Leucine supplementation alleviates immune and antioxidant function damage in adult rats induced by early weaning

BACKGROUND

Early weaning (EW) can lead to stress and destroy intestinal integrity. Leucine has functional diversity in antioxidant, immune, and metabolic regulation.

OBJECTIVE

This study aims to explore a lifelong impact of early weaning on intestinal, immune and antioxidant functions of adult rats and the role of leucine supplementation in the alleviation of the damage caused by early weaning.

METHODS

In this 211-day study, 36 SD rat pups were divided into three groups: 21-day weaning normal group (C), 17-day early weaning group (E) and 17-day early weaning group with two-month leucine supplementation (EL). The content of amino acids in serum, immune and antioxidant indexes, intestinal morphology, liver transcriptomics, mRNA, and protein expression of signaling pathway were determined.

RESULTS

EW reduced the protein expression level of sIgA and GSH in jejunum, and increased the protein expression levels of IgA, IgM, and IL-17 in serum, and TNFα and IL-1β in jejunum. The impairment by EW was activated via NF-κB signal pathway. In terms of antioxidation, EW reduced the level of GSH in jejunum. After leucine supplementation, the damage induced by EW was partially repaired.

CONCLUSIONS

EW causes long-term damage to the intestinal barrier function, immunity, apoptosis factor, and antioxidant function of rats and leucine supplementation could alleviate the impairment, suggesting possible approach to EW.

Age-dependent mechanical properties of tail tendons in wild-type and mimecan gene-knockout mice - A preliminary study

Mimecan, or osteoglycin, belongs to the family of small leucine-rich proteoglycans. In connective tissues mimecan is implicated in the development and maintenance of normal collagen fibrillar organization. Since collagen fibrils are responsible for tissue reinforcement, the absence of mimecan could lead to abnormal tissue mechanical properties. Here, we carried out a preliminary investigation of possible changes in the mechanical properties of tendons in mice lacking a functional mimecan gene, as a function of age. Tail tendons were dissected from mimecan gene knockout (KO) and wild type (WT) mice at ages 1, 4 and 8 months and mechanical properties evaluated using a microtensile testing equipment. Mimecan gene knockout resulted in changes in tendon elasticity- and fracture-related properties. While tendons of WT mice exhibited enhanced mechanical properties with increasing age, this trend was notably attenuated in mimecan KO tendons, with the exception of fracture strain. When genotype and age were considered as cross factors, the diminution in the mechanical properties of mimecan KO tendons was significant for yield strength, modulus and fracture strength. This effect appeared to affect the mice at 4 month old. These preliminary results suggest that mimecan may have a role in regulating age-dependent mechanical function in mouse tail tendon.

Solvent-Free Nonthermal Destruction of PFAS Chemicals and PFAS in Sediment by Piezoelectric Ball Milling

Studies on the destruction of solid per- and polyfluoroalkyl substances (PFAS) chemicals and PFAS-laden solid wastes significantly lag behind the urgent social demand. There is a great need to develop novel treatment processes that can destroy nonaqueous PFAS at ambient temperatures and pressures. In this study, we develop a piezoelectric-material-assisted ball milling (PZM-BM) process built on the principle that ball collisions during milling can activate PZMs to generate ∼kV potentials for PFAS destruction in the absence of solvents. Using boron nitride (BN), a typical PZM, as an example, we successfully demonstrate the complete destruction and near-quantitative (∼100%) defluorination of solid PFOS and perfluorooctanoic acid (PFOA) after a 2 h treatment. This process was also used to treat PFAS-contaminated sediment. Approximately 80% of 21 targeted PFAS were destroyed after 6 h of treatment. The reaction mechanisms were determined to be a combination of piezo-electrochemical oxidation of PFAS and fluorination of BN. The PZM-BM process demonstrates many potential advantages, as the degradation of diverse PFAS is independent of functional group and chain configurations and does not require caustic chemicals, heating, or pressurization. This pioneering study lays the groundwork for optimizing PZM-BM to treat various PFAS-laden solid wastes.

