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1.
Cell ; 173(1): 117-129.e14, 2018 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-29570992

RESUMEN

Angiogenesis, the formation of new blood vessels by endothelial cells (ECs), is an adaptive response to oxygen/nutrient deprivation orchestrated by vascular endothelial growth factor (VEGF) upon ischemia or exercise. Hypoxia is the best-understood trigger of VEGF expression via the transcription factor HIF1α. Nutrient deprivation is inseparable from hypoxia during ischemia, yet its role in angiogenesis is poorly characterized. Here, we identified sulfur amino acid restriction as a proangiogenic trigger, promoting increased VEGF expression, migration and sprouting in ECs in vitro, and increased capillary density in mouse skeletal muscle in vivo via the GCN2/ATF4 amino acid starvation response pathway independent of hypoxia or HIF1α. We also identified a requirement for cystathionine-γ-lyase in VEGF-dependent angiogenesis via increased hydrogen sulfide (H2S) production. H2S mediated its proangiogenic effects in part by inhibiting mitochondrial electron transport and oxidative phosphorylation, resulting in increased glucose uptake and glycolytic ATP production.


Asunto(s)
Factor de Transcripción Activador 4/metabolismo , Aminoácidos Sulfúricos/deficiencia , Sulfuro de Hidrógeno/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor de Transcripción Activador 4/antagonistas & inhibidores , Factor de Transcripción Activador 4/genética , Aminoácidos Sulfúricos/metabolismo , Animales , Cistationina gamma-Liasa/metabolismo , Modelos Animales de Enfermedad , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Isquemia/metabolismo , Isquemia/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica , Condicionamiento Físico Animal , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética
2.
Nature ; 572(7769): 341-346, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31367039

RESUMEN

Salinity is detrimental to plant growth, crop production and food security worldwide. Excess salt triggers increases in cytosolic Ca2+ concentration, which activate Ca2+-binding proteins and upregulate the Na+/H+ antiporter in order to remove Na+. Salt-induced increases in Ca2+ have long been thought to be involved in the detection of salt stress, but the molecular components of the sensing machinery remain unknown. Here, using Ca2+-imaging-based forward genetic screens, we isolated the Arabidopsis thaliana mutant monocation-induced [Ca2+]i increases 1 (moca1), and identified MOCA1 as a glucuronosyltransferase for glycosyl inositol phosphorylceramide (GIPC) sphingolipids in the plasma membrane. MOCA1 is required for salt-induced depolarization of the cell-surface potential, Ca2+ spikes and waves, Na+/H+ antiporter activation, and regulation of growth. Na+ binds to GIPCs to gate Ca2+ influx channels. This salt-sensing mechanism might imply that plasma-membrane lipids are involved in adaption to various environmental salt levels, and could be used to improve salt resistance in crops.


Asunto(s)
Arabidopsis/citología , Arabidopsis/metabolismo , Señalización del Calcio , Calcio/metabolismo , Glicoesfingolípidos/metabolismo , Células Vegetales/metabolismo , Cloruro de Sodio/metabolismo , Arabidopsis/genética , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Mutación , Estrés Salino/genética , Estrés Salino/fisiología , Cloruro de Sodio/farmacología , Intercambiadores de Sodio-Hidrógeno/metabolismo
3.
Mol Cancer ; 23(1): 90, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38711083

