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Pre-rheumatoid arthritis （Pre-RA） is the asymptomatic state of rheumatoid arthritis （RA）， and its progression showed complexity， dynamics and significant individual differences. The dynamic prediction model is valuable in identifying individual risks and taking timely preventive and control measures. It is believed that applying the dynamic prediction model to traditional Chinese medicine （TCM） clinical studies of Pre-RA is expected to predict the critical state of Pre-RA to RA， reveal the evolution of Pre-RA， reflect the external authenticity of the TCM clinical studies， and complement the clinical efficacy evaluation method. Accordingly， it is envisioned to construct a dynamic prediction model for Pre-RA progression based on TCM clinical trial data through the dynamic prediction model algorithm， and to apply long-term follow-up cohort data for external validation， thereby providing a basis for scientific warning and clinical decision-making on the evolution of Pre-RA.
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Objective To simulate the possible systematic delivery errors introduced by monitor units ( MU) and multi-leaf collimator ( MLC) in radiotherapy plans for nasopharyngeal carcinoma ( NPC) , and to analyze the dosimetric sensitivity of static intensity-modulated radiotherapy ( IMRT ) and volumetric modulated arc therapy ( VMAT) with these errors. Methods Five IMRT plans were replanned using VMAT modality with the same physical parameters, and then MU errors of 125%, 250%, and 5. 00% were introduced into IMRT and VMAT plans. Meanwhile, to simulate leaf position errors during delivery, MLC position errors (025 mm, 050 mm, 100 mm, 150 mm, and 200 mm) were introduced by modifying the original plan documents. The types of MLC errors were as follows:( 1) the MLC banks moved in the same direction;( 2) the MLC banks moved in opposing directions ( expand or contract the MLC gaps ) . The differences in dosimetric sensitivity introduced by MU and MLC errors between IMRT and VMAT plans for NPC were calculated by linear regression analysis. Results With the increase in MU errors, the doses to target and organs at risk ( OARs) of IMRT and VMAT plans increased in a linear way, and met R2=0992-1000( P<005) . For MLC errors, the average dosimetric sensitivity for target and OARs of IMRT and VMAT were-026%/mm and-065%/mm in case of offset errors, 487%/mm and 868%/mm in case of expansion errors, and -604%/mm and -988%/mm in case of indentation errors. In addition, the dosimetric sensitivity with the three types of MLC errors was greater for VMAT plan than for IMRT plan. ConclusionsMU and MLC errors have a significant effect on the dose distribution of IMRT, and particularly VMAT, for NPC. It is important to execute routine quality assurance of MLC to ensure accurate radiotherapy.
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Objective To simulate the possible systematic delivery errors introduced by monitor units ( MU) and multi-leaf collimator ( MLC) in radiotherapy plans for nasopharyngeal carcinoma ( NPC) , and to analyze the dosimetric sensitivity of static intensity-modulated radiotherapy ( IMRT ) and volumetric modulated arc therapy ( VMAT) with these errors. Methods Five IMRT plans were replanned using VMAT modality with the same physical parameters, and then MU errors of 125%, 250%, and 5. 00% were introduced into IMRT and VMAT plans. Meanwhile, to simulate leaf position errors during delivery, MLC position errors (025 mm, 050 mm, 100 mm, 150 mm, and 200 mm) were introduced by modifying the original plan documents. The types of MLC errors were as follows:( 1) the MLC banks moved in the same direction;( 2) the MLC banks moved in opposing directions ( expand or contract the MLC gaps ) . The differences in dosimetric sensitivity introduced by MU and MLC errors between IMRT and VMAT plans for NPC were calculated by linear regression analysis. Results With the increase in MU errors, the doses to target and organs at risk ( OARs) of IMRT and VMAT plans increased in a linear way, and met R2=0992-1000( P<005) . For MLC errors, the average dosimetric sensitivity for target and OARs of IMRT and VMAT were-026%/mm and-065%/mm in case of offset errors, 487%/mm and 868%/mm in case of expansion errors, and -604%/mm and -988%/mm in case of indentation errors. In addition, the dosimetric sensitivity with the three types of MLC errors was greater for VMAT plan than for IMRT plan. ConclusionsMU and MLC errors have a significant effect on the dose distribution of IMRT, and particularly VMAT, for NPC. It is important to execute routine quality assurance of MLC to ensure accurate radiotherapy.
