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1.
Sci Total Environ ; 934: 173350, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38772481

RESUMO

Gravel-sand mulch (GSM) and plastic film mulch (PFM) are important ways of farming in cold and arid regions without irrigation. Nevertheless, there has been a lack of studies of the system response to live weather conditions. To quantify the effects of GSM and PFM on soil moisture and temperature retention, in-situ monitoring experiments were carried out in the arid belt of central Ningxia, China, using continuous monitoring of the field soil water and meteorological conditions at a 30-mimute time-step under three treatments: a bare soil (CK), soil covered by a layer of GSM, and soil covered by GSM and a layer of plastic film (i.e., GSM + PFM). Results show that: (1) With a limited precipitation of 221 mm during the growing season, the average volumetric soil water content (SWC) in the top 30-cm soil layer was lowest for CK, medium high for GSM, and highest for GSM + PFM. Compared to CK, the soil water storage increased by 54 % under GSM and 75.2 % under GSM + PFM; (2) The most frequently occurring low-intensity rainfalls are more efficiently stored in soil under GSM + PFM; (3) Similarly, the soil temperature was significantly increased under GSM and GSM + PFM conditions. Compared to CK, the average soil temperature in the top 5-cm layer increased by 2.5 °C under GSM and 4.8 °C under GSM + PFM during the germination period, which had effectively extended the growing season for about 30 and 50 days, respectively; (4) Although dewfall is only 4 % of rainfall, the total number of dew day was more than twice that of rain day. Thus, dewfall is a more frequent and dependable source of water for native plants and animals. Our results demonstrate that the benefits of GSM and PFM can be applied globally where either insufficient rainfall or low temperatures are limiting factors.

2.
J Clin Med ; 13(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38610760

RESUMO

Background: Pulmonary hypertension (PH) patients are at higher risk of postoperative complications. We analyzed the association of PH with 30-day postoperative pulmonary complications (PPCs). Methods: A single-center propensity score overlap weighting (OW) retrospective cohort study was conducted on 164 patients with a mean pulmonary artery pressure (mPAP) of >20 mmHg within 24 months of undergoing elective inpatient abdominal surgery or endoscopic procedures under general anesthesia and a control cohort (N = 1981). The primary outcome was PPCs, and the secondary outcomes were PPC sub-composites, namely respiratory failure (RF), pneumonia (PNA), aspiration pneumonia/pneumonitis (ASP), pulmonary embolism (PE), length of stay (LOS), and 30-day mortality. Results: PPCs were higher in the PH cohort (29.9% vs. 11.2%, p < 0.001). When sub-composites were analyzed, higher rates of RF (19.3% vs. 6.6%, p < 0.001) and PNA (11.2% vs. 5.7%, p = 0.01) were observed. After OW, PH was still associated with greater PPCs (RR 1.66, 95% CI (1.05-2.71), p = 0.036) and increased LOS (median 8.0 days vs. 4.9 days) but not 30-day mortality. Sub-cohort analysis showed no difference in PPCs between pre- and post-capillary PH patients. Conclusions: After covariate balancing, PH was associated with a higher risk for PPCs and prolonged LOS. This elevated PPC risk should be considered during preoperative risk assessment.

