A Plasmon Resonance Enhanced Photo-Electrode to Promote NH3 Yield in Sustainable N2 Conversion.

A key challenge for electrochemical nitrogen reduction reactions (NRR) is the difficulty for conventional catalysts to achieve high currents at low H* coverage to produce appreciable NH3 . Herein, we specially designed an Au nanoparticle-embedded ZnSe photo-electrode to solve the problem. As-designed photo-electrode achieves excellent NRR performance with a high NH3 yield (12.2 µg cm-2 h-1 ) and Faradaic efficiency (27.3 %). Our work reveals that the unique plasmon resonance effect of embedded Au nanoparticles plays a key role in increasing catalytic current when the H* coverage is decreased. Moreover, we successfully established a correlation between H* coverage and NRR performance based on theoretical calculations and experimental observations. This work paves the path for the future design of catalytic materials to overcome the selectivity and yield challenge of sustainable NH3 production.

Insulin for hyperglycemia prevention and management during postgastrectomy nutrition support in gastric cancer: Reduced complications in a retrospective cohort study in China.

BACKGROUND AND OBJECTIVES: To evaluate the effectiveness of insulin addition to the total nutrition admixture (TNA) for glycemic control among patients with gastric cancer (GC) receiving supplementary parenteral nutrition (SPN) after gastrectomy. METHODS AND STUDY DESIGN: A retrospective cohort study was conducted among 208 noncritical ill patients who underwent gastrectomy for GC from 2017 to 2019 at a tertiary teaching hospital in Lanzhou, China. All the included patients received individualized SPN and enteral nutrition treatment after gastrectomy. The patients were randomly divided into insulin and noninsulin groups based on the TNA composition. Blood glucose (BG) measurements, glycemic fluctuation, and hypoglycemia incidence during SPN were compared between the two groups. The postoperative comprehensive complications index (CI) and infections were compared according to insulin regimen and postoperative glycemic status. RESULTS: The mean BG was significantly lower and fluctuated less in the insulin group than in the noninsulin group (p<0.05). One unit of insulin per 6 g of parenteral nutrition glucose addition to TNA did not increase hypoglycemia incidence (p>0.05). Comparing CI and the infection rate, no significance was observed between the insulin and noninsulin groups, but a higher postoperative CI was observed in patients with hyperglycemia than in euglycemic patients (p<0.05). CONCLUSIONS: Appropriate insulin addition to TNA has an overall positive effect on glycemic management in patients with noncritical GC who received SPN after gastrectomy. Postoperative glycemic status was associated with the incidence of relevant complications. Further research is needed for conclusive recommendations.

Individualized Treatment and Palliative Care for A 90-Year-Old Patient with Primary Gastric Diffuse Large-B Cell Lymphoma: 4 Year Follow-up and Inspiration.

A 90-year-old man was diagnosed with primary gastric diffuse large B-cell lymphoma (PGDLBL) by PET/CT examination, gastroscopy, biopsy and histopathological analysis at a regular physical check in April, 2016. The patient received R-CO chemotherapy (rituximab, cyclophosphamide, and vincristine) and radiotherapy subsequently, with enteral nutritional treatment through 3-cavity nasogastric tube due to development of pyloric obstruction. To satisfy patient's strong desire of eating by himself, we performed surgery of exploratory laparotomy and Roux-en-Y gastric bypass (RGB) to relieve pylorus obstruction. Postoperatively, the patient resumed oral feeding, supplemented by nasogastric tube feeding at 1350 - 1550 Kcal daily. He is now 94 years old with fairly well nutrition and normal communication. The outcome of 4 year follow-up suggests that nutritional treatment and palliative medicine are important for improving prognosis and life-quality of very elderly patients with end-stage tumors apart from the effective chemotherapy, radiotherapy, and surgery.

A novel benzothiadiazole-based and NIR-emissive fluorescent sensor for detection of Hg2+ and its application in living cell and zebrafish imaging.

