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PURPOSE: This study investigated the effects of a 12-week gait retraining program on the morphological and mechanical properties of the Achilles tendon (AT) during running on the basis of real-time dynamic ultrasound imaging. METHODS: A total of 30 male recreational runners who were used to wearing cushioned shoes with a rearfoot strike (RFS) pattern were recruited. They were randomized into a retraining group (RG, n = 15) and a control group (CG, n = 15). The RG group was asked to run in five-fingered minimalist shoes with a forefoot strike (FFS) pattern, and the CG group was asked to keep their strike pattern. Three training sessions were performed per week. All the participants in RG uploaded running tracks obtained through a mobile application (.jpg) after each session for training supervision. The ground reaction force, kinematics, and kinetics of the ankle joint at 10 km/h were collected using an instrumented split-belt treadmill and a motion capture system. The morphological (length and cross-sectional area) and mechanical characteristics (force, stress, strain, etc.) of AT in vivo were recorded and calculated with a synchronous ultrasonic imaging instrument before and after the intervention. Repeated two-way ANOVA was used to compare the aforementioned parameters. RESULTS: A total of 28 participants completed the training. The strike angle of RG after training was significantly smaller than that before training and significantly smaller than that of CG after training (F (1, 13) = 23.068, p < 0.001, partial η2 = 0.640). The length (F (1, 13) = 10.086, p = 0.007, partial η2 = 0.437) and CSA (F (1, 13) = 7.475, p = 0.017, partial η2 = 0.365) of AT in RG increased after training. A significant main effect for time was observed for the time-to-peak AT force (F (1, 13) = 5.225, p = 0.040, partial η2 = 0.287), average (F (1, 13) = 7.228, p = 0.019, partial η2 = 0.357), and peak AT loading rate (F (1, 13) = 11.687, p = 0.005, partial η2 = 0.473). CONCLUSION: Preliminary evidence indicated that a 12-week gait retraining program could exert a beneficial effect on AT. 57% (8/14) runners in RG shifted from RFS to FFS pattern. Although not all runners were categorized as FFS pattern after the intervention, their foot strike angle was reduced. Retraining primarily positively promoted AT morphological properties (i.e., CSA and length) to strengthen AT capability for mechanical loading.
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Tendão do Calcâneo , Humanos , Masculino , Tendão do Calcâneo/diagnóstico por imagem , Articulação do Tornozelo , Fenômenos Biomecânicos , Pé , Marcha , Extremidade Inferior , SapatosRESUMO
The effects of a 12-week gait retraining program on the adaptation of the medial gastrocnemius (MG) and muscle-tendon unit (MTU) were investigated. 26 runners with a rearfoot strike pattern (RFS) were randomly assigned to one of two groups: gait retraining (GR) or control group (CON). MG ultrasound images, marker positions, and ground reaction forces (GRF) were collected twice during 9 km/h of treadmill running before and after the intervention. Ankle kinetics and the MG and MTU behavior and dynamics were quantified. Runners in the GR performed gradual 12-week gait retraining transitioning to a forefoot strike pattern. After 12-week, (1) ten participants in each group completed the training; eight participants in GR transitioned to non-RFS with reduced foot strike angles; (2) MG fascicle contraction length and velocity significantly decreased after the intervention for both groups, whereas MG forces increased after intervention for both groups; (3) significant increases in MTU stretching length for GR and peak MTU recoiling velocity for both groups were observed after the intervention, respectively; (4) no significant difference was found for all parameters of the series elastic element. Gait retraining might potentially influence the MG to operate at lower fascicle contraction lengths and velocities and produce greater peak forces. The gait retraining had no effect on SEE behavior and dynamics but did impact MTU, suggesting that the training was insufficient to induce mechanical loading changes on SEE behavior and dynamics.
