Enhanced VEGF secretion and blood-brain barrier disruption: Radiation-mediated inhibition of astrocyte autophagy via PI3K-AKT pathway activation.

Radiation-induced damage to the blood-brain barrier (BBB) is the recognized pathological basis of radiation-induced brain injury (RBI), a side effect of head and neck cancer treatments. There is currently a lack of therapeutic approaches for RBI due to the ambiguity of its underlying mechanisms. Therefore, it is essential to identify these mechanisms in order to prevent RBI or provide early interventions. One crucial factor contributing to BBB disruption is the radiation-induced activation of astrocytes and oversecretion of vascular endothelial growth factor (VEGF). Mechanistically, the PI3K-AKT pathway can inhibit cellular autophagy, leading to pathological cell aggregation. Moreover, it acts as an upstream pathway of VEGF. In this study, we observed the upregulation of the PI3K-AKT pathway in irradiated cultured astrocytes through bioinformatics analysis, we then validated these findings in animal brains and in vitro astrocytes following radiation exposure. Additionally, we also found the inhibition of autophagy and the oversecretion of VEGF in irradiated astrocytes. By inhibiting the PI3K-AKT pathway or promoting cellular autophagy, we observed a significant amelioration of the inhibitory effect on autophagy, leading to reductions in VEGF oversecretion and BBB disruption. In conclusion, our study suggests that radiation can inhibit autophagy and promote VEGF oversecretion by upregulating the PI3K-AKT pathway in astrocytes. Blocking the PI3K pathway can alleviate both of these effects, thereby mitigating damage to the BBB in patients undergoing radiation treatment.

The impact of nurses' experiences of hospital violence on resilience: A mediated moderation model.

AIMS: This study aims to investigate the impact of nurses' experiences of hospital violence on resilience, the mediating effect of trust in patients and the moderating effect of organizational trust. BACKGROUND: Despite belonging to the central part of health care worldwide and being the leading provider of medical services, nurses are often subjected to hospital violence, which affects their physical and mental well-being. Trust is a high-order mechanism that encourages positive thinking and personal and professional development. However, research into the impact of trust on resilience concerning nurses' experiences of hospital violence is limited. METHODS: The participants were 2331 nurses working in general hospitals in China. A cross-sectional survey was conducted, and data were collected via questionnaires from July to October 2022 and analysed using SPSS 25.0 and SPSS PROCESS 3.3 macros. This study was prepared and reported according to the STROBE checklist. RESULTS: Mean trust in patients was 48.00 ± 10.86 (12-60), mean organizational trust was 56.19 ± 8.90 (13-65) and mean resilience was 78.63 ± 19.26 (0-100). Nurses' experience of hospital violence had a direct negative effect on resilience (ß = -.096, p = .871), a significant adverse effect on trust in patients (ß = -3.022, p < .001) and a significant positive effect on trust in patients on resilience (ß = 1.464, p < .001). Trusting patients played a mediating role. The significant moderating effect of organizational trust between experience of hospital violence and trust in patients was moderated by a mediating effect index of -0.1867 (95% CI = [-0.3408, -0.0345]). CONCLUSIONS: Nurses' experience of hospital violence exerted a negative effect on resilience, trust in patients had a fully mediated effect and organizational trust had a significant moderating influence in the pathway from nurses' experience of hospital violence to patients' trust-mediated resilience. IMPLICATIONS FOR NURSING AND HEALTH POLICY: This study highlights the impact of nurses' experiences of hospital violence on resilience and explores the importance of trust from the nurses' perspective. Measures taken by managers to provide nurses with a safe, trusting and positive work environment can be highly beneficial in enhancing nurse resilience.

Clinical nurse adherence to professional ethics: A grounded theory.

