Small RNA-mediated genome rearrangement pathways in ciliates.

Most eukaryotes employ a combination of transcriptional and post-transcriptional silencing mechanisms to suppress transposons, yet ciliates employ a more extreme approach. They separate germline and somatic functions into distinct nuclei, enabling the elimination of transposons from the active somatic genome through diverse small RNA-mediated genome rearrangement pathways during sexual processes.

SIRT6 Inhibits Anoikis of Colorectal Cancer Cells by Down-Regulating NDRG1.

Anoikis, a form of apoptosis resulting from the loss of cell-extracellular matrix interaction, is a significant barrier to cancer cell metastasis. However, the epigenetic regulation of this process remains to be explored. Here, we demonstrate that the histone deacetylase sirtuin 6 (SIRT6) plays a pivotal role in conferring anoikis resistance to colorectal cancer (CRC) cells. The protein level of SIRT6 is negatively correlated with anoikis in CRC cells. The overexpression of SIRT6 decreases while the knockdown of SIRT6 increases detachment-induced anoikis. Mechanistically, SIRT6 inhibits the transcription of N-myc downstream-regulated gene 1 (NDRG1), a negative regulator of the AKT signaling pathway. We observed the up-regulation of SIRT6 in advanced-stage CRC samples. Together, our findings unveil a novel epigenetic program regulating the anoikis of CRC cells.

ACSL4 promotes microglia-mediated neuroinflammation by regulating lipid metabolism and VGLL4 expression.

Acyl-CoA synthetase long-chain family member 4 (ACSL4) is an important isozyme in polyunsaturated fatty acid (PUFA) metabolism. The role of ACSL4 in the lipopolysaccharide (LPS)-induced inflammation of microglia, and the effects of ACSL4-mediated inflammation on the progression of Parkinson's disease (PD) are unknown. In this study, we found that ACSL4 expression was increased after LPS stimulation. Knocking down ACSL4 in microglia decreased proinflammatory cytokine production. Mechanistically, ACSL4 reduced vestigial-like family member 4(VGLL4) expression to promote NF-κB signal transduction; and ACSL4 regulated lipid composition after LPS stimulation. In addition, knocking down ACSL4 alleviated neuroinflammation in a systemic LPS model and acute l-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP) model. These data revealed ACSL4 to be a novel regulator that promotes microglia-mediated neuroinflammation by regulating VGLL4 expression and lipid metabolism.

Global mortality of diabetic foot ulcer: A systematic review and meta-analysis of observational studies.

AIM: To estimate the long-term mortality and risk factors in patients with diabetic foot ulcer (DFU). METHODS: We systematically searched Medline (PubMed), Embase, Scopus, Web of Science, Cochrane Library, China Science and Technology Journal Database (CQVIP), China National Knowledge Infrastructure, the Chinese Biomedical Literature Database (SinoMed) and Wanfang Data from 1 January 2011 to 31 July 2022. All observational studies that reported long-term mortality of patients with DFU were included. Random effect models were used to pool the reconstructed participant data from Kaplan-Meier curves. The primary outcome was the long-term survival of patients with DFU. An aggregate data meta-analysis was also performed. RESULTS: We identified 34 studies, with 124 376 participants representing 16 countries, among whom there were 51 386 deaths. Of these, 27 studies with 21 171 patients were included in the Kaplan-Meier-based meta-analysis. The estimated Kaplan-Meier-based survival rates were 86.9% (95% confidence interval [CI] 82.6%-91.5%) at 1 year, 66.9% (95% CI 59.3%-75.6%) at 3 years, 50.9% (95% CI 42.0%-61.7%) at 5 years and 23.1% (95% CI 15.2%-34.9%) at 10 years. The results of the aggregate data-based meta-analysis were similar. Cardiovascular disease and infection were the most common causes of death, accounting for 46.6% (95% CI 33.5%-59.7%) and 24.8% (95% CI 16.0%-33.5%), respectively. Patients with older age (per 1 year, hazard ratio [HR] 1.054, 95% CI 1.045-1.063), peripheral artery disease (HR 1.882, 95% CI 1.592-2.225), chronic kidney disease (HR 1.535, 95% CI 1.227-1.919), end-stage renal disease (HR 3.586, 95% CI 1.333-9.643), amputation (HR 2.415, 95% CI 1.323-4.408) and history of cardiovascular disease (HR 1.449, 95% CI 1.276-1.645) had higher mortality risk. CONCLUSIONS: This meta-analysis found that the overall mortality of DFU was high, with nearly 50% mortality within 5 years. Cardiovascular disease and infection were the two leading causes of death.

