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1.
Am J Otolaryngol ; 45(4): 104314, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38663327

RESUMEN

BACKGROUND: The endoscopic modified medial maxillectomy (MMM) and prelacrimal approach (PLA) are two routinely performed endoscopic approaches to the maxillary sinus when access via a middle meatal antrostomy is insufficient. However, there is no data in the literature that has compared outcomes and complication profile between the two procedures to determine which approach is superior. OBJECTIVE: To compare the approach related morbidity of PLA and MMM. METHODS: A retrospective cohort study of all consecutive adult patients undergoing either MMM or PLA from 2009 to 2023 were identified. The primary outcome was development of epistaxis, paraesthesia, lacrimal injury, iatrogenic sinus dysfunction within a minimum of 3 months post-operative follow up. RESULTS: 39 patients (44 sides) underwent PLA and 96 (96 sides) underwent MMM. There were no statistically significant differences between the rates of paraesthesia (9.1 % vs 14.6 %, p = 0.367) or prolonged paraesthesia (2.3 % vs 5.2 %, p = 0.426), iatrogenic maxillary sinus dysfunction (2.3 % vs 5.2 %, p = 0.426) or adhesions requiring removal (4.5 % vs 4.2 %, p = 0.918). No cases of epiphora or nasal cavity stenosis occurred in either arm in our study. CONCLUSIONS: According to our data, the endoscopic modified medial maxillectomy and prelacrimal approach are both equally safe approaches with their own benefits to access.


Asunto(s)
Endoscopía , Neoplasias del Seno Maxilar , Seno Maxilar , Humanos , Masculino , Femenino , Endoscopía/métodos , Estudios Retrospectivos , Persona de Mediana Edad , Neoplasias del Seno Maxilar/cirugía , Seno Maxilar/cirugía , Anciano , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Adulto , Resultado del Tratamiento , Epistaxis/etiología , Epistaxis/cirugía , Estudios de Cohortes , Parestesia/etiología
2.
Behav Sci Law ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38635450

RESUMEN

Technology-facilitated sexual abuse refers to the use of information and communication technologies to facilitate both virtual and in-person sexual crimes. Research on this topic has focused on rates, risk factors, and consequences. This scoping review aims to understand whether and how forensic psychological procedures are adapted to assess adolescent victims and how Internet-based information might be useful as complementary data. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extensions for Scoping Reviews guidelines, searches were conducted in April 2023 in five electronic databases to include Portuguese, Spanish, or English quantitative, qualitative, or mixed-method peer-reviewed studies. Of the 2523 studies, six were considered eligible. Identified procedures include forensic interviews following the National Institute for Child Health and Human Development Protocol, and risk and trauma assessments. While discussing technology's role in abuse during interviews was informative, confronting adolescents with evidence of their abuse had adverse effects on their testimony and recovery. The assessment tools often had a narrow focus or overlooked the abuse unless explicitly disclosed, implied a referral, or when safeguarding concerns were raised. Clinical, forensic, and criminal implications are elaborated.

3.
Trauma Violence Abuse ; 25(2): 1382-1396, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37272340

RESUMEN

Child sexual abuse (CSA) is widely recognized as a global public health problem with negative consequences for victims, their families, and society. The child's testimony is essential to the case outcome, given the frequent absence of physical or biological evidence of the abusive acts. Thus, the child forensic interview plays a decisive role in criminal investigation. The present scoping review aims to identify and describe the judicial procedures for collecting CSA victims' testimony using an evidence-based approach and a structured methodology. The review followed Preferred Reporting Items of Systematic Reviews and Meta-Analysis-Scoping Review guidelines. Studies were identified through manual reference checking and in four electronic databases: PsycARTICLES, PubMed, SCOPUS, and Web of Science. In all, 146 studies were identified according to the defined inclusion criteria, that is, empirical studies identifying judicial procedures to collect CSA victims' testimony, published in English or Portuguese. In total, 30 different forensic interview procedures to collect the child victim's testimony were found. The National Institute for Child Health and Human Development investigative interview protocol was the most frequently mentioned. Despite the variety of protocols, it was possible to conclude that they have a similar general structure. This review also identified gaps in interviewing practices with CSA victims. The scoping review corroborates the importance of forensic interviews with CSA victims, stating its implications for criminal investigation, the legal system, and the child's recovery process.


