Showing 11075–11088 of 11,469 results for "Ghaeminejad Zeinab"

Journals 2019 EN

Antiepileptic Effects of a Novel Non-invasive Neuromodulation Treatment in a Subject With Early-Onset Epileptic Encephalopathy: Case Report With 20 Sessions of HD-tDCS Intervention

Oded Meiron · Rena Gale · Julia Namestnic +5 more

The current clinical investigation examined high-definition transcranial direct current stimulation (HD-tDCS) as a focal, non-invasive, anti-epileptic treatment in a child with early-onset epileptic encephalopathy. We investigated the clinical impact of repetitive (20 daily sessions) cathode-centered 4 × 1 HD-tDCS (1 mA, 20 min, 4 mm ring radius) over the dominant seizure-generating cortical zone in a 40-month-old child suffering from a severe neonatal epileptic syndrome known as Ohtahara syndrome (OS). Seizures and epileptiform activity were monitored and quantified using video-EEG over multiple days of baseline, intervention, and post-intervention periods. Primary outcome measures were changes in seizure frequency and duration on the last day of intervention versus the last baseline day, preceding the intervention. In particular, we examined changes in tonic spasms, tonic-myoclonic seizures (TM-S), and myoclonic seizures from baseline to post-intervention. A trend in TM-S frequency was observed indicating a reduction of 73% in TM-S frequency, which was non-significant [ t (4) = 2.05, p = 0.1], and denoted a clinically significant change. Myoclonic seizure (M-S) frequency was significantly reduced [ t (4) = 3.83, p = 0.019] by 68.42%, compared to baseline, and indicated a significant clinical change as well. A 73% decrease in interictal epileptic discharges (IEDs) frequency was also observed immediately after the intervention period, compared to IED frequency at 3 days prior to intervention. Post-intervention seizure-related peak delta desynchronization was reduced by 57%. Our findings represent a case-specific significant clinical response, reduction in IED, and change in seizure-related delta activity following the application of HD-tDCS. The clinical outcomes, as noted in the current study, encourage the further investigation of this focal, non-invasive neuromodulation procedure in other severe electroclinical syndromes (e.g., West syndrome) and in larger pediatric populations diagnosed with early-onset epileptic encephalopathy. Clinical Trial Registration: www.ClinicalTrials.gov , identifier NCT02960347, protocol ID: Meiron 2013-4.

Frontiers Media
Journals 2019 EN

Viability and Contractility of Rat Brain Pericytes in Conditions That Mimic Stroke; an in vitro Study

Mohammed Heyba · Lulwa A. A. D. Al-Abdullah · Andreas Henkel +3 more

Reopening of the cerebral artery after occlusion often results in “no-reflow” that has been attributed to the death and contraction ( rigor mortis ) of pericytes. Since this hypothesis still needs to be confirmed, we explored the effects of oxygen glucose deprivation (OGD) on viability and cell death of primary rat pericytes, in the presence or absence of neurovascular unit-derived cytokines. Two morphodynamic parameters, single cell membrane mobility (SCMM) and fractal dimension (D f ), were used to analyze the cell contractions and membrane complexity before and after OGD. We found a marginal reduction in cell viability after 2–6 h OGD; 24 h OGD caused a large reduction in viability and a large increase in the number of apoptotic and dead cells. Application of erythropoietin (EPO), or a combination of EPO and endothelial growth factor (VEGF A1−165 ) during OGD significantly reduced cell viability; application of Angiopoietin 1 (Ang1) during OGD caused a marginal, insignificant increase in cell viability. Simultaneous application of EPO, VEGF A1−165 , and Ang1 significantly increased cell viability during 24 h OGD. Twenty minutes and one hour OGD both significantly reduced SCMM compared to pre-OGD values, while no significant difference was seen in SCMM before and after 3 h OGD. There was a significant decrease in membrane complexity (D f ) at 20 min during the OGD that disappeared thereafter. In conclusion, OGD transiently affected cell mobility and shape, which was followed by apoptosis in cultured pericytes. Ang1 may have a potentiality for preventing from the OGD-induced apoptosis. Further studies could clarify the relationship between cell contraction and apoptosis during OGD.

