scholarly journals Allometric Optimization of Enrofloxacin Dosage in Growing Male Turkeys: Empirical Evidence for Improved Internal Exposure

Antibiotics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 925
Author(s):  
Błażej Poźniak ◽  
Marta Tikhomirov ◽  
Karolina Motykiewicz-Pers ◽  
Kamila Bobrek ◽  
Marcin Świtała

Rapid weight gain in turkeys causes a major change in the pharmacokinetics of drugs, leading to age-dependent variability in the internal exposure and, possibly, treatment failure and/or selection for antimicrobial resistance in young individuals. The aim of the study was to investigate whether a non-linear dosing protocol that accounts for the previously established allometric relation between enrofloxacin clearance and body weight (BW) may optimize the internal exposure to enrofloxacin in growing male turkeys. Enrofloxacin was administered four times, between the age of 5 and 16.5 weeks, when the turkeys’ BW increased from 1.47 to 14.92 kg. Enrofloxacin was given intravenously (i.v.) or orally at the dose calculated as follows: Dose = 30 × BW0.59. After i.v. administration, the internal exposure to the drug—quantified as the area under the concentration–time curve (AUC)—was showing little age-related variation. The coefficient of variation (CV) for AUC in all individuals (15.7%) was only slightly higher than within the age groups (5.4–13.7%). After oral drug administration, CV for AUC in all individuals (22.1%) was similar as within the age groups (8.7–32.2%). These results show that intra-species allometric scaling may be efficiently implemented in the non-linear approach to enrofloxacin dosage in turkeys in order to obtain a precise internal exposure for the optimal antimicrobial effect.

Antibiotics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1057
Author(s):  
Błażej Poźniak ◽  
Marta Tikhomirov ◽  
Kamila Bobrek ◽  
Paweł Jajor ◽  
Marcin Świtała

Turkeys’ body weight (BW) increases 10-fold within only 2.5 months, leading to a change in the pharmacokinetics (PK) of drugs according to allometric principles. Thus, the same dosage may lead to age-dependent variability in efficacy, in particular, to treatment failure and/or selection for resistance. The study aimed to investigate whether a non-linear dosage based on a published allometric model for tylosin clearance, may optimize the internal exposure in growing turkeys. The single dose PK study was performed on turkeys aged 6, 9.5, 13 and 17 weeks (BW from 1.75 kg to 15.75 kg). Tylosin was administered intravenously (i.v.) or orally (p.o.) according to following protocols: Dose = 31.6 × BW0.58 or Dose = 158 × BW0.58, respectively. Plasma tylosin was measured using high-performance liquid chromatography and non-compartmental PK analysis was performed. The area under the curve (AUClast) after i.v. administration was 8.90 ± 1.01; 7.51 ± 1.11; 6.54 ± 1.20 and 8.01 ± 1.75 mg × h/L in 6-; 9.5-; 13- and 17-week-old turkeys, respectively. After p.o. administration AUClast was 4.80 ± 2.92; 4.60 ± 2.45; 3.00 ± 1.49 and 3.24 ± 2.00 mg × h/L in respective age groups indicating high variability. For i.v. administration, the non-linear dosage allowed to minimize the age-dependent variability in AUC. However, due to low oral bioavailability (8–12%) and resulting interindividual variability, the proposed approach may not improve tylosin efficacy in turkeys under farm conditions.


2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 2528-2528 ◽  
Author(s):  
W. Zamboni ◽  
L. J. Maruca ◽  
S. Strychor ◽  
B. A. Zamboni ◽  
S. Ramalingam ◽  
...  

