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1.
Cell Genom ; 4(3): 100519, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38484704

RESUMEN

The diversity of CRISPR systems, coupled with scientific ingenuity, has led to an explosion of applications; however, to test newly described innovations in their model systems, researchers typically embark on cumbersome, one-off cloning projects to generate custom reagents that are optimized for their biological questions. Here, we leverage Golden Gate cloning to create the Fragmid toolkit, a modular set of CRISPR cassettes and delivery technologies, along with a web portal, resulting in a combinatorial platform that enables scalable vector assembly within days. We further demonstrate that multiple CRISPR technologies can be assessed in parallel in a pooled screening format using this resource, enabling the rapid optimization of both novel technologies and cellular models. These results establish Fragmid as a robust system for the rapid design of CRISPR vectors, and we anticipate that this assembly approach will be broadly useful for systematic development, comparison, and dissemination of CRISPR technologies.


Asunto(s)
Sistemas CRISPR-Cas , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Sistemas CRISPR-Cas/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Vectores Genéticos/genética
2.
bioRxiv ; 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37961518

RESUMEN

The diversity of CRISPR systems, coupled with scientific ingenuity, has led to an explosion of applications; however, to test newly-described innovations in their model systems, researchers typically embark on cumbersome, one-off cloning projects to generate custom reagents that are optimized for their biological questions. Here, we leverage Golden Gate cloning to create the Fragmid toolkit, a modular set of CRISPR cassettes and delivery technologies, along with a web portal, resulting in a combinatorial platform that enables scalable vector assembly within days. We further demonstrate that multiple CRISPR technologies can be assessed in parallel in a pooled screening format using this resource, enabling the rapid optimization of both novel technologies and cellular models. These results establish Fragmid as a robust system for the rapid design of CRISPR vectors, and we anticipate that this assembly approach will be broadly useful for systematic development, comparison, and dissemination of CRISPR technologies.

4.
J Nutr Educ Behav ; 55(2): 125-134, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36764794

RESUMEN

OBJECTIVE: To assess African Americans' satisfaction with Supplemental Nutrition Assistance Program-Education (SNAP-Ed) in Louisiana. METHODS: African American facilitators conducted 5 focus group discussions with 25 African American SNAP-Ed participants according to issues identified by African American SNAP-Ed implementers in Louisiana. Focus group discussion transcripts were coded independently using inductive and in vivo coding by 2 members of the research team. RESULTS: Participants viewed lessons as race-neutral and thought they should include more information about African American history and culture. Participants also noted a lack of engagement with the African American community and stressed the need for the program to employ African American staff. However, participants thought the information was important for African Americans in the context of medical issues faced by their community. CONCLUSIONS AND IMPLICATIONS: Findings indicate that SNAP-Ed in Louisiana be modified to address African American food history and culture, additional African American staff and better engagement with the African American community.


Asunto(s)
Negro o Afroamericano , Asistencia Alimentaria , Humanos , Pobreza , Alimentos
5.
Nutr Res Rev ; 36(1): 155-174, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35022096

RESUMEN

African Americans experience high rates of obesity and food insecurity in part due to structural racism, or overlapping discriminatory systems and practices in housing, education, employment, health care and other settings. Nutrition education and nutrition-focused policy, systems and environmental changes may be able to address structural racism in the food environment. This scoping review aimed to summarise the available literature regarding nutrition interventions for African Americans that address structural racism in the food environment and compare them with the 'Getting to Equity in Obesity Prevention' framework of suggested interventions. An electronic literature search was conducted with the assistance of a research librarian encompassing six databases: MEDLINE, PyscINFO, Agricola, ERIC, SocINDEX and ProQuest Dissertations & Theses. A total of thirty sources were identified detailing interventions addressing structural barriers to healthy eating. The majority of nutrition interventions addressing structural racism consisted of policy, systems and/or environmental changes in combination with nutrition education, strategies focused on proximal causes of racial health disparities. Only two articles each targeted the 'reduce deterrents' and 'improve social and economic resources' aspects of the framework, interventions which may be better suited to addressing structural racism in the food environment. Because African Americans experience high rates of obesity and food insecurity and encounter structural barriers to healthy eating in the food environment, researchers and public health professionals should address this gap in the literature.


