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1.
Dalton Trans ; 53(10): 4637-4642, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38354056

ABSTRACT

A series of mono/bimetallic isostructural hybrid tetraborates of the general formula [ZnxCo(1-x)(1,3-dap)B4O7] has been prepared using a solvothermal method. Their adsorption/desorption curves for H2O and D2O demonstrate that these materials have a stronger affinity for H2O than for D2O and enrich the D2O content of D2O/H2O mixtures.

2.
Molecules ; 28(19)2023 Sep 29.
Article in English | MEDLINE | ID: mdl-37836710

ABSTRACT

Two substituted phosphonium tetrahydoxidohexaoxidopentaborate(1-) salts, [iPrPPh3][B5O6(OH)4]·3.5H2O (1) and [MePPh3][B5O6(OH)4]·B(OH)3·0.5H2O (2), were prepared by templated self-assembly processes with good yields by crystallization from basic methanolic aqueous solutions primed with B(OH)3 and the appropriate phosphonium cation. Salts 1 and 2 were characterized by spectroscopic (NMR and IR) and thermal (TGA/DSC) analysis. Salts 1 and 2 were thermally decomposed in air at 800 °C to glassy solids via the anhydrous phosphonium polyborates that are formed at lower temperatures (<300 °C). BET analysis of the anhydrous and pyrolysed materials indicated they were non-porous with surface areas of 0.2-2.75 m2/g. Rhe recrystallization of 1 and 2 from aqueous solution afforded crystals suitable for single-crystal XRD analyses. The structure of 1 comprises alternating cationic/anionic layers with the H2O/pentaborate(1-) planes held together by H-bonds. The cationic planes have offset face-to-face (off) and vertex-to-face (vf) aromatic ring interactions with the iPr groups oriented towards the pentaborate(1-)/H2O layers. The anionic lattice in 2 is expanded by the inclusion of B(OH)3 molecules to accommodate the large cations; this results in the formation of a stacked pentaborate(1-)/B(OH)3 structure with channels occupied by the cations. The cations within the channels have vf, ef (edge-to-face), and off phenyl embraces. Both H-bonding and phenyl embrace interactions are important in stabilizing these two solid-state structures.

3.
Molecules ; 28(7)2023 Apr 06.
Article in English | MEDLINE | ID: mdl-37050036

ABSTRACT

The synthesis and characterization of six new substituted guanidium tetrahydroxidohexaoxidopentaborate(1-) salts are reported: [C(NH2)2(NHMe)][B5O6(OH)4]·H2O (1), [C(NH2)2(NH{NH2})][B5O6(OH)4] (2), [C(NH2)2(NMe2)][B5O6(OH)4] (3), [C(NH2)(NMe2)2][B5O6(OH)4] (4), [C(NHMe)(NMe2)2][B5O6(OH)4]·B(OH)3 (5), and [TBDH][B5O6(OH)4] (6) (TBD = 1,5,7-triazabicyclo [4.4.0]dec-5-ene). Compounds 1-6 were prepared as crystalline salts from basic aqueous solution via self-assembly processes from B(OH)3 and the appropriate substituted cation. Compounds 1-6 were characterized by spectroscopic (NMR and IR) and by single-crystal XRD studies. A thermal (TGA) analysis on compounds 1-3 and 6 demonstrated that they thermally decomposed via a multistage process to B2O3 at >650 °C. The low temperature stage (<250 °C) was endothermic and corresponded to a loss of H2O. Reactant stoichiometry, solid-state packing, and H-bonding interactions are all important in assembling these structures. An analysis of H-bonding motifs in known unsubstituted guanidinium salts [C(NH2)3]2[B4O5(OH)4]·2H2O, [C(NH2)3][B5O6(OH)4]·H2O, and [C(NH2)3]3[B9O12(OH)6] and in compounds 1-6 revealed that two important H-bonding R22(8) motifs competed to stabilize the observed structures. The guanidinium cation formed charge-assisted pincer cation-anion H-bonded rings as a major motif in [C(NH2)3]2[B4O5(OH)4]·2H2O and [C(NH2)3]3[B9O12(OH)6], whereas the anion-anion ring motif was dominant in [C(NH2)3][B5O6(OH)4]·H2O and in compounds 1-6. This behaviour was consistent with the stoichiometry of the salt and packing effects also strongly influencing their solid-state structures.

