Flow with Variable Number of Phases: Method of Negative Saturations

Background:Obesity is a chronic condition associated with poorer cognitive functioning. Wisconsin Card Sorting Test (WCST) is a useful tool for evaluating executive functions. In this study, we assessed the association between dopaminergic gene polymorphisms: DAT1 (SLC6A3), COMTVal158Met, DRD4 (48-bp variable number of tandem repeats - VNTR) and WCST parameters to investigate the functions of the frontal lobes in obese individuals.Objective:To find the significant correlations between polymorphisms of DAT1, COMTVal158Met, DRD4 and executive functions in obese subjects.Methods:The analysis of the frequency of individual alleles was performed in 248 obese patients (179 women, 69 men). Evaluation of the prefrontal cortex function (operating memory and executive functions) was measured with the Wisconsin Card Sorting Test (WCST). Separate analyzes were performed in age subgroups to determine different activities and regulation of genes in younger and older participants.Results:Scores of WCST parameters were different in the subgroups of women and men and in the age subgroups. Regarding the COMT gene, patients with A/A and G/A polymorphisms showed significantly better WCST results in WCST_P, WCST_CC and WCST_1st. Regarding DAT1 men with L/L and L/S made less non-perseverative errors, which was statistically significant. In DRD4, significantly better WCST_1st results were found only in older women with S allele.Conclusion:Obtained results indicate the involvement of dopaminergic transmission in the regulation of prefrontal cortex function. Data analysis indicates that prefrontal cortex function may ensue, from different elements such as genetic factors, metabolic aspects of obesity, and hormonal activity (estrogen).

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Antifúngicos poliénicos. Mecanismo de acción y aplicaciones

Studies in the Economic History of Southern Africa ◽

10.22201/fm.24484865e.2020.63.2.02 ◽

2020 ◽

Vol 63 (2) ◽

pp. 7-17

Author(s):

Evelyn Rivera-Toledo ◽

Alan Uriel Jiménez-Delgadillo ◽

Patricia Manzano-Gayosso

Keyword(s):

Antifungal Activity ◽

Key Words ◽

Secondary Metabolism ◽

Amphotericin B ◽

Antifungal Agents ◽

Fungal Infections ◽

Variable Number ◽

Therapeutic Failure ◽

Morbidity And Mortality ◽

Clinical Use

The first compounds with specific antifungal activity were identified in the middle of the last century as a product of the secondary metabolism of bacteria of the order Actinomycetales, and their clinical use significantly diminished the morbidity and mortality associated with severe fungal infections. Many of such biosynthetic compounds are characterized by a chemical polygenic structure, with a variable number of carbon-carbon double bonds. Currently, besides polygenic antimycotics, there are other antifungal agents, such as the azole compounds, that have less toxicity in patients; however, cases of therapeutic failure with such compounds have been documented, therefore, the use of polygenics is still the best alternative in such cases. This review presents data about the properties and applications of antifungal-polygenic compounds using amphotericin B as a model. Key words: Amphotericin B; antifungal polyenes; ergosterol

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Characterisation of Plasticity Response for Reciprocating Sliding Wear Test of Ti-6Al-4V under Variables Number of Cycles

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.773-774.168 ◽

2015 ◽

Vol 773-774 ◽

pp. 168-172

Author(s):

D. Harun ◽

D. Nalatambi ◽

Ramdziah Md. Nasir ◽

Abdul Latif Mohd Tobi

Keyword(s):

Plastic Deformation ◽

Titanium Alloy ◽

Sliding Wear ◽

Wear Track ◽

Wear Test ◽

Optical Microscope ◽

Variable Number ◽

Reciprocating Sliding ◽

Number Of Cycles ◽

Reciprocating Sliding Wear

Reciprocating sliding wear test of uncoated titanium alloy, Ti-6Al-4V is investigated using pin-on-flat contact arrangement of Ti-6Al-4V/Ti-6Al-4V pair under variable number of cycles at low number of cycles. The worn surfaces of the titanium alloy specimens were analyzed with the use of optical microscope (2D and 3D OM) and Vickers Hardness analysis was carried on. The pattern of the wear scar characteristics determined and the finding at the end of wear track had been focus through the presence at the end of wear track. It is suggesting an evidence of plastic deformation with the increasing in hardness value. The increase in hardness value at the end of wear track indicates increase in the plastic deformation with increasing number of cycles.

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Modelling and Multi-Objective Optimization of the Sulphur Dioxide Oxidation Process

Processes ◽

10.3390/pr9061072 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1072

Author(s):

Mohammad Reza Zaker ◽

Clémence Fauteux-Lefebvre ◽

Jules Thibault

Keyword(s):

Sulphuric Acid ◽

Sulphur Dioxide ◽

Variable Number ◽

Inlet Temperature ◽

Multi Objective Optimization ◽

Absorption Column ◽

Maximum Reaction Rate ◽

Multi Objective ◽

Maximum Reaction

Sulphuric acid (H2SO4) is one of the most produced chemicals in the world. The critical step of the sulphuric acid production is the oxidation of sulphur dioxide (SO2) to sulphur trioxide (SO3) which takes place in a multi catalytic bed reactor. In this study, a representative kinetic rate equation was rigorously selected to develop a mathematical model to perform the multi-objective optimization (MOO) of the reactor. The objectives of the MOO were the SO2 conversion, SO3 productivity, and catalyst weight, whereas the decisions variables were the inlet temperature and the length of each catalytic bed. MOO studies were performed for various design scenarios involving a variable number of catalytic beds and different reactor configurations. The MOO process was mainly comprised of two steps: (1) the determination of Pareto domain via the determination a large number of non-dominated solutions, and (2) the ranking of the Pareto-optimal solutions based on preferences of a decision maker. Results show that a reactor comprised of four catalytic beds with an intermediate absorption column provides higher SO2 conversion, marginally superior to four catalytic beds without an intermediate SO3 absorption column. Both scenarios are close to the ideal optimum, where the reactor temperature would be adjusted to always be at the maximum reaction rate. Results clearly highlight the compromise existing between conversion, productivity and catalyst weight.

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Biotin-Containing Third Generation Glucoheptoamidated Polyamidoamine Dendrimer for 5-Aminolevulinic Acid Delivery System

International Journal of Molecular Sciences ◽

10.3390/ijms22041982 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1982 ◽

Cited By ~ 1

Author(s):

Aleksandra Kaczorowska ◽

Małgorzata Malinga-Drozd ◽

Wojciech Kałas ◽

Marta Kopaczyńska ◽

Stanisław Wołowiec ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Aminolevulinic Acid ◽

Reactive Oxygen ◽

Pamam Dendrimer ◽

Variable Number ◽

Amide Bond ◽

Oxygen Species ◽

Nmr Spectrum ◽

Guest Molecules ◽

Amine Groups

Polyamidoamine PAMAM dendrimer generation 3 (G3) was modified by attachment of biotin via amide bond and glucoheptoamidated by addition of α-D-glucoheptono-1,4-lacton to obtain a series of conjugates with a variable number of biotin residues. The composition of conjugates was determined by detailed 1-D and 2-D NMR spectroscopy to reveal the number of biotin residues, which were 1, 2, 4, 6, or 8, while the number of glucoheptoamide residues substituted most of the remaining primary amine groups of PAMAM G3. The conjugates were then used as host molecules to encapsulate the 5-aminolevulinic acid. The solubility of 5-aminolevulinic acid increased twice in the presence of the 5-mM guest in water. The interaction between host and guest was accompanied by deprotonation of the carboxylic group of 5-aminolevulinic acid and proton transfer into internal ternary nitrogen atoms of the guest as evidenced by a characteristic chemical shift of resonances in the 1H NMR spectrum of associates. The guest molecules were most likely encapsulated inside inner shell voids of the host. The number of guest molecules depended on the number of biotin residues of the host, which was 15 for non-biotin-containing glucoheptoamidated G3 down to 6 for glucoheptoamidated G3 with 8 biotin residues on the host surface. The encapsulates were not cytotoxic against Caco-2 cells up to 200-µM concentration in the dark. All encapsulates were able to deliver 5-aminolevulinic acid to cells but aqueous encapsulates were more active in this regard. Simultaneously, the reactive oxygen species were detected by staining with H2DCFDA in Caco-2 cells incubated with encapsulates. The amount of PpIX was sufficient for induction of reactive oxygen species upon 30-s illumination with a 655-nm laser beam.

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The Prevalence of Virulence Determinants and Antibiotic Resistance Patterns in Methicillin—Resistant Staphylococcus aureus in a Nursing Home in Poland

Pathogens ◽

10.3390/pathogens10040427 ◽

2021 ◽

Vol 10 (4) ◽

pp. 427

Author(s):

Martyna Kasela ◽

Agnieszka Grzegorczyk ◽

Bożena Nowakowicz-Dębek ◽

Anna Malm

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Variable Number Tandem Repeat ◽

Multidrug Resistant ◽

Variable Number ◽

Pulse Field ◽

Virulence Determinants ◽

Gene Encoding ◽

Methicillin Resistant ◽

Pulse Field Gel Electrophoresis

Nursing homes (NH) contribute to the regional spread of methicillin-resistant Staphylococcus aureus (MRSA). Moreover, residents are vulnerable to the colonization and subsequent infection of MRSA etiology. We aimed at investigating the molecular and phenotypic characteristics of 21 MRSA collected from the residents and personnel in an NH (Lublin, Poland) during 2018. All MRSA were screened for 20 genes encoding virulence determinants (sea-see, eta, etb, tst, lukS-F-PV, eno, cna, ebpS, fib, bbp, fnbA, fnbB, icaADBC) and for resistance to 18 antimicrobials. To establish the relatedness and clonal complexes of MRSA in NH we applied multiple-locus variable-number tandem-repeat fingerprinting (MLVF), pulse field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing. We identified four sequence types (ST) among two clonal complexes (CC): ST (CC22) known as EMRSA-15 as well as three novel STs—ST6295 (CC8), ST6293 (CC8) and ST6294. All tested MRSA were negative for sec, eta, etb, lukS-F-PV, bbp and ebpS genes. The most prevalent gene encoding toxin was sed (52.4%; n = 11/21), and adhesins were eno and fnbA (100%). Only 9.5% (n = 2/21) of MRSA were classified as multidrug-resistant. The emergence of novel MRSA with a unique virulence and the presence of epidemic clone EMRSA-15 creates challenges for controlling the spread of MRSA in NH.

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Molecular characteristics of Brucella melitensis isolates from humans in Qinghai Province, China

Infectious Diseases of Poverty ◽

10.1186/s40249-021-00829-0 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Zhi-Jun Zhao ◽

Ji-Quan Li ◽

Li Ma ◽

Hong-Mei Xue ◽

Xu-Xin Yang ◽

...

Keyword(s):

Tandem Repeats ◽

Brucella Melitensis ◽

Draft Genome ◽

Geographic Origin ◽

Variable Number ◽

Human Brucellosis ◽

Molecular Characteristics ◽

Whole Genome ◽

Qinghai Province ◽

Variable Number Tandem Repeats

Abstract Background The prevalence of human brucellosis in Qinghai Province of China has been increasing rapidly, with confirmed cases distributed across 31 counties. However, the epidemiology of brucellosis transmission has not been fully elucidated. To characterize the infecting strains isolated from humans, multiple-locus variable-number tandem repeats analysis (MLVA) and whole-genome single-nucleotide polymorphism (SNP)-based approaches were employed. Methods Strains were isolated from two males blood cultures that were confirmed Brucella melitensis positive following biotyping and MLVA. Genomic DNA was extracted from these two strains, and whole-genome sequencing was performed. Next, SNP-based phylogenetic analysis was performed to compare the two strains to 94 B. melitensis strains (complete genome and draft genome) retrieved from online databases. Results The two Brucella isolates were identified as B. melitensis biovar 3 (QH2019001 and QH2019005) following conventional biotyping and were found to have differences in their variable number tandem repeats (VNTRs) using MLVA-16. Phylogenetic examination assigned the 96 strains to five genotype groups, with QH2019001 and QH2019005 assigned to the same group, but different subgroups. Moreover, the QH2019005 strain was assigned to a new subgenotype, IIj, within genotype II. These findings were then combined to determine the geographic origin of the two Brucella strains. Conclusions Utilizing a whole-genome SNP-based approach enabled differences between the two B. melitensis strains to be more clearly resolved, and facilitated the elucidation of their different evolutionary histories. This approach also revealed that QH2019005 is a member of a new subgenotype (IIj) with an ancient origin in the eastern Mediterranean Sea.

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