RESUMEN

BACKGROUND: Metabolic reprogramming and epigenetic alterations contribute to the aggressiveness of pancreatic ductal adenocarcinoma (PDAC). Lactate-dependent histone modification is a new type of histone mark, which links glycolysis metabolite to the epigenetic process of lactylation. However, the role of histone lactylation in PDAC remains unclear. METHODS: The level of histone lactylation in PDAC was identified by western blot and immunohistochemistry, and its relationship with the overall survival was evaluated using a Kaplan-Meier survival plot. The participation of histone lactylation in the growth and progression of PDAC was confirmed through inhibition of histone lactylation by glycolysis inhibitors or lactate dehydrogenase A (LDHA) knockdown both in vitro and in vivo. The potential writers and erasers of histone lactylation in PDAC were identified by western blot and functional experiments. The potential target genes of H3K18 lactylation (H3K18la) were screened by CUT&Tag and RNA-seq analyses. The candidate target genes TTK protein kinase (TTK) and BUB1 mitotic checkpoint serine/threonine kinase B (BUB1B) were validated through ChIP-qPCR, RT-qPCR and western blot analyses. Next, the effects of these two genes in PDAC were confirmed by knockdown or overexpression. The interaction between TTK and LDHA was identified by Co-IP assay. RESULTS: Histone lactylation, especially H3K18la level was elevated in PDAC, and the high level of H3K18la was associated with poor prognosis. The suppression of glycolytic activity by different kinds of inhibitors or LDHA knockdown contributed to the anti-tumor effects of PDAC in vitro and in vivo. E1A binding protein p300 (P300) and histone deacetylase 2 were the potential writer and eraser of histone lactylation in PDAC cells, respectively. H3K18la was enriched at the promoters and activated the transcription of mitotic checkpoint regulators TTK and BUB1B. Interestingly, TTK and BUB1B could elevate the expression of P300 which in turn increased glycolysis. Moreover, TTK phosphorylated LDHA at tyrosine 239 (Y239) and activated LDHA, and subsequently upregulated lactate and H3K18la levels. CONCLUSIONS: The glycolysis-H3K18la-TTK/BUB1B positive feedback loop exacerbates dysfunction in PDAC. These findings delivered a new exploration and significant inter-relationship between lactate metabolic reprogramming and epigenetic regulation, which might pave the way toward novel lactylation treatment strategies in PDAC therapy.


Asunto(s)
Carcinoma Ductal Pancreático , Regulación Neoplásica de la Expresión Génica , Glucólisis , Histonas , L-Lactato Deshidrogenasa , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/genética , Humanos , Histonas/metabolismo , Animales , Línea Celular Tumoral , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Ratones , Retroalimentación Fisiológica , Epigénesis Genética , Carcinogénesis/metabolismo , Carcinogénesis/genética , Pronóstico , Proliferación Celular , Femenino
4.
Int Wound J ; 20(6): 2075-2081, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36651223

RESUMEN

To investigate the influencing factors of lower limb amputation in patients with diabetic foot ulcers. Patients with diabetic foot ulcers who were hospitalised in a tertiary general hospital in Guizhou Province from January 2019 to March 2022 were retrospectively collected. Sociological information of the general population, comorbidities, laboratory-related indicators, and information on the specialty situation, using univariate analysis and multifactor analysis, compared the influencing factors of amputation and non-amputee patients. A total of 205 patients with diabetic foot and 69 ampute patients (33.7%) were enrolled. The univariate analysis found that the decrease in HDL cholesterol levels was associated with the occurrence of lower extremity amputation, and logistic stepwise regression analysis showed that HDL-C was inversely correlated with the amputation rate of patients with diabetic foot ulcers, and the risk of amputation at low levels of HDL-C was 2.452 times higher than that of high-level HDL-C (95% CI: 1.105-5.846). Decreased HDL cholesterol levels are an independent predictor of amputation in patients with diabetic foot ulcers.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Úlcera del Pie , Humanos , Pie Diabético/cirugía , Pie Diabético/epidemiología , Estudios Retrospectivos , HDL-Colesterol , Amputación Quirúrgica , Extremidad Inferior/cirugía , Factores de Riesgo
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(11): 1101-1106, 2023 Nov 15.
Artículo en Zh | MEDLINE | ID: mdl-37990452

RESUMEN

OBJECTIVES: To investigate the therapeutic efficacy of volume-guaranteed high frequency oscillation ventilation (HFOV-VG) versus conventional mechanical ventilation (CMV) in the treatment of preterm infants with respiratory failure. METHODS: A prospective study was conducted on 112 preterm infants with respiratory failure (a gestational age of 28-34 weeks) who were admitted to the Department of Neonatology, Jiangyin Hospital Affiliated to Medical School of Southeast University, from October 2018 to December 2022. The infants were randomly divided into an HFOV-VG group (44 infants) and a CMV group (68 infants) using the coin tossing method based on the mode of mechanical ventilation. The therapeutic efficacy was compared between the two groups. RESULTS: After 24 hours of treatment, both the HFOV-VG and CMV groups showed significant improvements in arterial blood pH, partial pressure of oxygen, partial pressure of carbon dioxide, and partial pressure of oxygen/fractional concentration of inspired oxygen ratio (P<0.05), and the HFOV-VG group had better improvements than the CMV group (P<0.05). There were no significant differences between the two groups in the incidence rate of complications, 28-day mortality rate, and length of hospital stay (P>0.05), but the HFOV-VG group had a significantly shorter duration of invasive mechanical ventilation than the CMV group (P<0.05). The follow-up at the corrected age of 6 months showed that there were no significant differences between the two groups in the scores of developmental quotient, gross motor function, fine motor function, adaptive ability, language, and social behavior in the Pediatric Neuropsychological Development Scale (P>0.05). CONCLUSIONS: Compared with CMV mode, HFOV-VG mode improves partial pressure of oxygen and promotes carbon dioxide elimination, thereby enhancing oxygenation and shortening the duration of mechanical ventilation in preterm infants with respiratory failure, while it has no significant impact on short-term neurobehavioral development in these infants.