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Marcha , Músculo Esquelético , Corrida , Sapatos , Tendões , Humanos , Corrida/fisiologia , Músculo Esquelético/fisiologia , Marcha/fisiologia , Masculino , Fenômenos Biomecânicos , Adulto , Tendões/fisiologia , Adulto Jovem , Feminino , Ultrassonografia , Adaptação FisiológicaRESUMO
BACKGROUND: Transfer to the ICU is common following non-cardiac surgeries, including radical colorectal cancer (CRC) resection. Understanding the judicious utilization of costly ICU medical resources and supportive postoperative care is crucial. This study aimed to construct and validate a nomogram for predicting the need for mandatory ICU admission immediately following radical CRC resection. METHODS: Retrospective analysis was conducted on data from 1003 patients who underwent radical or palliative surgery for CRC at Ningxia Medical University General Hospital from August 2020 to April 2022. Patients were randomly assigned to training and validation cohorts in a 7:3 ratio. Independent predictors were identified using the least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression in the training cohort to construct the nomogram. An online prediction tool was developed for clinical use. The nomogram's calibration and discriminative performance were assessed in both cohorts, and its clinical utility was evaluated through decision curve analysis (DCA). RESULTS: The final predictive model comprised age (P = 0.003, odds ratio [OR] 3.623, 95% confidence interval [CI] 1.535-8.551); nutritional risk screening 2002 (NRS2002) (P = 0.000, OR 6.129, 95% CI 2.920-12.863); serum albumin (ALB) (P = 0.013, OR 0.921, 95% CI 0.863-0.982); atrial fibrillation (P = 0.000, OR 20.017, 95% CI 4.191-95.609); chronic obstructive pulmonary disease (COPD) (P = 0.009, OR 8.151, 95% CI 1.674-39.676); forced expiratory volume in 1 s / Forced vital capacity (FEV1/FVC) (P = 0.040, OR 0.966, 95% CI 0.935-0.998); and surgical method (P = 0.024, OR 0.425, 95% CI 0.202-0.891). The area under the curve was 0.865, and the consistency index was 0.367. The Hosmer-Lemeshow test indicated excellent model fit (P = 0.367). The calibration curve closely approximated the ideal diagonal line. DCA showed a significant net benefit of the predictive model for postoperative ICU admission. CONCLUSION: Predictors of ICU admission following radical CRC resection include age, preoperative serum albumin level, nutritional risk screening, atrial fibrillation, COPD, FEV1/FVC, and surgical route. The predictive nomogram and online tool support clinical decision-making for postoperative ICU admission in patients undergoing radical CRC surgery. TRIAL REGISTRATION: Despite the retrospective nature of this study, we have proactively registered it with the Chinese Clinical Trial Registry. The registration number is ChiCTR2200062210, and the date of registration is 29/07/2022.
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Neoplasias Colorretais , Unidades de Terapia Intensiva , Nomogramas , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Neoplasias Colorretais/cirurgia , Idoso , Medição de Risco/métodos , Complicações Pós-Operatórias/epidemiologia , Admissão do PacienteRESUMO
BACKGROUND: This study aims to investigate the effect of preoperative sleep quality on the target plasma concentration of propofol and postoperative sleep in patients undergoing painless gastroscopy. METHODS: Ninety-three outpatients aged 45 to 64 years with body mass index (BMI) of 18.5-30 kg/m2 and ASA grades of I or II, who underwent painless gastroscopy, were selected. All patients were evaluated by the Athens insomnia scale (AIS) before the painless gastroscopy. The patients were divided into two groups according to the AIS score evaluated before painless gastroscopy: normal sleep group (group N, AIS score < 4 points, 47 cases) and sleep disorder group (group D, AIS score > 6 points, 46 cases). The target-controlled infusion (TCI) of propofol (Marsh model) was used for general anesthesia, the Bispectral index (BIS) was used to monitor the depth of anesthesia, and the BIS was maintained between 50 and 65 during the painless gastroscopy. The target plasma concentration (Cp) of propofol was recorded when the patient's eyelash reflex disappeared (T1), before the painless gastroscopy (T2), at the time of advancing the gastroscope (T3) and during the painless gastroscopy (T4), and the infusion rate per body surface area of propofol was calculated. The patient's AIS score was followed up by telephone at day 1, day 3, 1 week, and 1 month after the painless gastroscopy to assess the postoperative sleep of the patient. The occurrence of adverse reactions during the painless gastroscopy was recorded; the patient's satisfaction and the endoscopist's satisfaction with the anesthesia effect were compared between the two groups. RESULTS: Compared with group N, the Cp at each time point and the infusion rate per body surface area of propofol in group D was increased significantly (P < 0.05); compared with the AIS scores before the painless gastroscopy, the AIS scores of the two groups of patients were significantly increased day 1 after the painless gastroscopy (P < 0.05); there were no significant differences in the AIS scores of the two groups at day 3, 1 week, and 1 month after the painless gastroscopy (P > 0.05). There were no statistically significant differences in the occurrence of adverse reactions and the patient's satisfaction and the endoscopist's satisfaction with the anesthesia effect between the two groups (P > 0.05). CONCLUSION: The preoperative sleep disturbance will increase the Cp and the infusion rate per body surface area of propofol in patients undergoing painless gastroscopy. Propofol only affects the patients' sleep for day 1 after the painless gastroscopy. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2100045332) on 12/04/2021.
