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1.
Sensors (Basel) ; 24(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38276348

RESUMEN

Inertial measurement units (IMUs) provide exciting opportunities to collect large volumes of running biomechanics data in the real world. IMU signals may, however, be affected by variation in the initial IMU placement or movement of the IMU during use. To quantify the effect that changing an IMU's location has on running data, a reference IMU was 'correctly' placed on the shank, pelvis, or sacrum of 74 participants. A second IMU was 'misplaced' 0.05 m away, simulating a 'worst-case' misplacement or movement. Participants ran over-ground while data were simultaneously recorded from the reference and misplaced IMUs. Differences were captured as root mean square errors (RMSEs) and differences in the absolute peak magnitudes and timings. RMSEs were ≤1 g and ~1 rad/s for all axes and misplacement conditions while mean differences in the peak magnitude and timing reached up to 2.45 g, 2.48 rad/s, and 9.68 ms (depending on the axis and direction of misplacement). To quantify the downstream effects of these differences, initial and terminal contact times and vertical ground reaction forces were derived from both the reference and misplaced IMU. Mean differences reached up to -10.08 ms for contact times and 95.06 N for forces. Finally, the behavior in the frequency domain revealed high coherence between the reference and misplaced IMUs (particularly at frequencies ≤~10 Hz). All differences tended to be exaggerated when data were analyzed using a wearable coordinate system instead of a segment coordinate system. Overall, these results highlight the potential errors that IMU placement and movement can introduce to running biomechanics data.


Asunto(s)
Carrera , Humanos , Pierna , Fenómenos Biomecánicos , Movimiento , Pelvis , Marcha
2.
Sensors (Basel) ; 23(11)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37299749

RESUMEN

We evaluated 18 methods capable of identifying initial contact (IC) and terminal contact (TC) gait events during human running using data from a single wearable sensor on the shank or sacrum. We adapted or created code to automatically execute each method, then applied it to identify gait events from 74 runners across different foot strike angles, surfaces, and speeds. To quantify error, estimated gait events were compared to ground truth events from a time-synchronized force plate. Based on our findings, to identify gait events with a wearable on the shank, we recommend the Purcell or Fadillioglu method for IC (biases +17.4 and -24.3 ms; LOAs -96.8 to +131.6 and -137.0 to +88.4 ms) and the Purcell method for TC (bias +3.5 ms; LOAs -143.9 to +150.9 ms). To identify gait events with a wearable on the sacrum, we recommend the Auvinet or Reenalda method for IC (biases -30.4 and +29.0 ms; LOAs -149.2 to +88.5 and -83.3 to +141.3 ms) and the Auvinet method for TC (bias -2.8 ms; LOAs -152.7 to +147.2 ms). Finally, to identify the foot in contact with the ground when using a wearable on the sacrum, we recommend the Lee method (81.9% accuracy).


Asunto(s)
Carrera , Dispositivos Electrónicos Vestibles , Humanos , Fenómenos Biomecánicos , Marcha , Sacro , Acelerometría
3.
Sensors (Basel) ; 23(21)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37960420

RESUMEN

Twenty-seven methods of estimating vertical ground reaction force first peak, loading rate, second peak, average, and/or time series from a single wearable accelerometer worn on the shank or approximate center of mass during running were compared. Force estimation errors were quantified for 74 participants across different running surfaces, speeds, and foot strike angles and biases, repeatability coefficients, and limits of agreement were modeled with linear mixed effects to quantify the accuracy, reliability, and precision. Several methods accurately and reliably estimated the first peak and loading rate, however, none could do so precisely (the limits of agreement exceeded ±65% of target values). Thus, we do not recommend first peak or loading rate estimation from accelerometers with the methods currently available. In contrast, the second peak, average, and time series could all be estimated accurately, reliably, and precisely with several different methods. Of these, we recommend the 'Pogson' methods due to their accuracy, reliability, and precision as well as their stability across surfaces, speeds, and foot strike angles.


Asunto(s)
Marcha , Carrera , Humanos , Reproducibilidad de los Resultados , Fenómenos Biomecánicos , Aceleración
4.
AIDS Res Ther ; 17(1): 41, 2020 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-32660502

