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PURPOSE: Prosthetic materials and bone present quite different mechanical properties. Consequently, mandible reconstruction with metallic materials (or a mandible condyle implant) modifies the physiologic behavior of the mandible ...
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PURPOSE: Prosthetic materials and bone present quite different mechanical properties. Consequently, mandible reconstruction with metallic materials (or a mandible condyle implant) modifies the physiologic behavior of the mandible (stress, strain patterns, and condyle displacements). The changing of bone strain distribution results in an adaptation of the temporomandibular joint, including articular contacts. MATERIALS AND METHODS: Using a validated finite element model, the natural mandible strains and condyle displacements were evaluated. Modifications of strains and displacements were then assessed for 2 different temporomandibular joint implants. Because materials and geometry play important key roles, mechanical properties of cortical bone were taken into account in models used in finite element analysis. RESULTS: The finite element model allowed verification of the worst loading configuration of the mandibular condyle. Replacing the natural condyle by 1 of the 2 tested implants, the results also show the importance of the implant geometry concerning biomechanical mandibular behavior. The implant geometry and stiffness influenced mainly strain distribution. CONCLUSION: The different forces applied to the mandible by the elevator muscles, teeth, and joint loads indicate that the finite element model is a relevant tool to optimize implant geometry or, in a subsequent study, to choose a more suitable distribution of the screws. Bone screws (number and position) have a significant influence on mandibular behavior and on implant stress pattern. Stress concentration and implant fracture must be avoided.
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Designing a temporomandibular joint (TMJ) total prosthesis requires the assessment of joint displacements for open/close movements. Current knowledge presents disc-condyle motions as involving both translation and rotation but the...
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Designing a temporomandibular joint (TMJ) total prosthesis requires the assessment of joint displacements for open/close movements. Current knowledge presents disc-condyle motions as involving both translation and rotation but there may be substantial variations from human to human. The aim of this study is to discriminate objective kinematic characters amongst thirty-two volunteers. The displacements are determined using 3D video analysis. The ratio between rotation and translation can be defined by introducing a coefficient. This coefficient varies relatively to the opening amplitude and presents the same dispersion rate whatever the variations. Then it allows to discriminate amongst volunteers, regardless of any jaw opening values. Three groups can be isolated relatively to three kinematic models: a translatory preponderant group, a common group and a rotatory preponderant group. All subjects in the first group present concomitant rotatory/translatory displacements up to maximal opening. The other two groups present variations due to different quasi-pure rotation phases at the end of the opening movement. These investigations will make it possible to establish a correlation between the kinematic characters and the disc-condyle trajectories. The disc-condyle glides along the temporal facet and the condyle centre describes the tubercular morphology. The temporal facet geometry, useful for the TMJ prosthesis design, will be studied in a next paper.
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Grapevine leafroll-associated virus 3 (GLRaV-3) is a mealybug-transmissible ampelovirus. Though the transmission mechanism has been described as semipersistent on the basis of temporal parameters, definitive proof of this mechanis...
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Grapevine leafroll-associated virus 3 (GLRaV-3) is a mealybug-transmissible ampelovirus. Though the transmission mechanism has been described as semipersistent on the basis of temporal parameters, definitive proof of this mechanism has never been provided. In the present study, we carried out preliminary assays to establish the location of the virus in its vector, Planococcus citri. After dissecting the insects, GLRaV-3 was detected by means of IC-RT-PCR in the salivary glands, intestine and Malpighian tubes, but not in the sucking apparatus. Immunogold labelling of the capsid protein revealed the presence of the virus in some cells of the primary salivary glands, but not in the alimentary channel of the stylet, or in the accessory salivary glands. The strong labelling of the electron-dense secretion vesicles in some cells of the primary salivary glands, together with the non-detection of the virus in the sucking apparatus suggests that the transmission mechanism may be different from that previously described. We propose a circulative transmission mechanism based on a specific transportation route for the viral particles from the midgut or hindgut to the salivary glands. As the transmission mechanism is generally a common feature of a viral genus, the existence of a circulative transmission mechanism for other mealybug-transmitted ampeloviruses is expected. Organ by organ analysis of GLRaV-1, another ampelovirus not transmissible by P. citri, showed the absence of the virus in the salivary glands, thus providing further, though indirect, evidence in favour of circulative transmission for this virus genus..
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p19 RNA binding protein from the Carnation Italian ringspot virus (CIRV) is an RNA-silencing suppressor that binds small interfering RNA (siRNA) with high affinity. We created a bifunctional p19 fusion protein with an N-terminal m...
