Immunosensor-based rapid quantitative detection of Newcastle disease virus antibodies using innovative gold immunochromatographic assay

AIMS

A novel quantitative method for rapid Newcastle disease virus (NDV) antibody detection was developed based on an innovative gold immunochromatographic assay with a quantitative immunosensor.

METHODS AND RESULTS

NDV antibody-detecting test strips containing a two-reaction system and double-test lines (T1, T2) were prepared. The test results were judged according to the signal ratio between the test and control lines as measured by the quantitative immunosensor. The minimum detection limit of the test strips for NDV antibodies was 2² titres. In addition, the assay was highly specific because only NDV antibodies produced visible test lines on the strip. The clinical application of the strips was tested by detecting NDV antibodies in 506 serum samples collected from chickens. The results showed a coincidence of 92·49% with those of the haemagglutination inhibition assay.

CONCLUSIONS

The strips were successfully prepared and showed high specificity towards NDV, sensitivity and stability.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study describes a new method for detection of NDV antibody and provides a reference basis for rapid and quantitative monitoring of NDV antibodies. This new method overcomes the limitation of the existing colloidal gold immunochromatography, which only produces qualitative or semi-quantitative results.

Function of IL-33 in Wound Age Estimation of Skin Wounds in Mice

Abstract

Objective To explore the application value of interleukin-33 （IL-33） in wound age estimation in forensic practice by observing the sequential changes of IL-33 after skin wound. Methods Skin wound models were generated on the back of mice with a round file of 5 mm in diameter. Skin samples of the same size were taken from the same parts of mice in control group and injury group 1 h, 3 h, 6 h, 12 h, 1 d, 3 d, 5 d, 7 d and 10 d after skin wound. Hematoxylin-eosin （HE） staining method was applied to observe the morphological changes in the recovering process after skin wound. Western blotting, immunohistochemistry staining and double immunofluorescence staining methods were applied to detect the expression changes of IL-33 in the skin wound samples. Results The results of Western blotting showed that the expression of IL-33 protein decreased slightly at 3 h after skin wound, increased gradually at 6 h after skin wound, and reached the peak value at 3 d, then decreased gradually. Immunohistochemistry staining results showed that faint positive expression of IL-33 was observed in epidermis, hair follicles, sebaceous glands and dermal resident cells of the control group skin. The positive cell rate of IL-33 increased at 3 h after skin wound and reached the peak value at 3 d, then decreased gradually. The results of double immunofluorescence staining showed that the majority of IL-33 positive cells from 1 d to 3 d after wound were macrophages, while the majority of IL-33 positive cells from 5 d to 7 d after wound were myofibroblasts. In addition, the results of HE staining showed that the wound healing process of the skin wound model was consistent with the pathological development law of inflammation. Conclusion IL-33 could become a reference index for wound age estimation of skin wound in forensic practice.

[Short-term efficacy of robotic-assisted total mesorectal excision with and without lateral lymph node dissection for mid-low advanced rectal cancer: a propensity score matching analysis]

Objective: To evaluate the feasibility, safety and efficacy of robotic-assisted lateral lymph node dissection for mid-low advanced rectal cancer. Methods: A retrospective cohort study was performed. Inclusion criteria: (1) age between 18 and 80 years old; (2) rectal adenocarcinoma diagnosed by pathology; (3) without distant metastasis by preoperative CT or MRI; (4) patients underwent robotic-assisted total mesorectal resection (TME). Exclusion criteria: (1) conversion to open surgery; (2) multiple primary tumors; (3) patients underwent combined multiple organ resection. According to the above criteria, 137 patients undergoing robotic-assisted mid-low rectal cancer resection in the First Affiliated Hospital of Xi'an Jiaotong University from December 2016 to April 2019 were enrolled. Ninety-seven cases underwent robotic-assisted total mesorectal excision (TME group) and 40 underwent robotic-assisted total mesorectal resection with lateral lymph node dissection (LLND) (TME+LLND group, pelvic LLND was performed with neurovascular guidance to retain pelvic autonomic nerves in the order of the left side the first and then the right side). The propensity score matching of 1:1 was performed with R software, based on age, sex, BMI, ASA classification, distance from tumor to the anal verge, preoperative chemoradiotherapy history, preoperative abdominal surgery history, the size of tumors and TNM stage. The operative indicators, postoperative recovery, pathology and postoperative complications within 30 days were compared between the two groups. Results: A total of 72 cases were successfully matched (36 in each group), and there were no statistically significant differences in baseline data between the two groups (all P>0.05). The operation time of TME+LLND group was significantly longer than that of TME group [275.0 (180-405) minutes vs. 220.0 (140-320) minutes, Z=-3.680, P<0.001], while there were no statistically significant differences in blood loss during operation, time to postoperative first flatus, postoperative hospital stay, total hospital cost, tumor differentiation, and distal resection length of margin (all P>0.05). Circumferential resection margin was all negative in both groups. The number of harvested lymph modes in the TME+LLND groups was higher than that in the TME group [26 (18-37) vs. 14 (9-36), Z=-6.407, P<0.001]. In addition, there were no statistically significant differences in postoperative morbidity and Clavien-Dindo classification of complication within 30 days between the two groups (both P>0.05). Conclusions: Although robotic lateral lymph node dissection requires longer operation time, it is a feasible, safe and effective procedure.

