Intelligent Wearable Wrist Pulse Detection System Based on Piezoelectric Sensor Array.

The human radial artery pulse carries a rich array of biomedical information. Accurate detection of pulse signal waveform and the identification of the corresponding pulse condition are helpful in understanding the health status of the human body. In the process of pulse detection, there are some problems, such as inaccurate location of radial artery key points, poor signal noise reduction effect and low accuracy of pulse recognition. In this system, the pulse signal waveform is collected by the main control circuit and the new piezoelectric sensor array combined with the wearable wristband, creating the hardware circuit. The key points of radial artery are located by an adaptive pulse finding algorithm. The pulse signal is denoised by wavelet transform, iterative sliding window and prediction reconstruction algorithm. The slippery pulse and the normal pulse are recognized by feature extraction and classification algorithm, so as to analyze the health status of the human body. The system has accurate pulse positioning, good noise reduction effect, and the accuracy of intelligent analysis is up to 98.4%, which can meet the needs of family health care.

Developing Single-Atomic Manganese Nanozymes for Synergistic Mild Photothermal/Multienzymatic Therapy.

Synergistic mild photothermal/nanozyme therapy with outstanding hyperthermia performance and excellent multienzyme properties is highly needed for osteosarcoma treatment. Herein, we have developed efficient single-atom nanozymes (SANs) consisting of Mn sites atomically dispersed on nitrogen-doped carbon nanosheets (denoted as Mn-SANs) for synergistic mild photothermal/multienzymatic therapy against osteosarcoma. Benefiting from their black N-doped carbon nanosheet matrices, Mn-SANs showed an excellent NIR-II-triggered photothermal effect. On the other hand, Mn-SANs with atomically dispersed Mn sites have outstanding multienzyme activities. Mn-SANs can catalyze endogenous H2O2 in osteosarcoma into O2 by catalase (CAT)-like activity, which can effectively ease osteosarcoma hypoxia and trigger the oxidase (OXD)-like catalysis that converts O2 to the cytotoxic superoxide anion radical (•O2-). At the same time, Mn-SANs can also mimic glutathione oxidase (GSHOx) to effectively consume the antioxidant glutathione (GSH) in osteosarcoma and inhibit intracellular glutathione peroxidase 4 (GPX4) expression. Such intratumoral •O2- production, GSH depletion, and GPX4 inactivation mediated by Mn-SANs can create a large accumulation of lipid peroxides (LPO) and •O2-, leading to oxidative stress and disrupting the redox homeostasis in osteosarcoma cells, which can ultimately induce osteosarcoma cell death. More importantly, heat shock proteins (HSPs) can be significantly destroyed via Mn-SAN-mediated plentiful LPO and •O2- generation, thus effectively impairing osteosarcoma cells resistant to mild photothermal therapy. Overall, through the cooperative effect of chemical processes (boosting •O2-, consuming GSH, and enhancing LPO) and biological processes (inactivating GPX4 and hindering HSPs), collaborative mild photothermal/multienzymatic therapy mediated by Mn-SANs is a promising strategy for efficient osteosarcoma treatment.

The PI3K/AKT cell signaling pathway is involved in regulation of osteoporosis.

