RESUMEN
Callistemon viminalis has been widely known due to its therapeutic properties. Tuberculosis is a deadly infectious disease caused predominantly by Mycobacterium tuberculosis. Other respiratory diseases may also be caused by nontuberculous mycobacteria. Malassezia furfur causes dermal inflammation and tissue damage. This study aimed to evaluate in vitro inhibitory effects of essential oils (EOs) from C. viminalis leaves (EO-CL) and flowers (EO-CF) against M. tuberculosis, Mycobacterium kansasii, Mycobacterium avium and M. furfur strains. Their cytotoxic activity was evaluated by the brine shrimp assay. Resulting MIC values of all EOs under study were promising since they ranged from 50 to 100 µg/mL. Both EO-CL and EO-CF showed nontoxicity against Artemia salina by the brine shrimp assay (LC50 > 1000 µg/mL). GC-FID and GC-MS analyses showed that 1,8-cineole was the major component of both EOs. These results revealed the promising potential of EO-CL and EO-CF to develop new antibacterial and antifungal drugs.
RESUMEN
BACKGROUND: Spinal cord injury (SCI) disrupts intestinal barrier function, thereby increasing antigen permeation and leading to poor outcomes. Despite the intestinal tract's anatomic and physiologic heterogeneity, studies following SCI have not comprehensively addressed intestinal pathophysiology with regional specificity. AIMS AND METHODS: We used an experimental model of high thoracic SCI to investigate (1) regional mucosal oxidative stress using dihydroethidium labeling; (2) regional paracellular permeability to small- and large-molecular probes via Ussing chamber; (3) regional intestinal tight junction (TJ) protein expression; and (4) hindgut perfusion via the caudal mesenteric artery. RESULTS: Dihydroethidium staining was significantly elevated within duodenal mucosa at 3-day post-SCI. Molar flux of [14C]-urea was significantly elevated in duodenum and proximal colon at 3-day post-SCI, while molar flux of [3H]-inulin was significantly elevated only in duodenum at 3-day post-SCI. Barrier permeability was mirrored by a significant increase in the expression of pore-forming TJ protein claudin-2 in duodenum and proximal colon at 3-day post-SCI. Claudin-2 expression remained significantly elevated in proximal colon at 3-week post-SCI. Expression of the barrier-forming TJ protein occludin was significantly reduced in duodenum at 3-day post-SCI. Caudal mesenteric artery flow was unchanged by SCI at 3 days or 3 weeks despite significant reductions in mean arterial pressure. CONCLUSION: These data show that T3-SCI provokes elevated mucosal oxidative stress, altered expression of TJ proteins, and elevated intestinal barrier permeability in the proximal intestine. In contrast, mucosal oxidative stress and intestinal barrier permeability were unchanged in the hindgut after SCI. This regional heterogeneity may result from differential sensitivity to reduced mesenteric perfusion, though further studies are required to establish a causal link. Understanding regional differences in intestinal pathophysiology is essential for developing effective treatments and standards of care for individuals with SCI.
RESUMEN
This study reports on the chemical composition and antileishmanial and anticandidal activities of volatile oils (VOs) of Schinus molle dried leaves (SM), Cinnamomum cassia branch bark (CC) and their blends. Major constituents of SM were spathulenol (26.93 %), ß-caryophyllene (19.90 %), and caryophyllene oxide (12.69 %), whereas (E)-cinnamaldehyde (60.11 %), cinnamyl acetate (20.90 %) and cis-2-methoxycinnamic acid (10.37 %) were predominant in CC. SM (IC50=21.45â µg/mL) and CC (IC50=23.27â µg/mL) displayed good activity against L.â amazonensis promastigotes, besides having good or moderate activity against nine Candida strains, with Minimum Inhibitory Concentration (MIC) values ranging from 31.25 to 250â µg/mL. While the three SM and CC blends were not more active than the VOs tested individually, they exhibited remarkably high antileishmanial activity, with IC50 values ranging between 3.12 and 7.04â µg/mL, which is very similar to the IC50 of amphotericin B (positive control).
RESUMEN
Here, we demonstrate a structure-based small molecule virtual screening and lead optimization pipeline using a homology model of a difficult-to-drug G-protein-coupled receptor (GPCR) target. Protease-activated receptor 4 (PAR4) is activated by thrombin cleavage, revealing a tethered ligand that activates the receptor, making PAR4 a challenging target. A virtual screen of a make-on-demand chemical library yielded a one-hit compound. From the single-hit compound, we developed a novel series of PAR4 antagonists. Subsequent lead optimization via simultaneous virtual library searches and structure-based rational design efforts led to potent antagonists of thrombin-induced activation. Interestingly, this series of antagonists was active against PAR4 activation by the native protease thrombin cleavage but not the synthetic PAR4 agonist peptide AYPGKF.
