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2.
Mult Scler ; 29(2): 287-294, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36154526

RESUMO

BACKGROUND: Sexual and physical violence against disabled individuals is widespread and linked to negative public health and social outcomes. The real-world prevalence of abuse in women with multiple sclerosis (MS) has not been well studied. OBJECTIVES: To explore abuse prevalence in a real-world cohort of females with MS attending an academic MS Center. METHODS: Prospective and retrospective abuse data were confidentially collected during neurology clinic visits and extracted from medical records for women attending an academic MS Center. Self-reported and provider-documented prevalence of abuse experiences were correlated with socio-economic and disease-specific factors. RESULTS: In total, 200 women completed prospective questionnaires, and 121 non-overlapping independent health records were retrospectively reviewed. Mean age (SD) was 49.055 (11.39). Seventy-six (38%) reported lifetime abuse incidents; 15% were abused within the previous year. Intimate partners were the most likely verbal (p ⩽ 0.01)) and physical (p = 0.04) abuse perpetrators. Neurologic disability correlated with greater likelihood of verbal abuse (p = 0.021) in prospective cohort. There was no billing or encounter documentation for any form of abuse. CONCLUSION: Intimate partner violence is common in women with MS, correlates with neurologic disability, and is underreported by the health system. Future research needs to focus on abuse detection and mitigation strategies.


Assuntos
Esclerose Múltipla , Maus-Tratos Conjugais , Humanos , Feminino , Maus-Tratos Conjugais/psicologia , Estudos Retrospectivos , Abuso Emocional , Esclerose Múltipla/epidemiologia , Estudos Prospectivos , Prevalência
3.
Vet Microbiol ; 274: 109557, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36088712

RESUMO

Theiler's disease (TD) is a (sub-)acute hepatitis in adult horses and one of the most common causes of acute hepatic failure. Recent findings indicate that equine parvovirus hepatitis (EqPV-H) likely causes TD and that its transmission occurs via iatrogenic and/or natural routes. Following the death of an EqPV-H positive mare with TD, close-contact mares and foals in the same paddock were monitored to evaluate if there was any evidence of EqPV-H. For this purpose, the serum of close contact horses was examined 6 and 42 days after the mare's death for the presence of EqPV-H DNA and changes in liver-associated serum biochemical parameters. The foals had higher EqPV-H viral loads than the mares. Apart from the mare that was euthanized, none of the horses included in this study showed signs of severe disease and nor did they have particularly elevated liver enzymes. Nucleotide sequence analysis revealed no major differences between the viral DNA detected in the serum of the dead mare and any of the in-contact horses. In conclusion, our data confirmed previous findings that horizontal transmission of EqPV-H may occur through close contact between horses.


Assuntos
Hepatite Viral Animal , Hepatite , Doenças dos Cavalos , Infecções por Parvoviridae , Parvovirinae , Parvovirus , Cavalos , Animais , Feminino , Parvovirus/genética , Infecções por Parvoviridae/veterinária , DNA Viral/genética
4.
Analyst ; 145(21): 7000-7008, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-32869782

RESUMO

Miniaturization of electrochemical detection methods for point-of-care-devices is ideal for their integration and use within healthcare environments. Simultaneously, the prolific pathogenic bacteria Pseudomonas aeruginosa poses a serious health risk to patients with compromised immune systems. Recognizing these two factors, a proof-of-concept electrochemical method employing a micro-interface between water and oil (w/o) held at the tip of a pulled borosilicate glass capillary is presented. This method targets small molecules produced by P. aeruginosa colonies as signalling factors that control colony growth in a pseudo-multicellular process known as quorum sensing (QS). The QS molecules of interest are 4-hydroxy-2-heptylquinoline (HHQ) and 2-heptyl-3,4-dihydroxyquinoline (PQS, Pseudomonas quinolone signal). Hydrophobic HHQ and PQS molecules, dissolved in the oil phase, were observed electrochemically to facilitate proton transfer across the w/o interface. This interfacial complexation can be exploited as a facile electrochemical detection method for P. aeruginosa and is advantageous as it does not depend on the redox activity of HHQ/PQS. Interestingly, the limit-of-linearity is reached as [H+] ≈ [ligand]. Density functional theory calculations were performed to determine the proton affinities and gas-phase basicities of HHQ/PQS, as well as elucidate the likely site of stepwise protonation within each molecule.


