[Effects of cadmium chloride on testicular autophagy and blood-testis barrier integrity in prepubertal male rats]

Objective: To study the effects of cadmium chloride (CdCl(2)) exposure on testicular autophagy levels and blood-testis barrier integrity in prepubertal male SD rats and testicular sertoli (TM4) cells. Methods: In July 2021, 9 4-week-old male SD rats were randomly divided into 3 groups: control group (normal saline), low dose group (1 mg/kg·bw CdCl(2)) and high dose group (2 mg/kg·bw CdCl(2)), and were exposed with CdCl(2) by intrabitoneal injection. 24 h later, HE staining was used to observe the morphological changes of testis of rats, biological tracer was used to observe the integrity of blood-testis barrier, and the expression levels of microtubule-associated protein light chain 3 (LC3) -Ⅰ and LC3-Ⅱ in testicular tissue were detected. TM4 cells were treated with 0, 2.5, 5.0 and 10.0 μmol/L CdCl(2) for 24 h to detect the toxic effect of cadmium. The cells were divided into blank group (no exposure), exposure group (10.0 μmol/L CdCl(2)), experimental group[10.0 μmol/L CdCl(2)+60.0 μmol/L 3-methyladenine (3-MA) ] and inhibitor group (60.0 μmol/L 3-MA). After 24 h of treatment, Western blot analysis was used to detect the expression levels of LC3-Ⅱ, ubiquitin binding protein p62, tight junction protein ZO-1 and adhesion junction protein N-cadherin. Results: The morphology and structure of testicular tissue in the high dose group were obvious changed, including uneven distribution of seminiferous tubules, irregular shape, thinning of seminiferous epithelium, loose structure, disordered arrangement of cells, abnormal deep staining of nuclei and vacuoles of Sertoli cells. The results of biological tracer method showed that the integrity of blood-testis barrier was damaged in the low and high dose group. Western blot results showed that compared with control group, the expression levels of LC3-Ⅱ in testicular tissue of rats in low and high dose groups were increased, the differences were statistically significant (P<0.05). Compared with the 0 μmol/L, after exposure to 5.0, 10.0 μmol/L CdCl(2), the expression levels of ZO-1 and N-cadherin in TM4 cells were significantly decreased, and the expression level of p62 and LC3-Ⅱ/LC3-Ⅰ were significantly increased, the differences were statistically significant (P<0.05). Compared with the exposure group, the relative expression level of p62 and LC3-Ⅱ/LC3-Ⅰ in TM4 cells of the experimental group were significantly decreased, while the relative expression levels of ZO-1 and N-cadherin were significantly increased, the differences were statistically significant (P<0.05) . Conclusion: The mechanism of the toxic effect of cadmium on the reproductive system of male SD rats may be related to the effect of the autophagy level of testicular tissue and the destruction of the blood-testis barrier integrity.

[Incidence and prognosis of olfactory and gustatory dysfunctions related to infection of SARS-CoV-2 Omicron strain: a national multi-center survey of 35 566 population]

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.

Two ground-state bright solitons in fractional-order spin-orbit-coupled Bose-Einstein condensates

We study two types of bright solitons in zero and non-zero detuning spin-orbit-coupled (SOC) Bose-Einstein condensates in fractional effect by variational and imaginary-time evolution method. The results show that the variation of SOC with fractional kinetic energy operator affects the existence and form of solitons. In particular, we found that SOC strengthγ=1.0could be a transition point. In other words, forγ<1.0andγ⩾1.0, the soliton states and pseudo-spin polarization in non-zero detuning show opposite changes. In addition, moving bright solitons with zero and non-zero detuning are studied.

[Analysis of management efficacy in patients with heavy menstrual bleeding associated with antithrombotic therapy]

Objective: To evaluate different methods' efficacy of controlling acute bleeding and managing long-term menstruation in patients with heavy menstrual bleeding (HMB) associated with antithrombotic therapy. Methods: The clinical data of 22 cases with HMB associated with antithrombotic therapy admitted to Peking University People's Hospital from January 2010 to August 2022 were analyzed, aged 39 years old (26-46 years). Changes in menstrual volume, hemoglobin (Hb), and quality of life were collected after control of acute bleeding and long-term menstrual management. Menstrual volume was assessed by pictorial blood assessment chart (PBAC), and quality of life was assessed by menorrhagia multi-attribute scale (MMAS). Results: (1) Treatment of acute bleeding: of the 22 cases with HMB associated with antithrombotic therapy, 16 cases were treated in our hospital and 6 in other hospital for emergency bleeding; of the 16 cases treated in our hospital, 3 underwent emergency intrauterine Foley catheter balloon compression due to severe bleeding (Hb decreased by 20 to 40 g/L within 12 hours). Of the 22 cases with antithrombotic therapy-related HMB, 15 (including 2 cases with severe bleeding) underwent emergency aspiration or endometrial resection, and intraoperative placement of levonorgestrel-releasing intrauterine system (LNG-IUS) followed by a significant reduction in bleeding volume; 3 cases had controlled acute bleeding after rivaroxaban dose reduction and continued observation; 2 cases were given gonadotropin-releasing hormone agonists to control acute bleeding in other hospital, of which 1 case was temporarily treated with periodic blood transfusion, and the other one patient underwent total hysterectomy; and 2 cases had temporary amenorrhea with oral mifepristone after intrauterine balloon compression or oral norethindrone. (2) Long-term menstrual management: of the 22 cases with antithrombotic therapy-related HMB, 15 had LNG-IUS placement and 12 had LNG-IUS placement for 6 months, and menstrual volume was significantly reduced [PBAC scores were 365.0 (272.5-460.0) vs 25.0 (12.5-37.5), respectively; Z=4.593, P<0.001], Hb was significantly increased [91.5 g/L (71.8-108.2 g/L) vs 128.5 g/L (121.2-142.5 g/L); Z=4.695, P<0.001], and quality of life was significantly improved [MMAS scores were 415.0 (327.5-472.5) vs 580.0 (570.0-580.0), respectively; Z=-3.062, P=0.002] before placement compared with 6 months after placement. Three rivaroxaban dose reduction patients' PBAC scores decreased by 20 to 35 but remained >100, and perceived quality of life did not change significantly. Two cases with temporary amenorrhea treated with oral mifepristone felt significantly improved quality of life, and the MMAS scores increased by 220 and 180, respectively. Conclusion: Intrauterine Foley catheter balloon compression, aspiration or endometrial ablation could be used to control acute bleeding in patients with antithrombotic therapy-related HMB, and LNG-IUS for long-term management could reduce menstrual volume, increase hemoglobin, and improve the quality of life of patients.

