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1.
Plant Cell ; 36(6): 2065-2085, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38511271

RESUMEN

Plants exhibit an enormous phenotypic plasticity to adjust to changing environmental conditions. For this purpose, they have evolved mechanisms to detect and measure biotic and abiotic factors in their surroundings. Phytochrome B exhibits a dual function, since it serves as a photoreceptor for red and far-red light as well as a thermosensor. In 1999, it was first reported that phytochromes not only translocate into the nucleus but also form subnuclear foci upon irradiation by red light. It took more than 10 years until these phytochrome speckles received their name; these foci were coined photobodies to describe unique phytochrome-containing subnuclear domains that are regulated by light. Since their initial discovery, there has been much speculation about the significance and function of photobodies. Their presumed roles range from pure experimental artifacts to waste deposits or signaling hubs. In this review, we summarize the newest findings about the meaning of phyB photobodies for light and temperature signaling. Recent studies have established that phyB photobodies are formed by liquid-liquid phase separation via multivalent interactions and that they provide diverse functions as biochemical hotspots to regulate gene expression on multiple levels.


Asunto(s)
Fitocromo B , Fitocromo B/metabolismo , Fitocromo B/genética , Luz , Transducción de Señal , Temperatura
2.
Plant Mol Biol ; 114(4): 85, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38995464

RESUMEN

Phenylpropanoids, a class of specialized metabolites, play crucial roles in plant growth and stress adaptation and include diverse phenolic compounds such as flavonoids. Phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) are essential enzymes functioning at the entry points of general phenylpropanoid biosynthesis and flavonoid biosynthesis, respectively. In Arabidopsis, PAL and CHS are turned over through ubiquitination-dependent proteasomal degradation. Specific kelch domain-containing F-Box (KFB) proteins as components of ubiquitin E3 ligase directly interact with PAL or CHS, leading to polyubiquitinated PAL and CHS, which in turn influences phenylpropanoid and flavonoid production. Although phenylpropanoids are vital for tomato nutritional value and stress responses, the post-translational regulation of PAL and CHS in tomato remains unknown. We identified 31 putative KFB-encoding genes in the tomato genome. Our homology analysis and phylogenetic study predicted four PAL-interacting SlKFBs, while SlKFB18 was identified as the sole candidate for the CHS-interacting KFB. Consistent with their homolog function, the predicted four PAL-interacting SlKFBs function in PAL degradation. Surprisingly, SlKFB18 did not interact with tomato CHS and the overexpression or knocking out of SlKFB18 did not affect phenylpropanoid contents in tomato transgenic lines, suggesting its irreverence with flavonoid metabolism. Our study successfully discovered the post-translational regulatory machinery of PALs in tomato while highlighting the limitation of relying solely on a homology-based approach to predict interacting partners of F-box proteins.


Asunto(s)
Aciltransferasas , Proteínas F-Box , Regulación de la Expresión Génica de las Plantas , Fenilanina Amoníaco-Liasa , Filogenia , Proteínas de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Fenilanina Amoníaco-Liasa/metabolismo , Fenilanina Amoníaco-Liasa/genética , Aciltransferasas/metabolismo , Aciltransferasas/genética , Flavonoides/metabolismo , Flavonoides/biosíntesis , Plantas Modificadas Genéticamente , Propanoles/metabolismo
3.
BMC Surg ; 21(1): 39, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33461536

RESUMEN

BACKGROUND: Trans-sacral epiduroscopic laser decompression (SELD) using slender epiduroscope and a holmium YAG laser is one of the minimally invasive surgical options for lumbar disc herniation. However, the learning curve of SELD and the effect of surgical proficiency on clinical outcome have not yet been established. We investigated patients with lumbar disc herniation undergoing SELD to report the clinical outcome and learning curve. METHODS: Retrospective analysis of clinical outcome and learning curve were performed at a single center from clinical data collected from November 2015 to November 2018. A total of 82 patients who underwent single-level SELD for lumbar disc herniation with a minimum follow-up of 6.0 months were enrolled. Based on the findings that the cut-off of familiarity was 20 cases according to the cumulative study of operation time, patients were allocated to two groups: early group (n = 20) and late group (n = 62). The surgical, clinical, and radiological outcomes were retrospectively evaluated between the two groups to analyze the learning curve of SELD. RESULTS: According to linear and log regression analyses, the operation time was obtained by the formula: operation time = 58.825-(0.181 × [case number]) (p < 0.001). The mean operation time was significantly different between the two groups (mean 56.95 min; 95% confidence interval [CI], 49.12-64.78 in the early group versus mean 45.34 min; 95% CI, 42.45-48.22 in the late group; p = 0.008, non-parametric Mann-Whitney U test). Baseline characteristics, including demographic data, clinical factors, and findings of preoperative magnetic resonance imaging, did not differ between the two groups. Also, there was no significant difference in terms of surgical outcomes, including complication and failure rates, as well as clinical and radiological outcomes between the two groups. CONCLUSION: The learning curve of SELD was not as steep as that of other minimally invasive spinal surgery techniques, and the experience of surgery was not an influencing factor for outcome variation.


