4,113 research outputs found
Functional and anatomic correlates of two frequently observed temporal lobe seizure-onset patterns.
Intracranial depth electrode EEG records of 478 seizures, recorded in 68 patients undergoing diagnostic monitoring with depth electrodes, were evaluated to investigate the correlates of electrographic onset patterns in patients with temporal lobe seizures. The seizure onsets in 78% of these patients were identified as either hypersynchronous onsets, beginning with low-frequency, high-amplitude spikes, or low-voltage fast (LVF) onsets, increasing in amplitude as the seizure progressed. The number of patients (35) having hypersynchronous seizure onsets was nearly twice that of patients (18) having LVF onsets. Three major differences were seen among patients with the two seizure-onset patterns. When compared with patients having LVF onsets, patients with hypersynchronous seizure onsets had a significantly greater probability of having (1) focal rather than regional seizure onsets (p < 0.01), (2) seizures spreading more slowly to the contralateral mesial temporal lobe (p < 0.003), and (3) cell counts in resected hippocampal tissue showing greater neuronal loss (p < 0.001). The results provide evidence that the most frequent electrographic abnormality associated with mesial temporal seizures is local hypersynchrony, a condition associated with major neuronal loss in the hippocampus. The results also indicate that LVF seizure onsets more frequently represent widely distributed discharges, which interact with and spread more rapidly to surrounding neocortical areas
Upper lid crease approach for margin rotation in trachomatous cicatricial entropion without external sutures
ABSTRACT Purpose: To describe the use of a lid crease incision for upper eyelid margin rotation in cicatricial entropion combining internal traction on the anterior lamella, tarsotomy, and tarsal overlap without external sutures. Methods: Surgical description: The main steps of the procedure consisted of exposure of the entire tarsal plate up to the eyelashes followed by tarsotomy through the conjunctiva. A double-armed 6.0 polyglactin suture was then passed through the distal tarsal fragment to the marginal section of the orbicularis oculi muscle. As the sutures were tied, the distal tarsus advanced over the marginal section, and traction was exerted on the marginal strip of the orbicularis muscle. There were no bolsters or external knots. The pretarsal skin-muscle flap was closed with a 6.0 plain gut suture. Results: We used this procedure at a tertiary hospital in Saudi Arabia from 2013 to 2014. Sixty upper lids of 40 patients (23 women and 17 men) were operated on, with an age range of 44-99 years [mean ± standard deviation (SD) = 70.9 ± 13.01 years]. Bilateral surgery was performed on 21 patients. Follow-up ranged from 1 to 12 months (mean 3.0 ± 2.71 months). Forty percent of the patients (24 lids) had more than 3 months' follow-up. The postoperative lid margin position was good in all cases. Trichiasis (two lashes) was observed in only one patient with unilateral entropion on the medial aspect of the operated lid. Conclusions: The upper lid margin can be effectively rotated through a lid crease incision with internal sutures. The technique combines the main mechanisms of the Wies and Trabut approaches and avoids the use of bolsters or external sutures, which require a second consultation to be removed. Some other lid problems, such as ptosis, retraction, or dermatochalasis, can be concomitantly addressed during the procedure
Point cloud voxel classification of aerial urban LiDAR using voxel attributes and random forest approach
The opportunities now afforded by increasingly available, dense, aerial urban LiDAR point clouds (greater than100 pts/m2) are arguably stymied by their sheer size, which precludes the effective use of many tools designed for point cloud data mining and classification. This paper introduces the point cloud voxel classification (PCVC) method, an automated, two-step solution for classifying terabytes of data without overwhelming the computational infrastructure. First, the point cloud is voxelized to reduce the number of points needed to be processed sequentially. Next, descriptive voxel attributes are assigned to aid in further classification. These attributes describe the point distribution within each voxel and the voxel's geo-location. These include 5 point-descriptors (density, standard deviation, clustered points, fitted plane, and plane's angle) and 2 voxel position attributes (elevation and neighbors). A random forest algorithm is then used for final classification of the object within each voxel using four categories: ground, roof, wall, and vegetation. The proposed approach was evaluated using a 297,126,417 point dataset from a 1 km2 area in Dublin, Ireland and 50% denser dataset of New York City of 13,912,692 points (150 m2). PCVC's main advantage is scalability achieved through a 99 % reduction in the number of points that needed to be sequentially categorized. Additionally, PCVC demonstrated strong classification results (precision of 0.92, recall of 0.91, and F1-score of 0.92) compared to previous work on the same data set (precision of 0.82-0.91, recall 0.86-0.89, and F1-score of 0.85-0.90).This work was funded by the National Science Foundation award 1940145
Is there a gender difference in anatomic features of incisive canal and maxillary environmental bone?
