A nomogram for predicting adverse pathologic features in low-risk papillary thyroid microcarcinoma.

BACKGROUND: Identifying risk factors for adverse pathologic features in low-risk papillary thyroid microcarcinoma (PTMC) can provide valuable insights into the necessity of surgical or non-surgical treatment. This study aims to develop a nomogram for predicting the probability of adverse pathologic features in low-risk PTMC patients. METHODS: A total of 662 patients with low-risk PTMC who underwent thyroid surgery were retrospectively analyzed in Qilu Hospital of Shandong University from May 2019 to December 2021. Logistic regression analysis was used to determine the risk factors for adverse pathologic features, and a nomogram was constructed based on these factors. RESULTS: Most PTMC patients with these adverse pathologic features had tumor diameters greater than 0.6 cm (p < 0.05). Other factors (age, gender, family history of thyroid cancer, history of autoimmune thyroiditis, and BRAFV600E mutation) had no significant correlation with adverse pathologic features (p > 0.05 each). The nomogram was drawn to provide a quantitative and convenient tool for predicting the risk of adverse pathologic features based on age, gender, family history of thyroid cancer, autoimmune thyroiditis, tumor size, and BRAFV600E mutation in low-risk PTMC patients. The areas under curves (AUC) were 0.645 (95% CI 0.580-0.702). Additionally, decision curve analysis (DCA) and calibration curves were used to evaluate the clinical benefits of this nomogram, presenting a high net benefit. CONCLUSION: Tumor size > 0.60 cm was identified as an independent risk factor for adverse pathologic features in low-risk PTMC patients. The nomogram had a high predictive value and consistency based on these factors.

Virulence, antibiotic resistance phenotypes and molecular characterisation of Vibrio furnissii isolates from patients with diarrhoea.

BACKGROUND: Vibrio furnissii is an emerging human pathogen closely related to V. fluvialis that causes acute gastroenteritis. V. furnissii infection has been reported to be rarer than V. fluvialis, but a multi-drug resistance plasmid has recently been discovered in V. furnissii. METHODS: During daily monitoring at a general hospital in Beijing, China, seven V. furnissii strains were collected from patients aged over 14 years who presented with acute diarrhoea between April and October 2018. Genome analysis and comparison were performed for virulence and antimicrobial resistance genes, plasmids and transposon islands, together with phylogenetic analysis. Antimicrobial resistance to 19 antibiotics was investigated using the microbroth dilution method. Virulence phenotypes were investigated based on type VI secretion system (T6SS) expression and using a bacterial killing assay and a haemolysin assay. RESULTS: Phylogenetic analysis based on single-nucleotide polymorphisms revealed a closer relationship between V. furnissii and V. fluvialis than between other Vibrio spp. The seven V. furnissii isolates were in different monophyletic clades in the phylogenetic tree, suggesting that the seven cases of gastroenteritis were independent. High resistance to cefazolin, tetracycline and streptomycin was found in the V. furnissii isolates at respective rates of 100.0%, 57.1% and 42.9%, and intermediate resistance to ampicillin/sulbactam and imipenem was observed at respective rates of 85.7% and 85.7%. Of the tested strains, VFBJ02 was resistant to both imipenem and meropenem, while VFBJ01, VFBJ02, VFBJ05 and VFBJ07 were multi-drug resistant. Transposon islands containing antibiotic resistance genes were found on the multi-drug resistance plasmid in VFBJ05. Such transposon islands also occurred in VFBJ07 but were located on the chromosome. The virulence-related genes T6SS, vfh, hupO, vfp and ilpA were widespread in V. furnissii. The results of the virulence phenotype assays demonstrated that our isolated V. furnissii strains encoded an activated T6SS and grew in large colonies with strong beta-haemolysis on blood agar. CONCLUSION: This study showed that diarrhoea associated with V. furnissii occurred sporadically and was more common than expected in the summer in Beijing, China. The antibiotic resistance of V. furnissii has unique characteristics compared with that of V. fluvialis. Fluoroquinolones and third-generation cephalosporins, such as ceftazidime and doxycycline, were effective at treating V. furnissii infection. Continua laboratory-based surveillance is needed for the prevention and control of V. furnissii infection, especially the dissemination of the antibiotic resistance genes in this pathogen.

Induction of senescence upon loss of the Ash2l core subunit of H3K4 methyltransferase complexes.

