected only from the healthy young volunteers. Reductions in amylolytic activities of bacterial isolates in healthy elderly subjects and reduced short-chain fatty acid concentrations supported these findings, since bifidobacteria and bacteroides are important saccharolytic groups in the colon. Conversely, higher numbers of proteolytic bacteria were observed with feces samples from the antibiotic-treated elderly group, which were also associated with increased proteolytic species diversity (fusobacteria, clostridia, and propionibacteria). Other differences in the intestinal ecosystem in elderly subjects were observed, with alterations in the dominant clostridial species in combination with greater numbers of facultative anaerobes.

scholarly journals Protein requirements and ageing: metabolic demand and efficiency of utilization

1997 ◽  
Vol 77 (5) ◽  
pp. 685-702 ◽  
Author(s):  
A. Fereday ◽  
N. R. Gibson ◽  
M. Cox ◽  
P. J. Pacy ◽  
D. J. Millward
Keyword(s):  
Young Adults ◽  
The Elderly ◽  
The Body ◽  
Elderly Subjects ◽  
Metabolic Demand ◽  
Protein Requirement ◽  
Body Protein ◽  
Protein Requirements ◽  
Leucine Oxidation ◽  
Healthy Elderly

The protein requirements of the elderly were investigated with [13C]leucine balance studies of metabolic demand, the efficiency of postprandial protein utilization (PPU) and the consequent apparent protein requirement. Ten elderly subjects aged 68–91 years (five men and five women) and ten young adult subjects aged 21–31 years (five men and five women) were infused with L-[1-13C]leucine for 9h commencing in the postabsorptive state (0–3h), continuing during the half-hourly feeding of low-protein meals (LP; protein 3% energy, 3–6 h), and during similar feeding of isoenergetic higher protein meals (HP; protein 15% energy, 6–9h). Leucine oxidation and balance were determined from plasma [l-13C]-α-ketoisocaproate enrichment and expired 13CO2 excretion measured during the 3rd hour of each 3h period. The protein intake during the HP phase was similar to the habitual intake estimated in the subjects from 24h urinary N excretion. Metabolic demand was defined as equal to twice the body-protein equivalent of measured postabsorptive leucine oxidation. The efficiency of PPU was calculated from the increased leucine oxidation observed during feeding, and the apparent protein requirement was defined as metabolic demand/PPU and calculated in relation to both body weight (BW) and fat-free mass (FFM) determined by densitometry or bioimpedance. Metabolic demand in the young adults was 0·83g protein/kg per d; in both elderly groups it was 36% lower when expressed per kg BW and 30% lower when expressed per kg FFM. The apparent protein requirement calculated from metabolic demand and PPU was 0·99g protein/kg per d in the young adults and this was also lower in the elderly, although this was only significant in the men (0·66g per kg BW, P=0·013; 0·79g per kg FFM, P=0·02). The results show that in this group of healthy elderly adults protein requirements as assessed from leucine balance studies were either similar to or less than those of younger adults.

Walking with Visual Restrictions in Healthy Elderly and Young Adults

2002 ◽  
Vol 21 (2) ◽  
pp. 295-301 ◽  
Author(s):  
Sean Gallagher ◽  
Yves Lajoie ◽  
Michel Guay
Keyword(s):  
Young Adults ◽  
Visual Information ◽  
Older Persons ◽  
Visual Cues ◽  
Elderly Population ◽  
The Elderly ◽  
Elderly Subjects ◽  
Elderly Persons ◽  
Experimental Conditions ◽  
Healthy Elderly

ABSTRACTVisual requirements for a simple walking task were evaluated for young and elderly persons to determine if, with normal aging, elderly subjects require more visual information. Ten young adults and 10 elderly people were asked to complete a simple walking task within predetermined pathway boundaries under two conditions of visual restriction. In the reactive condition, subjects automatically received a 200 ms flash of visual information at the halfway point of the walkway. For the predictive condition, subjects did not receive any visual information during the walking trial, but were equipped with an emergency button that would provide 200 ms of visual information whenever they needed it. For both experimental conditions, subjects received additional flashes of visual information if they stepped out of the walkway boundaries. Results showed that older persons stepped out of bounds more often in the reactive condition and gave themselves more visual cues than the younger subjects in the predictive condition. The relative importance of vision during locomotion seems to be higher in the elderly population when compared to young adults.

scholarly journals Comparative study of pharmacokinetics of two new fluoroquinolones, balofloxacin and grepafloxacin, in elderly subjects.