The development of a novel near-infrared (NIR) probe for the detection of toxic Hg2+ in organisms with high selectivity and sensitivity is of great interest but remains a great challenge. Hence, in this work, a new NIR fluorescence enhanced sensor (TBBA), which contains a D-A structure as the NIR fluorophore and rhodanine-3-acetic acid as the receptor, has been developed for the detection of Hg2+ with high selectivity, sensitivity, low limit of detection (13.10 nM) and good binding constant (2.37 × 104 M-1). The mechanism of TBBA response to Hg2+ was further proved by 1H NMR titration, HRMS, and theoretical calculations. Furthermore, TBBA is applied as a fluorescent probe for imaging living cells and zebrafish, indicating that it can be potentially applied for Hg2+ sensing in both environmental and biology fields.

Evaluation of tremor interference with control of voluntary reaching movements in patients with Parkinson's disease.

BACKGROUND: A large population of patients with Parkinson's disease (PD) displays the symptom of resting tremor. However, the extent that resting tremor may affect the performance of movement control has not been evaluated specifically. This study aims at establishing methods to quantitatively evaluate motor performance in PD patients with tremor, and at analyzing the interfering effects of tremor on control of reaching movements. METHODS: Ten PD patients with tremor and Ten healthy control subjects were recruited to participate in this study. All patients and healthy control subjects performed point-to-point reaching movements with their tremor affected arm or preferred arm. We verified that a smoothing model of minimum-jerk trajectory (MJT) can be used to extract voluntary movement trajectory from tremor-corrupted movement trajectory in the reaching tasks by the patients. Performance indices of reaction time (RT) and movement time (MT) of reaching movements by the PD subjects with tremor were evaluated using MJT trajectories. Differences of RT and MT between the recorded trajectories and MJT in PD and control subjects were calculated to investigate the extent that tremor may affect their motor performance. Linear mixed-effects model was used to identify the contributions of tremor, bradykinesia and rigidity to the performance indices of RT and MT based on UPDRS scores. The power spectrum densities (PSD) of tremor were also evaluated using hand velocities to represent tremor intensity and to analyze their correlations with RT and MT. RESULTS: The MJT model demonstrated good fit to recorded trajectory with a more consistent estimation of motor performance for both PD and control subjects. The RT and MT of patients were found to be 43.4 and 79.5% longer respectively than those of healthy control subjects. Analysis of the linear mixed-effects model was not able to reveal that tremor, bradykinesia and rigidity each had a significant contribution to RT or MT in PD patients with tremor. However, the PSD of tremor was found to correlate significantly to RT, but not to MT, in both linear regression and linear mixed-effects model. CONCLUSIONS: The minimum-jerk trajectory and power spectrum densities are effective quantitative tools for evaluating motor performance for PD patients with tremor. Resting tremor is one of the factors prolonging the initiation of voluntary reaching movement in these patients.

Mesh reinforcement for the prevention of incisional hernia formation: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: European Hernia Society guidelines suggested that the evidence of mesh augmentation for the prevention of incisional hernia (IH) was weak. In addition, previous systematic reviews seldom focused on quality of life and cost-effectiveness related to mesh placement. Therefore, an updated meta-analysis was performed to clarify quality of life, cost-effectiveness, the safety, and effectiveness of mesh reinforcement in preventing the incidence of IH. METHODS: Embase, Pubmed, and the Cochrane library were searched from the inception to May 2016 without language limitation for randomized controlled trials (RCTs) which explored mesh reinforcement for the prevention of IH in patients undergoing abdominal surgeries. RESULTS: Twelve RCTs totaling 1661 patients (958 in mesh, 703 in nonmesh) were included in our study. Compared with nonmesh, mesh reinforcement can effectively decrease the incidence of IH (relative risk: 0.19; 95% CI: 0.09-0.42). Besides, mesh placement was associated with improved quality of life, a higher rate of seroma (relative risk: 1.64; 95% CI: 1.13-2.37), and longer operating time (mean difference: 17.62; 95% CI: 1.44-33.80). No difference can be found between both groups in postoperative overall morbidity, systemic postoperative morbidity, wound-related morbidity, surgical site infection, hematoma, wound disruption, postoperative mortality, and length of hospital stay. CONCLUSIONS: Prophylactic mesh reinforcement may be effective and safe to prevent the formation of IH after abdominal surgery, without impairing quality of life. Thus, preventive mesh should be routinely recommended in high-risk patients.

