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1.
Artículo en Inglés | MEDLINE | ID: mdl-39174387

RESUMEN

INTRODUCTION: Colorectal cancer (CRC) is the third-most common cancer diagnosed worldwide, with 1.85 million new cases per year. While mortality has significantly decreased due to preventive colonoscopy, only 5% of polyps identified progress to cancer. Studies have found that immunological alterations in other solid tumor microenvironments are associated with worse prognoses. METHODS: We applied an immunogenomics approach to assess adaptive immune receptor gene expression changes that were associated with development of adenocarcinoma, utilizing 79 samples that represented normal, tubular, villous, and tumor colorectal tissue for 32 patients. RESULTS: Results indicated that the number of productive TRD and TRG recombination reads, representing gamma-delta (γδ) T-cells, significantly decreased with progression from normal to tumor tissue. A further assessment of two independent CRC datasets was consistent with a decrease in TRD recombination reads with progression to CRC. Further, we identified three physicochemical parameters for immunoglobulin, complementarity determining region-3 (CDR3) amino acids associated with progression from normal to tumor tissue. CONCLUSIONS: Overall, this study points towards a need for further investigation of γδ T-cells in relation to CRC development; and indicates immunoglobulin CDR3 physicochemical features as potential CRC biomarkers.

2.
Cancer Genomics Proteomics ; 21(5): 439-447, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39191494

RESUMEN

BACKGROUND/AIM: Wilms' tumors are pediatric renal tumors that generally have a good prognosis and outcomes. Viral illnesses have been linked to development of neoplasms and should be considered as a factor that could modulate overall survival. MATERIALS AND METHODS: We considered recently developed adaptive immune receptor, genomics and bioinformatics approaches to assess the potential impact of cytomegalovirus (CMV) infections in Wilms' tumor. RESULTS: T-cell receptor (TCR) complementarity determining region-3 (CDR3) amino acid sequences from Wilms' tumor specimens represented by the Therapeutically Applicable Research to Generate Effective Treatments dataset were compared with known anti-CMV TCR CDR3s, indicating that cases representing the anti-CMV TCR CDR3s had worse outcomes. Then, a chemical complementarity scoring approach for the Wilms' tumor, TCR CDR3s and a series of CMV antigens further indicated that cases representing a higher chemical complementarity to the CMV antigens had worse outcomes. CONCLUSION: Overall, we present a potentially novel method to assess CMV infections and identify patients who could benefit from therapies that address such infections.


Asunto(s)
Regiones Determinantes de Complementariedad , Citomegalovirus , Neoplasias Renales , Receptores de Antígenos de Linfocitos T , Tumor de Wilms , Humanos , Tumor de Wilms/inmunología , Tumor de Wilms/genética , Regiones Determinantes de Complementariedad/genética , Regiones Determinantes de Complementariedad/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Neoplasias Renales/inmunología , Neoplasias Renales/genética , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Pronóstico , Epítopos/inmunología
3.
Viral Immunol ; 37(5): 259-265, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38848306

RESUMEN

Cytomegalovirus (CMV) has long been thought to have an association with glioblastoma multiforme (GBM), although the exact role of CMV and any subsequent implications for treatment have yet to be fully understood. This study addressed whether IGH complementarity determining region-3 (CDR3)-CMV protein chemical complementarity, with IGH CDR3s representing both tumor resident and blood-sourced IGH recombinations, was associated with overall survival (OS) distinctions. IGH recombination sequencing reads were obtained from (a) the Clinical Proteomic Tumor Analysis Consortium, tumor RNAseq files; and (b) the cancer genome atlas, blood exome-derived files. The Adaptive Match web tool was used to calculate chemical complementarity scores (CSs) based on hydrophobic interactions, and those scores were used to group GBM cases and assess survival probabilities. We found a higher OS probability for cases whose hydrophobic IGH CDR3-CMV protein chemical complementarity scores (Hydro CSs) were in the upper 50th percentile for several CMV proteins, including UL99 and UL123, as well as for CSs based on known B cell epitopes representing these proteins. We also identified multiple immune signature genes, including CD79A and TNFRSF17, for which higher RNA expression was associated with higher Hydro CSs. Results were consistent with the idea that stronger immunoglobulin responses to CMV are associated with better OS probabilities for GBM.


