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BACKGROUND: Osteopathic manipulative treatment (OMT), also known as osteopathic manipulative medicine (OMM), is a set of manual techniques, developed by Dr. Andrew Taylor Still, founder of osteopathic medicine, initially limited to osteopathic medicine, for the treatment of painful conditions. This toolset is now used by allopathic physicians, international osteopaths, physical therapists, chiropractors, and other healthcare workers for the treatment of musculoskeletal pain. OMT can be used in the emergency department (ED) for the treatment of musculoskeletal complaints as an adjunct to pharmacologic agents (e.g., NSAIDs), or an alternative to opioids. OBJECTIVE: This narrative review provides emergency clinicians with an understanding of OMT, including a broad overview of the basis, development, and common subtypes of OMT; data on OMT efficacy and on the use of conditions commonly encountered in the ED setting; and information on how to implement the use of OMT in emergency medicine and urgent care settings. DISCUSSION: OMT can be used for a wide variety of acute and chronic pain conditions, particularly back pain, headaches, neck pain, and extremity pain (assuming that life-threatening conditions have been excluded). There are small studies and case series demonstrating both efficacy and subjective improvement with OMT, including in the ED. However, limitations to the current body of literature include: small numbers of patients, challenges with blinding and standardization, limited adverse event reporting, and most research has been outside of the ED setting. There is great opportunity for future studies and application of OMT in the ED. There are an increasing number of emergency clinicians incorporating OMT in their practice and despite the perception of OMT requiring extended periods of time to perform, current data suggests OMT does not prolong ED visits or cost to patients. OMT is a procedure with billing codes, and courses and training in OMT are available for both osteopathic and allopathic physicians. CONCLUSION: OMT is being used and has great potential in the management of acute and chronic musculoskeletal pain in the ED in addition to, or instead of pharmacologic agents, in particular as an opioid-sparing option.
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Colonization resistance (CR), the ability to block infections by potentially harmful microbes, is a fundamental function of host-associated microbial communities and highly conserved between animals and humans. Environmental factors such as antibiotics and diet can disturb microbial community composition and thereby predispose to opportunistic infections. The most prominent is Clostridioides difficile, the causative agent of diarrhea and pseudomembranous colitis. In addition, the risk to succumb to infections with genuine human enteric pathogens like nontyphoidal Salmonella (NTS) is also increased by a low-diverse, diet or antibiotic-disrupted microbiota. Despite extensive microbial community profiling efforts, only a limited set of microorganisms have been causally linked with protection against enteric pathogens. Furthermore, it remains a challenge to predict colonization resistance from complex microbiome signatures due to context-dependent action of microorganisms. In the past decade, the study of NTS infection has led to the description of several fundamental principles of microbiota-host-pathogen interaction. In this review, I will give an overview on the current state of knowledge in this field and outline experimental approaches to gain functional insight to the role of specific microbes, functions and metabolites in Salmonella-microbiota-host interaction. In particular, I will highlight the value of mouse infection models, which, in combination with culture collections, synthetic communities and gnotobiotic models have become essential tools to screen for protective members of the microbiota and establishing causal relationship and mechanisms in infection research.
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Enterocolite Pseudomembranosa , Microbiota , Infecções por Salmonella , Animais , Vida Livre de Germes , Camundongos , SalmonellaRESUMO
The yeast Saccharomyces cerevisiae genome is endowed with two distinct isoforms of Voltage-Dependent Anion Channel (VDAC). The isoform yVDAC2 is currently understudied with respect to the best known yVDAC1. Yet, since the discovery, the function of yVDAC2 was unclear, leading to the hypothesis that it might be devoid of a channel function. In this work we have elucidated, by bioinformatics modeling and electrophysiological analysis, the functional activity of yVDAC2. The conformation of yVDAC2 and, for comparison, of yVDAC1 were modeled using a multiple template approach involving mouse, human and zebrafish structures and both showed to arrange the sequences as the typical 19-stranded VDAC ß-barrel. Molecular dynamics simulations showed that yVDAC2, in comparison with yVDAC1, has a different number of permeation paths of potassium and chloride ions. yVDAC2 protein was over-expressed in the S. cerevisiae cells depleted of functional yVDAC1 (Δpor1 mutant) and, after purification, it was reconstituted in artificial membranes (planar lipid bilayer (PLB) system). The protein displayed channel-forming activity and the calculated conductance, voltage-dependence and ion selectivity values were similar to those of yVDAC1 and other members of VDAC family. This is the first time that yVDAC2 channel features are detected and characterized.