Assuntos
Prótons , Pseudomonas aeruginosa , Humanos , Percepção de Quorum , Transdução de Sinais
5.
J Org Chem ; 85(4): 2585-2596, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-31971802

RESUMO

Herein, we report a one-pot process that marries mechanistically distinct, traditional cross-coupling reactions with C-H functionalization using the same precatalyst. The reactions proceed in yields of up to 95%, in air, and require no extraneous ligand. The reactions are thought to be facilitated by harnessing the substrate quinoline as an N-ligand, and evidence of the palladium-quinoline interaction is provided by 1H-15N HMBC NMR spectroscopy and X-ray crystallographic structures. Application of the methodology is demonstrated by the quick formation of fluorescent, π-extended frameworks.

6.
Microbiology (Reading) ; 166(2): 169-179, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31860435

RESUMO

In recent years, the alkyl-quinolone molecular framework has already provided a rich source of bioactivity for the development of novel anti-infective compounds. Based on the quorum-sensing signalling molecules 4-hydroxy-2-heptylquinoline (HHQ) and 3,4-dihydroxy-2-heptylquinoline (PQS) from the nosocomial pathogen Pseudomonas aeruginosa, modifications have been developed with markedly enhanced anti-biofilm bioactivity towards important fungal and bacterial pathogens, including Candida albicans and Aspergillus fumigatus. Here we show that antibacterial activity of HHQ against Vibrionaceae is species-specific and it requires an exquisite level of structural fidelity within the alkyl-quinolone molecular framework. Antibacterial activity was demonstrated against the serious human pathogens Vibrio vulnificus and Vibrio cholerae as well as a panel of bioluminescent squid symbiont Allivibrio fischeri isolates. In contrast, Vibrio parahaemolyticus growth and biofilm formation was unaffected in the presence of HHQ and all the structural variants tested. In general, modification to almost all of the molecule except the alkyl-chain end, led to loss of activity. This suggests that the bacteriostatic activity of HHQ requires the concerted action of the entire framework components. The only exception to this pattern was deuteration of HHQ at the C3 position. HHQ modified with a terminal alkene at the quinolone alkyl chain retained bacteriostatic activity and was also found to activate PqsR signalling comparable to the native agonist. The data from this integrated analysis provides novel insights into the structural flexibility underpinning the signalling activity of the complex alkyl-quinolone molecular communication system.


Assuntos
4-Quinolonas/química , 4-Quinolonas/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Pseudomonas aeruginosa/fisiologia , 4-Quinolonas/farmacologia , Alcenos/química , Antibacterianos/farmacologia , Antibiose , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Percepção de Quorum , Transdução de Sinais , Especificidade da Espécie , Relação Estrutura-Atividade , Vibrionaceae/classificação , Vibrionaceae/efeitos dos fármacos , Vibrionaceae/crescimento & desenvolvimento , Vibrionaceae/fisiologia
7.
Int J Mol Sci ; 19(6)2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848961

RESUMO

Cachexia is a metabolic wasting disorder characterized by progressive weight loss, muscle atrophy, fatigue, weakness, and appetite loss. Cachexia is associated with almost all major chronic illnesses including cancer, heart failure, obstructive pulmonary disease, and kidney disease and significantly impedes treatment outcome and therapy tolerance, reducing physical function and increasing mortality. Current cachexia treatments are limited and new pharmacological strategies are needed. Agonists for the growth hormone secretagogue (GHS-R1a), or ghrelin receptor, prospectively regulate the central regulation of appetite and growth hormone secretion, and therefore have tremendous potential as cachexia therapeutics. Non-peptide GHS-R1a agonists are of particular interest, especially given the high gastrointestinal degradation of peptide-based structures, including that of the endogenous ligand, ghrelin, which has a half-life of only 30 min. However, few compounds have been reported in the literature as non-peptide GHS-R1a agonists. In this paper, we investigate the in vitro potential of quinolone compounds to modulate the GHS-R1a in both transfected human cells and mouse hypothalamic cells. These chemically synthesized compounds demonstrate a promising potential as GHS-R1a agonists, shown by an increased intracellular calcium influx. Further studies are now warranted to substantiate and exploit the potential of these novel quinolone-based compounds as orexigenic therapeutics in conditions of cachexia and other metabolic and eating disorders.


