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1.
Sensors (Basel) ; 24(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39065825

RESUMO

In this paper, we present the design of a millimeter-wave 1 × 4 linear MIMO array antenna that operates across multiple resonance frequency bands: 26.28-27.36 GHz, 27.94-28.62 GHz, 32.33-33.08 GHz, and 37.59-39.47 GHz, for mm-wave wearable biomedical telemetry application. The antenna is printed on a flexible substrate with dimensions of 11.0 × 44.0 mm2. Each MIMO antenna element features a modified slot-loaded triangular patch, incorporating 'cross'-shaped slots in the ground plane to improve impedance matching. The MIMO antenna demonstrates peak gains of 6.12, 8.06, 5.58, and 8.58 dBi at the four resonance frequencies, along with a total radiation efficiency exceeding 75%. The proposed antenna demonstrates excellent diversity metrics, with an ECC < 0.02, DG > 9.97 dB, and CCL below 0.31 bits/sec/Hz, indicating high performance for mm-wave applications. To verify its properties under flexible conditions, a bending analysis was conducted, showing stable S-parameter results with deformation radii of 40 mm (Rx) and 25 mm (Ry). SAR values for the MIMO antenna are calculated at 28.0/38.0 GHz. The average SAR values for 1 gm/10 gm of tissues at 28.0 GHz are found to be 0.0125/0.0079 W/Kg, whereas, at 38.0 GHz, average SAR values are 0.0189/0.0094 W/Kg, respectively. Additionally, to demonstrate the telemetry range of biomedical applications, a link budget analysis at both 28.0 GHz and 38.0 GHz frequencies indicated strong signal strength of 33.69 dB up to 70 m. The fabricated linear MIMO antenna effectively covers the mm-wave 5G spectrum and is suitable for wearable and biomedical applications due to its flexible characteristics.


Assuntos
Telemetria , Dispositivos Eletrônicos Vestíveis , Telemetria/instrumentação , Telemetria/métodos , Humanos , Tecnologia sem Fio/instrumentação , Desenho de Equipamento
2.
J Vis Exp ; (208)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949379

RESUMO

The use of telemetry techniques to better understand the behavior and survival of juvenile American shad (Alosa sapidissima), as they migrate through hydropower systems, has been challenging because shad are widely known to be particularly sensitive to handling. The goal of this study was to develop a tagging protocol using a new, acoustic micro transmitter that minimizes the detrimental effects of the tagging process and maximizes post-tagging survival of juvenile American shad. Limiting out-of-water handling and the use of brackish saltwater (7.5 parts per thousand) before and after tagging improved survival for shad tagged using a simple pectoral implantation method. This protocol provides a detailed, step-by-step procedure for tagging juvenile shad with acoustic transmitters. Fish tagged using this procedure and held in the laboratory for 60 days had an 81.5% survival rate, compared to 70% for their untagged counterparts. The successful tagging and handling practices developed in this study could be applied to field telemetry studies of juvenile shad and other sensitive species.


Assuntos
Acústica , Telemetria , Animais , Acústica/instrumentação , Telemetria/métodos , Telemetria/instrumentação , Sistemas de Identificação Animal/métodos , Sistemas de Identificação Animal/instrumentação
3.
An Acad Bras Cienc ; 96(suppl 1): e20231019, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39082590

RESUMO

Many aspects of the ecology, evolution and social behavior of wild-living primates remain un-explored and require further investigation. While long-term field studies are crucial for addressing conservation concerns for many primates' species, acquiring the necessary data is often challenging, often due to difficulties in locating study groups. Radio-telemetry has significantly facilitated the study of primates and other animals living in tropical forests. However, there are important practical challenges in the process of capturing and releasing animals after placement of telemetry collars. In this study, we report guidelines and considerations for capturing and collaring wild capuchin monkeys, Sapajus nigritus cucullatus, in the Atlantic Forest of Argentina. Our ultimate goal is to contribute to making captures safer, preventing harm and stress to animals when using radio-telemetry in monitoring strategies for conservation of this primate species. These methods can be useful for researchers using field capture and radio-telemetry for monitoring groups or populations of wild primates, specifically wild Sapajus.