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Objective To compare the dosimetric difference among plans designed by 4-field,6-field TomoDirect and TomoHelical techniques in Tomotherapy system for left-breast cancer patients with radiotherapy after breast-conserving surgery.Method A total of 16 patients with left-breast cancer following breast-conserving surgery and intensity-modulated radiation therapy were enrolled in this retrospective study.The 4-field TomoDirect (TD4),6-field TomoDirect (TD6),and TomoHelical (TH) techniques were applied to design simulation plans in tomotherapy system for each patient,respectively.The differences of dose distribution and treatment parameters were analyzed in this study.Results Three plans all met the clinical requirement.Thereinto,TD4 was superior to TH in the dose limitation of organs at risk (OARs),especially the max dose of cord and right-breast,thc 5 Gy radiation volume of lung,and the mean dose of heart(F =595.60,129.24,60.44,65.37,P ＜ 0.05),but inferior to TH in dose homogeneity (HI) and conformity (CI) (F =2.78,60.93,P ＜ 0.05).However,TD6 improved TD4's HI and CI when delivered the lower OARs dose compared to TH.Meanwhile,the number of monitor units was less in TD technique and reduced the treatment times (F =24.89,3.75,P ＜ O.05).Conclusions For the radiotherapy of left-breast cancer patients after breast-conserving surgery,TD6 technique appeared to be superior,with the lower radiation dose of OARs compared to TH technique,and the better target's HI and CI in comparison with TD4 technique,especially in patients with early stage breast cancer.
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To investigate the effect of crocin on the progression and generalized seizure of temporal lobe epilepsy in mice.Hippocampus rapid kindling model was established in C57BL/6J mice. The effects of crocin on seizure stage, afterdischarge duration (ADD), number of stimulation in each stage and final state, the incidence of generalized seizure (GS), average seizure stage and ADD were observed.Crocin (20 mg/kg) significantly retarded behavioral seizure stages (<0.05) and shortened cumulative ADD (<0.01) during hippocampus rapid kindling acquisition in mice compared with vehicle group. Meanwhile, number of stimulations in stage 1-2 was significantly increased (<0.05) and the incidence of fully kindled animals was significantly decreased (<0.01). However, 10 or 50 mg/kg crocin showed no significant effect on the above indexes (all>0.05). Crocin (100 or 200 mg/kg) significantly decreased the incidence of GS (all<0.01) and reduced average seizure stages (all<0.01) in fully-kindled mice compared with vehicle group; Fifty mg/kg crocin only reduced average seizure stages (<0.05).Low-dose crocin can retard the progression in hippocampus rapid kindling acquisition in mice, while high-dose crocin relieves the GS in fully-kindled mice, which suggests that crocin may be a potential anti-epileptic compound.
Subject(s)
Animals , Mice , Anticonvulsants , Pharmacology , Carotenoids , Pharmacology , Therapeutic Uses , Dose-Response Relationship, Drug , Electric Stimulation , Epilepsy, Temporal Lobe , Drug Therapy , Hippocampus , Kindling, Neurologic , Physiology , Mice, Inbred C57BL , Seizures , Classification , Drug TherapyABSTRACT
AIM: To analyze and compare the changes of pressure phase plane(PPP) derived τ and K on isolated rat heart during ischemia/reperfusion, and to explore the value of PPP derived τ and K for evaluation of left ventricular diastolic dysfunction. METHODS: LVEDP, -d(p/dt)_(max), τ and K were measured and calculated during ischemia/reperfusion in Sprague-Dawley rat hearts. Meanwhile, the level of lactate dehydrogenase (LDH) in the coronary effluent was measured, and the ultrastructure changes in myocardium were observed under electron microscope. RESULTS: Compared with control group, τ increased and K reduced significantly in each ischemic group in a time dependent manner (P<0.05). With prolonged ischemia, τ was even higher and K was even lower (P<0.05). Compared with control group, except ischemia 15 min, LDH in other groups increased significantly at 10 min and 20 min after reperfusion (P<0.05). Compared with ischemia 30 min, LDH of ischemia 45 min and ischemia 60 min were even higher at 10 min and 20 min after reperfusion (P<0.05). With prolonged ischemia, the abnormal changes of the myocardial ultrastructure were observed. CONCLUSION: PPP derived τ and K may be promising indexes for quantitative assessment of left ventricular diastolic function on isolated) rat heart during ischemia/reperfusion, and indication of the severity of ischemia/reperfusion injury.