5.
Microb Genom ; 8(2)2022 02.
Article in English | MEDLINE | ID: mdl-35166652

ABSTRACT

The Integration Host Factor (IHF) is a heterodimeric nucleoid-associated protein that plays roles in bacterial nucleoid architecture and genome-wide gene regulation. The ihfA and ihfB genes encode the subunits and are located 350 kbp apart, in the Right replichore of the Salmonella chromosome. IHF is composed of one IhfA and one IhfB subunit. Despite this 1 : 1 stoichiometry, MS revealed that IhfB is produced in 2-fold excess over IhfA. We re-engineered Salmonella to exchange reciprocally the protein-coding regions of ihfA and ihfB, such that each relocated protein-encoding region was driven by the expression signals of the other's gene. MS showed that in this 'rewired' strain, IhfA is produced in excess over IhfB, correlating with enhanced stability of the hybrid ihfB-ihfA mRNA that was expressed from the ihfB promoter. Nevertheless, the rewired strain grew at a similar rate to the wild-type and was similar in competitive fitness. However, compared to the wild-type, it was less motile, had growth-phase-specific reductions in SPI-1 and SPI-2 gene expression, and was engulfed at a higher rate by RAW macrophage. Our data show that while exchanging the physical locations of its ihf genes and the rewiring of their regulatory circuitry are well tolerated in Salmonella, genes involved in the production of type 3 secretion systems exhibit dysregulation accompanied by altered phenotypes.


Subject(s)
Integration Host Factors/genetics , Salmonella typhimurium/genetics , Salmonella typhimurium/metabolism , Base Sequence , Gene Expression Regulation, Bacterial , Genome, Bacterial , Integration Host Factors/metabolism , Promoter Regions, Genetic , Serogroup , Virulence/genetics
6.
Am J Infect Control ; 50(8): 947-953, 2022 08.
Article in English | MEDLINE | ID: mdl-35065149

ABSTRACT

BACKGROUND: Ultraviolet germicidal irradiation (UVGI) technologies have emerged as a promising adjunct to manual cleaning, however, their potential to shorten cleaning times remains unexplored. METHODS: A <10-minute disinfection procedure was developed using a robotic UVGI platform. The efficacy and time to perform the UVGI procedure in a CT scan treatment room was compared with current protocols involving manual disinfection using biocides. For each intervention, environmental samples were taken at 12 locations in the room before and after disinfection on seven distinct occasions. RESULTS: The mean UVC dose at each sample location was found to be 13.01 ± 4.36 mJ/cm2, which exceeded published UVC thresholds for achieving log reductions of many common pathogens. Significant reductions in microbial burden were measured after both UVGI (P≤.001) and manual cleaning (P≤.05) conditions, with the UVGI procedure revealing the largest effect size (r = 0.603). DISCUSSION: These results support the hypothesis that automated deployments of UVGI technology can lead to germicidal performance that is comparable with, and potentially better than, current manual cleaning practices. CONCLUSIONS: Our findings provide early evidence that the incorporation of automated UVGI procedures into cleaning workflow could reduce turnaround times in radiology, and potentially other hospital settings.


Subject(s)
Radiology , Robotics , Disinfection/methods , Hospitals , Humans , Ultraviolet Rays
7.
Molecules ; 26(13)2021 Jun 22.
Article in English | MEDLINE | ID: mdl-34206683

ABSTRACT

Crystalline materials containing hybrid inorganic-organic metal borates (complexes with oxidoborate ligands) display a variety of novel framework building blocks. The structural aspects of these hybrid metallaoxidoborates containing Cd(II), Co(II), Cu(II), Ga(III), In(III), Mn(II), Ni(II) or Zn(II) metal centers are discussed in this review. The review describes synthetic approaches to these hybrid materials, their physical properties, their spectroscopic properties and their potential applications.

