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1.
J Surg Oncol ; 2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39099211

RESUMO

Gastrointestinal stromal tumors (GISTs) are sarcomas affecting the stomach and small intestine, with a rare subtype characterized by succinate dehydrogenase B (SDHB)-loss posing significant diagnostic and therapeutic challenges. A 62-year-old man with weight loss and abdominal pain was diagnosed with a gastric GIST showing SDHB-loss. Initial treatment with Imatinib reduced the tumor size, but surgery revealed no residual tumor. Despite adjuvant Imatinib, recurrence occurred, necessitating further surgical intervention. While GISTs typically benefit from surgery and tyrosine kinase inhibitors (TKIs), those with SDHB-loss are resistant to TKIs, requiring a different management approach. This case emphasizes the importance of surgical intervention for SDHB-deficient GISTs and the need for ongoing research into effective treatments for this subtype.

2.
Am J Otolaryngol ; 45(4): 104314, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38663327

RESUMO

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.


Assuntos
Endoscopia , Neoplasias do Seio Maxilar , Seio Maxilar , Humanos , Masculino , Feminino , Endoscopia/métodos , Estudos Retrospectivos , Pessoa de Meia-Idade , Neoplasias do Seio Maxilar/cirurgia , Seio Maxilar/cirurgia , Idoso , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Adulto , Resultado do Tratamento , Epistaxe/etiologia , Epistaxe/cirurgia , Estudos de Coortes , Parestesia/etiologia
3.
Behav Sci Law ; 42(4): 313-337, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635450

RESUMO

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.


Assuntos
Psicologia Forense , Delitos Sexuais , Humanos , Adolescente , Delitos Sexuais/psicologia , Vítimas de Crime/psicologia , Abuso Sexual na Infância/psicologia , Internet , Tecnologia
4.
Pathobiology ; 90(5): 333-343, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37040716

RESUMO

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.
Emerg Infect Dis ; 28(2): 331-337, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34876242

RESUMO

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.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , SARS-CoV-2 , Vacinação , Vacinas Sintéticas , Vacinas de mRNA
6.
Euro Surveill ; 26(10)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33706862

RESUMO

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.


Assuntos
COVID-19/virologia , SARS-CoV-2/genética , COVID-19/transmissão , Humanos , Portugal/epidemiologia , Glicoproteína da Espícula de Coronavírus/genética
7.
Antimicrob Agents Chemother ; 60(6): 3323-32, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26976875

RESUMO

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.


Assuntos
Anti-Infecciosos/farmacologia , Chlamydia trachomatis/efeitos dos fármacos , Gonorreia/tratamento farmacológico , Compostos de Amônio Quaternário/farmacologia , Streptococcus/efeitos dos fármacos , Tensoativos/farmacologia , Células HeLa , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Neisseria gonorrhoeae/efeitos dos fármacos , Infecções Sexualmente Transmissíveis/microbiologia
8.
J Antimicrob Chemother ; 71(3): 641-54, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26679255

RESUMO

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.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Tensoativos/química , Tensoativos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos Locais/química , Anti-Infecciosos Locais/farmacologia , Anti-Infecciosos Locais/uso terapêutico , Divisão Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Humanos , Metabolismo/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/fisiologia , Compostos de Amônio Quaternário/uso terapêutico , Tensoativos/uso terapêutico
10.
Trauma Violence Abuse ; 25(2): 1382-1396, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-37272340

RESUMO

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.


Assuntos
Abuso Sexual na Infância , Maus-Tratos Infantis , Criança , Humanos , Aplicação da Lei , Revisões Sistemáticas como Assunto
11.
J Bacteriol ; 194(22): 6143-53, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22961851