Application of Virtual Anatomy Technology in Postmortem Examination of Medical Dispute Cases

Abstract

Objective To discuss the application value of CT scanning technology in cause of death determination of medical dispute cases. Methods From July 2017 to December 2018, postmortem CT imaging data of 12 medical dispute cases were collected. CT imaging diagnosis results and anatomy findings as well as differences between antemortem and postmortem CT diagnosis were compared. The advantages and disadvantages of CT routine tests of the cadavers in terms of the diagnosis of disease and damage were analyzed. Results The comparison between CT imaging diagnosis and anatomical findings showed that CT scans had advantages in the diagnosis of disease and damage with large differences in density changes, such as atelectasis, pneumonia, calcification, fracture and hemorrhage, etc. The comparison of CT diagnosis in antemortem and postmortem examination showed that the cadavers of medical dispute cases were well preserved and that postmortem CT scan was meaningful for the diagnosis of antemortem diseases. Conclusion Virtual anatomy technology has a relatively high application value in postmortem examination of medical dispute cases. It can provide effective information for the appraisers before the autopsy and can also provide a reference for cause of death analysis when the anatomy cannot be performed.

Association of daytime napping with incident stroke in middle-aged and older adults: a large community-based study

BACKGROUND AND PURPOSE

There are conflicting reports on the association between daytime napping and incident stroke. This study was designed to investigate the relationship between daytime napping and stroke within a community-based cohort.

METHODS

The present prospective study was based on the Sleep Heart Health Study. Napping habits were assessed with a self-reported Sleep Habits Questionnaire. Participants with napping habits of different durations and frequencies were followed up until the first stroke occurred or the final censoring date. Cox proportional hazards models were used to estimate the relationship between napping habits and stroke.

RESULTS

A total of 4757 participants (2219 men, mean age 63.6 ± 11.1 years) were enrolled in this study. Compared with those taking no naps, multivariate proportional hazards models analysis indicated that individuals taking naps with a duration of >60 min [hazard ratio (HR), 2.460; 95% confidence interval (CI), 1.538-3.934] had a higher risk of stroke. There was also an increased risk of stroke among participants taking naps daily (HR, 1.563; 95% CI, 1.059-2.307) or five to six times/week (HR, 1.548; 95% CI, 1.026-2.335). After combining napping durations and frequencies, regular long naps (HR, 1.903; 95% CI, 1.182-3.065) and regular short naps (HR, 1.451; 95% CI, 1.010-2.084) were independent risk factors for incident stroke.

CONCLUSION

Daytime napping with a long duration (>30 min) or a high frequency (≥5 times/week) may increase the risk of stroke.

Association between Skeletal Muscle Strength and Dysphagia among Chinese Community-Dwelling Elderly Adults

OBJECTIVES

Swallowing disorder is a health burden for the elderly in China. This study aimed to investigate the prevalence of dysphagia and to test the association between skeletal muscle strength and swallowing problems among community-dwelling older adults.

DESIGN

A cross-sectional study.

SETTING

Community-dwelling Chinese elderly in China.

PARTICIPANTS

3361 adults aged 65 years or above were involved, among which 1740 (51.8%) were female, with average age of 72.64 (Standard deviation, SD=6.10) years old.

MEASUREMENTS

Handgrip strength (HGS) was used to evaluate skeletal muscle strength. Dysphagia assessment was performed using the Eating Assessment Tool-10 (EAT-10) and the 30mL water swallow test (WST). Binary logistic regression was used to evaluate the relationship between skeletal muscle strength and dysphagia, and covariates as age, gender, material status, etc. were adjusted.

RESULTS

The prevalence of dysphagia were 5.5% and 12.9%, screened by EAT-10 and 30mL WST respectively. Participants with dysphagia showed lower HGS (21.73 ± 9.20 vs. 25.66 ± 11.32, p<0.001, by EAT-10; 20.26 ± 9.88 vs. 26.22 ± 11.28, p<0.001, by WST). The adjusted model suggested that muscle strength is a protective factor for swallowing disorders (adjusted OR=0.974, 95%CI: 0.950-0.999, by EAT-10; adjusted OR=0.952, 95%CI: 0.933-0.972, by WST). Subgroup analyses of WST found the effects were significant among participants aged in 70-74 years group and ≥75 years group, rather than those aged under 70.

