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Concept: Grade

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Application of social network analysis to education has revealed how social network positions of K-12 students correlate with their behavior and academic achievements. However, no study has been conducted on how their social network influences their academic progress over time. Here we investigated correlations between high school students' academic progress over one year and the social environment that surrounds them in their friendship network. We found that students whose friends' average GPA (Grade Point Average) was greater (or less) than their own had a higher tendency toward increasing (or decreasing) their academic ranking over time, indicating social contagion of academic success taking place in their social network.

Concepts: Grade, Education, Sociology, High school, Social network, Network theory, Network science, Complex network

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This study examined the effects of an acute bout of brief, high-intensity interval exercise on off-task classroom behaviour in primary school students. A grade 4 class (n = 24) and a grade 2 class (n = 20) were exposed to either a no-activity break or an active break that consisted of “FUNtervals”, a high-intensity interval protocol, on alternating days for 3 weeks. No-activity days consisted of a 10-min inactive break while FUNterval days consisted of a 4-min FUNterval completed within a 10-min break from regular class activities. Off-task behaviour was observed for 50 min after each no-activity/FUNterval break, with the amount of time students spent off-task (motor, passive, and verbal behaviour) being recorded. When comparing no-activity breaks with FUNtervals the grade 4 class demonstrated reductions in both passive (no activity = 29% ± 13% vs. FUNterval = 25% ± 13%, p < 0.05, effect size (ES) = 0.31) and motor (no activity = 31% ± 16% vs. FUNterval = 24% ± 13%, p < 0.01, ES = 0.48) off-task behaviour following FUNtervals. Similarly, in the grade 2 class, passive (no activity = 23% ± 14% vs. FUNterval = 14% ± 10%, p < 0.01, ES = 0.74), verbal (no activity = 8% ± 8% vs. FUNterval = 5% ± 5%, p < 0.05, ES = 0.45), and motor (no activity = 29% ± 17% vs. FUNterval = 14% ± 10%, p < 0.01, ES = 1.076) off-task behaviours were reduced following FUNtervals. In both classrooms the effects of physical activity were greatest in those students demonstrating the highest rates of off-task behaviour on no-activity days. These data demonstrate that very brief high-intensity bouts of exercise can improve off-task behaviour in grade 2 and 4 students, particularly in students with high rates of such behaviour.

Concepts: Grade, Physical exercise, Demonstration, High school, Primary school, Primary education, Gymnasium, Classroom

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Skeletal maturation is divisible to three main components; the time of appearance of an ossification center, its change in morphology and time of fusion to a primary ossification center. With regard to the knee, the intermediate period between appearance and fusion of the ossification centers extends over a period of greater than 10 years. This study aims to investigate radiographically the age at which morphological changes of the epiphyses at the knee occur in a modern Irish population. Radiographs of 221 subjects (137 males; 84 females) aged 9-19 years were examined. Seven nonmetric indicators of maturity were assessed using criteria modified from the Roche, Wainer, and Thissen method and Pyle and Hoerr’s atlas of the knee. Reference charts are presented which display the timeline for each of the grades of development of the seven indicators. Mean age was found to increase significantly with successive grades of development of each of the seven indicators. A significant difference was noted between males and females at the same grade of development for six of the seven indicators. The narrowest age range reported for a single grade of development was 2.2 years for Grade 2 of development of the tibial tuberosity for males. The information on changing morphology of the epiphyses at the knee in the present study may provide an adjunct to methods used for evaluation of skeletal maturity before surgery for orthopedic disorders or to evaluate skeletal age in clinical scenarios where either delayed or precocious skeletal maturation is suspected. Clin. Anat. 26:755-767, 2013. © 2012 Wiley Periodicals, Inc.

Concepts: Time, Bone, Human, Grade, The Age, Change, Endochondral ossification, Irish language

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Canine lymphoma is the neoplasm most often treated by chemotherapy, yet there are few data to correlate response to therapy with its different subtypes. This study is based on biopsy specimens from 992 dogs for which lymphoma was the clinical diagnosis. All cases were phenotyped by immunohistochemistry for CD3 and CD79alpha. Cases with histiocytic proliferation were evaluated immunohistochemically for CD18. Clonality was verified in 12 cases by polymerase chain reaction (PCR). Survival (event time) data and complete survival information (cause of death or time to last follow-up) were available on 456 dogs. Additional covariate information when available included size, age, sex, phenotype, stage and grade of lymphoma, mitotic index, and treatment protocol. Because of the many subtypes of B- and T-cell lymphoma, the cases were grouped into 7 diagnostic categories: (1) benign hyperplasia; (2) low-grade B-cell; (3) high-grade B- and T-cell; (4) low-grade T-cell; (5) centroblastic large B-cell of all mitotic grades (subdivided by clinical stage); (6) immunoblastic large B-cell of all mitotic grades, and (7) high-grade peripheral T-cell. Grouping was determined by histological grade (based on mitotic rate/400× field, with low-grade 0-5, intermediate 6-10, and high-grade >10) and stage for survival function estimation. No association with survival was found for size (based on breed of dog) or sex. All diagnostic categories of indolent or low-grade type had low mitotic rates, whereas those with clinically high grades had high mitotic rates. The diagnostic category with the most cases was centroblastic large B-cell lymphoma. Compared with dogs in this largest represented group of lymphomas, dogs with high-grade lymphomas had significantly higher mortality rates, and dogs with low-grade T-cell lymphomas had significantly lower mortality rates. Treatments for high-, intermediate-, and low-grade lymphomas were divided into 4 groups: absence of treatment, chemotherapy with or without hydroxydaunorubicin, and only prednisone. Dogs with low-grade T-cell (T-zone) lymphomas had the longest median survival (622 days), whereas the shortest median survival was in dogs with T-cell high-grade (peripheral T-cell) subtype (162 days). The dogs with centroblastic large B-cell lymphomas had a median survival of 127 days with low stage, 221 days with intermediate stage, and 215 days with advanced stage. Dogs with T-zone lymphoma were probably diagnosed in later stages of disease because of the lack of signs associated with progression. As with human lymphomas, a histological diagnosis with immunophenotyping is a minimal requirement for diagnosis of a specific subtype.

