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1.
J Diabetes Investig ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563225

RESUMEN

AIMS/INTRODUCTION: The aim of the present study was to evaluate the status of glycemic control, and assess the effects of the disease course and comprehensive management measures on the blood glucose level in children and adolescents with type 2 diabetes mellitus. MATERIALS AND METHODS: The study collected the clinical data of type 2 diabetes patients in Beijing Children's Hospital from January 2015 to September 2020. Patients were grouped based on the disease course to compare their glycated hemoglobin (HbA1c) level, islet ß-cell function, insulin resistance and comprehensive management measures. RESULTS: Of the 170 participants, the median disease course was 2.0 years (interquartile range [IQR] 1.0-4.0 years). The baseline HbA1c was 11.2% (IQR 9.2-12.4%). According to the grouping by the disease course, the median HbA1c was the lowest (5.7% [IQR 5.3-6.1%]) in the half-year course group and the highest in the 4-year course group (9.0 [IQR 6.8%-11.3%]). Compared with the group with a disease duration <2 years, patients in the >4 years group had a lower proportion of patients with HbA1c <7% (29.2% vs 66.2%), a lower homeostasis model assessment of ß-cell function, and a lower proportion with a controlled diet, moderate-intensity exercise, regular follow up and no drug treatment. We deemed HbA1c as the dependent variable, and found that disease duration, homeostasis model assessment of ß-cell function at follow up, continuous moderate-intensity exercise, regular review and treatment regimen were significant influencing factors for glycemic control. CONCLUSIONS: Children and adolescents with type 2 diabetes and a prolonged disease course showed poor glycemic control and decreased islet ß-cell function. A good lifestyle, especially moderate-intensity exercise, can help such cases better control their blood glucose level.

2.
Molecules ; 28(19)2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37836703

RESUMEN

Hydrogen energy from solar water-splitting is known as an ideal method with which to address the energy crisis and global environmental pollution. Herein, the first-principles calculations are carried out to study the photocatalytic water-splitting performance of single-layer GaInSe3 under biaxial strains from -2% to +2%. Calculations reveal that single-layer GaInSe3 under various biaxial strains has electronic bandgaps ranging from 1.11 to 1.28 eV under biaxial strain from -2% to +2%, as well as a completely separated valence band maximum and conduction band minimum. Meanwhile, the appropriate band edges for water-splitting and visible optical absorption up to ~3 × 105 cm-1 are obtained under biaxial strains from -2% to 0%. More impressively, the solar conversion efficiency of single-layer GaInSe3 under biaxial strains from -2% to 0% reaches over 30%. The OER of unstrained single-layer GaInSe3 can proceed without co-catalysts. These demonstrate that single-layer GaInSe3 is a viable material for solar water-splitting.

3.
Phys Chem Chem Phys ; 25(15): 10335-10342, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36987986

RESUMEN

Recently, two-dimensional (2D) layered polarized ZnIn2S4 nanosheets have been successfully synthesized in experiments. However, the polarized monolayers are unstable in air, which hinders their practical applications. Therefore, in this work, we proposed a new family of nonpolarized monolayers (ß2-phase) ZnX2Z4 (X = In, Al, and Ga; Z = S, Se, and Te) by first-principles. It is confirmed that the energies of ß2-phase ZnX2Z4 are lower than those of the polarized and ß-phase ZnX2Z4 monolayers. Moreover, these ZnX2Z4 monolayers have not only desirable indirect band gaps but also high electron mobility (up to 103 cm2 V-1 s-1), revealing a fascinating visible light absorption range. Furthermore, ß2-phase ZnX2Te4 (X = In, Al, and Ga) has ultra-low lattice thermal conductivity and high ZT value (up to 0.89), suggesting that these monolayers can be good candidates for thermoelectric materials. These new 2D ternary monolayers not only effectively broaden the family of 2D materials but also provide promising candidates for optoelectronic and thermoelectric materials.