Asunto(s)
Alimentos , Racismo Sistemático , Humanos
6.
Nutr Res Rev ; 36(2): 320-339, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35514108

RESUMEN

Nutrition education and policy, systems and environmental (PSE) change interventions may be able to address food insecurity and obesity, conditions which are disproportionately experienced by African Americans. Work that seeks to address these disparities and advance social justice should uplift and learn from participant voices, particularly from marginalised groups. This scoping review aimed to summarise the available literature describing African Americans' perceptions of and experiences participating in nutrition interventions. We conducted an electronic literature search with the assistance of a research librarian which encompassed six databases (MEDLINE, PyscINFO, Agricola, ERIC, SocINDEX and ProQuest Dissertations & Theses) and identified thirty-five sources meeting our inclusion criteria. The majority of studies assessing African Americans' satisfaction with interventions examined educational interventions alone, and about half of the included studies assessed satisfaction through quantitative methods alone. The only studies which found participants to be dissatisfied with interventions used qualitative methods and examined interventions providing education alone. Future work should evaluate African Americans' experience with nutrition-focused PSE changes, interventions which may be better able to address racial disparities in obesity and food insecurity. Nutrition educators working with African Americans should also consider evaluating future interventions using qualitative inquiry, to obtain an in-depth understanding of participant experiences with interventions.


Asunto(s)
Negro o Afroamericano , Obesidad , Humanos , Investigación Cualitativa , Obesidad/prevención & control
7.
Artículo en Inglés | MEDLINE | ID: mdl-36141494

RESUMEN

In recent years, national and local efforts to improve diet and health in the United States have stressed the importance of nutrition security, which emphasizes consistent access to foods and beverages that promote health and prevent disease among all individuals. At the core of this endeavor is fruit and vegetable (FV) consumption, a dietary practice that is integral to attaining and sustaining a healthy diet. Unfortunately, significant inequities in FV accessibility, purchasing, and consumption exist, particularly among populations that are socially and economically disadvantaged. To achieve nutrition and health equity in the United States, the field must center the goal of nutrition security and initiatives that aim to increase FV consumption, specifically, in future work. The International Journal of Environmental Research and Public Health (IJERPH) Special Issue titled "Nutrition and Health Equity: Revisiting the Importance of Fruit and Vegetable Availability, Purchasing, and Consumption" features several scholarly publications from experts conducting timely research on these topics. In this commentary, we (1) summarize the U.S.-based literature on inequities in FV accessibility, purchasing, and consumption, (2) describe how the contributions to this IJERPH special issue can advance nutrition security and health equity, and (3) outline future research questions from our perspective.


Asunto(s)
Equidad en Salud , Verduras , Dieta , Conducta Alimentaria , Frutas , Promoción de la Salud , Humanos , Estados Unidos
8.
Am J Clin Nutr ; 113(5): 1209-1220, 2021 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-33693468

RESUMEN

BACKGROUND: Replacement of conventional staples with biofortified or industrially fortified staples in household diets may increase maternal breast milk retinol content and vitamin A intakes from complementary foods, improving infant total body stores (TBS) of vitamin A. OBJECTIVES: To determine whether biofortified or industrially fortified maize consumption by Zambian women and their breastfeeding infants could improve milk retinol concentration and infant TBS. METHODS: We randomly assigned 255 lactating women and their 9-mo-old infants to a 90-d intervention providing 0 µg retinol equivalents (RE)/d as conventional maize or ∼315 µg RE/d to mothers and ∼55 µg RE/d to infants as provitamin A carotenoid-biofortified maize or retinyl palmitate-fortified maize. Outcomes were TBS, measured by retinol isotope dilution in infants (primary), and breast milk retinol, measured by HPLC in women (secondary). RESULTS: The intervention groups were comparable at baseline. Loss to follow-up was 10% (n = 230 mother-infant pairs). Women consumed 92% of the intended 287 g/d and infants consumed 82% of the intended 50 g/d maize. The baseline geometric mean (GM) milk retinol concentration was 1.57 µmol/L (95% CI: 1.45, 1.69 µmol/L), and 24% of women had milk retinol <1.05 µmol/L. While mean milk retinol did not change in the biofortified arm (ß: 0.11; 95% CI: -0.02, 0.24), the intervention reduced low milk retinol (RR: 0.42; 95% CI: 0.21, 0.85). Fortified maize increased mean milk retinol (ß: 0.17; 95% CI: 0.04, 0.30) and reduced the prevalence of low milk retinol (RR: 0.46; 95% CI: 0.25, 0.82). The baseline GM TBS was 178 µmol (95% CI: 166, 191 µmol). This increased by 24 µmol (± 136) over the 90-d intervention period, irrespective of treatment group. CONCLUSIONS: Both biofortified and fortified maize consumption improved milk retinol concentration. This did not translate into greater infant TBS, most likely due to adequate TBS at baseline. This trial was registered at clinicaltrials.gov as NCT02804490.