CONCLUSION

Dysphagia was significantly associated with skeletal muscle strength among the community-dwelling elderly population. Effective interventions should be taken to manage the decline of muscle strength for the older adults, especially early prevention before 70 years old.

Optimization extraction and characterization of Artemisia ordosica polysaccharide and its beneficial effects on antioxidant function and gut microbiota in rats

In this study, a novel polysaccharide was isolated from Artemisia ordosica by water-extraction-ethanol-precipitation method. The optimal extraction conditions of Artemisia ordosica polysaccharide (AOP) were determined by single factor investigation and response surface methodology optimization, and were shown as follows: a liquid–solid ratio of 15.4 : 1 mL g⁻¹, extraction time of 4.3 h, extraction temperature of 60 °C. Under the optimal conditions, the extraction yield and the sugar content of the AOP were 5.56% and 52.65%. Gel permeation chromatography coupled to multi-angle laser light scattering, a refractive index detection system and ion-exchange chromatography were used to determine the characterization of AOP. These results indicated that AOP, with a molecular weight of 2.1 kDa (62.6%) and 1.5 kDa (37.4%), had narrow polydispersity and rod conformations, and was composed of arabinose, galactose, glucose, xylose, mannose, galacturonic acid and glucuronic acid with molar ratio of 6.87 : 10.67 : 54.13 : 2.49 : 18.37 : 4.83 : 2.64 : 2.64. In addition, AOP exerted antioxidant ability in vitro and in vivo (rats). Moreover, AOP significantly modulated the composition of cecal microbiota population. Therefore, AOP is expected to be a functional ingredient for health improvement through improving antioxidant ability and modulating gut health.

Artemisia ordosica polysaccharide is expected to be functional ingredient for health improvement through improving antioxidant ability and modulating gut health.

The involvement of p38MAPK in the rat model of lower-extremity arterial ischemia-reperfusion injury

OBJECTIVE

This study aims to investigate the regulatory role of p38 mitogen-activated protein kinase (p38MAPK) in rats with lower-extremity arterial ischemia-reperfusion injury.

MATERIALS AND METHODS

A total of 60 Sprague-Dawley (SD) rats were randomly divided into four groups: control group (Group A), lower-extremity arterial ischemia-reperfusion group (Group B), lower-extremity arterial ischemic postconditioning group (Group C), and lower-extremity arterial ischemic postconditioning + SB203580 group (Group D, 5 μmol/L SB203580, the inhibitor of MAPK pathway, was injected after lower-extremity arterial ischemic postconditioning). The lower-extremity arterial vessels were collected after 24 h. The apoptosis in the lower-extremity arterial vessel in each group was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method. The expression of phosphorylated (p)-p38MAPK was measured via Western blotting, and the level of p-activating transcription factor-2 (ATF-2) was detected via immunohistochemical method.

RESULTS

The positive rate of apoptotic cells (%) in Group B was significantly increased compared to that in Group A (p<0.05). However, the positive rate was statistically decreased by postcondition in Group C, the rate was further reduced after injection of SB203580 in Group D compared to Group B (p<0.05). Compared with that in Group C, the expressions of p-p38MAPK and p-ATF-2 in Group D were significantly downregulated after injection of SB203580 (p<0.05).

CONCLUSIONS

Lower-extremity arterial ischemia-reperfusion postconditioning can significantly reduce the apoptosis level in vascular tissues, decrease the expressions of p-p38MAPK and downstream factor ATF-2, and alleviate the damage in lower-extremity arterial vessels. The inhibition of MAPK pathway further restricted the apoptosis and contributed to a promoting role in the recovery of lower-extremity arterial ischemia-reperfusion injury.

Expression changes of inflammatory cytokines TNF-α, IL-1β and HO-1 in hematoma surrounding brain areas after intracerebral hemorrhage

To study the expression changes of inflammatory factors heme oxygenase-1 (HO-1), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) in intracerebral hemorrhage (ICH), brain tissues surrounding hematoma were collected from ICH patients. The expressions of HO-1, TNF-α, IL- 1β, and other genes were examined at different time points of ICH. Changes in HO-1, TNF-α, and IL-1β positive cell numbers after ICH were detected by immunohistochemical staining. The results showed that the expressions of HO-1, TNF-α, and IL-1β had no significant changes in brain tissues surrounding hematoma within 6 hours after ICH (P > 0.05). Their expressions during 6-24 hours and 24-72 hours after ICH increased constantly. After reaching the peak, they remained steady or slightly decreased after 72 hours. The dynamic expression changes of HO-1, TNF-α, and IL-1β were observed and their development trends were interfered timely to alleviate the secondary neurological impairment after ICH, which was significant to prevent ICH.