Asunto(s)
Descompresión Quirúrgica/métodos , Espacio Epidural/cirugía , Desplazamiento del Disco Intervertebral/cirugía , Rayos Láser , Curva de Aprendizaje , Adulto , Anciano , Femenino , Humanos , Degeneración del Disco Intervertebral , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Dolor de la Región Lumbar/etiología , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Tempo Operativo , Estudios Retrospectivos , Resultado del Tratamiento
4.
J Nanosci Nanotechnol ; 19(9): 5441-5447, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30961694

RESUMEN

Gold nanoparticles (GNPs) are utilized as diagnostic and therapeutic tools to detect and treat human disease. Researchers in the field of nanotoxicity are working to determine the physicochemical properties of nanoparticles that lead to toxicity in an effort to establish safe design rules. In this study, we performed the MTT and terminal transferase dUTP nick end labeling (TUNEL) assays to verify the cytotoxicity of GNPs on rat brain tissue and human neural progenitor cells (NPCs). As results, we observed that GNPs induced apoptosis in NPCs. NPCs were markedly damaged following the administration of 200 µM and 2 mM GNPs, whereas 2 µM GNPs showed slightly increased damage relative to that of the control. In addition, TUNEL-positive cells were densely distributed at regions surrounding the GNP injection site in the brain 7 days after the GNPs injection. During long-term GNPs exposure, TUNEL-positive cells were rarely observed in the cerebral cortex. In this study, we observed that apoptosis increased in proportion to GNP concentrations in the brain and in cultivated NPCs. These result suggest that large GNPs (<100 nm) are toxic and that the cytotoxicity increased as the concentration of GNPs increased in NPCs or in the brain.


Asunto(s)
Nanopartículas del Metal , Células-Madre Neurales , Animales , Encéfalo , Oro/toxicidad , Humanos , Nanopartículas del Metal/toxicidad , Tamaño de la Partícula , Ratas
5.
Acta Neurochir (Wien) ; 161(10): 2003-2012, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31073785

RESUMEN

BACKGROUND: Trevo Provue stent retriever with visible struts under fluoroscopy may be useful in identifying the optimal position and expansion of the stent during the procedure. This study aimed to demonstrate and analyze changes in the segmental diameter of a radio-opaque stent retriever after deployment according to recanalization results, and its relationship with the angle of the occluded segment of the middle cerebral artery (MCA). METHODS: Forty-one patients who underwent mechanical thrombectomy using a Trevo stent retriever were divided into two groups according to Thrombolysis in Cerebral Infarction (TICI) score (TICI 0-2a and TICI 2b/3). The proximal (Pt), middle (Mt), and distal diameter (Dt) of the deployed stent, at three post-deployment waiting times (t = 0, 3, and 5 min), were measured, and ratios of Mt to Pt (Mt/Pt) and of Mt to Dt (Mt/Dt) were calculated. RESULTS: TICI 2b/3 was achieved in 31 patients (75.6%) and TICI 0-2a in 10 patients (24.4%). In the TICI 2b/3 group, both changes of Mt/Pt (P < 0.001) and Mt/Dt (P = 0.001) until 3 min were significant and all Mt/Pt (each P < 0.01), M3/D3 (P = 0.014), and M5/D5 (P = 0.012) were significantly larger than those in the TICI 0-2a group. The angle of the MCA was significantly correlated with Mt/Pt and Mt/Dt (P < 0.001). CONCLUSION: The diameter of the stent retriever after deployment was associated with the recanalization results in mechanical thrombectomy following MCA occlusion.