Asunto(s)
Biofortificación , Diterpenos/administración & dosificación , Leche Humana/química , Ésteres de Retinilo/administración & dosificación , Vitamina A/administración & dosificación , Vitamina A/química , Zea mays/genética , Adulto , Lactancia Materna , Estudios de Cohortes , Femenino , Alimentos Fortificados , Humanos , Lactante , Vitamina A/metabolismo , Zambia
9.
J Interv Card Electrophysiol ; 60(1): 69-75, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32048116

RESUMEN

PURPOSE: Current guidelines recommend complete extraction of cardiovascular implantable electronic devices (CIEDs) in the case of persistent or recurrent fungemia without other identifiable sources, though supporting evidence is lacking. We sought to evaluate the prognosis of patients with candidemia and CIEDs. METHODS: Twelve consecutive patients (54 ± 12 years, 8 male) with CIED and concurrent candidemia were reviewed. RESULTS: At the time of diagnosis with candidemia, seven patients were immunocompromised, six were on long-term antibacterial therapy, two were intravenous drug users, four were on chronic hemodialysis, and six had a central venous catheter. Four patients were confirmed as definite CIED infection as vegetation was visible on lead by echocardiogram. The other 8 patients were considered possible CIED infection with candidemia of unknown focus. All patients with visible vegetation underwent CIED removal without complications, and other patients were initially managed non-operatively. After 1 year of follow-up, 7 patients had died and at extended follow-up, all patients without lead removal died while 3 of 4 patients with lead extraction survived. Of note, 50% of deaths in the patients without lead removal were associated with fungal sepsis. CONCLUSIONS: Candida fungemia is associated with a high mortality. CIED removal should be an early consideration in these patients even if lead vegetations are not seen.


Asunto(s)
Candidemia , Desfibriladores Implantables , Marcapaso Artificial , Infecciones Relacionadas con Prótesis , Candidemia/diagnóstico por imagen , Desfibriladores Implantables/efectos adversos , Remoción de Dispositivos , Electrónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
Artículo en Inglés | MEDLINE | ID: mdl-32722214

RESUMEN

Food insecurity in rural settings is complex and not fully understood, especially from the perspective of low-income and Black residents. The goal of this study was to use qualitative methods to better understand experiences with food access and perceptions of the food environment among low-income, predominately Black rural Louisiana residents in the United States. Data were collected from focus group discussions (FGD) and focus group intake forms. Study participants were all rural residents eligible to receive at least one nutrition assistance program. FGD questions focused on perceptions of the food environment, with an emphasis on food access. Participants (n = 44) were predominately Black and female. Over half (n = 25) reported running out of food before the end of the month. Major themes included: store choice, outshopping, methods of acquiring foods other than the grocery store, and food insecurity. Concerns around price, quality, and transportation emerged as factors negatively impacting food security. Understanding residents' perceptions and experiences is necessary to inform contextually appropriate and feasible policy and practice interventions that address the physical environment and social conditions that shape the broader physical food environment in order to achieve equitable food access and food security.


Asunto(s)
Negro o Afroamericano , Abastecimiento de Alimentos , Pobreza , Población Rural , Femenino , Humanos , Louisiana , Masculino , Estados Unidos
11.
Infect Control Hosp Epidemiol ; 41(8): 921-925, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32539873

