A high resolution reaction microscope with universal two-region time-focusing method

This paper presents a novel reaction microscope designed for ion-atom collision investigations, established at the Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China. Its time-of-flight (TOF) spectrometer employs an innovative flight-time focusing method consisting of two acceleration regions, providing optimal time focusing conditions for charged fragments with diverse initial velocities. The TOF spectrometer's axis intentionally tilts by 12° relative to the ion beam direction, preventing potential obstructions from the TOF grid electrodes. The introduced focusing method allows for a flexible time-focusing TOF spectrometer design without restricting the length ratio of the two regions. In addition, this configuration in our case significantly suppresses noise on the recoil ion detector produced by residual gas in the ion beam trajectory, which is a considerable challenge in longitudinal spectrometers. In a test experiment on the single electron capture reaction involving 62.5 keV/u He2+ ions and a helium atomic beam, the recoil longitudinal momentum resolution achieved 0.068 atomic units. This novel configuration and successful test run show excellent precision for ion-atom collision studies.

[Effect and mechanism of human adipose-derived stem cell exosomes on diabetic peripheral neuropathy]

Objective: To investigate the changes of artemin protein expression in diabetic peripheral neuropathy (DPN) and to explore the regulatory effect of human adipose-derived stem cell (ADSC) exosomes on the change of artemin protein expression. Methods: This research was a prospective observational clinical research combined with experimental research. Thirteen DPN patients (9 males and 4 females, aged 32 to 68 years) who were admitted to the First Affiliated Hospital of Air Force Medical University (hereinafter referred to as our hospital) from May 2022 to October 2023 and met the inclusion criteria were selected as DPN group, and 5 non-diabetes patients (4 males and 1 female, aged 29 to 61 years) who were admitted to our hospital in the same period of time and met the inclusion criteria were selected as control group. The toe nerve or sural nerve tissue in the abandoned tissue after debridement or amputation of patients in the two groups was collected. The pathological changes of nerve tissue were observed after hematoxylin-eosin staining; the protein expressions of S100β and artemin in nerve tissue were observed after immunofluorescence staining, and the artemin protein expression was quantified; the protein and mRNA expressions of artemin were detected by Western blotting and real-time fluorescent quantitative reverse transcription polymerase chain reaction, respectively (the sample number in DPN group and control group was 13 and 5, respectively). Twelve male C57BL/6 mice aged 3 to 5 days were collected to isolate Schwann cells, and the cells were divided into conventional culture group cultured routinely, high glucose alone group (cultured with high concentration of glucose solution only), and high glucose+exosome group (cultured with high concentration of glucose solution and extracted human ADSC exosomes). After 24 hours of culture, the cell proliferation activity was detected by cell counting kit 8 (n=6). After 48 hours of culture, the protein expression of artemin was detected by Western blotting (n=3). Results: Compared with those in control group, the neural supporting cells decreased and the inflammatory cells increased in the nerve tissue of patients in DPN group, showing typical manifestations of nerve injury. Immunofluorescence staining showed that compared with those in control group, the nuclei was more, and the protein expression of S100β was lower in nerve tissue of patients in DPN group. The protein expression of artemin in nerve tissue of patients in DPN group was 71±31, which was significantly lower than 1 729±62 in control group (t=76.92, P<0.05). Western blotting detection showed that the protein expression of artemin in nerve tissue of patients in DPN group was 0.74±0.08, which was significantly lower than 0.97±0.06 in control group (t=5.49, P<0.05). The artemin mRNA expression in nerve tissue of patients in DPN group was significantly lower than that in control group (t=7.65, P<0.05). After 24 hours of culture, compared with that in conventional culture group, the proliferation activities of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the proliferation activity of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). After 48 hours of culture, compared with those in conventional culture group, the protein expressions of artemin of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the protein expression of artemin of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). Conclusions: The protein expression of artemin in nerve tissue of DPN patients is lower than that in normal nerve tissue, which may be related to the reduction of proliferation activity of Schwann cells by high glucose. Human ADSC exosomes may improve the proliferation activity of Schwann cells by increasing artemin protein expression, thereby delaying the progression of DPN.

Theoretical and experimental studies on channel impulse response of short-range non-line-of-sight ultraviolet communications

A theoretical channel impulse response (CIR) model of short-range non-line-of-sight (NLOS) ultraviolet communications (UVC) in noncoplanar geometry under the single-scatter condition is proposed. Simulation results obtained from the widely accepted Monte-Carlo (MC)-based channel model of NLOS UVC are provided to verify corresponding theoretical results obtained from the proposed theoretical single-scatter CIR model. Additionally, an outdoor experiment with a light-emitting diode (LED) as the light source is first designed to measure the channel step response of NLOS UVC and to further validate the proposed theoretical single-scatter CIR model. By varying the different parameters of the transmitter and the receiver, such as the baseline range, the inclination angle, the azimuth angle, the beam divergence angle, and the field-of-view angle, the results of the proposed theoretical single-scatter CIR model and the MC-based channel model are exhibited and further analyzed in detail. Results indicate that the computational time cost by the proposed theoretical single-scatter CIR model is decreased to less than 0.6% of the MC-based one with comparable accuracy in assessing the temporal characteristics of NLOS UVC channels. Additionally, theoretical results obtained from the proposed theoretical single-scatter CIR model manifest satisfactory agreement with corresponding experimental measurements.

Application of Electrocardiogram Localization during Peripherally Inserted Central Catheter Line Insertion into the Persistent Left Superior Vena Cava of Neonates

BACKGROUND

 Most neonates with persistent left superior vena cava (PLSVC) have no clinical symptoms or hemodynamic changes, and this anomaly is only found during cardiac catheterization, pacemaker implantation, or central venous catheterization. Electrocardiogram (ECG) localization is helpful for the application of the peripherally inserted central catheter (PICC) technique in neonates with PLSVC.

OBJECTIVE

 To explore the characteristic waveforms of the P wave when a PICC under ECG localization is applied in neonates with PLSVC.

STUDY DESIGN

 The observation and management strategies for the P wave changes during catheter insertion (CI) of two neonates with PLSVC admitted to our institution between January and July 2020, who underwent PICC line insertion, were summarized.

RESULTS

 The characteristic P wave changes in two children with a PICC line inserted via the PLSVC were observed. When a wide inverted P wave appeared on ECG, the catheter was immediately withdrawn by 0.5 cm, a bidirectional P wave gradually appeared and then disappeared. After that, the catheter was further withdrawn by 0.5 cm. After catheterization, the optimal position of the PICC was confirmed by X-ray photography and bedside B-ultrasound. The PICC line was removed as scheduled after indwelling for 18 and 29 days, respectively, in the two cases, and no PICC-related complications occurred during indwelling.

CONCLUSION

 The characteristic P wave changes on ECG during CI provide important clinical reference values for the application of the PICC technique under ECG localization in neonates with PLSVC.

KEY POINTS

· Electrocardiogram localization.. · Peripherally inserted central catheter.. · Persistent left superior vena cava..

[Research advances on the role of Schwann cells in diabetic peripheral neuropathy]

Diabetic peripheral neuropathy (DPN) is one of the common chronic complications of diabetes, resulting in neuropathy of spinal nerve, cranial nerve, and vegetative nerve. Diabetic distal symmetric multiple neuropathy is the most representative lesion of DPN, including symptoms of bilateral limbs pain, numbness, and paresthesia, etc. DPN is one of the main reasons causing diabetic foot ulcer (DFU). Schwann cells (SCs) are the primary glia cells of the peripheral nervous system, which play very important role in repairing after nerve injury. As the target cells of chronic hyperglycemia, SCs' functions, including the formation of myelin sheath, the secretion of neurotrophic factors, energy supplying for the axon, and the guidance of axon regeneration, etc., are damaged under the action of high glucose. The destroyed functions of SCs can inhibit the repair of damaged nerves and accelerate the progress of DPN. Therefore, if the damage of high glucose to SCs can be effectively reduced, it will provide a new way for the treatment of DPN and DFU and reduce the morbidity of DFU. This review focuses on the function of SCs and its relationship with DPN.