BACKGROUND: Professional ethics is the regulation and discipline of nurses' daily nursing work. Nurses often encounter various ethical challenges and problems in their clinical work, but there are few studies on nurses' adherence to professional ethics. RESEARCH AIM: An analysis of nursing adherence to nursing ethics from the perspective of clinical nurses in the Chinese public health system. RESEARCH DESIGN: This study adopts the grounded theory approach proposed by Strauss and Corbin. PARTICIPANTS AND RESEARCH CONTEXT: Between July 2021 and January 2022, Clinical nurses were recruited for online video interviews using purposive and theoretical sampling methods in seven hospitals in Beijing, Tianjin, Shanxi, Henan, Guangdong, and Fujian, China. Data analysis was conducted using Strauss and Corbin's coding approach. ETHICAL CONSIDERATIONS: This study was approved by the Ethics Committee of Sanming First Hospital (MingYiLun 71/2021). FINDINGS: A total of 27 participants were included. A theoretical model of nursing staff adherence to professional ethics was constructed. The main core was adherence to professional ethics and the other cores were (1) causal conditions: professional ethics code, individual conscience; (2) intervening conditions: personal growth, social support system, matching career compensation, prediction of adverse consequences; (3) action strategies: sticking to professional values, self-regulation, flexible response, post-event improvement; and (4) outcomes: self-harmony, reduced medical disputes. CONCLUSIONS: This study provides an interpretive understanding of why clinical nurses adhere to professional ethics in China and describes the challenges and issues posed by nurses' use of strategies to cope with ethical adversity. The findings can be used to develop future complex studies.

The impact of resilience on clinical nurses' moral courage during COVID-19: A moderated mediation model of ethical climate and moral distress.

AIM: The purpose of this study was to explore whether clinical ethical climate mediates the relationship between resilience and moral courage in a population of clinical nurses during COVID-19, and if moral distress faced by nurses is a moderating factor. BACKGROUND: Resilience can help nurses maintain their personal health during COVID-19 when they face great physical and psychological shock and are prone to health problems. Moral courage, as an ethical competency, helps nursing staff in adhering to the principles and values of professional ethics. There is a strong correlation between resilience and moral courage, but the mechanism by which resilience contributes to moral courage is unclear. METHOD: A cross-sectional study research is designed. Three hundred thirty clinical nurses from six hospitals in Beijing, Sichuan, and Fujian of China were included between August 2021 and March 2022. The survey instruments include the Nurses' Moral Courage Scale (NMCS), Connor-Davidson Resilience Scale (CD-RISC), Moral Distress Scale-Revised (MDS-R), and Hospital Ethical Climate Scale (HECS). RESULTS: Ethical climate mediates 15% of the relationship between resilience and moral courage. The association between resilience and ethical climate, as well as the indirect relationship between resilience and moral courage, was modified by moral distress. DISCUSSION: This study investigated the mechanisms by which resilience affects moral courage in clinical nurses in the context of COVID-19, suggesting that moral courage can be increased by alleviating moral distress and increasing ethical climate. IMPLICATIONS FOR NURSING AND HEALTH POLICY: This study confirms the mediating effect of moral climate on the relationship between resilience and moral courage, as well as the moderating effect of moral distress. Hospital policymakers should value nurses' psychological resilience and moral courage, develop effective policies to prevent and manage stressors, build social support systems, and create a positive ethical climate.

Perceptions of pelvic floor dysfunction and rehabilitation care amongst women in southeast China after radical hysterectomy: a qualitative study.

OBJECTIVE: To investigate the perceptions of pelvic floor dysfunction (PFD) and rehabilitation care amongst women after radical hysterectomy and to explore ways to improve quality of care. METHODS: Thirty-six women who underwent radical hysterectomy at a hospital in southeast China were enrolled via purposive sampling. Semi-structured in-depth interviews were conducted. The texts were analysed via qualitative content analysis. RESULTS: Four themes were obtained: serious lack of knowledge, heavy psychological burden, different coping strategies and great eagerness to receive multiparty support on PFD rehabilitation care. CONCLUSION: The society and professional staff should strengthen health education on PFD. Professionals should offer education before and after surgery and actively provide rehabilitation consultation to promote the availability of rehabilitation to support women with PFD rehabilitation care. In addition, family-centred care is an important way to support women to return to normal life, and women's need for family support should be more actively expressed. Moreover, knowledge of medical insurance should be popularised, especially in rural areas in China.