Asunto(s)
Abuso Sexual Infantil , Maltrato a los Niños , Niño , Humanos , Aplicación de la Ley , Revisiones Sistemáticas como Asunto
4.
Pathobiology ; 90(5): 333-343, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37040716

RESUMEN

INTRODUCTION: Genomic variants of the human papillomavirus type 16 (HPV16) are thought to play differential roles in the susceptibility to head and neck squamous cell carcinomas (HNSCC) and its biological behaviour. This study aimed to establish the prevalence of HPV16 variants in an HNSCC cohort and associate them with clinical pathological characteristics and patient survival. METHODS: We retrieved samples and clinical data from 68 HNSCC patients. DNA samples were available from tumour biopsy at the time of the primary diagnosis. Targeted next-generation sequencing was used to obtain whole-genome sequences, and variants were established based on phylogenetic classification. RESULTS: 74% of samples clustered in lineage A, 5.7% in lineage B, 2.9% in lineage C, and 17.1% in lineage D. Comparative genome analysis revealed 243 single nucleotide variations. Of these, one hundred were previously reported, according to our systematic review. No significant associations with clinical pathological variables or patient survival were observed. The E6 amino acid variations E31G, L83V, and D25E and E7 N29S, associated with cervical cancer, were not observed, except for N29S in a single patient. CONCLUSION: These results provide a comprehensive genomic map of HPV16 in HSNCC, highlighting tissue-specific characteristics which will help design tailored therapies for cancer patients.

5.
J Infect ; 85(1): 64-74, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35609706

RESUMEN

COVID-19 local outbreak response relies on subjective information to reconstruct transmission chains. We assessed the concordance between epidemiologically linked cases and viral genetic profiles, in the Baixo Vouga Region (Portugal), from March to June 2020. A total of 1925 COVID-19 cases were identified, with 1143 being assigned to 154 epiclusters. Viral genomic data was available for 128 cases. Public health authorities identified two large epiclusters (280 and 101 cases each) with a central role on the spread of the disease. Still, the genomic data revealed that each epicluster included two distinct SARS-CoV-2 genetic profiles and thus more than one transmission network. We were able to show that the initial transmission dynamics reconstruction was most likely accurate, but the increasing dimension of the epiclusters and its extension to densely populated settings (healthcare and nursing home settings) triggered the misidentification of links. Genomics was also key to resolve some sporadic cases and misidentified direction of transmission. The epidemiological investigation showed a sensitivity of 70%-86% to detect transmission chains. This study contributes to the understanding of the hurdles and caveats associated with the epidemiological investigation of hundreds of community cases in the context of a massive outbreak caused by a highly transmissible and new respiratory virus.


Asunto(s)
COVID-19 , COVID-19/epidemiología , Brotes de Enfermedades , Genoma Viral , Genómica , Humanos , SARS-CoV-2/genética
6.
Emerg Infect Dis ; 28(2): 331-337, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34876242

RESUMEN

We developed a case-case study to compare mRNA vaccine effectiveness against Delta versus Alpha coronavirus variants. We used data on 2,097 case-patients with PCR-positive severe acute respiratory syndrome coronavirus 2 infections reported in Portugal during May-July 2021. We estimated the odds of vaccine breakthrough infection in Delta-infected versus Alpha-infected patients by using conditional logistic regression adjusted for age group and sex and matched by the week of diagnosis. We compared reverse-transcription PCR cycle threshold values by vaccination status and variant as an indirect measure of viral load. We found significantly higher odds of vaccine breakthrough infection in Delta-infected patients than in Alpha-infected patients (odds ratio 1.96 [95% CI 1.22-3.14]), suggesting lower effectiveness of the mRNA vaccines in preventing infection with the Delta variant. We estimated lower mean cycle threshold values for the Delta cases (mean difference -2.10 [95% CI -2.74 to -1.47]), suggesting higher infectiousness than the Alpha variant.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , SARS-CoV-2 , Vacunación , Vacunas Sintéticas , Vacunas de ARNm
7.
Int J Infect Dis ; 112: 318-320, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34547489

RESUMEN

Re-positivity of SARS-CoV-2 tests is widely reported, raising discussion about guidance for patient discharge and ending isolation. The unsuccessful recovery of replication-competent virus and/or absence of secondary cases has suggested that re-positive patients are not contagious. This study reports SARS-CoV-2 re-positivity in a healthcare professional 16 days after three negative tests, with viral genome sequencing supporting contagiousness leading to secondary cases.