3.
Blood Adv ; 8(8): 1908-1919, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38324722

RESUMO

ABSTRACT: Vaso-occlusive episodes (VOC) or pain crises are the most common indications for hematopoietic cell transplantation (HCT) for sickle cell disease (SCD). Elimination of pain crisis after HCT is an important patient-centered outcome and may improve understanding of the natural history of pain syndromes in SCD. We examined deidentified records of 763 patients followed-up for a median of 36.7 months (range, 0.3-168.6 months), with 69.6% patient's age <18 years at HCT, 83.3% patient's Karnofsky-Lansky performance score (KPS) ≥90, overall survival 92.9%, event-free survival 72.4%, graft failure (GF) 22.4%, AGVHD 21.4%, CGVHD 27%, and pain crisis 8.65%. On unadjusted logistic regression, increased risk of pain crisis after HCT was observed in patient's aged >10 years at HCT (range, 11-17 years; OR, 9.43; 95% CI, 3.20-27.79; P < .0001), in age ≥18 years (OR, 16.62; 95% CI, 5.85-47.16; P < .0001), in those with history of pain crisis 2 years before HCT (OR, 13.16; 95% CI, 4.08-42.42; P < .0001), alternate donors (haploidentical [OR, 4.80; 95% CI, 2.48-9.31; P < .0001], unrelated matched [OR, 2.71; 95% CI, 1.23-5.97; P = .0132], and mismatched unrelated [OR, 3.19; 95% CI, 1.44-7.05; P = .0041], and those with GF (n = 41 [5.37%]; OR, 7.15; 95% CI, 4.20-12.18; P < .0001). Pain crisis was less frequent with KPS of ≥90 (OR, 0.31; 95% CI, 0.18-0.55; P < .0001). Multivariable logistic regression models confirmed age at HCT, KPS, graft type, donor type, history of VOC 2 years before HCT, and GF as independent predictors of pain crisis after HCT and generated predictive models and nomograms for pain crisis after HCT for SCD, which can support shared decision making.


Assuntos
Anemia Falciforme , Transplante de Células-Tronco Hematopoéticas , Compostos Orgânicos Voláteis , Humanos , Incidência , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Dor/etiologia , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Fatores de Risco
4.
Med Res Arch ; 11(10)2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38037571

RESUMO

Background: Systemic sclerosis (SSc) is a rare autoimmune disorder with pathological manifestations affecting multiple organ systems. Few studies have examined perioperative outcomes in patients with this disorder. The primary aim of this retrospective single-center comparative cohort analysis was to estimate the incidence of select perioperative complications in a population of SSc patients. In an exploratory analysis, we analyzed the relationship between SSc and susceptibility to select perioperative complications when treated at a large quaternary-care institution. Methods: We conducted a single-center retrospective, comparative cohort study to compare perioperative outcomes in a SSc (n=258) and a frequency matched control cohort (n=632). We analyzed for the presence of major composite infection (MCI), major adverse cardiac events (MACE), 30-day readmission, 30-day mortality, in-hospital complications, length of stay and airway management outcomes. Results: MCI was higher in the SSc compared to the control cohort [adjusted odds ratio (ORadj)=5.02 (95%CI: 2.47-10.20) p<0.001]. Surgical site infection (3.5% vs. 0%, p<0.001), and other infection types (5% vs. 0%, p<0.001) were higher in the SSc cohort. MACE was not significantly different between SSc vs. Control groups [6.2% vs. 7.9%, ORadj=1.33 (95%CI: 0.61-2.91) p=0.48]. Higher rates of limited cervical range of motion (13.6% vs. 3.5%, p<0.001), microstomia (11.5% vs. 1.3%, p<0.001) and preoperative difficult airway designation (8.7% vs. 0.5%, p<0.001) were observed in the SSc cohort. Bag mask ventilation grade was similar between groups (p=0.44). After adjustment, there was no between-group difference in Cormack-Lehane grade 3 and 4 view on direct laryngoscopy in SSc patients [ORadj = 1.86 (95%CI: 0.612 -5.66) p=0.18] but evidence of higher rates of video laryngoscopy [ORadj= 1.87 (95%CI:1.07 - 3.27) p=0.03]. Length of stay [median: 0.2 vs. 0.3 days, p=0.08], 30-day mortality [1.2% vs. 0.6%, ORadj=2.79 (95%CI: 0.50-15.6) p=0.24] and readmission [11.5% vs. 8.1%, ORadj=1.64 (95%CI: 0.96 - 2.82) p=0.07] were not statistically significant. Conclusions: SSc patients demonstrate mostly similar rates of MACE, 30-day mortality, length of stay intraoperative and airway complications. There is evidence of increased risk of overall 30-day MCI risk and readmission after endoscopic procedures.