8.
Cancer Res ; 80(24): 5633-5641, 2020 12 15.
Article in English | MEDLINE | ID: mdl-33087322

ABSTRACT

Dendritic cells (DC) play an essential role in innate immunity and radiation-elicited immune responses. LGP2 is a RIG-I-like receptor involved in cytoplasmic RNA recognition and antiviral responses. Although LGP2 has also been linked to cell survival of both tumor cells and T cells, the role of LGP2 in mediating DC function and antitumor immunity elicited by radiotherapy remains unclear. Here, we report that tumor DCs are linked to the clinical outcome of patients with breast cancer who received radiotherapy, and the presence of DC correlates with gene expression of LGP2 in the tumor microenvironment. In preclinical models, host LGP2 was essential for optimal antitumor control by ionizing radiation (IR). The absence of LGP2 in DC dampened type I IFN production and the priming capacity of DC. In the absence of LGP2, MDA5-mediated activation of type I IFN signaling was abrogated. The MDA5/LGP2 agonist high molecular weight poly I:C improved the antitumor effect of IR. This study reveals a previously undefined role of LGP2 in host immunity and provides a new strategy to improve the efficacy of radiotherapy. SIGNIFICANCE: These findings reveal an essential role of LGP2 in promoting antitumor immunity after radiotherapy and provide a new strategy to enhance radiotherapy.


Subject(s)
Dendritic Cells/pathology , RNA Helicases/genetics , Triple Negative Breast Neoplasms/radiotherapy , Animals , CD8-Positive T-Lymphocytes , Cell Line, Tumor , DEAD Box Protein 58/genetics , DEAD Box Protein 58/metabolism , Dendritic Cells/radiation effects , Female , Gene Expression Regulation, Neoplastic , Humans , Interferon-Induced Helicase, IFIH1/genetics , Interferon-Induced Helicase, IFIH1/metabolism , Interferon-gamma/metabolism , Mice, Inbred C57BL , Mice, Transgenic , Poly I-C/pharmacology , RNA Helicases/metabolism , Radiation, Ionizing , Receptors, Immunologic/genetics , Receptors, Immunologic/metabolism , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/mortality
9.
mBio ; 11(5)2020 09 08.
Article in English | MEDLINE | ID: mdl-32900812

ABSTRACT

The Fis nucleoid-associated protein controls the expression of a large and diverse regulon of genes in Gram-negative bacteria. Fis production is normally maximal in bacteria during the early exponential phase of batch culture growth, becoming almost undetectable by the onset of stationary phase. We tested the effect on the Fis regulatory network in Salmonella of moving the complete fis gene from its usual location near the origin of chromosomal replication to the position normally occupied by the dps gene in the right macrodomain of the chromosome, and vice versa, creating the gene exchange (GX) strain. In a parallel experiment, we tested the effect of rewiring the Fis regulatory network by placing the fis open reading frame under the control of the stationary-phase-activated dps promoter at the dps genetic location within the right macrodomain, and vice versa, creating the open reading frame exchange (OX) strain. Chromatin immunoprecipitation sequencing (ChIP-seq) was used to measure global Fis protein binding levels and to determine gene expression patterns. Strain GX showed few changes compared with the wild type, although we did detect increased Fis binding at Ter, accompanied by reduced binding at Ori. Strain OX displayed a more pronounced version of this distorted Fis protein-binding pattern together with numerous alterations in the expression of genes in the Fis regulon. OX, but not GX, had a reduced ability to infect cultured mammalian cells. These findings illustrate the inherent robustness of the Fis regulatory network with respect to the effects of rewiring based on gene repositioning alone and emphasize the importance of fis expression signals in phenotypic determination.IMPORTANCE We assessed the impact on Salmonella physiology of reciprocally translocating the genes encoding the Fis and Dps nucleoid-associated proteins (NAPs) and of inverting their growth-phase production patterns such that Fis was produced in stationary phase (like Dps) and Dps was produced in exponential phase (like Fis). Changes to peak binding of Fis were detected by ChIP-seq on the chromosome, as were widespread impacts on the transcriptome, especially when Fis production mimicked Dps production. Virulence gene expression and the expression of a virulence phenotype were altered. Overall, these radical changes to NAP gene expression were well tolerated, revealing the robust and well-buffered nature of global gene regulation networks in the bacterium.


