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1.
Am J Epidemiol ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38634618

RESUMEN

Women with gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (HDP), and preterm birth (PTB) have excess cardiovascular disease compared to those with uncomplicated births, perhaps related to pre-pregnancy inflammation, dysmetabolism or endothelial dysfunction. We included 1238 women in the Coronary Artery Risk Development in Young Adults Study (1985-2011) with 2215 births classified according to outcomes (term, uncomplicated births were the referent). Repeated measures ANOVA estimated pre-pregnancy, post-pregnancy and biomarker change according to pregnancy outcomes, adjusted for confounders. GDM and HDP groups had higher pre-pregnancy hsCRP (+0.37 [0.08, 0.65]; +0.29 [0.04, 0.55] log mg/L), leptin (+0.29 [0.09, 0.50]; +0.37 [0.17, 0.56] log ng/ml), and lower adiponectin (-0.25 [-0.36, -0.13); -0.11 [-0.22, -0.01] log ng/ml) than those with uncomplicated births and these profiles persisted in magnitude post-pregnancy. Controlling for BMI attenuated most profiles, except lower pre-pregnancy adiponectin remained associated with GDM. PTB without HDP or GDM was related to lower pre-pregnancy hsCRP and sICAM-1 (-0.31 [-0.56, -0.06] log mg/L; -0.05 [-0.09, - 0.01] log ng/ml) and a larger leptin increase from pre- to post-pregnancy, (+0.20 [0.02, 0.37] log ng/ml). Pre-pregnancy inflammation and metabolic dysfunction contributed to GDM and HDP, perhaps due to higher BMI. PTB may be related to adverse metabolic changes post-pregnancy, though the unexpected endothelial biomarker profile warrants further study.

2.
J Exp Biol ; 227(11)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38752366

RESUMEN

The evolution and utilization of limbs facilitated terrestrial vertebrate movement on land, but little is known about how other lateral structures enhance terrestrial locomotion in amphibian fishes without terrestrialized limb structures. Climbing perch (Anabas testudineus) exhibit sustained terrestrial locomotion using uniaxial rotating gill covers instead of appendages. To investigate the role of such simple lateral structures in terrestrial locomotion and the motion-generating mechanism of the corresponding locomotor structure configuration (gill covers and body undulation), we measured the terrestrial kinematics of climbing perch and quantitatively analysed its motion characteristics. The digitized locomotor kinematics showed a unique body postural adjustment ability that enables the regulation of the posture of the caudal peduncle for converting lateral bending force into propulsion. An analysis of the coordination characteristics demonstrated that the motion of the gill cover is kinematically independent of axial undulation, suggesting that the gill cover functions as an anchored simple support pole while axial undulation actively mediates body posture and produces propulsive force. The two identified feature shapes explained more than 87% of the complex lateral undulation in multistage locomotion. The kinematic characteristics enhance our understanding of the underlying coordinating mechanism corresponding to locomotor configurations. Our work provides quantitative insight into the terrestrial locomotor adaptation of climbing perch and sheds light on terrestrial motion potential of locomotor configurations containing a typical aquatic body and restricted lateral structure.


Asunto(s)
Locomoción , Percas , Animales , Locomoción/fisiología , Fenómenos Biomecánicos , Percas/fisiología , Branquias/fisiología
3.
Circulation ; 143(10): 974-987, 2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33517667