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Propofol , Humanos , Qualidade do Sono , Gastroscopia , Anestesia Geral , Pacientes Ambulatoriais , Anestésicos IntravenososRESUMO
BACKGROUND: Cricothyrotomy is a procedure performed to establish an airway in critical airway events. It is performed only rarely and anesthesiologists are often unprepared when called upon to perform it. This study aimed to simulate cricothyrotomy using pig larynx and trachea models to help anesthesiologists master cricothyrotomy and improve the ability to establish cricothyrotomy quickly. METHODS: The porcine larynx and trachea were dissected and covered with pigskin to simulate the structure of the anterior neck of a human patient. An animal model of cricothyrotomy was established. Forty anesthesiologists were randomly divided into four groups. Each physician performed three rounds of cricothyrotomy, and recorded the time to accomplish each successful operation. After training the cricothyrotomy procedure, a questionnaire survey was conducted for the participating residents using a Likert scale. The participants were asked to score the utility of the training course on a scale of 1 ((minimum) to 5 ((maximum). RESULTS: Through repeated practice, compared with the time spent in the first round of the operation (67 ± 29 s), the time spent in the second round of the operation (47 ± 21 s) and the time spent in the third round of the operation (36 ± 11 s) were significantly shortened (P < 0.05). Results of the survey after training were quite satisfied, reflecting increased the ability of proficiency in locating the cricothyroid membrane and performing a surgical cricothyrotomy. CONCLUSION: The porcine larynx and trachea model is an excellent animal model for simulating and practicing cricothyrotomy, helping anesthesiologists to master cricothyrotomy and to perform it proficiently when required.
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Manuseio das Vias Aéreas , Traqueia , Animais , Humanos , Suínos , Traqueia/cirurgia , Manuseio das Vias Aéreas/métodosRESUMO
This study aims to quantify how habitual foot strike patterns would affect ankle kinetics and the behavior and mechanics of the medial gastrocnemius-tendon unit (MTU) during running. A total of 14 runners with non-rearfoot strike patterns (NRFS) and 15 runners with rearfoot strike patterns (RFS) ran on an instrumented treadmill at a speed of 9 km/h. An ultrasound system and a motion capture system were synchronously triggered to collect the ultrasound images of the medial gastrocnemius (MG) and marker positions along with ground reaction forces (GRF) during running. Ankle kinetics (moment and power) and MG/MTU behavior and mechanical properties (MG shortening length, velocity, force, power, MTU shortening/lengthening length, velocity, and power) were calculated. Independent t-tests were performed to compare the two groups of runners. Pearson correlation was conducted to detect the relationship between foot strike angle and the MTU behavior and mechanics. Compared with RFS runners, NRFS runners had 1) lower foot strike angles and greater peak ankle moments; 2) lower shortening/change length and contraction velocity and greater MG peak force; 3) greater MTU lengthening, MTU shortening length and MTU lengthening velocity and power; 4) the foot strike angle was positively related to the change of fascicle length, fascicle contraction length, and MTU shortening length during the stance phase. The foot strike angle was negatively related to the MG force and MTU lengthening power. The MG in NRFS runners appears to contract with greater force in relatively isometric behavior and at a slower shortening velocity. Moreover, the lengthening length, the lengthening velocity of MTU, and the MG force were greater in habitual NRFS runners, leading to a stronger stretch reflex response potentially.