5.
Medicine (Baltimore) ; 102(50): e36363, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38115309

RESUMO

RATIONALE: Percutaneous transhepatic biliary drainage (PTBD) plays a significant role especially in the diagnosis and decompression of bile duct obstruction. However, it is associated with complications such as hemobilia, occlusion of drainage, bile leakage, and even bronchobiliary fistula (BBF). PATIENT CONCERNS AND DIAGNOSES: We herein describe a patient with a complication of BBF caused by long-term indwelling PTBD catheters. She underwent multiple operations including bilioenteric anastomosis, hepatic left lateral lobectomy, and long-term PTBD treatment. Her symptoms were mainly cough, fever, and yellow sputum and her diagnosis was confirmed by sputum culture (bilirubin detection was positive). INTERVENTIONS AND OUTCOMES: The patient recovered uneventfully by minimally invasive treatment, was discharged after 1 week of hospitalization, and the drainage tube was removed 2 weeks later. During 2 years of follow-up, no recurrence of BBF was observed. LESSONS: Patients with long-term indwelling PTBD catheters for biliary tract obstruction may lead to BBF. The treatment plan of BBF is tailored to the patient's individualized characteristics. And minimally invasive treatments might be an effective alternate way for the treatment of BBF. The accurate diagnosis, precision treatment, and multidisciplinary team play important roles in the treatment of BBF.


Assuntos
Fístula Biliar , Colestase , Humanos , Feminino , Fístula Biliar/diagnóstico , Fístula Biliar/etiologia , Fístula Biliar/cirurgia , Colestase/complicações , Drenagem/efeitos adversos , Catéteres/efeitos adversos , Anastomose Cirúrgica/efeitos adversos
6.
medRxiv ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38106157

RESUMO

Background: The inflammatory response within the central nervous system is a key driver of secondary brain injury after hemorrhagic stroke, both in patients with intracerebral hemorrhage (ICH) and aneurysmal subarachnoid hemorrhage (aSAH). In this study, we aimed to characterize inflammatory molecules in the blood and cerebrospinal fluid (CSF) of patients within 72 hours of hemorrhage to understand how such molecules vary across disease types and disease severity. Methods: Biological samples were collected from patients admitted to a single-center Neurosciences Intensive Care Unit with a diagnosis of ICH or aSAH between 2014 and 2022. Control CSF samples were collected from patients undergoing CSF diversion for normal pressure hydrocephalus. A panel of immune molecules in the plasma and CSF samples was analyzed using Cytometric Bead Array assays. Clinical variables, including demographics, disease severity, and intensive care unit length of stay were collected. Results: Plasma and/or CSF samples were collected from 260 patients (188 ICH patients, 54 aSAH patients, 18 controls). C-C motif chemokine ligand-2 (CCL2), interleukin-6 (IL-6), granulocyte-colony stimulating factor (G-CSF), interleukin-8 (IL-8), and vascular endothelial growth factor (VEGF), were detectable in the CSF within the first 3 days after hemorrhage, and all were elevated compared to plasma. Compared with controls, CCL2, IL-6, IL-8, G-CSF, and VEGF were elevated in the CSF of both ICH and aSAH patients (p<0.01 for all comparisons). VEGF was increased in ICH patients compared to aSAH patients (p<0.01). CCL2, G-CSF, and VEGF in the CSF were associated with more severe disease in aSAH patients only. Conclusions: Within 3 days of hemorrhagic stroke, proinflammatory molecules can be detected in the CSF at higher concentrations than in the plasma. Early concentrations of some pro-inflammatory molecules may be associated with markers of disease severity.

7.
Int J Biol Sci ; 19(13): 4340-4359, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705747

RESUMO

An essential pathogenic element of acute limb ischemia/reperfusion (I/R) injury is microvascular dysfunction. The majority of studies indicates that fibroblast growth factor 2 (FGF2) exhibits protective properties in cases of acute I/R injury. Albeit its specific role in the context of acute limb I/R injury is yet unknown. An impressive post-reperfusion increase in FGF2 expression was seen in a mouse model of hind limb I/R, followed by a decline to baseline levels, suggesting a key role for FGF2 in limb survivability. FGF2 appeared to reduce I/R-induced hypoperfusion, tissue edema, skeletal muscle fiber injury, as well as microvascular endothelial cells (ECs) damage within the limb, according to assessments of limb vitality, Western blotting, and immunofluorescence results. The bioinformatics analysis of RNA-sequencing revealed that ferroptosis played a key role in FGF2-facilitated limb preservation. Pharmacological inhibition of NFE2L2 prevented ECs from being affected by FGF2's anti-oxidative and anti-ferroptosis activities. Additionally, silencing of kruppel-like factor 2 (KLF2) by interfering RNA eliminated the antioxidant and anti-ferroptosis effects of FGF2 on ECs. Further research revealed that the AMPK-HDAC5 signal pathway is the mechanism via which FGF2 regulates KLF2 activity. Data from luciferase assays demonstrated that overexpression of HDAC5 prevented KLF2 from becoming activated by FGF2. Collectively, FGF2 protects microvascular ECs from I/R injury by KLF2-mediated ferroptosis inhibition and antioxidant responses.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Traumatismo por Reperfusão , Animais , Camundongos , Antioxidantes , Western Blotting , Células Endoteliais , Fator 2 de Crescimento de Fibroblastos/genética , Traumatismo por Reperfusão/genética
8.
Int Immunopharmacol ; 123: 110651, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37506502

