RESUMO
Detecting the association of genetic variants to the response of biological therapy represents an important advance in developing a personalized therapy. The aim of this work was to study the association of polymorphisms with an optimal response to tildrakizumab in patients with psoriasis in a real-life clinical practice. Ninety patients with plaque psoriasis recruited from-Spanish hospitals receiving tildrakizumab for at least 24 weeks were genotyped for 180 polymorphisms. Optimal response to tildrakizumab was evaluated by absolute PASI ≤1 at 6 and 12 months. Polymorphisms corrected for weight and disease duration with an FDR <0.15 were included in a multiple regression model. Sixty three percent of patients achieved an absolute PASI ≤1 at 6 months, while 71% did so after 12 months. Disease duration (>27 years) and weight (>76 kg) were associated with treatment response; after correcting by these factors, no association (FDR >0.15) was found for any polymorphism and response to tildrakizumab at 6 months. The analysis at 12 months identified the genotype GG for rs610604 (TNFAIP3), CT for rs9373839 (ATG5), and delCTGT/delCTGT for rs72167053 (PDE4D) as risk factors to not achieve an optimal response (PASI ≤1), while CT for rs708567 (IL17RC) was protective, independently of weight and disease duration (FDR <0.15). The final multivariable model at 12 months showed an AUC of 0.90 (95% CI 0.82 to -0.98). We identified a set of polymorphisms that could be helpful to identify psoriatic patients with an optimal response to tildrakizumab at 12 months in real-world practice conditions.
Assuntos
Anticorpos Monoclonais Humanizados , Psoríase , Humanos , Psoríase/tratamento farmacológico , Psoríase/genética , Feminino , Masculino , Pessoa de Meia-Idade , Anticorpos Monoclonais Humanizados/uso terapêutico , Adulto , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Genótipo , Idoso , Polimorfismo GenéticoRESUMO
AIM: The antifungal activity was studied on sessile and persister cells (PCs) of Candida tropicalis biofilms of gold nanoparticles (AuNPs) stabilized with cetyltrimethylammonium bromide (CTAB-AuNPs) and those conjugated with cysteine, in combination with Amphotericin B (AmB). MATERIALS/METHODS: The PC model was used and synergistic activity was tested by the checkerboard assay. Biofilms were studied by crystal violet and scanning electron microscopy. RESULTS/CONCLUSIONS: After the combination of both AuNPs and AmB the biofilm biomass was reduced, with significant differences in architecture being observed with a reduced biofilm matrix. In addition, the CTAB-AuNPs-AmB combination significantly reduced PCs. Understanding how these AuNPs aid in the fight against biofilms and the development of new approaches to eradicate PCs has relevance for chronic infection treatment.
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Anfotericina B , Antifúngicos , Biofilmes , Candida tropicalis , Sinergismo Farmacológico , Ouro , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Candida tropicalis/efeitos dos fármacos , Ouro/química , Ouro/farmacologia , Biofilmes/efeitos dos fármacos , Anfotericina B/farmacologia , Anfotericina B/química , Nanopartículas Metálicas/química , Antifúngicos/farmacologia , Antifúngicos/química , Cetrimônio/química , Compostos de Cetrimônio/farmacologia , Compostos de Cetrimônio/químicaRESUMO
BACKGROUND: Prediction of the response to a biological treatment in psoriasis patients would allow efficient treatment allocation. OBJECTIVE: To identify polymorphisms associated with secukinumab response in psoriasis patients in a daily practice setting. METHODS: We studied 180 SNPs in patients with moderate-to-severe plaque psoriasis recruited from 15 Spanish hospitals. Treatment effectiveness was evaluated by absolute PASI ≤3 and ≤1 at 6 and 12 months. Individuals were genotyped using a custom Taqman array. Multiple logistic regression models were generated. Sensitivity, specificity and area under the curve (AUC) were analysed. RESULTS: A total of 173 patients were studied at 6 months, (67% achieved absolute PASI ≤ 3 and 65% PASI ≤ 1) and 162 at 12 months (75% achieved absolute PASI ≤ 3 and 64% PASI ≤ 1). Multivariable analysis showed the association of different sets of SNPs with the response to secukinumab. The model of absolute PASI≤3 at 6 months showed best values of sensitivity and specificity. Four SNPs were associated with the capability of achieving absolute PASI ≤ 3 at 6 months. rs1801274 (FCGR2A), rs2431697 (miR-146a) and rs10484554 (HLCw6) were identified as risk factors for failure to achieve absolute PASI≤3, while rs1051738 (PDE4A) was protective. AUC including these genotypes, weight of patients and history of biological therapy was 0.88 (95% CI 0.83-0.94), with a sensitivity of 48.6% and specificity of 95.7% to discriminate between both phenotypes. CONCLUSION: We have identified a series of polymorphisms associated with the response to secukinumab capable of predicting the potential response/non-response to this drug in patients with plaque psoriasis.