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Corrida , Tendões , Humanos , Tendões/diagnóstico por imagem , Pé , Extremidade Inferior , Articulação do TornozeloRESUMO
OBJECTIVE: This study aimed to investigate the effects of morning and afternoon surgeries on the early postoperative sleep function in patients undergoing general anesthesia. METHODS: Fifty nine patients, aged 18-60 years, American society of anaesthesiologists (ASA) grade I or II, Body mass index of 18.5-28 kg/m2, undergoing laparoscopic myomectomy under total intravenous anesthesia, were included in the study. These patients were divided into two groups according to the start time of anesthesia: morning surgery group (group A, 8:00-12:00) and afternoon surgery group (group P, 14:00-18:00). The sleep conditions of the two groups of patients were evaluated by the Athens Insomnia Scale (AIS) one day before and one day after the operation. A total score of > 6 was regarded as postoperative sleep disturbance. The incidences of sleep disturbance one day after the operation in two groups were compared. The bispectral Index assessed the patient's total sleep duration, sleep efficiency, and overall quality of sleep from 21:00 to 6:00 on the first night after surgery. Plasma concentrations of melatonin and cortisol at 6:00 am 1 day before surgery, 1 day after surgery were measured by ELISA, and rapid random blood glucose was measured. RESULTS: The total AIS score, overall quality of sleep, total sleep duration, and final awakening earlier than desired scores of the two groups of patients on the first night after surgery were significantly increased compared with preoperative scores (P < 0.01). In group P, the sleep induction and the physical and mental functioning during the day scores increased significantly after surgery compared with preoperative scores (P < 0.05). The postoperative AIS scores in group P increased significantly compared with those in group A (P < 0.01). The incidence of postoperative sleep disturbances (70.0%) in group P was significantly higher than that in group A (37.9%) (P < 0.05). Compared with group A, the total sleep duration under BIS monitoring in group P was significantly shorter, the sleep efficiency and the overall quality of sleep was significantly reduced (P < 0.01). Compared with those in group A, the level of melatonin on 1 d after surgery in group P was significantly decreased, and the level of cortisol in group P was significantly increased. There were no significant differences between the two groups in the levels of postoperative blood glucose and pain. CONCLUSION: Both morning and afternoon surgeries have significant impacts on the sleep function in patients undergoing general anesthesia, while afternoon surgery has a more serious impact on sleep function. TRIAL REGISTRATION: ClinicalTrials, NCT04103528. Registered 24 September 2019-Retrospectively registered, http://www. CLINICALTRIALS: gov/ NCT04103528.
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Melatonina , Transtornos do Sono-Vigília , Anestesia Geral , Glicemia , Humanos , Hidrocortisona , Período Pós-Operatório , Qualidade do Sono , Transtornos do Sono-Vigília/epidemiologiaRESUMO
OBJECTIVE: This study aimed to examine the effects of combining transcranial direct current stimulation (tDCS) and foot core exercise (FCE) on the sensorimotor function of the foot (i.e., toe flexor strength and passive ankle kinesthesia) and static balance. METHODS: In this double-blinded and randomized study, 30 participants were randomly assigned into two groups: tDCS combined with FCE and sham combined with FCE (i.e., control group). The participants received 2 mA stimulation for 20 min concurrently with FCE over 4 weeks (i.e., three sessions per week). After the first two groups completed the intervention, a reference group (FCE-only group) was included to further explore the placebo effects of sham by comparing it with the control group. Foot muscle strength, passive ankle kinesthesia, and static balance were assessed at baseline and after the intervention. RESULTS: Compared with the control group and baseline, tDCS combined with FCE could increase toe flexor strength (p < 0.001) and decrease the passive kinesthesia threshold of ankle eversion (p = 0.002). No significant differences in static balance were observed between tDCS + FCE and control groups. The linear regression models showed an association towards significance between the percent changes in metatarsophalangeal joint flexor strength and the anteroposterior average sway velocity of the center of gravity in one-leg standing with eyes closed following tDCS + FCE (r2 = 0.286; p = 0.057). The exploratory analysis also showed that compared with FCE alone, the sham stimulation did not induce any placebo effects during FCE. CONCLUSION: Participating in 4 weeks of intervention using tDCS in combination with FCE effectively enhances toe flexor strength and foot-ankle sensory function.
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Terapia por Exercício , Equilíbrio Postural , Estimulação Transcraniana por Corrente Contínua , Humanos , Extremidade Inferior , Equilíbrio Postural/fisiologiaRESUMO
OBJECTIVES: To explore the effects of wearing compression garments on joint mechanics, soft tissue vibration and muscle activities during drop jumps. METHODS: Twelve healthy male athletes were recruited to execute drop jumps from heights of 30, 45 and 60 cm whilst wearing compression shorts (CS) and control shorts (CON). Sagittal plane kinematics, ground reaction forces, accelerations of the quadriceps femoris (QF), hamstrings (HM) and shoe heel-cup, and electromyography images of the rectus femoris (RF) and biceps femoris (BF) were collected. RESULTS: Compared with wearing CON, wearing CS significantly reduced the QF peak acceleration at 45 and 60 cm and the HM peak acceleration at 30 cm. Wearing CS significantly increased the damping coefficient for QF and HM at 60 cm compared with wearing CON. Moreover, the peak transmissibility when wearing CS was significantly lower than that when wearing CON for all soft tissue compartments and heights, except for QF at 30 cm. Wearing CS reduced the RF activity during the pre-, post-, and eccentric activations for all heights and concentric activations at 45 cm; it also reduced the BF activity during post- and eccentric activations at 30 and 60 cm, respectively. The hip and knee joint moments and power or jump height were unaffected by the garment type. CONCLUSION: Applying external compression can reduce soft tissue vibrations without compromising neuromuscular performance during strenuous physical activities that involve exposure to impact-induced vibrations.