Asunto(s)
Regiones Determinantes de Complementariedad , Infecciones por Citomegalovirus , Citomegalovirus , Glioblastoma , Proteínas Virales , Humanos , Glioblastoma/mortalidad , Glioblastoma/genética , Glioblastoma/virología , Citomegalovirus/genética , Citomegalovirus/inmunología , Regiones Determinantes de Complementariedad/genética , Regiones Determinantes de Complementariedad/inmunología , Infecciones por Citomegalovirus/mortalidad , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Proteínas Virales/genética , Proteínas Virales/inmunología , Cadenas Pesadas de Inmunoglobulina/genética , Femenino , Persona de Mediana Edad , Masculino , Análisis de Supervivencia , Anciano , Epítopos de Linfocito B/inmunología , Epítopos de Linfocito B/genética
4.
Anticancer Res ; 44(4): 1505-1511, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537966

RESUMEN

BACKGROUND/AIM: Due to still unresolved questions regarding viruses as either a primary cause or a comorbidity in cancer, we examined a potential immune response to cytomegalovirus (CMV) in the renal cell carcinoma (RCC) setting using genomics and bioinformatics approaches. MATERIALS AND METHODS: Specifically, we assessed chemical complementarity scores (CSs) for solid tissue normal resident, T-cell receptor (TCR) complementarity determining region 3 (CDR3s) and CMV antigens and determined whether higher or lower CS groups were associated with a higher or lower survival probability. RESULTS: This was indeed the case, with all such analyses consistently indicating a lower overall and progression-free survival for the cases representing the higher TCR CDR3-CMV antigen chemical CSs. This basic result was obtained for two separate RCC datasets and multiple CMV antigens. CONCLUSION: The results raise the question, to what extent a systemic CMV infection may represent an important co-morbidity for RCC.


Asunto(s)
Carcinoma de Células Renales , Infecciones por Citomegalovirus , Neoplasias Renales , Humanos , Carcinoma de Células Renales/complicaciones , Receptores de Antígenos de Linfocitos T alfa-beta , Infecciones por Citomegalovirus/etiología , Citomegalovirus , Neoplasias Renales/complicaciones , Receptores de Antígenos de Linfocitos T
5.
Melanoma Res ; 34(2): 118-124, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38329217

RESUMEN

Hypoxia has established associations with aggressive tumor phenotypes in many cancers. However, it is not currently understood whether tumor hypoxia levels map to distinct immune infiltrates in cutaneous melanoma, potentially unveiling novel therapeutic targets. To this end, we leveraged a previously identified seven-gene hypoxia signature to grade hypoxia levels of 460 cutaneous melanomas obtained from the Broad Institute GDAC Firehose portal. CIBERSORTx ( https://cibersortx.stanford.edu/ ) was employed to calculate the relative abundance of 22 mature human hematopoietic populations. Clinical outcomes and immune cell associations were assessed by computational means. Results indicated that patients with high-hypoxia tumors reported significantly worse overall survival and correlated with greater Breslow depth, validating the in-silico methodology. High-hypoxia tumors demonstrated increased infiltration of activated and resting dendritic cells, resting mast cells, neutrophils, and resting NK cells, but lower infiltration of gamma-delta T cells. These data suggest that high tumor hypoxia correlates with lower survival probability and distinct population differences of several tumor-infiltrating leukocytes in cutaneous melanomas.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/genética , Neoplasias Cutáneas/genética , Transcriptoma , Hipoxia , Células Asesinas Naturales
6.
Ophthalmol Ther ; 13(1): 305-319, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37955835