RESUMEN

BACKGROUND: In pregnancy, reduction of HIV plasma viral load (pVL) for the prevention of vertical transmission is time-constrained. The study primary objective is to investigate factors associated with faster initial HIV RNA half-life decay when combination antiretroviral treatment (cART) is initiated in pregnancy. METHODS: This was a multicentre, retrospective, observational study, conducted in south England, United Kingdom, between August 2001 and February 2018. Data were extracted from case notes of eligible women initiating cART during the index pregnancy. Anonymised data were collated and analysed centrally. Regression analyses were conducted to determine factors associated with faster HIV RNA half-life decay in the first 14 days after commencing cART (first-phase), and with achieving an undetectable maternal pVL by 36 weeks' gestation. We then assessed whether HIV- and obstetric- related parameters differed by antiretroviral third agent class and whether the proportions of women with undetectable pVL at 36 weeks' gestation and at delivery differed by antiretroviral third agent class. RESULTS: Baseline pVL was the only independent factor associated with faster first-phase HIV RNA half-life decay on commencing cART. Lower pVL on day 14 after starting cART was associated with an increased likelihood of achieving an undetectable pVL by 36 weeks' gestation. Integrase inhibitor-based cART was associated with a faster first-phase HIV RNA half-life decay on commencing cART. Overall, 73% and 85% of women had an undetectable pVL at 36 weeks' gestation and at delivery respectively, with no significant difference by antiretroviral third agent class. CONCLUSIONS: Only high baseline pVL independently contributed to a faster rate of first-phase viral half-life decay. pVL at 14 days after initiating cART allows early identification of treatment failure. In the first 14 days after initiating cART in pregnancy, integrase inhibitor-based cART reduced maternal pVL faster than protease inhibitor- and non-nucleoside reverse transcriptase-based cART. While our study findings support INSTI use when initiated in pregnancy especially when initiated at later gestations and in those with higher baseline pVL, other non-INSTI based cART with more data on safety in pregnancy also performed well.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Estabilidad del ARN , ARN Viral/metabolismo , Adulto , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/virología , Semivida , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Modelos Logísticos , Embarazo , ARN Viral/sangre , Estudios Retrospectivos , Reino Unido , Carga Viral/efectos de los fármacos
5.
J Antimicrob Chemother ; 72(6): 1760-1768, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28369381

RESUMEN

Objectives: Post-exposure prophylaxis (PEP) for HIV is often poorly tolerated and not completed. Alternative PEP regimens may improve adherence and completion, aiding HIV prevention. We conducted a randomized controlled trial of a maraviroc-based PEP regimen compared with a standard-of-care regimen using ritonavir-boosted lopinavir. Methods: Patients meeting criteria for PEP were randomized to tenofovir disoproxil/emtricitabine (200/245 mg) once daily plus ritonavir-boosted lopinavir (Kaletra ® 400/100 mg) or maraviroc 300 mg twice daily. The composite primary endpoint was completion of 28 days of the allocated PEP regimen without grade 3 or 4 clinical or laboratory adverse events (AEs) related to the PEP medication. Results: Two hundred and thirteen individuals were randomized (107 to maraviroc; 106 to Kaletra ® arm). Follow-up rates were high in both groups. There was no difference in the primary endpoint; 70 (71%) in the maraviroc and 64 (65%) in the Kaletra ® arm ( P = 0.36) completed PEP without grade 3 or 4 AEs. Discontinuation of PEP was the same (18%) in both groups. There were no grade 3 or 4 clinical AEs in either arm, but more grade 1 or 2 clinical AEs in the Kaletra ® arm (91% versus 70%; P < 0.001). Antidiarrhoeal medication use was higher in the Kaletra ® arm (67% versus 25%; P < 0.001). There were no HIV seroconversions in the study period. Conclusions: The completion rate in the absence of grade 3 or 4 AEs was similar with both regimens. Maraviroc-based PEP was better tolerated, supporting its use as an option for non-occupational PEP.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Ciclohexanos/uso terapéutico , Combinación Emtricitabina y Fumarato de Tenofovir Disoproxil/uso terapéutico , Infecciones por VIH/prevención & control , Lopinavir/uso terapéutico , Profilaxis Posexposición , Ritonavir/uso terapéutico , Triazoles/uso terapéutico , Adulto , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/efectos adversos , Recuento de Linfocito CD4 , Ciclohexanos/administración & dosificación , Ciclohexanos/efectos adversos , Combinación de Medicamentos , Combinación Emtricitabina y Fumarato de Tenofovir Disoproxil/administración & dosificación , Combinación Emtricitabina y Fumarato de Tenofovir Disoproxil/efectos adversos , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Inhibidores de la Proteasa del VIH/administración & dosificación , Inhibidores de la Proteasa del VIH/efectos adversos , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH-1/efectos de los fármacos , Humanos , Lopinavir/administración & dosificación , Lopinavir/efectos adversos , Masculino , Maraviroc , Cumplimiento de la Medicación , Ritonavir/administración & dosificación , Ritonavir/efectos adversos , Triazoles/administración & dosificación , Triazoles/efectos adversos , Adulto Joven
6.
J Infect Dis ; 213(11): 1717-24, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-26908737

