scholarly journals The Effect of Cytochalasans on the Actin Cytoskeleton of Eukaryotic Cells and Preliminary Structure–Activity Relationships

Biomolecules ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 73 ◽  
Author(s):  
Robin Kretz ◽  
Lucile Wendt ◽  
Sarunyou Wongkanoun ◽  
J. Luangsa-ard ◽  
Frank Surup ◽  
...  
Keyword(s):  
Actin Cytoskeleton ◽  
High Resolution Mass Spectrometry ◽  
Structural Features ◽  
Eukaryotic Cells ◽  
Hydroxyl Group ◽  
Fungal Metabolites ◽  
Factors Affecting ◽  
Structure Activity ◽  
Exact Effect

In our ongoing search for new bioactive fungal metabolites, two new cytochalasans were isolated from stromata of the hypoxylaceous ascomycete Hypoxylon fragiforme. Their structures were elucidated via high-resolution mass spectrometry (HR-MS) and nuclear magnetic resonance (NMR) spectroscopy. Together with 23 additional cytochalasans isolated from ascomata and mycelial cultures of different Ascomycota, they were tested on their ability to disrupt the actin cytoskeleton of mammal cells in a preliminary structure–activity relationship study. Out of all structural features, the presence of hydroxyl group at the C7 and C18 residues, as well as their stereochemistry, were determined as important factors affecting the potential to disrupt the actin cytoskeleton. Moreover, reversibility of the actin disrupting effects was tested, revealing no direct correlations between potency and reversibility in the tested compound group. Since the diverse bioactivity of cytochalasans is interesting for various applications in eukaryotes, the exact effect on eukaryotic cells will need to be determined, e.g., by follow-up studies involving medicinal chemistry and by inclusion of additional natural cytochalasans. The results are also discussed in relation to previous studies in the literature, including a recent report on the anti-Biofilm activities of essentially the same panel of compounds against the pathogenic bacterium, Staphylococcus aureus.

scholarly journals Structure–Activity Relationship of Phytotoxic Natural 10-Membered Lactones and Their Semisynthetic Derivatives

2021 ◽  
Vol 7 (10) ◽  
pp. 829
Author(s):  
Anna Dalinova ◽  
Anatoly Fedorov ◽  
Vsevolod Dubovik ◽  
Olga Voitsekhovskaja ◽  
Elena Tyutereva ◽  
...  
Keyword(s):  
Rational Design ◽  
Fungicidal Activity ◽  
Structural Features ◽  
Hydroxyl Group ◽  
High Yield ◽  
Sf9 Cells ◽  
Structure Activity ◽  
Relationship Of ◽  
Derivatives Of ◽  
Target Activity

Ten-membered lactones (nonenolides) demonstrate phytotoxic, antimicrobial, and fungicidal activity promising for the development of natural product-derived pesticides. The fungus Stagonospora cirsii is able to produce phytotoxic stagonolides A (1), J (2), K (3) and herbarumin I (4) with high yield. The aim of this study was to create a set of structurally related nonenolides and to reveal the structural features that affect their biological activity. Stagonolide A (1) and C-7 oxidized stagonolide K (11) showed the highest phytotoxicity in leaf puncture assay and agar seedlings assay. The oxidation of C-7 hydroxyl group (as in 1, acetylstagonolide A (10) and (11) led to the manifestation of toxicity to microalgae, Bacillus subtilis and Sf9 cells regardless of the configuration of C-9 propyl chains (R in 1 and 10, S in 11). C-7 non-oxidized nonenolides displayed none or little non-target activity. Notably, 7S compounds were more phytotoxic than their 7R analogues. Due to the high inhibitory activity against seedling growth and the lack of side toxicity, mono- and bis(acetyl)- derivatives of herbarumin I were shown to be potent for the development of pre-emergent herbicides. The identified structural features can be used for the rational design of new herbicides.