Assuntos
Anticorpos Monoclonais Humanizados , Polimorfismo de Nucleotídeo Único , Psoríase , Humanos , Psoríase/tratamento farmacológico , Psoríase/genética , Feminino , Masculino , Anticorpos Monoclonais Humanizados/uso terapêutico , Pessoa de Meia-Idade , Adulto , Fármacos Dermatológicos/uso terapêutico , MicroRNAs/genética , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
BACKGROUND: Ringworm is highly prevalent in our setting and is frequently observed in our routine clinical practice. Diagnostic confirmation depends on techniques that are not always accessible (PCR), with highly variable sensitivity depending on the observer (direct microscopy) or delayed results (culture, histopathology). Recently, an immunochromatography-based rapid test (Diafactory®) for the antigenic detection of dermatophytes has been developed. This diagnostic tool can help diagnose ringworm, allowing early initiation of treatment and fewer consultation visits. OBJECTIVE: To determine the sensitivity and specificity of the rapid antigen detection test compared to conventional culture. MATERIAL AND METHODS: For a full year, 333 nail samples were collected from patients with suspected onychomycosis. The rapid test and the conventional culture were simultaneously performed on each sample. Those with a positive antigenic test result began treatment early. The remaining patients had appointments for serial cultures and subsequent medical consultation to evaluate the results. RESULTS: Compared to conventional culture, the sensitivity and specificity rates of the rapid antigen detection test are 97.2% and 80.7%, respectively. CONCLUSION: The effectiveness of the rapid antigen detection test is similar to that of conventional culture for the detection of dermatophytes in nail samples. It is a quick and simple diagnostic technique that reduces the number of patient visits to the hospital, and allows early treatment start.
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Green periurban residential areas in Mediterranean countries have flourished in the last decades and become foci for leishmaniasis. To remedy the absence of information on vector ecology in these environments, we examined phlebotomine sand fly distribution in 29 sites in Murcia City over a 3-year period, including the plots of 20 detached houses and nine non-urbanized sites nearby. We collected 5,066 specimens from five species using "sticky" interception and light attraction traps. The relative frequency of the main Leishmania infantum vector Phlebotomus perniciosus in these traps was 32% and 63%, respectively. Sand fly density was widely variable spatially and temporally and greatest in non-urbanized sites, particularly in caves and abandoned buildings close to domestic animal holdings. Phlebotomus perniciosus density in house plots was positively correlated with those in non-urbanized sites, greatest in larger properties with extensive vegetation and non-permanently lived, but not associated to dog presence or a history of canine leishmaniasis. Within house plots, sand fly density was highest in traps closest to walls. Furthermore, the study provides a guideline for insect density assessment and reporting and is envisioned as a building block towards the development of a pan-European database for robust investigation of environmental determinants of sand fly distribution.
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Leishmania infantum , Leishmaniose , Phlebotomus , Psychodidae , Animais , Cães , Feminino , Insetos Vetores , Leishmaniose/epidemiologia , Leishmaniose/veterinária , Masculino , EspanhaRESUMO
The objective of this study was to determine whether individuals with different attachment styles held different prosocial values and attitudes given their different models of self and of others. A sample of 717 university students completed the ECR-S (Experiences in Close Relationships-Spanish) and the PVQ (Portrait Values Questionnaire), and evaluated different prosocial attitudes. The results showed that secure individuals reported higher scores on self-transcendence and in the value self-directions of the dimension openness to change, whereas insecure individuals had higher scores on conservation and self-enhancement. No differences were found in the attitudes of individuals with different attachment styles. These findings show a link between the dimensions of the universal values theory, and the models of self and of others.
