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101.

Objective

To analyze the clinical manifestations and response to treatment in a cohort of adult patients presenting with recurrent inflammatory attacks and carrying low-penetrance TNFRSF1A variants, as well as to provide data on their long-term follow-up.

Methods

We performed a retrospective chart review of 36 patients carrying low-penetrance TNFRSF1A variants. Moreover, 60 genetically negative patients treated for recurrent inflammatory attacks and 13 patients with structural TNFRSF1A mutations were also analyzed. Detailed demographic and clinical data were collected at the time of molecular screening and at each follow-up visit. Treatments and markers of inflammation were also assessed.

Results

Individuals with low-penetrance TNFRSF1A variants have a lower family history for inflammatory attacks and present with a later disease onset compared with patients with structural mutations, but do not differ, in this respect, with genetically negative individuals. Moreover, low-penetrance variants are less frequently associated with a chronic disease course, with clinical manifestations such as abdominal pain and myalgia, and with amyloidosis. A distinctive clinical feature is a higher rate of pericarditis. Interestingly, mutation-negative patients were found to present with a significant history of recurrent pharyngitis during childhood. Patients with low-penetrance variants are mostly managed with short courses of steroids or non-steroidal anti-inflammatory drugs on attacks. Although the need for a biological treatment is significantly lower compared with patients with structural mutations, still approximately 20% of individuals with recurrent inflammatory attacks carrying low-penetrance variants ultimately require these therapies.

Conclusions

Our study confirms that low-penetrance TNFRSF1A variants can be associated with an autoinflammatory phenotype. Although a chronic disease course is rarely observed, some patients ultimately benefit from a biological treatment.  相似文献   
102.
Although updated consensus guidelines, and effective therapies, are available for management of gout, suboptimal management remains an issue. Barriers were identified and addressed as part of a dedicated, structured gout clinic. More frequent appointments resulted in a faster rate of serum urate reduction, and the clinic provided the opportunity for the education of both patients and general practitioners in the management of gout.  相似文献   
103.
Malignant mesothelioma (MM) is a highly aggressive form of cancer, has a long latency period, and is resistant to chemotherapy. It is extremely fatal, with a mean survival of less than one year. The development of MM is strongly correlated with exposure to asbestos and erionite, as well as to simian virus 40. Although various countries have banned the use of asbestos, MM has proven to be difficult to control and there appears to be a trend toward an increase in its incidence in the years to come. In Brazil, MM has not been widely studied from a genetic or biochemical standpoint. In addition, there have been few epidemiological studies of the disease, and the profile of its incidence has yet to be well established in the Brazilian population. The objective of this study was to review the literature regarding the processes of malignant transformation, as well as the respective mechanisms of tumorigenesis, in MM.  相似文献   
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The plasma membrane of cardiac myocytes presents complex invaginations known as the transverse-axial tubular system (TATS). Despite TATS's crucial role in excitation-contraction coupling and morphological alterations found in pathological settings, TATS's electrical activity has never been directly investigated in remodeled tubular networks. Here we develop an ultrafast random access multiphoton microscope that, in combination with a customly synthesized voltage-sensitive dye, is used to simultaneously measure action potentials (APs) at multiple sites within the sarcolemma with submillisecond temporal and submicrometer spatial resolution in real time. We find that the tight electrical coupling between different sarcolemmal domains is guaranteed only within an intact tubular system. In fact, acute detachment by osmotic shock of most tubules from the surface sarcolemma prevents AP propagation not only in the disconnected tubules, but also in some of the tubules that remain connected with the surface. This indicates that a structural disorganization of the tubular system worsens the electrical coupling between the TATS and the surface. The pathological implications of this finding are investigated in failing hearts. We find that AP propagation into the pathologically remodeled TATS frequently fails and may be followed by local spontaneous electrical activity. Our findings provide insight on the relationship between abnormal TATS and asynchronous calcium release, a major determinant of cardiac contractile dysfunction and arrhythmias.  相似文献   
106.
We introduce a new approach to improve structural and dynamical determination of large metalloproteins using solid-state nuclear magnetic resonance (NMR) with (1)H detection under ultrafast magic angle spinning (MAS). The approach is based on the rapid and sensitive acquisition of an extensive set of (15)N and (13)C nuclear relaxation rates. The system on which we demonstrate these methods is the enzyme Cu, Zn superoxide dismutase (SOD), which coordinates a Cu ion available either in Cu(+) (diamagnetic) or Cu(2+) (paramagnetic) form. Paramagnetic relaxation enhancements are obtained from the difference in rates measured in the two forms and are employed as structural constraints for the determination of the protein structure. When added to (1)H-(1)H distance restraints, they are shown to yield a twofold improvement of the precision of the structure. Site-specific order parameters and timescales of motion are obtained by a gaussian axial fluctuation (GAF) analysis of the relaxation rates of the diamagnetic molecule, and interpreted in relation to backbone structure and metal binding. Timescales for motion are found to be in the range of the overall correlation time in solution, where internal motions characterized here would not be observable.  相似文献   
107.
108.
Objective: To compare the anesthetic action of 0.5% bupivacaine in relation to 4% articaine, both with 1:200,000 epinephrine, in the surgical removal of lower third molars. As a secondary objective hemodynamic changes using both anesthetics were analyzed. Study Design: Triple-blind crossover randomized clinical trial. Eighteen patients underwent bilateral removal of impacted lower third molars using 0.5% bupivacaine or 4% articaine in two different appointments. Preoperative, intraoperative and postoperative variables were recorded. Differences were assessed with McNemar tests and repeated measures ANOVA tests. Results: Both solutions exhibited similar latency times and intraoperative efficacy. Statistical significant lower pain levels were observed with bupivacaine between the fifth (p=0.011) and the ninth (p=0.007) postoperative hours. Bupivacaine provided significantly longer lasting soft tissue anesthesia (p<0.05). Systolic blood pressure and heart rate values were significantly higher with articaine. Conclusions: Bupivacaine could be a valid alternative to articaine especially due to its early postoperative pain prevention ability. Key words:Bupivacaine, articaine, third molar, anesthesia, postoperative pain.  相似文献   
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