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Mitocôndrias/química , Membranas Mitocondriais/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Canal de Ânion 1 Dependente de Voltagem/química , Canal de Ânion 2 Dependente de Voltagem/química , Animais , Sítios de Ligação , Cloretos/química , Cloretos/metabolismo , Biologia Computacional , Expressão Gênica , Humanos , Transporte de Íons , Cinética , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Camundongos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Simulação de Dinâmica Molecular , Potássio/química , Potássio/metabolismo , Ligação Proteica , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Homologia Estrutural de Proteína , Canal de Ânion 1 Dependente de Voltagem/genética , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Canal de Ânion 2 Dependente de Voltagem/genética , Canal de Ânion 2 Dependente de Voltagem/metabolismo , Peixe-ZebraRESUMO
Fish otoliths are calcium carbonate biominerals that are involved in hearing and balance sensing. An organic matrix plays a crucial role in their formation. Otolith matrix macromolecule-64 (OMM-64) is a highly acidic, calcium-binding protein (CBP) found in rainbow trout otoliths. It is a component of high-molecular-weight aggregates, which influence the size, shape and polymorph of calcium carbonate in vitro. In this study, a protocol for the efficient expression and purification of OMM-64 was developed. For the first time, the complete structural characteristics of OMM-64 were described. Various biophysical methods were combined to show that OMM-64 occurs as an intrinsically disordered monomer. Under denaturing conditions (pH, temperature) OMM-64 exhibits folding propensity. It was determined that OMM-64 binds approximately 61 calcium ions with millimolar affinity. The folding-unfolding experiments showed that calcium ions induced the collapse of OMM-64. The effect of other counter ions present in trout endolymph on OMM-64 conformational changes was studied. The significance of disordered properties of OMM-64 and the possible function of this protein is discussed.
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Proteínas de Ligação ao Cálcio/química , Cálcio/química , Proteínas da Matriz Extracelular/química , Proteínas de Peixes/química , Proteínas Intrinsicamente Desordenadas/química , Membrana dos Otólitos/química , Animais , Sítios de Ligação , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Expressão Gênica , Concentração de Íons de Hidrogênio , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Oncorhynchus mykiss/fisiologia , Membrana dos Otólitos/metabolismo , Ligação Proteica , Dobramento de Proteína , Domínios e Motivos de Interação entre Proteínas , Desdobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , TemperaturaRESUMO
Foxp3 is considered to be the master regulator for the development and function of regulatory T cells (Treg). Recently Foxp3, has been detected in extra lymphoid tissue, and in hepatocytes and has been associated with hepatocellular carcinoma (HCC), although its role has not been defined. Since it is expected that there is a relationship between protein localization, activity and cellular function, the aim of this study was to explore the subcellular localization of Foxp3 in resting and stimulated human hepatocytes. Foxp3 expression was measured by flow cytometry, subcellular fractioning, and immunofluorescence, and this data was used to track the shuttling of Foxp3 in different subcellular compartments in hepatocytes (HepG2 cell line), stimulated by using the PKC activators (PMA), core and preS1/2 antigen from hepatitis B virus (HBV). Our data shows that besides the nuclear location, mitochondrial translocation was detected after stimulation with PMA and at to a lesser extent, with preS1/2. In addition, Foxp3 is localizes at outer mitochondrial membrane. These results suggest a non-canonical role of Foxp3 in the mitochondrial compartment in human hepatocytes, and opens a new field about their role in liver damages during HBV infection.