[Effects of the anterolateral thigh chimeric perforator flaps in repairing complex wounds of foot and ankle]

Objective: To investigate the effects of anterolateral thigh chimeric perforator flap in repairing complex wounds of foot and ankle. Methods: A retrospective observational study was conducted. From May 2018 to June 2022, 23 patients who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University to repair complex wounds of foot and ankle with anterolateral thigh chimeric perforator flaps, including 15 males and 8 females, aged from 20 to 66 years. The wounds were all accompanied by bone exposure and defects, and were complicated with varying degrees of infection. All patients underwent debridement and continuous vacuum sealing drainage treatment for 1 week in stage Ⅰ, with the skin and soft tissue defect area after debridement being 10 cm×5 cm to 22 cm×7 cm. In stage Ⅱ, the anterolateral thigh chimeric perforator flap was used to cover the defective wound, of which the muscle flap was used to fill the deep invalid cavity of the ankle joint or cover bone and internal fixation exposures, and the skin flap was used to cover the superficial wound, with the area of the skin flap ranging from 11 cm×6 cm to 23 cm×8 cm, and the area of the muscle flap ranging from 4.0 cm×2.5 cm to 8.0 cm×5.0 cm. The survival of the flap was observed after operation. During follow-up, the color, texture, appearance, and complications of the flap were observed, the function of ankle joint and its range of dorsiflexion motion and plantar flexion motion were measured, and the scar hyperplasia and muscular hernia in donor area were observed. Results: Ecchymosis and epidermal necrosis occurred at the tip of the flap in 1 patient on 5 days after operation and healed after dressing change for 1 week; the other flaps of patients survived successfully. After 6 to 40 months of follow-up, the color, texture, and shape of flaps were good, but 1 patient was not satisfied with the shape of the flap because of flap swelling; the ankle joint movement was basically normal, the dorsiflexion motion was 15-30°, and the plantar flexion motion was 20-45°; the scar hyperplasia in the donor area of the flap was not obvious, and no muscular hernia occurred. Conclusions: The anterolateral thigh chimeric perforator flap can effectively fill the deep invalid cavity of ankle joint and cover the superficial wound at the same time, with minimal damage to the donor site. So it is an ideal flap for repairing the complex wounds of foot and ankle.

Clinical evaluation of hysterectomy for the treatment of invasive mole in Southern Vietnam

OBJECTIVE

This study aimed to determine the rate of salvage chemotherapy and review associated factors in invasive mole patients treated by primary or delayed hysterectomy.

PATIENTS AND METHODS

This study was carried out at the Tu Du Hospital, where a total of 189 patients were diagnosed with invasive mole based on histologic examination by hysterectomy between 01/2016 to 12/2020. We used the life table method to estimate the cumulative rate. We applied the Cox proportional hazard model to determine the factors associated with the need for salvage chemotherapy.

RESULTS

At 12-month follow-up, 47 patients had required salvage chemotherapy. The incidence was 24.87% (95% CI: 18.88-31.66). Applying the multivariate model, prophylactic chemotherapy (HR = 2.75, 95% Cl: 1.20-6.30) and two weeks postoperative hCG value greater than 1,900 mIU/mL (HR = 4.30, 95% Cl: 2.08-8.87) increased the risk of requiring salvage chemotherapy. Postoperative chemotherapy decreased the risk of requiring salvage chemotherapy (HR = 0.43, 95% Cl: 0.22-0.83).

CONCLUSIONS

Hysterectomy can be considered safe and effective in treating invasive mole patients. Although patients were treated by hysterectomy, 24.87% of patients needed salvage chemotherapy to achieve remission. This study affirms the malignant nature of invasive mole, a subtype of gestational trophoblastic neoplasia (GTN). It is not purely a local invasion of molar villi. Postoperative chemotherapy plays an essential role in reducing the risk of requiring salvage chemotherapy.

First CLAS12 Measurement of Deeply Virtual Compton Scattering Beam-Spin Asymmetries in the Extended Valence Region

Deeply virtual Compton scattering (DVCS) allows one to probe generalized parton distributions describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6 GeV electron beam scattering from unpolarized protons. The results greatly extend the Q^{2} and Bjorken-x phase space beyond the existing data in the valence region and provide 1600 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.

[A prospective randomized controlled study of antibiotic bone cement in the treatment of diabetic foot ulcer]

Objective: To investigate the clinical effects and related mechanism of antibiotic bone cement in treating diabetic foot ulcer (DFU). Methods: A prospective randomized controlled study was conducted. From August 2020 to August 2022, 24 patients with DFU who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University. According to the block randomization, the patients were divided into 2 groups, with 12 patients in each group. In antibiotic bone cement group, there were 7 male and 5 female patients, aged (64±8) years, with the ulcer area of (41±21) cm2. In silver sulfadiazine group, there were 8 male and 4 female patients, aged (62±8) years, with the ulcer area of (38±19) cm2. Under the condition of ensuring the patency of at least one main inferior genicular artery in each patient, the continuous vacuum sealing drainage was performed for 3-5 days after thorough debridement. Thereafter, the wounds in antibiotic bone cement group were treated with gentamicin-laden bone cement, and the wounds in silver sulfadiazine group were treated with silver sulfadiazine cream for dressing change. After 3 weeks of dressing change, the wound was covered with split-thickness skin graft from the lateral thigh on the affected side. Before debridement and after 3 weeks of dressing change, the blood flow intensities of wound tissue and normal skin tissue in foot were measured using laser Doppler flowmeter, and then, the percentage of relative blood flow intensity of wound and the change rate of blood flow intensity were calculated. After 3 weeks of dressing change, the wound margin tissue was taken, the number of CD31-positive neovascular and the vascular morphology were observed and detected by immunohistochemical staining, the morphology of blood vessels surrounded by CD31 and α-smooth muscle actin (α-SMA) double-positive cells was observed by immunofluorescence staining, the cell proliferation activity was evaluated by immunofluorescence staining (denoted as the ratio of Ki67 positive cells), and the protein expression of vascular endothelial growth factor receptor 2 (VEGFR2) was detected by Western blotting. The skin graft survival was observed 3-5 days after skin grafting, and the wound healing time was recorded. Data were statistically analyzed with independent sample t test and Fisher's exact probability test. Results: The percentages of relative blood flow intensity of wounds of patients before debridement were similar between the two groups (P>0.05). After 3 weeks of dressing change, the percentage of relative blood flow intensity of wounds and the change rate of blood flow intensity of patients in antibiotic bone cement group were (44.7±2.0)% and (129±12)%, respectively, which were significantly higher than (28.3±1.2)% and (41±8)% in silver sulfadiazine group (with t values of 24.15 and 20.97, respectively, P<0.05). After 3 weeks of dressing change, compared with those in silver sulfadiazine group, the number of CD31-positive neovascular in the wound margin tissue of patients in antibiotic bone cement group was significantly increased (t=33.81, P<0.05) with larger diameter and more regular arrangement, the vascular wall continuity surrounded by CD31 and α-SMA double-positive cells was better, and the ratio of Ki67 positive cells and protein expression of VEGFR2 were significantly increased (with t values of 40.97 and 47.38, respectively, P<0.05). On post skin grafting day 3-5, all the patients in antibiotic bone cement group and 8 patients in silver sulfadiazine group had good skin graft survival, while 4 patients in silver sulfadiazine group showed spotted/patchy skin graft necrosis, which were cured after corresponding treatment. The wound healing time of patients in antibiotic bone cement group was (47.1±2.9) d, which was significantly shorter than (58.8±2.3) d in silver sulfadiazine group (t=10.86, P<0.05). Conclusions: Compared with silver sulfadiazine, clinical application of antibiotic bone cement for treating DFU has the characteristics of accelerating wound healing and better reconstruction of local blood flow, which may be closely related to the fact that antibiotic bone cement promoted the local angiogenesis effectively in the wound through enhancing the expression of VEGFR2.

Chimeric Antigen Receptor-Natural Killer Cells: A New Breakthrough in the Treatment of Solid Tumours

Natural killer (NK) cells can quickly and directly eradicate tumour cells without recognising tumour-specific antigens. NK cells also participate in immune surveillance, which arouses great interest in the development of novel cancer therapies. The chimeric antigen receptor (CAR) family is composed of receptor proteins that give immune cells extra capabilities to target specific antigen proteins or enhance their killing effects. CAR-T cell therapy has achieved initial success in haematological tumours, but is prone to adverse reactions, especially with cytokine release syndrome in clinical applications. Currently, CAR-NK cell therapy has been shown to successfully kill haematological tumour cells with allogeneic NK cells in clinical trials without adverse reactions, proving its potential to become an off-the-shelf product with broad clinical application prospects. Meanwhile, clinical trials of CAR-NK cells for solid tumours are currently underway. Here we will focus on the latest advances in CAR-NK cells, including preclinical and clinical trials in solid tumours, the advantages and challenges of CAR-NK cell therapy and new strategies to improve the safety and efficacy of CAR-NK cell therapy.