Asunto(s)
COVID-19 , SARS-CoV-2 , Atención a la Salud , Genoma Viral , Humanos , Alta del Paciente
8.
Euro Surveill ; 26(10)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33706862

RESUMEN

We show that the SARS-CoV-2 B.1.1.7 lineage is highly disseminated in Portugal, with the odds of B.1.1.7 proportion increasing at an estimated 89% (95% confidence interval: 83-95%) per week until week 3 2021. RT-PCR spike gene target late detection (SGTL) can constitute a useful surrogate to track B.1.1.7 spread, besides the spike gene target failure (SGTF) proxy. SGTL/SGTF samples were associated with statistically significant higher viral loads, but not with substantial shift in age distribution compared to non-SGTF/SGTL cases.


Asunto(s)
COVID-19/virología , SARS-CoV-2/genética , COVID-19/transmisión , Humanos , Portugal/epidemiología , Glicoproteína de la Espiga del Coronavirus/genética
9.
Int J Neural Syst ; 30(5): 2050023, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32380924

RESUMEN

The training procedure of the minimal learning machine (MLM) requires the selection of two sets of patterns from the training dataset. These sets are called input reference points (IRP) and output reference points (ORP), which are used to build a mapping between the input geometric configurations and their corresponding outputs. In the original MLM, the number of input reference points is the hyper-parameter and the patterns are chosen at random. Therefore, the conventional proposal does not consider which patterns will belong to each reference point group, since the model does not implement an appropriate way of selecting the most suitable patterns as reference points. Such an approach can impact on the decision function in terms of smoothness, resulting in high complexity models. This paper introduces a new approach to select IRP for MLM applied to classification tasks. The optimally selected minimal learning machine (OS-MLM) relies on the multiresponse sparse regression (MRSR) ranking method and the leave-one-out (LOO) criterion to sort the patterns in terms of relevance and select an appropriate number of input reference points, respectively. The experimental assessment conducted on UCI datasets reports the proposal was able to produce sparser models and achieve competitive performance when compared to the regular strategy of selecting MLM input RPs.


Asunto(s)
Aprendizaje Automático , Modelos Teóricos , Reconocimiento de Normas Patrones Automatizadas , Humanos , Análisis de Regresión
10.
IEEE Trans Neural Netw Learn Syst ; 31(10): 4389-4393, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31831445

RESUMEN

We show theoretical similarities between the least squares support vector regression (LS-SVR) model with a radial basis functions (RBFs) kernel and maximum a posteriori (MAP) inference on Bayesian RBF networks with a specific Gaussian prior on the regression weights. Although previous articles have pointed out similar expressions between those learning approaches, we explicitly and formally state the existing correspondences. We empirically demonstrate our result by performing computational experiments with standard regression benchmarks. Our findings open a range of possibilities to improve LS-SVR by borrowing strength from well-established developments in Bayesian methodology.

11.
Front Microbiol ; 10: 831, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31130921

RESUMEN

Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli strain C999 was isolated of a Spanish patient with urinary tract infection. Previous genotyping indicated that this strain presented a multidrug-resistance phenotype and carried beta-lactamase genes encoding CTX-M-15, TEM-1, and OXA-1 enzymes. The whole-cell proteome, and the membrane, cytoplasmic, periplasmic and extracellular sub-proteomes of C999 were obtained in this work by two-dimensional gel electrophoresis (2DE) followed by fingerprint sequencing through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS). A total of 602 proteins were identified in the different cell fractions, several of which are related to stress response systems, cellular responses, and antibiotic and drug responses, consistent with the multidrug-resistance phenotype. In parallel, whole genome sequencing (WGS) and RNA sequencing (RNA-Seq) was done to identify and quantify the genes present and expressing. The in silico prediction following WGS confirmed our strain as being serotype O25:H4 and sequence type ST131. The presence of proteins related to antibiotic resistance and virulence in an O25:H4-ST131 E. coli clone are serious indicators of the continued threat of antibiotic resistance spread amongst healthcare institutions. On a positive note, a multiomics approach can facilitate surveillance and more detailed characterization of virulent bacterial clones from hospital environments.

