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1.
Nature ; 627(8004): 505-509, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38418881

RESUMEN

The Double Asteroid Redirection Test (DART) had an impact with Dimorphos (a satellite of the asteroid Didymos) on 26 September 20221. Ground-based observations showed that the Didymos system brightened by a factor of 8.3 after the impact because of ejecta, returning to the pre-impact brightness 23.7 days afterwards2. Hubble Space Telescope observations made from 15 minutes after impact to 18.5 days after, with a spatial resolution of 2.1 kilometres per pixel, showed a complex evolution of the ejecta3, consistent with other asteroid impact events. The momentum enhancement factor, determined using the measured binary period change4, ranges between 2.2 and 4.9, depending on the assumptions about the mass and density of Dimorphos5. Here we report observations from the LUKE and LEIA instruments on the LICIACube cube satellite, which was deployed 15 days in advance of the impact of DART. Data were taken from 71 seconds before the impact until 320 seconds afterwards. The ejecta plume was a cone with an aperture angle of 140 ± 4 degrees. The inner region of the plume was blue, becoming redder with increasing distance from Dimorphos. The ejecta plume exhibited a complex and inhomogeneous structure, characterized by filaments, dust grains and single or clustered boulders. The ejecta velocities ranged from a few tens of metres per second to about 500 metres per second.

2.
Eur Rev Med Pharmacol Sci ; 27(22): 11115-11121, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38039043

RESUMEN

OBJECTIVE: This study aimed to compare the efficacy and safety of flexible ureteroscopic lithotripsy (FURSL) and mini-percutaneous nephrolithotomy (mPCNL) in the treatment of 2-3 cm renal calculi in women. PATIENTS AND METHODS: Clinical data of 186 patients who underwent mPCNL (n=96) and FURSL (n=90) surgery in our hospital from June 2018 to February 2023 were collected. Several parameters were assessed and compared between the two groups, including operation duration, length of hospital stay, cost of hospitalization, pain intensity measured by the visual analogue scale (VAS), patient comfort assessed using the Bruggrmann Comfort Scale (BCS), decrease in hemoglobin levels, changes in blood urea nitrogen (BUN), fluctuations in serum creatinine (Scr), hypersensitive C-reactive protein (hs-CRP) levels, complication rates, immediate post-operative stone-free rate (RSFR), and long-term stone-free rate (LSFR). RESULTS: The comparative analysis of patient age, body mass index (BMI), stone size, computed X-ray tomography (CT) value of stones, number of stones, and comorbidities revealed no statistically significant differences between the mPCNL and FURSL groups (p>0.05). The mPCNL cohort exhibited a markedly lower duration of operation (p<0.001) and BCS score (p<0.001) compared to the FURSL cohort. Nonetheless, the mPCNL cohort demonstrated significantly higher hospitalization expenses (p<0.001), length of hospital stay (p<0.001), VAS score for pain (p<0.001), and level of hemoglobin decrease (p<0.001) in comparison to the FURSL cohort. Moreover, the immediate post-operative stone-free rate (RSFR) was significantly higher in the mPCNL group (p=0.007). The long-term stone-free rate (LSFR), however, showed no significant difference between the two groups (p=0.160). Furthermore, the FURSL group exhibited significantly fewer overall complications in contrast to the mPCNL group (p=0.006). CONCLUSIONS: mPCNL and FURSL are both safe and effective surgical methods for treating 2-3 cm renal calculi in women. However, FURSL holds distinct advantages, including minimally invasive procedure, accelerated recovery, reduced cost, and lower incidence of complications.


Asunto(s)
Cálculos Renales , Litotricia , Nefrolitotomía Percutánea , Humanos , Femenino , Nefrolitotomía Percutánea/efectos adversos , Nefrolitotomía Percutánea/métodos , Ureteroscopía/efectos adversos , Ureteroscopía/métodos , Cálculos Renales/cirugía , Litotricia/métodos , Hemoglobinas , Resultado del Tratamiento
3.
Eur Rev Med Pharmacol Sci ; 27(20): 9721-9728, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37916335