Braille recognition by E-skin system based on binary memristive neural network

Braille system is widely used worldwide for communication by visually impaired people. However, there are still some visually impaired people who are unable to learn Braille system due to various factors, such as the age (too young or too old), brain damage, etc. A wearable and low-cost Braille recognition system may substantially help these people recognize Braille or assist them in Braille learning. In this work, we fabricated polydimethylsiloxane (PDMS)-based flexible pressure sensors to construct an electronic skin (E-skin) for the application of Braille recognition. The E-skin mimics human touch sensing function for collecting Braille information. Braille recognition is realized with a neural network based on memristors. We utilize a binary neural network algorithm with only two bias layers and three fully connected layers. Such neural network design remarkably reduces the calculation burden and, thus, the system cost. Experiments show that the system can achieve a recognition accuracy of up to 91.25%. This work demonstrates the possibility of realizing a wearable and low-cost Braille recognition system and a Braille learning-assistance system.

[Effects of different accompanying symptoms of obstructive sleep apnea on the risk of cardiovascular and cerebrovascular and diabetes events]

Objective: To investigate the effects of different accompanying symptoms on the risk of cardiovascular and cerebrovascular and diabetes events in patients with obstructive sleep apnea (OSA). Methods: Patients diagnosed with OSA in the sleep center of Tangdu Hospital from January 4, 2011 to December 28, 2016 were retrospectively collected and divided into four groups according to accompanying symptoms: group A included OSA patients without insomnia and excessive daytime sleepiness (EDS), group B included OSA patients with insomnia, group C included OSA patients with EDS and group D included OSA patients with insomnia and EDS. Patients were followed up by telephone for 6 to 11 years. Outcome measures were composite cardiovascular and cerebrovascular and diabetes events (including new onset or recurrent heart disease, cerebral infarction, cerebral hemorrhage, newly diagnosed hypertension and diabetes). Kaplan-Meier method was used to draw survival curves, log-rank test was performed to compare the prognosis of OSA patients with insomnia and/or EDS symptoms, and multivariate Cox proportional hazards model was constructed to analyze the influencing factors of adverse outcome events in OSA patients. Results: Five hundred and four patients with OSA were included, and 307 patients [274 males and 33 females, aged (49±11) years] completed the follow-up, including 27 patients in group A, 143 patients in group B, 27 patients in group C, and 110 patients in group D. After a median follow-up of 7.7 years, 78 patients developed cardiovascular and cerebrovascular and diabetes events. Outcome events occurred in 1 patient (3.70%) in group A, 30 (20.98%) in group B, 10 (37.04%) in group C, and 37 (33.64%) in group D. Compared with patients in group A, there was a statistically significant difference in the incidence of outcome events in groups B (P=0.034), C (P=0.004), and D (P=0.003). After adjusting for age, sex, body mass index, apnea-hypopnea index, baseline cardiovascular and cerebrovascular risk factors and subsequent continuous positive airway pressure therapy, patients in group C (HR=9.67, 95%CI: 1.23-76.37, P=0.031) and group D (HR=11.35, 95%CI: 1.55-83.43, P=0.017) had an increased risk of cardiovascular and cerebrovascular and diabetes events when compared with group A. Conclusions: In OSA patients with successful long-term follow-up, insomnia and EDS symptoms are risk factors for the development of cardiovascular and cerebrovascular and diabetes events. Insomnia and EDS symptoms should be evaluated in patients with OSA during clinical practice to find the cause and carry out the targeted intervention.

[Application value of image fusion technology in transcatheter aortic valve implantation]

Objective: To analysis the application value of image fusion technology in transcatheter aortic valve implantation (TAVI). Methods: A total of 35 patients underwent trans-femoral TAVI using the first-generation VENUS-A valve in Heart Center of Henan Provincial People's Hospital from January 2020 to May 2021 were analyzed retrospectively. Among them, there were 21 males and 14 females, aged from 64 to 81 years, with a mean (SD) of (71.37±5.66) years. They were divided into conventional group (n=22) and fusion group (n=13), according to whether image fusion technology was used during operation. The preoperative general data, intraoperative data, differences of postoperative renal function and residence time in intensive care unit (ICU) were analyzed and compared between the two groups. The postoperative echocardiography and 12 lead ECG were observed. Results: All 35 patients in this study were with severe aortic stenosis, of which, 10 patients were complicated with moderate to severe regurgitation. Compared with the conventional group, the intraoperative fusion group had fewer angiography times [3.0 (3.0, 4.0) vs 5.0 (5.0, 6.0)], X-ray absorbed dose [342.0 (44.5) mGy vs 388.4 (71.0) mGy], and contrast dosage [(73.5±10.5) ml vs (90.3±10.3) ml], and shorter rapid pacing time [(14.0±1.6) seconds vs (16.5±2.0) seconds] (all P<0.05). There was no significant differences in X-ray irradiation time, operation time, sizing of the pre-dilated balloon, valve implantation depth and other indicators (all P>0.05). There was no significant differences in ICU retention time and postoperative renal function (all P>0.05). Postoperative echocardiography showed that the function of aortic valve was good, with mild perivalvular leakage in 2 cases in the conventional group and 1 case in the fusion group; and one patient was implanted with permanent pacemaker after TAVI in the conventional group. Conclusion: Image fusion technology simplifies the TAVI process, shortens the ventricular pacing time and reduces the dosage of X-ray and contrast, and has certain clinical application value.

