The unipolar/bipolar pacing mode of pacemaker is related to its circuit impedance, which affects the battery life. In this study, the in vitro experiment scheme of pacemaker circuit impedance test was constructed. The human blood environment was simulated by NaCl solution, and the experimental environment temperature was controlled by water bath. The results of in vitro experiments showed that under the experimental conditions similar to clinical human parameters, the difference between the circuit impedance of bipolar mode and unipolar mode is 120~200 Ω. The results of the in vitro experiment confirmed that the circuit impedance of bipolar circuit was larger than that of unipolar mode, which was found in clinical practice. The results of this study have reference value to the optimization of pacing mode and the reduction of pacemaker power consumption.
Cardiac Pacing, Artificial/methods* ; Electric Impedance ; Humans ; Pacemaker, Artificial ; Prostheses and Implants

OBJECTIVE: To analyze the results of percutaneous core needle biopsy for bone tumors in upper limbs with pathologic fracture and to find the possible factors that could impact the results. METHODS: The including criteria for this study was the patients who had received percutaneous core needle biopsy and definitive surgery, whose tumor was located at upper limb with pathologic fracture. From January 2015 to December 2019, seventy-seven patients were enrolled. There were 55 males and 22 females. The median age was 27 years old (range:5 to 88 years old). The tumor located at humerus in 67 cases, radius in 8 cases and ulna in 2 cases. If the pathologic diagnosis of core needle biopsy was the same with the definitive surgery, it was defined as "correct". If the pathologic diagnosis of biopsy for benign or malignant was right but the exact diagnostic name was not the same with definitive surgery, it was defined as "supportive". If the pathologic diagnosis of biopsy for benign or malignant was not correct, it was defined as "wrong". We retrospectively analyzed the accuracy and impact factors for core needle biopsy. RESULTS: The result was "correct" in 63 cases(81.8%), "supportive" in 14 cases(18.2%), and "wrong" in 0 cases. We analyzed the gender, age, location, fracture displacement, the destroyed type for bone tumor, soft tissue mass, fluid area in the tumor as the factors. The results showed the rate for "correct" was significantly higher when the tumor had soft tissue mass ( CONCLUSION The accuracy of percutaneous core needle biopsy for upper limb bone tumor with pathologic is high and acceptable. The biopsy chosen the soft tissue mass area can increase the accuracy.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Biopsy, Large-Core Needle ; Bone Neoplasms ; Child ; Child, Preschool ; Female ; Fractures, Spontaneous ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Soft Tissue Neoplasms ; Upper Extremity ; Young Adult

Objective:To observe the effects of Cnidii Fructus hypnotic active components （CHC） on the behaviors of rats with p-chlorophenylalanine （PCPA）-induced insomnia and melatonin （MT） synthesis rate-limiting enzyme arylalkylamine N-acetyltransferase （AANAT）， and explore the protective mechanism of CHC on the pineal gland. Method:Male SD rats of SPF grade were randomly divided into a blank control group， a model group， a MT group， and high-， medium-， and low-dose CHC groups with 10 rats in each group. Except for the blank control group， other groups received 4.5% PCPA suspension at 10 mL·kg^-1， intragastric administration， for two consecutive days. After PCPA model of insomnia was established， normal and model groups were gavaged at the same volume of 2% Tween-80， MT control group （10 mg·kg^-1）， CHC was high， medium and low （60， 30， 15 mg·kg^-1）， 10 mL·kg^-1， once a day， for consecutive 7 days. Four days after administration， open field， elevated cross maze， and pentobarbital sodium-induced sleep tests were conducted， respectively. Serum MT was detected by enzyme-linked immunosorbent assay. The mRNA expression level of AANAT was determined by real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR）. The expression of AANAT protein in the pineal gland was detected by Western blot. Result:Compared with the results in the blank control group， the total distance of open field activity and standing times and duration in the central area were increased （P<0.05， P<0.01）， the proportions of open arm entry （OE%） and open arm time （OT%） were decreased （P<0.05）， and the sleep latency was prolonged （P<0.01） in the model group. Compared with the model group， no significant difference was observed in the low-dose CHC group， while other groups exhibited reduced total distance of activity （P<0.05， P<0.01）， elevated OE% （P<0.05）， shortened sleep latency， and prolonged sleep time （P<0.05， P<0.01）. Compared with the serum MT in the blank control group， that in the model group was decreased （P<0.01）. Compared with the model group， no significant difference was observed in the low-dose CHC group， while other groups displayed increased serum MT （P<0.05）. The mRNA and protein expression of AANAT was decreased in the model group as compared with that in the blank control group （P<0.01）. Compared with the model group， the MT group and the high-dose CHC group showed up-regulated expression （P<0.05）. Conclusion:CHC improved the behavioral indexes of PCPA-induced insomnia， increased the synthesis and secretion of MT in pineal cells， and elevated the serum MT level， which was related to the up-regulation of the mRNA and protein expression of AANAT in the pineal gland.