Inhibition of Parkinsonian tremor with cutaneous afferent evoked by transcutaneous electrical nerve stimulation.

BACKGROUND: Recent study suggests that tremor signals are transmitted by way of multi-synaptic corticospinal pathway. Neurophysiological studies have also demonstrated that cutaneous afferents exert potent inhibition to descending motor commands by way of spinal interneurons. We hypothesize in this study that cutaneous afferents could also affect the transmission of tremor signals, thus, inhibit tremor in patients with PD. METHODS: We tested this hypothesis by activating cutaneous afferents in the dorsal hand skin innervated by superficial radial nerve using transcutaneous electrical nerve stimulation (TENS). Eight patients with PD having tremor dominant symptom were recruited to participate in this study using a consistent experimental protocol for tremor inhibition. Resting tremor and electromyogram (EMG) of muscles in the upper extremity of these subjects with PD were recorded, while surface stimulation was applied to the dorsal skin of the hand. Fifteen seconds of data were recorded for 5 s prior to, during and post stimulation. Power spectrum densities (PSDs) of tremor and EMG signals were computed for each data segment. The peak values of PSDs in three data segments were compared to detect evidence of tremor inhibition. RESULTS: At stimulation intensity from 1.5 to 1.75 times of radiating sensation threshold, apparent suppressions of tremor at wrist, forearm and upper arm and in the EMGs were observed immediately at the onset of stimulation. After termination of stimulation, tremor and rhythmic EMG bursts reemerged gradually. Statistical analysis of peak spectral amplitudes showed a significant difference in joint tremors and EMGs during and prior to stimulation in all 8 subjects with PD. The average percentage of suppression was 61.56% in tremor across all joints of all subjects, and 47.97% in EMG of all muscles. The suppression appeared to occur mainly in distal joints and muscles. There was a slight, but inconsistent effect on tremor frequency in the 8 patients with PD tested. CONCLUSIONS: Our results provide direct evidence that tremor in the upper extremity of patients with PD can be inhibited to a large extent with evoked cutaneous reflexes via surface stimulation of the dorsal hand skin area innervated by the superficial radial nerve.

Detection of Circulating Tumor Cells by Fluorescent Immunohistochemistry in Patients with Esophageal Squamous Cell Carcinoma: Potential Clinical Applications.

BACKGROUND Circulating tumor cells (CTCs) are tumor cells that leave the primary tumor site and enter the bloodstream, where they can spread to other organs; they are very important in the diagnosis, treatment, and prognosis of malignant tumors. However, few studies have investigated CTCs in esophageal squamous cell carcinoma (ESCC). The aim of this study was to investigate the CTCs in blood of ESCC patients and its potential relevance to clinicopathological features and prognosis. MATERIAL AND METHODS CTCs were acquired by a negative enrichment method that used magnetic activated cell sorting (MACSTM). Fluorescent immunohistochemistry (IHC) was used to identify the CTCs. Then, the positive CTC patients with ESCC were analyzed, after which the relationship between CTCs and clinicopathologic features was evaluated. RESULTS In the present study, 62 out of 140 (44.3%) patients with ESCC were positive for CTCs. The positive rate of CTCs was significantly related with stage of ESCC patients (P=0.013). However, there was no relationship between CTC status and age, sex, smoking tumor history, tumor location, differentiation of tumor, lymphatic invasion, or lymph venous invasion (P>0.05). Kaplan-Meier analysis showed that patients positive for CTCs had significantly shorter survival time than patients negative for CTCs. Multivariate analysis demonstrated that stage and CTC status were significant prognostic factors for patients with ESCC. CONCLUSIONS CTCs positivity is an independent prognostic biomarker that indicates a worse prognosis for patients with ESCC.

Simulated microgravity-induced mitochondrial dysfunction in rat cerebral arteries.