BACKGROUND: Osteoporosis is a systemic skeletal disease with the high incidence, serious complications, financial burden, and heavily decrease in living quality. METHODS: Proliferation of osteoblast was tested by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) method, alkaline phosphatase (ALP) activity of osteoblasts was tested by ALP REAGENT, Calcium level was determined by a colorimetric assay, mRNA expression of phosphoinositide-3 kinase (PI3K), 3-phosphoinositide-dependent protein kinase 1 (PDK1), Akt, Caspase-3, Caspase-7, Caspase-9, osteocalcin (OCN), Osterix and Runx2 of osteoblasts was tested by RNA preparation and quantitative reverse transcription polymerase chain reaction (RT-PCR), and protein expression of phospho-PI3K, phospho-PDK1 and phospho-Akt was measured by Western Blot analysis. RESULTS: In osteoporosis model rats, it found that mRNA expression of PI3K, PDK1 and Akt showed no changes while protein expression of phospho-PI3K, phospho-PDK1 and phospho-Akt in bone tissue was decreased dramatically. To further characterize the molecular mechanisms that regulate osteoporosis, we examined the contribution of the PI3K/Akt cell signaling pathway in cultured osteoblasts. It suggested that, the blockade of PI3K activation by LY294002, a specific inhibitor of the PI3K/Akt signaling pathway in osteoblasts, heavily inhibited cell proliferation, ALP activity, calcium accumulation, and mRNA expression of OCN, Osterix and Runx2. However, mRNA expression of Caspase-3 and Caspase-9 was promoted accordingly. CONCLUSION: The in vivo and in vitro studies indicated that the PI3K/Akt cell signaling pathway is involved in the inhibition of osteoporosis through promoting osteoblast proliferation, differentiation and bone formation.

Value of PAX1 Methylation Analysis by MS-HRM in the Triage of Atypical Squamous Cells of Undetermined Significance.

BACKGROUND: Detection of cervical high grade lesions in patients with atypical squamous cells of undetermined significance (ASCUS) is still a challenge. Our study tested the efficacy of the paired boxed gene 1 (PAX1) methylation analysis by methylation-sensitive high-resolution melting (MS-HRM) in the detection of high grade lesions in ASCUS and compared performance with the hybrid capture 2 (HC2) human papillomavirus (HPV) test. MATERIALS AND METHODS: A total of 463 consecutive ASCUS women from primary screening were selected. Their cervical scrapings were collected and assessed by PAX1 methylation analysis (MS-HRM) and high-risk HPV-DNA test (HC2). All patients with ASCUS were admitted to colposcopy and cervical biopsies. The Chi- square test was used to test the differences of PAX1 methylation or HPV infection between groups. RESULTS: The specificity, sensitivity, and accuracy for detecting CIN2 + lesions were: 95.6%, 82.4%, and 94.6%, respectively, for the PAX1 MS-HRM test; and 59.7%, 64.7%, and 60.0% for the HC2 HPV test. CONCLUSIONS: The PAX1 methylation analysis by MS-HRM demonstrated a better performance than the high-risk HPV-DNA test for the detection of high grade lesions (CIN2 +) in ASCUS cases. This approach could screen out the majority of low grade cases of ASCUS, and thus reduce the referral rate to colposcopy.

Non-Markovian full counting statistics in quantum dot molecules.

Full counting statistics of electron transport is a powerful diagnostic tool for probing the nature of quantum transport beyond what is obtainable from the average current or conductance measurement alone. In particular, the non-Markovian dynamics of quantum dot molecule plays an important role in the nonequilibrium electron tunneling processes. It is thus necessary to understand the non-Markovian full counting statistics in a quantum dot molecule. Here we study the non-Markovian full counting statistics in two typical quantum dot molecules, namely, serially coupled and side-coupled double quantum dots with high quantum coherence in a certain parameter regime. We demonstrate that the non-Markovian effect manifests itself through the quantum coherence of the quantum dot molecule system, and has a significant impact on the full counting statistics in the high quantum-coherent quantum dot molecule system, which depends on the coupling of the quantum dot molecule system with the source and drain electrodes. The results indicated that the influence of the non-Markovian effect on the full counting statistics of electron transport, which should be considered in a high quantum-coherent quantum dot molecule system, can provide a better understanding of electron transport through quantum dot molecules.

Negative differential conductance and super-Poissonian shot noise in single-molecule magnet junctions.