12.
Microorganisms ; 5(2)2017 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-28368366

RESUMEN

Klebsiella pneumoniae is a prominent etiological agent of healthcare associated infections (HAIs). In this context, multidrug-resistant and biofilm-producing bacteria are of special public health concern due to the difficulties associated with treatment of human infections and eradication from hospital environments. Here, in order to study the impact of medical devices-associated materials on the biofilm dynamics, we performed biofilm phenotypic analyses through a classic and a new scanning electron microscopy (SEM) technique for three multidrug-resistant K. pneumoniae isolates growing on polystyrene and silicone. We also applied whole-genome sequencing (WGS) to search for genetic clues underlying biofilm phenotypic differences. We found major differences in the extracellular polymeric substances (EPS) content among the three strains, which were further corroborated by in-depth EPS composition analysis. WGS analysis revealed a high nucleotide similarity within the core-genome, but relevant differences in the accessory genome that may account for the detected biofilm phenotypic dissimilarities, such as genes already associated with biofilm formation in other pathogenic bacteria (e.g., genes coding haemogglutinins and haemolysins). These data reinforce that the research efforts to defeat bacterial biofilms should take into account that their dynamics may be contingent on the medical devices-associated materials.

13.
Sci Rep ; 7: 42471, 2017 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-28205536

RESUMEN

Helicobacter pylori genetic diversity is known to be influenced by mobile genomic elements. Here we focused on prophages, the least characterized mobile elements of H. pylori. We present the full genomic sequences, insertion sites and phylogenetic analysis of 28 prophages found in H. pylori isolates from patients of distinct disease types, ranging from gastritis to gastric cancer, and geographic origins, covering most continents. The genome sizes of these prophages range from 22.6-33.0 Kbp, consisting of 27-39 open reading frames. A 36.6% GC was found in prophages in contrast to 39% in H. pylori genome. Remarkably a conserved integration site was found in over 50% of the cases. Nearly 40% of the prophages harbored insertion sequences (IS) previously described in H. pylori. Tandem repeats were frequently found in the intergenic region between the prophage at the 3' end and the bacterial gene. Furthermore, prophage genomes present a robust phylogeographic pattern, revealing four distinct clusters: one African, one Asian and two European prophage populations. Evidence of recombination was detected within the genome of some prophages, resulting in genome mosaics composed by different populations, which may yield additional H. pylori phenotypes.


Asunto(s)
Genoma Viral , Genómica , Helicobacter pylori/virología , Mutagénesis Insercional , Profagos/genética , Genómica/métodos , Mosaicismo , Sistemas de Lectura Abierta , Filogenia , Análisis de Secuencia de ADN
14.
Sci Rep ; 6: 26261, 2016 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-27196677

RESUMEN

A first strong evidence of person-to-person transmission of Legionnaires' Disease (LD) was recently reported. Here, we characterize the genetic backbone of this case-related Legionella pneumophila strain ("PtVFX/2014"), which also caused a large outbreak of LD. PtVFX/2014 is phylogenetically divergent from the most worldwide studied outbreak-associated L. pneumophila subspecies pneumophila serogroup 1 strains. In fact, this strain is also from serogroup 1, but belongs to the L. pneumophila subspecies fraseri. Its genomic mosaic backbone reveals eight horizontally transferred regions encompassing genes, for instance, involved in lipopolysaccharide biosynthesis or encoding virulence-associated Dot/Icm type IVB secretion system (T4BSS) substrates. PtVFX/2014 also inherited a rare ~65 kb pathogenicity island carrying virulence factors and detoxifying enzymes believed to contribute to the emergence of best-fitted strains in water reservoirs and in human macrophages, as well as a inter-species transferred (from L. oakridgensis) ~37.5 kb genomic island (harboring a lvh/lvr T4ASS cluster) that had never been found intact within L. pneumophila species. PtVFX/2014 encodes another lvh/lvr cluster near to CRISPR-associated genes, which may boost L. pneumophila transition from an environmental bacterium to a human pathogen. Overall, this unique genomic make-up may impact PtVFX/2014 ability to adapt to diverse environments, and, ultimately, to be transmitted and cause human disease.