Objective To explore the clinical characteristics of autoimmune disease with dual seropositive antibodies of leucine-rich glioma inactivated 1(LGI1)and contactin-associated protein 2(Caspr2).Methods The clinical data of seven patients with dual seropositive LGI1 and Caspr2 antibodies who were admitted to the Neurology Department of Peking Union Medical College Hospital from July 2014 to December 2017 were retrospectively analyzed.Results Central,peripheral and autonomic nervous systems were all involved in the seven cases;100%(7/7)presented with insomnia,myokymia,neuropahic pain and hyperhydrosis;71%(5/7)showed memory decline or psychiatric and behavioral symptoms;57%(4/7)had urinary hesitation or constipation;and 43%(3/7)had seizure.Electromyography showed 100%(6/6) of the patients had prolonged afterdischarges following normal M waves and/or abnormal spontaneous firing.Electroencephalography revealed slow waves or basic rhythm slowing in 71%(5/7)of patients.Electrocardiography showed sinus tachycardia,axis deviation,and prolonged QT intervals in 71%(5/7)of patients.One patient died from arrhythmia before immunotherapy.One died from pulmonary infection after immunotherapy.Improvement with immunotherapy was documented in the other five cases.No relapse was noted during the 1-2-year follow-up.Conclusions Autoimmune disease with dual seropositive antibodies of LGI1 and Caspr2 can diffusely affect the central,peripheral,and autonomic nervous systems.The possibility of this disease should be considered in patients with acute and subacute onset of neuropsychiatric symptoms,especially in patients with accompanying insomnia,myokymia,and hyperhydrosis.
Autoantibodies ; blood ; Autoimmune Diseases ; immunology ; Humans ; Membrane Proteins ; immunology ; Nerve Tissue Proteins ; immunology ; Proteins ; immunology ; Retrospective Studies

Objective Circular RNA is a research hotspot of non-coding RNAs. The purpose of this study was to investigate the basic characteristics and expression effect of the overexpression vectors of circular RNA hsa_circ_0082626 transcribed from antiviral gene ZC3HAV1. Methods The basic characteristics of hsa_circ_0082626 were studied by the verification of reverse cleavage site, RNase digestion assay and intracellular distribution location with extraction of cytoplasmic and nuclear RNA. In the RNase digestion assay, samples were divided into RNase R treatment group and control group. RNase. 20 U (2 U/μg) of RNase R was added to the R treatment group, and the control group was replaced with an equivalent amount of ddH2O to detect changes in expression levels after RNase treatment. The cells were divided into 2 groups: overexpression group and negative control group. At 24, 48 and 72 h after transfection, cells were collected to detect the expression of circular RNA by RT-qPCR. Results Compared with the control group, the expression of ZC3HAV1, CDR1as and GAPDH in the RNase R treatment group was increased (0.144±0.002 vs 1.000±0.016, 0.772±0.058 vs 1.000±0.122, 0.077±0.009 vs 1.000±0.164, P<0.05). Hsa_circ_0082626 could resist the treatment of RNase R and was mainly distributed in cytoplasm. The expression level of hsa_circ_0082626 in the overexpression group was significantly higher than that in the negative control group, and the expression level was the highest at 48 h after transfection. Conclusion The characteristics of hsa_circ_0082626 reverse cleavage site, RNase resistance and expression in cells were successfully analyzed, which proved that hsa_circ_0082626 does have a circular structure. The overexpression vector of hsa_circ_0082626 was successfully constructed to provide an experimental basis for the biological function and mechanism of RNA hsa_circ_0082626.