RESUMEN

OBJECTIVE: This study aimed to investigate the relationship between common clinical immune indicators, disability degree, and cognitive impairment in patients with neuromyelitis optica spectrum disorder (NMOSD). PATIENTS AND METHODS: We retrospectively analyzed lymphocyte subsets and routine parameters in the peripheral blood of 55 patients with NMOSD. We assessed the degree of disability using the Extended Disability Status Scale (EDSS). The Montreal Cognitive Assessment (MoCA) scores were used to assess cognitive function. In addition, we also determined the cytokine levels in 33 patients with NMOSD. The relationships of these immunological indicators with disability and cognitive impairment were assessed using correlation and multiple linear regression analyses. RESULTS: The results of the multiple linear regression analysis suggested that for patients with NMOSD, the neutrophil-lymphocyte ratio (NLR) (ß=0.072, p=0.034) and number of attacks (ß=0.131, p=0.03) were positively correlated with EDSS scores, whereas the number of attacks was positively correlated with MoCA scores. In addition, we also collected cytokine levels in 33 of these patients. The results of the study showed a positive correlation between IL-10 and EDSS scores and a negative correlation between IL-6 and MoCA scores. CONCLUSIONS: Our results show that these immune cells and cytokines are, to some extent, associated with the degree of disability and cognitive impairment in patients with NMOSD. Closely monitoring these indicators may allow detecting changes in patients' disease courses and predicting the severity of their disease. In clinical practice, this may facilitate early intervention and appropriate treatment decisions, which may improve the management of patient prognosis.


Asunto(s)
Disfunción Cognitiva , Neuromielitis Óptica , Humanos , Neuromielitis Óptica/complicaciones , Estudios Retrospectivos , Pronóstico , Citocinas , Disfunción Cognitiva/complicaciones , Acuaporina 4
4.
Eur Rev Med Pharmacol Sci ; 27(13): 6071-6080, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37458656

RESUMEN

OBJECTIVE: The novel short-acting benzodiazepine remimazolam besylate acts rapidly and is used to induce easily controlled sedation. The aim of this study was to investigate the effects of remimazolam besylate combined with alfentanil in patients undergoing fiberoptic bronchoscopy with preserved spontaneous breathing. PATIENTS AND METHODS: 192 patients undergoing painless fiberoptic bronchoscopy were randomly assigned to either propofol (P group) or remimazolam besylate (R group); both groups also received alfentanil 10 µg/kg. The respiratory rate was recorded during the inspection. Mean arterial pressure (MAP), heart rate (HR), oxygen saturation (SpO2), Narcotrend values and Modified Observer's Assessment of Alertness and Sedation (MOAA/S) scores were recorded after entry to the operating room (T0), 1 min (T1), 2 min (T2) and 3 min (T3) after anesthesia, immediately after the bronchoscope entered the vocal cords (T4), when the bronchoscope reached the carina (T5), the patient's eyes opened (T6), and 30 min postoperatively (T7). Secondary outcomes included intraoperative hypotension and body movement grading, etc. RESULTS: There was less respiratory depression during the inspection in the R group than in the P group (p < 0.01). The rate of hypotension during the examination was higher in the P group than in the R group (p < 0.01). Narcotrend values in the P group were less for the R group at the T1-T5 time points (p < 0.01). No difference in the number of body movements ≥ grade 3 was found between the two groups (p > 0.05). CONCLUSIONS: Remimazolam besylate combined with alfentanil for painless fiberoptic bronchoscopy can better preserve the patient's spontaneous breathing and reduce the incidence of respiratory depression during the inspection than propofol.


Asunto(s)
Hipotensión , Propofol , Insuficiencia Respiratoria , Humanos , Propofol/uso terapéutico , Alfentanilo , Broncoscopía , Estudios Prospectivos , Benzodiazepinas , Hipnóticos y Sedantes
5.
Eur J Paediatr Dent ; 23(1): 21-26, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35274538

RESUMEN

AIM: The aim of the present study was to explore the epidemiological characteristics and treatment of traumatic dental injuries of primary dentition (TDI-p) in Xi'an, China. MATERIALS: Data of children with TDI-p admitted between January 2018 and December 2019 at the Department of Pediatric Dentistry, Xi'an Jiaotong University Stomatology Hospital were retrospectively analysed. The epidemiological distribution characteristics and related treatment information of TDI-p were described. CONCLUSION: Compared with permanent dentition, TDI-p has its particularities, such as type of trauma, treatment procedure, and behavioural management. More attention should be paid to TDI-p by both dentists and guardians.


