Cognitive and neural mechanisms of voluntary versus forced language switching in Chinese-English bilinguals: an fMRI study

The ecological validity of bilingual code-switching has garnered increasing attention in recent years. Contrary to traditional studies that have focused on forced language switching, emerging theories posit that voluntary switching may not incur such a cost. To test these claims and understand differences between forced and voluntary switching, the present study conducted a systematic comparison through both behavioral and neural perspectives. Utilizing fMRI alongside picture-naming tasks, our findings diverge from prior work. Voluntary language switching not only demonstrated switching costs at the behavioral level but also significantly activated brain regions associated with inhibitory control. Direct comparisons of voluntary and forced language switching revealed no significant behavioral differences in switching costs, and both shared several common brain regions that were activated. On the other hand, a nuanced difference between the two types of language switching was revealed by whole-brain analysis: voluntary switching engaged fewer language control regions than forced switching. These findings offer a comprehensive view of the neural and behavioral dynamics involved in bilingual language switching, challenging prior claims that voluntary switching imposes no behavioral or neural costs, and thus providing behavioral and neuroimaging evidence for the involvement of inhibitory control in voluntary language switching.

Danlou Recipe promotes cholesterol efflux in macrophages RAW264.7 and reverses cholesterol transport in mice with hyperlipidemia induced by P407

INTRODUCTION

Liver X Receptor (LXR) agonists could attenuate the development of atherosclerosis but bring excess lipid accumulation in the liver. Danlou Recipe was believed to be a benefit for improving the lipid profile. Thus, it is unclear whether Danlou Recipe could attenuate hyperlipidemia without excess lipid accumulated in the liver of mice. This study aimed to clarify if Danlou Recipe could alleviate the progression of hyperlipidemia in mice without extra lipids accumulated in the liver.

METHODS

Male murine macrophage RAW264.7 cells and murine peritoneal macrophages were used for the in vitro experiments. Cellular cholesterol efflux was determined using the fluorescent cholesterol labeling method. Those genes involved in lipid metabolism were evaluated by qRT-PCR and western blotting respectively. In vivo, a mouse model of hyperlipidemia induced by P407 was used to figure out the effect of Danlou Recipe on reverse cholesterol transport (RCT) and hyperlipidemia. Ethanol extract of Danlou tablet (EEDL) was prepared by extracting the whole powder of Danlou Prescription from ethanol, and the chemical composition was analyzed by ultra-performance liquid chromatography (UPLC).

RESULTS

EEDL inhibits the formation of RAW264.7 macrophage-derived foam cells, and promotes ABCA1/apoA1 conducted cholesterol efflux in RAW264.7 macrophages and mouse peritoneal macrophages. In the P407-induced hyperlipidemia mouse model, oral administration of EEDL can promote RCT in vivo and improve fatty liver induced by a high-fat diet. Consistent with the findings in vitro, EEDL promotes RCT by upregulating the LXR activities.

CONCLUSION

Our results demonstrate that EEDL has the potential for targeting RCT/LXR in the treatment of lipid metabolism disorders to be developed as a safe and effective therapy.

Mammary Development and Breast Cancer: a Notch Perspective

Mammary gland development primarily occurs postnatally, and this unique process is complex and regulated by systemic hormones and local growth factors. The mammary gland is also a highly dynamic organ that undergoes profound changes at puberty and during the reproductive cycle. These changes are driven by mammary stem cells (MaSCs). Breast cancer is one of the most common causes of cancer-related death in women. Cancer stem cells (CSCs) play prominent roles in tumor initiation, drug resistance, tumor recurrence, and metastasis. The highly conserved Notch signaling pathway functions as a key regulator of the niche mediating mammary organogenesis and breast neoplasia. In this review, we discuss mechanisms by which Notch contributes to breast carcinoma pathology and suggest potentials for therapeutic targeting of Notch in breast cancer. In summary, we provide a comprehensive overview of Notch functions in regulating MaSCs, mammary development, and breast cancer.