Gene expression is controlled in part by post-translational modifications of core histones. Methylation of lysine 4 of histone H3 (H3K4), associated with open chromatin and gene transcription, is catalyzed by type 2 lysine methyltransferase complexes that require WDR5, RBBP5, ASH2L and DPY30 as core subunits. Ash2l is essential during embryogenesis and for maintaining adult tissues. To expand on the mechanistic understanding of Ash2l, we generated mouse embryo fibroblasts (MEFs) with conditional Ash2l alleles. Upon loss of Ash2l, methylation of H3K4 and gene expression were downregulated, which correlated with inhibition of proliferation and cell cycle progression. Moreover, we observed induction of senescence concomitant with a set of downregulated signature genes but independent of SASP. Many of the signature genes are FoxM1 responsive. Indeed, exogenous FOXM1 was sufficient to delay senescence. Thus, although the loss of Ash2l in MEFs has broad and complex consequences, a distinct set of downregulated genes promotes senescence.

The ArgR-Regulated ADI Pathway Facilitates the Survival of Vibrio fluvialis under Acidic Conditions.

Vibrio fluvialis is an emerging foodborne pathogenic bacterium that can cause severe cholera-like diarrhea and various extraintestinal infections, posing challenges to public health and food safety worldwide. The arginine deiminase (ADI) pathway plays an important role in bacterial environmental adaptation and pathogenicity. However, the biological functions and regulatory mechanisms of the pathway in V. fluvialis remain unclear. In this study, we demonstrate that L-arginine upregulates the expression of the ADI gene cluster and promotes the growth of V. fluvialis. The ADI gene cluster, which we proved to be comprised of two operons, arcD and arcACB, significantly enhances the survival of V. fluvialis in acidic environments both in vitro (in culture medium and in macrophage) and in vivo (in mice). The mRNA level and reporter gene fusion analyses revealed that ArgR, a transcriptional factor, is necessary for the activation of both arcD and arcACB transcriptions. Bioinformatic analysis predicted the existence of multiple potential ArgR binding sites at the arcD and arcACB promoter regions that were further confirmed by electrophoretic mobility shift assay, DNase I footprinting, or point mutation analyses. Together, our study provides insights into the important role of the ArgR-ADI pathway in the survival of V. fluvialis under acidic conditions and the detailed molecular mechanism. These findings will deepen our understanding of how environmental changes and gene expression interact to facilitate bacterial adaptations and virulence.

Differences of the anti-oxidative capability, GPX3, and Cu/ZnSOD expression in Hu sheep testis with different size at six-month-old.

This study aimed to investigate the differences in the anti-oxidant capabilities and related gene expressions of six-month-old Hu sheep with different testis sizes. A total of 201 Hu ram lambs were fed up to 6 months in the same environment. Based on their testis weight and sperm count, 18 individuals were selected and divided into large (n = 9) and small (n = 9) groups, with an average testis weight of 158.67 g ± 5.21 g and 44.58 g ± 4.14 g, respectively. The total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), and malondialdehyde (MDA) concentration in testis tissue were tested. The localization of antioxidant-related genes, GPX3 and Cu/ZnSOD in testis were detected by immunohistochemistry. The GPX3, Cu/ZnSOD expression, and relative mitochondrial DNA (mtDNA) copy number were detected by quantitative real-time PCR. Compared with the small group, the T-AOC (2.69 ± 0.47 vs. 1.16 ± 0.22 U/mgprot) and T-SOD (22.35 ± 2.59 vs. 9.92 ± 1.62 U/mgprot) in the large group were significantly higher, whereas the MDA (0.72 ± 0.13 vs. 1.34 ± 0.17 nM/mgprot) and relative mtDNA copy number in the large group was significantly lower (p < .05). Immunohistochemistry results indicated that the GPX3 and Cu/ZnSOD were expressed in Leydig cells and seminiferous tubule. The expressions of GPX3 and Cu/ZnSOD mRNA in the large group were significantly higher than those in the small group (p < .05). In conclusion, Cu/ZnSOD and GPX3 widely expressed in the Leydig cells and seminiferous tubule, high expression of Cu/ZnSOD and GPX3 in a large group has a higher potential in addressing oxidative stress and contribute to spermatogenesis.

A PolyQ Membrane Protein of Vibrio cholerae Acts as the Receptor for Phage Infection.

