Improved serological detection of rheumatoid arthritis: a highly antigenic mimotope of carbonic anhydrase III selected in a murine model by phage display

IntroductionRheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that affects around 1 % of the human population worldwide. RA diagnosis can be difficult as there is no definitive test for its detection. Therefore, the aim of this study was to identify biomarkers that could be used for RA diagnosis.MethodsSera from a collagen-induced arthritis mouse model were used to select potential biomarkers for RA diagnosis by phage display technology. In silico and in vitro analyses were performed to characterize and validate the selected peptides. Samples were classified into three groups: RA; two other immune-mediated rheumatic diseases (systemic lupus erythematosus (SLE) and ankylosing spondylitis (AS)); and healthy controls (HC). Enzyme-linked immunosorbent assay (ELISA) was carried out to determine antibody levels, and diagnostic parameters were determined by constructing receiver operating characteristic curves. Mass spectrometry and Western blot were performed to identify the putative autoantigen that was mimicked by a highly reactive mimotope.ResultsAfter three rounds of selection, 14 clones were obtained and tested for immunoreactivity analysis against sera from RA and HC groups. The phage-fused peptide with the highest immunoreactivity (M12) was synthesized, and was able to efficiently discriminate RA patients from SLE, AS and HCs (p < 0.0001) by ELISA. The specificity and sensitivity of anti-M12 antibodies for RA diagnosis were 91 % and 84.3 %, respectively. The M12 peptide was identified as one that mimics a predicted antigenic site of the carbonic anhydrase III (CAIII) protein, a ubiquitous biomarker that has been identified in patients with other diseases.ConclusionM12 is the first peptide associated with the CAIII protein that may be used as an antigen for antibody detection to aid in RA diagnosis with high sensitivity and specificity.     

Liposomal-based lidocaine formulation for the improvement of infiltrative buccal anaesthesia

This study describes the encapsulation of the local anaesthetic lidocaine (LDC) in large unilamellar liposomes (LUV) prepared in a scalable procedure, with hydrogenated soybean phosphatidylcholine, cholesterol and mannitol. Structural properties of the liposomes were assessed by dynamic light scattering, nanoparticle tracking analysis and transmission electron microscopy. A modified, two-compartment Franz-cell system was used to evaluate the release kinetics of LDC from the liposomes. The in vivo anaesthetic effect of liposomal LDC 2% (LUV_LDC) was compared to LDC 2% solution without (LDC_PLAIN) or with the vasoconstrictor epinephrine (1:100 000) (LDC_VASO), in rat infraorbital nerve blockade model. The structural characterization revealed liposomes with spherical shape, average size distribution of 250?nm and low polydispersity even after LDC incorporation. Zeta potential laid around –30?mV and the number of suspended liposomal particles was in the range of 10¹² vesicles/mL. Also the addition of cryoprotectant (mannitol) did not provoke structural changes in liposomes properties. In vitro release profile of LDC from LUV fits well with a biexponential model, in which the LDC encapsulated (EE%?=?24%) was responsible for an increase of 67% in the release time in relation to LDC_PLAIN (p?<?0.05). Also, the liposomal formulation prolonged the sensorial nervous blockade duration (～70?min), in comparison with LDC_PLAIN (45?min), but less than LDC_VASO (130?min). In this context, this study showed that the liposomal formulations prepared by scalable procedure were suitable to promote longer and safer buccal anaesthesia, avoiding side effects of the use of vasoconstrictors.     

Management of intraoral stents for radiotherapy during COVID-19 pandemic

Radiotherapy is being performed in many situations as a curative approach for head and neck cancer instead of surgery due to the current novel coronavirus disease (COVID-19) pandemic. A recent publication reported that even hypofractionation was being conducted in order to reduce the daily exposure of both patients and the medical staff involved in cancer therapies. As a result, dental teams may be requested more frequently than usual to fabricate intraoral stents (IOS). Given that IOS may be a potential source of COVID-19 contagion, the main purpose of the present correspondence is to offer a guide on how health professionals may be safely presented in the room, on the management of the IOS and also how to sanitize the stents.     

Growth and respiration of two pleuronectiform juveniles from a western Mediterranean bay

Growth and respiration of juveniles of two pleuronectiforms ( Buglossidium luteum and Arnoglossus thori ) were studied. The first species has a single period of benthic recruitment (April), a growth pause in winter, and a very low winter metabolism (at 11°C). The second species has two peaks of recruitment (May–June and September–October), an exponential growth with no significant pause in winter, and little reduction of metabolism at 11°C.
Such differences are important factors allowing the sharing of the same biotope by these small benthic predators.     

Adherens junctions determine the apical position of the midbody during follicular epithelial cell division

Cytokinesis is asymmetric along the apical–basal axis of epithelial cells, positioning the midbody near the apical domain. However, little is known about the mechanism and purpose of this asymmetry. We use live imaging of Drosophila follicle cell division to show that asymmetric cytokinesis does not result from intrinsic polarization of the main contractile ring components. We show that adherens junctions (AJs) maintain close contact with the apical side of the contractile ring during cytokinesis. Asymmetric distribution of AJ components within follicle cells and in the otherwise unpolarized S2 cells is sufficient to recruit the midbody, revealing that asymmetric cytokinesis is determined by apical AJs in the epithelia. We further show that ectopic midbody localization induces epithelial invaginations, shifting the position of the apical interface between daughter cells relative to the AB axis of the tissue. Thus, apical midbody localization is essential to maintain epithelial tissue architecture during proliferation.     

Rapid and sensitive detection of Citrus Bacterial Canker by loop-mediated isothermal amplification combined with simple visual evaluation methods

Background  

Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is Xanthomonas citri subsp. citri, while Xanthomonas fuscans subsp. aurantifolii, strain B causes type B CBC and Xanthomonas fuscans subsp. aurantifolii strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment.     

Yeast diversity in a mesotrophic lake on the karstic plateau of Lagoa Santa,MG-Brazil

The yeast diversity in a paleo-karstic lake of the Lagoa Santa plateau was studied during March 1986–March 1987. Water samples were collected monthly at five stations and the yeasts were isolated at 25 °C on Sabourad dextrose agar supplemented with 0.5% of yeast extract and 10 mg% of chloramphenicol. August and February showed the highest numbers of isolates, coinciding, respectively with the beginning and the ending of stratification. Of 56 isolated species, Aureobasidium pullulans, Candida famata, Cryptococcus albidus, Cryptococcus laurentii, Rhodotorula glutinis, Rhodotorula rubra and Trichosporon cutaneum occurred at the highest frequencies. A. pullulans showed greatest prevalence during the dry period (winter), whereas C. famata, Cr. albidus, Cr. laurentii and Rh. rubra were prevalent during the rainy season (summer). Tr. cutaneum was distributed between July and November. Most isolates yeasts are associated with plants and soils, and are important in decomposition of aquatic macrophytes. Furthermore, a possible role of these species as indicators of pollution is discussed.