Further structural optimization and SAR study of sungsanpin derivatives as cell-invasion inhibitors.

Metastasis is one of the major causes of death in patients with cancer, and cell invasion plays a fundamental part in this process. Because of the absence of efficacious treatments, caring for these patients is challenging. Recently, we optimized the structure of the naturally occurring lasso peptide sungsanpin. We identified two peptides, octapeptide S3 and cyclic peptide S4, which inhibited invasion into A549 cells effectively. We undertook an alanine scan of S3 to explore the structure-activity relationship. The linear octapeptide S3-4 and cyclic peptide S4-1 exhibited improved inhibition of invasion into A549 cells. We modified S3-4 to obtain S3-4K, which displayed much higher inhibitory activity against invasion into A549 cells than S3-4. Of all peptides tested, S4-1 upregulated significantly mRNA of tissue inhibitor matrix metalloproteinase TIMP-1 and TIMP-2.

Design, synthesis, evaluation and optimization of novel azole analogues as potent antifungal agents.

In order to develop antifungal drugs, a series of novel azole analogues were designed and synthesized based on our previous work. Most of the target compounds had broad-spectrum antifungal activity, which showed excellent to moderate inhibitory activity against the tested strains, except A. fum 0504656. Among these, compounds B3, B7, B8, B11, B12 and E9 showed excellent activity against C. alb Y0109 and C. alb SC5314 (with the MIC80: 0.0156 ug/mL). In addition, compound B3 showed the best inhibitory activity against fluconazole-resistant strains C. alb 901 and C. alb 904, and had low toxicity against NIH/3T3 cells at the effective MIC range against fungi. Structure-activity relationship and docking studies of the derivatives suggest that the presence of the 2-fluoro-4-hydroxyphenyl and 1,2,3-triazole group enhance the antifungal activity of the compounds, which may be related to the interaction of the key groups with the amino acids surrounding the target enzyme.

SOS1-inspired hydrocarbon-stapled peptide as a pan-Ras inhibitor.

Blocking the interaction between Ras and Son of Sevenless homolog 1 (SOS1) has been an attractive therapeutic strategy for treating cancers involving oncogenic Ras mutations. K-Ras mutation is the most common in Ras-driven cancers, accounting for 86%, with N-Ras mutation and H-Ras mutation accounting for 11% and 3%, respectively. Here, we report the design and synthesis of a series of hydrocarbon-stapled peptides to mimic the alpha-helix of SOS1 as pan-Ras inhibitors. Among these stapled peptides, SSOSH-5 was identified to maintain a well-constrained alpha-helical structure and bind to H-Ras with high affinity. SSOSH-5 was furthermore validated to bind with Ras similarly to the parent linear peptide through structural modeling analysis. This optimized stapled peptide was proven to be capable of effectively inhibiting the proliferation of pan-Ras-mutated cancer cells and inducing apoptosis in a dose-dependent manner by modulating downstream kinase signaling. Of note, SSOSH-5 exhibited a high capability of crossing cell membranes and strong proteolytic resistance. We demonstrated that the peptide stapling strategy is a feasible approach for developing peptide-based pan-Ras inhibitors. Furthermore, we expect that SSOSH-5 can be further characterized and optimized for the treatment of Ras-driven cancers.

Trajectories of positive youth development and promotive factors among adolescents during the transition to high school in China.

Within the framework of positive youth development (PYD) and life course theory, this study was designed to examine patterns of PYD and promotive factors over the first semester of Chinese high school with a sample of 480 students (boys, 43.96%). The growth mixture model identified four trajectories of PYD, labeled high start-fast decreasing, high start-low decreasing, low start-low increasing, and mid-persistent. Results also showed that membership in a PYD trajectory is significantly related to three promotive factors: parental involvement, teacher involvement, and intentional self-regulation. These findings have important theoretical and practical insights for a deeper understanding of the underlying mechanisms of positive development in adolescents following the critical period surrounding the transition to high school.

Rational Optimizations of the Marine-Derived Peptide Sungsanpin as Novel Inhibitors of Cell Invasion.