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Músculo Esquelético , Vibração , Acelerometria , Fenômenos Biomecânicos , Eletromiografia , Exercício Físico , Humanos , Masculino , SapatosRESUMO
Objective: This study aims to explore the effects of 12-week gait retraining (GR) on plantar flexion torque, architecture, and behavior of the medial gastrocnemius (MG) during maximal voluntary isometric contraction (MVIC). Methods: Thirty healthy male rearfoot strikers were randomly assigned to the GR group (n = 15) and the control (CON) group (n = 15). The GR group was instructed to wear minimalist shoes and run with a forefoot strike pattern for the 12-week GR (3 times per week), whereas the CON group wore their own running shoes and ran with their original foot strike pattern. Participants were required to share screenshots of running tracks each time to ensure training supervision. The architecture and behavior of MG, as well as ankle torque data, were collected before and after the intervention. The architecture of MG, including fascicle length (FL), pennation angle, and muscle thickness, was obtained by measuring muscle morphology at rest using an ultrasound device. Ankle torque data during plantar flexion MVIC were obtained using a dynamometer, from which peak torque and early rate of torque development (RTD50) were calculated. The fascicle behavior of MG was simultaneously captured using an ultrasound device to calculate fascicle shortening, fascicle rotation, and maximal fascicle shortening velocity (Vmax). Results: After 12-week GR, 1) the RTD50 increased significantly in the GR group (p = 0.038), 2) normalized FL increased significantly in the GR group (p = 0.003), and 3) Vmax increased significantly in the GR group (p = 0.018). Conclusion: Compared to running training, GR significantly enhanced the rapid strength development capacity and contraction velocity of the MG. This indicates the potential of GR as a strategy to improve muscle function and mechanical efficiency, particularly in enhancing the ability of MG to generate and transmit force as well as the rapid contraction capability. Further research is necessary to explore the effects of GR on MG behavior during running in vivo.
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OBJECTIVES: In a variety of experimental models, propofol has been shown to protect the brain. It was hypothesized that a clinically achievable high dose of propofol would induce cerebral protective effects in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The authors investigated the effects of different target plasma concentrations of propofol on cerebral injury by measuring serum S-100ß protein and neuron-specific enolase (NSE) levels in patients undergoing single-valve replacement with CPB. DESIGN: A prospective, randomized study. SETTING: A university hospital. PARTICIPANTS: Forty-two patients undergoing single-valve replacement with CPB. INTERVENTIONS: Patients were randomly divided into 3 groups (n = 14 each). Each group received a target-controlled infusion of propofol with plasma concentrations of 1.8 µg/mL (low dose, Group-L), 2.4 µg/mL (medium dose, Group-M), or 3.2 µg/mL (high dose, Group-H). The propofol target concentrations were unchanged throughout the surgery. MEASUREMENTS AND MAIN RESULTS: In all 3 groups of patients, at all time points after CPB, the plasma S-100ß protein and NSE levels, which served as biochemical markers of brain damage, were significantly higher than the preoperative levels (p<0.05). Group-H showed significant decreases in S-100ß protein and NSE compared with Group-L (p< 0.05). CONCLUSION: In the range of commonly used clinical concentrations, administration of a high dose of propofol during CPB attenuated the biochemical markers of brain damage as compared with low-dose propofol anesthesia.