RESUMEN

A proportion of human immunodeficiency virus (HIV)-infected patients develop persistent, stigmatizing human papillomavirus (HPV)-related cutaneous and genital warts and anogenital (pre)cancer. This is the first study to investigate immunogenetic variations that might account for HPV susceptibility and the largest to date to categorize the HPV types associated with cutaneous warts in HIV-positive patients. The HLA class I and II allele distribution was analyzed in 49 antiretroviral (ART)-treated HIV-positive patients with persistent warts, 42 noninfected controls, and 46 HIV-positive controls. The allele HLA-B*44 was more frequently identified in HIV-positive patients with warts (P = .004); a susceptible haplotype (HLA-B*44, HLA-C*05; P = .001) and protective genes (HLA-DQB1*06; P = .03) may also contribute. Cutaneous wart biopsy specimens from HIV-positive patients harbored common wart types HPV27/57, the unusual wart type HPV7, and an excess of Betapapillomavirus types (P = .002), compared with wart specimens from noninfected controls. These findings suggest that HLA testing might assist in stratifying those patients in whom vaccination should be recommended.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/inmunología , Antígenos HLA/inmunología , Papillomaviridae , Infecciones por Papillomavirus/inmunología , Verrugas/inmunología , Adulto , Enfermedad Crónica , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Antígenos HLA/genética , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Papillomaviridae/clasificación , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/complicaciones , Verrugas/complicaciones , Verrugas/virología
7.
Clin Infect Dis ; 61(10): 1582-9, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26202768

RESUMEN

OBJECTIVE: To describe the pharmacokinetics of maraviroc in human immunodeficiency virus (HIV)-infected women during pregnancy and post partum. METHODS: HIV-infected pregnant women receiving maraviroc as part of clinical care had intensive steady-state 12-hour pharmacokinetic profiles performed during the third trimester and ≥2 weeks after delivery. Cord blood samples and matching maternal blood samples were taken at delivery. The data were collected in 2 studies: P1026 (United States) and PANNA (Europe). Pharmacokinetic parameters were calculated. RESULTS: Eighteen women were included in the analysis. Most women (12; 67%) received 150 mg of maraviroc twice daily with a protease inhibitor, 2 (11%) received 300 mg twice daily without a protease inhibitor, and 4 (22%) had an alternative regimen. The geometric mean ratios for third-trimester versus postpartum maraviroc were 0.72 (90% confidence interval, .60-.88) for the area under the curve over a dosing interval (AUCtau) and 0.70 (0.58-0.85) for the maximum maraviroc concentration. Only 1 patient showed a trough concentration (Ctrough) below the suggested target of 50 ng/mL, both during pregnancy and post partum. The median ratio of maraviroc cord blood to maternal blood was 0.33 (range, 0.03-0.56). The viral load close to delivery was <50 copies/mL in 13 women (76%). All children were HIV negative at testing. CONCLUSIONS: Overall maraviroc exposure during pregnancy was decreased, with a reduction in AUCtau and maximum concentration of about 30%. Ctrough was reduced by 15% but exceeded the minimum Ctrough target concentration. Therefore, the standard adult dose seems sufficient in pregnancy. CLINICAL TRIALS REGISTRATION: NCT00825929 and NCT000422890.


Asunto(s)
Fármacos Anti-VIH/farmacocinética , Ciclohexanos/farmacocinética , Infecciones por VIH/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Triazoles/farmacocinética , Adulto , Fármacos Anti-VIH/administración & dosificación , Análisis Químico de la Sangre , Ciclohexanos/administración & dosificación , Europa (Continente) , Femenino , Humanos , Maraviroc , Embarazo , Triazoles/administración & dosificación , Estados Unidos , Adulto Joven
8.
Clin Infect Dis ; 61(5): 809-16, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25944344

RESUMEN

BACKGROUND: The use of raltegravir in human immunodeficiency virus (HIV)-infected pregnant women is important in the prevention of mother-to-child HIV transmission, especially in circumstances when a rapid decline of HIV RNA load is warranted or when preferred antiretroviral agents cannot be used. Physiological changes during pregnancy can reduce antiretroviral drug exposure. We studied the effect of pregnancy on the pharmacokinetics of raltegravir and its safety and efficacy in HIV-infected pregnant women. METHODS: An open-label, multicenter, phase 4 study in HIV-infected pregnant women receiving raltegravir 400 mg twice daily was performed (Pharmacokinetics of Newly Developed Antiretroviral Agents in HIV-Infected Pregnant Women Network). Steady-state pharmacokinetic profiles were obtained in the third trimester and postpartum along with cord and maternal delivery concentrations. Safety and virologic efficacy were evaluated. RESULTS: Twenty-two patients were included, of which 68% started raltegravir during pregnancy. Approaching delivery, 86% of the patients had an undetectable viral load (<50 copies/mL). None of the children were HIV-infected. Exposure to raltegravir was highly variable. Overall area under the plasma concentration-time curve (AUC) and plasma concentration at 12 hours after intake (C12h) plasma concentrations in the third trimester were on average 29% and 36% lower, respectively, compared with postpartum: Geometric mean ratios (90% confidence interval) were 0.71 (.53-.96) for AUC0-12h and 0.64 (.34-1.22) for C12h. The median ratio of raltegravir cord to maternal blood was 1.21 (interquartile range, 1.02-2.17; n = 9). CONCLUSIONS: Raltegravir was well tolerated during pregnancy. The pharmacokinetics of raltegravir showed extensive variability. The observed mean decrease in exposure to raltegravir during third trimester compared to postpartum is not considered to be of clinical importance. Raltegravir can be used in standard dosages in HIV-infected pregnant women. CLINICAL TRIALS REGISTRATION: NCT00825929.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Raltegravir Potásico , Adulto , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/farmacocinética , Fármacos Anti-VIH/uso terapéutico , Área Bajo la Curva , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Recién Nacido , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Raltegravir Potásico/administración & dosificación , Raltegravir Potásico/efectos adversos , Raltegravir Potásico/farmacocinética , Raltegravir Potásico/uso terapéutico
9.
J Antimicrob Chemother ; 70(2): 534-42, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25326090

