Caught in the Crossfire: Fears of Chinese-American Scientists

The US leadership in science and technology has greatly benefitted from immigrants from other countries, most notably from China in the recent decades. However, feeling the pressure of potential federal investigation since the 2018 launch of the China Initiative under the Trump administration, Chinese-origin scientists in the US now face higher incentives to leave the US and lower incentives to apply for federal grants. Analyzing data pertaining to institutional affiliations of more than 2.3 million scientific papers, we find a steady increase in the return migration of Chinese-origin scientists from the US back to China. We also conducted a survey of Chinese-origin scientists employed by US universities in tenure or tenure-track positions (n=1300), with results revealing general feelings of fear and anxiety that lead them to consider leaving the US and/or stop applying for federal grants.Comment: 16 pages, 2 figure

The Redox-Sensing Regulator Rex Contributes to the Virulence and Oxidative Stress Response of Streptococcus suis Serotype 2

Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen responsible for septicemia and meningitis. The redox-sensing regulator Rex has been reported to play critical roles in the metabolism regulation, oxidative stress response, and virulence of various pathogens. In this study, we identified and characterized a Rex ortholog in the SS2 virulent strain SS2-1 that is involved in bacterial pathogenicity and stress environment susceptibility. Our data show that the Rex-knockout mutant strain Δrex exhibited impaired growth in medium with hydrogen peroxide or a low pH compared with the wildtype strain SS2-1 and the complementary strain CΔrex. In addition, Δrex showed a decreased level of survival in whole blood and in RAW264.7 macrophages. Further analyses revealed that Rex deficiency significantly attenuated bacterial virulence in an animal model. A comparative proteome analysis found that the expression levels of several proteins involved in virulence and oxidative stress were significantly different in Δrex compared with SS2-1. Electrophoretic mobility shift assays revealed that recombinant Rex specifically bound to the promoters of target genes in a manner that was modulated by NADH and NAD+. Taken together, our data suggest that Rex plays critical roles in the virulence and oxidative stress response of SS2

Green synthesis of biogenetic Te(0) nanoparticles by high tellurite tolerance fungus Mortierella sp. AB1 with antibacterial activity

Tellurite [Te(IV)] is a high-toxicity metalloid. In this study, a fungus with high Te(IV) resistance was isolated. Strain AB1 could efficiently reduce highly toxic Te(IV) to less toxic Te(0). The reduced products formed rod-shaped biogenetic Te(0) nanoparticles (Bio-TeNPs) intracellularly. Further TEM-element mapping, FTIR, and XPS analysis showed that the extracted Bio-TeNPs ranged from 100 to 500 nm and consisted of Te(0), proteins, lipids, aromatic compounds, and carbohydrates. Moreover, Bio-TeNPs exhibited excellent antibacterial ability against Shigella dysenteriae, Escherichia coli, Enterobacter sakazakii, and Salmonella typhimurium according to inhibition zone tests. Further growth and live/dead staining experiments showed that E. coli and S. typhimurium were significantly inhibited by Bio-TeNPs, and cells were broken or shriveled after treatment with Bio-TeNPs based on SEM observation. Additionally, the antioxidant and cytotoxicity tests showed that the Bio-TeNPs exhibited excellent antioxidant capacity with no cytotoxicity. All these results suggested that strain AB1 showed great potential in bioremediation and Bio-TeNPs were excellent antibacterial nanomaterials with no cytotoxicity.Peer reviewe

Clearing Persistent Extracellular Antigen of Hepatitis B Virus: An Immunomodulatory Strategy To Reverse Tolerance for an Effective Therapeutic Vaccination