RESUMEN
Histopathology plays a critical role in the diagnosis and surgical management of cancer. However, access to histopathology services, especially frozen section pathology during surgery, is limited in resource-constrained settings because preparing slides from resected tissue is time-consuming, labor-intensive, and requires expensive infrastructure. Here, we report a deep-learning-enabled microscope, named DeepDOF-SE, to rapidly scan intact tissue at cellular resolution without the need for physical sectioning. Three key features jointly make DeepDOF-SE practical. First, tissue specimens are stained directly with inexpensive vital fluorescent dyes and optically sectioned with ultra-violet excitation that localizes fluorescent emission to a thin surface layer. Second, a deep-learning algorithm extends the depth-of-field, allowing rapid acquisition of in-focus images from large areas of tissue even when the tissue surface is highly irregular. Finally, a semi-supervised generative adversarial network virtually stains DeepDOF-SE fluorescence images with hematoxylin-and-eosin appearance, facilitating image interpretation by pathologists without significant additional training. We developed the DeepDOF-SE platform using a data-driven approach and validated its performance by imaging surgical resections of suspected oral tumors. Our results show that DeepDOF-SE provides histological information of diagnostic importance, offering a rapid and affordable slide-free histology platform for intraoperative tumor margin assessment and in low-resource settings.
Asunto(s)
Aprendizaje Profundo , Microscopía , Colorantes Fluorescentes , Hematoxilina , Eosina Amarillenta-(YS)RESUMEN
We developed a set of two precision, small-scale, water balance lysimeters to provide accurate measurements of bare soil evaporation. Each lysimeter comprises a soil tank, a balance assembly with load cell, a wicking drainage system, and a stilling well to measure drained water. Fiberglass wicks installed at the bottom of the soil tanks provide -60 cm of tension to the base of the soil column, and soil water drainage is quantified to close the water balance within the lysimeter. The calibrated lysimeters return mass changes with uncertainties ranging from 3 to 8 g, corresponding to uncertainties of 0.02-0.05 mm of water. Installed at a semi-arid site in northern Nevada, the two lysimeters are filled with uniform construction sand and silt loam. Over a six-month pilot observation period, bare soil evaporation rates of 0.19 and 0.40 mm/day were measured for the construction sand and silt loam, respectively, which is consistent with meteorological data and models of potential evapotranspiration at the site. The design of the lysimeter can be adapted to specific research goals or site restrictions, and these instruments can contribute significantly to our ability to close the soil water balance.
RESUMEN
OBJECTIVE: Early detection and treatment of cervical precancers can prevent disease progression. However, in low-resource communities with a high incidence of cervical cancer, high equipment costs and a shortage of specialists hinder preventative strategies. This manuscript presents a low-cost multiscale in vivo optical imaging system coupled with a computer-aided diagnostic system that could enable accurate, real-time diagnosis of high-grade cervical precancers. METHODS: The system combines portable colposcopy and high-resolution endomicroscopy (HRME) to acquire spatially registered widefield and microscopy videos. A multiscale imaging fusion network (MSFN) was developed to identify cervical intraepithelial neoplasia grade 2 or more severe (CIN 2+). The MSFN automatically identifies and segments the ectocervix and lesions from colposcopy images, extracts nuclear morphology features from HRME videos, and integrates the colposcopy and HRME information. RESULTS: With a threshold value set to achieve sensitivity equal to clinical impression (0.98 [p = 1.0]), the MSFN achieved a significantly higher specificity than clinical impression (0.75 vs. 0.43, p = 0.000006). CONCLUSION: Our findings show that multiscale optical imaging of the cervix allows the highly sensitive and specific detection of high-grade precancers. SIGNIFICANCE: The multiscale imaging system and MSFN could facilitate the accurate, real-time diagnosis of cervical precancers in low-resource settings.