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Fatores de Transcrição Forkhead/metabolismo , Hepatócitos/metabolismo , Mitocôndrias/metabolismo , Antígenos Virais/metabolismo , Compartimento Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Citometria de Fluxo , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Mitocôndrias/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Transporte Proteico/efeitos dos fármacos , Frações Subcelulares/metabolismo , Acetato de Tetradecanoilforbol/farmacologiaRESUMO
Methylobacillus sp. zju323 was adopted to improve the biosynthesis of pyrroloquinoline quinone (PQQ) by systematic optimization of the fermentation medium. The Plackett-Burman design was implemented to screen for the key medium components for the PQQ production. CoCl2 · 6H2O, ρ-amino benzoic acid, and MgSO4 · 7H2O were found capable of enhancing the PQQ production most significantly. A five-level three-factor central composite design was used to investigate the direct and interactive effects of these variables. Both response surface methodology (RSM) and artificial neural network-genetic algorithm (ANN-GA) were used to predict the PQQ production and to optimize the medium composition. The results showed that the medium optimized by ANN-GA was better than that by RSM in maximizing PQQ production and the experimental PQQ concentration in the ANN-GA-optimized medium was improved by 44.3% compared with that in the unoptimized medium. Further study showed that this ANN-GA-optimized medium was also effective in improving PQQ production by fed-batch mode, reaching the highest PQQ accumulation of 232.0 mg/L, which was about 47.6% increase relative to that in the original medium. The present work provided an optimized medium and developed a fed-batch strategy which might be potentially applicable in industrial PQQ production.
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Microbiologia Industrial/métodos , Methylobacillus/metabolismo , Cofator PQQ/metabolismo , Algoritmos , Meios de Cultura/metabolismo , Fermentação , Redes Neurais de ComputaçãoRESUMO
Recent studies show that a single bout of meditation can impact information processing. We were interested to see whether this impact extends to attentional focusing and the top-down control over irrelevant information. Healthy adults underwent brief single bouts of either focused attention meditation (FAM), which is assumed to increase top-down control, or open monitoring meditation (OMM), which is assumed to weaken top-down control, before performing a global-local task. While the size of the global-precedence effect (reflecting attentional focusing) was unaffected by type of meditation, the congruency effect (indicating the failure to suppress task-irrelevant information) was considerably larger after OMM than after FAM. Our findings suggest that engaging in particular kinds of meditation creates particular cognitive-control states that bias the individual processing style toward either goal-persistence or cognitive flexibility.
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Atenção/fisiologia , Cognição/fisiologia , Meditação/psicologia , Análise e Desempenho de Tarefas , Adolescente , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The AAA-ATPase Cdc48 (also called p97 or VCP) acts as a key regulator in proteolytic pathways, coordinating recruitment and targeting of substrate proteins to the 26S proteasome or lysosomal degradation. However, in contrast to the well-known function in ubiquitin-dependent cellular processes, the physiological relevance of Cdc48 in organismic development and maintenance of protein homeostasis is less understood. Therefore, studies on multicellular model organisms help to decipher how Cdc48-dependent proteolysis is regulated in time and space to meet developmental requirements. Given the importance of developmental regulation and tissue maintenance, defects in Cdc48 activity have been linked to several human pathologies including protein aggregation diseases. Thus, addressing the underlying disease mechanisms not only contributes to our understanding on the organism-wide function of Cdc48 but also facilitates the design of specific medical therapies. In this review, we will portray the role of Cdc48 in the context of multicellular organisms, pointing out its importance for developmental processes, tissue surveillance, and disease prevention. This article is part of a Special Issue entitled: Ubiquitin-Proteasome System. Guest Editors: Thomas Sommer and Dieter H. Wolf.