[Effects of exosomes from hepatocyte growth factor-modified human adipose mesenchymal stem cells on full-thickness skin defect in diabetic mice]

Objective: To investigate the effects and mechanism of exosomes from hepatocyte growth factor (HGF)-modified human adipose mesenchymal stem cells (ADSCs) on full-thickness skin defect wounds in diabetic mice. Methods: The experimental study method was adopted. Discarded adipose tissue of 3 healthy females (10-25 years old) who underwent abdominal surgery in the Department of Plastic Surgery of First Affiliated Hospital of Air Force Medical University from February to May 2021 was collected, and primary ADSCs were obtained by collagenase digestion method and cultured for 7 days. Cell morphology was observed by inverted phase contrast microscope. The ADSCs of third passage were transfected with HGF lentivirus and cultured for 5 days, and then the fluorescence of cells was observed by imaging system and the transfection rate was calculated. The exosomes of ADSCs of the third to sixth passages and the HGF transfected ADSCs of the third to sixth passages were extracted by density gradient centrifugation, respectively, and named, ADSC exosomes and HGF-ADSC exosomes. The microscopic morphology of exosomes was observed by transmission electron microscopy, and the positive expressions of CD9, CD63, and CD81 of exosomes were detected by flow cytometry, respectively. Twenty-four 6-week-old male Kunming mice were selected to make the diabetic models, and full-thickness skin defect wounds were made on the backs of mice. According to the random number table method, the mice were divided into phosphate buffer solution (PBS) group, HGF alone group, ADSC exosome alone group, and HGF-ADSC exosome group, with 6 mice in each group, and treated accordingly. On post injury day (PID) 3, 7, 10, and 14, the wounds were observed and the wound healing rate was calculated; the blood flow intensity of wound base was detected by Doppler flowmeter and the ratio of relative blood flow intensity on PID 10 was calculated. On PID 10, the number of Ki67 positive cells in wounds was detected by immunofluorescence method, and the number of new-vascularity of CD31 positive staining and tubular neovascularization in the wounds was detected by immunohistochemistry method; the protein expressions of protein endothelial nitric oxide synthase (eNOS), phosphatidylinositol 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), protein kinase B (Akt) and phosphorylated Akt (p-Akt) in wounds were detected by Western blotting, and the ratios of p-PI3K to PI3K and p-Akt to Akt were calculated. On PID 14, the defect length and collagen regeneration of wound skin tissue were detected by hematoxylin and eosin staining and Masson staining, respectively, and the collagen volume fraction (CVF) was calculated. The number of samples is 3 in all cases. Data were statistically analyzed with repeated measurement analysis of variance, one-way analysis of variance, and Tukey test. Results: After 7 days of culture, the primary ADSCs were spindle shaped and arranged in vortex shape after dense growth. After 5 days of culture, HGF transfected ADSCs of the third passage carried green fluorescence, and the transfection rate was 85%. The ADSC exosomes and HGF-ADSC exosomes were similar in microscopic morphology, showing vesicular structures with an average particle size of 103 nm and 98 nm respectively, and both were CD9, CD63, and CD81 positive. On PID 3, the wounds of mice in the 4 groups were all red and swollen, with a small amount of exudate. On PID 7, the wounds of HGF-ADSC exosome group were gradually reduced, while the wounds of the other three groups were not significantly reduced. On PID 10, the wounds in the 4 groups were all reduced and scabbed. On PID 14, the wounds in HGF-ADSC exosome group were basically healed, while the residual wounds were found in the other three groups. On PID 3, the healing rates of wounds in the four groups were similar (P>0.05); On PID 7 and 10, the wound healing rates in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 13.11, 13.11, 11.89, 12.85, 11.28, and 7.74, respectively, all P<0.01); on PID 14, the wound healing rate in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 15.50, 11.64, and 6.36, respectively, all P<0.01). On PID 3, there was no obvious blood supply in wound base of mice in the 4 groups. On PID 7, microvessels began to form in the wound base of HGF-ADSC exosome group, while the wound base of the other three groups was only congested at the wound edge. On PID 10, microvessel formation in wound base was observed in the other 3 groups except in PBS group, which had no obvious blood supply. On PID 14, the blood flow intensity of wound base in HGF-ADSC exosome group was stronger than that in the other 3 groups, and the distribution was uniform. On PID 10, the ratio of wound base relative blood flow intensity in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 23.73, 19.32, and 9.48, respectively, all P<0.01); The numbers of Ki67-positive cells and new-vascularity of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 19.58, 18.20, 11.04, 20.68, 13.79, and 8.12, respectively, P<0.01). On PID 10, the protein expression level of eNOS of wounds in HGF-ADSC exosome group was higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 53.23, 42.54, and 26.54, respectively, all P<0.01); the ratio of p-PI3K to PI3K and the ratio of p-Akt to Akt of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 16.11, 11.78, 6.08, 65.54, 31.63, and 37.86, respectively, P<0.01). On PID 14, the length of skin tissue defect in the wounds of HGF-ADSC exosome group was shorter than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 20.51, 18.50, and 11.99, respectively, all P<0.01); the CVF of wounds in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group and ADSC exosome alone group (with q values of 31.31, 28.52, and 12.35, respectively, all P<0.01). Conclusions: Human HGF-ADSC exosomes can significantly promote wound healing in diabetic mice by increasing neovascularization in wound tissue, and the mechanism may be related to the increased expression of eNOS in wounds by activating PI3K/Akt signaling pathway.

Modular Assembly of MXene Frameworks for Noninvasive Disease Diagnosis via Urinary Volatiles

Volatile organic compounds (VOCs) in urine are valuable biomarkers for noninvasive disease diagnosis. Herein, a facile coordination-driven modular assembly strategy is used for developing a library of gas-sensing materials based on porous MXene frameworks (MFs). Taking advantage of modules with diverse composition and tunable structure, our MFs-based library can provide more choices to satisfy gas-sensing demands. Meanwhile, the laser-induced graphene interdigital electrodes array and microchamber are laser-engraved for the assembly of a microchamber-hosted MF (MHMF) e-nose. Our MHMF e-nose possesses high-discriminative pattern recognition for simultaneous sensing and distinguishing of complex VOCs. Furthermore, with the MHMF e-nose being a plug-and-play module, a point-of-care testing (POCT) platform is modularly assembled for wireless and real-time monitoring of urinary volatiles from clinical samples. By virtue of machine learning, our POCT platform achieves noninvasive diagnosis of multiple diseases with a high accuracy of 91.7%, providing a favorable opportunity for early disease diagnosis, disease course monitoring, and relevant research.

What are the ideal systolic and diastolic blood pressure which do not injure the intima of iliac and coronary arteries?

 

For patients with coronary artery disease, hypertension (HTN) is a major risk factor. How could uncontrolled HTN start atherosclerosis? In our prior research, laminar flow in coronary arteries prevented the formation of plaques while turbulent flow injured the intima and triggered atherosclerosis. In this present study our question was: Which blood pressure (BP) level is optimal in not producing turbulence and so not injuring the intima?

Methods

At first, a systolic BP&lt;120mmHg and diastolic BP&lt;75mmHg) were arbitrarily set as controlled (group A) while a BP of &gt;160/105mmHg as uncontrolled (group B). All patients underwent a dynamic coronary angiogram recorded at 15 images/second or 0.06 seconds per image. The first image was of the index artery completely filled with contrast. In subsequent images the blood in white color moved in over a background of black contrast (Figure 1A). In 1B, 0.06 seconds later, the blood arrived at the mid segment (white arrow). In 1C, the flood moved forward, however there was darker contrast hanging at the mid segment, marking the location of collision from the retrograde against the antegrade flow (white arrow). The reason was that in uncontrolled BP the contraction of the left ventricle was stronger so in systole, the coronary blood could reverse its course, run on a retrograde direction, collide against the antegrade flow and create turbulence (1C).

At the end, before deploying a vascular closure device, an iliac angiogram was performed. In Figure 2, on a black background of contrast, the blood in white color moved forward with a pointed tip of laminar flow. 0.06 seconds later, the laminar tip was stopped abruptly with all the layers recoiling on each other like a falling stack of dominoes. In the next image. a large swirl of disorganized mixing of blood and contrast suggested the presence of turbulence caused by the collision.