Exposure to microgravity results in cardiovascular deconditioning, and cerebrovascular oxidative stress injury has been suggested to occur. To elucidate the mechanism for this condition, we investigated whether simulated microgravity induces mitochondrial dysfunction in rat arteries. Four-week hindlimb unweighting (HU) was used to simulate microgravity in rats. Mitochondrial reactive oxygen species (ROS), mitochondrial membrane potential (Δψm), mitochondrial permeability transition pore (mPTP) opening, mitochondrial respiratory control ratio (RCR), MnSOD/GPx activity and expression, and mitochondrial malondialdehyde (MDA) were examined in rat cerebral and mesenteric VSMCs. Compared with the control rats, mitochondrial ROS levels, mPTP opening, and MDA content increased significantly (P<0.001, P<0.01, and P<0.01, respectively), Δψm, RCR, MnSOD/GPx activity (P<0.001 for Δψm and RCR; P<0.05 for MnSOD; and P<0.001 for GPx activity) and protein abundance of mitochondrial MnSOD/GPx-1 decreased (P<0.001 for MnSOD and GPx-1) in HU rat cerebral but not mesenteric arteries. Chronic treatment with NADPH oxidase inhibitor apocynin and mitochondria-targeted antioxidant mitoTempol promoted recovery of mitochondrial function in HU rat cerebral arteries, but exerted no effects on HU rat mesenteric arteries. Therefore, simulated microgravity resulted in cerebrovascular mitochondrial dysfunction, and crosstalk between NADPH oxidase and mitochondria participated in the process.

Contribution of inter-muscular synchronization in the modulation of tremor intensity in Parkinson's disease.

BACKGROUND: Involuntary central oscillations at single and double tremor frequencies drive the peripheral neuromechanical system of muscles and joints to cause tremor in Parkinson's disease (PD). The central signal of double tremor frequency was found to correlate more directly to individual muscle EMGs (Timmermann et al. 2003). This study is aimed at investigating what central components of oscillation contribute to inter-muscular synchronization in a group of upper extremity muscles during tremor in PD patients. METHODS: 11 idiopathic, tremor dominant PD subjects participated in this study. Joint kinematics during tremor in the upper extremity was recorded along with EMGs of six upper arm muscles using a novel experimental apparatus. The apparatus provided support for the upper extremity on a horizontal surface with reduced friction, so that resting tremor in the arm can be recorded with a MotionMonitor II system. In each subject, the frequencies of rhythmic firings in upper arm muscles were determined using spectral analysis. Paired and pool-averaged coherence analyses of EMGs for the group of muscles were performed to correlate the level of inter-muscular synchronization to tremor amplitudes at shoulder and elbow. The phase shift between synchronized antagonistic muscle pairs was calculated to aid coherence analysis in the muscle pool. RESULTS: Recorded EMG revealed that rhythmic firings were present in most recorded muscles, which were either synchronized to form phase-locked bursting cycles at a subject specific frequency, or unsynchronized with a random phase distribution. Paired coherence showed a stronger synchronization among a subset of recorded arm muscles at tremor frequency than that at double tremor frequency. Furthermore, the number of synchronized muscles in the arm was positively correlated to tremor amplitudes at elbow and shoulder. Pool-averaged coherence at tremor frequency also showed a better correlation with the amplitude of resting tremor than that of double tremor frequency, indicating that the neuromechanical coupling in peripheral neuromuscular system was stronger at tremor frequency. CONCLUSIONS: Both paired and pool-averaged coherences are more consistent indexes to correlate to tremor intensity in a group of upper extremity muscles of PD patients. The central drive at tremor frequency contributes mainly to synchronize peripheral muscles in the modulation of tremor intensity.

Experimental and Numerical Investigations on Thermal-Hydraulic Performance of Three-Dimensional Overall Jagged Internal Finned Tubes.

To satisfy the demand for efficient heat transfer, a novel three-dimensional overall jagged internal finned tube (3D-OJIFT) was fabricated, using the rolling-ploughing/extruding method. The thermal performance of the 3D-OJIFT were studied and compared in experiments and three-dimensional numerical simulations. The RNG k-ε turbulence model is well verified with the experimental results. By analyzing the distributions of velocity, temperature, and turbulence kinetic energy, it was found that the 3D-OJIFT destroyed the development of the velocity and thermal boundary layers, increased the turbulence disturbance, and reduced the temperature gradient, thus improving the heat transfer. The influences of the jagged height and jagged spiral angle of the 3D-OJIFT are discussed. The Nu and f increased as the jagged height of the 3D-OJIFT increased. The Nusselt number of the 3D-OJIFT was 1.67-2.04 times the value for the smooth tube. In addition, the comprehensive heat transfer performance of the 3D-OJIFT improved after increasing the jagged spiral angle. Compared with conventional internal helical-finned tubes and other reinforcement structures reported in the literature, the 3D-OJIFT demonstrated better comprehensive heat transfer performance. Finally, empirical correlations of the 3D-OJIFT were obtained.