Reliability and validity of the Mandarin version of the Trust in Nurses Scale.

AIMS: This study aimed to translate and validate the Trust in Nurses Scale (TINS) and then test and implement the tool. BACKGROUND: Trust is the core feature of the nurse-patient relationship, and a simple and universal instrument to measure patients' trust in nurses in China is lacking. METHODS: Exploratory and confirmatory factor analyses (EFA and CFA) were performed to verify structural validity. Content validity and reliability analyses were also conducted. RESULTS: The Cronbach's alpha of the TINS was .817, and the test-retest reliability coefficient was .852. EFA revealed two factors and explained 59.702% of the total variation. CFA proved that all the goodness-of-fit indicators were acceptable. CONCLUSION: The TINS exhibited satisfactory reliability and validity, and it can be universally applied to survey Chinese patients' trust in nurses. IMPLICATIONS FOR NURSING MANAGEMENT: The TINS can be used by nursing managers to assess patients' trust in nurses, and appropriate programmes can be developed to improve patients' trust.

Design, synthesis, biological evaluation and molecular dynamics simulation studies of imidazolidine-2,4-dione derivatives as novel PTP1B inhibitors.

Protein tyrosine phosphatase 1B (PTP1B) is a member of the phosphotyrosine phosphatase family and plays an important role in the signal transduction of diabetes. Inhibition of PTP1B activity can increase insulin sensitivity and reduce blood sugar levels. Therefore, it is urgent to find compounds with novel structures that can inhibit PTP1B. This study designed imidazolidine-2,4-dione derivatives through the computer-aided drug design (CADD) strategy, and the Comp#10 showed outstanding inhibitory ability. (IC50 = 2.07 µM) and selectivity. The inhibitory mechanism at molecular level of Comp#10 on PTP1B was studied by molecular dynamics simulation. The results show that the catalytic region of PTP1B protein is more stable, which makes the catalytic sites unsuitable for exposure. Interestingly, the most obvious changes in the interaction between residues in the P-loop region (such as: His214, Cys215, and Ser216). In short, this study reported for the first time that imidazolidine-2,4-dione derivatives as novel PTP1B inhibitors had good inhibitory activity and selectivity, providing new ideas for the development of small molecule PTP1B inhibitors.

Comparative genomics and transcriptomics analyses provide insights into the high yield and regulatory mechanism of Norvancomycin biosynthesis in Amycolatopsis orientalis NCPC 2-48.

BACKGROUND: Norvancomycin has been widely used in clinic to treat against MRSA (Methicillin-resistant Staphylococcus aureus) and MRSE (Methicillin-resistant Staphylococcus epidermidis) infections in China. Amycolatopsis orientalis NCPC 2-48, a high yield strain derived from A. orientalis CPCC 200066, has been applied in industrial large-scale production of norvancomycin by North China Pharmaceutical Group. However, the potential high-yield and regulatory mechanism involved in norvancomycin biosynthetic pathway has not yet been addressed. RESULTS: Here we sequenced and compared the genomes and transcriptomes of A. orientalis CPCC 200066 and NCPC 2-48. These two genomes are extremely similar with an identity of more than 99.9%, and no duplication and structural variation was found in the norvancomycin biosynthetic gene cluster. Comparative transcriptomic analysis indicated that biosynthetic genes of norvancomycin, as well as some primary metabolite pathways for the biosynthetic precursors of norvancomycin were generally upregulated. AoStrR1 and AoLuxR1, two cluster-situated regulatory genes in norvancomycin cluster, were 23.3-fold and 5.8-fold upregulated in the high yield strain at 48 h, respectively. Over-expression of AoStrR1 and AoLuxR1 in CPCC 200066 resulted in an increase of norvancomycin production, indicating their positive roles in norvancomycin biosynthesis. Furthermore, AoStrR1 can regulate the production of norvancomycin by directly interacting with at least 8 promoters of norvancomycin biosynthetic genes or operons. CONCLUSION: Our results suggested that the high yield of NCPC 2-48 can be ascribed to increased expression level of norvancomycin biosynthetic genes in its cluster as well as the genes responsible for the supply of its precursors. The norvancomycin biosynthetic genes are presumably regulated by AoStrR1 and AoLuxR1, of them AoStrR1 is possibly the ultimate pathway-specific regulator for the norvancomycin production. These results are helpful for further clarification of the holistic and pathway-specific regulatory mechanism of norvancomycin biosynthesis in the industrial production strain.

