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A 66-year-old immunocompetent man with preceding travel through the Northeastern United States developed Guillain-Barré syndrome. A broad search for infections revealed intraerythrocytic parasites on blood smear and positive polymerase chain reaction for Babesia microti; elevated IgM/IgG serologies for Ehrlichia chaffeensis; elevated IgM/IgG serologies and qualitative polymerase chain reaction for Epstein-Barr virus; and fecal culture growth of Arcobacter butzleri. In this report, we discuss the known or suspected association of these infectious agents with Guillain-Barré syndrome. This case also highlights the importance, in the setting of endemic exposure, of screening for multiple coinfections that can be transmitted by the same arthropod vector.
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Streptococcus mutans is a Gram-positive bacterium highly associated with dental caries, and it has a strong biofilm-forming ability, especially in a sugar-rich environment. Many strategies have been undertaken to prevent dental caries by targeting these bacteria. Recently, we observed that a sustained-release varnish containing triclosan and cannabidiol (CBD) was more efficient than each compound alone in preventing biofilm formation by the fungus Candida albicans, which is frequently involved in oral infections together with S. mutans. It was therefore inquiring to study the effect of this drug combination on S. mutans. We observed that the combined treatment of triclosan and CBD had stronger anti-bacterial and anti-biofilm activity than each compound alone, thus enabling the use of lower concentrations of each drug to achieve the desired effect. The combined drug treatment led to an increase in the SYTO 9low, propidium iodide (PI)high bacterial population as analyzed by flow cytometry, indicative for bacteria with disrupted membrane. Both triclosan and CBD induced membrane hyperpolarization, although there was no additive effect on this parameter. HR-SEM images of CBD-treated bacteria show the appearance of elongated and swollen bacteria with several irregular septa structures, and upon combined treatment with triclosan, the bacteria took on a swollen ellipse and sometimes oval morphology. Increased biofilm formation was observed at sub-MIC concentrations of each compound alone, while combining the drugs at these sub-MIC concentrations, the biofilm formation was prevented. The inhibition of biofilm formation was confirmed by CV biomass staining, MTT metabolic activity, HR-SEM and live/dead together with exopolysaccharide (EPS) staining visualized by spinning disk confocal microscopy. Importantly, the concentrations required for the anti-bacterial and anti-biofilm activities toward S. mutans were non-toxic to the normal Vero epithelial cells. In conclusion, the data obtained in this study propose a beneficial role of combined triclosan/CBD treatment for potential protection against dental caries.
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Here, we present a case report of a healthy Asian woman with no past medical history presenting with severe acute liver injury associated with ingestion of kombucha. We also discuss the active ingredients in kombucha and the evidence behind its efficacy. This case emphasizes that although herbal teas have been proposed to have numerous health benefits, much is unknown about the amount that can be safely ingested.
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Dental caries is caused by biofilm-forming acidogenic bacteria, especially Streptococcus mutans, and is still one of the most prevalent human bacterial diseases. The potential use of cannabidiol (CBD) in anti-bacterial therapies has recently emerged. Here we have studied the anti-bacterial and anti-biofilm activity of CBD against S. mutans. We measured minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC). The bacterial growth and changes in pH values were measured in a kinetic study. The biofilm biomass was assessed by Crystal Violet staining and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) metabolic assay. Spinning Disk Confocal Microscopy (SDCM) was used to assess biofilm structure, bacterial viability and extracellular polysaccharide (EPS) production. CBD inhibited S. mutans planktonic growth and biofilm formation in a dose-dependent manner, with similar MIC and MBIC values (5 µg/mL). CBD prevented the bacteria-mediated reduction in pH values that correlated with bacterial growth inhibition. SDCM showed a decrease of 50-fold in live bacteria and EPS production. CBD significantly reduced the viability of preformed biofilms at 7.5 µg/mL with an 80 ± 3.1% reduction of metabolic activity. At concentrations above 20 µg/mL, there was almost no bacterial recovery in the CBD-treated preformed biofilms even 48 h after drug withdrawal. Notably, precoating of the culture plate surfaces with CBD prior to incubation with bacteria inhibited biofilm development. Additionally, CBD was found to induce membrane hyperpolarization in S. mutans. Thus, CBD affects multiple processes in S. mutans including its cariogenic properties. In conclusion, we show that CBD has a strong inhibitory effect against cariogenic bacteria, suggesting that it is a potential drug adjuvant for reducing oral pathogenic bacterial load as well as protecting against dental caries.
