[Establishment of a rapid method for detection of influenza A/B virus' antigens].

This study aims to develop a rapid and convenient test card for simultaneous detection of influenza A and influenza B viruses using quantum dot-based immunochromatographic assay. The test card consists of a test strip and a plastic casing. The test strip is composed of absorbent paper, a buffer pad, nitrocellulose membrane (NC membrane), sample pad, quantum dot-labeled antibody pad, and polyvinyl chloride (PVC) board. The NC membrane is coated with mouse monoclonal antibodies against influenza A and influenza B viruses for the T lines (test lines), and reference proteins A and B for the C line (control line). The quantum dot-labeled antibody pad contains mouse monoclonal antibody-quantum dot conjugates against influenza A and influenza B viruses. The results showed that the detection limit of the test card for both viruses ranged from 1.51 ×102 to 2.71×103 TCID50/ml, indicating its sensitivity for accurate detection of influenza A and influenza B viruses without being affected by various variants. The test card exhibited specific reactions with different subtypes of influenza A and influenza B virus culture fluids and showed no cross-reactivity with adenovirus, novel coronavirus, Mycoplasma pneumoniae, respiratory syncytial virus, Staphylococcus aureus, and other pathogens. Overall, the sensitivity and specificity of the test card for simultaneous detection of influenza A and influenza B viruses meet the requirements for clinical use. It offers the advantages of simplicity, rapidity, and no requirement for special equipment, enabling quick auxiliary diagnosis to prevent disease transmission.

Partial cellular reprogramming stably restores the stemness of senescent epidermal stem cells.

OBJECTIVE: Adult stem cell senescence and exhaustion are important drivers of organismal age. Restored stem cell self-renewal has revealed novel therapeutic targets for decreasing the incidence of age-associated diseases (AADs) and prolonging the human health span. Transient ectopic expression of the reprogramming factors Oct3/4, Sox2, Klf4 and c-Myc (collectively known as OSKM) in somatic cells can induce partial cellular reprogramming and effectively ameliorate their age-associated hallmarks. However, how this form of rejuvenation is applied to senescent stem cells remains unknown. MATERIALS AND METHODS: The Integrin-α6highCD71high epidermal stem cells (ESCs) with low self-renewal ability were sorted by flow cytometry and then treated by the interrupted reprogramming induced by transient expression of OSKM. The ability of secondary clones' generation and self-proliferation in vitro, as well as stem cell marker p63, were detected to determine their self-renewal ability. Besides, gene and protein of epidermal cell markers were detected to determine whether their cell identities were retained. Finally, DNA methylation age (eAge) and DNA dehydroxymethylase/methyltransferase were analyzed to explore the alternation of their global DNA methylation pattern during this rejuvenation. RESULTS: The partial reprogramming restored the youthful self-renewal and proliferation in senescent ESCs, including larger secondary clone generation, higher expression of stem cell marker p63 and proliferation marker Ki67, and faster proliferation speed, in each case without abolishing epithelial cellular identity. Moreover, the rejuvenation of adult stem cells could be maintained for 2 weeks after reprogramming factor withdrawal, which was more stable than that of differentiated somatic cells. Additionally, we found that partial reprogramming counteracted the acceleration of eAge in senescent epidermal stem cells and DNA methyltransferase 1 (DNMT1) may play a crucial role in this process. CONCLUSIONS: Partial reprogramming has high therapeutic potential for reversing adult stem cell age, providing an advanced way to treat AADs.

An investigation of the PM2.5 concentrations and cumulative inhaled dose during subway commutes in Changchun, China.

Air quality in subway systems is crucial as it affects the health of passengers and staff. Although most tests of PM2.5 concentrations in subway stations have taken place in public areas, PM2.5 is less understood in workplaces. Few studies have estimated the cumulative inhaled dose of passengers based on real-time changes in PM2.5 concentrations as they commute. To clarify the above issues, this study first measured PM2.5 concentrations in four subway stations in Changchun, China, where measuring points included five workrooms. Then, passengers' exposure to PM2.5 during the whole subway commute (20-30 min) was measured and segmented inhalation was calculated. The results showed that PM2.5 concentration in public places ranged from 50 to 180 µg/m3, and was strongly correlated with outdoors. While the PM2.5 average concentration in workplaces was 60 µg/m3, and it was less affected by outdoor PM2.5 concentration. Passenger's cumulative inhalations in single commuting were about 42 µg and 100 µg when the outdoor PM2.5 concentrations were 20-30 µg/m3 and 120-180 µg/m3, respectively. The PM2.5 inhalation in carriages accounted for the largest proportion of the entire commuting, about 25-40%, because of the longer exposure time and higher PM2.5 concentrations. It is recommended to improve the tightness of the carriage and filter the fresh air to improve the air quality inside. The average daily PM2.5 inhaled by staff was 513.53 µg, which was 5-12 times higher than that of passengers. Installing air purification devices in workplaces and reminding staff to take personal protection can positively protect their health.

