Application of a dot blot hybridization assay for genotyping Streptococcus uberis from Brazilian dairy herds

Streptococcus uberis is a major cause of environmental mastitis in many regions, and it is associated with clinical and subclinical infections. Although the main source of infection is the environment, reports of strains with a contagious profile have been described. Dot blot hybridization analysis allows the rapid identification of S. uberis population structures within and between herds, and it helps to identify strain diversity as well as possible clonal lineages that directly affect the control of bovine mastitis caused by this pathogen. The aim of this study was to evaluate the diversity of S. uberis isolates obtained from clinical (n = 22) and subclinical (n = 22) cases of mastitis in dairy herds (n = 13) in Brazil over a period of 12 mo. We submitted 44 S. uberis isolates to dot blot hybridization followed by automatic data analysis. We identified 8 different hybridization patterns using genetic markers associated with virulence factors and taxonomy, indicating diversity of S. uberis within the population and suggesting environmental transmission. However, the evidence of identical dot blot patterns in different mammary quarters from the same animal also suggested local contagious transmission. Of the virulence genes evaluated, we found a high prevalence of the genes sua, pauA, and gapC, highlighting the importance of these virulence factors for the adhesion, invasion, and multiplication of S. uberis in subclinical and clinical intramammary infections.

Comparative proteomic analysis of dental cementum from deciduous and permanent teeth

BACKGROUND AND OBJECTIVES

Dental cementum (DC) is a mineralized tissue covering tooth roots that plays a critical role in dental attachment. Differences in deciduous vs. permanent tooth DC have not been explored. We hypothesized that proteomic analysis of DC matrix would identify compositional differences in deciduous (DecDC) vs. permanent (PermDC) cementum that might reflect physiological or pathological differences, such as root resorption that is physiological in deciduous teeth but can be pathological in the permanent dentition.

METHODS

Protein extracts from deciduous (n = 25) and permanent (n = 12) teeth were pooled (five pools of DecDC, five teeth each; four pools of PermDC, three teeth each). Samples were denatured, and proteins were extracted, reduced, alkylated, digested, and analyzed by liquid chromatography-mass spectrometry (LC-MS/MS). The beta-binomial statistical test was applied to normalized spectrum counts with 5% significance level to determine differentially expressed proteins. Immunohistochemistry was used to validate selected proteins.

RESULTS

A total of 510 proteins were identified: 123 (24.1%) exclusive to DecDC; 128 (25.1%) exclusive to PermDC; 259 (50.8%) commonly expressed in both DecDC and PermDC. Out of 60 differentially expressed proteins, 17 (28.3%) were detected in DecDC, including myeloperoxidase (MPO), whereas 43 (71.7%) were detected in PermDC, including decorin (DCN) and osteocalcin (BGLAP). Overall, Gene Ontology (GO) analysis indicated that all expressed proteins were related to GO biological processes that included localization and response to stress, and the GO molecular function of differentially expressed proteins was enriched in cell adhesion, molecular binding, cytoskeletal protein binding, structural molecular activity, and macromolecular complex binding. Immunohistochemistry confirmed the trends for selected differentially expressed proteins in human teeth.

CONCLUSIONS

Clear differences were found between the proteomes of DecDC and PermDC. These findings may lead to new insights into developmental differences between DecDC and PermDC, as well as to a better understanding of physiological/pathological events such as root resorption.

A novel de novo heterozygous ALPL nonsense mutation associated with adult hypophosphatasia

Using genetic, clinical, biochemical, and radiographic assessment and bioinformatic approaches, we present an unusual case of adult HPP caused by a novel de novo heterozygous nonsense mutation in the alkaline phosphatase (ALPL).

INTRODUCTION

Hypophosphatasia (HPP) is caused by genetic alterations of the ALPL gene, encoding the tissue-nonspecific isozyme of alkaline phosphatase (TNSALP). Here, the purpose was to perform clinical and molecular investigation in a 36-year-old Caucasian woman suspected to present adult HPP.

METHODS

Medical and dental histories were obtained for the proposita and family members, including biochemical, radiographic, and dental assessments. ALPL mutational analysis was performed by the Sanger sequencing method, and the functional impact prediction of the identified mutations was assessed by bioinformatic methods.

RESULTS

We identified a novel heterozygous nonsense mutation in the ALPL gene (NM_000478.6:c.768G>A; W[TGG]>*[TGA]) associated with spontaneous vertebral fracture, severe back pain, musculoskeletal pain, low bone density, and short-rooted permanent teeth loss. Functional prediction analysis revealed that the Trp256Ter mutation led to a complete loss of TNSALP crown domain and extensive loss of other functional domains (calcium-binding domain, active site vicinity, and zinc-binding site) and over 60% loss of homodimer interface residues, suggesting that the mutant TNSALP molecules are nonfunctional and form unstable homodimers. Genotyping of the ALPL in the proposita's parents, sister, and niece revealed that in this case, HPP occurred due to a de novo mutation.