RESUMEN

OBJECTIVES: To describe the pharmacokinetics of darunavir in pregnant HIV-infected women in the third trimester and post-partum. PATIENTS AND METHODS: This was a non-randomized, open-label, multicentre, Phase IV study in HIV-infected pregnant women recruited from HIV treatment centres in Europe. HIV-infected pregnant women treated with darunavir (800/100 mg once daily or 600/100 mg twice daily) as part of their combination ART were included. Pharmacokinetic curves were recorded in the third trimester and post-partum. A cord blood sample and maternal sample were collected. The study is registered at ClinicalTrials.gov under number NCT00825929. RESULTS: Twenty-four women were included in the analysis [darunavir/ritonavir: 600/100 mg twice daily (n=6); 800/100 mg once daily (n=17); and 600/100 mg once daily (n=1)]. Geometric mean ratios of third trimester versus post-partum (90% CI) were 0.78 (0.60-1.00) for total darunavir AUC0-tau after 600/100 mg twice-daily dosing and 0.67 (0.56-0.82) for total darunavir AUC0-tau after 800/100 mg once-daily dosing. The unbound fraction of darunavir was not different during pregnancy (12%) compared with post-partum (10%). The median (range) ratio of darunavir cord blood/maternal blood was 0.13 (0.08-0.35). Viral load close to delivery was <300 copies/mL in all but two patients. All children were tested HIV-negative and no congenital abnormalities were reported. CONCLUSIONS: Darunavir AUC and Cmax were substantially decreased in pregnancy for both darunavir/ritonavir regimens. This decrease in exposure did not result in mother-to-child transmission. For antiretroviral-naive patients, who are adherent, take darunavir with food and are not using concomitant medication reducing darunavir concentrations, 800/100 mg of darunavir/ritonavir once daily is adequate in pregnancy. For all other patients 600/100 mg of darunavir/ritonavir twice daily is recommended during pregnancy.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/farmacocinética , VIH-1/efectos de los fármacos , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Sulfonamidas/farmacocinética , Adulto , Darunavir , Esquema de Medicación , Quimioterapia Combinada , Femenino , Infecciones por VIH/virología , Inhibidores de la Proteasa del VIH/administración & dosificación , Inhibidores de la Proteasa del VIH/efectos adversos , Humanos , Recién Nacido , Embarazo , Factores de Riesgo , Sulfonamidas/administración & dosificación , Sulfonamidas/efectos adversos , Resultado del Tratamiento , Carga Viral , Adulto Joven
10.
Infect Dis Obstet Gynecol ; 2014: 961375, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25328370

RESUMEN

INTRODUCTION: There are few data regarding the tolerability, safety, or efficacy of antenatal atazanavir. We report our clinical experience of atazanavir use in pregnancy. METHODS: A retrospective medical records review of atazanavir-exposed pregnancies in 12 London centres between 2004 and 2010. RESULTS: There were 145 pregnancies in 135 women: 89 conceived whilst taking atazanavir-based combination antiretroviral therapy (cART), "preconception" atazanavir exposure; 27 started atazanavir-based cART as "first-line" during the pregnancy; and 29 "switched" to an atazanavir-based regimen from another cART regimen during pregnancy. Gastrointestinal intolerance requiring atazanavir cessation occurred in five pregnancies. Self-limiting, new-onset transaminitis was most common in first-line use, occurring in 11.0%. Atazanavir was commenced in five switch pregnancies in the presence of transaminitis, two of which discontinued atazanavir with persistent transaminitis. HIV-VL < 50 copies/mL was achieved in 89.3% preconception, 56.5% first-line, and 72.0% switch exposures. Singleton preterm delivery (<37 weeks) occurred in 11.7% preconception, 9.1% first-line, and 7.7% switch exposures. Four infants required phototherapy. There was one mother-to-child transmission in a poorly adherent woman. CONCLUSIONS: These data suggest that atazanavir is well tolerated and can be safely prescribed as a component of combination antiretroviral therapy in pregnancy.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Oligopéptidos/uso terapéutico , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Piridinas/uso terapéutico , Adulto , Sulfato de Atazanavir , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Infecciones por VIH/virología , Humanos , Londres/epidemiología , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/virología , Resultado del Embarazo , Atención Prenatal , Estudios Retrospectivos , Carga Viral
11.
J Appl Biomech ; 30(4): 594-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24979813

