110 research outputs found
CUT-PCR: CRISPR-mediated, ultrasensitive detection of target DNA using PCR
Circulating tumor DNA (ctDNA) has emerged as a tumor-specific biomarker for the early detection of various cancers. To date, several techniques have been devised to enrich the extremely small amounts of ctDNA present in plasma, but they are still insufficient for cancer diagnosis, especially at the early stage. Here, we developed a novel method, CUT (CRISPR-mediated, Ultrasensitive detection of Target DNA)-PCR, which uses CRISPR endonucleases to enrich and detect the extremely small amounts of tumor DNA fragments among the much more abundant wild-type DNA fragments by specifically eliminating the wild-type sequences. We computed that by using various orthologonal CRISPR endonucleases such as SpCas9 and FnCpf1, the CUT-PCR method would be applicable to 80% of known cancer-linked substitution mutations registered in the COSMIC database. We further verified that CUT-PCR together with targeted deep sequencing enables detection of a broad range of oncogenes with high sensitivity (<0.01%) and accuracy, which is superior to conventional targeted deep sequencing. In the end, we successfully applied CUT-PCR to detect sequences with oncogenic mutations in the ctDNA of colorectal cancer patients' blood, suggesting that our technique could be adopted for diagnosing various types of cancer at early stages
Regulated Nuclear Trafficking of rpL10A Mediated by NIK1 Represents a Defense Strategy of Plant Cells against Virus
The NSP-interacting kinase (NIK) receptor-mediated defense pathway has been identified recently as a virulence target of the geminivirus nuclear shuttle protein (NSP). However, the NIK1–NSP interaction does not fit into the elicitor–receptor model of resistance, and hence the molecular mechanism that links this antiviral response to receptor activation remains obscure. Here, we identified a ribosomal protein, rpL10A, as a specific partner and substrate of NIK1 that functions as an immediate downstream effector of NIK1-mediated response. Phosphorylation of cytosolic rpL10A by NIK1 redirects the protein to the nucleus where it may act to modulate viral infection. While ectopic expression of normal NIK1 or a hyperactive NIK1 mutant promotes the accumulation of phosphorylated rpL10A within the nuclei, an inactive NIK1 mutant fails to redirect the protein to the nuclei of co-transfected cells. Likewise, a mutant rpL10A defective for NIK1 phosphorylation is not redirected to the nucleus. Furthermore, loss of rpL10A function enhances susceptibility to geminivirus infection, resembling the phenotype of nik1 null alleles. We also provide evidence that geminivirus infection directly interferes with NIK1-mediated nuclear relocalization of rpL10A as a counterdefensive measure. However, the NIK1-mediated defense signaling neither activates RNA silencing nor promotes a hypersensitive response but inhibits plant growth and development. Although the virulence function of the particular geminivirus NSP studied here overcomes this layer of defense in Arabidopsis, the NIK1-mediated signaling response may be involved in restricting the host range of other viruses
Mammography-based screening program: preliminary results from a first 2-year round in a Brazilian region using mobile and fixed units
RLH, TBS and ALF made substantial contributions to the conception and
design of the article, the acquisition, analysis and interpretation of the data,
and drafting of the article. ECM, JSCM and NB made substantial
contributions to the conception and design of the study.Background: Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer deaths
among women worldwide. The use of mobile mammography units to offer screening to women living in remote
areas is a rational strategy to increase the number of women examined. This study aimed to evaluate results from
the first 2 years of a government-organized mammography screening program implemented with a mobile unit
(MU) and a fixed unit (FU) in a rural county in Brazil. The program offered breast cancer screening to women living
in Barretos and the surrounding area.
Methods: Based on epidemiologic data, 54 238 women, aged 40 to 69 years, were eligible for breast cancer
screening. The study included women examined from April 1, 2003 to March 31, 2005. The chi-square test and
Bonferroni correction analyses were used to evaluate the frequencies of tumors and the importance of clinical
parameters and tumor characteristics. Significance was set at p < 0.05.