Asunto(s)
Traumatismos de los Dientes , Niño , China/epidemiología , Dentición Permanente , Humanos , Estudios Retrospectivos , Traumatismos de los Dientes/epidemiología , Traumatismos de los Dientes/terapia , Diente Primario
6.
Space Sci Rev ; 218(2): 5, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35250103

RESUMEN

Two of the instruments onboard the OSIRIS-REx spacecraft, the MapCam color imager and the OVIRS visible and infrared spectrometer, observed the surface of asteroid (101955) Bennu in partially overlapping wavelengths. Significant scientific advances have been enabled by using data from these two instruments in tandem, but a robust statistical understanding of their relationship is needed for future analyses to cross-compare their data as accurately and sensitively as possible. Here we present a cross-instrument comparison of data acquired by MapCam and OVIRS, including methods and results for all global and site-specific observation campaigns in which both instruments were active. In our analysis, we consider both the absolute radiometric offset and the relative (normalized) variation between the two instruments; we find that both depend strongly on the photometric and instrumental conditions during the observation. The two instruments have a large absolute offset (>15%) due to their independent radiometric calibrations. However, they are very consistent (relative offset as low as 1%) when each instrument's response is normalized at a single wavelength, particularly at low phase angles where shadows on Bennu's rough surface are minimized. We recommend using the global datasets acquired at 12:30 pm local solar time for cross-comparisons; data acquired at higher phase angles have larger uncertainties.

7.
Eur Rev Med Pharmacol Sci ; 26(2): 623-636, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35113438

RESUMEN

OBJECTIVE: Parkinson's disease (PD) is one of the neurodegenerative diseases. Galectin-1 (Gal-1) is expressed in the central nervous system. Our study sought to explore the neuroprotective effect of Gal-1 in 1­methyl­4­phenyl pyridine ion (MPP+)-induced cytotoxicity on SH-SY5Y cells. MATERIALS AND METHODS: SH-SY5Y cells were cultured in vitro, pretreated with Gal-1, and then exposed to MPP+. Thereafter, the generation of reactive oxygen species (ROS) in SH-SY5Y cells was investigated. The effects of Gal-1 on DNA breakage, cell damage (release of lactate dehydrogenase (LDH)), viability, and apoptosis in SH-SY5Y cells were examined by comet assay, LDH assay, WST-1 assay, and flow cytometry, respectively. Additionally, the regulatory effect of Gal-1 on Nrf2 expression was examined by western blot. Zebrafish embryos were pretreated with Gal-1 and then exposed to MPP+. The locomotor ability of zebrafish larvae was then investigated. RESULTS: MPP+ induced the production of ROS in cells, which can be alleviated by pretreatment with Gal-1. Gal-1 protected cells from MPP+-induced cytotoxicity by preventing DNA breakage and cell injury. Gal-1 inhibited apoptosis in SH-SY5Y cells. The neuroprotective effect of Gal-1 could be abolished when Nrf2 expression knockdown. Moreover, exposure to MPP+ decreased the locomotor activity of zebrafish, which was attenuated by pretreatment with Gal-1. CONCLUSIONS: Our study demonstrated that the administration of Gal-1 could protect neurons from cellular stress by preventing apoptosis and eliminating ROS. Moreover, the neuroprotective effect of Gal-1 in neuronal cells could be related to the activation of Nrf2 expression. Therefore, Gal-1 could be a promising strategy for treating PD.


