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Biomedical subjects

J R Anderson

Publications and source records attributed to J R Anderson.

At least 109 records · Page 6Linked to original sources
PubMed1998

Epidemiology of the non-Hodgkin's lymphomas: distributions of the major subtypes differ by geographic locations. Non-Hodgkin's Lymphoma Classification Project.

BACKGROUND: There has been no previous systematic study of the distribution of the major subtypes of non-Hodgkin's lymphoma (NHL) across geographic regions, although there have been isolated reports of such differences. DESIGN: As part of a clinical evaluation of the International Lymphoma Study Group (ILSG) classification of NHL, we classified 1378 NHLs from eight different geographic sites (Omaha, NE, USA; Vancouver, BC, Canada; Capetown, South Africa; London, England; Würzburg/Göttingen, Germany; Lyon, France; Locarno/Bellinzona, Switzerland; and Hong Kong) using the ILSG classification. RESULTS: Substantial differences were found in the distribution of the major subtypes of NHL across geographic regions (P < 0.0001). A greater percentage of follicular lymphoma was seen in North America, London and Capetown (31% versus 14% at other sites). Peripheral T-cell lymphoma was more common in London, Capetown and Hong Kong (9%) than elsewhere (3%). In Locarno/Bellinzona, higher percentages of mediastinal large B-cell lymphoma (9% versus 2% elsewhere) and mantle cell lymphoma (14% versus 6% elsewhere) were seen. Angiocentric nasal T-/NK-cell lymphoma was only seen in Hong Kong (8%) and Lyon (2%). CONCLUSIONS: Our study provides evidence that the distribution of NHL subtypes differs by geographic region. These findings suggest that geographical differences in etiologic or host factors may be responsible for the observed differences in the distribution of cases across NHL subtypes.

Canada↗
PubMed1998

Natural choice in nonhuman primates.

In 5 experiments, 4 monkeys and 1 ape chose between 2 food sources, each held in 1 of the experimenter's hands while he stood in front of a cage. When choosing between 2 sources of the same food that differed in amount, preference for the larger amount decreased as the size of each good proportionately increased. A second finding was that subjects were indifferent between a 2-food mixture and a single food that was part of the mixture if the single food was the preferred food of the mixture, a result suggesting the less preferred food had no value. Experiment 6 replicated these effects in 4 additional monkeys. These effects may be incompatible with previous theorizing about animal choice and may reflect a cognitive difference between nonhuman primates and humans.

Animals↗
PubMed1998

Randomized placebo-controlled trial of local anaesthetic infusion in day-case inguinal hernia repair.

BACKGROUND: This study investigated the efficacy of local anaesthetic wound perfusion following day-case inguinal hernia repair. METHODS: Seventy-two patients entered a randomized controlled trial with three patient groups: group 1, pump containing bupivacaine; group 2, pump containing normal saline; and group 3, control group without a pump. All patients had a Lichtenstein hernia repair together with ilioinguinal and iliohypogastric nerve blocks and were prescribed oral analgesia. Postoperative pain was assessed over 5 days using a visual analogue scale. RESULTS: Patients who had a local anaesthetic infusion had significantly less pain than either the placebo or control groups. This was greatest during the first 48 h (day 1, P = 0.028 and 0.011 respectively; day 2, P = 0.012 and 0.037 respectively). CONCLUSION: A portable infusion pump for the delivery of local anaesthetic reduced pain after day-case inguinal hernia repair.

Adolescent↗
PubMed1998

Expression of neuronal markers in oligodendrogliomas: an immunohistochemical study.