RESUMO

Osteoarthritis (OA) is an age-related chronic degenerative disease with complex pathophysiological mechanisms. Accumulating evidence indicates that nod-like receptor pyrin domain 3 (NLRP3) inflammasome-mediated pyroptosis of chondrocytes plays a crucial role in the OA progression. Transient Receptor Potential Vanilloid 4 (TRPV4), described as a calcium-permeable cation channel, isassociated with proinflammatory factors and pyroptosis. In this study, we studied the potential functions of TRPV4 in chondrocyte pyroptosis and cartilage degradation. We found that lipopolysaccharides(LPS)-induced mitochondrial reactive oxygen species (mtROS) accumulation aggravated chondrocyte pyroptosis and cartilage degeneration. TRPV4 induces dynamin-related protein 1 (Drp1) mitochondrial translocation through the Ca2+-calmodulin-dependent protein kinase II (CaMKII) signaling pathway, which subsequently caused the mitochondrial dysfunction (e.g., mPTP over opening; Δψm depolarization; ATP production decreased; mtROS accumulation), pyroptosis and extracellular matrix (ECM) degradation through hexokinase 2 (HK2) dissociation from mitochondrial membrane. Moreover, TRPV4 inhibition reversed Drp1-involved chondrocyte pyroptosis and cartilage degeneration in the anterior cruciate ligament transection (ACLT) mouse model. Our findings revealed the internal mechanisms underlying TRPV4 regulation in chondrocytes and its intrinsic therapeutic efficacy for OA.


Assuntos
Osteoartrite , Piroptose , Animais , Camundongos , Cartilagem/metabolismo , Condrócitos/metabolismo , Hexoquinase , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Osteoartrite/metabolismo , Canais de Cátion TRPV/metabolismo
9.
PLoS One ; 18(4): e0283681, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37023098

RESUMO

It was recently shown that radiation, conduction and convection can be combined within a single Monte Carlo algorithm and that such an algorithm immediately benefits from state-of-the-art computer-graphics advances when dealing with complex geometries. The theoretical foundations that make this coupling possible are fully exposed for the first time, supporting the intuitive pictures of continuous thermal paths that run through the different physics at work. First, the theoretical frameworks of propagators and Green's functions are used to demonstrate that a coupled model involving different physical phenomena can be probabilized. Second, they are extended and made operational using the Feynman-Kac theory and stochastic processes. Finally, the theoretical framework is supported by a new proposal for an approximation of coupled Brownian trajectories compatible with the algorithmic design required by ray-tracing acceleration techniques in highly refined geometry.


Assuntos
Convecção , Temperatura Alta , Simulação por Computador , Fenômenos Físicos , Algoritmos , Método de Monte Carlo
10.
Theranostics ; 13(2): 849-866, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36632224