CONCLUSION

The present study describes a novel genotype-phenotype and structure-function relationship for HPP, contributing to a better molecular comprehension of HPP etiology and pathophysiology.

Spatial analysis of vaccination coverage in Paraíba in 2016

Introduction

Immunization is a human right, being considered an action of the most successful and cost-effective in public health. In Brazil, it is an action that is linked to primary health care, In Brazil, the National Immunization Program (PNI), created in 1973, is recognized as a world reference of public health policy, as it offers all vaccines recommended by the World Organization health care in its national vaccination calendar.

Objective

Spatial analysis of vaccination coverage of children aged 0 to 11 months in Paraíba in 2016.

Methods

Cross-sectional study, with information on doses applied to children under 1 year of age obtained at the PNI, by municipality of Paraíba. Live birth data from the Live Birth information system (SINASC). Descriptive analysis, chi-square test, spatial analysis.

Results

In Paraíba, 54.3% of the municipalities had adequate vaccination coverage, for BCG we have 68%, Hepatitis B (34.5%), Hib and DTP (35%), Polio (29.6%), pneumococcal (46.6%) and meningococcal (42.6%). The sertão paraibano is the mesoregion with the largest number of municipalities in the state with adequate vaccination coverage (p < 0.01), the paraiba forest is the region with the highest number of municipalities with very low coverage (p < 0.01).

Conclusions

Thus, Paraíba does not present a homogeneous vaccination coverage, not having 'herd immunity'. This fact leaves the state vulnerable to the return of immunopreventable diseases and thus at risk of raising infant morbidity and mortality, constituting an important public health problem.

Key messages

Immunization is a human right, being considered an action of the most successful and cost-effective in public health. Paraíba does not present a homogeneous vaccination coverage, not having 'herd immunity'.

Distribution of breast cancer and the relationship with contaminated areas in Brazil

Introduction

Breast cancer is a worldwide public health issue. The distribution of the disease presents different behavior depending on the region. In Brazil, for the triennium 2020/2022, approximately 66.28 per 100,000 new cases are expected each year, with the highest incidence in the southeast region 81.06 per 100,000. The region of this study has high mortality rates from the disease and several environmental contaminants classified as carcinogenic.

Methodology

A spatial and temporal ecological study of the breast cancer distribution in the municipalities of the Baixada Santista with secondary data from 2000 to 2011, in women 20 years or older. The cancer data of 3,233 cases were provided by the Oncocentro Foundation of São Paulo, of the contaminated areas were provided by the Technology of Environmental Sanitation Company, and the population at risk were provided by the State Data Analysis System. Standardized coefficients of annual breast cancer rates for each municipality, to characterize exposure, an indicator of contamination per municipality was constructed. Pearson's correlation was used to analyze breast cancer rates and environmental contamination rates. Cartographic sequencing to analyze the distribution and spatiotemporal evolution of outcome and exposure. Trend analysis used linear regression.

Results

The municipality of Santos presented the highest rates of the disease. Pearson's correlation was positive, with r = 0.7 (p = 0.036). Spatially, the most contaminated areas had the highest rates of breast cancer, except in one municipality. Trend analysis in eight of the nine municipalities in the region signaled an increased number of cases.

Conclusions

The study confirmed that environmental contamination interferes with the distribution of breast cancer and the temporal trend signaled an increase in the disease in eight of the nine municipalities in the region.

Key messages

Environmental Contamination. Breast Cancer.

Factors associated with high-risk pregnancy: role of environmental contaminants, Brazil

Introduction

The Região Metropolitana da Baixada Santista (RMBS) is considered as a region with the worst maternal and child mortality rates in the state of São Paulo, Brazil. Besides this, RMBS has the worst rates of environmental contamination. High-Risk Pregnancy is one of the factors that lead to a higher chance of morbidity and mortality of the mother and fetus binomial.

Objective

Evaluate the relationship between exposure to environmental contaminants and high-risk pregnancy.

Methodology

Case-control study, using a probabilistic sample composed of 402 pregnant women divided into with and without high-risk pregnancy. The instrument used was a self-administered questionnaire and secondary data on contaminated areas obtained from the Environmental Company of the State of São Paulo. Descriptive analysis, Chi-square test, univariate and multiple logistic regression analysis were performed. The participants were also georeferenced by place of residence.

