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1.
Farshad Abedi Bibi Marjan Razavi Hossein Hosseinzadeh 《Phytotherapy research : PTR》2020,34(4):729-741
Beneficial therapeutic effects of phenolic acids have been proven in various research projects including in vivo and in vitro studies. Gentisic acid (GA) is a phenolic acid that has been associated with useful effects on human health, such as antiinflammatory, antigenotoxic, hepatoprotective, neuroprotective, antimicrobial, and especially antioxidant activities. It is an important metabolite of aspirin and also widely distributed in plants as a secondary plant product such as Gentiana spp., Citrus spp., Vitis vinifera, Pterocarpus santalinus, Helianthus tuberosus, Hibiscus rosa‐sinensis, Olea europaea, and Sesamum indicum and in fruits such as avocados, batoko plum, kiwi fruits, apple, bitter melon, black berries, pears, and some mushrooms. This study was undertaken to review the pharmacological effects, pharmacokinetic properties as well as toxicity and pharmaceutical applications of GA. 相似文献
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Hussein Abbouchie Michael Chao Mark Tacey Daryl Lim Joon Huong Ho Mario Guerrieri Michael Ng Farshad Foroudi 《Journal of Medical Imaging and Radiation Oncology》2020,64(2):293-302
Stereotactic body radiotherapy has emerged as one of the preferred treatments for patients with spine metastases, with the potential for long‐term control from lesion irradiation. Post‐treatment vertebral compression fractures are a known complication of this therapy, contributing to worsening pain and reduced quality of life, sometimes requiring surgical intervention. This review explores the current knowledge of post‐radiotherapy fractures, in terms of the rates and associated predictive factors. A search of databases including Medline, Embase and the Cochrane Library was conducted using keywords such as ‘vertebral compression fracture’, ‘stereotactic body radiotherapy’ and ‘spine metastases’. The search was limited to published studies up to March 2019, reporting clinical outcomes including both the post‐treatment fracture rate and statistical identification of associated risk factors. Rates of post‐treatment fractures ranged from 4 to 39%. A variety of factors were found to increase the risk, including the appearance of lytic vertebral disease, degree of pre‐existing compression, spinal malalignment, increased dose per fraction and a Spinal Instability Neoplastic Score >6. This knowledge can enable clinicians to counsel patients when considering management options for spine metastases, maintaining the balance between local tumour control and the risk of subsequent fracture. 相似文献
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Shahrzad Ghafary Roshanak Ghobadian Mohammad Mahdavi Hamid Nadri Alireza Moradi Tahmineh Akbarzadeh Zahra Najafi Mohammad Sharifzadeh Najmeh Edraki Farshad Homayouni Moghadam Mohsen Amini 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2020,28(2):463
BackgroundAcetylcholine deficiencies in hippocampus and cortex, aggregation of β-amyloid, and β-secretase over activity have been introduced as main reasons in pathogenesis of Alzheimer’s disease.MethodsColorimetric Ellman’s method was used for determination of IC50 value in AChE and BChE inhibitory activity. The kinetic studies, neuroprotective and β-secretase inhibitory activities, evaluation of inhibitory potency on β-amyloid (Aβ) aggregations induced by AChE, and docking study were performed for prediction of the mechanism of action.Result and discussionA new series of cinnamic acids-tryptamine hybrid was designed, synthesized, and evaluated as dual cholinesterase inhibitors. These compounds demonstrated in-vitro inhibitory activities against acetyl cholinesterase (AChE) and butyryl cholinesterase (BChE). Among of these synthesized compounds, (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(3,4-dimethoxyphenyl)acrylamide (5q) demonstrated the most potent AChE inhibitory activity (IC50 = 11.51 μM) and (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(2-chlorophenyl)acrylamide (5b) were the best anti-BChE (IC50 = 1.95 μM) compounds. In addition, the molecular modeling and kinetic studies depicted 5q and 5b were mixed type inhibitor and bound with both the peripheral anionic site (PAS) and catalytic sites (CAS) of AChE and BChE. Moreover, compound 5q showed mild neuroprotective in PC12 cell line and weak β-secretase inhibitory activities. This compound also inhibited aggregation of β-amyloid (Aβ) in self-induced peptide aggregation test at concentration of 10 μM.ConclusionIt is worth noting that both the kinetic study and the molecular modeling of 5q and 5b depicted that these compounds simultaneously interacted with both the catalytic active site and the peripheral anionic site of AChE and BChE. These findings match with those resulted data from the enzyme inhibition assay. Graphical abstractOpen in a separate windowA new series of cinnamic-derived acids-tryptamine hybrid derivatives were designed, synthesized and evaluated as butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) inhibitors and neuroprotective agents. Compound 5b and 5q, as the more potent compounds, interacted with both the peripheral site and the choline binding site having mixed type inhibition. Results suggested that derivatives have a therapeutic potential for the treatment of AD.Electronic supplementary materialThe online version of this article (10.1007/s40199-020-00346-9) contains supplementary material, which is available to authorized users. 相似文献
6.