1996 ◽  
Vol 40 (12) ◽  
pp. 2824-2828 ◽  
Author(s):  
O Kozawa ◽  
T Uematsu ◽  
H Matsuno ◽  
M Niwa ◽  
S Nagashima ◽  
...  
Keyword(s):  
Drug Concentration ◽  
The Elderly ◽  
Plasma Drug Concentration ◽  
Elderly Subjects ◽  
Maximum Plasma ◽  
Plasma Drug ◽  
Urinary Recovery ◽  
Time Curve ◽  
Younger Adults ◽  
Healthy Elderly

Comparative pharmacokinetics and tolerability were studied in healthy elderly volunteers for two new fluoroquinolones, balofloxacin (Q-35) and grepafloxacin (OPC-17116), the main excretion routes being the renal and hepatic routes, respectively. Both agents were well tolerated in elderly subjects. In comparison with previously reported data from healthy younger adults, the absorption of balofloxacin was slightly delayed and urinary excretion was delayed and diminished. As a significant linear correlation was observed between renal clearance of balofloxacin and creatinine clearance, the delayed and diminished urinary recovery was attributed to the reduced renal function of the elderly subjects enrolled in the study. The absorption of grepafloxacin was also delayed, and the maximum plasma drug concentration and area under the plasma drug concentration-time curve were increased in the elderly by 31 and 48%, respectively, over those in younger adults on the basis of dose normalized to body weight. The plasma terminal elimination half-life and urinary recovery remained unchanged. Decreases in distribution volume and total body clearance in the elderly were considered to be the primary factors contributing to these differences.

Determination of itraconazole in human plasma by high-performance liquid chromatography with solid-phase extraction

2005 ◽  
Vol 42 (2) ◽  
pp. 94-98 ◽  
Author(s):  
Tadashi Ohkubo ◽  
Takako Osanai
Keyword(s):  
Plasma Concentration ◽  
High Performance ◽  
Solid Phase ◽  
Internal Standard ◽  
High Performance Liquid Chromatographic ◽  
Reversed Phase ◽  
New Method ◽  
Time Curve ◽  
The Mean

Background: A practical, simple, high-performance liquid chromatographic (HPLC) method is needed for the determination of itraconazole in clinical plasma samples. Methods: Itraconazole and bifonazole (internal standard) were extracted from plasma using a C8-bonded solid-phase cartridge, separated by C8 reversed-phase HPLC, and quantified by ultraviolet absorption at 263 nm. Results: This new method enabled the determination of itraconazole in the concentration range of 10.0-500.0 µg/L. The detection limit of itraconazole was 5.0 µg/L. The mean recovery of itraconazole added to plasma was more than 89.1%, with a coefficient of variation of less than 6.9%. We applied this method for the determination of plasma itraconazole in volunteers treated daily with a 200 mg oral capsule of itraconazole for four days. We monitored the plasma level of itraconazole for the following 24 h and obtained the mean area under the plasma concentration-time curve from 0 to 24 h (AUC0-24 ) value of 4358.9 ± 1933.4 µg h/L. Conclusion: Our new method will be clinically useful for accurately monitoring the plasma concentration of itraconazole in patients under treatment.

The influence of dynamic visual environments on postural sway in the elderly

1999 ◽  
Vol 9 (3) ◽  
pp. 197-205
Author(s):  
L.L. Borger ◽  
S.L. Whitney ◽  
M.S. Redfern ◽  
J.M. Furman
Keyword(s):  
Visual Information ◽  
Postural Sway ◽  
Center Of Pressure ◽  
Age Groups ◽  
The Elderly ◽  
Visual Scene ◽  
Elderly Subjects ◽  
Mean Velocity ◽  
Healthy Elderly ◽  
Young Subjects

Postural sway during stance has been found to be sensitive to moving visual scenes in young adults, children, and those with vestibular disease. The effect of visual environments on balance in elderly individuals is relatively unknown. The purpose of this study was to compare postural sway responses of healthy elderly to those of young subjects when both groups were exposed to a moving visual scene. Peak to peak, root mean squared, and mean velocity of the center of pressure were analyzed under conditions combining four moving scene amplitudes ( 2 . 5 ∘ , 5 ∘ , 7 . 5 ∘ , 10 ∘ ) and two frequencies of scene movement (0.1 Hz, 0.25 Hz). Each visual condition was tested with a fixed floor and sway referenced platform. Results showed that elderly subjects swayed more than younger subjects when experiencing a moving visual scene under all conditions. The elderly were affected more than the young by sway referencing the platform. The differences between the two age groups were greater at increased amplitudes of scene movement. These results suggest that elderly are more influenced by dynamic visual information for balance than the young, particularly when cues from the ankles are altered.

