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1.
J Genet ; 1012022.
Artículo en Inglés | MEDLINE | ID: mdl-36330790

RESUMEN

Genome resequencing is an efficient strategy for associating mutant phenotypes with physical genomic loci (Baker 2009). A pilot study of this approach demonstrated that the Neurospora crassa genetic map was critical in narrowing the possible candidate mutations in a strain to a small number in a limited, defined region of the genome (McCluskey et al. 2011). In this study, we utilize a resequencing strategy to identify the mutations underlying the gluc-1 and gluc-2 genes in N. crassa.


Asunto(s)
Neurospora crassa , Neurospora , Neurospora crassa/genética , Proyectos Piloto , Mutación , Análisis de Secuencia de ADN , Fenotipo , Neurospora/genética
2.
Urol Case Rep ; 45: 102222, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36147194

RESUMEN

We present a case of severe acute variceal bleeding in an ileal conduit stoma successfully managed with trans-hepatic trans-portal selective angioembolization as a lifesaving measure. Despite repeated transfusions, the patient's hemoglobin continued to be unstable. The patient underwent transhepatic embolization of ileal stoma varicose veins. Angioembolization was followed up with excision of ileal conduit stoma and creation of cutaneous ureterostomy for definitive treatment management of hemorrhage. In conclusion, trans-hepatic trans-portal embolization is an effective option for management of severe acute variceal bleeding in an ileal conduit stoma as a lifesaving measure and can be followed by excision of the conduit.

3.
Curr Res Microb Sci ; 3: 100117, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35909622

RESUMEN

Using a legacy of genetic mutants of Neurospora crassa, paired with resequencing efforts through JGI, we have identified the gene responsible for the 'scumbo' mutant. This early morphological mutant was described as "Irregular flat, spreading growth with knobby protrusions and abnormal conidiation, but no free conidia. Mycelium usually appears yellowish rather than orange. Female fertile." (Perkins, Radford et al. 2000). Our further investigation has found new insights into the identity and associated functions of scumbo as a ceramide C9 methyltransferase, previously annotated as "similar to cyclopropane-fatty-acyl-phospholipidsynthase", encoded by the gene NCU07859. This enzyme performs a fungal-specific methyl modification of glycosyl-ceramides and has implications for membrane homeostasis and hyphal polarity in filamentous fungi.

4.
PLoS One ; 16(9): e0257823, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34587206

RESUMEN

Fungal hyphal growth and branching are essential traits that allow fungi to spread and proliferate in many environments. This sustained growth is essential for a myriad of applications in health, agriculture, and industry. However, comparisons between different fungi are difficult in the absence of standardized metrics. Here, we used a microfluidic device featuring four different maze patterns to compare the growth velocity and branching frequency of fourteen filamentous fungi. These measurements result from the collective work of several labs in the form of a competition named the "Fungus Olympics." The competing fungi included five ascomycete species (ten strains total), two basidiomycete species, and two zygomycete species. We found that growth velocity within a straight channel varied from 1 to 4 µm/min. We also found that the time to complete mazes when fungal hyphae branched or turned at various angles did not correlate with linear growth velocity. We discovered that fungi in our study used one of two distinct strategies to traverse mazes: high-frequency branching in which all possible paths were explored, and low-frequency branching in which only one or two paths were explored. While the high-frequency branching helped fungi escape mazes with sharp turns faster, the low-frequency turning had a significant advantage in mazes with shallower turns. Future work will more systematically examine these trends.


Asunto(s)
Colaboración de las Masas/métodos , Hongos/crecimiento & desarrollo , Técnicas Analíticas Microfluídicas/instrumentación , Ascomicetos/crecimiento & desarrollo , Basidiomycota/crecimiento & desarrollo , Fenómenos Biológicos , Hongos/clasificación , Hifa/clasificación , Hifa/crecimiento & desarrollo , Especificidad de la Especie
5.
Proc Natl Acad Sci U S A ; 118(26)2021 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-34168079