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Anestésicos Intravenosos/farmacologia , Procedimentos Cirúrgicos Cardíacos , Fatores de Crescimento Neural/sangue , Fosfopiruvato Hidratase/sangue , Propofol/farmacologia , Proteínas S100/sangue , Adulto , Ponte Cardiopulmonar , Depressão Química , Relação Dose-Resposta a Droga , Feminino , Implante de Prótese de Valva Cardíaca/métodos , Hemodinâmica/efeitos dos fármacos , Humanos , Hipnóticos e Sedativos , Masculino , Midazolam , Pessoa de Meia-Idade , Monitorização Intraoperatória , Subunidade beta da Proteína Ligante de Cálcio S100 , EsternotomiaRESUMO
BACKGROUND Vasovagal syncope is a loss of consciousness caused by decreased arterial pressure and cerebral blood flow. The characteristic features of vasovagal syncope include cardiovascular inhibition caused by neural reflexes, accompanied by vasodilation and bradycardia. To date, there is little literature to report several episodes of syncope under spinal anesthesia during the perioperative period for drainage of an anal abscess. The purpose of this article is to alert clinical practitioners to the early identification of the underlying causes of vasovagal syncope and to facilitate timely and effective management strategies. CASE REPORT We present the case of a 44-year-old man with a perianal abscess who was scheduled for an incision and drainage procedure for the abscess under spinal anesthesia. Preoperative assessment revealed no history of cardiac disease, neurological disorders, or drug allergies. During the perioperative period, the patient experienced 3 episodes of syncope: 1 episode during puncture of spinal anesthesia, and the others at 6.5 h and 8.5 h after the procedure. The patient was discharged 4 days later, and a 30-day postoperative follow-up showed good recovery, without any episodes of syncope. CONCLUSIONS We described a case of 3 episodes of vasovagal syncope occurring in a patient during the perioperative period of drainage of perianal abscess under spinal anesthesia. Pain may have been the main cause of vasovagal syncope in this patient. To avoid vasovagal syncope, it is best for anesthesiologists to choose the lateral position to perform spinal anesthesia and to provide good perioperative pain management for these patients.
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Raquianestesia , Doenças do Ânus , Síncope Vasovagal , Masculino , Humanos , Adulto , Síncope Vasovagal/etiologia , Raquianestesia/efeitos adversos , Abscesso/etiologia , Abscesso/cirurgia , Síncope , Drenagem/efeitos adversos , DorRESUMO
The purpose of this study was to investigate the differences in the morphological and viscoelastic properties of the Achilles tendon (AT) among different groups (rearfoot strikers vs. forefoot strikers vs. non-runners). Thirty healthy men were recruited, including habitual forefoot strike runners (n = 10), rearfoot strike runners (n = 10), and individuals with no running habits (n = 10). The AT morphological properties (cross-sectional area and length) were captured by using an ultrasound device. The real-time ultrasound video of displacement changes at the medial head of the gastrocnemius and the AT junction during maximal voluntary isometric contraction and the plantar flexion moment of the ankle was obtained simultaneously by connecting the ultrasound device and isokinetic dynamometer via an external synchronisation box. The results indicated that male runners who habitually forefoot strike exhibited significantly lower AT hysteresis than male non-runners (p < 0.05). Furthermore, a greater peak AT force during maximal voluntary contraction was observed in forefoot strike male runners compared to that in male individuals with no running habits (p < 0.05). However, foot strike patterns were not related to AT properties in recreational male runners (p > 0.05). The lower AT hysteresis in male FFS runners implied that long-term forefoot strike patterns could enhance male-specific AT's ability to store and release elastic energy efficiently during running, resulting in a more effective stretch-shortening cycle. The greater peak AT force in male FFS runners indicated a stronger Achilles tendon.
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PURPOSE: To explore the difference in the biomechanics of the lower extremity during alternating jump rope skipping (AJRS) under barefoot and shod conditions. METHODS: Fourteen experienced AJRS participants were randomly assigned to wear jump rope shoes or be barefoot (BF) during the AJRS at a self-selected speed. The Qualisys motion capture system and Kistler force platform were used to synchronously collect the ground reaction forces and trajectory data of the hip, knee, ankle, and metatarsophalangeal (MTP) joints. One-dimensional statistical parameter mapping was used to analyze the kinematics and kinetics of the lower extremity under both conditions using paired t-tests. RESULTS: Wearing shoes resulted in a significant decrease in the ROM (p < 0.001) and peak angular velocity (p < 0.001) of the MTP joint during the landing phase. In addition, the MTP joint power (p < 0.001) was significantly larger under shod condition at 92-100% of the landing phase. Moreover, wearing shoes reduced the peak loading rate (p = 0.002). CONCLUSION: The findings suggest that wearing shoes during AJRS could provide better propulsion during push-off by increasing the MTP plantarflexion joint power. In addition, our results emphasize the significance of the ankle and MTP joint by controlling the ankle and MTP joint angle.