RESUMEN

Wearable accelerometer-based activity monitors (AMs) are used to estimate energy expenditure and ground reaction forces in free-living environments, but a lack of standardized calibration and data reporting methods limits their utility. The objectives of this study were to (1) design an inexpensive and easily reproducible AM testing system, (2) develop a standardized calibration method for accelerometer-based AMs, and (3) evaluate the utility of the system and accuracy of the calibration method. A centrifuge-type device was constructed to apply known accelerations (0-8g) to each sensitive axis of 30 custom and two commercial AMs. Accelerometer data were recorded and matrix algebra and a least squares solution were then used to determine a calibration matrix for the custom AMs to convert raw accelerometer output to units of g's. Accuracy was tested by comparing applied and calculated accelerations for custom and commercial AMs. AMs were accurate to within 4% of applied accelerations. The relatively inexpensive AM testing system (< $100) and calibration method has the potential to improve the sharing of AM data, the ability to compare data from different studies, and the accuracy of AM-based models to estimate various physiological and biomechanical quantities of interest in field-based assessments of physical activity.


Asunto(s)
Aceleración , Acelerometría/instrumentación , Acelerometría/normas , Análisis de Falla de Equipo/instrumentación , Análisis de Falla de Equipo/normas , Transductores/normas , Calibración/normas , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estados Unidos
12.
Med Sci Sports Exerc ; 56(5): 982-989, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37486767

RESUMEN

PURPOSE: The primary goal of this study was to examine changes in peak insole force and cumulative weighted peak force (CWPF)/km with increased step rate in collegiate runners. The secondary goal was to determine whether sacral acceleration correlates with insole force when increasing step rate. METHODS: Twelve collegiate distance runners ran 1000 m outdoors at 3.83 m·s -1 at preferred and 10% increased step rates while insole force and sacral acceleration were recorded. Cumulative weighted peak force/km was calculated from insole force based on cumulative damage models. The effects of step rate on peak insole force and CWPF·km -1 were tested using paired t tests or Wilcoxon tests. Correlation coefficients between peak axial (approximately vertical) sacral acceleration times body mass and peak insole force were calculated on cohort and individual levels. RESULTS: Peak insole force and CWPF·km -1 decreased ( P < 0.001) with increased step rate. Peak axial sacral acceleration did not correlate with peak insole force on the cohort level ( r = 0.35, P = 0.109) but did within individuals (mean, r = 0.69-0.78; P < 0.05). CONCLUSIONS: Increasing step rate may reduce peak vGRF and CWPF·km -1 in collegiate runners. Therefore, clinicians should consider step rate interventions to reduce peak and cumulative vGRF in this population. Individual-specific calibrations may be required to assess changes in peak vGRF in response to increasing step rate using wearable accelerometers.


Asunto(s)
Aceleración , Zapatos , Humanos , Fenómenos Biomecánicos
13.
Bone ; 187: 117180, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38944098

RESUMEN

Recent research has revealed several important pathways of epigenetic regulation leading to transcriptional changes in bone cells. Rest Corepressor 2 (Rcor2) is a coregulator of Lysine-specific histone demethylase 1 (Lsd1), a demethylase linked to osteoblast activity, hematopoietic stem cell differentiation and malignancy of different neoplasms. However, the role of Rcor2 in osteoblast differentiation has not yet been examined in detail. We have previously shown that Rcor2 is highly expressed in mesenchymal stromal cells (MSC) and particularly in the osteoblastic lineage. The role of Rcor2 in osteoblastic differentiation in vitro was further characterized and we demonstrate here that lentiviral silencing of Rcor2 in MC3T3-E1 cells led to a decrease in osteoblast differentiation. This was indicated by decreased alkaline phosphatase and von Kossa stainings as well as by decreased expression of several osteoblast-related marker genes. RNA-sequencing of the Rcor2-downregulated MC3T3-E1 cells showed decreased repression of Rcor2 target genes, as well as significant upregulation of majority of the differentially expressed genes. While the heterozygous, global loss of Rcor2 in vivo did not lead to a detectable bone phenotype, conditional deletion of Rcor2 in limb-bud mesenchymal cells led to a moderate decrease in cortical bone volume. These findings were not accentuated by challenging bone formation by ovariectomy or tibial fracture. Furthermore, a global deletion of Rcor2 led to decreased white adipose tissue in vivo and decreased the capacity of primary cells to differentiate into adipocytes in vitro. The conditional deletion of Rcor2 led to decreased adiposity in fracture callus. Taken together, these results suggest that epigenetic regulation of mesenchymal stromal cell differentiation is mediated by Rcor2, which could thus play an important role in defining the MSC fate.