The data to be collected were (1) the duration of the antegrade and retrograde flow, (2) duration of the collision (turbulence at the collision site)

Results

In the group A (BP &lt;120/75 mmHg), 90% of 20 patients had no retrograde flow nor collision in the iliac and short collision in coronary arteries (&lt;0.12 secs). In 30 patients of group B (BP &gt;160/105 mmHg), the duration of retrograde flow and collision in the iliac artery were prolonged at &gt;0.24 msecs. In the coronary arteries, the duration was prolonged at 0.18 msecs (all p&lt;0.05 compared with group A). These locations of turbulence correlated with the location of plaques in our prior studies.

Conclusion

In patients with uncontrolled HTN, the retrograde flow was prolonged, and the turbulence was intense. In contrary, for patients with controlled BP, there was no retrograde flow and weaker collision in coronary arteries. The results suggest that a BP of &lt;120/75 mmHg may not trigger the atherosclerotic process. New clinical trials with larger number of patients should be performed in search for the lowest ideal blood pressure.

Funding Acknowledgement

Type of funding sources: None.

Single-collision-induced path loss model of reflection-assisted non-line-of-sight ultraviolet communications

By considering both scattering and reflection events as collision-induced events (CIEs), an analytical path loss model of reflection-assisted non-line-of-sight (NLOS) ultraviolet communications (UVC) is proposed with single CIE incorporated, which refers to the single-collision-induced (SCI) path loss model. More specifically, the analytical expressions of the received optical energy resulting from single-scatter and single-reflection events in reflection-assisted NLOS UVC are respectively derived. Then, in terms of those two expressions, the expression of the proposed SCI path loss model is obtained. Finally, Monte-Carlo (MC) simulations and experimental results are given to verify the correctness and effectiveness of the proposed SCI path loss model. The results manifest that the proposed SCI path loss model can work well in both coplanar and noncoplanar geometry of the reflection-assisted NLOS UVC.

[Clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns]

Objective: To explore the clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns. Methods: A retrospective observational study was conducted. From May 2018 to April 2021, 11 patients with cervical cicatrix contracture deformity after burns who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University, including 3 males and 8 females, aged 5 to 46 years, with a course of cervical cicatrix contracture deformity of 5 months to 8 years. The degree of cervical cicatrix contracture deformity was degree Ⅰ in one patient, degree Ⅱ in nine patients, and degree Ⅲ in one patient. In the first stage, according to the sizes of neck scars, one rectangular skin and soft tissue expander (hereinafter referred to as expander) with rated capacity of 200 to 600 mL was placed in the back. The expansion time was 4 to 12 months with the total normal saline injection volume being 3.0 to 3.5 times of the rated capacity of expander. In the second stage, free expanded thoracodorsal artery perforator flaps with areas of 10 cm×7 cm to 24 cm×13 cm were cut out to repair the wounds with areas of 9 cm×6 cm to 23 cm×12 cm which was formed after cervical cicatectomy. The main trunk of thoracodorsal artery and vein were selected for end-to-end anastomosis with facial artery and vein, and the donor sites were directly closed. The survival of flaps and healing of flap donor sites were observed on the 14th day post surgery. The appearances and cicatrix contracture deformity of the flaps, recovery of cervical function, and scar hyperplasia of donor sites were followed up. Results: On the 14th day post surgery, the flaps of ten patients survived, while ecchymosis and epidermal necrosis occurred in the center of flap of one patient and healed 2 weeks after dressing change. On the 14th day post surgery, the flap donor sites of 11 patients all healed well. During the follow-up of 6-12 months post surgery, the flaps of ten patients were similar to the skin around the recipient site in texture and color, while the flap of one patient was slightly swollen. All of the 11 patients had good recovery of cervical function and no obvious scar hyperplasia nor contracture in the flaps or at the donor sites. Conclusions: Application of expanded thoracodorsal artery perforator flaps can restore the appearance and function of the neck, and cause little damage to the donor site in reconstructing the cervical cicatrix contracture deformity after burns, which is worthy of clinical reference and application.

Modeling of ultraviolet propagation from air to human epidermis with wavelength range of 200-300 nm

Ultraviolet (UV) technology plays an important role in the fields of sterilization, disinfection, and short-range wireless optical communications. In this Letter, a theoretical model to determine the UV radiation intensity (UVRI) on human skin is put forward based on the Monte Carlo method, where the UV wavelength ranges from 200 to 300 nm. Meanwhile, the UVRI evaluation algorithm is provided to reproduce the simulation results. Furthermore, the penetration depth of UV radiation in the human epidermis is investigated, which can be used to assess whether UV radiation causes damage to human health. Simulation results coincide with the existing experimental results that the 222-nm UV radiation is harmless to humans at the given dose of 1.7 mJ/cm². This work provides theoretical guidelines for the power control of a UV system when humans are in the vicinity.

[Effects of exosomes from human adipose-derived mesenchymal stem cells on pulmonary vascular endothelial cells injury in septic mice and its mechanism]

Objective: To investigate the effects of exosomes from human adipose-derived mesenchymal stem cells (ADSCs) on pulmonary vascular endothelial cells (PMVECs) injury in septic mice and its mechanism. Methods: The experimental research method was adopted. The primary ADSCs were isolated and cultured from the discarded fresh adipose tissue of 3 patients (female, 10-25 years old), who were admitted to the First Affiliated Hospital of Air Force Medical University undergoing abdominal surgery, and the cell morphology was observed by inverted phase contrast microscope on the 5th day. The expressions of CD29, CD34, CD44, CD45, CD73, and CD90 of ADSCs in the third passage were detected by flow cytometry. The third to the fifth passage of ADSCs were collected, and their exosomes from the cell supernatant were obtained by differential ultracentrifugation, and the shape, particle size, and the protein expressions of CD9, CD63, tumor susceptibility gene 101 (TSG101), and β-actin of exosomes were detected, respectively, by transmission electron microscopy, nano-particle tracking analysis and Western blotting. Twenty-four adult male BALB/c mice were adopted and were divided into normal control group, caecal ligation perforation (CLP) alone group, and CLP+ADSC-exosome group with each group of 8 according to random number table (the same grouping method below) and were treated accordingly. At 24 h after operation, tumor necrosis factor (TNF-α) and interleukin 1β (IL-1β) levels of mice serum were detected by enzyme-linked immunosorbent assay, and lung tissue morphology of mice was detected by hematoxylin-eosin and myeloperoxidase staining, and the expression of 8-hydroxy-deoxyguanosine (8-OHdG) of mouse lung cells was detected by immunofluorescence method. Primary PMVECs were obtained from 1-month-old C57 mice regardless gender by tissue block method. The expression of CD31 of PMVECs was detected by immunofluorescence and flow cytometry. The third passage of PMVECs was co-cultured with ADSCs derived exosomes for 12 h, and the phagocytosis of exosomes by PMVECs was detected by PKH26 kit. The third passage of PMVECs were adopted and were divided into blank control group, macrophage supernatant alone group, and macrophage supernatant+ADSC-exosome group, with 3 wells in each group, which were treated accordingly. After 24 h, the content of reactive oxygen species in cells was detected by flow cytometry, the expression of 8-OHdG in cells was detected by immunofluorescence, and Transwell assay was used to determine the permeability of cell monolayer. The number of samples in above were all 3. Data were statistically analyzed with one-way analysis of variance and least significant difference t test. Results: The primary ADSCs were isolated and cultured to day 5, growing densely in a spindle shape with a typical swirl-like. The percentages of CD29, CD44, CD73 and CD90 positive cells of ADSCs in the third passage were all >90%, and the percentages of CD34 and CD45 positive cells were <5%. Exosomes derived from ADSCs of the third to fifth passages showed a typical double-cavity disc-like structure with an average particle size of 103 nm, and the protein expressions of CD9, CD63 and TSG101 of exosomes were positive, while the protein expression of β-actin of exosomes was negative. At 24 h after operation, compared with those in normal control group, both the levels of TNF-α and IL-1β of mice serum in CLP alone group were significantly increased (with t values of 28.76 and 29.69, respectively, P<0.01); compared with those in CLP alone group, both the content of TNF-α and IL-1β of mice serum in CLP+ADSC-exosome group was significantly decreased (with t values of 9.90 and 4.76, respectively, P<0.05 or P<0.01). At 24 h after surgery, the pulmonary tissue structure of mice in normal control group was clear and complete without inflammatory cell infiltration; compared with those in normal control group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP alone group were more obvious; compared with those in CLP alone group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP+ADSC-exosome group were significantly reduced. At 24 h after operation, endothelial cells in lung tissues of mice in 3 groups showed positive expression of CD31; compared with that in normal control group, the fluorescence intensity of 8-OHdG positive cells of the lung tissues of mice in CLP alone group was significantly increased, and compared with that in CLP alone group, the fluorescence intensity of 8-OHdG positive cells in the lung tissues of mice in CLP+ADSC-exosome group was significantly decreased. The PMVECs in the 3rd passage showed CD31 positive expression by immunofluorescence, and the result of flow cytometry showed that CD31 positive cells accounted for 99.5%. At 12 h after co-culture, ADSC-derived exosomes were successfully phagocytose by PMVECs and entered its cytoplasm. At 12 h after culture of the third passage of PMVECs, compared with that in blank control group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant alone group was significantly increased (t=15.73, P<0.01); compared with that in macrophage supernatant alone group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant+ADSC-exosome group was significantly decreased (t=4.72, P<0.01). At 12 h after culture of the third passage of PMVECs, and the 8-OHdG positive fluorescence intensity of PMVECs in macrophage supernatant alone group was significantly increased; and compared with that in blank control group, the 8-OHdG positive fluorescence intensity of PMVECs in macrophage+ADSC-exosome supernatant group was between blank control group and macrophage supernatant alone group. At 12 h after culture of the third passage PMVECs, compared with that in blank control group, the permeability of PMVECs monolayer in macrophage supernatant alone group was significantly increased (t=6.34, P<0.01); compared with that in macrophage supernatant alone group, the permeability of PMVECs monolayer cells in macrophage supernatant+ADSC-exosome group was significantly decreased (t=2.93, P<0.05). Conclusions: Exosomes derived from ADSCs can ameliorate oxidative damage in mouse lung tissue, decrease the level of reactive oxygen species, 8-OHdG expression, and permeability of PMVECs induced by macrophage supernatant.