Inducing secondary metabolite production of Aspergillus sydowii through microbial co-culture with Bacillus subtilis.

BACKGROUND: The co-culture strategy which mimics natural ecology by constructing an artificial microbial community is a useful tool to activate the biosynthetic gene clusters to generate new metabolites. However, the conventional method to study the co-culture is to isolate and purify compounds separated by HPLC, which is inefficient and time-consuming. Furthermore, the overall changes in the metabolite profile cannot be well characterized. RESULTS: A new approach which integrates computational programs, MS-DIAL, MS-FINDER and web-based tools including GNPS and MetaboAnalyst, was developed to analyze and identify the metabolites of the co-culture of Aspergillus sydowii and Bacillus subtilis. A total of 25 newly biosynthesized metabolites were detected only in co-culture. The structures of the newly synthesized metabolites were elucidated, four of which were identified as novel compounds by the new approach. The accuracy of the new approach was confirmed by purification and NMR data analysis of 7 newly biosynthesized metabolites. The bioassay of newly synthesized metabolites showed that four of the compounds exhibited different degrees of PTP1b inhibitory activity, and compound N2 had the strongest inhibition activity with an IC50 value of 7.967 µM. CONCLUSIONS: Co-culture led to global changes of the metabolite profile and is an effective way to induce the biosynthesis of novel natural products. The new approach in this study is one of the effective and relatively accurate methods to characterize the changes of metabolite profiles and to identify novel compounds in co-culture systems.

Mycotoxins as inhibitors of protein tyrosine phosphatases from the deep-sea-derived fungus Aspergillus puniceus SCSIO z021.

Nine new xanthone-type and anthraquinone-type mycotoxins including austocystins J-N (1-5), 7-chloro versicolorin A (6), 3'-hydroxy-8-O-methyl versicolorin B (7), 8-O-methyl versiconol (8) and 2',3'-dihydroxy versiconol (9), together with 17 known analogues (10-26) were isolated from an extract of the deep-sea-derived fungus Aspergillus puniceus SCSIO z021. Their structures were elucidated by detailed analysis of spectroscopic data, and their absolute configurations were further determined by quantum chemical calculations of ECD spectra or comparison of the experimental ECD spectra. Eleven hydrogenated austocystins were synthesized from 1-2, 10-15 and 17 by catalytic hydrogenation for bioactivities evaluation. Totally, 18 of the all 37 compounds showed strong toxicity against brine shrimps or Vero cell, and the toxicity of 8-O-methyldemethylsterigmatocystin (18) (LC50 = 0.020 µM) against brine shrimps was higher than those of three positive controls. In addition, 22 of the isolated compounds also exhibited significant inhibitory activity against seven different protein tyrosine phosphatases (PTPs), among them austocystin H (15) and methyl-averantin (24) were the most potent inhibitors with IC50 values of 0.20-3.0 µM. Their structure-bioactivity relationship was also discussed.

Naphthacemycins from a Streptomyces sp. as Protein-Tyrosine Phosphatase Inhibitors.

Nine new naphthacemycins (1-9), along with one known naphthacemycin (10) were isolated from the culture of Streptomyces sp. N12W1565. Their structures were elucidated on the basis of spectroscopic analysis, including UV, NMR, and HRESIMS. All the compounds showed significant activity, with IC50 values less than 10 µM against protein-tyrosine phosphatase 1B (PTP1B). The anti-PTP1B structure-activity relationship of naphthacemycins (1-10) is discussed. These findings provide a promising starting point for the development of naphthacemycins as potential anti-PTP1B agents.