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Canabidiol , Cárie Dentária , Humanos , Streptococcus mutans , Canabidiol/farmacologia , Canabidiol/metabolismo , Ácidos Carboxílicos/metabolismo , Biofilmes , Antibacterianos/farmacologia , Antibacterianos/metabolismoRESUMO
Background: It has been confirmed that bacterial biofilm covering dental implants is the main microbial source causing preimplant infectious and inflammatory diseases. The purpose of this study was to evaluate the antibacterial/antibiofilm effect of chlorhexidine, incorporated into a sustained-release varnish of chlorhexidine (SRV-CHX) coating, on dental abutments. Materials and Methods: Three kinds of dental abutments were used: a high-performance semi-crystalline engineering thermoplastic polyetheretherketone (PEAK) healing abutment, a titanium healing abutment, and a titanium permanent abutment. These abutments were coated with SRV-CHX or SRV-placebo and exposed daily to fresh cultures of Streptococcus mutans. The effect of SRV-CHX on S. mutans growth on agar plates was studied by measuring the zone of inhibition (ZOI) around each tested abutment every day for a period of 36 days. Biofilm formation on the SRV-CHX/placebo-coated abutments was detected using confocal laser scanning microscopy (CLSM) and high-resolution scanning electron microscopy (HR-SEM), energy dispersive X-ray analysis (EDX), and monitored by crystal violet (CV) staining. Results: SRV-CHX-coated abutments 2 and 3 were able to inhibit S. mutans growth for 34 days, while abutment 1 inhibited growth for 32 days. Abutment-associated biofilm formation was notably inhibited by SRV-CHX coating after 13 days of incubation with S. mutans. Finally, the biofilm formed around SRV-CHX-coated abutments was completely inhibited up to 12 days of abutment exposure to S. mutans. Conclusion: Coating of dental abutments with SRV-CHX demonstrated long-term effective inhibition of S. mutans growth and biofilm formation on the abutment surface.
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Candida albicans is a common fungal pathogen. Biofilm formation on various surfaces is an important determinant of C. albicans pathogenicity. Our previous results demonstrated the high potential of cannabidiol (CBD) to affect C. albicans biofilms. Based on these data, we investigated the possibility of incorporating CBD and/or triclosan (an antimicrobial agent that is widely utilized in dentistry) in a sustained-release varnish (SRV) (SRV-CBD, SRV-triclosan) to increase their pharmaceutical potential against C. albicans biofilm, as well as that of the mixture of the agents into SRV (SRV-CBD/triclosan). The study was conducted in a plastic model, on agar, and in an ex vivo tooth model. Our results demonstrated strong antibiofilm activity of SRV-CBD and SRV-triclosan against C. albicans in all tested models. Both formulations were able to inhibit biofilm formation and to remove mature fungal biofilm. In addition, SRV-CBD and SRV-triclosan altered C. albicans morphology. Finally, we observed a dramatic enhancement of antibiofilm activity when combined SRV-CBD/triclosan was applied. In conclusion, we propose that incorporation of CBD or triclosan into SRV is an effective strategy to fight fungal biofilms. Importantly, the data demonstrate that our CBD/triclosan varnish is safe, and is not cytotoxic for normal mammalian cells. Furthermore, we propose that CBD and triclosan being in mixture in SRV exhibit complementary antibiofilm activity, and thus can be explored for further development as a potential treatment against fungal infections.