Closed-Loop Force Control by Biorealistic Hand Prosthesis with Visual and Tactile Sensory Feedback.

The ability of a novel biorealistic hand prosthesis for grasp force control reveals improved neural compatibility between the human-prosthetic interaction. The primary purpose here was to validate a virtual training platform for amputee subjects and evaluate the respective roles of visual and tactile information in fundamental force control tasks. We developed a digital twin of tendon-driven prosthetic hand in the MuJoCo environment. Biorealistic controllers emulated a pair of antagonistic muscles controlling the index finger of the virtual hand by surface electromyographic (sEMG) signals from amputees' residual forearm muscles. Grasp force information was transmitted to amputees through evoked tactile sensation (ETS) feedback. Six forearm amputees participated in force tracking and holding tasks under different feedback conditions or using their intact hands. Test results showed that visual feedback played a predominant role than ETS feedback in force tracking and holding tasks. However, in the absence of visual feedback during the force holding task, ETS feedback significantly enhanced motor performance compared to feedforward control alone. Thus, ETS feedback still supplied reliable sensory information to facilitate amputee's ability of stable grasp force control. The effects of tactile and visual feedback on force control were subject-specific when both types of feedback were provided simultaneously. Amputees were able to integrate visual and tactile information to the biorealistic controllers and achieve a good sensorimotor performance in grasp force regulation. The virtual platform may provide a training paradigm for amputees to adapt the biorealistic hand controller and ETS feedback optimally.

A hybrid sensory feedback system for thermal nociceptive warning and protection in prosthetic hand.

Background: Advanced prosthetic hands may embed nanosensors and microelectronics in their cosmetic skin. Heat influx may cause damage to these delicate structures. Protecting the integrity of the prosthetic hand becomes critical and necessary to ensure sustainable function. This study aims to mimic the sensorimotor control strategy of the human hand in perceiving nociceptive stimuli and triggering self-protective mechanisms and to investigate how similar neuromorphic mechanisms implemented in prosthetic hand can allow amputees to both volitionally release a hot object upon a nociceptive warning and achieve reinforced release via a bionic withdrawal reflex. Methods: A steady-state temperature prediction algorithm was proposed to shorten the long response time of a thermosensitive temperature sensor. A hybrid sensory strategy for transmitting force and a nociceptive temperature warning using transcutaneous electrical nerve stimulation based on evoked tactile sensations was designed to reconstruct the nociceptive sensory loop for amputees. A bionic withdrawal reflex using neuromorphic muscle control technology was used so that the prosthetic hand reflexively opened when a harmful temperature was detected. Four able-bodied subjects and two forearm amputees randomly grasped a tube at the different temperatures based on these strategies. Results: The average prediction error of temperature prediction algorithm was 8.30 ± 6.00%. The average success rate of six subjects in perceiving force and nociceptive temperature warnings was 86.90 and 94.30%, respectively. Under the reinforcement control mode in Test 2, the median reaction time of all subjects was 1.39 s, which was significantly faster than the median reaction time of 1.93 s in Test 1, in which two able-bodied subjects and two amputees participated. Results demonstrated the effectiveness of the integration of nociceptive sensory strategy and withdrawal reflex control strategy in a closed loop and also showed that amputees restored the warning of nociceptive sensation while also being able to withdraw from thermal danger through both voluntary and reflexive protection. Conclusion: This study demonstrated that it is feasible to restore the sensorimotor ability of amputees to warn and react against thermal nociceptive stimuli. Results further showed that the voluntary release and withdrawal reflex can work together to reinforce heat protection. Nevertheless, fusing voluntary and reflex functions for prosthetic performance in activities of daily living awaits a more cogent strategy in sensorimotor control.