Cancer metastasis, including cell invasion, is a major cause of poor clinical outcomes and death in numerous cancer patients. In recent years, many efforts have been made to develop potent therapeutic molecules from naturally derived peptides. Sungsanpin is a naturally derived lasso peptide that inhibits A549 cell invasion. We aimed to evaluate the potential of sungsanpin derivatives as candidates for anti-invasion drugs. We synthesized an analog of sungsanpin (Sun A) using a solid-phase peptide synthesis strategy (SPPS) and further modified its structure to improve its anti-invasion activity. All peptides were tested for their proliferative inhibition and anti-invasion activities in the A549 cell lines. Octapeptide S3 and cyclooctapeptide S4 upregulated the expression of TIMP-1 and TIMP-2 mRNA effectively and thus improved the inhibitory effect on the invasion of A549 cells. The two peptides can inhibit the invasion of A549 cells by up to 60 %, suggesting that they have potential as lead molecules for the development of peptide inhibitors.

How social connectedness contributes to life satisfaction among Chinese nurses: Testing potential moderated mediation pathways.

AIMS: The purpose of this study was to identify the mediating and moderating mechanisms by which social connectedness predicts life satisfaction among Chinese nurses. BACKGROUND: Previous researchers have primarily focused on sociodemographic and occupational domain risk factors for nurses' life satisfaction with relatively little insight into facilitative and protective factors and underlying psychological mechanisms. METHODS: We investigated 459 Chinese nurses' social connectedness, work-family enrichment, self-concept clarity, and life satisfaction via a cross-sectional design. We explored the underlying predictive mechanisms among these variables by creating a moderated mediation model. We followed STROBE checklist. RESULTS: Work-family enrichment played a mediating role in understanding the positive effects of social connectedness on nurses' life satisfaction. In addition, the moderating effect of self-concept clarity was manifested itself in the association between work-family enrichment and life satisfaction. DISCUSSION AND CONCLUSION: Interpersonal asset (social connectedness) and the positive aspect of the work-family interface (work-family enrichment) were significant contributors to nurses' life satisfaction. In particular, high self-concept clarity can enhance the beneficial effect of work-family enrichment on life satisfaction. IMPLICATIONS FOR NURSING POLICY AND PRACTICE: Strengthening social connectedness, promoting synergy in work-family roles, and maintaining a clarity of self-concept are important intervention pathways to enhance the health and well-being of nurses.

Synthesis and preliminary immunologic properties of di-/trisaccharide-conjugates related to Bacillus anthracis.

Herein, the di- and trisaccharide mimics of the hexasaccharide antigen related to Bacillus anthracis were synthesized and covalently coupled with carrier proteins, such as keyhole limpet hemocyanin (KLH) and bovine serum albumin (BSA), to form the corresponding glycoconjugates 1-6. 2,3,4,6-Tetra-O-benzyl thioglycoside and 2-deoxyl-2-phthalylamino-3,4,6-tri-O-benzyl thioglycoside were applied as glycosyl donors to guarantee α or ß-configuration of the newly formed glycosidic bonds. Glutaraldehyde was used as a homobifunctional cross-linker for high-efficiency coupling. The synthetic KLH-glycoconjugates 2, 4 and 6 were also used to vaccinate female Balb/c mice and the preliminary results of ELISA uncovered that all three KLH-conjugates could induce immune responses and generate oligosaccharide-specific total IgG antibodies. The trisaccharide 8, the glycosyl part of glycoconjugate 4, is of great immunogenicity.

Design, synthesis, and in vitro evaluation of novel antifungal triazoles containing substituted 1,2,3-triazole-methoxyl side chains.

In order to develop new triazole derivatives, we optimized the lead compound a6 by structural modifications to obtain a series of (2R,3R)-3-((1-substituted-1H-1,2,3-triazol-4-yl) methoxy)-2-(2,4-difluorophenyl)-1-(1H-1,2,4-triazol-1-yl) butan-2-ol, compounds 5-36. Most of the target compounds exhibited excellent in vitro antifungal activity against Candida albicans 10231 and Candida glabrata 537 with MIC ≤ 0.125 µg/mL. Of particular note, compounds 6, 22, 28, 30 and 36 were highly active against Candida neoformans 32609 with MIC ≤ 0.125 µg/mL and showed broad-spectrum antifungal activity including against fluconazole-resistant Candida auris 891. In addition, compounds 6 and 22 demonstrated inhibitory effects on filamentation in the azole-resistant C. albicans isolate. Moreover, compounds 6 and 22 were minimally toxic to HUVECs and possessed weak inhibitory effects on the human CYP3A4 and CYP2D6. SARs and docking study further indicated that ortho-substituted groups in the terminal phenyl ring can promote the compounds to improve their antifungal activity.