Assuntos
Telemetria , Animais , Telemetria/métodos , Argentina , Sapajus , Conservação dos Recursos Naturais/métodos , Animais Selvagens
4.
J Pharmacol Toxicol Methods ; 128: 107537, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38955286

RESUMO

Our study retrospectively examines 51 non-rodent general toxicology studies conducted over the past 8 years to ascertain the influence of recording methodologies on baseline cardiovascular (CV) parameters and statistical sensitivity. Specifically, our work aims to evaluate the frequency of cardiovascular parameter recording categorized by therapeutic modality and study type, to assess the variability in these parameters based on measurement techniques, and to determine the sample sizes needed for detecting relevant changes in heart rate (HR), blood pressure (BP), and QTc interval in non-human primate (NHP) studies. Results indicate that electrocardiogram (ECG) measurements in dogs and NHP were recorded in 63% of studies, combined with BP recording in 18% of studies, while BP was never recorded alone. Trend analysis reveals a decline in the utilisation of restraint-based methods for ECG measurements post-2017, to the benefit of telemetry-based recordings, particularly Jacketed External Telemetry (JET). There was a marked difference in baseline values, with restraint-based methods showing significantly higher HR and QTc values compared to JET, likely linked to animal stress. Further analysis suggests an unrealistic and unethical sample size requirement in NHP studies for detecting biologically meaningful CV parameter changes using restraint-based methods, while JET methods necessitate significantly smaller sample sizes. This retrospective study indicates a notable shift from snapshots short-duration, restraint-based methods towards telemetry approaches over the recent years, especially with an increased usage of implanted telemetry. The transition contributes to potential consensus within industry or regulatory frameworks for optimal practices in assessing ECG, HR, and BP in general toxicology studies.


Assuntos
Pressão Sanguínea , Eletrocardiografia , Frequência Cardíaca , Telemetria , Animais , Estudos Retrospectivos , Eletrocardiografia/métodos , Cães , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Telemetria/métodos , Testes de Toxicidade/métodos , Determinação da Pressão Arterial/métodos
5.
J Neurosci Methods ; 409: 110217, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38964477

RESUMO

BACKGROUND: Parkinson's patients have significant autonomic dysfunction, early detect the disorder is a major challenge. To assess the autonomic function in the rat model of rotenone induced Parkinson's disease (PD), Blood pressure and ECG signal acquisition are very important. NEW METHOD: We used telemetry to record the electrocardiogram and blood pressure signals from awake rats, with linear and nonlinear analysis techniques calculate the heart rate variability (HRV) and blood pressure variability (BPV). we applied nonlinear analysis methods like sample entropy and detrended fluctuation analysis to analyze blood pressure signals. Particularly, this is the first attempt to apply nonlinear analysis to the blood pressure evaluate in rotenone induced PD model rat. RESULTS: HRV in the time and frequency domains indicated sympathetic-parasympathetic imbalance in PD model rats. Linear BPV analysis didn't reflect changes in vascular function and blood pressure regulation in PD model rats. Nonlinear analysis revealed differences in BPV, with lower sample entropy results and increased detrended fluctuation analysis results in the PD group rats. COMPARISON WITH EXISTING METHODS AND CONCLUSIONS: our experiments demonstrate the ability to evaluate autonomic dysfunction in models of Parkinson's disease by combining the analysis of BPV with HRV, consistent with autonomic impairment in PD patients. Nonlinear analysis by blood pressure signal may help in early detection of the PD. It indicates that the fluctuation of blood pressure in the rats in the rotenone model group tends to be regular and predictable, contributes to understand the PD pathophysiological mechanisms and to find strategies for early diagnosis.


Assuntos
Sistema Nervoso Autônomo , Pressão Sanguínea , Modelos Animais de Doenças , Eletrocardiografia , Frequência Cardíaca , Rotenona , Animais , Rotenona/toxicidade , Frequência Cardíaca/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Masculino , Sistema Nervoso Autônomo/fisiopatologia , Sistema Nervoso Autônomo/efeitos dos fármacos , Telemetria/métodos , Dinâmica não Linear , Ratos , Transtornos Parkinsonianos/fisiopatologia , Transtornos Parkinsonianos/induzido quimicamente , Ratos Sprague-Dawley , Doença de Parkinson/fisiopatologia
6.
Health Informatics J ; 30(2): 14604582241262251, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865081