Results

It was observed an association, by chi-square test between high-risk pregnancy and age over 35 years (p < 0.05), use of insecticide (p < 0.001), consumption of foods packed in plastics (p = 0.050) and manipulation with oil paint (p = 0.002). The final multiple logistic regression model demonstrated that those who live in contaminated areas are 2 times more likely to have a risk pregnancy (OR = 1.993; 95%CI: 1.02; 3.90), as well as identified as jointly important risk factors for pregnancy: working in health services (OR = 3.97 (95%CI: 1.00; 16.09)), use of insecticide (OR = 3.45 (95%CI: 1.66; 7.16)) and use of oil paint (OR = 6.96 (95%CI: 1.38; 35.09)).

Conclusions

Environmental contaminants play an important role in pregnancy, and mitigating measures are needed to improve the environment and reduce high-risk pregnancy in RMBS.

Key messages

Exposure to the environmental contaminants is an important rik factor in the pregnancy. The Região Metropolitana da Baixada Santista (RMBS) is considered as a region with the worst maternal and child mortality rates in the state of São Paulo, Brazil.

Novel LRAP-binding partner revealing the plasminogen activation system as a regulator of cementoblast differentiation and mineral nodule formation in vitro

Amelogenin isoforms, including full-length amelogenin (AMEL) and leucine-rich amelogenin peptide (LRAP), are major components of the enamel matrix, and are considered as signaling molecules in epithelial-mesenchymal interactions regulating tooth development and periodontal regeneration. Nevertheless, the molecular mechanisms involved are still poorly understood. The aim of the present study was to identify novel binding partners for amelogenin isoforms in the cementoblast (OCCM-30), using an affinity purification assay (GST pull-down) followed by mass spectrometry and immunoblotting. Protein-protein interaction analysis for AMEL and LRAP evidenced the plasminogen activation system (PAS) as a potential player regulating OCCM-30 response to amelogenin isoforms. For functional assays, PAS was either activated (plasmin) or inhibited (ε-aminocaproic acid [aminocaproic]) in OCCM-30 cells and the cell morphology, mineral nodule formation, and gene expression were assessed. PAS inhibition (EACA 100 mM) dramatically decreased mineral nodule formation and expression of OCCM-30 differentiation markers, including osteocalcin (Bglap), bone sialoprotein (Ibsp), osteopontin (Spp1), tissue-nonspecific alkaline phosphatase (Alpl) and collagen type I (Col1a1), and had no effect on runt-related transcription factor 2 (Runx2) and Osterix (Osx) mRNA levels. PAS activation (plasmin 5 µg/µl) significantly increased Col1a1 and decreased Bglap mRNA levels (p < .05). Together, our findings shed new light on the potential role of plasminogen signaling pathway in the control of the amelogenin isoform-mediated response in cementoblasts and provide new insights into the development of targeted therapies.

Novel rare frameshift variation in aggressive periodontitis: Exomic and familial-screening analysis

BACKGROUND

Aggressive periodontitis (AgP), currently periodontitis grade C, presents early onset, rapid progression, and a poorly established genetic association. Thus, this study aimed to identify genetic variants associated with AgP via whole exome sequencing (WES) through a familial screening approach.

METHODS

WES was performed in two nuclear families, including a proband and a parent affected by AgP and an unaffected parent and sibling. Common variants among affected individuals, excluding those common to healthy people, from each family, composed the data set associated with AgP. In silico analysis evaluated the impact of each variant on protein structure and protein-protein interactions. Moreover, identified deleterious variants were validated in a populational analysis (n = 96).

RESULTS

The missense single nucleotide variations (SNVs) rs142548867 in EEFSEC (c.668C>T), rs574301770 in ZNF136 (c.466C>G), and rs72821893 in KRT25 (c.800G>A) and the frameshift indels rs37146475 in GPRC6A (c.2323-2324insT) and c.1366_1372insGGAGCAG in ELN were identified in AgP and have a predicted functional impact on proteins. In silico analysis indicated that the indel in GPRC6A generates a loss of the C-terminal tail of the Gprca protein. Furthermore, this SNV was significantly associated with AgP in a population-based investigation.

CONCLUSION

Novel frameshift variation in GPRC6A (c.2323-2324insT) was identified as a potential genetic alteration associated with AgP occurrence.