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Adenosina Trifosfatases/fisiologia , Envelhecimento/genética , Proteínas de Ciclo Celular/fisiologia , Crescimento e Desenvolvimento/genética , Animais , Proliferação de Células , Humanos , Estabilidade Proteica , Deficiências na Proteostase/genética , Reprodução/fisiologia , Proteína com ValosinaRESUMO
Meditation is becoming an increasingly popular topic for scientific research and various effects of extensive meditation practice (ranging from weeks to several years) on cognitive processes have been demonstrated. Here we show that extensive practice may not be necessary to achieve those effects. Healthy adult non-meditators underwent a brief single session of either focused attention meditation (FAM), which is assumed to increase top-down control, or open monitoring meditation (OMM), which is assumed to weaken top-down control, before performing an Attentional Blink (AB) task - which assesses the efficiency of allocating attention over time. The size of the AB was considerably smaller after OMM than after FAM, which suggests that engaging in meditation immediately creates a cognitive-control state that has a specific impact on how people allocate their attention over time.
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Atenção/fisiologia , Intermitência na Atenção Visual/fisiologia , Função Executiva/fisiologia , Meditação , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Here we consider the possibility that meditation has an immediate impact on information processing. Moreover, we were interested to see whether this impact affects attentional input control, as previous observations suggest, or the handling of response conflict. Healthy adults underwent a brief single session of either focused attention meditation (FAM), which is assumed to increase top-down control, or open monitoring meditation (OMM), which is assumed to weaken top-down control, before performing a Simon task-which assesses conflict-resolution efficiency. While the size of the Simon effect (reflecting the efficiency of handling response conflict) was unaffected by type of meditation, the amount of dynamic behavioral adjustments (i.e., trial-to-trial variability of the Simon effect: the Gratton effect) was considerably smaller after OMM than after FAM. Our findings suggest that engaging in meditation instantly creates a cognitive-control state that has a specific impact on conflict-driven control adaptations.
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Atenção , Cognição , Meditação , Análise e Desempenho de Tarefas , Adaptação Psicológica , Adolescente , Feminino , Humanos , Masculino , Tempo de Reação , Adulto JovemRESUMO
Alzheimer's disease and Parkinson's disease are neurodegenerative disorders characterised by the misfolding of proteins into soluble prefibrillar aggregates. These aggregate complexes disrupt mitochondrial function, initiating a pathophysiological cascade leading to synaptic and neuronal degeneration. In order to explore the interaction of amyloid aggregates with mitochondrial membranes, we made use of two in vitro model systems, namely: (i) lipid vesicles with defined membrane compositions that mimic those of mitochondrial membranes, and (ii) respiring mitochondria isolated from neuronal SH-SY5Y cells. External application of soluble prefibrillar forms, but not monomers, of amyloid-beta (Aß42 peptide), wild-type α-synuclein (α-syn), mutant α-syn (A30P and A53T) and tau-441 proteins induced a robust permeabilisation of mitochondrial-like vesicles, and triggered cytochrome c release (CCR) from isolated mitochondrial organelles. Importantly, the effect on mitochondria was shown to be dependent upon cardiolipin, an anionic phospholipid unique to mitochondria and a well-known key player in mitochondrial apoptosis. Pharmacological modulators of mitochondrial ion channels failed to inhibit CCR. Thus, we propose a generic mechanism of thrilling mitochondria in which soluble amyloid aggregates have the intrinsic capacity to permeabilise mitochondrial membranes, without the need of any other protein. Finally, six small-molecule compounds and black tea extract were tested for their ability to inhibit permeation of mitochondrial membranes by Aß42, α-syn and tau aggregate complexes. We found that black tea extract and rosmarinic acid were the most potent mito-protectants, and may thus represent important drug leads to alleviate mitochondrial dysfunction in neurodegenerative diseases.