RESUMEN

OBJECTIVE: To evaluate the impact of a pharmacist-driven Staphylococcus aureus bacteremia (SAB) safety bundle supported by leadership and to compare compliance before and after implementation. DESIGN: Retrospective cohort study with descriptive and before-and-after analyses. SETTING: Tertiary-care academic medical center. PATIENTS: All patients with documented SAB, regardless of the source of infection, were included. Patients transitioned to palliative care were excluded from before-and-after analysis. METHODS: A pharmacist-driven safety bundle including documented clearance of bacteremia, echocardiography, removal of central venous catheters, and targeted intravenous therapy of at least 2 weeks duration was implemented in November 2015 and was supported by leadership with stepwise escalation for nonresponse. A descriptive analysis of all patients with SAB during the study period included pharmacy interventions, acceptance rates, and escalation rates. A pre-post implementation analysis of 100 sequential patients compared bundle compliance and descriptive parameters. RESULTS: Overall, 391 interventions were made in the 20-month period following implementation, including 20 "good saves" avoiding potentially major adverse events. No statistically significant differences in complete bundle compliance were detected between the periods (74% vs 84%; P = .08). However, we detected a significant increase in echocardiography after the bundle was implemented (83% vs 94%; P = .02) and fewer patients received suboptimal definitive therapy after the bundle was implemented (10% vs 3%; P = .045). CONCLUSIONS: This pharmacist-driven SAB safety bundle with leadership support showed improvement in process measures, which may have prevented major adverse events, even with available infectious diseases (ID) consultation. It provides a critical safety net for institutions without mandatory ID consultation or with limited antimicrobial stewardship resources.


Asunto(s)
Bacteriemia , Staphylococcus aureus , Algoritmos , Bacteriemia/tratamiento farmacológico , Bacteriemia/prevención & control , Humanos , Farmacéuticos , Estudios Retrospectivos , Resultado del Tratamiento
12.
Infect Control Hosp Epidemiol ; 41(1): 102-112, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31727195

RESUMEN

Antimicrobial stewardship improves patient care and reduces antimicrobial resistance, inappropriate use, and adverse outcomes. Despite high-profile mandates for antimicrobial stewardship programs across the healthcare continuum, descriptive data, and recommendations for dedicated resources, including appropriate physician, pharmacist, data analytics, and administrative staffing support, are not robust. This review summarizes the current literature on antimicrobial stewardship staffing and calls for the development of minimum staffing recommendations.


Asunto(s)
Programas de Optimización del Uso de los Antimicrobianos/organización & administración , Admisión y Programación de Personal , Humanos , Infecciones/tratamiento farmacológico , Infecciones/microbiología , Farmacéuticos , Médicos , Recursos Humanos
14.
Open Forum Infect Dis ; 5(10): ofy185, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30320147

RESUMEN

BACKGROUND: Vancomycin-resistant enterococcus (VRE) causes substantial health care-associated infection with increasing reports of resistance to daptomycin or linezolid. We conducted a case-control study reporting 81 cases of daptomycin and linezolid-nonsusceptible VRE (DLVRE), a resistance pattern not previously reported. METHODS: We reviewed VRE isolates from June 2010 through June 2015 for nonsusceptibility to both daptomycin (minimum inhibitory concentration [MIC] > 4) and linezolid (MIC ≥ 4). We matched cases by year to control patients with VRE susceptible to both daptomycin and linezolid and performed retrospective chart review to gather risk factor and outcome data. RESULTS: We identified 81 DLVRE cases. Resistance to both daptomycin and linezolid was more common than resistance to either agent individually. Compared with susceptible VRE, DLVRE was more likely to present as bacteremia without focus (P < 0.01), with DLVRE patients more likely to be immune suppressed (P = .04), to be neutropenic (P = .03), or to have had an invasive procedure in the prior 30 days (P = .04). Any antibiotic exposure over the prior 30 days conferred a 4-fold increased risk for DLVRE (odds ratio [OR], 4.25; 95% confidence interval [CI], 1.43-12.63; P = .01); multivariate analysis implicated daptomycin days of therapy (DOT) over the past year as a specific risk factor (OR, 1.10; 95% CI, 1.01-1.19; P = .03). DLVRE cases had longer hospitalizations (P = .04) but no increased risk for in-hospital death. CONCLUSIONS: DLVRE is an emerging multidrug-resistant pathogen associated with immune suppression, neutropenia, and recent invasive procedure. Prior antibiotic exposure, specifically daptomycin exposure, confers risk for acquisition of DLVRE.