Asunto(s)
Fármacos Neuroprotectores , Enfermedad de Parkinson , 1-Metil-4-fenilpiridinio/toxicidad , Animales , Apoptosis , Línea Celular Tumoral , Supervivencia Celular , Galectina 1/genética , Galectina 1/metabolismo , Galectina 1/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/genética , Especies Reactivas de Oxígeno/metabolismo , Pez Cebra/metabolismo
8.
Eur Rev Med Pharmacol Sci ; 25(20): 6260-6270, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34730205

RESUMEN

OBJECTIVE: Elderly patients with hip fractures are frequently under anticoagulant therapy. We aimed to assess if outcomes of hip fracture patients undergoing surgical intervention differ with prior use of direct oral anticoagulants (DOAC) or Vitamin K antagonists (VKA). MATERIALS AND METHODS: PubMed, Embase, and Google Scholar were searched for comparative studies published up to June 20, 2021. Dichotomous variables were summarized using odds ratio (OR) and continuous variables using mean difference (MD). RESULTS: Fourteen studies were included. There was no difference in the time to surgery between patients on DOAC or VKA (MD: 2.50 95% CI -2.10, 7.10 I2=76% p=0.29). Number of undergoing surgeries within 48 hours was not significantly different between the two groups (OR: 0.77 95% CI 0.56, 1.06 I2=10% p=0.10). Mortality rates (OR: 0.84 95% CI 0.62, 1.14 I2=12% p=0.27), blood transfusion requirement (OR: 1.08 95% CI 0.80, 1.47 I2=30% p=0.62) and length of hospital stay (MD: 0.26 95% CI -0.70, 1.21 I2=0% p=0.60) was also not significantly different between patients on DOAC or VKA. CONCLUSIONS: There is no difference in surgical delay, early mortality, blood transfusion rates and length of hospital stay between DOAC uses and VKA users undergoing hip fracture surgery.


Asunto(s)
Anticoagulantes/administración & dosificación , Fracturas de Cadera/cirugía , Vitamina K/antagonistas & inhibidores , Anciano , Transfusión Sanguínea/estadística & datos numéricos , Fracturas de Cadera/mortalidad , Humanos , Tiempo de Internación/estadística & datos numéricos , Factores de Tiempo
9.
Z Rheumatol ; 80(5): 432-446, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33346891

RESUMEN

The current systematic review and meta-analysis aims to evaluate the efficacy and safety of iguratimod (IGU) combined with methotrexate (MTX) versus MTX alone in rheumatoid arthritis (RA). Two independent investigators searched for original randomized controlled trials (RCTs) related to the combination of IGU and MTX in RA published before November 1, 2019, in PubMed, Cochrane Library, Embase, the China National Knowledge Infrastructure (CNKI), the Chinese Biomedical Literature Database (CBM), and WanFang Data. Additionally, we searched clinical trial registry websites. We assessed the methodological quality of the included trials using the Cochrane Collaboration tool and the seven-point Jadad scale. Statistical analyses were performed using Review Manager (RevMan) 5.3 (Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). Meta-regression and publication bias analyses were performed using Stata version 14 software (StataCorp., College Station, TX, USA). A total of 7 RCTs consisting of 665 participants, with 368 participants in the active arm and 297 in the placebo arm, were included in the meta-analysis. The American College of Rheumatology (ACR) value was better in the IGU + MTX group than in the MTX alone group, with a pooled relative risk (RR) for ACR20 (American College of Rheumatology 20% improvement criteria), ACR50, and ACR70 of 1.40 (95% CI, 1.13-1.74), 2.09 (95% CI, 1.67-2.61), and 2.24 (95% CI, 1.53-3.28), respectively. The results of the meta-analysis demonstrated that there was no statistical significance in adverse events (1.06 (95% CI, 0.92-1.23)). The combined treatment is an effective, safe, and economical treatment option for patients who do not respond well to methotrexate alone or for patients who cannot afford expensive biologics that have no confirmed efficacy.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Antirreumáticos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , China , Cromonas , Quimioterapia Combinada , Humanos , Metotrexato/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Sulfonamidas , Resultado del Tratamiento
10.
Eur Rev Med Pharmacol Sci ; 24(23): 12041-12049, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33336722

RESUMEN

OBJECTIVE: We investigated the effect of electrical stimulation (ES) of varying pulse frequency on differentiation and proliferation of canine myloglossus satellite cells in vitro. MATERIALS AND METHODS: Cellular viability and proliferation were assayed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay and flow cytometry fluorescence-activated cell sorting analysis. Cellular differentiation and expression of mark molecule were assayed by Real Time-PCR and Western blot. RESULTS: With increasing frequency ES, we found a significant increase in Myod (r=0.988, p<0.0001), myogenin (r=0.988, p<0.0001), MyHC-slow (r=0.988, p<0.0001), MyHC-fast (r=0.875, p<0.0001) protein expression, and Pax7 mRNA expression (r=0.712, p=0.001). CONCLUSIONS: Pax7 mRNA expression and MyoD, myogenin, and MyHC protein expression were increased with increment of electrical stimulation frequency in myloglossus muscle satellite. Higher frequency ES enhanced myloglossus satellite cell differentiation, not proliferation and viability.