RESUMEN

INTRODUCTION: The mismatch between training and testing data distribution causes significant degradation in the deep learning model performance in multi-ethnic scenarios. To reduce the performance differences between ethnic groups and image domains, we built a deep transfer learning model with adaptation training to predict uncorrected refractive errors using posterior segment optical coherence tomography (OCT) images of the macula and optic nerve. METHODS: Observational, cross-sectional, multicenter study design. We pre-trained a deep learning model on OCT images from the B&VIIT Eye Center (Seoul, South Korea) (N = 2602 eyes of 1301 patients). OCT images from Poona Eye Care (Pune, India) were chronologically sorted into adaptation training data (N = 60 eyes of 30 patients) for transfer learning and test data (N = 142 eyes of 71 patients) for validation. Deep learning models were trained to predict spherical equivalent (SE) and mean keratometry (K) values via transfer learning for domain adaptation. RESULTS: Both adaptation models for SE and K were significantly better than those without adaptation (P < 0.001). In myopia/hyperopia classification, the model trained on circular optic disc OCT images yielded the best performance (accuracy = 74.7%). It also performed best in estimating SE with the lowest mean absolute error (MAE) of 1.58 D. For classifying the degree of corneal curvature, the optic nerve vertical algorithm performed best (accuracy = 65.7%). The optic nerve horizontal model achieved the lowest MAE (1.85 D) when predicting the K value. Saliency maps frequently highlighted the retinal nerve fiber layers. CONCLUSIONS: Adaptation training via transfer learning is an effective technique for estimating refractive errors and K values using macular and optic nerve OCT images from ethnically heterogeneous populations. Further studies with larger sample sizes and various data sources are needed to confirm the feasibility of the proposed algorithm.

7.
JCO Precis Oncol ; 7: e2300057, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-38085056

RESUMEN

PURPOSE: In certain cancers, oncogene amplification is correlated with an immunologically cold or noninflamed, tumor immune microenvironment (TIME) and a worse prognosis, for example, in the case of MYCN-amplified neuroblastoma (NBL). However, for other cancer types, the relationship between oncogene amplification and immune response is more complicated or unresolved. One such cancer is glioblastoma multiforme (GBM), in which the epidermal growth factor receptor (EGFR) oncogene is commonly amplified. Unlike MYCN-amplified NBL, EGFR-amplified GBM has not been shown to correlate with a distinct survival probability. METHODS: Given this contrasting state for NBL and GBM, we sought to apply a genomics approach to evaluating the immune response for cases with gene amplification. RESULTS: Our results confirmed and added further specificity to the cold TIME of MYCN-amplified NBL. Moreover, we demonstrated a novel state of immunologically cold EGFR-amplified GBM tumors. CONCLUSION: This approach to using copy number variation and immune receptor recombination read recovery levels to assess gene amplification and TIME, respectively, may be particularly efficient for the rapid evaluation of many other cancer types.


Asunto(s)
Glioblastoma , Neuroblastoma , Humanos , Glioblastoma/genética , Variaciones en el Número de Copia de ADN/genética , Proteína Proto-Oncogénica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/metabolismo , Receptores ErbB/genética , Oncogenes , Recombinación Genética , Microambiente Tumoral/genética
8.
Viral Immunol ; 36(10): 669-677, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38052065

RESUMEN

To better understand how adaptive immune receptors (IRs) in hepatocellular carcinoma (HCC) microenvironments are related to disease outcomes, we employed a chemical complementarity scoring algorithm to quantify electrostatic complementarity between HCC tumor TRB or IGH complementarity-determining region 3 (CDR3) amino acid (AA) sequences and previously characterized hepatitis C virus (HCV) epitopes. High electrostatic complementarity between HCC-resident CDR3s and 12 HCV epitopes was associated with greater survival probabilities, as indicated by two distinct HCC IR CDR3 datasets. Two of the HCV epitopes, HCV*71871 (TRB) and HCV*13458 (IGH), were also determined to represent significantly larger electrostatic CDR3-HCV epitope complementarity in HCV-positive HCC cases, compared with HCV-negative HCC cases, with the CDR3s representing yet a third, independent HCC dataset. Overall, the results indicated the utility of CDR3 AA sequences as biomarkers for HCC patient stratification and as potential guides for the development of therapeutic reagents.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis C , Neoplasias Hepáticas , Humanos , Hepacivirus , Epítopos , Regiones Determinantes de Complementariedad/genética , Microambiente Tumoral
9.
J Med Virol ; 95(8): e29043, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37621059