RESUMEN

BACKGROUND: Gestational diabetes (GD) leads to earlier onset and heightened risk of type 2 diabetes, a strong risk factor for cardiovascular disease (CVD). However, it is unclear whether attaining normoglycemia can ameliorate the excess CVD risk associated with GD history. This study sought to evaluate GD history and glucose tolerance after pregnancy associated with coronary artery calcification (CAC) in women, a manifestation of atherosclerotic CVD and a predictor of CVD clinical events. METHODS: Data were obtained from the CARDIA study (Coronary Artery Risk Development in Young Adults), a US multicenter, community-based prospective cohort of young Black (50%) and White adults aged 18 to 30 years at baseline (1985-1986). The sample included 1133 women without diabetes at baseline, who had ≥1 singleton births (n=2066) during follow-up, glucose tolerance testing at baseline and up to 5 times during 25 years (1986-2011), GD status, and CAC measurements obtained from 1 or more follow up examinations at years 15, 20, and 25 (2001-2011). CAC was measured by noncontrast cardiac computed tomography; dichotomized as Any CAC (score>0) or No CAC (score=0). Complementary log-log models for interval-censored data estimated adjusted hazard ratios of CAC and 95% confidence intervals for GD history and subsequent glucose tolerance groups (normoglycemia, prediabetes, or incident diabetes) on average 14.7 years after the last birth adjusted for prepregnancy and follow-up covariates. RESULTS: Of 1133 women, 139 (12.3%) reported GD and were 47.6 years of age (4.8 SD) at follow-up. CAC was present in 25% (34/139) of women with GD and 15% (149/994) of women with no GD. In comparison with no GD/normoglycemia, adjusted hazard ratios (95% CIs) were 1.54 (1.06-2.24) for no GD/prediabetes and 2.17 (1.30-3.62) for no GD/incident diabetes, and 2.34 (1.34-4.09), 2.13 (1.09-4.17), and 2.02 (0.98-4.19) for GD/normoglycemia, GD/prediabetes, and GD/incident diabetes, respectively (overall P=0.003). CONCLUSIONS: Women without previous GD showed a graded increase in the risk of CAC associated with worsening glucose tolerance. Women with a history of GD had a 2-fold higher risk of CAC across all subsequent levels of glucose tolerance. Midlife atherosclerotic CVD risk among women with previous GD is not diminished by attaining normoglycemia.


Asunto(s)
Calcio/efectos adversos , Vasos Coronarios/fisiopatología , Diabetes Gestacional/diagnóstico , Prueba de Tolerancia a la Glucosa/métodos , Estudios de Cohortes , Diabetes Gestacional/patología , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Estudios Prospectivos , Factores de Riesgo
4.
Molecules ; 26(21)2021 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-34770813

RESUMEN

Two-dimensional (2D) semiconductors with desirable bandgaps and high carrier mobility have great potential in electronic and optoelectronic applications. In this work, we proposed α-TeB and ß-TeB monolayers using density functional theory (DFT) combined with the particle swarm-intelligent global structure search method. The high dynamical and thermal stabilities of two TeB structures indicate high feasibility for experimental synthesis. The electronic structure calculations show that the two structures are indirect bandgap semiconductors with bandgaps of 2.3 and 2.1 eV, respectively. The hole mobility of the ß-TeB sheet is up to 6.90 × 102 cm2 V-1 s-1. By reconstructing the two structures, we identified two new horizontal and lateral heterostructures, and the lateral heterostructure presents a direct band gap, indicating more probable applications could be further explored for TeB sheets.

5.
Ecotoxicol Environ Saf ; 161: 173-183, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29883871

RESUMEN

Exposure to airborne particulate matter (PM) does great harm to the health of human beings. To date, PM exposure has been closely associated with respiratory and cardiovascular diseases, as well as some types of cancer. As the associations of PM with the adverse health effects are well documented in literatures, the underlying mechanisms have not been completely clarified. With the field of epigenetics rising in recent years, PM-associated epigenetic alterations have gradually turned into the hot research topic. DNA methylation is one of the earliest-discovered and best-studied epigenetic mechanisms, of which the alteration can influence the transcription initiation of genes. A number of studies have been published to demonstrate that PM exposure is linked with DNA methylation patterns in the human genome. DNA methylation is the potential regulator of the biological effects of PM exposure. In the present review, DNA methylation related to PM exposure was elaborated on genome-wide and gene-specific methylation. In particular, genome-wide DNA methylation was composed of the alterations in global methylation content and genome-wide methylation profile; gene-specific methylation included the methylation changes in mechanism-related and disease-specific genes. Representative epidemiological and experimental studies were cited to elucidate the viewpoints, focusing on both PM-related methylation changes and the mediating effects of DNA methylation between PM and the health impacts. This review will provide advantageous clues for subsequent studies on the DNA methylation in relation to PM exposure.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Metilación de ADN , Epigénesis Genética , Material Particulado/toxicidad , Exposición a Riesgos Ambientales , Genoma Humano , Humanos
6.
Cleft Palate Craniofac J ; 54(6): 734-738, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-27518405