Synthesis, biological evaluation and molecular docking studies of novel diosgenin derivatives as anti-inflammatory agents.

Thirty-two novel DG F-spiroacetal ring-opening derivatives, including 24 acetylated derivatives and 8 nitrogenous derivatives, were designed and synthesized from diosgenin (DG). The cytotoxicity of the novel derivatives was evaluated by MTT assay, except for compounds 4a, 4e, 4i, 4 l, 5a and 5 h, which were potentially cytotoxic to RAW264.7 cells, all the other derivatives had no significant cytotoxicity. The NO release inhibitory activities of novel derivatives were screened by Griess method. The results showed that the anti-inflammatory activity of the DG acetylated derivatives was stronger than the nitrogenous derivatives, and 4a-4 m containing acetyl groups at the 3-position may have better anti-inflammatory effects than 5a-5 k containing free hydroxyl groups. In ELISA assay, compound 4 m exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by LPS with IC50 values 0.449 ± 0.050 µM. The results of docking experiments showed that 4 m has a good affinity for p65 protein.

Design, synthesis, and biological evaluation of stapled ascaphin-8 peptides.

Ascaphin-8 is an α-helical anti-tumor and antimicrobial peptide containing 19 residues, which was isolated from norepinephrine-stimulated skin secretions of the North American tailed frog Ascaphus truei. To improve both its stability and biological activities, a series of hydrocarbon-stapled analogs of Ascaphin-8 were synthesized and investigated for their potential antiproliferative activities. The activity studies were evaluated using the CCK-8 method and colony formation assay on human cancer cell lines. Ascaphin-8-3, as the most active peptide, showed a stronger inhibition effect when compared with the parent peptide for the tested cell lines. In addition, the effect of Ascaphin-8-3 on inhibiting the metastatic capabilities of A549 cells was more powerful than that of the parent peptide. This peptide derivative showed potentiality for further optimization in antitumor drugs.

Impact of moderate-to-severe psoriasis on quality of life in China: a qualitative study.

PURPOSE: Psoriasis is a serious health problem. Since limited research has investigated the impact of psoriasis on the quality of life of patients with moderate-to-severe psoriasis, this study aimed to explore this issue. METHODS: A qualitative study was conducted with 22 psoriasis patients from two cities in Shandong province of eastern China participating in one-to-one semi-structured in-depth interviews. RESULTS: Thematic analysis generated five major themes: (1) Symptoms, symptoms management and pain; (2) Functioning and activities of daily living (ADLs); (3) Psychological impact; (4) Social impact; (5) Employment and finances. CONCLUSION: Our study detailed the effects of psoriasis on patients' symptoms, symptoms management and pain, functioning and activities of daily living (ADLs), psychological impact, social impact, employment and finances. These data can provide a reference for studying the quality of life in patients with psoriasis.

Barriers to medication adherence for rural patients with mental disorders in eastern China: a qualitative study.

BACKGROUND: Mental disorders are destructive and usually require long-term medication, but non-adherence of medication is highly prevalent in patients with mental disorders. Previous studies relating to medication non-adherence were mainly quantitative. Meanwhile, there have been even fewer studies conducted in rural areas in China that focused on patients' medication non-adherence. This study aims to explore the barriers to medication adherence for rural patients with mental disorders in China from the perspectives of patients, patients' family members and healthcare providers. METHODS: A qualitative study was carried out in the rural areas of four towns within Shandong Province in eastern China. The study adheres to COREQ guidelines. Semi-structured in-depth interviews were conducted with 11 patients, 21 family members and 8 primary mental health service providers. RESULTS: Thematic analysis generated five major themes: (1) lack of self-insight, (2) inadequate family support, (3) long treatment duration and side effects of drugs, (4) poor economic conditions, and (5) the perceived stigma of illness. CONCLUSION: These findings may be useful for policymakers and planners to improve medication adherence and decrease the recurrence rate of mental disorders in China.

The life course health development model: a new approach to understanding human health.