Bacteriophage VP1 is a typing phage used for the phage subtyping of Vibrio cholerae O1 biotype El Tor, but the molecular mechanisms of its receptor recognition and the resistance of its host to infection are mostly unknown. In this study, we aimed to identify the host receptor and its role in resistance in natural VP1-resistant strains. Generating spontaneous resistance mutations and genome sequencing mutant strains found the polyQ protein VcpQ, which carries 46 glutamine residues in its Q-rich region, to be responsible for infection by VP1. VcpQ is a membrane protein and possibly forms homotrimers. VP1 adsorbed to V. cholerae through VcpQ. Sequence comparisons showed that 72% of natural VP1-resistant strains have fewer glutamines in the VcpQ Q-rich stretch than VP1-sensitive strains. This difference did not affect the membrane location and oligomer of VcpQ but abrogated VP1 adsorption. These mutant VcpQs did not recover VP1 infection sensitivity in a V. cholerae strain with vcpQ deleted. Our study revealed that the polyQ protein VcpQ is responsible for the binding of VP1 during its infection of V. cholerae and that glutamine residue reduction in VcpQ affects VP1 adsorption to likely be the main cause of VP1 resistance in natural resistant strains. The physiological functions of this polyQ protein in bacteria need further clarification; however, mutations in the polyQ stretch may endow V. cholerae with phage resistance and enhance survival against VP1 or related phages.IMPORTANCE Receptor recognition and binding by bacteriophage are the first step for its infection of bacterial cells. In this study, we found the Vibrio cholerae subtyping phage VP1 uses a polyQ protein named VcpQ (V. cholerae polyQ protein) as the receptor for VP1 infection. Our study reveals the receptor's recognition of phage VP1 during its adsorption and the VP1 resistance mechanism of the wild resistant V. cholerae strains bearing the mutagenesis in the receptor VcpQ. These mutations may confer the survival advantage on these resistant strains in the environment containing VP1 or its similar phages.

vgrG is separately transcribed from hcp in T6SS orphan clusters and is under the regulation of IHF and HapR.

V. cholerae, the causative agent of cholera epidemic, and V. fluvialis, the emerging foodborne pathogen, share highly homologous T6SS consisting of one large cluster and two small orphan or auxiliary clusters, and each of which was generally recognized as one operon. Here, we showed that the genes in each of the small clusters are organized into two transcriptional units. Specifically, the inner tube coding gene hcp/tssD is highly transcribed as one monocistron, while the tip component vgrG/tssI and its downstream effector and immunity genes are in one polycistron with very low transcriptional level. This conclusion is supported by qPCR analysis of mRNA abundance, reporter fusion analysis and transcriptional unit definition with RT-PCR analysis. Taking tssI2_a of V. fluvialis as an example, we further demonstrated that quorum sensing (QS) regulator HapR and global regulator IHF activate vgrG/tssI transcription by directly binding to its promoter region. Taken together, current studies deepen our understanding of T6SS system, highlighting its regulatory complexity during functional execution process.

Response and resilience of Asian agrifood systems to COVID-19: An assessment across twenty-five countries and four regional farming and food systems.

Context: The COVID-19 pandemic has been affecting health and economies across the world, although the nature of direct and indirect effects on Asian agrifood systems and food security has not yet been well understood. Objectives: This paper assesses the initial responses of major farming and food systems to COVID-19 in 25 Asian countries, and considers the implications for resilience, food and nutrition security and recovery policies by the governments. Methods: A conceptual systems model was specified including key pathways linking the direct and indirect effects of COVID-19 to the resilience and performance of the four principal Asian farming and food systems, viz, lowland rice based; irrigated wheat based; hill mixed; and dryland mixed systems. Based on this framework, a systematic survey of 2504 key informants (4% policy makers, 6% researchers or University staff, 6% extension workers, 65% farmers, and 19% others) in 20 Asian countries was conducted and the results assessed and analysed. Results and conclusion: The principal Asian farming and food systems were moderately resilient to COVID-19, reinforced by government policies in many countries that prioritized food availability and affordability. Rural livelihoods and food security were affected primarily because of disruptions to local labour markets (especially for off-farm work), farm produce markets (notably for perishable foods) and input supply chains (i.e., seeds and fertilisers). The overall effects on system performance were most severe in the irrigated wheat based system and least severe in the hill mixed system, associated in the latter case with greater resilience and diversification and less dependence on external inputs and long market chains. Farming and food systems' resilience and sustainability are critical considerations for recovery policies and programmes, especially in relation to economic performance that initially recovered more slowly than productivity, natural resources status and social capital. Overall, the resilience of Asian farming and food systems was strong because of inherent systems characteristics reinforced by public policies that prioritized staple food production and distribution as well as complementary welfare programmes. With the substantial risks to plant- and animal-sourced food supplies from future zoonoses and the institutional vulnerabilities revealed by COVID-19, efforts to improve resilience should be central to recovery programmes. Significance: This study was the first Asia-wide systems assessment of the effects of COVID-19 on agriculture and food systems, differentiating the effects of the pandemic across the four principal regional farming and food systems in the region.