14.
Int J Toxicol ; 32(2): 130-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23493903

RESUMEN

The fate of dermally applied [(14)C]d-limonene was evaluated in humans and Long-Evans rats. In rats, 5 mg/kg body weight of [(14)C]d-limonene applied dermally to the shaved back under occlusion, resulted in the absorption of approximately 12% of the dose. The absorbed d-limonene was completely metabolized and excreted rapidly, primarily from the urine (80%) with a small fraction (20%) excreted in the feces. There was no long-term retention of the test material in body tissues. In humans, following dermal application of 12 mg of [(14)C]d-limonene in ethanol (1 mL) to the back under nonocclusive conditions (for 1 h after application to allow the material to dry, thereafter under occlusion), only 0.16% of the dose was absorbed and the radioactivity was recovered from the urine. Radioactivity in human feces was below the limit of detection. These results indicate that under conditions of simulated use of fragrances and cosmetics, d-limonene has a low potential for dermal absorption and tissue accumulation, and the d-limonene that is absorbed is rapidly excreted in the urine. Based upon these findings and the knowledge that d-limonene possesses a low-systemic toxicity profile, it is reasonable to conclude that dermal exposure to d-limonene from fragrance and cosmetic applications is highly unlikely to result in any clinically significant human toxicity.


Asunto(s)
Ciclohexenos/administración & dosificación , Ciclohexenos/efectos adversos , Dermis/efectos de los fármacos , Terpenos/administración & dosificación , Terpenos/efectos adversos , Administración Cutánea , Adulto , Animales , Ciclohexenos/farmacocinética , Dermis/metabolismo , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Humanos , Limoneno , Masculino , Perfumes , Ratas , Ratas Long-Evans , Absorción Cutánea , Terpenos/farmacocinética
15.
Int J Toxicol ; 32(1): 39-47, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23385160

RESUMEN

The present studies were conducted to compare the dermal absorption, plasma pharmacokinetics, and excretion of phenylethyl alcohol (PEA) by pregnant and nonpregnant rats, rabbits, and humans. The PEA is a natural fragrance material that is widely used in perfumes, soaps, and lotions and is a major ingredient of natural rose oil. Following dermal (430, 700, or 1400 mg/kg body weight [bw]), gavage (430 mg/kg bw), or dietary (430 mg/kg bw) administration of PEA to rats, plasma concentrations of PEA were found to be low regardless of the route of administration. The plasma concentrations of phenylacetic acid (PAA, the major metabolite of PEA) greatly exceeded the concentrations of PEA and were highest after gavage, followed by dermal then dietary administration. Absorption, distribution, metabolism, and excretion were compared following topical application of ¹4C-labeled PEA to rats, rabbits, and humans (specific activities of dosing solutions: 58-580, 164, and 50 µCi/mL, respectively). In rabbits, the plasma concentration-time profile for PAA was markedly prolonged compared to rats or humans. In humans, only 7.6% of the applied dose of PEA was absorbed, versus 77% in rats and 50% in rabbits. Based on a human dermal systemic exposure of 0.3 mg/kg per day from the use of multiple consumer personal care products containing PEA, a rat dermal no observed adverse effect level of 70 mg/kg per day, and the percentage of dose absorbed in humans, the margin of safety exceeds 2600 concluding that, under normal fragrance use conditions, PEA is not a developmental toxicity hazard for humans.


Asunto(s)
Alcohol Feniletílico/efectos adversos , Alcohol Feniletílico/farmacocinética , Embarazo/metabolismo , Administración Cutánea , Administración Oral , Adulto , Animales , Seguridad de Productos para el Consumidor , Relación Dosis-Respuesta a Droga , Heces/química , Femenino , Humanos , Masculino , Tasa de Depuración Metabólica , Alcohol Feniletílico/sangre , Alcohol Feniletílico/orina , Embarazo/sangre , Embarazo/orina , Conejos , Ratas , Ratas Sprague-Dawley , Absorción Cutánea , Especificidad de la Especie , Distribución Tisular
16.
Animals (Basel) ; 13(11)2023 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-37889766

RESUMEN

Racehorses are susceptible to underrun heel hoof conformation. Racehorses are often shod with nails placed toward the heel. It is unknown if palmar nails restrict or alter hoof deformation in a manner that could promote the development of underrun heel conformation over time with repeated loading. To determine how the addition of palmar nails affects heel deformation during limb loading, hoof expansion and hoof wall deformations were quantified using rosette strain gauges and kinematic markers during in the vitro limb loading of cadaveric limbs that simulated midstance for walk, trot, and canter loads. Nail treatments used to attach a horseshoe to the hoof included: toe nails (T), toe and quarter nails (TQ), and toe, quarter, and heel nails (TQH). The effects of nail treatment on heel expansion and hoof wall deformations were assessed using repeated measures analysis of variance (p < 0.05). Nails placed palmar to the quarters of the hoof decreased heel expansion (p < 0.001). Heel nails resulted in the largest changes in hoof wall principal strain directions distally. The application of nails palmar to the hoof quarters alters hoof wall deformation during limb loading. The continued loading of the hoof with palmer nails could alter hoof conformation over time.