RESUMEN

Carbohydrate active enzymes (CAZymes) are vital for the lignocellulose-based biorefinery. The development of hypersecreting fungal protein production hosts is therefore a major aim for both academia and industry. However, despite advances in our understanding of their regulation, the number of promising candidate genes for targeted strain engineering remains limited. Here, we resequenced the genome of the classical hypersecreting Neurospora crassa mutant exo-1 and identified the causative point of mutation to reside in the F-box protein-encoding gene, NCU09899. The corresponding deletion strain displayed amylase and invertase activities exceeding those of the carbon catabolite derepressed strain Δcre-1, while glucose repression was still mostly functional in Δexo-1 Surprisingly, RNA sequencing revealed that while plant cell wall degradation genes are broadly misexpressed in Δexo-1, only a small fraction of CAZyme genes and sugar transporters are up-regulated, indicating that EXO-1 affects specific regulatory factors. Aiming to elucidate the underlying mechanism of enzyme hypersecretion, we found the high secretion of amylases and invertase in Δexo-1 to be completely dependent on the transcriptional regulator COL-26. Furthermore, misregulation of COL-26, CRE-1, and cellular carbon and nitrogen metabolism was confirmed by proteomics. Finally, we successfully transferred the hypersecretion trait of the exo-1 disruption by reverse engineering into the industrially deployed fungus Myceliophthora thermophila using CRISPR-Cas9. Our identification of an important F-box protein demonstrates the strength of classical mutants combined with next-generation sequencing to uncover unanticipated candidates for engineering. These data contribute to a more complete understanding of CAZyme regulation and will facilitate targeted engineering of hypersecretion in further organisms of interest.


Asunto(s)
Proteínas F-Box/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Ingeniería Genética , Neurospora crassa/enzimología , Neurospora crassa/genética , Amilasas/metabolismo , Carbono/farmacología , Represión Catabólica , Proteínas F-Box/metabolismo , Proteínas Fúngicas/metabolismo , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Mutación/genética , Nitrógeno/metabolismo , Fenotipo , Secuenciación Completa del Genoma , Xilosa/metabolismo , beta-Fructofuranosidasa/metabolismo
6.
J Fungi (Basel) ; 5(4)2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31817728

RESUMEN

Fungal infections have far-reaching implications that range from severe human disease to a panoply of disruptive agricultural and ecological effects, making it imperative to identify and understand the molecular pathways governing the response to antifungal compounds. In this context, CZT-1 (cell death-activated zinc cluster transcription factor) functions as a master regulator of cell death and drug susceptibility in Neurospora crassa. Here we provide evidence indicating that czt-1 is allelic to acr-3, a previously described locus that we now found to harbor a point mutation in its coding sequence. This nonsynonymous amino acid substitution in a low complexity region of CZT-1/ACR-3 caused a robust gain-of-function that led to reduced sensitivity to acriflavine and staurosporine, and increased expression of the drug efflux pump abc-3. Thus, accumulating evidence shows that CZT-1 is an important broad regulator of the cellular response to various antifungal compounds that appear to share common molecular targets.

8.
J Surg Oncol ; 117(5): 940-946, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29878390

RESUMEN

BACKGROUND AND OBJECTIVES: Ocular melanoma has a predilection for liver metastases. Systemic treatment is ineffective and the optimal regional therapy approach is poorly defined. Isolated hepatic perfusion (IHP) with melphalan has emerged as a viable treatment option, however a subset of patients are not candidates for this treatment. We therefore sought to determine if melphalan could be safely administered via the hepatic artery for these patients. METHODS: A retrospective review of patients treated with hepatic artery infusion (HAI) of melphalan was undertaken. All patients had contraindications to IHP and were without other therapy options. Melphalan infusion was repeated every four weeks with consideration for dose escalation in the absence of toxicity or significant disease progression. RESULTS: Fourteen patients were treated with HAI of melphalan from 2010 to 2015. All patients had hepatic dysfunction or prohibitive tumor volume precluding IHP. There were no procedure-related complications. Three patients (21%) died within 30 days and the median survival was 2.9 months. Elevated baseline bilirubin > 2.5 mg/dL was associated with worse overall survival (0.93 vs 6.3 months, P < 0.05). CONCLUSION: HAI of melphalan is safe and feasible for patients with metastatic ocular melanoma. Further study to determine the optimal utilization of this treatment approach is warranted.


Asunto(s)
Antineoplásicos Alquilantes/administración & dosificación , Quimioterapia del Cáncer por Perfusión Regional , Neoplasias del Ojo/tratamiento farmacológico , Arteria Hepática , Neoplasias Hepáticas/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Melfalán/administración & dosificación , Adulto , Anciano , Progresión de la Enfermedad , Neoplasias del Ojo/patología , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intraarteriales , Neoplasias Hepáticas/secundario , Masculino , Melanoma/patología , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
9.
Gigascience ; 7(5)2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29718202

RESUMEN

Genomic information is essential for taxonomic, phylogenetic, and functional studies to comprehensively decipher the characteristics of microorganisms, to explore microbiomes through metagenomics, and to answer fundamental questions of nature and human life. However, large gaps remain in the available genomic sequencing information published for bacterial and archaeal species, and the gaps are even larger for fungal type strains. The Global Catalogue of Microorganisms (GCM) leads an internationally coordinated effort to sequence type strains and close gaps in the genomic maps of microorganisms. Hence, the GCM aims to promote research by deep-mining genomic data.