The American Paddlefish Genome Provides Novel Insights into Chromosomal Evolution and Bone Mineralization in Early Vertebrates

Sturgeons and paddlefishes (Acipenseriformes) occupy the basal position of ray-finned fishes, although they have cartilaginous skeletons as in Chondrichthyes. This evolutionary status and their morphological specializations make them a research focus, but their complex genomes (polyploidy and the presence of microchromosomes) bring obstacles and challenges to molecular studies. Here, we generated the first high-quality genome assembly of the American paddlefish (Polyodon spathula) at a chromosome level. Comparative genomic analyses revealed a recent species-specific whole-genome duplication event, and extensive chromosomal changes, including head-to-head fusions of pairs of intact, large ancestral chromosomes within the paddlefish. We also provide an overview of the paddlefish SCPP (secretory calcium-binding phosphoprotein) repertoire that is responsible for tissue mineralization, demonstrating that the earliest flourishing of SCPP members occurred at least before the split between Acipenseriformes and teleosts. In summary, this genome assembly provides a genetic resource for understanding chromosomal evolution in polyploid nonteleost fishes and bone mineralization in early vertebrates.

COVID-19 diagnostic testing: Technology perspective

The corona virus disease 2019 (COVID-19) is a highly contagious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More than 18 million people were infected with a total of 0.7 million deaths in ∼188 countries. Controlling the spread of SARS-CoV-2 is therefore inherently dependent on identifying and isolating infected individuals, especially since COVID-19 can result in little to no symptoms. Here, we provide a comprehensive review of the different primary technologies used to test for COVID-19 infection, discuss the advantages and disadvantages of each technology, and highlight the studies that have employed them. We also describe technologies that have the potential to accelerate SARS-CoV-2 detection in the future, including digital PCR, CRISPR, and microarray. Finally, remaining challenges in COVID-19 diagnostic testing are discussed, including (a) the lack of universal standards for diagnostic testing; (b) the identification of appropriate sample collection site(s); (c) the difficulty in performing large population screening; and (d) the limited understanding of SARS-COV-2 viral invasion, replication, and transmission.

The SAUR41 subfamily of SMALL AUXIN UP RNA genes is abscisic acid inducible to modulate cell expansion and salt tolerance in Arabidopsis thaliana seedlings

BACKGROUND AND AIMS

Most primary auxin response genes are classified into three families: AUX/IAA, GH3 and SAUR genes. Few studies have been conducted on Arabidopsis thaliana SAUR genes, possibly due to genetic redundancy among different subfamily members. Data mining on arabidopsis transcriptional profiles indicates that the SAUR41 subfamily members of SMALL AUXIN UP RNA genes are, strikingly, induced by an inhibitory phytohormone, abscisic acid (ABA). We aimed to reveal the physiological roles of arabidopsis SAUR41 subfamily genes containing SAUR40, SAUR41, SAUR71 and SAUR72.

METHODS

Transcriptional responses of arabidopsis SAUR41 genes to phytohormones were determined by quantitative real-time PCR. Knock out of SAUR41 genes was carried out with the CRISPR/Cas9 (clustered regulatory interspaced short palindromic repeats/CRISPR-associated protein 9) genome editing technique. The saur41/40/71/72 quadruple mutants, SAUR41 overexpression lines and the wild type were subjected to ultrastructural observation, transcriptome analysis and physiological characterization.

KEY RESULTS

Transcription of arabidopsis SAUR41 subfamily genes is activated by ABA but not by gibberellic acids and brassinosteroids. Quadruple mutations in saur41/40/71/72 led to reduced cell expansion/elongation in cotyledons and hypocotyls, opposite to the overexpression of SAUR41; however, an irregular arrangement of cell size and shape was observed in both cases. The quadruple mutants had increased transcription of calcium homeostasis/signalling genes in seedling shoots, and the SAUR41 overexpression lines had decreased transcription of iron homeostasis genes in roots and increased ABA biosynthesis in shoots. Notably, both the quadruple mutants and the SAUR41 overexpression lines were hypersensitive to salt stress during seedling establishment, whereas specific expression of SAUR41 under the ABA-responsive RD29A (Responsive to Desiccation 29A) promoter in the quadruple mutants rescued the inhibitory effect of salt stress.

