scholarly journals Pharmacokinetics of Ampicillin and Sulbactam in Pediatric Patients

1999 ◽  
Vol 43 (5) ◽  
pp. 1225-1229 ◽  
Author(s):  
Milap C. Nahata ◽  
Vijay I. Vashi ◽  
Robert N. Swanson ◽  
Michael A. Messig ◽  
Menger Chung
Keyword(s):  
High Performance ◽  
Pediatric Patients ◽  
Age Groups ◽  
Total Clearance ◽  
Steady State Distribution ◽  
State Distribution ◽  
Abdominal Infection ◽  
Multiple Blood ◽  
The Mean ◽  
Intra Abdominal Infection

ABSTRACT Intravenous ampicillin-sulbactam is effective in the treatment of various infections in adults, but little is known about the pharmacokinetics (PK) of ampicillin-sulbactam in children. The objective of this study was to determine the PK of ampicillin and sulbactam in pediatric patients with intra-abdominal infection, skin and/or skin structure infection, or periorbital-preseptal and facial cellulitis. Intravenous ampicillin and sulbactam (2:1), 40 to 80 mg/kg of body weight, were given every 6 h for 2 to 6 days to 28 pediatric patients. The ages ranged from 1 to 6 years for 10 patients, 6.1 to 10 years for 9 patients, and 10.1 to 12 years for 9 patients. Multiple blood samples were obtained and analyzed for ampicillin and sulbactam in plasma and serum by high-performance liquid chromatography. The mean maximum concentration of drug in serum ranged from 177 to 200 μg/ml for ampicillin and 82 to 102 μg/ml for sulbactam in the three age groups. The mean total clearance, steady-state distribution volume, and half-life were 4.76 ml/min/kg, 0.32 liter/kg, and 0.77 h, respectively, for ampicillin and 4.95 ml/min/kg, 0.34 liter/kg, and 0.81 h, respectively, for sulbactam. Dose or gender did not affect the PK of ampicillin or sulbactam. The PK of ampicillin and sulbactam in these patients were comparable to those reported in adults. The combination was well tolerated in pediatric patients.

Increased teniposide clearance with concomitant anticonvulsant therapy.

1992 ◽  
Vol 10 (2) ◽  
pp. 311-315 ◽  
Author(s):  
D K Baker ◽  
M V Relling ◽  
C H Pui ◽  
M L Christensen ◽  
W E Evans ◽  
...  
Keyword(s):  
High Performance ◽  
Pediatric Patients ◽  
Plasma Concentrations ◽  
Substantial Reduction ◽  
Systemic Exposure ◽  
Pharmacokinetic Interaction ◽  
Lymphocytic Leukemia ◽  
Control Group ◽  
Systemic Clearance ◽  
The Mean

PURPOSE A possible pharmacokinetic interaction between teniposide and anticonvulsant medications was evaluated in pediatric patients. PATIENTS AND METHODS The systemic clearance of teniposide was determined in six pediatric patients with acute lymphocytic leukemia receiving concomitant therapy with anticonvulsants. Clearance was then compared with a control group of patients treated with the same protocol therapy and matched for age at diagnosis, sex, and race but not receiving anticonvulsants or other agents known to induce hepatic metabolism or alter protein binding of drugs. Eight blood samples were obtained during and after 4-hour infusions of teniposide, and plasma concentrations were measured by a specific high-performance liquid chromatography (HPLC) assay. A two-compartment model was fitted to each subject's data. RESULTS The mean systemic clearance (range) for the six anticonvulsant-treated patients studied during 22 courses of therapy was 32 mL/min/m2 (range, 21 to 54 mL/min/m2), significantly higher (P less than .001) than the mean value of 13 mL/min/m2 (range, 7 to 17 mL/min/m2) for the control patients studied during 26 courses of therapy. Clearance estimates for control patients were similar to previously published values for pediatric patients. CONCLUSION These data indicate that the systemic clearance of teniposide is consistently increased two- to three-fold by concomitant phenobarbital or phenytoin therapy. The consequent substantial reduction in systemic exposure may reduce teniposide's efficacy.

scholarly journals Analysis of incapacitation during +Gz induced loss of consciousness