A novel combination of biallelic ALPL mutations associated with adult hypophosphatasia: A phenotype-genotype association and computational analysis study

Hypophosphatasia (HPP) is an inherited metabolic disorder that causes defective skeletal and dental mineralization. HPP exhibits a markedly heterogeneous range of clinical manifestations caused by dysfunction of the tissue-nonspecific isozyme of alkaline phosphatase (TNSALP), resulting from loss-of-function mutations in the ALPL gene. HPP has been associated with predominantly missense mutations in ALPL, and a number of compound heterozygous genotypes have been identified. Here, we describe a case of a subject with adult-onset HPP caused by a novel combination of missense mutations p.Gly473Ser and p.Ala487Val, resulting in chronic musculoskeletal pain, myopathy, persistent fatigue, vomiting, and an uncommon dental phenotype of short-rooted permanent teeth. Pedigree and biochemical analysis indicated that severity of symptoms was correlated with levels of residual ALP activity, and co-segregated with the p.Gly473Ser missense mutation. Bioinformatic analysis to predict the structural and functional impact of each of the point mutations in the TNSALP molecule, and its potential contribution to the clinical symptoms, revealed that the affected Gly473 residue is localized in the homodimer interface and predicted to have a dominant negative effect. The affected Ala487 residue was predicted to bind to Tyr479, which is closely located the N-terminal α-helix of TNSALP monomer 2, suggesting that both changes may impair dimer stability and catalytic functions. In conclusion, these findings assist in defining genotype-phenotype associations for HPP, and further define specific sites within the TNSALP molecule potentially related to neuromuscular manifestations in adult HPP, allowing for a better understanding of HPP pathophysiology.

Membrane proteome characterization of periodontal ligament cell sets from deciduous and permanent teeth

BACKGROUND

Physiological roles for the periodontal ligament (PDL) include tooth eruption and anchorage, force absorption, and provision of proprioceptive information. Despite the advances in understanding the biology of PDL cells, there is a lack of information regarding the molecular signature of deciduous (DecPDL) and permanent (PermPDL) PDL tissues. Thus, the present study was designed to characterize the membrane proteome of DecPDL and PermPDL cells.

METHODS

Primary PDL cells were obtained (n = 6) and a label-free quantitative proteome of cell membrane-enriched components was performed. Proteome findings were validated by quantitative polymerase chain reaction and Western blot assays in fresh human tissues (n = 8) and primary cell cultures (n = 6). In addition, confocal microscopy was used to verify the expression of target factors in the PDL cell cultures.

RESULTS

Comparative gene ontology enrichment analysis evidenced that most stickling differences involved "endomembrane system" (PICALM, STX4, and LRP10), "hydrolase activity" (NCSTN and XRCC6), "protein binding" (PICALM, STX4, GPNMB, VASP, extended-synaptotagmin 2 [ESYT2], and leucine-rich repeat containing 15 [LRRC15]), and "isomerase activity" (FKBP8). Data are available via ProteomeXchange with identifier PXD010226. At the transcript level, high PICALM in DecPDL and ESYT2 and LRRC15 in PermPDL were confirmed in fresh PDL tissues. Furthermore, Western blot analysis confirmed increased levels of PICALM, LRRC15, and ESYT2 in cells and/or fresh tissues, and confocal microscopy confirmed the trends for PICALM and LRRC15 expression in PDL cells.

CONCLUSION

We report the first comprehensive characterization of the membrane protein machinery of DecPDL and PermPDL cells, and together, we identified a distinct molecular signature for these cell populations, including unique proteins for DecPDL and PermPDL.

Periodontitis in Chédiak-Higashi Syndrome: An Altered Immunoinflammatory Response

Chédiak-Higashi syndrome (CHS), a rare autosomal recessive disorder caused by mutations in the lysosomal trafficking regulator gene (LYST), is associated with aggressive periodontitis. It is suggested that LYST mutations affect the toll-like receptor (TLR)-mediated immunoinflammatory response, leading to frequent infections. This study sought to determine the periodontal status of patients with classic (severe) and atypical (milder) forms of CHS and the immunoregulatory functions of gingival fibroblasts in CHS patients. In contrast to aged-matched healthy controls, atypical (n = 4) and classic (n = 3) CHS patients presented with mild chronic periodontitis with no evidence of gingival ulceration, severe tooth mobility, or premature exfoliation of teeth. As a standard of care, all classic CHS patients had undergone bone marrow transplantation (BMT). Primary gingival fibroblasts obtained from atypical and BMT classic CHS patients displayed higher protein expression of TLR-2 (1.81-fold and 1.56-fold, respectively) and decreased expression of TLR-4 (-2.5-fold and -3.85-fold, respectively) at baseline when compared with healthy control gingival fibroblasts. When challenged with whole bacterial extract of Fusobacterium nucleatum, both atypical and classic CHS gingival fibroblasts failed to up-regulate TLR-2 and TLR-4 expression when compared with their respective untreated groups and control cells. Cytokine multiplex analysis following F. nucleatum challenge showed that atypical CHS gingival fibroblasts featured significantly increased cytokine expression (interleukin [IL]-2, IL-4, IL-5, IL-6, IL-10, IL-12, interferon-γ, tumor necrosis factor-α), whereas classic CHS cells featured similar/decreased cytokine expression when compared with treated control cells. Collectively, these results suggest that LYST mutations in CHS patients affect TLR-2 and TLR-4 expression/function, leading to dysregulated immunoinflammatory response, which in turn may influence the periodontal phenotype noted in CHS patients. Furthermore, our results suggest that atypical CHS patients and classic CHS patients who undergo BMT early in life are less susceptible to aggressive periodontitis and that hematopoietic cells play a critical role in mitigating the risk of aggressive periodontitis in CHS. Knowledge Transfer Statement: Results from this study can be used to create awareness among clinicians and researchers that not all CHS patients exhibit historically reported aggressive periodontitis, especially if they have atypical CHS disease or have received bone marrow transplantation. LYST mutations in CHS patients may affect TLR-2 and TLR-4 expression/function leading to dysregulated immunoinflammatory response, which in turn may influence the periodontal phenotype noted in CHS patients.