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Atitude , Apego ao Objeto , Comportamento Social , Valores Sociais , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The RPB1 mutants in the foot region of RNA polymerase II affect the assembly of the complex by altering the correct association of both the Rpb6 and the Rpb4/7 dimer. Assembly defects alter both transcriptional activity as well as the amount of enzyme associated with genes. Here, we show that the global transcriptional analysis of foot mutants reveals the activation of an environmental stress response (ESR), which occurs at a permissive temperature under optimal growth conditions. Our data indicate that the ESR that occurs in foot mutants depends mostly on a global post-transcriptional regulation mechanism which, in turn, depends on Rpb4-mRNA imprinting. Under optimal growth conditions, we propose that Rpb4 serves as a key to globally modulate mRNA stability as well as to coordinate transcription and decay. Overall, our results imply that post-transcriptional regulation plays a major role in controlling the ESR at both the transcription and mRNA decay levels.
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RNA Polimerase II/genética , Proteínas de Saccharomyces cerevisiae/genética , Estresse Fisiológico/genética , Transcrição Gênica , Impressão Molecular , Mutação , Estabilidade de RNA/genética , RNA Mensageiro/genética , Saccharomyces cerevisiaeRESUMO
NFIL3 is a transcription factor that regulates multiple immunologic functions. In myeloid cells, NFIL3 is IL-10 inducible and has a key role as a repressor of IL-12p40 transcription. NFIL3 is a susceptibility gene for the human inflammatory bowel diseases. In this article, we describe spontaneous colitis in Nfil3(-/-) mice. Mice lacking both Nfil3 and Il10 had severe early-onset colitis, suggesting that NFIL3 and IL-10 independently regulate mucosal homeostasis. Lymphocytes were necessary for colitis, because Nfil3/Rag1 double-knockout mice were protected from disease. However, Nfil3/Rag1 double-knockout mice adoptively transferred with wild-type CD4(+) T cells developed severe colitis compared with Rag1(-/-) recipients, suggesting that colitis was linked to defects in innate immune cells. Colitis was abrogated in Nfil3/Il12b double-deficient mice, identifying Il12b dysregulation as a central pathogenic event. Finally, germ-free Nfil3(-/-) mice do not develop colonic inflammation. Thus, NFIL3 is a microbiota-dependent, IL-10-independent regulator of mucosal homeostasis via IL-12p40.
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Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/microbiologia , Interleucina-10/genética , Subunidade p40 da Interleucina-12/metabolismo , Subunidade p19 da Interleucina-23/metabolismo , Microbiota/imunologia , Transferência Adotiva , Animais , Proteínas de Arabidopsis/biossíntese , Fatores de Transcrição de Zíper de Leucina Básica/genética , Células Cultivadas , Colo/imunologia , Colo/patologia , Predisposição Genética para Doença , Subunidade p40 da Interleucina-12/genética , Subunidade p19 da Interleucina-23/genética , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Th1/imunologia , Células Th17/imunologia , Fator de Necrose Tumoral alfa/genéticaRESUMO
Total and specific immunoglobulin (Ig) E can be detected in vitro using several commercially available methods. The largest share of the global market for these methods is held by the ImmunoCAP technique (Thermo Fisher, previously Phadia), Immulite (Siemens), and Hytec-288 (Hycor). Most comparative studies examine Immulite and ImmunoCAP, which differ methodologically but use similar units of measurement relative to the same standard of total IgE (WHO IgE Standard 75/502). Despite their similarity, these kits differ in their quantification of specific IgE, which varies depending on the allergen studied.Thus, specific IgE results obtained with ImmunoCAP and Immulite are not interchangeable. It is important to bear this in mind, especially when determining cutoff points as predictors of a response to oral challenge with specific food allergens. The method used in practice must be the same as the one in the publication guiding clinical decision making. We analyze differences between ImmunoCAP and ISAC microarray, 2 methods from the same manufacturer used to detect IgE to specific proteins (purified or recombinant).The results show that the IgE values obtained with ImmunoCAP are not equivalent to the corresponding values obtained with the ISAC microarray system.