Association between acrylamide exposure and sex hormones among premenopausal and postmenopausal women: NHANES, 2013-2016

PURPOSE

Acrylamide (AA) is a potential carcinogen that mainly comes from fried, baked and roasted foods, and Hb adducts of AA (HbAA) and its metabolite glycidamide (HbGA) are the biomarkers of its exposure. Increasing evidence suggests that AA is associated with various hormone-related cancers. This study aims to explore the association of HbAA and HbGA with female serum sex hormone concentrations.

METHODS

942 women from the National Health and Nutrition Examination Survey cycles (2013-2016) were included in this cross-sectional study. The associations between HbAA or HbGA or HbGA/HbAA and sex hormones were assessed by the multiple linear regression. Further stratified analyses were conducted to figure out the effects of menopausal status, BMI and smoking status on sex hormone levels.

RESULTS

Among all participants, 597 were premenopausal and 345 were postmenopausal. HbAA was positively associated with both two androgen indicators. Specifically, a ln-unit increase in HbAA was associated with 0.41 ng/dL higher ln(total testosterone, TT) (95% CI 0.00, 0.27) and 0.14 ng/dL higher ln(free testosterone) (95%CI 0.00, 0.28), respectively. However, HbGA concentrations had no association with sex hormones in the overall population. Additionally, HbGA/HbAA was negatively associated with TT and SHBG in the overall population as well as postmenopausal women. In stratified analysis, higher HbAA was associated with rising TT in postmenopausal women (β = 0.29, 95%CI 0.04, 0.53) and underweight/normal-weight women (β = 0.18, 95%CI 0.03, 0.33). Other indicators had no significant association detected in estradiol and sex hormone-binding globulin.

CONCLUSION

Our results revealed that HbAA was positively associated with androgen concentrations, especially in postmenopausal and BMI < 25 women.

[Prevalence of unhealthy lifestyle among children and adolescents of Han nationality in China]

Objective: To explore the epidemiological characteristics and geographical distribution of unhealthy lifestyle among children and adolescents of Han nationality in China and obtain evidence for proposing the related strategies to improve the well-being of this population. Methods: Students aged 6-22 years old were selected from the Chinese National Survey on Students Constitution and Health in 2019. The prevalence of unhealthy lifestyles (physical inactivity, lack of outdoor activity, sedentary behavior, excessive screen time, sleep insufficiency, unhealthy eating behavior) between sex, residence, and age groups was calculated and compared. Multilevel logistic regression was used to explore the influencing factors of unhealthy lifestyle. Results: The prevalence of moderate-to-vigorous physical activity less than 1 h/d or 30 min/d were 82.06% and 54.69%, respectively. The prevalence of less than 2 h/d or 3 h/d of outdoor activities were 95.20% and 83.26%, respectively. The prevalence of more than 2 h/d or 3 h/d of sitting time were 50.64% and 31.92%, respectively. The prevalence of more than 2 h/d or 3 h/d of screen time were 42.02% and 27.79%, respectively. The prevalence of sleep insufficiency, excessive sugary beverages consumption (≥ 1 time/d), and insufficient consumption of eggs, milk, and breakfast (<7 d/week) were 66.49%, 20.97%, 83.36%, 70.71%, and 34.34%, respectively. The prevalence of severe sleep insufficiency, excessive sugary beverages consumption (≥ 3 times/d), and insufficient consumption of eggs, milk, and breakfast (≤2 d/week) were 27.77%, 8.21%, 47.21%, 32.36% and 9.73%, respectively. Conclusion: In 2019, unhealthy lifestyle is common among Han students aged 6-22 years in China. It is of importance to propose policies to strengthen the health education and initiatives to support healthy behaviors in Han children and adolescents. Jointly promotion on the creation of a healthy environment for Han children and adolescents, and formulation of targeted improvement measures in accordance with the epidemic characteristics in various regions are essential to improve the healthy lifestyle of this population.

