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Recombinase-aided polymerase chain reaction (RAP) is a sensitive, single-tube, two-stage nucleic acid amplification method. This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus (SA), Pseudomonas aeruginosa (PA), and Acinetobacter baumannii (AB) in the bloodstream based on recombinant human mannan-binding lectin protein (M1 protein)-conjugated magnetic bead (M1 bead) enrichment of pathogens combined with RAP. Recombinant plasmids were used to evaluate the assay sensitivity. Common blood influenza bacteria were used for the specific detection. Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR (M-RAP) and quantitative PCR (qPCR) assays. Kappa analysis was used to evaluate the consistency between the two assays. The M-RAP method had sensitivity rates of 1, 10, and 1 copies/μL for the detection of SA, PA, and AB plasmids, respectively, without cross-reaction to other bacterial species. The M-RAP assay obtained results for < 10 CFU/mL pathogens in the blood within 4 h, with higher sensitivity than qPCR. M-RAP and qPCR for SA, PA, and AB yielded Kappa values of 0.839, 0.815, and 0.856, respectively (P < 0.05). An M-RAP assay for SA, PA, and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia. [ABSTRACT FROM AUTHOR]

Acanthamoeba castellanii , a free-living amoeba, can be pathogenic to humans causing a corneal infection named Acanthamoeba keratitis (AK). The mannose-binding protein (MBP) is well established as the major factor related to Acanthamoeba pathogenesis. However, additional factors that participate in the adhesion process and protect trophozoites from cytolytic effects caused by host immune responses remain unknown. Ectonucleotidases, including 3′-nucleotidase/nuclease (3′-NT/NU), a bifunctional enzyme that was recently reported in A. castellanii , are frequently related to the establishment of parasitic infections. We verified that trophozoites can hydrolyze 3′-AMP, and this activity is similar to that observed in other protists. The addition of 3′-AMP increases the adhesion of trophozoites to LLC-MK2 epithelial cells, and this stimulation is completely reversed by DTT, an inhibitor of ecto-3′-nucleotidase activity. Lesions in corneal cells caused by AK infection may elevate the extracellular level of 3′-AMP. We believe that ecto-3′-nucleotidase activity can modulate the host immune response, thus facilitating the establishment of parasitic infection. This activity results from the generation of extracellular adenosine, which can bind to purinergic receptors present in host immune cells. Positive feedback may occur in this cascade of events once the ecto-3′-nucleotidase activity of trophozoites is increased by the adhesion of trophozoites to LLC-MK2 cells. [ABSTRACT FROM AUTHOR]

Objectives Proteomics principles and techniques were used to detect and screen out the expression of differential proteins in urine of athletes after exercise with different intensities; the changes of urinary protein components and the correlations among the changes, human immune function and exercise fatigue were investigated, which provided scientific basis and practical methods for exercise biochemical monitoring. Methods Based on Two-dimensional electrophoresis (2-DE), differential expression of urine proteome of 8 male athletes was analyzed after exercises of 55%, 75%, 85% and 95% VO2max intensity, respectively; the protein expressed levels which were up-regulated by at least 5-fold and with repeatability were screened and analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results A total of 275 differentially expressed protein points was detected after different exercise intensities, down-regulated protein points were 85 and up-regulated 190. After screening expressed levels which were up-regulated by at least 5-fold protein, a total of 29 protein was identified, showing a close relation to the biological processes of immune regulation and inflammatory response. Conclusions Proteomics better explains what happens to the urine proteome after different exercises, among which, apolipoprotein and zinc-a2-glycoprotein are related to lipid metabolism after exercise; immunoglobulin, albumin, complement component C3, mannose-binding lectin protein 19 and Vitamin D binding protein are related to immune regulation. The theoretical basis and application method are provided for the evaluation of the effects of exercise training on human immune function and fatigue. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common form of dementia, characterized by the accumulation of β‐amyloid plaques and the formation of neurofibrillary tangles. Extracellular vesicles (EVs) are small vesicles surrounded by a lipid bilayer membrane, which may be involved in the progression of AD. Glycans are essential building blocks of EVs, and we hypothesized that EV glycans may reflect pathological conditions of various diseases. Here, we performed glycan profiling of EVs prepared from sera of three AD patients (APs) compared to three healthy donors (HDs) using lectin microarray. Distinct glycan profiles were observed. Mannose‐binding lectins exhibited significantly higher signals for AP‐derived EVs than HD‐derived EVs. Lectin blotting using mannose‐binding lectin (rPALa) showed a single protein band at ~ 80 kDa exclusively in AP‐derived EVs. LC‐MS/MS analysis identified a protein band precipitated by rPALa as CD61, a marker of platelet‐derived exosomes (P‐Exo). Sandwich assays using Tim4 with specificity for phosphatidylserine on EVs and antibodies against P‐Exo markers (CD61, CD41, CD63, and CD9) revealed that P‐Exo is significantly elevated in sera of APs (n = 16) relative to age‐ and sex‐matched HDs (n = 16). Tim4‐αCD63 showed the highest value for the area under the curve (0.957) for discriminating APs from HDs, which should lead to a better understanding of AD pathology and may facilitate the development of a novel diagnostic method for AD. [ABSTRACT FROM AUTHOR]