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Peptídeos beta-Amiloides/metabolismo , Membranas Mitocondriais/metabolismo , Polifenóis/farmacologia , Linhagem Celular Tumoral , Humanos , Membranas Mitocondriais/efeitos dos fármacos , Permeabilidade , Proteínas Recombinantes/metabolismo , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismoRESUMO
Anoikis is a programmed cell death induced upon cell detachment from extracellular matrix, behaving as a critical mechanism in preventing adherent-independent cell growth and attachment to an inappropriate matrix, thus avoiding colonizing of distant organs. As anchorage-independent growth and epithelial-mesenchymal transition, two features associated with anoikis resistance, are vital steps during cancer progression and metastatic colonization, the ability of cancer cells to resist anoikis has now attracted main attention from the scientific community. Cancer cells develop anoikis resistance due to several mechanisms, including change in integrins' repertoire allowing them to grow in different niches, activation of a plethora of inside-out pro-survival signals as over-activation of receptors due to sustained autocrine loops, oncogene activation, growth factor receptor overexpression, or mutation/upregulation of key enzymes involved in integrin or growth factor receptor signaling. In addition, tumor microenvironment has also been acknowledged to contribute to anoikis resistance of bystander cancer cells, by modulating matrix stiffness, enhancing oxidative stress, producing pro-survival soluble factors, triggering epithelial-mesenchymal transition and self-renewal ability, as well as leading to metabolic deregulations of cancer cells. All these events help cancer cells to inhibit the apoptosis machinery and sustain pro-survival signals after detachment, counteracting anoikis and constituting promising targets for anti-metastatic pharmacological therapy. This article is part of a Special Section entitled: Cell Death Pathways.
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Anoikis , Progressão da Doença , Neoplasias/patologia , Transdução de Sinais , Animais , Citoproteção , Humanos , Metástase NeoplásicaRESUMO
Context Osteopathic manipulative medicine (OMM) has been claimed to be effective in various human disorders and conditions. There have been many anecdotal claims to lend credence to the efficacy of this treatment modality. Recently, much work has been done in evidence-based, government-funded projects, and clinical trials in OMM research, and these studies have further demonstrated the efficacy of OMM as direct, integrated, or complementary mechanisms in treating various conditions. Objectives As the field of OMM research has grown significantly in the past few years, we set out to analyze the peer-reviewed publications on OMM in human disorders between January 2018 and December 2022. Methods We used keywords and terms which included "osteopath," "osteopathic," osteopathic manipulative medicine," "osteopathic manipulative treatment," and "disorder," to systematically sample two public databases, PubMed and Science Direct. After the first query was recorded, we then applied more specific and stringent criteria to identify publications that (a) were written in English, (b) contained at least one human disorder/condition treated by OMM, (c) were co-authored by at least one osteopathic physician-scientist, and (d) contained at least one OMM technique. Results Our initial sampling of databases resulted in 404 publications. After applying our screening criteria, we identified and analyzed 249 (62%; 249/404) qualified publications in "OMM and Human Disorders" We then categorized them into (a) types of publications, (b) country origins of corresponding author(s), (c) groups of disorder and condition, (d) classification of the OMM used, and (e) relating the treated conditions with the five models of OMM. We found that in the 249 publications, 158 (63%) are research articles, 66 (27%) review papers, and 25 (10%) case reports. In addition, nine countries, the United States, Italy, Brazil, Spain, France, Germany, Canada, the United Kingdom (UK), and Australia contributed most of the publications of OMM. VOSviewer analysis identified a wide range of human disorders that were effectively treated with OMM. These included musculoskeletal, low back pain, neurological, headache, inflammation (including autoimmune conditions, COVID-19, lymphatic drainage), neonate/preterm infant disorders, anxiety, and dizziness. Conclusions Our comprehensive analysis showed that there has been a significant increase in peer-reviewed OMM publications in recent years, led by the United States osteopathic physician-scientists and European osteopathic scientists. OMM was found effective in treating not only common conditions such as pneumonia, low back pain, and musculoskeletal disorders, but also disorders such as inflammation, dizziness, headache, anxiety, and neonate/preterm infant disorders.