4.
Balkan Med J ; 40(3): 175-181, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-36960944

RESUMEN

Background: T-cell death-associated gene 51 (TDAG51) belongs to the transcription factor family and is involved in the energy homeostasis of the liver through the regulation of lipogenesis. Aims: To evaluate the role of T-cell death-associated gene 51 in gestational diabetes mellitus. Study Design: Experimental animal and human-sample study. Methods: A total of 30 patients with GDM were enrolled in the study. TDAG51 expression in patients with gestational diabetes mellitus was assessed by Western blotting and quantitative reverse-transcription polymerase chain reaction. A high-fat and high-sugar diet was used to establish a gestational diabetes mellitus model. Mice with gestational diabetes were injected with lentivirus-mediated overexpression of TDAG51. Blood glucose was measured using a glucometer, and glucose and insulin tolerance tests were performed to detect insulin resistance. Liver and adipose tissues were subjected to hematoxylin-eosin staining. Cell apoptosis was detected by TUNEL staining. Human villous trophoblast cells (HTR-8/SVneo) were treated with a high-glucose medium to induce gestational diabetes mellitus. Results: TDAG51 was downregulated in gestational diabetes mellitus and high glucose-induced HTR-8/SVneo. TDAG51 overexpression reduced the level of blood glucose, enhanced serum insulin, and attenuated glucose and insulin tolerance in gestational diabetes mellitus mice. TDAG51 overexpression also ameliorated impaired lipid metabolism and alleviated adipocyte hypertrophy and hepatic lipid droplets in gestational diabetes mellitus mice. The expressions of SREBP-1 and ANGPTL8 were upregulated in gestational diabetes mellitus and showed a negative correlation with TDAG51 in patients with gestational diabetes mellitus. TDAG51 increased the expressions of SREBP-1 and ANGPTL8 in gestational diabetes mellitus mice. TDAG51 overexpression reduced cell apoptosis and enhanced cell viability of high glucose-induced HTR-8/SVneo. Ectopic expression of ANGPTL8 attenuated the TDAG51-induced increase in cell viability and decrease in apoptosis in high glucose-induced HTR-8/SVneo. Conclusion: TDAG51 alleviated impaired lipid metabolism and insulin resistance in gestational diabetes mellitus via downregulation of SREBP 1/ANGPTL8 pathway.


Asunto(s)
Diabetes Gestacional , Resistencia a la Insulina , Insulinas , Hormonas Peptídicas , Embarazo , Femenino , Humanos , Ratones , Animales , Diabetes Gestacional/genética , Resistencia a la Insulina/genética , Metabolismo de los Lípidos , Glucemia , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Glucosa , Insulinas/metabolismo , Proteína 8 Similar a la Angiopoyetina , Hormonas Peptídicas/metabolismo
5.
J Neuroinflammation ; 20(1): 82, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36944982

RESUMEN

BACKGROUND: Central post-stroke pain (CPSP) is an intractable and disabling central neuropathic pain that severely affects patients' lives, well-being, and socialization abilities. However, CPSP has been poorly studied mechanistically and its treatment remains challenging. Here, we used a rat model of CPSP induced by thalamic hemorrhage to investigate its underlying mechanisms and the effect of stellate ganglion block (SGB) on CPSP and emotional comorbidities. METHODS: Thalamic hemorrhage was produced by injecting collagenase IV into the ventral-posterolateral nucleus (VPL) of the right thalamus. The up-and-down method with von Frey hairs was used to measure the mechanical allodynia. Behavioral tests were carried out to examine depressive and anxiety-like behaviors including the open field test (OFT), elevated plus maze test (EPMT), novelty-suppressed feeding test (NSFT), and forced swim test (FST). The peri-thalamic lesion tissues were collected for immunofluorescence, western blotting, and enzyme-linked immunosorbent assay (ELISA). Genetic knockdown of thalamic hypoxia-inducible factor-1α (HIF-1α) and NOD-like receptor thermal protein domain associated protein 3 (NLRP3) with microinjection of HIF-1α siRNA and NLRP3 siRNA into the VPL of thalamus were performed 3 days before collagenase injection into the same regions. Microinjection of lificiguat (YC-1) and MCC950 into the VPL of thalamus were administrated 30 min before the collagenase injection in order to inhibited HIF-1α and NLRP3 pharmacologically. Repetitive right SGB was performed daily for 5 days and laser speckle contrast imaging (LSCI) was conducted to examine cerebral blood flow. RESULTS: Thalamic hemorrhage caused persistent mechanical allodynia and anxiety- and depression-like behaviors. Accompanying the persistent mechanical allodynia, the expression of HIF-1α and NLRP3, as well as the activities of microglia and astrocytes in the peri-thalamic lesion sites, were significantly increased. Genetic knockdown of thalamic HIF-1α and NLRP3 significantly attenuated mechanical allodynia and anxiety- and depression-like behaviors following thalamic hemorrhage. Further studies revealed that intra-thalamic injection of YC-1, or MCC950 significantly suppressed the activation of microglia and astrocytes, the release of pro-inflammatory cytokines, the upregulation of malondialdehyde (MDA), and the downregulation of superoxide dismutase (SOD), as well as mechanical allodynia and anxiety- and depression-like behaviors following thalamic hemorrhage. In addition, repetitive ipsilateral SGB significantly restored the upregulated HIF-1α/NLRP3 signaling and the hyperactivated microglia and astrocytes following thalamic hemorrhage. The enhanced expression of pro-inflammatory cytokines and the oxidative stress in the peri-thalamic lesion sites were also reversed by SGB. Moreover, LSCI showed that repetitive SGB significantly increased cerebral blood flow following thalamic hemorrhage. Most strikingly, SGB not only prevented, but also reversed the development of mechanical allodynia and anxiety- and depression-like behaviors induced by thalamic hemorrhage. However, pharmacological activation of thalamic HIF-1α and NLRP3 with specific agonists significantly eliminated the therapeutic effects of SGB on mechanical allodynia and anxiety- and depression-like behaviors following thalamic hemorrhage. CONCLUSION: This study demonstrated for the first time that SGB could improve CPSP with comorbid anxiety and depression by increasing cerebral blood flow and inhibiting HIF-1α/NLRP3 inflammatory signaling.


