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Cryptosporidium species can infect humans and more than 260 animal species, including 54 rodent species. However, data on the occurrence and genetic characterizations of Cryptosporidium spp. in laboratory rodents are limited. The present study aimed to determine the occurrence rate and genetic characterizations of Cryptosporidium spp. in laboratory mice and rats. We collected 506 fresh combined fecal pellet specimens (457 from mice and 49 from rats) of more than 2,000 laboratory rodents in Heilongjiang Province and Shanghai City, China. Cryptosporidium spp. were identified and subtyped by DNA sequencing of the SSU rRNA and the gp60 genes, respectively. By sequence analysis of the SSU rRNA gene, the occurrence rate of Cryptosporidium spp. was 16.6% (84/506) in combined fecal specimens, with 18.2% (83/457) for mice and 2.0% (1/49) for rats. Cryptosporidium parvum (n = 39), C. tyzzeri (n = 33), and C. parvum + C. tyzzeri (n = 11) were identified in mice. Cryptosporidium parvum was only detected in one rat fecal specimen. At the gp60 locus, 71.4% (60/84) of the Cryptosporidium-positive specimens were successfully amplified, and they all came from mice. We identified five C. parvum subtypes (IIaA14G2R1, IIaA16G2R1, IIaA17G1R1, IIaA17G2R1, and IIaA18G2R1) and two C. tyzzeri subtypes (IXaA6R1 and IXbA8). Based on the identification in laboratory mice of C. parvum subtypes that have been reported previously in humans, the mice infected with this species may threaten human health, especially for people who have contact with the animals and their feces.

Wild rodents serve as reservoirs for Cryptosporidium and are overpopulated globally. However, genetic data regarding Cryptosporidium in these animals from China are limited. Here, we have determined the prevalence and genetic characteristics of Cryptosporidium among 370 wild rodents captured from three distinct locations in the southern region of Zhejiang Province, China. Fresh feces were collected from the rectum of each rodent, and DNA was extracted from them. The rodent species was identified by PCR amplifying the vertebrate cytochrome b gene. Cryptosporidium was detected by PCR amplification and amplicon sequencing the small subunit of ribosomal RNA gene. Positive samples of C. viatorum and C. parvum were further subtyped by analyzing the 60-kDa glycoprotein gene. A positive Cryptosporidium result was found in 7% (26/370) of samples, involving five rodent species: Apodemus agrarius (36), Niviventer niviventer (75), Rattus losea (18), R. norvegicus (155), and R. tanezumi (86). Their respective Cryptosporidium positive rates were 8.3%, 5.3%, 11.1%, 7.1%, and 7.0%. Sequence analysis confirmed the presence of three Cryptosporidium species: C. parvum (4), C. viatorum (1), and C. muris (1), and two genotypes: Cryptosporidium rat genotype IV (16) and C. mortiferum-like (4). Additionally, two subtypes of C. parvum (IIdA15G1 and IIpA19) and one subtype of C. viatorum (XVdA3) were detected. These results demonstrate that various wild rodent species in Zhejiang were concurrently infected with rodent-adapted and zoonotic species/genotypes of Cryptosporidium, indicating that these rodents can play a role in maintaining and dispersing this parasite into the environment and other hosts, including humans.

Modular polyketide synthases and non-ribosomal peptide synthetases are molecular assembly lines that consist of several multienzyme subunits that undergo dynamic self-assembly to form a functional megacomplex. N- and C-terminal docking domains are usually responsible for mediating the interactions between subunits. Here we show that communication between two non-ribosomal peptide synthetase subunits responsible for chain release from the enacyloxin polyketide synthase, which assembles an antibiotic with promising activity against Acinetobacter baumannii, is mediated by an intrinsically disordered short linear motif and a β-hairpin docking domain. The structures, interactions and dynamics of these subunits were characterized using several complementary biophysical techniques to provide extensive insights into binding and catalysis. Bioinformatics analyses reveal that short linear motif/β-hairpin docking domain pairs mediate subunit interactions in numerous non-ribosomal peptide and hybrid polyketide-non-ribosomal peptide synthetases, including those responsible for assembling several important drugs. Short linear motifs and β-hairpin docking domains from heterologous systems are shown to interact productively, highlighting the potential of such interfaces as tools for biosynthetic engineering.