[Efficacy and influencing factors of surgery combined with neoadjuvant chemoradiotherapy in the treatment of children with non-orbital head and neck rhabdomyosarcoma]

Objective: To evaluate the efficacy and influencing factors of surgery combined with neoadjuvant chemoradiotherapy in the treatment of children with non-orbital head and neck rhabdomyosarcoma (HNRMS). Methods: Information from 45 children diagnosed as non-orbital HNRMS and subjected to surgery combined with neoadjuvant chemoradiotherapy in Beijing Children's Hospital affiliated to Capital Medical University from August 2017 to July 2021 was analyzed. The patients included 25 males and 20 females, aged from 1 to 17 years old. The primary tumor site, pathological subtype, clinical stage, risk group, therapeutic regimen, resection range and outcome of all cases were also collected. The survival curves were made using the Kaplan-Meier method and the potential prognostic factors were investigated by Cox regression analysis. Results: Fifteen (33.3%) of 45 children achieved negative surgical margin under complete tumor resection. The postoperative pathological results showed that there were 20 cases of embryonic subtype, 19 cases of alveolar subtype and 6 cases of spindle sclerosis subtype. The postoperative follow-up time ranged from 4 to 71 months, with a median of 26 months. During the follow-up period, 13 children died, among whom brain metastasis was the most common cause of death, accounting for 7/13. The 3-year overall survival rate was 67.6%. Multivariate analysis showed that non-embryonic subtype (HR=6.26, 95%CI: 1.52-25.87, P=0.011) and failure to reach R0 resection (HR=9.37, 95%CI: 1.18-74.34, P=0.034) were independent risk factors affecting overall survival rate. Conclusion: Surgery combined with neoadjuvant chemoradiotherapy can offer a good efficacy for children with non-orbital HNRMS. Non-embryonic subtype and resection without negative operative microscopic margins are independent risk factors for poor prognosis, and brain metastasis is the main cause of death in these children.

A Co-Designed Neuromorphic Chip With Compact (17.9K F2) and Weak Neuron Number-Dependent Neuron/Synapse Modules

Many efforts have been made to improve the neuron integration efficiency on neuromorphic chips, such as using emerging memory devices and shrinking CMOS technology nodes. However, in the fully connected (FC) neuromorphic core, increasing the number of neurons will lead to a square increase in synapse & dendrite costs and a high-slope linear increase in soma costs, resulting in an explosive growth of core hardware costs. We propose a co-designed neuromorphic core (SRCcore) based on the quantized spiking neural network (SNN) technology and compact chip design methodology. The cost of the neuron/synapse module in SRCcore weakly depends on the neuron number, which effectively relieves the growth pressure of the core area caused by increasing the neuron number. In the proposed BICS chip based on SRCcore, although the neuron/synapse module implements 1∼16 times of neurons and 1∼66 times of synapses, it only costs an area of 1.79 × 10⁷ F², which is 7.9%∼38.6% of that in previous works. Based on the weight quantization strategy matched with SRCcore, quantized SNNs achieve 0.05%∼2.19% higher accuracy than previous works, thus supporting the design and application of SRCcore. Finally, a cross-modeling application is demonstrated based on the chip. We hope this work will accelerate the development of cortical-scale neuromorphic systems.

[Cadmium induces apoptosis of mouse spermatocytes (GC-2 spd) by promoting mitochondrial fission]

Objective: To study the underlying mechanism of cadmium-induced apoptosis of mouse spermatocytes (GC-2 spd) . Methods: In March 2021, GC-2 spd cells were exposed to different concentrations of CdCl(2) for 24 hours, namely 5 μmol/L CdCl(2) (low-dose) group and 10 μmol/L CdCl(2) (high-dose) group, and unexposed GC-2 spd cells were used as control group. Mitochondrial morphology was observed in the cells stained with Mito-Track Red CMXRos fluorescent probes by confocal microscopy and the mitochrondrial membrane potential was measured by flow cytometry with JC-1 fluorescent probes. Mitochrondrial proteins, cytosolic proteins and total cellular proteins of GC-2 spd cells were extracted using cell mitochondria isolation kit and RIPA buffer, respectively. The expression of mitochondrial homeostasis regulatory proteins (FIS1 and OPA1), and apoptosis-related proteins (Cytochrome c and cleaved Caspase-3) were examined by Western blot. Results: Compared with the cells in the control group, the relative ratio of JC-1 red/green fluorescence signal in the cells of the low-dose and high-dose CdCl(2) groups decreased significantly (0.740±0.071, 0.570±0.028), with a statistically significant difference (P=0.017, 0.004) ; The morphology of mitochondria changed from long tube to point, and the proportion of cells containing point mitochondria increased significantly (45.1%±3.7% and 25.7%±4.9%), the difference was statistically significant (P=0.005, 0.001) ; The relative expression level of mitochondrial FIS1 in cells of low and high dose CdCl(2) groups was significantly higher (1.271±0.120, 1.693±0.155), the difference was statistically significant (P=0.046, 0.000) ; The relative expression level of OPA1 decreased significantly (0.838±0.050, 0.682±0.040), and the difference was statistically significant (P=0.049, 0.001). Compared with the control group, the relative expression level of cytochrome c protein in the cytoplasm of cells in the low dose group of CdCl(2) was not significantly increased (1.249±0.151), and the difference was not statistically significant (P=0.075). However, the relative expression level in the cytoplasm of cells in the high dose group of CdCl(2) was significantly increased (2.355±0.110), and the difference was statistically significant (P=0.000) ; The relative expression level of Cytochrome c in mitochondria of low and high dose CdCl(2) groups decreased significantly (0.681±0.043, 0.619±0.114), with a statistically significant difference (P=0.004, 0.001) ; Moreover, the level of cleaved Caspase-3 protein in cells gradually increased (5.486±0.544, 11.493±1.739), the difference was statistically significant (P=0.004, 0.000) . Conclusion: Cadmium induced cleaved Caspase-3 mediated apoptosis of GC-2 spd cells via promoting mitochrondrial fission and the release of Cytochrome c from the mitochrondria to the cytosol.

[The feasibility study of objective evaluation of the severity of motion sickness by quantitative analysis of the facial skin color]

Objective: To explore the feasibility of applying quantitative analysis of the facial skin color to evaluate the severity of motion sickness objectively and to seek objective indicators that can reflect the severity of motion sickness. Methods: Motion sickness was induced in 51 male adult subjects recruited at the Air Force Medical University by Coriolis acceleration stimulation, and facial skin colorimetric values were acquired using a portable spectrophotometer at five time points: before stimulation and at 0 min, 10 min, 20 min and 30 min after the end of stimulation. The Graybiel rating scales were applied to assess the severity of motion sickness in subjects at each time point after stimulation, and the correlation between the magnitude of change in each colorimetric value and the maximum Graybiel's score was analyzed. The ROC curves were used to compare the evaluation performance of colorimetric value indicators which could reflect the severity of motion sickness. Results: Each colorimetric value in the CIE-L^*a^*b^* color system changed significantly after exposure to provocative motion stimuli, and the trend was consistent with the typical sign of pallor in motion sickness. The magnitudes of the increase in the colorimetric value CIE-L^*, the decrease in CIE-a^*, and the increase in CIE-b^* were all significantly and positively correlated with the maximum of Graybiel's scores (r=0.490 0, P=0.000 3; r=0.549 3, P<0.000 1; r=0.540 9, P<0.000 1). Comparing the performance of three colorimetric indicators to assess the severity of motion sickness, CIE-a^* had an area under the ROC curve of 0.875 0, a sensitivity of 85.71%, and a specificity of 87.50%, which was better than CIE-L^* and CIE-b^*. Conclusions: The CIE-L^*a^*b^* colorimeter values can be considered as objective indicators of the severity of motion sickness, among which the colorimetric indicator CIE-a^* has the most diagnostic significance, and the method of quantitative analysis of the facial skin color can provide a new reference for the objective evaluation of the severity of motion sickness.

