Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Mol Syst Biol ; 19(8): e11686, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37325891

RESUMEN

The ongoing degradation of natural systems and other environmental changes has put our society at a crossroad with respect to our future relationship with our planet. While the concept of One Health describes how human health is inextricably linked with environmental health, many of these complex interdependencies are still not well-understood. Here, we describe how the advent of real-time genomic analyses can benefit One Health and how it can enable timely, in-depth ecosystem health assessments. We introduce nanopore sequencing as the only disruptive technology that currently allows for real-time genomic analyses and that is already being used worldwide to improve the accessibility and versatility of genomic sequencing. We showcase real-time genomic studies on zoonotic disease, food security, environmental microbiome, emerging pathogens, and their antimicrobial resistances, and on environmental health itself - from genomic resource creation for wildlife conservation to the monitoring of biodiversity, invasive species, and wildlife trafficking. We stress why equitable access to real-time genomics in the context of One Health will be paramount and discuss related practical, legal, and ethical limitations.


Asunto(s)
Ecosistema , Salud Única , Humanos , Genómica , Biodiversidad , Genoma
2.
FASEB J ; 33(5): 6115-6128, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30735445

RESUMEN

There is clear evidence for carrier-mediated transport of prolactin into the brain, and it has been widely assumed that prolactin receptors (PRLRs) in the choroid plexus (ChP) might mediate this transport. Using PRLR knockout mice, we recently showed that PRLRs in ChP are not required for prolactin transport into the brain. Hence, the function of PRLR in the ChP remains unknown. PRLR expression is increased in the ChP during lactation, suggesting a possible role in adaptive function of prolactin at this time. To gain insight into prolactin function in the ChP, we have utilized RNA sequencing and NanoString techniques to characterize transcriptional changes in response to differing levels of prolactin at diestrus, during pregnancy, and in lactation. We have observed opposing transcriptional effects of prolactin on the ChP in different physiologic states, being primarily inhibitory during diestrus but stimulatory in lactation. Insulin-like growth factor 2 (Igf2), a highly expressing transcript found in the ChP, showed a 6-fold increase at lactation that returned to baseline on suppression of prolactin levels. These results indicate that Igf2 may be an important downstream mediator of prolactin-induced signaling in the ChP.-Phillipps, H. R., Rand, C. J., Brown, R. S. E., Kokay, I. C., Stanton, J.-A., Grattan, D. R. Prolactin regulation of insulin-like growth factor 2 gene expression in the adult mouse choroid plexus.


Asunto(s)
Encéfalo/metabolismo , Factor II del Crecimiento Similar a la Insulina/genética , Lactancia/metabolismo , Prolactina/metabolismo , Animales , Estro/metabolismo , Femenino , Factor II del Crecimiento Similar a la Insulina/metabolismo , Ratones , Ratones Endogámicos C57BL , Embarazo/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Prolactina/metabolismo
3.
Reproduction ; 157(3): 199-213, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30817311

RESUMEN

The aim of this study was to examine the relationships between gestational nutrition, fetal ovarian development and offspring fertility in female sheep and to highlight the potential mechanisms underlying these relationships. Adult sheep (n = 79) were fed either a maintenance or 0.6 of maintenance plane of nutrition for the first 55 days of gestation and thereafter fed ad libitum. Fetuses were collected for analysis at days 55 and 75 of gestation. Female offspring were monitored from birth until 19 months of age. Effects of restricted nutrition were observed on maternal plasma concentrations of progesterone, creatinine, albumin and Ca2+ at day 55 and creatinine at day 75. Concentrations of metabolic factors and steroid hormones in day 75 fetal plasma were not affected by the restricted maternal plane of nutrition. At day 55 of gestation, fetal ovarian germ cell development was not affected by maternal plane of nutrition. At day 75 of gestation ovaries from fetuses whose dams were exposed to restricted nutrition contained more germ cells but had lower germ cell proliferation rates than controls. For female offspring at 8 months of age, the dams gestational plane of nutrition did not affect the onset of puberty, ovulation rate (OR) and antral follicle counts (AFC). At 19 months of age, ewes from dams exposed to the restricted plane of gestational nutrition had higher OR, AFC and progesterone concentrations while concentrations of FSH were lower. In conclusion, while effects on fertility per se are yet to be determined, a reduced maternal plane of gestational nutrition can improve indicators of fertility in female offspring.