The oligodendroglioma has been considered to be a tumour showing oligodendrocyte differentiation, but studies of the expression of oligodendrocyte markers have not conclusively demonstrated this and the pattern of differentiation of this tumour remains uncertain. Recent studies have suggested that some oligodendrogliomas may show neuronal differentiation. The aim of this study was to determine whether there was evidence of neuronal differentiation in a series of oligodendrogliomas, and, if so, to determine whether this identified a biologically or clinically distinct group. Immunohistochemistry was carried out on paraffin sections using antibodies to synaptophysin, phosphorylated and non-phosphorylated neurofilament proteins. An archival series of 32 oligodendrogliomas had been previously characterized for histological features, histological grade, Ki-67 labelling index, apoptosis index and prognosis. Six per cent of tumours showed expression of synaptophysin. Thirty-one per cent of cases showed expression of neurofilament proteins with an antibody to non-phosphorylated epitopes, but no cases were positive with antibodies to phosphorylated neurofilament epitopes. Tumours showing expression of neuronal markers did not show a difference in the distribution of histological grade or GFAP expression from those which did not express these markers, and there was no difference in labelling indices or prognosis between the two groups. In conclusion, a subset of oligodendrogliomas showed expression of neuronal lineage markers; this is discussed in relation to histogenesis and differential diagnosis. The expression of such markers did not identify a biologically or clinically distinct subgroup.

Biomarkers↗
PubMed1998

A patient's perspective on the management of peptic esophageal stricture: experience and results in 113 consecutive cases.

A retrospective analysis of 113 consecutive cases of benign esophageal stricture, all secondary to gastroesophageal reflux, 100 treated conservatively, 13 treated surgically, has been carried out in conjunction with a postal questionnaire of patients. Patients were requested to grade both their swallowing ability and the acceptability of their treatment. Of those responding to questionnaire, 88% of patients treated conservatively found their treatment acceptable or better, and 72% were left with either no or minimal restriction of diet. There was no correlation between either the total number or frequency of dilatations and the result achieved. Similarly, patient satisfaction appears largely independent of these variables. Doctors should be wary of taking recurrence of a stricture after initial dilatation as indicating a poor eventual outcome or a dissatisfied patient. There was no difference in terms of either the result or patient satisfaction between conservatively treated and surgically treated patients.

Adult↗
PubMed1998

A preliminary study of immunologic and hematologic profiles of peripheral blood from Nebraska farmers who apply pesticides to their fields.

OBJECTIVE: Laboratory studies have documented a wide range of pesticide-induced changes in the hematopoietic and lymphoreticular systems. Some of these are expressed as altered serum values, blood cell counts, and leucocyte functions. The goal of the present study was to determine whether these alterations were evident in peripheral blood of Nebraska farmers who applied pesticides to their fields. METHODS: An invitation to participate was mailed to 100 residents (70 farmers; 30 controls) of Butler County, Nebraska. All respondents (51 farmers and 21 controls) were enrolled and surveyed by written questionnaire for health status and pesticide use. Our analysis included 45 farmers and 18 controls. The farmers were divided into a high (n = 23) and a low (n = 22) pesticide use group. Statistical correlations of ten blood values with both pesticide use and age were evaluated, since pesticide use correlated with age. RESULTS: Four of the ten blood values correlated with pesticide use and age (Spearman Rho). In a multiple regression model, pesticide use (not age) proved to be a predictor of red blood cell count and hematocrit. In the same model, pesticide use was not a predictor of mean red cell volume or candida antigen-induced T-lymphocyte proliferation. Serum complement activity did not correlate with pesticide use among the farmers (n = 45) but was significantly reduced (ANOVA) in the high pesticide use group, compared to controls. CONCLUSIONS: A preliminary study of blood values in a small cohort of Nebraska farmers found no pesticide-associated effects on 1) leucocyte count, 2) antigen- and mitogen-stimulated T-cell proliferation, 3) mitogen-stimulated B-cell proliferation, and 4) concentrations of serum IgG and IgM. The study found small but statistically significant pesticide-associated effects on red blood cells and serum complement.

Adult↗
PubMed1998

Proliferation and cell death in oligodendrogliomas.