Visible-light photoredox catalysis-enabled borocyclopropanation of alkenes

A convenient method for the synthesis of cyclopropyl boronates via visible-light photoredox-catalyzed borocyclopropanation of alkenes has been established. This protocol is characterized by its wide substrate scope and mild reaction conditions.

Genetic inhibition of RIPK3 ameliorates functional outcome in controlled cortical impact independent of necroptosis

Traumatic brain injury (TBI) is a leading cause of death and disability with no specific effective therapy, in part because disease driving mechanisms remain to be elucidated. Receptor interacting protein kinases (RIPKs) are serine/threonine kinases that assemble multi-molecular complexes that induce apoptosis, necroptosis, inflammasome and nuclear factor kappa B activation. Prior studies using pharmacological inhibitors implicated necroptosis in the pathogenesis of TBI and stroke, but these studies cannot be used to conclusively demonstrate a role for necroptosis because of the possibility of off target effects. Using a model of cerebral contusion and RIPK3 and mixed lineage kinase like knockout (MLKL^-/-) mice, we found evidence for activation of RIPK3 and MLKL and assembly of a RIPK1-RIPK3-MLKL necrosome complex in pericontusional brain tissue. Phosphorylated forms of RIPK3 and MLKL were detected in endothelium, CD11b + immune cells, and neurons, and RIPK3 was upregulated and activated in three-dimensional human endothelial cell cultures subjected to CCI. RIPK3^-/- and MLKL^-/- mice had reduced blood-brain barrier damage at 24 h (p < 0.05), but no differences in neuronal death (6 h, p = ns in CA1, CA3 and DG), brain edema (24 h, p = ns), or lesion size (4 weeks, p = ns) after CCI. RIPK3^-/-, but not MLKL^-/- mice, were protected against postinjury motor and cognitive deficits at 1-4 weeks (RIPK3^-/- vs WT: p < 0.05 for group in wire grip, Morris water maze hidden platform trials, p < 0.05 for novel object recognition test, p < 0.01 for rotarod test). RIPK3^-/- mice had reduced infiltrating leukocytes (p < 0.05 vs WT in CD11b + cells, microglia and macrophages), HMGB1 release and interleukin-1 beta activation at 24-48 h (p < 0.01) after CCI. Our data indicate that RIPK3 contributes to functional outcome after cerebral contusion by mechanisms involving inflammation but independent of necroptosis.

The efficacy and safety of Xuesaitong injection combined with western medicines in the treatment of ischemic stroke: an updated systematic review and meta-analysis

BACKGROUND

Due to constantly emerging new studies on Xuesaitong injection (XST) agent, it is necessary to summarize and analyze the latest published clinical research data to re-evaluate the clinical efficacy and safety of XST. This study mainly aimed to evaluate the clinical efficacy and safety of XST combined with western medicines (WM) for ischemic stroke treatment.

METHODS

The related databases were searched to collect all randomized controlled trials (RCTs) comparing the combination of XST and WM with WM alone for the treatment of patients with ischemic stroke. Participant, intervention, comparison, outcome and study type (PICOS) was the inclusion criteria of all studies. The search for and data extraction of the included studies was performed by 2 researchers, who then conducted quality evaluation. The Cochrane Collaboration's risk of bias tool was used for the article evaluation. The software RevMan 5.3 and Stata 15.0 were used for pooled analysis.

RESULTS

A total of 12 RCTs were included involving 1,769 patients with ischemic stroke, which combined XST with WM therapy. Moreover, the funnel plot showed that there was no obvious publication bias in the included studies. Meta-analysis showed that the total effective rate in the XST combined with WM group was higher than that in the WM alone group [odds ratio (OR) =4.04, 95% confidence interval (CI): 2.86 to 5.73, P<0.001]. The National Institutes of Health Stroke Scale (NIHSS) score in the XST combined with WM group was significantly lower than that in the WM alone group [weighted mean difference (WMD) =-3.17, 95% CI: -4.14 to -2.20, P<0.001]. In addition, XST combined with WM significantly reduced the plasma viscosity, fibrinogen level, whole blood high shear viscosity, and whole blood low shear viscosity in patients with ischemic stroke (P<0.01). For the comparison of adverse reactions, the results showed that the adverse reactions among patients with ischemic stroke in the XST combined with WM group and in the WM group did not differ significantly.

DISCUSSION

Compared with single WM medication, XST combined with WM improves the total clinical effective rate, promotes the recovery of patients' neurological function, and has few adverse reactions and high safety in clinical application.

Single-scatter path loss model of LED-based non-line-of-sight ultraviolet communications: publisher's note

This publisher's note contains corrections to Opt. Lett.46, 4013 (2021)OPLEDP0146-959210.1364/OL.435418.

[Expression and significance of TGF-β1, p38MAPK and BMP-7 protein in liver specimens of patients with alveolar hepatic echinococcosis]

OBJECTIVE

To detect the expression of transforming growth factor-β1 (TGF-β1), p38MAPK and bone morphogenetic protein-7 (BMP-7) protein in the liver specimens of patients with hepatic alveolar echinococcosis, and to investigate the potential role of TGF-β1, p38MAPK and BMP-7 protein in hepatic fibrosis caused by hepatic alveolar echinococcosis.

METHODS

A total of 20 patients with hepatic alveolar echinococcosis were enrolled as study subjects, and hepatic specimens were sampled from the sites within 0.5 cm (Group A) and 0.5 to 1.5 cm from hepatic alveolar echinococcosis lesions (Group B), while normal liver specimens sampled from the sites 2 cm and greater from hepatic alveolar echinococcosis lesions served as controls (Group C). The fibrosis of liver specimens was pathological examined using HE and Masson staining, and the expression of TGF-β1, p38MAPK and BMP-7 protein was quantified in liver tissues using Western blotting. The associations of TGF-β1, p38MAPK and BMP-7 protein expression with hepatic fibrosis were assessed.