Asunto(s)
Fertilidad/fisiología , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Fenómenos Fisiologicos de la Nutrición Prenatal/fisiología , Maduración Sexual/fisiología , Animales , Calcio/sangre , Creatinina/sangre , Femenino , Desarrollo Fetal , Ovulación/fisiología , Embarazo , Progesterona/sangre , Albúmina Sérica , Ovinos
4.
Reproduction ; 157(1): 13-25, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30394704

RESUMEN

A number of studies have demonstrated effects of gestational undernutrition on fetal ovarian development and postnatal female fertility. However, the mechanism underlying these effects remains elusive. Using a cohort of animals in which altered gestational nutrition affected indicators of postnatal fertility, this study applies RNAseq to fetal ovaries to identify affected genes and pathways that may underlie the relationship between gestational plane of nutrition and postnatal fertility. Pregnant ewes were exposed to either a maintenance diet or 0.6 of maintenance for the first 55 days of gestation followed by an ad libitum diet. Complementary DNA libraries were constructed from 5 to 6 fetal ovaries from each nutritional group at both days 55 and 75 of gestation and sequenced using Ion Proton. Of approximately 16,000 transcripts, 69 genes were differentially expressed at day 55 and 145 genes differentially expressed at day 75. At both gestational ages, genes expressed preferentially in germ cells were common among the differentially expressed genes. Enriched gene ontology terms included ion transport, nucleic acid binding, protease inhibitor activity and carrier proteins of the albumin family. Affected pathways identified by IPA analysis included LXR/RXR activation, FXR/RXR activation, pathways associated with nitric oxide production and citrullination (by NOS1), vitamin C transport and metabolism and REDOX reactions. The data offer some insights into potential mechanisms underlying the relationship between gestational plane of nutrition and postnatal fertility observed in these animals. In particular, the roles of nitric oxide and protease inhibitors in germ cell development are highlighted and warrant further study.


Asunto(s)
Feto/metabolismo , Desnutrición/genética , Ovario/embriología , Ovario/metabolismo , Fenómenos Fisiologicos de la Nutrición Prenatal , Ovinos , Animales , Femenino , Desarrollo Fetal/genética , Feto/embriología , Regulación del Desarrollo de la Expresión Génica , Edad Gestacional , Desnutrición/metabolismo , Embarazo , Complicaciones del Embarazo/genética , Complicaciones del Embarazo/metabolismo , Fenómenos Fisiologicos de la Nutrición Prenatal/genética , Ovinos/embriología , Ovinos/genética , Ovinos/metabolismo
5.
Mol Ecol ; 25(16): 3950-61, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27289078

RESUMEN

While terrestrial megafaunal extinctions have been well characterized worldwide, our understanding of declines in marine megafauna remains limited. Here, we use ancient DNA analyses of prehistoric (<1450-1650 AD) sea lion specimens from New Zealand's isolated Chatham Islands to assess the demographic impacts of human settlement. These data suggest there was a large population of sea lions, unique to the Chatham Islands, at the time of Polynesian settlement. This distinct mitochondrial lineage became rapidly extinct within 200 years due to overhunting, paralleling the extirpation of a similarly large endemic mainland population. Whole mitogenomic analyses confirm substantial intraspecific diversity among prehistoric lineages. Demographic models suggest that even low harvest rates would likely have driven rapid extinction of these lineages. This study indicates that surviving Phocarctos populations are remnants of a once diverse and widespread sea lion assemblage, highlighting dramatic human impacts on endemic marine biodiversity. Our findings also suggest that Phocarctos bycatch in commercial fisheries may contribute to the ongoing population decline.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Extinción Biológica , Leones Marinos/genética , Animales , ADN Antiguo/análisis , ADN Mitocondrial/genética , Explotaciones Pesqueras , Actividades Humanas , Humanos , Islas , Nueva Zelanda
6.
Reprod Fertil Dev ; 27(3): 513-22, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24456710