Asunto(s)
Infarto de la Arteria Cerebral Media/cirugía , Arteria Cerebral Media/cirugía , Complicaciones Posoperatorias/epidemiología , Trombectomía/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Stents/efectos adversos , Trombectomía/efectos adversos , Trombectomía/instrumentación
6.
Pediatr Neurosurg ; 54(6): 386-393, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31600754

RESUMEN

BACKGROUND: The aim of this study was to retrospectively evaluate and analyze the relationships between head circumference percentile (HCP), lumbar puncture pressure (LPP), and cerebrospinal fluid (CSF) space. METHODS: The 88 patients were divided into 3 age groups (group 1, up to 12 months; group 2, 12-36 months; group 3, 36-72 months). RESULTS: In group 1 (n = 40), there was a significant positive correlation of the HCP with the LPP (r =0.414, p =0.008), Evans ratio (r =0.365, p =0.021), and thickness of subdural hygroma (SDHG; r =0.403, p =0.010). Group 2 (n = 29) revealed a significant positive correlation between the LPP and the thickness of SDHG (r =0.459, p =0.012). Group 3 (n = 19) showed no significant correlation among these factors. Overall, age was related with SDHG thickness both in infants and toddlers, while HCP was related with LPP, Evans ratio, and SDHG thickness only in infants, and LPP was related with SDHG thickness only in toddlers. CONCLUSION: We suggest that increased cerebrospinal space and pressure may result in compensatory enlargement of head circumference only in the infant period, and the SDHG thickness decreases with age during the infant and toddler phases.


Asunto(s)
Adaptación Fisiológica , Cefalometría , Ventrículos Cerebrales/diagnóstico por imagen , Presión Intracraneal , Punción Espinal , Factores de Edad , Líquido Cefalorraquídeo , Preescolar , Discapacidades del Desarrollo/complicaciones , Femenino , Humanos , Lactante , Recién Nacido , Hipertensión Intracraneal/complicaciones , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Convulsiones/complicaciones , Efusión Subdural/diagnóstico por imagen , Tomografía Computarizada por Rayos X
7.
Plant Physiol ; 173(4): 1953-1966, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28232584

RESUMEN

HEMERA (HMR) is a nuclear and plastidial dual-targeted protein. While it functions in the nucleus as a transcriptional coactivator in phytochrome signaling to regulate a distinct set of light-responsive, growth-relevant genes, in plastids it is known as pTAC12, which associates with the plastid-encoded RNA polymerase, and is essential for inducing the plastomic photosynthetic genes and initiating chloroplast biogenesis. However, the mechanism of targeting HMR to the nucleus and plastids is still poorly understood. Here, we show that HMR can be directly imported into chloroplasts through a transit peptide residing in the N-terminal 50 amino acids. Upon cleavage of the transit peptide and additional proteolytic processing, mature HMR, which begins from Lys-58, retains its biochemical properties in phytochrome signaling. Unexpectedly, expression of mature HMR failed to rescue not only the plastidial but also the nuclear defects of the hmr mutant. This is because the predicted nuclear localization signals of HMR are nonfunctional, and therefore mature HMR is unable to accumulate in either plastids or the nucleus. Surprisingly, fusing the transit peptide of the small subunit of Rubisco with mature HMR rescues both its plastidial and nuclear localization and functions. These results, combined with the observation that the nuclear form of HMR has the same reduced molecular mass as plastidial HMR, support a retrograde protein translocation mechanism in which HMR is targeted first to plastids, processed to the mature form, and then relocated to the nucleus.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Núcleo Celular/genética , Plastidios/genética , Factores de Transcripción/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Regulación de la Expresión Génica de las Plantas , Immunoblotting , Microscopía Confocal , Mutación , Fitocromo/genética , Plantas Modificadas Genéticamente , Plastidios/metabolismo , Transporte de Proteínas/genética , Proteolisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ribulosa-Bifosfato Carboxilasa/genética , Ribulosa-Bifosfato Carboxilasa/metabolismo , Transducción de Señal/genética , Factores de Transcripción/metabolismo
8.
Brain Inj ; 30(4): 407-413, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26910852

