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1.
J Neurosci ; 44(17)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38453467

RESUMEN

Pain perception arises from the integration of prior expectations with sensory information. Although recent work has demonstrated that treatment expectancy effects (e.g., placebo hypoalgesia) can be explained by a Bayesian integration framework incorporating the precision level of expectations and sensory inputs, the key factor modulating this integration in stimulus expectancy-induced pain modulation remains unclear. In a stimulus expectancy paradigm combining emotion regulation in healthy male and female adults, we found that participants' voluntary reduction in anticipatory anxiety and pleasantness monotonically reduced the magnitude of pain modulation by negative and positive expectations, respectively, indicating a role of emotion. For both types of expectations, Bayesian model comparisons confirmed that an integration model using the respective emotion of expectations and sensory inputs explained stimulus expectancy effects on pain better than using their respective precision. For negative expectations, the role of anxiety is further supported by our fMRI findings that (1) functional coupling within anxiety-processing brain regions (amygdala and anterior cingulate) reflected the integration of expectations with sensory inputs and (2) anxiety appeared to impair the updating of expectations via suppressed prediction error signals in the anterior cingulate, thus perpetuating negative expectancy effects. Regarding positive expectations, their integration with sensory inputs relied on the functional coupling within brain structures processing positive emotion and inhibiting threat responding (medial orbitofrontal cortex and hippocampus). In summary, different from treatment expectancy, pain modulation by stimulus expectancy emanates from emotion-modulated integration of beliefs with sensory evidence and inadequate belief updating.


Asunto(s)
Anticipación Psicológica , Ansiedad , Imagen por Resonancia Magnética , Humanos , Masculino , Femenino , Ansiedad/psicología , Ansiedad/fisiopatología , Adulto , Anticipación Psicológica/fisiología , Adulto Joven , Percepción del Dolor/fisiología , Dolor/psicología , Dolor/fisiopatología , Teorema de Bayes , Emociones/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Encéfalo/fisiología , Placer/fisiología , Mapeo Encefálico
2.
New Phytol ; 241(2): 650-664, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37908121

RESUMEN

Seed germination is a critical trait for the success of direct seeding in rice cultivation. However, the underlying mechanism determining seed germination is largely unknown in rice. Here, we report that NAC transcription factor OsNAC3 positively regulates seed germination of rice. OsNAC3 regulates seed germination involving abscisic acid (ABA) pathway and cell elongation. OsNAC3 can directly bind to the promoter of ABA catabolic gene OsABA8ox1 and cell expansion gene OsEXP4, which consequently activates their expressions during seed germination. We also find that the expression of OsEXP4 is reduced by ABA during seed germination in rice. OsNAC3 regulates seed germination by influencing cell elongation of the embryo through directly affecting OsEXP4 expression and indirectly ABA-medicated OsEXP4 expression. The OsNAC3 elite haplotype is useful for genetic improvement of seed germination, and overexpression of OsNAC3 can significantly increase seed germination. We therefore propose that OsNAC3 is a potential target in breeding of rice varieties with high seed germination for direct seeding cultivation.


Asunto(s)
Ácido Abscísico , Oryza , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Germinación/genética , Oryza/metabolismo , Semillas/genética , Fitomejoramiento , Regulación de la Expresión Génica de las Plantas
3.
J Gen Intern Med ; 39(5): 747-755, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38236317

RESUMEN

BACKGROUND: In patients with new-onset heart failure (HF), coronary artery disease (CAD) testing remains underutilized. Whether widespread CAD testing in patients with new-onset HF leads to improved outcomes remains to be determined. OBJECTIVE: We sought to examine whether CAD testing, and its timing, among patients hospitalized with new-onset HF with reduced ejection fraction (HFrEF), is associated with improved outcomes. DESIGN: Retrospective cohort study. PARTICIPANTS: Adult (≥ 18 years) non-pregnant patients with new-onset HFrEF hospitalized within one of 15 Kaiser Permanente Southern California medical centers between 2016 and 2021. Key exclusion criteria included history of heart transplant, hospice, and a do-not-resuscitate order. MAIN MEASURES: Primary outcome was a composite of HF readmission or all-cause mortality through end of follow-up on 12/31/2022. KEY RESULTS: Among 2729 patients hospitalized with new-onset HFrEF, 1487 (54.5%) received CAD testing. The median age was 66 (56-76) years old, 1722 (63.1%) were male, and 1074 (39.4%) were White. After a median of 1.8 (0.6-3.4) years, the testing group had a reduced risk of HF readmission or all-cause mortality (aHR [95%CI], 0.71 [0.63-0.79]). These results were consistent across subgroups by history of atrial fibrillation, diabetes, renal disease, myocardial infarction, and elevated troponin during hospitalization. In a secondary analysis where CAD testing was further divided to early (received testing before discharge) and late testing (up to 90 days after discharge), there was no difference in late vs early testing (0.97 [0.81-1.16]). CONCLUSIONS: In a contemporary and diverse cohort of patients hospitalized with new-onset HFrEF, CAD testing within 90 days of hospitalization was associated with a lower risk of HF readmission or all-cause mortality. Testing within 90 days after discharge was not associated with worse outcomes.