RESUMEN

Oocytes from prepubertal animals have a reduced ability to undergo normal embryo development and produce viable offspring. The correct quantity, activity and cytoplasmic distribution of oocyte organelles are essential for oocyte maturation, fertilisation and subsequent embryo development. The aim of this study was to quantify the ultrastructural differences between oocytes from prepubertal lamb and adult ewes using electron microscopy and stereology. We also determined whether quantitative polymerase chain reaction (qPCR) methods give comparable estimates of mitochondrial number to stereology. Mean storage vesicle volume was greater in adult compared with lamb oocytes before IVM and decreased during maturation in both adult and lamb oocytes. Mitochondrial volume and number increased in adult oocytes during maturation; however, no increase was observed in lamb oocytes. Mitochondrial DNA copy number measured by qPCR showed no differences between adult and lamb oocytes. A different distribution of mitochondria was observed in lamb oocytes before maturation, while the percentage of hooded mitochondria increased during maturation in adult oocytes and decreased in the lamb. In conclusion, the present study has identified differences in the vesicles and mitochondria between adult and lamb oocytes from ewes that may contribute to reduced developmental competence in prepubertal oocytes.


Asunto(s)
Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Mitocondrias/ultraestructura , Oocitos/ultraestructura , Factores de Edad , Animales , ADN Mitocondrial , Desarrollo Embrionario/fisiología , Femenino , Oocitos/crecimiento & desarrollo , Ovinos
7.
Proc Natl Acad Sci U S A ; 109(45): 18350-4, 2012 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-23091021

RESUMEN

The dispersal of modern humans across the globe began ~65,000 y ago when people first left Africa and culminated with the settlement of East Polynesia, which occurred in the last 1,000 y. With the arrival of Polynesian canoes only 750 y ago, Aotearoa/New Zealand became the last major landmass to be permanently settled by humans. We present here complete mitochondrial genome sequences of the likely founding population of Aotearoa/New Zealand recovered from the archaeological site of Wairau Bar. These data represent complete mitochondrial genome sequences from ancient Polynesian voyagers and provide insights into the genetic diversity of human populations in the Pacific at the time of the settlement of East Polynesia.


Asunto(s)
ADN Mitocondrial/genética , Emigración e Inmigración , Genoma Mitocondrial/genética , Secuencia de Bases , Geografía , Haplotipos/genética , Humanos , Datos de Secuencia Molecular , Nueva Zelanda , Océano Pacífico , Reproducibilidad de los Resultados
8.
BMC Genomics ; 15: 68, 2014 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-24460871

RESUMEN

BACKGROUND: Next-generation DNA sequencing (NGS) technologies have made huge impacts in many fields of biological research, but especially in evolutionary biology. One area where NGS has shown potential is for high-throughput sequencing of complete mtDNA genomes (of humans and other animals). Despite the increasing use of NGS technologies and a better appreciation of their importance in answering biological questions, there remain significant obstacles to the successful implementation of NGS-based projects, especially for new users. RESULTS: Here we present an 'A to Z' protocol for obtaining complete human mitochondrial (mtDNA) genomes - from DNA extraction to consensus sequence. Although designed for use on humans, this protocol could also be used to sequence small, organellar genomes from other species, and also nuclear loci. This protocol includes DNA extraction, PCR amplification, fragmentation of PCR products, barcoding of fragments, sequencing using the 454 GS FLX platform, and a complete bioinformatics pipeline (primer removal, reference-based mapping, output of coverage plots and SNP calling). CONCLUSIONS: All steps in this protocol are designed to be straightforward to implement, especially for researchers who are undertaking next-generation sequencing for the first time. The molecular steps are scalable to large numbers (hundreds) of individuals and all steps post-DNA extraction can be carried out in 96-well plate format. Also, the protocol has been assembled so that individual 'modules' can be swapped out to suit available resources.


Asunto(s)
Biología Computacional/métodos , ADN Mitocondrial/análisis , Genoma Mitocondrial , Secuenciación de Nucleótidos de Alto Rendimiento , Mitocondrias/genética , ADN Mitocondrial/aislamiento & purificación , Humanos , Reacción en Cadena de la Polimerasa , Manejo de Especímenes
9.
N Z Med J ; 137(1596): 43-51, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38843549