RESUMEN

OBJECTIVE: To compare risk for sleep-disordered breathing between children with and without single-suture craniosynostosis. PARTICIPANTS: A total of 184 children with single-suture craniosynostosis and 184 controls. MAIN OUTCOME MEASURES: Parent reported sleep-disordered breathing-related symptoms. RESULTS: Current sleep problems were reported in 19% of patients with single-suture craniosynostosis and 14% of controls (adjusted odds ratio = 1.6; 95% CI, 0.9 to 2.8). Ever having sleep problems was reported in 25% and 23% of cases and controls, respectively (adjusted odds ratio = 1.2; 95% CI, 0.7 to 1.9). Overall, snoring was statistically associated with single-suture craniosynostosis (P = .01) and was more often reported as 2+ nights per week (versus never) in patients with single-suture craniosynostosis (13%) than in controls (4%) (adjusted odds ratio = 3.5; 95% CI, 1.5 to 8.2). CONCLUSIONS: Though preliminary, increased presence of snoring during sleep in children with single-suture craniosynostosis compared with controls suggests that children with isolated single-suture craniosynostosis may be at increased risk for sleep-disordered breathing. Further study using standardized assessments of sleep-disordered breathing is needed.


Asunto(s)
Craneosinostosis/complicaciones , Síndromes de la Apnea del Sueño/etiología , Niño , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Entrevistas como Asunto , Masculino , Factores Socioeconómicos
7.
Toxicology ; 505: 153829, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38740170

RESUMEN

Drug-induced liver injury (DILI) is one of the major concerns during drug development. Wide acceptance of the 3 R principles and the innovation of in-vitro techniques have introduced various novel model options, among which the three-dimensional (3D) cell spheroid cultures have shown a promising prospect in DILI prediction. The present study developed a 3D quadruple cell co-culture liver spheroid model for DILI prediction via self-assembly. Induction by phorbol 12-myristate 13-acetate at the concentration of 15.42 ng/mL for 48 hours with a following 24-hour rest period was used for THP-1 cell differentiation, resulting in credible macrophagic phenotypes. HepG2 cells, PUMC-HUVEC-T1 cells, THP-1-originated macrophages, and human hepatic stellate cells were selected as the components, which exhibited adaptability in the designated spheroid culture conditions. Following establishment, the characterization demonstrated the competence of the model in long-term stability reflected by the maintenance of morphology, viability, cellular integration, and cell-cell junctions for at least six days, as well as the reliable liver-specific functions including superior albumin and urea secretion, improved drug metabolic enzyme expression and CYP3A4 activity, and the expression of MRP2, BSEP, and P-GP accompanied by the bile acid efflux transport function. In the comparative testing using 22 DILI-positive and 5 DILI-negative compounds among the novel 3D co-culture model, 3D HepG2 spheroids, and 2D HepG2 monolayers, the 3D culture method significantly enhanced the model sensitivity to compound cytotoxicity compared to the 2D form. The novel co-culture liver spheroid model exhibited higher overall predictive power with margin of safety as the classifying tool. In addition, the non-parenchymal cell components could amplify the toxicity of isoniazid in the 3D model, suggesting their potential mediating role in immune-mediated toxicity. The proof-of-concept experiments demonstrated the capability of the model in replicating drug-induced lipid dysregulation, bile acid efflux inhibition, and α-SMA upregulation, which are the key features of liver steatosis and phospholipidosis, cholestasis, and fibrosis, respectively. Overall, the novel 3D quadruple cell co-culture spheroid model is a reliable and readily available option for DILI prediction.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Técnicas de Cocultivo , Esferoides Celulares , Humanos , Esferoides Celulares/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Células Hep G2 , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Células THP-1 , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismo , Supervivencia Celular/efectos de los fármacos
8.
IEEE Trans Biomed Eng ; 70(11): 3093-3104, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37192037