CONCLUSIONS

The SAUR41 subfamily genes of arabidopsis are ABA inducible to modulate cell expansion, ion homeostasis and salt tolerance. Our work may provide new candidate genes for improvement of plant abiotic stress tolerance.

Sustained IFN-I stimulation impairs MAIT cell responses to bacteria by inducing IL-10 during chronic HIV-1 infection

Mucosal-associated invariant T (MAIT) cells in HIV-1-infected individuals are functionally impaired by poorly understood mechanisms. Single-cell transcriptional and surface protein analyses revealed that peripheral MAIT cells from HIV-1-infected subjects were highly activated with the up-regulation of interferon (IFN)-stimulated genes as compared to healthy individuals. Sustained IFN-α treatment suppressed MAIT cell responses to Escherichia coli by triggering high-level interleukin-10 (IL-10) production by monocytes, which subsequently inhibited the secretion of IL-12, a crucial costimulatory cytokine for MAIT cell activation. Blocking IFN-α or IL-10 receptors prevented MAIT cell dysfunction induced by HIV-1 exposure in vitro. Moreover, blocking the IL-10 receptor significantly improved anti-Mycobacterium tuberculosis responses of MAIT cells from HIV-1-infected patients. Our findings demonstrate the central role of the IFN-I/IL-10 axis in MAIT cell dysfunction during HIV-1 infection, which has implications for the development of anti-IFN-I/IL-10 strategies against bacterial coinfections in HIV-1-infected patients.

Genome-wide identification and functional analysis of oleosin genes in Brassica napus L

BACKGROUND

Rapeseed is the third largest oil seed crop in the world. The seeds of this plant store lipids in oil bodies, and oleosin is the most important structural protein in oil bodies. However, the function of oleosin in oil crops has received little attention.

RESULTS

In the present study, 48 oleosin sequences from the Brassica napus genome were identified and divided into four lineages (T, U, SH, SL). Synteny analysis revealed that most of the oleosin genes were conserved, and all of these genes experienced purifying selection during evolution. Three and four important oleosin genes from Arabidopsis and B. napus, respectively, were cloned and analyzed for function in Arabidopsis. Overexpression of these oleosin genes in Arabidopsis increased the seed oil content slightly, except for BnaOLE3. Further analysis revealed that the average oil body size of the transgenic seeds was slightly larger than that of the wild type (WT), except for BnaOLE1. The fatty acid profiles showed that the linoleic acid content (13.3% at most) increased and the peanut acid content (11% at most) decreased in the transgenic lines. In addition, the seed size and thousand-seed weight (TSW) also increased in the transgenic lines, which could lead to increased total lipid production.

CONCLUSION

We identified oleosin genes in the B. napus genome, and overexpression of oleosin in Arabidopsis seeds increased the seed weight and linoleic acid content (13.3% at most).

Molecular characterization and expression of six heat shock protein genes in relation to development and temperature in Trichogramma chilonis

Trichogramma is a kind of egg parasitoid wasp that is widely used to control lepidopterous pests. Temperature is one of the main factors that determines the various life activities of this species, including development, reproduction and parasitism efficiency. Heat shock proteins (HSPs) are highly conserved and ubiquitous proteins that are best known for their responsiveness to temperature and other stresses. To explore the potential role of HSPs in Trichogramma species, we obtained the full-length cDNAs of six HSP genes (Tchsp10, Tchsp21.6, Tchsp60, Tchsp70, Tchsc70-3, and Tchsp90) from T. chilonis and analyzed their expression patterns during development and exposure to temperature stress. The deduced amino acid sequences of these HSP genes contained the typical signatures of their corresponding protein family and showed high homology to their counterparts in other species. The expression levels of Tchsp10, Tchsp21.6 and Tchsp60 decreased during development. However, the expression of Tchsc70-3 increased from the pupal stage to the adult stage. Tchsp70 and Tchsp90 exhibited the highest expression levels in the adult stage. The expression of six Tchsps was dramatically upregulated after 1 h of exposure to 32 and 40°C but did not significantly change after 1 h of exposure to 10 and 17°C. This result indicated that heat stress, rather than cold stress, induced the expression of HSP genes. Furthermore, the expression of these genes was time dependent, and the expression of each gene reached its peak after 1 h of heat exposure (40°C). Tchsp10 and Tchsp70 exhibited a low-intensity cold response after 4 and 8 h of exposure to 10°C, respectively, but the other genes did not respond to cold at any time points. These results suggested that HSPs may play different roles in the development of this organism and in its response to temperature stress.