Lycopene Affects Intestinal Barrier Function and the Gut Microbiota in Weaned Piglets via Antioxidant Signaling Regulation

BACKGROUND

In pig production, early and abrupt weaning frequently causes weaning stress, which manifests as oxidative damage, barrier disruption, and digestion and absorption capacity declines. Lycopene exhibits beneficial antioxidant capacity in both humans and other animal models.

OBJECTIVES

The present study aimed to investigate the effects of lycopene supplementation on early weaning stress in piglets and the underlying mechanisms by examining the oxidative stress state, gut intestinal barrier function, and the gut microbiota.

METHODS

Twenty-four 21-day-old weaned piglets [Duroc × (Landrace × Yorkshire); castrated males; 5.48 ± 0.10 kg initial body weight] were randomly assigned to 2 treatments. The piglets were fed a basal diet (control treatment) or a basal diet supplemented with 50 mg/kg lycopene (lycopene treatment) for 28 days. The serum lipid levels, serum and jejunum enzyme activities, jejunum morphology, mRNA and protein expression, and gut microbiota were determined.

RESULTS

Compared with the control treatment, lycopene supplementation increased the serum catalase activity (P = 0.042; 62.0%); serum total cholesterol concentration (P = 0.020; 14.1%); and jejunum superoxide dismutase activity (P = 0.032; 21.4%), whereas it decreased serum (P = 0.039, 23.0%) and jejunum (P = 0.047; 20.9%) hydrogen peroxide concentrations. Additionally, lycopene increased the mRNA and protein expression of NFE2-like bZIP transcription factor 2 (214.0% and 102.4%, respectively) and CD36 (100.8% and 145.2%, respectively) in the jejunum, whereas it decreased the mRNA and protein expression of Kelch-like ECH-associated protein 1 (55.6% and 39.8%, respectively ). Lycopene also improved jejunal morphology, increasing the villus height (P = 0.018; 27.5%) and villus:crypt ratio (P < 0.001; 57.9%). Furthermore, it increased the abundances of potentially beneficial bacterial groups, including Phascolarctobacterium and Parasutterella, and decreased those of potentially pathogenic bacterial groups, including Treponema_2 and Prevotellaceae_unclassified.

CONCLUSIONS

Lycopene supplementation strengthens the intestinal barrier function and improves the gut microbiota in weaned piglets by regulating intestinal antioxidant signaling.

[Associations between early onset of puberty and obesity types in children: Based on both the cross-sectional study and cohort study]

OBJECTIVE

To explore and analyze the relationship between early onset of puberty and different types of obesity in children, by combining large sample cross-sectional survey data with long-term longitudinal cohort data, so as to provide clues for further clarifying the health hazards of early onset of puberty and obesity prevention and control.

METHODS

The research data were from the cross-sectional survey data of seven provinces(autonomous regions, municipalities) in China and the cohort data of adolescent development in Xiamen. The study first found the association between early onset of puberty and obesity by Logistic regression on the cross-sectional data, and then used Poisson regression to analyze the association between early puberty initiation and various types of obesity risk.

RESULTS

In the study, 43 137 and 1 266 children were included in the cross-sectional survey and cohort survey respectively. The cross-sectional study found that among the girls aged 10-13 years, compared with the girls of the same age who did not start puberty, the body mass index (BMI)-Z score of the girls in the puberty start group was 0.5-0.8 higher, and the waist circumference Z score was 0.4-0.7 higher, and the risk of various types of obesity was higher. At the same time, the early onset of puberty was positively correlated with simple obesity, central obesity and compound obesity, the OR (95%CI) were 1.86 (1.42-2.44), 1.95 (1.65-2.32) and 1.86 (1.41-2.45), respectively. No significant association was found in boys. According to the cohort data, in girls, the risk of simple obesity was 6.00 times [RR (95%CI): 6.00 (1.07-33.60)], the risk of central obesity was 3.30 times [RR (95%CI): 3.30 (1.22-8.92)], and the risk of compound obesity was 5.76 times [RR (95%CI): 5.76 (1.03-32.30)], compared with the group without early puberty initiation, while no association between early puberty initiation and obesity was found in boys.