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Venous thromboembolism (VTE) is a life-threatening postoperative complication of malignant tumors. We identified risk factors for postoperative VTE in patients undergoing radical resection of colorectal cancer (CRC) and constructed and validated a clinical prediction model. Clinical data of 982 patients undergoing radical resection of CRC from September 1, 2020, to March 31, 2022, in Ningxia Medical University General Hospital were analyzed retrospectively. Patients were randomly divided into training (n = 617) and validation groups (n = 264). Data included baseline characteristics, preoperative complications, examination results, and intraoperative and postoperative indicators. Logistic regression analysis was used to determine risk factors, build a predictive model, and draw a predictive nomogram (CRSPOT). Receiver operating characteristics (ROC) curve was used to calculate the area under the curve (AUC) for evaluating the model's predictive ability. Independent risk factors for postoperative VTE were as follows: postoperative hemoglobin of <10â g/L (odds ratio [OR] 0.413, 95% confidence interval [CI] 0.220-0.777), postoperative D-dimer of ≥3.5µg/mL (OR 2.156, 95% CI 1.145-4.061), BMI of ≥25â kg/m2 (OR 2.313, 95% CI 1.225-4.369), operation time of ≥4â h (OR 2.292, 95% CI 1.232-4.262), lower extremity varicose veins (OR 4.499, 95% CI 1.764-11.476), postoperative ileus (OR 5.760, 95% CI 2.031-16.337), and postoperative hypoxemia (OR 9.230, 95% CI 4.562-18.672). The nomogram's AUC was 0.826, demonstrating a reliable predictive ability. The CRSPOT nomogram reliably predicts postoperative VTE in patients undergoing radical resection of CRC, identifying high-risk patients early, allowing early implementation of antithrombotic strategies, and helping to reduce the incidence and mortality of postoperative VTE.
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Neoplasias Colorretais , Tromboembolia Venosa , Humanos , Nomogramas , Estudos Retrospectivos , Tromboembolia Venosa/epidemiologia , Prognóstico , Modelos Estatísticos , Fatores de Risco , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/complicaçõesRESUMO
As a crucial and vulnerable component of the lower extremities, the medial gastrocnemius-Achilles tendon unit (gMTU) plays a significant role in sport performance and injury prevention during long-distance running. However, how habitual foot strike patterns influence the morphology of the gMTU remains unclear. Therefore, this study aimed to explore the effects of two main foot strike patterns on the morphological and mechanical characteristics of the gMTU. Long-distance male runners with habitual forefoot (FFS group, n = 10) and rearfoot strike patterns (RFS group, n = 10) and male non-runners (NR group, n = 10) were recruited. A Terason uSmart 3300 ultrasonography system was used to image the medial gastrocnemius (MG) and Achilles tendon, Image J software to analyze the morphology, and a dynamometer to determine plantar flexion torque during maximal voluntary isometric contractions. The participants first performed a 5-minute warm up; then, the morphological measurements of MG and AT were recorded in a static condition; finally, the MVICs test was conducted to investigate the mechanical function of the gMTU. One-way ANOVA and nonparametric tests were used for data analysis. The significance level was set at a p value of <0.05. The muscle fascicle length (FL) (FFS: 67.3 ± 12.7, RFS: 62.5 ± 7.6, NRs: 55.9 ± 2.0, η2 = 0.187), normalized FL (FFS: 0.36 ± 0.48, RFS: 0.18 ± 0.03, NRs: 0.16 ± 0.01, η2 = 0.237), and pennation angle (PA) (FFS: 16.2 ± 1.9, RFS: 18.9 ± 2.8, NRs: 19.3 ± 2.4, η2 = 0.280) significantly differed between the groups. Specifically, the FL and normalized FL were longer in the FFS group than in the NR group (p < 0.05), while the PA was smaller in the FFS group than in the NR group (p < 0.05). Conclusion: Long-term running with a forefoot strike pattern could significantly affect the FL and PA of the MG. A forefoot strike pattern could lead to a longer FL and a smaller PA, indicating an FFS pattern could protect the MG from strain under repetitive high loads.
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Purpose: To determine the 90 percent effective dose (ED90) of intrathecal sufentanil combined with ropivacaine 2.5 mg for labor analgesia and observe its safety for parturients and neonates. Methods: We conducted a prospective, double-blind, biased coin up-and-down study. We injected a fixed 2.5 mg ropivacaine combined with a designated dose of sufentanil intrathecally to observe the labor analgesic effect. The initial dose of sufentanil was assigned 1.0 µg, and the remaining doses were assigned as per the biased coin up-and-down method. The criterion of successful response was defined as VAS ≤ 30 mm after intrathecal injection at 10 min. Safety was evaluated in terms of maternal and neonatal outcomes. Results: The ED90 dose of intrathecal sufentanil combined with ropivacaine 2.5 mg (0.1%, 2.5 mL) was 2.61 µg (95% CI, 2.44 to 2.70 µg) by isotonic regression. No respiratory depression, hypotension, or motor block was observed. Thirty-one (77.5%) parturients complained of pruritus, and 14 (35.0%) suffered nausea and vomiting. Three neonates reported a 1 min Apgar score of ≤7, and none reported a 5 min Apgar score of ≤7. Conclusion: The ED90 of intrathecal sufentanil combined with ropivacaine 2.5 mg for labor analgesia was 2.61 µg. The dose is safe for parturients and neonates.