Asunto(s)
Bacterias/genética , Hongos/genética , Genómica/métodos , Células Procariotas/metabolismo , Análisis de Secuencia de ADN/métodos , Reproducibilidad de los Resultados
12.
mBio ; 8(4)2017 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-28811341

RESUMEN

The U.S. Culture Collection Network held a meeting to share information about how culture collections are responding to the requirements of the recently enacted Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization to the Convention on Biological Diversity (CBD). The meeting included representatives of many culture collections and other biological collections, the U.S. Department of State, U.S. Department of Agriculture, Secretariat of the CBD, interested scientific societies, and collection groups, including Scientific Collections International and the Global Genome Biodiversity Network. The participants learned about the policies of the United States and other countries regarding access to genetic resources, the definition of genetic resources, and the status of historical materials and genetic sequence information. Key topics included what constitutes access and how the CBD Access and Benefit-Sharing Clearing-House can help guide researchers through the process of obtaining Prior Informed Consent on Mutually Agreed Terms. U.S. scientists and their international collaborators are required to follow the regulations of other countries when working with microbes originally isolated outside the United States, and the local regulations required by the Nagoya Protocol vary by the country of origin of the genetic resource. Managers of diverse living collections in the United States described their holdings and their efforts to provide access to genetic resources. This meeting laid the foundation for cooperation in establishing a set of standard operating procedures for U.S. and international culture collections in response to the Nagoya Protocol.


Asunto(s)
Biodiversidad , Bancos de Muestras Biológicas , Biotecnología/legislación & jurisprudencia , Microbiología Ambiental , Agricultura/legislación & jurisprudencia , Agricultura/organización & administración , Bancos de Muestras Biológicas/legislación & jurisprudencia , Bancos de Muestras Biológicas/organización & administración , Biotecnología/organización & administración , Bases de Datos Genéticas/legislación & jurisprudencia , Modelos Genéticos , Estados Unidos , United States Department of Agriculture
13.
J Biosci ; 42(2): 321-331, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28569255

RESUMEN

While living collections are critical for biological research, support for these foundational infrastructure elements is inconsistent, which makes quality control, regulatory compliance, and reproducibility difficult. In recent years, the Ecological Society of America has hosted several National Science Foundation-sponsored workshops to explore and enhance the sustainability of biological research infrastructure. At the same time, the United States Culture Collection Network has brought together managers of living collections to foster collaboration and information exchange within a specific living collections community. To assess the sustainability of collections, a survey was distributed to collection scientists whose responses provide a benchmark for evaluating the resiliency of these collections. Among the key observations were that plant collections have larger staffing requirements and that living microbe collections were the most vulnerable to retirements or other disruptions. Many higher plant and vertebrate collections have institutional support and several have endowments. Other collections depend on competitive grant support in an era of intense competition for these resources. Opportunities for synergy among living collections depend upon complementing the natural strong engagement with the research communities that depend on these collections with enhanced information sharing, communication, and collective action to keep them sustainable for the future. External efforts by funding agencies and publishers could reinforce the advantages of having professional management of research resources across every discipline.


Asunto(s)
Ambiente , Plantas , Investigación , Bancos de Muestras Biológicas , Microbiología , Estados Unidos
14.
Elife ; 62017 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-28266913

RESUMEN

Many discoveries in the life sciences have been made using material from living stock collections. These collections provide a uniform and stable supply of living organisms and related materials that enhance the reproducibility of research and minimize the need for repetitive calibration. While collections differ in many ways, they all require expertise in maintaining living organisms and good logistical systems for keeping track of stocks and fulfilling requests for specimens. Here, we review some of the contributions made by living stock collections to research across all branches of the tree of life, and outline the challenges they face.