RESUMO

Background: Increasing evidence suggests that acute traumatic spinal cord injury (SCI)-induced defects in autophagy and autophagy-lysosomal pathway (ALP) may contribute to endothelial barrier disruption following injury. Recently, Kruppel-like factor 2 (KLF2) was reported as a key molecular switch on regulating autophagy. Whether KLF2 coordinates endothelial endothelial ALP in SCI is not known. Methods: Genetic manipulations of KLF2 were performed in bEnd.3 cells and SCI model. Western blot, qRT-PCR, immunofluorescence staining and Lyso-Tracker Red staining, Evans blue dye extravasation, behavioral assessment via Basso mouse scale (BMS), electrophysiology and footprint analysis were performed. Results: In SCI, autophagy flux disruption in endothelial cells contributes to TJ proteins degradation, leading to blood-spinal cord barrier (BSCB) impairment. Furthermore, the KLF2 level was decreased in SCI, overexpression of which alleviated TJ proteins loss and BSCB damage, which improve motor function recovery in SCI mice, while knockdown of KLF2 displayed the opposite effects. At the molecular level, KLF2 overexpression alleviated the TJ proteins degradation and the endothelial permeability by tuning the ALP dysfunction caused by SCI and oxygen glucose deprivation (OGD). Conclusions: Endothelial KLF2 as one of the key contributors to SCI-mediated ALP dysfunction and BSCB disruption. KLF2 could be a promising pharmacological target for the management and treatment of SCI.


Assuntos
Autofagia , Barreira Hematoencefálica , Fatores de Transcrição Kruppel-Like , Traumatismos da Medula Espinal , Animais , Camundongos , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/metabolismo , Fatores de Transcrição/metabolismo
11.
J Knee Surg ; 36(6): 631-636, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34952547

RESUMO

BACKGROUND: The aim of the study was to investigate the relationship between sarcopenia and both clinical and functional outcome scores following total knee arthroplasty (TKA) performed for patients over 65 years of age. METHODS: We assessed patient demographics, preoperative health status, postoperative Knee Society Clinical (KSS-C) and Function (KSS-F) subscores, and perioperative complications for 180 patients with sarcopenia and 345 comparatively healthy patients at a mean of 12.0 months after surgery. Multivariate logistic regression analysis was performed to define whether sarcopenia was an independent risk factor for lower KSS-F and KSS-C subscores and peroperative complication rates. Patients with sarcopenia had lower mean body mass index, preoperative albumin, and preoperative hemoglobin levels (p < 0.01). RESULTS: Compared with the healthy control group, patients with sarcopenia had lower KSS-C (83.0 vs. 88.2, p < 0.01) and KSS-F (79.2 vs. 86.1, p < 0.01) subscores and increased postoperative complication rates (14.1% vs. 4.1%, p < 0.01). CONCLUSION: Patients with sarcopenia present with generally poorer preoperative health and this appears to be associated with lower patient-reported clinical and functional outcome scores. Complication rates were higher among patients with sarcopenia who were still determined to have adequate health status to support TKA. Most complications were limited and could be managed with supportive treatment.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Sarcopenia , Humanos , Artroplastia do Joelho/efeitos adversos , Estudos Retrospectivos , Sarcopenia/complicações , Resultado do Tratamento , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/cirurgia
12.
Med Sci Monit ; 28: e938688, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36325822

RESUMO

This publication has been retracted by the Editor due to concerns regarding the originality of the figure images.Reference:Yongzeng Feng, Zili He, Cong Mao, Xiaolong Shui, Leyi Cai. Therapeutic Effects of Resveratrol Liposome on Muscle Injury in Rats. Med Sci Monit, 2019; 25:2377-2385. DOI: 10.12659/MSM.913409.

13.
Entropy (Basel) ; 24(7)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35885197

RESUMO

As an important task in computer vision, head pose estimation has been widely applied in both academia and industry. However, there remains two challenges in the field of head pose estimation: (1) even given the same task (e.g., tiredness detection), the existing algorithms usually consider the estimation of the three angles (i.e., roll, yaw, and pitch) as separate facets, which disregard their interplay as well as differences and thus share the same parameters for all layers; and (2) the discontinuity in angle estimation definitely reduces the accuracy. To solve these two problems, a THESL-Net (tiered head pose estimation with self-adjust loss network) model is proposed in this study. Specifically, first, an idea of stepped estimation using distinct network layers is proposed, gaining a greater freedom during angle estimation. Furthermore, the reasons for the discontinuity in angle estimation are revealed, including not only labeling the dataset with quaternions or Euler angles, but also the loss function that simply adds the classification and regression losses. Subsequently, a self-adjustment constraint on the loss function is applied, making the angle estimation more consistent. Finally, to examine the influence of different angle ranges on the proposed model, experiments are conducted on three popular public benchmark datasets, BIWI, AFLW2000, and UPNA, demonstrating that the proposed model outperforms the state-of-the-art approaches.