The rates of cell proliferation and of cell loss influence the growth rate of a tumour and reflect genetic changes. We studied proliferation and apoptosis in oligodendrogliomas and their relationship to progression of the tumours. Thirty-two cases of oligodendroglioma were retrieved spanning a 10-year period. The diagnosis and grade were reviewed and follow-up data obtained. Mitotic index (MI) and apoptotic index (AI) were determined from haematoxylin and eosin (H & E) stained sections. A labelling index (LI) of proliferating cells was obtained using the MIB1 antibody to the Ki-67 antigen. A further index of apoptosis was obtained using in situ end-labelling of DNA strand breaks (TUNEL index, TI). Fourteen cases were graded as II, 18 as III (1993 WHO). LI was significantly higher in grade III than in grade II tumours (P < 0.01) but the difference in apoptotic indices between grades was not significant. There was a significant (P = 0.036) positive correlation between the logarithms of TI and LI. Construction of survival curves demonstrated a significant difference in survival according to histological grade (P < 0.05). Stratification of cases by LI alone did not predict significantly different survival outcomes, and apoptotic indices did not demonstrate a relationship to survival. A positive relationship was demonstrated between proliferation and apoptosis in oligodendrogliomas. The levels of apoptosis observed indicate that this phenomenon may have an important influence on the overall rate of tumour growth.

Adolescent↗
PubMed1998

[Reproducibility and prognostic value of histopathological classifications of malignant lymphomas. Prolegomena for the 1st international classification proposed by WHO. Group of the non-Hodgkin's Malignant Lymphoma Classification Project].

Different histopathologic classifications have been used in the study of malignant lymphomas. The clinical relevance (reproducibility, prognostic value) has not been precisely studied. The "non-Hodgkin's lymphoma classification project" has been organized to study a cohort of 1,403 cases in 9 sites around the world consisting of consecutive patients seen between 1988 and 1990 in order to have a good follow-up. The reproducibility of the up-dated Kiel and the ILSG (REAL) classifications between the 5 visiting expert hematopathologists was pretty good, at least 85% for the majority of the entities. According to survival curves, the lymphomas can be stratified in 4 different groups. Comparison with the international prognostic index demonstrate that for therapeutic strategy both histopathology and index should be used. The results bring a good support to the project of the WHO to propose the first international classification of lymphomas based on both forme classifications.

Age Factors↗
PubMed1997

Pretreatment TNM staging of childhood rhabdomyosarcoma: a report of the Intergroup Rhabdomyosarcoma Study Group. Children's Cancer Study Group. Pediatric Oncology Group.

BACKGROUND: The Intergroup Rhabdomyosarcoma Study Group (IRSG) studies began in 1972 and initially used a clinicopathologic system to place patients into prognostic groups. Because of interest in the development of a pretreatment staging system for assessing the posttreatment outcomes of patients with this disease, potential staging elements were retrospectively evaluated in a subset of 505 patients who participated in IRS-II, an IRSG clinical trial. METHODS: Using the IRS-II data, a TNM pretreatment staging system was developed and used to stage prospectively the patients who were entering IRS-III, a subsequent treatment protocol of the IRSG. Failure free survival and overall survival were compared by pretreatment stage in IRS-III as a means of evaluating this TNM staging. RESULTS: The TNM staging system described the tumor (T) in terms of lesion size (< 5 cm or > or = 5 cm) instead of invasiveness, because these two features were not independent of each other. The clinical status of regional lymph nodes (N) was included in the staging system, as was the presence or absence of metastatic disease (M). The latter feature was extremely important, as expected. The anatomic site of the primary tumor also proved to be an important staging element. Classification of patients by tumor size, clinical status of regional lymph nodes, presence or absence of metastatic disease, and location of the primary tumor (at a favorable or unfavorable anatomic site) created four prognostically distinct staging categories that were relatively equal in size. In a prospective evaluation of this staging system with IRS-III patients, the pretreatment staging lost some prognostic impact. The survival of patients with smaller lesions at unfavorable anatomic sites without clinically involved lymph nodes (Stage II) was similar to that of patients with primary tumors at favorable anatomic sites (Stage I). CONCLUSIONS: A pretreatment TNM staging system for childhood rhabdomyosarcoma, developed with data from IRS-II, was not as predictive of patient outcome when applied prospectively to patients treated in the IRS-III trial. These findings could be due to differences in the management strategy used for IRS-III or the statistical variability in the model-fitting process used to develop the staging system. This demonstrates the need for continual reevaluation of staging systems as patient evaluation and treatment innovations are developed.

