In order to realize the quantitative assessment of muscle strength in hand function rehabilitation and then formulate scientific and effective rehabilitation training strategies, this paper constructs a multi-scale convolutional neural network (MSCNN) - convolutional block attention module (CBAM) - bidirectional long short-term memory network (BiLSTM) muscle strength prediction model to fully explore the spatial and temporal features of the data and simultaneously suppress useless features, and finally achieve the improvement of the accuracy of the muscle strength prediction model. To verify the effectiveness of the model proposed in this paper, the model in this paper is compared with traditional models such as support vector machine (SVM), random forest (RF), convolutional neural network (CNN), CNN - squeeze excitation network (SENet), MSCNN-CBAM and MSCNN-BiLSTM, and the effect of muscle strength prediction by each model is investigated when the hand force application changes from 40% of the maximum voluntary contraction force (MVC) to 60% of the MVC. The research results show that as the hand force application increases, the effect of the muscle strength prediction model becomes worse. Then the ablation experiment is used to analyze the influence degree of each module on the muscle strength prediction result, and it is found that the CBAM module plays a key role in the model. Therefore, by using the model in this article, the accuracy of muscle strength prediction can be effectively improved, and the characteristics and laws of hand muscle activities can be deeply understood, providing assistance for further exploring the mechanism of hand functions .
Neural Networks, Computer ; Humans ; Hand Strength/physiology* ; Support Vector Machine ; Muscle Strength/physiology* ; Hand/physiology* ; Convolutional Neural Networks

Reach-to-grasp movements require integrating information on both object location and grip type, but how these elements are planned and to what extent they interact remains unclear. We designed a new experimental paradigm in which monkeys sequentially received reach and grasp cues with delays, requiring them to retain and integrate both cues to grasp the goal object with appropriate hand gestures. Neural activity in the dorsal premotor cortex (PMd) revealed that reach and grasp were similarly represented yet not independent. Upon receiving the second cue, the PMd continued encoding the first, but over half of the neurons displayed incongruent modulations: enhanced, attenuated, or even reversed. Population-level analysis showed significant changes in encoding structure, forming distinct neural patterns. Leveraging canonical correlation analysis, we identified a shared subspace preserving the initial cue's encoding, contributed by both congruent and incongruent neurons. Together, these findings reveal a novel perspective on the interactive planning of reach and grasp within the PMd, providing insights into potential applications for brain-machine interfaces.
Animals ; Motor Cortex/physiology* ; Hand Strength/physiology* ; Macaca mulatta ; Psychomotor Performance/physiology* ; Neurons/physiology* ; Male ; Cues ; Movement/physiology* ; Gestures

Objective: To investigate the present situation of pelvic floor muscle strength, and to analyze the factors affecting pelvic floor muscle strength. Methods: The data of patients who were admitted into the general outpatient department of gynecology, Peking University People's Hospital from October 2021 to April 2022 were collected, and the patients who met the exclusion criteria were included in this cross sectional study. The patient's age, height, weight, education level, defecation way and defecation time, birth history, maximum newborn birth weight, occupational physical activity, sedentary time, menopause, family history and disease history were recorded by questionnaire. Morphological indexes such as waist circumference, abdomen circumference and hip circumference were measured with tape measure. Handgrip strength level was measured with grip strength instrument. After performing routine gynecological examinations, the pelvic floor muscle strength was evaluated by palpation with modified Oxford grading scale (MOS). MOS grade>3 was taken as normal group and ≤3 as decreased group. Binary logistic regression was used to investigate the related factors of deceased pelvic floor muscle strength. Results: A total of 929 patients were included in the study, and the average MOS grade was 2.8±1.2. By univariate analysis, birth history, menopausal time, defecation time, handgrip strength level, waist circumference and abdominal circumference were related to the decrease of pelvic floor muscle strength (all P<0.05). By binary logistic regression analysis, the level of handgrip strength (OR=0.913, 95%CI: 0.883-0.945; P<0.001) was correlated with normal pelvic floor muscle strength; waist circumference (OR=1.025, 95%CI: 1.005-1.046; P=0.016), birth history (OR=2.224, 95%CI: 1.570-3.149; P<0.001), sedentary time> 8 hours (OR=2.073, 95%CI: 1.198-3.587; P=0.009) were associated with the decrease of pelvic floor muscle strength. Conclusions: The level of handgrip strength is related to the normal pelvic floor muscle strength of females, while the waist circumference, birth history and sedentary time>8 hours are related to the decrease of pelvic floor muscle strength of females. In order to prevent the decrease of pelvic floor muscle strength, it is necessary to carry out relevant health education, enhance exercise, improve the overall strength level, reduce daily sedentary time, maintain symmetry, and carry out comprehensive overall intervention to improve pelvic floor muscle function.
Adult ; Female ; Humans ; Cross-Sectional Studies ; Gynecology ; Hand Strength ; Muscle Contraction/physiology* ; Muscle Strength/physiology* ; Outpatients ; Pelvic Floor/physiology*

