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1.
Adv Sci (Weinh) ; 10(2): e2202448, 2023 01.
Article En | MEDLINE | ID: mdl-36453576

The guanine nucleotide exchange factor (GEF) SOS1 catalyzes the exchange of GDP for GTP on RAS. However, regulation of the GEF activity remains elusive. Here, the authors report that PPDPF functions as an important regulator of SOS1. The expression of PPDPF is significantly increased in pancreatic ductal adenocarcinoma (PDAC), associated with poor prognosis and recurrence of PDAC patients. Overexpression of PPDPF promotes PDAC cell growth in vitro and in vivo, while PPDPF knockout exerts opposite effects. Pancreatic-specific deletion of PPDPF profoundly inhibits tumor development in KRASG12D -driven genetic mouse models of PDAC. PPDPF can bind GTP and transfer GTP to SOS1. Mutations of the GTP-binding sites severely impair the tumor-promoting effect of PPDPF. Consistently, mutations of the critical amino acids mediating SOS1-PPDPF interaction significantly impair the GEF activity of SOS1. Therefore, this study demonstrates a novel model of KRAS activation via PPDPF-SOS1 axis, and provides a promising therapeutic target for PDAC.


Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Animals , Mice , Carcinoma, Pancreatic Ductal/genetics , Guanine Nucleotide Exchange Factors/genetics , Guanine Nucleotide Exchange Factors/metabolism , Guanosine Triphosphate , Intracellular Signaling Peptides and Proteins , Pancreatic Neoplasms/genetics , Proto-Oncogene Proteins p21(ras)/genetics , SOS1 Protein , Pancreatic Neoplasms
2.
Sensors (Basel) ; 22(18)2022 Sep 16.
Article En | MEDLINE | ID: mdl-36146372

A method based on the high-frequency ultrasonic guided waves (UGWs) of a piezoelectric sensor array is proposed to monitor the depth of transverse cracks in rail bottoms. Selecting high-frequency UGWs with a center frequency of 350 kHz can enable the monitoring of cracks with a depth of 3.3 mm. The method of arranging piezoelectric sensor arrays on the upper surface and side of the rail bottom is simulated and analyzed, which allows the comprehensive monitoring of transverse cracks at different depths in the rail bottom. The multi-value domain features of the UGW signals are further extracted, and a back propagation neural network (BPNN) is used to establish the evaluation model of the transverse crack depth for the rail bottom. The optimal evaluation model of multi-path combination is reconstructed with the minimum value of the root mean square error (RMSE) as the evaluation standard. After testing and comparison, it was found that each metric of the reconstructed model is significantly better than each individual path; the RMSE is reduced to 0.3762; the coefficient of determination R2 reached 0.9932; the number of individual evaluation values with a relative error of less than 10% and 5% accounted for 100% and 87.50% of the total number of evaluations, respectively.


Neural Networks, Computer , Ultrasonics , Monitoring, Physiologic , Ultrasonic Waves
3.
Neurosurg Rev ; 45(3): 2277-2287, 2022 Jun.
Article En | MEDLINE | ID: mdl-35106677

Optic pathway glioma (OPG) is a rare brain tumor affecting children, with no standard treatment strategy. This study described the sporadic OPG survival outcomes after surgical treatment and analyzed the role of imaging features and resection status in children receiving different adjuvant treatments. This retrospective study included 165 OPG patients whose clinical information were obtained from the hospital record system. Tumor volume and residual tumor volume were calculated by delineating the lesion area. Kaplan-Meier method and Cox proportional hazards model were conducted to analyze the independent prognosis factor. A total of 165 patients were included in this study. Respectively, the 5-year overall survival (OS) and progression-free survival (PFS) were 87.58% and 77.87%. Residual tumor size and first adjuvant treatment (AT) after surgery were both associated with PFS. In patients with small-size residual tumors, there was no significant difference in PFS between the AT treatment groups. Moreover, age, exophytic cystic components, leptomeningeal metastases, and AT were associated with OS. In patients with exophytic cystic components and those with leptomeningeal metastases, there was no significant difference in OS. Our results revealed that OPG patients could avoid or defer AT by maximized resection. Age ≤ 2 years was a disadvantageous factor for OS. Patients with exophytic cystic components were more likely to benefit from primary surgery, and CT or RT was not beneficial for these patients. Patients with leptomeningeal metastases had a poor prognosis regardless of the treatment they received. Future prospective clinical studies are needed to develop more effective treatment regimens.