Objectives The effect of gender on anatomic structures and various body systems were illustrated in the literature. The purpose of this study was to identify the influence of gender and tooth loss on incisive canal characteristics and buccal bone dimensions in the anterior maxilla. Materials and methods Computed tomographies ( CTs ) of 417 male and 516 female patients in four dental clinics were included in this study. The diameter and the length of the incisive canal; width and the length of the bone anterior to the canal; palatal bone length, root length, and root width of the central incisor teeth were measured and recorded from CT sections. Results Mean incisive canal length was 11.96 ± 2.73 mm and 10.39 ± 2.47 mm in men and women, respectively, ( P  < 0.05). In men, mean canal diameter was 2.79 ± 0.94 mm whereas in women it was 2.43 ± 0.85 mm and this difference was statistically significant ( P  < 0.05). Men had significant higher buccal bone dimensions (length and width of the bone anterior to the canal) than women. Absence of teeth in the anterior maxilla decreased incisive canal length and buccal bone dimensions; however, canal diameter remain unchanged. Conclusions Present results suggested a gender related differences in anatomic features of incisive canal and surrounding buccal bone. In addition, crestal canal diameter, buccal bone length, and thickness parameters might be different in distinct countries.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99051/1/clr2493.pd
Large firm dominance on countryâs entrepreneurship potentials
This paper aims to determine whether countries where large firms are very dominant have less entrepreneurial activities. There is anecdotal evidence that the continued decline in the business dynamism or the number of start-ups in the United States is said to be partly attributed to large firms. One key explanation is that the regulatory environment tends to favor existing large firms - an environment that allows near monopolies and a protection of tiny entrepreneurial elite. Using the Global Entrepreneurship Monitor (GEM) data together with the World Bank - International Finance Corporation's MSME country indicators, I empirically test whether large firm dominance influences entrepreneurial activities as well as intentions. Using fixed effects regression analysis on unbalanced panel of 40 countries over the period 2002-2007, I found that the entrepreneurship potential of a country is potentially at risk if the growth of large firms' stake in the economy is left unchallenged. In particular, a one percentage point increase in the share of large firms to total employment is associated with 0.35 percentage point lower total early-stage entrepreneurial activity rate, holding other factors constant. Also, worth noting is the sensitivity of entrepreneurial intentions to large firm dominance. A one percentage point increase in the share of large firms to total employment dampens (i.e., by 0.56 percentage point) intentions of latent entrepreneurs to start a business within the next 3 years, other factors remaining constant. This second-order effect of large firm dominance depends heavily on the country's institutions. Thus, it is critical for governments to foster a dynamic system that guarantees free competition and rewards creativity. Likewise, it is necessary to review and amend policies that seem to favor large firms that compromise the establishment as well as growth of smaller enterprises
Evaluation of Maxillary Incisive Canal Characteristics Related to Dental Implant Treatment With Computerized Tomography: A Clinical Multicenter Study
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141666/1/jper0337.pd
Anaphylaxis after prick-to-prick skin test to seafood allergy: A rare adverse event
Allergies to seafood are common all over the world. The prick-to-pricktest is used to diagnose allergic reactions. In this article, a femalepatient suffered an anaphylactic reaction 5 minutes following a Prick-to-Prick skin test. Therefore, it is important to stratify, recognize and treatthe anaphylactic reaction promptly
Single-cell sequencing reveals clonal expansions of pro-inflammatory synovial CD8 T cells expressing tissue-homing receptors in psoriatic arthritis
Psoriatic arthritis (PsA) is a debilitating immune-mediated inflammatory arthritis of unknown pathogenesis commonly affecting patients with skin psoriasis. Here we use complementary single-cell approaches to study leukocytes from PsA joints. Mass cytometry demonstrates a 3-fold expansion of memory CD8 T cells in the joints of PsA patients compared to peripheral blood. Meanwhile, droplet-based and plate-based single-cell RNA sequencing of paired T cell receptor alpha and beta chain sequences show pronounced CD8 T cell clonal expansions within the joints. Transcriptome analyses find these expanded synovial CD8 T cells to express cycling, activation, tissue-homing and tissue residency markers. T cell receptor sequence comparison between patients identifies clonal convergence. Finally, chemokine receptor CXCR3 is upregulated in the expanded synovial CD8 T cells, while two CXCR3 ligands, CXCL9 and CXCL10, are elevated in PsA synovial fluid. Our data thus provide a quantitative molecular insight into the cellular immune landscape of psoriatic arthritis
Single-cell sequencing reveals clonal expansions of pro-inflammatory synovial CD8 T cells expressing tissue-homing receptors in psoriatic arthritis.
Psoriatic arthritis (PsA) is a debilitating immune-mediated inflammatory arthritis of unknown pathogenesis commonly affecting patients with skin psoriasis. Here we use complementary single-cell approaches to study leukocytes from PsA joints. Mass cytometry demonstrates a 3-fold expansion of memory CD8 T cells in the joints of PsA patients compared to peripheral blood. Meanwhile, droplet-based and plate-based single-cell RNA sequencing of paired T cell receptor alpha and beta chain sequences show pronounced CD8 T cell clonal expansions within the joints. Transcriptome analyses find these expanded synovial CD8 T cells to express cycling, activation, tissue-homing and tissue residency markers. T cell receptor sequence comparison between patients identifies clonal convergence. Finally, chemokine receptor CXCR3 is upregulated in the expanded synovial CD8 T cells, while two CXCR3 ligands, CXCL9 and CXCL10, are elevated in PsA synovial fluid. Our data thus provide a quantitative molecular insight into the cellular immune landscape of psoriatic arthritis
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