Assuntos
Caquexia/tratamento farmacológico , Caquexia/metabolismo , Quinolonas/farmacologia , Quinolonas/uso terapêutico , Receptores de Grelina/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Grelina/metabolismo , Humanos , Camundongos , Transdução de Sinais/efeitos dos fármacos
8.
Sci Rep ; 7(1): 13270, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29038461

RESUMO

The contribution of the gut microbiota to the metabolism of cholesterol is not well understood. In this study, we identify 21 fosmid clones from a human gut microbiome metagenomic library that, when expressed in Escherichia coli, produce halos on LB agar supplemented with 0.01% (w/v) cholesterol (LBC agar). Analysis of 14 of these clones revealed that they all share a fragment of DNA with homology to the genome of Bacteroides vulgatus. The gene responsible for halo production on LBC agar, named choA, was identified as an N-acyltransferase known to produce an acylated glycine molecule called commendamide. In this study we show that commendamide is capable of producing a halo on LBC agar suggesting that this molecule is solubilizing the cholesterol micelles in LBC agar. We also show that commendamide is responsible for the previously described hemolytic activity associated with the choA orthologue in Bacteroides fragilis. A functional analysis of ChoA identified 2 amino acids that are important for commendamide biosynthesis and we present phylogenetic and functional data showing that orthologues of choA are found only in the order Bacteroidales. Therefore, the production of commendamide may be an adaptation to the environments colonized by the Bacteroidales, including the mammalian gut.


Assuntos
Colesterol/metabolismo , Microbioma Gastrointestinal/fisiologia , Glicina/metabolismo , Bacteroides/metabolismo , Bacteroides fragilis/metabolismo , Colesterol/química , Escherichia coli/metabolismo , Microbioma Gastrointestinal/genética , Glicina/química , Hemólise , Filogenia
9.
Org Biomol Chem ; 15(2): 306-310, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27901165

RESUMO

The 'perfect storm' of increasing bacterial antibiotic resistance and a decline in the discovery of new antibiotics, has made it necessary to search for new and innovative strategies to treat bacterial infections. Interruption of bacterial cell-to-cell communication signalling (Quorum Sensing), thus neutralizing virulence in pathogenic bacteria, is a growing area. 2-Alkyl-4-quinolones, HHQ and PQS, play a key role in the quorum sensing circuitry of P. aeruginosa. We report a new set of isosteres of 2-heptyl-6-nitroquinolin-4-one, with alterations at C-3, and evaluate the key structural requirements for agonistic and antagonistic activity in Pseudomonas aeruginosa.


Assuntos
Antibacterianos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Quinolonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antibacterianos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Quinolonas/química , Percepção de Quorum/efeitos dos fármacos , Relação Estrutura-Atividade
10.
Antimicrob Agents Chemother ; 60(10): 5894-905, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27458231

RESUMO

A rapid decline in the development of new antimicrobial therapeutics has coincided with the emergence of new and more aggressive multidrug-resistant pathogens. Pathogens are protected from antibiotic activity by their ability to enter an aggregative biofilm state. Therefore, disrupting this process in pathogens is a key strategy for the development of next-generation antimicrobials. Here, we present a suite of compounds, based on the Pseudomonas aeruginosa 2-heptyl-4(1H)-quinolone (HHQ) core quinolone interkingdom signal structure, that exhibit noncytotoxic antibiofilm activity toward the fungal pathogen Candida albicans In addition to providing new insights into what is a clinically important bacterium-fungus interaction, the capacity to modularize the functionality of the quinolone signals is an important advance in harnessing the therapeutic potential of signaling molecules in general. This provides a platform for the development of potent next-generation small-molecule therapeutics targeting clinically relevant fungal pathogens.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Pseudomonas aeruginosa/química , Bibliotecas de Moléculas Pequenas/farmacologia , 4-Quinolonas/química , 4-Quinolonas/farmacologia , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Candida albicans/fisiologia , Linhagem Celular , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Humanos , Glicoproteínas de Membrana/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Quinolonas/química , Quinolonas/farmacologia , Bibliotecas de Moléculas Pequenas/química
11.
Front Microbiol ; 7: 2074, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28066389