Asunto(s)
Colposcopía , Neoplasias del Cuello Uterino , Femenino , Humanos , Colposcopía/métodos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Imagen Óptica/métodos , Lesiones Precancerosas/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Displasia del Cuello del Útero/diagnóstico por imagen , Displasia del Cuello del Útero/patología , Microscopía/métodos , Cuello del Útero/diagnóstico por imagen , Cuello del Útero/patología , Adulto , Sensibilidad y EspecificidadRESUMEN
Antibodies targeting an envelope dimer epitope (EDE) cross-neutralize Zika virus (ZIKV) and dengue virus (DENV) and have thus inspired an epitope-focused vaccine design. There are two EDE antibody subclasses (EDE1, EDE2) distinguished by their dependence on viral envelope protein N-linked glycosylation at position N153 (DENV) or N154 (ZIKV) for binding. Here, we determined how envelope glycosylation site mutations affect neutralization by EDE and other broadly neutralizing antibodies. Consistent with structural studies, mutations abolishing the N153/N154 glycosylation site increased DENV and ZIKV sensitivity to neutralization by EDE1 antibodies. Surprisingly, despite their location at predicted contact sites, these mutations also increased sensitivity to EDE2 antibodies. Moreover, despite preserving the glycosylation site motif (N-X-S/T), substituting the threonine at ZIKV envelope residue 156 with a serine resulted in loss of glycan occupancy accompanied with increased neutralization sensitivity to EDE antibodies. For DENV, the presence of a serine instead of a threonine at envelope residue 155 retained glycan occupancy, but nonetheless increased sensitivity to EDE antibodies, in some cases to a similar extent as mutation at N153, which abolishes glycosylation. Envelope glycosylation site mutations also increased ZIKV and DENV sensitivity to other non-EDE broadly neutralizing antibodies, but had limited effects on ZIKV- or DENV-specific antibodies. Thus, envelope protein glycosylation is context-dependent and modulates the potency of broadly neutralizing antibodies in a manner not predicted by existing structures. Manipulating envelope protein glycosylation could be a novel strategy for engineering vaccine antigens to elicit antibodies that broadly neutralize ZIKV and DENV.IMPORTANCEAntibodies that potently cross-neutralize Zika (ZIKV) and dengue (DENV) viruses are attractive to induce via vaccination to protect against these co-circulating flaviviruses. Structural studies have shown that viral envelope protein glycosylation is important for binding by one class of these so-called broadly neutralizing antibodies, but less is known about its effect on neutralization. Here, we investigated how envelope protein glycosylation site mutations impact the potency of broadly neutralizing antibodies against ZIKV and DENV. We found that glycan occupancy was not always predicted by an intact N-X-S/T sequence motif. Moreover, envelope protein glycosylation site mutations alter the potency of broadly neutralizing antibodies in a manner unexpected from their predicted binding mechanism as determined by existing structures. We therefore highlight the complex role and determinants of envelope protein glycosylation that should be considered in the design of vaccine antigens to elicit broadly neutralizing antibodies.
Asunto(s)
Virus del Dengue , Dengue , Flavivirus , Vacunas , Infección por el Virus Zika , Virus Zika , Humanos , Anticuerpos ampliamente neutralizantes , Glicosilación , Anticuerpos Neutralizantes , Virus del Dengue/genética , Proteínas del Envoltorio Viral/química , Anticuerpos Antivirales , Epítopos/genética , Mutación , Polisacáridos , Serina/genética , Treonina/genéticaRESUMEN
Diet is a primary source of nutrients but also toxic metal exposure. In pregnancy, balancing essential metal exposure while reducing non-essential ones is vital for fetal and maternal health. However, the effect of metal mixtures from diets like the Mediterranean, known for health benefits, remains unclear. This study aimed to explore the association between Mediterranean diet adherence and metals exposure, both individually and as mixtures. The study involved 907 pregnant participants from the New Hampshire Birth Cohort Study. We calculated the relative Mediterranean diet score (rMED) through a validated food frequency questionnaire, which includes 8 traditional Mediterranean dietary components. Also, at ~24-28 weeks of gestation, we used ICP-MS to measure speciation of Al, Cd, Co, Cu, Fe, Hg, Mo, Ni, Sb, Se, Sn, Zn, and As in urine, as well as Pb, Hg, As, Ni, and Se in toenails. We used multiple linear regression and Weighted Quantile Sum regression to analyze the association between rMED and metal mixtures. The models were adjusted for age, pre-pregnancy BMI, smoking during pregnancy, and educational level. High adherence to the Mediterranean diet was associated with increased urinary Al (® = 0.26 (95 % confidence interval (CI) = 0.05; 0.46)), Cd (ß = 0.12 (95%CI = 0.00; 0.24)), Mo (ß = 0.10 (95%CI = 0.00; 0.20)), and AsB (ß = 0.88 (95%CI = 0.49; 1.27)) as well as toenail Hg (ß = 0.44 (95%CI = 0.22; 0.65)), Ni (ß = 0.37 (95%CI = 0.06; 0.67)), and Pb (ß = 0.22 (95%CI = 0.03; 0.40)) compared to those with low adherence. The intake of fruits and nuts, fish and seafood, legumes, cereals, meat, and olive oil were found to be related to the metal biomarkers within the rMED. In conclusion, the Mediterranean diet enhances essential metal intake but may also increase exposure to harmful ones.