Child↗
PubMed1997

Recommendations for the biopsy procedure and assessment of skeletal muscle biopsies.

Muscle biopsy has a valuable diagnostic role in many neuromuscular diseases, but it is an invasive investigation that should not be undertaken lightly. Furthermore, the biopsy procedure and subsequent laboratory processing of the specimen may significantly influence the results. The following guide is designed to optimise the diagnostic information that can be obtained from muscle biopsy. It covers the whole procedure, from selection of the biopsy site and technique of biopsy, progressing through freezing of the specimen for histochemistry, and the role of immunocytochemistry and electron microscopy. Finally, the contents of a model biopsy report are considered.

Biopsy↗
PubMed1997

Doppler index perfusion in the detection of hepatic metastases secondary to gastric carcinoma.

BACKGROUND: The early detection of liver metastases in patients with gastric carcinoma is important for determining the appropriate therapy; however conventional imaging techniques are limited for detecting "occult" liver metastases. Previous studies have shown that the measurement of the Doppler perfusion index (DPI)-ratio of hepatic arterial to total liver blood flow-can detect the presence of even small hepatic tumors. In this study, we compared the measurement of DPI with computed tomography (CT) for detecting gastric liver metastases. METHODS: At presentation, 43 patients with gastric carcinoma underwent CT scanning of the liver and after 12 hours of fasting, DPI measurement was carried out using Doppler sonography. RESULTS: Both techniques detected overt liver metastases in 9 of the 43 patients. Of the 34 remaining patients with an apparently disease-free liver on the basis of CT, laparotomy, or laparoscopy, 14 subsequently develop liver metastases over a follow-up period of 4 years, 13 of which had been predicted by DPI at the time of presentation. CONCLUSION: The data suggest that the measurement of the DPI is more sensitive than a CT scan for detecting liver metastases secondary to gastric carcinoma.

Aged↗
PubMed1997

Congenital myopathy with excess of thin myofilaments.

Three unrelated young children are reported to have suffered since birth from muscle hypotonia and two of them from fatal respiratory insufficiency. Muscle tissues were found to contain large masses of thin myofilaments, immunologically identified as containing actin, but without further morphological features. These masses of thin filaments were found in different muscles at different occasions in the three children, suggesting a disease-specific morphological and possibly nosological feature all of them justifying classification as congenital myopathy with excess of actin or actin myopathy. The lesions were dissimilar to hyaline bodies in that the latter consist of granular material which is faintly positive for ATPase activity whereas the masses of thin filaments are devoid of ATPase activity. Two of our three patients also had intranuclear rods with virtually no sarcoplasmic rods suggesting the term of this congenital myopathy as actin myopathy with intranuclear rods.

Actin Cytoskeleton↗
PubMed1997

The role of examples and rules in the acquisition of a cognitive skill.

In 3 experiments, participants memorized 8 examples, each exemplifying a different rule. Participants were asked to extend these rules to new examples. They practiced applications of the rules to examples over a period of 4 days (Experiment 1) or 5 days (Experiments 2 and 3). Although these rules were bidirectional, an asymmetry gradually built up such that participants became more facile in using the rules in the practiced direction. Participants also showed an advantage when the initial study example was repeated or when test examples were repeated. It is argued that skill acquisition involves development of a complex set of strategies based on use of rules and retrieval of examples. Four overlapping stages of skill acquisition are described.

Analysis of Variance↗