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Biomedical subjects

J R Anderson

Publications and source records attributed to J R Anderson.

At least 145 records · Page 8Linked to original sources
PubMed1996

Discrimination learning and multiple reversals in young adult and older monkeys (Macaca arctoides).

Two groups of five young adult an older stumptailed macaques (Macaca arctoides) were tested on a visual discrimination task followed by a reversal upon attainment of criterion; task and reversal were repeated until 20 reversals with the same pair of objects had been completed. Both groups required more trials to learn the first reversal than the original discrimination, with no significant difference between the groups. Older monkeys tended to show more perseverative errors on early reversals, but a striking improvement in their scores across successive blocks of reversals culminated in performances virtually indistinguishable from those of the young group by the end of testing.

Age Factors↗
PubMed1996

High-dose chemotherapy followed by autologous hematopoietic rescue for Hodgkin's disease patients following first relapse after chemotherapy.

BACKGROUND: The best results of conventional-dose salvage chemotherapy for Hodgkin's disease have been reported after first relapse. We evaluated the results of high-dose chemotherapy and autologous hematopoietic rescue for Hodgkin's disease patients who had relapsed from an initial chemotherapy-induced complete remission. PATIENTS AND METHODS: Eighty-five patients received high-dose cyclophosphamide, carmustine, and etoposide (CBV) followed by autologous bone marrow or peripheral blood stem cell transplantation. RESULTS: Actuarial survival at five years was 51%, and failure-free survival was 40%. Failure-free survival at five years was 90% for patients who received no conventional-dose salvage chemotherapy prior to CBV. Failure-free survival of patients treated initially with a four-drug regimen was not significantly different than patients treated with seven/eight-drug regimens. CONCLUSION: These results appear to be better than those reported for conventional-dose salvage chemotherapy. High-dose therapy followed by autologous bone marrow or peripheral blood stem cell transplantation should be considered for any patient with relapsed Hodgkin's disease, regardless of the length of initial remission, or type of initial chemotherapy. Certain patients, especially those with minimal disease, may benefit by proceeding directly to transplantation after relapse, without first receiving conventional-dose salvage chemotherapy.

Adolescent↗
PubMed1996

Trapping oestrid parasites of reindeer: the response of Cephenemyia trompe and Hypoderma tarandi to baited traps.

At 340-360 km North of the Arctic Circle in Norway, Hypoderma tarandi (L.) and Cephenemyia trompe (Modeer) females were caught in baited traps from 10 July to 21 August. During three summers, adverse climatic conditions inhibited flight activity of these oestrids on 56-68% of the days. Flies were not caught prior to or after these dates, nor at winds above 8 m/s, temperatures below 10 degrees C, light intensities below 20,000 lux, or during periods of rain or snow. CO2-baited insect flight traps caught significantly more H.tarandi females than non-baited traps. However, neither a white reindeer hide or reindeer interdigital pheromone glands enhanced the attraction of CO2 to H.tarandi or C.trompe. Hypoderma tarandi females also were attracted to mobile people, but not to stationary individuals. There were no significant differences in the number of C.trompe or H.tarandi caught in CO2-baited traps in a birch/willow woods, on the treeless vidda (= tundra-like biome), or at woods:vida ecotone sites. Flies were caught in traps on days when the nearest reindeer herds were 25-100 km away. Significantly more H.tarandi and C.trompe were caught from 09.30 to 14.30 hours than from 14.30 to 19.30 hours; no flies were caught from 20.00 to 07.00 hours (Norwegian Standard Time = NST). Because of CO2-baited traps caught from hundreds to thousands of mosquitoes, blackflies and Culicoides midges, when climatic conditions inhibited oestrid activity, reindeer aggregations and movements attributed to insect attacks during warm sunny days may be largely in response to attacks by H.tarandi and C.trompe.

Animals↗
PubMed1996

Trapping oestrid parasites of reindeer: the relative age, fat body content and gonotrophic conditions of Cephenemyia trompe and Hypoderma tarandi females caught in baited traps.