RESULTS

HE staining showed the malaligned structure of hepatocytes and destruction of the structure of hepatic lobules at various degrees in liver specimens in groups A and B, with hepatocyte degeneration, atrophy and necrosis, hyperplasia of fibrous tissues and eosinophilic granulocyte infiltration seen, while no abnormal pathological alterations of liver tissues, normal hepatocyte structure and morphology and uniform size, no malaligned structure of hepatocytes, clear structure of hepatic lobules, no or mild hepatocyte degeneration or necrosis, and no eosinophilic granulocyte infiltration were seen in Group C. Masson staining showed that there was hyperplasia of multiple fibrous connective tissues in the liver portal areas in groups A and B, with fibrosis seen in hepatic lobules, while no obvious pathological changes were seen in Group C. There were significant differences seen in TGF-β1 (P < 0.001), p38MAPK (P < 0.01) and BMP-7 protein (P < 0.05) expression in liver tissues in groups A, B and C, and higher TGF-β1, p38MAPK and BMP-7 protein expression was quantified in groups A and B than in Group C (all P values < 0.05), while greater TGF-β1, p38MAPK and BMP-7 protein expression was detected in Group B than in Group C (all P values < 0.05). The expression of TGF-β1, p38MAPK and BMP-7 protein correlated positively with the severity of hepatic fibrosis (r = 0.866, 0.702 and 0.801, all P values < 0.05), and there were significant differences in TGF-β1 (F = 72.580, P < 0.01), p38MAPK (χ² = 31.705, P < 0.01) and BMP-7 protein expression (χ² = 48.388, P < 0.01) among liver tissues with different degrees of fibrosis. The TGF-β1 protein expression correlated positively with p38MAPK and BMP-7 protein expression (r = 0.607 and 0.702, both P values < 0.001), and the BMP-7 protein expression also correlated positively with p38MAPK protein expression (r = 0.456, P < 0.001).

CONCLUSIONS

The interaction among TGF-β1, p38MAPK and BMP-7 jointly participates in the development of hepatic fibrosis induced hepatic alveolar echinococcosis.

Single-scatter path loss model of LED-based non-line-of-sight ultraviolet communications

Light-emitting diodes (LEDs) are popularly used as light sources in non-line-of-sight (NLOS) ultraviolet communications (UVC). However, currently reported single-scatter path loss (PL) models of NLOS UVC links assume that the radiant intensity of the light source is uniformly distributed within the beam divergence angle, which cannot well characterize the light emission pattern of LEDs. In this Letter, we propose a single-scatter PL model for LED-based NLOS UVC systems, and the corresponding analytical expression is derived by modeling the LED emission pattern as a Lambertian distribution. Monte Carlo simulations and experimental results are provided to verify the effectiveness of the proposed PL model. Results show that the proposed model can accurately predict PL results in actual situations. The root-mean-square error of the proposed PL model is only about 1 dB in typical scenarios with experimental results as benchmarks. Also, the proposed model is much easier to implement than the currently reported PL model with the light source model of a uniformly distributed emission pattern.

Lenticulostriate artery combined with neuroimaging markers of cerebral small vessel disease differentiate the pathogenesis of recent subcortical infarction

Recent subcortical infarction (RSI) in the lenticulostriate artery (LSA) territory with a non-stenotic middle cerebral artery is a heterogeneous entity. We aimed to investigate the role of LSA combined with neuroimaging markers of cerebral small vessel disease (CSVD) in differentiating the pathogenic subtypes of RSI by whole-brain vessel-wall magnetic resonance imaging (WB-VWI). Fifty-two RSI patients without relevant middle cerebral artery (MCA) stenosis on magnetic resonance angiography were prospectively enrolled. RSI was dichotomized as branch atheromatous disease (BAD; a culprit plaque located adjacent to the LSA origin) (n = 34) and CSVD-related lacunar infarction (CSVD-related LI; without plaque or plaque located distal to the LSA origin) (n = 18). Logistic regression analysis showed lacunes (odds ratio [OR] 9.68, 95% confidence interval [CI] 1.71-54.72; P = 0.010) and smaller number of LSA branches (OR 0.59, 95% CI 0.36-0.96; P = 0.034) were associated with of BAD, whereas severe deep white matter hyperintensities (DWMH) (OR 0.11, 95% CI 0.02-0.71; P = 0.021) was associated with CSVD-related LI. In conclusion, the LSA branches combined with lacunes and severe DWMH may delineate subtypes of SSI. The WB-VWI technique could be a credible tool for delineating the heterogeneous entity of SSI in the LSA territory.

Long non-coding RNA XIST confers aggressive progression via miR-361-3p/STX17 in retinoblastoma cells

OBJECTIVE

Retinoblastoma (RB) is a frequent intraocular tumor in children. Long-non-coding RNA X inactive specific transcript (XIST) has been reported to participate in the RB process, while its potential role remains largely unknown.

PATIENTS AND METHODS

The expression patterns of XIST, microRNA (miR)-361-3p, and Syntaxin 17 (STX17) were determined using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), flow cytometry, and transwell assays were employed to reckon cell viability, apoptosis, and mobility in RB cells, respectively. Besides, the levels of STX17 and autophagy-related proteins were detected utilizing Western blot. Dual-Luciferase reporter assay was implemented to evaluate the interaction between miR-361-3p and XIST or STX17, and the role of XIST in tumor growth was analyzed through xenograft tumor model.

RESULTS

The expression levels of XIST and STX17 were higher in RB tissues and cells, but miR-361-3p was downregulated. Loss of XIST was inversely connected with aggressive characteristics, showing as the curb of cell proliferation, migration, invasion, autophagy, and enhancement of apoptosis in RB cells. Also, the deficiency of XIST caused the decrease of tumor growth in vivo. Meanwhile, miR-361-3p inhibitor partially rescued XIST detection-mediated cell behaviors in vitro. Similarly, miR-361-3p mimic-mediated suppressive effect on aggressive phenotypes was abolished after overexpression of STX17 in RB cells. Mechanically, XIST was a sponge of miR-361-3p to regulate STX17.

CONCLUSIONS

XIST functioned as an oncogenic lncRNA via miR-361-3p/STX17 axis in the progression of RB, which might provide a promising theoretical basis for the clinical therapy of RB.

Longitudinal Flow Decorrelations in Xe+Xe Collisions at sqrt[s_{NN}]=5.44 TeV with the ATLAS Detector

The first measurement of longitudinal decorrelations of harmonic flow amplitudes v_{n} for n=2-4 in Xe+Xe collisions at sqrt[s_{NN}]=5.44  TeV is obtained using 3  μb^{-1} of data with the ATLAS detector at the LHC. The decorrelation signal for v_{3} and v_{4} is found to be nearly independent of collision centrality and transverse momentum (p_{T}) requirements on final-state particles, but for v_{2} a strong centrality and p_{T} dependence is seen. When compared with the results from Pb+Pb collisions at sqrt[s_{NN}]=5.02  TeV, the longitudinal decorrelation signal in midcentral Xe+Xe collisions is found to be larger for v_{2}, but smaller for v_{3}. Current hydrodynamic models reproduce the ratios of the v_{n} measured in Xe+Xe collisions to those in Pb+Pb collisions but fail to describe the magnitudes and trends of the ratios of longitudinal flow decorrelations between Xe+Xe and Pb+Pb. The results on the system-size dependence provide new insights and an important lever arm to separate effects of the longitudinal structure of the initial state from other early and late time effects in heavy-ion collisions.

Search for Dark Matter Produced in Association with a Dark Higgs Boson Decaying into W^{±}W^{∓} or ZZ in Fully Hadronic Final States from sqrt[s]=13 TeV pp Collisions Recorded with the ATLAS Detector

Several extensions of the Standard Model predict the production of dark matter particles at the LHC. An uncharted signature of dark matter particles produced in association with VV=W^{±}W^{∓} or ZZ pairs from a decay of a dark Higgs boson s is searched for using 139  fb^{-1} of pp collisions recorded by the ATLAS detector at a center-of-mass energy of 13 TeV. The s→V(qq[over ¯])V(qq[over ¯]) decays are reconstructed with a novel technique aimed at resolving the dense topology from boosted VV pairs using jets in the calorimeter and tracking information. Dark Higgs scenarios with m_{s}>160  GeV are excluded.

