Evaluating the Clinical Utility of Semi-Quantitative Luciferase Immunosorbent Assay Using Treponema pallidum Antigens in Syphilis Diagnosis and Treatment Monitoring.

OBJECTIVE: To assess the clinical applicability of a semi-quantitative luciferase immunosorbent assay (LISA) for detecting antibodies against Treponema pallidum antigens TP0171 (TP15), TP0435 (TP17), and TP0574 (TP47) in diagnosing and monitoring syphilis. METHOD: LISA for detection of anti-TP15, TP17, and TP47 antibodies was developed and evaluated for syphilis diagnosis using 261 serum samples (161 syphilis, 100 non-syphilis). 90 serial serum samples from six syphilis rabbit models (three treated, three untreated) and 110 paired serum samples from 55 syphilis patients were used to assess treatment effects by utilizing TRUST as reference. RESULTS: Compared to TPPA, LISA-TP15, LISA-TP17, and LISA-TP47 showed sensitivity of 91.9%, 96.9%, and 98.8%, specificity of 99%, 99%, and 98%, and AUC of 0.971, 0.992, and 0.995, respectively, in diagnosing syphilis. Strong correlations (rs = 0.89-0.93) with TPPA were observed. In serial serum samples from rabbit models, significant difference in the relative light unit (RLU) were observed between the treatment and control group for LISA-TP17 (days 31-51) and LISA-TP47 (days 41). In paired serum samples form syphilis patients, TRUST titers and the RLU of LISA-TP15, LISA-TP17, and LISA-TP47 decreased post treatment (P < 0.001). When TRUST titers decreased by 0, 2, 4, or ≥8-folds, the RLU decreased by 17.53%, 31.34%, 48.62%, and 72.79% for LISA-TP15; 8.84%, 17.00%, 28.37%, and 50.57% for LISA-TP17; 22.25%, 29.79%, 51.75%, and 70.28% for LISA-TP47, respectively. CONCLUSION: Semi-quantitative LISA performs well for syphilis diagnosis while LISA-TP17 is more effective for monitoring syphilis treatment in rabbit models and clinical patients.

Neuropeptides affecting social behavior in mammals: oxytocin.

Oxytocin (OXT), a neuropeptide consisting of only nine amino acids, is synthesized in the paraventricular and supraoptic nuclei of the hypothalamus. Although OXT is best known for its role in lactation and parturition, recent research has shown that it also has a significant impact on social behaviors in mammals. However, a comprehensive review of this topic is still lacking. In this paper, we systematically reviewed the effects of OXT on social behavior in mammals. These effects of OXT from the perspective of five key behavioral dimensions were summarized: parental behavior, anxiety, aggression, attachment, and empathy. To date, researchers have agreed that OXT plays a positive regulatory role in a wide range of social behaviors, but there have been controversially reported results. In this review, we have provided a detailed panorama of the role of OXT in social behavior and, for the first time, delved into the underlying regulatory mechanisms, which may help better understand the multifaceted role of OXT. Levels of OXT in previous human studies were also summarized to provide insights for diagnosis of mental disorders.

Advancing the utilization of real-world data and real-world evidence in clinical pharmacology and translational research-Proceedings from the ASCPT 2023 preconference workshop.

Real-world data (RWD) and real-world evidence (RWE) are now being routinely used in epidemiology, clinical practice, and post-approval regulatory decisions. Despite the increasing utility of the methodology and new regulatory guidelines in recent years, there remains a lack of awareness of how this approach can be applied in clinical pharmacology and translational research settings. Therefore, the American Society of Clinical Pharmacology & Therapeutics (ASCPT) held a workshop on March 21st, 2023 entitled "Advancing the Utilization of Real-World Data (RWD) and Real-World Evidence (RWE) in Clinical Pharmacology and Translational Research." The work described herein is a summary of the workshop proceedings.