RESUMEN

The liver is a site of immune privilege, compared with the bladder and skin, for example. To study this attenuation of the immune response in the cancer setting, we compared quantities and features of adaptive immune receptor (IR) recombination reads obtained from hepatocellular carcinoma (HCC) and six other cancers. Of these cancers, HCC had the lowest numbers of IR recombination reads and was the only cancer with a greater number immunoglobulin rather than T-cell receptor recombination reads. To better understand the role of adaptive IRs obtained from the tumor microenvironment in shaping the outcome of HCC cases, we quantified the chemical complementarity between HCC tumor TRB and IGH complementarity determining region-3 (CDR3) amino acid (AA) sequences, and known hepatitis B virus (HBV) epitopes. High chemical complementarity between HCC-resident CDR3s and three HBV epitopes correlated with increased survival probabilities, for two sources of CDR3s representing different CDR3 recovery algorithms. These results suggest the potential of CDR3 AA sequences as biomarkers for HCC patient stratification and as guides for future development of therapeutics.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Supervivencia sin Enfermedad , Virus de la Hepatitis B/genética , Regiones Determinantes de Complementariedad/genética , Epítopos/genética , Microambiente Tumoral
10.
Cancer Biomark ; 38(1): 103-110, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37545223

RESUMEN

BACKGROUND: Immunogenomics approaches to the characterization of renal cell carcinoma (RCC) have helped to better our understanding of the features of RCC immune dysfunction. However, much is still unknown with regard to specific immune interactions and their impact in the tumor microenvironment. OBJECTIVE: This study applied chemical complementarity scoring for the TRB complementarity determining region-3 (CDR3) amino acid sequences and cancer testis antigens (CTAs) to determine whether such complementarity correlated with survival and the expression of immune marker genes. METHODS: TRB recombination reads from RCC tumor samples from RNAseq files obtained from two separate databases, Moffitt Cancer Center and The Cancer Genome Atlas (TCGA), were evaluated. Chemical complementarity scores (CSs) were calculated for TRB CDR3-CTA pairs and survival assessments based on those CSs were performed. RESULTS: Moffitt Cancer Center and TCGA cases representing the upper 50th percentile of chemical CSs for TRB CDR3 amino acid sequences and the CTA POTEA were found to be associated with a better overall survival (OS) Also, greater tumor RNA expression of multiple immune signature genes, including granzyme A, granzyme B, and interferon-gamma were correlated with the higher chemical CSs. CONCLUSIONS: These results indicate that TRB CDR3-CTA chemical complementarity scoring may be useful in distinguishing RCC cases with a productive, anti-tumor immune response from cases where basic immune parameter assessments are inconsistent with a productive immune response.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Masculino , Humanos , Regiones Determinantes de Complementariedad/genética , Regiones Determinantes de Complementariedad/química , Carcinoma de Células Renales/genética , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Testículo/metabolismo , Neoplasias Renales/genética , Inmunidad , Microambiente Tumoral
11.
J Cancer Res Clin Oncol ; 149(13): 12047-12056, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37421457

RESUMEN

With the advent of large collections of adaptive immune receptor recombination reads representing cancer, there is the opportunity to further investigate the adaptive immune response to viruses in the cancer setting. This is a particularly important goal due to longstanding but still not well-resolved questions about viral etiologies in cancer and viral infections as comorbidities. In this report, we assessed the T cell receptor complementarity determining region-3 (CDR3) amino acid (AA) sequences, for blood-sourced TCRs from neuroblastoma (NBL) cases, for exact AA sequence matches to previously identified anti-viral TCR CDR3 AA sequences. Results indicated the presence of anti-viral TCR CDR3 AA sequences in the NBL blood samples highly significantly correlated with worse overall survival. Furthermore, the TCR CDR3 AA sequences demonstrating chemical complementarity to many cytomegalovirus antigens represented cases with a worse outcome, including cases where such CDR3s were obtained from tumor samples. Overall, these results indicate a significant need for, and provide a novel strategy for assessing viral infection complications in NBL patients.