Asunto(s)
Infecciones por Citomegalovirus , Ventilación de Alta Frecuencia , Síndrome de Dificultad Respiratoria del Recién Nacido , Insuficiencia Respiratoria , Lactante , Niño , Recién Nacido , Humanos , Recien Nacido Prematuro , Estudios Prospectivos , Edad Gestacional , Dióxido de Carbono , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Ventilación de Alta Frecuencia/métodos , Respiración Artificial , Insuficiencia Respiratoria/terapia , Oxígeno
6.
Small ; 18(12): e2105019, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34910848

RESUMEN

Light stimuli have notable advantages over other environmental stimuli, such as more precise spatial and temporal regulation, and the ability to serve as an energy source to power the system. In nature, photoresponsive nanochannels are important components of organisms, with examples including the rhodopsin channels in optic nerve cells and photoresponsive protein channels in the photosynthesis system of plants. Inspired by biological channels, scientists have constructed various photoresponsive, smart solid-state nanochannels membranes for a range of applications. In this review, the methods and applications of photosensitive nanochannels membranes are summarized. The authors believe that this review will inspire researchers to further develop multifunctional artificial nanochannels for applications in the fields of biosensors, stimuli-responsive smart devices, and nanofluidic devices, among others.


Asunto(s)
Técnicas Biosensibles
7.
J Neurol Neurosurg Psychiatry ; 93(6): 617-624, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35387867

RESUMEN

BACKGROUND: An unmet need remains for sensitive outcome measures in neuroprotective trials. The study aims to determine whether a composite clinical motor score, combining the Movement Disorders Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) III motor examination score, Purdue Pegboard Test, and Timed Up and Go, provides greater sensitivity in detecting motor change in early disease than the MDS-UPDRS III alone. METHODS: The Oxford Discovery longitudinal cohort study involves individuals with isolated rapid eye movement sleep behaviour disorder (iRBD) (n=272, confirmed polysomnographically, median follow-up: 1.6 years), idiopathic Parkinson's disease (PD) (n=909, median follow-up: 3.5 years, baseline: <3.5 years disease duration) and controls (n=316, age-matched and sex-matched, without a first-degree family history of PD). Motor and non-motor assessments were performed at each in-person visit. RESULTS: Compared with the MDS-UPDRS III, the composite clinical motor score demonstrated a wider score distribution in iRBD and controls, lower coefficient of variation (37% vs 67%), and higher correlation coefficients with self-reported measures of motor severity (0.65 vs 0.61) and overall health status (-0.40 vs -0.33). Greater score range in mild to moderate PD, higher magnitude of longitudinal change in iRBD and longitudinal score linearity suggest better sensitivity in detecting subtle motor change. The composite clinical motor score was more accurate than the MDS-UPDRS III in predicting clinical outcomes, requiring 64% fewer participants with PD and 51% fewer participants with iRBD in sample size estimations for a hypothetical 18-month placebo-controlled clinical trial. CONCLUSION: The composite clinical motor score may offer greater consistency and sensitivity in detecting change than the MDS-UPDRS III.