Fat and carbohydrate metabolism during exercise in elderly and young subjects

1996 ◽  
Vol 271 (6) ◽  
pp. E983-E989 ◽  
Author(s):  
S. Sial ◽  
A. R. Coggan ◽  
R. Carroll ◽  
J. Goodwin ◽  
S. Klein
Keyword(s):  
Young Adults ◽  
Carbohydrate Metabolism ◽  
Relative Intensity ◽  
The Elderly ◽  
Absolute Intensity ◽  
Substrate Oxidation ◽  
Carbohydrate Oxidation ◽  
Moderate Intensity ◽  
Elderly Subjects ◽  
Moderate Intensity Exercise

We evaluated the effect of aging on fat and carbohydrate metabolism during moderate intensity exercise. Glycerol, free fatty acid (FFA), and glucose rate of appearance (Ra) in plasma and substrate oxidation were determined during 60 min of cycle ergometer exercise in six elderly (73 +/- 2 yr) and six young adults (26 +/- 2 yr) matched by gender and lean body mass. The elderly group was studied during exercise performed at 56 +/- 3% of maximum oxygen uptake, whereas the young adults were studied during exercise performed at the same absolute and at a similar relative intensity as the elderly subjects. Mean fat oxidation during exercise was 25-35% lower in the elderly subjects than in the young adults exercising at either the same absolute or similar relative intensities (P < 0.05). Mean carbohydrate oxidation in the elderly group was 35% higher than the young adults exercising at the same absolute intensity (P < 0.001) but 40% lower than the young adults exercising at the same relative intensity (P < 0.001). Average FFA Ra in the elderly subjects was 85% higher than in the young adults exercising at the same absolute intensity (P < 0.05) but 35% lower than the young adults exercising at a similar relative intensity (P < 0.05). We conclude that fat oxidation is decreased while carbohydrate oxidation is increased during moderate intensity exercise in elderly men and women. The shift in substrate oxidation was caused by age-related changes in skeletal muscle respiratory capacity because lipolytic rates and FFA availability were not rate limiting in the older subjects.

scholarly journals Comparison of Plasma, Epithelial Lining Fluid, and Alveolar Macrophage Concentrations of Solithromycin (CEM-101) in Healthy Adult Subjects

2012 ◽  
Vol 56 (10) ◽  
pp. 5076-5081 ◽  
Author(s):  
Keith A. Rodvold ◽  
Mark H. Gotfried ◽  
J. Gordon Still ◽  
Kay Clark ◽  
Prabhavathi Fernandes
Keyword(s):  
Steady State ◽  
High Performance ◽  
Healthy Adult ◽  
Plasma Concentrations ◽  
Epithelial Lining ◽  
Time Curve ◽  
Epithelial Lining Fluid ◽  
Once Daily ◽  
Drug Concentrations ◽  
The Mean

ABSTRACTThe steady-state concentrations of solithromycin in plasma were compared with concomitant concentrations in epithelial lining fluid (ELF) and alveolar macrophages (AM) obtained from intrapulmonary samples during bronchoscopy and bronchoalveolar lavage (BAL) in 30 healthy adult subjects. Subjects received oral solithromycin at 400 mg once daily for five consecutive days. Bronchoscopy and BAL were carried out once in each subject at either 3, 6, 9, 12, or 24 h after the last administered dose of solithromycin. Drug concentrations in plasma, ELF, and AM were assayed by a high-performance liquid chromatography-tandem mass spectrometry method. Solithromycin was concentrated extensively in ELF (range of mean [± standard deviation] concentrations, 1.02 ± 0.83 to 7.58 ± 6.69 mg/liter) and AM (25.9 ± 20.3 to 101.7 ± 52.6 mg/liter) in comparison with simultaneous plasma concentrations (0.086 ± 0.070 to 0.730 ± 0.692 mg/liter). The values for the area under the concentration-time curve from 0 to 24 h (AUC0–24values) based on mean and median ELF concentrations were 80.3 and 63.2 mg · h/liter, respectively. The ratio of ELF to plasma concentrations based on the mean and median AUC0–24values were 10.3 and 10.0, respectively. The AUC0–24values based on mean and median concentrations in AM were 1,498 and 1,282 mg · h/L, respectively. The ratio of AM to plasma concentrations based on the mean and median AUC0–24values were 193 and 202, respectively. Once-daily oral dosing of solithromycin at 400 mg produced steady-state concentrations that were significantly (P< 0.05) higher in ELF (2.4 to 28.6 times) and AM (44 to 515 times) than simultaneous plasma concentrations throughout the 24-h period after 5 days of solithromycin administration.

