RESUMO
Catechins are a class of polyphenols and have high anti-bacterial activity against various microorganisms. Here, we report the mechanism for antibacterial activity of epigallocatechin gallate (EGCg) against Gram-positive bacteria Bacillus subtilis, which is highly sensitive to EGCg. Transmission electron microscope analysis revealed that deposits containing EGCg were found throughout the cell envelope from the outermost surface to the outer surface of cytoplasmic membrane. Aggregating forms of proteins and EGCg were identified as spots that disappeared or showed markedly decreased intensity after the treatment with EGCg compared to the control by two-dimensional electrophoresis. Among the identified proteins included 4 cell surface proteins, such as oligopeptide ABC transporter binding lipoprotein, glucose phosphotransferase system transporter protein, phosphate ABC transporter substrate-binding protein, and penicillin-binding protein 5. Observations of glucose uptake of cells and cell shape B. subtilis after the treatment with EGCg suggested that EGCg inhibits the major functions of these proteins, leading to growth inhibition of B. subtilis.
Assuntos
Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Catequina/análogos & derivados , Sequência de Aminoácidos , Bacillus subtilis/metabolismo , Bacillus subtilis/fisiologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Catequina/química , Catequina/metabolismo , Catequina/farmacologia , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Glucose/metabolismo , Lipoproteínas/química , Lipoproteínas/metabolismo , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Oxigênio/metabolismo , Esporos Bacterianos/efeitos dos fármacosRESUMO
OBJECTIVES: It is very difficult for dental professionals to objectively assess tooth brushing skill of patients, because an obvious index to assess the brushing motion of patients has not been established. The purpose of this study was to quantitatively evaluate toothbrush and arm-joint motion during tooth brushing. MATERIALS AND METHODS: Tooth brushing motion, performed by dental hygienists for 15 s, was captured using a motion-capture system that continuously calculates the three-dimensional coordinates of object's motion relative to the floor. The dental hygienists performed the tooth brushing on the buccal and palatal sides of their right and left upper molars. The frequencies and power spectra of toothbrush motion and joint angles of the shoulder, elbow, and wrist were calculated and analyzed statistically. RESULTS: The frequency of toothbrush motion was higher on the left side (both buccal and palatal areas) than on the right side. There were no significant differences among joint angle frequencies within each brushing area. The inter- and intra-individual variations of the power spectrum of the elbow flexion angle when brushing were smaller than for any of the other angles. CONCLUSIONS: This study quantitatively confirmed that dental hygienists have individual distinctive rhythms during tooth brushing. All arm joints moved synchronously during brushing, and tooth brushing motion was controlled by coordinated movement of the joints. The elbow generated an individual's frequency through a stabilizing movement. CLINICAL RELEVANCE: The shoulder and wrist control the hand motion, and the elbow generates the cyclic rhythm during tooth brushing.
Assuntos
Braço/fisiologia , Movimento/fisiologia , Escovação Dentária , Adulto , Higienistas Dentários , Feminino , Humanos , Imageamento Tridimensional , MasculinoRESUMO
Microglia, the resident immune cells of the central nervous system, are constitutively mobile cells that undergo rapid directional movement toward sites of tissue disruption. However, transcriptional regulatory mechanisms of microglial motility remain unknown. In the present study, we show that interferon regulatory factor-8 (IRF8) regulates microglial motility. We found that ATP and complement component, C5a, induced chemotaxis of IRF8 wild-type microglia. However, these responses were markedly suppressed in microglia lacking IRF8 (Irf8 (-/-)). In a consistent manner, phosphorylation of Akt (which plays a crucial role in ATP-induced chemotaxis) was abolished in Irf8 (-/-)microglia. Real-time polymerase chain reaction analysis revealed that motility-related microglial genes such as P2Y12 receptor were significantly suppressed in Irf8 (-/-)microglia. Furthermore, Irf8 (-/-)microglia exhibited a differential expression pattern of nucleotide-degrading enzymes compared with their wild-type counterparts. Overall, our findings suggest that IRF8 may regulate microglial motility via the control of microglial gene expression.
Assuntos
Movimento Celular/fisiologia , Fatores Reguladores de Interferon/biossíntese , Microglia/fisiologia , Transcrição Gênica/fisiologia , Animais , Células Cultivadas , Camundongos , Camundongos KnockoutRESUMO
BACKGROUND: Previous studies have examined when activities of daily living (ADL) recovery more than six months after surgery can be predicted, and how much accuracy the predictors have. OBJECTIVE: The purpose of this study was to determine the predictors of ADL decline and evaluate their accuracies one year post-operation for hip-fracture patients. METHODS: We studied patients who underwent hip fracture surgery and were able to walk independently pre-operatively. The predictors of ADL declined one year post-operation, as analyzed using data of the basic medical attributes of the patients, including pain, 30-s chair-stand test, dementia [using the Revised Hasegawa Dementia Scale (HDS-R)], and walking/mobility style [using Barthel Index (BI)]. Using a receiver operating curve (ROC) curve, the cut-off value for each significant predictor was determined in the logistic regression analysis. To calculate the cut-off values and diagnostic performances of each of the extraction factors. RESULTS: The data of 36 patients were collected over a period of one year. The prior probability of ADL decline at one year post-operation was 44.4%. The results of logistic regression analyses showed that the score of HDS-R at admission and the walking/mobility BI score at three weeks post-operation were significant predictors of the one year post-operative decline in ADL. The results of the ROC analyses showed that the cut-off value of the HDS-R score at admission was < 23 points. The posterior probability increased to 62.0%. In contrast, the cut-off value of the walking/mobility BI score was 0 points. The posterior probability increased to 91.0%. CONCLUSION: The ADL decline of the patients who underwent hip fracture surgery at one year after surgery can be predicted at three weeks post-operation.