This study compared piezoelectric (PE) and conventional drills (CD) for maxillary aesthetic zone implant insertion. This was a prospective split-mouth study. Implants were divided into two groups. Beds were prepared with CDs in group I and PE in group II. The implant stability quotient (ISQ) of the mechanical implant stability (MIS) was measured intraoperatively. The ISQ of the biological implant stability (BIS) was recorded at postoperative second and fourth months. Marginal bone loss (MBL) and bone density (BMD) were measured in the first and second years after prosthetic loading. The osteotomy time was also documented for both techniques. P values <0.05 were considered significant. Sixty implants in 30 patients were included. PE provided a significantly higher ISQ. All values were above 70 throughout the follow-up period. The mean of the ISQ for MIS was 63.78 ± 1.03 and 73.89 ± 1.05 in group I and group II, respectively (p = 0.003). PE needed significantly longer osteotomy time with a mean of 11.99 ± 0.839 min. The BIS quality had high stability in group II and medium stability in group I throughout the study period. Its values decreased in both groups. Group II had a lesser percentage of decrease. However, it was significant only at time intervals between intraoperative and two months' postoperative (p = 0.004). MBL and BMD demonstrated insignificant results. The implant site preparation with PE devices should be preferred to CDs whenever possible, because they seem to enhance implant stability and osseointegration, especially at the initial stages of healing. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the influence of different loading protocols on marginal bone loss (MBL). The outcomes of different implant loading protocols were assessed at 1 year after implantation, with focus on MBL; protocols included immediate, immediate non-occlusal, early, and conventional loading. The search strategy resulted in 889 studies. Twenty-two of these studies fulfilled the inclusion criteria. Among the included studies, the lowest MBL was for immediately loaded implants (0.05 ± 0.67 mm) and the highest for immediate non-occlusally loaded implants (1.37 ± 0.5 mm). The results of the meta-analysis showed an estimated mean MBL of 0.457 mm (95% confidence interval (CI) 0.133–0.781) for immediate loading, 0.390 mm (95% CI 0.240–0.540) for immediate non-occlusal loading, 0.488 mm (95% CI 0.289–0.687) for early loading (>2 days to <3 months), and 0.852 mm (95% CI 0.429–1.275) for conventional loading (>3 months) implant protocols. The lowest decrease in 1-year implant survival per millimetre increase in MBL was observed for immediate loading and the highest for conventional loading. Conventional loading showed a significantly higher MBL than the other three loading protocols. This systematic review and meta-analysis indicates that the immediate loading protocol is a reasonable alternative to the conventional loading protocol. [ABSTRACT FROM AUTHOR]

The present paper studies two approaches to the expressiveness of propositional modal logics based on first-degree entailment logic, FDE. We first consider the basic FDE-based modal logic BK and certain systems in its vicinity, and then turn to some FDE-based modal logics in a richer vocabulary, including modal bilattice logic, MBL. On the one hand, modeltheoretic proofs of the definability of connectives along the lines of [7] and [17] are given for various FDE-based modal logics. On the other hand, building on [10], expressibility is considered in terms of mutual faithful embeddability of one logic into another logic. A distinction is drawn between definitional equivalence, which is defined with respect to a pair of structural translations between two languages, and weak definitional equivalence, which is defined with respect to a weaker notion of translations. Moreover, the definitional equivalence of some FDE-based modal logics is proven, especially the definitional equivalence of MBL and a conservative extension of the logic BK2 ×BK2, which underlines the central role played by BK among FDE-based modal logics. [ABSTRACT FROM AUTHOR]

