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Background. Type 2 diabetes (T2D) as a worldwide chronic disease combined with the COVID-19 pandemic prompts the need for improving the management of hospitalized COVID-19 patients with preexisting T2D to reduce complications and the risk of death. This study aimed to identify clinical factors associated with COVID-19 outcomes specifically targeted at T2D patients and build an individualized risk prediction nomogram for risk stratification and early clinical intervention to reduce mortality. Methods. In this retrospective study, the clinical characteristics of 382 confirmed COVID-19 patients, consisting of 108 with and 274 without preexisting T2D, from January 8 to March 7, 2020, in Tianyou Hospital in Wuhan, China, were collected and analyzed. Univariate and multivariate Cox regression models were performed to identify specific clinical factors associated with mortality of COVID-19 patients with T2D. An individualized risk prediction nomogram was developed and evaluated by discrimination and calibration. Results. Nearly 15% (16/108) of hospitalized COVID-19 patients with T2D died. Twelve risk factors predictive of mortality were identified. Older age (HR = 1.076, 95% CI = 1.014–1.143,p=0.016), elevated glucose level (HR = 1.153, 95% CI = 1.038–1.28,p=0.0079), increased serum amyloid A (SAA) (HR = 1.007, 95% CI = 1.001–1.014,p=0.022), diabetes treatment with only oral diabetes medication (HR = 0.152, 95%CI = 0.032–0.73,p=0.0036), and oral medication plus insulin (HR = 0.095, 95%CI = 0.019–0.462,p=0.019) were independent prognostic factors. A nomogram based on these prognostic factors was built for early prediction of 7-day, 14-day, and 21-day survival of diabetes patients. High concordance index (C-index) was achieved, and the calibration curves showed the model had good prediction ability within three weeks of COVID-19 onset. Conclusions. By incorporating specific prognostic factors, this study provided a user-friendly graphical risk prediction tool for clinicians to quickly identify high-risk T2D patients hospitalized for COVID-19.

Programmed cell death ligand 1 (PD-L1) is a key suppressor of the cytotoxic immune response. In colorectal carcinoma (CRC), PD-L1 expression results in immune escape and poor prognosis. Extensive researches suggested that metformin had a potential efficacy of enhancing anti-tumor immune response in different types of cancer. However, the detail mechanisms underlying the efficacy in CRC are unclear. Here, we showed that metformin decreases PD-L1 and YAP1 expression in vitro and in vivo. After silencing or inhibiting YAP1 expression by Verteporfin (VP), the inhibitor of YAP1, the expression of PD-L1 were decreased in protein level in CRC cells. Furthermore, metformin directly phosphorylated YAP1 and restricted YAP1 to entry in the nucleus, so that PD-L1 was reduced via western blot and immunofluorescence assays in SW480 and HCT116 cells. Finally, subcutaneous xenotransplanted tumor models of HCT116 cells were established in BALB/c nude mice. Compared with the control group, PD-L1 and YAP1 expressions in tumor tissues, detected by immunohistochemistry, were reduced in the group of metformin treatment. These findings illuminate a new regulatory mechanism, metformin activates Hippo signaling pathway to regulate PD-L1 expression and suggests that metformin has the possibility to increase the efficacy of immunotherapy in human CRC.

Based on microwave transmission theory and the ferromagnetic resonance mechanism, a lumped equivalent circuit model for a symmetrical T-shaped microstrip magnetoelectric (ME) tunable microwave filter was established by combining a straight microstrip ME device and a coupling microstrip ME device. Assuming the electrical tunable equivalent factor of the piezoelectric layer, equivalent circuit parameters were derived where the filter was equivalent to a straight microstrip resonator. Using the magnetostatic surface wave transmission mechanism, a new unit radiation impedance formula was introduced where the filter was equivalent to a coupling microstrip bandpass filter. The corresponding equivalent circuit parameters were calculated and a lumped equivalent circuit of the ME tunable coupling microstrip bandpass filter was established. The insertion loss of the symmetrical T-shaped ME tunable microwave filter was predicted using the lumped equivalent circuit under varied magnetic and electric fields. The comparisons with the simulated results and the experimental results of the electromagnetic field indicated that those were in good agreement, both qualitatively and quantitatively, verifying the validity of the lumped equivalent circuit. The influence of the ME laminate’s size and the external bias magnetic field on the filter’s performance was predicted by the lumped equivalent circuit, which supports the design of ME tunable microwave devices.