A novel isoform of hydroxyacyl-CoA dehydrogenase inhibits cell proliferation.

Hydroxyacyl-CoA dehydrogenase (HADH) catalyzes the third reaction of mitochondrial ß-oxidation cascade, while the regulation of its expression and function remains to be elucidated. Using the quantitative translation initiation sequencing (QTI-seq), we have identified that murine Hadh mRNA has two alternative translation start codons. We demonstrated that translation from upstream start codon encodes the mitochondrial isoform of HADH, while translation from downstream start codon produces a short isoform (HADH-S) with predominant nuclear localization. Moreover, overexpression of HADH-S inhibits the proliferation of mouse embryonic fibroblasts. Overall, our results identify a novel isoform of HADH participating in cell proliferation.

[Experimental Study of Using Aloe Vera Gel to Treat Diabetic Chronic Cutaneous Ulcers in Bama Miniature Pigs].

Objective: To investigate the efficacy, safety, and mechanism of topical application of aloe vera gel (AVG) to treat diabetic chronic cutaneous ulcers in Bama miniature pigs. Methods: The Bama miniature pig model of diabetic chronic skin wounds was constructed and the model pigs were randomly assigned to AVG daily administration group (AVG QD), aloe vera gel every-other-day administration group (AVG QOD), and diabetic control group (DC). A non-diabetic chronic skin wounds model pig was set as the non-diabetic control group (NDC). Treatment efficacy was evaluated based on the amount of time needed for complete healing of the wounds, healing rates, granulation growth rates, and skin histopathological changes. Safety was evaluated according to whether adverse reactions were observed. In addition, the dynamic changes of the relative expression levels of miR21, miR29a, miR126, miR146a, miR155, and miR210 in wound granulation tissues were examined. Results: 1) Efficacy and safety: The amount of time needed for complete healing of the wounds was shorter in the NDC group than those of the three other groups, DC group, AVG QD group, and AVG QOD group (all P<0.05). The amount of time needed for complete healing of the wounds was shorter in the AVG QD group and AVG QOD group than that of DC group (all P<0.05). The amount of time needed for complete healing of the wounds was shorter in the AVG QOD group than that of AVG QD group (all P<0.05). No adverse reactions were detected in the whole process of AVG topical treatment. The granulation growth rate of NDC group was higher than those of DC group, AVG QD group, and AVG QOD group (all P<0.05). The wound healing rate of NDC group was higher than those of DC group, AVG QD group, and AVG QOD group (all P<0.05); the wound healing rate of AVG QOD group was higher than those of DC group and AVG QD group (all P<0.05). 2) Histopathology: The results of HE staining light microscopy showed that collagen fiber production increased, and that microvascular formation with slight inflammatory cell infiltration was observed in the dermal interstitium at the initial stage of wound healing after AVG treatment. One year of after complete healing, pathological examination results of wound healing skin showed that the epidermal keratinization was complete, that collagen was arranged neatly and orderly, and that many microvessels were found in the interstitium. The results of picric acid celestite scarlet staining showed that, after AVG treatment, type Ⅰ collagen mainly increased in the initial stage of wound healing, type Ⅲ collagen gradually increased when the wound healed completely, and the collagen was arranged neatly during the whole process. 3) The relative expression of microRNAs: The relative expression of miR21, miR126, and miR210 in NDC group, AVG QD group, and AVG QOD group were higher than that in DC group (all P<0.05). The relative expression of miR29a and miR155 in NDC group, AVG QD group, and AVG QOD group was lower than that in DC group (all P<0.05). The relative expression of miR146a in NDC group was higher than that in DC group ( P<0.05). Conclusion: AVG topical application can shorten the time needed for complete healing of diabetic chronic wounds in Bama minipigs. The wound healing speed of the alternate-day treatment group was faster than that of the daily treatment group. No adverse reactions were observed over the course of the treatment. The mechanism may be related to the up-regulation of the expressions of miR21, miR126, and miR210 and the down-regulation of miR29a and miR155 in wound granulation tissue.