[Effects of transient receptor potential vanilloid type 4-specific activator on human vascular endothelial cell functions and blood supply of rat perforator flap and its mechanism]

Objective: To analyze the effects of transient receptor potential vanilloid type 4 (TRPV4) activation on the function and endothelial-to-mesenchymal transition (EndMT) of human umbilical vein endothelial cells (HUVECs), as well as to explore the effects of TRPV4 activation on blood perfusion and survival of rat perforator flap and the mechanism. Methods: The experimental research methods were used. The 3rd to 6th passages of HUVECs were used for experiments and divided into 0.5 μmol/L 4α-phorbol 12, 13-didecanoate (4αPDD) group, 1.0 μmol/L 4αPDD group, 3.0 μmol/L 4αPDD group, 10.0 μmol/L 4αPDD group, and phosphate buffer solution (PBS) group, which were cultivated in corresponding final molarity of 4αPDD and PBS, respectively. The cell proliferation activity at 6 and 12 h of culture was detected using cell counting kit-8 (CCK-8). Another batch of cells was acquired and divided into PBS group, 1 μmol/L 4αPDD group, and 3 μmol/L 4αPDD group, which were treated similarly as described before and then detected for cell proliferation activity at 6, 12, 24, and 48 h of culture. The residual scratch area of cells at post scratch hour (PSH) 12, 24, and 48 was detected by scratch test, and the percentage of the residual scratch area was calculated. The number of migrated cells at 24 and 48 h of culture was detected by Transwell experiment. The tube-formation assay was used to measure the number of tubular structures at 4 and 8 h of culture. The protein expressions of E-cadherin, N-cadherin, Slug, and Snail at 24 h of culture were detected by Western blotting. All the sample numbers in each group at each time point in vitro experiments were 3. A total of 36 male Sprague-Dawley rats aged 8 to 10 weeks were divided into delayed flap group, 4αPDD group, and normal saline group according to the random number table, with 12 rats in each group, and iliolumbar artery perforator flap models on the back were constructed. The flap surgical delay procedure was only performed in the rats in delayed flap group one week before the flap transfer surgery. Neither rats in 4αPDD group nor normal saline group had flap surgical delay; instead, they were intraperitoneally injected with 4αPDD and an equivalent mass of normal saline, respectively, at 10 min before, 24 h after, and 48 h after the surgery. The general state of flap was observed on post surgery day (PSD) 0 (immediately), 1, 4, and 7. The flap survival rates were assessed on PSD 7. The flap blood perfusion was detected by laser speckle contrast imaging technique on PSD 1, 4, and 7. The microvascular density in the flap's choke vessel zone was detected by immunohistochemical staining. All the sample numbers in each group at each time point in vivo experiments were 12. Data were statistically analyzed with analysis of variance for factorial design, analysis of variance for repeated measurement, one-way analysis of variance, least significant difference t test, and Bonferroni correction. Results: At 6 and 12 h of culture, there were no statistically significant differences in cell proliferation activity in the overall comparison among PBS group, 0.5 μmol/L 4αPDD group, 1.0 μmol/L 4αPDD group, 3.0 μmol/L 4αPDD group, and 10.0 μmol/L 4αPDD group (P>0.05). At 6, 12, 24, and 48 h of culture, there were no statistically significant differences in cell proliferation activity in the overall comparison among PBS group, 1 μmol/L 4αPDD group, and 3 μmol/L 4αPDD group (P>0.05). At PSH 12, the percentages of the residual scratch area of cells in 1 μmol/L 4αPDD group and 3 μmol/L 4αPDD group were close to that in PBS group (P>0.05). At PSH 24 and 48, compared with those in PBS group, the percentages of the residual scratch area of cells in 3 μmol/L 4αPDD group were significantly decreased (with t values of 2.83 and 2.79, respectively, P<0.05), while the percentages of the residual scratch area of cells in 1 μmol/L 4αPDD group showed no significant differences (P>0.05). At 24 h of culture, the number of migrated cells in 1 μmol/L 4αPDD group and 3 μmol/L 4αPDD group were close to that in PBS group (P>0.05). At 48 h of culture, the number of migrated cells in 1 μmol/L 4αPDD group and 3 μmol/L 4αPDD groups were significantly greater than that in PBS group (with t values of 6.20 and 9.59, respectively, P<0.01). At 4 h of culture, the numbers of tubular structures of cells in 1 μmol/L 4αPDD group and 3 μmol/L 4αPDD group were significantly greater than that in PBS group (with t values of 4.68 and 4.95, respectively, P<0.05 or <0.01). At 8 h of culture, the numbers of tubular structures of cells in 1 μmol/L 4αPDD and 3 μmol/L 4αPDD groups were similar to that in PBS group (P>0.05). At 24 h of culture, compared with those in PBS group, the protein expression level of E-cadherin of cells in 3 μmol/L 4αPDD group was significantly decreased (t=5.13, P<0.01), whereas there was no statistically significant difference in the protein expression level of E-cadherin of cells in 1 μmol/L 4αPDD group (P>0.05); the protein expression level of N-cadherin of cells in 3 μmol/L 4αPDD group was significantly increased (t=4.93, P<0.01), whereas there was no statistically significant difference in the protein expression level of N-cadherin of cells in 1 μmol/L 4αPDD group (P>0.05); the protein expression levels of Slug of cells in 1 μmol/L 4αPDD group and 3 μmol/L 4αPDD group were significantly increased (with t values of 3.85 and 6.52, respectively, P<0.05 or P<0.01); and the protein expression level of Snail of cells in 3 μmol/L 4αPDD group was significantly increased (t=4.08, P<0.05), whereas there was no statistically significant difference in the protein expression level of Snail of cells in 1 μmol/L 4αPDD group (P>0.05). There were no statistically significant differences in the protein expression levels of E-cadherin, N-cadherin, Slug, or Snail of cells between 1 μmol/L 4αPDD group and 3 μmol/L 4αPDD group (P>0.05). The general condition of flaps of rats in the three groups was good on PSD 0. On PSD 1, the flaps of rats in the three groups were basically similar, with bruising and swelling at the distal end. On PSD 4, the swelling of flaps of rats in the three groups subsided, and the distal end turned dark brown and necrosis occurred, with the area of necrosis in flaps of rats in normal saline group being larger than the areas in 4αPDD group and delayed flap group. On PSD 7, the necrotic areas of flaps of rats in the 3 groups were fairly stable, with the area of necrosis at the distal end of flap of rats in delayed flap group being the smallest. On PSD 7, the flap survival rates of rats in 4αPDD group ((80±13)%) and delayed flap group ((87±9)%) were similar (P>0.05), and both were significantly higher than (70±11)% in normal saline group (with t values of 2.24 and 3.65, respectively, P<0.05 or P<0.01). On PSD 1, the overall blood perfusion signals of rats in the 3 groups were basically the same, and the blood perfusion signals in the choke vessel zone were relatively strong, with a certain degree of underperfusion at the distal end. On PSD 4, the boundary between the surviving and necrotic areas of flaps of rats in the 3 groups became evident, and the blood perfusion signals in the choke vessel zone were improved, with the normal saline group's distal hypoperfused area of flap being larger than the areas in delayed flap group and 4αPDD group. On PSD 7, the blood perfusion signals of overall flap of rats had generally stabilized in the 3 groups, with the intensity of blood perfusion signal in the choke vessel zone and overall flap of rats in delayed flap group and 4αPDD group being significantly greater than that in normal saline group. On PSD 7, the microvascular density in the choke vessel zone of flap of rats in 4αPDD group and delayed flap group were similar (P>0.05), and both were significantly higher than that in normal saline group (with t values of 4.11 and 5.38, respectively, P<0.01). Conclusions: After activation, TRPV4 may promote the migration and tubular formation of human vascular endothelial cells via the EndMT pathway, leading to the enhanced blood perfusion of perforator flap and microvascular density in the choke vessel zone, and therefore increase the flap survival rate.

