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41.
Michela Azzarito Sreenath P. Kyathanahally Yaël Balbastre Maryam Seif Claudia Blaiotta Martina F. Callaghan John Ashburner Patrick Freund 《Human brain mapping》2021,42(1):220-232
To validate a simultaneous analysis tool for the brain and cervical cord embedded in the statistical parametric mapping (SPM) framework, we compared trauma‐induced macro‐ and microstructural changes in spinal cord injury (SCI) patients to controls. The findings were compared with results obtained from existing processing tools that assess the brain and spinal cord separately. A probabilistic brain‐spinal cord template (BSC) was generated using a generative semi‐supervised modelling approach. The template was incorporated into the pre‐processing pipeline of voxel‐based morphometry and voxel‐based quantification analyses in SPM. This approach was validated on T1‐weighted scans and multiparameter maps, by assessing trauma‐induced changes in SCI patients relative to controls and comparing the findings with the outcome from existing analytical tools. Consistency of the MRI measures was assessed using intraclass correlation coefficients (ICC). The SPM approach using the BSC template revealed trauma‐induced changes across the sensorimotor system in the cord and brain in SCI patients. These changes were confirmed with established approaches covering brain or cord, separately. The ICC in the brain was high within regions of interest, such as the sensorimotor cortices, corticospinal tracts and thalamus. The simultaneous voxel‐wise analysis of brain and cervical spinal cord was performed in a unique SPM‐based framework incorporating pre‐processing and statistical analysis in the same environment. Validation based on a SCI cohort demonstrated that the new processing approach based on the brain and cord is comparable to available processing tools, while offering the advantage of performing the analysis simultaneously across the neuraxis. 相似文献
42.
Edwin Jabbari Shunsuke Koga Rebecca R Valentino Regina H Reynolds Raffaele Ferrari Manuela M X Tan James B Rowe Clifton L Dalgard Sonja W Scholz Dennis W Dickson Thomas T Warner Tamas Revesz Günter U Höglinger Owen A Ross Mina Ryten John Hardy Maryam Shoai Huw R Morris 《Lancet neurology》2021,20(2):107-116
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Maryam Gheisarifar Geoffrey A. Thompson Carl Drago Fahimeh Tabatabaei Morteza Rasoulianboroujeni 《The Journal of prosthetic dentistry》2021,125(1):155-164
Statement of problemSoft-tissue attachment to different surfaces may play a pivotal role in the long-term success of dental implants. However, studies on the issue, especially on newer materials, are sparse.PurposeThe purpose of this in vitro study was to evaluate the viability and adhesion of human gingival fibroblasts (HGFs) on different implant abutment materials with specific surface modifications.Material and methodsOne hundred and fifty specimens in 6 experimental groups were evaluated: smooth-machined titanium alloy (Ti), laser-modified titanium (TiL), smooth-machined polyetheretherketone (PEEK) (P), laser-modified PEEK (PL), plasma-treated PEEK (PP), laser- and plasma-treated PEEK (PLP). Machined Ti was considered as the control group. Surface roughness (Sa), water contact angle (WCA), and X-ray photoelectron spectroscopy (XPS) were measured. HGF attachment and proliferation were observed at 1, 3, and 7 days after cell seeding. Comparison of the means among the groups was performed with 1-way analysis of variance (ANOVA) with post hoc comparison using the Tukey test (α=.05).ResultsSa values of the laser modified groups were significantly higher than those of the nonmodified (smooth-machined) groups (P<.001). WCAs were significantly different among PEEK groups, and plasma-sprayed groups had the lowest WCAs. XPS analysis of both Ti and PEEK groups showed laser treatment did not have any significant effect on the surface composition of the PEEK as the same bonds with similar ratio/fraction were detected in the spectrum of the modified specimens. Scanning electron microscopy (SEM) revealed more functionally oriented HGF cells on the laser-grooved surfaces. On the first, third, and seventh day of proliferation, the titanium groups showed no significant differences (P>.05). On the first and third days of proliferation, the plasma sprayed groups (PP, PLP) showed significantly greater proliferation than all experimental groups (P<.001). On the seventh day of proliferation, statistically significant differences were observed between all PEEK groups and between all PEEK groups and the Ti group (P<.001), with the exception of the PL and P groups and the PLP and Ti groups (P>.05).ConclusionsLaser-modified titanium and PEEK surfaces led to guided gingival fibroblast attachment. Plasma treatment of PEEK surfaces increased the wettability of this polymer and improved proliferation of HGF. 相似文献
44.
Najmeh Movahhedian Maryam Paknahad Fatemeh Abbasinia Leila Khojatepour 《Journal of maxillofacial and oral surgery》2021,20(1):105
BackgroundThe sphenoid sinus is considered as the most variable pneumatized structure of the skull.PurposeThe aim of the present study was to determine the prevalence of the Onodi cell as well as to evaluate the relationship between the sphenoid sinus type of pneumatization and the presence of surrounding neurovascular protrusion using cone beam computed tomography (CBCT).MethodsThe CBCT images of 500 patients/996 sides [203 males (40.6%) and 297 females (59.4%)] were analyzed in this study. The type of sphenoid sinus pneumatization, prevalence of internal carotid artery (ICA) and optic nerve (ON) protrusion and dehiscence, and also the frequency of Onodi cell were assessed.ResultsThe percentages of the conchal, presellar, sellar, postsellar (a), and postsellar (b) types of pneumatization were 1%, 11.5%, 35.5%, 38.9%, and 13.1%, respectively. The more the sphenoid sinuses pneumatized, the greater the frequency of ON and ICA protrusion and dehiscence of their wall to the sinus. The prevalence of Onodi cell was 38.8%. A significant correlation was found between ON dehiscence and the presence of Onodi cells.ConclusionThe present study demonstrated a significant relationship between the sinus type and frequency of neurovascular protrusions. Therefore, the sphenoid sinus extent of pneumatization might be useful in predicting the risk of iatrogenic damage to the surrounding structures. 相似文献
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46.