Asunto(s)
Enfermedad de la Arteria Coronaria , Insuficiencia Cardíaca , Readmisión del Paciente , Humanos , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/diagnóstico , Masculino , Femenino , Readmisión del Paciente/estadística & datos numéricos , Anciano , Persona de Mediana Edad , Estudios Retrospectivos , Enfermedad de la Arteria Coronaria/mortalidad , Enfermedad de la Arteria Coronaria/diagnóstico , California/epidemiología
4.
Fish Shellfish Immunol ; : 109810, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39111606

RESUMEN

Feed terrestrial components can induce intestinal stress in fish, affecting their overall health and growth. Recent studies suggest that seaweed products may improve fish intestinal health. In this experiment, three types of feed were prepared: a basic diet (C group), a diet with 0.2% fucoidan (F group), and a diet with 3% kelp powder (K group). These diets were fed to large yellow croaker (Larimichthys crocea) over an 8-week period. Each feed was randomly assigned to three seawater cages (4.0 m × 4.0 m × 5.0 m) containing 700 fish per cage. The study assessed changes in growth and intestinal health, including intestinal tissue morphology, digestive enzyme activities, expression of immune-related genes, and bacterial community structure. Results showed that incorporating seaweed products into the diet improved the growth and quality traits of large yellow croakers and significantly enhanced their intestinal digestive capacity (P < 0.05). Specifically, the 0.2% fucoidan diet significantly increased the intestinal villus length and the activities of digestive enzymes such as trypsin, lipase, and α-amylase (P < 0.05). The 3% kelp powder diet significantly enhanced the intestinal crypt depth and the activities of trypsin and lipase (P < 0.05). Both seaweed additives significantly enhanced intestinal health by mitigating inflammatory factors. Notably, the control group's biomarkers indicated a high presence of potential pathogenic bacteria, such as Streptococcus, Pseudomonas, Enterococcus, Herbaspirillum, Neisseria, Haemophilus, and Stenotrophomonas. After the addition of seaweed additives, these bacteria were no longer the indicator bacteria, while the abundance of beneficial bacteria like Ligilactobacillus and Lactobacillus increased. Significant reductions in the expression of inflammatory factors (e.g., il-6, tnf-α, ifn-γ in the fucoidan group and il-8 in the kelp powder group) further supported these findings. Our findings suggested that both seaweed additives helped balance intestinal microbial communities and reduce bacterial antigen load. Considering the effects, costs, manufacturing, and nutrition, adding 3% kelp powder to the feed of large yellow croaker might be preferable. This study substantiated the beneficial effects of seaweed on the aquaculture of large yellow croaker, particularly in improving intestinal health. These findings advocated for its wider and more scientifically validated use in fish farming practices.