Concepts: Cancer, Grade, B cell, Types of cancer, Lymphoma, Non-Hodgkin lymphoma, B-cell lymphoma, T-cell lymphoma

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Wide excision is the major recommendation for management of soft-tissue sarcomas. Pathologic reports of postexcision sarcomas revealed very close (within 2 mm) but clear excision margins. This investigation was a retrospective study to determine whether wide reexcision plus radiotherapy (R/T), or R/T only, yielded better outcomes. MATERIALS AND METHODS: We evaluated our soft-tissue sarcoma cases who had received wide excision in the past 15 years. The surgical margin conditions (negative, positive, or close margins) and pathologic status were evaluated. The different management modalities for each condition were also evaluated individually and discussed. RESULTS: There were 73 cases from 1995 to 2010 in our section who had received wide excision. The overall recurrence rate was 24.6%. In cases with margin positive, the recurrence rate was 20% (2/8) after quick reexcision. However, the recurrence rate was 56% in patients who received R/T but without quick reexcision. In cases with close resection margins (<2 mm) with no reexcision but R/T, the recurrence rate was 45%, and all of them had a high-grade malignancy sarcoma. The other nonrecurrence cases (55%) had low-grade malignancy or well-differentiated sarcoma.In summary, in cases with positive margin sarcoma, quick reexcision plus R/T was suggested and the recurrence rate was relatively low. In soft-tissue sarcoma cases with close margin, we believe quick reexcision plus R/T is necessary, especial in high-grade, poor differentiated soft-tissue sarcomas.

Concepts: Cancer, Soft tissue sarcoma, Grade, Surgery, Retrospective, Types of cancer, Sarcoma, Alveolar soft part sarcoma

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The voiding cystourethrogram (VCUG) is a commonly employed radiographic test used in the management of vesicoureteral reflux (VUR). Recently, the reliability of VCUG to accurately grade VUR has been questioned. The purpose of this study is to examine reliability of the VCUG for the grading of VUR in a setting mimicking daily practice in a busy pediatric hospital.

Concepts: Grade, Urology, Vesicoureteral reflux, Voiding cystourethrogram, Children's hospital

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PURPOSE: Differentiation between recurrence and radiation necrosis in patients with glioma is crucial, since the two entities have completely different management and prognosis. The purpose of the present study was to compare the efficacies of (18)F-FDG PET/CT and 3,4-dihydroxy-6-[(18)F]fluoro-phenylalanine ((18)F-FDOPA) PET/CT in detection of recurrent gliomas. METHODS: A total of 28 patients (age 38.82 ± 1.25 years; 85.7 % men) with histopathologically proven glioma with clinical/imaging suspicion of recurrence were evaluated using (18)F-FDG PET/CT and (18)F-FDOPA PET/CT. (18)F-FDG PET/CT and (18)F-FDOPA PET/CT images were evaluated qualitatively and semiquantitatively. The combination of clinical follow-up, repeat imaging and/or biopsy (when available) was taken as the reference standard. RESULTS: Based on the reference standard, 21 patients were positive and 7 were negative for tumour recurrence. The sensitivity, specificity and accuracy of (18)F-FDG PET/CT were 47.6 %, 100 % and 60.7 %, respectively, and those of (18)F-FDOPA PET/CT were 100 %, 85.7 % and 96.4 %, respectively. The results of (18)F-FDG PET/CT and (18)F-FDOPA PET/CT were concordant in 57.1 % of patients (16 of 28) and discordant in 42.9 % (12 of 28). The difference in the findings between (18)F-FDG PET/CT and (18)F-FDOPA PET/CT was significant (P = 0.0005, McNemar’s test). The difference was significant for low-grade tumours (P = 0.0039) but not for high-grade tumours (P = 0.250). CONCLUSION: (18)F-FDOPA PET/CT is highly sensitive and specific for detection of recurrence in glioma patients. It is superior to (18)F-FDG PET/CT for this purpose and is especially advantageous in patients with low-grade gliomas.