This study aims to investigate the inhibitory effect of Pien Tze Huang(PZH) on enterovirus 71(EV71). To be speci-fic, chemiluminescence method was adopted to evaluate the toxicity of PZH to African green monkey kidney(Vero) cells and human rhabdomyosarcoma(RD) cells, and cytopathic effect(CPE) method to assess the inhibition on EV71-GFP reporter virus and EV71 C4 wild-type virus. The results showed that PZH had low cytotoxicity to Vero cells and RD cells, with the half-maximal cytotoxic concentration(CC_(50)) of about 0.691 3-0.879 2 mg·mL~(-1) for the two. In addition, PZH can effectively inhibit the replication of EV71 within the non-cytotoxic concentration range, and dose-dependently alleviate the cytopathic changes caused by virus infection, with the half-maximal effective concentration(EC_(50)) of 0.009 2-0.106 3 mg·mL~(-1). On the basis of the above results, the green fluorescent protein(GFP), indirect immunofluorescence assay(IFA), and median tissue culture infective dose(TCID_(50)) were employed to assess and verify the anti-EV71-GFP and anti-EV71 C4 activity of PZH. The results demonstrated that PZH can dose-dependently lower the expression of GFP by EV71-GFP and structural protein VP-1 by EV71 C4 and decrease the production of progeny infectious viruses. The EC_(50) of PZH for EV71-GFP and EV71 C4 was about 0.006 0-0.006 2 mg·mL~(-1) and 0.006 6-0.025 6 mg·mL~(-1), respectively. This study suggested that PZH may exert antiviral activity by acting on EV71 and interfering with the expression of VP-1. At the moment, there is still a lack of specific anti-EV71 drugs. This study proposed a new idea for the symptomatic treatment of EV71 infections such as hand-foot-mouth disease and verified an effective drug for the treatment of EV71 infections.
Animals ; Chlorocebus aethiops ; Drugs, Chinese Herbal/pharmacology* ; Enterovirus A, Human/physiology* ; Hand, Foot and Mouth Disease ; Vero Cells

Objective: To explore the relationship of sleep duration and insomnia with muscle mass, strength, and quality in Chinese adults. Methods: Based on the second resurvey of China Kadoorie Biobank (CKB) in 2013-2014, logistic regression models were used to analyze the correlation of sleep duration, insomnia, and its duration with low muscle mass, handgrip strength, and muscle quality. Results: The average sleep duration of the study population was (7.4±1.5) hours. Morbidities of short sleep duration (<6 hours), long sleep duration (≥9 hours), and insomnia were 9.3%,17.4%,and 29.9%,respectively. Compared with those who slept for 7- hours, those who slept for ≥9 hours were more likely to have low muscle mass, low handgrip strength,and low arm muscle quality (AMQ), and the OR (95%CI) of low appendicular skeletal muscle mass index (ASMI), low total skeletal muscle mass index (TSMI), low grip strength and low AMQ were 1.32 (1.18-1.48),1.26 (1.13-1.41), 1.33 (1.18-1.49) and 1.16 (1.03-1.30), respectively. Compared with participants without insomnia, insomnia patients were more likely to have low muscle mass,and the longer the duration of insomnia,the higher the risk (P for trend <0.001). Participants who reported <6 hours sleep duration and insomnia had a higher proportion of low ASMI and low TSMI,compared with those who slept for 7- hours and without insomnia, the OR (95%CI) were 1.26 (1.08-1.47) and 1.25 (1.07-1.46), respectively. Conclusions: Participants who reported ≥9 hours sleep duration were more likely to have low muscle mass,low handgrip strength,and low AMQ. Participants with insomnia had lower muscle mass, and the longer the duration of insomnia, the higher the proportion of low ASMI and low TSMI.
Adult ; China/epidemiology* ; Hand Strength ; Humans ; Muscles ; Sleep/physiology* ; Sleep Initiation and Maintenance Disorders/epidemiology*