5.
Biomacromolecules ; 24(2): 943-956, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36645325

RESUMEN

A new potential route to enhance the efficiency of supramolecular polymers for cancer chemotherapy was successfully demonstrated by employing a photosensitive metallosupramolecular polymer (Hg-BU-PPG) containing an oligomeric poly(propylene glycol) backbone and highly sensitive pH-responsive uracil-mercury-uracil (U-Hg-U) bridges. This route holds great promise as a multifunctional bioactive nano-object for development of more efficient and safer cancer chemotherapy. Owing to the formation of uracil photodimers induced by ultraviolet irradiation, Hg-BU-PPG can form a photo-cross-linked structure and spontaneously forms spherical nanoparticles in aqueous solution. The irradiated nanoparticles possess many unique characteristics, such as unique fluorescence behavior, highly sensitive pH-responsiveness, and intriguing phase transition behavior in aqueous solution as well as high structural stability and antihemolytic activity in biological media. More importantly, a series of cellular studies clearly confirmed that the U-Hg-U photo-cross-links in the irradiated nanoparticles substantially enhance their selective cellular uptake by cancer cells via macropinocytosis and the mercury-loaded nanoparticles subsequently induce higher levels of cytotoxicity in cancer cells (compared to non-irradiated nanoparticles), without harming normal cells. These results are mainly attributed to cancer cell microenvironment-triggered release of mercury ions from disassembled nanoparticles, which rapidly induce massive levels of apoptosis in cancer cells. Overall, the pH-sensitive U-Hg-U photo-cross-links within this newly discovered supramolecular system are an indispensable factor that offers a potential path to remarkably enhance the selective therapeutic effects of functional nanoparticles toward cancer cells.


Asunto(s)
Mercurio , Nanopartículas , Neoplasias , Polímeros/química , Portadores de Fármacos/química , Nanopartículas/química , Uracilo/química , Concentración de Iones de Hidrógeno
6.
Cereb Cortex ; 32(7): 1480-1493, 2022 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-34427294

RESUMEN

While detecting somatic stimuli from the external environment, an accurate determination of their spatial and temporal properties is essential for human behavior. Whether and how detection relates to human capacity for somatosensory spatial discrimination (SD) and temporal discrimination (TD) remains unclear. Here, participants underwent functional magnetic resonance imaging scanning when simply detecting vibrotactile stimuli of the leg, judging their location (SD), or deciding their number in time (TD). By conceptualizing tactile discrimination as consisting of detection and determination processes, we found that tactile detection elicited activation specifically involved in SD within the right inferior and superior parietal lobules, 2 regions previously implicated in the control of spatial attention. These 2 regions remained activated in the determination process, during which functional connectivity between these 2 regions predicted individual SD ability. In contrast, tactile detection produced little activation specifically related to TD. Participants' TD ability was implemented in brain regions implicated in coding temporal structures of somatic stimuli (primary somatosensory cortex) and time estimation (anterior cingulate, pre-supplementary motor area, and putamen). Together, our findings indicate a close link between somatosensory detection and SD (but not TD) at the neural level, which aids in explaining why we can promptly respond toward detected somatic stimuli.


Asunto(s)
Corteza Motora , Navegación Espacial , Giro del Cíngulo , Humanos , Imagen por Resonancia Magnética , Lóbulo Parietal , Putamen , Corteza Somatosensorial/diagnóstico por imagen
7.
J Gen Intern Med ; 37(12): 2982-2990, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34545470

RESUMEN

BACKGROUND: Direct oral anticoagulants such as dabigatran are the preferred anticoagulant in treating atrial fibrillation (AF) patients due to their effectiveness and safety. Whether this applies to severely obese patients needs to be determined. OBJECTIVE: To compare the effectiveness and safety of dabigatran with warfarin among AF patients with severe obesity. DESIGN: Retrospective cohort study. PARTICIPANTS: AF patients with a BMI >40kg/m2 or a weight >120kg receiving dabigatran or warfarin between 10/01/2010 and 12/31/2019 in a large integrated health system and followed through 08/01/2020. INTERVENTIONS: Not applicable. MAIN MEASURES: Primary effectiveness outcome was composite thromboembolism including transient ischemic attack, ischemic stroke, or systemic embolism. Primary safety outcome was composite bleeding including gastrointestinal bleeding, intracranial bleeding, or other bleeding. Secondary outcomes included the individual outcomes and all-cause mortality. Propensity score matching (PSM) was performed to create a 1:1 matched cohort and Cox proportional hazards model was used to estimate the hazard ratio (HR) of each outcome for dabigatran users compared to warfarin users. KEY RESULTS: A total of 6848 patients receiving either dabigatran or warfarin were identified. In a 1:1 matched cohort, dabigatran users had a HR of 0.71 (95% confidence interval (CI): 0.56-0.91) for composite thromboembolism, a HR of 1.24 (95%CI: 1.07-1.42) for composite bleeding, and a HR of 0.57 (95% CI: 0.45-0.71) for all-cause mortality when compared to warfarin users. CONCLUSIONS: Among AF patients with a BMI >40kg/m2 or a weight >120kg in a real-world clinical setting, dabigatran was effective in reducing the risk of thromboembolism and mortality but was associated with an increased risk of bleeding when compared to warfarin. Dabigatran may be a reasonable option for AF patients with severe obesity.