Objective To analyze the status of quality indicators(QI) on specimen acceptability and establish preliminary qual ity specification.Methods Web based External Quality Assessment system was used to collect data of laboratories partici pated in "Medical quality control indicators in clinical laboratory" from 2015 to 2017,including once in 2015 and 2017 and twice in 2016.Rate and sigma scales were used to evaluate incorrect sample type,incorrect sample container,incorrect fill level and anticoagulant sample clotted.The 25th percentile (P25) and 75th percentile (P75) of the distribution of each QI were employed to establish the high,medium and low specification.Results 5 346,7 593,5 950 and 6 874 laboratories sub mitted the survey results respectively.The P50 of biochemistry (except incorrect fill level),immunology and microbiology reach to 6σ.The P50 of clinical laboratory is 4 to 6σ except for incorrect sample container.There is no significant change of the continuous survey results.Based on results in 2017 to establish the quality specification,the P25 and P75 of the four QIs is 0 and 0.084 4 ％,0 and 0.047 6 ％,0 and 0.114 2 ％,0 and 0.078 4 ％,respectively.Conclusion According to the results of the survey,most laboratories had a faire performance in biochemistry,immunology and microbiology,and clinical laboratory needs to be strengthened.Laboratories should strengthen the laboratory information system construction to ensure the actual and reliable data collection,and make a long time monitoring to achieve a better quality.

BACKGROUNDWide resection margins of osseous tumors are associated with a low incidence of local recurrence, making accurate measurement of the intraosseous extent of primary malignant long bone tumors is crucial. We compared the intraosseous tumor extent assessed by magnetic resonance imaging (MRI) with the gross specimen to evaluate the accuracy of MRI.

METHODSA total of 255 patients with primary malignant tumors in the long bones were included. Using MRI, we defined the length of tumor as the distance from the articular surface to the boundary between abnormal and normal marrow signal. The extent of the abnormal intraosseous signal was measured on unenhanced T1-weighted (T1WI) magnetic resonance images after chemotherapy. All gross surgical specimens were sectioned, and tumor extent was measured. Wilcoxon signed-rank test was used to test the differences between MRI and gross specimen findings. Spearman's correlation analysis was used to test the correlation between groups.

RESULTSMedian tumor length by gross specimen (112 mm; range, 45-300 mm) was longer than that by MRI (108 mm; range, 45-304 mm; Z = -6.916, P < 0.001). Of 255 images, tumor length was accurately represented on 27 T1WI magnetic resonance images, overestimated on 79 images, and underestimated on 149 images. The median difference between imaging and gross specimen measurements was 2.0 mm (range: 1.0-15.0 mm) for the 79 cases where tumor length was overestimated, and 5.0 mm (range: 1.0-18.0 mm) for the 149 cases where tumor length was underestimated. The Spearman correlation demonstrated a high correlation of tumor length on gross specimen with the tumor length on MRI (R = 0.99, P < 0.01).

CONCLUSIONSWe conclude that preoperative MRI could be a useful method in determining intramedullary malignant bone tumor boundaries and may serve as an accepted assessment method of long bone tumors before limb-sparing surgery.

Background: Wide resection margins of osseous tumors are associated with a low incidence of local recurrence, making accurate measurement of the intraosseous extent of primary malignant long bone tumors is crucial. We compared the intraosseous tumor extent assessed by magnetic resonance imaging (MRI) with the gross specimen to evaluate the accuracy of MRI. Methods: A total of 255 patients with primary malignant tumors in the long bones were included. Using MRI, we defined the length of tumor as the distance from the articular surface to the boundary between abnormal and normal marrow signal. The extent of the abnormal intraosseous signal was measured on unenhanced T1?weighted (T1WI) magnetic resonance images after chemotherapy. All gross surgical specimens were sectioned, and tumor extent was measured. Wilcoxon signed?rank test was used to test the differences between MRI and gross specimen findings. Spearman's correlation analysis was used to test the correlation between groups. Results: Median tumor length by gross specimen (112 mm; range, 45–300 mm) was longer than that by MRI (108 mm; range, 45–304 mm;Z = ?6.916, P < 0.001). Of 255 images, tumor length was accurately represented on 27 T1WI magnetic resonance images, overestimated on 79 images, and underestimated on 149 images. The median difference between imaging and gross specimen measurements was 2.0 mm (range: 1.0–15.0 mm) for the 79 cases where tumor length was overestimated, and 5.0 mm (range: 1.0–18.0 mm) for the 149 cases where tumor length was underestimated. The Spearman correlation demonstrated a high correlation of tumor length on gross specimen with the tumor length on MRI (R = 0.99, P < 0.01). Conclusions: We conclude that preoperative MRI could be a useful method in determining intramedullary malignant bone tumor boundaries and may serve as an accepted assessment method of long bone tumors before limb?sparing surgery.