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Background: Guidelines for acute upper gastrointestinal bleeding (UGIB) recommend use of proton pump inhibitors (PPI) administered by continuous IV infusion (CI). Although data suggest comparable outcomes with CI and IV push (IVP) dosing post-endoscopy, there are limited data to support IVP PPI as the pre-endoscopy regimen. Objective: To evaluate the impact of a pharmacist-managed protocol for reducing PPI CIs and substitution of PPI IVP dosing in hemodynamically stable patients with suspected acute upper gastrointestinal bleeding (UGIB) prior to endoscopic intervention. Design, Setting, and Participants: Retrospective study; Tertiary-care community teaching hospital; Hemodynamically stable adults with confirmed or suspected UGIB. Hemodynamic stability was defined as a systolic blood pressure >90 mmHg, heart rate <100 beats, mean arterial pressure >65 mmHg, and no requirement for vasopressors. Intervention: All iterations of treatment recommendations encouraged an initial pantoprazole 80 mg IVP dose. In the pre-intervention group, patients were then treated at the at the provider's discretion with the majority receiving CI pantoprazole. After implementation of the original protocol (Phase I), all hemodynamically stable patients were allowed 1 bag of CI pantoprazole (80 mg infused over 10 hours) before being transitioned by the pharmacist to pantoprazole 40 mg IVP every 12 hours. After internal analysis, the protocol was revised to allow patients to be immediately transitioned to IVP dosing without an initial CI (Phase II). Main Outcome: Incidence of continued bleeding or re-bleeding within 7 days of initial PPI dose. Results: A total of 325 patients were included across all 3 study phases. The median number of CI bags per patient was reduced from 4 pre-intervention, to 1.5 in phase I, and to 0 in phase II (P < .001). The primary endpoint of continued bleeding or re-bleeding within 7 days was similar across all 3 groups (5.0% vs 6.5% vs 5.2%, P = .92). Mean intravenous pantoprazole costs were reduced by $21.73/patient. Conclusions: Movement toward preferential use of IVP PPI prior to endoscopy for hemodynamically stable patients with confirmed or suspected UGIBs resulted in similar rates of continued bleeding or re-bleeding and generated modest cost savings. These findings warrant further investigation.
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Objectives: Simulation is a commonly used modality to teach paediatric procedural skills, however, it is resource intensive. Which paediatric skills are best taught using simulation is not known. This study aims to examine what skills to simulate, allowing for the best use of resources in ever expanding curricula. Method: We administered a questionnaire to community and hospitalist general paediatricians in Canada asking them to rate the importance of maintaining competency in each paediatric procedural skill and the frequency with which they perform the skill in their practice. Results: Skills that were rated as highly important and also high frequency were: bag-mask ventilation (BMV), lumbar puncture, neonatal cardiopulmonary resuscitation (CPR), specimen procurement for infectious diseases, immunization, and ear curettage. Skills that were rated as highly important but low frequency were: paediatric CPR, intraosseous needle insertion, neonatal intubation, defibrillation, gathering specimens for evidence of child maltreatment, paediatric intubation, cervical spine immobilization, and oral/nasogastric tube placement. Conclusion: Paediatric procedural skills are rated variably in terms of importance and frequency of use in general paediatric practice. Eight skills of high importance are infrequently performed and should be targeted for teaching via simulation.