Topological Equivalence of Stripy States and Skyrmion Crystals.

Stripy states, consisting of a collection of stripy spin textures, are the precursors of skyrmion crystals (SkXs). The common belief is that stripy states and SkXs are topologically unconnected and that transitions between SkXs and stripy states are phase transitions. Here, we show that both stripy states and SkXs are skyrmion condensates and they are topologically equivalent. By gradually tuning the stripe whose width goes from smaller than to larger than skyrmion-skyrmion separation, the structure of a skyrmion condensate transforms smoothly and continuously from various stripy phases, including helical states and mazes, to crystals, showing that stripy states are topologically connected to SkXs.

Role of SSW on thermal-gradient induced domain-wall dynamics.

We study the thermal gradient (TG) induced domain wall (DW) dynamics in a uniaxial nanowire in the framework of the Stochastic-Landau-Lifshitz-Gilbert equation. TG drives the DW in a certain direction, and DW (linear and rotational) velocities increase with TG linearly, which can be explained by the magnonic angular momentum transfer to the DW. Interestingly, from Gilbert damping dependence of DW dynamics for fixed TG, we find that the DW velocity is significantly smaller even for lower damping, and DW velocity increases with damping (for a certain range of damping) and reaches a maximal value for critical damping which is contrary to our usual desire. This can be attributed to the formation of standing spin wave (SSW) modes (from the superposition of the spin waves and their reflection) together with travelling spin wave (TSW) modes. SSW does not carry any net energy/momentum to the DW, while TSW does. Dampingαcompels the spin current polarization to align with the local spin, which reduces the magnon propagation length and thusαhinders to generate SSWs, and contrarily the number of TSWs increases, which leads to the increment of DW speed with damping. For a similar reason, we observe that DW velocity increases with nanowire length and becomes saturated to maximal value for a certain length. Therefore, these findings may enhance the fundamental understanding as well as provide a way of utilizing the Joule heat in the spintronics (e.g. racetrack memory) devices.

[Research on rapid detection technology of airborne pathogenic organisms based on up-conversion phosphor technology].

Objective: To explore the application of up-conversing phosphor technology (UPT) to detect pathogenic organisms in the air. Methods: The performance of UPT was verified with Staphylococcus aureus, Yersinia pestis and Escherichia coli O157 as simulated strains, including stability, specificity, sensitivity and response time tests; Air particle sampler is used to collect air samples in the field microenvironment test chamber, and UPT is used for detection. At the same time, compared with the traditional culture method, the practicability of UPT is verified. Results: The coefficient of variation in laboratory was 9.62% and 8.02% when the concentration of 107 CFU/ml and 108 CFU/ml were detected by UPT. The results were less than the allowable target, and the detection system had good stability. The specificity of UPT was verified by Staphylococcus aureus. The results showed that no non-Staphylococcus aureus was detected, and the positive detection rate of different kinds of Staphylococcus aureus was 100%. The specificity of the detection system was good. The sensitivity of UPT for detecting Staphylococcus aureus was 104 CFU/ml. Detection sensitivity of Yersinia pestis ≥103 CFU/ml; The detection sensitivity of Escherichia coli O157 is ≥103 CFU/ml, and the response time of UPT to bacteria is within 15 min (all 10 min 15 s). The detection results of bacteria contentration in the air of the on-site microenvironment test cabin by UPT showed that when the concentration of Escherichia coli O157 in the air reached above 104 CFU/m3, the detection results of UPT were positive, and with the increase of air concentration, the numerical concentration measured by UPT showed an upward trend, which was positively correlated with the concentration of bacteria in the air. Conclusion: UPT may be feasible as a rapid method to evaluate the species and contentration of pathogenic organisms in the air.

[Genetic mutation profiles for children with congenital hypothyroidism in Fujian province].