Asunto(s)
Bancos de Muestras Biológicas , Investigación Biomédica/normas , Preservación Biológica/métodos , Estados Unidos
15.
J Vasc Interv Radiol ; 28(5): 704-711, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28169139

RESUMEN

PURPOSE: To evaluate clinical success and time to resolution of intranodal lymphangiography (INL) alone or with thoracic duct embolization (TDE) or thoracic duct disruption (TDD) based on initial effusion volume for postsurgical chylothorax. MATERIALS AND METHODS: Retrospective review was performed of 57 patients (mean age 63 y; 65% male) undergoing INL alone or in conjunction with other percutaneous techniques for postsurgical chylous effusions. INL alone was performed when chylothorax output was ≤ 500 mL/d and no leak was identified during fluoroscopy. RESULTS: INL was technically successful in all patients. There was 1 major and 2 minor complications. Clinical success rate was 71% (40/56). Clinical success rate meeting algorithmic inclusion criteria was 71.4% (5/7) for INL only, 41.7% (5/12) in INL with TDD, and 90.5% (19/21) in INL with TDE. Hazard ratio (HR) of clinical success of INL with TDE versus INL only was not statistically significant (HR 2.3, 95% confidence interval [CI], 0.70-5.87, P = .19). Median time to resolution was 14 days for INL only (95% CI, 0 days to not reached), 7 days for INL with TDD (95% CI, 4 days to not reached), and 3 days for INL with TDE (95% CI, 2 to 5 days) (P = .007). No statistically significant difference in median time to resolution existed between INL with TDE and INL only (P = .04). CONCLUSION: In patients with postsurgical chylothorax, INL alone had similar rates of clinical success and time to resolution compared with INL with TDE when initial effusion volume was ≤ 500 mL/d and no leak was visualized during fluoroscopy.


Asunto(s)
Quilotórax/diagnóstico por imagen , Quilotórax/terapia , Embolización Terapéutica/métodos , Linfografía/métodos , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Fluoroscopía , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Conducto Torácico , Resultado del Tratamiento
16.
Nucleic Acids Res ; 45(D1): D611-D618, 2017 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-28053166

RESUMEN

The World Data Centre for Microorganisms (WDCM) was established 50 years ago as the data center of the World Federation for Culture Collections (WFCC)-Microbial Resource Center (MIRCEN). WDCM aims to provide integrated information services using big data technology for microbial resource centers and microbiologists all over the world. Here, we provide an overview of WDCM including all of its integrated services. Culture Collections Information Worldwide (CCINFO) provides metadata information on 708 culture collections from 72 countries and regions. Global Catalogue of Microorganism (GCM) gathers strain catalogue information and provides a data retrieval, analysis, and visualization system of microbial resources. Currently, GCM includes >368 000 strains from 103 culture collections in 43 countries and regions. Analyzer of Bioresource Citation (ABC) is a data mining tool extracting strain related publications, patents, nucleotide sequences and genome information from public data sources to form a knowledge base. Reference Strain Catalogue (RSC) maintains a database of strains listed in International Standards Organization (ISO) and other international or regional standards. RSC allocates a unique identifier to strains recommended for use in diagnosis and quality control, and hence serves as a valuable cross-platform reference. WDCM provides free access to all these services at www.wdcm.org.


Asunto(s)
Biología Computacional/métodos , Bases de Datos Factuales , Microbiología , Microbiota , Programas Informáticos , Biodiversidad , Minería de Datos , Metagenómica/métodos , Filogenia , Navegador Web , Flujo de Trabajo
17.
Mycology ; 8(2): 67-83, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30123633

RESUMEN

Filamentous fungi have been important as model organisms since the beginning of modern biological inquiry and have benefitted from open data since the earliest genetic maps were shared. From early origins in simple Mendelian genetics of mating types, parasexual genetics of colony colour, and the foundational demonstration of the segregation of a nutritional requirement, the contribution of research systems utilising filamentous fungi has spanned the biochemical genetics era, through the molecular genetics era, and now are at the very foundation of diverse omics approaches to research and development. Fungal model organisms have come from most major taxonomic groups although Ascomycete filamentous fungi have seen the most major sustained effort. In addition to the published material about filamentous fungi, shared molecular tools have found application in every area of fungal biology. Similarly, shared data has contributed to the success of model systems. The scale of data supporting research with filamentous fungi has grown by 10 to 12 orders of magnitude. From genetic to molecular maps, expression databases, and finally genome resources, the open and collaborative nature of the research communities has assured that the rising tide of data has lifted all of the research systems together.