[Research on knowledge status and relevant factors of breastfeeding among medical staff in China based on network platform]

From August 1(st) to 7(th), 2017, the breastfeeding knowledge of medical staff were collected from 52 medical health institutions in 29 provinces through a network system. A total of 35 243 questionnaires were included in the study to analyze the current status of breastfeeding knowledge and related factors. The qualified rate of breastfeeding knowledge questionnaires for medical staff in this study was 75.3% (26 546/35 243). Compared with those in the eastern region and those who were mothers, the qualified rate of breastfeeding knowledge of medical staff in the central region or the western region and medical staff who were fathers or expectant parents was lower, with OR (95%CI) values about 0.71 (0.67-0.75), 0.66 (0.61-0.72), 0.63 (0.55-0.72) and 0.87 (0.80-0.95), respectively. Compared with those attaining high school education or below and those with children aged<1 month, the qualified rate of breastfeeding knowledge was higher in medical staff with bachelor's degree, graduate degree or above, and with children aged 1-5, 6-23 and ≥24 months, with OR (95%CI) values about 1.92 (1.80-2.05), 2.16 (1.94-2.42), 2.28 (1.93-2.70), 2.41 (2.06-2.83) and 1.99 (1.72-2.32), respectively.

[HIV early infant diagnosis test in HIV-exposed children in China, 2015-2017]

Objective: To understand the early infant diagnosis (EID) test rate and associated factors in HIV-exposed children in China during 2015-2017. Methods: The follow-up information cards of 12 096 HIV-exposed children for 18 months after birth during 2015-2017 were collected from the Management Information System of China's Prevention of Mother-to-Child Transmission of HIV for a retrospective analysis. The EID test characteristics of HIV exposed children and associated factors were analyzed. Results: From 2015 to 2017, the EID test rate in HIV exposed children increased from 65.6% to 83.4% in China (trend χ(2) P<0.001). The EID test rate within 8 weeks after birth increased from 61.1% to 76.8% (trend χ(2) P<0.001), but the EID positive rate decreased from 8.7% to 3.4% (trend χ(2) P<0.001). The EID positive rate in fatal HIV-exposed children was 47.7%, 36.9% and 36.3% during 2015-2017, respectively, the differences were not significant. EID test rate was associated with ethnic group, living area, survival status and the year reaching 18-month-old of the children. Conclusions: The performance of EID test has been standardized step by step in China. The positive rate of EID test decreased gradually with year. However, the EID test rates in children who were from minority ethnic groups, lived in areas with lower prevalence of HIV infection and died within 18 months after birth were relatively low.

Measurement of the cosmic ray proton spectrum from 40 GeV to 100 TeV with the DAMPE satellite

The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 ¹/₂ years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

Blood Flow Regulates Zebrafish Caudal Vein Plexus Angiogenesis by ERK5-klf2a-nos2b Signaling

BACKGROUND

Vascular network formation induced by angiogenesis plays an important role in many physiological and pathological processes. However, the role of blood flow and underlying mechanisms in vascular network formation, for example for the development of the caudal vein plexus (CVP), is poorly understood.

OBJECTIVE

The aim of this study was to explore the role of ERK5-klf2a-nos2b signaling in the CVP angiogenesis.

METHOD AND RESULTS

In this study on tnnt2a-MO injection and chemical blood flow modulator treatment in zebrafish embryos, we demonstrated that decreased blood flow disrupted CVP formation. The hemodynamic force was quantitatively analyzed. Furthermore, CVP angiogenesis in zebrafish embryos was inhibited by disruption of the blood flow downstream effectors ERK5, klf2a, and nos2b in response to treatment with the ERK5 specific inhibitor and to injection of klf2a-MO, nos2b-MO. Overexpression of klf2a mRNA or nos2b mRNA restored vascular defects in tnnt2a or klf2a morphants. The data suggest that flow-induced ERK5-klf2a-nos2b signaling is involved in CVP angiogenesis in zebrafish embryos.

CONCLUSION

We have demonstrated that blood flow is essential for vascular network formation, specifically for CVP angiogenesis in zebrafish. A novel genetic and mechanical mechanism was discovered in which ERK5 facilitates the integration of blood flow with the downstream klf2a-nos2b signaling for CVP angiogenesis.