[Clinical application of expanded internal mammary artery perforator flap combined with vascular supercharge in reconstruction of faciocervical scar]

Objective: To summarize the clinical experience of expanded internal mammary artery perforator (IMAP) flap combined with vascular supercharge in reconstruction of faciocervical scar. Methods: The retrospective observational study was conducted. From September 2012 to May 2021, 23 patients with postburn or posttraumatic faciocervical scars who met the inclusion criteria were admitted to Shanghai Ninth People's Hospital of Shanghai Jiao Tong University School of Medicine, including 18 males and 5 females, aged from 11 to 58 years, all of whom were reconstructed with expanded IMAP flaps. At the first stage, one or two skin and soft tissue expander (s) with appropriate rated capacity were implanted in the anterior chest area according to the location and size of the scars. The IMAP, thoracic branch of supraclavicular artery, and lateral thoracic artery were preserved during the operation. The skin and soft tissue expanders were inflated with normal saline after the operation. The flaps were transferred during the second stage. The dominant IMAP was determined preoperatively using color Doppler ultrasound (CDU) blood flow detector. The faciocervical scars were removed, forming wounds with areas of 9 cm×7 cm-28 cm×12 cm, and the perforators of superficial temporal artery and vein or facial artery and vein were preserved during the operation. The flaps were designed according to the area and size of the wounds after scar resection with the dominant IMAP as the pedicle. Single-pedicle IMAP flaps were used to repair small and medium-sized wounds. For larger defects, the blood perfusion areas of vessels in the anterior chest were evaluated by indocyanine green angiography (ICGA). In situations where the IMAP was insufficient to nourish the entire flap, double-pedicle flaps were designed by using the thoracic branch of supraclavicular artery or lateral thoracic artery for supercharging. Pedicled or free flap transfer was selected according to the distance between the donor areas and recipient areas. After transplantation of flaps, ICGA was conducted again to evaluate blood perfusion of the flaps. The donor sites of flaps were all closed by suturing directly. Statistics were recorded, including the number, rated capacity, normal saline injection volume, and expansion period of skin and soft tissue expanders, the location of the dominant IMAP, the total number of the flaps used, the number of flaps with different types of vascular pedicles, the flap area, the flap survival after the second stage surgery, the occurrence of common complications in the donor and recipient areas, and the condition of follow-up. Results: Totally 25 skin and soft tissue expanders were used in this group of patients, with rated capacity of 200-500 mL, normal saline injection volume of 855-2 055 mL, and expansion period of 4-16 months. The dominant IMAP was detected in the second intercostal space (20 sides) or the third intercostal space (5 sides) before surgery. A total of 25 expanded flaps were excised, including 2 pedicled IMAP flaps, 11 free IMAP flaps, 4 pedicled thoracic branch of supraclavicular artery+free IMAP flaps, and 8 free IMAP+lateral thoracic artery flaps, with flap areas of 10 cm×8 cm-30 cm×14 cm. After the second stage surgery, tip necrosis of flaps in three patients occurred, which healed after routine dressing changes; one patient developed arterial embolism and local torsion on the vascular pedicle at the anastomosis of IMAP and facial artery, and the blood supply recovered after thrombectomy and vascular re-anastomosis. Fourteen patients underwent flap thinning surgery in 1 month to 6 months after the second stage surgery. The follow-up for 4 months to 9 years showed that all patients had improved appearances of flaps and functions of face and neck and linear scar in the donor sites of flaps, and one female patient had obvious nipple displacement and bilateral breast asymmetry. Conclusions: The expanded IMAP flap is matched in color and texture with that of the face and neck, and its incision causes little damage to the chest donor sites. When combined with vascular supercharge, a double-pedicle flap can be designed flexibly to further enhance the blood supply and expand the flap incision area, which is a good choice for reconstruction of large faciocervical scar.

[Molluscicidal effect of 25% wettable powder of pyriclobenzuron sulphate in hilly schistosomiasis-endemic regions]

OBJECTIVE

To evaluate the molluscicidal effect of 25% wettable powder of pyriclobenzuron sulphate (WPPS) against Oncomelania snails in hilly schistosomiasis-endemic regions and test its toxicity to fish.