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CONTEXT: Deformational plagiocephaly (DP) is on the rise in pediatric patients. The current standard of care recommended for management is repositioning with possible addition of cranial orthoses. However, strong data are lacking to support these recommendations. Osteopathic manipulative treatment (OMT) is another treatment option for DP that is also lacking evidential support. OBJECTIVES: This retrospective chart review study investigated the effects of OMT at restoring a more symmetrical cranial bone configuration in children with DP. METHODS: A retrospective chart review was performed on medical records of patients with a diagnosis of DP from three private practices over a 4-year period from September 2017 to December 2021. Inclusion criteria were diagnoses of DP by a referring physician and aged 10 months or less at the time of initial evaluation and treatment. Patients were excluded if they had confounding diagnoses such as genetic syndromes or severe torticollis. A total of 26 patients met these criteria, and their records were reviewed. The main outcome reviewed was anthropometric assessment of the cranium, mainly the cranial vault asymmetry index (CVAI). RESULTS: Participants demonstrated a mean CVAI - a measure that determines the severity of DP - of 6.809 (±3.335) (Grade 3 severity) at baseline, in contrast to 3.834 (±2.842) (Grade 2 severity) after a series of OMT treatments. CVAI assessment after OMT reveals statistically significant (p≤0.001) decreases in measurements of skull asymmetry and occipital flattening. No adverse events were reported throughout the study period. CONCLUSIONS: The application of OMT has shown potential benefit for reducing cranial deformity in patients with DP.
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Osteopatia , Plagiocefalia , Criança , Humanos , Estudos RetrospectivosRESUMO
Patellofemoral pain syndrome (PFPS) is among the most common causes of musculoskeletal pain in the United States. It is defined as retropatellar or peripatellar pain that is reproduced with functional activities that load the patellofemoral joint in a flexed position, such as stair climbing or squatting. While it presents in both adolescents and adults, it is commonly found in physically active individuals, such as athletes and military recruits. Exploring the role of osteopathic manipulative treatment (OMT) in PFPS is of particular interest given the absence of a definitive treatment and the poor long-term prognosis associated with PFPS. This meta-analysis includes three studies exploring the use of OMT to reduce pain in patients suffering from PFPS and exploring the efficacy of OMT as a primary intervention. In these studies, pain assessments, pre-treatment, and post-treatment follow-up of at least 30 days were performed using a 10-cm visual analog scale (VAS). The mean difference in pain between OMT and no treatment (NT) groups using the random effects model was -3.95 (-6.39; -1.50) with a p<0.01, suggesting OMT resulted in significant knee pain reduction in those with PFPS. A measure of heterogeneity, known as I2, was found to be high at 97%, which suggests caution should be taken when interpreting the overall results. Given the lack of definitive treatment and the poor long-term prognosis for PFPS, the authors suggest OMT provides an effective option for pain relief in patients with PFPS. Further research is needed to provide results that may be more clinically applicable or valuably interpreted.
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Combining the use of cells with sparse cristae marked with IMP-EGFP and short pulsed sub-saturating fluorescence excitation (non-saturation fluorescence microscopy/NSFM) revealed inhomogeneous fluorescence distribution along mitochondria in living cells. Also the matrix located TMRE was distributed non-uniformly and at least in part filling the gaps between the IMP-EGFP fluorescence: fluorescence intensities are modulated in space and time in part in an antidromic manner. The spatial modulations can be interpreted to represent cristae/matrix distributions. The temporal fluctuations of fluorescence vary within 0.3-3s. Because most peak positions of IMP fluorescence remain stationary up to at least several minutes, temporal intensity modulations may result from varying emissions related to the degree of excitation and/or represent wobbling of cristae, i.e. lateral movements, bending or size changes. Modulations by noise and non-saturated excitation have been reduced by 3 steps of deconvolution followed by averaging 4 images. This allowed a final temporal resolution of 150ms. Disappearance of cristae or formation of new ones takes place within a few seconds, but these are rare events. Thus position of cristae seems to be rather stable, but they regularly disassemble close to fission sites. Treatment with oligomycin strongly reduces "wobbling" activity.