Nadja A. Farshad-Amacker Brett Lurie Richard J. Herzog Mazda Farshad 《The spine journal》2014,14(8):1470-1475
Background contextDifferent types of lumbosacral transitional vertebra (LSTV) are classified based on the relationship of the transverse process of the last lumbar vertebra to the sacrum. The Ferguson view (30° angled anteroposterior [AP] radiograph) is supposed to have a sufficient interreader reliability in classification of LSTV, but is not routinely available. Standard AP radiographs and magnetic resonance imaging (MRI) are often available, but their reliability in detection and classification of LSTV is unknown.PurposeThe purpose of this study was to evaluate the interreader reliability of detection and classification of LSTV with standard AP radiographs and report its accuracy by use of intermodality statistics compared with MRI as the gold standard.Study design/settingRetrospective case control study.Patient sampleA total of 155 subjects (93 cases: LSTV type 2 or higher; 62 controls).Outcome measuresInterreader reliability in detection and classification of LSTV using standard AP radiographs and coronal MRI as well as accuracy of radiographs compared with MRI.MethodsAfter institutional review board approval, coronal MRI scans and conventional AP radiographs of 155 subjects (93 LSTV type 2 or higher and 62 controls) were retrospectively reviewed by two independent, blinded readers and classified according to the Castellvi classification. Interreader reliability was assessed using kappa statistics for detection of an LSTV and identification of all subtypes (six variants; 1: no LSTV or type I, 2: LSTV type 2a, 3: LSTV type 2b, 4: LSTV type 3a, 5: LSTV type 3b, 6: LSTV type 4) for MRI scans and standard AP radiographs. Further, accuracy and positive and negative predictive values were calculated for standard AP radiographs to detect and classify LSTV using MRI as the gold standard.ResultsThe interreader reliability was at most moderate for the detection (k=0.53) and fair for classification (wk=0.39) of LSTV in standard AP radiograph. However, the interreader reliability was very good for detection (k=0.93) and classification (wk=0.83) of LSTV in MRI. The accuracy and positive and negative predictive values of standard AP radiograph were 76% to 84%, 72% to 86%, and 79% to 81% for the detection and 53% to 58%, 51% to 76%, and 49% to 55% for the classification of LSTV, respectively.ConclusionStandard AP radiographs are insufficient to detect or classify LSTV. Coronal MRI scans, however, are highly reliable for classification of LSTV. 相似文献
7.