Asunto(s)
Fibrilación Atrial , Obesidad Mórbida , Accidente Cerebrovascular , Tromboembolia , Administración Oral , Anticoagulantes/efectos adversos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Estudios de Cohortes , Dabigatrán/efectos adversos , Hemorragia Gastrointestinal/inducido químicamente , Hemorragia Gastrointestinal/epidemiología , Humanos , Obesidad Mórbida/complicaciones , Estudios Retrospectivos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Tromboembolia/epidemiología , Tromboembolia/etiología , Tromboembolia/prevención & control , Resultado del Tratamiento , Warfarina/efectos adversos
8.
J Gen Intern Med ; 37(15): 3973-3978, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36104593

RESUMEN

BACKGROUND: Understanding the implications of disease-specific factors beyond baseline patient characteristics for coronavirus disease 2019 (COVID-19) may allow for identification of indicators for safe hospital discharge. OBJECTIVE: Assess whether disease-specific factors are associated with adverse events post-discharge using a data-driven approach. DESIGN: Retrospective cohort study. SETTING: Fifteen medical centers within Kaiser Permanente Southern California. PARTICIPANTS: Adult patients (n=3508) discharged alive following hospitalization for COVID-19 between 05/01/2020 and 09/30/2020. INTERVENTIONS: None. MAIN MEASURES: Adverse events defined as all-cause readmission or mortality within 14 days of discharge. Least absolute shrinkage and selection operator (LASSO) was used for variable selection and logistic regression was performed to estimate odds ratio (OR) and 95% confidence interval (CI). KEY RESULTS: Four variables including age, Elixhauser index, treatment with remdesivir, and symptom duration at discharge were selected by LASSO. Treatment with remdesivir was inversely associated with adverse events (OR: 0.46 [95%CI: 0.36-0.61]), while symptom duration ≤ 10 days was associated with adverse events (OR: 2.27 [95%CI: 1.79-2.87]) in addition to age (OR: 1.02 [95%CI: 1.01-1.03]) and Elixhauser index (OR: 1.15 [95%CI: 1.11-1.20]). A significant interaction between remdesivir and symptom duration was further observed (p=0.01). The association of remdesivir was stronger among those with symptom duration ≤10 days vs >10 days at discharge (OR: 0.30 [95%CI: 0.19-0.47] vs 0.62 [95%CI: 0.44-0.87]), while the association of symptom duration ≤ 10 days at discharge was weaker among those treated with remdesivir vs those not treated (OR: 1.31 [95%CI: 0.79-2.17] vs 2.71 [95%CI 2.05-3.59]). CONCLUSIONS: Disease-specific factors including treatment with remdesivir, symptom duration, and their interplay may help guide clinical decision making at time of discharge.


Asunto(s)
COVID-19 , Adulto , Humanos , COVID-19/terapia , Alta del Paciente , SARS-CoV-2 , Readmisión del Paciente , Estudios Retrospectivos , Cuidados Posteriores , Hospitales
9.
Emerg Infect Dis ; 27(7): 1944-1948, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34034858

RESUMEN

We report 3 patients in California, USA, who experienced multisystem inflammatory syndrome (MIS) after immunization and severe acute respiratory syndrome coronavirus 2 infection. During the same period, 3 adults who were not vaccinated had MIS develop at a time when ≈7% of the adult patient population had received >1 vaccine.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Vacunas contra la COVID-19 , Humanos , Síndrome , Vacunación
10.
Theor Appl Genet ; 134(12): 4067-4076, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34546380