Expression profiles and gene set enrichment analysis of the transcriptomes from the cancer tissue, white adipose tissue and paracancer tissue with colorectal cancer.

Background: Colorectal cancer (CRC) is one of the most common cancers worldwide and is related to diet and obesity. Currently, crosstalk between lipid metabolism and CRC has been reported; however, the specific mechanism is not yet understood. In this study, we screened differentially expressed long non-coding RNAs (lncRNAs) and mRNAs from primary cancer, paracancer, and white adipose tissue of CRC patients. We screened and analyzed the genes differentially expressed between primary and paracancer tissue and between paracancer and white adipose tissue but not between primary and white adipose tissue. According to the results of the biological analysis, we speculated a lncRNA (MIR503HG) that may be involved in the crosstalk between CRC and lipid metabolism through exosome delivery. Methods: We screened differentially expressed long non-coding RNAs (lncRNAs) and mRNAs from primary cancer, paracancer, and white adipose tissue of CRC patients. We screened and analyzed the genes differentially expressed between primary and paracancer tissue and between paracancer and white adipose tissue but not between primary and white adipose tissue. Results: We speculated a lncRNA (MIR503HG) that may be involved in the crosstalk between CRC and lipid metabolism through exosome delivery. Conclusions: In this study, the findings raise the possibility of crosstalk between lipid metabolism and CRC through the exosomal delivery of lncRNAs.

Advanced cervix cancer patient with chemotherapy-induced grade IV myelosuppression achieved complete remission with cadonilimab: A case report.

BACKGROUND: The prognosis for patients with advanced metastatic cervix cancer (MCC) is poor, and this disease continues to pose a considerable therapeutic challenge. Despite the administration of first-line regimens consisting of cisplatin, paclitaxel, and bevacizumab, survival rates for patients with metastasis remain poor. The emergence of bispecific antibodies (BsAbs) offers a novel treatment option for patients diagnosed with MCC. CASE SUMMARY: In this report, we present a patient with MCC who was treated with cadonilimab monotherapy at a dose of 6 mg/kg every two weeks after chemotherapy was proven to be intolerable. The patient exhibited a sustained complete response for a duration of 6 months, demonstrating an optimistic outlook. CONCLUSION: This case illustrates the considerable efficacy of cadonilimab for treating advanced MCC. Therefore, BsAb therapy is a promising strategy for effectively treating patients with advanced MCC and should be considered as an option when patients are intolerant to standard chemotherapy.

Cuproptosis-related gene-located DNA methylation in lower-grade glioma: Prognosis and tumor microenvironment.

Cuproptosis a novel copper-dependent cell death modality, plays a crucial part in the oncogenesis, progression and prognosis of tumors. However, the relationships among DNA-methylation located in cuproptosis-related genes (CRGs), overall survival (OS) and the tumor microenvironment remain undefined. In this study, we systematically assessed the prognostic value of CRG-located DNA-methylation for lower-grade glioma (LGG). Clinical and molecular data were sourced from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. We employed Cox hazard regression to examine the associations between CRG-located DNA-methylation and OS, leading to the development of a prognostic signature. Kaplan-Meier survival and time-dependent receiver operating characteristic (ROC) analyses were utilized to gauge the accuracy of the signature. Gene Set Enrichment Analysis (GSEA) was applied to uncover potential biological functions of differentially expressed genes between high- and low-risk groups. A three CRG-located DNA-methylation prognostic signature was established based on TCGA database and validated in GEO dataset. The 1-year, 3-year, and 5-year area under the curve (AUC) of ROC curves in the TCGA dataset were 0.884, 0.888, and 0.859 while those in the GEO dataset were 0.943, 0.761 and 0.725, respectively. Cox-regression-analyses revealed the risk signature as an independent risk factor for LGG patients. Immunogenomic profiling suggested that the signature was associated with immune infiltration level and immune checkpoints. Functional enrichment analysis indicated differential enrichment in cell differentiation in the hindbrain, ECM receptor interactions, glycolysis and reactive oxygen species pathway across different groups. We developed and verified a novel CRG-located DNA-methylation signature to predict the prognosis in LGG patients. Our findings emphasize the potential clinical implications of CRG-located DNA-methylation indicating that it may serve as a promising therapeutic target for LGG patients.