BACKGROUND: There is little data on the association between the lower nutrition represented by serum albumin levels and related factors in a general population. The present study aimed to determine whether the albumin level positioned as some kind of biomarker with frailty measures, trace elements, and an inflammation marker. METHODS: In 2018, we performed an epidemiological survey in 1368 subjects who resided in Tanushimaru, Japan, in which we examined the blood chemistry including albumin, trace elements, hormone levels, and carotid ultrasonography. Albumin levels were categorized into 4 groups (G1 [3.2-3.9 mg/dL], G2 [4.0-4.3 mg/dL], G3 [4.4-4.6 mg/dL], and G4 [4.7-5.3 mg/dL]). The participants underwent measurements of handgrip strength and were tested by asking to walk 5 m. Their cognitive functions were evaluated by the mini-mental state examination (MMSE). RESULTS: Multiple stepwise regression analysis demonstrated that albumin levels were significantly and independently associated with age (inversely), systolic blood pressures, estimated glomerular filtration rate (eGFR), MMSE score, frailty measures (handgrip strength), an inflammation marker (high-sensitivity C-reactive protein), hormones (growth hormone (inversely) and insulin-like growth factor-1), and trace elements (calcium, magnesium, iron, and zinc), with a linear trend. CONCLUSIONS Lower albumin levels, even in the normal range, were found to be related factors of frailty measures, trace elements, and an inflammation marker in a general population.
Aged ; Albumins/metabolism* ; Biomarkers/blood* ; Cross-Sectional Studies ; Female ; Frailty/physiopathology* ; Hand Strength/physiology* ; Humans ; Inflammation/blood* ; Japan ; Male ; Trace Elements/blood*

BACKGROUND: The number of adults aged over 65 years is rapidly increasing in several Southeast Asian countries. Muscle mass decreases with age, leading to sarcopenia. The primary objective of this study was to determine whether differences exist in the body composition and physical strength, according to ethnicity, among community-dwelling Japanese and Thai older adults living in Chiang Mai Province, Thailand. METHODS: A survey was conducted in February and March 2019. Japanese and Thai adults aged ≥ 60 years living in Chiang Mai Province were recruited through community clubs. Participants completed a self-administered questionnaire that enabled collection of data on age, sex, educational background, marital status, annual income, current medical conditions, smoking and alcohol consumption, and exercise habits. Measurements were collected on height, weight, body composition, blood pressure, hand grip, and walking speed for 6 m. Body composition was measured using a standing-posture 8-electrode multifrequency bioimpedance analysis analyzer. Hand grip of each hand was measured with the patient in the standing position using a digital grip dynamometer. Multivariable logistic regression was used to determine factors associated with skeletal muscle mass index (SMI). RESULTS: Of the total 119 participants, 47 were Japanese (26 men, 21 women) and 72 were Thai (16 men, 56 women). The prevalence of a low SMI was 3/26 (12%), 1/21 (5%), 6/16 (38%), and 5/56 (9%) among Japanese men, Japanese women, Thai men, and Thai women, respectively. The prevalence of low muscle strength was 2/26 (8%), 2/21 (10%), 3/16 (19%), and 13/56 (23%) among Japanese men, Japanese women, Thai men, and Thai women, respectively. There were significant differences between ethnic groups in body mass index for both sexes, percentage body fat in women, SMI in men, and average grip strength in men. Ethnic group, sex, age, and body mass index were independent predictors of SMI. CONCLUSIONS Ethnicity had a clinically important effect on body composition and physical strength among older Japanese and Thai adults living in a similar environment.
Aged ; Aging/physiology* ; Asians/ethnology* ; Body Composition ; Body Mass Index ; Cross-Sectional Studies ; Electric Impedance ; Ethnicity ; Female ; Hand Strength ; Humans ; Independent Living ; Male ; Middle Aged ; Muscle Strength ; Thailand/ethnology* ; Walking Speed