RESUMEN

OBJECTIVE: The aim of this study was to investigate the regional cerebral metabolism related to growth hormone deficiency (GHD) after traumatic brain injury (TBI) using F-18 fluorodeoxyglucose positron emission tomography (F-18 FDG PET) images. METHODS: Twenty-three patients with diffuse axonal injury following TBI were enrolled. They underwent brain F-18 FDG PET study and an insulin tolerance test (ITT). According to the results of ITT, they were divided into two groups: patients with GHD and subjects with TBI but normal Growth Hormone (GH). Voxel-based statistical analysis was performed and the regional cerebral glucose metabolism shown on F-18 FDG PET from 10 patients with GHD was compared with those from 13 patients without GHD. Analysis was performed using SPM2 to identify regions where decreased changes in regional cerebral glucose metabolism were significantly related to GHD. RESULTS: Compared with subjects with TBI but normal GH, patients with GHD after TBI showed decreased cerebral glucose metabolism in the Left superior frontal gyrus, Right angular gyrus, Right superior temporal gyrus, Left inferior temporal gyrus, Left anterior and middle cingulate gyrus and Right anterior and middle cingulate gyrus. (puncorrected < 0.005). CONCLUSIONS: The findings are suggestive of the brain region influenced by GHD. These cortical areas are involved in regulation of intellectual function, executive function and working memory.


Asunto(s)
Lesiones Traumáticas del Encéfalo/patología , Encéfalo/metabolismo , Glucosa/metabolismo , Hormona del Crecimiento/deficiencia , Adulto , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Trastornos del Conocimiento/diagnóstico por imagen , Trastornos del Conocimiento/etiología , Lesión Axonal Difusa/diagnóstico por imagen , Lesión Axonal Difusa/etiología , Femenino , Fluorodesoxiglucosa F18/farmacocinética , Escala de Coma de Glasgow , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones , Adulto Joven
9.
Biotechnol Bioeng ; 112(2): 288-96, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25182602

RESUMEN

Microalgae cultures show wide range of pH depending on the availability of light and CO2 for their strain specific photosynthesis. Thus, the modulation of light irradiation and CO2 supply can be applied for the pH control of microalgae cultures. The optimal pH of Ettlia sp. YC001, for phototrophic growth and auto-flocculation was investigated by controlling light irradiation and 10% CO2 supply. Ettlia sp. YC001 showed the highest biomass productivity, 96.7 mg L(-1) d(-1) , at pH 8.5. The flocculating activity of Ettlia sp. YC001 showed a sigmoid pattern with pH increase and was above 70% at pH 10.5. Based on these differentiated optimal pH regimes for the growth and flocculation, an integrated process consisting of cultivation and settling vessels was proposed. The integrated process demonstrated that high flocculation activity of Ettlia sp. YC001 could be achieved in the settling vessel with various hydraulic retention times by only irradiation of light to maintain high pH while maintaining the optimal growth in cultivation vessel with the light irradiation and CO2 supply at pH 8.5. Thus, the proposed strategy for pH control would provide a simple, cost-effective, and flexible design and operation for microalgae cultivation-harvest systems.


Asunto(s)
Reactores Biológicos/microbiología , Dióxido de Carbono/metabolismo , Microalgas , Volvocida , Biomasa , Floculación , Concentración de Iones de Hidrógeno , Luz , Metabolismo de los Lípidos , Microalgas/metabolismo , Microalgas/fisiología , Microalgas/efectos de la radiación , Fotosíntesis , Volvocida/metabolismo , Volvocida/fisiología , Volvocida/efectos de la radiación
10.
J Nanosci Nanotechnol ; 15(8): 5617-23, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26369127

RESUMEN

Given the emergence of nanotherapeutics and nanodiagnostics as key tools in today's medicine, it has become of critical importance to define the interactions of nanomaterials with biological systems. The biomedical applications of nanoparticles (NPs) in chemical sensing, biological imaging, drug delivery, photothermal therapy and cancer treatment have been demonstrated. Gold NPs as new biomedical tools are the focus of research due to their ease of synthesis, chemical stability and unique optical properties. Therefore, there is a need to establish the toxicity, side effects and safety of gold NPs for human applications. To study the in vitro cytotoxicity of gold NPs, we performed MTT assay using two types of gold NPs such as gold nanorods (GNRs) and gold nanowires (GNWs). The percentage cytotoxicity of damaged neural precursor cells (NPCs) that were treated with 100 mg GNRs was 97.5±3.9%; and proportion of damaged NPCs following the administration of the same dose of GNWs was 98.8±0.3%. The cytotoxicity of 10 mg GNRs in NPCs was 54.4±8.3%, whereas it was 98.7±0.6% for the same dose of GNWs. Then, to verify that gold NPs induced apoptotic cell death in NPCs, the LIVE/DEAD Viability/Cytotoxicity assay was performed. We observed that cell death of NPCs increased with an increase in quantity of both types of gold NPs. Cell viability assessed the overall dose-dependent toxicity of NPs in cultured cells. As the results suggest, this study demonstrated that treatment with gold NPs resulted in cellular toxicity in a dose-dependent manner in cultured NPCs.


