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Objective: To describe the differential diagnosis, diagnosis, and chiropractic management of a case of chronic upper extremity paresthesia. Clinical features: A 24-year-old woman presented with recent neck stiffness, along with a primary complaint of chronic upper extremity paresthesia and hand weakness of insidious onset. Intervention and outcome: Results of previous electro-diagnostic and advanced imaging studies were combined with clinical assessment to diagnose thoracic outlet syndrome (TOS). Discontinuing after five weeks of chiropractic management, the patient reported significant improvement of paresthesia but less improvement of her hand weakness. Summary: Several etiologies can give rise to symptoms in common with TOS. It is imperative to rule out mimicking conditions. A battery of clinical orthopedic tests has been proposed in the literature for the diagnosis of TOS but with reported questionable validity. As a result, TOS is mostly a diagnosis of exclusion. Chiropractic treatment shows potential for effective management of TOS, but research is required.
Objectif: Décrire le diagnostic différentiel, le diagnostic et la prise en charge chiropratique d'un cas de paresthésie chronique des membres supérieurs. Caractéristiques cliniques: Une femme de 24 ans s'est présentée avec une raideur de la nuque récente, ainsi qu'avec une plainte primaire de paresthésie chronique des membres supérieurs et de faiblesse de la main d'apparition insidieuse. Intervention et résultats: Les résultats d'un électrodiagnostic antérieur et d'examens d'imagerie avancée ont été combinés à une évaluation clinique pour diagnostiquer un syndrome du défilé thoraco-brachial. Après cinq semaines de traitement chiropratique, la patiente a signalé une amélioration significative de ses paresthésies, mais une amélioration moindre de la faiblesse de sa main. Résumé: Plusieurs étiologies peuvent donner lieu à des symptômes communs avec le syndrome du défilé thoraco-brachial. Il est impératif d'exclure les affections mimétiques. Une batterie de tests orthopédiques cliniques a été proposée dans la littérature pour le diagnostic du syndrome du défilé thoraco-brachial, mais leur validité est discutable. Par conséquent, le syndrome du défilé thoraco-brachial est le plus souvent un diagnostic d'exclusion. La chiropratique est susceptible de permettre une prise en charge efficace du syndrome du défilé thoraco-brachial, mais des recherches s'imposent.
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It is essential to understand the mechanisms by which a toxicant is capable of poisoning the bacterial cell. The mechanism of action of many biocides and toxins, including numerous ubiquitous compounds, is not fully understood. For example, despite the widespread clinical and commercial use of silver (Ag), the mechanisms describing how this metal poisons bacterial cells remains incomplete. To advance our understanding surrounding the antimicrobial action of Ag, we performed a chemical genetic screen of a mutant library of Escherichia coli—the Keio collection, in order to identify Ag sensitive or resistant deletion strains. Indeed, our findings corroborate many previously established mechanisms that describe the antibacterial effects of Ag, such as the disruption of iron-sulfur clusters containing proteins and certain cellular redox enzymes. However, the data presented here demonstrates that the activity of Ag within the bacterial cell is more extensive, encompassing genes involved in cell wall maintenance, quinone metabolism and sulfur assimilation. Altogether, this study provides further insight into the antimicrobial mechanism of Ag and the physiological adaption of E. coli to this metal.
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Nitrosative stress results from an increase in reactive nitrogen species (RNS) within the cell. Though the RNS - nitric oxide (·NO) and peroxynitrite (ONOO-) - play pivotal physiological roles, at elevated concentrations, these moieties can be poisonous to both prokaryotic and eukaryotic cells alike due to their capacity to disrupt a variety of essential biological processes. Numerous microbes are known to adapt to nitrosative stress by elaborating intricate strategies aimed at neutralizing RNS. In this review, we will discuss both the enzymatic systems dedicated to the elimination of RNS as well as the metabolic networks that are tailored to generate RNS-detoxifying metabolites - α-keto-acids. The latter has been demonstrated to nullify RNS via non-enzymatic decarboxylation resulting in the production of a carboxylic acid, many of which are potent signaling molecules. Furthermore, as aerobic energy production is severely impeded during nitrosative stress, alternative ATP-generating modules will be explored. To that end, a holistic understanding of the molecular adaptation to nitrosative stress, reinforces the notion that neutralization of toxicants necessitates significant metabolic reconfiguration to facilitate cell survival. As the alarming rise in antimicrobial resistant pathogens continues unabated, this review will also discuss the potential for developing therapies that target the alternative ATP-generating machinery of bacteria.