HAZARD: An Expert System for Risk Assessment of Environmental Chemicals

1987 ◽  
Vol 26 (01) ◽  
pp. 13-23 ◽  
Author(s):  
H. W. Gottinger
Keyword(s):  
Expert System ◽  
Structural Information ◽  
Chemical Carcinogenesis ◽  
Structural Features ◽  
Environmental Chemicals ◽  
Chemical Carcinogens ◽  
Carcinogenic Activity ◽  
Current State ◽  
Structure Activity ◽  
Carcinogenic Potential

AbstractThe purpose of this paper is to report on an expert system in design that screens for potential hazards from environmental chemicals on the basis of structure-activity relationships in the study of chemical carcinogenesis, particularly with respect to analyzing the current state of known structural information about chemical carcinogens and predicting the possible carcinogenicity of untested chemicals. The structure-activity tree serves as an index of known chemical structure features associated with carcinogenic activity. The basic units of the tree are the principal recognized classes of chemical carcinogens that are subdivided into subclasses known as nodes according to specific structural features that may reflect differences in carcinogenic potential among chemicals in the class. An analysis of a computerized data base of known carcinogens (knowledge base) is proposed using the structure-activity tree in order to test the validity of the tree as a classification scheme (inference engine).

Factors Affecting the Use and Consequences of Management Accounting Practices in A Transitional Economy: The Case of Vietnam

2016 ◽  
pp. 54-73 ◽  
Author(s):  
Anh Doan Ngoc Phi
Keyword(s):  
Significant Influence ◽  
Quantitative Data ◽  
Structural Equation ◽  
Qualitative Data ◽  
Management Accounting ◽  
Transitional Economy ◽  
Equation Modeling ◽  
Enterprise Performance ◽  
Factors Affecting

This study seeks to help fill an important gap in the literature by investigating factors that have facilitated the use of management accounting practices (MAPs) in Vietnam - a transitional economy. Data were collected from 220 medium-to-large enterprises. Follow-up interviews were conducted with 20 accounting heads/vice heads to obtain further information and clarification. The quantitative data collected was analyzed using both descriptive and inferential statistics (including t-tests and structural equation modeling), while the qualitative data was used to shed further light on the various relationships described by the quantitative analysis. This paper reveals that both decentralization and competition have a positive, significant influence on the use of new MAPs except for the old ones. Consequently, the use of MAPs has a positive, significant influence on enterprise performance.

STRUCTURAL AND DYNAMIC FEATURES OF EAR-LY DISABILITY DUE TO MENTAL DISEASES

2020 ◽  
pp. 62-67
Author(s):  
Shmakova O.P.
Keyword(s):  
People With Disabilities ◽  
Child And Adolescent Psychiatry ◽  
Child Psychiatrist ◽  
Childhood And Adolescence ◽  
Disabled Children ◽  
Dynamic Features ◽  
Factors Affecting ◽  
Number Of Children ◽  
Number Of Patients

Prevention of disability is one of the most significant tasks of child and adolescent psychiatry. Obtaining data on the dynamics of the number of people with disabilities and the factors affecting this indicator seems to be one of the relevant aspects. Aim: to trace the dynamics of the number of children with disabili-ties and to assess the change in the structure of early disability over the past decades. Materials and Meth-ods. A comparative analysis of two cohorts of patients was carried out: 1st - patients born in 1990-1992. (1203 patients (men - 914, 76%; women - 289, 24%)) who applied to the district neuropsychiatric dispensa-ry for outpatient care in childhood and adolescence; II - children and adolescents born in 2005 - 2018 (602 patients (male - 410, 68%; female - 192, 32%), ob-served at the time of the study by a child psychiatrist in the neuropsychiatric dispensary. Research methods: clinical and psychopathological; follow-up; statisti-cal. Results. Comparison of the number and nosologi-cal distribution of disabled children in two cohorts showed that over the 15th year there has been a shift towards an increase in the proportion of disabled children among patients observed by child and ado-lescent psychiatrists. The increase in the number of children with disabilities was due to those suffering from childhood autism and other disorders of general development. There were no statistically significant differences in the number of people with disabilities who received benefits before the age of 7, as well as differences in gender ratios among disabled people in the two cohorts. Conclusion. Early disability is a mul-tifactorial phenomenon, prevalence, dynamics, the structure of which depends not only on clinical, but also on socio-administrative realities. Children with autism require increased attention, since there has been a multiple increase in the number of patients with this diagnosis.