Asunto(s)
Oro/toxicidad , Nanotubos/toxicidad , Nanocables/toxicidad , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/fisiología , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Dosificación Letal Mediana , Ensayo de Materiales , Células-Madre Neurales/citología , Tamaño de la Partícula
11.
J Phys Ther Sci ; 27(12): 3641-3, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26834322

RESUMEN

[Purpose] This study compared the knowledge of and attitudes toward dementia between health-related and non-health-related students. [Subjects] The subjects consisted of a total of 416 people, 213 health-related students and 203 non-health-related students, at K University, which is located in Gyeongsangbuk-do, Republic of Korea, between May 1 and 14, 2014. [Methods] The subjects answered a self-administered questionnaire about their knowledge of and attitudes toward dementia. [Results] There was a significant difference in knowledge of and attitudes toward dementia between the two groups examined. [Conclusion] Health-related students displayed higher knowledge of dementia and a more positive attitude toward dementia compared with non-health-related students. In the future, education to cultivate professional knowledge about dementia and enhance positive attitudes toward dementia should be provided continuously to health-related students. This is because students in health-related fields will likely provide services to patients with dementia in the clinical field. Additionally, as they will likely provide support to the elderly in the future, non-health-related students also need to be educated about and develop positive attitudes toward dementia.

12.
Plant Physiol ; 162(2): 1030-41, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23656895

RESUMEN

Arabidopsis (Arabidopsis thaliana) CYCLIN-DEPENDENT KINASE Ds (CDKDs) phosphorylate the C-terminal domain of the largest subunit of RNA polymerase II. Arabidopsis CYCLIN H;1 (CYCH;1) interacts with and activates CDKDs; however, the physiological function of CYCH;1 has not been determined. Here, we report that CYCH;1, which is localized to the nucleus, positively regulates blue light-induced stomatal opening. Reduced-function cych;1 RNA interference (cych;1 RNAi) plants exhibited a drought tolerance phenotype. CYCH;1 is predominantly expressed in guard cells, and its expression was substantially down-regulated by dehydration. Transpiration of intact leaves was reduced in cych;1 RNAi plants compared with the wild-type control in light but not in darkness. CYCH;1 down-regulation impaired blue light-induced stomatal opening but did not affect guard cell development or abscisic acid-mediated stomatal closure. Microarray and real-time polymerase chain reaction analyses indicated that CYCH;1 did not regulate the expression of abscisic acid-responsive genes or light-induced stomatal opening signaling determinants, such as MYB60, MYB61, Hypersensitive to red and blue1, and Protein phosphatase7. CYCH;1 down-regulation induced the expression of redox homeostasis genes, such as LIPOXYGENASE3 (LOX3), LOX4, ARABIDOPSIS GLUTATHIONE PEROXIDASE 7 (ATGPX7), EARLY LIGHT-INDUCIBLE PROTEIN1 (ELIP1), and ELIP2, and increased hydrogen peroxide production in guard cells. Furthermore, loss-of-function mutations in CDKD;2 or CDKD;3 did not affect responsiveness to drought stress, suggesting that CYCH;1 regulates the drought stress response in a CDKD-independent manner. We propose that CYCH;1 regulates blue light-mediated stomatal opening by controlling reactive oxygen species homeostasis.