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Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Espécies Reativas de Nitrogênio/metabolismo , Animais , Antibacterianos/química , HumanosRESUMO
Preventing and eradicating biofilms remains a challenge in clinical and industrial settings. Recently, the present authors demonstrated that silver oxynitrate (Ag7NO11) prevented and eradicated single-species planktonic and biofilm populations of numerous microbes at lower concentrations than other silver (Ag) compounds. Here, the antimicrobial and anti-biofilm efficacy of Ag7NO11 is elaborated by testing its in vitro activity against combinations of dual-species, planktonic and biofilm populations of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. As further evidence emerges that multispecies bacterial communities are more common in the environment than their single-species counterparts, this study reinforces the diverse applicability of the minimal biofilm eradication concentration (MBEC™) assay for testing antimicrobial compounds against biofilms. Furthermore, this study demonstrated that Ag7NO11 had enhanced antimicrobial and anti-biofilm activity compared to copper sulfate (CuSO4) and silver nitrate (AgNO3) against the tested bacterial species.
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Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Nitratos/farmacologia , Plâncton/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Compostos de Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Plâncton/crescimento & desenvolvimento , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
The emergence of multidrug-resistant pathogens and the prevalence of biofilm-related infections have generated a demand for alternative anti-microbial therapies. Metals have not been explored in adequate detail for their capacity to combat infectious disease. Metal compounds can now be found in textiles, medical devices and disinfectants-yet, we know little about their efficacy against specific pathogens. To help fill this knowledge gap, we report on the anti-microbial and antibiofilm activity of seven metals: silver, copper, titanium, gallium, nickel, aluminum and zinc against three bacterial strains, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. To evaluate the capacity of metal ions to prevent the growth of, and eradicate biofilms and planktonic cells, bacterial cultures were inoculated in the Calgary Biofilm Device (minimal biofilm eradication concentration) in the presence of the metal salts. Copper, gallium and titanium were capable of preventing planktonic and biofilm growth, and eradicating established biofilms of all tested strains. Further, we observed that the efficacies of the other tested metal salts displayed variable efficacy against the tested strains. Further, contrary to the enhanced resistance anticipated from bacterial biofilms, particular metal salts were observed to be more effective against biofilm communities versus planktonic cells. In this study, we have demonstrated that the identity of the bacterial strain must be considered before treatment with a particular metal ion. Consequent to the use of metal ions as anti-microbial agents to fight multidrug-resistant and biofilm-related infections increases, we must aim for more selective deployment in a given infectious setting.
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Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Metais/farmacologia , Plâncton/efeitos dos fármacos , Antibacterianos/química , Biofilmes/crescimento & desenvolvimento , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Metais/química , Testes de Sensibilidade Microbiana , Plâncton/crescimento & desenvolvimento , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacosRESUMO
It appears that a great many chiropractors and chiropractic institutions are involved in health care initiatives in developing countries. Developing nations present extraordinary opportunities to do good, but also carry risks, for practitioners and organizations, which may not be obvious prior to actual local engagement. This paper describes the guiding principles under which one international collaboration has evolved in rural Tanzania, a so-called 'low resource' setting where the majority of families subsist in extreme poverty. Several challenges to effective care are also identified.
Il semble qu'un nombre important de chiropraticiens et d'institutions chiropratiques participent à des initiatives de soins médicaux dans des pays en développement. Ces pays offrent beaucoup d'occasions pour des actions positives, mais comportent aussi pour les praticiens et les organisations des risques qui ne sont pas toujours évidents avant l'engagement sur le terrain. Cet article décrit les principes directeurs sur lesquels a évolué une initiative collaborative internationale en Tanzanie rurale, un environnement décrit comme faible en ressources, où la majorité des familles subsiste dans une extrême pauvreté. L'article cerne en outre plusieurs défis à relever pour offrir des soins efficaces.