The life course health development (LCHD) model is a cutting-edge theoretical model for the health science, which moves beyond the previous biomedical and biopsychosocial model. From the perspectives of "process, relationship and system", it recognizes health as a dynamic ability to change over the course of life, and highlights the importance of optimizing individual health trajectories and health promotion. According to LCHD model, we should understand health from the perspective of development, which is characterized by unfolding, complexity, timing, plasticity, thriving and harmony. Health research and practice, therefore, should change ideas from the focus on accurate diagnosis, treatment and etiology previously to full using the relative plasticity of human development to enhance health development ability, enrich health resources and promote the healthy development of physiology, psychology, behavior and culture system; and to achieve a harmonious balance in the different stages of the life course. Based on the LCHD model, it is suggested for our country's health service system (1) to strengthen the health education across the life-span and construct the health promotion model based on the social system; (2) to pay more attention to health promotion and disease prevention in early life; (3) to increase government spending on health promotion and prevention, not just on disease treatment.

Design, synthesis, and structure-activity relationship studies of novel triazole agents with strong antifungal activity against Aspergillus fumigatus.

The incidence of invasive fungal infections has dramatically increased for several decades. In order to discover novel antifungal agents with broad spectrum and anti-Aspergillus efficacy, a series of novel triazole derivatives containing 1,2,3-benzotriazin-4-one was designed and synthesized. Most of the compounds exhibited stronger in vitro antifungal activities against tested fungi than fluconazole. Moreover, 6m showed comparable antifungal activity against seven pathogenic strains as voriconazole and albaconazole, especially against Aspergillus fumigatus (MIC = 0.25 µg/ml), and displayed moderate antifungal activity against fluconazole-resistant strains of Candida albicans. A clear SAR study indicated that compounds with groups at the 7-position resulted in novel antifungal triazoles with more effectiveness and a broader-spectrum.

Design, synthesis, and in vitro evaluation of novel triazole analogues featuring isoxazole moieties as antifungal agents.

In order to develop novel antifungal agents, based on our previous work, a series of (2R,3R)-3-((3-substitutied-isoxazol-5-yl)methoxy)-2-(2,4-difluorophenyl)-1-(1H-1,2,4-triazol-1-yl) butan-2-ol (a1-a26) were designed and synthesized. All of the compounds exhibited good in vitro antifungal activities against eight human pathogenic fungi. Among them, compound a6 showed excellent inhibitory activity against Candida albicans and Candida parasilosis with MIC80 values of 0.0313 µg/mL. In addition, compounds a6, a9, a12, a13 and a14 exhibited moderate inhibitory activities against fluconazole-resistant isolates with MIC80 values ranging from 8 µg/mL to 16 µg/mL. Furthermore, compounds a6, a12 and a23 exhibited low inhibition profiles for CYP3A4. Clear SARs were analyzed, and the molecular docking experiment was carried out to further investigate the relationship between a6 and the target enzyme CYP51.

Subjective well-being among left-behind children in rural China: The role of ecological assets and individual strength.

BACKGROUND: The plight of left-behind children affected by parental migration has aroused widespread public concern in China. However, limited research has been conducted on the positive aspects of the development (e.g., subjective well-being) among left-behind children. Recently, a new means to investigating the mechanisms of positive development in left-behind children emerged from the positive youth development (PYD) approach. Grounded in the framework of PYD, this study was designed to examine how ecological assets (i.e., neighbourhood social cohesion and trusting relationships with caregivers) and individual strength (i.e., resilience) predict subjective well-being among left-behind children. METHODS: Altogether, 1,449 left-behind children (50.70% boys; Mage  = 12.11 years, SD = 1.84) were recruited to complete questionnaires designed to assess perceived neighbourhood social cohesion, trusting relationships with caregivers, resilience, and subjective well-being. RESULTS: The results show that neighbourhood social cohesion and trusting relationships with caregivers positively predicted left-behind children's subjective well-being. Moreover, structural equation modelling results reveal that resilience partially mediated the effect of neighbourhood social cohesion and trusting relationships with caregivers on subjective well-being. CONCLUSIONS: In this research, we identified key contextual and personal enablers for subjective well-being among left-behind children. The results provide some important implications regarding the manner in which subjective well-being can be promoted among left-behind children by increasing neighbourhood and family ecological assets and enhancing resilience.

Bridge-Caging Strategy in Phosphorus-Substituted Rhodamine for Modular Development of Near-Infrared Fluorescent Probes.