Asunto(s)
Arabidopsis/fisiología , Ciclina H/metabolismo , Estomas de Plantas/fisiología , Especies Reactivas de Oxígeno/metabolismo , Estrés Fisiológico , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ciclina H/genética , Quinasas Ciclina-Dependientes/genética , Quinasas Ciclina-Dependientes/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Luz , Mutación , Transpiración de Plantas , Plantas Modificadas Genéticamente , Interferencia de ARN
13.
J Craniofac Surg ; 25(5): 1846-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25203581

RESUMEN

Jaw fracture surgery or orthognathic surgery usually involves the application of an intermaxillary fixation (IMF). Obstructions that cannot be relieved by suction require an immediate release of IMF wires, but releasing the IMF may damage the surgical alignment of the facial bones. The mean time taken to release the jaws was an average of 2 minutes 9 seconds by hospital staff involved in caring for these patients. The aims of this study were to introduce a training model for wire-guided percutaneous cricothyrotomy in the patients applying an IMF and to perform the procedure for medical students. Our model consisted of a facial mannequin, a plastic breathing tube, 2 rolls of tapes, and a reservoir bag. The inner parts of the 2 used rolls of tape represent tracheal/cricoid rings (1-inch width for thyroid and half-inch width for cricoid), and the space between them represents the cricothyroid membrane, which is wrapped with Peha-Haft. A surgeon demonstrated the technique on the model, and then, 60 medical students who had never attended airway-training courses applied the Melker cricothyrotomy kit on the model. All 60 students completed the procedure successfully. The mean (SD) time needed to insert a cricothyrotomy catheter of the medical students was 175 (50) seconds (range, 76-297 s). Most of the students (54; 90%) performed it within 4 minutes; more than half (33; 55%), within 3 minutes. With our manikin model and Melker cricothyrotomy kit, 60 medical students completed the procedure successfully. This model can be useful to cricothyrotomy training for medical personnel.


Asunto(s)
Cartílago Cricoides/cirugía , Técnicas de Fijación de Maxilares , Maniquíes , Materiales de Enseñanza , Cartílago Tiroides/cirugía , Traqueostomía/métodos , Adulto , Obstrucción de las Vías Aéreas/cirugía , Cateterismo/instrumentación , Dilatación/instrumentación , Femenino , Humanos , Intubación Intratraqueal/instrumentación , Masculino , Agujas , Tempo Operativo , Respiración Artificial/métodos , Estudiantes de Medicina , Factores de Tiempo , Traqueostomía/instrumentación , Traqueotomía/instrumentación , Traqueotomía/métodos , Adulto Joven
14.
Sci Total Environ ; 948: 174833, 2024 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-39025143

RESUMEN

Deep-sea mining can remobilize large amounts of inert metals from hydrothermal seafloor massive sulfides (SMSs) into bioavailable toxic forms that are dissolved in the water column, potentially impacting marine ecosystems. It is thus critical to assess the impacts of deep-sea mining on the reactivities and behaviors of crucial elements (e.g., Zn and Cu) and their isotopes during mineral leaching processes. To this end, we conducted leaching experiments using different SMS mineral types (CuFe rich, Fe rich, and ZnFe rich) to assess metal releases and the isotope fractionations of Zn and Cu. Significant correlations were observed between Ni, Cu, Zn, Cd, and Pb concentrations in leachates and the SMSs, suggesting that metal leaching into seawater depended on individual SMS metal content. The Zn and Cu concentrations in leachates varied greatly by both SMS type and the leaching time. Zn concentrations from ZnFe rich SMSs exceeded the recommended effluent limits set by the IFC World Bank and the USEPA. SMS ore leachates exhibited Cu and Zn isotope ratios distinct from those of Indian Ocean deep seawater. The isotope fractionation magnitude (Δore-seawater) of Cu was more pronounced than that of Zn, likely due to the redox process involved in the leaching processes. In contrast, the Zn isotope signatures in leachates conserve those of minerals, although slight isotope fractionations occurred in solution following the adsorption and precipitation processes of Fe-oxyhydroxides. Our findings confirm that leveraging the chemical and isotope signatures of toxic metals offers a valuable approach for assessing the extent of metal contamination of leachates and mine tailings stemming from deep-sea mining operations, concerning their influence on the surrounding water columns.