The quality of the bone plays an important part in marginal bone loss (MBL) around dental implants. The aim of this study was to compare MBL around implants the sockets of which had been preserved with the bone around healed sites in the mandible after extraction of first molars. It was a prospective, cohort study in which subjects were divided into three groups (n = 30 in each): dental implants were placed six months after preservation of the socket in the first group, eight weeks after tooth extraction in the second, and six months after tooth extraction in the third. The changes between the marginal bone level after loading of the implant and 12, 24, and 36 months later were considered to be the MBL. Age and sex were the variables studied, the condition of the bone (healed socket or preservation) was a predictive factor, and MBL was the outcome. Analysis of variance was used to compare MBL and age among groups. There were no differences in the mean MBL among the three groups 12, 24, and 36 months after loading (p = 0.55, p = 0.22, p = 0.38, respectively). Preservation of the socket did not seem to affect MBL of the first molar of the mandible. [ABSTRACT FROM AUTHOR]

• A. castellanii trophozoites have an acid ecto-phosphatase activity; • Sodium orthovanadate inhibits both the ecto-phosphatase activity and the adhesion of trophozoites to epithelial cells. • The incubation with mannose was able to stimulate ecto-phosphatase activity; Acanthamoeba castellanii is a free-living amoeba and an opportunistic pathogen for humans that can cause encephalitis and, more commonly, Acanthamoeba keratitis. During its life cycle, A. castellanii may present as proliferative and infective trophozoites or resistant cysts. The adhesion of trophozoites to host cells is a key first step in the pathogenesis of infection. A major virulence protein of Acanthamoeba is a mannose-binding protein (MBP) that mediates the adhesion of amoebae to cell surfaces. Ectophosphatases are ecto-enzymes that can dephosphorylate extracellular substrates and have already been described in several microorganisms. Regarding their physiological roles, there is consistent evidence that ectophosphatase activities play an important role in parasite-host interactions. In the present work, we identified and biochemically characterized the ectophosphatase activity of A. castellanii. The ectophosphatase activity is acidic, stimulated by magnesium, cobalt and nickel, and presents the following apparent kinetic parameters: K m = 2.12 ± 0.54 mM p -NPP and V max = 26.12 ± 2.53 nmol p -NP × h−1 × 10-6 cells. We observed that sodium orthovanadate, ammonium molybdate, sodium fluoride, and inorganic phosphate are able to inhibit ectophosphatase activity. Comparing the two stages of the A. castellanii lifecycle, ectophosphatase activity is significantly higher in trophozoites than in cysts. The ectophosphatase activity is stimulated by mannose residues and is significantly increased when trophozoites interact with LLC-MK2 cells. The inhibition of ectophosphatase by pretreatment with sodium orthovanadate also inhibits the adhesion of trophozoites to epithelial cells. These results allow us to conclude that the ectophosphatase activity of A. castellanii is somehow important for the adhesion of trophozoites to their host cells. According to our data, we believe that the activation of MBP by mannose residues triggers the stimulation of ectophosphatase activity to facilitate the adhesion process. [ABSTRACT FROM AUTHOR]

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The pattern recognition molecules (PRMs) able to activate complement via the lectin pathway are suspected to be involved in the interaction between pathogenic Mycobacteria and the host immune response. Recently, we have found strong interactions between 25 and 35 kDa mycobacterial cell fractions and mannose-binding lectin (MBL) and ficolins. Here we demonstrate that two biologically important mycobacterial structures, mannosylated lipoarabinomannan (ManLAM) and the antigen 85 (Ag85) complex, induce activation of the lectin pathway of complement. The strong interaction of recombinant MBL with purified ManLAM was confirmed, but no binding of recombinant ficolins (ficolin-1, -2, -3) with this structure was observed. Interestingly, all PRMs tested reacted with the mycobacterial antigen 85 (Ag85) complex. Based on the use of specific inhibitors (mannan for MBL, acetylated bovine serum albumin for ficolin-1 and -2, Hafnia alvei PCM 1200 lipopolysaccharide for ficolin-3), we concluded that carbohydrate-recognition (MBL) and fibrinogen-like domains (ficolins) were involved in these interactions. Our results indicate that the mycobacterial antigen 85 complex is a target for ficolins and MBL. Furthermore, those PRMs also bound to fibronectin and therefore might influence the Ag85 complex-dependent interaction of Mycobacterium with the extracellular matrix. [ABSTRACT FROM AUTHOR]