RESUMEN

AIM: Cervical cancer is now preventable with human papillomavirus (HPV) vaccination and HPV screening. However, structural health system barriers in rural areas can inhibit screening access. Inequitable access for rural Maori is exacerbated by social determinants and racism. Pro-equity tools, such as self-taken swabs point of care (POC) testing, now exist. This study aimed to investigate whether POC HPV testing and immediate offer of colposcopy by a mobile colposcopy service is possible at a rural community event. METHODS: This case study was a collaboration between a research centre, a women's health bus, a molecular diagnostics company, a Maori health provider and a community charity, and took place prior to the new cervical screening programme introduction at a 2-day community event-a shearathon. Eligible participants were offered a self-taken swab for HPV, which was analysed by POC testing. If high-risk HPV was detected, they were offered an immediate colposcopy. The Maori-centred qualitative component explored women's experiences of the process. RESULTS: Fourteen women undertook a self-test for HPV. High-risk HPV was detected in six women and all were offered immediate colposcopy. Six women were interviewed. All were supportive of the service. Culturally safe staff taking time to put women at ease contributed to acceptability and positive experiences. CONCLUSION: This case study shows that provision of POC HPV testing and colposcopy at a rural community event setting is possible through cross-sector collaboration. This service was acceptable to rural transient workers who face barriers to healthcare in a high-income country.


Asunto(s)
Colposcopía , Infecciones por Papillomavirus , Población Rural , Neoplasias del Cuello Uterino , Humanos , Femenino , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/prevención & control , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Neoplasias del Cuello Uterino/virología , Adulto , Nueva Zelanda , Persona de Mediana Edad , Detección Precoz del Cáncer/métodos , Sistemas de Atención de Punto , Pruebas en el Punto de Atención , Papillomaviridae/aislamiento & purificación , Unidades Móviles de Salud , Nativos de Hawái y Otras Islas del Pacífico , Adulto Joven , Virus del Papiloma Humano
10.
PeerJ ; 12: e16969, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38410796

RESUMEN

Molecular biomonitoring programs increasingly use environmental DNA (eDNA) for detecting targeted species such as marine non-indigenous species (NIS) or endangered species. However, the current molecular detection workflow is cumbersome and time-demanding, and thereby can hinder management efforts and restrict the "opportunity window" for rapid management responses. Here, we describe a direct droplet digital PCR (direct-ddPCR) approach to detect species-specific free-floating extra-cellular eDNA (free-eDNA) signals, i.e., detection of species-specific eDNA without the need for filtration or DNA extraction, with seawater samples. This first proof-of-concept aquarium study was conducted with three distinct marine species: the Mediterranean fanworm Sabella spallanzanii, the ascidian clubbed tunicate Styela clava, and the brown bryozoan Bugula neritina to evaluate the detectability of free-eDNA in seawater. The detectability of targeted free-eDNA was assessed by directly analysing aquarium marine water samples using an optimized species-specific ddPCR assay. The results demonstrated the consistent detection of S. spallanzanii and B. neritina free-eDNA when these organisms were present in high abundance. Once organisms were removed, the free-eDNA signal exponentially declined, noting that free-eDNA persisted between 24-72 h. Results indicate that organism biomass, specimen characteristics (e.g., stress and viability), and species-specific biological differences may influence free-eDNA detectability. This study represents the first step in assessing the feasibility of direct-ddPCR technology for the detection of marine species. Our results provide information that could aid in the development of new technology, such as a field development of ddPCR systems, which could allow for automated continuous monitoring of targeted marine species, enabling point-of-need detection and rapid management responses.


Asunto(s)
Briozoos , Urocordados , Animales , Reacción en Cadena de la Polimerasa/métodos , Monitoreo Biológico , Agua de Mar , Urocordados/genética
11.
Sci Total Environ ; 946: 174354, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38955269

RESUMEN

Passive samplers are enabling the scaling of environmental DNA (eDNA) biomonitoring in our oceans, by circumventing the time-consuming process of water filtration. Designing a novel passive sampler that does not require extensive sample handling time and can be connected to ocean-going vessels without impeding normal underway activities has potential to rapidly upscale global biomonitoring efforts onboard the world's oceanic fleet. Here, we demonstrate the utility of an artificial sponge sampler connected to the continuous pump underway seawater system as a means to enable oceanic biomonitoring. We compared the performance of this passive sampling protocol with standard water filtration at six locations during a research voyage from New Zealand to Antarctica in early 2023. Eukaryote metabarcoding of the mitochondrial COI gene revealed no significant difference in phylogenetic α-diversity between sampling methods and both methods delineated a progressive reduction in number of Zero-Radius Operational Taxonomic Units (ZOTUs) with increased latitudes. While both sampling methods revealed comparable trends in geographical community compositions, distinct clusters were identified for passive samplers and water filtration at each location. Additionally, greater variability between replicates was observed for passive samplers, resulting in an increased estimated level of replication needed to recover 90 % of the biodiversity. Furthermore, traditional water filtration failed to detect three phyla observed by passive samplers and extrapolation analysis estimated passive samplers recover a larger number of ZOTUs compared to water filtration for all six locations. Our results demonstrate the potential of this passive eDNA sampler protocol and highlight areas where this emerging technology could be improved, thereby enabling large-scale offshore marine eDNA biomonitoring by leveraging the world's oceanic fleet without interfering with onboard activities.