YTHDF1-regulated expression of TEAD1 contributes to the maintenance of intestinal stem cells.

N6-methyladenosine (m6A) mRNA modification has been defined as a crucial regulator in various biological processes. Recent studies indicated an essential role of YTHDF1, an m6A reader, in the maintenance of intestinal stem cells (ISCs), while the detailed mechanism remains to be explored. By searching our m6A sequencing, RNA sequencing, and ribosome profiling data, we identified the transcriptional enhanced associate domain 1 (TEAD1) as a direct target of YTHDF1. We confirmed the presence of m6A modifications in TEAD1 mRNA and its binding with YTHDF1. Knockdown of either m6A methyltransferase METTL3 or YTHDF1 reduced the translation of TEAD1. TEAD1 was highly expressed in ISCs, while depletion of TEAD1 inhibited proliferation and induced differentiation of organoids. Overexpression of TEAD1 reversed the impaired stemness elicited by YTHDF1 depletion. These findings identify TEAD1 as a functional target of m6A-YTHDF1 in sustaining intestinal stemness.

Large-scale phylogenomic analysis provides new insights into the phylogeny of the class Oligohymenophorea (Protista, Ciliophora) with establishment of a new subclass Urocentria nov. subcl.

The class Oligohymenophorea is one of the most diverse assemblage of ciliated protists, which are particularly important in fundamental biological studies including understanding the evolutionary relationships among the lineages. Phylogenetic relationships within the class remain largely elusive, especially within the subclass Peniculia, which contains the long-standing problematic taxa Urocentrum and Paranassula. In the present study, we sequenced the genomes and/or transcriptomes of six non-culturable oligohymenophoreans using single-cell sequencing techniques. Phylogenomic analysis was performed based on expanded taxon sampling of 85 taxa, including 157 nuclear genes encoding 36,953 amino acids. The results indicate that: (1) urocentrids form an independent branch that is sister to the clade formed by Scuticociliatia and Hymenostomatia, which, together with the morphological data, supports the establishment of a new subclass, Urocentria n. subcl., within Oligohymenophorea; (2) phylogenomic analysis and ortholog comparison reveal a close relationship between Paranassula and peniculines, providing corroborative evidence for removing Paranassula from Nassulida and elevating it as an order, Paranassulida, within the subclass Peniculia; (3) based on the phylogenomic analyses and morphological data, we hypothesize that Peritrichia is the earliest diverging clade within Oligohymenophorea while Scuticociliatia and Hymenostomatia share the most common ancestor, followed successively by Urocentria and Peniculia. In addition, stop codon analyses indicate that oligohymenophoreans widely use UGA as the stop codon, while UAR are reassigned to glutamate (peritrichs) or glutamine (others), supporting the evolutionary hypothesis.

Functional Ecology of Two Contrasting Freshwater Ciliated Protists in Relation to Temperature.