Pulsed electromagnetic fields synergize with graphene to enhance dental pulp stem cell-derived neurogenesis by selectively targeting TRPC1 channels

Conventional root canal treatment replaces the infected pulp with defined materials. Alternative cell-based tissue engineering strategies aim to regenerate a fully functional pulp within the root canal. Despite recent advances in this area, however, the regeneration of an innervated pulp remains a major challenge in the field. Both graphene (2DG) and pulsed electromagnetic fields (PEMFs) independently have been shown to promote diverse cellular developmental programs. The present study showed that 2DG promoted the neurogenic induction of human dental pulp stem cells (hDPSCs) by upregulating and accelerating the expression of mature neuronal markers. Notably, 2DG induced the highest expression of transient receptor potential canonical cation channel type 1 (TRPC1) during early neurogenesis. As brief PEMF exposure promotes in vitro differentiation by activating a TRPC1-mitochondrial axis, an opportunity to combine 2DG with developmentally targeted PEMF exposure for synergistic effects was realizable. Neurogenic gene expression, neurotransmitter release, and reactive oxygen species (ROS) production were greatly enhanced by a brief (10 min) and low amplitude (2 mT) PEMF exposure timed to coincide with the highest TRPC1 expression from hDPSCs on 2DG. In contrast, hDPSCs on glass were less responsive to PEMF exposure. The capacity of PEMFs to promote neurogenesis was precluded by the administration of penicillin/streptomycin, mirroring previous studies demonstrating that aminoglycoside antibiotics block TRPC1-mediated calcium entry and verifying the contribution of TRPC1 in this form of magnetoreception. Hence, graphene created a more conducive environment for subsequent PEMF-stimulated neurogenic induction of hDPSCs through their mutual capacity to activate TRPC1with subsequent ROS production.

Medium-Induced Modification of Z-Tagged Charged Particle Yields in Pb+Pb Collisions at 5.02 TeV with the ATLAS Detector

The yield of charged particles opposite to a Z boson with large transverse momentum (p_{T}) is measured in 260  pb^{-1} of pp and 1.7  nb^{-1} of Pb+Pb collision data at 5.02 TeV per nucleon pair recorded with the ATLAS detector at the Large Hadron Collider. The Z boson tag is used to select hard-scattered partons with specific kinematics, and to observe how their showers are modified as they propagate through the quark-gluon plasma created in Pb+Pb collisions. Compared with pp collisions, charged-particle yields in Pb+Pb collisions show significant modifications as a function of charged-particle p_{T} in a way that depends on event centrality and Z boson p_{T}. The data are compared with a variety of theoretical calculations and provide new information about the medium-induced energy loss of partons in a p_{T} regime difficult to measure through other channels.

Nickel-catalyzed defluorinative alkylation of C(sp2)–F bonds

A nickel-catalyzed defluorinative alkylation of unactivated C(sp²)–F electrophiles using commercially available trialkylaluminum reagents, thus forming the C(sp²)–C(sp³) bonds is reported.

Observation and Measurement of Forward Proton Scattering in Association with Lepton Pairs Produced via the Photon Fusion Mechanism at ATLAS

The observation of forward proton scattering in association with lepton pairs (e^{+}e^{-}+p or μ^{+}μ^{-}+p) produced via photon fusion is presented. The scattered proton is detected by the ATLAS Forward Proton spectrometer, while the leptons are reconstructed by the central ATLAS detector. Proton-proton collision data recorded in 2017 at a center-of-mass energy of sqrt[s]=13  TeV are analyzed, corresponding to an integrated luminosity of 14.6  fb^{-1}. A total of 57 (123) candidates in the ee+p (μμ+p) final state are selected, allowing the background-only hypothesis to be rejected with a significance exceeding 5 standard deviations in each channel. Proton-tagging techniques are introduced for cross-section measurements in the fiducial detector acceptance, corresponding to σ_{ee+p}=11.0±2.6(stat)±1.2(syst)±0.3(lumi) and σ_{μμ+p}=7.2±1.6(stat)±0.9(syst)±0.2(lumi)  fb in the dielectron and dimuon channel, respectively.

Search for Heavy Resonances Decaying into a Photon and a Hadronically Decaying Higgs Boson in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter presents a search for the production of new heavy resonances decaying into a Higgs boson and a photon using proton-proton collision data at sqrt[s]=13  TeV collected by the ATLAS detector at the LHC. The data correspond to an integrated luminosity of 139  fb^{-1}. The analysis is performed by reconstructing hadronically decaying Higgs boson (H→bb[over ¯]) candidates as single large-radius jets. A novel algorithm using information about the jet constituents in the center-of-mass frame of the jet is implemented to identify the two b quarks in the single jet. No significant excess of events is observed above the expected background. Upper limits are set on the production cross-section times branching fraction for narrow spin-1 resonances decaying into a Higgs boson and a photon in the resonance mass range from 0.7 to 4 TeV, cross-section times branching fractions are excluded between 11.6 fb and 0.11 fb at a 95% confidence level.

Search for Higgs Boson Decays into a Z Boson and a Light Hadronically Decaying Resonance Using 13 TeV pp Collision Data from the ATLAS Detector

A search for Higgs boson decays into a Z boson and a light resonance in two-lepton plus jet events is performed, using a pp collision dataset with an integrated luminosity of 139  fb^{-1} collected at sqrt[s]=13  TeV by the ATLAS experiment at the CERN LHC. The resonance considered is a light boson with a mass below 4 GeV from a possible extended scalar sector or a charmonium state. Multivariate discriminants are used for the event selection and for evaluating the mass of the light resonance. No excess of events above the expected background is found. Observed (expected) 95% confidence-level upper limits are set on the Higgs boson production cross section times branching fraction to a Z boson and the signal resonance, with values in the range 17-340 pb (16_{-5}^{+6}-320_{-90}^{+130}  pb) for the different light spin-0 boson mass and branching fraction hypotheses, and with values of 110 and 100 pb (100_{-30}^{+40} and 100_{-30}^{+40}  pb) for the η_{c} and J/ψ hypotheses, respectively.

Dijet Resonance Search with Weak Supervision Using sqrt[s]=13 TeV pp Collisions in the ATLAS Detector

This Letter describes a search for narrowly resonant new physics using a machine-learning anomaly detection procedure that does not rely on signal simulations for developing the analysis selection. Weakly supervised learning is used to train classifiers directly on data to enhance potential signals. The targeted topology is dijet events and the features used for machine learning are the masses of the two jets. The resulting analysis is essentially a three-dimensional search A→BC, for m_{A}∼O(TeV), m_{B},m_{C}∼O(100  GeV) and B, C are reconstructed as large-radius jets, without paying a penalty associated with a large trials factor in the scan of the masses of the two jets. The full run 2 sqrt[s]=13  TeV pp collision dataset of 139  fb^{-1} recorded by the ATLAS detector at the Large Hadron Collider is used for the search. There is no significant evidence of a localized excess in the dijet invariant mass spectrum between 1.8 and 8.2 TeV. Cross-section limits for narrow-width A, B, and C particles vary with m_{A}, m_{B}, and m_{C}. For example, when m_{A}=3  TeV and m_{B}≳200  GeV, a production cross section between 1 and 5 fb is excluded at 95% confidence level, depending on m_{C}. For certain masses, these limits are up to 10 times more sensitive than those obtained by the inclusive dijet search. These results are complementary to the dedicated searches for the case that B and C are standard model bosons.

[Debridement combined with negative-pressure wound therapy and local flap for treating a case of stingray sting]

On January 10, 2018, a 35-year-old male patient with a 3 day stingray stinger injury in his left thigh was admitted to Xuzhou Central Hospital. At the time of admission, the patient's left thigh was red, swollen, and painful. On the day of admission, the patient underwent emergency operation in the outpatient operating room for local debridement to remove the infected and necrotic tissue. After the routine dressing change and the wound got better, surgical debridement and negative-pressure wound therapy were performed, and finally local flap was used to repair the wound. On the 14th day after the flap repair operation, the suture was removed and the patient was discharged. After half a year follow-up, the appearance of the operation area recovered well. This case suggests that the timely and correct pre-hospital treatment, thorough and timely debridement, and systemic antibiotic application are important means to reduce further injury of toxin. The local flap can achieve satisfactory result on wound healing after the wound bed is prepared by negative-pressure wound therapy.

CP Properties of Higgs Boson Interactions with Top Quarks in the tt[over ¯]H and tH Processes Using H→γγ with the ATLAS Detector

A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H→γγ), and their production in association with a top quark pair (tt[over ¯]H) or single top quark (tH) is studied. The analysis uses 139  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of sqrt[s]=13  TeV with the ATLAS detector at the Large Hadron Collider. Assuming a CP-even coupling, the tt[over ¯]H process is observed with a significance of 5.2 standard deviations. The measured cross section times H→γγ branching ratio is 1.64_{-0.36}^{+0.38}(stat)_{-0.14}^{+0.17}(sys)  fb, and the measured rate for tt[over ¯]H is 1.43_{-0.31}^{+0.33}(stat)_{-0.15}^{+0.21}(sys) times the Standard Model expectation. The tH production process is not observed and an upper limit on its rate of 12 times the Standard Model expectation is set. A CP-mixing angle greater (less) than 43 (-43)° is excluded at 95% confidence level.