Asunto(s)
Accidente Cerebrovascular Hemorrágico , Neuralgia , Accidente Cerebrovascular , Ratas , Animales , Hiperalgesia/tratamiento farmacológico , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Accidente Cerebrovascular Hemorrágico/complicaciones , Accidente Cerebrovascular Hemorrágico/patología , Depresión/etiología , Depresión/terapia , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Ganglio Estrellado/metabolismo , Ganglio Estrellado/patología , Ratas Sprague-Dawley , Accidente Cerebrovascular/patología , Tálamo/metabolismo , Hemorragia Cerebral/patología , Neuralgia/metabolismo , Ansiedad , Colagenasas/metabolismo , Citocinas/metabolismo
6.
Phys Chem Chem Phys ; 25(5): 4230-4235, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36661111

RESUMEN

The grain boundaries (GBs) composed of pentagons and octagons (558 GBs) have been demonstrated to induce attractive transport properties such as Van Hove singularity (VHS) and quasi-one-dimensional metallic wires. Here, we propose a monolayer carbon allotrope which is formed from the introduction of periodic 558 GBs to decorate intact graphene, termed as PHO-graphene. The calculated electronic properties indicate that PHO-graphene not only inherits the previously superior characteristics such as Van Hove singularity and quasi-one-dimensional metallic wires, but also possesses two twisted Dirac cones near the Fermi level. Further calculation finds that the Berry phase is quantized to ± π at the two Dirac points, which is consistent with the distribution of the corresponding Berry curvature. The parity argument uncovers that PHO-graphene hosts a nontrivial band topology and the edge states connecting the two Dirac points are clearly visible. Our findings not only provide a reliable avenue to realize the abundant and extraordinary properties of carbon allotropes, but also offer an attractive approach for designing all carbon-based devices.

