Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
Add more filters










Publication year range
1.
Cureus ; 16(4): e58866, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38800170

ABSTRACT

Monkeypox is a zoonotic viral disease. Monkeypox was first reported in humans about 54 years ago. Prior to the global outbreak, monkeypox was endemic to the rainforests of central and western African countries. In the last three years, increasing numbers of human monkeypox have been reported from various countries. Responding to the severity, monkeypox was declared a Public Health Emergency of International Concern by the World Health Organization. In the absence of approved drugs or clinical studies, repurposed drugs and therapeutic medical countermeasures effective against other orthopoxviruses have been utilized to treat severe human monkeypox cases. Currently, clinical trials are underway exploring the potential therapeutic effectiveness of tecovirimate in human monkeypox cases. Monoclonal antibodies, IFN-ß, resveratrol, and 15 triple-targeting FDA-approved drugs represent potential new drug targets for human monkeypox, necessitating further research.

2.
Indian J Thorac Cardiovasc Surg ; 39(2): 211-215, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36785600

ABSTRACT

In our series of surgical pulmonary endarterectomies done for chronic thromboembolic pulmonary hypertension, we have incorporated the principle of hydrodissection with the aid of a carbon dioxide (CO2) mist blower which is routinely used for off-pump coronary artery bypass (OPCAB) surgeries. This added method of endarterectomy will help to achieve optimum clearance of thrombic load with basic cardiac surgical instruments. Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-023-01476-w.

3.
Emerg Microbes Infect ; 5(8): e90, 2016 Aug 17.
Article in English | MEDLINE | ID: mdl-27530749

ABSTRACT

Outbreaks of zoonotic diseases in humans and livestock are not uncommon, and an important component in containment of such emerging viral diseases is rapid and reliable diagnostics. Such methods are often PCR-based and hence require the availability of sequence data from the pathogen. Rattus norvegicus (R. norvegicus) is a known reservoir for important zoonotic pathogens. Transmission may be direct via contact with the animal, for example, through exposure to its faecal matter, or indirectly mediated by arthropod vectors. Here we investigated the viral content in rat faecal matter (n=29) collected from two continents by analyzing 2.2 billion next-generation sequencing reads derived from both DNA and RNA. Among other virus families, we found sequences from members of the Picornaviridae to be abundant in the microbiome of all the samples. Here we describe the diversity of the picornavirus-like contigs including near-full-length genomes closely related to the Boone cardiovirus and Theiler's encephalomyelitis virus. From this study, we conclude that picornaviruses within R. norvegicus are more diverse than previously recognized. The virome of R. norvegicus should be investigated further to assess the full potential for zoonotic virus transmission.


Subject(s)
Disease Reservoirs , Feces/virology , Gastrointestinal Microbiome , Genetic Variation , Genome, Viral , Picornaviridae Infections/epidemiology , Picornaviridae/genetics , Rats/virology , Amino Acid Sequence , Animals , Denmark/epidemiology , High-Throughput Nucleotide Sequencing , Hong Kong/epidemiology , Humans , Malaysia/epidemiology , Metagenomics , Phylogeny , Picornaviridae/classification , Picornaviridae/isolation & purification , Picornaviridae Infections/transmission , RNA, Viral , Viral Proteins/chemistry , Viral Proteins/genetics , Zoonoses
4.
Oncotarget ; 7(35): 57239-57253, 2016 Aug 30.
Article in English | MEDLINE | ID: mdl-27528030