Somatotopically Evoked Tactile Sensation via Transcutaneous Electrical Nerve Stimulation Improves Prosthetic Sensorimotor Performance.

Sensory feedback provides critical interactive information for the effective use of hand prostheses. Non-invasive neural interfaces allow convenient access to the sensory system, but they communicate a limited amount of sensory information. This study examined a novel approach that leverages a direct and natural sensory afferent pathway, and enables an evoked tactile sensation (ETS) of multiple digits in the projected finger map (PFM) of participants with forearm amputation non-invasively. A bidirectional prosthetic interface was constructed by integrating the non-invasive ETS-based feedback system into a commercial prosthetic hand. The pressure information of five fingers was encoded linearly by the pulse width modulation range of the buzz sensation. We showed that simultaneous perception of multiple digits allowed participants with forearm amputation to identify object length and compliance by using information about contact patterns and force intensity. The ETS enhanced the grasp-and-transport performance of participants with and without prior experience of prosthetic use. The functional test of transport-and-identification further revealed improved execution in classifying object size and compliance using ETS-based feedback. Results demonstrated that the ETS is capable of communicating somatotopically compatible information to participants efficiently, and improves sensory discrimination and closed-loop prosthetic control. This non-invasive sensory interface may establish a viable way to restore sensory ability for prosthetic users who experience the phenomenon of PFM.

Effects of acute sacral neuromodulation on bladder reflex in complete spinal cord injury rats.

BACKGROUND: Neurogenic bladder associated with spinal cord injury (SCI) often results in serious disruption of lower urinary tract function. Compared to conventional therapies, sacral neuromodulation (SNM) may offer an alternative, non-destructive treatment for SCI patients with bladder dysfunction. Understanding bladder reflex changes following SCI and the effects of SNM may yield new insights for innovative use of this promising technique. Using a SCI rat model developed in this study, we investigated: 1) the bladder responses with different grades of bladder filling in intact and SCI rats; and 2) the effects of acute SNM on bladder reflex responses in SCI rats. METHODS: An SCI rat model with overactive bladder was developed and evaluated in this study to examine the effects of acute SNM on bladder reflex in complete SCI rats. Twelve adult female Sprague-Dawley rats were divided into three groups; group I: spinally intact rats (N = 4), group II: transected (T9-T10) rats (N = 4), i.e., SCI rats, and group III: SCI rats with SNM treatment (N = 4). All rats were anesthetized and set up for continuous saline infusion. Cystometric parameters, including contraction period, contraction duration, bladder peak pressure, and number of uninhibited contractions, were analyzed and compared between groups and between conditions with and without SNM treatment for SCI rats. RESULTS: In the intact rats, the frequency of bladder contraction was dependent upon the rate of bladder filling, while the spinal transected rats exhibited large fluctuation and demonstrated different patterns in response to saline infusion. Moreover, the bladder in SCI rats demonstrated an increased contraction period and a decreased contraction strength compared to the intact rats (all p < 0.05). In SCI rats under acute SNM treatment, bladder contraction period and duration tended to become longer, and the bladder peak pressure was decreased. The accumulating evidence indicated that acute SNM had inhibiting effects for bladder overactivity following SCI. CONCLUSION: The spinal rat model developed in this study was suitable to investigate the effect of sacral neural stimulation on micturition reflex. The results of present study demonstrated that the micturition reflex can be modulated by sacral neural stimulation.

Precision Control of Fingertip Force by a Biorealistic Hand with a Pair of Neuromorphic Muscles.

In this paper, the ability of precision control of fingertip forces was investigated in an antagonistic cable-driven prosthetic hand with neuromorphic twin of muscles. Surface electromyography (sEMG) signals collected from able-bodied subjects' forearm were processed and used as alpha motor commands to drive the neuromorphic muscle models. A pair of antagonistic muscles were cascaded by two servo motors to control the index finger. Force control performance was tested by pressing a spring with a fixed stiffness using the fingertip, where forces with varying target levels were regulated with visual feedback. Two able-bodied subjects performed the precision force control task with the prosthetic index finger by sEMG signals and the intact hand. One subject was tested with force level changes of 0.1N, and another subject with force level changes of 0.2N. The ability of force regulation by the prosthetic finger was compared to that of the intact finger. Results showed that the overall root-mean-squares (RMS) error of the prosthetic finger was low, although significantly higher than the intact finger, 75% higher in subject 1 and 57% in subject 2. However, the correlation coefficient between the forces of prosthetic finger and intact finger was high, 75% for subject 1 and 84% for subject 2, respectively. This preliminary study is encouraging, illustrating the feasibility of accurate and stable control of different levels of fingertip forces by the prosthetic finger, which is comparable to that of the intact finger. This capability may allow the prosthetic hand for fine manipulation tasks, such as grasping brittle objects, or response to object slip during grasp.Clinical Relevance-This work attempts to restore the ability of a prosthetic hand for precision fingertip force control that may enrich the functionality for users in activities of daily living.