Brain Neoplasms , Optic Nerve Glioma , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Child , Child, Preschool , Disease-Free Survival , Humans , Neoplasm, Residual , Optic Nerve Glioma/surgery , Prognosis , Retrospective Studies
4.
Nanoscale Res Lett ; 16(1): 60, 2021 Apr 12.
Article En | MEDLINE | ID: mdl-33846860

Both multilayered (ML) and few-layered (FL) Ti3C2Tx nanosheets have been prepared through a typical etching and delaminating procedure. Various characterizations confirm that the dominant terminal groups on ML-Ti3C2Tx and FL-Ti3C2Tx are different, which have been assigned to O-related and hydroxyl groups, respectively. Such deviation of the dominant terminals results in the different physical and chemical performance and eventually makes the nanosheets have different potential applications. In particular, before coupling to Ag nanoparticles, ML-Ti3C2Tx can present stronger near-field enhancement effect; however, Ag/FL-Ti3C2Tx hybrid structure can confine stronger near-field due to the electron injection, which can be offered by the terminated hydroxyl groups.

5.
PeerJ ; 8: e9720, 2020.
Article En | MEDLINE | ID: mdl-32864221

Polychlorinated biphenyls (PCBs), particularly low chlorinated congeners in our environment, can induce human hepatotoxicity. However, the mechanisms by which PCBs cause hepatotoxicity remain elusive. Moreover, there are no effective treatments for this condition. In this study, 40 µM PCB52 was administered to rat (Brl-3A) and human hepatocytes (L-02) for 48 h following the N-acetylcysteine (NAC)/saline pretreatment. A significant decrease in cell viability was observed in PCB52-treated cells relative to the control. Besides, PCB52 significantly increased reactive oxygen species (ROS) levels and malondialdehyde (MDA) contents, suggesting induction of oxidative stress. The expression of Traf6, MyD88, and Tnf in Brl-3A cells and that of MYD88, TNF, and IL1B in L-02 cells were significantly upregulated by PCB52. Consistently, overexpression of TLR4, MyD88, Traf6, and NF-κB p65 proteins was observed in PCB52-treated cells, indicating activation of inflammatory responses. Nevertheless, no changes in kelch-like ECH-associated protein 1 (keap1), nuclear factor-erythroid 2-related factor (nrf2), and heme oxygenase-1 proteins were observed in PCB52-treated cells, indicating non-activation of the keap1/nrf2 pathway. Pretreatment with NAC significantly ameliorated PCB52 effects on cell viability, ROS levels, MDA contents and expression of inflammatory elements at both RNA and protein levels. However, no changes in keap1, nrf2 and HO-1 protein levels were detected following NAC pretreatment. Taken together, with non-activated keap1/nrf2 pathway, PCB52-induced oxidative stress and inflammatory responses could be responsible for its hepatotoxicity. These effects were effectively attenuated by NAC pretreatment, which scavenges ROS and dampens inflammatory responses. This study might provide novel strategies for the treatment of the PCBs-associated hepatotoxic effects.

6.
Front Neurol ; 11: 502, 2020.
Article En | MEDLINE | ID: mdl-32582014

Parkinson's disease (PD) is a chronic neurodegenerative disease with complex motor and non-motor symptoms often leading to significant caregiver burden. An integrated, multidisciplinary care setup involving different healthcare professionals is the mainstay in the holistic management of PD. Many challenges in delivering multidisciplinary team (MDT) care exist, such as insufficient expertise among different healthcare professionals, poor interdisciplinary collaboration, and communication. The need to attend different clinics, incurring additional traveling and waiting time for allied health therapies can also make MDT care more burdensome. By shifting MDT care to local community settings and into patients' homes, patient-centered care can be achieved. In Singapore, the National Neuroscience Institute created the Community Care Partners Programme in 2007 to bring the allied MDT team to the community and nurse-led Integrated Community Care Programme for Parkinson's Disease in 2012 to provide care in community and at patient's home. However, attaining MDT care in the community setting is difficult to achieve where there is a shortage of PD-trained professionals. As such, interdisciplinary and transdisciplinary management would be other best practice options to deliver patient-centric care in PD. Telemedicine could be another viable option to bring the MDT closer to the patient.