Results: Overall, 17 964 women underwent mammography. This represented 33.1% of eligible women in the area.
A mean of 18.6 and 26.3 women per day were examined in the FU and MU, respectively. Seventy six patients were
diagnosed with breast cancer (41 (54%) in the MU). This represented 4.2 cases of breast cancer per 1000
examinations. The number of cancers detected was significantly higher in women aged 60 to 69 years than in
those aged 50 to 59 years (p < 0.001) or 40 to 49 years (p < 0.001). No difference was observed between women
aged 40 to 49 years and those aged 50 to 59 years (p = 0.164). The proportion of tumors in the early (EC 0 and EC
I) and advanced (CS III and CS IV) stages of development were 43.4% and 15.8%, respectively.
Conclusions: Preliminary results indicate that this mammography screening program is feasible for implementation
in a rural Brazilian territory and favor program continuation
Ecological approaches in veterinary epidemiology: mapping the risk of bat-borne rabies using vegetation indices and night-time light satellite imagery
Rabies remains a disease of significant public health concern. In the Americas, bats are an important source of rabies for pets, livestock, and humans. For effective rabies control and prevention, identifying potential areas for disease occurrence is critical to guide future research, inform public health policies, and design interventions. To anticipate zoonotic infectious diseases distribution at coarse scale, veterinary epidemiology needs to advance via exploring current geographic ecology tools and data using a biological approach. We analyzed bat-borne rabies reports in Chile from 2002 to 2012 to establish associations between rabies occurrence and environmental factors to generate an ecological niche model (ENM). The main rabies reservoir in Chile is the bat species Tadarida brasiliensis; we mapped 726 occurrences of rabies virus variant AgV4 in this bat species and integrated them with contemporary Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS). The correct prediction of areas with rabies in bats and the reliable anticipation of human rabies in our study illustrate the usefulness of ENM for mapping rabies and other zoonotic pathogens. Additionally, we highlight critical issues with selection of environmental variables, methods for model validation, and consideration of sampling bias. Indeed, models with weak or incorrect validation approaches should be interpreted with caution. In conclusion, ecological niche modeling applications for mapping disease risk at coarse geographic scales have a promising future, especially with refinement and enrichment of models with additional information, such as night-time light data, which increased substantially the model’s ability to anticipate human rabies
Panel 7: otitis media:treatment and complications
Objective: We aimed to summarize key articles published between 2011 and 2015 on the treatment of (recurrent) acute otitis media, otitis media with effusion, tympanostomy tube otorrhea, chronic suppurative otitis media and complications of otitis media, and their implications for clinical practice. Data Sources: PubMed, Ovid Medline, the Cochrane Library, and Clinical Evidence (BMJ Publishing). Review Methods: All types of articles related to otitis media treatment and complications between June 2011 and March 2015 were identified. A total of 1122 potential related articles were reviewed by the panel members; 118 relevant articles were ultimately included in this summary. Conclusions: Recent literature and guidelines emphasize accurate diagnosis of acute otitis media and optimal management of ear pain. Watchful waiting is optional in mild to moderate acute otitis media; antibiotics do shorten symptoms and duration of middle ear effusion. The additive benefit of adenoidectomy to tympanostomy tubes in recurrent acute otitis media and otitis media with effusion is controversial and age dependent. Topical antibiotic is the treatment of choice in acute tube otorrhea. Symptomatic hearing loss due to persistent otitis media with effusion is best treated with tympanostomy tubes. Novel molecular and biomaterial treatments as adjuvants to surgical closure of eardrum perforations seem promising. There is insufficient evidence to support the use of complementary and alternative treatments. Implications for Practice: Emphasis on accurate diagnosis of otitis media, in its various forms, is important to reduce overdiagnosis, overtreatment, and antibiotic resistance. Children at risk for otitis media and its complications deserve special attention
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