7.
Mol Neurobiol ; 60(4): 2086-2098, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36602702

RESUMEN

Central post-stroke pain (CPSP) is a highly refractory form of central neuropathic pain that has been poorly studied mechanistically. Recent observations have emphasized the critical role of the spinal dorsal horn in CPSP. However, the underlying mechanisms remain unclear. In this study, rats were subjected to thalamic hemorrhage to investigate the role of spinal monocyte chemoattractant protein-1 (MCP-1) and C-C motif chemokine receptor 2 (CCR2) in the development of CPSP. Immunohistochemical staining and ELISA were used to assess the expression changes of c-Fos, Iba-1, GFAP, MCP-1, and CCR2 in the dorsal horn of the lumbar spinal cord following thalamic hemorrhage, and the involvement of spinal MCP-1 in CPSP was examined by performing intrathecal anti-MCP-1 mAb injection to neutralize the spinal extracellular MCP-1. We demonstrated that intra-thalamic collagenase microinjection induced persistent bilateral mechanical pain hypersensitivity and facilitated the spontaneous pain behaviors evoked by intraplantar bee venom injection. Accompanying CPSP, the expression of c-Fos, Iba-1, and GFAP in the lumbar spinal dorsal horn was significantly increased up to 28 days post-intra-thalamic collagenase microinjection. Intrathecal injection of minocycline and fluorocitrate dramatically reverses the bilateral mechanical pain hypersensitivity. Moreover, intra-thalamic collagenase microinjection dramatically induced the up-regulation of MCP-1 but had no effect on the expression of CCR2 in the bilateral lumbar spinal dorsal horn, and MCP-1 was primarily localized in the neuron. Intrathecal injection of anti-MCP-1 mAb was also able to reverse CPSP and reduce the expression of c-Fos, Iba-1, and GFAP in the lumbar spinal dorsal horn. These findings indicated that spinal MCP-1 contributes to CPSP by mediating the activation of spinal neurons and glial cells following thalamic hemorrhage stroke, which may provide insights into pharmacologic treatment for CPSP.


Asunto(s)
Quimiocina CCL2 , Neuralgia , Ratas , Animales , Quimiocina CCL2/metabolismo , Sensibilización del Sistema Nervioso Central , Ratas Sprague-Dawley , Hiperalgesia/metabolismo , Neuralgia/metabolismo , Médula Espinal/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo
8.
Neurotoxicology ; 93: 173-185, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36209936

RESUMEN

Due to the increasing use of local anesthetic techniques in various healthcare settings, local anesthetic toxicity still occurs. Seizures are the most common symptom of local anesthetic toxicity. The relationship between local anesthetic-induced seizures and the sensation of pain has not been established till now. Here, we assessed the development of pain hypersensitivity after ropivacaine-induced seizures (RIS) and the influence of RIS on incision-induced postsurgical pain and formalin-induced acute inflammatory pain. In addition, the involvement of spinal 5-HT/5-HT3R in RIS-induced pain sensitization was investigated. According to a sequential exploratory experimental strategy, we first calculated the 50% seizure dosage of ropivacaine to be 42.66 mg/kg (95% confidence interval: 40.19-45.28 mg/kg). We showed that RIS induced significant bilateral mechanical pain hypersensitivity that lasted around 5 days, accompanied by an increase in spinal 5-HT. Moreover, RIS considerably protracted postsurgical pain and enhanced formalin-induced spontaneous flinching in the second phase. Depletion of spinal 5-HT with intrathecal injection of 5,7-dihydroxytryptamine (5,7-DHT) reduced RIS-induced pain hypersensitivity and prevented the prolonging of postsurgical pain following RIS. Likewise, blocking spinal 5-HT3R by intrathecal administration of ondansetron reversed RIS-induced pain hypersensitivity and attenuated the pronociception of RIS in the formalin test. Our findings revealed that acute RIS led to pain hypersensitivity and had pronociceptive effects on incision-induced postsurgical pain and formalin-induced acute inflammatory pain. Moreover, our data implied that RIS-induced pain sensitization depends on spinal 5-HT/5-HT3R signaling. Thus, targeting the descending serotonergic facilitation system should be an important element of the precise treatment for local anesthetic toxicity.


Asunto(s)
Anestésicos Locales , Serotonina , Ratas , Animales , Serotonina/farmacología , Ropivacaína/farmacología , Anestésicos Locales/toxicidad , Médula Espinal , Formaldehído/toxicidad , Dolor Postoperatorio/tratamiento farmacológico , Convulsiones/inducido químicamente
9.
Front Pediatr ; 10: 973920, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36186652