Frontiers Media
Journals 2019 EN

Acute Cardiotoxicity With Concurrent Trastuzumab and Hypofractionated Radiation Therapy in Breast Cancer Patients

Mutlay Sayan · Zeinab Abou Yehia · Apar Gupta +3 more

Purpose: Radiotherapy for patients with non-metastatic human epidermal growth factor receptor 2 (HER2) positive breast cancer is commonly administered concurrently with adjuvant trastuzumab. However, there is limited data on the use of concurrent trastuzumab and hypofractionated radiotherapy (Hypo-RT), which is now standard of care for the majority of women receiving whole breast irradiation. In this study, we compared acute cardiotoxicity rates in HER2-positive breast cancer patients treated with concurrent trastuzumab and Hypo-RT or conventionally fractionated radiotherapy (Conv-RT). Methods: We performed a review of our institutional database to identify HER2-positive breast cancer patients treated with trastuzumab and Hypo-RT or Conv-RT from 2005 to 2018 who underwent serial cardiac Left Ventricular Ejection Fraction (LVEF) evaluation. Decrease in LVEF was assessed by either echocardiography (ECHO) or multiple gated acquisition (MUGA) scan performed at baseline and every 3 months during trastuzumab therapy. Significant LVEF decline was defined as an absolute decrease in LVEF of ≥10% below the lower limit of normal or ≥16% from baseline value. Results: We identified 41 patients treated with Hypo-RT and 100 patients treated with Conv-RT. Median follow-up was 32 months (range, 13–90 months). Baseline median LVEF was 62% (range, 50–81%) in Hypo-RT group and 64% (range, 51–76%) in Conv-RT group ( p = 0.893). Final median LVEF was 60% (range, 50–75%) in both groups. Three patients (7%) in Hypo-RT and five (5%) in Conv-RT group developed significant asymptomatic LVEF decline ( p = 0.203). There was no significant difference in mean heart dose in patients who developed significant asymptomatic LVEF decline vs. those who did not in Hypo-RT ( p = 0.427) and Conv-RT ( p = 0.354) groups. No symptomatic congestive heart failure was reported in either group. Conclusions: The rate of asymptomatic LVEF decline in patients receiving concurrent trastuzumab and Hypo-RT was low (7%) and was similar to the rate observed in patients receiving Conv-RT. Longer follow-up is warranted to assess late cardiotoxicity.

Frontiers Media
Journals 2019 EN

The Impact of Formal Mentorship Programs on Mentorship Experience Among Radiation Oncology Residents From the Northeast

Mutlay Sayan · Nisha Ohri · Anna Lee +8 more

Purpose: Strong mentorship has been shown to improve mentee productivity, clinical skills, medical knowledge, and career preparation. We conducted a survey to evaluate resident satisfaction with mentorship within their radiation oncology residency programs. Methods and Materials: In January 2019, 126 radiation oncology residents training at programs in the northeastern United States were asked to anonymously complete the validated Munich Evaluation of Mentoring Questionnaire (MEMeQ). Results of residents with a formal mentoring program were compared to those without a formal program. Results: Overall response rate was 42%( n = 53). Participants were 25% post-graduate year two (PGY-2), 21% PGY-3, 26% PGY-4, and 28% PGY-5. Only 38% of residents reported participation in a formal mentoring program, while 62% had no formal program, and 13% reported having no mentor at all. Residents participating in a formal mentoring program reported strikingly higher rates of overall satisfaction with mentoring compared to those who were not (90% vs. 9%, p < 0.001). Overall, 38% of residents were either satisfied/very satisfied with their mentoring experience, while 49% of residents were unsatisfied/very unsatisfied. Conclusion: Residents participating in a formal mentorship program are significantly more likely to be satisfied with their mentoring experience than those who are not. Our results suggest that radiation oncology residency programs should strongly consider implementing formal mentorship programs.

Frontiers Media
Journals 2019 EN

Phage Therapy with a Focus on the Human Microbiota

Sharita Divya Ganeshan · Zeinab Hosseinidoust

Bacteriophages are viruses that infect bacteria. After their discovery in the early 1900s, bacteriophages were a primary cure against infectious disease for almost 25 years, before being completely overshadowed by antibiotics. With the rise of antibiotic resistance, bacteriophages are being explored again for their antibacterial activity. One of the critical apprehensions regarding bacteriophage therapy, however, is the possibility of genome evolution, development of phage resistance, and subsequent perturbations to our microbiota. Through this review, we set out to explore the principles supporting the use of bacteriophages as a therapeutic agent, discuss the human gut microbiome in relation to the utilization of phage therapy, and the co-evolutionary arms race between host bacteria and phage in the context of the human microbiota.