Replacement of the bridging oxygen atom in rhodamine with phosphorus is one of the most efficient ways for bright near-infrared (NIR) fluorophores with wavelengths over 700 nm. However, the organophosphorus bridge is more versatile than just being a spectrum tuner, it is also a profound solubility booster and photostability enhancer, as proved by a series of phosphorus-substituted rhodamines (PRBs). A unique bridge-caging strategy for efficiently manipulating fluorescence has further been innovated in example PRB2. Consistent with theoretical calculations, the formation of organophosphinate by a caging group as a fluorescence-controller locks the spirolactone into a colorless and nonfluorescent form, whereas decaging, a process induced by a specific stimulus, results in a ring-opened form, which yields strong fluorescence. The bridge-caging strategy is feasible for the modular development of NIR probes. Efficient in vivo imaging of photoillumination, hydrogen peroxide, and enzyme have been achieved on the PRB2 scaffold as a photoactivatable fluorophore, PRB2-hν; fluorescent indicator, PRB2-H2 O2 ; and fluorogenic enzyme substrate, PRB2-NTR, respectively.

Design, synthesis, and SAR study of 3-(benzo[d][1,3]dioxol-5-yl)-N-benzylpropanamide as novel potent synergists against fluconazole-resistant Candida albicans.

Based on our previous discovery and SAR study on the lead compounds 7d, 5 and berberine which can significantly enhance the susceptibility of fluconazole against fluconazole-resistant Candida albicans, a series of 3-(benzo[d][1,3]dioxol-5-yl)-N-(substituted benzyl)propanamides were designed, synthesized, and evaluated for their in vitro synergistic activity in combination with fluconazole. The series 2a-f were designed by replacing the amide moiety of the lead compound 7d with retro-amide moiety, and compounds 2a and 2b showed more activity than the lead 7d. Furthermore, introducing biphenyl moiety into series 2d-f afforded series 3a-r, most of which exhibited significantly superior activity to the series 2d-f. Especially, compound 3e, at a concentration of 1.0µg/ml, can enhance the susceptibility of fluconazole against fluconazole-resistant Candida albicans from 128.0µg/ml to 0.125-0.25µg/ml. A clear SAR of the compounds is discussed.

An Acid-Inert Fluorescent Probe for the Detection of Nitrite.

The fluorescent detection of nitrite ions has been challenging owing to the poor acid-stability of typical fluorescent probes. Herein, an acid-inert rhodamine-based fluorescent probe has been developed for the fast detection of trace amount of nitrite ions with turn-on mode. The detection limit of nitrite ions was determined to be 9.4 nM (S/N = 3) and the linear range with high linear correlation was observed between 0.025 to 2.5 µM. A test paper method was developed for rapid visual detection of nitrite ions. Quantitative analysis of two real water samples also confirmed the reliability and sensitivity of the developed fluorescent method.

Synthesis and Antibacterial Evaluation of a Series of 11,12-Cyclic Carbonate Azithromycin-3-O-descladinosyl-3-O-carbamoyl Glycosyl Derivatives.

A novel series of 11,12-cyclic carbonate azithromycin-3-O-descladinosyl-3-O-carbamoyl glycosyl derivatives were designed, synthesized, and evaluated for their antibacterial activities in vitro. Most of these compounds had significant antibacterial activity against seven kinds of susceptible strains. In particular, compound G1 exhibited the most potent activity against methicillin-resistant Streptococcus pneumoniae 943 (MIC: 1 µg/mL), Staphylococcus pneumoniae 746 (MIC: 2 µg/mL), Streptococcus pyogenes 447 (MIC: 8 µg/mL), and Escherichia coli 236 (MIC: 32 µg/mL), which were two-, four-, four-, four-, and eight-fold stronger activity than azithromycin, respectively. Additionally, compound G2 exhibited improved activity against methicillin-resistant Staphylococcus aureus MRSA-1 (MIC: 8 µg/mL), Streptococcus pneumoniae 943 (MIC: 2 µg/mL), Staphylococcus pneumoniae 746 (MIC: 2 µg/mL), and Escherichia coli 236 (MIC: 32 µg/mL), which were two-, two-, four-, and eight-fold better activity than azithromycin, respectively. As for methicillin-resistant Staphylococcus aureus MRSA-1, compound G6 presented the most excellent activity (MIC: 4 µg/mL), showing four-fold higher activity than azithromycin (MIC: 16 µg/mL) and erythromycin (MIC: 16 µg/mL). However, compared with other compounds, compounds G7 and G8 with the disaccharide side chain were observed the lower activity against seven strains.