Subject(s)
Bacterial Proteins/genetics , Gene Expression Regulation, Bacterial , Gene Regulatory Networks , Genes, Bacterial/genetics , Salmonella typhimurium/growth & development , Salmonella typhimurium/genetics , Bacterial Proteins/metabolism , Genes, Bacterial/physiology , Genome, Bacterial , Promoter Regions, Genetic , Regulon , Salmonella typhimurium/physiology , Sequence Analysis, RNA , Virulence
10.
Proc Natl Acad Sci U S A ; 117(36): 22423-22429, 2020 09 08.
Article in English | MEDLINE | ID: mdl-32848073

ABSTRACT

Metastases are the cause of the vast majority of cancer deaths. In the metastatic process, cells migrate to the vasculature, intravasate, extravasate, and establish metastatic colonies. This pattern of spread requires the cancer cells to change shape and to navigate tissue barriers. Approaches that block this mechanical program represent new therapeutic avenues. We show that 4-hydroxyacetophenone (4-HAP) inhibits colon cancer cell adhesion, invasion, and migration in vitro and reduces the metastatic burden in an in vivo model of colon cancer metastasis to the liver. Treatment with 4-HAP activates nonmuscle myosin-2C (NM2C) (MYH14) to alter actin organization, inhibiting the mechanical program of metastasis. We identify NM2C as a specific therapeutic target. Pharmacological control of myosin isoforms is a promising approach to address metastatic disease, one that may be readily combined with other therapeutic strategies.


Subject(s)
Acetophenones/pharmacology , Actomyosin/metabolism , Cytoskeleton , Neoplasm Metastasis/physiopathology , Actins/metabolism , Animals , Cell Adhesion/drug effects , Cell Movement/drug effects , Colorectal Neoplasms/metabolism , Cytoskeleton/drug effects , Cytoskeleton/metabolism , Female , HCT116 Cells , Humans , Mice , Mice, Nude
11.
Front Robot AI ; 7: 590306, 2020.
Article in English | MEDLINE | ID: mdl-33501347

ABSTRACT

The importance of infection control procedures in hospital radiology departments has become increasingly apparent in recent months as the impact of COVID-19 has spread across the world. Existing disinfectant procedures that rely on the manual application of chemical-based disinfectants are time consuming, resource intensive and prone to high degrees of human error. Alternative non-touch disinfection methods, such as Ultraviolet Germicidal Irradiation (UVGI), have the potential to overcome many of the limitations of existing approaches while significantly improving workflow and equipment utilization. The aim of this research was to investigate the germicidal effectiveness and the practical feasibility of using a robotic UVGI device for disinfecting surfaces in a radiology setting. We present the design of a robotic UVGI platform that can be deployed alongside human workers and can operate autonomously within cramped rooms, thereby addressing two important requirements necessary for integrating the technology within radiology settings. In one hospital, we conducted experiments in a CT and X-ray room. In a second hospital, we investigated the germicidal performance of the robot when deployed to disinfect a CT room in <15 minutes, a period which is estimated to be 2-4 times faster than current practice for disinfecting rooms after infectious (or potentially infectious) patients. Findings from both test sites show that UVGI successfully inactivated all of measurable microbial load on 22 out of 24 surfaces. On the remaining two surfaces, UVGI reduced the microbial load by 84 and 95%, respectively. The study also exposes some of the challenges of manually disinfecting radiology suites, revealing high concentrations of microbial load in hard-to-reach places. Our findings provide compelling evidence that UVGI can effectively inactivate microbes on commonly touched surfaces in radiology suites, even if they were only exposed to relatively short bursts of irradiation. Despite the short irradiation period, we demonstrated the ability to inactivate microbes with more complex cell structures and requiring higher UV inactivation energies than SARS-CoV-2, thus indicating high likelihood of effectiveness against coronavirus.