RESUMO

OBJECTIVE: Family health history (FHx) is an important tool in assessing one's risk towards specific health conditions. However, user experience of FHx collection tools is rarely studied. ItRunsInMyFamily.com (ItRuns) was developed to assess FHx and hereditary cancer risk. This study reports a quantitative user experience analysis of ItRuns. METHODS: We conducted a public health campaign in November 2019 to promote FHx collection using ItRuns. We used software telemetry to quantify abandonment and time spent on ItRuns to identify user behaviors and potential areas of improvement. RESULTS: Of 11,065 users who started the ItRuns assessment, 4305 (38.91%) reached the final step to receive recommendations about hereditary cancer risk. Highest abandonment rates were during Introduction (32.82%), Invite Friends (29.03%), and Family Cancer History (12.03%) subflows. Median time to complete the assessment was 636 s. Users spent the highest median time on Proband Cancer History (124.00 s) and Family Cancer History (119.00 s) subflows. Search list questions took the longest to complete (median 19.50 s), followed by free text email input (15.00 s). CONCLUSION: Knowledge of objective user behaviors at a large scale and factors impacting optimal user experience will help enhance the ItRuns workflow and improve future FHx collection.


Assuntos
Anamnese , Humanos , Anamnese/métodos , Anamnese/estatística & dados numéricos , Saúde da Família , Feminino , Masculino , Telemetria/métodos , Software
7.
Sci Rep ; 14(1): 14628, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918536

RESUMO

Advances in tagging technologies are expanding opportunities to estimate survival of fish and wildlife populations. Yet, capture and handling effects could impact survival outcomes and bias inference about natural mortality processes. We developed a multistage time-to-event model that can partition the survival process into sequential phases that reflect the tagged animal experience, including handling and release mortality, post-release recovery mortality, and subsequently, natural mortality. We demonstrate performance of multistage survival models through simulation testing and through fish and bird telemetry case studies. Models are implemented in a Bayesian framework and can accommodate left, right, and interval censorship events. Our results indicate that accurate survival estimates can be achieved with reasonable sample sizes ( n ≈ 100 + ) and that multimodel inference can inform hypotheses about the configuration and length of survival stages needed to adequately describe mortality processes for tracked specimens. While we focus on survival estimation for tagged fish and wildlife populations, multistage time-to-event models could be used to understand other phenomena of interest such as migration, reproduction, or disease events across a range of taxa including plants and insects.


Assuntos
Teorema de Bayes , Peixes , Animais , Peixes/fisiologia , Aves/fisiologia , Animais Selvagens , Telemetria/métodos
8.
J Neural Eng ; 21(3)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38861967

RESUMO

Objective. We intend to chronically restore somatosensation and provide high-fidelity myoelectric control for those with limb loss via a novel, distributed, high-channel-count, implanted system.Approach.We have developed the implanted Somatosensory Electrical Neurostimulation and Sensing (iSens®) system to support peripheral nerve stimulation through up to 64, 96, or 128 electrode contacts with myoelectric recording from 16, 8, or 0 bipolar sites, respectively. The rechargeable central device has Bluetooth® wireless telemetry to communicate to external devices and wired connections for up to four implanted satellite stimulation or recording devices. We characterized the stimulation, recording, battery runtime, and wireless performance and completed safety testing to support its use in human trials.Results.The stimulator operates as expected across a range of parameters and can schedule multiple asynchronous, interleaved pulse trains subject to total charge delivery limits. Recorded signals in saline show negligible stimulus artifact when 10 cm from a 1 mA stimulating source. The wireless telemetry range exceeds 1 m (direction and orientation dependent) in a saline torso phantom. The bandwidth supports 100 Hz bidirectional update rates of stimulation commands and data features or streaming select full bandwidth myoelectric signals. Preliminary first-in-human data validates the bench testing result.Significance.We developed, tested, and clinically implemented an advanced, modular, fully implanted peripheral stimulation and sensing system for somatosensory restoration and myoelectric control. The modularity in electrode type and number, including distributed sensing and stimulation, supports a wide variety of applications; iSens® is a flexible platform to bring peripheral neuromodulation applications to clinical reality. ClinicalTrials.gov ID NCT04430218.