scholarly journals Protein Analysis of Pollen Tubes after the Treatments of Membrane Trafficking Inhibitors Gains Insights on Molecular Mechanism Underlying Pollen Tube Polar Growth

2021 ◽  
Vol 40 (2) ◽  
pp. 205-222
Author(s):  
Monica Scali ◽  
Alessandra Moscatelli ◽  
Luca Bini ◽  
Elisabetta Onelli ◽  
Rita Vignani ◽  
...  
Keyword(s):  
Pollen Tube ◽  
Actin Cytoskeleton ◽  
Membrane Trafficking ◽  
Tip Growth ◽  
Male Gametophyte ◽  
Pollen Tubes ◽  
Structural Features ◽  
Two Dimensional Gel Electrophoresis ◽  
Depth Analysis

AbstractPollen tube elongation is characterized by a highly-polarized tip growth process dependent on an efficient vesicular transport system and largely mobilized by actin cytoskeleton. Pollen tubes are an ideal model system to study exocytosis, endocytosis, membrane recycling, and signaling network coordinating cellular processes, structural organization and vesicular trafficking activities required for tip growth. Proteomic analysis was applied to identifyNicotiana tabacumDifferentially Abundant Proteins (DAPs) after in vitro pollen tube treatment with membrane trafficking inhibitors Brefeldin A, Ikarugamycin and Wortmannin. Among roughly 360 proteins separated in two-dimensional gel electrophoresis, a total of 40 spots visibly changing between treated and control samples were identified by MALDI-TOF MS and LC–ESI–MS/MS analysis. The identified proteins were classified according to biological processes, and most proteins were related to pollen tube energy metabolism, including ammino acid synthesis and lipid metabolism, structural features of pollen tube growth as well modification and actin cytoskeleton organization, stress response, and protein degradation. In-depth analysis of proteins corresponding to energy-related pathways revealed the male gametophyte to be a reliable model of energy reservoir and dynamics.

scholarly journals The Inhibitory Effects of Plant Derivate Polyphenols on the Main Protease of SARS Coronavirus 2 and Their Structure–Activity Relationship

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1924
Author(s):  
Thi Thanh Hanh Nguyen ◽  
Jong-Hyun Jung ◽  
Min-Kyu Kim ◽  
Sangyong Lim ◽  
Jae-Myoung Choi ◽  
...  
Keyword(s):  
Structure Activity Relationship ◽  
Garlic Extract ◽  
Activity Relationship ◽  
Hydroxyl Group ◽  
Inhibitory Effects ◽  
Structure Activity ◽  
Main Protease ◽  
Ic50 Values ◽  
Km Value ◽  
Novel Coronavirus

The main protease (Mpro) is a major protease having an important role in viral replication of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the novel coronavirus that caused the pandemic of 2020. Here, active Mpro was obtained as a 34.5 kDa protein by overexpression in E. coli BL21 (DE3). The optimal pH and temperature of Mpro were 7.5 and 37 °C, respectively. Mpro displayed a Km value of 16 μM with Dabcyl-KTSAVLQ↓SGFRKME-Edans. Black garlic extract and 49 polyphenols were studied for their inhibitory effects on purified Mpro. The IC50 values were 137 μg/mL for black garlic extract and 9–197 μM for 15 polyphenols. The mixtures of tannic acid with puerarin, daidzein, and/or myricetin enhanced the inhibitory effects on Mpro. The structure–activity relationship of these polyphenols revealed that the hydroxyl group in C3′, C4′, C5′ in the B-ring, C3 in the C-ring, C7 in A-ring, the double bond between C2 and C3 in the C-ring, and glycosylation at C8 in the A-ring contributed to inhibitory effects of flavonoids on Mpro.