7.
Environ Pollut ; 264: 114715, 2020 Sep.
Article En | MEDLINE | ID: mdl-32402713

Polychlorinated biphenyls (PCBs) in the air are predominantly the less chlorinated congeners. Non-dioxin-like (NDL) low-chlorinated PCBs are more neurotoxic, and cause neurodevelopmental and neurobehavioral alterations in humans. However, the underlying mechanisms for this neurodevelopmental toxicity remain unknown. In the present study, Wistar rats were treated by gavage with PCB52 (1 mg/kg body weight) or corn oil from gestational day 7 to postnatal day 21. Both the body lengths and weights of the suckling rats at birth were significantly decreased by PCB52 treatment, suggesting developmental toxicity. Although no obvious histopathological changes were observed in the brain, using RNA-sequencing, 208 differentially expressed genes (DEGs) were identified in the striatum of PCB52-treated male offspring, while just 13 DEGs were identified in female offspring, suggesting sex-specific effects. Furthermore, using Gene Ontology enrichment analysis, neurodevelopmental processes, neurobehavioral alterations, and neurotransmission changes were enriched from the 208 DEGs in male offspring. Similarly, using Kyoto Encyclopedia of Genes and Genomes enrichment analysis, neuroactive ligand receptor interactions and multiple synapse pathways were enriched in male offspring, implying dysfunction of the neurotransmission system. Reductions in the protein expressions of these ligand receptors were also identified in the striatum, cerebral cortex, and hippocampus using western blotting methods. Taken together, our findings indicate that PCB52 exposure during gestation and lactation results in the abnormal expression of neurotransmission ligand-receptors in male offspring with a sex bias, and that this may contribute to neurodevelopmental toxicity.


Polychlorinated Biphenyls , Animals , Brain , Female , Humans , Lactation , Male , Rats , Rats, Wistar , Synaptic Transmission
8.
Nat Plants ; 6(4): 360-367, 2020 04.
Article En | MEDLINE | ID: mdl-32231254

Temperature-sensitive genic male sterility (TGMS) lines are widely used in the breeding of hybrid crops1,2, but by what means temperature as a general environmental factor reverses the fertility of different TGMS lines remains unknown. Here, we identified an Arabidopsis TGMS line named reversible male sterile (rvms) that is fertile at low temperature (17 °C) and encodes a GDSL lipase. Cytological observations and statistical analysis showed that low temperature slows pollen development. Further screening of restorers of rvms, as well as crossing with a slow-growth line at normal temperature (24 °C), demonstrate that slowing of development overcomes the defects of rvms microspores and allows them to develop into functional pollen. Several other Arabidopsis TGMS lines were identified, and their fertility was also restored by slowing of development. Given that male reproductive development is conserved3, we propose that slowing of development is a general mechanism applicable to the sterility-fertility conversion of TGMS lines from different plant species.


Arabidopsis/physiology , Thermotolerance , Arabidopsis/genetics , Arabidopsis/growth & development , Arabidopsis/ultrastructure , Cold Temperature , Fertility/genetics , Gene Expression Profiling , Gene-Environment Interaction , Genes, Plant , Mutation , Plant Development/genetics , Plant Development/physiology , Pollen/genetics , Pollen/growth & development , Thermotolerance/genetics
9.
RSC Adv ; 10(35): 20445-20459, 2020 May 27.
Article En | MEDLINE | ID: mdl-35517758

An insufficient drug concentration at the target site and drug efflux resulting in poor efficacy are recognized as important obstacles in osteoporosis treatment. Simvastatin (SIM), which can treat osteoporosis by promoting osteoblast differentiation and mineralization through the bone morphogenetic proteins (BMP)-Smad signaling pathway, has lower bioavailability, and less bone tissue distribution. Herein, novel lipid nanoparticles (LNPs) delivering SIM (SIM/LNPs) for osteoporosis therapy were developed with aspartic oligopeptide (ASP n , here ASP6)-based bone-targeting moieties grafted to the nanoparticles (SIM/ASP6-LNPs) in an attempt to increase the concentration of SIM in bones with a relatively low dose to minimize adverse effects. In vivo experiments indicated that the ASP6-LNPs exhibited ideal bone-targeting characteristics, and in vitro cell evaluation experiments showed LNPs have good biocompatibility with MC3T3-E1 cells. The cell mineralization experiment revealed that the SIM-loaded LNPs induced osteoblast differentiation and the formation of mineralized nodules in MC3T3-E1 cells, achieving the same efficacy as that of SIM. Pharmacodynamic experiments revealed that SIM/ASP6-LNPs improved the efficacy of SIM on the recovery of bone mineral density when compared to SIM/LNPs or to SIM alone. Therefore, SIM/ASP6-LNPs may represent a potential bone-targeting drug delivery system (DDS) that contributes to the development of a novel osteoporosis treatment.