Objective: To explore the mutation characteristics of pathogenic genes in children with congenital hypothyroidism (CH) in Fujian. Methods: The clinical data of 116 unrelated CH children diagnosed in Fujian Provincial Maternal and Child Health Hospital from January 2019 to September 2020 were retrospectively analyzed, including 50 females and 66 males, with an average age of (20±10) days at diagnosis. Targeted exome sequencing technology was used to detect the mutation frequency, type and distribution characteristics of 29 genes related to thyroxine synthesis or thyroid development. Results: Three hundred and fifty-one potential functional mutations were detected in 105 of 116 CH patients, with a detection rate of 90.5% (105/116). DUOX2 (66.4%, 77/116) was the most frequent mutated gene, followed by TG (23.3%, 27/116), DUOXA1 (23.3%, 27/116), and TPO (12.1%, 14/116), which were all involved in thyroid hormone synthesis. Among the 105 children with CH, 70 cases carried double allele mutation. Except for 3 cases of thyroid dysplasia related genes (2 cases of TSHR and 1 case of GLIS3), the rest were also related to thyroid hormone synthesis. The gene with the highest carrier rate was DUOX2 (68.8%, 59/70), followed by TG (8.6%, 6/70), TPO (4.3%, 3/70), DUOXA2 (1.4%, 1/70) and DUOXA1 (1.4%, 1/70). Conclusion: The main mutated genes in CH children in Fujian are the key genes involved in thyroid hormone synthesis, such as DUOX2, TG and TPO.

A theory of unusual anisotropic magnetoresistance in bilayer heterostructures.

The observation of magnetoresistance (MR) varying with the rotation of magnetization in the plane perpendicular to the electric current is an important discovery in spintronics in recent years. The famous conventional anisotropic MR (AMR) says that the resistance of a polycrystalline magnetic material must depend on magnetization component along the current direction only, thus cannot account for this newly observed unusual AMR (UAMR). This UAMR leads to the notion of the spin-Hall MR (SMR) in the famous SMR theory. However, the SMR theory may only explain UAMR observed in heavy-metal/magnetic-insulator bilayers, not other types of bilayers. Here, we present a two-vector theory that can explain not only all existing experiments on the unusual angular dependence of longitudinal and transverse resistivity when the magnetization rotates in three mutually perpendicular planes, but also how three amplitudes of MR angular oscillation are related to each other. The theory is very general and its correctness depends only on the assumption that the magnetization and interfacial field are the only vectors affecting electron transport besides of other scalar variables such as the temperatures and impurities. Experiments that can test this theory against the SMR theory are also proposed.

[Preliminary MRI evaluation of anterior repositioning splint in treatment of disc displacement with reduction of temporomandibular joint].

Objective: MRI images were used to study the efficacy of anterior repositioning splint (ARS) in the treatment of different types of disc displacement with reduction (DDWR) in temporomandibular joint. Methods: From September 2020 to December 2021, 26 patients with DDWR were enrolled in the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Zhengzhou University. There were 5 males and 21 females with an average age of (20.8±5.8) years. ARS was used for 3-6 months. The changes of joint clicking, opening type and joint pain before and after treatment were compared. The changes of disc position, disc-condyle angle and condylar bone mass before and after treatment were compared by MRI. Paired t-test was performed on the disc-condyle angle before and after treatment, Fisher's exact test was performed on the change of disk position, and other count data were expressed as rate (%). Results: After ARS treatment, the effective rates of joint clicking,abnormal opening, joint pain and disc displacement were 97%(35/36), 14/18, 7/9 and 95%(36/38). MRI analysis found that there was a significant difference between the disc position before and after treatment (P<0.001), MRI analysis showed that the anterior disc displacement (48%, 25/52) and the anterolateral disc displacement (17%, 9/52) were the most common before treatment. In contrast, the normal superior disc (75%, 39/52) and the anterior disc displacement (17%, 9/52) were the most common after treatment, no significant changes were seen after treatment in the anteromedial disc displacement. The disc-condylar angle was (36.09±19.02) ° before ARS treatment and (3.94±10.12) ° after ARS treatment(t=9.23, P<0.001). After treatment, 46% (12/16) of the patients showed new bone formation, and the height of the condyle recovered. Conclusions: The clinical efficacy of ARS in the treatment of anterior disc displacement and anterolateral displacement of temporomandibular joint is remarkable, which can restore the disc-condylar relationship of most patients with indications.

[Progress in researches on the effect of artificial light at night on infertility].

Infertility is a serious social and public health problem, and the causes of infertility are also the focus of many researchers in recent years. Since the invention of the electric light, people's exposure to night light has increased rapidly, and the adverse effects on human health have also begun to enter the vision of researchers. Studies have shown that artificial lighting at night can affect the circadian rhythm of organisms and the secretion of melatonin (melatonin), and regular circadian rhythms and sufficient melatonin are conducive to successful reproduction. This article reviews the current research status of the effects of artificial lighting at night on infertility in recent years, which provides a new direction for researchers to study the influencing factors of infertility.