2528 Background: STEALTH liposomes (SL), which contain lipids conjugated to polyethylene glycol (PEG), prolong the circulation time of a drug in plasma, achieve high and extended drug exposure in tumor, and are eliminated via the reticuloendothelial system (RES). S- CKD602 is a SL formulation of CKD-602, a camptothecin analogue. CKD-602 released from S-CKD602 is eliminated by the kidney. There is significant interpatient variability in the pharmacokinetic (PK) disposition of S-CKD602. Thus, there is a need to identify factors associated with the PK variability. We hypothesize that older patients (pts) have a reduced capacity to eliminate SL agents due to age-related impairment of the RES and that body composition alters the disposition of SL. Methods: PK studies of S-CKD602 were performed in a phase I study of S-CKD602 at 0.1 to 2.5 mg/m2 IV q 21 d in pts with solid tumors. Concentrations of encapsulated (E), released (R), and sum total (E + R) CKD-602 in plasma and CKD-602 in urine were measured by LC-MS/MS. Area under the plasma concentration versus time curve (AUC) was calculated and normalized by dose (AUC/dose). The ratio of total body weight to ideal body weight (TBW/IBW) was calculated as a measure of body composition. Results: Mean ± SD S-CKD602 sum total AUC/dose in pts < 60 (n = 13) and = 60 (n = 17) years of age (yo) were 4.5 ± 5.0 and 11.2 ± 11.0 (μg/ml·h)/(mg/m2), respectively (P<0.05). Controlling for age, there was a statistically significant inverse relationship between TBW/IBW and S-CKD602 AUC/dose where low TBW/IBW was associated with high AUC/dose in both age groups (P<0.05). The cumulative amount of CKD-602 recovered in the urine was 2.2-fold higher in pts < 60 yo compared with = 60 yo. Conclusions: These data suggest that pts = 60 yo have a reduced clearance of S-CKD602 and reduced release of CKD-602 from S- CKD602 compared with pts < 60 yo. In addition, pts < 60 and = 60 yo with a lean body composition may have a reduced tissue distribution and an increased plasma exposure of S-CKD602. The clinical significance of these differences and the factors associated with them need to be evaluated for S-CKD602 and other liposomal and nanoparticle anticancer agents. No significant financial relationships to disclose.


2013 ◽  
Vol 18 (3) ◽  
pp. 158-168 ◽  
Author(s):  
Emily Frankenberg ◽  
Katharina Kupper ◽  
Ruth Wagner ◽  
Stephan Bongard

This paper reviews research on young migrants in Germany. Particular attention is given to the question of how Germany’s history of migration, immigration policies, and public attitude toward migrants influence the transcultural adaptation of children and adolescents from different ethnic backgrounds. We combine past research with the results of new empirical studies in order to shed light on migrants’ psychological and sociocultural adaptation. Studies comparing young migrants and their German peers in terms of psychological well-being, life satisfaction, and mental health outcome suggest higher rates of emotional and behavioral problems among migrants of most age groups. With regard to adolescent populations between the ages of 14 and 17 years, however, the existence of differences between migrants and natives appears to be less clear. Research has also yielded inconsistent findings regarding the time trajectory of transcultural adaptation among adolescents. The coincidence of acculturation and age-related change is discussed as a possible source of these inconsistencies. Further, we provide an overview of risk and protective factors such as conflicting role expectations and ethnic discrimination, which may cause heightened vulnerability to adverse adaptation outcomes in some groups. Large-scale studies have repeatedly shown migrants of all age groups to be less successful within the German school system, indicating poor sociocultural adaptation. Possible explanations, such as the idiosyncrasies of the German school system, are presented. Our own studies contribute to the understanding of young migrants’ adaptation process by showing that it is their orientation to German culture, rather than the acculturation strategy of integration, that leads to the most positive psychological and sociocultural outcomes. The paper concludes by discussing implications for future cross-cultural research on young migrants and by suggesting recommendations for multicultural policies.