Asunto(s)
Estimulación Eléctrica , Células Satélite del Músculo Esquelético/metabolismo , Regulación hacia Arriba , Animales , Diferenciación Celular , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Perros , Femenino , Proteína MioD/genética , Proteína MioD/metabolismo , Miogenina/genética , Miogenina/metabolismo , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo , Factor de Transcripción PAX7/genética , Factor de Transcripción PAX7/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Células Satélite del Músculo Esquelético/citología
11.
Eur Rev Med Pharmacol Sci ; 24(21): 11386-11394, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33215460

RESUMEN

OBJECTIVE: To explore the expression and significance of SAA, CRP and FERR in patients diagnosed with COVID-19. PATIENTS AND METHODS: A total of 225 patients diagnosed with COVID-19 who were admitted to the North Hospital of First Hospital in Changsha, China, from 9th February 2020 to 7th March 2020 were enrolled. Their general data, laboratory test results and levels of SAA, CRP and FERR were extracted from electronic medical records. RESULTS: Age was an important risk factor for the severity of COVID-19 in the patients. Compared with the non-severe group, the severe group showed statistical significance in the levels of total protein, albumin, ALT and AST in liver function, UA in renal function, myocardial enzyme CK-MB and LDH, and immunoglobulin IgG and IgM. The levels of SAA, CRP, and FERR were significantly increased in patients with severe COVID-19. ROC curve analysis results showed that the AUC, from small to large, was as follows: SAA+CRP+FERR, CRP + FERR, SAA + CRP, SAA + FERR, SAA, FERR, and CRP, which indicated the benefit of the combination of the three indicators. The sensitivity and specificity of the combined detection of the three indicators were higher than those of the detection of any single indicator or two combined indicators. A Spearman correlation analysis of the data showed that the initial CRP/SAA, SAA/FERR, and CRP/FERR were positively correlated. The continuous results of SAA, CRP and FERR throughout the study period showed that the values of the severe group on a given day were higher than those of the non-severe group; the values of the two groups peaked on the 5th or 7th day and then decreased, and the decreasing trend of the severe group was more evident. CONCLUSIONS: SAA, CRP and FERR are sensitive serological indicators used to evaluate the severity of COVID-19. The combined detection of serum SAA, FERR, and CRP, which are positively related to COVID-19 infection, offers guiding significance for the occurrence of COVID-19 infection and the severity of the disease. Such detection provides effective detection indicators for the progress and prognosis of COVID-19; these indicators will enable effective intervention measures to be implemented in time and the rates of severe illness and mortality to be reduced.


Asunto(s)
Proteína C-Reactiva/análisis , Infecciones por Coronavirus/diagnóstico , Ferritinas/sangre , Neumonía Viral/diagnóstico , Proteína Amiloide A Sérica/análisis , Adulto , Factores de Edad , Anciano , Betacoronavirus/aislamiento & purificación , Betacoronavirus/patogenicidad , Biomarcadores/sangre , COVID-19 , China/epidemiología , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/mortalidad , Infecciones por Coronavirus/virología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/sangre , Neumonía Viral/mortalidad , Neumonía Viral/virología , Pronóstico , Estudios Retrospectivos , SARS-CoV-2 , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
12.
Science ; 370(6517)2020 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-33033155

RESUMEN

The composition of asteroids and their connection to meteorites provide insight into geologic processes that occurred in the early Solar System. We present spectra of the Nightingale crater region on near-Earth asteroid Bennu with a distinct infrared absorption around 3.4 micrometers. Corresponding images of boulders show centimeters-thick, roughly meter-long bright veins. We interpret the veins as being composed of carbonates, similar to those found in aqueously altered carbonaceous chondrite meteorites. If the veins on Bennu are carbonates, fluid flow and hydrothermal deposition on Bennu's parent body would have occurred on kilometer scales for thousands to millions of years. This suggests large-scale, open-system hydrothermal alteration of carbonaceous asteroids in the early Solar System.