Multidisciplinary Digital Publishing Institute
Journals 2019 EN

On the Neuroprotective Effects of Naringenin: Pharmacological Targets, Signaling Pathways, Molecular Mechanisms, and Clinical Perspective

Zeinab Nouri · Sajad Fakhri · Fardous F. ElSenduny +4 more

As a group of progressive, chronic, and disabling disorders, neurodegenerative diseases (NDs) affect millions of people worldwide, and are on the rise. NDs are known as the gradual loss of neurons; however, their pathophysiological mechanisms have not been precisely revealed. Due to the complex pathophysiological mechanisms behind the neurodegeneration, investigating effective and multi-target treatments has remained a clinical challenge. Besides, appropriate neuroprotective agents are still lacking, which raises the need for new therapeutic agents. In recent years, several reports have introduced naturally-derived compounds as promising alternative treatments for NDs. Among natural entities, flavonoids are multi-target alternatives affecting different pathogenesis mechanisms in neurodegeneration. Naringenin is a natural flavonoid possessing neuroprotective activities. Increasing evidence has attained special attention on the variety of therapeutic targets along with complex signaling pathways for naringenin, which suggest its possible therapeutic applications in several NDs. Here, in this review, the neuroprotective effects of naringenin, as well as its related pharmacological targets, signaling pathways, molecular mechanisms, and clinical perspective, are described. Moreover, the need to develop novel naringenin delivery systems is also discussed to solve its widespread pharmacokinetic limitation.

Multidisciplinary Digital Publishing Institute
Journals 2019 EN

Hydrolysis of Glycosyl Thioimidates by Glycoside Hydrolase Requires Remote Activation for Efficient Activity

Laure Guillotin · Zeinab Assaf · Salvatore G. Pistorio +3 more

Chemoenzymatic synthesis of glycosides relies on efficient glycosyl donor substrates able to react rapidly and efficiently, yet with increased stability towards chemical or enzymatic hydrolysis. In this context, glycosyl thioimidates have previously been used as efficient donors, in the case of hydrolysis or thioglycoligation. In both cases, the release of the thioimidoyl aglycone was remotely activated through a protonation driven by a carboxylic residue in the active site of the corresponding enzymes. A recombinant glucosidase (DtGly) from Dictyoglomus themophilum, previously used in biocatalysis, was also able to use such glycosyl thioimidates as substrates. Yet, enzymatic kinetic values analysis, coupled to mutagenesis and in silico modelling of DtGly/substrate complexes demonstrated that the release of the thioimidoyl moiety during catalysis is only driven by its leaving group ability, without the activation of a remote protonation. In the search of efficient glycosyl donors, glycosyl thioimidates are attractive and efficient. Their utility, however, is limited to enzymes able to promote leaving group release by remote activation.

Multidisciplinary Digital Publishing Institute
Journals 2019 EN

A Varied Density-based Clustering Approach for Event Detection from Heterogeneous Twitter Data

Zeinab Ghaemi · Mahdi Farnaghi

Extracting the latent knowledge from Twitter by applying spatial clustering on geotagged tweets provides the ability to discover events and their locations. DBSCAN (density-based spatial clustering of applications with noise), which has been widely used to retrieve events from geotagged tweets, cannot efficiently detect clusters when there is significant spatial heterogeneity in the dataset, as it is the case for Twitter data where the distribution of users, as well as the intensity of publishing tweets, varies over the study areas. This study proposes VDCT (Varied Density-based spatial Clustering for Twitter data) algorithm that extracts clusters from geotagged tweets by considering spatial heterogeneity. The algorithm employs exponential spline interpolation to determine different search radiuses for cluster detection. Moreover, in addition to spatial proximity, textual similarities among tweets are also taken into account by the algorithm. In order to examine the efficiency of the algorithm, geotagged tweets collected during a hurricane in the United States were used for event detection. The output clusters of VDCT have been compared to those of DBSCAN. Visual and quantitative comparison of the results proved the feasibility of the proposed method.

Multidisciplinary Digital Publishing Institute
Journals 2019 EN

Comparison of Main Approaches for Extracting Behavior Features from Crowd Flow Analysis

Zeinab Ebrahimpour · Wanggen Wan · Ofelia Cervantes +2 more

Extracting features from crowd flow analysis has become an important research challenge due to its social cost and the impact of inadequate planning of high-quality services and security monitoring on the lives of citizens. This paper descriptively reviews and compares existing crowd analysis approaches based on different data sources. This survey provides the fundamentals of crowd analysis and considers three main approaches: crowd video analysis, crowd spatio-temporal analysis, and crowd social media analysis. The key research contributions in each approach are presented, and the most significant techniques and algorithms used to improve the precision of results that could be integrated into solutions to enhance the quality of services in a smart city are analyzed.

Multidisciplinary Digital Publishing Institute