11.
Ying Yong Sheng Tai Xue Bao ; 31(8): 2604-2612, 2020 Aug.
Article Zh | MEDLINE | ID: mdl-34494782

To clarify the effects of increased density and reduced nitrogen on greenhouse gas emission in double-season paddy fields under the water-saving and simple cultivation mode, we used Luliangyou 996 (early rice) and Fengyuanyou 299 (late rice) as materials to collect greenhouse gas by closed static box method, monitored the dynamics of CH4 and N2O emissions from different combinations of increased density and reduced nitrogen for early and late rice, and explored changes in cumulative CH4 and N2O emissions, global warming potential (GWP) and greenhouse gas intensity (GHGI) as affected by different combinations of increased density and reduced nitrogen from double-season rice fields. The results showed that the cumulative emissions of CH4 and N2O from different combinations were significantly different. Compared with the control (CK), cumulative CH4 emission, GWP and GHGI in the two seasons decreased by 50.8%, 37.3%, and 42.9% for the combination of increased density and reduced nitrogen IR2(the amount of nitrogen applied of early rice was 86.4 kg·hm-2, the density was 360000 holes·hm-2; the amount of nitrogen applied of late rice was 108 kg·hm-2, the density was 320000 holes·hm-2), respectively. IR2 of early rice had the lowest N2O cumulative emission, being 33.7% lower than CK. IR1(the amount of nitrogen applied of early rice was 103.2 kg·hm-2, the density was 320000 holes·hm-2; the amount of nitrogen applied of late rice was 129 kg·hm-2, the density was 280000 holes·hm-2) of late rice had the lowest N2O cumulative emission, being decreased by 94.9%. IR2 had the lowest annual total GWP and GHGI of double-season paddy fields. Compared with other treatments of increased density and reduced nitrogen, the IR2 treatment, where nitrogen fertilizer in both early and late rice was reduced by 28.0%, the density of early rice was increased by 28.6%, and the density of late rice was increased by 33.3%, was an effective and safe option for simultaneously ensuring high yield and reducing greenhouse gas emissions.


Greenhouse Gases , Oryza , Agriculture , China , Fertilizers/analysis , Greenhouse Gases/analysis , Methane/analysis , Nitrogen/analysis , Nitrous Oxide/analysis , Seasons , Soil , Water
13.
Chemosphere ; 227: 389-400, 2019 Jul.
Article En | MEDLINE | ID: mdl-31003123

Polychlorinated biphenyls (PCBs), a kind of persistent organic pollutant, can induce hepatotoxicity in mammals. However, PCB-induced hepatotoxicity in offspring and the underlying mechanisms have been rarely studied. In the present study, Wistar rats were administered with corn oil or PCB52 (1 mg/kg body weight/day, by gavage) from gestational day 7 to postnatal day 21. In the PCB52-treated group, birth body lengths and weights were significantly decreased compared with the control group, suggesting developmental toxicity. Cytoplasmic injury in hepatocytes was observed in PCB52-treated male offspring, while no pathologic change was observed in female offspring, suggesting sex-biased hepatotoxicity. Furthermore, using an RNA-Seq method, coincided with the sexual bias, 454 differential expression genes (DEGs) were screened out in liver tissues of PCB52-treated male offspring, while 10 DEGs were screened out in female offspring. By KEGG annotation analysis, 4 in 12 significant pathways in male offspring were metabolism-related. In the present study, together with cytoplasmic injury of hepatocytes, decreased metabolic enzymes both at RNA and protein levels might aggravate loss of clearance capacity of hepatocytes and induce hepatotoxicity. Moreover, over-expressed peroxisome proliferator-activated receptor delta and mitogen-activated protein kinase 9 might activate apoptosis, which was verified by the augments of cleaved poly ADP-ribose polymerase 1 and caspase 3 in PCB52-treated male offspring. Taken together, PCB52 had developmental toxicity and induced sex-biased hepatotoxicity. The hepatotoxicity in male offspring might be attributed to the aggravated loss of clearance capacity and activation of apoptosis.