RESUMEN

Background: The PTPN11 gene, located at 12q24. 13, encodes protein tyrosine phosphatase 2C. Mutations in the PTPN11 gene can lead to various phenotypes, including Noonan syndrome and LEOPARD syndrome. The SEC24D gene is located at 4q26 and encodes a component of the COPII complex, and is closely related to endoplasmic reticulum protein transport. Mutations in SEC24D can lead to Cole-Carpenter syndrome-2. To date, dual mutations in these two genes have not been reported in the literature. Methods: We report a patient with short stature and osteogenesis imperfecta as the primary clinical manifestation. Other clinical features were peculiar facial features, deafness, and a history of recurrent fractures. Whole exome sequencing was performed on this patient. Results: After whole-exome sequencing, three mutations in two genes were identified that induced protein alterations associated with the patient's phenotype. One was a de novo variant c.1403C>T (p.Thr468Met) on exon 12 of the PTPN11 gene, and the other was a compound heterozygous mutation in the SEC24D gene, a novel variant c.2609_2610delGA (p.Arg870Thrfs*10) on exon 20 and a reported variant c.938G>A (p.Arg313His) on exon 8. Conclusions: Concurrent mutations in PTPN11 and SEC24D induced a phenotype that was significantly different from individual mutations in either PTPN11 or SEC24D gene. Personalized genetic analysis and interpretation could help us understand the patient's etiology and hence develop treatments and improve the prognosis of these patients.

10.
Dis Markers ; 2022: 9073043, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36124028

RESUMEN

Method: A retrospective selection of 93 women who were hospitalized in our hospital from March 2019 to May 2022 with a singleton pregnancy and delivered at term with macrosomia were the study group. And 356 women who delivered a normal size baby during the same period were the control group. The variables that were associated with the onset of macrosomia were screened from maternal medical records. Logistic regression models, random forest, and CART decision tree models were developed using the screened variables as input variables and whether they were macrosomia as outcome variables, respectively. The performance of the three models was evaluated by accuracy, precision, recall, F1 score, and receiver operating characteristic curve (ROC). Result: The risk prediction models for the onset of macrosomia, logistic regression model, random forest model, and decision tree, were successfully developed, with accuracies of 0.904, 1.000, and 0.901 in the training set and 0.926, 0.582, and 0.852 in the validation set, respectively. The AUC in the training set were 0.898, 1.000, and 0.789, and in the validation set were 0.906, 0.913, and 0.731, respectively. In general, the logistic regression model has the highest diagnostic efficiency, followed by the random forest model. Conclusion: Logistic regression models have high application value in the assessment of predicting the risk of macrosomia, and it is suggested that the advantages of logistic regression models and random forest models should be combined in future studies and applications to make them work better in the prediction of the risk of macrosomia.


Asunto(s)
Macrosomía Fetal , Femenino , Macrosomía Fetal/diagnóstico , Humanos , Modelos Logísticos , Embarazo , Curva ROC , Estudios Retrospectivos
11.
Am J Transl Res ; 14(7): 4821-4829, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35958451

RESUMEN

To explore the diagnostic specificity and clinical application of neonatal umbilical cord blood gas analysis in the prognosis of fetal distress, and to provide theoretical basis for neonatal rescue. Clinical data of a total of 240 singleton pregnant women and their neonates who delivered in the Obstetrics Department of our hospital from January 2021 to December 2021 were retrospectively analyzed. The pregnant women and their newborns were divided into an acute group (acute fetal distress), a chronic group (chronic fetal distress) and a control group (no fetus distress), with 80 cases in each. The umbilical artery blood gas analysis values including power of hydrogen (PH), partial pressure of carbon dioxide (PCO2), partial pressure of oxygen (PO2), bicarbonate radical (HCO3 -), buffer excess (BE) and the Apgar score, as well as the neonatal asphyxia outcome after birth were recorded. There were statistically significant differences in fetal condition, PH and BE between newborns with asphyxia and normal newborns (P<0.05). The incidence of neonatal distress was 1.25% in the control group and 19.38% in the fetal distress group (including acute and chronic groups). Logistic regression analysis found that fetal distress was a risk factor for neonatal asphyxia (Odds Ratio (OR)=11.064, P=0.012). The specificity and sensitivity of neonatal cord blood gas analysis in diagnosing neonatal asphyxia were 95.69% and 80.65%, respectively. The specificity of Apgar score in the diagnosis of neonatal asphyxia was 94.74%, and the sensitivity was 70.97%. The rate of neonatal asphyxia in the chronic fetal distress group (26.25%) was higher than that in the acute fetal distress group (12.5%). The proportion of neonatal severe asphyxia in the chronic fetal distress group (66.67%) was higher than that in the acute group (20%). The PH and BE levels in the chronic fetal distress group were lower than those in the control group and acute fetal distress group (P<0.05). Cord blood gas analysis can help to improve the accuracy of fetal distress diagnosis. Cord blood gas is closely related to neonatal prognosis. Compared with acute fetal distress, chronic fetal distress is more likely to lead to neonatal acidosis and asphyxia.