Asunto(s)
Enfermedad de Parkinson , Trastorno de la Conducta del Sueño REM , Humanos , Estudios Longitudinales , Pruebas de Estado Mental y Demencia , Evaluación de Resultado en la Atención de Salud , Enfermedad de Parkinson/diagnóstico , Índice de Severidad de la Enfermedad
8.
Artículo en Inglés | MEDLINE | ID: mdl-35732412

RESUMEN

OBJECTIVES: To explore the genetics of four Parkinson's disease (PD) subtypes that have been previously described in two large cohorts of patients with recently diagnosed PD. These subtypes came from a data-driven cluster analysis of phenotypic variables. METHODS: We looked at the frequency of genetic mutations in glucocerebrosidase (GBA) and leucine-rich repeat kinase 2 against our subtypes. Then we calculated Genetic Risk Scores (GRS) for PD, multiple system atrophy, progressive supranuclear palsy, Lewy body dementia, and Alzheimer's disease. These GRSs were regressed against the probability of belonging to a subtype in the two independent cohorts and we calculated q-values as an adjustment for multiple testing across four subtypes. We also carried out a Genome-Wide Association Study (GWAS) of belonging to a subtype. RESULTS: A severe disease subtype had the highest rates of patients carrying GBA mutations while the mild disease subtype had the lowest rates (p=0.009). Using the GRS, we found a severe disease subtype had a reduced genetic risk of PD (p=0.004 and q=0.015). In our GWAS no individual variants met genome wide significance (<5×10e-8) although four variants require further follow-up, meeting a threshold of <1×10e-6. CONCLUSIONS: We have found that four previously defined PD subtypes have different genetic determinants which will help to inform future studies looking at underlying disease mechanisms and pathogenesis in these different subtypes of disease.

9.
Biochem Genet ; 60(1): 382-394, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34235595

RESUMEN

Acute pancreatitis (AP) causes intestinal barrier damage, resulting in systemic inflammatory response syndrome (SIRS) or multiple organ dysfunction syndrome (MODS), which are important factors affecting AP severity and mortality. Here, we studied the mechanism of miR-122 in regulating intestinal barrier function in AP. AP rat model was constructed via intraperitoneal injection of ketamine, and primary intestinal epithelial cells were isolated from rats for in vitro studies. HE staining was used to assess pathological alterations of pancreas and intestines tissues. Inflammatory factors were detected by ELISA assay. qRT-PCR and WB were used to detect the expressions of miR-122 and occluding, respectively. Then dual-luciferase reporter assay, intestinal permeability test, and cell permeability were performed in vivo and in vitro to probe the molecular mechanism of miR-122 in regulating intestinal barrier function in AP. The expression of miR-122 was upregulated in AP rats, while the expression of occludin was downregulated, and the intestinal permeability was increased in AP rats and primary intestinal epithelial cells isolated from rats. Inhibition of miR-122 regulated intestinal barrier function through mediating occludin expression. miR-122 regulated intestinal barrier function to affect AP through mediating occludin expression in vivo. These results provided evidence that miR-122 overexpression impaired intestinal barrier function via regulation of occludin expression, thus promoting AP progression.


Asunto(s)
MicroARNs , Pancreatitis , Enfermedad Aguda , Animales , MicroARNs/genética , Ocludina/genética , Pancreatitis/genética , Permeabilidad , Ratas
10.
Ecotoxicol Environ Saf ; 242: 113903, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35870349

RESUMEN

Selenium incorporates into selenocysteine (Sec) which is a key component of selenoproteins implicated in antioxidant defense and redox homeostasis. Methionine sulfoxide reductases (Msr) play crucial roles in cellular defense against environmental stress. Whereas mammals have the MsrB selenoprotein form, unicellular organisms have MsrA. The Sec residue at the conserved catalytic sites of selenoprotein MsrA confers a metabolic advantage over the non-selenoprotein type MsrA. In the present study, the novel selenoprotein HpMsrA from Haematococcus pluvialis was cloned by the rapid amplification of cDNA ends and transformed into the model green alga Chlamydomonas reinhardtii. Alignment of homologs revealed the presence of the conserved catalytic domain GUFW and showed that the HpMsrA protein comprises Sec (U) at the N-terminus but no recycled Cys at the C-terminus. We studied the response of HpMsrA expression to selenite, high light intensity, hydrogen peroxide, cadmium nitrate, and glyphosate exposure via real-time quantitative PCR and enzyme activity analysis. The results demonstrated that HpMsrA protects cellular proteins against oxidative and environmental stressors. Compared with wild type C. reinhardtii, the transformant exhibited a superior antioxidant ability. The discoveries made herein shed light on the antioxidant physiology and environmental stress resistance mechanisms of the selenoproteins in microalgae. This information may aid in conducting environmental risk assessments of aquatic ecosystems involving microalgae known to respond rapidly and quantitatively to abiotic stress factors promoting excessive reactive oxygen species generation.