Computational analysis for GNAQ mutations: New insights on the molecular etiology of Sturge-Weber syndrome

Somatic activating mutations in the GNAQ have been recently associated with several congenital genetic disorders and tumors; however, the molecular mechanism/etiology that leads to GNAQ somatic mosaic mutation are unknown. Here, we reported a case of Sturge-Weber Syndrome (SWS) manifesting cutaneous vascular malformations (hemifacial Port-wine stain), cerebral and ocular vascular abnormalities (including epilepsy and glaucoma) and harboring a c.548G>A (p.R183Q) somatic mosaic mutation in GNAQ. Computational modeling studies were performed to assistant with the comprehension of the functional impact of p.R183Q and p.Q209L mutations in GNAQ, which encodes a G protein subunit alpha q (Gαq). The p.R183Q mutation was predicted to abolish hydrogen bonds between R183 residue and GDP molecule, destabilizing the inactive GDP-bound conformation of the Gαq mutants. Furthermore, replacement of R183 by Q183 residue was predicted to promote conformation changes in protein surface features affecting the switch I region, a key region that undergoes conformational changes triggered by receptor binding during signal transduction. In addition, replacement of Q209 by L209 residue was predicted to affect the molecular interaction between Gαq and Gβ subunit, impairing formation of the inactive heterotrimeric complex. These findings, in association with PPI network analysis, indicate that p.R183Q and p.Q209L mutations result in the over-activation of different downstream effectors, which in turn will determine the distinct cell responses and phenotype. These findings bring new insights on molecular etiology of vascular malformations associated to SWS and on different mechanisms underlying hyperactivation of downstream pathways to Gαq.

Detection of virulence-associated genes in pathogenic and commensal avian Escherichia coli isolates

Poultry colibacillosis due to Avian Pathogenic Escherichia coli (APEC) is responsible for several extra-intestinal pathological conditions, leading to serious economic damage in poultry production. The most commonly associated pathologies are airsacculitis, colisepticemia, and cellulitis in broiler chickens, and salpingitis and peritonitis in broiler breeders. In this work a total of 66 strains isolated from dead broiler breeders affected with colibacillosis and 61 strains from healthy broilers were studied. Strains from broiler breeders were typified with serogroups O2, O18, and O78, which are mainly associated with disease. The serogroup O78 was the most prevalent (58%). All the strains were checked for the presence of 11 virulence genes: 1) arginine succinyltransferase A (astA); ii) E.coli hemeutilization protein A (chuA); iii) colicin V A/B (cvaA/B); iv) fimbriae mannose-binding type 1 (fimC); v) ferric yersiniabactin uptake A (fyuA); vi) iron-repressible high-molecular-weight proteins 2 (irp2); vii) increased serum survival (iss); viii) iron-uptake systems of E.coli D (iucD); ix) pielonefritis associated to pili C (papC); x) temperature sensitive haemaglutinin (tsh), and xi) vacuolating autotransporter toxin (vat), by Multiplex-PCR. The results showed that all genes are present in both commensal and pathogenic E. coli strains. The iron uptake-related genes and the serum survival gene were more prevalent among APEC. The adhesin genes, except tsh, and the toxin genes, except astA, were also more prevalent among APEC isolates. Except for astA and tsh, APEC strains harbored the majority of the virulence-associated genes studied and fimC was the most prevalent gene, detected in 96.97 and 88.52% of APEC and AFEC strains, respectively. Possession of more than one iron transport system seems to play an important role on APEC survival.