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Células Endoteliais da Veia Umbilical Humana/ultraestrutura , Membranas Mitocondriais/ultraestrutura , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Microscopia de Fluorescência , Dinâmica Mitocondrial , Membranas Mitocondriais/efeitos dos fármacos , Oligomicinas/farmacologia , Forma das Organelas , Compostos Organometálicos/química , Compostos Organometálicos/metabolismoRESUMO
Cigarette smoke causes direct oxidative DNA damage as well as indirect damage through inflammation. Epidemiological studies show a strong relationship between secondhand smoke and cancer; however, the mechanisms of secondhand smoke-induced cancer are not well understood. Animal models with either (i) deficient oxidative DNA damage repair, or (ii) a decreased capacity to combat oxidative stress may help determine the pathways important in mitigating damage caused by smoke. In this study, we used mice lacking Ogg1 and Myh, both of which are involved in base excision repair by removing oxidatively damaged DNA bases. Gclm-deficient mice, which have decreased levels of glutathione (GSH), were used to look at the role of smoke-induced oxidative damage. Ex vivo experiments show significantly elevated levels of DNA single-strand breaks and chromosomal aberrations in peripheral blood lymphocytes from Ogg1(-/-)Myh(-/-) double knockout mice compared to wild type (WT) mice after 24h of exposure to cigarette smoke extract (CSE). The average γH2AX foci per cell was significantly elevated 3h after exposure to CSE in cells from Ogg1(-/-)Myh(-/-) double knockout mice compared to wildtype mice. In vivo we found that all mice had increased markers of DNA damage after exposure to side-stream tobacco smoke (SSTS). Ogg1(-/-)Myh(-/-) and Gclm(-/-) mice had altered levels of peripheral blood glutathione after SSTS exposure whereas wild type mice did not. This may be due to differential regulation of glutathione synthesis in the lung. We also found that Ogg1(-/-)Myh(-/-) mice had a decreased lifespan after oral gavage with benzo[a]pyrene compared to wildtype mice and sham-exposed Ogg1(-/-)Myh(-/-) mice. Our results are important in investigating the roles of oxidative stress and oxidative DNA damage repair in cigarette smoke-induced cancers and characterizing the role of genetic polymorphisms in smoke-related disease susceptibility.
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Células Sanguíneas/efeitos dos fármacos , Distúrbios no Reparo do DNA/genética , Glutationa/deficiência , Estresse Oxidativo/genética , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Células Sanguíneas/metabolismo , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , DNA Glicosilases/genética , Distúrbios no Reparo do DNA/sangue , Distúrbios no Reparo do DNA/patologia , Feminino , Glutamato-Cisteína Ligase/genética , Glutationa/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo/efeitos dos fármacosRESUMO
Lymphotropic nanoparticle magnetic resonance imaging (LNMRI) utilises ultrasmall paramagnetic iron nanoparticles (USPIOs) for imaging of metastatic lymph nodes in patients afflicted with cancer. LNMRI has been shown to be a highly effective and accurate way to diagnose metastasis in humans but has not been commonly reported on in veterinary medicine. USPIOs are phagocytised by macrophages and then localised to lymph nodes where they create a susceptibility artefact on gradient echo MRI sequences. In this study dogs (n = 24) with naturally occurring head and neck tumours were imaged with LNMRI then had mandibular and retropharyngeal lymph nodes extirpated for histological analysis. Subjective and objective analysis of the LNMRI images was performed and imaging results compared to histology as the gold standard. A total of 149 lymph nodes were included in this study. The overall sensitivity, specificity and accuracy was 64%, 94.4% and 89.3% respectively. However, if dogs with mast cell tumours were excluded from analysis the sensitivity, specificity and accuracy rose to 85.7%, 95.7% and 94.6%. LNMRI is potentially an accurate way to determine the presence of lymph node metastasis in dogs with some types of head and neck tumours. However, LNMRI has only moderate accuracy in dogs with oral or mucocutaneous mast cell tumours in this region.