Discovery of naphthacemycins as a novel class of PARP1 inhibitors.

Poly (ADP-ribose) polymerase-1 (PARP-1) is an abundant nuclear protein that plays important roles in a variety of nuclear processes, and it has been proved a prominent target in oncology for its key function in DNA damage repair. In this study, we discovered a series of naphthacemycins as a new class of PARP1 inhibitors from a microbial metabolites library via high-throughput screening. Compound I, one of this series of compounds, could reduce cellular poly (ADP-ribose) level, trap PARP1 on the damaged DNA and elevate the level of γ-H2AX, and showed the selective cytotoxicity against BRCA1-deficient cell line. Our study provided a potential scaffold for the development of new PARP1 inhibitors in cancer therapy.

Diketopiperazine-Type Alkaloids from a Deep-Sea-Derived Aspergillus puniceus Fungus and Their Effects on Liver X Receptor α.

Eight new diketopiperazine-type alkaloids including four oxepin-containing diketopiperazine-type alkaloids, oxepinamides H-K (1-4), and four 4-quinazolinone alkaloids, puniceloids A-D (5-8), together with two known analogues (9 and 10), were isolated from the culture broth extracts of the deep-sea-derived fungus Aspergillus puniceus SCSIO z021. Their structures were elucidated by spectroscopic analyses, and their absolute configurations were determined by Marfey's method along with comparison of their specific rotations and ECD spectra. The absolute configurations of 4 and 5 were further confirmed by a single-crystal X-ray diffraction analysis. Compounds 1-8 showed significant transcriptional activation of liver X receptor α with EC50 values of 1.7-50 µM, and 7 and 8 were the most potent agonists.

Indole-Diterpenoids with Protein Tyrosine Phosphatase Inhibitory Activities from the Marine-Derived Fungus Penicillium sp. KFD28.

Five new indole-terpenoids named penerpenes E-I (1-5), along with seven known ones (6-12), were isolated from the marine-derived fungus Penicillium sp. KFD28 from a bivalve mollusk, Meretrix lusoria. The structures of the new compounds were elucidated from spectroscopic data and ECD spectroscopic analyses. Compound 1 was assigned as an indole-diterpenoid with a unique 6/5/5/6/6/5/5 heptacyclic ring system. Compound 2 represents an indole-diterpenoid with a new carbon skeleton derived from paxilline by the loss of three carbons (C-23/24/25). Compound 3 contains an additional oxygen atom between C-21 and C-22 compared to paxilline to form an unusual 6/5/5/6/6/7 hexacyclic ring system bearing a 1,3-dioxepane ring, which is rarely encountered in natural products. Compounds 1, 2, 4, and 6 showed inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) with IC50 values of 14, 27, 23, and 13 µM, respectively.

Identification and Characterization of HAESA-Like Genes Involved in the Fruitlet Abscission in Litchi.

Regulation of abscission is an important agricultural concern since precocious abscission can reduce crop yield. INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) peptide and its receptors the HAESA (HAE) and HAESA-like2 (HSL2) kinases have been revealed to be core components controlling floral organ abscission in the model plant Arabidopsis. However, it is still unclear whether the homologs of IDA-HAE/HSL2 in non-model plants are correlated to abscission. Previously, we found LcIDL1, a homolog of IDA from litchi, has a similar role to AtIDA in control of floral organ abscission in Arabidopsis. Here, we further isolated an HAESA-like homolog, LcHSL2, which is likely involved in the fruitlet abscission in litchi. Ectopic expression of LcHSL2 in wild type Arabidopsis has no effect on the floral organ abscission. However, its presence in the hae hsl2 mutant background completely rescued the floral organ abscission deficiency. LcHSL2 is localized in the cell membrane and the LcHSL2 gene is expressed at the pedicel abscission zone (AZ) of litchi and floral AZ of Arabidopsis. Real-time PCR analysis showed that the expression level of LcHSL2 was increased during ethephon-induced fruitlet abscission in litchi. Taken together, our findings suggest that HSL2 homologs have functional conservation in Arabidopsis and litchi, and LcHSL2 might play a critical role in regulation of fruitlet abscission in litchi.