RESUMEN

OBJECTIVE: The human hand is known to have excellent manipulation ability compared to other primate hands. Without the palm movements, the human hand would lose more than 40% of its functions. However, uncovering the constitution of palm movements is still a challenging problem involving kinesiology, physiology, and engineering science. METHODS: By recording the palm joint angles during common grasping, gesturing, and manipulation tasks, we built a palm kinematic dataset. Then, a method for extracting the eigen-movements to characterize the common motion correlation relationships of palm joints was proposed to explore the palm movement constitution. RESULTS: This study revealed a palm kinematic characteristic that we named the joint motion grouping coupling characteristic. During natural palm movements, there are several joint groups with a high degree of motor independence, while the movements of joints within each joint group are interdependent. Based on these characteristics, the palm movements can be decomposed into seven eigen-movements. The linear combinations of these eigen-movements can reconstruct more than 90% of palm movement ability. Moreover, combined with the palm musculoskeletal structures, we found that the revealed eigen-movements are associated with joint groups that are defined by muscular functions, which provided a meaningful context for palm movement decomposition. CONCLUSION: This paper suggests that some invariable characteristics underlie the variable palm motor behaviors and can be used to simplify palm movement generation. SIGNIFICANCE: This paper provides important insights into palm kinematics, and helps facilitate motor function assessment and the development of better artificial hands.

9.
Natl Sci Rev ; 10(5): nwad002, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37056428

RESUMEN

Exploring bio-intelligence of human limbs could provide a new perspective for reconstructing missing limbs.

10.
AJOG Glob Rep ; 3(3): 100246, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37645655

RESUMEN

BACKGROUND: Previous studies that evaluated low gestational weight gain or weight loss among prepregnancy obesity classes have not determined the amount of gestational weight gain associated with the lowest risk of adverse perinatal outcomes and neonatal morbidity among singleton term births. OBJECTIVE: This study aimed to evaluate the relationship of specific gestational weight gain categories of weight loss, stable weight, and low gain considered below the 2009 Institute of Medicine guidelines to perinatal outcomes and neonatal morbidity for singleton, term live births among prepregnancy obesity classes. STUDY DESIGN: This was a retrospective cohort study of 18,476 women among 3 classes of prepregnancy obesity, based on measured prepregnancy weight, and delivering a live singleton pregnancy at ≥37 weeks of gestation at a Kaiser Permanente Northern California hospital (2009-2012). Variables from electronic medical records included perinatal outcomes, sociodemographics, and measured prepregnancy and delivery weights to calculate total gestational weight gain, used to define 5 gestational weight gain categories: weight loss (<-2.0 kg), stable weight (-2.0 to +1.9 kg), low gain (+2.0 to 4.9 kg), gain within guidelines (+5.0 to 9.1 kg; referent), and gain above guidelines (>9.1 kg). Logistic regression models estimated adjusted odds ratios and 95% confidence intervals of maternal and newborn perinatal outcomes (hypertensive disorders, cesarean delivery, size for gestational age, length of stay, neonatal intensive care unit admission) associated with gestational weight gain categories stratified by prepregnancy obesity classes 1, 2, and 3. RESULTS: Low gain occurred in 8%, 12%, and 13% of women in obesity class 1 (body mass index, 30.0-34.9), class 2 (body mass index, 35.0-39.9), and class 3 (body mass index, ≥40), respectively. Compared with gestational weight gain within Institute of Medicine guidelines, low gain was associated with similar or improved maternal and newborn perinatal outcomes for all obesity classes without increased odds of neonatal intensive care unit admission, neonatal length of stay ≥3 days, or small for gestational age. The percentages of small for gestational age for the low gain category were 4.4%, 3.0%, and 4.3% among prepregnancy obesity classes 1, 2, and 3, respectively, and comparable with the gestational weight gain within the guideline category (P>.05). The adjusted odds ratios of small-for-gestational age were not statistically significant for all obesity classes; class 1 (1.16; 95% confidence interval, 0.79-1.71) , class 2 (1.05; 95% confidence interval 0.58-1.93), and class 3 (2.03; 95% confidence interval 0.97-4.27). CONCLUSION: Lower gestational weight gain of +2.0 to 4.9 kg showed the most favorable perinatal outcomes, without higher small for gestational age or neonatal morbidity for all obesity classes.