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Imunoglobulina E/análise , Animais , Humanos , Análise Serial de Proteínas , Kit de Reagentes para DiagnósticoRESUMO
Persistence of the human immunodeficiency virus type-1 (HIV-1) latent reservoir in infected individuals remains a problem despite fully suppressive antiretroviral therapy (ART). While reservoir formation begins during acute infection, the mechanisms responsible for its establishment remain unclear. CD8+ T cells are important during the initial control of viral replication. Here we examined the effect of CD8+ T cells on formation of the latent reservoir in simian immunodeficiency virus (SIV)-infected macaques by performing experimental CD8+ depletion either before infection or before early (that is, day 14 post-infection) ART initiation. We found that CD8+ depletion resulted in slower decline of viremia, indicating that CD8+ lymphocytes reduce the average lifespan of productively infected cells during acute infection and early ART, presumably through SIV-specific cytotoxic T lymphocyte (CTL) activity. However, CD8+ depletion did not change the frequency of infected CD4+ T cells in the blood or lymph node as measured by the total cell-associated viral DNA or intact provirus DNA assay. In addition, the size of the persistent reservoir remained the same when measuring the kinetics of virus rebound after ART interruption. These data indicate that during early SIV infection, the viral reservoir that persists under ART is established largely independent of CTL control.
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Infecções por HIV , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Humanos , Vírus da Imunodeficiência Símia/genética , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Linfócitos T CD8-Positivos , Antirretrovirais/uso terapêutico , Macaca mulatta , Infecções por HIV/tratamento farmacológicoRESUMO
INTRODUCTION: Terson syndrome (TS) is defined as any intraocular haemorrhage identified in patients with acute intracranial pathology. TS appears to be associated with clinical severity in patients with subarachnoid haemorrhage (SAH), but the association is yet to be defined in patients with traumatic brain injury (TBI) and intracerebral haemorrhage (ICH). This study aimed to evaluate the diagnostic performance of ocular ultrasound (OU) and its usefulness in clinical practice. MATERIAL AND METHODS: We performed an observational, prospective, single-centre study of neurocritical care patients. We analysed cases and controls, defined according to indirect ophthalmoscopy (IO) and OU findings. We determined the diagnostic characteristics of OU. A multivariate analysis was performed to identify clinically relevant associations. RESULTS: The sample included 91 patients diagnosed with ICH (41.76%), SAH (29.67%), and TBI (28.57%). TS was identified by OU in 8 patients (8.79%) and by IO in 24 (24.37%). The adjusted mortality rate in patients with TS showed an odds ratio (OR) of 4.15 (95% confidence interval [CI], 1.52-11.33). All patients with TS detected by OU presented Glasgow Coma Scale scores <â¯9, with an elevated risk of needing decompressive craniectomy (OR: 9.84; 95% CI, 1.64-59). OU presented an overall sensitivity of 30.43%, specificity of 98.53%, and diagnostic accuracy of 81.32%. For the detection of vitreous haemorrhage, sensitivity and specificity were 87.5% and 98.5%, respectively. CONCLUSIONS: OU diagnosis of TS identifies extremely critical patients, who may require the highest level of care; TS is an independent risk factor for in-hospital mortality.
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Hemorragia Subaracnóidea , Hemorragia Vítrea , Humanos , Hemorragia Cerebral , Estudos Prospectivos , Fatores de Risco , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Vítrea/diagnóstico por imagem , Hemorragia Vítrea/complicaçõesRESUMO
Research to date has revealed that the association between gender, attachment and the quality and functioning of intimate relationships is complex. This study examined the relationship between gender and attachment styles in attitudes to communication with one's partner and in the number of past relationships in a sample of 746 Spanish undergraduates. The Relationship Questionnaire was administered to them to determine the adult attachment style. The results revealed the existence of differences according to the adult attachment style and gender with regard to the two measured variables, and a significant effect of the interaction between gender and attachment. Dismissing men reported the highest average scores in the number of past relationships, with significant differences appearing when they were compared with secure and preoccupied men. However, dismissing women did not differ from the rest of the women with other attachment styles. When men and women with the same attachment styles were compared in this variable, the only significant differences were found between dismissing men and women (with the latter reporting fewer partners). In the case of attitudes to expressing feelings to one's partner, dismissing men reported the most negative attitudes, compared with secure and preoccupied men. Dismissing women, unlike the men, did not differ in their attitudes either from preoccupied or fearful women. Moreover, clear differences were shown between dismissing men and women in these attitudes (more negative in the case of men).