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Objective: The objective of this study was to identify nephrology topics of lowest perceived competency and importance for general paediatricians. Methods: Surveys were distributed to general paediatricians, paediatric residents, paediatric residency program directors, and paediatric nephrologists. Perceived importance and competence were rated on a 5-point Likert scale. Means and 95% confidence intervals were calculated. Results: Mean perceived competency from general paediatricians across all nephrology domains was 3.0, 95%CI (2.9 to 3.1) and mean importance was 3.2, 95%CI (3.1 to 3.3). Domains scoring below the means for competence and importance, respectively were kidney stones (2.5, 95%CI [2.2 to 2.7]) and 2.6, 95%CI [2.3 to 2.8]), acute kidney injury (2.5, 95%CI [2.2 to 2.8] and 2.4, 95%CI [2.1 to 2.8]), chronic kidney disease (1.9, 95%CI [1.7 to 2.2] and 2.1, 95%CI [1.8 to 2.4]), tubular disorders (1.8, 95%CI [1.6 to 2.0] and 2.0, 95%CI [1.8 to 2.3]), and kidney transplant (1.6, 95%CI [1.4 to 1.8] and 1.7, 95%CI [1.4 to 1.9]). Residents, program directors, and paediatric nephrologists agreed that stones, chronic kidney disease, tubular disorders, and transplant were of lower importance. However, acute kidney injury was the domain with the largest discrepancy in perceived importance between residents (4.4, 95%CI [4.2 to 4.6]), nephrologists (4.2, 95%CI [3.8 to 4.6]), and program directors (4.2, 95%CI [3.7 to 4.7]) compared to general paediatricians ([2.4, 95%CI [2.1 to 2.8]; P<0.05). Conclusion: Paediatricians did not believe acute kidney injury was important to their practice, despite expert opinion and evidence of long-term consequences. Educational interventions must address deficits in crucial domains of renal health in paediatrics.
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A middle age man with a history of diabetes mellitus type 2, hypertension, migraine and eosinophilic granulomatosis with polyangiitis (EGPA) with polyneuropathy in remission presented with paresthesia and motor weakness soon after receiving the Pfizer-BioNTech COVID-19 messanger RNA (mRNA) vaccine. The patient had polyneuropathy 10 years ago secondary to EGPA, which had resolved. EGPA was diagnosed on the basis of typical symptoms and positive sural nerve biopsy. Five days after receiving the first dose of COVID-19 vaccine, he developed heaviness and reduced dexterity of both the upper extremities, which progressed to patchy and asymmetric motor weakness of all four extremities. Given the lack of clear alternative explanation after a thorough work up, recrudescence of underlying asymptomatic polyneuropathy due to a possible reaction to COVID-19 mRNA vaccine was considered although a temporal association with vaccine dose does not prove causality. He was treated with corticosteroids with slow improvement of his symptoms.
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COVID-19 , Síndrome de Churg-Strauss , Granulomatose com Poliangiite , Polineuropatias , Vacina BNT162 , Vacinas contra COVID-19/efeitos adversos , Síndrome de Churg-Strauss/complicações , Granulomatose com Poliangiite/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/complicações , Polineuropatias/tratamento farmacológico , Polineuropatias/etiologia , Vacinas Sintéticas , Vacinas de mRNARESUMO
We offer an explanation how immune complexes are deposited in tissues of auto-immune disorders in humans. These disorders are characterized by the accumulation in tissues of large numbers of neutrophils, which can shed out long extracellular traps (NETs) rich in a nucleosome and in highly opsonic poly cations, histone, LL37, defensins and elastase possessing properties similar to antibodies. These can bind by strong electrostatic forces to negatively charged domains in immune globulins, thus facilitating their deposition and internalization by tissue cells. However, the main cause for tissue damage in auto-immune patients is inflicted by the plethora of toxic pro-inflammatory agents released by activated neutrophils. To ameliorate tissue damage and the cytokine storms, it is recommended to administer to patients highly anionic heparins accompanied by steroids, methotrexate, colchicine, copaxone, and also by additional agents which retarded neutrophil functions.