ABSTRACT

Tamoxifen is an effective anti-estrogen treatment for patients with estrogen receptor-positive (ER+) breast cancer, however, tamoxifen resistance is frequently observed. To elucidate the underlying molecular mechanisms of tamoxifen resistance, we performed a systematic analysis of miRNA-mediated gene regulation in three clinically-relevant tamoxifen-resistant breast cancer cell lines (TamRs) compared to their parental tamoxifen-sensitive cell line. Alterations in the expression of 131 miRNAs in tamoxifen-resistant vs. parental cell lines were identified, 22 of which were common to all TamRs using both sequencing and LNA-based quantitative PCR technologies. Although the target genes affected by the altered miRNA in the three TamRs differed, good agreement in terms of affected molecular pathways was observed. Moreover, we found evidence of miRNA-mediated regulation of ESR1, PGR1, FOXM1 and 14-3-3 family genes. Integrating the inferred miRNA-target relationships, we investigated the functional importance of 2 central genes, SNAI2 and FYN, which showed increased expression in TamR cells, while their corresponding regulatory miRNA were downregulated. Using specific chemical inhibitors and siRNA-mediated gene knockdown, we showed that both SNAI2 and FYN significantly affect the growth of TamR cell lines. Finally, we show that a combination of 2 miRNAs (miR-190b and miR-516a-5p) exhibiting altered expression in TamR cell lines were predictive of treatment outcome in a cohort of ER+ breast cancer patients receiving adjuvant tamoxifen mono-therapy. Our results provide new insight into the molecular mechanisms of tamoxifen resistance and may form the basis for future medical intervention for the large number of women with tamoxifen-resistant ER+ breast cancer.


Subject(s)
Breast Neoplasms/drug therapy , Drug Resistance, Neoplasm , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , MicroRNAs/metabolism , Tamoxifen/pharmacology , 14-3-3 Proteins/metabolism , Antineoplastic Agents, Hormonal/pharmacology , Breast/metabolism , Cell Line, Tumor , Cohort Studies , Estrogen Receptor alpha/metabolism , Female , Forkhead Box Protein M1/metabolism , Gene Expression Profiling , Humans , Intracellular Signaling Peptides and Proteins/metabolism , MCF-7 Cells , Nuclear Proteins/metabolism , RNA, Small Interfering/pharmacology , Snail Family Transcription Factors/metabolism
5.
Evol Med Public Health ; 2016(1): 219-26, 2016.
Article in English | MEDLINE | ID: mdl-27412864

ABSTRACT

BACKGROUND AND OBJECTIVES: Widespread use of antibiotics has resulted in selection pressure on genes that make bacteria non-responsive to antibiotics. These antibiotic-resistant bacteria are currently a major threat to global health. There are various possibilities for the transfer of antibiotic resistance genes. It has been argued that animal vectors such as Rattus norvegicus (R. norvegicus) living in hospital sewage systems are ideal for carrying pathogens responsible for fatal diseases in humans. METHODOLOGY: Using a metagenomic sequencing approach, we investigated faecal samples of R. norvegicus from three major cities for the presence of antibiotic resistance genes. RESULTS: We show that despite the shared resistome within samples from the same geographic locations, samples from hospital area carry significantly abundant vancomycin resistance genes. CONCLUSIONS AND IMPLICATIONS: The observed pattern is consistent with a selection for vancomycin genes in the R. norvegicus microbiome, potentially driven by the outflow of antibiotics and antibiotic-resistant bacteria into the wastewater systems. Carriage of vancomycin resistance may suggest that R. norvegicus is acting as a reservoir for possible transmission to the human population.

6.
Biomark Res ; 3: 9, 2015.
Article in English | MEDLINE | ID: mdl-26015868

ABSTRACT

BACKGROUND: Ovarian and triple-negative breast cancers with BRCA1 or BRCA2 loss are highly sensitive to treatment with PARP inhibitors and platinum-based cytotoxic agents and show an accumulation of genomic scars in the form of gross DNA copy number aberrations. Cancers without BRCA1 or BRCA2 loss but with accumulation of similar genomic scars also show increased sensitivity to platinum-based chemotherapy. Therefore, reliable biomarkers to identify DNA repair-deficient cancers prior to treatment may be useful for directing patients to platinum chemotherapy and possibly PARP inhibitors. Recently, three SNP array-based signatures of chromosomal instability were published that each quantitate a distinct type of genomic scar considered likely to be caused by improper DNA repair. They measure telomeric allelic imbalance (named NtAI), large scale transition (named LST), and loss of heterozygosity (named HRD-LOH), and it is suggested that these signatures may act as biomarkers for the state of DNA repair deficiency in a given cancer. RESULTS: We explored the pan-cancer distribution of scores of the three signatures utilizing a panel of 5371 tumors representing 15 cancer types from The Cancer Genome Atlas, and found a good correlation between scores of the three signatures (Spearman's ρ 0.73-0.87). In addition we found that cancer types ordinarily receiving platinum as standard of care have higher median scores of all three signatures. Interestingly, we also found that smaller subpopulations of high-scoring tumors exist in most cancer types, including those for which platinum chemotherapy is not standard therapy. CONCLUSIONS: Within several cancer types that are not ordinarily treated with platinum chemotherapy, we identified tumors with high levels of the three genomic biomarkers. These tumors represent identifiable subtypes of patients which may be strong candidates for clinical trials with PARP inhibitors or platinum-based chemotherapeutic regimens.