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The methods for evaluating left ventricular diastolic function completely and simply are lacking in our country at present. To solve this problem, we presents in this paper a novel method, which is developed according to certain algorithms and mathematic models and is carried out by a MATLAB program. This method mainly obtains dP/dt loops, and calculates four important indices, including left ventricular end-diastolic pressure (LVEDP), Maximal decrease in velocity of left ventricular pressure (--(dP/dt)max), Time constant of ventricular isovolumic relaxation (tau) and Chamber stiffness (Kd), according to the changes of left ventricular pressure. The results obtained from the experiment of isolated rat hearts during ischemia/reperfusion have demonstrated the usefulness and validity of this method. Therefore, with the use of tau and Kd as indicators, this is a sensitive and effective method for evaluating the left ventricular diastolic function, and it can be applied to early detection of left ventricular diastolic dysfunction.
Subject(s)
Animals , Humans , Male , Rats , Algorithms , Blood Pressure , Diastole , In Vitro Techniques , Models, Cardiovascular , Rats, Sprague-Dawley , Reperfusion Injury , Ventricular Dysfunction, Left , Diagnosis , Ventricular Function, Left , PhysiologyABSTRACT
Objective To observe the elimination of oxygen free radicals in rat myocardium mitochondria by diazoxide(DE) during different duration of hypothermic preservation.Methods The Langendorff model of isolated rat heart was used.After stored in 4℃ Celsior solution or Celsior solution containing 30 ?mol/L of DE for different duration(0,3,6,9 or 12h),the activity of the superoxide dismutase(SOD) and the content of maleic dialdehyde(MDA) in heart mitochondrial were measured.The myocardial mitochondria ultrastructure was also evaluated.Results(1) After hypothermic preservation,the activity of SOD was decreased,the content of MDA was increased.The ultrastructure of myocardium mitochondria was also destrored in preserved rat hearts in a time-dependent manner.(2) Compared with the corresponding Celsior solution hypothermic preservation groups,DE significantly improved the above indexes(SOD,MDA and myocardial mitochondria ultrastructure).Conclusion Diazoxide can protect rat myocardial mitochondria from long-term hypothermic preservation injury by direct elimination of oxygen free radials and enhancement of the activity of SOD.
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AIM:To confirm the action of the light transmission method in evaluating focal ischemic cerebral infarction on persistent focal cerebral ischemia in mice. METHODS:Persistent focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO). Bederson's neurological scores, climbing board and hanging test were performed 24 h after ischemia, and infarct volume, brain hemisphere area, neuron density of cortex and subcortex were measured with computer-assisted imaging. Pranlukast ( 0.1 mg?kg -1) or nimodipine ( 0.4 mg?kg -1) were injected ip once daily for 3 days and to 1 h before MCAO assess the neuroprotective effect. RESULTS:The infarct volumes measured by light transmission closely correlated with that measured by TTC staining and neuron densities. The infarct volumes measured by light transmission well correlated with the neurological scores measured by integrated graded approach, too. Both pranlukast and nimodipine significantly attenuated infarct volumes and the ratio of ischemic/non-ischemic hemispheres, and reduced neurological deficits and neuron death. CONCLUSION:Light transmission and integrated graded approach can be used not only for qualitative analysis of focal cerebral ischemia, but also for evaluating the neuroprotective effect of drugs.
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AIM:To investigate the effect of high glucose on the expression of an endoplasmic reticulum stress marker glucose-regulated protein 78(GRP78),and explore its underlying mechanism.METHODS:(1) Human umbilical vein endothelial cells(HUVECs) were exposed to normal glucose(5.5 mmol/L) and high glucose(30 mmol/L) for 24 h,36 h or 48 h.Cell viability was determined by MTT method.Cell apoptosis was detected by flow cytometry analysis.The expression of proteins was evaluated by Western blotting analysis.RESULTS:After treated with high glucose for 24-48 h,the expression of GRP78 increased early but decreased at 48 h of incubation,while cyclooxygenase-2(COX-2) expression increased in a time-dependent manner.COX-2 selective inhibitor nimesulide inhibited high glucose induced changes of GRP78 expression and also inhibited high glucose induced cell apoptosis.CONCLUSION:Prolonged high glucose exposure changes the expression of GRP78 in a COX-2 dependent manner in HUVECs.