11.
Front Bioeng Biotechnol ; 11: 1140262, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37214291

RESUMEN

Introduction: It is well known that the common chimpanzee, as both the closest living relative to humans and a facultative bipedal, has the capability of bipedal standing but cannot do so fully upright. Accordingly, they have been of exceeding significance in elucidating the evolution of human bipedalism. There are many reasons why the common chimpanzee can only stand with its hips-knees bent, such as the distally oriented long ischial tubercle and the almost absent lumbar lordosis. However, it is unknown how the relative positions of their shoulder-hip-knee-ankle joints are coordinated. Similarly, the distribution of the biomechanical characteristics of the lower-limb muscles and the factors that affect the erectness of standing as well as the muscle fatigue of the lower limbs remain a mystery. The answers are bound to light up the evolutional mechanism of hominin bipedality, but these conundrums have not been shed much light upon, because few studies have comprehensively explored the effects of skeletal architecture and muscle properties on bipedal standing in common chimpanzees. Methods: Thus, we first built a musculoskeletal model comprising the head-arms-trunk (HAT), thighs, shanks, and feet segments of the common chimpanzee, and then, the mechanical relationships of the Hill-type muscle-tendon units (MTUs) in bipedal standing were deduced. Thereafter, the equilibrium constraints were established, and a constrained optimization problem was formulated where the optimization objective was defined. Finally, thousands of simulations of bipedal standing experiments were performed to determine the optimal posture and its corresponding MTU parameters including muscle lengths, muscle activation, and muscle forces. Moreover, to quantify the relationship between each pair of the parameters from all the experimental simulation outcomes, the Pearson correlation analysis was employed. Results: Our results demonstrate that in the pursuit of the optimal bipedal standing posture, the common chimpanzee cannot simultaneously achieve maximum erectness and minimum muscle fatigue of the lower limbs. For uni-articular MTUs, the relationship between muscle activation, relative muscle lengths, together with relative muscle forces, and the corresponding joint angle is generally negatively correlated for extensors and positively correlated for flexors. For bi-articular MTUs, the relationship between muscle activation, coupled with relative muscle forces, and the corresponding joint angles does not show the same pattern as in the uni-articular MTUs. Discussion: The results of this study bridge the gap between skeletal architecture, along with muscle properties, and biomechanical performance of the common chimpanzee during bipedal standing, which enhances existing biomechanical theories and advances the comprehension of bipedal evolution in humans.

12.
J Am Heart Assoc ; 12(15): e029617, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37435795

RESUMEN

Background Clinical risk factors, a single blood pressure (BP) measurement, current biomarkers, and biophysical parameters can effectively identify risk of early-onset preeclampsia but have limited ability to predict later-onset preeclampsia and gestational hypertension. Clinical BP patterns hold promise to improve early risk stratification for hypertensive disorders of pregnancy. Methods and Results After excluding preexisting hypertension, heart, kidney, or liver disease, or prior preeclampsia, the retrospective cohort (n=249 892) all had systolic BP <140 mm Hg and diastolic BP <90 mm Hg or a single BP elevation ≤20 weeks' gestation, prenatal care at <14 weeks' gestation, and a still or live birth delivery at Kaiser Permanente Northern California hospitals (2009-2019). The sample was randomly split into development (N=174 925; 70%) and validation (n=74 967; 30%) data sets. Predictive performance of multinomial logistic regression models for early-onset (<34 weeks) preeclampsia, later-onset (≥34 weeks) preeclampsia, and gestational hypertension was evaluated in the validation data set. There were 1008 (0.4%), 10 766 (4.3%), and 11 514 (4.6%) patients with early-onset preeclampsia, later-onset preeclampsia, and gestation hypertension, respectively. Models with 6 systolic BP trajectory groups (0-20 weeks' gestation) plus standard clinical risk factors performed substantially better than risk factors alone to predict early- and later-onset preeclampsia and gestational hypertension, with C-statistics (95% CIs) of 0.747 (0.720-0.775), 0.730 (0.722-0.739), and 0.768 (0.761-0.776) versus 0.688 (0.659-0.717), 0.695 (0.686-0.704) and 0.692 (0.683-0.701), respectively, with excellent calibration (Hosmer-Lemeshow P=0.99, 0.99, and 0.74, respectively). Conclusions Early pregnancy BP patterns up to 20 weeks' gestation plus clinical, social, and behavioral factors more accurately discriminate hypertensive disorders of pregnancy risk among low-to-moderate risk pregnancies. Early pregnancy BP trajectories improve risk stratification to reveal higher-risk individuals hidden within ostensibly low-to-moderate risk groups and lower-risk individuals considered at higher risk by US Preventive Services Task Force criteria.