Simultaneous determination of vitamins A and E and carotenoids in plasma by reversed-phase HPLC in elderly and younger subjects

1993 ◽  
Vol 39 (11) ◽  
pp. 2229-2234 ◽  
Author(s):  
Z Zaman ◽  
P Fielden ◽  
P G Frost
Keyword(s):  
Simultaneous Determination ◽  
High Performance ◽  
Ammonium Acetate ◽  
Beta Carotene ◽  
High Performance Liquid Chromatographic ◽  
Solvent Mixture ◽  
Reversed Phase ◽  
Alpha Tocopherol ◽  
Elderly Subjects

Abstract A reversed-phase high-performance liquid-chromatographic method for the simultaneous determination of retinol, alpha-tocopherol, alpha-carotene, beta-carotene, cryptoxanthin, lutein/zeaxanthin, and lycopene is described. This method was applied to plasma measurements in healthy young and elderly subjects. The plasma, deproteinized with ethanol, is extracted twice with n-hexane. After evaporation, the residue is dissolved in 50 microL of tetrahydrofuran and made up to 200 microL with ethanol. Samples (50 microL) are injected onto a 250 x 4.6 mm column of 5-microns-particle Spherisorb ODS1 (Phase Separations) that had been equilibrated with solvent mixture A:B (90:10 by vol) [A = 100 mmol/L ammonium acetate in methanol: acetonitrile (80:20 by vol) and B = 100 mmol/L ammonium acetate in water] at 2 mL/min. The analytes are eluted by running a 12-min linear gradient to 100% A; solvent A is then maintained for 10 min. Intrabatch CVs were 2.3%, 3.3%, 2.8%, 3.6%, 3.6%, and 3.0% for retinol, alpha-tocopherol, lutein/zeaxanthin, cryptoxanthin, lycopene, and beta-carotene, respectively. The corresponding interbatch CVs were 4.9%, 5.8%, 12.3%, 6.5%, 8.0%, and 3.4%.

scholarly journals Energy Requirement Equations in Elderly Patients: A Systematic Review (P01-002-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Dario Gregori ◽  
Honoria Ocagli ◽  
Corrado Lanera ◽  
Giulia Lorenzoni
Keyword(s):  
Systematic Review ◽  
Elderly Patients ◽  
Indirect Calorimetry ◽  
Gold Standard ◽  
Web Application ◽  
The Elderly ◽  
Energy Requirements ◽  
Elderly Subjects ◽  
Predictive Equation ◽  
Healthy Elderly

Abstract Objectives Elderly patients are at risk of malnutrition and need an appropriate assessment of energy requirements. In the clinical setting, predictive equations are widely used to estimate the Resting Energy Expenditure (REE). Although easy to use, these equations are not always validated for the elderly and, even if validated, they often provide different outputs of energy requirements for the same subject. This study aimed at doing a systematic review of the equations for the estimation of REE in the elderly with the final aim of developing a web-based application helping clinicians in finding out the most appropriate equation for estimating the REE for each subject. Methods The systematic review was carried out using PubMed and Scopus following PRISMA guidelines. Studies in subjects older than 65 years of age, testing the performance of a predictive equation for the estimation of REE vs. a gold standard (indirect calorimetry or doubly labeled water) were included in the review. Studies performed in critically ill elderly patients were excluded. Results The initial search identified 2035 studies. The final review included 50 studies. Included studies were mainly observational, conducted in healthy elderly subjects enrolled in the outpatient setting, and using indirect calorimetry as gold standard. The 50 studies included in the review corresponded to 189 different equations. Several parameters were included in the equations and they can be divided as following: anthropometric characteristics, body composition parameters, environmental measures, laboratory tests, presence of comorbidities, and physical activity frequency. Conclusions The assessment of the energy requirements in the elderly is crucial for the management of nutritional problems in this population group since nutritional problems are related to worse health outcomes. The present study showed a wide use of different type of equations for the estimation of REE in the elderly highlighting the need of choosing the most appropriate predictive equation according to the subject characteristics and health status. The web application that is currently under development will help clinicians in doing that. Funding Sources Unit of Biostatistics, Epidemiology and Public Health, University of Padova, Padova, Italy.

Sign in / Sign up

Export Citation Format

Share Document