12.
J Phys Chem Lett ; 13(24): 5508-5513, 2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35695758

RESUMEN

Two-dimensional (2D) boron nitride (BN) is a promising candidate for aerospace materials due to its excellent mechanical and thermal stability properties. However, its unusually prominent band gap limits its application prospects. In this work, we report a gapless monolayer BN, t-BN, which has four anisotropic Dirac cones in the first Brillouin zone exactly at the Fermi level. To further confirm the semimetallic character, the nontrivial topological properties are proven through the topologically protected edge states and the invariant non-zero Z2. Additionally, the Young's modulus and Poisson ratio characterize the strong mechanical strength of t-BN. Our theoretical predictions provide more possibilities for exploring the Dirac cone in BN, which will enhance the 2D boron derivative materials.

13.
Front Psychol ; 12: 760328, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34867660

RESUMEN

Under the background of "mass entrepreneurship and innovation," entrepreneurship and innovation for college students not only alleviates the current social employment pressure but also sets off the upsurge of their entrepreneurship. It is a significant field to research the entrepreneurial intention of undergraduates as potential entrepreneurs, which covers the study of entrepreneurial intention from the perspective of personal traits and entrepreneurial cognition. This article studies entrepreneurial intention from two aspects: irrational positive emotions and rational entrepreneurial cognition, which aims to reveal the mechanism of positive emotions and entrepreneurial cognition on entrepreneurial intention. After investigating 288 college students participating in entrepreneurial competitions, establishing structural equations, and using SmartPLS software for data analysis, the research result showed that positive emotions significantly positively impact the three scripts of entrepreneurial cognition: arrangement scripts, willing scripts, and ability scripts. The arrangement, willing, and ability scripts positively influence entrepreneurial intention, while positive emotions do not affect entrepreneurial intention. Arrangement scripts and ability scripts have a full mediating effect between positive emotions and entrepreneurial intention. Based on these findings, we provide suggestions for the government and society, schools, and individual students on innovation and entrepreneurship.

14.
J Phys Chem Lett ; 12(44): 10874-10879, 2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34730356

RESUMEN

The exploration of carbon phases with intact massless Dirac fermions in the presence of defects is critical for practical applications to nanoelectronics. Here, we identify by first-principles calculations that the Dirac cones can exist in graphene with stacking fault (SF) induced periodic line defects. These structures are width (n)-dependent to graphene nanoribbon and are thus termed as (SF)n-graphene. The electronic properties reveal that the semimetallic features with Dirac cones occur in (SF)n-graphene with n = 3m + 1, where m is a positive integer, and then lead to a quasi-one-dimensional conducting channel. Importantly, it is found that the twisted Dirac cone in the (SF)4-graphene is tunable among type-I, type-II, and type-III through a small uniaxial strain. The further stability analysis shows that (SF)n-graphene is thermodynamic stable. Our findings provide an artificial avenue for exploring Dirac Ffermions in carbon-allotropic structures in the presence of defects.

15.
J Phys Chem Lett ; 12(43): 10574-10580, 2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34694815

RESUMEN

We systematically study the giant anisotropic optoelectronics in layered PbSnX2 (X = S/Se). The highly anisotropic optoelectronics mainly originates from the asymmetric sublattices SnX, resulting in the anisotropy of photoelectronic properties with fascinating visible light absorption range in single-layer and bilayer PbSnX2. We employ uniaxial strain in both the x and y directions and find an indirect-to-direct band gap transition, while the quasiparticle indirect band gap presents excellent linear scaling with biaxial strain in monolayer PbSnX2. We also demonstrate ultrahigh anisotropic mobilities of electrons (µy > µx) and holes (µx > µy) in both single-layer and bilayer PbSnX2 (X = S/Se), and spin-orbit coupling effects and the increase of layer number significantly reduce exciton binding energies and band gaps. Finally, the strong layer dependence of the band structure is clearly seen when the film thickness is less than 4 layers. Our results provide a fundamental understanding of highly anisotropic PbSnX2 (X = S/Se) and show two potential candidates in photoelectric applications.