We conducted microcosm experiments with two contrasting freshwater ciliates on functional traits (FTs) related to their growth rate (numerical response, NR) and ingestion rate (functional response, FR) over a range of ecologically relevant temperatures. Histiobalantium bodamicum and Vorticella natans are common planktonic ciliates but their abundance, swimming behavior, and temperature tolerance are different. In contrast to most sessile peritrich species, the motile V. natans is not strictly bacterivorous but also voraciously feeds upon small algae. We observed three main alterations in the shape of NR of both species with temperature, that is, change in the maximum growth rate, in the initial slope and in the threshold food level needed to sustain the population. Similarly, maximum ingestion rate, gross growth efficiency (GGE), and cell size varied with temperature and species. These findings caution against generalizing ciliate performance in relation to the ongoing global warming. Our results suggest that V. natans is the superior competitor to H. bodamicum in terms of temperature tolerance and bottom-up control. However, the abundance of V. natans is usually low compared to H. bodamicum and other common freshwater ciliates, suggesting that V. natans is more strongly top-down controlled via predation than H. bodamicum. The taxonomic position of V. natans has been debated. Therefore, to confirm species and genus affiliation of our study objects, we sequenced their small subunit ribosomal RNA (SSU rDNA) gene.

Inhomogeneous Distribution of Cationic Surfactants around Anionic Molecular Clusters.

An interesting phenomenon is reported when uranyl peroxide nanoclusters U60 (Li48+m K12 (OH)m [UO2 (O2 )(OH)]60 (H2 O)n , m≈20 and n≈310) interact with a small number of cationic surfactant molecules. Cationic surfactant molecules do not distribute evenly around the U60 clusters during the interaction as expected. Instead, a small fraction of U60 clusters attract almost all the surfactant molecules, leading to the self-assembly into supramolecular structures by using surfactant-U60 complexes as building locks, and later further aggregate and precipitate based on hydrophobic interaction, whereas the rest of the clusters remained unbounded soluble macroions in bulk dispersion. This phenomenon nicely demonstrates a unique feature of macroion solutions. Considering that Debye-Hückel approximation is no longer valid in such solutions, the competition between the local electrostatic interaction and hydrophobic interaction becomes important to regulate the solution behaviors of macroions.

Isotope and Hydrogen-Bond Effects on the Self-Assembly of Macroions in Dilute Solution.

We report on the disparity in the assembly behavior of four types of nano-sized macroions induced by isotopic substitution of protium (H) to deuterium (D) in solvents. Macroions with modest charge density can self-assemble into single-layer, hollow, spherical "blackberry"-type structures, with larger assembly sizes representing stronger attractions among the macroions. Kinetically, all assembly processes become slower in D2 O than in H2 O. Thermodynamically, the polyoxometalate {SrPd12 }, the uranium cage {U60 } with alkali metal counterions, and the metal-organic cationic cage {Pd12 L24 } demonstrate similar assembly sizes in both H2 O and D2 O, whereas the metal oxide cluster {Mo72 Fe30 } as a weak acid shows an unusually large assembly size in H2 O-suggesting a stronger contribution from the hydrogen bonding in the last case.

[Predictive Value of Obesity Indicators for Metabolic Syndrome in Adults of Han and Yi Nationalities in Sichuan].

OBJECTIVE: To compare the predictive value of different measures of obesity for metabolic syndrome (MetS) in adult Yi and Han nationality population. METHODS: A total of 3 492 urban and rural residents in Chengdu and Liangshan Yi Autonomous Prefecture participated in this study. Demographic and laboratory data were collected. Spearman correlation analysis was used to investigate the relationship between different obesity measurement indexes and MetS. Receiver operating characteristic (ROC) curve was used to compare the predictive value between different obesity measurement indexes. RESULTS: Spearman correlation analysis showed that MetS was related to body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), lipid accumulation index (LAP) and visceral adiposity index (VAI). The ROC curve showed that the LAP had the highest predictive value for MetS in both Yi and Han male adults, area under the curves (AUCs) >0.90; whereas WHR had the lowest predictive value. WHtR had high predictive value for MetS in both Yi and Han female adults (AUCs >0.88), VAI had the worst predictive value. CONCLUSION: Among different measures of obesity, LAP may have the optimal predictive value for MetS in male adults as do WHtR in female adults either in Yi or Han nationality. These findings should be confirmed through the measure of visceral fat volume and prospective study.