Asunto(s)
Genoma Bacteriano , Legionella pneumophila/genética , Enfermedad de los Legionarios/transmisión , Islas Genómicas , Humanos , Legionella pneumophila/patogenicidad , Filogenia , Portugal , Serogrupo , Factores de Virulencia/genética , Secuenciación Completa del Genoma
15.
Antimicrob Agents Chemother ; 60(6): 3323-32, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26976875

RESUMEN

Quaternary ammonium compounds (QAC) are widely used, cheap, and chemically stable disinfectants and topical antiseptics with wide-spectrum antimicrobial activities. Within this group of compounds, we recently showed that there are significant differences between the pharmacodynamics of n-alkyl quaternary ammonium surfactants (QAS) with a short (C12) alkyl chain when in vitro toxicities toward bacterial and mammalian epithelial cells are compared. These differences result in an attractive therapeutic window that justifies studying short-chain QAS as prophylactics for sexually transmitted infections (STI) and perinatal vertically transmitted urogenital infections (UGI). We have evaluated the antimicrobial activities of short-chain (C12) n-alkyl QAS against several STI and UGI pathogens as well as against commensal Lactobacillus species. Inhibition of infection of HeLa cells by Neisseria gonorrhoeae and Chlamydia trachomatis was studied at concentrations that were not toxic to the HeLa cells. We show that the pathogenic bacteria are much more susceptible to QAS toxic effects than the commensal vaginal flora and that QAS significantly attenuate the infectivity of N. gonorrhoeae and C. trachomatis without affecting the viability of epithelial cells of the vaginal mucosa. N-Dodecylpyridinium bromide (C12PB) was found to be the most effective QAS. Our results strongly suggest that short-chain (C12) n-alkyl pyridinium bromides and structurally similar compounds are promising microbicide candidates for topical application in the prophylaxis of STI and perinatal vertical transmission of UGI.


Asunto(s)
Antiinfecciosos/farmacología , Chlamydia trachomatis/efectos de los fármacos , Gonorrea/tratamiento farmacológico , Compuestos de Amonio Cuaternario/farmacología , Streptococcus/efectos de los fármacos , Tensoactivos/farmacología , Células HeLa , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Neisseria gonorrhoeae/efectos de los fármacos , Enfermedades de Transmisión Sexual/microbiología
17.
J Antimicrob Chemother ; 71(3): 641-54, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26679255

RESUMEN

OBJECTIVES: Broad-spectrum antimicrobial activity of quaternary ammonium surfactants (QAS) makes them attractive and cheap topical prophylactic options for sexually transmitted infections and perinatal vertically transmitted urogenital infections. Although attributed to their high affinity for biological membranes, the mechanisms behind QAS microbicidal activity are not fully understood. We evaluated how QAS structure affects antimicrobial activity and whether this can be exploited for use in prophylaxis of bacterial infections. METHODS: Acute toxicity of QAS to in vitro models of human epithelial cells and bacteria were compared to identify selective and potent bactericidal agents. Bacterial cell viability, membrane integrity, cell cycle and metabolism were evaluated to establish the mechanisms involved in selective toxicity of QAS. RESULTS: QAS toxicity normalized relative to surfactant critical micelle concentration showed n-dodecylpyridinium bromide (C12PB) to be the most effective, with a therapeutic index of ∼10 for an MDR strain of Escherichia coli and >20 for Neisseria gonorrhoeae after 1 h of exposure. Three modes of QAS antibacterial action were identified: impairment of bacterial energetics and cell division at low concentrations; membrane permeabilization and electron transport inhibition at intermediate doses; and disruption of bacterial membranes and cell lysis at concentrations close to the critical micelle concentration. In contrast, toxicity to mammalian cells occurs at higher concentrations and, as we previously reported, results primarily from mitochondrial dysfunction and apoptotic cell death. CONCLUSIONS: Our data show that short chain (C12) n-alkyl pyridinium bromides have a sufficiently large therapeutic window to be good microbicide candidates.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Compuestos de Amonio Cuaternario/química , Compuestos de Amonio Cuaternario/farmacología , Tensoactivos/química , Tensoactivos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos Locales/química , Antiinfecciosos Locales/farmacología , Antiinfecciosos Locales/uso terapéutico , División Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Humanos , Metabolismo/efectos de los fármacos , Viabilidad Microbiana/efectos de los fármacos , Neisseria gonorrhoeae/efectos de los fármacos , Neisseria gonorrhoeae/fisiología , Compuestos de Amonio Cuaternario/uso terapéutico , Tensoactivos/uso terapéutico
18.
PLoS One ; 10(7): e0133420, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26207372