CONCLUSION

Based on the cross-sectional survey and longitudinal cohort survey, it is confirmed that the early onset of puberty in girls may increase the risk of simple obesity, central obesity and compound obesity, while there is no significant correlation between puberty onset and obesity in boys.

Quantifying Radiation Belt Electron Loss Processes at L < 4

We present a comprehensive analysis of the processes that lead to quasilinear pitch-angle-scattering loss of electrons from the L < 4 region of the Earth's inner magnetosphere during geomagnetically quiet times. We consider scattering via Coulomb collisions, hiss waves, lightning-generated whistler (LGW) waves, waves from ground-based very-low-frequency (VLF) transmitters, and electromagnetic ion cyclotron (EMIC) waves. The amplitude, frequency, and wave normal angle spectra of these waves are parameterized with empirical wave models, which are then used to compute pitch-angle diffusion coefficients. From these coefficients, we estimate the decay timescales, or lifetimes, of 30 keV to 4 MeV electrons and compare the results with timescales obtained from in-situ observations. We demonstrate good quantitative agreement between the two over most of the L and energy range under investigation. Our analysis suggests that the electron decay timescales are very sensitive to the choice of plasmaspheric density model. At L < 2, where our theoretical lifetimes do not agree well with the observations, we show that including Coulomb energy drag (ionization energy loss) in our calculations significantly improves the quantitative agreement with the observed decay timescales. We also use an accurate model of the geomagnetic field to provide an estimate of the effect that the drift-loss cone has on the theoretically calculated electron lifetimes, which are usually obtained using an axisymmetric dipole field.

Effect of Gardenia Pomace Supplementation on Growth Performance, Blood Metabolites, Immune and Antioxidant Indices, and Meat Quality in Xiangcun Pigs

To investigate the effect of gardenia pomace (GP) as an unconventional feed of antioxidants, 180 Xiangcun pigs were randomly divided into 3 groups during the finishing period, with 6 replicates per group and 10 pigs per replicate. During the 47-day feeding period, the pigs were fed either a control diet based on corn and soybean meal (control group), or the control diet added with 50 g/kg or 100 g/kg GP (groups GP5 and GP10, respectively). Feed and water were provided ad libitum. One pig per replicate was slaughtered and sampled. The effects on growth performance, meat quality, digestibility, metabolism, and immunity and antioxidant properties of the pigs were investigated. The results showed that GP had no significant effect on the growth performance of Xiangcun pigs. Compared with the control group, the digestibility of crude ash, phosphorus, and crude fibre of pigs in the GP groups improved (p < 0.01), and the content of inosinic acid in the longissimus dorsi muscle increased (p < 0.05). The addition of GP to the diet significantly increased superoxide dismutase (SOD) levels in the liver and spleen, and glutathione peroxidase (GSH-Px) activity in the longissimus dorsi muscle and spleen (p < 0.05). Additionally, it significantly reduced the contents of malondialdehyde (MDA) in the liver and spleen (p < 0.05). The GP5 group had a higher inosinic acid content in the longissimus dorsi and lower levels of the inflammatory factor interleukin-2 and interleukin-8 than those in the other groups (p < 0.05). The GP10 group had a higher IgA level (p < 0.05). Adding different proportions of GP to the diet improved the a* and b* of the longissimus dorsi muscles of Xiangcun pigs (p < 0.05). In summary, GP, as an unconventional feed, improved the apparent digestibility of the diet and body antioxidant capacity in Xiangcun pigs during the finishing period and did not negatively affect the growth performance or meat quality.