Assuntos
Eletromiografia , Humanos , Eletromiografia/métodos , Eletrodos Implantados , Tecnologia sem Fio/instrumentação , Telemetria/instrumentação , Telemetria/métodos , Desenho de Equipamento/métodos , Músculo Esquelético/fisiologia , Músculo Esquelético/inervação
9.
Sci Rep ; 14(1): 13180, 2024 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-38849378

RESUMO

The movement ecology of European seabass, Dicentrarchus labrax, remains poorly understood, especially in the northern ranges of its distribution. To investigate migration patterns of seabass from the southern North Sea, we combined data from different projects from four countries using various tagging techniques. This resulted in 146 recaptures (out of 5598 externally marked seabass), 138 detected animals (out of 162 seabass fitted with an acoustic transmitter) and 76 archived depth and temperature series (out of 323 seabass with an archival tag). Using geolocation modelling, we distinguished different migration strategies, whereby individual fish migrated to the eastern English Channel (15.1%), the western English Channel (28.3%), the Celtic Sea and the norther part of the Bay of Biscay (17.0%), or stayed in the North Sea (39.6%). A high number of seabass exhibited fidelity to the North Sea (90.5% of recaptures, 55.3% for acoustic transmitters and 44.7% of archival tags). Although seabass are generally considered to migrate southwards in winter, a large number of individuals (n = 62) were observed in the southern North Sea, where spawning might potentially occur in a particular deep location along the coast of Norfolk in the UK. Our results highlight the need to consider fine-scaled population structuring in fisheries assessment, and indicate that current seasonal fisheries closures are not aligned with the ecology of seabass in the North Sea.


Assuntos
Acústica , Migração Animal , Bass , Telemetria , Animais , Mar do Norte , Migração Animal/fisiologia , Bass/fisiologia , Telemetria/métodos , Estações do Ano
10.
Sensors (Basel) ; 24(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38931520

RESUMO

With the escalation in the size and complexity of modern Denial of Service attacks, there is a need for research in the context of Machine Learning (ML) used in attack execution and defense against such attacks. This paper investigates the potential use of ML in generating behavioral telemetry data using Long Short-Term Memory network and spoofing requests for the analyzed traffic to look legitimate. For this research, a custom testing environment was built that listens for mouse and keyboard events and analyzes them accordingly. While the economic feasibility of this attack currently limits its immediate threat, advancements in technology could make it more cost-effective for attackers in the future. Therefore, proactive development of countermeasures remains essential to mitigate potential risks and stay ahead of evolving attack methods.


Assuntos
Segurança Computacional , Aprendizado de Máquina , Memória de Curto Prazo/fisiologia , Humanos , Telemetria/métodos , Redes de Comunicação de Computadores , Algoritmos
11.
J Pharmacol Toxicol Methods ; 128: 107525, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38851600

RESUMO

INTRODUCTION: Nonclinical evaluation of the cardiovascular effects of novel chemical or biological entities (NCE, NBEs) is crucial for supporting first-in-human clinical trials. One important aspect of these evaluations is the assessment of potential QT/QTc prolongation risk, as drug-induced QT prolongation can have catastrophic effects. The recent publication of E14/S7B Q&As allows for the situational incorporation of nonclinical QTc data as part of an integrated risk assessment for a Thorough QT (TQT) waiver application provided certain best practice criteria are met. Recent publications provided detailed characterization of nonclinical QTc telemetry data collected from the commonly used Latin square study design. METHODS: To understand whether data from alternate telemetry study designs were sufficient to serve as part of the E14/S7B integrated risk assessment, we report the performance and translational sensitivity to identify clinical risk of QTc prolongation risk for an ascending dose telemetry design. RESULTS: The data demonstrated low variability in QTci interval within animals from day to day, indicating a well-controlled study environment and limited concern for uncontrolled effects across dosing days. Historical study variances of the ascending dose design with n = 4 subjects, measured by least significant difference (LSD) and root mean square error (RMSE) values, were low enough to detect a + 10 ms QTci interval change, and the median minimum detectable difference (MDD) for QTci interval changes was <10 ms. Furthermore, concentration-QTci (C-QTci) assessments to determine +10 ms QTci increases for known hERG inhibitors were comparable to clinical CC values listed in the E14/S7B training materials, supporting the use of the ascending dose design in an E14/S7B integrated risk assessment. DISCUSSION: These findings suggest that the ascending dose design can be a valuable tool in nonclinical evaluation of QT/QTc prolongation risk and the support of TQT waiver applications.