RESUMO

Faced with the continued emergence of antibiotic resistance to all known classes of antibiotics, a paradigm shift in approaches toward antifungal therapeutics is required. Well characterized in a broad spectrum of bacterial and fungal pathogens, biofilms are a key factor in limiting the effectiveness of conventional antibiotics. Therefore, therapeutics such as small molecules that prevent or disrupt biofilm formation would render pathogens susceptible to clearance by existing drugs. This is the first report describing the effect of the Pseudomonas aeruginosa alkylhydroxyquinolone interkingdom signal molecules 2-heptyl-3-hydroxy-4-quinolone and 2-heptyl-4-quinolone on biofilm formation in the important fungal pathogen Aspergillus fumigatus. Decoration of the anthranilate ring on the quinolone framework resulted in significant changes in the capacity of these chemical messages to suppress biofilm formation. Addition of methoxy or methyl groups at the C5-C7 positions led to retention of anti-biofilm activity, in some cases dependent on the alkyl chain length at position C2. In contrast, halogenation at either the C3 or C6 positions led to loss of activity, with one notable exception. Microscopic staining provided key insights into the structural impact of the parent and modified molecules, identifying lead compounds for further development.

12.
Org Biomol Chem ; 13(19): 5537-41, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25880413

RESUMO

The sharp rise in antimicrobial resistance has been matched by a decline in the identification and clinical introduction of new classes of drugs to target microbial infections. Thus new approaches are being sought to counter the pending threat of a post-antibiotic era. In that context, the use of non-growth limiting small molecules, that target virulence behaviour in pathogens, has emerged as a solution with real clinical potential. We have previously shown that two signal molecules (HHQ and PQS) from the nosocomial pathogen Pseudomonas aeruginosa have modulatory activity towards other microorganisms. This current study involves the synthesis and evaluation of analogues of HHQ towards swarming and biofilm virulence behaviour in Bacillus atrophaeus, a soil bacterium and co-inhibitor with P. aeruginosa. Compounds with altered C6-C8 positions on the anthranilate-derived ring of HHQ, display a surprising degree of biological specificity, with certain candidates displaying complete motility inhibition. In contrast, anti-biofilm activity of the parent molecule was completely lost upon alteration at any position indicating a remarkable degree of specificity and delineation of phenotype.


Assuntos
4-Quinolonas/farmacologia , Bacillus/fisiologia , Pseudomonas aeruginosa/química , Percepção de Quorum/efeitos dos fármacos , 4-Quinolonas/química , Bacillus/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Movimento/efeitos dos fármacos , Quinolonas/química , Quinolonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
13.
J Vet Diagn Invest ; 18(1): 18-28, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16566254

RESUMO

This study determined the prevalence of diseases and pathogens associated with mortality or severe morbidity in 72 Ontario beef feedlots in calves that died or were euthanized within 60 days after arrival. Routine pathologic and microbiologic investigations, as well as immunohistochemical staining for detection of bovine viral diarrhea virus (BVDV) antigen, were performed on 99 calves that died or were euthanized within 60 days after arrival. Major disease conditions identified included fibrinosuppurative bronchopneumonia (49%), caseonecrotic bronchopneumonia or arthritis (or both) caused by Mycoplasma bovis (36%), viral respiratory disease (19%), BVDV-related diseases (21%), Histophilus somni myocarditis (8%), ruminal bloat (2%), and miscellaneous diseases (8%). Viral infections identified were BVDV (35%), bovine respiratory syncytial virus (9%), bovine herpesvirus-1 (6%), parainfluenza-3 virus (3%), and bovine coronavirus (2%). Bacteria isolated from the lungs included M. bovis (82%), Mycoplasma arginini (72%), Ureaplasma diversum (25%), Mannheimia haemolytica (27%), Pasteurella multocida (19%), H. somni (14%), and Arcanobacterium pyogenes (19%). Pneumonia was the most frequent cause of mortality of beef calves during the first 2 months after arrival in feedlots, representing 69% of total deaths. The prevalence of caseonecrotic bronchopneumonia caused by M. bovis was similar to that of fibrinosuppurative bronchopneumonia, and together, these diseases were the most common causes of pneumonia and death. M. bovis pneumonia and polyarthritis has emerged as an important cause of mortality in Ontario beef feedlots.