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Doenças do Cão , Neoplasias de Cabeça e Pescoço , Humanos , Cães , Animais , Sensibilidade e Especificidade , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Imageamento por Ressonância Magnética/veterinária , Imageamento por Ressonância Magnética/métodos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/veterinária , Neoplasias de Cabeça e Pescoço/patologia , Meios de ContrasteRESUMO
BACKGROUND: Bacteria and their viruses, bacteriophages, are the most abundant entities of the gut microbiota, a complex community of microorganisms associated with human health and disease. In this ecosystem, the interactions between these two key components are still largely unknown. In particular, the impact of the gut environment on bacteria and their associated prophages is yet to be deciphered. RESULTS: To gain insight into the activity of lysogenic bacteriophages within the context of their host genomes, we performed proximity ligation-based sequencing (Hi-C) in both in vitro and in vivo conditions on the 12 bacterial strains of the OMM12 synthetic bacterial community stably associated within mice gut (gnotobiotic mouse line OMM12). High-resolution contact maps of the chromosome 3D organization of the bacterial genomes revealed a wide diversity of architectures, differences between environments, and an overall stability over time in the gut of mice. The DNA contacts pointed at 3D signatures of prophages leading to 16 of them being predicted as functional. We also identified circularization signals and observed different 3D patterns between in vitro and in vivo conditions. Concurrent virome analysis showed that 11 of these prophages produced viral particles and that OMM12 mice do not carry other intestinal viruses. CONCLUSIONS: The precise identification by Hi-C of functional and active prophages within bacterial communities will unlock the study of interactions between bacteriophages and bacteria across conditions (healthy vs disease). Video Abstract.
Assuntos
Bacteriófagos , Prófagos , Camundongos , Humanos , Animais , Prófagos/genética , Ecossistema , Bacteriófagos/genética , Genômica , Cromossomos , Bactérias/genéticaRESUMO
CONTEXT: Medical students with no previous experience may find it difficult to identify and palpate bony landmarks while learning physical examination skills. In a study of 168 medical schools, 72.6â¯% have indicated that they are utilizing ultrasound in their curriculum. Although the integration of ultrasound curriculum has become more widespread, the depth of instruction is inconsistent. Ultrasound is not commonly taught in conjunction with palpation of bony landmarks in osteopathic structural examination. OBJECTIVES: The objective of this analysis was to identify whether utilizing ultrasound assistance in teaching palpation of specific thoracic vertebral bony landmarks would improve palpation accuracy in first-year medical students with no previous palpatory experience. METHODS: First-year medical students were given video instructions to palpate and identify a thoracic vertebral transverse process and to mark it with invisible ink. The participants were then taught and instructed to utilize ultrasound to identify the same landmark and mark it with a different color. The accuracy of palpation was measured with digital calipers. RESULTS: A test of the overall hypothesis that participants will show improved accuracy utilizing ultrasound compared with hand palpation was not significant (F=0.76, p>0.05). When separating students into groups according to patient body mass index (BMI), however, there was a trend toward significance (F=2.90, p=0.071) for an interaction effect between patient BMI and the repeated measures variable of palpation/ultrasound. When looking specifically at only those participants working with a normal BMI patient, there was a significant improvement in their accuracy with the use of ultrasound (F=7.92, p=0.017). CONCLUSIONS: The analysis found increased accuracy in bony landmark identification in untrained palpators utilizing ultrasound vs. palpation alone in a normal BMI model, but not in obese or overweight BMI models. This study shows promise to the value that ultrasound may have in medical education, especially with respect to early palpation training and landmark identification.