Assuntos
Relação Dose-Resposta a Droga , Eletrocardiografia , Síndrome do QT Longo , Telemetria , Animais , Telemetria/métodos , Medição de Risco/métodos , Síndrome do QT Longo/induzido quimicamente , Cães , Eletrocardiografia/métodos , Eletrocardiografia/efeitos dos fármacos , Masculino , Avaliação Pré-Clínica de Medicamentos/métodos , Frequência Cardíaca/efeitos dos fármacos , Feminino
12.
J Pharmacol Toxicol Methods ; 128: 107528, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38852684

RESUMO

INTRODUCTION: In preclinical cardiovascular safety pharmacology studies, statistical analysis of the rate corrected QT interval (QTc) is the focus for predicting QTc interval changes in the clinic. Modeling of a concentration/QTc relationship, common clinically, is limited due to minimal pharmacokinetic (PK) data in nonclinical testing. It is possible, however, to relate the average drug plasma concentration from sparse PK samples over specific times to the mean corrected QTc. We hypothesize that averaging drug plasma concentration and the QTc-rate relationship over time provides a simple, accurate concentration-QTc relationship bridging statistical and concentration/QTc modeling. METHODS: Cardiovascular telemetry studies were conducted in non-human primates (NHP; n = 48) and canines (n = 8). Pharmacokinetic samples were collected on separate study days in both species. Average plasma concentrations for specific intervals (CAverage0-X) were calculated for moxifloxacin in canines and NHP using times corresponding to super-intervals for the QTc data statistical analysis. The QTc effect was calculated for each super-interval using a linear regression correction incorporating QT and HR data from the whole super-interval. The concentration QTc effects were then modeled. RESULTS: In NHP, a 10.9 ± 0.06 ms (mean ± 95% CI) change in QTc was detected at approximately 1.5× the moxifloxacin plasma concentration that causes a 10 ms QTc change in humans, based on a 0-24 h super-interval. When simulating a drug without QT effects, mock, no effect on QTc was detected at up to 3× the clinical concentration. Similarly, in canines, a 16.6 ± 0.1 ms change was detected at 1.7× critical clinical moxifloxacin concentration, and a 0.04 ± 0.1 ms change was seen for mock. CONCLUSIONS: While simultaneous PK and QTc data points are preferred, practical constraints and the need for QTc averaging did not prevent concentration-QTc analyses. Utilizing a 0-24 h super-interval method illustrates a simple and effective method to address cardiovascular questions when preclinical drug exposures exceed clinical concentrations.


Assuntos
Eletrocardiografia , Síndrome do QT Longo , Moxifloxacina , Telemetria , Animais , Cães , Moxifloxacina/farmacocinética , Moxifloxacina/administração & dosagem , Eletrocardiografia/efeitos dos fármacos , Eletrocardiografia/métodos , Telemetria/métodos , Síndrome do QT Longo/induzido quimicamente , Avaliação Pré-Clínica de Medicamentos/métodos , Fluoroquinolonas/farmacocinética , Fluoroquinolonas/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Masculino , Modelos Animais , Relação Dose-Resposta a Droga , Feminino
13.
J Pharmacol Toxicol Methods ; 127: 107517, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38797367

RESUMO

INTRODUCTION: Rat telemetry is the assay of choice to assess the potential effects of novel drug candidates on cardiovascular parameters during early drug discovery. Telemetry device implantation can be combined with venous catheter and access button implantation when intravenous administration of the drug substance is required. METHODS: Rats (Sprague Dawley or Han Wistar) were implanted with telemetry devices for arterial blood pressure measurement using either direct aortic catheterisation (n = 131) or aortic catheterisation via the femoral artery (n = 17). Bipolar leads for ECG recording were also implanted in some of the animals (n = 102). Femoral vein catheters and access buttons were implanted as a separate surgery after the initial telemetry implantation (n = 43). RESULTS: 128 animals (86%) were implanted successfully with telemetry devices without any notable surgical or post-surgical problems. When considering the 2 different catheterisation methods separately, the success rate of the direct aortic approach was 88% compared to 76% with the aortic placement via the femoral artery. Lameness was the most common post-surgical problem. Blood loss during surgery and ischaemic patches on the tail were also observed at a low incidence with the direct aortic approach. Catheter pull-out occurred in some rats before the first signal check reducing the overall success rate for blood pressure measurement using the direct aortic approach to 85%. A 95% success rate was observed for catheter and access button implantation. DISCUSSION: A high success rate is possible when implanting telemetry devices in rats with and without venous catheters and access buttons. We have attempted to provide solutions to problems and describe refinements to the procedure which may further improve surgical outcomes.