Asunto(s)
Antioxidantes , Metionina Sulfóxido Reductasas , Animales , Cadmio/toxicidad , Ecosistema , Glicina/análogos & derivados , Peróxido de Hidrógeno , Mamíferos/metabolismo , Metionina Sulfóxido Reductasas/genética , Metionina Sulfóxido Reductasas/metabolismo , Selenocisteína/metabolismo , Selenoproteínas/genética , Selenoproteínas/metabolismo , Glifosato
11.
Int J Mol Sci ; 23(5)2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35269647

RESUMEN

Dysregulation of type I interferons (IFNs) has been implicated in the pathogenesis of systemic lupus erythematosus (SLE) since the late 1970s. The majority of SLE patients demonstrate evidence of type I IFN pathway activation; however, studies attempting to address the relationship between type I IFN signature and SLE disease activity have yielded conflicting results. In addition to type I IFNs, type II and III IFNs may overlap and also contribute to the IFN signature. Different genetic backgrounds lead to overproduction of type I IFNs in SLE and contribute to the breakdown of peripheral tolerance by activation of antigen-presenting myeloid dendritic cells, thus triggering the expansion and differentiation of autoreactive lymphocytes. The consequence of the continuous stimulation of the immune system is manifested in different organ systems typical of SLE (e.g., mucocutaneous and cardiovascular involvement). After the discovery of the type I IFN signature, a number of different strategies have been developed to downregulate the IFN system in SLE patients, finally leading to the successful trial of anifrolumab, the second biologic to be approved for the treatment of SLE in 10 years. In this review, we will discuss the bench to bedside translation of the type I IFN pathway and put forward some issues that remain unresolved when selecting SLE patients for treatment with biologics targeting type I IFNs.


Asunto(s)
Interferón Tipo I , Lupus Eritematoso Sistémico , Diferenciación Celular , Humanos , Interferón Tipo I/metabolismo , Interferones/uso terapéutico
12.
Pancreatology ; 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34001437

RESUMEN

BACKGROUND: Surgical resection remains the only potentially curative treatment for pancreatic ductal adenocarcinoma (PDAC). However, a number of patients get disease recurred in a short time post-operation. Few studies have focused on the predictors of different recurrence patterns of PDAC. OBJECTIVE: To try to establish and verify a nomogram to predict recurrence free survival (RFS) in PDAC patients, and to distinguish the risk factors of local recurrence first and distant metastasis first via competing risk model. METHODS: Patients who underwent radical pancreatectomy for PDAC in our center from 2010 to 2018 were reviewed retrospectively. Kaplan-Meier methods and multivariate Cox regression analyses were used to identify the clinicopathological predictors of recurrence post-operation. And then, a nomogram was constructed and validated. Competing risk regression model was used to compare the predictors between local recurrence group and distant metastasis group. RESULTS: A total of 200 patients were included into the final analysis, and 153 patients got disease relapsed post-operation. CA19-9 level, vascular resection, tumor differentiation, lymph node ratio (LNR) and adjuvant chemotherapy were identified as independent risk factors for recurrence free survival (RFS) and incorporated into the nomogram. The C-index of the nomogram was 0.650. Competing risk model indicated that the status of lymph-node metastasis was significantly associated the patterns of first relapse. CONCLUSIONS: Nomogram and competing risk model were constructed to quantify the risk of recurrence following surgery for PDAC. Our findings may be useful for predicting RFS and recurrence pattern in clinical work.

13.
Sensors (Basel) ; 21(1)2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33406615

RESUMEN

Grain number per rice panicle, which directly determines grain yield, is an important agronomic trait for rice breeding and yield-related research. However, manually counting grains of rice per panicle is time-consuming, laborious, and error-prone. In this research, a grain detection model was proposed to automatically recognize and count grains on primary branches of a rice panicle. The model used image analysis based on deep learning convolutional neural network (CNN), by integrating the feature pyramid network (FPN) into the faster R-CNN network. The performance of the grain detection model was compared to that of the original faster R-CNN model and the SSD model, and it was found that the grain detection model was more reliable and accurate. The accuracy of the grain detection model was not affected by the lighting condition in which images of rice primary branches were taken. The model worked well for all rice branches with various numbers of grains. Through applying the grain detection model to images of fresh and dry branches, it was found that the model performance was not affected by the grain moisture conditions. The overall accuracy of the grain detection model was 99.4%. Results demonstrated that the model was accurate, reliable, and suitable for detecting grains of rice panicles with various conditions.