Maryam Zarrabi Mohammadali Nazarinia Abbas Rahimi Jaberi Nasser Gholijani Zahra Amirghofran 《Medical principles and practice》2021,30(2):146
ObjectiveInterleukin (IL)-38 is a newly discovered member of the IL-1 cytokine family with a proposed anti-inflammatory profile. We studied the probable role of this cytokine in the pathogenesis of two autoimmune diseases: multiple sclerosis (MS) and systemic sclerosis (SSc).Subjects and MethodsA total of 87 MS patients and 86 SSc patients (40 new and recently untreated cases and 46 treated cases) were selected for this study. Eighty-seven and 80 age- and sex-matched healthy subjects were included as controls for MS and SSc, respectively. Clinical and paraclinical features of the patients were recorded at the time of sampling. Serum IL-38 was measured by ELISA.ResultsLevels of serum IL-38 did not significantly differ between the total MS or SSc patients compared to controls. However, levels of IL-38 were significantly higher in newly diagnosed patients of MS (206.43 ± 38.97 pg/mL, p < 0.0001) than in those previously treated (158.04 ± 39.45 pg/mL). Similarly, new/recently untreated cases of SSc patients showed increased IL-38 levels (185.19 ± 36.27 pg/mL, p = 0.001) compared to treated patients (166.82 ± 33.08 pg/mL). IL-38 levels in newly diagnosed MS patients (p = 0.007) and new/recently untreated SSc patients (p = 0.032) were significantly higher than those in healthy controls.ConclusionThe higher serum levels of IL-38 in new or recently untreated cases of MS and SSc patients than in treated patients and healthy controls suggest the possible role of this cytokine in the development of these diseases or as part of a feedback loop to attenuate the inflammatory conditions in early stages of these diseases. 相似文献
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48.
Omid Khalilzadeh Maryam Rahimian Vinay Batchu Harshna V. Vadvala Robert A. Novelline Garry Choy 《Diagnostic and interventional radiology (Ankara, Turkey)》2015,21(5):423-427
PURPOSE
A second opinion is a valuable resource in confirming proper medical diagnosis and treatment. This study evaluates the effectiveness of second-opinion radiology consultations to reassess the cervical spine computed tomography (CT) scans of the trauma patients referred to our hospital.METHODS
Cervical spine CT scans of 301 consecutive adult trauma patients, who were referred to our hospital from outside institutions, were analyzed. The emergency radiologists at our institution completed the over-read reports on the CT images obtained at the outside facilities. A single radiologist compared the outside- and over-read reports and determined the discrepancy of the radiologic reports.RESULTS
Based on the outside reports, 31% of the CT scans had cervical traumatic injury. In 92% of patients, the first-read and the over-read reports had consistent radiologic findings. About 90% of the positive, and 93% of the negative radiologic findings, were reported consistently in the over-read reports. Our analysis showed that the over-read reporting resulted in reassurance of negative findings in 63%; confirmation of positive findings in 29%; clearing a false diagnosis in 3%; and detection of a missed diagnosis in 5%. A rescan was done in 80% of patients with inconsistent and 20% of patients with consistent findings (P < 0.05). The most common missed radiologic findings in the first-reports were transverse and spinous process fractures and the most common misdiagnoses were dens fractures.CONCLUSION
For a service offering second-opinion consultations on cervical spine trauma, review of outside CT studies improves diagnosis and benefits patient care.The quality of healthcare has become a target of increasing public scrutiny and governmental concern while radiologic evaluation has assumed an increasingly important role in the diagnosis and management of patients (1). Public attention and awareness have increased and amplified the focus on the quality of healthcare (2). Some medical errors are extremely costly particularly with respect to patient morbidity and mortality.Patients referred to the tertiary care centers often arrive with radiologic imaging having already been performed at the primary institution. As part of the care to be delivered by the radiologists at the referral center, a second-opinion interpretation of the imaging studies is often requested, and the formal reports are incorporated into the patient’s permanent medical record at the referral institution where the patient’s management and treatment are determined.The added value of the point-of-care second interpretations can be viewed from the medical perspective of guiding and expediting appropriate treatment as well as from the financial perspective of avoiding unnecessary studies, at times incurring additional patient radiation exposure, when initial examinations need to be repeated or when additional examinations are suggested by the radiologist at an outside institution (3).Multidetector CT is an essential part of the assessment of patients suspected of having cervical spine injury after trauma. Despite all the advantages of multidetector CT, suspected spinal injury continues to be a daily challenge in clinical practice (4). Spine injuries are frequently missed; therefore, a second opinion can potentially improve the diagnosis (5). The purpose of this study was to evaluate the effectiveness of second-opinion radiology consultations to reassess the cervical spine CT scans of the trauma patients referred to our hospital. 相似文献49.
50.