Assuntos
Ratos Sprague-Dawley , Ratos Wistar , Telemetria , Animais , Telemetria/métodos , Telemetria/instrumentação , Ratos , Masculino , Artéria Femoral/cirurgia , Pressão Sanguínea/efeitos dos fármacos , Eletrocardiografia/métodos , Avaliação Pré-Clínica de Medicamentos/métodos
14.
Clin Pharmacol Ther ; 116(1): 106-116, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38709223

RESUMO

The ICH E14/S7B Q&As highlighted the need for best practices concerning the design, execution, analysis, interpretation, and reporting of the in vivo non-rodent QT assay as a component of the integrated risk assessment to potentially support a TQT waiver or substitute. We conducted a dog telemetry study to assess the effects on QTc of six reference compounds (five positive and one negative) previously evaluated by Darpo et al. (2015) in humans. The sensitivity of the assay to detect QTc increases was determined, and exposure-response analysis was performed, as done in clinical practice. By-timepoint analysis showed QTc prolongation induced by moxifloxacin, dofetilide, dolasetron, ondansetron, and quinine within human relevant plasma exposures ranges. Moreover, a hysteresis was observed for quinine. As expected, levocetirizine showed no statistically significant effect on QTc across a range of exposure, well exceeding the therapeutic Cmax. Power analyses confirmed the study ability to detect statistically significant QTc changes of less than 10 milliseconds with 80% probability, even with a sample size as low as n = 4 animals. Finally, concentration-QTc modeling enabled to predict the minimal plasma concentration needed to detect a 10 milliseconds QTc prolongation, including for quinine. The comparison with clinical available data supported the relevance of dogs under these experimental conditions as a robust translational predictor of drug-induced QTc prolongation in humans as a key pillar of the integrated risk assessment.


Assuntos
Eletrocardiografia , Síndrome do QT Longo , Cães , Animais , Estudos Prospectivos , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/diagnóstico , Eletrocardiografia/efeitos dos fármacos , Masculino , Feminino , Telemetria/métodos , Medição de Risco/métodos , Humanos , Frequência Cardíaca/efeitos dos fármacos
15.
J Pharmacol Toxicol Methods ; 127: 107510, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38705245

RESUMO

Cardiovascular safety pharmacology and toxicology studies include vehicle control animals in most studies. Electrocardiogram data on common vehicles is accumulated relatively quickly. In the interests of the 3Rs principles it may be useful to use this historical information to reduce the use of animals or to refine the sensitivity of studies. We used implanted telemetry data from a large nonhuman primate (NHP) cardiovascular study (n = 48) evaluating the effect of moxifloxacin. We extracted 24 animals to conduct a n = 3/sex/group analysis. The remaining 24 animals were used to generate 1000 unique combinations of 3 male and 3 female NHP to act as control groups for the three treated groups in the n = 3/sex/group analysis. The distribution of treatment effects, median minimum detectable difference (MDD) values were gathered from the 1000 studies. These represent contemporary controls. Data were available from 42 NHP from 3 other studies in the same laboratory using the same technology. These were used to generate 1000 unique combinations of 6, 12, 18, 24 and 36 NHP to act as historical control animals for the 18 animals in the treated groups of the moxifloxacin study. Data from an additional laboratory were also available for 20 NHP. The QT, RR and QT-RR data from the three sources were comparable. However, differences in the time course of QTc effect in the vehicle data from the two laboratories meant that it was not possible to use cross-lab controls. In the case of historical controls from the same laboratory, these could be used in place of the contemporary controls in determining a treatment's effect. There appeared to be an advantage in using larger (≥18) group sizes for historical controls. These data support the opportunity of using historical controls to reduce the number of animals used in new cardiovascular studies.