16.
BMJ Open ; 11(10): e051892, 2021 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-34667009

RESUMEN

INTRODUCTION: Patients with obstructive sleep apnoea (OSA) are more sensitive to postanaesthesia respiratory depression. Whether different anaesthetic regimens (intravenous-based or inhalational-based general anaesthesia) affect the postanaesthesia respiratory depression is controversial. Although desflurane has been reported that presents favourable rapid recovery profile in special patients including whom with OSA, the strong clinical evidence of the benefit on postanaesthesia respiratory depression is far from being revealed. This study aims to fill this knowledge gap by investigating the postanaesthesia respiratory depression in postanaesthesia care unit (PACU) in patients with OSA after major abdominal surgery, followed by desflurane-based anaesthesia compared with propofol-based anaesthesia. METHODS AND ANALYSIS: Eight hundred and fifty-four patients with OSA scheduled for elective major abdominal surgery will be randomly 1:1 assigned to desflurane-based (n=427) or propofol-based anaesthesia (n=427) using a computer-generated randomisation scheme with permuted block size maintained by a centralised randomisation centre. Patients will be assessed before and a consecutive 3 days after their surgery according to the standardised tasks. Demographic data as well as surgical and anaesthesia information will be collected for the duration of the procedure. Incidence of postanaesthesia respiratory depression in PACU as well as anaesthesia recovery, emergence delirium, postoperative nausea and vomiting, rescue analgesia, duration of PACU and hospital stay, and any other adverse events will be assessed at the given study time point. Investigators performing postoperative follow-up are not involved in both anaesthesia implementation and postoperative care. ETHICS AND DISSEMINATION: This study protocol has been approved by the ethics board at Xiang'an Hospital of Xiamen University (XAHLL2019003). The results of this study will be published in a peer-review journal and presented at national conferences as poster or oral presentations. Participants wishing to know the results of this study will be contacted directly on data publication. TRIAL REGISTRATION NUMBER: ChiCTR2000031087.


Asunto(s)
Anestésicos por Inhalación , Propofol , Insuficiencia Respiratoria , Apnea Obstructiva del Sueño , Anestesia General , Anestésicos Intravenosos , Desflurano , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Insuficiencia Respiratoria/inducido químicamente
17.
Nanoscale ; 13(43): 18267-18272, 2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34714316

RESUMEN

The exploration of novel two-dimensional semimetallic materials is always an attractive topic. We propose a series of two-dimensional silicon carbides with a tetragonal lattice. The band structure of silicon carbides with tetragonal carbon rings and silicon rings exhibits Dirac cones. Interestingly, the Dirac cone of tetragonal SiC originates from a "ring coupling" mechanism. This mechanism refers to the mutual coupling between the four carbon atoms in the tetragonal C ring, and the same coupling in the tetragonal Si ring. Additionally, the "ring coupling" mechanism is applicable to other group IV binary compounds such as monolayer GeC and SnC. This work provides reliable evidence for the argument that two-dimensional tetragonal materials can produce Dirac cones.

18.
Eur J Pharmacol ; 908: 174322, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34256084

RESUMEN

Neuropathic pain is a common chronic pain condition with major impact on quality of life. However, its physiopathologic mechanism remains unknown and pain management is still a challenge. Accumulating evidence indicated that C-X-C chemokine receptor type 4 (CXCR4) played a critical role in the process of pain. Thus, the present study aimed to investigate whether intervertebral foramen injection of CXCR4 antagonist, plerixafor, was able to relieve neuropathic pain and explore the possible underlying mechanism. Chronic compression of the dorsal root ganglion (CCD) was established as a typical model of neuropathic pain. The results indicated that CCD induced multiple pain-related behaviors and the expression of CXCR4, Nav1.8 and Nav1.9 was significantly increased in compressed dorsal root ganglion (DRG) neurons. Knocking down CXCR4 expression could significantly reduce neuropathic pain and intervertebral foramen plerixafor injection (IVFP) dramatically decreased the up-regulation of Nav1.8 and Nav1.9 and attenuated neuropathic pain. The analgesic duration of IVFP was maintained at least for 24 h which was much longer than intervertebral foramen injection of Nav1.8 blocker and local anesthetics. Therefore, our study provided evidence that IVFP could reduce the expression of Nav1.8 and Nav1.9 in DRG neurons which might contribute to, at least in part, the analgesic effect of plerixafor on CCD-induced neuropathic pain. It is concluded that IVFP was an effective and applicable treatment approach for neuropathic pain.