18.
Biopreserv Biobank ; 15(1): 20-30, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27869477

RESUMEN

Formal living collections have unique characteristics that distinguish them from other types of biorepositories. Comprising diverse resources, microbe culture collections, crop and biodiversity plant germplasm collections, and animal germplasm repositories are commonly allied with specific research communities or stakeholder groups. Among living collections, microbial culture collections have very long and unique life histories, with some being older than 100 years. Regulatory, financial, and technical developments have impacted living collections in many ways. International treaty obligations and restrictions on release of genetically modified organisms complicate the activities of living collections. Funding for living collections is a continuing challenge and threatens to create a two-tier system where medically relevant collections are well funded and all other collections are underfunded and hence understaffed. Molecular, genetic, and whole genome sequence analysis of contents of microbes and other living resource collections bring additional value to living collections.


Asunto(s)
Bancos de Muestras Biológicas , Estudios Interdisciplinarios , Investigación , Animales , Bacterias , Biodiversidad , Bancos de Muestras Biológicas/economía , Control Social Formal
19.
Curr Biol ; 26(12): 1577-1584, 2016 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-27238284

RESUMEN

Plants and fungi use light and other signals to regulate development, growth, and metabolism. The fruiting bodies of the fungus Phycomyces blakesleeanus are single cells that react to environmental cues, including light, but the mechanisms are largely unknown [1]. The related fungus Mucor circinelloides is an opportunistic human pathogen that changes its mode of growth upon receipt of signals from the environment to facilitate pathogenesis [2]. Understanding how these organisms respond to environmental cues should provide insights into the mechanisms of sensory perception and signal transduction by a single eukaryotic cell, and their role in pathogenesis. We sequenced the genomes of P. blakesleeanus and M. circinelloides and show that they have been shaped by an extensive genome duplication or, most likely, a whole-genome duplication (WGD), which is rarely observed in fungi [3-6]. We show that the genome duplication has expanded gene families, including those involved in signal transduction, and that duplicated genes have specialized, as evidenced by differences in their regulation by light. The transcriptional response to light varies with the developmental stage and is still observed in a photoreceptor mutant of P. blakesleeanus. A phototropic mutant of P. blakesleeanus with a heterozygous mutation in the photoreceptor gene madA demonstrates that photosensor dosage is important for the magnitude of signal transduction. We conclude that the genome duplication provided the means to improve signal transduction for enhanced perception of environmental signals. Our results will help to understand the role of genome dynamics in the evolution of sensory perception in eukaryotes.


Asunto(s)
Evolución Molecular , Duplicación de Gen , Genoma Fúngico , Mucor/genética , Phycomyces/genética , Transducción de Señal/genética , Luz , Mucor/efectos de la radiación , Familia de Multigenes , Percepción , Phycomyces/efectos de la radiación , Transcripción Genética/efectos de la radiación
20.
Phytopathology ; 106(6): 532-40, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26976729

RESUMEN

The U.S. Culture Collection Network was formed in 2012 by a group of culture collection scientists and stakeholders in order to continue the progress established previously through efforts of an ad hoc group. The network is supported by a Research Coordination Network grant from the U.S. National Science Foundation (NSF) and has the goals of promoting interaction among collections, encouraging the adoption of best practices, and protecting endangered or orphaned collections. After prior meetings to discuss best practices, shared data, and synergy with genome programs, the network held a meeting at the U.S. Department of Agriculture (USDA)-Agricultural Research Service (ARS) National Center for Genetic Resources Preservation (NCGRP) in Fort Collins, Colorado in October 2015 specifically to discuss collections that are vulnerable because of changes in funding programs, or are at risk of loss because of retirement or lack of funding. The meeting allowed collection curators who had already backed up their resources at the USDA NCGRP to visit the site, and brought collection owners, managers, and stakeholders together. Eight formal collections have established off-site backups with the USDA-ARS, ensuring that key material will be preserved for future research. All of the collections with backup at the NCGRP are public distributing collections including U.S. NSF-supported genetic stock centers, USDA-ARS collections, and university-supported collections. Facing the retirement of several pioneering researchers, the community discussed the value of preserving personal research collections and agreed that a mechanism to preserve these valuable collections was essential to any future national culture collection system. Additional input from curators of plant and animal collections emphasized that collections of every kind face similar challenges in developing long-range plans for sustainability.


Asunto(s)
Bacterias/genética , Genómica/organización & administración , Microbiología/organización & administración , Agricultura , Bacterias/clasificación , Bases de Datos Factuales/legislación & jurisprudencia , Estados Unidos , United States Department of Agriculture/organización & administración
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