Synthesis and biological evaluation of novel synthetic chalcone derivatives as anti-tumor agents targeting Cat L and Cat K.

A series of chalcone derivatives bearing benzamide or benzenesulfonamide moieties were synthesized and evaluated for their anti-tumor effect on HCT116, MCF7 and 143B cell lines in vitro. SAR analysis showed that compounds bearing a benzenesulfonamide group had greater potency than those bearing a benzamide group. It was also shown that compounds with a mono-methyl or mono-halogen group at the 3-position on the terminal phenyl ring were more effective than those with trifluoromethyl or methoxy groups. Compound 8e exhibited the most potent anti-tumor activities against HCT116, MCF7 and 143B cell lines, with IC50 values of 0.597, 0.886 and 0.791µM, respectively. Molecular docking studies and enzymatic assays demonstrated that the anti-tumor activity of compound 8e might be regulated by Cat L and Cat K.

Altenusin, a Nonsteroidal Microbial Metabolite, Attenuates Nonalcoholic Fatty Liver Disease by Activating the Farnesoid X Receptor.

Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disease. The incidence of NAFLD has increased steadily due to its close association with the global epidemic of obesity and type 2 diabetes. However, there is no effective pharmacological therapy approved for NAFLD. Farnesoid X receptor (FXR), a member of the nuclear receptor subfamily, plays important roles in maintaining the homeostasis of bile acids, glucose, and lipids. FXR agonists have shown promise for the treatment of NAFLD. In this study, we report altenusin (2076A), a natural nonsteroidal fungal metabolite, as a novel selective agonist of FXR with an EC50 value of 3.2 ± 0.2 µM. Administration of 2076A protected mice from high-fat diet (HFD)-induced obesity by reducing the body weight and fat mass by 22.9% and 50.0%, respectively. Administration of 2076A also decreased the blood glucose level from 178.3 ± 12.4 mg/dl to 116.2 ± 4.1 mg/dl and the serum insulin level from 1.4 ± 0.6 ng/dl to 0.4 ± 0.1 ng/dl. Moreover, 2076A treatment nearly reversed HFD-induced hepatic lipid droplet accumulation and macrovesicular steatosis. These metabolic effects were abolished in FXR knockout mice. Mechanistically, the metabolic benefits of 2076A might have been accounted for by the increased insulin sensitivity and suppression of genes that are involved in hepatic gluconeogenesis and lipogenesis. In summary, we have uncovered a new class of nonsteroidal FXR agonist that shows promise in treating NAFLD and the associated metabolic syndrome.

Varic acid analogues from fungus as PTP1B inhibitors: Biological evaluation and structure-activity relationships.

Protein tyrosine phosphatase 1B (PTP1B) inhibitors as potential therapies for diabetes and obesity have attracted much attention in recent years. Six varic acid analogues were isolated from two strains of fungi and evaluated for PTP1B inhibition activities. The structure-activity relationships were also characterized and predicted by molecular modeling. Further kinetic studies indicated the reversible and competitive inhibition manner of varic acid analogues. Trivaric acid showed insulin-sensitizing effect not only in vitro but also in vivo, representing a promising lead compound for further optimization.

Wortmannilactones I-L, new NADH-fumarate reductase inhibitors, induced by adding suberoylanilide hydroxamic acid to the culture medium of Talaromyces wortmannii.

With the aim of finding more potential inhibitors against NADH-fumarate reductase (specific target for treating helminthiasis and cancer) from natural resources, Talaromyces wortmannii was treated with the epigenome regulatory agent suberoylanilide hydroxamic acid, which resulted in the isolation of four new wortmannilactones derivatives (wortmannilactones I-L, 1-4). The structures of these new compounds were elucidated based on IR, HRESIMS and NMR spectroscopic data analyses. These four new compounds showed potent inhibitory activity against NADH-fumarate reductase with the IC50 values ranging from 0.84 to 1.35µM.