Effect of Different Sensitization Events on HLA Alloimmunization in Kidney Transplantation Candidates

BACKGROUND

HLA alloimmunization is caused by sensitization events (SEs), such as transfusion, pregnancy, or previous organ transplantation, and the effects of particular SEs have not been thoroughly studied. Our aim was to evaluate how each SE affected HLA alloimmunization by considering Luminex assays.

METHODS

Sera from 722 kidney transplantation candidates were screened per protocol by means of Luminex assays to determine the presence of anti-HLA class I/II antibodies; positive sera underwent single-antigen assay to determine the presence of specific antibodies against HLA A, B, C, DR, DQ, DP loci (positivity if median fluorescence intensity values were >1,000). The effect of each SE was analyzed considering only patients exposed to 1 kind of sensitization.

RESULTS

In the 453 candidates with ≥1 SE, anti-HLA class I positivity rates were significantly higher in patients with previous transfusion (18.9%; P = .014), pregnancy (38.3%; P < .001) or transplant (75%; P < .001) compared with those with no SE (similar results for class II). The strength (median fluorescence intensity) of specific antibodies was significantly higher in patients with previous transplantation than in those with previous transfusion for HLA-A (8,017 vs 2,302; P = .02), HLA-B (7,765 vs 2,901; P = .018), and HLA-DR (9,835 vs 2,060; P = .003). Other anti-HLA antibody strengths were similar between patients with previous pregnancy or transplantation.

CONCLUSIONS

Presence of any SE analyzed was associated with a higher prevalence of anti-HLA antibodies for class I ± II compared with nonsensitized patients. Transplantation had the strongest immunization effect on both classes, followed by pregnancy and then transfusion.

Exposure of periodontal ligament progenitor cells to lipopolysaccharide from Escherichia coli changes osteoblast differentiation pattern

Periodontal ligament mesenchymal stem cells (PDLMSCs) are an important alternative source of adult stem cells and may be applied for periodontal tissue regeneration, neuroregenerative medicine, and heart valve tissue engineering. However, little is known about the impact of bacterial toxins on the biological properties of PDLSMSCs, including self-renewal, differentiation, and synthesis of extracellular matrix.

Clinical features and outcome of typhoid fever and invasive non-typhoidal salmonellosis in a tertiary hospital in Belgium: analysis and review of the literature

OBJECTIVES

Typhoid fever (TF) occurs rarely in industrialized countries because of advances in health care and improvement of drinking water. Conversely, non-typhoid salmonellosis (NTS) remains widespread, because of food contamination or asymptomatic carriage. Non-typhoid salmonellosis can be severe when becoming invasive non-typhoid salmonellosis (iNTS). Although established prognostic indicators of the two pathologies are different, direct comparisons between iNTS and TF in the literature remain scarce. The purpose of this study was to analyse and compare demographic, clinical features and outcome of hospitalized patients with TF and iNTS.

METHODS

Demographic, clinical features and outcome were retrospectively analysed in a series of patients hospitalized between 2007 and 2012.

RESULTS

A total of 33 patients were enrolled, including 13 with established TF and 20 with iNTS. No differences between TF and iNTS patients were observed in incidence of fever, abdominal cramps, diarrhoea, headache, nausea and vomiting and duration of antibiotic therapy (≤ 7 days in both groups). Although the clinical outcome of TF patients was identical to that of iNTS patients, including incidence of complications, length of hospitalization and mortality (1/13 (7.7%) vs 2/20 (10%), P = 0.43), comorbidities were less frequent in the TF group than in the iNTS group (2/13 vs 15/20, P = 0.003).

CONCLUSION

The clinical profile and outcome of TF patients are similar to those with iNTS. Although comorbidities are more often associated with iNTS, the results of our study suggest that clinical management of these two diseases should remain similar.

G-quadruplex formation enhances splicing efficiency of PAX9 intron 1

G-quadruplexes are secondary structures present in DNA and RNA molecules, which are formed by stacking of G-quartets (i.e., interaction of four guanines (G-tracts) bounded by Hoogsteen hydrogen bonding). Human PAX9 intron 1 has a putative G-quadruplex-forming region located near exon 1, which is present in all known sequenced placental mammals. Using circular dichroism (CD) analysis and CD melting, we showed that these sequences are able to form highly stable quadruplex structures. Due to the proximity of the quadruplex structure to exon-intron boundary, we used a validated double-reporter splicing assay and qPCR to analyze its role on splicing efficiency. The human quadruplex was shown to have a key role on splicing efficiency of PAX9 intron 1, as a mutation that abolished quadruplex formation decreased dramatically the splicing efficiency of human PAX9 intron 1. The less stable, rat quadruplex had a less efficient splicing when compared to human sequences. Additionally, the treatment with 360A, a strong ligand that stabilizes quadruplex structures, further increased splicing efficiency of human PAX9 intron 1. Altogether, these results provide evidences that G-quadruplex structures are involved in splicing efficiency of PAX9 intron 1.