Molecular spintroinic device based on a single-molecule magnet is one of the ultimate goals of semiconductor nanofabrication technologies. It is thus necessary to understand the electron transport properties of a single-molecule magnet junction. Here we study the negative differential conductance and super-Poissonian shot noise properties of electron transport through a single-molecule magnet weakly coupled to two electrodes with either one or both of them being ferromagnetic. We predict that the negative differential conductance and super-Poissonian shot noise, which can be tuned by a gate voltage, depend sensitively on the spin polarization of the source and drain electrodes. In particular, the shot noise in the negative differential conductance region can be enhanced or decreased originating from the different formation mechanisms of negative differential conductance. The effective competition between fast and slow transport channels is responsible for the observed negative differential conductance and super-Poissonian shot noise. In addition, we further discuss the skewness and kurtosis properties of transport current in the super-Poissonian shot noise regions. Our findings suggest a tunable negative differential conductance molecular device, and the predicted properties of high-order current cumulants are very interesting for a better understanding of electron transport through single-molecule magnet junctions.

A rabbit model of graded primary mechanical injury to brainstem.

OBJECTIVE: To introduce a new animal model of graded mechanical primary brainstem injury (BSI). METHODS: Altogether 45 rabbits were subjected to BSI by type II biological impact machine designed by the Third Military Medical University. The animals were divided into 4 experimental groups (n equal to 10) and 1 control group (n equal to 5) according to different magnitudes of impact pressure imposed on the occipital nodule: Group 1, 500-520 kPa; Group 2, 520-540 kPa; Group 3, 540-560 kPa; Group 4, 560-580 kPa and Group 5, 0 kPa with 20 kPa increase in each grade. The impact depth was a constant 0.5 cm. After injury, the clinical symptoms and signs as well as pathological changes were observed. RESULTS: Rabbits in Group 1 revealed mild physiological reaction of BSI. They had localized cerebral contusion with punctate hemorrhage and subarachnoid hemorrhage (SAH) was limited to the peripheral tissues at the impact area. In Group 2, obvious physiological reaction was observed. Local pathological lesions reached the superficial layer of brainstem tissues; focal hemorrhage and girdle-shaped SAH in basilar pon were observed under microscope. In Group 3, BSI was more severe with a long respiratory depression. Pathological lesions reached the inner portion of brainstem with massive hemorrhage and the whole brainstem was wrapped by subarachnoid hematoma. In Group 4, most rabbits died due to severe BSI. Pathological lesions deepened to the central brainstem with wide pathological change, rapture of the medulla oblongata central canal. Group 5 was the control group, with normal brainstem structure and no lesion observed. CONCLUSION: This model successfully simulates different levels of brainstem mechanical injury and clearly shows the subsequent pathological changes following injury. It takes two external parameters (impact pressure and depth) and has a similar injury mechanism to clinical accelerating BSI. Moreover it is reproducible and stable, thus being be- neficial for exploring pathophysiological mechanism, diagnosis and forensic identification of various degrees of BSI.

[Outcomes of anterior versus posterior instrumentation under different surgical procedures in the treatment of thoracolumbar spinal tuberculosis in adults].

OBJECTIVE: To compare the outcomes of anterior verus posterior instrumentation under different surgical procedures in the surgical management of thoracolumbar spinal tuberculosis (TB). METHODS: Between January 2004 and December 2009, 241 adult patients with thoracolumbar spinal TB underwent radical debridement and strut grafting plus anterior or posterior instrumentation in single-stage or two-stages. The mean age was 39 years (range: 16 - 67). The mean follow-up period for 189 patients was 37 months (range: 22 - 72). Among them, 157 cases underwent > 3 weeks of chemotherapeutic regimen of isoniazid, rifampin, pyrazinamide and ethambutol and the remaining 32 were operated for neurological impairment after 6-18 h with the same chemotherapeutic regimen. Except for 8 patients with skip lesions undergoing hybrid anteroposterior instrumentation, anterior instrumentation was utilized in 74 patients (Group A) and posterior instrumentation in 107 patients (Group B). RESULTS: In both groups, local symptoms of all patients were relieved significantly 1-3 weeks postoperatively. And 10/14 cases (71%) in Group A and 14/19 cases (74%) in Group B with neurological deficits had excellent or good clinical outcomes (P > 0.05). The levels of erythrocyte sedimentation rates (ESR) returned from 43.6 mm/h and 42.4 mm/h preoperatively to normal at 8-12 weeks postoperatively. Kyphosis degrees were corrected by a mean of 11.5° in Group A and 12.6° in Group B (P < 0.01). The correction loss was 6.8° in Group A and 6.1° in Group B at the last follow-up (P < 0.01). Fusion rates of the grafting bone were 92.5% and 91.8% respectively at the final follow-up (P > 0.05). Severe complications did not occur. CONCLUSION: Either anterior or posterior instrumentation can obtain good results in correction and maintenance of deformity, clearance of foci, decompression of spinal cord and pain relief in the treatment of thoracolumbar spinal TB as long as the surgical indications are properly selected. Posterior instrumentation may be superior to anterior instrumentation in the correction and maintenance of deformity.