7.
Eur Urol ; 66(5): 936-48, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25047176

ABSTRACT

BACKGROUND: Candidate biomarkers have been identified for clear cell renal cell carcinoma (ccRCC) patients, but most have not been validated. OBJECTIVE: To validate published ccRCC prognostic biomarkers in an independent patient cohort and to assess intratumour heterogeneity (ITH) of the most promising markers to guide biomarker optimisation. DESIGN, SETTING, AND PARTICIPANTS: Cancer-specific survival (CSS) for each of 28 identified genetic or transcriptomic biomarkers was assessed in 350 ccRCC patients. ITH was interrogated in a multiregion biopsy data set of 10 ccRCCs. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Biomarker association with CSS was analysed by univariate and multivariate analyses. RESULTS AND LIMITATIONS: A total of 17 of 28 biomarkers (TP53 mutations; amplifications of chromosomes 8q, 12, 20q11.21q13.32, and 20 and deletions of 4p, 9p, 9p21.3p24.1, and 22q; low EDNRB and TSPAN7 expression and six gene expression signatures) were validated as predictors of poor CSS in univariate analysis. Tumour stage and the ccB expression signature were the only independent predictors in multivariate analysis. ITH of the ccB signature was identified in 8 of 10 tumours. Several genetic alterations that were significant in univariate analysis were enriched, and chromosomal instability indices were increased in samples expressing the ccB signature. The study may be underpowered to validate low-prevalence biomarkers. CONCLUSIONS: The ccB signature was the only independent prognostic biomarker. Enrichment of multiple poor prognosis genetic alterations in ccB samples indicated that several events may be required to establish this aggressive phenotype, catalysed in some tumours by chromosomal instability. Multiregion assessment may improve the precision of this biomarker. PATIENT SUMMARY: We evaluated the ability of published biomarkers to predict the survival of patients with clear cell kidney cancer in an independent patient cohort. Only one molecular test adds prognostic information to routine clinical assessments. This marker showed good and poor prognosis results within most individual cancers. Future biomarkers need to consider variation within tumours to improve accuracy.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/pathology , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Aged , Biopsy , Carcinoma, Renal Cell/mortality , DNA Mutational Analysis , Female , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic , Genetic Predisposition to Disease , Humans , Kaplan-Meier Estimate , Kidney Neoplasms/mortality , Male , Middle Aged , Multivariate Analysis , Mutation , Neoplasm Staging , Phenotype , Polymorphism, Single Nucleotide , Predictive Value of Tests , Proportional Hazards Models , Reproducibility of Results , Risk Factors , Time Factors , Transcriptome
8.
Methods Mol Biol ; 1097: 491-521, 2014.
Article in English | MEDLINE | ID: mdl-24639174

ABSTRACT

RNA binding proteins (RBPs) are key players in the regulation of gene expression. In this chapter we discuss the main protein-RNA recognition modes used by RBPs in order to regulate multiple steps of RNA processing. We discuss traditional and state-of-the-art technologies that can be used to study RNAs bound by individual RBPs, or vice versa, for both in vitro and in vivo methodologies. To help highlight the biological significance of RBP mediated regulation, online resources on experimentally verified protein-RNA interactions are briefly presented. Finally, we present the major tools to computationally infer RNA binding sites according to the modeling features and to the unsupervised or supervised frameworks that are adopted. Since some RNA binding site search algorithms are derived from DNA binding site search algorithms, we discuss the commonalities and novelties introduced to handle both sequence and structural features uniquely characterizing protein-RNA interactions.