Assuntos
Identidade de Gênero , Relações Interpessoais , Apego ao Objeto , Adulto , Afeto , Atitude , Comunicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos de Amostragem , Espanha , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Inquéritos e QuestionáriosRESUMO
BACKGROUND: The PI3K-mTOR (phosphoinositide 3-kinase-mammalian target of rapamycin kinase) pathway is activated in the majority of tumours, and there is interest in assessing whether inhibitors of PI3K or mTOR kinase have efficacy in treating cancer. Here, we define the effectiveness of specific mTOR (AZD8055) and PI3K (GDC-0941) inhibitors, currently in clinical trials, in treating spontaneous B-cell follicular lymphoma that develops in PTEN(+/-)LKB1(+/hypo) mice. METHODS: The PTEN(+/-)LKB1(+/hypo) mice were administered AZD8055 or GDC-0941, and the volumes of B-cell follicular lymphoma were measured by MRI. Tumour samples were analysed by immunohistochemistry, immunoblot and flow cytometry. RESULTS: The AZD8055 or GDC-0941 induced â¼40% reduction in tumour volume within 2 weeks, accompanied by ablation of phosphorylation of AKT, S6K and SGK (serum and glucocorticoid protein kinase) protein kinases. The drugs reduced tumour cell proliferation, promoted apoptosis and suppressed centroblast population. The AZD8055 or GDC-0941 treatment beyond 3 weeks caused a moderate additional decrease in tumour volume, reaching â¼50% of the initial volume after 6 weeks of treatment. Tumours grew back at an increased rate and displayed similar high grade and diffuse morphology as the control untreated tumours upon cessation of drug treatment. CONCLUSION: These results define the effects that newly designed and specific mTOR and PI3K inhibitors have on a spontaneous tumour model, which may be more representative than xenograft models frequently employed to assess effectiveness of kinase inhibitors. Our data suggest that mTOR and PI3K inhibitors would benefit treatment of cancers in which the PI3K pathway is inappropriately activated; however, when administered alone, may not cause complete regression of such tumours.
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Linfoma de Células B/tratamento farmacológico , Linfoma Folicular/tratamento farmacológico , PTEN Fosfo-Hidrolase/fisiologia , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/fisiologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP , Animais , Indazóis/uso terapêutico , Linfoma de Células B/patologia , Linfoma Folicular/patologia , Camundongos , Camundongos Endogâmicos C57BL , Morfolinas/uso terapêutico , Fosfatidilinositol 3-Quinases/fisiologia , Transdução de Sinais , Sulfonamidas/uso terapêutico , Serina-Treonina Quinases TOR/fisiologiaAssuntos
Anticorpos Antibacterianos/imunologia , Formação de Anticorpos/imunologia , Síndromes de Imunodeficiência/imunologia , Polissacarídeos Bacterianos/imunologia , Salmonella typhi/imunologia , Vacinas Tíficas-Paratíficas/imunologia , Adulto , Agamaglobulinemia/imunologia , Idoso , Imunodeficiência de Variável Comum/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Salmonella typhi/fisiologia , Febre Tifoide/imunologia , Febre Tifoide/microbiologia , Febre Tifoide/prevenção & controle , Vacinas Tíficas-Paratíficas/administração & dosagem , Vacinação/métodos , Adulto JovemRESUMO
The Locus Control Region (LCR) requires intronic elements within beta-globin transgenes to direct high level expression at all ectopic integration sites. However, these essential intronic elements cannot be transmitted through retrovirus vectors and their deletion may compromise the therapeutic potential for gene therapy. Here, we systematically regenerate functional beta-globin intron 2 elements that rescue LCR activity directed by 5'HS3. Evaluation in transgenic mice demonstrates that an Oct-1 binding site and an enhancer in the intron cooperate to increase expression levels from LCR globin transgenes. Replacement of the intronic AT-rich region with the Igmu 3'MAR rescues LCR activity in single copy transgenic mice. Importantly, a combination of the Oct-1 site, Igmu 3'MAR and intronic enhancer in the BGT158 cassette directs more consistent levels of expression in transgenic mice. By introducing intron-modified transgenes into the same genomic integration site in erythroid cells, we show that BGT158 has the greatest transcriptional induction. 3D DNA FISH establishes that induction stimulates this small 5'HS3 containing transgene and the endogenous locus to spatially reorganize towards more central locations in erythroid nuclei. Electron Spectroscopic Imaging (ESI) of chromatin fibers demonstrates that ultrastructural heterochromatin is primarily perinuclear and does not reorganize. Finally, we transmit intron-modified globin transgenes through insulated self-inactivating (SIN) lentivirus vectors into erythroid cells. We show efficient transfer and robust mRNA and protein expression by the BGT158 vector, and virus titer improvements mediated by the modified intron 2 in the presence of an LCR cassette composed of 5'HS2-4. Our results have important implications for the mechanism of LCR activity at ectopic integration sites. The modified transgenes are the first to transfer intronic elements that potentiate LCR activity and are designed to facilitate correction of hemoglobinopathies using single copy vectors.