Asunto(s)
Aprendizaje Profundo , Oryza , Automatización , Grano Comestible , Fenotipo , Fitomejoramiento
14.
Entropy (Basel) ; 23(7)2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34202070

RESUMEN

Opportunistic beamforming (OBF) is an effective technique to improve the spectrum efficiencies (SEs) of multiple-input-multiple-output (MIMO) systems, which can obtain multiuser diversity gains with both low computation complexity and feedback information. To serve multiple users simultaneously, many multiple-access schemes have been researched in OBF. However, for most of the multiple-access schemes, the SEs are not satisfactory. To further improve the SE, this paper proposes a downlink multiuser OBF system, where both orthogonal frequency division multiplexing (OFDM) and non-orthogonal multiple-access (NOMA) methods are applied. The closed-form expressions of the equivalent channels and SE are derived in frequency selective fading channels. Then, an optimization problem is formulated to maximize the SE, although the optimization problem is non-convex and hard to solve. To obtain the solution, we divide the optimization problem into two suboptimal issues, and then a joint iterative algorithm is applied. In the proposed optimization scheme, the subcarrier mapping ϑ, user pairing knc and allocated power Pknc are determined to maximize spectrum efficiency (SE) and reduce bit error ratio (BER). According to numerical results, the proposed method achieves approximately 5 dB gain on both SE and BER, compared to the existing beamforming methods with low feedback information. Moreover, the SE of the proposed method is approximately 2 (bps/Hz) higher than sparse code multiple-access (SCMA), when the number of waiting users and the ratio of transmit power to noise variance are respectively 10 and 20 dB. It is indicated that the proposed scheme can achieve high and low BER with the limited feedback and computation complexity, regardless of the transmit power and the number of waiting users.

15.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(10): 987-993, 2021 Oct 15.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-34719412

RESUMEN

OBJECTIVES: To study the association of amplitude-integrated electroencephalogram (aEEG) and the quantitative indices biparietal width (BPW) and interhemispheric distance (IHD) of cranial magnetic resonance imaging (cMRI) with short-term neurodevelopment in moderately and late preterm infants. METHODS: A total of 104 moderately and late preterm infants who were admitted to the neonatal intensive care unit from September 2018 to April 2020 were selected as the subjects for this prospective study. The Naqeeb method and sleep-wake cycling (SWC) were used for aEEG assessment within 72 hours after birth. cMRI was performed at the corrected gestational age of 37 weeks. BPW and IHD were measured at the T2 coronal position. At the corrected age of 6 months, the Developmental Screening Test for Child Under Six (DST) was used to follow up neurodevelopment. According to developmental quotient (DQ), the infants were divided into a normal DST group (78 infants with DQ≥85) and an abnormal DST group (26 infants with DQ<85). Related indices were compared between the two groups. The association between aEEG and cMRI was evaluated. RESULTS: Compared with the normal DST group, the abnormal DST group had significantly lower aEEG normal rate and SWC maturation rate (P<0.05), as well as a significantly larger IHD and a significantly smaller BPW (P<0.05). Immature SWC, aEEG abnormality, and a relatively large IHD were the risk factors for abnormal DST (P<0.05), and a relatively large BPW was a protective factor against abnormal DST (P<0.05). CONCLUSIONS: For moderately and late preterm infants, aEEG within 72 hours after birth and the quantitative indices BPW and IHD of cMRI at the corrected gestational age of 37 weeks may affect their neurodevelopmental outcome at the corrected age of 6 months.