Subject(s)
RNA-Binding Proteins/metabolism , RNA/metabolism , Binding Sites , Gene Expression Regulation , Models, Molecular , Molecular Conformation , Protein Binding , Protein Interaction Domains and Motifs , RNA/chemistry , RNA/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA-Binding Proteins/chemistry
9.
Cancer Discov ; 4(2): 175-185, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24436049

ABSTRACT

UNLABELLED: The contribution of whole-genome doubling to chromosomal instability (CIN) and tumor evolution is unclear. We use long-term culture of isogenic tetraploid cells from a stable diploid colon cancer progenitor to investigate how a genome-doubling event affects genome stability over time. Rare cells that survive genome doubling demonstrate increased tolerance to chromosome aberrations. Tetraploid cells do not exhibit increased frequencies of structural or numerical CIN per chromosome. However, the tolerant phenotype in tetraploid cells, coupled with a doubling of chromosome aberrations per cell, allows chromosome abnormalities to evolve specifically in tetraploids, recapitulating chromosomal changes in genomically complex colorectal tumors. Finally, a genome-doubling event is independently predictive of poor relapse-free survival in early-stage disease in two independent cohorts in multivariate analyses [discovery data: hazard ratio (HR), 4.70, 95% confidence interval (CI), 1.04-21.37; validation data: HR, 1.59, 95% CI, 1.05-2.42]. These data highlight an important role for the tolerance of genome doubling in driving cancer genome evolution. SIGNIFICANCE: Our work sheds light on the importance of whole-genome­doubling events in colorectal cancer evolution. We show that tetraploid cells undergo rapid genomic changes and recapitulate the genetic alterations seen in chromosomally unstable tumors. Furthermore, we demonstrate that a genome-doubling event is prognostic of poor relapse-free survival in this disease type.


Subject(s)
Chromosomal Instability , Neoplasms/genetics , Cell Line, Tumor , Colorectal Neoplasms/genetics , DNA Copy Number Variations , Humans , Neoplasms/mortality , Neoplasms/pathology , Phenotype , Ploidies , Polyploidy , Prognosis
10.
Invest Ophthalmol Vis Sci ; 54(8): 5169-75, 2013 Aug 05.
Article in English | MEDLINE | ID: mdl-23821202

ABSTRACT

PURPOSE: Ocular adnexal lymphoma (i.e., lymphoma with involvement of the orbit, eyelids, conjunctiva, lacrimal gland, and lacrimal sac), although rare, is common among malignant tumors involving the ocular adnexal region. The main subtypes are low-grade extranodal marginal zone lymphoma (EMZL) and aggressive diffuse large B-cell lymphoma (DLBCL). In rare cases, low-grade EMZL are reported to transform to DLBCL. It is unclear, however, which genetic events distinguish low-grade disease from aggressive, potentially fatal disease. METHODS: Using LNA-based arrays from Exiqon, we performed global microRNA (miRNA) expression profiling of 18 EMZLs and 25 DLBCLs involving ocular adnexal sites to investigate changes in the miRNA expression in low- versus high-grade disease. Findings were confirmed by real-time quantitative PCR (RTq-PCR). RESULTS: Our analysis revealed 43 miRNAs with altered expression profiles in DLBCL compared to EMZL. Seven of the miRNAs down-regulated in DLBCL relative to EMZL showed enrichment for a direct transcriptional repression by the oncoprotein MYC. We also report a possible loss-of-regulation of NFKB1 and its downstream miRNAs. In addition, our analysis identified a group of DLBCLs whose expression profiles resembled that of EMZL. Although transformation of EMZL to DLBCL in the ocular adnexal region is rare, we hypothesize that the intermediate group potentially may derive from transformation of EMZL that was not recognized by histology. CONCLUSIONS: We conclude that fundamental differences in miRNA expression exist between ocular adnexal EMZL and DLBCL, mainly due to differences in MYC and NF-ĸB regulatory pathways.