Environmental Pollutants/toxicity , Polychlorinated Biphenyls/toxicity , Animals , Apoptosis/drug effects , Caspase 3 , Chemical and Drug Induced Liver Injury , Female , Hepatocytes/drug effects , Kinetics , Male , Poly (ADP-Ribose) Polymerase-1 , Rats , Rats, Wistar , Sex Factors , Toxicity Tests
14.
Front Neurosci ; 12: 802, 2018.
Article En | MEDLINE | ID: mdl-30450033

Abuse of methamphetamine (METH) results in neurological and psychiatric abnormalities. Lactulose is a poorly absorbed derivative of lactose and can effectively alleviate METH-induced neurotoxicity in rats. The present study was designed to investigate the effects of lactulose on METH-induced neurotoxicity. Rats received METH (15 mg/kg, 8 intraperitoneal injections, 12-h interval) or saline and received lactulose (5.3 g/kg, oral gavage, 12-h interval) or vehicle 2 days prior to the METH administration. Reactive oxygen species (ROS) and malondialdehyde (MDA) were measured. Protein levels of toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor associated factor 6 (TRAF6), nuclear factor κB (NFκB), interleukin (IL)-1ß, IL-6, TNF-α, cleaved caspase 3, and poly(ADP-ribose) polymerase-1 (PARP-1) were determined by western blotting. mRNA expressions of nuclear factor erythroid 2-relatted factor-2 (Nrf2), p62, and heme oxygenase-1 (HO-1) were assessed by RT-qPCR. The lactulose pretreatment decreased METH-induced cytoplasmic damage in rat livers according to histopathological observation. Compared to the control group, overproduction of ROS and MDA were observed in rat striatums in the METH alone-treated group, while the lactulose pretreatment significantly attenuated the METH-induced up-regulation of oxidative stress. The lactulose pretreatment significantly repressed over-expressions of proteins of TLR4, MyD88, TRAF6, NFκB, IL-1ß, IL-6, TNF-α, cleaved caspase 3, PARP-1. The lactulose pretreatment increased mRNA expressions of Nrf2, p62, and HO-1. These findings suggest that lactulose pretreatment can alleviate METH-induced neurotoxicity through suppressing neuroinflammation and oxidative stress, which might be attributed to the activation of the Nrf2/HO-1 axis.

15.
Plant Physiol ; 178(1): 283-294, 2018 09.
Article En | MEDLINE | ID: mdl-30018171

Sporopollenin is the major component of the outer pollen wall (sexine). It is synthesized using a pathway of approximately eight genes in Arabidopsis (Arabidopsis thaliana). MALE STERILITY188 (MS188) and its direct upstream regulator ABORTED MICROSPORES (AMS) are two transcription factors essential for tapetum development. Here, we show that all the sporopollenin biosynthesis proteins are specifically expressed in the tapetum and are secreted into anther locules. MS188, a MYB transcription factor expressed in the tapetum, directly regulates the expression of POLYKETIDE SYNTHASE A (PKSA), PKSB, MALE STERILE2 (MS2), and a CYTOCHROME P450 gene (CYP703A2). By contrast, the expression of CYP704B1, ACYL-COA SYNTHETASE5 (ACOS5), TETRAKETIDE a-PYRONE REDUCTASE1 (TKPR1) and TKPR2 are significantly reduced in ams mutants but not affected in ms188 mutants. However, MS188 but not AMS can activate the expression of CYP704B1, ACOS5, and TKPR1 In ms188, dominant suppression of MS188 homologs reduced the expression of these genes, suggesting that MS188 and other MYB family members play redundant roles in activating their expression. The expression of some sporopollenin synthesis genes (PKSA, PKSB, TKPR2, CYP704B1, and ACOS5) was rescued when MS188 was expressed in ams Therefore, MS188 is a key regulator for activation of sporopollenin synthesis, and AMS and MS188 may form a feed-forward loop that activates the expression of the sporopollenin biosynthesis pathway for rapid pollen wall formation.