[Surgical treatment of lower lumbar tuberculosis with different operative procedures].

OBJECTIVE: To evaluate the surgical indications and clinical effectiveness of different operative procedures in the treatment of lower lumbar tuberculosis. METHODS: From June 2001 to Oct 2008, 72 patients with lower lumbar tuberculosis were treated by different operative procedures. Including 38 males and 34 females, with an average age of 38.5 years old ranging from 16 to 70 years. The average duration of symptom was 6.8 months (ranging from 4 months to 2 years). A single vertebrae was involved in 10 patients,two contiguous vertebrae in 50 cases and three vertebrae in 12 cases. The average preoperative lordotic angle was 13.1 degree (ranging from -5.0 degrees to 34.0 degrees). Three different operative procedures included: (1) posterior debridement and posterolateral fusion and posterior instrumentation in 28 patients; (2) anterior radical debridement and anterior fusion and anterior instrumentation in 32 patients; (3) image-guided percutaneous drainage (PCD) of tuberculous abscesses in 12 patients. The selection of the procedure was made according to the degree of the lesions. The resolution of inflammatory process, bony fusion, correction of sagittal angles and JOA scores were used for evaluating the result of the surgery and the complications were analyzed. RESULTS: All patients were followed up from 1.5 to 8.0 years (means 3.6 years). PCD was an effective treatment in 11 out of the 12 patients, one required surgical debridement and fusion. Among them, 57 (95%, 57/60) patients were treated by open operation showed successful bony fusion. The complications maily included common iliac vein injury in 3 patients, dural tear in 2 patients, they were all cured by intro-or postoperative treatment. The average immediate post-operative lordotic angle was 27.3 degree (35.0 degrees to 16.0 degrees), the average lordotic angle was 25.6 degree (33.0 degrees to 15.0 degrees) at final follow-up. Preoperatively and at final follow-up, JOA scores were respectively (15.2 +/- 3.4), (25.6 +/- 2.4) (P<0.01). CONCLUSION: Different operative procedures should be selected to treat lower lumbar tuberculosis according to the degree of lesions. Aggressive surgical treatment was found helpful in the resolution of inflammatory process and correcting the loss of lordosis, preventing progression of kyphosis.

[Surgical treatment for the thoracolumbar spinal tuberculosis with paraplegia].