RESUMEN

Research on the obligate intracellular bacterium Chlamydia trachomatis demands culture in cell-lines, but the adaptive process behind the in vivo to in vitro transition is not understood. We assessed the genomic and transcriptomic dynamics underlying C. trachomatis in vitro adaptation of strains representing the three disease groups (ocular, epithelial-genital and lymphogranuloma venereum) propagated in epithelial cells over multiple passages. We found genetic features potentially underlying phase variation mechanisms mediating the regulation of a lipid A biosynthesis enzyme (CT533/LpxC), and the functionality of the cytotoxin (CT166) through an ON/OFF mechanism. We detected inactivating mutations in CT713/porB, a scenario suggesting metabolic adaptation to the available carbon source. CT135 was inactivated in a tropism-specific manner, with CT135-negative clones emerging for all epithelial-genital populations (but not for LGV and ocular populations) and rapidly increasing in frequency (~23% mutants per 10 passages). RNA-sequencing analyses revealed that a deletion event involving CT135 impacted the expression of multiple virulence factors, namely effectors known to play a role in the C. trachomatis host-cell invasion or subversion (e.g., CT456/Tarp, CT694, CT875/TepP and CT868/ChlaDub1). This reflects a scenario of attenuation of C. trachomatis virulence in vitro, which may take place independently or in a cumulative fashion with the also observed down-regulation of plasmid-related virulence factors. This issue may be relevant on behalf of the recent advances in Chlamydia mutagenesis and transformation where culture propagation for selecting mutants/transformants is mandatory. Finally, there was an increase in the growth rate for all strains, reflecting gradual fitness enhancement over time. In general, these data shed light on the adaptive process underlying the C. trachomatis in vivo to in vitro transition, and indicates that it would be prudent to restrict culture propagation to minimal passages and check the status of the CT135 genotype in order to avoid the selection of CT135-negative mutants, likely originating less virulent strains.


Asunto(s)
Chlamydia trachomatis/genética , Regulación hacia Abajo , Factores de Virulencia/genética , Chlamydia trachomatis/metabolismo , Genoma Bacteriano , Genotipo , Polimorfismo Genético , Virulencia
19.
PLoS One ; 10(7): e0131695, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26131720

RESUMEN

Chlamydia trachomatis is the most important infectious cause of infertility in women with important implications in public health and for which a vaccine is urgently needed. Recent immunoproteomic vaccine studies found that four polymorphic membrane proteins (PmpE, PmpF, PmpG and PmpH) are immunodominant, recognized by various MHC class II haplotypes and protective in mouse models. In the present study, we aimed to evaluate genetic and protein features of Pmps (focusing on the N-terminal 600 amino acids where MHC class II epitopes were mapped) in order to understand antigen variation that may emerge following vaccine induced immune selection. We used several bioinformatics platforms to study: i) Pmps' phylogeny and genetic polymorphism; ii) the location and distribution of protein features (GGA(I, L)/FxxN motifs and cysteine residues) that may impact pathogen-host interactions and protein conformation; and iii) the existence of phase variation mechanisms that may impact Pmps' expression. We used a well-characterized collection of 53 fully-sequenced strains that represent the C. trachomatis serovars associated with the three disease groups: ocular (N=8), epithelial-genital (N=25) and lymphogranuloma venereum (LGV) (N=20). We observed that PmpF and PmpE are highly polymorphic between LGV and epithelial-genital strains, and also within populations of the latter. We also found heterogeneous representation among strains for GGA(I, L)/FxxN motifs and cysteine residues, suggesting possible alterations in adhesion properties, tissue specificity and immunogenicity. PmpG and, to a lesser extent, PmpH revealed low polymorphism and high conservation of protein features among the genital strains (including the LGV group). Uniquely among the four Pmps, pmpG has regulatory sequences suggestive of phase variation. In aggregate, the results suggest that PmpG may be the lead vaccine candidate because of sequence conservation but may need to be paired with another protective antigen (like PmpH) in order to prevent immune selection of phase variants.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas de la Membrana Bacteriana Externa/genética , Chlamydia trachomatis/genética , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Antígenos Bacterianos/química , Antígenos Bacterianos/inmunología , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/inmunología , Chlamydia trachomatis/inmunología , Chlamydia trachomatis/metabolismo , Epítopos/química , Epítopos/genética , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple
20.
Genome Announc ; 3(1)2015 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-25657274

RESUMEN

We present draft genome sequences of 10 Helicobacter pylori clinical strains isolated from children. This will be important for future studies of comparative genomics in order to better understand the virulence determinants underlying peptic ulcer disease.

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