2021 ◽  
Vol 65 ◽  
pp. 91-96
Author(s):  
MD Sharma ◽  
P Biswal ◽  
N Taneja ◽  
A Agarwal
Keyword(s):  
Air Force ◽  
High Performance ◽  
Age Groups ◽  
Rapid Onset ◽  
Loss Of Consciousness ◽  
Video Recordings ◽  
Operational Capabilities ◽  
Significant Difference ◽  
The Mean ◽  
The Difference

Introduction: Occurrence of G induced loss of consciousness (G-LOC) during centrifuge training is a known entity. The Indian Air Force is currently undertaking high G training of its fighter pilots in High Performance Human Centrifuge (HPHC) which has significantly higher operational capabilities. The study aimed to analyse the incapacitation periods and myoclonic jerks associated with G-LOC occurring during HPHC training. Material and Methods: Records of episodes of 161 G-LOC during closed loop Rapid Onset Rates (ROR) runs over a period of 7 years from 2011 to 2017 were analyzed. The video recordings of these G-LOC episodes were assessed in terms of the participant demographics, +Gz onset rates, incapacitation periods, and presence or absence of myoclonic jerks during the G-LOC episodes. Descriptive statistics was applied to analyze the incapacitation periods and the duration of the myoclonic flail movements. Single tailed t-test was used to analyze the difference between the incapacitation periods of the aircrew who suffered myoclonic flail movements and those who did not. One-way ANOVA was carried out to assess the differences in incapacitation periods, if any, between aircrew of different age groups. Significance was set at P < 0.05. Results: Of these 161 episodes of G-LOC, 43.5% were seen in trainee aircrew. The mean Absolute Incapacitation Period (AIP), Relative Incapacitation Period (RIP) and Total Incapacitation Period (TIP) was 6.9 ± 2.3 s, 12.2 ± 4.7 s, and 19.1 ± 5.5 respectively. Age and flying experience did not show any significant effect with any of the incapacitation periods (p>0.05). The TIP correlated better with the RIP than with the AIP (Pearson’s correlation values of 0.9 and 0.52 respectively). Myoclonic flail movements were witnessed in 25.5% of G-LOC episodes with an average duration of 5.3 s and more than 50% occurring at ≥8Gz. The mean duration of RIP was significantly higher (P=0.03) when G-LOC was associated with myoclonic flail movements, whereas, the duration of AIP did not show any significant difference. Conclusion: The shorter incapacitation periods observed in the study compared to that reported in most of the previous studies could be attributed to the faster Gz offset rates of the present HPHC. Episodes of G-LOC having myoclonic movements were found to have higher relative incapacitation periods. Even though these movements were associated with G-LOC occurring at higher Gz levels, the durations were independent of the Gz levels.

scholarly journals Vitamin D Levels of Out-Patients in Lithuania: Deficiency and Hypervitaminosis

Medicina ◽  
2018 ◽  
Vol 54 (2) ◽  
pp. 25 ◽  
Author(s):  
Andrius Bleizgys ◽  
Jevgenij Kurovskij
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
High Performance ◽  
Age Groups ◽  
Vitamin D Status ◽  
Cross Sectional ◽  
Hydroxyvitamin D ◽  
Vitamin D Levels ◽  
The Mean ◽  
Almost All

Aim: Data on the prevalence of vitamin D deficiency in Lithuania are scarce. The aim was to assess the reserves of vitamin D in different age groups of out-patients, regarding the season of the year. Methods: Data on serum 25-hydroxyvitamin D (25(OH)D) levels from blood tests made in 2012–2014 were obtained from one laboratory, and a retrospective cross-sectional analysis was performed. Results: A total of 9581 subjects were included. The mean age of the participants was 33 ± 23 years. The mean levels of vitamin D were higher in males than in females (p < 0.001). The highest mean 25(OH)D levels were in 0–9-year-old group, the lowest were in the 10–19-year-old group and in the group of participants that were 70 years and older (p < 0.001). The lowest vitamin D status was found in January, February, March, and April. The highest status was found in August and September. Overall, vitamin D deficiency, sufficiency, and hypervitaminosis were detected in 67%, 21%, and 12% of cases, respectively. Most cases with hypervitaminosis were in the group of children up to 2 years of age. Conclusion: Vitamin D status demonstrated clear seasonality. Significant sex-related differences of vitamin D statuses were also determined. Vitamin D deficiency was very prevalent in almost all age groups. Young children (aged up to 2 years) are of special interest for further research involving other types of 25(OH)D assays, such as those based on high-performance liquid chromatography (HPLC), since the real prevalence of “true” vitamin D hypervitaminosis in Lithuania’s children is still to be determined.