OBJECTIVES: To explore the long-term effects,operating opportunity,indication of anterior debridement and decompression and bone graft in treating thoracolumbar tuberculosis with paraplegia. METHODS: From March 2006 to September 2008, the data of 56 patients with spinal tuberculosis were retrospectively analyzed. They were 36 cases male and 20 cases female, the age in ranging from 19 to 78 years with the mean of 42.5 years; course of disease in ranging from 3 months to 4 years. The lesion level was in T11-L2, including one stage in 6 cases, two stages in 42 cases, three stages in 7 cases, four stages in 1 case. According to the Frankel grade, grade A in 5 cases, B in 25, C in 21, D in 5. Preoperative Cobb angle had 30 cases under 30 degrees, 24 cases in 30 degrees-60 degrees, 2 cases more than 60 degrees [averaged in (35.0 +/- 3.3) degrees]. The mean VAS was 7.3 +/- 2.1 preoperatively. All patients had chemotherapy for 2-3 weeks. The clinical effects were evaluated by Cobb angle, VAS, condition of Frankel grade and fusion segments. RESULTS: All patients were followed up from 12 to 38 months with an average of 24 months. All wound obtained primary healing. The Cobb angle was(19.0 +/- 5.5) degrees immediately after operation, and lost (1.8 +/- 0.7) degrees at the follow up. The mean VAS was 1.4 +/- 0.3 postoperatively and 1.3 +/- 0.4 at final follow up. The Cobb angle and VAS significant improved in postoperatively (P < 0.05), and there was no statically difference between after operation and last follow up(P > 0.05). At 1 year after operation, all patients obstained successful bony fusion. Among 51 cases incomplete paraplegia recovered partially or completely (over Frankel D) through chemotherapy and rehabilitation training for 1-1.5 years; 5 cases of complete paraplegia had partially recovered, 3 cases from Frankel A to C, 2 cases from Frankel A to B. CONCLUSION: Base on the chemotherapeutic effect, paraplegia reason and location, total body condition to select different operative opportunity can effectively relieve spinal compression, stabilize spinal column, correct kyphosis and promote recovery of paraplegia.

[Surgical treatment of drug-resistant spinal tuberculosis].

OBJECTIVE: To study the curative effect of surgical treatment of drug-resistant spinal tuberculosis. METHODS: From March 2005 and April 2009, the clinical data of 60 patients with drug-resistant spinal tuberculosis were retrospectively analyzed. Including 36 males and 24 females; aged from 5 to 79 years with an average of 47.3 years. Thirty-four patients had neurological deficits, among them, 2 cases were grade A, 5 cases were grade B, 13 cases were grade C, 14 cases were grade D according to ASIA standard. According to the severity and location of the infection, the patients underwent anterior, posterolateral costotransversectomy or posterior debridement and bone grafting and internal fixation. The antituberculous chemotherapy for a total of 12 to 18 months was guided by conventional and genotypic drug susceptibility testing. Tubercular relapse, neurological function, spinal fusion were observed by ASIA grade, X-ray and CT scan. RESULTS: All cases were followed up from 1 to 5 years with an average of 3.1 years. Recurrence was found in 2 cases who were cured after second operation. 34 cases with neurological deficits recovered totally or partially. X-ray or CT films showed spinal fusion in 57 patients. CONCLUSION: The therapeutic effect of individuall operative options is good in treating drug-resistant spinal tuberculosis after antituberculous chemotherapy based on conventional and genotypic drug susceptibility testing.

[Variety of ESR and C-reactive protein levels during perioperative period in spinal tuberculosis].

OBJECTIVE: To investigate the clinical significance of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in the treatment of spinal tuberculosis. METHODS: Sixty-seven patients (41 males and 26 females, ranging in age from 23 to 61 years) with active spinal tuberculosis in our hospital (from Mar. 2004 to Mar. 2007) were included in this study. The tuberculosis focus were located either in cervical spine, thoracic spine or in lumbar spine. After 4 to 6 weeks anti-tuberculosis chemotherapy, all the patients underwent one-stage operation (focus debridment) and auto-bone graft combined with internal fixation. Blood test for ESR and CRP were carried out at different times before and after operation. RESULTS: The average ESR was (79.4 +/- 35.6) mm/h, and the average CRP was (44.3 +/- 17.5) mg/L before chemotherapy, indicating active tuberculosis focus. After 4 to 6 weeks chemotherapy, the average ESR was (45.3 +/- 21.0) mm/h,and the average CRP was (26.7 +/- 11.8) mg/L, the differences were statistically (P < 0.05), and the clinical symptoms of spinal tuberculosis relieved in all patients. Four weeks after operation, the average ESR dropped to (42.8 +/- 16.5)mm/h, the average CRP dropped to (23.8 +/- 10.0) mg/L statistically (P < 0.05). Eight weeks after operation, the average value of ESR and CRP were at normal level in 47 cases, indicating inactive tuberculosis focus. Focus healing was achieved in 65 patients after short-term chemotherapy. CONCLUSION: The level of ESR and CRP are high in active spinal tuberculosis and low when focus controlled. ESR and CRP are reliable parameters in evaluation the treatment and prognosis of spinal tuberculosis.