Background: The clinical value of myocardial torsion quantification in prognostic assessment and risk stratification of various cardiovascular diseases is gradually being recognized. However, normal values of left and right ventricular (LV and RV) torsion and torsion rates (TRs) have not been fully determined, and their correlation with age and gender has not been well studied. Purpose: To establish normal ranges of biventricular torsion, peak systolic and diastolic TRs using magnetic resonance feature tracking (MR‐FT) technique based on a large sample of healthy adults, and further investigate their relationship with age and gender. Study Type: Retrospective. Population: 566 Healthy adults (312 males, aged 43 ± 10 years; 254 females, aged 43 ± 11 years). Field Strength/Sequence: 1.5T/gradient echo. Assessment: Biventricular torsion, peak systolic, and diastolic TRs. Statistical Tests: Shapiro–Wilk test, Student's t‐test, Mann–Whitney‐U test, linear regression, intraclass correlation coefficient, Bland–Altman analysis. Differences were regarded as statistically significant at P < 0.05. Results: Women demonstrated greater magnitudes of left ventricle (LV) torsion (1.23 ± 0.44 vs. 1.00 ± 0.42°/cm), peak systolic TR (9.69 ± 3.70 vs. 8.27 ± 3.73°/cm*sec), peak diastolic TR (−7.78 ± 2.82 vs. −6.06 ± 2.44°/cm*sec), and RV torsion (2.20 ± 1.23 vs. 1.65 ± 1.11°/cm*sec), peak systolic TR (16.07 ± 8.18 vs. 12.62 ± 7.08°/cm*sec), peak diastolic TR (−15.39 ± 6.53 vs. −11.70 ± 6.03°/cm*sec). For both genders, the magnitudes of LV and RV torsion, peak systolic, and diastolic TRs increased linearly with age. All the measurements of biventricular torsion, peak systolic and diastolic TRs achieved good to excellent intraobserver and interobserver reproducibility, with all intraclass correlation coefficients >0.70. Data Conclusion: The present study systematically provided age‐ and sex‐stratified reference values for LV and RV torsion and TRs using MR‐FT technique. Women and aging are associated with greater magnitudes of biventricular torsion, peak systolic, and diastolic TRs. Level of Evidence: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

When a transformer is in a long-term heavy load operation state, the oil temperature reaches the alarm temperature; if a slight fault occurs inside the transformer, traditional inverse time current protection and other protections that react to phase current may not operate due to insufficient sensitivity or they may operate for too long. Based on this, this article proposes a new principle of accelerating inverse time overcurrent protection based on transformer oil temperature. The proposed method uses transformer oil temperature to accelerate the action time of traditional inverse-time overcurrent protection, then introduces the transformer oil temperature factor and acceleration index to optimize the inverse time characteristic curve, and establishes a mathematical model to optimize the adjustment for the complexity of adjustment of the protection action equation and the risk of mismatch of the protection after the acceleration of oil temperature. The existing theoretical analysis and simulation verification results show that the proposed new overcurrent protection scheme based on the transformer oil temperature acceleration inverse time can effectively improve the protection of the rapidity and sensitivity, providing a new research idea for the combination of non-electrical and electrical quantity protection. [ABSTRACT FROM AUTHOR]