Exponential trends of first-passage-time densities for a class of diffusion processes with steady-state distribution

1985 ◽  
Vol 22 (3) ◽  
pp. 611-618 ◽  
Author(s):  
A. G. Nobile ◽  
L. M. Ricciardi ◽  
L. Sacerdote
Keyword(s):  
Asymptotic Behavior ◽  
Steady State ◽  
Diffusion Processes ◽  
First Passage Time ◽  
Passage Time ◽  
Steady State Distribution ◽  
State Distribution ◽  
First Passage ◽  
The Mean

The asymptotic behavior of the first-passage-time p.d.f. through a constant boundary is studied when the boundary approaches the endpoints of the diffusion interval. We show that for a class of diffusion processes possessing a steady-state distribution this p.d.f. is approximately exponential, the mean being the average first-passage time to the boundary. The proof is based on suitable recursive expressions for the moments of the first-passage time.

scholarly journals A sample path approach to mean busy periods for Markov-modulated queues and fluids

1994 ◽  
Vol 26 (4) ◽  
pp. 1117-1121 ◽  
Author(s):  
Søren Asmussen ◽  
Mogens Bladt
Keyword(s):  
Time Reversal ◽  
Busy Period ◽  
Fluid Model ◽  
Sample Path ◽  
Steady State Distribution ◽  
State Distribution ◽  
Additive Process ◽  
Markov Additive Process ◽  
The Mean ◽  
Markov Modulated

The mean busy period of a Markov-modulated queue or fluid model is computed by an extension of the time-reversal argument connecting the steady-state distribution and the maximum of a related Markov additive process.

scholarly journals Assessment of radiation dose to pediatric patients during routine digital chest X-ray procedure in a government medical centre in Asaba, Nigeria

2021 ◽  
Vol 8 (3) ◽  
pp. 155-160
Author(s):  
Asogwa Chijioke Obiora ◽  
Hyacienth Uche Chiegwu ◽  
Akintayo Daniel Omojola ◽  
Ebube Mmeli Onwughalu
Keyword(s):  
Radiation Dose ◽  
Effective Dose ◽  
Pediatric Patients ◽  
Age Groups ◽  
Absorbed Dose ◽  
Field Size ◽  
X Ray ◽  
Chest X Ray ◽  
The Mean ◽  
Risk Of Cancer

Objective: Radiation dose to pediatric patients have been widely reported, it is however necessary that imaging expert keep doses as low as possible to forestall stall long term cancer risk. This study is aimed at determining pediatric entrance surface dose (ESD), 75th percentile ESD, absorbed dose (D) and effective dose (E) for 0-15 years. Material and Methods: The study used a digital radiography (DR) unit with a grid system for each chest X-ray. The thermoluminescent dosimeter (TLD) used was encapsulated in transparent nylon, it was then attached to the patient skin (chest wall) and the second was placed directly at the posterior end of it. Results: The mean ESDs for the 4 age groups were as follows: 0- < 1 (1.54±0.74mGy), 1- < 5 (1.53±0.83mGy), 5- < 10 (0.55±0.39mGy) and 10- ≤15 (1.30±0.57mGy), with an overall mean of 1.23mGy. The 75th percentile ESD for each age group above 10 patients (excluding 5- < 10yrs) was 2.18, 2.19 and 1.75mGy respectively. The absorbed dose (D) ranged from 0.03-2.39mGy. The mean effective dose (E) for the 4 age groups was 0.18±0.03mSv. There was a good correlation between ESD and D (P = 0.001). A One-Way ANOVA shows that the field size and focus to film distance (FFD) affected the ESD and D (P < 0.001) respectively. The risk of childhood cancer from a single radiograph was of the order of (1.54-23.4) ×10-6. Conclusion: The 75th percentile ESD, E and childhood risk of cancer was higher than most studies it was compared with. The study reveals that machine parameters such as the field size and FFD played a major role in dose increase. Protocol optimization is currently needed for pediatric patients in the studied facility.