METHODS

In October 2020, a snail-infested setting which had been cleared was selected in Nanjian County, Yunnan Province and divided into several blocks, and the natural snail mortality was estimated. 25% WPPS was prepared into solutions at concentrations of 1 and 2 g/L, and 25% wettable powder of niclosamide ethanolamine salt (WPNES) was prepared into solutions at a concentration of 2 g/L. The different concentrations of drugs were sprayed evenly, and the same amount of water was used as blank control. Snails were surveyed using the systematic sampling method 1, 3 and 7 days post-treatment, and snail survival was observed. A fish pond was selected in Nanjian County, and 2 kg 25% WPPS was evenly sprayed on the water surface to allow the effective concentration of 20 g/L. Fish mortality was estimated 8, 24, 48 and 72 h post-treatment.

RESULTS

One-day treatment with 1 and 2 g/L WPPS and 2 g/L WPNES resulted in 97.99%, 97.99% and 94.11% adjusted snail mortality rates (χ² = 3.509 and 3.509, both P values > 0.05), and the adjusted snail mortality was all 100% 3 d post-treatment with 1 and 2 g/L WPPS and 2 g/L WPNES, while 7-day treatment with 1 and 2 g/L WPPS and 2 g/L WPNES resulted in 91.75%, 86.57% and 57.76% adjusted snail mortality rates (χ² = 14.893 and 42.284, both P values < 0.05). Treatment with 2 g/L WPPS for 72 h resulted in a 0.67% cumulative mortality rate of fish.

CONCLUSIONS

25% WPPS is effective for snail control and highly safe for fish, which is feasible for use in hilly schistosomiasis-endemic regions.

[Diagnostic value of FCGR1B gene transcription level in active tuberculosis]

Objective: To investigate the diagnostic potential of Fc fragment of IgG receptor 1b gene (FCGR1B) transcription level in active tuberculosis. Methods: From February to September of 2018, we collected peripheral blood from patients with active tuberculosis, latent tuberculosis infection (LTBI), cured patients with tuberculosis, healthy people and patients with pneumonia in the Eighth Medical Center of PLA General Hospital. Peripheral blood mononuclear cells (PBMCs) were isolated for total RNA extraction and cDNA synthesis. The expression of FCGR1B mRNA in PBMCs was detected by quantitative real-time PCR (QPCR). Nonparametric test was used to compare the differential expression of FCGR1B mRNA between patients with active tuberculosis and control groups, and the relationships between FCGR1B mRNA expression and patient's illness condition and inflammatory indexes were analyzed by Correlation analysis. The potential of FCGR1B mRNA as a diagnostic marker for active tuberculosis was evaluated by receiver operating characteristic curve (ROC) analysis. Results: The expression of FCGR1B mRNA in PBMCs from patients with active tuberculosis was significantly increased when compared with non-tuberculosis controls, including individuals with LTBI, healthy people, cured patients with tuberculosis and patients with pneumonia (u=2 081, P<0.001). The expression of FCGR1B mRNA was higher in patients with tuberculosis who had more bacteria(H=12.35, P=0.015), and was correlated with the C-reactive protein (CRP) (r=0.30, P=0.008). ROC analysis showed that FCGR1B mRNA could distinguish active tuberculosis from non-tuberculosis with area under curve (AUC) of 0.849. The sensitivity and specificity were 71.43% and 84.17% respectively. The AUC of FCGR1B mRNA in distinguishing extra-pulmonary tuberculosis from controls was 0.906. The sensitivity and specificity were 84.62% and 91.89%, respectively. Conclusion: FCGR1B mRNA is a potential molecular marker for diagnosis of active tuberculosis.

[Progress in immunologic and genetic research of chronic obstructive pulmonary disease with lung cancer]

Chronic obstructive pulmonary disease (COPD) and lung cancer are two of the respiratory diseases with the highest mortality, which have posed huge threat to human health and brought great burden to society and family. The mechanism of COPD with lung cancer is very complicated. In order to clarify the linkage between these two diseases, this review summarized the present researches of COPD and lung cancer from the aspects of immunology and genetics. The immunologic aspect focused on innate immune of neutrophil and macrophage, adaptive immune of B cell, T cell and oxidative stress. The genetic aspect focused on susceptibility gene and microRNA. Through the thorough elaboration of these researches, we hope to provide useful insights into the further research of mechanism, diagnosis and targeted therapy of COPD with lung cancer.

[Epidemiological characteristics of imported COVID-19 cases in Beijing]

Objective: To analyze the epidemiological characteristics of imported COVID-19 cases and the effect of vaccination on virus load and disease severity of the cases in Beijing. Methods: The data of the imported COVID-19 cases in Beijing were collected from the National Notifiable Infectious Disease Reporting System of China Information for Disease Control and Prevention and Epidemiology investigation. The data were processed and analyzed by Excel 2010 and SPSS 22.0. Results: From June 1 to September 30, 2021, a total of 171 imported COVID-19 cases were reported in Beijing, of which 66.67% (114/171) were asymptomatic. The cases were mainly from the Philippines, the United Arab Emirates, the United Kingdom and the Russian Federation, accounting for 67.84% (116/171). The male to female ratio of the cases was 2∶1 (114∶57). The median age M (Q₁, Q₃) of the cases was 28 (23, 36) years. The cases of Chinese accounted for 80.12% (137/171). The sequencing of the whole genome of the virus in 47 imported COVID-19 cases showed that the proportion of Delta variant was 76.60% (36/47). The COVID-19 vaccination coverage rate in the cases was 60.82% (104/171), but the full vaccination coverage rate was 53.80% (92/171). In the imported COVID-19 cases, 13.53% (23/170) were screened to be SARS-CoV-2 nucleic acid positive on the day when they arrived in Beijing, and all the cases were positive for 2019-nCoV nucleic acid within 28 days. The severity of the disease was higher in the unvaccinated group than in the partially vaccinated group and fully vaccinated group (P<0.001). In the unvaccinated group, there were 1 severe case and 1 critical case. The median Ct values M (Q₁, Q₃) of N gene and ORFlab gene in unvaccinated group were 32.51 (23.23, 36.06) and 32.78 (24.00, 36.38), respectively. There was no significant difference in the median of double-gene Ct value between the partially vaccinated group and the fully vaccinated group. Conclusions: During the study period, most of the imported COVID-19 cases in Beijing were asymptomatic. No matter vaccinated or not, the viral loads in the COVID-19 cases were similar, but the vaccination could reduce the severity of the disease.