Biopolymers/biosynthesis , Carotenoids/biosynthesis , Cell Wall/genetics , Gene Expression Profiling , Gene Expression Regulation, Plant , Pollen/genetics , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cell Wall/metabolism , Coenzyme A Ligases/genetics , Coenzyme A Ligases/metabolism , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Microscopy, Confocal , Mutation , Plants, Genetically Modified , Pollen/cytology , Pollen/metabolism , Polyketide Synthases/genetics , Polyketide Synthases/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
16.
Toxicol Lett ; 289: 107-113, 2018 Jun 01.
Article En | MEDLINE | ID: mdl-29550550

Methamphetamine (METH) is a widely abused psychostimulant. Lactulose is a non-absorbable sugar, which effectively decreases METH-induced neurotoxicity in rat. However, the exact mechanisms need further investigation. In this study, 5-week-old male Sprague Dawley rats received METH (15 mg/kg, 8 intraperitoneal injections, 12-h interval) or saline and received lactulose (5.3 g/kg, oral gavage, 12-h interval) or vehicle 2 days prior to the METH administration. Compared to the control group, in the METH alone group, cytoplasmic vacuolar degeneration in hepatocytes, higher levels of alanine transaminase, aspartate transaminase and ammonia, overproduction of reactive oxygen species (ROS) and increase of superoxide dismutase activity in the blood were observed. Moreover, in rat striatum, expressions of nuclear factor erythroid 2-relatted factor-2 (Nrf2) and heme oxygenase-1 were suppressed in the nucleus, although over-expression of Nrf2 were observed in cytoplasm. Over-expressions of BECN1 and LC3-II indicated initiation of autophagy, while overproduction of p62 might suggest deficient autophagic vesicle turnover and impaired autophagy. Furthermore, accumulation of p62 cloud interact with Keap1 and then aggravate cytoplasmic accumulation of Nrf2. Consistently, over-expressions of cleaved caspase 3 and poly(ADP-ribose) polymerase-1 suggested the activation of apoptosis. The pretreatment with lactulose significantly decreased rat hepatic injury, suppressed hyperammonemia and ROS generation, alleviated the impaired autophagy in striatum, rescued the antioxidant system and repressed apoptosis. Taken together, with decreased blood ammonia, lactulose pretreatment reduced METH-induced neurotoxicity through alleviating the impaired autophagy, stabilizing the perturbed antioxidant system and suppressing apoptosis in rat striatum.


Apoptosis/drug effects , Autophagy/drug effects , Corpus Striatum/drug effects , Lactulose/therapeutic use , Neuroprotective Agents/therapeutic use , Neurotoxicity Syndromes/prevention & control , Oxidative Stress/drug effects , Animals , Antioxidants/therapeutic use , Biomarkers/metabolism , Central Nervous System Stimulants/toxicity , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/pathology , Chemical and Drug Induced Liver Injury/prevention & control , Corpus Striatum/metabolism , Corpus Striatum/pathology , Liver/drug effects , Liver/metabolism , Liver/pathology , Male , Methamphetamine/toxicity , Nerve Tissue Proteins/metabolism , Neurons/drug effects , Neurons/metabolism , Neurons/pathology , Neurotoxicity Syndromes/metabolism , Neurotoxicity Syndromes/pathology , Random Allocation , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism
17.
Toxicol Lett ; 289: 28-41, 2018 Jun 01.
Article En | MEDLINE | ID: mdl-29518472