The lipopolysaccharide (LPS) is involved in the interaction between Gram-negative pathogenic bacteria and host. Mannose-binding lectin (MBL), complement-activating soluble pattern-recognition receptor targets microbial glycoconjugates, including LPS. We studied its interactions with a set of Yersinia enterocolitica O:3 LPS mutants. The wild-type strain LPS consists of lipid A (LA) substituted with an inner core oligosaccharide (IC) which in turn is substituted either with the O-specific polysaccharide (OPS) or the outer core hexasaccharide (OC), and sometimes also with the enterobacterial common antigen (ECA). The LPS mutants produced truncated LPS, missing OPS, OC or both, or, in addition, different IC constituents or ECA. MBL bound to LA-IC, LA-IC-OPS and LA-IC-ECA but not LA-IC-OC structures. Moreover, LA-IC substitution with both OPS and ECA prevented the lectin binding. Sequential truncation of the IC heptoses demonstrated that the MBL targets the IC heptose region. Furthermore, microbial growth temperature influenced MBL binding; binding was stronger to bacteria grown at room temperature (22 °C) than to bacteria grown at 37 °C. In conclusion, our results demonstrate that MBL can interact with Y. enterocolitica LPS, however, the in vivo significance of that interaction remains to be elucidated. [ABSTRACT FROM AUTHOR]

The article discusses research which evaluates the manno-oligosaccharide-binding ability of mouse ReglV/GST-fusion protein by complex formation with the carbohydrate-containing polyamidoamine dendrimer (PD). It noted that GST-mReglV showed affinity for mannan- and manno-oligosaccharide containing PD. It informs that binding was inhibited by manno-oligosaccharides but not by mannose which reveals extended structure of binding site in contrast with carbohydrate-binding protein lectins.

Summary: Background: Mannose-binding lectin (MBL) is a key component of innate immunity. MBL deficiency is common (10–30% of the general population depending on the definition used) and has been associated with disease progression in cystic fibrosis. We aimed to assess the effect of MBL deficiency on disease severity in non-cystic fibrosis bronchiectasis. Methods: We recruited patients with non-cystic fibrosis bronchiectasis and age-matched and sex-matched controls at a specialist bronchiectasis clinic in Edinburgh, UK. We assessed MBL function with genotyping (low-expressing genotype [deficiency] defined as homozygosity for exon 1 mutations [YO/YO] or compound heterozygosity [XA/YO]; YA/YO and XA/XA genotypes were defined as intermediate-expressing with all other genotypes defined as high-expressing) and serum measurements (deficiency defined with two parameters: <500 ng/mL or <200 ng/mL). We assessed rates of exacerbation, chronic bacterial colonisation, and lung function during 4 years of follow-up. Findings: We included 470 patients with bronchiectasis and 414 controls. MBL genotype frequencies and MBL serum concentrations did not differ between patients and controls. 55 (12%) patients with bronchiectasis had low-expressing genotypes. These patients had a mean of 2·7 exacerbations per year (SD 1·8), compared with 1·9 per year (1·2) for 135 patients with intermediate-expressing genotypes and 1·9 per year (1·3) for 280 patients with high-expressing genotypes (p<0·0001). Chronic colonisation with bacteria was most frequent in patients with low-expressing genotypes (47 [85%] patients vs 82 [61%] patients with intermediate-expressing genotypes and 183 [65%] patients with high-expressing genotypes; p=0·0041); especially P aeruginosa colonisation (19 [35%] patients vs 13 [10%] patients and 36 [13%] patients; p<0·0001). Patients with low-expressing genotypes were more likely to be admitted to hospital for severe exacerbations during follow-up (27 [49%] patients vs 42 [31%] patients and 87 [31%] patients; p=0·032). Patients with low-expressing genotypes also had increased scores for radiological severity and worse quality of life compared with the other two groups. MBL serum deficiency (<200 ng/mL) was associated with increased exacerbations, hospital admissions, and radiological severity. When <500 ng/mL was used as the definition of deficiency, the associations with exacerbation frequency and radiological severity were no longer significant. Interpretation: MBL might be an important modifier of disease severity in non-CF bronchiectasis. Funding: UK Medical Research Council, UK Chief Scientists Office. [ABSTRACT FROM AUTHOR]

Abstract: Non-union of a fracture is a phenomenon that may complicate bone healing. Consolidation of a fracture can be divided into three phases: inflammation, reconstruction, and remodeling. Both the complement system and the coagulation cascade interact at various steps throughout these phases. Several complement components are specifically associated with the inflammation phase of bone healing. However, in which way complement components influence the remodeling phase has not been established yet. Mannose-Binding Lectin (MBL) and its associated serine protease MASP-2 (Mannanbinding lectin serine protease-2) are important initiating proteins of the complement system and have also been implicated in coagulation. With respect to the characteristics and interactions of MBL, it is likely to assume a considerable influence of MBL in the remodeling phase of bone healing. A deficiency in MBL then, caused by a genetic variation, may disturb this particular process during bone healing, due to either an accumulation of apoptotic cells or to a diminished scaffold of fibrin molecules. The next step would be early identification of patients with a deficiency of MBL, allowing for early therapeutic intervention or even non-union preventive measures. This review aims to discuss the true and hypothesized role of MBL in bone healing and the consequences of a depletion of the protein in the etiology of fracture non-union. [Copyright &y& Elsevier]