COVID-19 prevention measures reduce dengue spread in Yunnan Province, China, but do not reduce established outbreak

The COVID-19 pandemic and measures against it provided a unique opportunity to understand the transmission of other infectious diseases and to evaluate the efficacy of COVID-19 prevention measures on them. Here we show a dengue epidemic in Yunnan, China, during the pandemic of COVID-19 was dramatically reduced compared to non-pandemic years and, importantly, spread was confined to only one city, Ruili. Three key features characterized this dengue outbreak: (i) the urban-to-suburban spread was efficiently blocked; (ii) the scale of epidemic in urban region was less affected; (iii) co-circulation of multiple strains was attenuated. These results suggested that countermeasures taken during COVID-19 pandemic are efficient to prevent dengue transmission between cities and from urban to suburban, as well to reduce the co-circulation of multiple serotypes or genotypes. Nevertheless, as revealed by the spatial analysis, once the dengue outbreak was established, its distribution was very stable and resistant to measures against COVID-19, implying the possibility to develop a precise prediction method.

[Performance of loop-mediated isothermal amplification (LAMP) assay for detection of Schistosoma japonicum infection in Oncomelania snails in schistosomiasis transmission-interrupted regions]

OBJECTIVE

To compare the effectiveness of loop-mediated isothermal amplification (LAMP) assay and microscopic examinations for detection of Schistosoma japonicum infections in Oncomelania hupensis in transmission-interrupted regions, so as to provide insights into the optimization of snail surveillance tools in these regions.

METHODS

Four hilly schistosomiasis-endemic villages where transmission interruption was achieved were selected in Heqing County of Yunnan Province as the study villages, including Xinzhuang and Gule villages in hilly regions and Lianyi and Yitou villages in dam regions. Snail survey was performed by means of systematic sampling combined with environmental sampling in July 2018. All captured snails were identified for S. japonicum infections using microscopy. In addition, 10 to 20 snails were randomly sampled from each snail habitat following microscopy, numbered according to environments and subjected to LAMP assay. The positive rate of settings with S. japonicum-infected snails was compared among villages.

RESULTS

A total of 7 949 living snails were captured from 83 snail habitats in 4 villages, and no S. japonicum infection was detected in snails. There were 226 mixed samples containing 1 786 snails subjected to LAMP assay, and positive LAMP assay was found in 3 mixed samples from 3 snail habitats in 2 dam villages. The positive rates of settings with S. japonicum-infected snails were comparable between Lianyi Village (one setting) and Yitou Village (2 set tings) (5.89% vs. 14.29%, P = 0.344). However, the overall positive rate of settings with S. japonicum-infected snails was significantly higher in dam villages (9.67%, 3/31) than in hilly villages (0) (P = 0.048).

CONCLUSIONS

LAMP assay is more sensitive to detect S. japonicum infections in O. hupensis than conventional microcopy method, which may serve as a supplementary method for detection of S. japonicum infections in O. hupensis in high-risk snail habitats in hilly transmission-interrupted regions.

[Lymphoplasmacytic lymphoma: a clinicopathological and prognostic analysis of 27 cases]

Objective: To study the clinical manifestations, pathologic features, diagnosis and differential diagnosis, treatment and prognosis of lymphoplasmacytic lymphoma/Waldenström's macroglobulinemia (LPL/WM). Methods: Twenty-seven cases of LPL from January 2016 to December 2020 at Guangdong Provincial People's Hospital were collected. The clinical data, histomorphology, immunophenotype, MYD88 L265P mutation, treatment and prognosis were analyzed retrospectively. Results: There were 19 males and 8 female patients, with median age of 63 years. The most common initial symptoms were fatigue related to anemia. Bone marrow was involved in all cases, lymphadenopathy was seen in 11 cases and splenomegaly in 10 cases. Monoclonal IgM type protein was detected in 25 cases, meeting the diagnostic criteria of WM. Microscopically, bone marrow and lymph nodes were infiltrated by small lymphocytes, plasmacytoid lymphocytes or plasma cells. The cells expressed pan B-cell markers and showed immunoglobulin light chain restriction. There was no expression of CD5, and low expression of CD23 and CD10; Ki-67 index was usually low. The positive rate of MYD88 L265P mutation was 73.9% (17/23). Most of the patients were treated with rituximab combined with alkylating agents, nucleoside analogues or immunomodulators, and the few patients with relapse or progression were treated with Ibutinib. During the 3-168 months' follow-up period, recurrence or progression were seen in nine cases. Thrombocytopenia, elevated β2-microglobulin and high-risk group were associated with recurrence or progression of the disease (P<0.05). The overall survival (OS) and progression-free survival (PFS) of the high-risk patients were significantly lower than those of the low-medium risk patients (P<0.05). Conclusions: LPL/WM is an exclusive diagnosis; the detection of MYD88 L265P mutation has high diagnostic value, but it is not specific. These cases should be assessed comprehensively for their clinical manifestation, serum IgM protein level and immunophenotype. The overall prognosis of LPL/WM is good, but there are still a small number of high-risk patients with rapid progress, and so the symptomatic patients should be diagnosed accurately and treated in a timely manner.

[Analysis of occurrence and treatment of perioperative complete atrioventricular block by transcatheter aortic valve implantation]

Objective: To retrospectively analyze the occurrence and treatment of perioperative complete atrioventricular block (CAVB) by transcatheter aortic valve implantation (TAVI). Methods: A total of 65 patients who underwent TAVI via femoral artery in the Heart Center of Henan People's Hospital from October 2017 to May 2021 were enrolled. Perioperative data of patients were recorded. The patients were divided into two groups according to whether complete atrioventricular block was occurred during TAVI: complete atrioventricular block group (Group CAVB) and non-complete atrioventricular block group (Group NCAVB). Multivariate logistic regression model was used to analyze the risk factors of complete atrioventricular block during transcatheter aortic valve implantation. The incidence of perioperative complications were recorded. Results: The patients age was (69.1±7.3) years old. and there were 35 males and 30 femals. There were 15 patients in group CAVB with complete atrioventricular block and 50 patients in group NCAVB. Multivariate analysis showed that preoperative right bundle branch block [OR (95%CI) vs 3.325 (2.132-13.061), P=0.005] and severe aortic valve calcification [OR (95%CI) vs 1.271 (1.052-3.326), P=0.030] were independent correlative factors for CAVB during TAVI perioperative period. The implantation rate of permanent pacemaker in group CAVB was 73.3% (11 cases), which was higher than 6.0% (3 cases) in group NCAVB (P<0.001). Conclusions: It indicated that preoperative right bundle branch block and severe aortic valve calcification are correlative factors for complete atrioventricular block for TAVI. The implantation rate of permanent pacemaker in complete atrioventricular block group increased significantly.