Threonine supplementation prevents the development of fat deposition in mice fed a high-fat diet

Obesity is the main factor involved in the onset of many diseases. Threonine supplementation has been demonstrated to reduce fat mass and serum triglycerides in already obese mice. However, it is unclear whether threonine could inhibit the development of obesity in mice without previous high-fat diet induction. In the present study, mice were fed a chow diet (CD) or a high-fat diet (HFD), supplemented or not with threonine (3.0% in drinking water) for 15 weeks. Results showed that mice subjected to chronic threonine supplementation showed decreased body weight, epididymal white adipose tissue weight, serum low-density lipoprotein cholesterol, and total cholesterol in comparison with HFD-fed mice. In the epididymal adipose tissue, gene expressions of sterol regulatory element-binding protein 1c and fatty acid synthase were up-regulated, while hormone sensitive lipase, adiponectin and fibroblast growth factor 21 were down-regulated. In the liver tissue, gene expressions of sirtuin1, adenosine monophosphate-activated protein kinase and peroxisome proliferator activated receptor γ co-activator 1α were up-regulated by threonine supplementation in HFD-fed mice. These results suggest that long-term threonine supplementation inhibited fat mass and improved lipid metabolism, making it a potential agent to prevent the development of diet-induced obesity.

LncRNA HOTTIP PROMOTES OVARIAN CANCER CELL INVASION AND METASTASIS BY STABILIZING HIF-1α IN THE ANOXIC CELLULAR MICROENVIRONMENT

Background

The high recurrence rate and low survival rate of ovarian cancer (OC) patients are closely related to an anoxic environment. We aim to study the mechanism of long non-coding RNA (lncRNA) HOXA transcript at the distal tip (HOTTIP) on hypoxia ovarian cancer cells (OCC) and its mechanism was investigated.

Methods

Knockdown and overexpression of HOTTIP in human OCC (SKOV-3, OVCAR3) were performed. The expression levels of HOTTIP and HIF-1α were monitored by qRT-PCR and WB. Transwell was conducted to validate the cell migration and invasion. ELISA was performed to calculate VEGF concentration in cells. Cell viability was monitored by CCK-8. Cell apoptosis and cycle were tested by flow cytometry. RNA pull-down was used to analyze the interaction between HIF-1α and HOTTIP.

Results

HOTTIP was highly expressed in OCC. After HOTTIP knockdown, HIF-1α expression and VEGF concentration in OCC were decreased. Cell migration, invasion, and cell viability were decreased. Cell apoptosis rate and G0/G1 phase cells were increased. RNA pull-down indicated a direct interaction between HIF-1α and HOTTIP.

Conclusions

HOTTIP formed a positive feedback loop with HIF-1α to promote the development and metastasis of hypoxia ovarian cancer. This study provided theoretical support for the development of new OC treatment strategies.

[Clinical characteristics and whole exome sequencing results of patients with Möbius syndrome]

Objective: To analyze the clinical characteristics of patients with Möbius syndrome (MBS) and to explore likely pathogenic genes. Methods: Cross-sectional study. The study enrolled 18 sporadic MBS patients who visited the Eye Center of Beijing Tongren Hospital Affiliated to Capital Medical University from July 2018 to December 2021. All patients completed the general information questionnaire and underwent detailed ophthalmic examinations and general physical examinations. Seventeen patients received MRI examination of cranial nerves and the orbit. The peripheral venous blood of all patients and their nuclear family members was collected, the genomic DNA was extracted, and the pathogenic gene variations that may lead to MBS were identified by whole exome sequencing and bioinformatics analysis. Results: Among the 18 patients, there were 8 males and 10 females, and the age was (4.5±4.0) years (range, 8 months to 17 years). All patients showed congenital, bilateral or unilateral abduction deficit and facial weakness, which met the minimum diagnostic criteria of MBS. Among them, bilateral abduction deficit (16/18) and bilateral facial weakness (15/18) were more common. Nine patients were orthotopic in primary position, eight presented with esotropia, and one showed hypotropia. All patients had ametropia, of which 4 patients were diagnosed as amblyopia. Fifteen patients were also accompanied by other multiple congenital malformations, mainly characterized by abnormal development of glossopharynx (14/18) and limbs (5/18), and 7 patients were also accompanied by motor retardation. In addition, 9 patients had intrauterine exposure to adverse factors. Among the 17 patients who underwent MRI, 15 patients had bilateral hypoplasia of the abducens nerve, two had unilateral hypoplasia of the abducens nerve, 14 showed bilateral hypoplasia of the facial nerve, and three showed hypoplasia of the left facial nerve. Besides, some patients were also accompanied by hypoplasia of other cranial nerves, mainly the glossopharyngeal nerve and the hypoglossal nerve. No definite pathogenic variations were found by whole exome sequencing and bioinformatics analysis. Conclusions: The main clinical features of MBS were congenital abduction deficit and facial weakness, with complicated manifestations and variable severity. MRI showed absence or thinning of the abducens nerve and the facial nerve. The results of MRI can be used as a supplement to the diagnostic criteria of MBS. The mutation detection rate of MBS was low, and half of patients had exposure to adverse factors during pregnancy, suggesting that there was a multifactorial pathogenic mechanism in MBS.