12.
Molecules ; 25(1)2019 Dec 23.
Article in English | MEDLINE | ID: mdl-31877919

ABSTRACT

The synthesis of a number of pentaborate(1-) salts from cations arising from N-substituted α,α-, α,ß-, and α,γ-diaminoalkanes has been attempted in aqueous solution from B(OH)3 and the appropriate diammine in a 10:1 ratio. Despite relatively mild work-up conditions the pentaborate(1-) salts prepared were not always as anticipated and the following compounds were isolated in good yield: [Me2NH(CH2)2NHMe2][B5O6(OH)4]2 (1), [Et2NH(CH2)2NHEt2][B5O6(OH)4]2 (2), [Et2NH2][B5O6(OH)4] (3), [Me2NH2][B5O6(OH)4] (4), [Me2NH(CH2)3NHMe2][B5O6(OH)4]2 (5), [Et2NH(CH2)3NHEt2][B5O6(OH)4]2 (6), [Me3NCH2CH=CH2][B5O6(OH)4] (7), and [Me3N(CH2)3NMe3] [B5O6(OH)4]2.0.5H2O (8). The tetraborate(2-) salt, [Me3N(CH2)2NMe3][B4O5(OH)4].2B(OH)3.2H2O (9) was obtained in moderate yield (41%) from a 3:1 reaction of B(OH)3 with [Me3N(CH2)2NMe3](OH)2. All compounds were characterized by spectroscopy (1H, 11B, 13C NMR and IR) and thermal gravimetric analysis (TGA). BET analysis on materials derived thermally from selected samples (1, 2, 6, 7) all had porosities of < 1 m2/g, demonstrating that they were non-porous. Single-crystal XRD structures were obtained for 2, 3, 7, 8 and 9 and all contain extensive H-bonded polyborate lattices.


Subject(s)
Ammonium Compounds/chemistry , Borates/chemistry , Salts/chemistry , Cations/chemistry , Hydrogen Bonding , Magnetic Resonance Spectroscopy , Molecular Structure , Sodium Chloride/chemistry , Water/chemistry
13.
Nat Commun ; 10(1): 3959, 2019 09 02.
Article in English | MEDLINE | ID: mdl-31477729

ABSTRACT

Successful combinations of radiotherapy and immunotherapy depend on the presence of live T cells within the tumor; however, radiotherapy is believed to damage T cells. Here, based on longitudinal in vivo imaging and functional analysis, we report that a large proportion of T cells survive clinically relevant doses of radiation and show increased motility, and higher production of interferon gamma, compared with T cells from unirradiated tumors. Irradiated intratumoral T cells can mediate tumor control without newly-infiltrating T cells. Transcriptomic analysis suggests T cell reprogramming in the tumor microenvironment and similarities with tissue-resident memory T cells, which are more radio-resistant than circulating/lymphoid tissue T cells. TGFß is a key upstream regulator of T cell reprogramming and contributes to intratumoral Tcell radio-resistance. These findings have implications for the design of radio-immunotherapy trials in that local irradiation is not inherently immunosuppressive, and irradiation of multiple tumors might optimize systemic effects of radiotherapy.


Subject(s)
Immunotherapy/methods , Lymphocytes, Tumor-Infiltrating/metabolism , Neoplasms, Experimental/therapy , Radiotherapy/methods , Animals , Cell Line, Tumor , Cell Movement/genetics , Cell Survival/genetics , Combined Modality Therapy , Gene Expression Profiling/methods , Interferon-gamma/immunology , Interferon-gamma/metabolism , Lymphocytes, Tumor-Infiltrating/immunology , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Neoplasms, Experimental/genetics , Neoplasms, Experimental/immunology , Radiation Tolerance/genetics
14.
Healthc Q ; 21(1): 19-24, 2018 Apr.
Article in English | MEDLINE | ID: mdl-30051811