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Complexo Antígeno-Anticorpo , Armadilhas Extracelulares , Complexo Antígeno-Anticorpo/metabolismo , Armadilhas Extracelulares/metabolismo , Histonas/metabolismo , Humanos , Neutrófilos/metabolismoRESUMO
OBJECTIVES: In this study, we aimed to develop a novel, sustained release varnish (SRV) for voice prostheses (VP) releasing chlorhexidine (CHX), for the prevention of biofilm formation caused by the common oral bacteria Streptococcus mutans on VP surfaces. METHODS: This study was performed in an in vitro model as a step towards future in vivo trials. VPs were coated with a SRV containing CHX (SRV-CHX) or SRV alone (placebo-SRV) that were daily exposed to S. mutans. The polymeric materials of SRV were composed of ethylcellulose and PEG-400. Biofilm formation was assessed by DNA quantification (qPCR), crystal violet staining, confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and kinetics experiments. RESULTS: The amount of DNA in the biofilms formed by S. mutans on VP surfaces coated once with SRV-CHX (1.024 ± 0.218 ng DNA/piece) was 58.5 ± 8.8% lower than that of placebo-SRV-coated VPs (2.465 ± 0.198 ng DNA/piece) after a 48-h exposure to S. mutans (p = 0.038). Reduced biofilm mass on SRV-CHX-coated VPs was visually confirmed by CLSM and SEM. CV staining of SRV-CHX single-coated VPs that have been exposed to S. mutans nine times showed a 98.1 ± 0.2% reduction in biofilm mass compared to placebo-SRV-coated VPs (p = 0.003). Kinetic experiments revealed that SRV-CHX triple-coated VPs could delay bacterial growth for 23 days. CONCLUSIONS: Coating VPs with SRV-CHX has an inhibitory effect on biofilm formation and prevents bacterial growth in their vicinities. This study is a proof-of-principle that paves the way for developing new clinical means for reducing both VPs' bacterial biofilm formation and device failure.
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Laringe Artificial , Streptococcus mutans , Biofilmes , Clorexidina/farmacologia , Preparações de Ação RetardadaRESUMO
Metastasis to the gastrointestinal tract is rare. We performed a retrospective analysis to identify patients with metastatic disease to the gastrointestinal tract using two databases containing pathology results from all endoscopic procedures conducted by nearly 200 gastroenterologists in a community setting over a 14-year period. Forty-nine patients were diagnosed with metastasis to the gastrointestinal tract by endoscopy during the study period. Most were women (71%). The most common metastases to the gastrointestinal tract identified by endoscopy were breast cancers (n = 18), followed by melanomas (n = 12), ovarian cancers (n = 7), kidney cancers (n = 5), prostate cancers (n = 2), lung cancer (n = 1), and pancreatic cancer (n = 1). Three patients had unknown primary sites. Among women, the three leading known primary tumor sites were breast, ovary, and melanoma. Among men, the three leading primary tumor sites were melanoma, kidney, and prostate. The stomach was the most common portion of the gastrointestinal tract involved by metastases. Most affected women and were most frequently encountered in the stomach.
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The autoimmune disorder rheumatoid arthritis (RA) is a relapsing and chronic inflammatory disease that affects the synovial cells, cartilage, bone, and muscle. It is characterised by the accumulation of huge numbers of polymorphonuclear neutrophils (PMNs) and macrophages in the synovia. Auto-antibodies are deposited in the joint via the activity of highly cationic histones released from neutrophil extracellular traps (NETs) in a phenomenon termed NETosis. The cationic histones function as opsonic agents that bind to negatively charged domains in autoantibodies and complement compounds via strong electrostatic forces, facilitating their deposition and endocytosis by synovial cells. However, eventually the main cause of tissue damage is the plethora of toxic pro-inflammatory substances released by activated neutrophils recruited by cytokines. Tissue damage in RA can also be accompanied by infections which, upon bacteriolysis, release cell-wall components that are toxic to tissues. Some amelioration of the damaged cells and tissues in RA may be achieved by the use of highly anionic heparins, which can neutralize cationic histone activity, provided that these polyanions are co-administrated with anti-inflammatory drugs such as steroids, colchicine, or methotrexate, low molecular weight antioxidants, proteinase inhibitors, and phospholipase A2 inhibitors.