Asunto(s)
Electroencefalografía , Recien Nacido Prematuro , Edad Gestacional , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Estudios Prospectivos
16.
J Neurol Neurosurg Psychiatry ; 91(7): 703-711, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32354771

RESUMEN

Impulse control behaviours (ICBs) are a range of behaviours linked by their reward-based, repetitive natures. They can be precipitated in Parkinson's disease (PD) by dopamine replacement therapy, often with detrimental consequences for patients and caregivers. While now a well-recognised non-motor feature of treated PD, much remains unknown about the influence of risk factors, pathophysiological mechanisms, vulnerability factors for specific types of behaviour and the optimal management strategies. Imaging studies have identified structural and functional changes in striatal and prefrontal brain regions, among others. Gene association studies indicate a role for genetic predisposition to PD-ICB. Clinical observational studies have identified potential modifiable and non-modifiable risk factors. Psychological studies shed light on the neurocognitive domains implicated in PD-ICBs and identify psychosocial determinants that may perpetuate the cycle of impulsive and harm-avoidance behaviours. Based on these results, a range of pharmacological and non-pharmacological management strategies have been trialled in PD-ICBs with varying success. The purpose of this review is to update clinicians on the evidence around the pathophysiology of PD-ICB. We aim to translate our findings into an interpretable biopsychosocial model that can be applied to the clinical assessment and management of individual cases of PD-ICB.


Asunto(s)
Conducta Compulsiva/complicaciones , Trastornos Disruptivos, del Control de Impulso y de la Conducta/complicaciones , Enfermedad de Parkinson/complicaciones , Humanos , Conducta Impulsiva/fisiología , Factores de Riesgo
17.
Int J Mol Sci ; 21(17)2020 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-32842530

RESUMEN

Neurological disorders are the most devastating and challenging diseases associated with the central nervous system (CNS). The blood-brain barrier (BBB) maintains homeostasis of the brain and contributes towards the maintenance of a very delicate microenvironment, impairing the transport of many therapeutics into the CNS and making the management of common neurological disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), cerebrovascular diseases (CVDs) and traumatic brain injury (TBI), exceptionally complicated. Nanoparticle (NP) technology offers a platform for the design of tissue-specific drug carrying systems owing to its versatile and modifiable nature. The prospect of being able to design NPs capable of successfully crossing the BBB, and maintaining a high drug bioavailability in neural parenchyma, has spurred much interest in the field of nanomedicine. NPs, which also come in an array of forms including polymeric NPs, solid lipid nanoparticles (SLNs), quantum dots and liposomes, have the flexibility of being conjugated with various macromolecules, such as surfactants to confer the physical or chemical property desired. These nanodelivery strategies represent potential novel and minimally invasive approaches to the treatment and diagnosis of these neurological disorders. Most of the strategies revolve around the ability of the NPs to cross the BBB via various influx mechanisms, such as adsorptive-mediated transcytosis (AMT) and receptor-mediated transcytosis (RMT), targeting specific biomarkers or lesions unique to that pathological condition, thereby ensuring high tissue-specific targeting and minimizing off-target side effects. In this article, insights into common neurological disorders and challenges of delivering CNS drugs due to the presence of BBB is provided, before an in-depth review of nanoparticle-based theranostic strategies.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Nanomedicina/métodos , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Animales , Barrera Hematoencefálica/efectos de los fármacos , Lesiones Traumáticas del Encéfalo/diagnóstico , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/patología , Trastornos Cerebrovasculares/diagnóstico , Trastornos Cerebrovasculares/tratamiento farmacológico , Trastornos Cerebrovasculares/patología , Humanos , Nanopartículas/administración & dosificación , Nanopartículas/uso terapéutico , Enfermedades del Sistema Nervioso/patología , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/patología , Nanomedicina Teranóstica/métodos
18.
J Surg Res ; 235: 216-222, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30691797