Asunto(s)
Hipertensión Inducida en el Embarazo , Hipertensión , Preeclampsia , Embarazo , Femenino , Humanos , Hipertensión Inducida en el Embarazo/diagnóstico , Hipertensión Inducida en el Embarazo/epidemiología , Preeclampsia/diagnóstico , Preeclampsia/epidemiología , Preeclampsia/prevención & control , Presión Sanguínea , Estudios Retrospectivos , Determinación de la Presión Sanguínea
14.
Obesity (Silver Spring) ; 30(2): 524-534, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35080338

RESUMEN

OBJECTIVE: Gestational weight gain (GWG) above recommendations is a risk factor for adverse maternal, perinatal, and long-term outcomes. This study hypothesized that prepregnancy weight gain may portend excess GWG. METHODS: Among 1,126 women (51% of whom were of Black race) in the Coronary Artery Risk Development in Young Adults (CARDIA) study with post-baseline births, the prepregnancy annual rate of BMI change per woman was estimated (slope; 5 years before pregnancy) and was related to the risk of GWG above Institute of Medicine recommendations using mixed-effects models (binary) and GWG z score (continuous), adjusting for confounders, and stratified by prepregnancy overweight/obesity status. RESULTS: A total of 626 women (56%) had excess GWG. Each standard deviation increase in prepregnancy BMI (0.16 kg/m2 per year) was associated with an 18% increased risk of excess GWG (95% CI: 1.13-1.23), adjusted for covariates. Stratified results showed an association for women without overweight or obesity (adjusted relative risk = 1.71 [95% CI: 1.38-2.13]) but not among those with overweight or obesity (adjusted relative risk = 0.98 [95% CI: 0.91-1.05]). When evaluated as a z score, prepregnancy weight gain was associated with higher GWG among women with and without overweight or obesity (mean = 0.24 [0.10] and 0.28 [0.12] z score, respectively). CONCLUSIONS: Weight gain before pregnancy is associated with higher GWG during pregnancy. Assessment of prepregnancy weight changes may identify those at risk for high GWG.


Asunto(s)
Ganancia de Peso Gestacional , Complicaciones del Embarazo , Índice de Masa Corporal , Femenino , Humanos , Obesidad/complicaciones , Sobrepeso/complicaciones , Embarazo , Complicaciones del Embarazo/epidemiología , Factores de Riesgo , Aumento de Peso , Adulto Joven
15.
IEEE Trans Cybern ; 52(12): 13225-13236, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34662283

RESUMEN

How to generate anthropomorphic reaching movement remains a challenging problem in service robots and human motor function repair/reconstruction equipment. However, there is no universally accepted computational model in the literature for reproducing the motion of the human upper limb. In response to the problem, this article presents a computational framework for generating reaching movement endowed with human motion characteristics that imitated the mechanism in the control and realization of human upper limb motions. This article first establishes the experimental paradigm of human upper limb functional movements and proposes the characterization of human upper limb movement characteristics and feature movement clustering methods in the joint space. Then, according to the specific task requirements of the upper limb, combined with the human sensorimotor model, the estimation method of the human upper limb natural postures was established. Next, a continuous task parametric model matching the characteristic motion class is established by using the Gaussian mixture regression method. The anthropomorphic motion generation method with the characteristics of the smooth trajectory and the ability of natural obstacle avoidance is proposed. Finally, the anthropomorphic motion generation method proposed in this article is verified by a human-like robot. The measurement index of the human-likeness degree of the trajectory is given. The experimental results show that for all four tested tasks, the human-likeness degrees were greater than 90.8%, and the trajectories' jerk generated by this method is very similar to the trajectories' jerk of humans, which validates the proposed method.