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OBJECTIVE: We report a case of pituitary apoplexy (PA) with negative radiographic findings for PA and cerebrospinal fluid (CSF) analysis consistent with neutrophilic meningitis. PA is a rare endocrinopathy requiring prompt diagnosis and treatment. Presentation with acute neutrophilic meningitis is uncommon. METHODS: The diagnostic modalities included pituitary function tests (adrenocorticotropic hormone, thyroid-stimulating hormone, luteinizing hormone, prolactin), brain computed tomography and magnetic resonance imaging (MRI), and CSF analysis. RESULTS: A 67-year-old man presented with worsening headache, nausea, and retching. He was somnolent with an overall normal neurologic examination other than a peripheral vision defect in the left eye. MRI showed a pituitary mass bulging into the suprasellar cistern with optic chiasm elevation, consistent with pituitary macroadenoma. Laboratory evaluation revealed decreased levels of adrenocorticotropic hormone, random cortisol, thyroid-stimulating hormone, thyroxine, luteinizing hormone, and testosterone. He had worsening encephalopathy with left eye ptosis and decreased vision, prompting a repeat computed tomography and MRI, showing no interval change in the pituitary adenoma or evidence of bleeding. CSF analysis revealed a leukocyte count of 1106/mm3 (89% neutrophils), a total protein level of 138 mg/dL, red blood cell count of 2040/mm3 without xanthochromia, and glucose level of 130 mg/dL. The CSF culture result was negative. Transsphenoidal resection revealed a necrotic pituitary adenoma with apoplexy. CONCLUSIONS: Including PA in the differential diagnosis of acute headache is important, particularly in patients with visual disturbances. PA can present with sterile meningitis, mimicking acute bacterial meningitis. While neuroimaging can help detect PA, the diagnosis of PA remains largely clinical.
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BACKGROUND: The COVID-19 pandemic has a worldwide impact on all health services, including childhood immunizations. In Canada, there is limited data to quantify and characterize this issue. METHODS: We conducted a descriptive, cross-sectional study by distributing online surveys to physicians across Ontario. The survey included three sections: provider characteristics, impact of COVID-19 on professional practice, and impact of COVID-19 on routine childhood immunization services. Multivariable logistic regression identified factors associated with modification of immunization services. RESULTS: A total of 475 respondents answered the survey from May 27th to July 3rd 2020, including 189 family physicians and 286 pediatricians. The median proportion of in-person visits reported by physicians before the pandemic was 99% and dropped to 18% during the first wave of the pandemic in Ontario. In total, 175 (44.6%) of the 392 respondents who usually provide vaccination to children acknowledged a negative impact caused by the pandemic on their immunization services, ranging from temporary closure of their practice (n = 18; 4.6%) to postponement of vaccines in certain age groups (n = 103; 26.3%). Pediatricians were more likely to experience a negative impact on their immunization services compared to family physicians (adjusted odds ratio [aOR] = 2.64, 95% CI: 1.48-4.68), as well as early career physicians compared to their more senior colleagues (aOR = 2.69, 95% CI: 1.30-5.56), whereas physicians from suburban settings were less impacted than physicians from urban settings (aOR = 0.62, 95% CI: 0.39-0.99). Some of the proposed solutions to decreased immunization services included assistance in accessing personal protective equipment, dedicated centers or practices for vaccination, universal centralized electronic immunization records and education campaigns for parents. CONCLUSIONS: COVID-19 has caused substantial modifications to pediatric immunization services across Ontario. Strategies to mitigate barriers to immunizations during the pandemic need to be implemented in order to avoid immunity gaps that could lead to an eventual increase in vaccine preventable diseases.