Concepts: Cancer, Grade, Glioma, Brain tumor, Anatomical pathology, Tumor, Recurrence relation, McNemar's test

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PURPOSE: To retrospectively report and grade the peri-operative complications of transurethral resection of the prostate (TURP) using the modified Clavien classification system (MCCS) and validate whether Charlson comorbidity index (CCI) predicts the complications after TURP. MATERIALS AND METHODS: Between September 2006 and 2012, data of 722 patients who underwent TURP were analyzed after excluding patients with incomplete data (n = 40). Data recorded included the age, prostate volume, operative time, mean prostatic tissue removed and duration of hospitalization while complications were recorded using the MCCS. Preexisting comorbidities were evaluated using the CCI, and patients were classified into 3 CCI score categories (0, 1, ≥2). RESULTS: Two hundred and forty-four complications were seen in 145 (20 %) patients. CCI score was “0” for 480 patients (66.5 %), “1” for 184 patients (25.5 %) and “≥2” for 58 patients (8 %). Significant difference was observed between patient groups with CCI score 0, 1 and ≥2 for mean age, prostatic weight, operative time, weight of prostatic chips and duration of hospitalization. Similarly, a significant difference in occurrence of various MCCS grades of complication among patients groups with different CCI score was observed. CONCLUSION: Grades I, II and III complications constituted the main bulk (90 %) while grade IV were less common (<8 %) and grade V was rare (1 %) after TURP. Men with higher CCI score had a significantly higher rate of morbidity than those with a lower score. The present study is the first to validate that CCI can predict complications of TURP recorded according to the MCCS.

Concepts: Time, Patient, Grade, Urology, Prostate, Comorbidity, Prostatic stent, Transurethral resection of the prostate

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PURPOSE:: To evaluate the impact of conjunctivochalasis (CCh) and its severity on the ocular surface parameters of glaucoma subjects treated with topical antiglaucomatous medication. MATERIALS AND METHODS:: One hundred patients with the clinical diagnosis of glaucoma were recruited for this study. CCh was graded based on the extent of inferior lid margin involvement as follows: 1=single (temporal) location, 2=two locations (nasal and temporal), and 3=whole lid. For all the subjects, the break-up time (BUT), lissamine green (LG) staining, and Schirmer test (under topical anesthesia) was performed for both eyes. Ocular Surface Disease Index (OSDI) questionnaire scores were also noted for each subject. Student t test, Mann-Whitney U test, and Kruskal-Wallis test was used for statistical evaluations. RESULTS:: Sixty-three subjects had evidence of CCh; 32 had grade 1, 24 had grade 2, 7 had grade 3 CCh, and 37 glaucoma patients had no evidence of CCh. There were significant differences in the BUT scores (7.2±2.7 vs. 10.1±2.4 s, P<0.001), Schirmer values (7.7±3.9 vs. 13.3.±4.0 mm, P<0.001), LG staining score (1.6±1.0 vs. 0.3±0.5, P<0.001), and the OSDI scores (19.4±17.2 vs. 6.7±5.2, P<0.001) between patients who had CCh and those without CCh. The BUT scores and Schirmer test values of patients with grades 2 and 3 CCh were significantly lower than those of grade 1 CCh and those without CCh (P<0.001). The LG grading and OSDI scores were significantly higher in grade 2 and 3 patients as compared with those with grade 1 CCh and those without CCh (P<0.001). CONCLUSIONS:: The functional characteristics of the ocular surface appear to be adversely influenced by the presence and the extent of CCh in glaucoma patients.

Concepts: Statistical tests, Statistics, Grade, Mann–Whitney U, Non-parametric statistics, Receiver operating characteristic, Topical anesthetic, Schirmer's test

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PURPOSE: A single treatment of (131)I-rituximab in patients with B cell non-Hodgkin lymphoma (NHL) showed a modest rate of response (29 %) in a relatively short duration (median 2.9 months). On the basis of this result, we investigated whether repeated treatment with (131)I-rituximab could improve the response. PATIENTS AND METHODS: Thirty-one patients with relapsed or refractory B cell NHL received unlabeled rituximab (70 mg) immediately prior to the administration of a therapeutic dose of (131)I-rituximab. The tumor response was evaluated 1 month later by contrast-enhanced (18)F-fluorodeoxyglucose positron emission tomography/computed tomography. Radioimmunotherapy (RIT) was repeated at 4-week intervals. RESULTS: A total of 87 cycles of RIT were administered. Repeated RIT yielded twofold increases in response rate (68 %) and in median response duration (8.6 months). This protocol also induced a favorable response in patients with an aggressive histology compared to that induced by a single treatment (50 vs. 9 %, respectively, p = 0.063). The toxicities were principally hematologic with grade 4 thrombocytopenia occurring in 12 % and neutropenia occurring in 17 % of the 85 assessable cycles. CONCLUSIONS: Compared to a single treatment, repeated RIT with (131)I-rituximab increased the response rate and duration for patients with relapsed or refractory B cell NHL, including those with an aggressive histology.

Concepts: Medicine, Cancer, Grade, Positron, Leukemia, Lymphoma, Blood disorders, Non-Hodgkin lymphoma