14.
Sensors (Basel) ; 22(14)2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35890933

RESUMO

Understanding learners' emotions can help optimize instruction sand further conduct effective learning interventions. Most existing studies on student emotion recognition are based on multiple manifestations of external behavior, which do not fully use physiological signals. In this context, on the one hand, a learning emotion EEG dataset (LE-EEG) is constructed, which captures physiological signals reflecting the emotions of boredom, neutrality, and engagement during learning; on the other hand, an EEG emotion classification network based on attention fusion (ECN-AF) is proposed. To be specific, on the basis of key frequency bands and channels selection, multi-channel band features are first extracted (using a multi-channel backbone network) and then fused (using attention units). In order to verify the performance, the proposed model is tested on an open-access dataset SEED (N = 15) and the self-collected dataset LE-EEG (N = 45), respectively. The experimental results using five-fold cross validation show the following: (i) on the SEED dataset, the highest accuracy of 96.45% is achieved by the proposed model, demonstrating a slight increase of 1.37% compared to the baseline models; and (ii) on the LE-EEG dataset, the highest accuracy of 95.87% is achieved, demonstrating a 21.49% increase compared to the baseline models.


Assuntos
Eletroencefalografia , Emoções , Atenção , Eletroencefalografia/métodos , Emoções/fisiologia , Humanos , Aprendizagem
15.
Sensors (Basel) ; 22(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35214248

RESUMO

The performance of a facial expression recognition network degrades obviously under situations of uneven illumination or partial occluded face as it is quite difficult to pinpoint the attention hotspots on the dynamically changing regions (e.g., eyes, nose, and mouth) as precisely as possible. To address the above issue, by a hybrid of the attention mechanism and pyramid feature, this paper proposes a cascade attention-based facial expression recognition network on the basis of a combination of (i) local spatial feature, (ii) multi-scale-stereoscopic spatial context feature (extracted from the 3-scale pyramid feature), and (iii) temporal feature. Experiments on the CK+, Oulu-CASIA, and RAF-DB datasets obtained recognition accuracy rates of 99.23%, 89.29%, and 86.80%, respectively. It demonstrates that the proposed method outperforms the state-of-the-art methods in both the experimental and natural environment.


Assuntos
Reconhecimento Facial , Face , Expressão Facial , Iluminação , Boca , Estimulação Luminosa
17.
Materials (Basel) ; 15(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35161059

RESUMO

The heat accumulation generated by microbial metabolic activities during the storage of the sawdust may lead to spontaneous combustion accidents. This paper studied the Critical Ambient Temperature (CAT) variation of poplar sawdust at different stack dimensions and investigated the physicochemical properties as well as microbial community dynamics during the self-heating process of poplar sawdust stacks. From the self-heating substances test experiments and Frank-Kamenetskii (FK) theory, it was found that the CAT of poplar sawdust stacks would decrease from 158.27 °C to 102.46 °C with the increase of stack size from 0.1 m to 3.2 m. From the sawdust stack self-heating experiments, microbial metabolic activities were enhanced with the increasing moisture content (by watering) and oxygen (by turning over), which led to a remarkable increase of the sawdust stack temperature and the rapid decomposition of biochemical components (especially cellulose and hemicellulose). From the microbiological community analysis, at the thermophilic stage (around 60 °C, large amounts of heat release in compost bin), the existence of thermostable bacteria (such as Brevibacillus thermoruber, Bacillus thermoamylovorans and Paenibacillus barengoltzii belonging to Firmicutes) played an important role in degrading organic substances. The heat generated by the microbial metabolic activities might lead to spontaneous combustion eventually if sawdust stack is large enough. Therefore, the sawdust should be stacked in a cool and dry area while avoiding large amounts of storage in high humidity environments.