Asunto(s)
Robótica , Humanos , Robótica/métodos , Extremidad Superior/fisiología , Movimiento/fisiología , Postura
16.
R Soc Open Sci ; 8(4): 210161, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33996133

RESUMEN

Humans show a variety of locomotor behaviours in daily living, varying in locomotor modes and interaction styles with the external environment. However, how this excellent motor ability is formed, whether there are some invariants underlying various locomotor behaviours and simplifying their generation, and what factors contribute to the invariants remain unclear. Here, we find three common kinematic synergies that form the six joint motions of one lower limb during walking, running, hopping and sitting-down-standing-up (movement variance accounted for greater than 90%), through identifying the coordination characteristics of 36 lower limb motor tasks in diverse environments. This finding supports the notion that humans simplify the generation of various motor behaviours through re-using several basic motor modules, rather than developing entirely new modules for each behaviour. Moreover, a potential link is also found between these synergies and the unique biomechanical characteristics of the human musculoskeletal system (muscular-articular connective architecture and bone shape), and the patterns of inter-joint coordination are consistent with the energy-saving mechanism in locomotion by using biarticular muscles as efficient mechanical energy transducers between joints. Altogether, our work helps understand the formation mechanisms of human locomotion from a holistic viewpoint and evokes inspirations for the development of artificial limbs imitating human motor ability.

17.
Bioinspir Biomim ; 16(4)2021 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-33202385

RESUMEN

The unique morphological bases of human hands, which are distinct from other primates, endow them with excellent grasping and manipulative abilities. However, the lack of understanding of human hand morphology and its parametric features is a major obstacle in the scientific design of prosthetic hands. Existing designs of prosthetic hand morphologies mostly adopt engineering-based methods, which depend on human experience, direct measurements of human hands, or numerical simulation/optimization. This paper explores for the first time a science-driven design method for prosthetic hand morphology, aiming to facilitate the development of prosthetic hands with human-level dexterity. We first use human morphological, movement, and postural data to quantitatively cognize general morphological characteristics of human hands in static, dynamic, functional, and non-functional perspectives. Taking these cognitions as bases, we develop a method able to quickly transfer human morphological parameters to prosthetic hands and endow the prosthetic hands with great grasping/manipulative potential at the same time. We apply this method to the design of an advanced prosthetic hand (called X-hand II) embedded with compact actuating systems. The human-size prosthetic hand can reach wide grasping/manipulative ranges close to those of human hands, replicate various daily grasping types and even execute dexterous in-hand manipulation. This science-driven method may also inspire other artificial limb and bionic robot designs.


Asunto(s)
Miembros Artificiales , Mano , Animales , Biónica , Fuerza de la Mano , Humanos , Movimiento
18.
World J Clin Cases ; 9(25): 7593-7599, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34616831

RESUMEN

BACKGROUND: Infliximab (IFX) is an anti-tumor necrosis factor alpha (TNF-α) agent that is widely used for the management of a variety of autoimmune and inflammatory diseases, including Crohn's disease (CD). As a result of its increasing administration, new complications have emerged. Hemorrhagic pericardial effusion, secondary to IFX therapy, is a rare but life-threatening complication. CASE SUMMARY: A 27-year-old man was diagnosed with CD (Montreal A2L3B1) 6 years prior. After failing to respond to mesalazine and methylprednisolone, he took the first dose of IFX 300 mg based on his weight (60 kg, dose 5 mg/kg) on December 3, 2018. He responded well to this therapy. However, on January 21, 2019, 1 wk after the third injection, he suddenly developed dyspnea, fever, and worsening weakness and was admitted to our hospital. On admission, computed tomography scan of the chest revealed a large pericardial effusion and a small right-side pleural effusion. An echocardiogram showed a large pericardial effusion and normal left ventricular function. Then successful ultrasound-guided pericardiocentesis was performed and 600 mL hemorrhagic fluid was drained. There was no evidence of infection and the concentrations of TNF-α, IFX, and anti-IFX antibody were 7.09 pg/mL (reference range < 8.1 pg/mL), < 0.4 µg/mL (> 1.0 µg/mL), and 373 ng/mL (< 30 ng/mL), respectively. As the IFX instruction manual for injection does mention pericardial effusion as a rare adverse reaction (≥ 1/10000, < 1/1000), so we discontinued the IFX. Monitoring of the patient's echocardiogram for 2 mo without IFX therapy showed no recurrence of hemorrhagic pericardial effusion. Follow-up visits and examinations every 3 to 6 mo until April 2021 showed no recurrence of CD or pericardial effusion. CONCLUSION: This is a case of hemorrhagic pericardial effusion following treatment with IFX. It is a rare but life-threatening complication of IFX. Early recognition helps prevent the occurrence of hemorrhagic pericardial effusion and minimize the impact on the natural evolution of the disease.