Dissection of flies caught in northern Norway revealed that only mated, gravid females of H.tarandi (L.) and larviparous C.trompe (Modeer) were caught in host-mimicking CO2-baited traps. Trapped females had the same gonotrophic and fat body (FB) conditions as females caught on and around reindeer. Most trapped females of both species were of middle to old age, having only one-half to no FB reserves left and only a few to moderate numbers of eggs or larvae remaining. Most young females trapped also had previously oviposited or larviposited at least once, and some newly eclosed, mated females were present throughout the fly season. Based on the known location of reindeer herds, it was evident that trapped flies that had recently oviposited or larviposited had dispersed into the trapping area from 25-100 km away. Declining FB reserves sustained wild-caught C.trompe females (and in utero larvae) in the laboratory for 14 days and H.tarandi females for 18 days. Reserve FB also was depleted during long flights. Females of both species that flew for the longest times (5.1-11.7 h) on a laboratory flight mill had low FB reserves, but nearly maximum numbers of eggs or larvae. Conversely, most females that flew for less than 5 h on the light mill had little or no FB remaining, and few eggs or larvae. The large FB reserves accumulated as larvae feed in the vertebrate host enable the non-feeding adults to survive and infect their hosts even after prolonged periods of flight-inhibiting climatic conditions.

Age Factors↗
PubMed1996

Paravertebral muscles in disease of the cervical spine.

OBJECTIVES: Cervical spine disorders are common in the older population. The paravertebral muscles are essential to the support and stabilisation of the cervical spine but have been little studied. The aim was to determine whether pathological changes develop in these muscles in patients with severe cervical spine disease, which, if present, might contribute to the pathogenesis and symptomatology of their disorder. METHODS: Open biopsies of superficial and deep paravertebral muscles were obtained during the course of surgical procedures to alleviate cervical myelopathy. Most of these patients had cervical spondylosis or rheumatoid arthritis involving the cervical spine. The biopsies were compared with muscle obtained at necropsy from patients without a history of cervical spine or neuromuscular disorder. RESULTS: Muscle from both the study and control groups showed a similar range and severity of abnormalities. In several patients, grouped fibre atrophy suggested chronic partial denervation. Most biopsies showed type 1 fibre predominance and selective type 2 fibre atrophy. Ragged red fibres were a frequent finding and electron microscopy disclosed accumulations of mitochondria, a small proportion of which contained rounded, or longitudinally oriented, single osmiophilic inclusions. Fibres containing core-like areas were also frequent. These pathological features were seen with increasing severity and frequency with increasing age. CONCLUSIONS: The paravertebral cervical muscles develop pathological abnormalities with increasing age with both neurogenic and myopathic features, the pathogenesis of which is probably multifactorial. Such a muscle disorder would be expected to be accompanied by functional impairment which may contribute to the development and symptomatology of cervical spine disease with increasing age.

Aged↗
PubMed1996

Phase I/II trial of PIXY321 to enhance engraftment following autologous bone marrow transplantation for lymphoid malignancy.

PURPOSE: A phase I/II study of PIXY321 following high-dose therapy (HDT) and autologous bone marrow transplantation (ABMT) was conducted to evaluate the safety and clinical potential of this agent. PATIENTS AND METHODS: Fifty patients with Hodgkin's disease or non-Hodgkin's lymphoma (NHL) undergoing HDT and ABMT received PIXY321 post-ABMT in doses that ranged from 50 to 1,000 micrograms/m2/d either as intravenous (i.v.) or subcutaneous (SC) dosing until engraftment was reached. RESULTS: If all doses are considered together, the median time to reach an absolute neutrophil count (ANC) > or = 500/microL was 18 days and the median time to platelet transfusion independence was 21 days. At the estimated optimum dose of 750 micrograms/m2/d by SC injection once daily, the median time to reach an ANC > or = 500/microL was 15 days and the median time to platelet transfusion independence was 16 days. Historical control patients who received granulocyte-macrophage colony-stimulating factor (GM-CSF) had a median time to an ANC > or = 500/microL of 19 days and a median time to platelet independence of 26 days. CONCLUSION: The administration of PIXY321 post-ABMT was generally well tolerated and resulted in prompt engraftment in the majority of patients who underwent HDT and ABMT for lymphoid malignancies. The optimum dose and route of administration of PIXY321 suggested by this trial was 750 micrograms/m2/d by once-daily SC injection. Compared with historical control patients who received 2-hour i.v. GM-CSF, patients who received PIXY321 at 750 micrograms/m2/d by SC injection once daily had an improvement in the median days to neutrophil and platelet engraftment by 4 and 10 days, respectively.