Assuntos
Atividades Cotidianas , Fraturas do Quadril/reabilitação , Limitação da Mobilidade , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas do Quadril/cirurgia , Hospitalização , Humanos , Masculino , Período Pós-Operatório , Estudos Prospectivos , CaminhadaRESUMO
P2X4 receptors (P2X4R) are a family of ATP-gated non-selective cation channels. We previously demonstrated that activation of P2X4R in spinal microglia is crucial for neuropathic pain, a highly debilitating chronic pain condition, suggesting that P2X4R is a potential therapeutic target for treating neuropathic pain. Thus, the identification of a compound that has a potent inhibitory effect on P2X4R is an important clinical challenge. In the present study, we screened a chemical library of clinically approved drugs and show for the first time that duloxetine, a serotonin and noradrenaline reuptake inhibitor, has an inhibitory effect on rodent and human P2X4R. In primary cultured microglial cells, duloxetine also inhibited P2X4R-, but not P2X7R-, mediated responses. Moreover, intrathecal administration of duloxetine in a model of neuropathic pain produced a reversal of nerve injury-induced mechanical allodynia, a cardinal symptom of neuropathic pain. In rats that were pretreated with a serotonin-depleting agent and a noradrenaline neurotoxin, the antiallodynic effect of duloxetine was reduced, but still remained. Based on these results, we suggest that, in addition to duloxetine's primary inhibitory action on serotonin and noradrenaline transporters, an inhibitory effect on P2X4R may be involved at least in part in an antiallodynic effect of intrathecal duloxetine in a model of neuropathic pain.
Assuntos
Cloridrato de Duloxetina/farmacologia , Microglia/efeitos dos fármacos , Neuralgia/prevenção & controle , Traumatismos dos Nervos Periféricos/complicações , Antagonistas do Receptor Purinérgico P2X/farmacologia , Animais , Masculino , Microglia/metabolismo , Neuralgia/etiologia , Ratos , Ratos Wistar , Receptores Purinérgicos P2X4/metabolismoRESUMO
Accumulating evidence indicates that peripheral nerve injury (PNI) activates spinal microglia that are necessary for neuropathic pain. Recent studies using bone marrow (BM) chimeric mice have reported that after PNI, circulating BM-derived cells infiltrate into the spinal cord and differentiate into microglia-like cells. This raises the possibility that the population of spinal microglia after PNI may be heterogeneous. However, the infiltration of BM cells in the spinal cord remains controversial because of experimental adverse effects of strong irradiation used for generating BM chimeric mice. In this study, we evaluated the PNI-induced spinal infiltration of BM-derived cells not only by irradiation-induced myeloablation with various conditioning regimens, but also by parabiosis and mice with genetically labelled microglia, models without irradiation and BM transplantation. Results obtained from these independent approaches provide compelling evidence indicating little contribution of circulating BM-derived cells to the population of spinal microglia after PNI.
Assuntos
Células da Medula Óssea/citologia , Microglia/patologia , Neuralgia/etiologia , Traumatismos dos Nervos Periféricos/complicações , Animais , Células da Medula Óssea/metabolismo , Células da Medula Óssea/efeitos da radiação , Transplante de Medula Óssea , Modelos Animais de Doenças , Raios gama/efeitos adversos , Masculino , Camundongos , Microglia/citologia , Microglia/metabolismo , Traumatismos dos Nervos Periféricos/etiologiaRESUMO
In the beverage industry, peracetic acid has been increasingly used as a disinfectant for the filling machinery and environment due to merits of leaving no residue, it is safe for humans, and its antiseptic effect against fungi and endospores of bacteria. Recently, Chaetomium globosum and Chaetomium funicola were reported resistant to peracetic acid; however, little is known concerning the detail of peracetic acid resistance. Therefore, we assessed the peracetic acid resistance of the species of Chaetomium and related genera under identical conditions and made a thorough observation of the microstructure of their ascospores by transmission electron microscopy. The results of analyses revealed that C. globosum and C. funicola showed the high resistance to peracetic acid (a 1-D antiseptic effect after 900 s and 3-D antiseptic effect after 900 s) and had thick cell walls of ascospores that can impede the action mechanism of peracetic acid. We also developed specific primers to detect the C. globosum clade and identify C. funicola by using PCR to amplify the ß-tubulin gene. PCR with the primer sets designed for C. globosum (Chae 4F/4R) and C. funicola (Cfu 2F/2R) amplified PCR products specific for the C. globosum clade and C. funicola, respectively. PCR with these two primer sets did not detect other fungi involved in food spoilage and environmental contamination. This detection and identification method is rapid and simple, with extremely high specificity.