Quorum sensing regulation confronts the development of a viable but non-culturable state in Vibrio cholerae.

Vibrio cholerae can enter a viable but non-culturable (VBNC) state when it encounters unfavourable environments; VBNC cells serve as important reservoirs and still pose threats to public health. The genetic regulation of V. cholerae entering its VBNC state is not well understood. Here, we show a confrontation strategy adapted by V. cholerae O1 in which it utilizes a quorum sensing (QS) system to prevent transition into a VBNC state under low nutrition and temperature conditions. The upregulation of hapR resulted in a prolonged culturable state of V. cholerae in artificial sea water at 4°C, whereas the mutation of hapR led to fast entry into the VBNC state. We also observed that different V. cholerae O1 natural isolates with distinct QS functions present a variety of abilities to maintain culturability during the transition to a VBNC state. The strain groups with higher or constitutive expression of QS genes exhibit a greater tendency to maintain the culturable state during VBNC induction than those lacking QS functional groups. In summary, HapR-mediated QS regulation is associated with the transition to the VBNC state in V. cholerae. HapR expression causes V. cholerae to resist VBNC induction and become dominant over competitors in changing environments.

The outer-membrane protein TolC of Vibrio cholerae serves as a second cell-surface receptor for the VP3 phage.

Receptor recognition is a key step in the initiation of phage infection. Previously, we found that VP3, the T7 family phage of the Vibrio cholerae serogroup O1 biotype El Tor, can adsorb the core oligosaccharide (OS) of lipopolysaccharides of V. cholerae However, some wildtype strains of V. cholerae possessing the intact OS gene cluster still have VP3 binding but are resistant to VP3 infection. Moreover, an OS gene-deletion mutant still exhibits weak VP3 binding, suggesting multiple factors are possibly involved in VP3 binding to V. cholerae Here, we report that the outer-membrane protein TolC of V. cholerae is involved in the host adsorption of VP3. We observed that TolC directly interacts with the VP3 tail fiber protein gp44 and its C-terminal domains, and we also found that three amino acid residues in the outside loops of TolC, at positions 78, 290, and 291, are critical for binding to gp44. Among the VP3-resistant wildtype V. cholerae strains, frequent amino acid residue mutations were observed in the loops around the sites 78, 290, and 291, which were predicted to be exposed to the cell surface. These findings reveal a co-receptor-binding mechanism for VP3 infection of V. cholerae and that both outer-membrane TolC and OS are necessary for successful VP3 infection of V. cholerae We conclude that mutations on the outside loops of the receptor may confer V. cholerae strains with VP3 phage resistance, enabling these strains to survive in environments containing VP3 or related phages.

Serotype-shifting gene rfbT is a direct transcriptional target of cAMP receptor protein (CRP) in V. cholerae O1.

Ogawa and Inaba are two main serotypes of O1 V. cholerae and alternate among cholera epidemics. The rfbT gene encodes a methyltransferase and is required for Ogawa serotype. The Inaba serotype is the consequence of genetic alterations in rfbT gene which results in loss-of-function enzyme product. However, the expression and regulation of rfbT has not been understood yet. Here we demonstrated that a global regulator, cAMP receptor protein (CRP), positively regulates rfbT transcription through a non-canonical CRP binding site (CBS) in its promoter region. This finding is supported by the analyses of rfbT mRNA abundance, rfbT-lacZ fusions and electrophoretic mobility shift assay (EMSA). The analyses of rfbT mRNA level in wild type (WT), Δcrp, and lower or higher level of cAMP backgrounds revealed that CRP is required for rfbT expression in response to intracellular cAMP level. Subsequent rfbT-lacZ fusions and EMSA collectively displayed that cAMP-CRP complex transcriptionally activates rfbT through directly binding to CBS in rfbT promoter region. Consistently, serological microagglutination test showed that crp deletion resulted in at least 4-fold decrease in titer of Ogawa serum compared to its WT. These results expanded our knowledge of understanding the genetic determinants and probable regulatory mechanism of V. cholerae O1 serotype shift between Ogawa and Inaba.

