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Porphyromonas gingivalis secretes strong proteases called gingipains that are implicated in periodontal pathogenesis. Protein secretion systems common to other Gram-negative bacteria are lacking in P. gingivalis, but several proteins, including PorT, have been linked to gingipain secretion. Comparative genome analysis and genetic experiments revealed 11 additional proteins involved in gingipain secretion. Six of these (PorK, PorL, PorM, PorN, PorW, and Sov) were similar in sequence to Flavobacterium johnsoniae gliding motility proteins, and two others (PorX and PorY) were putative two-component system regulatory proteins. Real-time RT-PCR analysis revealed that porK, porL, porM, porN, porP, porT, and sov were down-regulated in P. gingivalis porX and porY mutants. Disruption of the F. johnsoniae porT ortholog resulted in defects in motility, chitinase secretion, and translocation of a gliding motility protein, SprB adhesin, to the cell surface, providing a link between a unique protein translocation system and a motility apparatus in members of the Bacteroidetes phylum.  相似文献   
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The purpose of this study was to investigate glenohumeral translation in-vivo during active shoulder abduction in the scapular plane. Three-dimensional (3D) models of 9 shoulders were created from CT scans. Fluoroscopic views aligned to the plane of the scapula were recorded during active arm abduction with neutral rotation. 3D motions were determined using model-based 3D-to-two-dimensional (2D) registration. Humeral translation was referenced to the glenoid center in the superior/inferior direction. The humerus moved an average of 1.7 mm superior with arm abduction, from an inferior location to the glenoid center. The humeral head was centered within 1 mm from the glenoid center above 80 degrees abduction. Variability in glenohumeral translation between shoulders decreased significantly from initial to final arm abduction. Our findings agree with some authors' observations of inferior-to-central translation of the humerus and behavior as a congruent ball and socket. We believe this information will help improve the understanding of shoulder function.  相似文献   
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A comparative study was conducted in elderly subjects with mild bronchial asthma to investigate the clinical usefulness of monotherapy with a leukotriene receptor antagonist in comparison to an inhaled corticosteroid. A total of 41 elderly patients aged 65 years or older with mild bronchial asthma, classified as being in severity step 1 and 2, were randomly assigned to the following two treatment groups: a pranlukast (CAS 103177-37-3, Onon) treatment group of 21 patients and an inhaled corticosteroid treatment group of 20 patients. Patients of the former group received pranlukast 450 mg daily and those of the latter group received fluticasone (CAS 90566-53-3) 200 microg daily for eight weeks. In the reference group, one patient was found to suffer from oral candidiasis 4 weeks after the start of the study. Therefore the evaluation was conducted on the remaining 19 participants. The evaluation parameters examined were obtained by keeping an asthma diary, determinations of PEF (peek expiratory flow), use frequency of beta2 stimulants, changes in symptom scores, and medication compliance. Further, measured before and after therapy were the ratio of peripheral blood eosinophils counts, serum ECP (eosinophils cationic protein), ECP levels induced sputum, and forced expiratory volume in one second (FEV1.0). As a result, in the time-course changes of symptoms scores and morning PEF, swift improvement was noted in the pranlukast group. Further, in the variables such as use frequency of beta2 stimulants, serum ECP levels, ECP levels induced sputum, and FEV1.0, an almost comparable level of improvement to the fluticasone group was demonstrated. From the above results, it was deemed that in elderly patients with mild bronchial asthma classified as steps 1 and 2, the pranlukast monotherapy, with superior medication compliance to inhaled therapy, would produce an equivalent level of clinical efficacy to the monotherapy with inhaled corticosteroid (fluticasone 200 microg daily).  相似文献   
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A series of eight 5,6-dihydro-4H-1,3-thiazine derivatives was synthesized by the BF3 x Et2O-catalyzed reaction of selected alpha,beta-unsaturated ketones with thiobenzamide at room temperature. The antimycobacterial activities of these compounds were determined against Mycobacterium tuberculosis H37Rv (ATCC 27294) using the Alamar blue susceptibility assay. Three compounds, 5-hydroxy-3-phenyl-4-aza-2-thiabicyclo[3.3.1]none-3-ene 3a, 4-hydroxy-4-methyl-6-pentyl-2-phenyl-5,6-dihydro-4H-1,3-thiazine 3b, and 4-ethyl-4-hydroxy-2-phenyl-5,6-dihydro-4H-1,3-thiazine 3c exhibited inhibitory activities of 97, 77 and 76%, respectively, at a concentration of 6.25 microg/ml. The actual MIC99 for the most active of these compounds, 3a, was also determined to be >6.25 microg/ml. These results, and especially those for 3a, suggest that 1,3-thiazines are potential lead compounds in the search for new antitubercular agents.  相似文献   
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Purpose: To assess the relationship between the prevalence and severity of conjunctivochalasis and pinguecula. Methods: Cross‐sectional, consecutive case study conducted at the university hospital of University of Tokyo Graduate School of Medicine. A total of 1061 patients aged from 1 to 94 years were enrolled. The grade and other parameters of conjunctivochalasis (classified into three locations: nasal, middle and temporal) and the grade of pinguecula located on the nasal or temporal conjunctiva were determined in all subjects. Patients were also divided into 5 or 10 age groups. Results: The severity of conjunctivochalasis affecting the nasal and temporal bulbar conjunctiva was significantly correlated with the grade of pinguecula located on the nasal and temporal conjunctiva in each age group (p < 0.05). Pinguecula was independently associated with conjunctivochalasis (nasal: odds ratio [OR] = 1.44; temporal: OR = 1.43) after adjustment for age. Conclusion: This was the first assessment of the relation between the grade of conjunctivochalasis and pinguecula in a large consecutive series of patients. Our results suggest that the prevalence and severity of conjunctivochalasis are related to the presence of pinguecula.  相似文献   
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