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Anthropogenic activities have resulted in the intensified use of water resources. For example, open pit bitumen extraction by Canada's oil sands operations uses an estimated volume of three barrels of water for every barrel of oil produced. The waste tailings-oil sands process water (OSPW)-are stored in holding ponds, and present an environmental concern as they are comprised of residual hydrocarbons and metals. Following the hypothesis that endogenous OSPW microbial communities have an enhanced tolerance to heavy metals, we tested the capacity of planktonic and biofilm populations from OSPW to withstand metal ion challenges, using Cupriavidus metallidurans, a known metal-resistant organism, for comparison. The toxicity of the metals toward biofilm and planktonic bacterial populations was determined by measuring the minimum biofilm inhibitory concentrations (MBICs) and planktonic minimum inhibitory concentrations (MICs) using the MBEC ™ assay. We observed that the OSPW community and C. metallidurans had similar tolerances to 22 different metals. While thiophillic elements (Te, Ag, Cd, Ni) were found to be most toxic, the OSPW consortia demonstrated higher tolerance to metals reported in tailings ponds (Al, Fe, Mo, Pb). Metal toxicity correlated with a number of physicochemical characteristics of the metals. Parameters reflecting metal-ligand affinities showed fewer and weaker correlations for the community compared to C. metallidurans, suggesting that the OSPW consortia may have developed tolerance mechanisms toward metals present in their environment.
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Cupriavidus , Metais Pesados/metabolismo , Consórcios Microbianos/fisiologia , Petróleo/microbiologia , Microbiologia da Água , Cupriavidus/isolamento & purificação , Cupriavidus/metabolismoRESUMO
Historically it has been accepted, and recent research has established, that silver (Ag) is an efficacious antimicrobial agent. A dwindling pipeline of new antibiotics, combined with an increase in the number of antibiotic-resistant infections, is bringing Ag to the fore as a therapeutic compound to treat infectious diseases. Currently, many formulations of Ag are being deployed for commercial and medical purposes, with various degrees of effectiveness at killing microbial cells. Here, we evaluated the antimicrobial and antibiofilm capacity of our lead compound, silver oxynitrate [Ag(Ag3O4)2NO3 or Ag7NO11], against other metal compounds with documented antimicrobial activity, including Ag2SO4, AgNO3, silver sulfadiazine (AgSD), AgO, Ag2O, and CuSO4. Our findings reveal that Ag7NO11 eradicates biofilm and planktonic populations of Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, uropathogenic Escherichia coli (UPEC), fluoroquinolone-resistant Pseudomonas aeruginosa (FQRP), and methicillin-resistant Staphylococcus aureus (MRSA) at lower concentrations than those of the other tested metal salts. Altogether, our results demonstrate that Ag7NO11 has an enhanced efficacy for the treatment of biofilm-forming pathogens.
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Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Fungos/efeitos dos fármacos , Compostos de Prata/farmacologia , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Metais/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nitratos/farmacologiaRESUMO
The caustic hot water extraction process used to release bitumen from the Alberta oil sands generates large volumes of tailings waste, or oil sands process water (OSPW). OSPW contains several components of environmental concern including diluents, polyaromatic hydrocarbons, heavy metals, and naphthenic acids (NAs); the latter are of particular concern as they are acutely toxic to aquatic organisms and mammals. Studies have demonstrated that the naturally occurring OSPW bacteria are capable of metabolizing the NAs. However, this in situ process takes place over hundreds of years, and is incomplete, leaving a recalcitrant fraction of NAs intact. In this study we explore options for recovering and harnessing the naturally occurring OSPW bacteria for potential future use in an aerobic ex situ OSPW treatment system. Here we evaluate our recovered microbes on their ability to degrade two model NAs, cyclohexane carboxylic acid and cyclohexane acetic acid. Using OSPW as a source for a bacterial inoculum, we were able to compare single and multispecies OSPW cultures, grown as either a biofilm, or as a planktonic suspension. Furthermore, we examined the effect of available nutrients on the ability of these cultures to degrade NAs. All biofilms were grown using the Calgary Biofilm Device. GC-MS, and GC-FID reveal that multispecies biofilm and planktonic cultures are each capable of degrading both NAs; a trait not observed for single species cultures. Moreover, complementary carbon sources have a tangible effect on the ability of the cultures to initiate the degradation of the NAs.