18.
Acta Pharmacol Sin ; 43(6): 1360-1371, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34480113

RESUMO

Spinal cord injury (SCI) is one kind of severe trauma for central nervous system. Myelin debris clearance and axon regeneration are essential for nerve regeneration after SCI. Metformin, a glucose-lowering drug, has been demonstrated to promote the locomotor functional recovery after SCI. In this study, we investigated the role and molecular mechanism of metformin on myelin preservation in a rat SCI model. SCI was induced in rats by compression at T9 level using a vascular clip. We showed that administration of metformin (50 mg·kg-1·d-1, ip) for 28 days significantly improved locomotor function in SCI rats. Metformin also ameliorated SCI-induced neuronal apoptosis and promoted axon regeneration in the spinal cord. Using co-immunofluorescence of IBa-1 and MBP, and luxol fasting blue (LFB) staining, we demonstrated that metformin promoted the transformation of M1 to M2 phenotype polarization of microglial cells, then greatly facilitated myelin debris clearance and protected the myelin in SCI rats. Furthermore, metformin ameliorated SCI-induced blockade of autophagic flux in the spinal cord, and enhanced the fusion of autophagosome and lysosome by inhibiting the AMPK-mTOR signaling pathway. Moreover, metformin significantly attenuated inflammatory responses in the spinal cord. In LPS-treated BV2 cells, pretreatment with metformin (2 mM) significantly enhanced autophagy level, suppressed inflammation and cell apoptosis. The protective effects were blocked in the presence of an autophagy inhibitor 3-methyladenine (3-MA, 5 mM), suggesting that the effect of metformin on autophagy in microglial cells is essential for the myelin preservation during nerve recovery. This study reveals a novel therapeutic effect of metformin in SCI recovery by regulating the activation of microglial cells and enhancing its autophagy level.


Assuntos
Metformina , Traumatismos da Medula Espinal , Animais , Axônios/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Microglia , Bainha de Mielina/metabolismo , Regeneração Nervosa , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico
19.
Front Plant Sci ; 12: 513388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33584766

RESUMO

Phytophthora root rot, caused by Phytophthora sojae is a destructive disease of soybean (Glycine max) worldwide. We previously confirmed that the bHLH transcription factor GmPIB1 (P. sojae-inducible bHLH transcription factor) reduces accumulation of reactive oxygen species (ROS) in cells by inhibiting expression of the peroxidase-related gene GmSPOD thus improving the resistance of hairy roots to P. sojae. To identify proteins interacting with GmPIB1 and assess their participation in the defense response to P. sojae, we obtained transgenic soybean hairy roots overexpressing GmPIB1 by Agrobacterium rhizogenes mediated transformation and examined GmPIB1 protein-protein interactions using immunoprecipitation combined with mass spectrometry. We identified 392 proteins likely interacting with GmPIB1 and selected 20 candidate genes, and only 26S proteasome regulatory subunit GmPSMD (Genbank accession no. XP_014631720) interacted with GmPIB1 in luciferase complementation and pull-down experiments and yeast two-hybrid assays. Overexpression of GmPSMD (GmPSMD-OE) in soybean hairy roots remarkably improved resistance to P. sojae and RNA interference of GmPSMD (GmPSMD -RNAi) increased susceptibility. In addition, accumulation of total ROS and hydrogen peroxide (H2O2) in GmPSMD-OE transgenic soybean hairy roots were remarkably lower than those of the control after P. sojae infection. Moreover, in GmPSMD-RNAi transgenic soybean hairy roots, H2O2 and the accumulation of total ROS exceeded those of the control. There was no obvious difference in superoxide anion (O2 -) content between control and transgenic hairy roots. Antioxidant enzymes include peroxidase (POD), glutathione peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT) are responsible for ROS scavenging in soybean. The activities of these antioxidant enzymes were remarkably higher in GmPSMD-OE transgenic soybean hairy roots than those in control, but were reduced in GmPSMD-RNAi transgenic soybean hairy roots. Moreover, the activity of 26S proteasome in GmPSMD-OE and GmPIB1-OE transgenic soybean hairy roots was significantly higher than that in control and was significantly lower in PSMD-RNAi soybean hairy roots after P. sojae infection. These data suggest that GmPSMD might reduce the production of ROS by improving the activity of antioxidant enzymes such as POD, SOD, GPX, CAT, and GmPSMD plays a significant role in the response of soybean to P. sojae. Our study reveals a valuable mechanism for regulation of the pathogen response by the 26S proteasome in soybean.

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