ABSTRACT

BACKGROUND: Effective patient relations can improve the patient experience and the safe delivery of care. Recent Ontario policy and legislative changes have increased accountabilities for healthcare organizations and expanded Health Quality Ontario's mandate to measure and report on patient relations. The purpose of this pilot project was to support improved care by validating standardized measures, data submission processes and prototype reporting of patient relations indicators for the hospital, home and community care and long-term care sectors across Ontario. METHODS: Health Quality Ontario identified potential indicators and best practices by performing a comprehensive environmental scan and consulting with experts, including patients and caregivers. It shortlisted indicators based on alignment to best practices and Ontario legislative requirements. A provincial advisory group then used a modified Delphi process to prioritize and recommend five patient relations indicators for province-wide measurement and comparative public reporting. Through the pilot project, these indicators were validated using facility-level data for fiscal year (FY) 2015-2016 from 29 hospitals, home and community care organizations and long-term care homes across Ontario. RESULTS: In June 2016, Health Quality Ontario recruited 34 organizations for the pilot project. Twenty-nine sites successfully submitted summary-level data on patient relations indicators. More than 90% of the required data were retrieved from existing papers or electronic systems. All sites mapped facility-level "complaint" and "action taken" categories to the provincial standardized categories. Across the three health sectors, "care and treatment" was the top complaint category in FY 2015-2016. CONCLUSIONS: This pilot project reinforced the value of measuring patient relations and reporting feedback to support facility- and system-level improvement. The pilot sites and provincial advisory group recommended phased implementation. This would permit healthcare organizations to standardize data collection and align with provincial indicators and categories. The next step would be voluntary data submission to Health Quality Ontario in advance of any reporting. To facilitate voluntary implementation, Health Quality Ontario included one indicator, "complaints acknowledged," in the annual Quality Improvement Plans beginning in FY 2018-2019. This will allow organizations to monitor and report on the percentage of complaints acknowledged within 2, 5 and 10 days. Implementation will evolve based on input from patients, health sector organizations, Local Health Integration Networks and the Patient Ombudsman.


Subject(s)
Patient Safety/standards , Patient Satisfaction , Quality Indicators, Health Care/organization & administration , Community Networks/standards , Home Care Services/standards , Hospitals/standards , Humans , Long-Term Care/standards , Ontario , Pilot Projects , Risk Management
15.
BMJ Open ; 8(1): e018272, 2018 01 21.
Article in English | MEDLINE | ID: mdl-29358430

ABSTRACT

OBJECTIVE: This study explores the relationship between health access barriers and diabetes in an urban First Nations population in Canada. DESIGN: Data from a self-identified urban First Nations population were collected using respondent-driven sampling (RDS). As no clear approach for regression modelling of RDS data is available, two logistic regression modelling approaches, including survey-based logistic and generalised linear mixed models, were used to explore the relationship between diabetes and health barriers of interest, including access to healthcare, food, housing and socioeconomic factors. SETTING: Hamilton, Ontario, Canada. PARTICIPANTS: This cross-sectional study used data collected from the Our Health Counts study, in partnership with the De dwa da dehs nye>s Aboriginal Health Centre, which recruited 554 First Nations adults living in Hamilton using RDS. RESULTS: After adjusting for covariates, multivariable regression techniques showed a statistically significant relationship between a self-reported diagnosis of diabetes and a lack of culturally appropriate care among urban First Nations peoples (OR: 12.70, 95% CI 2.52 to 57.91). There was also a trend towards a relationship between diabetes and not having a doctor available in the area, feeling that healthcare provided was inadequate and a lack of available healthcare services in the area. CONCLUSIONS: Urban First Nations peoples who felt the health service they received was not culturally appropriate were more likely to have diabetes, compared with those who did not feel the service they received was culturally inappropriate. Establishing more healthcare services that integrate First Nations cultures and traditions could improve access to care and the course of treatment for urban First Nations peoples living with diabetes.


Subject(s)
Diabetes Mellitus/ethnology , Diabetes Mellitus/therapy , Health Services Accessibility/statistics & numerical data , Indians, North American , Adolescent , Adult , Aged , Cross-Sectional Studies , Exercise , Female , Humans , Logistic Models , Male , Middle Aged , Multivariate Analysis , Ontario/epidemiology , Self Report , Socioeconomic Factors , Urban Population , Young Adult
16.
J Clust Sci ; 28(4): 2087-2095, 2017.
Article in English | MEDLINE | ID: mdl-32226267

ABSTRACT

The non-metal cation pentaborate(1-) salt [p-H2NC6H4CH2NH3][B5O6(OH)4]·1/2H2O (1) was synthesised from B(OH)3 and p-H2NC6H4CH2NH2 and crystallized from aqueous solution. Compound 1 was characterized by thermal (TGA/DSC), spectroscopic (IR, NMR) and single-crystal X-ray diffraction methods and it was found to crystallize in the non-centrosymmetric point group P21. Powder SHG measurements on 1 and some related alkylammonium pentaborate salts, [NH3CMe2(CH2OH)][B5O6(OH)4], [NH3CMe(CH2OH)2][B5O6(OH)4] and [NH3CHMeCH2OH][B5O6(OH)4], a substituted imidazolium salt, [1,2,3-Me3C3H2N2][B5O6(OH)4], a substituted piperidinium salt, [(CH2)5NH(CH2CH2OH)][B5O6(OH)4], and a substituted pyrrolidinium salt, [S-(+)-2-(HOCH2)C4H7NH2][B5O6(OH)4], were determined. Compound 1 and all compounds, except [1,2,3-Me3C3H2N2][B5O6(OH)4], showed some weak SHG activity with SHG efficiencies of 0.1-0.2 relative to that of KH2PO4 (KDP).

17.
Appl Environ Microbiol ; 82(14): 4288-4298, 2016 07 15.
Article in English | MEDLINE | ID: mdl-27208129

ABSTRACT

UNLABELLED: Antimicrobial peptides offer potential as novel therapeutics to combat food spoilage and poisoning caused by pathogenic and nonpathogenic bacteria. Our previous studies identified the peptide human beta-defensin 3 (HBD3) as a potent antimicrobial agent against a wide range of beer-spoiling bacteria. Thus, HBD3 is an excellent candidate for development as an additive to prevent food and beverage spoilage. To expand the repertoire of peptides with antimicrobial activity against bacteria associated with food spoilage and/or food poisoning, we carried out an in silico discovery pipeline to identify peptides with structure and activity similar to those of HBD3, focusing on peptides of plant origin. Using a standardized assay, we compared the antimicrobial activities of nine defensin-like plant peptides to the activity of HBD3. Only two of the peptides, fabatin-2 and Cp-thionin-2, displayed antimicrobial activity; however, the peptides differed from HBD3 in being sensitive to salt and were thermostable. We also compared the activities of several ultrashort peptides to that of HBD3. One of the peptides, the synthetic tetrapeptide O3TR, displayed biphasic antimicrobial activity but had a narrower host range than HBD3. Finally, to determine if the peptides might act in concert to improve antimicrobial activity, we compared the activities of the peptides in pairwise combinations. The plant defensin-like peptides fabatin-2 and Cp-thionin-2 displayed a synergistic effect with HBD3, while O3TR was antagonistic. Thus, some plant defensin-like peptides are effective antimicrobials and may act in concert with HBD3 to control bacteria associated with food spoilage and food poisoning. IMPORTANCE: Food spoilage and food poisoning caused by bacteria can have major health and economic implications for human society. With the rise in resistance to conventional antibiotics, there is a need to identify new antimicrobials to combat these outbreaks in our food supply. Here we screened plant peptide databases to identify peptides that share structural similarity with the human defensin peptide HBD3, which has known antimicrobial activity against food-spoiling bacteria. We show that two of the plant peptides display antimicrobial activity against bacteria associated with food spoilage. When combined with HBD3, the peptides are highly effective. We also analyzed the activity of an easily made ultrashort synthetic peptide, O3TR. We show that this small peptide also displays antimicrobial activity against food-spoiling bacteria but is not as effective as HBD3 or the plant peptides. The plant peptides identified are good candidates for development as natural additives to prevent food spoilage.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Defensins/pharmacology , Food Microbiology , Oligopeptides/pharmacology , Plant Proteins/pharmacology , Plants/chemistry , Computational Biology , Defensins/genetics , Defensins/isolation & purification , Drug Discovery , Drug Synergism , Microbial Sensitivity Tests , Oligopeptides/genetics , Oligopeptides/isolation & purification , Plant Proteins/genetics , Plant Proteins/isolation & purification
18.
BMC Geriatr ; 15: 9, 2015 Feb 11.
Article in English | MEDLINE | ID: mdl-25887627