A theory of skyrmion crystal formation.

A generic theory about skyrmion crystal (SkX) formation in chiral magnetic thin films and its fascinating thermodynamic behaviours is presented. A chiral magnetic film can have many metastable states with an arbitrary skyrmion density up to a maximal value when the parameter κ, which measures the relative Dzyaloshinskii-Moriya interaction (DMI) strength, is large enough. The lowest energy state of an infinite film is a long zig-zag ramified stripe skyrmion occupying the whole film in the absence of a magnetic field. Under an intermediate field perpendicular to the film, the lowest energy state has a finite skyrmion density. This is why a chiral magnetic film is often in a stripy state at a low field and a SkX only around an optimal field when κ is above a critical value. The lowest energy state is still a stripy helical state no matter with or without a field when κ is below the critical value. The multi-metastable states explain the thermodynamic path dependences of the various metastable states of a film. The decrease of the κ value with the temperature explains why SkXs become metastable at low temperatures in many skyrmion systems. These findings open a new avenue for SkX manipulation and skyrmion-based applications.

[Comparative study of three scores in predicting the death risk of severe burn patients].

Objective: To explore the predictive values of the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score on the death risk of severe burn patients. Methods: A retrospective case series study was conducted. From February 2018 to November 2019, 260 severe burn patients who met the inclusion criteria were admitted to the Department of Burns of the First Affiliated Hospital of Nanchang University, including 158 males and 102 females, aged 36 (3, 53) years. According to the final outcome, the patients were divided into survival group (n=229) and death group (n=31). Data of patients were compared and statistically analyzed with chi-square test or Mann-Whitney U test between the two groups, including the gender, age, cause of burn, site of burn, total burn area, depth of burn, combined inhalation injury, and combined underlying diseases on admission, and the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score calculated based on part of the aforementioned data. The Kendall tau-b coefficient method was used to analyze the consistency of the above-mentioned three scores in 260 severe burn patients. The receiver operating characteristic (ROC) curves of the above-mentioned three scores predicting the death risk of 260 severe burn patients were drawn, and the area under the curve (AUC), the optimal threshold, and the sensitivity and specificity under the optimal threshold were calculated. The quality of AUC of the above-mentioned three scores was compared by Delong test. Results: The gender, site of burn, and depth of burn of patients between the two groups were all similar (P>0.05). The age, total burn area, proportion of flame burn, proportion of combined inhalation injury, and proportion of combined underlying diseases of patients in death group were significantly higher than those in survival group (with Z values of 5.53 and 17.78, respectively, χ2 values of 16.23, 15.89, and 17.78, respectively, P<0.01); the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score of patients in death group were 142 (115, 155), 7 (5, 7), 2 (2, 3), all significantly higher than 64 (27, 87), 1 (0, 3), 0 (0, 1) in survival group (with Z values of 7.91, 7.64, and 7.61, respectively, P<0.01). In 260 severe burn patients, the results between the modified Baux score and Ryan score, modified Baux score and Belgian Outcome in Burn Injury score, Ryan score and Belgian Outcome in Burn Injury score were significantly consistent (with Kendall tau-b coefficients of 0.75, 0.71, and 0.86, respectively, P<0.01). The AUCs of ROC curves of the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score for predicting the death risk of 260 severe burn patients were 0.92, 0.89, and 0.85, respectively (with 95% confidence intervals of 0.86-0.98, 0.83-0.95, and 0.78-0.93, respectively, P<0.01); the optimal thresholds were 106.5, 4.5, and 1.5 points, respectively; the sensitivity under the optimal threshold were 88.5%, 76.9%, and 73.1%, respectively, and the specificity under the optimal threshold were 88.5%, 87.2%, and 86.3%, respectively. The modified Baux score was similar to Belgian Outcome in Burn Injury score in the AUC quality (z=1.25, P>0.05), which were both significantly better than the AUC quality of Ryan score (with z values of 2.35 and 2.11, respectively, P<0.05). Conclusions: The modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score have good ability in predicting the death risk of severe burn patients. From the perspective of clinical practice, the modified Baux score is more suitable as a predictive tool for the prognosis of severe burn patients.

Differentiating infected focal liver lesions from malignant mimickers: value of ultrasound-based radiomics.