Active Precipitation of Radiation Belt Electrons Using Rocket Exhaust Driven Amplification (REDA) of Man-Made Whistlers

Ground-based very low frequency (VLF) transmitters located around the world generate signals that leak through the bottom side of the ionosphere in the form of whistler mode waves. Wave and particle measurements on satellites have observed that these man-made VLF waves can be strong enough to scatter trapped energetic electrons into low pitch angle orbits, causing loss by absorption in the lower atmosphere. This precipitation loss process is greatly enhanced by intentional amplification of the whistler waves using a newly discovered process called rocket exhaust driven amplification (REDA). Satellite measurements of REDA have shown between 30 and 50 dB intensification of VLF waves in space using a 60 s burn of the 150 g/s thruster on the Cygnus satellite that services the International Space Station. This controlled amplification process is adequate to deplete the energetic particle population on the affected field lines in a few minutes rather than the multi-day period it would take naturally. Numerical simulations of the pitch angle diffusion for radiation belt particles use the UCLA quasi-linear Fokker Planck model to assess the impact of REDA on radiation belt remediation of newly injected energetic electrons. The simulated precipitation fluxes of energetic electrons are applied to models of D-region electron density and bremsstrahlung X-rays for predictions of the modified environment that can be observed with satellite and ground-based sensors.

[Epidemic status of imported malaria before and after malaria elimination in Jiaozuo City of Henan Province]

OBJECTIVE

To analyze and compare the epidemiological characteristics of imported malaria in Jiaozuo City before and after malaria elimination, so as to provide insights into the malaria surveillance during the post-elimination stage and prevention of re-establishment of imported malaria.

METHODS

Data pertaining to the epidemic situation and individual investigation of malaria in Jiaozuo City before (from 2010 to 2016) and after malaria elimination (from 2017 to November, 2020) were captured from the National Notifiable Disease Reporting System and the Information System for Parasitic Diseases Control and Prevention of Chinese Center for Disease Control and Prevention and were analyzed statistically.

RESULTS

A total of 74 imported malaria cases were reported in Jiaozuo City from 2010 to 2021. Imported cases were predominantly Plasmodium falciparum malaria cases in Jiaozuo City before and after malaria elimination, and there was no significant difference in the proportion of malaria parasite species (χ² = 0.234, P > 0.05). The imported malaria cases was predominantly reported in Wuzhi County, and was identified in overseas male farmers and businessmen at ages of 20 to 59 years, while the greatest number of imported malaria cases was reported in June and December before and after malaria elimination. The imported malaria cases predominantly acquired malaria parasite infections in sub-Saharan African countries; however, the proportion of imported malaria cases returning from Southeast Asian counties increased after malaria elimination than before malaria elimination (χ² = 5.989, P < 0.05). The longest duration from onset to definitive diagnosis of malaria reduced from 27 days before malaria elimination to 18 days after malaria elimination, and the median duration reduced from 3 days to 2 days, while the proportion of definitive diagnosis of malaria increased from 60.47% before malaria elimination to 83.87% after malaria elimination (χ² = 4.724, P < 0.05). In addition, the proportion of malaria cases definitively diagnosed and reported by medical institutions increased after malaria elimination than before malaria elimination (χ² = 5.406, P < 0.05).