[The mid- or long-term clinical results of prosthetic disc nucleus replacement in the treatment of lumbar disc disease].

OBJECTIVE: To evaluate the mid- or long-term clinical results and the factors that influence the outcomes of prosthetic disc nucleus (PDN) replacement in the treatment of lumbar disc disease. METHODS: Thirty-four patients who underwent the PDN replacement from March 2002 to October 2003 were followed for an average of 52.6 months (range from 48 to 66 months). Twenty patients were discogenic low back pain, 14 patients were lumbar disc herniation. The follow-up results were evaluated by using the Oswestry disability index (ODI) and the visual analogue scales (VAS) through direct examinations and questionnaires. ODI was 58.4% preoperatively, and VAS was 7.4. Radiography was also used to measure the range of motion (ROM) and disc height of the operative segment, and findings were compared with those on preoperative radiographs. RESULTS: Twelve months after operation, a significant proportion of patients recovered from low back pain or leg pain, ODI decreased to averaged 18.2%. VAS decreased to 1.8, the average increase of the postoperative disc height was 17.6%, ROM was 9.2 degrees. At the final followup, all patients with deteriorated leg radicular symptoms improved, ODI increased from 18.2% 12 months after operation to averaged 31.2%. Low back pain became more serious in 18 patients. VAS increased from 1.8 to 3.1, the average decrease of the postoperative to preoperative disc height was 13.5%, ROM decreased to 6.8 degrees. The rate of degeneration or breakages of the end plates was 64.7% (22/34), implant device migrations were observed in 25 patients. CONCLUSIONS: The mid- or long-term outcome of PDN replacement in the treatment of degenerative lumbar disc disease is not as encouraging as that of the short-term follow-up. It is neither effective in term of restoration of the intervertebral disc height nor increase of the ROM of the operative segment, complication rates are significantly higher, and inferior results are to be expected. The selection of suitable surgical candidates and determination of valid indications for operative treatment are very important.

[Surgical treatment of spinal tuberculosis in aged].

OBJECTIVE: To investigate perioperative features and results of surgical treatment of spinal tuberculosis in aged. METHODS: Review the clinical data of 36 aged with spinal tuberculosis from May 1998 to June 2005 retrospectively. The average age was 70.2 years. The sites of infection included 3 cervical, 9 thoracic, 13 thoracolumbar and 11 lumbar. 28 patients suffered 1 or more complications at least and among of them, there were 18 patients have cerebral or heart vascular disease, 16 patients have diabetes mellitus. Before operation, all patients consulted with internal stuff for the proper treatment of concomitant disease. The surgical procedures include: CT guided percutaneous catheter drainage in 3 patients, anterior debridement and bony grafting with anterior instrumentation fixation in 12 patients, anterior debridement and bony grafting with posterior fixation in 5 patients, posterolateral costotransversectomy debridement and interbody fusion with posterior fixation in 7 patients, posterior debridement and posterior fixation in 9 patients. The mean followed-up period was 3 years and 10 months (from 1.5 to 6 years). RESULTS: One died at two week after the operation. Tuberculous infection was controlled in other patients and no recurrence. Two patients died because of myocardial infarction and cerebral hemorrhage respectively at 1.5 and 2.5 years after operation. Bone fusion was achieved in 31 patients. The deformity was partial corrected at the final follow-up. Among 20 cases with neurologic deficit, 11 cases were completely recovered, 5 cases were partly improved. CONCLUSIONS: If the associated disorders and postoperative complications are properly handled, aged patients can endure surgical treatment for spinal tuberculosis. Instrumentation fixation provides adequate stability and promote recovery.