RESUMEN

KEY MESSAGE: A candidate gene cytochrome b5 for the major QTL qSRMP9 for rice seed reserve mobilization was validated during seed germination using a genome-wide association study approach. Seed reserve mobilization plays important roles in the early seedling growth in rice. However, the genetic basis underlying this process is poorly understood. In this study, the genetic architecture of variation in seed reserve mobilization during seed germination was studied using a genome-wide association study approach in rice. Three quantitative trait loci (QTL) including qSRMP6, qSRMP9, and qSRMP12 for seed reserve mobilization percentage were identified. In which, the candidate gene cytochrome b5 (OsCyb5) for the major QTL qSRMP9 was validated. Disruption of this gene in Oscyb5 mutants reduced the seed reserve mobilization and seedling growth compared with wild-type (WT) in rice. There were no significant differences of grain size, starch, protein and total soluble sugar content in the mature grains between Oscyb5 mutants and WT. However, the α-amylase activity in the germinating seeds of Oscyb5 mutants was significantly decreased compared to that of WT, and then, the starch and sugar mobilization and the glucose accumulation during seed germination were significantly decreased in Oscyb5 mutants. Two elite haplotypes of OsCyb5 associated with the higher seed reserve mobilization percentage and its elite single nucleotide polymorphism variations were mainly existed in the INDICA and AUS accessions. The natural variation of OsCyb5 contributing to seed reserve mobilization might be useful for the future rice breeding.


Asunto(s)
Citocromos b5/genética , Germinación/genética , Oryza/genética , Semillas/fisiología , Alelos , Estudios de Asociación Genética , Haplotipos , Oryza/fisiología , Sitios de Carácter Cuantitativo , Plantones
11.
BMC Genomics ; 21(1): 530, 2020 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-32736518

RESUMEN

BACKGROUND: Studies of leaf shape development and plant stature have made important contributions to the fields of plant breeding and developmental biology. The optimization of leaf morphology and plant height to improve lodging resistance and photosynthetic efficiency, increase planting density and yield, and facilitate mechanized harvesting is a desirable goal in Brassica napus. RESULTS: Here, we investigated a B. napus germplasm resource exhibiting up-curled leaves and a semi-dwarf stature. In progeny populations derived from NJAU5737 and Zhongshuang 11 (ZS11), we found that the up-curled leaf trait was controlled by a dominant locus, BnUC2. We then fine mapped the BnUC2 locus onto an 83.19-kb interval on chromosome A05 using single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers. We further determined that BnUC2 was a major plant height QTL that explained approximately 70% of the phenotypic variation in two BC5F3 family populations derived from NJAU5737 and ZS11. This result implies that BnUC2 was also responsible for the observed semi-dwarf stature. The fine mapping interval of BnUC2 contained five genes, two of which, BnaA05g16700D (BnaA05.IAA2) and BnaA05g16720D, were revealed by comparative sequencing to be mutated in NJAU5737. This result suggests that the candidate gene mutation (BnaA05g16700D, encoding Aux/IAA2 proteins) in the conserved Degron motif GWPPV (P63S) was responsible for the BnUC2 locus. In addition, investigation of agronomic traits in a segregated population indicated that plant height, main inflorescence length, and branching height were significantly reduced by BnUC2, whereas yield was not significantly altered. The determination of the photosynthetic efficiency showed that the BnUC2 locus was beneficial to improve the photosynthetic efficiency. Our findings may provide an effective foundation for plant type breeding in B. napus. CONCLUSIONS: Using SNP and SSR markers, a dominant locus (BnUC2) related to up-curled leaves and semi-dwarf stature in B. napus has been fine mapped onto an 83.19-kb interval of chromosome A05 containing five genes. The BnaA05.IAA2 is inferred to be the candidate gene responsible for the BnUC2 locus.


Asunto(s)
Brassica napus , Brassica napus/genética , Mapeo Cromosómico , Fenotipo , Fitomejoramiento , Hojas de la Planta/genética
12.
Proc Natl Acad Sci U S A ; 114(37): 9918-9923, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28847949

RESUMEN

Climate-induced forest mortality is being increasingly observed throughout the globe. Alarmingly, it is expected to exacerbate under climate change due to shifting precipitation patterns and rising air temperature. However, the impact of concomitant changes in atmospheric humidity and CO2 concentration through their influence on stomatal kinetics remains a subject of debate and inquiry. By using a dynamic soil-plant-atmosphere model, mortality risks associated with hydraulic failure and stomatal closure for 13 temperate and tropical forest biomes across the globe are analyzed. The mortality risk is evaluated in response to both individual and combined changes in precipitation amounts and their seasonal distribution, mean air temperature, specific humidity, and atmospheric CO2 concentration. Model results show that the risk is predicted to significantly increase due to changes in precipitation and air temperature regime for the period 2050-2069. However, this increase may largely get alleviated by concurrent increases in atmospheric specific humidity and CO2 concentration. The increase in mortality risk is expected to be higher for needleleaf forests than for broadleaf forests, as a result of disparity in hydraulic traits. These findings will facilitate decisions about intervention and management of different forest types under changing climate.