Scope for improved eco-efficiency varies among diverse cropping systems.

Global food security requires eco-efficient agriculture to produce the required food and fiber products concomitant with ecologically efficient use of resources. This eco-efficiency concept is used to diagnose the state of agricultural production in China (irrigated wheat-maize double-cropping systems), Zimbabwe (rainfed maize systems), and Australia (rainfed wheat systems). More than 3,000 surveyed crop yields in these three countries were compared against simulated grain yields at farmer-specified levels of nitrogen (N) input. Many Australian commercial wheat farmers are both close to existing production frontiers and gain little prospective return from increasing their N input. Significant losses of N from their systems, either as nitrous oxide emissions or as nitrate leached from the soil profile, are infrequent and at low intensities relative to their level of grain production. These Australian farmers operate close to eco-efficient frontiers in regard to N, and so innovations in technologies and practices are essential to increasing their production without added economic or environmental risks. In contrast, many Chinese farmers can reduce N input without sacrificing production through more efficient use of their fertilizer input. In fact, there are real prospects for the double-cropping systems on the North China Plain to achieve both production increases and reduced environmental risks. Zimbabwean farmers have the opportunity for significant production increases by both improving their technical efficiency and increasing their level of input; however, doing so will require improved management expertise and greater access to institutional support for addressing the higher risks. This paper shows that pathways for achieving improved eco-efficiency will differ among diverse cropping systems.

Diagnostic Values of Carcinoembryonic Antigen, Cancer Antigen 15-3 and Cancer Antigen 125 Levels in Nipple Discharge.

An expedient and cost-effective diagnostic tool is needed to complement galactography and exfoliative cytology for detection of benign or malignant breast diseases with nipple discharge. The aim of this prospective study is to explore the utility of carcinoembryonic antigen, cancer antigen 15-3 and cancer antigen 125 levels in nipple discharge for the diagnosis of various breast diseases. We evaluated the pre-operative tumor marker levels in 153 nipple discharge samples collected from one or both breasts of 142 women undergoing surgery. Patients with nipple discharge underwent auxiliary examination (ultrasonography, exfoliative cytology, ductoscopy and galactography). Statistically higher levels of carcinoembryonic antigen and cancer antigen 15-3 were found in patients in the malignant group as compared to those in the benign group. No statistically significant difference in the level of cancer antigen 125 (P = 0.895). Sensitivities of carcinoembryonic antigen and cancer antigen 15-3 for diagnosing breast cancer were 74.42% and 58.14%, and specificities were 87.27% and 80.00% where as the cutoff values with max-sum of sensitivity and specificity were 224.3 ng/ml and 1368.2 U/ml, respectively. The following sensitivities for telling malignant from benign could be determined: exfoliative cytology 46.67%, ultrasonography 76.74%, galactography 75.00%, and ductoscopy 0%. Exfoliative cytology was found to be a valuable alternative method for differentiating benign from malignancy. Thus, tumor marker analysis of nipple discharge fluid for carcinoembryonic antigen and cancer antigen 15-3 would enhance the accurate assessment and treatment planning for patients with nipple discharge.

The seventh pandemic Vibrio cholerae O1 El Tor isolate in China has undergone genetic shifts.

A total of 330 clinical Vibrio cholerae O1 serogroups from China dating between 1961 and 2010 were investigated. By phenotypic biotyping and genetic analysis, during the seventh pandemic of V. cholerae O1 in China, the isolates of hybrid biotype (mixed classical phenotypes) were present during the entire1961-2010 period, while El Tor genetic shifts appeared in 1992 and replaced the prototype El Tor from 2002 to 2010.

Identification of genetic bases of vibrio fluvialis species-specific biochemical pathways and potential virulence factors by comparative genomic analysis.