Expanding the Schulze-Hardy Rule and the Hofmeister Series to Nanometer-Scaled Hydrophilic Macroions.

The Schulze-Hardy rule is a well-established observation in colloid science (can be derived from the DLVO theory) that demonstrates the relationship between the critical coagulation concentration (CCC) of colloids and the valence of extra counterionic electrolytes (z), with a simple mathematical relationship of CCC≈z-6 . Here the Schulze-Hardy Rule is expanded to much smaller, nano-scaled soluble macroions in aqueous solution, by examining the stability of the macroions in the presence of additional electrolytes. The CCC values of the macroions follow the general trend of CCC≈z-n but the n value is significantly dependent on the surface charge density of the macroions, ranging from n=2 at very low surface charge density to n=6 at a high surface charge density. In addition, different cations with the same valence showed clear different impacts on the CCC values, with an interesting trend being connected to the Hofmeister series originally discovered in protein solutions.

Strong Co-Ion Effect via Cation-π Interaction on the Self-Assembly of Metal-Organic Cationic Macrocycles.

The predesigned metal-organic macrocycle Zn3QDB3(NO3)4 (Zn-QDB) was observed to self-assemble into a hollow, spherical, single-layered "blackberry"-type structure. The self-assembly behaviors of the Zn-QDB are significantly influenced by additional small ions. Specifically, the cations exhibit strong co-ion effects on the interaction between cationic macrocycles which are different from the previously reported co-ion effects of simple anions on anionic polyoxometalates. This unusual phenomenon is due to the unique cation-π interaction between small cations and electron-rich cavity of Zn-QDB, as confirmed by UV-vis, 1H NMR, and fluorescence spectra. The variation of hydrodynamic radius (Rh) of assemblies with the changes of solution ionic strength and the type of cations reveals the competition between counterion-mediated attraction and cation-π interaction during the self-assembly process. Furthermore, the cooperativity of cation-π interaction and π-π stacking play a vital role in enhancing the stability of the supramolecular structure.

A Spontaneous Structural Transition of {U24 Pp12 } Clusters Triggered by Alkali Counterion Replacement in Dilute Solution.

A transition between two isomeric clusters involving the change of the main skeleton structure of a well-defined, rigid molecular cluster [(UO2 )24 (O2 )24 (P2 O7 )12 ]48- , {U24 Pp12 }, is achieved by simply introducing proper alkali cations into its dilute aqueous solution. While the unique structural transition can be triggered by introducing any of the Na+ /K+ /Rb+ /Cs+ alkali ions, the two isomers, Li/Na-{U24 Pp12 } and Na/K-{U24 Pp12 }, as typical macroions, can accurately choose among different alkali counter-cations based on their hydrated sizes, and the ion selectivity process clearly showed endothermic features. The preferred K+ and Rb+ ions have suitable sizes to be incorporated into the proper windows on {U24 Pp12 } nanocapsules, as supported by the transition points in both ITC studies and IR measurements.

[A Study on the Feasibility to Assay Minipig Insulin Through Human Insulin Radioimmunoassay Kit].