Atherosclerosis, a slowly progressing inflammatory disease, is characterized by the presence of monocyte‐derived macrophages. Interventions targeting the inflammatory characteristics of atherosclerosis hold promising potential. Although interleukin (IL)‐10 is widely acknowledged for its anti‐inflammatory effects, systemic administration of IL‐10 has limitations due to its short half‐life and significant systemic side effects. In this study, we aimed to investigate the effectiveness of an approach designed to overexpress IL‐10 in macrophages and subsequently introduce these genetically modified cells into ApoE−/− mice to promote atherosclerosis regression. We engineered RAW264.7 cells to overexpress IL‐10 (referred to as IL‐10M) using lentivirus vectors. The IL‐10M exhibited robust IL‐10 secretion, maintained phagocytic function, improved mitochondrial membrane potentials, reduced superoxide production and showed a tendency toward the M2 phenotype when exposed to inflammatory stimuli. IL‐10M can selectively target plaques in ApoE−/− mice and has the potential to reduce plaque area and necrotic core at both early and late stages of plaque progression. Moreover, there was a significant reduction in MMP9, a biomarker associated with plaque rupture, in IL‐10M‐treated plaques from both the early and late intervention groups. Additionally, the administration of IL‐10M showed no obvious side effects. This study serves as proof that cell therapy based on anti‐inflammatory macrophages might be a promising strategy for the intervention of atherosclerosis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Okra contains flavonoids and vitamin C as antioxidants and it contains polysaccharides as immunomodulators. Flavonoids regulate the inflammatory response in mice and may be related to gut microbiota. This study therefore aimed to investigate the impact of okra extract (OE) on inflammation in mice and to elucidate its underlying mechanism. METHOD: Forty male Kunming (KM) mice were categorized into four groups: the control (CON) group, the lipopolysaccharide stimulation (LPS) group, the 5 mg mL−1 OE intervention (LPS + OE) group, and the 5 mg mL−1 OE supplementation plus mixed antibiotics (LPS + OE + ABX) group. RESULTS: The results showed that, compared with the OE group, the expression of inflammatory signaling pathway genes was upregulated and gut barrier genes were inhibited in the OE + ABX group. The Fxr receptor was activated and the abundance of Akkermansia was increased after OE supplementation, whereas the effect was reversed in the OE + ABX group. Meanwhile, Fxr was correlated positively with Akkermansia. CONCLUSION: The OE supplementation alleviated the inflammatory response in mice under LPS stimulation, accompanied by changes in gut microbiota and bile acid receptors, whereas the addition of antibiotics caused a disturbance to the gut microbiota in the OE group, thus reducing the effect of OE in alleviating the inflammatory response. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background/Objectives: Agriophyllum squarrosum (L.) Moq. (A. squarrosum), also known as sandrice, is an important medicinal plant widely distributed in dunes across all the deserts of China. Common garden trials have shown content variations in flavonoids among the ecotypes of sandrice, which correlated with temperature heterogeneity in situ. However, there have not been any environmental control experiments to further elucidate whether the accumulation of flavonoids was triggered by cold stress; Methods: This study conducted a four-day ambient 4 °C low-temperature treatment on three ecotypes along with an in situ annual mean temperature gradient (Dulan (DL), Aerxiang (AEX), and Dengkou (DK)); Results: Target metabolomics showed that 12 out of 14 flavonoids in sandrice were driven by cold stress. Among them, several flavonoids were significantly up-regulated, such as naringenin and naringenin chalcone in all three ecotypes; isorhamnetin, quercetin, dihydroquercetin, and kaempferol in DL and AEX; and astragalin in DK. They were accompanied by 19 structural genes of flavonoid synthesis and 33 transcription factors were markedly triggered by cold stress in sandrice. The upstream genes, AsqAEX006535−CHS, AsqAEX016074−C4H, and AsqAEX004011−4CL, were highly correlated with the enrichment of naringenin, which could be fine-tuned by AsqAEX015868−bHLH62, AsqAEX001711−MYB12, and AsqAEX002220−MYB1R1; Conclusions: This study sheds light on how desert plants like sandrice adapt to cold stress by relying on a unique flavonoid biosynthesis mechanism that regulating the accumulation of naringenin. It also supports the precise development of sandrice for the medicinal industry. Specifically, quercetin and isorhamnetin should be targeted for development in DL and AEX, while astragalin should be precisely developed in DK. [ABSTRACT FROM AUTHOR]

The northern South China Sea, including the Zhujiangkou Basin and the Beibuwan Basin, developed high-quality lacustrine source rocks during the Eocene rifting period. These source rocks are vital for hydrocarbon generation in the northern South China Sea. The Zhu I depression in the Zhujiangkou Basin and the Beibuwan Basin typically exhibit high abundance of C30 4-methyl steranes. However, shales in the Eocene Wenchang Formation in the Zhu III depression of the Zhujiangkou Basin contains lower quantities of high-quality lacustrine source rocks with 4-methyl steranes, which often co-elute with some pentacyclic triterpanes in gas chromatography-mass spectrometry (GC-MS). Therefore, the single 4-methylsterane parameter based on GC-MS cannot accurately distinguish organic source in the deep to semi-deep water lacustrine source rocks of the Wenchang Formation from other source rocks, thus impeding the recognition of their contributions to petroleum reservoirs. In this study, GC-MS of aliphatic hydrocarbons, palynofacies and algal identification, as well as stable carbon isotope data of organic matter were used to identify the algal species and construct the paleoclimate during deposition of the Wenchang Formation source rocks in the Zhu III depression of the Zhujiangkou Basin. It is suggested that during the Wenchang Formation period, freshwater green algae prevailed in the lake, which is likely account for the relatively low content of 4-methyl steranes in the high-quality lacustrine source rocks. Controlled by the algal species, it is proposed that the content of C30 tetracyclic polyprenoids (TPP) can better indicate the quality of the Wenchang source rocks than C30 4-methyl steranes. Consequently, a relationship between the TPP index and the quality of the lacustrine source rocks in the Wenchang Formation of the Zhu III depression was established. A higher TPP index indicates higher organic matter abundance and hydrogen index of the lacustrine source rocks. When applied to the origin analysis of oils in the Zhu III depression, it is believed that the organic-rich deep lacustrine source rocks in the Wenchang Formation made great contribution to the transitional zone crude oils in the Wenchang A and Wenchang B depressions. [ABSTRACT FROM AUTHOR]

Actinobacteria produce numerous antibiotics and other specialized metabolites that have important applications in medicine and agriculture.sup.1. Diffusible hormones frequently control the production of such metabolites by binding TetR family transcriptional repressors (TFTRs), but the molecular basis for this remains unclear.sup.2. The production of methylenomycin antibiotics in Streptomyces coelicolor A3(2) is initiated by the binding of 2-alkyl-4-hydroxymethylfuran-3-carboxylic acid (AHFCA) hormones to the TFTR MmfR.sup.3. Here we report the X-ray crystal structure of an MmfR-AHFCA complex, establishing the structural basis for hormone recognition. We also elucidate the mechanism for DNA release upon hormone binding through the single-particle cryo-electron microscopy structure of an MmfR-operator complex. DNA binding and release assays with MmfR mutants and synthetic AHFCA analogues define the role of individual amino acid residues and hormone functional groups in ligand recognition and DNA release. These findings will facilitate the exploitation of actinobacterial hormones and their associated TFTRs in synthetic biology and in the discovery of new antibiotics. X-ray crystallography and cryo-electron microscopy structures of the transcriptional repressor of the methylomycin gene cluster, MmfR, reveal the molecular basis for regulation of antibiotic biosynthesis by AHFCA hormones in Actinobacteria., Author(s): Shanshan Zhou [sup.1] , Hussain Bhukya [sup.4] , Nicolas Malet [sup.1] , Peter J. Harrison [sup.1] , Dean Rea [sup.2] , Matthew J. Belousoff [sup.5] , Hariprasad Venugopal [sup.6] [...]