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Terapia Genética/métodos , Globinas/genética , Anemia Falciforme/genética , Anemia Falciforme/terapia , Animais , Sequência de Bases , Sítios de Ligação/genética , Linhagem Celular , Primers do DNA/genética , Elementos Facilitadores Genéticos , Feminino , Expressão Gênica , Teste de Complementação Genética , Vetores Genéticos , Íntrons , Região de Controle de Locus Gênico , Masculino , Camundongos , Camundongos Transgênicos , Fator 1 de Transcrição de Octâmero/metabolismo , Gravidez , Proteínas Recombinantes/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
OBJECTIVE: To analyze the different perceptions of professionals about the problem of intellectual disability in the prison setting. MATERIAL AND METHOD: Exploratory-descriptive type. In-depth interviews with legal, social and prison operators of Centro Penitenciario de Zuera (Zaragoza). RESULTS: The narratives of the interviewed subjects point to the aggravating circumstances that a closed social environment can entail for inmates with intellectual disabilities. Communications in the prison administration are written in a technical language that is not understandable for inmates with intellectual deficits. DISCUSION: There is a need to give more visibility to the case of inmates with intellectual disabilities. Procedures also need to be applied that favour greater cognitive accessibility for this profile of inmates, along with the promotion of awareness raising and training for professionals to enable them to deal with this issue.
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Deficiência Intelectual , Prisioneiros , Humanos , Prisioneiros/psicologia , PrisõesRESUMO
OBJECTIVE: Clostridioides difficile (CD) is the most common cause of nosocomial diarrhea. Detection of CD toxin in patients' faecal samples is the traditional rapid method for the diagnosis of CD infection. Various testing algorithms have been proposed: an initial screening test using a rapid test, and a confirmatory test (cytotoxicity neutralization assay, toxigenic culture, nucleic acid amplification test) for discordant results. The aim of this study was to evaluate the effectiveness of a two-step algorithm using an immunochromatographic test followed of a polymerase chain reaction (PCR). METHODS: The specimens have been tested according to the following schedule: 1) Step one: All samples were tested for detection of glutamate dehydrogenase antigen (GDH) and toxin A/B using the C. diff QUIK CHEK Complete test. All GDH and toxins positive results were considered CD positives; 2) Step two: When the results were discrepant (only GDH+ or toxins+), the samples were confirmed using the PCR test BD MAX Cdiff. All PCR positive results were considered CD positives. RESULTS: A total of 2,138 specimens were initially tested. 139 were positive for GDH and toxins. 160 discrepant results (148 GDH+ and 12 toxins+) were tested by PCR, 117 were positive (107/148 GDH+ and 10/12 toxins+). CONCLUSIONS: The implementation of a PCR method showed an increase de 117 positive results (73.1% of discrepant). Considering the sensitivity of C.diff QUIK CHEK (instructions of manufacturer), the GDH discrepant results may be false negatives, y the samples PCR and toxins positives may be real positives results.
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Toxinas Bacterianas , Clostridioides difficile , Infecções por Clostridium , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Clostridioides , Clostridioides difficile/genética , Infecções por Clostridium/diagnóstico , Enterotoxinas , Fezes , Glutamato Desidrogenase/genética , Humanos , Reação em Cadeia da Polimerase , Sensibilidade e EspecificidadeRESUMO
CRISPR (clustered regularly interspaced short palindromic repeats) and CAS (CRISPR-associated sequence) proteins are constituents of a novel genetic barrier that limits horizontal gene transfer in prokaryotes by means of an uncharacterized mechanism. The fundamental discovery of small RNAs as the guides of the defence apparatus arose as a result of Escherichia coli studies. However, a survey of the system diversity in this species in order to further contribute to the understanding of the CRISPR mode of action has not yet been performed. Here we describe two CRISPR/CAS systems found in E. coli, following the analysis of 100 strains representative of the species' diversity. Our results substantiate different levels of activity between loci of both CRISPR types, as well as different target preferences and CRISPR relevances for particular groups of strains. Interestingly, the data suggest that the degeneration of one CRISPR/CAS system in E. coli ancestors could have been brought about by self-interference.