12.
Immunogenetics ; 65(8): 619-33, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23686447

RESUMEN

The major histocompatibility complex (MHC) is integral to the vertebrate adaptive immune system. Characterizing diversity at functional MHC genes is invaluable for elucidating patterns of adaptive variation in wild populations, and is particularly interesting in species of conservation concern, which may suffer from reduced genetic diversity and compromised disease resilience. Here, we use next generation sequencing to investigate MHC class II B (MHCIIB) diversity in two sister taxa of New Zealand birds: South Island saddleback (SIS), Philesturnus carunculatus, and North Island saddleback (NIS), Philesturnus rufusater. These two species represent a passerine family outside the more extensively studied Passerida infraorder, and both have experienced historic bottlenecks. We examined exon 2 sequence data from populations that represent the majority of genetic diversity remaining in each species. A high level of locus co-amplification was detected, with from 1 to 4 and 3 to 12 putative alleles per individual for South and North Island birds, respectively. We found strong evidence for historic balancing selection in peptide-binding regions of putative alleles, and we identified a cluster combining non-classical loci and pseudogene sequences from both species, although no sequences were shared between the species. Fewer total alleles and fewer alleles per bird in SIS may be a consequence of their more severe bottleneck history; however, overall nucleotide diversity was similar between the species. Our characterization of MHCIIB diversity in two closely related species of New Zealand saddlebacks provides an important step in understanding the mechanisms shaping MHC diversity in wild, bottlenecked populations.


Asunto(s)
Genes MHC Clase II/genética , Variación Genética , Passeriformes/genética , Polimorfismo Genético , Alelos , Secuencia de Aminoácidos , Animales , Teorema de Bayes , Biología Computacional , Exones , Sitios Genéticos , Datos de Secuencia Molecular , Nueva Zelanda , Passeriformes/clasificación , Filogenia , Seudogenes , Selección Genética
13.
Virol J ; 10: 103, 2013 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-23548106

RESUMEN

BACKGROUND: Enteroviruses are a common cause of human disease and are associated with a wide range of clinical manifestations. Enterovirus 68 is rarely detected yet was reported in many countries in 2010. Here enterovirus 68 was identified for the first time in New Zealand in 2010 and was detected in a further fourteen specimens over a six month period. OBJECTIVES: To genetically characterise enterovirus 68 specimens identified in New Zealand in 2010. STUDY DESIGN: The genome sequence of a New Zealand representative enterovirus 68 isolate was obtained. Ten clinical specimens were analysed by sequencing the VP1 region of the enterovirus 68 genome. RESULTS: Based on sequence analysis of the VP1 region and the full genome of one representative isolate, the New Zealand enterovirus 68 isolates clustered with contemporary enterovirus 68 viruses and do not show any clear distinguishing genetic diversity when compared to other strains. All fifteen specimens showed high similarity with enterovirus 68 by VP1 sequencing. The majority of New Zealand patients suffered from bronchiolitis, were less than two years of age and were of Pacific Island or Maori descent. CONCLUSIONS: We document the rare occurrence of an enterovirus 68 cluster in New Zealand in 2010. These viruses shared similarity with other clusters of enterovirus 68 that occurred globally in 2010. A greater awareness in enterovirus 68 infection may help detect this virus with increased frequency and enable us to better understand the role this strain plays in disease and the reasons behind this global emergence in 2010.