Radiation therapy is important for the comprehensive treatment of intracranial tumors. However, the molecular mechanisms underlying the pathogenesis of delayed cognitive dysfunction are not well-defined and effective treatments or prevention measures remain insufficient. In the present study, 60 adult male Wistar rats were randomly divided into three groups, which included a control, whole brain radiotherapy (WBRT) (single dose of 30 Gy of WBRT) and nimodipine (single dose of 30 Gy of WBRT followed by nimodipine injection intraperitoneally) groups. The rats were sacrificed 7 days or 3 months following irradiation. At 3 months, the Morris water maze test was used to assess spatial learning and memory function in rats. The results demonstrated that the WBRT group demonstrated a significantly impaired cognitive performance, decreased numbers of hippocampal Cornu Ammonis (CA)1 neurons and upregulated expression of caspase-3 in the dentate gyrus compared with those in the control and nimodipine groups. Reverse transcription-quantitative polymerase chain reaction analysis demonstrated that the WBRT group exhibited increased ratio of B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 compared with that in control and nimodipine groups on day 7 following irradiation. However, the WBRT group exhibited decreased levels of brain-derived neurotrophic factor (BDNF) compared with that in control and nimodipine groups at 3 months following brain irradiation. The levels of growth-associated protein 43 and amyloid precursor protein between the nimodipine group and WBRT group were not statistically significant. The present study demonstrated that neuron apoptosis may lead to delayed cognitive deficits in the hippocampus, in response to radiotherapy. The cognitive impairment may be alleviated in response to a calcium antagonist nimodipine. The molecular mechanisms involved in nimodipine-mediated protection against cognitive decline may involve the regulation of Bax/Bcl-2 and BDNF in the hippocampus.

This paper introduces the basic concepts and characteristics of virtual reality technology briefly and analyzes the defects of the artificial guiding teaching of the current live working from the angle of skills and safety, combing the power grid’s physical characteristics and virtual reality techniques. By summing up the transmission live working running operating procedures, the methods and means of using virtual reality technology in the teaching and training of the transmission network for live working are proposed. Summary transmission live working training status and analyze the application prospect of the virtual reality technology in the power transmission network live working on the basis of summarizing the power transmission network live working training status. The transmission live working simulation training method brings a new look to the power companies and also does great benefit for the enhancement of the operators' skill level and the improvement of their security awareness of operating.

The training of distribution operators is an important link to ensure the safe operation to effectively enhance the training effect,the paper put forward a new teaching form that combining the line operation and simulation training. It firstly analyzes the distribution network simulation training function demand, then designs training simulation system structure,extracts simulation training process,introduces the key technology:three-dimensional simulation technology,then simulation training process,finally gives the system development example. The application result shows the power line operation simulation training system can effectively guarantee the operation training effect,has a great practical significance.

According to the demand of practical operation of drills in the live working simulation training , sensor technology using in simulation training systems is put forward in this paper.On the bases of brief introduction of sensor technology and summarizing of sensing technology’s application in the simulation training, the sensing system of the live working simulation training system is established.With the sensor system, trainees can simulate a live working process of self participations, achieve real-time interaction with the virtual scene of live working, the objectives of practical operation of drills is achieved, the effect of the simulation training is effectively improved.

The paper introduces the basic concept and characteristics of virtual reality technology, then, on the basis of summarizing the power distribution network live working training status, analysis of the virtual reality technology in the power distribution network live working training and application prospect.

To investigate the influence of registration based on different reference markers on the displacement of the geometry consisted of all clips in the cavity for external-beam partial breast irradiation at moderate deep inspiration breath holding assisted by active breathing control device.Twenty-seven early stage breast cancer patients feasible for external beam partial breast irradiation (EB-PBI) were selected. The patients undertaken three-dimensional computed tomography (3DCT) simulation scan at moderate deep inspiration breath holding (mDIBH) assisted by active breathing control device, and two sets of mDIBH CT images were got and transferred to the Pinnacle 3 planning system. All of the silver clips were delineated and a geometry consisted of all clips were generated. On the account of automatic registration of mDIBH CT images, manual registration was carried out based separately on the topside clip in the cavity, the labeled skin at anterior surface of the cavity at central level and the metal mark on the body surface near the cavity, then the displacements of center of the geometry in left-right (LR), anterior-posterior (AP) and superior-inferior (SI) directions based separately on the three registrations were measured.The displacements of center of the geometry in LR, AP and SI directions based on registration of the clips, the labeled skin and the metal mark were (0.61 ± 0.62)mm vs. (1.11 ± 1.21)mm vs. (1.31 ± 1.55)mm, (0.63 ± 0.59)mm vs. (0.92 ± 0.93)mm vs. (1.19 ± 1.24)mm and (0.91 ± 0.96)mm vs. (2.13 ± 2.12)mm vs. (1.93 ± 1.55)mm, respectively. Compared the displacements of center of the geometry in the same direction between the three registrations, significant differences were found only in SI direction between clip registration and skin registration, clip registration and mark registration (t = 5.045, 7.210 and P = 0.025, 0.007) . Compared the displacements of center of the geometry between three dimensional directions for each reference registration, there was no significant difference (all P0.05).When EB-PBI is carried out in state of mDIBH, measurement of the intrafraction displacement based on registration of the clip in the cavity is a reasonable selection. Otherwise, excessive margin enlargement of PTV in SI direction will be generated if the regional skin or metal mark is selected as registration reference.