Oxygen vacancy enhanced photocatalytic activity of Cu2O/TiO2 heterojunction.

In this study, a method was developed to create oxygen vacancies in Cu2O/TiO2 heterojunctions. By varying the amounts of ethylenediaminetetraacetic acid (EDTA), sodium citrate, and copper acetate, Cu2O/TiO2 with different Cu ratios were synthesized. Tests on CO2 photocatalytic reduction revealed that Cu2O/TiO2's performance is influenced by Cu content. The ideal Cu mass fraction in Cu2O/TiO2, determined by inductively coupled plasma (ICP), is between 0.075% and 0.55%, with the highest CO yield being 10.22 µmol g-1 h-1, significantly surpassing pure TiO2. High-resolution transmission electron microscopy and electron paramagnetic resonance studies showed optimal oxygen vacancy in the most effective heterojunction. Density functional theory (DFT) calculations indicated a 0.088 eV lower energy barrier for ∗CO2 to ∗COOH conversion in Cu2O/TiO2 with oxygen vacancy compared to TiO2, suggesting that oxygen vacancies enhance photocatalytic activity.

Survival benefits of human papillomavirus 16 infection in patients with esophageal squamous cell carcinoma undergoing chemoradiotherapy: A retrospective cohort study.

The role of human papillomavirus 16 (HPV 16) in esophageal squamous cell carcinoma (ESCC) remains uncertain. Therefore, this study aimed to investigate the prevalence of HPV 16 in patients with ESCC and its impact on theirprognosis. HPV 16 was detected using FISH, and TP53 status was evaluated via immunohistochemistry. The factors influencing prognosis were ananalyzed using the Log-rank test and Cox regression analyses. Among 178 patients with ESCC, 105 and 73 patients were categorized into concurrent chemoradiotherapy (CCRT) and postoperative chemoradiotherapy (POCRT) cohorts, respectively. Among 178 patients, 87 (48.87%) tested positive for HPV 16. Log-rank tests revealed that the overall survival (OS) of patients with ESCC who were HPV 16-positive was longer than that of those who were HPV 16-negative (median OS: 57 months vs. 27 months, p < 0.01**). HPV 16 infection and TP53 mutation status were identified as independent events. The OS of patients with mutant TP53 who were HPV 16-positive was longer than that of those who were HPV 16-negative in both CCRT and POCRT cohorts (p = 0.002** for CCRT cohorts and p = 0.0023** for POCRT cohorts). Conversely, HPV 16 infection had no effect on OS in the wild-type TP53 subgroup (p = 0.13 and 0.052 for CCRT and POCRT cohorts, respectively). As a conclusion, the positive rate of HPV 16 in ESCC in this study was 48.87% (87/178). Among the patients with ESCC who had TP53 mutation, those who were HPV 16-positive exhibited a better prognosis than those who were HPV 16-negative.

Aberrant dynamic functional network connectivity in progressive supranuclear palsy.