CONCLUSIONS

The imported malaria patients were predominantly P. falciparum malaria cases in Jiaozuo City during 2010 to 2021, and the patient's medical care-seeking awareness and medical staff's diagnosis and treatment ability have improved after malaria elimination. It is necessary to strengthen and improve malaria surveillance and response system and prevent the re-establishment of overseas imported malaria.

[Clinical characteristics and outcomes of myasthenia gravis patients with double positive antibodies against acetylcholine receptor and muscle-specific tyrosine kinase]

Objective: To investigate the clinical manifestations, treatment characteristics and outcomes of myasthenia gravis (MG) dually positive for anti-acetylcholine receptor antibody (AChR-Ab) and anti-muscle-specific tyrosine kinase antibody (MuSK-Ab). Method: MG patients hospitalized in the First Affiliated Hospital of Sun Yat-sen University from August 2017 to November 2020 were retrospectively collected. Thirty-four MuSK-Ab positive MG (MuSK-MG) patients, 11 double-antibodies positive MG (DP-MG) patients, and 80 AChR-Ab positive MG (AChR-MG) patients were included and allocated to three different groups. The clinical data of patients in the three groups were collected, and the differences of demographic characteristics, clinical manifestations and treatment outcomes between DP-MG patients and AChR-MG and MuSK-MG patients were analyzed. Result: The proportion of female and male patients in DP-MG group was 7/11 and 4/11 respectively, and the onset age of DP-MG was (41±27) years.The difference in gender distribution between DP-MG and AChR-MG groups was statistically significant (P<0.05). The proportion of extraocular muscle involvement in the DP-MG and MuSK-MG groups (8/11 and 52.9%) was lower than that in the AChR-MG group (83.8%), and the difference was statistically significant (P<0.05). The incidence of myasthenia crisis in DP-MG and MuSK-MG groups (54.5% and 61.8%) were higher than that in AChR-MG group (20.0%), with astatistically significant difference(P<0.05). The positive rate of neostigmine test in DP-MG and MuSK-MG groups(8/11 and 74.2%) were lower than that of AChR-MG group (96.8%), and the positive rate of low frequency repetitive nerve stimulation (RNS) in DP-MG group (5/10) was lower than that in AChR-MG group (85.1%), with statistically significant differences (all P<0.05). MuSK-Ab titer was positively correlated with the course of disease (r=0.466, P<0.05), and antibody titer decreased after symptom improvement (P<0.05). The response of patients in DP-MG and MuSK-MG groups to cholinesterase inhibitors (2/11 and 9.1%) was worse than that in the AChR-MG group (66.3%), and the incidence of side effects in the two groups (5/11 and 39.4%) was higher than that in the AChR-MG group (15.0%), with statistically significant differences (all P<0.05). There were 4 DP-MG patients underwent thymectomy, and the pathological results detected two cases of thymoma and two cases of thymic hyperplasia. Subsequent follow-up showed that 5 (5/11) DP-MG patients achieved minimal manifestation status or better status. Conclusion: The gender distribution, age of onset, pharmacological characteristics and electrophysiological examination of DP-MG patients were similar to those of MuSK-MG patients, but the severity of DP-MG patients was between that of AChR-MG and MuSK-MG patients.

Public attitudes and influencing factors toward COVID-19 vaccination for adolescents/children: a scoping review

OBJECTIVE

This study aimed to systematically clarify attitudes and influencing factors of the public toward COVID-19 vaccination for children or adolescents.

STUDY DESIGN

This was a scoping review.

METHODS

This scoping review screened, included, sorted, and analyzed relevant studies on COVID-19 vaccination for children or adolescents before December 31, 2021, in databases, including PubMed, Elsevier, Web of Science, Cochrane Library, and Wiley.

RESULTS

A total of 34 studies were included. The results showed that the public's acceptance rate toward COVID-19 vaccination for children or adolescents ranged from 4.9% (southeast Nigerian mothers) to 91% (Brazilian parents). Parents' or adolescents' age, gender, education level, and cognition and behavior characteristics for the vaccines were the central factors affecting vaccination. The vaccine's safety, effectiveness, and potential side-effects were the main reasons affecting vaccination.