Asunto(s)
Dieta Mediterránea , Mercurio , Embarazo , Femenino , Animales , Humanos , Estudios de Cohortes , Cadmio , New Hampshire , PlomoRESUMEN
IMPORTANCE: The wide endemic range of mosquito-vectored flaviviruses-such as Zika virus and dengue virus serotypes 1-4-places hundreds of millions of people at risk of infection every year. Despite this, there are no widely available vaccines, and treatment of severe cases is limited to supportive care. An avenue toward development of more widely applicable vaccines and targeted therapies is the characterization of monoclonal antibodies that broadly neutralize all these viruses. Here, we measure how single amino acid mutations in viral envelope protein affect neutralizing antibodies with both broad and narrow specificities. We find that broadly neutralizing antibodies with potential as vaccine prototypes or biological therapeutics are quantifiably more difficult to escape than narrow, virus-specific neutralizing antibodies.
Asunto(s)
Anticuerpos Antivirales , Anticuerpos ampliamente neutralizantes , Proteínas del Envoltorio Viral , Infección por el Virus Zika , Virus Zika , Animales , Humanos , Reacciones Cruzadas , Mutación , Vacunas , Envoltura Viral , Proteínas del Envoltorio Viral/genética , Virus Zika/genética , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/terapiaRESUMEN
Autobiographical memory for deceitful events is said to be forgotten over time to reduce guilt and stress. People who engage in deceitful behavior continue to do so because they are able to stretch their memories to match their moral outlook. In this study, the authors wanted to see if participants who engage in deceitful behavior will change their behavior if they are reminded of their previous misdeeds and compare it with reminding them of past moral behavior and any neutral event. We also studied how the experience, or phenomenology of remembering, differs between immoral and moral memories. In Experiment 1, we found evidence to suggest that reminding deceptive autobiographical memory does not reduce deceptive behavior. In Experiment 2, we found evidence to suggest phenomenological characteristics of Immoral and moral memories are not significantly different from each other but they are both significantly different from that of neutral memory. This contradicts established results in the field. It is interesting to note that only emotional valence is significantly different between immoral and moral memory.
RESUMEN
Zika virus and dengue virus are co-circulating flaviviruses with a widespread endemic range. Eliciting broad and potent neutralizing antibodies is an attractive goal for developing a vaccine to simultaneously protect against these viruses. However, the capacity of viral mutations to confer escape from broadly neutralizing antibodies remains undescribed, due in part to limited throughput and scope of traditional approaches. Here, we use deep mutational scanning to map how all possible single amino acid mutations in Zika virus envelope protein affect neutralization by antibodies of varying breadth and potency. While all antibodies selected viral escape mutations, the mutations selected by broadly neutralizing antibodies conferred less escape relative to those selected by narrow, virus-specific antibodies. Surprisingly, even for broadly neutralizing antibodies with similar binding footprints, different single mutations led to escape, indicating distinct functional requirements for neutralization not captured by existing structures. Additionally, the antigenic effects of mutations selected by broadly neutralizing antibodies were conserved across divergent, albeit related, flaviviruses. Our approach identifies residues critical for antibody neutralization, thus comprehensively defining the as-yet-unknown functional epitopes of antibodies with clinical potential.
RESUMEN
BACKGROUND: Fine needle aspiration cytology (FNAC) is a widely used diagnostic tool to evaluate salivary gland tumours. The Milan system for reporting salivary gland cytopathology allows for standardisation and facilitates cytologicalhistological correlation. However, FNAC findings can still pose a diagnostic challenge. The accuracy of FNAC should be assessed at each centre. The aim of this study was to assess the concordance of FNAC and final histology of salivary gland tumours in three academic hospitals affiliated with the University of Pretoria, South Africa. METHODS: The study was a cross-sectional retrospective analytical study of 214 patients who underwent an operation for salivary gland tumours. All patients with FNAC and histology results between 2007-2017 were included. Patients were recruited from three University of Pretoria, South Africa, affiliated hospitals: Steve Biko Academic, Kalafong Provincial Tertiary and Tembisa Provincial Tertiary Hospital. RESULTS: Of the 214 patients with salivary gland tumours, the majority were located in the parotid gland (56.1%). Pleomorphic adenoma was the most common tumour (62.6%). The FNAC sensitivity, specificity and diagnostic accuracy (receiver operating characteristic) were 92.7%, 98.1% and 0.95 respectively. The concordance between salivary gland tumour FNAC and final histology was 96.95% with a Cohen's kappa coefficient of 0.91 (p= 0.0001). CONCLUSION: There is strong concordance between FNAC and histology of salivary gland tumours. FNAC is an accurate, minimally invasive diagnostic tool with high sensitivity and specificity. It provides the clinician with a reliable preoperative diagnosis determining whether the salivary gland tumour is benign or malignant.