Vibrio fluvialis is an important food-borne pathogen that causes diarrheal illness and sometimes extraintestinal infections in humans. In this study, we sequenced the genome of a clinical V. fluvialis strain and determined its phylogenetic relationships with other Vibrio species by comparative genomic analysis. We found that the closest relationship was between V. fluvialis and V. furnissii, followed by those with V. cholerae and V. mimicus. Moreover, based on genome comparisons and gene complementation experiments, we revealed genetic mechanisms of the biochemical tests that differentiate V. fluvialis from closely related species. Importantly, we identified a variety of genes encoding potential virulence factors, including multiple hemolysins, transcriptional regulators, and environmental survival and adaptation apparatuses, and the type VI secretion system, which is indicative of complex regulatory pathways modulating pathogenesis in this organism. The availability of V. fluvialis genome sequences may promote our understanding of pathogenic mechanisms for this emerging pathogen.

[The study of ctxB and rstR variations of toxigenic Vibrio cholerae O1 El Tor strains isolated from 1961 to 2010 in China].

OBJECTIVE: To understand the ctxB and rstR variations of toxigenic Vibrio cholerae (V.cholerae) O1 El Tor strains isolated from different provinces in China from 1961 to 2010. METHODS: All 385 toxigenic V.cholerae O1 El Tor strains were selected, which were isolated in China between year 1961 and 2010. ctxB gene was amplified by PCR method and sequenced for further analysis. rstR was detected with PCR by using the genotype specific primers. RESULTS: ctxB sequence analysis revealed that 52.5% (202/385) isolates carried ctxB(ET) and 47.5% (183/385) carried ctxB(class), namely Y(39) to H and I(68) to T substitutions which were specific to the classical biotype CT-B sequence. From 1961 to 1992, strains carrying ctxB(ET) were predominant and the proportion was as high as 98.4% (182/185). After 1993, strains carrying ctxB(class) were sharply increased. Especially during year 1993 to year 2005, 97.2% (174/179) of the isolated strains carried ctxB(class). Since 2006, resurgence of dominant strains carrying ctxB(ET) or co-existing of strains with ctxB(ET) or ctxB(class) was noticed. rstR genotype detection showed that 62.9% (242/385)of the tested strains carried the rstR(ET), while 6.8% (26/385) with rstR(class), and the remainings contained at least two types of rstR in different combination forms, among which rstR(ET)+rstR(class) combination were the most, accounting for 75.7% (75/99) . Similar to the ctxB, the distribution of rstR genotypes showed time specificity. From 1961 to 1992, strains carrying rstR(ET) predominated (87.0%, 161/185). After 1993, the diversity of rstR genotypes was observed accompanying by a sharp increase of strains containing other rstR genotype, such as rstR(class), rstR(env) and different combinations. There were separately 96% (25/26), 84% (63/75) and 18/18 strains containing rstR(class), rstR(ET)+rstR(class) and rstR(ET)+rstR(class)+rstR(env) isolated after 1993. CONCLUSION: The distribution of different genotypes of ctxB and rstR showed obvious time-specificity, and there were various combining forms of rstR, reflecting the diversity of the genetic and evolutionary characteristics of Chinese V.cholerae isolates.

Characterization of Quorum regulatory small RNAs in an emerging pathogen Vibrio fluvialis and their roles toward type VI secretion system VflT6SS2 modulation.

AbstractThe type VI secretion system (T6SS) is essential for Gram-negative bacteria to antagonize a wide variety of prokaryotic and eukaryotic competitors and thus gain survival advantages. Two sets of T6SS have been found in Vibrio fluvialis, namely VflT6SS1 and VflT6SS2, among which VflT6SS2 is functionally expressed. The CqsA/LuxS-HapR quorum sensing (QS) system with CAI-1 and AI-2 as signal molecules can regulate VflT6SS2 by regulators LuxO and HapR, with LuxO repressing while HapR activating VflT6SS2. Quorum regulatory small RNAs (Qrr sRNAs) are Hfq-dependent trans-encoded sRNAs that control Vibrio quorum sensing. In V. fluvialis, Qrr sRNAs have not been characterized and their regulatory function were unknown. In this study, we first identified four Qrr sRNAs in V. fluvialis and demonstrated that these Qrr sRNAs are regulated by LuxO and involved in the modulation of VflT6SS2 function. On the one hand, Qrr sRNAs act on HapR, the activator of both the major and the auxiliary clusters of VflT6SS2, and then indirectly repress VflT6SS2. On the other hand, they directly repress VflT6SS2 by acting on tssB2 and tssD2_a, the first gene of the major cluster and the highly transcriptional one among the two units of the first auxiliary cluster, respectively. Our results give insights into the role of Qrr sRNAs in CAI-1/AI-2 based QS and VflT6SS2 modulation in V. fluvialis and further enhance understandings of the network between QS and T6SS regulation in Vibrio species.