Search for Heavy Higgs Bosons Decaying into Two Tau Leptons with the ATLAS Detector Using pp Collisions at sqrt[s]=13 TeV

A search for heavy neutral Higgs bosons is performed using the LHC Run 2 data, corresponding to an integrated luminosity of 139  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV recorded with the ATLAS detector. The search for heavy resonances is performed over the mass range 0.2-2.5 TeV for the τ^{+}τ^{-} decay with at least one τ-lepton decaying into final states with hadrons. The data are in good agreement with the background prediction of the standard model. In the M_{h}^{125} scenario of the minimal supersymmetric standard model, values of tanβ>8 and tanβ>21 are excluded at the 95% confidence level for neutral Higgs boson masses of 1.0 and 1.5 TeV, respectively, where tanβ is the ratio of the vacuum expectation values of the two Higgs doublets.

Machine Learning Algorithm Helps Identify Non-Diagnosed Prodromal Alzheimer's Disease Patients in the General Population

BACKGROUND

Recruiting patients for clinical trials of potential therapies for Alzheimer's disease (AD) remains a major challenge, with demand for trial participants at an all-time high. The AD treatment R and D pipeline includes around 112 agents. In the United States alone, 150 clinical trials are seeking 70,000 participants. Most people with early cognitive impairment consult primary care providers, who may lack time, diagnostic skills and awareness of local clinical trials. Machine learning and predictive analytics offer promise to boost enrollment by predicting which patients have prodromal AD, and which will go on to develop AD.

OBJECTIVES

The authors set out to develop a machine learning predictive model that identifies prodromal AD patients in the general population, to aid early AD detection by primary care physicians and timely referral to expert sites for biomarker confirmation of diagnosis and clinical trial enrollment.

DESIGN

The authors use a classification machine learning algorithm to extract patterns within healthcare claims and prescription data three years prior to AD diagnosis/AD drug initiation.

SETTING

The study focused on subjects included within proprietary IQVIA US data assets (claims and prescription databases). Patient information was extracted from January 2010 to July 2018, for cohorts aged between 50 and 85 years.

PARTICIPANTS

A total of 88,298,289 subjects aged between 50 and 85 years were identified. For the positive cohort, 667,288 subjects were identified who had 24 months of medical history and at least one record with AD or AD treatment. For the negative cohort, 3,670,254 patients were selected who had a similar length of medical history and who were matched to positive cohort subjects based on the prevalence rate. The scoring cohort was selected based on availability of recent medical data of 2-5 years and included 72,670,283 subjects between the ages of 50 and 85 years. Intervention (if any): None.

MEASUREMENTS

A list of clinically-relevant and interpretable predictors was generated and extracted from the data sets for each subject, including pharmacological treatments (NDC/product), office/specialist visits (specialty), tests and procedures (HCPCS and CPT), and diagnosis (ICD). The positive cohort was defined as patients who have AD diagnosis/AD treatment with a 3 years offset as an estimate for prodromal AD diagnosis. Supervised ML techniques were used to develop algorithms to predict the occurrence of prodromal AD cases. The sample dataset was divided randomly into a training dataset and a test dataset. The classification models were trained and executed in the PySpark framework. Training and evaluation of LogisticRegression, DecisionTreeClassifier, RandomForestClassifier, and GBTClassifier were executed using PySpark's mllib module. The area under the precision-recall curve (AUCPR) was used to compare the results of the various models.

RESULTS

The AUCPRs are 0.426, 0.157, 0.436, and 0.440 for LogisticRegression, DecisionTreeClassifier, RandomForestClassifier, and GBTClassifier, respectively, meaning that GBTClassifier (Gradient Boosted Tree) outperforms the other three classifiers. The GBT model identified 222,721 subjects in the prodromal AD stage with 80% precision. Some 76% of identified prodromal AD patients were in the primary care setting.

CONCLUSIONS

Applying the developed predictive model to 72,670,283 U.S. residents, 222,721 prodromal AD patients were identified, the majority of whom were in the primary care setting. This could drive major advances in AD research by enabling more accurate and earlier prodromal AD diagnosis at the primary care physician level , which would facilitate timely referral to expert sites for in-depth assessment and potential enrolment in clinical trials.

Measurement of the Lund Jet Plane Using Charged Particles in 13 TeV Proton-Proton Collisions with the ATLAS Detector

The prevalence of hadronic jets at the LHC requires that a deep understanding of jet formation and structure is achieved in order to reach the highest levels of experimental and theoretical precision. There have been many measurements of jet substructure at the LHC and previous colliders, but the targeted observables mix physical effects from various origins. Based on a recent proposal to factorize physical effects, this Letter presents a double-differential cross-section measurement of the Lund jet plane using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data collected with the ATLAS detector using jets with transverse momentum above 675 GeV. The measurement uses charged particles to achieve a fine angular resolution and is corrected for acceptance and detector effects. Several parton shower Monte Carlo models are compared with the data. No single model is found to be in agreement with the measured data across the entire plane.

Application of a modified electrocardiogram-guided technique for umbilical venous catheterisation in neonates: A retrospective trial

AIM

To investigate the effectiveness and safety of modified electrocardiogram (ECG)-guided technique in umbilical venous catheterisation in neonates.

METHODS

Sixty-six critically ill neonates underwent umbilical venous catheterisation with (ECG group) or without (control group) ECG guidance from January 2017 to March 2019. We retrospectively analysed and compared the rate of correct tip placement on first try, unplanned extubation rate and incidence of catheter-related complications between the two groups.

RESULTS

There were 33 patients in each group. The ECG group showed significantly higher rate of correct tip placement on first try (P < 0.001), lower unplanned extubation rate (P < 0.001), but identical incidence of catheter-related complications (P = 0.492) comparing with the control group.

CONCLUSION

The ECG-guided technique is an effective and safe method for umbilical venous catheterisation. The connecting method we modified made this technique more practical and can be promoted to areas without access to specific ECG adaptors.

Measurement of Azimuthal Anisotropy of Muons from Charm and Bottom Hadrons in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

The elliptic flow of muons from the decay of charm and bottom hadrons is measured in pp collisions at sqrt[s]=13  TeV using a data sample with an integrated luminosity of 150  pb^{-1} recorded by the ATLAS detector at the LHC. The muons from heavy-flavor decay are separated from light-hadron decay muons using momentum imbalance between the tracking and muon spectrometers. The heavy-flavor decay muons are further separated into those from charm decay and those from bottom decay using the distance-of-closest-approach to the collision vertex. The measurement is performed for muons in the transverse momentum range 4-7 GeV and pseudorapidity range |η|<2.4. A significant nonzero elliptic anisotropy coefficient v_{2} is observed for muons from charm decays, while the v_{2} value for muons from bottom decays is consistent with zero within uncertainties.

Mirror movements induced by hemiballism due to putamen infarction: a case report and literature review

Mirror movements (MMs), which are involuntary movements of one limb that synchronously mirror voluntary movements of the contralateral limb, are a relatively uncommon complication of strokes. Here we report what appears to be the first case of putamen infarction manifesting as MMs in one side of the body induced by contralateral hemiballism. MMs and hemiballism were nearly entirely eliminated after one week of clonazepam and haloperidol therapy. During the subsequent one year of standard ischemic stroke prevention measures, no further episodes of involuntary movement occurred. Our case and literature review highlight that acute stroke can manifest as hemiballism and MMs, which should be recognized as soon as possible to ensure timely management.

Search for Magnetic Monopoles and Stable High-Electric-Charge Objects in 13 Tev Proton-Proton Collisions with the ATLAS Detector

A search for magnetic monopoles and high-electric-charge objects is presented using 34.4  fb^{-1} of 13 TeV pp collision data collected by the ATLAS detector at the LHC during 2015 and 2016. The considered signature is based upon high ionization in the transition radiation tracker of the inner detector associated with a pencil-shape energy deposit in the electromagnetic calorimeter. The data were collected by a dedicated trigger based on the tracker high-threshold hit capability. The results are interpreted in models of Drell-Yan pair production of stable particles with two spin hypotheses (0 and 1/2) and masses ranging from 200 to 4000 GeV. The search improves by approximately a factor of 5 the constraints on the direct production of magnetic monopoles carrying one or two Dirac magnetic charges and stable objects with electric charge in the range 20≤|z|≤60 and extends the charge range to 60<|z|≤100.