Author(s):  
A. E. Chernikova ◽  
Yu. P. Potekhina

Introduction. An osteopathic examination determines the rate, the amplitude and the strength of the main rhythms (cardiac, respiratory and cranial). However, there are relatively few studies in the available literature dedicated to the influence of osteopathic correction (OC) on the characteristics of these rhythms.Goal of research — to study the influence of OC on the rate characteristics of various rhythms of the human body.Materials and methods. 88 adult osteopathic patients aged from 18 to 81 years were examined, among them 30 men and 58 women. All patients received general osteopathic examination. The rate of the cranial rhythm (RCR), respiratory rate (RR) heart rate (HR), the mobility of the nervous processes (MNP) and the connective tissue mobility (CTM) were assessed before and after the OC session.Results. Since age varied greatly in the examined group, a correlation analysis of age-related changes of the assessed rhythms was carried out. Only the CTM correlated with age (r=–0,28; p<0,05) in a statistically significant way. The rank dispersion analysis of Kruskal–Wallis also showed statistically significant difference in this indicator in different age groups (p=0,043). With the increase of years, the CTM decreases gradually. After the OC, the CTM, increased in a statistically significant way (p<0,0001). The RCR varied from 5 to 12 cycles/min in the examined group, which corresponded to the norm. After the OC, the RCR has increased in a statistically significant way (p<0,0001), the MNP has also increased (p<0,0001). The initial heart rate in the subjects varied from 56 to 94 beats/min, and in 15 % it exceeded the norm. After the OC the heart rate corresponded to the norm in all patients. The heart rate and the respiratory rate significantly decreased after the OC (р<0,0001).Conclusion. The described biorhythm changes after the OC session may be indicative of the improvement of the nervous regulation, of the normalization of the autonomic balance, of the improvement of the biomechanical properties of body tissues and of the increase of their mobility. The assessed parameters can be measured quickly without any additional equipment and can be used in order to study the results of the OC.


1970 ◽  
Vol 4 (2) ◽  
pp. 74-77
Author(s):  
Rukshana Ahmed ◽  
Shamim Ara

Pathological changes in the prostate gland occur commonly with advancing age including inflammation, atrophy, hyperplasia and carcinoma and a change in volume is also evident. Estimation of volume of prostate may be useful in a variety of clinical settings. A cross-sectional descriptive study was designed to see the changes in volume of the prostate with advancing age and done in the Department of Anatomy, Dhaka Medical College, Dhaka from August 2006 to June 2007. The study was performed on 70 post-mortem human prostates collected from the unclaimed dead bodies that were under examination in the Department of Forensic Medicine, Dhaka Medical College, Dhaka. The samples were divided into three age groups; group A (10-20 years), group B (21-40 years) and group C (41-70 years). Volume of the sample was measured by using the ellipsoid formula. The mean ± SD volume of prostate was 7.68 ± 3.64 cm3 in group A, 10.61 ± 3.99 cm3 in group B and 15.40 ± 6.31 cm3 in group C. Mean difference in volume between group A and group C, group B and group C were statistically significant (p<0.001). Statistically significant positive correlation was found between age and volume of prostate (r = + 0.579, p < 0.001). Key Words: Prostate; volume; Bangladeshi. DOI: 10.3329/imcj.v4i2.6501Ibrahim Med. Coll. J. 2010; 4(2): 74-77


2019 ◽  
Vol 1 (8) ◽  
pp. 42-50
Author(s):  
A. V. Budkevich ◽  
L. B. Ivanov ◽  
G. R. Novikova ◽  
G. M. Dzhanumova

According to the authors, rationing the age-related EEG parameters in children should be based on personal psychical characteristics. A comparative analysis of personal psychical characteristics and electroencephalographic data was carried out in 300 apparently healthy children aged 3-15 years. According to this principle, two subgroups of conditionally healthy children in each age group were singled out: 1) with an immature attention function and 2) with an increased anxious background that do not reach the pathological level. Registration and analysis of EEG was performed by the Neurokariograf computer complex (MBN, Moscow) using mathematical processing methods.The EEG interpretation was based on the principle of assessing the functional state of a child's brain using a three-component model according to: 1) wakefulness level and its dissociation, 2) severity of signs of the EEG neurotic pattern, 3) directionality of formation of traits of the system-functional brain organization (severity of signs functional hypofrontality).lt was found the presence of EEG signs was indicative of a lower level of wakefulness in children with an immature function of attention in all age groups, compared with the indicators of the average population of group and children with an increased background of anxiety. Children with an increased background of anxiety have a tendency to prevalence and excessive spatial synchronization of the alpha rhythm. ln healthy children, the fact of a decrease in wakefulness and the presence of signs of anxiety in the clinic and in EEG patterns indicates individual personalities and should not be considered as pathology.