15.
Plant Direct ; 8(5): e594, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38799417

RESUMEN

The transcription factor GT2-LIKE 1 (GTL1) has been implicated in orchestrating a transcriptional network of diverse physiological, biochemical, and developmental processes. In response to water-limiting conditions, GTL1 is a negative regulator of stomatal development, but its potential rolein other water-deficit responses is unknown. We hypothesized that GTL1 regulates transcriptome changes associated with drought tolerance over leaf developmental stages. To test the hypothesis, gene expression was profiled by RNA-seq analysis in emerging and expanding leaves of wild-type and a drought-tolerant gtl1-4 knockout mutant under well-watered and water-deficit conditions. Our comparative analysis of genotype-treatment combinations within leaf developmental age identified 459 and 1073 differentially expressed genes in emerging and expanding leaves, respectively, as water-deficit responsive GTL1-regulated genes. Transcriptional profiling identified a potential role of GTL1 in two important pathways previously linked to drought tolerance: flavonoid and polyamine biosynthesis. In expanding leaves, negative regulation of GTL1 under water-deficit conditions promotes biosynthesis of flavonoids and anthocyanins that may contribute to drought tolerance. Quantification of polyamines did not support a role for GTL1 in these drought-responsive pathways, but this is likely due to the complex nature of polyamine synthesis and turnover. Our global transcriptome analysis suggests that transcriptional repression of GTL1 by water deficit allows plants to activate diverse pathways that collectively contribute to drought tolerance.

16.
ACS Nano ; 18(8): 6373-6386, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38349619

RESUMEN

Ionic memristor devices are crucial for efficient artificial neural network computations in neuromorphic hardware. They excel in multi-bit implementation but face challenges like device reliability and sneak currents in crossbar array architecture (CAA). Interface-type ionic memristors offer low variation, self-rectification, and no forming process, making them suitable for CAA. However, they suffer from slow weight updates and poor retention and endurance. To address these issues, the study demonstrated an alkali ion self-rectifying memristor with an alkali metal reservoir formed by a bottom electrode design. By adopting Li metal as the adhesion layer of the bottom electrode, an alkali ion reservoir was formed at the bottom of the memristor layer by diffusion occurring during the atomic layer deposition process for the Na:TiO2 memristor layer. In addition, Al dopant was used to improve the retention characteristics by suppressing the diffusion of alkali cations. In the memristor device with optimized Al doping, retention characteristics of more than 20 h at 125 °C, endurance characteristics of more than 5.5 × 105, and high linearity/symmetry of weight update characteristics were achieved. In reliability tests on 100 randomly selected devices from a 32 × 32 CAA device, device-to-device and cycle-to-cycle variations showed low variation values within 81% and 8%, respectively.

17.
Bioresour Technol ; 412: 131408, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39222861

RESUMEN

Production of functional biocompounds from microalgae has garnered interest from different industrial sectors; however, their overall productivity must be substantially improved for commercialization. Herein, long-term acclimation of Scenedesmus deserticola was conducted using glucose as an organic carbon source to enhance its heterotrophic capabilities and the production potential of loliolide. A year-long acclimation on agar plates led to the selection of S. deserticola HS4, which exhibited at least 2-fold increase in loliolide production potential; S. deserticola HS4 was subjected to further screening of its cultivation conditions and fed-batch cultivation was subsequently performed in liter-scale reactors. While S. deserticola HS4 exhibited shifts in cellular morphology and biochemical composition, the results suggested a substantial increase in its loliolide productivity regardless of trophic modes. Collectively, these results highlight the potential of long-term acclimation as an effective strategy for improving microalgal crops to align with industrial production practices.


Asunto(s)
Aclimatación , Carbono , Scenedesmus , Scenedesmus/metabolismo , Carbono/farmacología , Glucosa/metabolismo , Reactores Biológicos , Microalgas/metabolismo , Compuestos Orgánicos , Biomasa
18.
Plant Cell ; 22(12): 4128-41, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21169508

RESUMEN

A goal of modern agriculture is to improve plant drought tolerance and production per amount of water used, referred to as water use efficiency (WUE). Although stomatal density has been linked to WUE, the causal molecular mechanisms have yet to be determined. Arabidopsis thaliana GT-2 LIKE 1 (GTL1) loss-of-function mutations result in increased water deficit tolerance and higher integrated WUE by reducing daytime transpiration without a demonstrable reduction in biomass accumulation. gtl1 plants had higher instantaneous WUE that was attributable to ~25% lower transpiration and stomatal conductance but equivalent CO(2) assimilation. Lower transpiration was associated with higher STOMATAL DENSITY AND DISTRIBUTION1 (SDD1) expression and an ~25% reduction in abaxial stomatal density. GTL1 expression occurred in abaxial epidermal cells where the protein was localized to the nucleus, and its expression was downregulated by water stress. Chromatin immunoprecipitation analysis indicated that GTL1 interacts with a region of the SDD1 promoter that contains a GT3 box. An electrophoretic mobility shift assay was used to determine that the GT3 box is necessary for the interaction between GTL1 and the SDD1 promoter. These results establish that GTL1 negatively regulates WUE by modulating stomatal density via transrepression of SDD1.