Asunto(s)
Antivirales , Neuroblastoma , Humanos , Receptores de Antígenos de Linfocitos T , Regiones Determinantes de Complementariedad/química , Secuencia de Aminoácidos , Neuroblastoma/genética
12.
Biology (Basel) ; 12(4)2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37106775

RESUMEN

INTRODUCTION: Glioblastoma (GBM) is the most aggressive primary brain tumor in adults. Despite a growing understanding of glioblastoma pathology, the prognosis remains poor. METHODS: In this study, we used a previously extensively benchmarked algorithm to retrieve immune receptor (IR) recombination reads from GBM exome files available from the cancer genome atlas. The T-cell receptor complementarity determining region-3 (CDR3) amino acid sequences that represent the IR recombination reads were assessed and used for the generation of chemical complementarity scores (CSs) that represent potential binding interactions with cancer testis antigens (CTAs), which is an approach particularly suited to a big data setting. RESULTS: The electrostatic CSs representing the TRA and TRB CDR3s and the CTAs, SPAG9, GAGE12E, and GAGE12F, indicated that an increased electrostatic CS was associated with worse disease-free survival (DFS). We also assessed the RNA expression of immune marker genes, which indicated that a high-level expression of SPHK2 and CIITA genes also correlated with high CSs and worse DFS. Furthermore, apoptosis-related gene expression was revealed to be lower when the TCR CDR3-CTA electrostatic CSs were high. CONCLUSION: Adaptive IR recombination reads from exome files have the potential to aid in GBM prognoses and may provide opportunities to detect unproductive immune responses.

13.
J Biol Chem ; 299(4): 104599, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36907438

RESUMEN

Immune cells adopt a variety of metabolic states to support their many biological functions, which include fighting pathogens, removing tissue debris, and tissue remodeling. One of the key mediators of these metabolic changes is the transcription factor hypoxia-inducible factor 1α (HIF-1α). Single-cell dynamics have been shown to be an important determinant of cell behavior; however, despite the importance of HIF-1α, little is known about its single-cell dynamics or their effect on metabolism. To address this knowledge gap, here we optimized a HIF-1α fluorescent reporter and applied it to study single-cell dynamics. First, we showed that single cells are likely able to differentiate multiple levels of prolyl hydroxylase inhibition, a marker of metabolic change, via HIF-1α activity. We then applied a physiological stimulus known to trigger metabolic change, interferon-γ, and observed heterogeneous, oscillatory HIF-1α responses in single cells. Finally, we input these dynamics into a mathematical model of HIF-1α-regulated metabolism and discovered a profound difference between cells exhibiting high versus low HIF-1α activation. Specifically, we found cells with high HIF-1α activation are able to meaningfully reduce flux through the tricarboxylic acid cycle and show a notable increase in the NAD+/NADH ratio compared with cells displaying low HIF-1α activation. Altogether, this work demonstrates an optimized reporter for studying HIF-1α in single cells and reveals previously unknown principles of HIF-1α activation.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia , Activación Transcripcional , Animales , Ratones , Genes Reporteros/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Prolina Dioxigenasas del Factor Inducible por Hipoxia/antagonistas & inhibidores , Interferón gamma/farmacología , Mitocondrias/metabolismo , Modelos Biológicos , Prolil Hidroxilasas/metabolismo , Células RAW 264.7 , Análisis de la Célula Individual/métodos , Activación Transcripcional/efectos de los fármacos
15.
AMIA Jt Summits Transl Sci Proc ; 2022: 446-455, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35854743