Predictive Warning of Nociceptive Temperature during Prosthetic Hand Prehension.

Grasping hot objects may be harmful, and a warning of nociceptive temperature should be provided to prevent prosthetic hands from damage. This study developed a fast algorithm to predict the steady state temperature of grasped objects based on a thermoresistant sensor, and verified a bi-state sensory encoding strategy to inform either contact force or nociceptive temperature at prosthetic finger. Below the threshold, a buzz percept was used to encode fingertip force, and above the threshold, a tingling pain sensation was induced to warn harmful temperature. This sensory encoding mechanism was tested in one able-bodied subject with a psychophysical experimental paradigm. Results indicated that fast identification of the steady state temperature could be achieved in 0.75±0.00 s with an error of 8.3±6.0%. The subject was able to recognize whether the object temperature was above or below the threshold of nociceptive temperature with an average success rate of 98.2% and 97.0%, respectively. The action to release the tube could be executed in 0.80±0.32 s. The reaction time of successful identification and execution was 1.55 ± 0.32 s. The probability that a release reaction was triggered at the threshold of 60.0°C was calculated with tube temperatures varying from 30.0°C to 80.0°C. The 50% percentile point on the fitted stimulus-response curve corresponded to a temperature of 59.5°C, nearly identical to the internally set threshold. The psychophysical behavior test verified the sensory function to recognize and notify unsafe temperatures in real time.Clinical Relevance-The method of identifying and alerting nociceptive temperatures may restore the sensory ability of amputees to avoid potential damage of grasping hot objects with a prosthetic hand in activities of daily life.

Fusion of dual modalities of non-invasive sensory feedback for object profiling with prosthetic hands.

Introduction: Either non-invasive somatotopic or substitute sensory feedback is capable of conveying a single modality of sensory information from prosthetic hands to amputees. However, the neurocognitive ability of amputees to integrate multi-modality sensory information for functional discrimination is unclear. The purpose of this study was to assess the fusion of non-invasive somatotopic tactile and substitute aperture feedbacks for profile perception of multiple physical features during grasping objects. Methods: Two left transradial amputees with somatotopic evoked tactile sensation (ETS) of five fingers participated in the study. The tactile information of prosthetic hand was provided to amputees by the ETS feedback elicited on the stump projected finger map. Hand aperture information was conveyed to amputees with substitute electrotactile stimulation on the forearm or upper arm. Two types of sensory feedback were integrated to a commercial prosthetic hand. The efficacy of somatotopic ETS feedback on object length identification task was assessed with or without substitute aperture stimulation. The object size identification task was utilized to assess how ETS stimulation at the stump may affect aperture perception with stimulation on the ipsilateral upper arm or forearm. Finally, the task of identifying combined length and size was conducted to evaluate the ability of amputees to integrate the dual modalities of sensory feedback for perceiving profile features. Results: The study revealed that amputee subjects can effectively integrate the ETS feedback with electrotactile substitutive feedback for object profile discrimination. Specifically, ETS was robust to provide object length information with electrotactile stimulation at either the forearm or upper arm. However, electrotactile stimulation at the upper arm for aperture perception was less susceptible to the interference of ETS stimulation than at the forearm. Discussion: Amputee subjects are able to combine somatotopic ETS and aperture feedbacks for identifying multi-dimensional features in object profiling. The two sensory streams of information can be fused effectively without mutual interference for functional discrimination.

Frequency of metastases within the hypothalamic-pituitary area and the associated high-risk factors in patients with brain metastases.