Subject(s)
Eye Neoplasms/genetics , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , NF-kappa B p50 Subunit/genetics , Proto-Oncogene Proteins c-myc/genetics , RNA, Neoplasm/genetics , Adult , Aged , Aged, 80 and over , Conjunctival Neoplasms/genetics , Conjunctival Neoplasms/metabolism , Conjunctival Neoplasms/pathology , Eye Neoplasms/metabolism , Eye Neoplasms/pathology , Female , Follow-Up Studies , Humans , Lacrimal Apparatus/metabolism , Lacrimal Apparatus/pathology , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoma, Large B-Cell, Diffuse/pathology , Male , MicroRNAs/biosynthesis , Middle Aged , NF-kappa B p50 Subunit/biosynthesis , Orbital Neoplasms/genetics , Orbital Neoplasms/metabolism , Orbital Neoplasms/pathology , Protein Array Analysis/methods , Proto-Oncogene Proteins c-myc/biosynthesis , RNA, Neoplasm/biosynthesis , Real-Time Polymerase Chain Reaction
11.
J Pathol ; 230(4): 356-64, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23716380

ABSTRACT

Intratumour heterogeneity (ITH) may foster tumour adaptation and compromise the efficacy of personalized medicine approaches. The scale of heterogeneity within a tumour (intratumour heterogeneity) relative to genetic differences between tumours (intertumour heterogeneity) is unknown. To address this, we obtained 48 biopsies from eight stage III and IV clear cell renal cell carcinomas (ccRCCs) and used DNA copy-number analyses to compare biopsies from the same tumour with 440 single tumour biopsies from the Cancer Genome Atlas (TCGA). Unsupervised hierarchical clustering of TCGA and multi-region ccRCC samples revealed segregation of samples from the same tumour into unrelated clusters; 25% of multi-region samples appeared more similar to unrelated samples than to any other sample originating from the same tumour. We found that the majority of recurrent DNA copy number driver aberrations in single biopsies were not present ubiquitously in late-stage ccRCCs and were likely to represent subclonal events acquired during tumour progression. Such heterogeneous subclonal genetic alterations within individual tumours may impair the identification of robust ccRCC molecular subtypes classified by distinct copy number alterations and clinical outcomes. The co-existence of distinct subclonal copy number events in different regions of individual tumours reflects the diversification of individual ccRCCs through multiple evolutionary routes and may contribute to tumour sampling bias and impact upon tumour progression and clinical outcome.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Renal Cell/genetics , DNA Copy Number Variations , Kidney Neoplasms/genetics , Biopsy , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/therapy , Chromosomal Instability , Clone Cells , Cluster Analysis , Computational Biology , DNA Mutational Analysis , Gene Expression Profiling/methods , Gene Regulatory Networks , Genetic Predisposition to Disease , Humans , Kidney Neoplasms/pathology , Kidney Neoplasms/therapy , Mutation , Neoplasm Staging , Oligonucleotide Array Sequence Analysis , Phenotype , Polymorphism, Single Nucleotide , Prognosis
12.
RNA ; 18(5): 900-14, 2012 May.
Article in English | MEDLINE | ID: mdl-22450757