Living versus cadaveric-donor renal transplant recipients: a comparison on sexual function

Erectile dysfunction is experienced by 50% of men with end-stage renal disease (ESRD) and uremia. The origin of this dysfunction is multifactorial. The aim of this study was to compare living donor versus cadaveric donor transplant recipients regarding male sexual function. Seventy-seven sexually active male kidney transplant recipients (44 from living donors; 33 from cadaveric donors) were randomly selected from our single-center prospective database of 2016 renal transplants. Epidemiological and clinical data were collected between June 2010 and June 2011. Male sexual function was evaluated with the International Index of Erectile Function questionnaire (IIEF-15). We assessed the prevalence of male sexual dysfunction according to established cutoff points for each of the IIEF-15 domains. Mann-Whitney and Pearson's chi- square statistical tests were used to compare continuous and categorical variables, respectively. The median age at the time of completion of the questionnaires was 43 and 51 years (P = .003) with median times from transplantation was of 36 and 42 months for living donor and cadaveric donor recipients, respectively (P = .31). Median durations of ESRD before surgery were 17.5 and 57 months for living donor and cadaveric donor recipients, respectively (P < .001). Living donor and cadaveric donor recipients had median creatinine clearance values of 55 and 57 mL/min, respectively (P = .44). Median time after renal transplantation for first sexual intercourse was 1 and 2 months for living donor and cadaveric donor recipients, respectively (P = .35). Median body mass indices for living donor and cadaveric donor recipients were 24.8 and 24, respectively (P = .31). Regarding sexual function domains, there were significant differences only for intercourse satisfaction. In our cohort, living donor recipients tended to be younger, have shorter time of ESRD, and less incidence of hypertension or diabetes mellitus but with greater tobacco use. In conclusion, living donor transplantation exerted a favorable impact on sexual function.

Novel ALPL genetic alteration associated with an odontohypophosphatasia phenotype

Hypophosphatasia (HPP) is an inherited disorder of mineral metabolism caused by mutations in ALPL, encoding tissue non-specific alkaline phosphatase (TNAP). Here, we report the molecular findings from monozygotic twins, clinically diagnosed with tooth-specific odontohypophosphatasia (odonto-HPP). Sequencing of ALPL identified two genetic alterations in the probands, including a heterozygous missense mutation c.454C>T, leading to change of arginine 152 to cysteine (p.R152C), and a novel heterozygous gene deletion c.1318_1320delAAC, leading to the loss of an asparagine residue at codon 440 (p.N440del). Clinical identification of low serum TNAP activity, dental abnormalities, and pedigree data strongly suggests a genotype-phenotype correlation between p.N440del and odonto-HPP in this family. Computational analysis of the p.N440del protein structure revealed an alteration in the tertiary structure affecting the collagen-binding site (loop 422-452), which could potentially impair the mineralization process. Nevertheless, the probands (compound heterozygous: p.[N440del];[R152C]) feature early-onset and severe odonto-HPP phenotype, whereas the father (p.[N440del];[=]) has only moderate symptoms, suggesting p.R152C may contribute or predispose to a more severe dental phenotype in combination with the deletion. These results assist in defining the genotype-phenotype associations for odonto-HPP, and further identify the collagen-binding site as a region of potential structural importance for TNAP function in the biomineralization.

Periodontitis and atherosclerosis: an observational study

BACKGROUND

Poor oral health has been related with cardiovascular diseases. Specifically, periodontitis has been implicated in the pathogenesis of atherosclerosis. Our aim was to evaluate the relationship between the degree of carotid atherosclerosis and severity of periodontitis in a patient cohort.

METHODS

Fifty adult patients receiving carotid duplex scans in a cerebral hemodynamics lab were included in the study. Ultrasound protocol included measurement of carotid intima-media thickness (IMT), which is a marker of atherosclerosis, and characterization of any atherosclerotic plaques in the cervical common and internal carotid arteries. Patients were divided into two main groups: the test group had IMT ≥ 1 mm or the presence of any carotid atherosclerotic plaque, and the control group had IMT < 1 mm and absence of atherosclerotic plaques. Periodontal evaluation was performed in all the teeth and characterized according to the clinical attachment level, which between 1 mm and 2 mm was classified as slight, 3 mm and 4 mm as moderate and ≥5 mm as severe.