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COVID-19 , Pandemias , Criança , Estudos Transversais , Humanos , Imunização , Ontário/epidemiologia , SARS-CoV-2 , VacinaçãoRESUMO
Streptococcus halichoeri is a relatively newly identified species of pyogenic streptococci that causes zoonotic infection in humans. S. halichoeri was first described in 2004 as indigenous to seals, and only 8 reports of human S. halichoeri infection have been published. S. halichoeri grows as small, white, nonhemolytic colonies and may be strongly catalase-positive on routine blood agar media, which can lead to isolates being misidentified as coagulase-negative staphylococci. S. halichoeri tests positive for Lancefield group B antigen, like S. agalactiae, but can be identified with matrix-assisted laser desorption/ionization time of flight mass spectrometry or partial 16S rRNA sequencing. We describe 3 cases of S. halichoeri bone and joint infections in patients in the United States with underlying health conditions. In addition, we examine the microbiologic characteristics of S. halichoeri and discuss the importance of fully identifying this organism that might otherwise be disregarded as a skin commensal.
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Laboratórios , Infecções Estreptocócicas , Humanos , RNA Ribossômico 16S , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Streptococcus/genéticaRESUMO
Antibiotic resistance is a serious public health problem throughout the world. Overcoming methicillin and multidrug-resistant Staphylococcus aureus (MRSA/MDRSA) infections has become a challenge and there is an urgent need for new therapeutic approaches. We have previously demonstrated that the endocannabinoid Anandamide (AEA) can sensitize MRSA to antibiotics. Here we have studied the mechanism of action using a MDRSA clinical isolate that are sensitized by AEA to methicillin and norfloxacin. We found that AEA treatment halts the growth of both antibiotic-sensitive and antibiotic-resistant S. aureus. The AEA-treated bacteria become elongated and the membranes become ruffled with many protrusions. AEA treatment also leads to an increase in the percentage of bacteria having a complete septum, suggesting that the cell division is halted at this stage. The latter is supported by cell cycle analysis that shows an accumulation of bacteria in the G2/M phase after AEA treatment. We further observed that AEA causes a dose-dependent membrane depolarization that is partly relieved upon time. Nile red staining of the bacterial membranes indicates that AEA alters the membrane structures. Importantly, 4'-6-diamidino-2-phenylindole (DAPI) accumulation assay and ethidium bromide efflux (EtBr) assay unveiled that AEA leads to a dose-dependent drug accumulation by inhibiting drug efflux. In conclusion, our study demonstrates that AEA interferes with cell division, alters the membrane properties of MDRSA, and leads to increased intracellular drug retention, which can contribute to the sensitization of MDRSA to antibiotics.
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Antibacterianos/uso terapêutico , Ácidos Araquidônicos/farmacologia , Membrana Celular/efeitos dos fármacos , Endocanabinoides/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacocinética , Ácidos Araquidônicos/farmacocinética , Farmacorresistência Bacteriana Múltipla , Endocanabinoides/farmacocinética , Alcamidas Poli-Insaturadas/farmacocinéticaRESUMO
Candida albicans is a common fungal pathogen in humans. Biofilm formation is an important virulence factor of C. albicans infections. We investigated the ability of the plant-derived cannabidiol (CBD) to inhibit the formation and removal of fungal biofilms. Further, we evaluated its mode of action. Our findings demonstrate that CBD exerts pronounced time-dependent inhibitory effects on biofilm formation as well as disruption of mature biofilm at a concentration range below minimal inhibitory and fungicidal concentrations. CBD acts at several levels. It modifies the architecture of fungal biofilm by reducing its thickness and exopolysaccharide (EPS) production accompanied by downregulation of genes involved in EPS synthesis. It alters the fungal morphology that correlated with upregulation of yeast-associated genes and downregulation of hyphae-specific genes. Importantly, it represses the expression of C. albicans virulence-associated genes. In addition, CBD increases ROS production, reduces the intracellular ATP levels, induces mitochondrial membrane hyperpolarization, modifies the cell wall, and increases the plasma membrane permeability. In conclusion, we propose that CBD exerts its activity towards C. albicans biofilm through a multi-target mode of action, which differs from common antimycotic agents, and thus can be explored for further development as an alternative treatment against fungal infections.