ABSTRACT

Current genomic screens for noncoding RNAs (ncRNAs) predict a large number of genomic regions containing potential structural ncRNAs. The analysis of these data requires highly accurate prediction of ncRNA boundaries and discrimination of promising candidate ncRNAs from weak predictions. Existing methods struggle with these goals because they rely on sequence-based multiple sequence alignments, which regularly misalign RNA structure and therefore do not support identification of structural similarities. To overcome this limitation, we compute columnwise and global reliabilities of alignments based on sequence and structure similarity; we refer to these structure-based alignment reliabilities as STARs. The columnwise STARs of alignments, or STAR profiles, provide a versatile tool for the manual and automatic analysis of ncRNAs. In particular, we improve the boundary prediction of the widely used ncRNA gene finder RNAz by a factor of 3 from a median deviation of 47 to 13 nt. Post-processing RNAz predictions, LocARNA-P's STAR score allows much stronger discrimination between true- and false-positive predictions than RNAz's own evaluation. The improved accuracy, in this scenario increased from AUC 0.71 to AUC 0.87, significantly reduces the cost of successive analysis steps. The ready-to-use software tool LocARNA-P produces structure-based multiple RNA alignments with associated columnwise STARs and predicts ncRNA boundaries. We provide additional results, a web server for LocARNA/LocARNA-P, and the software package, including documentation and a pipeline for refining screens for structural ncRNA, at http://www.bioinf.uni-freiburg.de/Supplements/LocARNA-P/.


Subject(s)
Models, Molecular , RNA/chemistry , Software , Algorithms , Computational Biology/methods , Nucleic Acid Conformation , RNA, Untranslated/chemistry , Reproducibility of Results , Sequence Alignment
13.
Br J Haematol ; 157(4): 476-82, 2012 May.
Article in English | MEDLINE | ID: mdl-22404039

ABSTRACT

The chromosomal translocation t(12;21) resulting in the ETV6/RUNX1 fusion gene is the most frequent structural cytogenetic abnormality among patients with childhood acute lymphoblastic leukaemia (ALL). We investigated 62 ETV6/RUNX1-positive childhood ALL patients by single nucleotide polymorphism array to explore acquired copy number alterations (CNAs) at diagnosis. The mean number of CNAs was 2·82 (range 0-14). Concordance with available G-band karyotyping and comparative genomic hybridization was 93%. Based on three major protein-protein complexes disrupted by these CNAs, patients could be categorized into four distinct subgroups, defined by different underlying biological mechanisms relevant to the aetiology of childhood ALL. When recurrent CNAs were evaluated by an oncogenetic tree analysis classifying their sequential order, the most common genetic aberrations (deletions of 6q, 9p, 13q and X, and gains of 10 and 21) seemed independent of each other. Finally, we identified the most common regions with recurrent gains and losses, which comprise microRNA clusters with known oncogenic or tumour-suppressive roles. The present study sheds further light on the genetic diversity of ETV6/RUNX1-positive childhood ALL, which may be important for understanding poor responses among this otherwise highly curable subset of ALL and lead to novel targeted treatment strategies.


Subject(s)
Chromosome Aberrations , Oncogene Proteins, Fusion/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Adolescent , Child , Child, Preschool , Chromosome Banding , Comparative Genomic Hybridization , Computational Biology , Core Binding Factor Alpha 2 Subunit , Female , Genome-Wide Association Study , Humans , Infant , Male , Models, Genetic , Polymorphism, Single Nucleotide , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Treatment Outcome
14.
Mol Inform ; 30(2-3): 181-7, 2011 Mar 14.
Article in English | MEDLINE | ID: mdl-27466772

ABSTRACT

Ayurveda, the traditional Indian medicine is one of the most ancient, yet living medicinal traditions. In the present work, we developed an in silico library of natural products from Ayurveda medicine, coupled with structural information, plant origin and traditional therapeutic use. Following this, we compared their structures with those of drugs from DrugBank and we constructed a structural similarity network. Information on the traditional therapeutic use of the plants was integrated in the network in order to provide further evidence for the predicted biologically active natural compounds. We hereby present a number of examples where the traditional medicinal use of the plant matches with the medicinal use of the drug that is structurally similar to a plant component. With this approach, we have brought to light a number of obscure compounds of natural origin (e.g. kanugin, norruffscine, isoazadirolide) that could provide the basis and inspiration for further lead development. Apart from the identification of novel natural leads in drug discovery, we envisage that this integrated in silico ethnopharmacology approach could find applications in the elucidation of the molecular basis of Ayurveda medicine and in drug repurposing.

SELECTION OF CITATIONS
SEARCH DETAIL
...