17.
Intensive Care Med ; 48(4): 414-425, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35220473

RESUMEN

PURPOSE: Delirium is common in the critically ill, highly distressing to patients and families and associated with increased morbidity and mortality. Results of studies on preventative use of melatonin in various patient groups have produced mixed results. The aim of this study was to determine whether administration of melatonin decreases the prevalence of delirium in critically ill patients. METHODS: Multicentre, randomized, placebo-controlled, double-blind trial across 12 Australian ICUs recruiting patients from July 2016 to September 2019. Patients of at least 18 years requiring ICU admission with an expected length of stay (LOS) greater than 72 h; enrolled within 48 h of ICU admission. Indistinguishable liquid melatonin (4 mg; n = 419) or placebo (n = 422) was administered enterally at 21:00 h for 14 consecutive nights or until ICU discharge. The primary outcome was the proportion of delirium-free assessments, as a marker of delirium prevalence, within 14 days or before ICU discharge. Delirium was assessed twice daily using the Confusion Assessment Method for ICU (CAM-ICU) score. Secondary outcomes included sleep quality and quantity, hospital and ICU LOS, and hospital and 90-day mortality. RESULTS: A total of 847 patients were randomized into the study with 841 included in data analysis. Baseline characteristics of the participants were similar. There was no significant difference in the average proportion of delirium-free assessments per patient between the melatonin and placebo groups (79.2 vs 80% respectively, p = 0.547). There was no significant difference in any secondary outcomes including ICU LOS (median: 5 vs 5 days, p = 0.135), hospital LOS (median: 14 vs 12 days, p = 0816), mortality at any time point including at 90 days (15.5 vs 15.6% p = 0.948), nor in the quantity or quality of sleep. There were no serious adverse events reported in either group. CONCLUSION: Enteral melatonin initiated within 48 h of ICU admission did not reduce the prevalence of delirium compared to placebo. These findings do not support the routine early use of melatonin in the critically ill.


Asunto(s)
Delirio , Melatonina , Australia , Cuidados Críticos/métodos , Enfermedad Crítica/terapia , Delirio/inducido químicamente , Delirio/tratamiento farmacológico , Delirio/prevención & control , Método Doble Ciego , Humanos , Unidades de Cuidados Intensivos , Melatonina/efectos adversos , Melatonina/uso terapéutico
18.
Eur Arch Otorhinolaryngol ; 268(1): 143-6, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20652711

RESUMEN

The right to confidentiality is a central tenet of the doctor-patient relationship. In the United Kingdom this right to confidentiality is recognised in published GMC guidance. In USA the Healthcare Insurance Portability and Accountability Act of 1996 (HIPAA) strengthened the legal requirement to protect patient information in all forms and failure to do so now constitutes a federal offence. The aims of this study are to assess the acoustic privacy of an otolaryngology outpatient consultation room. Acoustic privacy was measured using the articulation index (AI) and Bamford-Kowal-Bench (BKB) speech discrimination tests. BKB speech tests were calibrated to normal conversational volume (50 dB SPL). Both AI and BKB were calculated in four positions around the ENT clinic: within the consultation room, outside the consulting room door, in the nearest waiting area chair and in the farthest waiting area chair. Tests were undertaken with the clinic room door closed and open to assess the effect on privacy. With the clinic room door closed, mean BKB scores in nearest and farthest waiting area chairs were 51 and 41% respectively. AI scores in the waiting area chairs were 0.03 and 0.02. With the clinic room door open, privacy was lost in both AI and BKB testing, with almost 100% of word discernable at normal talking levels. The results of this study highlight the poor level of speech privacy within a standard ENT outpatient department. AI is a poor predictor or privacy.


Asunto(s)
Otolaringología , Relaciones Médico-Paciente , Privacidad , Derivación y Consulta , Acústica , Instituciones de Atención Ambulatoria , Audiología , Humanos , Pruebas de Discriminación del Habla , Reino Unido
19.
J Am Acad Audiol ; 21(6): 365-79, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20701834