RESUMO
BACKGROUND: Patients with end-stage liver disease have increased sensitivity to general anesthetics. In this study, we sought to quantify sensitivity to propofol as a function of the degree of liver disease, in a rat model of cirrhosis. METHODS: Liver disease was induced by carbon tetrachloride (CCl(4)) injections for 6, 9, or 12 weeks in 3 study groups. Control rats received saline injections on the same schedule as CCl(4)-injected rats. A second control (comparison) group was treated with phenobarbital for a week followed by 9 weeks of phenobarbital and 10% ethanol in drinking water. Liver function was assessed by liver function tests and pathologic scoring of liver histology. RESULTS: Progressively worse cirrhosis was associated with longer CCl(4) treatment by histologic criteria, by hypersplenism, liver to body weight ratios, and liver function tests. The major findings were that mild liver disease (either steatosis or fibrosis) was not associated with increased propofol sensitivity, but recovery times after propofol bolus and propofol infusion were significantly increased in rats with more severe liver fibrosis. CONCLUSION: Propofol sensitivity is not significantly affected in the setting of mild liver disease, similar to clinical observations, but end-stage liver disease (fibrosis) is associated with significantly prolonged time to recovery after propofol infusion. The progressive liver disease model used in these studies is useful for rigorously studying anesthetic sensitivity as a function of degree of hepatocellular-fibrotic liver disease.
Assuntos
Anestésicos Intravenosos/farmacologia , Cirrose Hepática Experimental/diagnóstico , Fígado/patologia , Propofol/farmacologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Tetracloreto de Carbono , Progressão da Doença , Fígado/metabolismo , Cirrose Hepática Experimental/sangue , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/patologia , Cirrose Hepática Experimental/fisiopatologia , Testes de Função Hepática , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Albumina Sérica/metabolismo , Índice de Gravidade de Doença , Fatores de TempoRESUMO
The morphological and mechanical properties (e.g., stiffness, stress, and force) of the Achilles tendon (AT) are generally associated with its tendinosis and ruptures, particularly amongst runners. Interest in potential approaches to reduce or prevent the risk of AT injuries has grown exponentially as tendon mechanics have been efficiently improving. The following review aims to discuss the effect of different types of exercise on the AT properties. In this review article, we review literature showing the possibility to influence the mechanical properties of the AT from the perspective of acute exercise and long-term training interventions, and we discuss the reasons for inconsistent results. Finally, we review the role of the habitual state in the AT properties. The findings of the included studies suggest that physical exercise could efficiently improve the AT mechanical properties. In particular, relatively long-term and low-intensity eccentric training may be a useful adjunct to enhance the mechanical loading of the AT.
RESUMO
The study aimed to evaluate the effect of forced-air warming blanket combined with conventional thermal insulation measures on inadvertent perioperative hypothermia (IPH) in elderly patients undergoing laparoscopic radical resection of colorectal cancer. A total of 70 elderly patients undergoing laparoscopic radical resection of colorectal cancer with general anesthesia were included, and divided into conventional warming treatment (CT) group or forced-air warming treatment (FT) group. In the FT group, based on the conventional warming strategy, patients received prewarming with the forced-air warming blanket (38°C) for ≥20 minutes before induction of anesthesia, and received this treatment continuously during operation. The core body temperature, recovery time from anesthesia, extubating time, and length of stay in the postanesthesia care unit were recorded. The incidence of IPH and postoperative shivering was observed. The incidence of IPH was significantly lower, and average minimum body temperature during the operation was significantly higher in the FT group than that in the CT group (5.7% vs. 22.8% and 36.23°C vs. 35.89°C, respectively). The intraoperative body temperature decreased less (0.32°C vs. 0.69°C), the recovery time from anesthesia was faster (12.8 minutes vs. 17.1 minutes), and the incidence of postoperative shivering was less (2.8% vs. 28.6%) in the FT group than the CT group. In elderly patients undergoing laparoscopic radical resection of colorectal cancer, use of forced-air warming blankets combined with conventional warming measures is more effective to maintain normal body temperature during the perioperative period and reduce the incidence of IPH.