This paper presents a lumped equivalent circuit model of the nonreciprocal magnetoelectric tunable microwave band-pass filter. The reciprocal coupled-line circuit is based on the converse magnetoelectric effect of magnetoelectric composites, includes the electrical tunable equivalent factor of the piezoelectric layer, and is established by the introduced lumped elements, such as radiation capacitance, radiation inductance, and coupling inductance, according to the transmission characteristics of the electromagnetic wave and magnetostatic wave in an inverted-L-shaped microstrip line and ferrite slab. The nonreciprocal transmission property of the filter is described by the introduced T-shaped circuit containing controlled sources. Finally, the lumped equivalent circuit of a nonreciprocal magnetoelectric tunable microwave band-pass filter is given and the lumped parameters are also expressed. When the deviation angles of the ferrite slab are respectively 0° and 45°, the corresponding magnetoelectric devices are respectively a reciprocal device and a nonreciprocal device. The curves of S parameter obtained by the lumped equivalent circuit model and electromagnetic simulation are in good agreement with the experimental results. When the deviation angle is between 0° and 45°, the maximum value of the S parameter predicted by the lumped equivalent circuit model is in good agreement with the experimental result. The comparison results of the paper show that the lumped equivalent circuit model is valid. Further, the effect of some key material parameters on the performance of devices is predicted by the lumped equivalent circuit model. The research can provide the theoretical basis for the design and application of nonreciprocal magnetoelectric tunable devices.

Infusion phlebitis is the most common side effect of clinical intravenous drug therapy and several clinical studies have demonstrated that anisodamine can effectively prevent the occurrence of infusion phlebitis. This study was designed to investigate effects of anisodamine on the expressions of vascular endothelial growth factor (VEGF) and intercellular adhesion molecule 1 (ICAM-1) in a rabbit model of infusion phlebitis and to analyze the mechanisms of anisodamine effect on the prevention and treatment of experimental infusion phlebitis.Twenty-four specific pathogen-free male Japanese white rabbits were randomly assigned to the control group, the model group, the magnesium sulfate group and the anisodamine group. The rabbit model of infusion phlebitis, induced by intravenous administration, was established and expressions of VEGF and ICAM-1 were determined and contrasted with the control group treated with normal saline. We evaluated expression by histopathology, immunohistochemistry, reverse transcription-polymerase chain reaction, and Western blotting assay.Pathohistological changes of the model group were observed, such as loss of venous endothelial cells, inflammatory cell infiltration, edema and thrombus. The magnesium sulfate group and the anisodamine group showed significant protective effects on vascular congestion, inflammatory cell infiltration, proliferation, swelling of endothelium and perivascular hemorrhage. The model group showed the highest expressions of VEGF and ICAM-1 of the four groups (P0.01). On the contrary, anisodamine alleviated the inflammatory damage by significantly reducing the expressions of VEGF and ICAM-1 compared with the model group (P0.01). There was no significant difference in the expressions of VEGF and ICAM-1 between the magnesium sulfate group and the anisodamine group (P0.05).Anisodamine alleviates inflammatory damage by significantly reducing the expressions of VEGF and ICAM-1, and shows significant protective effects in an animal model of infusion phlebitis.