Asunto(s)
Infecciones por Enterovirus/epidemiología , Infecciones por Enterovirus/virología , Enterovirus/genética , Genoma Viral , ARN Viral/genética , Análisis de Secuencia de ADN , Adolescente , Adulto , Niño , Preescolar , Análisis por Conglomerados , Enterovirus/aislamiento & purificación , Femenino , Variación Genética , Humanos , Lactante , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Nueva Zelanda/epidemiología , Filogenia , Homología de Secuencia , Adulto Joven
14.
Methods Mol Biol ; 2588: 75-89, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36418683

RESUMEN

Since our chapter on genome sequencing using the GS-FLX pyrosequencer in the First Edition of this book, significant advances have been made in next-generation DNA sequencing (NGS) technology. Not only has the GS-FLX become extinct, but the more recent introduction and establishment of the so-called third-generation DNA sequencers by Pacific Biosciences (PacBio) and Oxford Nanopore Technologies (ONT) has revolutionized genomics yet again by generating ultra-long (>100,000 basepair) sequence reads concomitant with an incredible reduction in cost per sequenced basepair. Unfortunately, the ultra-high sequence yields of third-generation sequencers are compromised by their inherent sequencing error rates, prompting an alternative sequencing strategy, i.e., a hybrid sequencing strategy, which combines PacBio/ONT primary datasets with complementary datasets generated by mainstream short-read NGS platforms, e.g., Illumina or Ion Torrent. Although the concept of a hybrid sequencing strategy is not new, existing yields and accuracy of ultra-long and short-read sequencing technologies makes such a strategy achievable, resulting in complete genome sequences in one hit. In this chapter, we describe our updated laboratory and bioinformatic protocols that will allow the average research group to obtain complete oral microbial genome sequences assembled from a combination of DNA sequence data generated by NGS and third-generation platforms.


Asunto(s)
Genoma Microbiano , Secuenciación de Nucleótidos de Alto Rendimiento , Secuencia de Bases , Análisis de Secuencia de ADN/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Genómica
15.
FEMS Microbiol Ecol ; 99(7)2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37245057

RESUMEN

Building on a previously developed workflow for rapid and sensitive pathogen detection by qPCR, this work has established a sample treatment strategy that produces consistent quantification efficiencies (QEs) for Campylobacter jejuni against a complex and highly variable sample matrix from a suburban river. The individual treatments most effective at minimizing the inhibitory effects of the sample matrix were pH buffering with HEPES (50 mM, pH 5.7) and addition of the surfactant Tween 20 (2% v/v). Unexpectedly, sample acidification (pH 4-5) resulting from the use of aged Tween 20 that had undergone partial hydrolysis, appeared to play a key role in enhancing QE. This effect could be replicated by direct pH adjustment with dilute hydrochloric acid and may be linked to the solubilization and removal of inhibitory particles at an acidic pH. While the effectiveness of each individual treatment method varied, a combined treatment of either HEPES buffer + Tween 20, or direct pH adjustment + Tween 20, consistently produced QEs of 60%-70% and up to 100%, respectively, over a sampling period of one year. The consistency and scalability of this workflow make it a suitable alternative to culture-based ISO methods for detecting Campylobacter spp.


Asunto(s)
Campylobacter coli , Campylobacter jejuni , Campylobacter jejuni/genética , Polisorbatos , HEPES , Agua
16.
CRISPR J ; 6(4): 316-324, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37439822

RESUMEN

Almost all of Earth's oceans are now impacted by multiple anthropogenic stressors, including the spread of nonindigenous species, harmful algal blooms, and pathogens. Early detection is critical to manage these stressors effectively and to protect marine systems and the ecosystem services they provide. Molecular tools have emerged as a promising solution for marine biomonitoring. One of the latest advancements involves utilizing CRISPR-Cas technology to build programmable, rapid, ultrasensitive, and specific diagnostics. CRISPR-based diagnostics (CRISPR-Dx) has the potential to allow robust, reliable, and cost-effective biomonitoring in near real time. However, several challenges must be overcome before CRISPR-Dx can be established as a mainstream tool for marine biomonitoring. A critical unmet challenge is the need to design, optimize, and experimentally validate CRISPR-Dx assays. Artificial intelligence has recently been presented as a potential approach to tackle this challenge. This perspective synthesizes recent advances in CRISPR-Dx and machine learning modeling approaches, showcasing CRISPR-Dx potential to progress as a rising molecular tool candidate for marine biomonitoring applications.