BACKGROUND: The clinical symptoms of progressive supranuclear palsy (PSP) may be mediated by aberrant dynamic functional network connectivity (dFNC). While earlier research has found altered functional network connections in PSP patients, the majority of those studies have concentrated on static functional connectivity. Nevertheless, in this study, we sought to evaluate the modifications in dynamic characteristics and establish the correlation between these disease-related changes and clinical variables. METHODS: In our study, we conducted a study on 53 PSP patients and 65 normal controls. Initially, we employed a group independent component analysis (ICA) to derive resting-state networks (RSNs), while employing a sliding window correlation approach to produce dFNC matrices. The K-means algorithm was used to cluster these matrices into distinct dynamic states, and then state analysis was subsequently employed to analyze the dFNC and temporal metrics between the two groups. Finally, we made a correlation analysis. RESULTS: PSP patients showed increased connectivity strength between medulla oblongata (MO) and visual network (VN) /cerebellum network (CBN) and decreased connections were found between default mode network (DMN) and VN/CBN, subcortical cortex network (SCN) and CBN. In addition, PSP patients spend less fraction time and shorter dwell time in a diffused state, especially the MO and SCN. Finally, the fraction time and mean dwell time in the distributed connectivity state (state 2) is negatively correlated with duration, bulbar and oculomotor symptoms. DISCUSSION: Our findings were that the altered connectivity was mostly concentrated in the CBN and MO. In addition, PSP patients had different temporal dynamics, which were associated with bulbar and oculomotor symptoms in PSPRS. It suggest that variations in dynamic functional network connectivity properties may represent an essential neurological mechanism in PSP.

Rewritable printing of ionic liquid nanofilm utilizing focused ion beam induced film wetting.

Manipulating liquid flow over open solid substrate at nanoscale is important for printing, sensing, and energy devices. The predominant methods of liquid maneuvering usually involve complicated surface fabrications, while recent attempts employing external stimuli face difficulties in attaining nanoscale flow control. Here we report a largely unexplored ion beam induced film wetting (IBFW) technology for open surface nanofluidics. Local electrostatic forces, which are generated by the unique charging effect of Helium focused ion beam (HFIB), induce precursor film of ionic liquid and the disjoining pressure propels and stabilizes the nanofilm with desired patterns. The IBFW technique eliminates the complicated surface fabrication procedures to achieve nanoscale flow in a controllable and rewritable manner. By combining with electrochemical deposition, various solid materials with desired patterns can be produced.

Effect of high acyl gellan gum and pH on the structural and foaming properties of heated whey protein suspensions.

Effects of association between high-acyl gellan gum and whey protein on heat-induced aggregation and foaming properties of aggregates were assessed in aqueous suspensions. Associative complexes were identified by turbidity and colloidal charge below pH 6, and a balance of charge in the complexes was achieved at pH 5 with a 5:1 protein:polysaccharide ratio. As gellan gum content increased, size of aggregates formed by heating at pH 5 decreased (>1000 nm to 200-300 nm). Microscopy showed polysaccharide chains adhered to spherical aggregates at pH 5 and 6. Gellan gum added to protein before heating did not increase foam volume yet doubled foam half-life at pH 5 when used at a 2:1 protein-to-polysaccharide ratio. Microscopy showed that protein aggregates with attached gellan gum were present in drained foams. These findings indicate that gellan gum improves foam stability of heated whey protein at pH 5 by reducing aggregate size and adhering to aggregates.

Is RNA editing truly absent in the complex thalloid liverworts (Marchantiopsida)? Evidence of extensive RNA editing from Cyathodium cavernarum.

RNA editing is a crucial modification in plants' organellar transcripts that converts cytidine to uridine (C-to-U; and sometimes uridine to cytidine) in RNA molecules. This post-transcriptional process is controlled by the PLS-class protein with a DYW domain, which belongs to the pentatricopeptide repeat (PPR) protein family. RNA editing is widespread in land plants; however, complex thalloid liverworts (Marchantiopsida) are the only group reported to lack both RNA editing and DYW-PPR protein. The liverwort Cyathodium cavernarum (Marchantiopsida, Cyathodiaceae), typically found in cave habitats, was newly found to have 129 C-to-U RNA editing sites in its chloroplast and 172 sites in its mitochondria. The Cyathodium genus, specifically C. cavernarum, has a large number of PPR editing factor genes, including 251 DYW-type PPR proteins. These DYW-type PPR proteins may be responsible for C-to-U RNA editing in C. cavernarum. Cyathodium cavernarum possesses both PPR DYW proteins and RNA editing. Our analysis suggests that the remarkable RNA editing capability of C. cavernarum may have been acquired alongside the emergence of DYW-type PPR editing factors. These findings provide insight into the evolutionary pattern of RNA editing in land plants.