Mazda Farshad Nadja A. Farshad-Amacker Elias Bachmann Jess G. Snedeker Samuel L. Schmid 《Acta neurochirurgica》2014,156(11):2147-2151
Background
While convergent placement of pedicle screws in the axial plane is known to be more advantageous biomechanically, surgeons intuitively aim toward a parallel placement of screws in the sagittal plane. It is however not clear whether parallel placement of screws in the sagittal plane is biomechanically superior to a non-parallel construct. The hypothesis of this study is that sagittal non-parallel pedicle screws do not have an inferior initial pull-out strength compared to parallel placed screws.Methods
The established lumbar calf spine model was used for determination of pull-out strength in parallel and non-parallel intersegmental pedicle screw constructs. Each of six lumbar calf spines (L1-L6) was divided into three levels: L1/L2, L3/L4 and L5/L6. Each segment was randomly instrumented with pedicle screws (6/45 mm) with either the standard technique of sagittal parallel or non-parallel screw placement, respectively, under fluoroscopic control. CT was used to verify the intrapedicular positioning of all screws. The maximum pull-out forces and type of failure were registered and compared between the groups.Results
The pull-out forces were 5,394 N (range 4,221 N to 8,342 N) for the sagittal non-parallel screws and 5,263 N (range 3,589 N to 7,554 N) for the sagittal-parallel screws (p?=?0.838). Interlevel comparisons also showed no statistically significant differences between the groups with no relevant difference in failure mode.Conclusion
Non-parallel pedicle screws in the sagittal plane have at least equal initial fixation strength compared to parallel pedicle screws in the setting of the here performed cadaveric calf spine experiments. 相似文献8.
Background Context
Nerve root compression causing symptomatic radiculopathy can occur within the intervertebral foramen. Sagittal magnetic resonance imaging (MRI) sequences are reliable in detection of nerve root contact to intraforaminal disc material, but a clinically relevant classification of degree of contact is lacking.Purpose
This study aimed to investigate a potential relation of amount of contact between intraforaminal disc material and nerve root to clinical findings and response after periradicular corticosteroid infiltration.Study Design
A post hoc analysis of a prospective cohort was carried out.Patient Sample
Patients who underwent computed tomography (CT)-guided periradicular corticosteroid infiltration (L1–L5) at our institution (January 2014 to May 2016) were included.Outcome Measures
The medical records and radiographic imaging were reviewed.Methods
T2-weighted MRI of the lumbar spine of patients with single-level symptomatic radiculopathy with (responders, n=28) or without (non-responders, n=14) pain relief after periradicular infiltration with corticosteroids were measured and compared by two independent readers to determine the amount of intraforaminal nerve root contact with the intervertebral disc (“melting” of the T2-hypointense signal). Pain relief was defined with a pain level decrease of >50% on a visual analogue scale and lack of pain relief with a pain level decrease of <25%, respectively. The amount of T2-hypointensity melting of disc and nerve root was categorized to 0%, 1%–25%, and over 25%.Results
Reader one identified 0% T2-melting in none of the responders, 1%–25% melting in 13 patients (46.4%), 26%–50% in 15 of the 28 patients (53.6%) with pain relief after periradicular corticosteroid infiltration (responders), with a mean amount of T2-melting of 5.9±2.1?mm, whereas the non-responder group had 0% T2-melting in 2 patients (14.3%), 1%–25% T2-melting in 11 patients (78.6%), and 26%–50% in 1 patient (7.1%), with a mean amount of T2-melting of 2.6±1.9?mm (p<.05).Reader two identified 0% T2-melting in none, 1%–25% T2-melting in 15 (53.6%) patients, and 26%–50% in 13 of the 28 responders (46.4%), with mean amount of 6.3±1.9?mm. In the non-responder group 0% T2-melting was seen in 3 patients (21.4%), 1%–25% T2-melting in 10 patients (71.4%), and 26%–50% in 1 patient (7.1%), with a mean amount of T2-melting of 2.7±1.9?mm (p<.05). None of the MRI showed T2-melting in over 50% of the circumference of the intraforaminal nerve root.A T2-melting of >25% had a high specificity of 93% but a sensitivity of 50%, thus a positive likelihood ratio of 7.5, to identify those with a pain relief of more than 50% after infiltration.Conclusion
The amount of T2-melting of disc material and nerve root on sagittal MRI (>25%) predicts the amount of pain relief by periradicular infiltration in patients with intraforaminal nerve root irritation. 相似文献9.