Assuntos
Eletrocardiografia , Fluoroquinolonas , Moxifloxacina , Telemetria , Animais , Feminino , Eletrocardiografia/métodos , Eletrocardiografia/efeitos dos fármacos , Masculino , Telemetria/métodos , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/fisiopatologia , Grupos Controle , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Estado de Consciência/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos
16.
J Pharmacol Toxicol Methods ; 127: 107512, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38719163

RESUMO

The principle of proportionality of the systolic area of the central aortic pressure to stroke volume (SV) has been long known. The aim of the present work was to evaluate an in silico solution derived from this principle for modelling SV (iSV model) in cardiovascular safety pharmacology studies by telemetry. Blood pressure was measured in the abdominal aorta in accordance with standard practice. Central aortic pressure was modelled from the abdominal aortic pressure waveform using the N-point moving average (NPMA) method for beat-to-beat estimation of SV. First, the iSV was compared to the SV measured by ultrasonic flowmetry in the ascending aorta (uSV) after various pharmacological challenges in beagle dogs anaesthetised with etomidate/fentanyl. The iSV showed minimal bias (0.2 mL i.e. 2%) and excellent agreement with uSV. Then, previous telemetry studies including reference vasoactive and inotropic compounds were retrospectively reanalysed to model drug effects on stroke volume (iSV), cardiac output (iCO) and systemic vascular resistance (iSVR). Among them, the examples of nicardipine and isoprenaline highlight risks of erroneous or biased estimation of drug effects from the abdominal aortic pressure due to pulse pressure amplification. Furthermore, the examples of verapamil, quinidine and moxifloxacin show that iSV, iCO and iSVR are earlier biomarkers than blood pressure itself for predicting drug effect on blood pressure. This in silico modelling approach included in vivo telemetry safety pharmacology studies can be considered as a New Approach Methodology (NAM) that provides valuable additional information and contribute to improving non-clinical translational research to the clinic.


Assuntos
Débito Cardíaco , Simulação por Computador , Volume Sistólico , Telemetria , Resistência Vascular , Animais , Cães , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/fisiologia , Resistência Vascular/efeitos dos fármacos , Telemetria/métodos , Débito Cardíaco/efeitos dos fármacos , Débito Cardíaco/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Masculino
17.
Childs Nerv Syst ; 40(8): 2391-2399, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38587626

RESUMO

PURPOSE: Telemetric monitoring of intracranial pressure (ICP) facilitates long-term measurements and home monitoring, thus potentially reducing diagnostic imaging and acute hospital admissions in favour of outpatient appointments. Especially in paediatric patients, telemetric ICP monitoring requires a high level of collaboration and compliance from patients and parents. In this study, we aim to systematically investigate (1) patient and parent perception of telemetric ICP system utility and (2) hospital contact history and thus the potential cost-benefit of telemetric ICP monitoring in paediatric patients with a cerebrospinal fluid disorder. METHODS: We conducted a nationwide questionnaire study, including paediatric patients with either a current or previous telemetric ICP sensor and their parents. Additionally, a retrospective review of electronic health records for all included children was performed. RESULTS: We included 16 children (age range 3-16 years), with a total of 41 telemetric ICP sensors implanted. Following sensor implantation, the frequency of telephone contacts and outpatient visits increased. No corresponding decrease in hospital admissions or total length of stay was found. The telemetric ICP sensor provided most parents with an improved sense of security and was seen as a necessary and valuable tool in treatment guidance. The size and shape of the sensor itself were reported as disadvantages, while the external monitoring equipment was reported as easy to use but too large and heavy for a child to carry. CONCLUSION: Though, in quantitative terms, there was no cost-benefit of the telemetric ICP sensor, it contributed to extended parental involvement and a sense of improved safety.


Assuntos
Pressão Intracraniana , Telemetria , Humanos , Criança , Adolescente , Feminino , Masculino , Pré-Escolar , Pressão Intracraniana/fisiologia , Inquéritos e Questionários , Telemetria/métodos , Estudos Retrospectivos , Monitorização Fisiológica/métodos , Monitorização Fisiológica/instrumentação , Pais
18.
Lab Anim (NY) ; 53(5): 117-120, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38637688

RESUMO

Many research groups explore the regulation of hibernation or compare the physiology of heterothermic mammals between the torpid and aroused, euthermic states. Current methods for monitoring torpor (for example, infrared cameras, body temperature or heart-rate telemetry, and motion sensing) are costly, require specialized techniques, and can be invasive. Here we present an alternate method for determining torpor-bout duration that is cost-effective, noninvasive and accurate: paper towel shredding. In the winter, euthermic thirteen-lined ground squirrels will shred paper towels placed in the cage, but torpid animals will not. The presence of a shredded paper towel, indicating an arousal from torpor, is easily evaluated during routine daily monitoring. In 12 animals over 52 days, this simple technique detected 59 arousals with 100% accuracy when compared with the body temperature telemetry of the same animals. Moreover, this novel method avoids some of the drawbacks of other cheap monitoring systems such as the sawdust technique.