Asunto(s)
Bosques , Transpiración de Plantas/fisiología , Atmósfera/análisis , Dióxido de Carbono/análisis , Cambio Climático , Simulación por Computador , Sequías , Ecosistema , Humedad , Estomas de Plantas/fisiología , Lluvia , Suelo/química , Temperatura , Árboles/fisiología , Agua/fisiología
13.
BMC Plant Biol ; 19(1): 324, 2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31324149

RESUMEN

BACKGROUND: Leaf shape development research is important because leaf shapes such as moderate curling can help to improve light energy utilization efficiency. Leaf growth and development includes initiation of the leaf primordia and polar differentiation of the proximal-distal, adaxial-abaxial, and centrolateral axes. Changes in leaf adaxial-abaxial polarity formation, auxin synthesis and signaling pathways, and development of sclerenchyma and cuticle can cause abnormal leaf shapes such as up-curling leaf. Although many genes related to leaf shape development have been reported, the detailed mechanism of leaf development is still unclear. Here, we report an up-curling leaf mutant plant from our Brassica napus germplasm. We studied its inheritance, mapped the up-curling leaf locus BnUC1, built near-isogenic lines for the Bnuc1 mutant, and evaluated the effect of the dominant leaf curl locus on leaf photosynthetic efficiency and agronomic traits. RESULTS: The up-curling trait was controlled by one dominant locus in a progeny population derived from NJAU5734 and Zhongshuang 11 (ZS11). This BnUC1 locus was mapped in an interval of 2732.549 kb on the A05 chromosome of B. napus using Illumina Brassica 60 K Bead Chip Array. To fine map BnUC1, we designed 201 simple sequence repeat (SSR) primers covering the mapping interval. Among them, 16 polymorphic primers that narrowed the mapping interval to 54.8 kb were detected using a BC6F2 family population with 654 individuals. We found six annotated genes in the mapping interval using the B. napus reference genome, including BnaA05g18250D and BnaA05g18290D, which bioinformatics and gene expression analyses predicted may be responsible for leaf up-curling. The up-curling leaf trait had negative effects on the agronomic traits of 30 randomly selected individuals from the BC6F2 population. The near-isogenic line of the up-curling leaf (ZS11-UC1) was constructed to evaluate the effect of BnUC1 on photosynthetic efficiency. The results indicated that the up-curling leaf trait locus was beneficial to improve the photosynthetic efficiency. CONCLUSIONS: An up-curling leaf mutant Bnuc1 was controlled by one dominant locus BnUC1. This locus had positive effects on photosynthetic efficiency, negative effects on some agronomic traits, and may help to increase planting density in B. napus.


Asunto(s)
Brassica napus/genética , Genes de Plantas/genética , Hojas de la Planta/anatomía & histología , Brassica napus/anatomía & histología , Clorofila/metabolismo , Mapeo Cromosómico , Genes de Plantas/fisiología , Sitios Genéticos , Mutación , Fotosíntesis , Reacción en Cadena en Tiempo Real de la Polimerasa
14.
Plant Cell Environ ; 42(11): 3121-3139, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31124152

RESUMEN

The ability to transport water through tall stems hydraulically limits stomatal conductance (gs ), thereby constraining photosynthesis and growth. However, some plants are able to minimize this height-related decrease in gs , regardless of path length. We hypothesized that kudzu (Pueraria lobata) prevents strong declines in gs with height through appreciable structural and hydraulic compensative alterations. We observed only a 12% decline in maximum gs along 15-m-long stems and were able to model this empirical trend. Increasing resistance with transport distance was not compensated by increasing sapwood-to-leaf-area ratio. Compensating for increasing leaf area by adjusting the driving force would require water potential reaching -1.9 MPa, far below the wilting point (-1.2 MPa). The negative effect of stem length was compensated for by decreasing petiole hydraulic resistance and by increasing stem sapwood area and water storage, with capacitive discharge representing 8-12% of the water flux. In addition, large lateral (petiole, leaves) relative to axial hydraulic resistance helped improve water flow distribution to top leaves. These results indicate that gs of distal leaves can be similar to that of basal leaves, provided that resistance is highest in petioles, and sufficient amounts of water storage can be used to subsidize the transpiration stream.