Hepatotoxicity is one of the adverse health effects induced by polychlorinated biphenyls (PCBs). Recently, autophagy was revealed to play an important role in PCBs-induced toxicology, however, its precise role in PCBs-induced hepatotoxicity is as yet unknown. In this study, treatment of PCB28/PCB52 for 48 h dose-dependently induced hepatotoxicity at doses of 10, 20, 40 and 80 µM in homo and rattus hepatocytes. Expressions of proteins of BECN1, LC3-II and ULK1 significantly increased in PCB28/PCB52-treated cells at a dose of 40 µM, implying initiation of autophagy. Over-expression of p62 suggested deficient clearance of autophagosome. Consistently, accumulation of autophagosome was observed by transmission-electron microscopy and confocal fluorescence microscopy using adenovirus expressing mRFP-GFP-LC3, which may initiate apoptosis. Furthermore, increased reactive oxygen species levels might also induce autophagy and apoptosis. Consistently, cell apoptosis was evoked by the treatment of PCB28/PCB52 compared to the respective controls, which coincided with obvious hepatotoxicity. Subsequently, an inhibitor (3-methlyadenine) and an initiator (rapamycin) of autophagy were used. Compared to PCB28/PCB52 alone-treated cells, initiation of autophagy, blocked autophagic flux, cell apoptosis and hepatotoxicity were alleviated by 3-methlyadenine and aggravated by rapamycin, respectively. Taken together, PCB28 and PCB52 induced hepatotoxicity by impairing autophagic flux and stimulating cell apoptosis in vitro.


Apoptosis/drug effects , Autophagy/drug effects , Environmental Pollutants/toxicity , Gene Expression Regulation/drug effects , Hepatocytes/drug effects , Polychlorinated Biphenyls/toxicity , Animals , Autophagosomes/drug effects , Autophagosomes/metabolism , Autophagosomes/ultrastructure , Cell Line , Cell Survival/drug effects , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Hepatocytes/metabolism , Hepatocytes/ultrastructure , Humans , Kinetics , Microscopy, Electron, Transmission , Microscopy, Fluorescence , Oxidative Stress/drug effects , Rats , Reactive Oxygen Species/agonists , Reactive Oxygen Species/metabolism , Recombinant Fusion Proteins/metabolism
18.
Appl Nurs Res ; 27(4): 258-60, 2014 Nov.
Article En | MEDLINE | ID: mdl-24849067

An effective working relationship between physicians and nurses is enhanced by fostering positive perceptions and collaborative attitudes between the two professions. This brief paper examines the effect of an interprofessional simulation-based communication education program in enhancing medical and nursing students' perceptions of each other's profession and their attitudes toward nurse-physician collaboration. Pretest-Posttest design was conducted on 96 medical and nursing students who demonstrated the existence of professional stereotypes in the baseline data. This study showed that by promoting open communication, shared information and decision-making, mutual respect, and trust during the interprofessional simulation training, a positive transformation on the stereotypes and attitudes toward nurse-physician collaboration can be achieved.


Attitude of Health Personnel , Inservice Training/organization & administration , Interprofessional Relations , Physician-Nurse Relations , Stereotyped Behavior , Humans
19.
Nurse Educ Today ; 34(2): 259-64, 2014 Feb.
Article En | MEDLINE | ID: mdl-23518067

BACKGROUND: Communication and teamwork between doctors and nurses are critical for optimal patient care. Simulation and interprofessional team learning are emerging as significant learning strategies to promote teamwork and communication between different health professionals. AIM: The aim of the study is to describe the development, implementation and evaluation of a simulation-based interprofessional educational (Sim-IPE) program, using a presage-process-product (3P) model, for improving medical and nursing students' communication skills in caring of a patient with physiological deterioration. METHOD: The program was conducted using full-scale simulation and communication strategies adapted from Team Strategies and Tools to Enhance Performance and Patient Safety (TeamSTEPPS). 127 medical and nursing students participated in a 3-hour small group interprofessional learning that incorporated simulation scenarios of deteriorating patients. Pre and post-tests were conducted to assess the students' self-confidence in interprofessional communication and perception in interprofessional learning. After the training, the students completed a satisfaction questionnaire. RESULTS: Both medicine and nursing groups demonstrated a significant improvement on post-test score from pre-test score for self-confidence (p<.0001) and perception (p<.0001) with no significant differences detected between the two groups. The participants were highly satisfied with their simulation learning. CONCLUSION: The Sim-IPE has better prepared the medical and nursing students in communicating with one another in providing safe care for deteriorating patient. In addition, it has improved their perception towards interprofessional learning. This pre-registration interprofessional education could prepare them for more comprehensive interprofessional team learning at post-registration level.


Communication , Interprofessional Relations , Patient Safety , Patient Simulation , Attitude of Health Personnel , Critical Illness , Female , Humans , Male , Patient Care Team , Singapore , Students, Nursing , Surveys and Questionnaires , Young Adult
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