Objective: Brain radiotherapy often results in impairment of hypothalamic-pituitary (HT-P) function, which in turn causes secretory dysfunction of related hormones. In this paper, the frequency of metastasis in the HT-P area and its high-risk factors in patients with brain metastasis were retrospectively analyzed, and thus provide experimental evidence for protecting HT-P area during whole brain radiotherapy (WBRT). Methods: A retrospective analysis was performed on the data of patients with brain metastasis diagnosed by cranial magnetic resonance imaging (MRI) at the First Hospital of Lanzhou University from 2017 to 2020. The anatomical positions of the hypothalamus and pituitary were delineated, followed by their expansion by 5 mm outwards, respectively, in the three-dimensional direction, and the hypothalamus +5 mm and pituitary +5 mm were obtained as the avoidance area, in which the frequency of brain metastasis was evaluated. Univariate and multivariate logistic regression models were used to analyze the high risk factors of brain metastasis in HT-P area. Results: A total of 3,375 brain metastatic lesions from 411 patients were included in the analysis. The rates of brain metastasis in the hypothalamus +5 mm and pituitary +5 mm in the whole group of cases were 2.9% (12/411) and 1.5% (6/411) respectively; the frequency of lesions was 0.4% (13/3375) and 0.2% (6/3375) respectively. Univariate and multivariate analyses showed that the number of brain metastases (OR = 14.946; 95% CI = 4.071-54.880; p < 0.001), and the occurrence of brain metastasis in the pituitary (OR = 13.331; 95% CI = 1.511-117.620; p = 0.020) were related to brain metastasis in the hypothalamus, and that the only relevant factor for brain metastasis in the pituitary was the occurrence of that in the hypothalamus (OR = 0.069; 95% CI = 0.010-0.461; p = 0.006). There was no correlation between tumor pathological types, the maximum diameter, the total volume of brain metastatic lesions and the risk of brain metastasis in hypothalamus and pituitary. Conclusion: The frequency of brain metastasis in the HT-P area is extremely low. The risk of brain metastases in the hypothalamus is correlated with their number. The larger the number of metastatic lesions, the higher the frequency of brain metastasis. Protection of the HT-P area during WBRT may be unlikely to compromise the tumor recurrence rate for patients with a relatively small number of brain metastases.

Prognostic value of extrahepatic metastasis on colon cancer with liver metastasis: a retrospective cohort study.

Introduction: The occurrence of metastasis is a threat to patients with colon cancer (CC), and the liver is the most common metastasis organ. However, the role of the extrahepatic organs in patients with liver metastasis (LM) has not been distinctly demonstrated. Therefore, this research aimed to explore the prognostic value of extrahepatic metastases (EHMs). Methods: In this retrospective study, a total of 13,662 colon patients with LM between 2010 and 2015 were selected from the Surveillance, Epidemiology, and End Results database (SEER). Fine and Gray's analysis and K-M survival analysis were utilized to explore the impacts of the number of sites of EHMs and different sites of EHMs on prognosis. Finally, a prognostic nomogram model based on the number of sites of EHMs was constructed, and a string of validation methods was conducted, including concordance index (C-index), receiver operating characteristic curves (ROC), and decision curve analysis (DCA). Results: Patients without EHMs had better prognoses in cancer-specific survival (CSS) and overall survival (OS) than patients with EHMs (p < 0.001). Varied EHM sites of patients had different characteristics of primary location site, grade, and histology. Cumulative incidence rates for CSS surpassed that for other causes in patients with 0, 1, 2, ≥ 3 EHMs, and the patients with more numbers of sites of EHMs revealed worse prognosis in CSS (p < 0.001). However, patients with different EHM sites had a minor difference in cumulative incidence rates for CSS (p = 0.106). Finally, a nomogram was constructed to predict the survival probability of patients with EHMs, which is based on the number of sites of EHMs and has been proven an excellent predictive ability. Conclusion: The number of sites of EHMs was a significant prognostic factor of CC patients with LM. However, the sites of EHMs showed limited impact on survival. Furthermore, a nomogram based on the number of sites of EHMs was constructed to predict the OS of patients with EHMs accurately.