Asunto(s)
Hojas de la Planta/crecimiento & desarrollo , Tallos de la Planta/crecimiento & desarrollo , Estomas de Plantas/crecimiento & desarrollo , Transpiración de Plantas/fisiología , Pueraria/crecimiento & desarrollo , Agua/fisiología , Transporte Biológico , Dióxido de Carbono/metabolismo , Gravitación , Fotosíntesis/fisiología , Hojas de la Planta/metabolismo , Tallos de la Planta/anatomía & histología , Estomas de Plantas/anatomía & histología , Estomas de Plantas/fisiología , Pueraria/anatomía & histología , Pueraria/fisiología , Agua/metabolismo
16.
J Proteome Res ; 17(5): 1761-1772, 2018 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-29693398

RESUMEN

Moderate leaf rolling is important in ideotype breeding, as it improves photosynthetic efficiency and therefore increases crop yields. To understand the regulatory network of leaf rolling in Brassica napus, a down-curved leaf mutant ( Bndcl1) has been investigated. Physiological analyses indicated that the chlorophyll contents and antioxidant enzyme activities were remarkably increased and the photosynthetic performance was significantly improved in Bndcl1. Consistent with these findings, 943 differentially accumulated proteins (DAPs) were identified in the Bndcl1 mutant and its wild-type plants using iTRAQ-based comparative proteomic analyses. Enrichment analysis of proteins with higher abundance in Bndcl1 revealed that the functional category "photosynthesis" was significantly overrepresented. Moreover, proteins associated with oxidative stress response and photosystem II repairing were also up-accumulated in Bndcl1, which might help the mutant to sustain the photosynthetic efficiency under unfavorable conditions. Histological observation showed that the mutant displayed defects in adaxial-abaxial patterning. Important DAPs associated with leaf polarity establishment were detected in Bndcl1, including ribosomal proteins, proteins involved in post-transcriptional gene silencing, and proteins related to brassinosteroid. Together, our findings may help clarify the mechanisms underlying leaf rolling and its physiological effects on plants and may facilitate ideotype breeding in Brassica napus.


Asunto(s)
Brassica napus/fisiología , Hojas de la Planta/fisiología , Proteínas de Plantas/fisiología , Proteómica , Antioxidantes , Brassica napus/genética , Clorofila , Regulación de la Expresión Génica de las Plantas , Estrés Oxidativo , Fotosíntesis , Complejo de Proteína del Fotosistema II , Proteínas de Plantas/genética
17.
Plant Cell Environ ; 41(12): 2718-2730, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30071137

RESUMEN

Plant xylem response to drought is routinely represented by a vulnerability curve (VC). Despite the significance of VCs, the connection between anatomy and tissue-level hydraulic response to drought remains a subject of inquiry. We present a numerical model of water flow in flowering plant xylem that combines current knowledge on diffuse-porous anatomy and embolism spread to explore this connection. The model produces xylem networks and uses different parameterizations of intervessel connection vulnerability to embolism spread: the Young-Laplace equation and pit membrane stretching. Its purpose is upscaling processes occurring on the microscopic length scales, such as embolism propagation through pit membranes, to obtain tissue-scale hydraulics. The terminal branch VC of Acer glabrum was successfully reproduced relying only on real observations of xylem tissue anatomy. A sensitivity analysis shows that hydraulic performance and VC shape and location along the water tension axis are heavily dependent on anatomy. The main result is that the linkage between pit-scale and vessel-scale anatomical characters, along with xylem network topology, affects VCs significantly. This work underscores the importance of stepping up research related to the three-dimensional network structure of xylem tissues. The proposed model's versatility makes it an important tool to explore similar future questions.