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p19 RNA binding protein from the Carnation Italian ringspot virus (CIRV) is an RNA-silencing suppressor that binds small interfering RNA (siRNA) with high affinity. We created a bifunctional p19 fusion protein with an N-terminal maltose binding protein (MBP), for protein purification, and a C-terminal chitin binding domain (CBD) to bind p19 to chitin magnetic beads. The fusion protein binds dsRNAs in the size range of 20-23 nucleotides, but does not bind ssRNA or dsDNA. Relative affinities of the p19 fusion protein for different-length RNA and DNA substrates were determined. Binding specificity of the p19 fusion protein for small dsRNA allows detection of miRNA:RNA probe duplexes. Using radioactive RNA probes, we were able to detect low levels of miRNAs in the sub-femtomole range and in the presence of a million-fold excess of total RNA. Detection is linear over three logs. Unlike most nucleic acid detection methods, p19 selects for RNA hybrids of correct length and structure. Rules for designing optimal RNA probes for p19 detection of miRNAs were determined by in vitro binding of 18 different dsRNA oligos to p19. These studies demonstrate the potential of p19 fusion protein to detect miRNAs and isolate endogenous siRNAs.
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OBJECTIVES: We undertook a systematic literature review as a background to the European League Against Rheumatism (EULAR) recommendations for conducting clinical trials in anti-neutrophil cytoplasm antibody associated vasculitis (...
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OBJECTIVES: We undertook a systematic literature review as a background to the European League Against Rheumatism (EULAR) recommendations for conducting clinical trials in anti-neutrophil cytoplasm antibody associated vasculitis (AAV), and to assess the quality of evidence for outcome measures in AAV. METHODS: Using a systematic Medline search, we categorised the identified studies according to diagnoses. Factors affecting remission, relapse, renal function and overall survival were identified. RESULTS: A total of 44 papers were reviewed from 502 identified by our search criteria. There was considerable inconsistency in definitions of end points. Remission rates varied from 30% to 93% in Wegener granulomatosis (WG), 75% to 89% in microscopic polyangiitis (MPA) and 81% to 91% in Churg-Strauss syndrome (CSS). The 5-year survival for WG, MPA and CSS was 74-91%, 45-76% and 60-97%. Relapse (variably defined) was common in the first 2 years but the frequency varied: 18% to 60% in WG, 8% in MPA, and 35% in CSS. The rate of renal survival in WG varied from 23% at 15 months to 23% at 120 months. METHOD: used to assess morbidity varied between studies. Ignoring the variations in definitions of the stage of disease, factors influencing remission, relapse, renal and overall survival included immunosuppressive therapy used, type of organ involvement, presence of ANCA, older age and male gender. CONCLUSIONS: Factors influencing remission, relapse, renal and overall survival include the type of immunosuppressive therapy used, pattern of organ involvement, presence of ANCA, older age and male gender. Methodological variations between studies highlight the need for a consensus on terminology and definitions for future conduct of clinical studies in AAV.
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OBJECTIVES: to evaluate the effect of two interventions on reducing antibiotic prescription in pharyngitis. METHODS: a prospective, non-randomized, before-after controlled study was carried out in primary care centres throughout S...
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OBJECTIVES: to evaluate the effect of two interventions on reducing antibiotic prescription in pharyngitis. METHODS: a prospective, non-randomized, before-after controlled study was carried out in primary care centres throughout Spain. General practitioners (GPs) registered all cases of pharyngitis during a 3 week period before and after two types of intervention in 2008 and 2009, respectively. Full intervention consisted of discussion sessions of the results of the first registry, courses for GPs, guidelines, patient information leaflets, workshops on rapid tests and the use of rapid antigen detection tests (RADTs) in their consulting offices. The physicians in the partial intervention group underwent all the above intervention except for the workshop, and RADTs were not provided. A control group was also included in 2009. Multilevel logistic regression was performed considering the prescription of antibiotics as the dependent variable. RESULTS: a total of 280 GPs registered cases with pharyngitis (70 partial intervention and 210 full intervention). Fifty-nine new physicians were included as a control group. A total of 6849 episodes of pharyngitis were registered. Antibiotic prescription was significantly lower after intervention for the full intervention group, but not for the partial intervention group. According to the multivariate model, in comparison with the control group, the odds ratio of antibiotic prescription after the intervention was 0.52 [95% confidence interval (95% CI) 0.23-1.18] in the partial intervention group and 0.23 (95% CI 0.11-0.47) in the full intervention group. CONCLUSIONS: intervention was beneficial for reducing the prescription of antibiotics, but was only statistically significant when the GPs were provided with RADTs.
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Acclimatization of sugarcane plantlets (Saccharum spp. hybrid) var. C91-301, micropropagated in temporary immersion bioreactors, was studied. When in vitro plantlets were transferred to acclimatization conditions, photosynthesis i...
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Acclimatization of sugarcane plantlets (Saccharum spp. hybrid) var. C91-301, micropropagated in temporary immersion bioreactors, was studied. When in vitro plantlets were transferred to acclimatization conditions, photosynthesis increased only slightly during the first 7 d. After this period, the increase was constant with only a small decline after transfer to uncontrolled external conditions. Production of fresh and dry weights, number of leaves and roots, leaf area, stomatal density and chlorophyll contents were evaluated during the acclimatization period. From day 14 on, sugarcane plantlets exhibited low but positive photosynthesis due to the new formation of leaves and roots. The increase in light intensity and the gradual reduction of relative humidity during acclimatization did not constitute inhibitory factors, as can be interpreted from the increased photosynthetic activity until 21 d. Stomatal density and leaf area after 21 d were also increased, while the chlorophyll content declined.
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