Coronary endarterectomy in coronary artery disease: Factors affecting graft patency and survival

2021 ◽  
pp. 021849232110068
Author(s):  
Simon CY Chow ◽  
Jacky YK Ho ◽  
Micky WT Kwok ◽  
Takuya Fujikawa ◽  
Kevin Lim ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Graft Patency ◽  
Complete Revascularization ◽  
Coronary Endarterectomy ◽  
Factors Affecting ◽  
Early Results ◽  
Cerebrovascular Events ◽  
Obtuse Marginal ◽  
One Year

Background Coronary endarterectomy aims to improve completeness of revascularization in patients with occluded coronary vessels. The benefits of coronary endarterectomy remain uncertain. The aim of this study was to evaluate short-term surgical outcomes and factors affecting graft patency post-coronary endarterectomy. Methods Between 2009 and 2019, 81 consecutive patients who had coronary endarterectomy done were evaluated for their perioperative and early results. A total of 36 patients with follow-up coronary studies were included in patency analysis. Mortality rates, major adverse cardiac and cerebrovascular events, and graft patency were outcomes of interest. Survival and risk factor analysis were performed with Kaplan–Meier and logistic regression analysis. Results The average age of the cohort was 61.9 ± 9.29 years. Complete revascularization rate was 95.4% post-coronary endarterectomy. The 30-day and 1-year mortality was 2.5 and 6.2%, respectively. One-year major adverse cardiac and cerebrovascular events rate was 11.1%. Periprocedural myocardial infarction rate was 7.4%. Three patients required repeat revascularization within a mean follow-up duration of 49.6 ± 36.5 months. Overall graft patency was 89.2% at 20.2 months and graft patency post-coronary endarterectomy was 85.4%. Arterial grafts showed 100% patency. Vein grafts to endarterectomized obtuse marginal branch had patency rates of 33.3%. Multiple endarterectomies were associated with worse one-year major adverse cardiac and cerebrovascular events (OR: 28.6 ± 1.16; P = 0.003). Conclusions Coronary endarterectomy facilitates completeness of revascularization and does not increase early mortality. Graft patency post-coronary endarterectomy on obtuse marginal artery was suboptimal. Judicious use of coronary endarterectomy should be practiced to balance the need of completeness of revascularization against the risk of myocardial infarction.

scholarly journals Factors Affecting the Control of Chronic Rhinosinusitis With Nasal Polyps: A Comparison in Patients With or Without NERD

2021 ◽  
Vol 12 ◽  
pp. 215265672110038
Author(s):  
Markus Jukka Lilja ◽  
Anni Koskinen ◽  
Paula Virkkula ◽  
Seija Inkeri Vento ◽  
Jyri Myller ◽  
...  
Keyword(s):  
Chronic Rhinosinusitis ◽  
Nasal Polyps ◽  
Female Gender ◽  
Sinus Surgery ◽  
Logrank Test ◽  
Free Survival ◽  
Factors Affecting ◽  
Advanced Therapy ◽  
And Gender

Objectives The aim was to compare the control of chronic rhinosinusitis with nasal polyps (CRSwNP) after endoscopic sinus surgery (ESS), in patients with/without nonsteroidal anti-inflammatory drug exacerbated respiratory disease (NERD). Study Desing: A retrospective hospital-based sample of CRSwNP patients with/without NERD with follow-up. Setting Tertiary rhinology centers. Methods Electronic patient record data from 116 CRSwNP patients (46 with NERD and 70 without NERD) undergoing ESS during 2001–17 were studied. Mean follow-up time was 9.9 years (range 1.1–15.3). Endpoints reflecting uncontrolled CRSwNP were revision ESS, and need for rescue/advanced therapy (e.g. antibiotics, oral corticosteroids and/or biological therapy) during follow-up. NERD was variable of interest and gender, age, asthma, allergic rhinitis (AR), smoking, Lund-Mackay (LM) score of sinus computed tomography scans previous ESS and baseline total ethmoidectomy were used as covariates. Results Twenty-one (49.7%) NERD patients and 18 (25.7%) non-NERD patients underwent revision ESS within a mean ± SD of 4.3 ± 2.8 and 3.7 ± 2.6 years, respectively (p = .013, by Logrank test). In Cox´s regression models, NERD, female gender, young age, asthma, AR, previous ESS, and lack of total ethmoidectomy were associated with revision-ESS. In adjusted model, only the total ethmoidectomy predicted revision-free survival. In adjusted logistic regression model, there was an insignificant trend that NERD and LM score were associated with the need for rescue/advanced therapy in the follow-up. Conclusions Patients with NERD had higher risk of uncontrolled CRSwNP than patient group without NERD, as measured by revision ESS and/or need for rescue/advanced therapy in the follow-up. In addition, baseline total ethmoidectomy was associated with revision-free survival.