Asunto(s)
Sistemas CRISPR-Cas , Aprendizaje Profundo , Sistemas CRISPR-Cas/genética , Edición Génica , ARN , Inteligencia Artificial , Monitoreo Biológico , Ecosistema
17.
JMIR Res Protoc ; 12: e51643, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37707939

RESUMEN

BACKGROUND: Maori are the Indigenous people of Aotearoa (New Zealand). Despite global acceptance that cervical cancer is almost entirely preventable through vaccination and screening, wahine Maori (Maori women) are more likely to have cervical cancer and 2.5 times more likely to die from it than non-Maori women. Rural Maori residents diagnosed with cervical cancer have worse outcomes than urban residents. Living in rural Aotearoa means experiencing barriers to appropriate and timely health care, resulting from distance, the lack of community resourcing, and low prioritization of rural needs by the health system and government. These barriers are compounded by the current screening processes and referral pathways that create delays at each step. Screening for high-risk human papillomavirus (hrHPV) and point-of-care (POC) testing are scientific advances used globally to prevent cervical cancer. OBJECTIVE: This study aims to compare acceptability, feasibility, timeliness, referral to, and attendance for colposcopy following hrHPV detection between a community-controlled pathway and standard care. METHODS: This is a cluster randomized crossover trial, with 2 primary care practices (study sites) as clusters. Each site was randomized to implement either pathway 1 or 2, with crossover occurring at 15 months. Pathway 1 (community-controlled pathway) comprises HPV self-testing, 1-hour POC results, face-to-face information, support, and immediate referral to colposcopy for women with a positive test result. Pathway 2 (standard care) comprises HPV self-testing, laboratory analysis, usual results giving, information, support, and standard referral pathways for women with a positive test result. The primary outcome is the proportion of women with hrHPV-positive results having a colposcopy within 20 working days of the HPV test (national performance indicator). Qualitative research will analyze successes and challenges of both pathways from the perspectives of governance groups, clinical staff, women, and their family. This information will directly inform the new National Cervical Screening Program. RESULTS: In the first 15-month period, 743 eligible HPV self-tests were performed: 370 in pathway 1 with POC testing and 373 in pathway 2 with laboratory testing. The positivity rate for hrHPV was 7.3% (54/743). Data collection for the second period, qualitative interviews, and analyses are ongoing. CONCLUSIONS: This Maori-centered study combines quantitative and qualitative research to compare 2 clinical pathways from detection of hrHPV to colposcopy. This protocol draws on rural community practices strengths, successfully engaging Maori from a whanau ora (family wellness) approach including kanohi ki te kanohi (face-to-face), kaiawhina (nonclinical community health workers), and multiple venues for interventions. It will inform the theory and practice of rural models of the use of innovative technology, addressing Maori cervical cancer inequities and facilitating Maori wellness. The findings are anticipated to be applicable to other Indigenous and rural people in high-income countries. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12621000553875; https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12621000553875. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/51643.

18.
PLoS One ; 18(3): e0280643, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36952546

RESUMEN

BACKGROUND: Cervical cancer is caused by high-risk types of human papillomavirus (HPV). Testing for high-risk HPV is a more sensitive screening method than cervical cytology for detecting cervical changes that may lead to cancer. Consistent with recent evidence of efficacy and acceptability, Aotearoa New Zealand plans to introduce HPV testing as the primary approach to screening, replacing cervical cytology, from mid-2023. Any equitable cervical screening programme must be effective across a diverse population, including women that the current programme fails to reach, particularly Maori and those in rural areas. Currently, we do not know the best model for implementing an equitable HPV self-testing screening programme. METHODS: This implementation trial aims to assess whether a universal offer of HPV self-testing (offered to all people eligible for cervical screening) achieves non-inferior screening coverage (equal) to a universal offer of cervical cytology alone (the present programme). The study population is all people aged from 24.5 to 70 years due for cervical screening in a 12-month period (including those whose screening is overdue or who have never had screening). A range of quantitative and qualitative secondary outcomes will be explored, including barriers and facilitators across screening and diagnostic pathways. This study takes place in Te Tai Tokerau/Northland which covers a diverse range of urban and rural areas and has a large Indigenous Maori population. A total of fourteen practices will be involved. Seven practices will offer HPV self-testing universally to approximately 2800 women and will be compared to seven practices providing routine clinical care (offer of cervical cytology) to an approximately equal number of women. DISCUSSION: This trial will answer important questions about how to implement an equitable, high-quality, effective national programme offering HPV self-testing as the primary screening method for cervical cancer prevention. TRIAL REGISTRATION: Prospectively registered with the Australian New Zealand Clinical Trials Registry 07/12/2021: ACTRN12621001675819.