ABSTRACT

BACKGROUND: The incidence of Alzheimer's disease is increasing as the global population ages. Given the limited success of pharmaceuticals in preventing this disease, a greater emphasis on non-pharmaceutical approaches is needed. The aim of this study was to quantify the association between Alzheimer's disease and physical activity in older adults over the age of 65 years. METHODS: A meta-analytic approach was used to determine if physical activity reduced the risk of Alzheimer's disease in individuals 65 years or older. Some evidence indicates that physical activity may improve cognitive function in older adults, while other evidence is inconclusive. The purpose of this study was to examine if prevention of Alzheimer's disease is possible if started at a later age. The precise brain changes that occur with the onset of Alzheimer's disease are not fully known, and therefore may still be influenced by preventative measures even in advancing age. Determining if physical activity can inhibit the onset of the disease at any age may motivate individuals to adopt an "it's never too late" mentality on preventing the onset of this debilitating disease. Longitudinal studies of participants who were 65 years or older at baseline were included. A total of 20,326 participants from nine studies were included in this analysis. RESULTS: The fixed effects risk ratio is estimated as 0.61 (95% CI 0.52-0.73) corresponding to a statistically significant overall reduction in risk of Alzheimer's disease in physically active older adults compared to their non-active counterparts. CONCLUSION: Physical activity was associated with a reduced risk of Alzheimer's disease in adults over the age of 65 years. Given the limited treatment options, greater emphasis should be paid to primary prevention through physical activity amongst individuals at high-risk of Alzheimer's disease, such as those with strong genetic and family history.


Subject(s)
Alzheimer Disease/prevention & control , Motor Activity , Aged , Aged, 80 and over , Alzheimer Disease/psychology , Female , Humans , Male , Prospective Studies
19.
Dalton Trans ; 44(15): 7032-40, 2015 Apr 21.
Article in English | MEDLINE | ID: mdl-25785672

ABSTRACT

The synthesis and characterization of a series of pentaborate(1-) salts of substituted pyrrolidinium cations [C4H8NH2][B5O6(OH)4] (), [C4H8NMe2][B5O6(OH)4] () [C4H8NMeH][B5O6(OH)4] (), [(2-CH2OH)C4H7NH2][B5O6(OH)4] () is reported. All compounds were characterized by single-crystal XRD studies with (1/2CH3COCH3) and (1/2H2O) solvated. TGA/DSC analysis of the pentaborates showed that they thermally decomposed in air at 800 °C to 2.5 B2O3, in a 2 step process involving dehydration (<250 °C) and oxidative decomposition (250-600 °C). BET analysis of materials derived thermally from the pentaborates and had internal porosities of <1 m(2) g(-1), indicating they were non-porous. All compounds show extensive supramolecular H-bonded anionic lattices. H-bond interactions are described in detail and motifs found in these and in other pentaborate structures have been examined and modelled by DFT calculations. These calculations confirm that H-bonds interactions in pentaborates are moderately strong (ca. -10 to -21 kJ mol(-1)) and are likely to dominate the energetics of their templated syntheses.

20.
Inorg Chem ; 54(2): 412-4, 2015 Jan 20.
Article in English | MEDLINE | ID: mdl-25531386

ABSTRACT

The synthesis and X-ray diffraction structure of [Co(en)3][B5O6(OH)4][B8O10(OH)6]·5H2O (1) are reported. Compound 1 arises through a selective-templating process from a Dynamic Combinatorial Library of polyborate anions. Compound 1 contains two different polyborate species, with [B8O10(OH)6](2-) being particularly novel. It is comprised of fused tetraborate and pentaborate anions with a 4-coordinate B atom and a 3-coordinate O atom in common.

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