TCJA-SNN: Temporal-Channel Joint Attention for Spiking Neural Networks.

Spiking neural networks (SNNs) are attracting widespread interest due to their biological plausibility, energy efficiency, and powerful spatiotemporal information representation ability. Given the critical role of attention mechanisms in enhancing neural network performance, the integration of SNNs and attention mechanisms exhibits tremendous potential to deliver energy-efficient and high-performance computing paradigms. In this article, we present a novel temporal-channel joint attention mechanism for SNNs, referred to as TCJA-SNN. The proposed TCJA-SNN framework can effectively assess the significance of spike sequence from both spatial and temporal dimensions. More specifically, our essential technical contribution lies on: 1) we employ the squeeze operation to compress the spike stream into an average matrix. Then, we leverage two local attention mechanisms based on efficient 1-D convolutions to facilitate comprehensive feature extraction at the temporal and channel levels independently and 2) we introduce the cross-convolutional fusion (CCF) layer as a novel approach to model the interdependencies between the temporal and channel scopes. This layer effectively breaks the independence of these two dimensions and enables the interaction between features. Experimental results demonstrate that the proposed TCJA-SNN outperforms the state-of-the-art (SOTA) on all standard static and neuromorphic datasets, including Fashion-MNIST, CIFAR10, CIFAR100, CIFAR10-DVS, N-Caltech 101, and DVS128 Gesture. Furthermore, we effectively apply the TCJA-SNN framework to image generation tasks by leveraging a variation autoencoder. To the best of our knowledge, this study is the first instance where the SNN-attention mechanism has been employed for high-level classification and low-level generation tasks. Our implementation codes are available at https://github.com/ridgerchu/TCJA.

Construction and characterization of an infectious cDNA clone of human rhinovirus A89.

Rhinoviruses (RVs) are major causes of the common cold and are related to severe respiratory tract diseases, leading to a considerable economic burden and impacts on public health. Available and stable viral resources of rhinoviruses for laboratory use are important for promoting studies on rhinoviruses and further vaccine or therapeutic drug development. Reverse genetic technology can be useful to produce rhinoviruses and will help to promote studies on their pathogenesis and virulence. In this study, rhinovirus A89, an RV-A species that has been found to be highly involved in hospitalization triggered by RV infections, was selected to construct an infectious clone based on its sequence as a representative. The viral mRNA produced by a T7 RNA transcript system was transfected into H1-HeLa cells, and the rescued RV-A89 viruses were harvested and confirmed by sequencing. The rescued RV-A89 induced a similar cytopathic effect (CPE) and shared almost identical growth kinetics curves with parental RV-A89. Moreover, 9A7, a prescreened monoclonal antibody against the parental RV-A89, had a good and specific reaction with the rescued RV-A89, and further characterization showed almost the same morphology and protein composition of both viruses; thus, recombinant RV-A89 with similar biological characterization and virulence to the parental virus was obtained. In summary, the infectious clone of RV-A89 was successfully established, and the development of reverse genetic technology for rhinovirus will provide a framework for further studies on rhinoviruses.

Neuroprotective effects of galectin­1 on cerebral ischemia/reperfusion injury by regulating oxidative stress.