AIM: To establish an ultrasound-based radiomics model through machine learning methods and then to assess the ability of the model to differentiate infected focal liver lesions from malignant mimickers. MATERIALS AND METHODS: A total of 104 patients with infected focal liver lesions and 485 patients with malignant hepatic tumours were included, consisting of hepatocellular carcinoma (HCC), cholangiocarcinoma (CC), combined hepatocellular-cholangiocarcinoma (cHCC-CC), and liver metastasis. Radiomics features were extracted from grey-scale ultrasound images. Feature selection and predictive modelling were carried out by dimensionality reduction methods and classifiers. The diagnostic effect of the prediction mode was assessed by receiver operating characteristic (ROC) curve analysis. RESULTS: In total, 5,234 radiomics features were extracted from grey-scale ultrasound image of every focal liver lesion. The ultrasound-based radiomics model had a favourable predictive value for differentiating infected focal liver lesions from malignant hepatic tumours, with an area under the curve (AUC) of 0.887 and 0.836 (HCC group), 0.896 and 0.766 (CC group), 0.944 and 0.754 (cHCC-CC group), 0.918 and 0.808 (liver metastasis group), and 0.949 and 0.745 (malignant hepatic tumour group) for the training set and validation set, respectively. CONCLUSIONS: Ultrasound-based radiomics is helpful in differentiating infected focal liver lesions from malignant mimickers and has the potential for use as a supplement to conventional grey-scale ultrasound and contrast-enhanced ultrasound (CEUS).

[Treatment strategy of gastrointestinal stromal tumors in the background of COVID-19].

COVID-19, caused by SARS-COV-2, has the characteristics of world epidemic, highly infectious and large base of death. In China, transmission route of SARS-COV-2 has been contained so effectively that COVID-19 has been well controlled due to the proactive national prevention and control strategy. However, not only does it bring a huge impact on the existing medical structure model, but also an objective impact on the treatment of patients with chronic diseases such as malignant tumors. Based on the progress reported in the domestic and international literatures and the actual management experience of our team, this paper reflects on the treatment strategies for patients with gastrointestinal stromal tumor (GIST) during the epidemic period of COVID-19. We focus on risk stratification for primary GIST and forming treatment strategies accordingly. Major considerations include the impact of delayed operation, the burden of medical resources, the waiting time for elective operation, and the principle of emergency operation. In addition, we focus on the level of evidence for non-surgical approaches with a view to developing a holistic strategy of "priority management principles" to guide clinical treatment in the context of limited resources and different GIST priorities.

The morphological and histological study of chicken left ovary during growth and development among Hy-line brown layers of different ages.

Chicken ovaries are known to develop asymmetrically and only the left ovary fully develops. Although both have been greatly investigated, a gap in scientific reports is still felt between 2-mo-old and sexual maturity. In this study, we aimed at investigating the changes in components that occur during growth to analyze the morphohistological correlation between the left ovary and the follicle development at different age stages in Gallus domesticus. The ovaries were harvested from 60 chickens aged 1 and 3-wk-old, 1, 2, 3, and 4-mo-old (n = 10 per age group), then fixed in AAF solution. Hematoxylin-and Eosin protocol was used to stain the tissue for microscopic observations. Results revealed that the left ovary exhibited an ovarian tissue, a site of follicular growth that displayed various shapes from smooth to greatly indented as the follicles differentiated. Atretic follicles at various regression stages were noticed frequently as the chicks grew in age from 3-wk-old onward along with their differentiation. Rete ovarii, remnants from the male homologs were observed throughout the whole study showing epoöphoron, connecting rete, and gland-like structures that tend to diminish with age. The feature of the left ovary is closely related to the follicular developmental stage, and the bigger and differentiated the follicles are, the more indented and irregular its epithelium appears. Atresia is a normal physiological process that we observed throughout the whole study. Also that, rete ovarii do not spontaneously arise in the ovary but it develops and grows in juvenile chicken as well as in adult ones.

[Anatomical controversies involved in radical resection of rectal cancer].

The concept of total mesorectal resection provides a quality control standard that can be followed for radical resection of rectal cancer, but some anatomical problems are still controversial. Compared with traditional open surgery, laparoscopic radical rectal surgery has better surgical vision, better neurological protection, better operating space. However, if the surgeon has insufficient understanding of the anatomy, collateral damage may occur, such as uncontrollable bleeding during the operation, postoperative urination and defecation dysfunction and so on. Based on the interpretation of the researches at home and abroad, combined with the clinical experience, we elucidate some associated issues, including anatomic variation of inferior mesenteric vessels, the controversy of inferior mesenteric artery ligation plane, the controversy of lymph node dissection in No. 253, the anatomical variation of middle rectal artery, and the anatomical controversy of lateral lymph node dissection in rectal cancer, in order to provide better cognitive process for the clinical front-line surgeons.