OBJECTIVES: To investigate the feasibility of using human-specific insulin radioimmunoassay (Ins-RIA) kit to measure the concentrations of serum insulin in minipigs. METHODS: The Serum samples (219) of Bama minipigs were collected. The concentrations of serum insulin in Bama minipigs were measured by Ins-RIA kit and porcine-specific insulin enzyme linked immunosorbent assay (Ins-ELISA) kit, respectively. The linear regression analysis was undertaken in a randomly selected 175 samples (80% of total samples) to establish predictive equations between the concentrations of serum insulin measured by Ins-ELISA and the concentrations of serum insulin measured by Ins-RIA. The equations were then cross-validated in the remaining 44 samples (20% of total samples) that had not been included in the regression analysis. RESULTS: Measured insulin concentration was lower with the Ins-ELISA than that with the Ins-RIA [(15.32±15.50) µIU/mL vs. (32.31±21.74) µIU/mL, respectively, P<0.000 1]; The final predictive equation for the Ins-ELISA (µIU/mL) was equal to -7.29+0.70 × Ins-RIA(µIU/mL) ( R2=0.94). The differences between the predicted values and the actual measured values were 17.18%. CONCLUSIONS: Insulin values in Bama minipigs obtained from the Ins-ELISA and Ins-RIA are not equivalent and differ significantly. However, the insulin concentration by Ins-ELISA can be well estimated by Ins-RIA.

Thermal Responsive Ion Selectivity of Uranyl Peroxide Nanocages: An Inorganic Mimic of K(+) Ion Channels.

An actinyl peroxide cage cluster, Li48+m K12 (OH)m [UO2 (O2 )(OH)]60 (H2 O)n (m≈20 and n≈310; U60 ), discriminates precisely between Na(+) and K(+) ions when heated to certain temperatures, a most essential feature for K(+) selective filters. The U60 clusters demonstrate several other features in common with K(+) ion channels, including passive transport of K(+) ions, a high flux rate, and the dehydration of U60 and K(+) ions. These qualities make U60 (a pure inorganic cluster) a promising ion channel mimic in an aqueous environment. Laser light scattering (LLS) and isothermal titration calorimetry (ITC) studies revealed that the tailorable ion selectivity of U60 clusters is a result of the thermal responsiveness of the U60 hydration shells.

Spontaneous Self-Assembly of γ-Cyclodextrins in Dilute Solutions with Tunable Sizes and Thermodynamic Stability.

The behavior in dilute solution of phosphate-functionalized γ-cyclodextrin macroanions with eight charges on the rim was explored. The hydrophilic macroions in mixed solvents show strong attraction between each other, mediated by the counterions, and consequently self-assemble into blackberry-type hollow spherical structures. Time-resolved laser light scattering (LLS) measurements at high temperature ruled out the possibility of hydrogen bonding as the main driving force in the self-assembly and indicated the good thermodynamic stability of assemblies regulated by the charge. The transition from single macroions to blackberries can be tuned by adjusting the content of organic solvent. The sizes of blackberries vary with the charge density of γ-cyclodextrin by adjusting pH. It is the first report that pure cyclodextrins can generate supramolecular structures by themselves in dilute solution. The unique solution behavior of macroions provides a new opportunity to assemble cyclodextrin into functional materials and devices.

Selective Permeability of Uranyl Peroxide Nanocages to Different Alkali Ions: Influences from Surface Pores and Hydration Shells.

The precise guidance to different ions across the biological channels is essential for many biological processes. An artificial nanopore system will facilitate the study of the ion-transport mechanism through nanosized channels and offer new views for designing nanodevices. Herein we reveal that a 2.5 nm-sized, fullerene-shaped molecular cluster Li48+m K12(OH)m [UO2(O2)(OH)]60-(H2O)n (m ≈ 20 and n ≈ 310) (U60) shows selective permeability to different alkali ions. The subnanometer pores on the water-ligand-rich surface of U60 are able to block Rb(+) and Cs(+) ions from passing through, while allowing Na(+) and K(+) ions, which possess larger hydrated sizes, to enter the interior space of U60. An interestingly high entropy gain during the binding process between U60 and alkali ions suggests that the hydration shells of Na(+)/K(+) and U60 are damaged during the interaction. The ion selectivity of U60 is greatly influenced by both the morphologies of the surface nanopores and the dynamics of the hydration shells.