CONCLUSIONS

Realizing current public attitudes of COVID-19 vaccination for adolescents or children can effectively develop intervention measures and control the pandemic as soon as possible through herd immunity.

Molecular cloning and yeast two-hybrid provide new evidence for unique sporophytic self-incompatibility system of Corylus

The Corylus genus contains several important nut producing species and exhibits sporophytic self-incompatibility (SSI). However, the underlying molecular mechanisms of SSI in Corylus remain largely unknown. To clarify whether Corylus and Brassica share the same SSI molecular mechanism. We cloned ChaTHL1/2, ChaMLPK, ChaARC1, ChaEX70A1 genes from Ping'ou hybrid hazelnut using RACE techniques and tested the interaction between the ChaARC1 and ChaSRK1/2. We also examined the pistil-pollen interactions using scanning electron microscopy. We found no differences in the stigma surface within 1 h after compatible or incompatible pollination. Compatible pollen tubes penetrated the stigma surface, while incompatible pollen did not penetrate the stigma 4 h after pollination. Bioinformatics analysis revealed that ChaTHL1/2, ChaMLPK, ChaARC1 and ChaEX70A1 have corresponding functional domains. Quantitative real-time PCR (qRT-PCR) analysis showed that ChaTHL1/2, ChaMLPK, ChaARC1 and ChaEX70A1 were not regularly expressed in compatible or incompatible pollination. Furthermore, the expression patterns of ARC1, THL1/2, MLPK and Exo70A1 were quite distinct between Corylus and Brassica. According to yeast two-hybrid assays, ChaSRK1/2 did not interact with ChaARC1, confirming that the SRK-ARC1 signalling pathway implicated in the SSI response of Brassica was not conserved in Corylus. These results further reinforce the conclusion that, notwithstanding the similarity of the genetic basis, the SSI mechanism of Corylus does not conform in many respects with that of Brassica. Our findings could be helpful to better explore the potential mechanism of SSI system in Corylus.

[Assessment of biological activities of exopolysaccharides with different relative molecular masses extracted from Rhizopus nigricans]

OBJECTIVE

To evaluate the antioxidant, anti-tumor and immunomodulatory activities of exopolysaccharides with different molecular masses isolated from Rhizopus nigricans.

METHODS

Three polysaccharides with different molecular masses, namely RPS-1, RPS-2 and RPS-3, were separated from the fermentation broth of Rhizopus nigricans by fractional ethanol precipitation, and their capacity for scavenging DPPH, ABTS, and hydroxyl radicals was assessed. Cell counting kit-8 was used to analyze the changes in the viability of MFC, A549 and RAW 264.7 cells following treatments with the 3 polysaccharides; The level of nitric oxide in the supernatant of RAW 264.7 cells was detected using a nitric oxide detection kit, and the apoptosis rate of A549 cells was analyzed with flow cytometry.

RESULTS

All the 3 polysaccharides had good antioxidant activities, and among them RPS-1 with a medium molecular mass exhibited the strongest scavenging capacity for DPPH and ABTS radicals (P < 0.05) while RPS-3 with the lowest molecular mass had the best scavenging activity for hydroxyl radicals (P < 0.01). All the 3 polysaccharides were capable of inhibiting the proliferation of MFC cells and A549 cells, activating the macrophages RAW 264.7 cells, and inducing apoptosis of A549 cells. RPS-2 with the highest molecular mass showed the strongest inhibitory effects against MFC and A549 cells (P > 0.05), and RPS-2 had the strongest activity for inducing apoptosis in A549 cells (P < 0.05). Compared with the other two polysaccharides, RPS-2 more strongly promoted the proliferation of RAW 264.7 cells and enhanced NO release from the cells (P < 0.05).

CONCLUSION

The 3 polysaccharides all have antioxidant, anti-tumor and immunomodulatory activities, and among them RPS-1 and RPS-3 have better antioxidant activities, and RPS-2 has stronger anti-tumor and immunomodulatory activities.