Jetan H. Badhiwala Christopher D. Witiw Farshad Nassiri Blessing N.R. Jaja Muhammad A. Akbar Alireza Mansouri Zamir Merali George M. Ibrahim Jefferson R. Wilson Michael G. Fehlings 《The spine journal》2018,18(12):2220-2231
Background Context
Predictors of outcome after surgery for degenerative cervical myelopathy (DCM) have been determined previously through hypothesis-driven multivariate statistical models that rely on a priori knowledge of potential confounders, exclude potentially important variables because of restrictions in model building, cannot include highly collinear variables in the same model, and ignore intrinsic correlations among variables.Purpose
The present study aimed to apply a data-driven approach to identify patient phenotypes that may predict outcomes after surgery for mild DCM.Study Design
This is a principal component analysis of data from two related prospective, multicenter cohort studies.Patient Sample
The study included patients with mild DCM, defined by a modified Japanese Orthopaedic Association score of 15–17, undergoing surgical decompression as part of the AOSpine CSM-NA or CSM-I trials.Outcome Measures
Patient outcomes were evaluated preoperatively at baseline and at 6 months, 1 year, and 2 years after surgery. Quality of life (QOL) was evaluated by the Neck Disability Index (NDI) and Short Form-36 version 2 (SF-36v2). These are both patient self-reported measures that evaluate health-related QOL, with NDI being specific to neck conditions and SF-36v2 being a generic instrument.Materials and Methods
The analysis included 154 patients. A heterogeneous correlation matrix was created using a combination of Pearson, polyserial, and polychoric regressions among 67 variables, which then underwent eigen decomposition. Scores of significant principal components (PCs) (with eigenvalues>1) were included in multivariate logistic regression analyses for three dichotomous outcomes of interest: achievement of the minimum clinically important difference [MCID] in (1) NDI (≤?7.5), (2) SF-36v2 Physical Component Summary (PCS) score (≥5), and (3) SF-36v2 Mental Component Summary (MCS) score (≥5).Results
Twenty-four significant PCs accounting for 75% of the variance in the data were identified. Two PCs were associated with achievement of the MCID in NDI. The first (PC 1) was dominated by variables related to surgical approach and number of operated levels; the second (PC 21) consisted of variables related to patient demographics, severity and etiology of DCM, comorbid status, and surgical approach. Both PC 1 and PC 21 also correlated with SF-36v2 PCS score, in addition to PC 4, which described patients' physical profile, including gender, height, and weight, as well as comorbid renal disease; PC 6, which received large loadings from variables related to cardiac disease, impaired mobility, and length of surgery and recovery; and PC 9, which harbored large contributions from features of upper limb dysfunction, cardiorespiratory disease, surgical approach, and region. In addition to PC 21, a component profiling patients' socioeconomic status and support systems and degree of physical disability (PC 24) was associated with achievement of the MCID in SF-36 MCS score.Conclusions
Through a data-driven approach, we identified several phenotypes associated with disability and physical and mental health-related QOL. Such data reduction methods may separate patient-, disease-, and treatment-related variables more accurately into clinically meaningful phenotypes that may inform patient care and recruitment into clinical trials. 相似文献10.
Zahra Aryan Negar Mahmoudi Ali Sheidaei Shahabeddin Rezaei Zohreh Mahmoudi Kimyia Gohari Nazila Rezaei Mohammad Javad Hajipour Arezou Dilmaghani-Marand Farideh Razi Mahdi Sabooni Farzad Kompani Alireza Delavari Bagher Larijani Farshad Farzadfar 《Journal of clinical lipidology》2018,12(6):1471-1481.e4