RESUMO

On behalf of the host-pathogen "arms race," a cutting-edge approach for elucidating genotype-phenotype relationships relies on the identification of positively selected loci involved in pathoadaptation. We studied the obligate intracellular bacterium Chlamydia trachomatis, for which same-species strains display a nearly identical core and pan genome, while presenting a wide range of tissue tropism and ecological success. We sought to evaluate the evolutionary patterns underlying species separation (divergence) and C. trachomatis serovar radiation (polymorphism) and to establish genotype-phenotype associations. By analyzing 60 Chlamydia strains, we detected traces of Muller's ratchet as a result of speciation and identified positively selected genes and codons hypothetically involved in the infection of different human cell types (e.g., columnar epithelial cells of ocular or genital mucosae and mononuclear phagocytes) and also events likely driving pathogenic and ecological success dissimilarities. In general, these genes code for proteins involved in immune response elicitation, proteolysis, and the subversion of host-cell functions, and also for proteins with unknown function(s). Several genes are potentially involved in more than one adaptive process, suggesting multiple functions or a distinct modus operandi for a specific function, and thus should be considered as crucial research targets. In addition, six of the nine genes encoding the putative antigen/adhesin polymorphic membrane proteins seem to be under positive selection along specific serovars, which sustains an essential biological role of this extra-large paralogue family in chlamydial pathobiology. This study provides insight into how evolutionary inferences illuminate ecological processes such as adaptation to different niches, pathogenicity, or ecological success driven by arms races.


Assuntos
Adaptação Fisiológica/genética , Evolução Biológica , Chlamydia trachomatis/genética , Chlamydia trachomatis/metabolismo , Infecções por Chlamydia/microbiologia , Mapeamento Cromossômico , Cromossomos Bacterianos , Regulação Bacteriana da Expressão Gênica/fisiologia , Variação Genética , Genoma Bacteriano , Interações Hospedeiro-Patógeno , Humanos , Leucócitos Mononucleares/microbiologia , Mucosa/citologia , Mucosa/microbiologia , Seleção Genética
12.
J Infect ; 85(1): 64-74, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35609706

RESUMO

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.


Assuntos
COVID-19 , COVID-19/epidemiologia , Surtos de Doenças , Genoma Viral , Genômica , Humanos , SARS-CoV-2/genética
13.
Int J Infect Dis ; 112: 318-320, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34547489

RESUMO

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.


Assuntos
COVID-19 , SARS-CoV-2 , Atenção à Saúde , Genoma Viral , Humanos , Alta do Paciente
14.
Sex Transm Infect ; 86(6): 449-53, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20940158

RESUMO

OBJECTIVES: To determine the antibiotic phenotype and MAST-genotype distribution of Neisseria gonorrhoeae isolates in Portugal between 2004 and 2009, and to evaluate specific associations between MAST-genotypes and sexual orientation, age and antibiotic resistance. METHODS: A total of 236 N gonorrhoeae isolates were typed through N gonorrhoeae multiantigen sequence typing (NG-MAST). The degree of polymorphism and the phylogenetic relatedness among NG-MAST sequence types (STs) were evaluated with MEGA4 software on concatenated sequences of por and tbpb alleles. Etest was used to determine the susceptibility to ceftriaxone, ciprofloxacin, penicillin and spectinomycin. RESULTS: No isolates displayed resistance to spectinomycin and ceftriaxone, whereas 79.1% and 37.4% were resistant to penicillin and ciprofloxacin, respectively. A total of 104 different STs (one per 2.3 isolates) were found; the most common were ST210 (8.1%) and ST225 (7.6%). STs formed two major groups separated by 159.8 (SE 8.9) nucleotide differences, yielding several subgroups, one of them including the worldwide-prevalent ST225. The probability of ciprofloxacin resistance among isolates within this subgroup was 73.5-fold higher than for the remaining isolates. Indeed, for the genetically closest subgroup, which includes the most prevalent ST (ST210), only 8.0% of isolates were resistant to ciprofloxacin. There was a non-homogeneous distribution per year for ST225 (p<0.001), ST210 (p=0.011) and ST2 (p=0.007). CONCLUSIONS: The heterogeneous ST scenario may represent the 'tip of the iceberg', reflecting a high number of undiagnosed and unreported gonorrhoea cases. A laboratory-based national surveillance of N gonorrhoeae infections is necessary to provide a broader spectrum of isolates that will allow the sexual network situation in Portugal to be established.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Gonorreia/tratamento farmacológico , Neisseria gonorrhoeae/genética , Adolescente , Adulto , Antígenos de Bactérias/genética , Técnicas de Tipagem Bacteriana , Criança , Pré-Escolar , Feminino , Gonorreia/epidemiologia , Heterossexualidade , Homossexualidade Masculina , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Neisseria gonorrhoeae/efeitos dos fármacos , Fenótipo , Polimorfismo Genético , Portugal/epidemiologia , Adulto Jovem
15.
Int J Neural Syst ; 30(5): 2050023, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32380924

RESUMO

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.