Bipedalism (using only two legs for walking) and having the capability to use tools have long been considered characteristic features that differentiate human beings from animals. Being able to walk upright freed up human hands, allowing us to reach, grasp, carry food, make and use tools, which greatly increased the survivability of our ancestors. Hand actions not only involve muscles and joints to execute actions but also require computations in the brain to analyze the visual environment and select the appropriate action, as well as formulate the action before execution and correct it in real-time during execution. Here, we review the behavioral and brain imaging research of human hand actions from a perspective of cognitive neuroscience. The review includes the research contents and methods of visually-guided action, existing theories, current debates, new evidence of existing theories, and the applications of action research in robotics and artificial intelligence.
Brain ; diagnostic imaging ; physiology ; Hand ; Humans ; Neuroimaging ; Psychomotor Performance

OBJECTIVETo reveal the force mechanism for therapeutic effect of pushing manipulation with one-finger meditation.

METHODSA total of 15 participants were recruited in this study and assigned to an expert group, a skilled group and a novice group, with 5 participants in each group. Mechanical signals were collected from a biomechanical testing platform, and these data were further observed via similarity analysis and cluster analysis.

RESULTSComparing the force waveforms of manipulation revealed that the manipulation forces were similar between the expert group and the skilled group (P>0.05). The mean value of vertical force was 9.8 N, and 95% CI rang from 6.37 to 14.70 N, but there were significant differences compared with the novice group (P<0.05). The result of overall similarity coefficient cluster analysis showed that two kinds of manipulation forces curves were existed between the expert group and the skilled group.

CONCLUSIONPushing manipulation with one-finger meditation is a kind of light stimulation manipulation on the acupoint, and force characteristics of double waveforms continuously alternated during manual operation.

Acupuncture Points ; Biomechanical Phenomena ; physiology ; Clinical Competence ; Fingers ; physiology ; Hand Strength ; physiology ; Humans ; Individuality ; Massage ; education ; methods ; Medicine, Chinese Traditional ; methods ; Meditation ; methods ; Models, Theoretical ; Musculoskeletal Manipulations ; education ; methods ; standards

BACKGROUND: Hemoglobin concentration reportedly is positively associated with muscle strength, for example, handgrip strength. However, hemoglobin cannot repair muscle directly, but is beneficial only in a supportive role. Since hepatocyte growth factor (HGF) regulates muscle satellite cell production and differentiation, which is stimulated by organ injury, the supportive effect of hemoglobin should thus be stronger for participants with high HGF than for those with low HGF. However, the association between hemoglobin concentration and handgrip strength in relation to HGF levels remains unknown. METHODS: We conducted a cross-sectional study of 255 Japanese elderly men aged 60-69 years who participated in annual health check-ups in 2014-2015. The study population was categorized on the basis of a median value of HGF of 300.6 pg/mL. RESULTS: Among present study population, 128 participants showed low HGF. For participants with low HGF, hemoglobin concentration showed no significant association with handgrip strength (standardized parameter estimate (β) = 0.03, p = 0.767), but for those with high HGF, hemoglobin concentration was significantly positively associated with handgrip strength (β = 0.23, p = 0.014). CONCLUSIONS A significant positive association between hemoglobin level and handgrip strength was established for elderly Japanese men aged 60-69 years with high HGF but not for participants with low HGF. Our finding indicates that HGF levels could determine the relationship of hemoglobin concentration with handgrip strength in elderly Japanese men aged 60-69 years. This result can be expected to serve as an effective tool for the clarification of the roles played by HGF and hemoglobin concentration in maintenance of muscle strength.
Aged ; Cross-Sectional Studies ; Hand Strength ; physiology ; Hemoglobins ; metabolism ; Hepatocyte Growth Factor ; genetics ; metabolism ; Humans ; Japan ; Male ; Middle Aged