Oxidative stress contributes to the pathology of cerebral ischemia/reperfusion (I/R) injury. Galectin-1 has shown an anti-oxidative stress effect. The present study investigated whether this anti-oxidative stress effect can account for the neuroprotective actions of galectin-1 induced by cerebral I/R injury. A cerebral I/R injury model was created in C57Bl/6 mice by transient occlusion of the middle cerebral artery, after which the mice were treated with galectin-1 for 3 days. Infarct volumes were measured. A rotarod test and neurological deficit score assessment was performed to evaluate the neurological deficits. Oxidative stress was evaluated by measuring the levels of reactive oxygen species (ROS) and lipid peroxidation malondialdehyde (MDA), while the anti-oxidative stress status was assessed by measuring molecules such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidation enzyme (GSH-Px) in the ischemic cerebral hemisphere of mice. The inflammatory cytokines, including Interleukin 1 (IL-1), IL-6 and tumor necrosis factor alpha (TNF-α) were measured, and the expression of microglia was evaluated by immunohistochemistry in the ischemic cerebral hemisphere of mice. Galectin-1 treatment ameliorated neurological deficits and reduced infarct volumes in the mice model with cerebral I/R injury. Moreover, it was demonstrated that galectin-1 can significantly alleviate cerebral I/R injury in the ischemic cerebral hemisphere by decreasing the production of ROS and MDA, but increasing the production of CAT, SOD and GSH-Px. Galectin-1 treatment decreased microglia expression, and IL-1, IL-6 and TNF-α levels in the ischemic cerebral hemisphere of mice. Galectin-1 could improve the outcome of cerebral I/R injury by alleviating oxidative stress. Moreover, the neuroprotective effect of galectin-1 in cerebral ischemia could be related to its anti-oxidative stress effect.

MFN2 suppresses the accumulation of lipid droplets and the progression of clear cell renal cell carcinoma.

Dissolving the lipid droplets in tissue section with alcohol during a hematoxylin and eosin (H&E) stain causes the tumor cells to appear like clear soap bubbles under a microscope, which is a key pathological feature of clear cell renal cell carcinoma (ccRCC). Mitochondrial dynamics have been reported to be closely associated with lipid metabolism and tumor development. However, the relationship between mitochondrial dynamics and lipid metabolism reprogramming in ccRCC remains to be further explored. We conducted bioinformatics analysis to identify key genes regulating mitochondrial dynamics differentially expressed between tumor and normal tissues and immunohistochemistry and Western blot to confirm. After the target was identified, we created stable ccRCC cell lines to test the impact of the target gene on mitochondrial morphology, tumorigenesis in culture cells and xenograft models, and profiles of lipid metabolism. It was found that mitofusin 2 (MFN2) was downregulated in ccRCC tissues and associated with poor prognosis in patients with ccRCC. MFN2 suppressed mitochondrial fragmentation, proliferation, migration, and invasion of ccRCC cells and growth of xenograft tumors. Furthermore, MFN2 impacted lipid metabolism and reduced the accumulation of lipid droplets in ccRCC cells. MFN2 suppressed disease progression and improved prognosis for patients with ccRCC possibly by interrupting cellular lipid metabolism and reducing accumulation of lipid droplets.

Dynamic cerebral blood flow assessment based on electromagnetic coupling sensing and image feature analysis.

Dynamic assessment of cerebral blood flow (CBF) is crucial for guiding personalized management and treatment strategies, and improving the prognosis of stroke. However, a safe, reliable, and effective method for dynamic CBF evaluation is currently lacking in clinical practice. In this study, we developed a CBF monitoring system utilizing electromagnetic coupling sensing (ECS). This system detects variations in brain conductivity and dielectric constant by identifying the resonant frequency (RF) in an equivalent circuit containing both magnetic induction and electrical coupling. We evaluated the performance of the system using a self-made physical model of blood vessel pulsation to test pulsatile CBF. Additionally, we recruited 29 healthy volunteers to monitor cerebral oxygen (CO), cerebral blood flow velocity (CBFV) data and RF data before and after caffeine consumption. We analyzed RF and CBFV trends during immediate responses to abnormal intracranial blood supply, induced by changes in vascular stiffness, and compared them with CO data. Furthermore, we explored a method of dynamically assessing the overall level of CBF by leveraging image feature analysis. Experimental testing substantiates that this system provides a detection range and depth enhanced by three to four times compared to conventional electromagnetic detection techniques, thereby comprehensively covering the principal intracranial blood supply areas. And the system effectively captures CBF responses under different intravascular pressure stimulations. In healthy volunteers, as cerebral vascular stiffness increases and CO decreases due to caffeine intake, the RF pulsation amplitude diminishes progressively. Upon extraction and selection of image features, widely used machine learning algorithms exhibit commendable performance in classifying overall CBF levels. These results highlight that our proposed methodology, predicated on ECS and image feature analysis, enables the capture of immediate responses of abnormal intracranial blood supply triggered by alterations in vascular stiffness. Moreover, it provides an accurate diagnosis of the overall CBF level under varying physiological conditions.