RESULTS

The control group included 15 (30%), while the test group included 35 (70%) subjects. The most common diagnosis was severe periodontitis (40%); moderate and slight periodontitis were also frequent occurrences (32% and 28%, respectively). In the control group, 53.3% had slight, 33.3% had moderate and 13.3% had severe periodontitis. In the test group, those percentages were respectively 22.2%, 44.4% and 33.3%. Patients with atheroma plaque had the highest percentage of severe periodontitis (70.6%). More severe periodontitis was related to atherosclerosis (P = 0.007).

CONCLUSION

This study showed an association between periodontitis severity and carotid atherosclerosis, suggesting that periodontal disease might be a risk indicator for atherosclerotic disease.

Hypophosphatasia-associated deficiencies in mineralization and gene expression in cultured dental pulp cells obtained from human teeth

INTRODUCTION

Mutations in the gene ALPL in hypophosphatasia (HPP) reduce the function of tissue nonspecific alkaline phosphatase, and the resulting increase in pyrophosphate (PP(i)) contributes to bone and tooth mineralization defects by inhibiting physiologic calcium-phosphate (P(i)) precipitation. Although periodontal phenotypes are well documented, pulp/dentin abnormalities have been suggested in the clinical literature although reports are variable and underlying mechanisms remains unclear. In vitro analyses were used to identify mechanisms involved in HPP-associated pulp/dentin phenotypes.

METHODS

Primary pulp cells cultured from HPP subjects were established to assay alkaline phosphatase (ALP) activity, mineralization, and gene expression compared with cells from healthy controls. Exogenous P(i) was provided to the correct P(i)/PP(i) ratio in cell culture.

RESULTS

HPP cells exhibited significantly reduced ALP activity (by 50%) and mineral nodule formation (by 60%) compared with the controls. The expression of PP(i) regulatory genes was altered in HPP pulp cells, including reduction in the progressive ankylosis gene (ANKH) and increased ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). Odontoblast marker gene expression was disrupted in HPP cells, including reduced osteopontin (OPN), dentin matrix protein 1 (DMP1), dentin sialophosphoprotein (DSPP), and matrix extracellular phosphoprotein (MEPE). The addition of P(i) provided a corrective measure for mineralization and partially rescued the expression of some genes although cells retained altered messenger RNA levels for PP(i)-associated genes.

CONCLUSIONS

These studies suggest that under HPP conditions pulp cells have the compromised ability to mineralize and feature a disrupted odontoblast profile, providing a first step toward understanding the molecular mechanisms for dentin phenotypes observed in HPP.

Correction of hypophosphatasia-associated mineralization deficiencies in vitro by phosphate/pyrophosphate modulation in periodontal ligament cells

BACKGROUND

Mutations in the liver/bone/kidney alkaline phosphatase (ALPL) gene in hypophosphatasia (HPP) reduce the function of tissue non-specific alkaline phosphatase (ALP), resulting in increased pyrophosphate (PP(i)) and a severe deficiency in acellular cementum. We hypothesize that exogenous phosphate (P(i)) would rescue the in vitro mineralization capacity of periodontal ligament (PDL) cells harvested from HPP-diagnosed patients, by correcting the P(i)/PP(i) ratio and modulating expression of genes involved with P(i)/PP(i) metabolism.

METHODS

Ex vivo and in vitro analyses were used to identify mechanisms involved in HPP-associated PDL/tooth root deficiencies. Constitutive expression of PP(i)-associated genes was contrasted in PDL versus pulp tissues obtained from healthy individuals. Primary PDL cell cultures from patients with HPP (monozygotic twin males) were established to assay ALP activity, in vitro mineralization, and gene expression. Exogenous P(i) was provided to correct the P(i)/PP(i) ratio.

RESULTS

PDL tissues obtained from healthy individuals featured higher basal expression of key PP(i) regulators, genes ALPL, progressive ankylosis protein (ANKH), and ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), versus paired pulp tissues. A novel ALPL mutation was identified in the twin patients with HPP enrolled in this study. Compared to controls, HPP-PDL cells exhibited significantly reduced ALP and mineralizing capacity, which were rescued by addition of 1 mM P(i). Dysregulated expression of PP(i) regulatory genes ALPL, ANKH, and ENPP1 was also corrected by adding P(i), although other matrix markers evaluated in our study remained downregulated.

CONCLUSION

These findings underscore the importance of controlling the P(i)/PP(i) ratio toward development of a functional periodontal apparatus and support P(i)/PP(i) imbalance as the etiology of HPP-associated cementum defects.