Assuntos
Infecções Bacterianas/veterinária , Complexo Respiratório Bovino/mortalidade , Doenças dos Bovinos/mortalidade , Viroses/veterinária , Animais , Antígenos Virais/análise , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/mortalidade , Complexo Respiratório Bovino/microbiologia , Complexo Respiratório Bovino/virologia , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Vírus da Diarreia Viral Bovina/imunologia , Vírus da Diarreia Viral Bovina/isolamento & purificação , Haemophilus somnus/imunologia , Haemophilus somnus/isolamento & purificação , Imuno-Histoquímica/veterinária , Mannheimia haemolytica/imunologia , Mannheimia haemolytica/isolamento & purificação , Mycoplasma bovis/imunologia , Mycoplasma bovis/isolamento & purificação , Miocardite/microbiologia , Miocardite/mortalidade , Miocardite/veterinária , Ontário/epidemiologia , Vacinas Virais , Viroses/diagnóstico , Viroses/mortalidade
14.
J Vet Diagn Invest ; 18(1): 29-40, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16566255

RESUMO

Mycoplasma bovis is perceived as an emerging cause of mortality in feedlot beef cattle. This study examined the lesions and infectious agents in naturally occurring M. bovis-associated bronchopneumonia and arthritis and the relationship of this condition with bovine viral diarrhea virus (BVDV) infection. Standardized pathologic, immunohistochemical, and microbiologic investigations were conducted on 99 calves that died or were euthanized within 60 days after arrival in 72 feedlots. Cranioventral bronchopneumonia with multiple foci of caseous necrosis was identified in 54 of 99 calves, including 30 with concurrent fibrinosuppurative bronchopneumonia typical of pneumonic pasteurellosis. Mycoplasma bovis was consistently identified in these lesions by culture and immunohistochemistry, but also commonly in healthy lungs and those with pneumonia of other causes. Focal lesions of coagulation necrosis, typical of pneumonic pasteurellosis, were often infected with both Mannheimia haemolytica and M. bovis. Arthritis was present in 25 of 54 (46%) calves with M. bovis pneumonia, and all calves with arthritis had pneumonia. BVDV infection was more common in calves with lesions of bacterial pneumonia than in those dying of other causes, but BVDV infection was not more common in calves with caseonecrotic bronchopneumonia than those with fibrinosuppurative bronchopneumonia. Retrospective analysis identified cases of M. bovis pneumonia in the early 1980s that had milder lesions than the current cases. The findings suggest that, in at least some calves, M. bovis induces caseonecrotic bronchopneumonia within the lesions of pneumonic pasteurellosis.


Assuntos
Artrite Infecciosa/veterinária , Doenças dos Bovinos/microbiologia , Mycoplasma bovis/patogenicidade , Pneumonia por Mycoplasma/veterinária , Animais , Antígenos de Bactérias/análise , Artrite Infecciosa/mortalidade , Artrite Infecciosa/patologia , Doença das Mucosas por Vírus da Diarreia Viral Bovina/complicações , Doença das Mucosas por Vírus da Diarreia Viral Bovina/mortalidade , Doença das Mucosas por Vírus da Diarreia Viral Bovina/patologia , Broncopneumonia/microbiologia , Broncopneumonia/patologia , Broncopneumonia/veterinária , Bovinos , Doenças dos Bovinos/mortalidade , Doenças dos Bovinos/patologia , Doenças Transmissíveis Emergentes/microbiologia , Doenças Transmissíveis Emergentes/mortalidade , Doenças Transmissíveis Emergentes/veterinária , Imuno-Histoquímica/veterinária , Mannheimia haemolytica/isolamento & purificação , Mycoplasma bovis/imunologia , Mycoplasma bovis/isolamento & purificação , Pasteurelose Pneumônica/microbiologia , Pasteurelose Pneumônica/mortalidade , Pneumonia por Mycoplasma/mortalidade , Pneumonia por Mycoplasma/patologia , Estudos Retrospectivos
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