Development of therapeutic vaccines/strategies to control chronic hepatitis B virus (HBV) infection (CHB) has been challenging due to HBV-induced tolerance. In this study, we explored strategies for breaking tolerance and restoring the immune response to the HBV surface antigen in tolerant mice. We demonstrated that immune tolerance status is attributed to the level and duration of circulating HBsAg in HBV carrier models. Removal of circulating HBsAg by a monoclonal anti-HBsAg antibody in tolerant mice could gradually reduce tolerance and reestablish B cell and CD4+ T cell responses to subsequent Engerix-B vaccination, producing protective IgG. Furthermore, HBsAg-specific CD8+ T cells induced by the addition of a TLR agonist, resulted in clearance of HBV in both serum and liver. Thus, generation of protective immunity can be achieved by clearing extracellular viral antigen with neutralizing antibodies followed by vaccination

Mechanical damage characteristics and nondestructive testing techniques of fruits: a review

Abstract Fruits will be subjected inevitably to various external forces in the process of harvesting, transportation, processing, and storage, which will cause mechanical damage. The research on mechanical properties and damage mechanisms of fruit can effectively control its loss. In this study, fruits are divided into different types according to their morphology and structure. The impact, vibration, static pressure, and other mechanical damage on fruits are studied. It is important to identify the damaged parts of fruit after damage quickly and accurately. Therefore, this study analyzes the application of nondestructive testing technologies such as spectral detection technology, NMR (nuclear magnetic resonance) detection technology, and acoustic and electrical characteristics detection technology in fruit damage detection

Prevalence of porcine circovirus-like agent P1 in Jiangsu, China

Recently, we identified a novel porcine circovirus type 2-like agent P1 isolate from swine. The present study represents the first survey of P1 prevalence in swine herds from Jiangsu, China, by using PCR targeting the complete genome of P1. Prevalences of 50% and 19% were found among 6 herds and 248 animals, respectively. The results indicate a high prevalence of P1 in China pig populations

Skin transcriptome profiles associated with coat color in sheep

Background Previous molecular genetic studies of physiology and pigmentation of sheep skin have focused primarily on a limited number of genes and proteins. To identify additional genes that may play important roles in coat color regulation, Illumina sequencing technology was used to catalog global gene expression profiles in skin of sheep with white versus black coat color. Results There were 90,006 and 74,533 unigenes assembled from the reads obtained from white and black sheep skin, respectively. Genes encoding for the ribosomal proteins and keratin associated proteins were most highly expressed. A total of 2,235 known genes were differentially expressed in black versus white sheep skin, with 479 genes up-regulated and 1,756 genes down-regulated. A total of 845 novel genes were differentially expressed in black versus white sheep skin, consisting of 107 genes which were up-regulated (including 2 highly expressed genes exclusively expressed in black sheep skin) and 738 genes that were down-regulated. There was also a total of 49 known coat color genes expressed in sheep skin, from which 13 genes showed higher expression in black sheep skin. Many of these up-regulated genes, such as DCT, MATP, TYR and TYRP1, are members of the components of melanosomes and their precursor ontology category. Conclusion The white and black sheep skin transcriptome profiles obtained provide a valuable resource for future research to understand the network of gene expression controlling skin physiology and melanogenesis in sheep

Multilevel unilateral versus bilateral pedicular percutaneous vertebroplasty for osteoporotic vertebral compression fractures

Study designRetrospective study.ObjectiveControversy exists over the need for unilateral vs. bilateral pedicular percutaneous vertebroplasty (PVP) for patients with osteoporotic vertebral compression fractures (OVCFs). Clinical research is scarce comparing two approaches for multi-level PVP. This study aimed at evaluating the clinical and radiographic outcomes of multi-level PVP using two approaches for OVCFs.MethodsSeventy-eight patients with OVCFs undergoing multi-level PVP were enrolled including 36 patients undergoing unilateral PVP and 42 undergoing bilateral PVP. The clinical and radiological assessments including the Visual Analogue Scale (VAS), sagittal and coronal segmental Cobb, vertebral compression ratio (VCR), and vertebral sides ratio (VSR) were evaluated preoperatively and postoperatively.ResultsAll patients achieved a minimum 2-year follow-up. A total of 164 fractured vertebrae were enrolled. Regarding clinical efficacy, the VAS score improved in both groups after surgery, but the two groups did not differ significantly. The changes tendency in Sagittal Segmental Cobb, VSR, and VCR were similar postoperatively, and no statistically significant difference between groups. As for the Coronal Segmental Cobb angle, patients in unilateral and bilateral groups were shown to have 5.0° ± 4.0° and 2.6° ± 2.2° degrees loss of correction at a minimum 2-years follow-up duration, respectively. The loss of correction in the Coronal Segmental Cobb of unilateral group was significantly greater than that of bilateral group.ConclusionBoth multi-level unilateral and bilateral pedicular PVP achieved significant pain reduction and vertebral height restoration. Moreover, the bilateral PVP has shown advantages in stabilizing Coronal Cobb angle in patients with OVCFs