To explore the overlap ratio of the target volume in different respiratory statuses of active breath control (ABC) and their differences during external-beam partial breast irradiation (EB-PBI), and from the perspective of target volume overlap to determine the influence of the ABC-assisted breathing condition on intra-fractional target movement of EB-PBI.The patients, who received breast-conserving surgery with silver clips marked at the margins of the cavity and were suitable for EB-PBI, were immobilized on the breast bracket to undertake CT simulation assisted by ABC device, six sets of CT simulation images including two sets of image in state of moderate deep inspiration breathing control (mDIBH), two sets of images in state of free breath (FB) and two sets of images in state of deep expiration breathing control (DEBH) were obtained. The six sets of images were transferred to Pinnacle(3) treatment planning system (TPS), then automatic fusion and registration between two sets of mDIBH images, two sets of FB images, two sets of DEBH images and mDIBH image and DEBH image were achieved separately. Thereafter, the overlap ratios of GTV with GTV, CTV with CTV, PTV with PTV were calculated by the Pinnacle(3) TPS. The differences between the overlap ratios of the three kinds of targets in the same registered image and the difference between the overlap ratios of the same kind of target in the different registered images were statistically analyzed using statistical package of SPSS 11.5.Based on mDIBH/mDIBH registration, the overlap ratios of GTV/GTV, CTV/CTV and PTV/PTV were (83.54 ± 11.41)%, (93.00 ± 6.49)%, and (95.26 ± 4.90)%, respectively, and the differences of the overlap ratios between GTV/GTV and CTV/CTV, GTV/GTV and PTV/PTV were all statistically significant (P0.05), but statistically not significant between CTV/CTV and PTV/PTV (P0.05). Based on FB/FB registration, the overlap ratios of GTV/GTV, CTV/CTV and PTV/PTV were (72.55 ± 29.10)%, (89.36 ± 9.53)% and (92.47 ± 7.25)%, respectively, and the differences of the overlap ratios between GTV/GTV and CTV/CTV, CTV/CTV and PTV/PTV were all not statistically significant (P0.05), but statistically significant between GTV/GTV and PTV/PTV (P0.05). Based on DEBH/DEBH registration, the overlap ratios of GTV/GTV, CTV/CTV and PTV/PTV were (79.48 ± 22.31)%, (92.83 ± 6.77)% and (95.05 ± 4.81)%, respectively, and the differences of the overlap ratios between GTV/GTV and CTV/CTV (P = 0.000), CTV/CTV and PTV/PTV (P = 0.037), GTV/GTV and PTV/PTV (P = 0.000) were statistically all significant (P = 0.000). The differences of the overlap ratios of GTV/GTV, CTV/CTV, and PTV/PTV (P = 0.000) between mDIBH/mDIBH and DEBH/DEBH, mDIBH/mDIBH and FB/FB, FB/FB and DEBH/DEBH were all statistically significant (P = 0.000), and not statistically significant between mDIBH/mDIBH and mDIBH/DEBH, FB/FB and mDIBH/DEBH.During the delivering of EB-PBI assisted by ABC, the intra-fractional overlap ratios of the target volume between the same breathing state is increasing in the order of GTV/GTV → CTV/CTV → PTV/PTV. The difference of the overlap ratios of the target volumes between mDIBH and mDIBH, FB and FB, DEBH and DEBH is not significant, and the overlap ratios of PTV/PTV in the three breathing statuses of mDIBH, FB and DEBH reaches a higher level. Therefore, from the perspective of target volume overlap, if the setup error is corrected online before delivering, the necessity of breathing control during delivering of EB-PBI is worthy discussing.

We report on the prenatal diagnosis and genetic analysis of a 48,XXYY fetus. A 28-year-old woman was referred for amniocentesis at 18 weeks' gestation because of advanced paternal age. Quantitative-fluorescence polymerase chain reaction (QF-PCR) with small tandem repeat (STR) markers rapidly detected the sex chromosome polysomy from amniotic fluid cells. This abnormality appeared to arise from successive non-disjunction during paternal meiosis I and meiosis II. Cytogenetic analysis revealed a karyotype of 48,XXYY. This case adds to the evidence that an age-related increase in sex chromosomal aneuploidies occurs in sperm. This case also shows that QF-PCR assays can provide rapid prenatal diagnosis of numerical sex chromosome aneuploidy.

To explore the role of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of MMP-2 (TIMP-2) in the pathogenesis, development and prognosis of gestational trophoblastic disease (GTD).In situ hybridization and immunohistochemistry were utilized for MMP-2/TIMP-2 mRNA and protein detection in normal chorion of women with early gestation, hydatidiform mole, invasive mole, or choricarcinoma.The results revealed that specific staining for mRNA and protein of MMP-2 and the expression of TIMP-2 was reduced in normal chorion of early gestation. In GTD ranging from hydatidiform mole, invasive mole to choricarcinoma, MMP-2 expression tended to increase while TIMP-2 expression underwent an invert change. The positivity rate of MMP-2 and TIMP-2 in gestational trophoblastic tumor group was higher than that of the normal chorion of early gestation group and hydatiform mole group (P0.05 and P0.001, respectively).A disrupted balance between the activation and inhibition of MMP-2 plays a critical role in the pathogenesis, progression and metastasis of GTD.