Willingness to purchase institutionalised elderly services and influencing factors among Chinese older adults: a nationwide cross-sectional study.

OBJECTIVES: In view of the serious ageing of China's population and the low desire of elderly people to purchase institutionalised elderly care services, we explored the willingness of Chinese elderly people to purchase institutionalised elderly care services and its influencing factors. DESIGN: This was a cross-sectional study. Three multivariate logistic regression analysis models of the willingness of elderly people to purchase institutionalised elderly care services were established (model 1: 'reluctance - willingness'; model 2: 'reluctance - hesitation'; and model 3: 'hesitation - willingness') to explore the factors that influence elderly people's willingness to purchase institutionalised elderly care services. SETTING: This study was based on the 2022 Psychology and Behaviour Investigation of Chinese Residents database. PARTICIPANTS: Research data from 4123 older adults who met the requirements of this study were screened from the database. RESULTS: Of the 4123 respondents, roughly equal numbers had negative and positive attitudes towards purchasing institutionalised senior care services (1125, 27.3% vs 1079, 26.2%, respectively), and 1919 (46.5%) had hesitant attitudes. The analysis of model 1 showed that medical insurance participation, the number of children and siblings, chronic diseases and per capita monthly household income had an influential effect on the willingness of elderly people to purchase institutional care. In model 2, we found that factors such as per capita monthly household income and anxiety led to hesitancy among older adults to purchase institutionalised senior care services. In model 3, we further found that social support and health literacy led to a shift from hesitation to willingness to purchase institutionalised elderly care services. CONCLUSION: The number of children, number of siblings, per capita monthly income of the family, medical insurance participation, health status, health literacy and social support were found to be the main factors influencing the purchase of institutionalised care by elderly individuals.

Characterization of potassium-solubilizing fungi, Mortierella spp., isolated from a poplar plantation rhizosphere soil.

Potassium-solubilizing microorganisms are capable of secreting acidic chemicals that dissolve and release potassium from soil minerals, thus facilitating potassium uptake by plants. In this study, three potassium-dissolving filamentous fungi were isolated from the rhizosphere soil of a poplar plantation in Jiangsu Province, China. Phylogenetic analyses based on ITS, 18 S, and 28 S showed that these three isolates were most similar to Mortierella. These strains also possessed spherical or ellipsoidal spores, produced sporangia at the hyphal tip, and formed petal-like colonies on PDA media resembling those of Mortierella species. These findings, along with further phenotypic observations, suggest that these isolates were Mortierella species. In addition, the potassium-dissolution experiment showed that strain 2K4 had a relatively high potassium-solubilizing capacity among these isolated fungi. By investigating the influences of different nutrient conditions (carbon source, nitrogen source, and inorganic salt) and initial pH values on the potassium-dissolving ability, the optimal potassium-solubilization conditions of the isolate were determined. When potassium feldspar powder was used as an insoluble potassium source, isolate 2K4 exhibited a significantly better polysaccharide aggregation ability on the formed mycelium-potassium feldspar complex. The composition and content of organic acids secreted by strain 2K4 were further detected, and the potassium-dissolution mechanism of the Mortierella species and its growth promotion effect were discussed, using maize as an example.