Abstract: Background: Mannose-binding lectin (MBL) is a pattern-recognition molecule of the innate immune system and may be involved in the pathogenesis of inflammatory bowel disease (IBD). Our aim was to assess the prevalence of MBL deficiency in a cohort of patients with paediatric-onset IBD and study whether it is associated with the clinical manifestations, serum antibody formation, or genetic factors. Methods: This prospective study included 159 paediatric patients (mean age: 14.0years) with IBD [107 patients with Crohn disease (CD) and 52 patients with ulcerative colitis (UC)]. Furthermore, 95 controls were investigated. Serum samples were determined for MBL by enzyme-linked immunosorbent assay (ELISA) and for serologic markers [autoantibodies against Saccharomyces cerevisiae (ASCA) and perinuclear components of neutrophils (pANCA)] by indirect immunofluorescent assay. NOD2/CARD15 variants were tested by polymerase chain reaction/restriction fragment length polymorphism. Results: The MBL serum concentration was significantly lower in IBD patients(both with CD and UC) compared to controls (IBD, p=0.007, CD, p=0.04, UC p=0.004). Prevalence of low MBL level (<500ng/mL) was significantly higher in both CD and UC groups compared to controls (p=0.002 and p=0.006). Furthermore, low MBL level was associated with isolated ileal involvement (p=0.01) and MBL deficiency (<100ng/mL) with male gender (p=0.004) in patients with CD. We failed to confirm any correlation between MBL deficiency and serum autoantibodies or NOD2/CARD15 variants. Conclusions: Our results suggest that low MBL associated with paediatric-onset IBD and ileal CD may be considered an additional marker of the IBD pathogenesis. [Copyright &y& Elsevier]

To review the scientific evidence regarding the marginal bone loss around the tissue-level and bone-level implants. MEDLINE-PubMed and EMBASE databases were searched for the relevant English articles (up to February 2019) assessing the marginal bone loss (MBL) as the primary outcome. To be selected, studies were supposed to directly mention "tissue-level" and "bone-level" implants or implants with and without a smooth neck. Relevant data were extracted and meta-analysis was performed to evaluate the effect of implant neck design. A total of 19 studies (10 clinical, and 9 RCT studies) were included for qualitative analysis. There was a vast heterogeneity between studies in terms of implant designs and study protocol. Out of 19 articles included, 11 studies reached to a statistically significant difference in MBL between the groups; however, the differences were not found to be clinically relevant. Bone-level implants with platform-switched abutments in most of the cases showed better marginal bone stability compared to tissue-level implants or bone-level implants with matching abutments. Seven RCTs with 12 months follow-up data were selected for meta-analysis (I 2 = 93%; heterogeneous), and the results showed less MBL around bone-level implants compared to tissue-level group (WMD = −0.21 mm; 95% CI −0.42, 0.00; P = 0.06). The available data regarding comparison of MBL around bone-level and tissue-level implants are heterogeneous. Bone-level implants with platform switching may better preserve crestal bone. [ABSTRACT FROM AUTHOR]

The anatomy of soft tissues around dental implants is extremely important to prevent inflammatory periimplant diseases and ensure healthy, stable and long-term survival of a dental implant. Various methods and materials for increasing the physiological thickness of tissues have been described including connective tissue graft (CTG) and xenogenic collagen matrix (XCM). While assessing various materials it is necessary to establish objective measurement method to determine the minimum amount of tissue thickness to maintain a stable level of bone around the implant. The aim of the study was to determine the effect of soft tissues in the implant area on the marginal bone level in the implant area and to define of the critical gingival thickness to minimize marginal bone level (MBL) loss. 75 bone level implants (Conelog® Camlog, Switzerland) were inserted in the aesthetic area. Thickening of soft tissues was performed using CTG and XCM. 12 months after the loading with final restoration, the thickness of soft tissues in the implant area was examined with ultrasound USG device (Pirop®, Echoson, Poland), and each implant was subjected to RVG examination, where MBL loss was determined. A tendency to occur less MBL loss was found when thicker gingiva was present. The higher soft tissue thickness was, the lower MBL loss has occurred. A critical value for tissue thickness was determined as TKT ≤ 2.88. In case of thin biotype soft tissue augmentation is required when value of tissue thickness in ultrasound measure is less than 2.88 mm. [ABSTRACT FROM AUTHOR]