Efficacy and safety of stem cell therapy in cerebral palsy: A systematic review and meta-analysis

Aim: Although the efficacy and safety of stem cell therapy for cerebral palsy has been demonstrated in previous studies, the number of studies is limited and the treatment protocols of these studies lack consistency. Therefore, we included all relevant studies to date to explore factors that might influence the effectiveness of treatment based on the determination of safety and efficacy.Methods: The data source includes PubMed/Medline, Web of Science, EMBASE, Cochrane Library, from inception to 2 January 2022. Literature was screened according to the PICOS principle, followed by literature quality evaluation to assess the risk of bias. Finally, the outcome indicators of each study were extracted for combined analysis.Results: 9 studies were included in the current analysis. The results of the pooled analysis showed that the improvements in both primary and secondary indicators except for Bayley Scales of Infant and Toddler Development were more skewed towards stem cell therapy than the control group. In the subgroup analysis, the results showed that stem cell therapy significantly increased Gross Motor Function Measure (GMFM) scores of 3, 6, and 12 months. Besides, improvements in GMFM scores were more skewed toward umbilical cord mesenchymal stem cells, low dose, and intrathecal injection. Importantly, there was no significant difference in the adverse events (RR = 1.13; 95% CI = [0.90, 1.42]) between the stem cell group and the control group.Conclusion: The results suggested that stem cell therapy for cerebral palsy was safe and effective. Although the subgroup analysis results presented guiding significance in the selection of clinical protocols for stem cell therapy, high-quality RCTs validations are still needed

Depressive symptoms, social support, and health-related quality of life: A community-based study in Shanghai, China

BackgroundDepressive symptoms erode both physical and mental aspects of health-related quality of life (HRQoL). Social support (SS) may improve HRQoL through its direct effects or buffering effects. The association among depressive symptoms, SS, and HRQoL has been studied in specific groups, but research in the general adult population remains limited. This study examined the association among depressive symptoms, SS, and HRQoL, including exploring whether SS (including its three dimensions: subjective SS, objective SS and support utilization) mediated or moderated the relationship between depressive symptoms and HRQoL among community-based adults.MethodsWe conducted a cross-sectional survey in six communities in Shanghai, China, and 1642 adult participants with complete information on depressive symptoms and/or SS, and HRQoL were included. Linear regression analysis was used to investigate the association among depressive symptoms, SS, and HRQoL. In addition, we explored the mediating and moderating role of SS in the relationship between depressive symptoms and HRQoL.ResultsMore depressive symptoms were associated with lower physical HRQoL (B = −0.64, p < .001) and lower mental HRQoL (B = −0.83, p < .001). SS (B = 0.07, p = .02), specifically subjective SS (B = 0.09, p = .03), was positively related to mental HRQoL. After adjusting for covariates, we found no evidence for a mediating role of SS in the relationship between depressive symptoms and HRQoL, while SS (subjective SS and objective SS) moderated the association between depressive symptoms and mental HRQoL.LimitationsDue to the low voluntary participation rate of employees, participants represented approximately 50% of the individuals approached, thus limiting the generalizability of our findings. Data collected through self-report scales could lead to information bias.ConclusionsSS does not appear to underlie the relationship between depressive symptoms and HRQoL. However, interventions to increase SS (in particular, subjective SS and objective SS) should be studied to determine whether they may be beneficial in alleviating the adverse impact of depressive symptoms on mental HRQoL