[Development of a fluorescent recombinase-aided isothermal amplification-based nucleic acid assay for detection of Leishmania]

OBJECTIVE

To develop a fluorescent recombinase-aided isothermal amplification (RAA)-based nucleic acid assay for detection of Leshimania.

METHODS

Specific primers and probes were designed targeting Leishmania internal transcribed spacer 1 (ITS1) gene for RAA assay, and a fluorescent RAA assay was developed for detection of Leishmania following screening of primer pairs and optimization of primer and probe concentrations. The sensitivity of RAA assay for detection of Leishmania was evaluated using recombinant plasmid containing Leishmania ITS1 gene sequences at different copies and Leshimania genomic DNA at different concentrations as templates, and the specificity of RAA assay for detection of Leishmania was evaluated using the genomic DNA of transfusion-transmitted parasites, including Babesia microti, Toxoplasma gondii, Plamodium vivax, P. ovale, P. falciparum, P. malariae, L. donovani and L. infantum.

RESULTS

After the optimal primer pair was screened from 9 pairs of primer combinations, the final primer and probe concentrations were optimized as 0.3 μmol/L and 0.08 μmol/L, respectively. Nucleic acid detection of Leishmania was completed by the fluorescent RAA assay at an isothermal temperature of 39 °C within 20 min. Remarkable florescent signals were seen within 5 min following RAA detection of genomic DNA of L. donovani and L. infantum, and no cross-reactions were observed with B. microti, T. gondii, P. vivax, P. ovale, P. falciparum or P. malariae. The lowest limitation of detection of the fluorescent RAA assay was 10 copies/μL recombinant plasmid containing Leishmania ITS1 gene sequences and 1 fg/μL Leishmania genomic DNA.

CONCLUSIONS

A rapid, simple, sensitive and specific fluorescent RAA assay is successfully developed for detection of L. donovani and L. infantum, which is effective for field screening of leishmaniasis.

[Establishment of a fluorescent recombinase-aided isothermal amplification assay for nucleic acid detection of Paraginiumus skrjabini and preliminary evaluation of its detection efficiency]

OBJECTIVE

To establish a nucleic acid assay for detection of Paragonimus skrjabini based on the recombinase-aided isothermal amplification (RAA) technique, and to preliminarily evaluate its detection efficiency.

METHODS

The metacercariae of P. skrjabini, P. westermani and Euparagonimus cenocopiosus were isolated from crabs, and genomic DNA was extracted for molecular characterization. The cytochrome coxidase 1 (cox1) gene sequence of P. skrjabini was selected as the target gene fragment, and the primers and probes were designed, screened and synthesized for RAA assay. The genomic DNA of P. skrjabini metacercariae from Jiyuan City and Yiyang County of Luoyang City, Henan Province were used as templates for verification of the fluorescent RAA assay. The fluorescent RAA assay was performed to detect different concentrations of plasmids containing target gene fragment and P. skrjabini metacercariae genomic DNA to determine the sensitivity. Fluorescent RAA assay was performed with recombinant plasmids containing P. skrjabini cox1 gene sequences at different concentrations and P. skrjabini genomic DNA as templates to evaluate its sensitivity, and the genomic DNA of P. westermani, E. cenocopiosus, Clonorchis sinensis and Schistosoma japonicum was detected with fluorescent RAA assay to evaluate its specificity.

RESULTS

P. skrjabini, P. westermani and E. cenocopiosus metacercariae were isolated from crabs, respectively. Molecular characterization and phylogenetic analysis confirmed their homology with the genes sequences of standard Paragonimus strains in GenBank. A fluorescent RAA assay was successfully established for nucleic acid detection of P. skrjabini, and the genomic DNA of P. skrjabini metacercariae from Jiyuan City and Yiyang County of Luoyang City, Henan Province was amplified using the fluorescent RAA assay within 5 min, while the negative control was not amplified. If the recombinant plasmid containing P. skrjabini cox1 gene sequences was used as templates, the fluorescent RAA assay showed the lowest detection limit of 10 copies/μL, and positive amplification was observed within 5 min. If genomic DNA was used as templates, the fluorescent RAA assay showed the lowest detection limit of 10 pg/μL, and all positive amplifications were found within 5 to 10 min. In addition, the fluorescent RAA assay was tested negative for P. westermani, E. cenocopiosus, C. sinensis and S. japonicum.

CONCLUSIONS

A rapid, sensitive and specific fluorescent RAA assay is successfully established for nucleic acid detection of P. skrjabini, which has potential values in rapid field detection and species identification in freshwater crabs in areas endemic for P. skrjabini.

High MEK/ERK signalling is a key regulator of diapause maintenance in the cotton bollworm, Helicoverpa armigera

MEK/ERK signalling has been identified as a key factor that terminates diapause in Sarcophaga crassipalpis and Bombyx mori. Paradoxically, high p-MEK/p-ERK signalling induces diapause in pupae of the moth Helicoverpa armigera; however, the regulatory mechanism is unknown. In the present study, we show that p-MEK and p-ERK are elevated in the brain of diapause-destined pupae and suppression of MEK/ERK activity terminates diapause progress. Reactive oxygen species (ROS) activate MEK/ERK signalling, causing large-scale phosphorylation of downstream proteins. The levels of ubiquitin-conjugated proteins are also significantly reduced when ROS or p-ERK level decreased. Moreover, terminated diapause progress by 20-hydroxyecdysone injection significantly decreases p-MEK, p-ERK and phospho-ribosomal S6 kinase levels, while phospho-MAPK substrates and ubiquitin-conjugated protein levels increase. Our data demonstrate that high MEK/ERK signalling mediated by ROS promotes diapause maintenance via increasing phosphorylation and degradation of downstream substrates. The results of this study may provide important information for understanding the regulatory mechanisms during insect diapause.