James R. Cook

bcl-2 Expression by Multicolor Flow Cytometric Analysis Assists in the Diagnosis of Follicular Lymphoma in Lymph Node and Bone Marrow

The expression of bcl-2, CD10, and CD20 was examined by multicolor flow cytometry in 78 samples including lymph node or other tissue biopsy specimens containing follicular lymphoma (FL; n = 17), reactive hyperplasia (RH; n = 28), or other malignant lymphomas (n = 20), as well as bone marrow aspirates (n = 13). The presence of CD10+ cells with high bcl-2 expression predicted the presence of FL rather than RH with a positive predictive value of 100% and negative predictive value of 96%. CD10+ cells with high bcl-2 expression also were found in a subset of diffuse large B-cell lymphomas and were otherwise rare in other types of malignant lymphoma. In contrast with immunohistochemical studies, a reduced but apparently measurable level of bcl-2 was present in benign follicular center cells. Hematogones showed lower bcl-2 levels than did FL cells in the bone marrow, and neutrophils were bcl-2-. Measurement of bcl-2 expression levels by multiparameter flow cytometry offers a rapid, quantitative assessment that may assist in the diagnosis of FL in lymph nodes or bone marrow, even when other CD10+ cells or admixed normal B cells are present.

Benign CD10-positive T cells in reactive lymphoid proliferations and B-cell lymphomas.

Recent reports have indicated that the neoplastic T cells of angioimmunoblastic T-cell lymphoma express CD10. It has been suggested that the demonstration of a CD10+ T-cell population may assist in establishing a diagnosis of angioimmunoblastic T-cell lymphoma and in distinguishing angioimmunoblastic T-cell lymphoma from other peripheral T-cell lymphomas. It has been unclear, however, whether this phenotypically unusual T-cell population might be present in other settings as well. In this report, we have retrospectively examined 64 cases of lymph node and solid tissue biopsies for the presence of CD10+ T cells using multicolor flow cytometry. Discrete populations of CD10+ T cells were found in 5 of 28 cases (18%) of reactive lymphoid hyperplasia, 4 of 17 cases (23%) of follicular lymphoma, and 9 of 19 cases (47%) of marginal zone B-cell lymphomas. The CD10+ T cells constituted 1–6% of total cells analyzed and ≤14% of the total T-cell population. Using two-color immunohistochemical stains, many of the CD10+ PAX5-negative presumptive T cells were found to be located within germinal centers. These findings indicate that a normal small subset of CD10+ peripheral T cells exists and, at least when present in small numbers, should not be considered an indication of a T-cell neoplasm.

Rater reliability and concurrent validity of the Keyboard Personal Computer Style instrument (K-PeCS)

This paper describes the inter-rater and intra-rater reliability, and the concurrent validity of an observational instrument, the Keyboard Personal Computer Style instrument (K-PeCS), which assesses stereotypical postures and movements associated with computer keyboard use. Three trained raters independently rated the video clips of 45 computer keyboard users to ascertain inter-rater reliability, and then re-rated a sub-sample of 15 video clips to ascertain intra-rater reliability. Concurrent validity was assessed by comparing the ratings obtained using the K-PeCS to scores developed from a 3D motion analysis system. The overall K-PeCS had excellent reliability [inter-rater: intra-class correlation coefficients (ICC)=.90; intra-rater: ICC=.92]. Most individual items on the K-PeCS had from good to excellent reliability, although six items fell below ICC=.75. Those K-PeCS items that were assessed for concurrent validity compared favorably to the motion analysis data for all but two items. These results suggest that most items on the K-PeCS can be used to reliably document computer keyboarding style.

Nodal marginal zone B-cell lymphoma with a novel t(X;5)(q28;q22): conventional and molecular cytogenetic analysis

Cytogenetic studies provide important information for the diagnosis and classification of malignant lymphomas that in some cases also has prognostic significance. Furthermore, the investigation of isolated novel cytogenetic findings in malignant lymphoma has led to the discovery of many important oncogenes and tumor suppressor genes. For this reason, a case of nodal marginal zone B-cell lymphoma in a 72-year-old woman is described in which analysis by conventional and molecular cytogenetic techniques demonstrated the presence of a t(X:5)(q28;q22) as the sole chromosomal abnormality. This translocation has not been previously reported in the literature.

CHINA’S NEW SORROW: WATER-MANAGEMENT POLICIES, ENVIRONMENTAL DEGRADATION, AND SALAR-TIBETAN MINORITY RELATIONS IN QINGHAI PROVINCE, 1862–1978

This article analyzes the effect of post-1949 policies on minority peoples in China’s watershed—Qinghai province. Salar and Tibetan peoples had lived in relative harmony for centuries in Xunhua County. Access to the Tibetan highlands and a monopoly on wool production had provided Tibetan herders with an upper hand. New policies that encouraged agricultural production over the course of the twentieth century not only brought radical changes to these long-standing relationships but also initiated new strains on the local environment. The Mao era saw a particularly rapid expansion of new water projects designed to tame the Yellow River. The resulting environmental catastrophe is a major contributing factor to the river’s current inability to flow to the Yellow Sea.

Symptoms elicited in persons with vestibular dysfunction while performing gaze movements in optic flow environments

INTRODUCTION People with vestibular disorders often experience space and motion discomfort when exposed to moving or highly textured visual scenes. The purpose of this study was to measure the type and severity of symptoms in people with vestibular dysfunction during coordinated head and eye movements in optic flow environments. METHODS Seven subjects with vestibular disorders and 25 controls viewed four different full-field optic flow environments on six different visits. The optic flow environments consisted of textures with various contrasts and spatial frequencies. Subjects performed 8 gaze movement tasks, including eye saccades, gaze saccades, and gaze stabilization tasks. Subjects reported symptoms using Subjective Units of Discomfort (SUD) and the Simulator Sickness Questionnaire (SSQ). Self-reported dizziness handicap and space and motion discomfort were also measured. RESULTS/CONCLUSION Subjects with vestibular disorders had significantly greater discomfort, oculomotor and disorientation symptoms, with some amount of symptoms in 55-60% of the trials, compared with control subjects, who had symptoms in less than 20% of the trials. The magnitude of the symptoms increased during each visit, but did not depend on the optic flow condition. Subjects who reported greater dizziness handicap and space and motion discomfort had greater severity of symptoms during the experiment (Spearman rho > 0.78). Compared with controls, subjects with vestibular disorders had about 10 deg less head excursion during the gaze saccade tasks. Overall, performance of gaze pursuit and gaze stabilization tasks in moving visual environments elicited greater symptoms in subjects with vestibular disorders compared with healthy subjects.