Asunto(s)
Neoplasias de las Glándulas Salivales , Humanos , Estudios Retrospectivos , Biopsia con Aguja Fina/métodos , Estudios Transversales , Neoplasias de las Glándulas Salivales/diagnóstico , Neoplasias de las Glándulas Salivales/patología , Neoplasias de las Glándulas Salivales/cirugía , Glándulas Salivales/patologíaRESUMEN
Characterization of microvascular changes during neoplastic progression has the potential to assist in discriminating precancer and early cancer from benign lesions. Here, we introduce a novel high-resolution microendoscope that leverages scanning darkfield reflectance imaging to characterize angiogenesis without exogenous contrast agents. Scanning darkfield imaging is achieved by coupling programmable illumination with a complementary metal-oxide semiconductor (CMOS) camera rolling shutter, eliminating the need for complex optomechanical components and making the system portable, low-cost (<$5,500) and simple to use. Imaging depth is extended by placing a gradient-index (GRIN) lens at the distal end of the imaging fiber to resolve subepithelial microvasculature. We validated the capability of the scanning darkfield microendoscope to visualize microvasculature at different anatomic sites in vivo by imaging the oral cavity of healthy volunteers. Images of cervical specimens resected for suspected neoplasia reveal distinct microvascular patterns in columnar and squamous epithelium with different grades of precancer, indicating the potential of scanning darkfield microendoscopy to aid in efforts to prevent cervical cancer through early diagnosis.
RESUMEN
With the recent advance in molecular phylogenetics focused on the leaf insects (Phasmatodea, Phylliidae), gaps in knowledge are beginning to be filled. Yet, shortcomings are also being highlighted, for instance, the unveiling of numerous undescribed phylliid species. Here, some of these taxa are described, including Phylliumiyadaonsp. nov. from Mindoro Island, Philippines; Phylliumsamarensesp. nov. from Samar Island, Philippines; Phylliumortizisp. nov. from Mindanao Island, Philippines; Pulchriphylliumheraclessp. nov. from Vietnam; Pulchriphylliumdelisleisp. nov. from South Kalimantan, Indonesia; and Pulchriphylliumbhaskaraisp. nov. from Java, Indonesia. Several additional specimens of these species together with a seventh species described herein, Pulchriphylliumanangusp. nov. from southwestern India, were incorporated into a newly constructed phylogenetic tree. Additionally, two taxa that were originally described as species, but in recent decades have been treated as subspecies, are elevated back to species status to reflect their unique morphology and geographic isolation, creating the following new combinations: Pulchriphylliumscythe (Gray, 1843) stat. rev., comb. nov. from Bangladesh and northeastern India, and Pulchriphylliumcrurifolium (Audinet-Serville, 1838) stat. rev., comb. nov. from the Seychelles islands. Lectotype specimens are also designated for Pulchriphylliumscythe (Gray, 1843) stat. rev., comb. nov. and Pulchriphylliumcrurifolium (Audinet-Serville, 1838) stat. rev., comb. nov. from original type material.