15.
Infect Control Hosp Epidemiol ; 39(6): 637-643, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29770752

RESUMEN

OBJECTIVEVentilator bundles encompass practices that reduce the risk of ventilator complications, including ventilator-associated pneumonia. The impact of ventilator bundles on the risk of developing ventilator-associated events (VAEs) is unknown. We sought to determine whether decreased compliance to the ventilator bundle increases the risk for VAE development.DESIGNNested case-control study.SETTINGThis study was conducted at 6 adult intensive care units at an academic tertiary-care center in Tennessee.PATIENTSIn total, 273 patients with VAEs were randomly matched in a 1:4 ratio to controls by mechanical ventilation duration and ICU type.METHODSControls were selected from the primary study population at risk for a VAE after being mechanically ventilated for the same number of days as a specified case. Using conditional logistic regression analysis, overall cumulative compliance, and compliance with individual components of the bundle in the 3 and 7 days prior to VAE development (or the control match day) were examined.RESULTSOverall bundle compliance at 3 days (odds ratio [OR], 1.15; P=.34) and 7 days prior to VAE diagnosis (OR, 0.96; P=.83) were not associated with VAE development. This finding did not change when limiting the outcome to infection-related ventilator-associated complications (IVACs) and after adjusting for age and gender. In the examination of compliance with specific bundle components increased compliance with chlorhexidine oral care was associated with increased risk of VAE development in all analyses.CONCLUSIONSVentilator bundle compliance was not associated with a reduced risk for VAEs. Higher compliance with chlorhexidine oral care was associated with a greater risk for VAE development.Infect Control Hosp Epidemiol 2018;39:637-643.


Asunto(s)
Infección Hospitalaria/prevención & control , Adhesión a Directriz , Control de Infecciones/métodos , Neumonía Asociada al Ventilador/prevención & control , Ventiladores Mecánicos/efectos adversos , Centros Médicos Académicos , Anciano , Estudios de Casos y Controles , Clorhexidina/uso terapéutico , Desinfectantes/uso terapéutico , Femenino , Adhesión a Directriz/estadística & datos numéricos , Humanos , Unidades de Cuidados Intensivos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neumonía Asociada al Ventilador/epidemiología , Factores de Riesgo , Tennessee/epidemiología
16.
Artículo en Inglés | MEDLINE | ID: mdl-29530850

RESUMEN

A woman in her late 60s with disseminated histoplasmosis was treated with posaconazole because first-line therapies were not tolerated. She subsequently presented with decompensated heart failure, hypertension, and hypokalemia. Laboratory tests revealed low renin and aldosterone levels. A potential mechanism is inhibition of the enzyme 11ß-hydroxysteroid dehydrogenase 2, with resultant apparent mineralocorticoid excess.


Asunto(s)
Antifúngicos/efectos adversos , Insuficiencia Cardíaca/inducido químicamente , Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Hiperaldosteronismo/inducido químicamente , Hipertensión/inducido químicamente , Hipopotasemia/inducido químicamente , Síndrome de Exceso Aparente de Mineralocorticoides/inducido químicamente , Triazoles/efectos adversos , Anciano , Antifúngicos/uso terapéutico , Histoplasmosis/tratamiento farmacológico , Humanos , Hiperaldosteronismo/diagnóstico , Síndrome de Exceso Aparente de Mineralocorticoides/diagnóstico , Triazoles/uso terapéutico , Voriconazol/uso terapéutico , Síndrome de Exceso Aparente de Mineralocorticoides
17.
Food Nutr Bull ; 38(4): 594-598, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28978232

RESUMEN

BACKGROUND: Industrial food fortification is a major strategy to improve dietary micronutrient intakes and prevent deficiencies. Zambia introduced mandatory sugar fortification with vitamin A, at a target of 10 mg/kg, in 1998. Representative surveys conducted since that time do not support marked improvement in vitamin A status. OBJECTIVE: To describe vitamin A concentrations in retail sugar, as well as vendor practices, perceptions of fortified foods, and sugar use practices. METHODS: We conducted a census of sugar vendors in one Zambian community, capturing information on vendors, available brands and packaging options, and storage conditions. We purchased all brands and package types of sugar available at each vendor. In a 15% subsample, we conducted semi-structured interviews with vendor-consumer pairs. We tested 50% of sugar samples at random for vitamin A using an iCheck portable fluorimeter. RESULTS: The distribution of vitamin A in sugar in market samples was highly skewed, with a median of 3.1 mg/kg (25th-75th percentiles: 1.8-5.5) and a range from 0.2 to 29.9 mg/kg. Only 11.3% of samples met the 10 mg/kg statutory requirement. Sugar was primarily repackaged and sold in small quantities, with rapid turnover of stocks. Perceptions of fortification by vendors and consumers were generally positive. CONCLUSIONS: Vitamin A in fortified sugar fell well below statutory requirements. Our data point to challenges at regional depot and/or poor adherence to fortification standards at the factory level. A renewed commitment to monitoring and enforcement will be required for Zambia to benefit from a food fortification strategy.