Localization and expression of phospholipase A2 and polyunsaturated fatty acid profile in the testis tissues of Hu sheep.

The fatty acid content and the localization and expression of phospholipase A2 (PLA2) in the testis of Hu sheep were investigated. A total of 18 six-month-old Hu sheep were divided into small group (S, with left testis weight < 50 g), medium group (M, with left testis weight among 90-110 g), and large group (L, with left testis weight >160 g), which had six individuals each. The expression of PLA2 in testicular tissues of different sizes was analyzed by immunohistochemistry, RT-qPCR, and Western blot. The fatty acid profile was detected by gas chromatography. Immunohistochemical labeling determined that PLA2 protein was expressed in the Leydig and Sertoli cells of testis, and the immunohistochemical average optional density in the S group was significantly greater than the L group (P < 0.05). RT-qPCR and Western blot analysis showed that PLA2 in the S group was greater than that in the L group (P < 0.05). Docosahexaenoic acid, ω-3 polyunsaturated fatty acid (PUFA), and total PUFA content in the testis of the L group were significantly less than those of the S and M groups (P < 0.01). This study showed that PLA2 content in the S group was greater than that in the L group.

Optical vectorial-mode parity Hall effect: a case study with cylindrical vector beams.

The vectorial optical field (VOF) assumes a pivotal role in light-matter interactions. Beyond its inherent polarization topology, the VOF also encompasses an intrinsic degree of freedom associated with parity (even or odd), corresponding to a pair of degenerate orthogonal modes. However, previous research has not delved into the simultaneous manipulation of both even and odd parities. In this study, we introduce and validate the previously unexplored parity Hall effect for vectorial modes using a metasurface design. Our focus lies on a cylindrical vector beam (CVB) as a representative case. Through the tailored metasurface, we effectively separate two degenerate CVBs with distinct parities in divergent directions, akin to the observed spin states split in the spin Hall effect. Additionally, we provide experimental evidence showcasing the capabilities of this effect in multi-order CVB demultiplexing and parity-demultiplexed CVB-encoded holography. This effect unveils promising opportunities for various applications, including optical communication and imaging.

The Prevalence of Rickettsial and Rickettsial-Like Diseases in Patients with Undifferentiated Febrile Illness - Hainan Province, China, 2018-2021.

Introduction: Rickettsial and Rickettsial-like diseases, resulting from obligate intracellular Gram-negative bacteria, pose a growing public health threat in China. To assess the current prevalence of these diseases on Hainan Island, a study was conducted on 9 bacterial pathogens found in patients with undifferentiated febrile illness (UFI) treated in Haikou between 2018 and 2021 using a TaqMan Polymerase Chain Reaction (TaqMan PCR) array. Methods: Blood samples (n=503) were collected from patients with UFI between 2018 and 2021. The samples were screened for Rickettsia spp., Orientia tsutsugamushi (O. tsutsugamushi), Anaplasma. phagocytophilum (A. phagocytophilum), Ehrlichia chaffeensis, Coxiella burnetii, Chlamydia psittaci, Brucella spp., Burkholderia pseudomallei, and Borrelia burgdorferi using a TaqMan PCR array. Positive samples (Ct<35) underwent confirmation through nested PCR, sequencing, and phylogenetic analysis. Results: O. tsutsugamushi and A. phagocytophilum were detected in the patients at positive rates of 14.51% (73/503) and 5.57% (28/503), respectively. Co-infection of O. tsutsugamushi and A. phagocytophilum was identified in scrub typhus (ST) positive populations from Hainan (10.96%, 8/73), Guangxi (61.54%, 8/13), and Yunnan (5.36%, 3/56) provincial-level administrative divisions (PLADs) of China. Conclusion: An increased prevalence rate of ST and a decreased prevalence of rickettsioses were observed in patients with UFI in Hainan compared to a decade ago. The co-infection of O. tsutsugamushi and A. phagocytophilum poses a current public health threat in China.