13.
Eur Rev Med Pharmacol Sci ; 24(10): 5367-5377, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32495871

RESUMEN

OBJECTIVE: Visfatin is significantly upregulated in colorectal cancer (CRC). However, its exact role in CRC progression and the regulatory mechanism involved in this process have not been fully illuminated. The aim of this study was to investigate the roles of visfatin in CRC progression and the potential molecular mechanism. MATERIALS AND METHODS: In vitro, two CRC cell lines (DLD-1 and SW480) were transfected with visfatin, si-visfatin, and their control vectors. Some cells were transfected with miR-140-3p mimics or miRNA negative control. Cell Counting Kit-8 and transwell invasive assays were used to detect cell proliferation and invasion ability. Luciferase reporter assays were performed to confirm whether CXC motif chemokine receptor 4 (CXCR4) directly targets miR-140-3p. Western blotting and qRT-PCR analyses were respectively conducted to evaluate the protein and mRNA levels of stromal cell-derived factor-1 (SDF-1) and CXCR4. In vivo, DLD-1 cells transfected with visfatin construct or vector control were inoculated into nude mice. After 5 weeks, the mice were sacrificed, and the tumor nodules were weighed. The expression of visfatin, SDF-1, and CXCR4 in tumor tissues was detected via immunohistochemistry analysis. RESULTS: In vitro, the transfection of visfatin promoted the proliferation and invasion of CRC cells, as well as upregulated the expression of SDF-1/CXCR4. MiR-140-3p directly targets the 3'untranslated region of CXCR4. MiR-140-3p expression was downregulated by treatment with visfatin, and miR-140-3p exerted similar effects to those of visfatin knockdown on the proliferation and invasion of CRC cells. In vivo, visfatin stimulated CRC tumor growth and downregulated miR-140-3p expression, whereas it upregulated SDF-1/CXCR4 expression. CONCLUSIONS: Visfatin promotes CRC progression by downregulating the SDF-1/CXCR4-mediated expression of miR-140-3p both in vitro and in vivo.


Asunto(s)
Quimiocina CXCL12/metabolismo , Neoplasias Colorrectales/metabolismo , Citocinas/metabolismo , Regulación hacia Abajo , MicroARNs/genética , Nicotinamida Fosforribosiltransferasa/metabolismo , Receptores CXCR4/metabolismo , Animales , Proliferación Celular , Neoplasias Colorrectales/patología , Humanos , Ratones , Ratones Desnudos , MicroARNs/metabolismo , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Células Tumorales Cultivadas
14.
Plant Biol (Stuttg) ; 22(5): 910-916, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32270571

RESUMEN

Flowers, the reproductive organs of angiosperms, show a high degree of diversity in morphological structure and flowering habit to ensure pollination and fertilization of the plants. Effect of flower movement on pollination and fertilization was investigated in Ipomoea purpurea (Convolvulaceae) in this study. Fluorescence microscopy was used to observe the germination of pollen grains at different temperatures. From 04:00 to 06:00 h, the stigma was taller than the filaments, so that self-pollination could not occur, and cross-pollination was carried out by insects. Pollen grains germinated rapidly after falling on the stigma; the pollen tube reached the ovule to complete fertilization after 2-3 h. From 07:00 to 09:00 h, filaments of two stamens grew rapidly and reached the same height as the stigma, thus allowing self-crossing. But at this time, the ambient temperature was already high and was not conducive to the germination of pollen grains. The corolla closed, forming an inverted bell shape, where the inner microenvironment ensured completion of pollen germination and fertilization. Preferential cross-pollination and delayed self-crossing of I. purpurea provided a doubly guaranteed mechanism for pollination and fertilization, facilitating its adaptation to a high temperature climate.