Asunto(s)
Regulación hacia Abajo , Ganglios Espinales , Animales , Bencilaminas , Ciclamas , Compuestos Heterocíclicos , Hiperalgesia , Masculino , Neuralgia , Calidad de Vida , Ratas
19.
Eur J Pharmacol ; 907: 174267, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34146590

RESUMEN

Ulinastatin is a broad-spectrum protease inhibitor widely used for the treatment of various inflammation-related diseases owing to its recognized excellent anti-inflammatory and cytoprotective properties. However, whether ulinastatin can relieve postoperative pain remains unclear. In this study, we evaluated the analgesic effects of ulinastatin administered either as a single agent or in combination with sufentanil in a validated preclinical rat model of postoperative pain induced by plantar incision. We found that incisional surgery on the hind paw of these rats induced sustained ipsilateral mechanical pain hypersensitivity that lasted for at least 10 days. A single intraperitoneal (i.p.) injection of ulinastatin prevented the development and reversed the maintenance of incision-induced mechanical pain hypersensitivity in a dose-dependent manner. However, ulinastatin had no effect on the baseline nociceptive threshold. Moreover, repeated i.p. injections of ulinastatin persistently attenuated incision-induced mechanical pain hypersensitivity and promoted recovery from the surgery. The rats did not develop any analgesic tolerance over the course of repeated injections of ulinastatin. A single i.p. injection of ulinastatin was also sufficient to inhibit the initiation and maintenance of incision-induced hyperalgesic priming when the rats were subsequently challenged with an ipsilateral intraplantar prostaglandin E2 injection. Furthermore, the combined administration of ulinastatin and sufentanil significantly enhanced the analgesic effect of sufentanil on postoperative pain, which involved mechanisms other than a direct influence on opioid receptors. These findings demonstrated that ulinastatin had a significant analgesic effect on postoperative pain and might be a novel pharmacotherapeutic agent for managing postoperative pain either alone or as an adjuvant.


Asunto(s)
Sufentanilo , Analgésicos , Animales , Glicoproteínas , Hiperalgesia , Umbral del Dolor , Dolor Postoperatorio , Ratas
20.
PLoS One ; 16(6): e0252960, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34106997

RESUMEN

This paper analyzes the option coordination problem of a fresh agricultural product supply chain under two supply chain structures, when the production cost and the loss rate are disrupted simultaneously. This paper provides the explicit option coordination conditions for the disrupted supply chain under two supply chain structures, and then explores the effects of the disruptions and supply chain structure on the option coordination conditions. The results suggest that it is unfavorable to apply the original coordinating contracts without disruptions to coordinate the disrupted supply chain. The coordination of the disrupted supply chain can be achieved with knowledge of the distribution of demand. In two coordinating contracts for the disrupted supply chain, the exercise price is still at the original level without disruptions while the option price deviates from the original level without disruptions. Moreover, the relationships of the coordination conditions in two supply chain structures depend on the value of the profit allocation coefficient. When the profit allocation coefficient exceeds (falls behind) a certain threshold, the option price is set at a higher (lower) value in the supplier-led supply chain structure than in the distributor-led supply chain structure, while the exercise price is set at a lower (higher) value in the supplier-led supply chain structure than in the distributor-led supply chain structure. Finally, the disrupted supply chain with any supply chain structure will perform better in the modified coordinating contracts than in the original coordinating contracts without disruptions.


Asunto(s)
Agricultura/organización & administración , Algoritmos , Comercio/economía , Contratos/economía , Costos y Análisis de Costo , Abastecimiento de Alimentos/economía , Comercio/métodos , Comportamiento del Consumidor , Contratos/normas , Abastecimiento de Alimentos/normas , Humanos
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