RESUMEN

BACKGROUND: Dietary restriction (DR), defined as reduced nutrient intake without malnutrition, is associated with longevity extension, improved glucose metabolism, and increased stress resistance, but also poor wound healing. Short-term preoperative DR followed by a return to normal feeding after surgery results in improved surgical outcomes in preclinical models. However, the effect of preoperative DR on wound healing and perioperative glucose homeostasis is currently unknown. Here, we tested the effects of two different preoperative DR regimens-protein restriction (PR) and methionine restriction (MR)-on wound healing and perioperative glucose homeostasis using an established murine model of wound healing in both nondiabetic and diabetic mice. MATERIALS AND METHODS: Surgical outcomes were tested using the McFarlane flap in nondiabetic and streptozotocin-induced diabetic mice. Short-term dietary preconditioning included 1 wk of PR or MR diet (1-2 wk) versus an isocaloric complete diet before surgery; all mice were returned to a complete diet postoperatively. Outcome measures of flap wound recovery included skin viability and laser Doppler imaging of flap perfusion and assessment of CD45+ cell infiltration. Glucose homeostasis was assessed by glucose tolerance testing and by perioperative glucose levels in the diabetic cohort. RESULTS: No significant differences were observed in percentage of viable skin, perfusion, or immune cell infiltration at 7-10 d after surgery in PR or MR mice compared with controls in healthy or diabetic mice. Preoperative glucose tolerance and postoperative glucose levels were however significantly improved by both PR and MR in diabetic mice. CONCLUSIONS: Short-term dietary preconditioning with PR or MR did not impair wound healing in nondiabetic or diabetic mice. However, both regimens reduced preoperative hyperglycemia in diabetic mice. Thus, brief preoperative dietary manipulations stand as strategies to potentially improve perioperative hyperglycemia with no deleterious effects on wound healing in mice.


Asunto(s)
Dieta con Restricción de Proteínas/efectos adversos , Hiperglucemia/dietoterapia , Metionina , Cuidados Preoperatorios , Cicatrización de Heridas , Animales , Diabetes Mellitus Experimental/complicaciones , Hiperglucemia/etiología , Masculino , Ratones Endogámicos C57BL
19.
World J Surg ; 43(5): 1198-1206, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30659341

RESUMEN

BACKGROUND: Ingestion of jujube pits is a common clinical problem, which can be difficult to diagnose and life-threatening if accompanied with intestinal perforation and peritonitis. In this study, 18 cases of intestinal perforation caused by ingestion of jujube pits were reviewed and summarized to discuss the clinical characteristics, diagnosis and treatments. METHODS: From 2012 to 2018, a total of 18 patients diagnosed as intestinal perforation due to ingested pits of jujube in our center were retrospectively reviewed and the manifestations, laboratory tests, imaging examinations and treatment strategies were summarized. RESULTS: The patients comprised of 11 males and 7 females with an average age of 63.5 years. The main clinical manifestation was abdominal pain. Twelve patients (67%) presented to the emergency department with signs of localized peritonitis. CT imaging revealed positive findings in 17 (94%) patients. Conservative treatments were attempted in 3 patients, and the other 15 patients received emergency surgical exploration, where 7 patients had more than one perforation identified during surgery. Five patients were admitted in the surgical intensive care unit after surgery. The average length of stay of all 18 patients was 9.8 days (range 5-24 days). CONCLUSION: Ingestion of jujube pits is a common clinical problem and potentially leads to intestinal perforation and peritonitis. CT imaging is the first imaging modality of choice. Patients with milder symptoms might be managed with cautious conservative treatment, and patients with more than one perforation can be identified during surgery.


Asunto(s)
Cuerpos Extraños/complicaciones , Perforación Intestinal/etiología , Perforación Intestinal/cirugía , Ziziphus/efectos adversos , Dolor Abdominal/diagnóstico por imagen , Dolor Abdominal/etiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Cuerpos Extraños/diagnóstico por imagen , Cuerpos Extraños/cirugía , Humanos , Perforación Intestinal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Peritonitis/diagnóstico por imagen , Peritonitis/etiología , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
Sensors (Basel) ; 19(8)2019 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-31010148

RESUMEN

Automatic and efficient plant leaf geometry parameter measurement offers useful information for plant management. The objective of this study was to develop an efficient and effective leaf geometry parameter measurement system based on the Android phone platform. The Android mobile phone was used to process and measure geometric parameters of the leaf, such as length, width, perimeter, and area. First, initial leaf images were pre-processed by some image algorithms, then distortion calibration was proposed to eliminate image distortion. Next, a method for calculating leaf parameters by using the positive circumscribed rectangle of the leaf as a reference object was proposed to improve the measurement accuracy. The results demonstrated that the test distances from 235 to 260 mm and angles from 0 to 45 degrees had little influence on the leafs' geometric parameters. Both lab and outdoor measurements of leaf parameters showed that the developed method and the standard method were highly correlated. In addition, for the same leaf, the results of different mobile phone measurements were not significantly different. The leaf geometry parameter measurement system based on the Android phone platform used for this study could produce high accuracy measurements for leaf geometry parameters.

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