RESUMEN

Unplanned readmission to the intensive care unit (ICU) confers excess morbidity and mortality. We explore whether machine learning models can outperform the current standard, the Stability and Workload Index for Transfer (SWIFT) score, in assessing 7-day ICU readmission risk at discharge. Logistic regression, random forest, support vector machine, and gradient boosting models were trained and validated on Stanford Hospital data (2009-2019), externally validated on Beth Israel Deaconess Medical Center (BIDMC) data (2008-2019) and benchmarked against SWIFT. The best performing model was gradient boosting, with AUROC of 0.85 and 0.60 and F1-score of 0.43 and 0.14 on internal and external validation, respectively. SWIFT had an AUROC of 0.67 and 0.51 and F1-score of 0.33 and 0.10 on Stanford and BIDMC data, respectively. Machine learning models predicting 7-day ICU readmission risk can improve current ICU discharge risk assessment standards, but performance may be limited without local training.

16.
Gastroenterol Res Pract ; 2016: 2313850, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27829832

RESUMEN

Hepatic stem/progenitor cells (HPC) reside quiescently in normal biliary trees and are activated in the form of ductular reactions during severe liver damage when the replicative ability of hepatocytes is inhibited. HPC niches are full of profibrotic stimuli favoring scarring and hepatocarcinogenesis. The Cyr61/CTGF/NOV (CCN) protein family consists of six members, CCN1/CYR61, CCN2/CTGF, CCN3/NOV, CCN4/WISP1, CCN5/WISP2, and CCN6/WISP3, which function as extracellular signaling modulators to mediate cell-matrix interaction during angiogenesis, wound healing, fibrosis, and tumorigenesis. This study investigated expression patterns of CCN proteins in HPC and cholangiocarcinoma (CCA). Mouse HPC were induced by the biliary toxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). Differential expression patterns of CCN proteins were found in HPC from DDC damaged mice and in human CCA tumors. In addition, we utilized reporter mice that carried Ccn2/Ctgf promoter driven GFP and detected strong Ccn2/Ctgf expression in epithelial cell adhesion molecule (EpCAM)+ HPC under normal conditions and in DDC-induced liver damage. Abundant CCN2/CTGF protein was also found in cytokeratin 19 (CK19)+ human HPC that were surrounded by α-smooth muscle actin (α-SMA)+ myofibroblast cells in intrahepatic CCA tumors. These results suggest that CCN proteins, particularly CCN2/CTGF, function in HPC activation and CCA development.

17.
J Clin Microbiol ; 51(12): 4156-60, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24108603

RESUMEN

In our jurisdiction, the Aptima Combo 2 assay (Gen-Probe, Inc.) is used to detect Neisseria gonorrhoeae from specimens collected at clinics for sexually transmitted infections (STI) and from select community patients. In addition, swabs are also collected for N. gonorrhoeae culture, susceptibility testing, and sequence typing (ST). Since only a small proportion of samples from provincial cases undergo culture, the available trends in antimicrobial susceptibility and predominant strain types may not be representative of all N. gonorrhoeae infections. Due to the limitations facing the use of N. gonorrhoeae culture to understand these trends in the general community, we performed a molecular analysis for markers of cephalosporin resistance and ST determination by using nucleic acid extracts of specimens sent for Aptima testing. Thirty-four samples submitted for both Aptima testing and N. gonorrhoeae culture from the same anatomic location (within 24 h) were included in the study. Sequence type was determined based on the sequence of the por and tbpB genes, and amino acid changes in the PBP 2 protein, encoded by the penA gene, were considered representative for the assessment of antimicrobial susceptibility. Sequence identity of 100% was observed between the sequences obtained from Aptima-analyzed samples and culture samples. Sequencing results showed an association between decreased susceptibility to extended-spectrum cephalosporins (ESC(ds)), tbp allele 110, ST 1407, and amino acid changes (G545S, I312M, and V316T) in the PBP 2 protein. Our data, generated based on a few representative genes, suggest that gonococcal samples positive by Aptima testing can be used to determine single nucleotide polymorphisms associated with ESC(ds) and the sequence type based on molecular strain typing. Confirmation of these findings may obviate the need for gonorrhea culture in the future.