Asunto(s)
Fertilización , Ipomoea , Polinización , Animales , Flores , Ipomoea/fisiología , Polen
15.
Eur Rev Med Pharmacol Sci ; 24(3): 1126-1133, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32096168

RESUMEN

OBJECTIVE: To clarify the expression pattern of miRNA-875-3p in CRC and its potential regulatory effect on the progression of CRC. MATERIALS AND METHODS: MiRNA-875-3p level in 56 matched CRC tissues and adjacent normal tissues were determined. The correlation between the miRNA-875-3p level and pathological indexes of CRC patients was analyzed. Prognostic potential of miRNA-875-3p in CRC patients was assessed by introducing the Kaplan-Meier curves. Influences of miRNA-875-3p on viability, migration, and wound closure were assessed through a series of functional experiments. The interaction between miRNA-875-3p and PLK1 in regulating the progression of CRC was finally uncovered by Dual-Luciferase reporter gene and rescue experiments. RESULTS: MiRNA-875-3p was downregulated in CRC tissues and cell lines. CRC patients with low level of miRNA-875-3p suffered a higher rate of distant metastasis and worse prognosis. Overexpression of miRNA-875-3p attenuated proliferative and migratory capacities of SW480 and HT29 cells. PLK1 was confirmed to be the target gene of miRNA-875-3p. PLK1 was upregulated in CRC tissues and cell lines, which was negatively regulated by miRNA-875-3p. MiRNA-875-3p alleviated the malignant progression of CRC via negatively regulating PLK1. CONCLUSIONS: MiRNA-875-3p is downregulated in CRC, which is closely related to distant metastasis and poor prognosis of CRC patients. MiRNA-875-3p alleviates the progression of CRC through targeting and downregulating PLK1.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Neoplasias Colorrectales/metabolismo , Progresión de la Enfermedad , MicroARNs/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Anciano , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Células HT29 , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Tasa de Supervivencia/tendencias , Quinasa Tipo Polo 1
16.
Science ; 366(6470)2019 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-31806784

RESUMEN

Active asteroids are those that show evidence of ongoing mass loss. We report repeated instances of particle ejection from the surface of (101955) Bennu, demonstrating that it is an active asteroid. The ejection events were imaged by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) spacecraft. For the three largest observed events, we estimated the ejected particle velocities and sizes, event times, source regions, and energies. We also determined the trajectories and photometric properties of several gravitationally bound particles that orbited temporarily in the Bennu environment. We consider multiple hypotheses for the mechanisms that lead to particle ejection for the largest events, including rotational disruption, electrostatic lofting, ice sublimation, phyllosilicate dehydration, meteoroid impacts, thermal stress fracturing, and secondary impacts.

17.
Eur Rev Med Pharmacol Sci ; 23(15): 6394-6403, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31378877

RESUMEN

OBJECTIVE: We aimed to explore the role of microRNA-449b-5p in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and its mechanism of action. MATERIALS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay was used to detect the expression levels of microRNA-449b-5p and osteogenic markers including RUNX2, OCN during BMSCs differentiation. The microRNA-449b-5p mimic and microRNA-449b-5p inhibitors were transfected into BMSCs to achieve microRNA-449b-5p overexpression and knockdown, then the expressions of osteogenic markers were detected by qRT-PCR. The ALP activity staining and the alizarin red staining were used to detect the activity of ALP and the mineralization ability of cells after overexpression and knockdown of microRNA-449b-5p. Binding sites for microRNA-449b-5p and Satb2 were predicted by TargetScan, the PicTar and microRNAanda programs, and confirmed by dual-luciferase reporter gene assay. The relationship between microRNA-449b-5p and Satb2 was analyzed by QRT-PCR and Western blot. The microRNA-449b-5p inhibitor and shSATB2 lentivirus were simultaneously transfected in BMSCs, and the expression levels of RUNX2, OCN and ALP were detected by qRT-PCR and ALP activity assays. RESULTS: microRNA-449b-5p expression gradually decreased during osteogenic differentiation. Overexpression of microRNA-449b-5p inhibited BMSCs differentiation by down-regulating ALP activity, RUNX2, and OCN expression, while the opposite result was observed after knockdown of microRNA-449b-5p. MicroRNA-449b-5p can bind to the 3'UTR end of Satb2, which was involved in the osteogenic differentiation of microRNA-449b-5p-regulated BMSCs, and silencing of Satb2 can abolish the positive effect of the microRNA-449b-5p inhibitor on osteoblasts differentiation. CONCLUSIONS: microRNA-449b-5p could aggravate osteoporosis by inhibiting osteogenic differentiation of BMSCs through targeting Satb2.