19.
J Hazard Mater ; 385: 121566, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-31761645

RESUMEN

Up to now, while some toxicological studies have identified pulmonary fibrosis immediately induced by long-term PM2.5 exposure, there has been no evidence indicating, whether short-term exposure can lead to post-exposure development of pulmonary fibrosis. Here, we treated rats with PM2.5 for 1 month (10 times), followed by normal feeding for 18 months. 18F-FDG intake, which is linked with the initiation and development of pulmonary fibrosis in living bodies, was found to gradually increase in lung following exposure through micro PET/CT imaging. Histolopathological examination revealed continuous deterioration of pulmonary injury post-exposure. Collagen deposition and hydroxyproline content continued to increase all along in the post-exposure duration, indicating pulmonary fibrosis development. Chronic and persistent induction of pulmonary inflammatory gene expression (Tnf, Il1b, Il6, Ccl2, and Icam1), epithelial mesenchymal transition (EMT, reduction of E-cadherin and elevation of fibronectin) and RelA/p65 upregulation, as well as serum inflammatory cytokine production, were also found in PM2.5-treated rats. Pulmonary oxidative stress, manifested by increase of MDA and decrease of GSH and SOD, was induced during exposure but disappeared in later post-exposure duration. These results suggested that short-term PM2.5 exposure could lead to sustained post-exposure pulmonary fibrosis development, which was mediated by oxidative-stress-initiated NF-κB/inflammation/EMT pathway.


Asunto(s)
Pulmón/efectos de los fármacos , Material Particulado/toxicidad , Fibrosis Pulmonar/inducido químicamente , Animales , Citocinas/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Masculino , Estrés Oxidativo , Neumonía/metabolismo , Neumonía/patología , Tomografía Computarizada por Tomografía de Emisión de Positrones , Ratas , Ratas Sprague-Dawley
20.
Placenta ; 89: 99-106, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-32056560

RESUMEN

INTRODUCTION: Preterm birth is a heterogeneous phenotype, with placental abnormalities underlying many cases. The etiology of preterm births that occur in the absence of placental abnormalities, however, remain enigmatic and we considered that early pregnancy biomarkers may provide clues. METHODS: Women from a hospital-based cohort (2008-2012, n = 397) were randomly selected within 6 strata of term and preterm birth with and without placental decidual vasculopathy (arteriopathy), intrauterine inflammation/infection (acute chorioamnionitis), or no lesions. Lipids and inflammatory markers were analyzed in first trimester samples (12.5 ± 0.6 weeks) and related to outcome groups (referent, term births with no lesions). Factor analysis then clustered analytes and related these to preterm birth groups, adjusted for covariates and stratified by pre-pregnancy obesity. RESULTS: Three biomarker patterns were identified. Immune activation cytokines (33% of the variance) were associated with preterm birth with no lesions (aOR 1.5, 95%CI 1.1-2.1), particularly among obese women. In contrast, inflammatory chemokines (9% of variance) were associated with term and preterm vasculopathy among non-obese women (aOR 2.6 [1.3, 4.7] and 2.0 [1.1, 3.0], respectively). DISCUSSION: The early pregnancy maternal immune profile is related to preterm births classified according to placental lesions, and these associations vary according to obesity status.


Asunto(s)
Corioamnionitis/patología , Citocinas/sangre , Inflamación/patología , Placenta/patología , Nacimiento Prematuro/patología , Útero/patología , Adulto , Biomarcadores/sangre , Corioamnionitis/sangre , Femenino , Humanos , Inflamación/sangre , Lípidos/sangre , Embarazo , Nacimiento Prematuro/sangre , Adulto Joven
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