RESUMEN

BACKGROUND: Allowing Medicare beneficiaries to self-refer to audiologists for evaluation of hearing loss has been advocated as a cost-effective service delivery model. Resistance to audiology direct access is based, in part, on the concern that audiologists might miss significant otologic conditions. PURPOSE: To evaluate the relative safety of audiology direct access by comparing the treatment plans of audiologists and otolaryngologists in a large group of Medicare-eligible patients seeking hearing evaluation. RESEARCH DESIGN: Retrospective chart review study comparing assessment and treatment plans developed by audiologists and otolaryngologists. STUDY SAMPLE: 1550 records comprising all Medicare eligible patients referred to the Audiology Section of the Mayo Clinic Florida in 2007 with a primary complaint of hearing impairment. DATA COLLECTION AND ANALYSIS: Assessment and treatment plans were compiled from the electronic medical record and placed in a secured database. Records of patients seen jointly by audiology and otolaryngology practitioners (Group 1: 352 cases) were reviewed by four blinded reviewers, two otolaryngologists and two audiologists, who judged whether the audiologist treatment plan, if followed, would have missed conditions identified and addressed in the otolaryngologist's treatment plan. Records of patients seen by audiology but not otolaryngology (Group 2: 1198 cases) were evaluated by a neurotologist who judged whether the patient should have seen an otolaryngologist based on the audiologist's documentation and test results. Additionally, the audiologist and reviewing neurotologist judgments about hearing asymmetry were compared to two mathematical measures of hearing asymmetry (Charing Cross and AAO-HNS [American Academy of Otolaryngology-Head and Neck Surgery] calculations). RESULTS: In the analysis of Group 1 records, the jury of four judges found no audiology discrepant treatment plans in over 95% of cases. In no case where a judge identified a discrepancy in treatment plans did the audiologist plan risk missing conditions associated with significant mortality or morbidity that were subsequently identified by the otolaryngologist. In the analysis of Group 2 records, the neurotologist judged that audiology services alone were all that was required in 78% of cases. An additional 9% of cases were referred for subsequent medical evaluation. The majority of remaining patients had hearing asymmetries. Some were evaluated by otolaryngology for hearing asymmetry in the past with no interval changes, and others were consistent with noise exposure history. In 0.33% of cases, unexplained hearing asymmetry was potentially missed by the audiologist. Audiologists and the neurotologist demonstrated comparable accuracy in identifying Charing Cross and AAO-HNS pure-tone asymmetries. CONCLUSIONS: Of study patients evaluated for hearing problems in the one-year period of this study, the majority (95%) ultimately required audiological services, and in most of these cases, audiological services were the only hearing health-care services that were needed. Audiologist treatment plans did not differ substantially from otolaryngologist plans for the same condition; there was no convincing evidence that audiologists missed significant symptoms of otologic disease; and there was strong evidence that audiologists referred to otolaryngology when appropriate. These findings are consistent with the premise that audiology direct access would not pose a safety risk to Medicare beneficiaries complaining of hearing impairment.


Asunto(s)
Audiología/economía , Enfermedades del Oído/diagnóstico , Accesibilidad a los Servicios de Salud/economía , Pérdida Auditiva/rehabilitación , Medicare/economía , Derivación y Consulta/economía , Seguridad , Anciano , Análisis Costo-Beneficio , Femenino , Pérdida Auditiva/diagnóstico , Pérdida Auditiva/economía , Pérdida Auditiva/etiología , Pérdida Auditiva Unilateral/diagnóstico , Pérdida Auditiva Unilateral/economía , Pérdida Auditiva Unilateral/etiología , Pérdida Auditiva Unilateral/rehabilitación , Humanos , Masculino , Sistemas de Registros Médicos Computarizados , Otolaringología/economía , Planificación de Atención al Paciente/economía , Enfermedades Retrococleares/diagnóstico , Enfermedades Retrococleares/economía , Enfermedades Retrococleares/etiología , Enfermedades Retrococleares/rehabilitación , Estados Unidos
20.
Antivir Ther ; 14(3): 443-50, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19474478

RESUMEN

BACKGROUND: Pregnancy affects the pharmacokinetics of most protease inhibitors. Saquinavir, when administered in a tablet formulation, has not been studied extensively in this setting. METHODS: A pharmacokinetic, prospective, multicentre trial of HIV type-1-infected pregnant women treated with saquinavir (500 mg tablets) boosted with ritonavir at a dose of 1,000/100 mg twice daily plus a nucleoside backbone was conducted. Pharmacokinetic curves were recorded for 12 h in the second trimester (week 20 +/-2), the third trimester (week 33 +/-2) and post-partum (weeks 4-6). Blood was sampled pre-dosing and at 1, 2, 3, 4, 6, 8, 10 and 12 h post-dosing. Pharmacokinetic parameters were calculated using WinNonlin software version 4.1. RESULTS: A total of 37 women were included in the analysis. Mean (+/-sd) values for saquinavir area under the curve (AUC(0-12h)) were 23.47 h*mg/l (11.92) at week 20 (n=16), 23.65 h*mg/l (9.07) at week 33 (n=31) and 25.00 h*mg/l (11.81) post-partum (n=9). There was no significant difference in the saquinavir AUC(0-12h) when comparing the data during pregnancy and post-partum. Subtherapeutic plasma concentrations of saquinavir (defined as <0.10 mg/l) were not observed throughout the study. No major safety concerns were noted. CONCLUSIONS: Saquinavir exposure in the new tablet formulation generates adequate saquinavir concentrations throughout the course of pregnancy and is safe to use; therefore, no dose adjustment during pregnancy is needed.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/farmacocinética , VIH-1 , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Saquinavir/farmacocinética , Adulto , Esquema de Medicación , Quimioterapia Combinada , Europa (Continente) , Femenino , Inhibidores de la Proteasa del VIH/administración & dosificación , Inhibidores de la Proteasa del VIH/efectos adversos , Humanos , Embarazo , Ritonavir/administración & dosificación , Ritonavir/uso terapéutico , Saquinavir/administración & dosificación , Saquinavir/efectos adversos , Comprimidos , Tailandia , Resultado del Tratamiento
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