Asunto(s)
Adaptación Fisiológica/fisiología , Proteínas de Arabidopsis/fisiología , Regulación hacia Abajo/fisiología , Sequías , Estomas de Plantas/metabolismo , Serina Endopeptidasas/genética , Agua/metabolismo , Proteínas de Arabidopsis/genética , Ensayo de Cambio de Movilidad Electroforética , Regulación de la Expresión Génica de las Plantas/fisiología , Microscopía Fluorescente , Mutación , Regiones Promotoras Genéticas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
Anesth Analg ; 116(1): 178-84, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23223102

RESUMEN

BACKGROUND: In this study we evaluated the effect of passive leg elevation (LE) and Trendelenburg (T) position on the cross-sectional area (CSA) of the internal jugular vein (IJV) in infants and young children undergoing surgery for congenital heart disease. A secondary aim was to compare the CSA of the IJV between subjects with right-to-left (RL) shunt and left-to-right (LR) shunt. METHODS: Ninety infants and small children from 10 days to 31 months old weighing from 1.5 to 9.7 kg were assigned to group RL (n = 48) or LR (n = 42). In both groups, the CSA, transverse, and vertical diameters of the IJV on both sides of the neck were measured using a 2-dimensional ultrasound transducer in the following positions: supine position, 15° of T position, supine position with 50° of LE, and 15° of Trendelenburg position with 50° of LE (TLE). A more than 25% increase in mean CSA of the IJV was considered clinically significant. RESULTS: In group LR, T, LE, and TLE significantly increased CSA of both right (at least 12.3%, 10.3%, and 18.3%, respectively, "at least" refers to the lower 95% confidence limits) and left (at least 15.8%, 15.0%, and 18.9%, respectively) IJVs, whereas only TLE increased the CSA of both IJVs significantly in group RL (at least 8.2% and 7.7% in the right and left, respectively). The increase in the CSA of the right IJV related to T and TLE was larger in group LR than in group RL (at least 12.3% vs 1.2% for T and at least 18.3% vs 8.2% for TLE, respectively). A clinically significant increase in CSA was achieved in both right and left IJVs with TLE in group LR (mean 28.6% and 26.3%, respectively). The CSA of the right IJV was larger than that of the left IJV in most (at least 69.2%) patients. CONCLUSIONS: Passive LE was as effective as T position to increase the CSA of the IJV, but there was no clinically significant increase in the CSA with any single maneuver. Only T position with passive LE achieved a clinically significant increase in the CSA of both IJVs in infants and young children with LR shunt, but not in the same age group with RL shunt.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Inclinación de Cabeza/fisiología , Cardiopatías Congénitas/cirugía , Venas Yugulares/anatomía & histología , Pierna/fisiología , Anatomía Transversal , Anestesia General , Femenino , Humanos , Lactante , Recién Nacido , Venas Yugulares/diagnóstico por imagen , Masculino , Tamaño de la Muestra , Posición Supina , Ultrasonografía
20.
J Nanosci Nanotechnol ; 13(9): 6463-6, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24205684

RESUMEN

The electrical bistabilities and the memory stabilities of organic bistable devices (OBDs) based on multi-core-shell CdSe/CdS/ZnS nanoparticles embedded in a polystyrene (PS) layer fabricated by using a spin-coating method were investigated. The current density-voltage (J-V) curves for the Al/multi-core-shell CdSe/CdS/ZnS nanoparticles embedded in PS layer/WO3/indium-tin-oxide (ITO) devices showed current bistability with a maximum ON/OFF ratio of 1 x 10(3), which was much larger than that of a device without a WO3 layer. The leakage current of the OBDs was decreased by insertion of the WO3 layer between the PS layer containing nanoparticles and the ITO electrode, resulting in a decrease in the current deviation between the experimental and the simulated currents in the low-voltage region. The effects of the WO3 blocking layer on the electrical characteristics of the OBDs were investigated, and the carrier transport mechanisms for the OBDs were described on the basis of the J-V experimental data and theoretical results.

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