Asunto(s)
Industria de Alimentos/normas , Alimentos Fortificados , Azúcares , Deficiencia de Vitamina A/prevención & control , Vitamina A/administración & dosificación , Benchmarking , Humanos , Zambia
18.
Cell Rep ; 14(8): 1892-900, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26904938

RESUMEN

Visual motion information is computed by parallel On and Off pathways in the retina, which lead to On and Off types of starburst amacrine cells (SACs). The approximate mirror symmetry between this pair of cell types suggests that On and Off pathways might compute motion using analogous mechanisms. To test this idea, we reconstructed On SACs and On bipolar cells (BCs) from serial electron microscopic images of a mouse retina. We defined a new On BC type in the course of classifying On BCs. Through quantitative contact analysis, we found evidence that sustained and transient On BC types are wired to On SAC dendrites at different distances from the SAC soma, mirroring our previous wiring diagram for the Off BC-SAC circuit. Our finding is consistent with the hypothesis that On and Off pathways contain parallel correlation-type motion detectors.


Asunto(s)
Células Amacrinas/fisiología , Dendritas/fisiología , Células Bipolares de la Retina/fisiología , Células Ganglionares de la Retina/fisiología , Sinapsis/fisiología , Células Amacrinas/ultraestructura , Animales , Dendritas/ultraestructura , Procesamiento de Imagen Asistido por Computador , Ratones , Microscopía Electrónica , Reconocimiento Visual de Modelos/fisiología , Células Bipolares de la Retina/ultraestructura , Células Ganglionares de la Retina/ultraestructura , Sinapsis/ultraestructura
19.
Nature ; 509(7500): 331-336, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24805243

RESUMEN

How does the mammalian retina detect motion? This classic problem in visual neuroscience has remained unsolved for 50 years. In search of clues, here we reconstruct Off-type starburst amacrine cells (SACs) and bipolar cells (BCs) in serial electron microscopic images with help from EyeWire, an online community of 'citizen neuroscientists'. On the basis of quantitative analyses of contact area and branch depth in the retina, we find evidence that one BC type prefers to wire with a SAC dendrite near the SAC soma, whereas another BC type prefers to wire far from the soma. The near type is known to lag the far type in time of visual response. A mathematical model shows how such 'space-time wiring specificity' could endow SAC dendrites with receptive fields that are oriented in space-time and therefore respond selectively to stimuli that move in the outward direction from the soma.


Asunto(s)
Mapeo Encefálico , Modelos Neurológicos , Vías Nerviosas/fisiología , Retina/citología , Retina/fisiología , Análisis Espacio-Temporal , Células Amacrinas/citología , Células Amacrinas/fisiología , Células Amacrinas/ultraestructura , Animales , Inteligencia Artificial , Colaboración de las Masas , Dendritas/metabolismo , Ratones , Movimiento (Física) , Terminales Presinápticos/metabolismo , Células Bipolares de la Retina/citología , Células Bipolares de la Retina/fisiología , Células Bipolares de la Retina/ultraestructura
20.
Plant Dis ; 92(6): 966-972, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30769728

RESUMEN

Phytophthora spp. represent a serious threat to agricultural and ecological systems. Many novel Phytophthora spp. have been reported in recent years, which is indicative of our limited understanding of the ecology and diversity of Phytophthora spp. in nature. Systematic cataloging of genotypic and phenotypic information on isolates of previously described species serves as a baseline for identification, classification, and risk assessment of new Phytophthora isolates. The Phytophthora Database (PD) was established to catalog such data in a web-accessible and searchable format. To support the identification of new Phytophthora isolates via comparison of their sequences at one or more loci with the corresponding sequences derived from the isolates archived in the PD, we generated and deposited sequence data from more than 1,500 isolates representing the known diversity in the genus. Data search and analysis tools in the PD include BLAST, Phyloviewer (a program for building phylogenetic trees using sequences of selected isolates), and Virtual Gel (a program for generating expected restriction patterns for given sequences). The PD also provides a customized means of storing and sharing data via the web. The PD serves as a model that easily can be adopted to develop databases for other important pathogen groups.

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