RESUMEN
Scaffold attachment factor B (SAFB) is a conserved RNA-binding protein that is essential for early mammalian development. However, the functions of SAFB in mouse embryonic stem cells (ESCs) have not been characterized. Using RNA immunoprecipitation followed by RNA-seq (RIP-seq), we examined the RNAs associated with SAFB in wild-type and SAFB/SAFB2 double-knockout ESCs. SAFB predominantly associated with introns of protein-coding genes through purine-rich motifs. The transcript most enriched in SAFB association was the lncRNA Malat1, which also contains a purine-rich region in its 5' end. Knockout of SAFB/SAFB2 led to differential expression of approximately 1000 genes associated with multiple biological processes, including apoptosis, cell division, and cell migration. Knockout of SAFB/SAFB2 also led to splicing changes in a set of genes that were largely distinct from those that exhibited changes in expression level. The spliced and nascent transcripts of many genes whose expression levels were positively regulated by SAFB also associated with high levels of SAFB, implying that SAFB binding promotes their expression. Reintroduction of SAFB into double-knockout cells restored gene expression toward wild-type levels, an effect again observable at the level of spliced and nascent transcripts. Proteomics analysis revealed a significant enrichment of nuclear speckle-associated and RS domain-containing proteins among SAFB interactors. Neither Xist nor Polycomb functions were dramatically altered in SAFB/2 knockout ESCs. Our findings suggest that among other potential functions in ESCs, SAFB promotes the expression of certain genes through its ability to bind nascent RNA.
Asunto(s)
Células Madre Embrionarias de Ratones , ARN , Animales , Ratones , Expresión Génica , Intrones , Mamíferos , Ratones NoqueadosRESUMEN
During mouse embryogenesis, expression of the long non-coding RNA (lncRNA) Airn leads to gene repression and recruitment of Polycomb repressive complexes (PRCs) to varying extents over a 15-Mb domain. The mechanisms remain unclear. Using high-resolution approaches, we show in mouse trophoblast stem cells that Airn expression induces long-range changes to chromatin architecture that coincide with PRC-directed modifications and center around CpG island promoters that contact the Airn locus even in the absence of Airn expression. Intensity of contact between the Airn lncRNA and chromatin correlated with underlying intensity of PRC recruitment and PRC-directed modifications. Deletion of CpG islands that contact the Airn locus altered long-distance repression and PRC activity in a manner that correlated with changes in chromatin architecture. Our data imply that the extent to which Airn expression recruits PRCs to chromatin is controlled by DNA regulatory elements that modulate proximity of the Airn lncRNA product to its target DNA.
Asunto(s)
ARN Largo no Codificante , Animales , Ratones , Cromatina , Desarrollo Embrionario , Proteínas del Grupo Polycomb/genética , Proteínas del Grupo Polycomb/metabolismo , Regiones Promotoras Genéticas/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismoRESUMEN
Cardiac complications from mediastinal radiotherapy are much more prevalent than in years past and are becoming a significant cause of morbidity and mortality in these patients following treatment. We describe a patient with metastatic lung adenosquamous carcinoma extending to the right ventricular outflow tract who would develop a Mobitz type II atrioventricular block following intracardiac radiation therapy requiring permanent pacemaker placement.
RESUMEN
High-risk human papillomavirus (HPV) DNA testing is widely acknowledged as the most sensitive cervical cancer screening method but has limited availability in resource-limited settings, where the burden of cervical cancer is highest. Recently, HPV DNA tests have been developed for use in resource-limited settings, but they remain too costly for widespread use and require instruments that are often limited to centralized laboratories. To help meet the global need for low-cost cervical cancer screening, we developed a prototype, sample-to-answer, point-of-care test for HPV16 and HPV18 DNA. Our test relies on isothermal DNA amplification and lateral flow detection, two technologies that reduce the need for complex instrumentation. We integrated all test components into a low-cost, manufacturable platform, and performance of the integrated test was evaluated with synthetic samples, provider-collected clinical samples in a high-resource setting in the United States, and self-collected clinical samples in a low-resource setting in Mozambique. We demonstrated a clinically relevant limit of detection of 1000 HPV16 or HPV18 DNA copies per test. The test requires six user steps, yields results in 45 min, and can be performed using a benchtop instrument and minicentrifuge by minimally trained personnel. The projected per-test cost is <$5, and the projected instrumentation cost is <$1000. These results show the feasibility of a sample-to-answer, point-of-care HPV DNA test. With the inclusion of other HPV types, this test has the potential to fill a critical gap for decentralized and globally accessible cervical cancer screening.
Asunto(s)
Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/genética , Infecciones por Papillomavirus/diagnóstico , Configuración de Recursos Limitados , Detección Precoz del Cáncer/métodos , ADN Viral/genética , Técnicas de Amplificación de Ácido Nucleico/métodosRESUMEN
We report that when expressed at similar levels from an isogenic locus, the Airn lncRNA induces Polycomb deposition with a potency that rivals Xist . However, when subject to the same degree of promoter activation, Xist is more abundant and more potent than Airn . Our data definitively demonstrate that the Airn lncRNA is functional and suggest that Xist achieved extreme potency in part by evolving mechanisms to promote its own abundance.