Author(s):  
Khuan Seow ◽  
Nadia Caidi

Canada has an aging population with the fastest growing age groups (80 and 45-64 years old) vulnerable to age-related diseases such as Alzheimer’s disease. Caregiving responsibilities often fall to the family members of the afflicted without much attention and consideration being placed on the information needs of these caregivers. We call for a better understanding of these caregivers' information needs and uses by social policy makers as well as information providers.La population du Canada a tendance à vieillir considérablement, avec la hausse la plus rapide dans les groupes d’âge (80 et 45 à 64 ans). Les personnes âges sont très vulnérables à toute sorte de maladies, telles que la maladie d’Alzheimer. La responsabilité revient souvent aux membres de la famille qui doivent prendre soin des personnes atteintes de cette maladie. Or, nous ne connaissons que peu de chose sur les besoins en information des personnes qui prennent soin de ces malades de l’Alzheimer : qui sont-ils ? Quelles sont leurs sources... 


2018 ◽  
Author(s):  
Foyzul Rahman ◽  
Sabrina Javed ◽  
Ian Apperly ◽  
Peter Hansen ◽  
Carol Holland ◽  
...  

Age-related decline in Theory of Mind (ToM) may be due to waning executive control, which is necessary for resolving conflict when reasoning about others’ mental states. We assessed how older (OA; n=50) versus younger adults (YA; n=50) were affected by three theoretically relevant sources of conflict within ToM: competing Self-Other perspectives; competing cued locations and outcome knowledge. We examined which best accounted for age-related difficulty with ToM. Our data show unexpected similarity between age groups when representing a belief incongruent with one’s own. Individual differences in attention and motor response speed best explained the degree of conflict experienced through conflicting Self-Other perspectives. However, OAs were disproportionately affected by managing conflict between cued locations. Age and spatial working memory were most relevant for predicting the magnitude of conflict elicited by conflicting cued locations. We suggest that previous studies may have underestimated OA’s ToM proficiency by including unnecessary conflict in ToM tasks.


Author(s):  
L. Yu. Orekhova ◽  
A. A. Petrov ◽  
E. S. Loboda ◽  
I. V. Berezkina ◽  
K. V. Shadrina

Relevance. The study of age-related features of microcirculation in periodontal tissues, using non-invasive functional research methods, allows us to develop the optimal range of therapeutic measures, as well as form a “personalized therapeutic case”.Purpose. Study of the functional state of the microvasculature in the tissues of the parodont in individuals of various age groups.Materials and methods. A standard dental examination of 80 patients was carried out, the sample of participants was ranked in 4 groups by age: 1 group – 12 years old, 2 group – 15 years old, 3 group – from 16 to 18 years old, 4 group – from 22 to 24 years old. Hygiene and periodontal indices were determined for all patients, such as papillarymarginal-alveolar (PMA) in the Parma modification, the Mulleman bleeding index in the Cowell modification (SBI), and the simplified Green Vermillion index of oral hygiene (OHI–s), caries intensity indicators for a permanent bite (CPI), as well as ultrasound dopplerography of periodontal tissues using the apparatus "Minimax-Doppler-K".Results. When studying microcirculation in periodontal tissues, distinctive characteristics of linear (Vas) and volumetric (Qas) blood flow rates, as well as indicators of pulsation indices (PI) and peripheral resistance (RI) in people of different age groups were recorded.Conclusions. This study confirms the presence of various hemodynamic indicators of periodontal tissues in the studied groups, which is due to structural features of the circulatory system in age periods.


2020 ◽  
Vol 17 (2) ◽  
pp. 187-192
Author(s):  
E.A. Novikova ◽  
◽  
O.V. Kostromina ◽  
D.V. Mikhailov ◽  
S.L. Leontiev ◽  
...  

Aim. The aim of the study was to determine the presence of peculiarities of the age structure in patients with various surrogate molecular biological subtypes of breast cancer. Materials and research methods. This work analyzes the age-related characteristics of the occurrence of molecular biological subtypes in 499 patients with invasive breast cancer. All cases were divided into 5 molecular biological subtypes based on immunohistochemical studies of hormone receptors, Her2, Ki-67. The average age of the patients was 53.4±0.39 years, the predominant group was patients from 50 to 60 years (37.2% of the total). Research results. In patients under 40 years old, the triple negative subtype prevailed (44.8%). Luminal A subtype prevailed in the groups 51-60 years old (more than 41.4%) and over 60 years old (39.7%). Luminal B (Her2-) subtype was equally found in all age groups.


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