Production of Acetoin through Simultaneous Utilization of Glucose, Xylose, and Arabinose by Engineered Bacillus subtilis

Glucose, xylose and arabinose are the three most abundant monosaccharide found in lignocellulosic biomass. Effectively and simultaneously utilization of these sugars by microorganisms for production of the biofuels and bio-chemicals is essential toward directly fermentation of the lignocellulosic biomass. In our previous study, the recombinant Bacillus subtilis 168ARSRCPΔacoAΔbdhA strain was already shown to efficiently utilize xylose for production of acetoin, with a yield of 0.36 g/g xylose. In the current study, the Bacillus subtilis168ARSRCPΔacoAΔbdhA strain was further engineered to produce acetoin from a glucose, xylose, and arabinose mixtures. To accomplish this, the endogenous xylose transport protein AraE, the exogenous xylose isomerase gene xylA and the xylulokinase gene xylB from E. coli were co-overexpressed in the Bacillus subtilis 168ARSRCPΔacoAΔbdhA strain, which enabled the resulting strain, denoted ZB02, to simultaneously utilize glucose and xylose. Unexpectedly, the ZB02 strain could simultaneously utilize glucose and arabinose also. Further results indicated that the transcriptional inhibition of the arabinose transport protein gene araE was the main limiting factor for arabinose utilization in the presence of glucose. Additionally, the arabinose operon in B. subtilis could be activated by the addition of arabinose, even in the presence of glucose. Through fed-batch fermentation, strain ZB02 could simultaneously utilize glucose, xylose, and arabinose, with an average sugar consumption rate of 3.00 g/l/h and an average production of 62.2 g/l acetoin at a rate of 0.864 g/l/h. Finally, the strain produced 11.2 g/l acetoin from lignocellulosic hydrolysate (containing 20.6g/l glucose, 12.1 g/l xylose and 0.45 g/l arabinose) in flask cultivation, with an acetoin yield of 0.34 g/g total sugar. The result demonstrates that this strain has good potential for the utilization of lignocellulosic hydrolysate for production of acetoin.

Above- and Belowground Biomass Allocation in Shrub Biomes across the Northeast Tibetan Plateau

Biomass partitioning has been explored across various biomes. However, the strategies of allocation in plants still remain contentious. This study investigated allocation patterns of above- and belowground biomass at the community level, using biomass survey from the Tibetan Plateau. We explored above- and belowground biomass by conducting three consecutive sampling campaigns across shrub biomes on the northeast Tibetan Plateau during 2011-2013. We then documented the above-ground biomass (AGB), below-ground biomass (BGB) and root: shoot ratio (R/S) and the relationships between R/S and environment factors using data from 201 plots surveyed from 67 sites. We further examined relationships between above-ground and below-ground biomass across various shrub types. Our results indicated that the median values of AGB, BGB, and R/S in Tibetan shrub were 1102.55, 874.91 g m-2, and 0.85, respectively. R/S showed significant trend with mean annual precipitation (MAP), while decreased with mean annual temperature (MAT). Reduced major axis analysis indicated that the slope of the log-log relationship between above- and belowground biomass revealed a significant difference from 1.0 over space, supporting the optimal hypothesis. Interestingly, the slopes of the allometric relationship between log AGB and log BGB differed significantly between alpine and desert shrub. Our findings supported the optimal theory of above- and belowground biomass partitioning in Tibetan shrub, while the isometric hypothesis for alpine shrub at the community level.