Assuntos
Aprendizado de Máquina , Modelos Teóricos , Reconhecimento Automatizado de Padrão , Humanos , Análise de Regressão
16.
IEEE Trans Neural Netw Learn Syst ; 31(10): 4389-4393, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31831445

RESUMO

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.

17.
J Bacteriol ; 191(23): 7182-92, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19783629

RESUMO

Chlamydia trachomatis is the trachoma agent and causes most bacterial sexually transmitted infections worldwide. Its major outer membrane protein (MOMP) is a well-known porin and adhesin and is the dominant antigen. So far, investigation of MOMP variability has been focused mainly on molecular epidemiological surveys. In contrast, we aimed to evaluate the impact of the host pressure on this key antigen by analyzing its evolutionary dynamics in 795 isolates from urogenital infections, taking into account the MOMP secondary structure and the sizes/positions of antigenic regions. One-third of the specimens showed a mutational drift from the corresponding genotype, where approximately 42% of the mutations had never been described. Amino acid alterations were sixfold more frequent within B-cell epitopes than in the remaining protein (P = 0.027), and some mutations were also found within or close to T-cell antigenic clusters. Interestingly, the two most ecologically successful genotypes, E and F, showed a mutation rate 60.3-fold lower than that of the other genotypes (P < 10(-8)), suggesting that their efficacy may be the result of a better fitness in dealing with the host immune system rather than of specific virulence factors. Furthermore, the variability exhibited by some genetic variants involved residues that are known to play a critical role during the membrane mechanical movements, contributing to a more stable and flexible porin conformation, which suggests some plasticity to deal with environmental pressure. Globally, these MOMP mutational trends yielded no mosaic structures or important phylogenetic changes, but instead yielded point mutations on specific protein domains, which may enhance pathogen's infectivity, persistence, and transmission.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Chlamydia trachomatis/metabolismo , Evolução Molecular , Sequência de Aminoácidos , Antígenos de Bactérias/química , Antígenos de Bactérias/classificação , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/classificação , Proteínas da Membrana Bacteriana Externa/genética , Chlamydia trachomatis/genética , Biologia Computacional , Genômica , Genótipo , Dados de Sequência Molecular , Filogenia , Homologia de Sequência de Aminoácidos
18.
Emerg Infect Dis ; 15(9): 1385-94, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19788805

RESUMO

Chlamydia trachomatis is a global cause of blinding trachoma and sexually transmitted infections (STIs). We used comparative genomics of the family Chlamydiaceae to select conserved housekeeping genes for C. trachomatis multilocus sequencing, characterizing 19 reference and 68 clinical isolates from 6 continental/subcontinental regions. There were 44 sequence types (ST). Identical STs for STI isolates were recovered from different regions, whereas STs for trachoma isolates were restricted by continent. Twenty-nine of 52 alleles had nonuniform distributions of frequencies across regions (p<0.001). Phylogenetic analysis showed 3 disease clusters: invasive lymphogranuloma venereum strains, globally prevalent noninvasive STI strains (ompA genotypes D/Da, E, and F), and nonprevalent STI strains with a trachoma subcluster. Recombinant strains were observed among STI clusters. Single nucleotide polymorphisms (SNPs) were predictive of disease specificity. Multilocus and SNP typing can now be used to detect diverse and emerging C. trachomatis strains for epidemiologic and evolutionary studies of trachoma and STI populations worldwide.


Assuntos
Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/classificação , Doenças Transmissíveis Emergentes/microbiologia , Linfogranuloma Venéreo/microbiologia , Tracoma/microbiologia , Infecções por Chlamydia/patologia , Chlamydia trachomatis/genética , Chlamydia trachomatis/isolamento & purificação , Doenças Transmissíveis Emergentes/patologia , DNA Bacteriano/análise , Genômica , Humanos , Linfogranuloma Venéreo/patologia , Fenótipo , Filogenia , Polimorfismo de Nucleotídeo Único , Valor Preditivo dos Testes , Recombinação Genética , Análise de Sequência de DNA , Infecções Sexualmente Transmissíveis/microbiologia , Infecções Sexualmente Transmissíveis/patologia , Especificidade da Espécie , Tracoma/patologia
19.
Front Microbiol ; 10: 831, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31130921

RESUMO

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.

20.
Microorganisms ; 5(2)2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28368366

RESUMO

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.

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