Asunto(s)
Antibacterianos/farmacología , Técnicas Bacteriológicas/métodos , Farmacorresistencia Bacteriana , Técnicas de Diagnóstico Molecular/métodos , Neisseria gonorrhoeae/clasificación , Neisseria gonorrhoeae/efectos de los fármacos , Polimorfismo de Nucleótido Simple , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Femenino , Genes Bacterianos , Gonorrea/microbiología , Humanos , Masculino , Mutación Missense , Neisseria gonorrhoeae/aislamiento & purificación
18.
Biofouling ; 29(8): 917-28, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23879183

RESUMEN

A model biofilm, formed of multiple species from environmental drinking water, including opportunistic pathogens, was created to explore the tolerance of multi-species biofilms to chlorine levels typical of water-distribution systems. All species, when grown planktonically, were killed by concentrations of chlorine within the World Health Organization guidelines (0.2-5.0 mg l(-1)). Higher concentrations (1.6-40-fold) of chlorine were required to eradicate biofilm populations of these strains, ~70% of biofilms tested were not eradicated by 5.0 mg l(-1) chlorine. Pathogenic bacteria within the model multi-species biofilms had an even more substantial increase in chlorine tolerance; on average ~700-1100 mg l(-1) chlorine was required to eliminate pathogens from the biofilm, 50-300-fold higher than for biofilms comprising single species. Confocal laser scanning microscopy of biofilms showed distinct 3D structures and multiple cell morphologies and arrangements. Overall, this study showed a substantial increase in the chlorine tolerance of individual species with co-colonization in a multi-species biofilm that was far beyond that expected as a result of biofilm growth on its own.


Asunto(s)
Fenómenos Fisiológicos Bacterianos/efectos de los fármacos , Biopelículas/efectos de los fármacos , Cloro/farmacología , Desinfectantes/farmacología , Agua Potable/microbiología , Purificación del Agua , Bacterias/crecimiento & desarrollo , Biopelículas/crecimiento & desarrollo , Desinfección , Microscopía Confocal
19.
Dig Dis Sci ; 54(6): 1337-46, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19242792

RESUMEN

BACKGROUND AND AIMS: Hepatitis B viral markers and liver tests were used as predictors for development of hepatocellular carcinoma and progression to end-stage liver disease in 128 cirrhosis patients with hepatitis B. RESULTS: During a median follow-up of 63.5 months, 28 patients (21.9%) developed HCC and 36 (28.1%) died from non-HCC liver deaths. By multivariate analysis, independent predictors of HCC development and their hazard ratios were high alfa-fetoprotein (HR2.83, 95% CI 1.60-5.00, P = 0.0003), negative HBeAg (HR2.33, 95% CI 1.04-5.29, P = 0.04), and low alanine aminotransferase value (HR1.42, 95% CI 1.08-1.89, P = 0.02). Independent predictors of non-HCC liver deaths were HBeAg positivity (HR3.39, 95% CI 1.16-9.93, P = 0.02), decrease albumin (HR1.61, 95% CI 0.99-2.63, P = 0.05), decrease platelet count (HR2.54, 95% CI 1.03-6.25, P = 0.04), high ALT value (HR1.22, 95% CI 1.03-1.43, P = 0.02), and onset of encephalopathy (HR3.34, 95% CI 1.21-9.27, P = 0.02). CONCLUSIONS: HBeAg negativity, elevated AFP, and low ALT values predicted HCC development, while HBeAg positivity, abnormal liver tests, and low platelet counts identified patients with non-HCC liver deaths.


Asunto(s)
Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B/patología , Cirrosis Hepática/patología , Cirrosis Hepática/virología , Adolescente , Adulto , Anciano , Antivirales/uso terapéutico , Biomarcadores , Femenino , Hepatitis B/tratamiento farmacológico , Hepatitis B/mortalidad , Humanos , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Factores de Riesgo , Adulto Joven
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