Asunto(s)
Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven , Australia , Detección Precoz del Cáncer/métodos , Virus del Papiloma Humano , Tamizaje Masivo/métodos , Nueva Zelanda/epidemiología , Papillomaviridae , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/prevención & control , Infecciones por Papillomavirus/complicaciones , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Frotis Vaginal
19.
Sci Rep ; 12(1): 621, 2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-35022475

RESUMEN

RNA sequencing offers unprecedented access to the transcriptome. Key to this is the identification and quantification of many different species of RNA from the same sample at the same time. In this study we describe a novel protocol for simultaneous detection of coding and non-coding transcripts using modifications to the Ion Total RNA-Seq kit v2 protocol, with integration of QIASeq FastSelect rRNA removal kit. We report highly consistent sequencing libraries can be produced from both frozen high integrity mouse hippocampal tissue and the more challenging post-mortem human tissue. Removal of rRNA using FastSelect was extremely efficient, resulting in less than 1.5% rRNA content in the final library. We identified > 30,000 unique transcripts from all samples, including protein-coding genes and many species of non-coding RNA, in biologically-relevant proportions. Furthermore, the normalized sequencing read count for select genes significantly negatively correlated with Ct values from qRT-PCR analysis from the same samples. These results indicate that this protocol accurately and consistently identifies and quantifies a wide variety of transcripts simultaneously. The highly efficient rRNA depletion, coupled with minimized sample handling and without complicated and high-loss size selection protocols, makes this protocol useful to researchers wishing to investigate whole transcriptomes.


Asunto(s)
RNA-Seq
20.
Viruses ; 14(2)2022 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-35215963

RESUMEN

SARS-CoV-2, the virus responsible for the COVID-19 pandemic, has wreaked havoc across the globe for the last two years. More than 300 million cases and over 5 million deaths later, we continue battling the first real pandemic of the 21st century. SARS-CoV-2 spread quickly, reaching most countries within the first half of 2020, and New Zealand was not an exception. Here, we describe the first isolation and characterization of SARS-CoV-2 variants during the initial virus outbreak in New Zealand. Patient-derived nasopharyngeal samples were used to inoculate Vero cells and, three to four days later, a cytopathic effect was observed in seven viral cultures. Viral growth kinetics was characterized using Vero and VeroE6/TMPRSS2 cells. The identity of the viruses was verified by RT-qPCR, Western blot, indirect immunofluorescence assays, and electron microscopy. Whole-genome sequences were analyzed using two different yet complementary deep sequencing platforms (MiSeq/Illumina and Ion PGM™/Ion Torrent™), classifying the viruses as SARS-CoV-2 B.55, B.31, B.1, or B.1.369 based on the Pango Lineage nomenclature. All seven SARS-CoV-2 isolates were susceptible to remdesivir (EC50 values from 0.83 to 2.42 µM) and ß-D-N4-hydroxycytidine (molnupiravir, EC50 values from 0.96 to 1.15 µM) but not to favipiravir (>10 µM). Interestingly, four SARS-CoV-2 isolates, carrying the D614G substitution originally associated with increased transmissibility, were more susceptible (2.4-fold) to a commercial monoclonal antibody targeting the spike glycoprotein than the wild-type viruses. Altogether, this seminal work allowed for early access to SARS-CoV-2 isolates in New Zealand, paving the way for numerous clinical and scientific research projects in the country, including the development and validation of diagnostic assays, antiviral strategies, and a national COVID-19 vaccine development program.


Asunto(s)
COVID-19/epidemiología , Genoma Viral , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Adolescente , Adulto , Anciano , Animales , Anticuerpos Monoclonales/farmacología , Antivirales , Chlorocebus aethiops , Estudios de Cohortes , Efecto Citopatogénico Viral , Humanos , Persona de Mediana Edad , Nueva Zelanda/epidemiología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/inmunología , Células Vero , Secuenciación Completa del Genoma , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA