[Effects of unsafe sexual behavior and sexual orientation on previous HIV testing and HIV testing willingness among college students in Harbin]

Objective: To analyze the effects of unsafe sexual behavior and sexual orientation on previous HIV testing and HIV testing willingness among college students in Harbin, to provide a theoretical basis for promoting and promoting HIV testing among them. Methods: A cross-sectional survey design was used to place the automatic vending machine of HIV urine test kit in 9 universities in Harbin from December 2017 to January 2018. The questionnaire star was used to design and recruit college students to carry out an anonymous online survey. The estimated sample size was 6 659. A multivariate logistic regression model was used to analyze the effects of unsafe sexual behavior and sexual orientation on previous HIV testing and HIV testing willingness among college students. WPS 2016 was used to sort out the database, and SPSS 21.0 software was used for statistical analysis. Results: A total of 60 849 valid questionnaires were collected. 19.1% (11 189/58 605) of college students reported having sex. College students who used condoms correctly every time, occasionally or never during sex in the past six months 58.5% (6 206/10 603), 25.2%(2 669/10 603)and 16.3% (1 728/10 603), respectively. Heterosexuality, homosexuality and bisexuality accounted for 94.1% (54 393/57 823), 2.4% (1 369/57 823) and 3.5% (2 061/57 823), respectively. The HIV testing willingness of college students was 73.3% (44 572/60 849). The proportion of previous HIV testing was 10.3% (951/9 241). Results of the multivariate logistic analysis showed that compared with the college students who used condoms correctly whenever they had sex in the past six months, there was no significant difference in the proportion of previous HIV testing among college students who sometimes/occasionally used or never used condoms (OR=0.94,95%CI:0.69-1.29; OR=1.11,95%CI:0.73-1.67), but their willingness to HIV testing was lower (OR=0.79, 95%CI:0.71-0.89; OR=0.48, 95%CI:0.42-0.55); Compared with heterosexual college students, homosexual or bisexual college students have a higher proportion of previous HIV testing (OR=2.62, 95%CI:1.62-4.24; OR=2.04, 95%CI:1.25-3.32), but have lower HIV testing willingness (OR=0.76, 95%CI: 0.62-0.93; OR=0.64, 95%CI: 0.53-0.77). Conclusions: Unsafe sexual behavior existed among college students in Harbin, and college students with weak awareness of HIV prevention also have weak awareness of testing. Behavioral intervention should be strengthened and HIV testing promoted. Compared with heterosexuals, homosexual or bisexual college students had a higher proportion of previous HIV testing, but their willingness to test was lower. The HIV detection mode with better concealment, accuracy, and convenience should be promoted on the college's campus.

A high precision phase measurement system implemented in FPGA with phase interpolator

High precision timing distribution is crucial to many large scale cosmology and particle physics experiments. Besides the space and energy information, the accurate timing provides an extra dimension for physics event reconstruction. In the timing distribution system, accurate clock phase measurement is an indispensable tool to monitor the phase drift and to achieve accurate phase adjustment. This paper introduces a novel phase measurement method implemented in the Xilinx Field Programmable Gate Array (FPGA). It uses the dedicated phase interpolator in the multi-gigabit transceiver. A design based on this method is implemented within the Kintex Ultrascale series FPGA. The preliminary test result shows that a sub-picosecond level precision is achieved. With this system, the nonlinearity of the phase adjustment in the Xilinx transceiver is measured.

Severe Adaptive Immune Suppression May Be Why Patients With Severe COVID-19 Cannot Be Discharged From the ICU Even After Negative Viral Tests

During the COVID-19 pandemic, a phenomenon emerged in which some patients with severe disease were critically ill and could not be discharged from the ICU even though they exhibited negative viral tests. To explore the underlying mechanism, we collected blood samples from these patients and analyzed the gene expression profiles of peripheral immune cells. We found that all enrolled patients, regardless of changes in genes related to different symptoms and inflammatory responses, showed universally and severely decreased expression of adaptive immunity-related genes, especially those related to T/B cell arms and HLA molecules, and that these patients exhibited long-term secondary infections. In addition, no significant change was found in the expression of classic immunosuppression molecules including PD-1, PD-L1, and CTLA-4, suggesting that the adaptive immune suppression may not be due to the change of these genes. According to the published literatures and our data, this adaptive immunosuppression is likely to be caused by the "dysregulated host response" to severe infection, similar to the immunosuppression that exists in other severely infected patients with sepsis.

Discovery and Nanosized Preparations of (S,R)-Tylophorine Malate as Novel anti-SARS-CoV-2 Agents

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has stimulated the search for effective drugs for its prevention and treatment. Natural products are an important source for new drug discovery. Here, we report that, NK007(S,R), a tylophorine malate, displays high antiviral activity against SARS-CoV-2 with an EC₅₀ 0.03 μM in vitro, which is substantially lower than that of remdesivir (EC₅₀: 0.8 μM in vitro), the only authorized drug to date. The histopathological research revealed that NK007(S,R) (5 mg/kg/dose) displayed a protection effect in lung injury induced by SARS-CoV-2, which is better than remdesivir (25 mg/kg/dose). We also prepared two nanosized preparations of NK007(S,R), which also showed good efficacy (EC₅₀: NP-NK007, 0.007 μM in vitro; LP-NK007, 0.014 μM in vitro). Our findings suggest that tylophora alkaloids, isolated from the traditional Chinese medicine Cynanchum komarovii AL, offer a new skeleton for the development of anticoronavirus drug candidate.

[Epidemiological characteristics of COVID-19 outbreak in Gaocheng district of Shijiazhuan]

Objective: To describe the epidemiological characteristics of COVID-19 outbreak in Gaocheng district of Shijiazhuan. Methods: Data and epidemiological survey reports of COVID-19 cases in the outbreak were collected from China's Infectious Disease Information System, Shijazhuang Municipal Center for Diseases Prevention and Control and official information published by the National Health Commission of China. The data were analyzed, using the descriptive epidemiological method. Results: From January 2^nd to February 14^th, 2021, a total of 1 033 laboratory confirmed COVID-19 cases were reported in Shijiazhuang. The attack rate was 9.36/100 000. The cases were distributed in 14 counties, and most cases (859/1 033, 83.16%) were reported in Gaocheng, and the disease spread to 5 provinces. The cases in Xiaoguo village (299 cases), Liujiazhuo village (107 cases) and Nanqiaozhai village (162 cases) of Zengcun township in Gaocheng accounted for 54.99% of the total cases in Shijiazhuang. The attack rates in the villages mentioned above were 7 412.00/100 000, 10 348.16/100 000 and 6 612.24/100 000, respectively. The ratio of urban cases to rural cases was 1∶15.53. The male to female ratio of the cases was 1∶1.34. The average age of the cases was 40.49 years. The incidence peaks occurred on January 3^rd (9.97%, 103 cases) and on January 9^th (9.10%, 94 cases). A total of 307 clusters occurred, in which 228(74.27%) occurred in households and 48 (15.64%) occurred in schools or child care settings. But the clusters related with church ceremony had the highest case numbers (82.67 cases/time), followed by wedding feast or feast celebrating the first month of newborn (28.29 cases/time). About 33.02% (313/948) of symptomatic cases only visited the village doctors or private clinics and had no medical care seeking history before the outbreak. Conclusions: The COVID-19 epidemic in Gaocheng of Shijiazhuang was a typical one in rural area. The rapid and hiding transmission of the outbreak was mainly due to the poor health service seeking of the rural residents and the frequent mass gathering.

A bivalent recombinant vaccine targeting the S1 protein induces neutralizing antibodies against both SARS-CoV-2 variants and wild-type of the virus

The emerging variants of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in pandemic call for the urgent development of universal corona virus disease 2019 (COVID-19) vaccines which could be effective for both wild-type SARS-CoV-2 and mutant strains. In the current study, we formulated protein subunit vaccines with AS03 adjuvant and recombinant proteins of S1 subunit of SARS-CoV-2 (S1-WT) and S1 variant (K417N, E484K, N501Y, and D614G) subunit (S1-Mut), and immunized transgenic mice that express human angiotensin-converting enzyme 2 (hACE2). The S1 protein-specific antibody production and the neutralization capability for SARS-CoV-2 and B.1.351 variant were measured after immunization in mice. The results revealed that the S1-Mut antigens were more effective in inhibiting the receptor-binding domain and ACE2 binding in B.1.351 variant than in wild-type SARS-CoV-2. Furthermore, the development of a bivalent vaccine exhibited the ideal neutralization properties against wild-type and B.1.351 variant, as well as other variants. Our findings may provide a rationale for the development of a bivalent recombinant vaccine targeting the S1 protein that can induce the neutralizing antibodies against both SARS-CoV-2 variants and wild-type of the virus and may be of importance to explore the potential clinical use of bivalent recombinant vaccine in the future.

Phageome-based vaccination and human innate immune modulation could be a useful strategy to control human Coronavirus infections

Human Coronavirus (CoV) infections, including SARS-COV, MERS-COV, and SARS-CoV-2, usually cause fatal lower and upper respiratory tract infections due to exacerbated expression of pro-inflammatory cytokines and chemokines. We aim to summarize different aspects, such as CoV immune evasion mechanisms and host innate immune response to these infections, and their role in pathogenesis. We have also elaborated the up-to-date findings on different vaccine development strategies and progress against CoVs in both humans and non-human models. Most importantly, we have described the Phageome-human immune interaction, its therapeutic usage as anti-viral, anti-inflammatory agent, and implications for multiple vaccine development systems. The data suggest that endogenous phages might play a vital role in eliminating the infection and regulating the body's immune system. Considering the innate-immune-induced pathogenesis against CoVs and the therapeutic aptitude of phageome, we propose that the prophylactic administration of phages and phage-based vaccines could be a useful strategy to control the emerging CoV infections.

R13 preserves motor performance in SOD1G93A mice by improving mitochondrial function

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by death of motor neurons in the brain and spinal cord. However, so far, there is no effective treatment for ALS.

Methods: In this study, R13, a prodrug of 7,8-dihydroxyflavone, selectively activating tyrosine kinase receptor B (TrkB) signaling pathway, was administered prophylactically to 40-day old SOD1^G93A mice for 90 days. The motor performance was investigated by rotarod test, climbing-pole test, grip strength test and hanging endurance test. Afterwards, the spinal cord and medulla oblongata of 130-day old mice were harvested, and the proteomics revealed the effect of R13 on mouse protein expression profile. Astrocytes and microglial proliferation were assessed by immunohistochemical analysis. The number of motor neurons in the spinal cord is determined by Nissl staining. The effect of R13 on gastrocnemius morphology was assessed by HE staining. The effect of R13 on the survival rate was accomplished with worms stably expressing G93A SOD1.

Results: Behavioral tests showed that R13 significantly attenuated abnormal motor performance of SOD1^G93A mice. R13 reduced the advance of spinal motor neuron pathology and gastrocnemius muscle atrophy. The proliferation of microglia and astrocytes was reduced by R13 treatment. Mitochondriomics analysis revealed that R13 modified the mitochondrial protein expression profiles in the medulla oblongata and spinal cord of SOD1^G93A mice, particularly promoting the expression of proteins related to oxidative phosphorylation (OXPHOS). Further study found that R13 activated AMPK/PGC-1α/Nrf1/Tfam, promoted mitochondrial biogenesis and ameliorated mitochondrial dysfunction. Lastly, R13 prolonged the survival rate of worms stably expressing G93A SOD1.

Conclusions: These findings suggest oral R13 treatment slowed the advance of motor system disease in a reliable animal model of ALS, supporting that R13 might be useful for treating ALS.

The investigation of mRNA vaccines formulated in liposomes administrated in multiple routes against SARS-CoV-2

COVID-19 pandemic has resulted in an unprecedented global public health crisis. It is obvious that SARS-CoV-2 vaccine is needed to control the global COVID-19 public health crisis. Since obvious advantages including fast manufacturing speed, potent immunogenicity and good safety profile, six mRNA vaccines have been used to prevent SARS-CoV-2 infections in clinic with lipid nanoparticles (LNP) formulation via intramuscular injection. In this work, we first constructed RBD-encoding mRNA (RBD-mRNA) formulated in liposomes (LPX/RBD-mRNA) and investigated the influence of administration routes on the immunogenicity. LPX/RBD-mRNA can express RBD in vivo and successfully induced SARS-CoV-2 RBD specific antibodies in the vaccinated mice, which efficiently neutralized SARS-CoV-2 pseudotyped virus. Moreover, the administration routes were found to affect the virus neutralizing capacity of sera derived from the immunized mice and the types (Th1-type and Th2-type) of cellular immune responses. This study indicated that liposome-based RBD-mRNA vaccine with optimal administration route might be a potential candidate against SARS-CoV-2 infection with good efficacy and safety.

[Study on the mechanism of resistance to cypermethrin in Culex pipiens pallens using proteomics]

OBJECTIVE

To compare the differentially expressed proteins between cypermethrin-resistant and -sensitive Culex pipiens pallens, so as to unravel the mechanism underlying the resistance to cypermethrin in Cx. p. pallens.

METHODS

A quantitative proteomic analysis was performed among cypermethrin-sensitive and -resistant isolates of Cx. p. pallens using isobaric tags for relative and absolute quantification (iTRAQ) labeling coupled with liquid chromatography with tandem mass spectrometry (LC-MS/MS).

RESULTS

A total of 164 differentially expressed proteins were identified between cypermethrin-sensitive and -resistant isolates of Cx. p. pallens, including 54 up-regulated proteins and 110 down-regulated proteins. A large number of cuticular proteins, larval cuticular proteins, pupal cuticular proteins and cuticular structural constituent proteins, which are associated with cytoskeletal structure and components, were differentially expressed between cypermethrin-sensitive and -resistant isolates of Cx. p. pallens. Thirteen proteins, which were involved in energy production and conversion, translation, ribosomal structure and biogenesis, lipid transport and metabolism, post-translational modification, protein turnover, chaperones, cytoskeleton and intracellular transportation, were validated to be differentially expressed between cypermethrin-sensitive and -resistant isolates of Cx. p. pallens, which may serve as potential markers of cypermethrin resistance.

CONCLUSIONS

Multiple insecticide resistance mechanisms contribute to the resistance to cypermethrin in Cx. p. pallens, including cuticular resistance and metabolic resistance, and the cuticular protein genes and cytochrome P450 enzymes may play an important role in the resistance of Cx. p. pallens to cypermethrin.

Interferon Regulatory Factor 5 siRNA-Loaded Folate-Modified Cationic Liposomes for Acute Lung Injury Therapy

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is an overwhelming pulmonary inflammation with limited clinical treatment strategies. Interferon regulatory factor 5 (IRF5) is a crucial regulator of inflammation factors, which can be upregulated under an inflammatory state and related to the efferocytosis of macrophages. Herein, IRF5 was knockdown by small interfering RNA (siIRF5) to promote the anti-inflammatory effect of macrophages. Macrophage-targeting cationic liposome modified by folate (FA-LP) was developed to deliver siIRF5 (FA-LP/siIRF5). Liposomes were characterized for their particle size, zeta potential, protein adsorption and hemolysis of red blood cells. The amount of IRF5 mRNA and the expression of IRF5 were measured using quantitative reverse transcription PCR (RT-qPCR) and western blot, respectively. The phenotype and efferocytosis of macrophages and the regulatory pathway of efferocytosis and biodistribution of liposomes in the ALI mice model were investigated. Data revealed that FA-LP/siIRF5 could obviously downregulate the expression of IRF5 in macrophages, skewing the polarization of macrophages to M2 phenotype (anti-inflammatory state) and thus improving their efferocytosis. Moreover, regulation of efferocytosis of macrophages by siIRF5 is related to the NF- B pathway. The in vivo biodistribution of FA-LP exhibited higher accumulation in the inflammatory lungs, suggesting that FA-LP could be considered as a promising gene delivery system and FA-LP/siIRF5 is an alternative strategy for the treatment of ALI/ARDS. To the best of our knowledge, this is the first study reporting that siIRF5 can be used for the treatment of ALI/ARDS.

Association of disease condition with changes in intestinal flora, and plasma endotoxin and vascular endothelial growth factor levels in patients with liver cancer

OBJECTIVE

Currently, the therapeutic effect on patients with liver cancer is associated with disease development. Meanwhile, the efficacy in patients with advanced liver cancer is far from satisfactory. Therefore, the aim of this study was to explore the association of disease condition with changes in liver function indexes, intestinal flora, and plasma endotoxin (ET) and vascular endothelial growth factor (VEGF) levels in patients with liver cancer.

PATIENTS AND METHODS

A total of 300 patients with primary liver cancer in our hospital were enrolled in this study. All patients were divided into three groups, including early liver cancer group, middle liver cancer group, and advanced liver cancer group. Peripheral blood was collected from each subject to detect liver function indexes, procalcitonin (PCT), plasma ET, and VEGF levels. Furthermore, mid-posterior-segment stools were collected from 15 cases in each group, and sent to the company for detection of intestinal flora.

RESULTS

Liver function indexes in peripheral blood of patients with liver cancer changed with the changes in disease condition. With the progression of liver cancer, the level of aspartate aminotransferase (AST) increased significantly, and the highest was observed in advanced liver cancer patients [(91.18±10.34) U/L] (p=0.046). However, the level of plasma total protein declined significantly, which was (24.83±1.75) g/L in advanced liver cancer patients (p=0.035). The changes in total bilirubin were significantly associated with the progression of liver cancer (p=0.003). The abundance of Clostridiales, Firmicutes, and Streptococcus in the intestinal tract was high in early liver cancer group. The abundance of Ruminococcaceae, Pasteurellaceae, Tanticharoenia, and Vagococcus in the intestinal tract was high in middle liver cancer group. Meanwhile, the abundance of Bifidobacteriales, Actinobacteria, Barnesiella, Porphyromonadaceae, and Pseudomonadales in the intestinal tract was high in advanced liver cancer group. In patients with liver cancer, the level of Enterobacteriaceae was positively correlated with that of Firmicutes (r=0.36, p=0.003), whereas it was negatively correlated with Lactobacillus (r=-0.72, p=0.021). The level of Lactobacillus was positively correlated with that of Ruminococcaceae (r=0.39, p=0.043), whereas it was negatively correlated with that of Firmicutes (r=-0.27, p=0.019). In addition, the level of PCT markedly rose in advanced liver cancer group [(6.89±0.35) ng/mL] (p=0.021). The level of ET increased significantly with the development of liver cancer, with the highest level observed in advanced liver cancer group [(0.71±0.09) EU/mL] (p=0.004). The level of VEGF also increased remarkably with the aggravation of liver cancer, and the highest was found in advanced liver cancer group [(112.33±2.11) μmol/L], showing differences among groups (p<0.05).

CONCLUSIONS

With the progression of liver cancer, the abundance of Barnesiella, etc., rose and that of Ruminococcaceae, etc., declined in the intestinal tract. Meanwhile, the composition of intestinal flora was changed, and the levels of plasma ET and VEGF increased.

Do distribution and expansion of exotic invasive Asteraceae plants relate to leaf construction cost in a man-made wetland?

Exotic species especially Asteraceae plants severely invade wetlands in Shenzhen Bay, an important part of the coast wetland in Guangdong-Hong Kong-Macau Bay Area, China. However, the reasons causing their expansion are unclear. The leaf traits and expansion indices of six invasive Asteraceae plants from the Overseas Chinese Town (OCT) wetland were studied and the results showed that nearly 45% of the total plant species (31 out of 69 species) in the OCT wetland, belonging to 15 families and 27 genera, were exotic invasive species. The expansion indices of six Asteraceae species negatively correlated with their leaf construction cost based on mass (CCM), caloric values and carbon concentration, but their relations with ash content were positive. Multiple linear regression analysis revealed that CCM was the most important factor affecting the expansion of an exotic species, indicating CCM may be an important reason causing the expansion of exotic species in coastal wetlands.