scholarly journals Factors affecting cyberloafing in computer laboratory teaching settings

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Sacip Toker ◽  
Meltem Huri Baturay
Keyword(s):  
Negative Attitudes ◽  
Computer Laboratory ◽  
Factors Affecting ◽  
Computer Lab ◽  
Student Demographics ◽  
Internet Skills ◽  
Laboratory Teaching ◽  
Convenience Sampling ◽  
Teaching Setting

AbstractThis correlational study investigated the factors affecting cyberloafing behavior in an educational environment, specifically that of a computer laboratory teaching setting. A total of 272 students selected using convenience sampling responded to a questionnaire that collected data about cyberloafing behavior and student demographics, personality type, sense of belonging, motivation, locus of control and teacher evaluation (respect, activities, communication, motivation) as well as computer lab teaching settings and norms. The results indicated that students in computer lab teaching settings cyberloaf mainly for socialization, followed by personal business and news follow-up. Males cyberloaf more frequently than females, especially for personal business and news follow-up. As students’ internet skills increase, so does their cyberloafing, particularly for personal business and socialization. A lack of instructor norms in computer lab lectures and student amotivation are also associated with increases in cyberloafing for personal business, whereas instructors’ respect for students and negative attitudes towards cyberloafing are associated with decreases in cyberloafing for socialization. This paper discusses the study findings in detail and makes recommendations for additional research.

scholarly journals Cohort profile: the Chinese Pregnant Women Cohort Study and Offspring Follow-up (CPWCSaOF)

BMJ Open ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. e044933
Author(s):  
Tianchen Lyu ◽  
Yunli Chen ◽  
Yongle Zhan ◽  
Yingjie Shi ◽  
Hexin Yue ◽  
...  
Keyword(s):  
Cohort Study ◽  
Pregnant Women ◽  
First Trimester ◽  
Health Problems ◽  
Environmental Data ◽  
Geographical Information ◽  
Obstetric Outcomes ◽  
Factors Affecting ◽  
Link Type

PurposeA multicentre prospective cohort study, known as the Chinese Pregnant Women Cohort Study (CPWCS), was established in 2017 to collect exposure data during pregnancy (except environmental exposure) and analyse the relationship between lifestyle during pregnancy and obstetric outcomes. Data about mothers and their children’s life and health as well as children’s laboratory testing will be collected during the offspring follow-up of CPWCS, which will enable us to further investigate the longitudinal relationship between exposure in different periods (during pregnancy and childhood) and children’s development.Participants9193 pregnant women in 24 hospitals in China who were in their first trimester (5–13 weeks gestational age) from 25 July 2017 to 26 November 2018 were included in CPWCS by convenience sampling. Five hospitals in China which participated in CPWCS with good cooperation will be selected as the sample source for the Chinese Pregnant Women Cohort Study (Offspring Follow-up) (CPWCS-OF).Findings to dateSome factors affecting pregnancy outcomes and health problems during pregnancy have been discovered through data analysis. The details are discussed in the ‘Findings to date’ section.Future plansInfants and children and their mothers who meet the criteria will be enrolled in the study and will be followed up every 2 years. The longitudinal relationship between exposure (questionnaire data, physical examination and biospecimens, medical records, and objective environmental data collected through geographical information system and remote sensing technology) in different periods (during pregnancy and childhood) and children’s health (such as sleeping problem, oral health, bowel health and allergy-related health problems) will be analysed.Trail registration numberCPWCS was registered with ClinicalTrials.gov on 18 January 2018: NCT03403543. CPWCS-OF was registered with ClinicalTrials.gov on 24 June 2020: NCT04444791.

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