Assuntos
Hibernação , Sciuridae , Animais , Sciuridae/fisiologia , Hibernação/fisiologia , Nível de Alerta/fisiologia , Telemetria/métodos , Telemetria/veterinária , Temperatura Corporal , Masculino , Papel , Abrigo para Animais
19.
J Vis Exp ; (206)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38647323

RESUMO

Changes in the mother-offspring relationship are presumably accompanied by dynamic changes in the autonomic nervous system. Although temporal measurements of autonomic activity have been performed in human mothers and infants, the analysis of long-term changes remains unexplored. Mouse mothers can form social bonds with their pups and have a short period of pregnancy and lactation, which makes them useful for the examination of physiological changes from pregnancy to pup-rearing. Therefore, a telemetry system was used for several weeks to measure the changes in the autonomic nervous system and the behavior of mouse mothers. The current results showed that an electrocardiogram (ECG) could be stably recorded regardless of the movements of mothers and parturition. ECG analysis showed that the heart rate gradually decreased from pregnancy to lactation, and sympathetic activity sharply increased as the pups developed. Furthermore, the simultaneous recording of behavior and ECG in the home cage enabled us to understand the behavior-dependent influences on the ECG, thereby revealing the characteristics of autonomic nervous activity during each behavior. Thus, the present experimental method helps to understand how the physiological characteristics of mothers change from pregnancy through pup rearing, supporting the healthy development of pups.


Assuntos
Comportamento Animal , Eletrocardiografia , Lactação , Animais , Feminino , Gravidez , Camundongos , Lactação/fisiologia , Eletrocardiografia/métodos , Comportamento Animal/fisiologia , Sistema Nervoso Autônomo/fisiologia , Frequência Cardíaca/fisiologia , Telemetria/métodos
20.
J Comp Eff Res ; 13(6): e240008, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38602503

RESUMO

Aim: Patients with ischemic stroke (IS) commonly undergo monitoring to identify atrial fibrillation with mobile cardiac outpatient telemetry (MCOT) or implantable loop recorders (ILRs). The authors compared readmission, healthcare cost and survival in patients monitored post-stroke with either MCOT or ILR. Materials & methods: The authors used claims data from Optum's de-identified Clinformatics® Data Mart Database to identify patients with IS hospitalized from January 2017 to December 2020 who were prescribed ambulatory cardiac monitoring via MCOT or ILR. They compared the costs associated with the initial inpatient visit as well as the rate and causes of readmission, survival and healthcare costs over the following 18 months. Datasets were balanced using patient baseline and hospitalization characteristics. Multivariable generalized linear gamma regression was used for cost comparisons. Cox proportional hazard regression was used for survival and readmission analysis. Sub-cohorts were analyzed based on the severity of the index IS. Results: In 2244 patients, readmissions were significantly lower in the MCOT monitored group (30.2%) compared with the ILR group (35.4%) (hazard ratio [HR] 1.23; 95% CI: 1.04-1.46). Average cost over 18 months starting with the index IS was $27,429 (USD) lower in the MCOT group (95% CI: $22,353-$32,633). Survival difference bordered on statistical significance and trended to lower mortality in MCOT (8.9%) versus ILR (11.3%) (HR 1.30; 95% CI: 1:00-1.69), led by significance in patients with complications or comorbidities with the index event (MCOT 7.5%, ILR 11.5%; HR 1.62; 95% CI: 1.11-2.36). Conclusion: The use of MCOT versus ILR as the primary monitor following IS was associated with significant decreases in readmission, lower costs for the initial IS and total care over the next 18 months, significantly lower mortality for patients with complications and comorbidities at the index stroke, and a trend toward improved survival across all patients.


Assuntos
Readmissão do Paciente , Telemetria , Humanos , Masculino , Feminino , Idoso , Telemetria/economia , Telemetria/métodos , Telemetria/instrumentação , Readmissão do Paciente/estatística & dados numéricos , Readmissão do Paciente/economia , Pessoa de Meia-Idade , Fibrilação Atrial/economia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/mortalidade , Custos de Cuidados de Saúde/estatística & dados numéricos , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/diagnóstico , AVC Isquêmico/economia , AVC Isquêmico/diagnóstico , AVC Isquêmico/mortalidade , Estudos Retrospectivos , Idoso de 80 Anos ou mais
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