Asunto(s)
Madera/anatomía & histología , Xilema/fisiología , Acer/anatomía & histología , Acer/fisiología , Deshidratación , Modelos Biológicos , Árboles/anatomía & histología , Árboles/fisiología , Agua/metabolismo
18.
New Phytol ; 213(3): 1093-1106, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27870064

RESUMEN

In addition to buffering plants from water stress during severe droughts, plant water storage (PWS) alters many features of the spatio-temporal dynamics of water movement in the soil-plant system. How PWS impacts water dynamics and drought resilience is explored using a multi-layer porous media model. The model numerically resolves soil-plant hydrodynamics by coupling them to leaf-level gas exchange and soil-root interfacial layers. Novel features of the model are the considerations of a coordinated relationship between stomatal aperture variation and whole-system hydraulics and of the effects of PWS and nocturnal transpiration (Fe,night) on hydraulic redistribution (HR) in the soil. The model results suggest that daytime PWS usage and Fe,night generate a residual water potential gradient (Δψp,night) along the plant vascular system overnight. This Δψp,night represents a non-negligible competing sink strength that diminishes the significance of HR. Considering the co-occurrence of PWS usage and HR during a single extended dry-down, a wide range of plant attributes and environmental/soil conditions selected to enhance or suppress plant drought resilience is discussed. When compared with HR, model calculations suggest that increased root water influx into plant conducting-tissues overnight maintains a more favorable water status at the leaf, thereby delaying the onset of drought stress.


Asunto(s)
Suelo/química , Agua/metabolismo , Carbono/metabolismo , Modelos Biológicos , Raíces de Plantas/fisiología , Estomas de Plantas/fisiología , Transpiración de Plantas/fisiología , Xilema/fisiología
19.
J Hosp Med ; 19(2): 116-119, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38169081

RESUMEN

There is concern that sodium-glucose cotransporter-2 inhibitors during hospitalization for acute heart failure (aHF) may precipitate diabetic ketoacidosis (DKA). A retrospective study of all hospitalization encounters for aHF defined by a primary HF International Classification of Diseases (ICD)-10 code in 15 Kaiser Permanente Southern California medical centers hospitalized between January 1, 2021 and August 31, 2023 was performed to describe rates of DKA with empagliflozin use. DKA was defined by the presence of either a DKA ICD-10 code or ketoacidosis lab criteria (bicarbonate <18 mmol/L and urine ketone 1+ or more or elevated serum beta-hydroxybutyrate within 12 h) during hospitalization. Among 21,630 hospital encounters (15,518 patients) for aHF, 1678 (8%) had empagliflozin use. There were 2 (0.1%) probable DKA cases in empagliflozin encounters and 15 (0.1%) in nonexposed encounters. These rates were similar when stratified by diabetes status and ejection fraction. Empagliflozin may be safe during aHF hospitalization.


Asunto(s)
Compuestos de Bencidrilo , Diabetes Mellitus , Cetoacidosis Diabética , Glucósidos , Insuficiencia Cardíaca , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Cetoacidosis Diabética/tratamiento farmacológico , Cetoacidosis Diabética/epidemiología , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Estudios Retrospectivos , Hospitalización , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/epidemiología
20.
Am J Manag Care ; 30(1): e1-e3, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38271567

RESUMEN

Transitional care management (TCM) services after hospital discharge are critical for continuity of care, and the COVID-19 pandemic accelerated the shift to telehealth modes of delivery. This study examined the shift from face-to-face to telehealth care around the start of the pandemic (April-July 2020) compared with the same months in 2019 and 2021 and the corresponding 30-day readmission rates. We compared the rates of face-to-face and telehealth TCM as well as face-to-face and telehealth non-TCM services and observed a dramatic shift to telehealth in 2020 with a slight drop-off in 2021. For TCM services specifically, face-to-face visits made up nearly 90% of visits in 2019, whereas telehealth made up the vast majority in 2020 and 2021 at 97.5% and 84.9%, respectively. Over the same time periods, 30-day readmission rates remained steady at 10% along with no changes in 30-day mortality. Among those who completed TCM visits, 30-day readmission rates remained between 8% and 9% and 30-day mortality remained below 1%. These data indicate that this dramatic systemwide shift from face-to-face to telehealth TCM was not accompanied by concurrent changes in either 30-day readmission or mortality rates. Although the findings may be subject to ecologic bias, the data at hand did not allow for reliable estimation of differences in effects of patient-level service delivery type on readmission risk or mortality due to the extremely low volume of face-to-face visits during the pandemic periods. Future research would be needed to conduct such comparisons.


Asunto(s)
COVID-19 , Telemedicina , Cuidado de Transición , Humanos , COVID-19/epidemiología , Readmisión del Paciente , Pandemias
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