Asunto(s)
Diferenciación Celular/fisiología , Proteínas de Unión a la Región de Fijación a la Matriz/metabolismo , Células Madre Mesenquimatosas/metabolismo , MicroARNs/metabolismo , Osteogénesis/fisiología , Osteoporosis/metabolismo , Factores de Transcripción/metabolismo , Animales , Células Cultivadas , Progresión de la Enfermedad , Unión Proteica/fisiología , Ratas
18.
Nat Astron ; 3(4): 332-340, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31360777

RESUMEN

Early spectral data from the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission reveal evidence for abundant hydrated minerals on the surface of near-Earth asteroid (101955) Bennu in the form of a near-infrared absorption near 2.7 µm and thermal infrared spectral features that are most similar to those of aqueously altered CM carbonaceous chondrites. We observe these spectral features across the surface of Bennu, and there is no evidence of substantial rotational variability at the spatial scales of tens to hundreds of meters observed to date. In the visible and near-infrared (0.4 to 2.4 µm) Bennu's spectrum appears featureless and with a blue (negative) slope, confirming previous ground-based observations. Bennu may represent a class of objects that could have brought volatiles and organic chemistry to Earth.

19.
Nat Commun ; 10(1): 1291, 2019 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-30890725

RESUMEN

During its approach to asteroid (101955) Bennu, NASA's Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft surveyed Bennu's immediate environment, photometric properties, and rotation state. Discovery of a dusty environment, a natural satellite, or unexpected asteroid characteristics would have had consequences for the mission's safety and observation strategy. Here we show that spacecraft observations during this period were highly sensitive to satellites (sub-meter scale) but reveal none, although later navigational images indicate that further investigation is needed. We constrain average dust production in September 2018 from Bennu's surface to an upper limit of 150 g s-1 averaged over 34 min. Bennu's disk-integrated photometric phase function validates measurements from the pre-encounter astronomical campaign. We demonstrate that Bennu's rotation rate is accelerating continuously at 3.63 ± 0.52 × 10-6 degrees day-2, likely due to the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect, with evolutionary implications.

20.
AJNR Am J Neuroradiol ; 40(3): 478-482, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30765380

RESUMEN

BACKGROUND AND PURPOSE: Patients with carbon monoxide (CO) intoxication exhibit progressive WM changes that are not well-understood. The purpose of this study was to detect longitudinal WM changes using voxelwise diffusional kurtosis imaging in patients with CO intoxication from the acute-to-chronic stage after CO intoxication. MATERIALS AND METHODS: Twenty-four patients with CO intoxication and 21 age- and sex-matched healthy controls were enrolled in this study. Diffusional kurtosis imaging was performed on all subjects and was conducted repeatedly in patients at 1 week and 1, 3, and 9 months after CO intoxication. Voxelwise diffusional kurtosis imaging analysis was performed to detect global WM changes in the patients with and without WM lesions. Receiver operating characteristic analysis was performed to compare the performance of diffusional indices in differentiating patients with delayed neuropsychiatric sequelae from patients without them. RESULTS: In voxelwise analysis, progressive WM changes were detected in patients with WM lesions. In the acute phase, WM injuries were found mainly in the dopaminergic pathways at 1 week, whereas in the chronic stage, WM injuries extended toward subcortical areas from 1 to 9 months. However, no significant WM change was noted in patients without WM lesions during the 9 months after CO intoxication. Moreover, receiver operating characteristic analysis demonstrated that axial kurtosis and mean kurtosis values had better performance than other diffusional indices in differentiating patients with delayed neuropsychiatric sequelae from patients without them at 1 week after CO intoxication. CONCLUSIONS: Voxelwise diffusional kurtosis imaging analysis was helpful to longitudinally investigate WM changes and predict the prognosis of patients after CO intoxication.


Asunto(s)
Encéfalo/diagnóstico por imagen , Intoxicación por Monóxido de Carbono/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Neuroimagen/métodos , Sustancia Blanca/diagnóstico por imagen , Adulto , Encéfalo/patología , Intoxicación por Monóxido de Carbono/patología , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Sustancia Blanca/patología
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