scholarly journals DISTRIBUTION OF NUCLEOTIDE DIFFERENCES BETWEEN TWO RANDOMLY CHOSEN CISTRONS IN A FINITE POPULATION

Genetics ◽  
1977 ◽  
Vol 85 (2) ◽  
pp. 331-337
Author(s):  
Wen-Hsiung Li
Keyword(s):  
Steady State ◽  
Population Size ◽  
Effective Population Size ◽  
Mutation Rate ◽  
Finite Population ◽  
Effective Population ◽  
Steady State Distribution ◽  
State Distribution ◽  
Simple Estimate ◽  
The Mean

ABSTRACT Watterson's (1975) formula for the steady-state distribution of the number of nucleotide differences between two randomly chosen cistrons in a finite population has been extended to transient states. The rate for the mean of this distribution to approach its equilibrium value is 1/2 N and independent of mutation rate, but that for the variance is dependent on mutation rate, where N denotes the effective population size. Numerical computations show that if the heterozygosity (i.e., the probability that two cistrons are different) is low, say of the order of 0.1 or less, the probability that two cistrons differ at two or more nucleotide sites is less than 10 percent of the heterozygosity, whereas this probability may be as high as 50 percent of the heterozygosity if the heterozygosity is 0.5. A simple estimate for the mean number (d) of site differences between cistrons is d = h/(1 - h) where h is the heterozygosity. At equilibrium, the probability that two cistrons differ by more than one site is equal to h  2, the square of heterozygosity.

scholarly journals Biomonitoring Study of Deoxynivalenol Exposure in Chinese Inhabitants

2019 ◽  
Vol 16 (12) ◽  
pp. 2169 ◽  
Author(s):  
Xiaodan Wang ◽  
Jiang Liang ◽  
Pei Cao ◽  
Shuang Zhou ◽  
Aibo Wu ◽  
...  
Keyword(s):  
Children And Adolescents ◽  
High Performance ◽  
Age Groups ◽  
Henan Province ◽  
Urine Samples ◽  
Exposure Level ◽  
Dietary Intakes ◽  
Liquid Chromatography Tandem Mass ◽  
Exposure Levels ◽  
The Mean

Objective: To investigate the levels of a deoxynivalenol (DON) biomarker in the urine of subjects living in two China provinces with different geographic locations and dietary patterns, and estimate their dietary DON exposures and health risks. Methods: First morning urine samples were collected on three consecutive days from 599 healthy subjects—301 from Henan province and 298 from Sichuan province—to analyze the total DON concentrations (tDON) after β-glucuronidase hydrolysis using a high-performance liquid chromatography tandem mass spectrometry-based method. The consumption of cereal foods in the previous 24 h before each urine collection was recorded using a duplicate diet method. DON exposure levels were estimated based on the urinary tDON concentrations. Results: Total DON were detected in 100% and 92% of the urine samples from Henan and Sichuan, respectively. Mean urinary tDON concentrations were 52.83 ng/mL in Henan subjects and 12.99 ng/mL in Sichuan subjects, respectively. The tDON levels were significantly higher in the urine of Henan subjects than that of the Sichuan subjects (p < 0.001). Urinary tDON levels were significantly different among age groups in both areas (Henan: p < 0.001; Sichuan: p = 0.026) and were highest in adolescents aged 13–17 years, followed by children aged 7–12 years. Based on the DON biomarker and exposure conversion reported by the European Food Safety Authority (EFSA), the mean estimated dietary intakes of DON were 1.82 μg/kg bw/day in Henan subjects and 0.45 μg/kg bw/day in Sichuan subjects. A total of 56% of Henan subjects and 12% of Sichuan subjects were estimated to exceed the PMTDI of 1 μg/kg bw/day. Consistent with urinary tDON levels, the highest estimated dietary DON intakes were also in children and adolescents aged 7–17 years. For all kinds of wheat-based foods except dumplings, the consumptions were significantly higher in Henan than those in Sichuan. The mean consumption of steamed buns was 8.4-fold higher in Henan (70.67 g/d) than that in Sichuan (8.45 g/d). The mean consumption of noodles in Henan (273.91 g/d) was 3.6-fold higher than that in Sichuan (75.87 g/d). Conclusions: The levels of urinary DON biomarker and the estimated dietary DON intakes in Henan province were high and concerning, especially for children and adolescents. The overall exposure level of Sichuan inhabitants was low.

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