229 research outputs found

    Thermal stability and aggregation of sulfolobus solfataricus b-glycosidase are dependent upon the N-e-methylation of specific lysyl residues: critical role of in vivo post-translational modifications.

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    Methylation in vivo is a post-translational modification observed in several organisms belonging to eucarya, bacteria, and archaea. Although important implications of this modification have been demonstrated in several eucaryotes, its biological role in hyperthermophilic archaea is far from being understood. The aim of this work is to clarify some effects of methylation on the properties of β-glycosidase from Sulfolobus solfataricus, by a structural comparison between the native, methylated protein and its unmethylated counterpart, recombinantly expressed in Escherichia coli. Analysis by Fourier transform infrared spectroscopy indicated similar secondary structure contents for the two forms of the protein. However, the study of temperature perturbation by Fourier transform infrared spectroscopy and turbidimetry evidenced denaturation and aggregation events more pronounced in recombinant than in native β-glycosidase. Red Nile fluorescence analysis revealed significant differences of surface hydrophobicity between the two forms of the protein. Unlike the native enzyme, which dissociated into SDS-resistant dimers upon exposure to the detergent, the recombinant enzyme partially dissociated into monomers. By electrospray mapping, the methylation sites of the native protein were identified. A computational analysis of β-glycosidase three-dimensional structure and comparisons with other proteins from S. solfataricus revealed analogies in the localization of methylation sites in terms of secondary structural elements and overall topology. These observations suggest a role for the methylation of lysyl residues, located in selected domains, in the thermal stabilization of β-glycosidase from S. solfataricu

    Adiponectin levels are reduced in children born small for gestational age and are inversely related to postnatal catch-up growth

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    Adiponectin is an adipocytokine with insulin-sensitizing and antiatherogenic properties. Reduced concentrations of adiponectin precede the onset of type 2 diabetes and the development of atherosclerosis. Our aim was to quantify adiponectin concentrations in small for gestational age (SGA) children. Fifty-one SGA children, 24 obese, and 17 short-normal children with birth weight appropriate for gestational age (short-AGA) were studied. The statures of the SGA children were corrected for their midparental height and subdivided into two groups according to their corrected height: catch-up growth group, children with corrected height of 0 z-score or greater (n = 17); and noncatch-up growth group, subjects with corrected height less than 0 z-score (n = 34). SGA children showed adiponectin levels significantly lower than short-normal children (35.2 +/- 3.5 vs. 80.4 +/- 26.6 mug/ml; P < 0.0001) and obese children (77.5 +/- 39.4 ÎĽg/ml; P < 0.0001). Catch-up growth children showed adiponectin levels significantly lower than noncatch-up growth subjects (29.4 +/- 10.3 vs. 38.1 +/- 11.5 mug/ml; P = 0.01). Adiponectin concentrations were inversely related to height z-score, corrected stature, weight, and body mass index and were positively related to birth weight. Our results suggest that adiponectin levels are reduced in SGA children and are even lower in those with postnatal catch-up growth. Whether this finding implies a higher risk of developing type 2 diabetes and atherosclerosis remains to be established

    Spitzer Warm Mission Transition and Operations

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    Following the successful dynamic planning and implementation of IRAC Warm Instrument Characterization activities, transition to Spitzer Warm Mission operations has gone smoothly. Operation teams procedures and processes required minimal adaptation and the overall composition of the Mission Operation System retained the same functionality it had during the Cryogenic Mission. While the warm mission scheduling has been simplified because all observations are now being made with a single instrument, several other differences have increased the complexity. The bulk of the observations executed to date have been from ten large Exploration Science programs that, combined, have more complex constraints, more observing requests, and more exo-planet observations with durations of up to 145 hours. Communication with the observatory is also becoming more challenging as the Spitzer DSN antenna allocations have been reduced from two tracking passes per day to a single pass impacting both uplink and downlink activities. While IRAC is now operating with only two channels, the data collection rate is roughly 60% of the four-channel rate leaving a somewhat higher average volume collected between the less frequent passes. Also, the maximum downlink data rate is decreasing as the distance to Spitzer increases requiring longer passes. Nevertheless, with well over 90% of the time spent on science observations, efficiency has equaled or exceeded that achieved during the cryogenic mission

    The role of the multidisciplinary evaluation of interstitial lung diseases: Systematic literature review of the current evidence and future perspectives

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    The opportunity of a multidisciplinary evaluation for the diagnosis of interstitial pneumonias highlighted a major change in the diagnostic approach to diffuse lung disease. The new American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Society guidelines for the diagnosis of idiopathic pulmonary fibrosis have reinforced this assumption and have underlined that the exclusion of connective tissue disease related lung involvement is mandatory, with obvious clinical and therapeutic impact. The multidisciplinary team discussion consists in amoment of interaction among the radiologist, pathologist and pulmonologist, also including the rheumatologist when considered necessary, to improve diagnostic agreement and optimize the definition of those cases in which pulmonary involvement may represent the first or prominent manifestation of an autoimmune systemic disease. Moreover, the proposal of classification criteria for interstitial lung disease with autoimmune features (IPAF) represents an effort to define lung involvement in clinically undefined autoimmune conditions. The complexity of autoimmune diseases, and in particular the lack of classification criteria defined for pathologies such as anti-synthetase syndrome, makes the involvement of the rheumatologist essential for the correct interpretation of the autoimmune element and for the application of classification criteria, that could replace clinical pictures initially interpreted as IPAF in defined autoimmune disease, minimizing the risk of misdiagnosis. The aim of this review was to evaluate the available evidence about the efficiency and efficacy of different multidisciplinary team approaches, in order to standardize the professional figures and the core set procedures that should be necessary for a correct approach in diagnosing patients with interstitial lung disease

    Current Practice of Imaging-Guided Interventional Procedures in Rheumatic and Musculoskeletal Diseases: Results of a Multinational Multidisciplinary Survey

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    Objectives: To investigate opinion and routine practice of specialists from different disciplines on imaging techniques for interventional procedures related to rheumatic and musculoskeletal diseases (RMDs). Methods: An English-language questionnaire was developed by an international working group and distributed to health care providers of various disciplines involved in the care of people with RMDs via an online survey tool (SoSci Survey®) from December 2019 to May 2020. Results: A total of 1,105 respondents from 56 countries completed the survey, over 60% of participants were rheumatologists. The majority of respondents (88%) performed interventional procedures in RMDs patients and 90% of them used imaging guidance. Ultrasonography was the most frequently used technique, particularly among rheumatologists. X-ray and computed tomography were mainly used by radiologists. A discrepancy emerged between the importance assigned to certain items such as the availability of a second operator and their actual implementation in clinical practice. Local barriers, lack of resources and facilities were mentioned as the most relevant obstacles in this regard. Lack of training on imaging and/or imaging guided procedures did not emerge as a barrier to perform such interventions; in fact, 19% of respondents performing the procedures indicated not to have received adequate training in this field. Conclusions: This is the first multinational multidisciplinary survey exploring in detail the opinions and practice on imaging guidance for interventional procedures in RMDs. A harmonization of protocols based on international guidelines, along with adequate training programmes and interventions on barriers at national/local levels are the main unmet needs requiring attention
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