Adult↗
PubMed1996

Single-photon emission computed tomography gallium imaging versus computed tomography: predictive value in patients undergoing high-dose chemotherapy and autologous stem-cell transplantation for non-Hodgkin's lymphoma.

PURPOSE: To evaluate the predictive value of computed tomography (CT) scanning and single-photon emission computed tomography (SPECT) gallium (Ga) scanning in the disease-free survival of patients receiving high-dose chemotherapy and autologous stem-cell transplantation for non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: One hundred forty-three patients undergoing transplant for NHL underwent CT scanning of chest, abdomen, and pelvis, and a SPECT Ga scan before transplantation and at day + 100 after transplant. The failure-free survival (FFS) by scan result was analyzed. RESULTS: In the diffuse aggressive lymphoma patients, the 1-year FFS for patients having a positive SPECT Ga scan at day + 100 was 15% compared with a 3-year FFS of 47% for those with a negative scan (P < .001). Patients with a positive CT scan at day + 100 had a 36% 3-year FFS, and those with a negative CT scan had a 39% 3-year FFS (P = not significant [NS]). An analysis of the combination of CT scan and SPECT Ga scan results at day + 100 posttransplant demonstrated a 3-year FFS of 14% if they were both abnormal; if the CT was positive and Ga was negative, the 3-year FFS was 68%; positive Ga with a negative CT was 25%; and both negative was 34% (P = .0015). For the patients with follicular NHL, those with a positive SPECT Ga at day + 100 had a 14% 1-year FFS compared with those with a negative scan, who had a 45% 3-year FFS (P < .001). In the follicular NHL patients, the 3-year FFS of those with a positive CT was 17% compared with a 64% 3-year FFS for patients with a negative CT scan (P < .001). CONCLUSION: The use of SPECT Ga scan at day + 100 posttransplant for evaluation of disease activity in patients with diffuse aggressive NHL was highly predictive of eventual outcome and was more predictive than the CT scan results. However, for patients with follicular NHL, the addition of SPECT Ga scanning to CT scanning did not add substantially to the evaluation of transplant outcome.

Adolescent↗
PubMed1996

Acute epididymitis: a work-related injury?

Occupational medicine physicians frequently are presented with requests by employers to determine the work-relatedness of medical illnesses or injuries. Occasionally, this involves a sudden onset of acute epididymitis in the male employee after strenuous activity in the workplace. Because the vast majority of acute epididymitis cases have an underlying sexually transmitted disease component, this poses a real dilemma for the consulting physician. This article discusses the etiology and pathogenesis of acute epididymitis along with its epidemiologic significance and reviews workers' compensation and its possible legal interpretation when acute epididymitis occurs at the worksite.

Acute Disease↗
PubMed1996

Cardiopulmonary function and autologous bone marrow transplantation: results and predictive value for respiratory failure and mortality. The University of Nebraska Medical Center Bone Marrow Transplantation Pulmonary Study Group.

Cardiopulmonary complications are a major cause of morbidity and mortality in patients undergoing high-dose therapy with stem cell transplant support. Since exercise tolerance testing (ETT) assesses the cardiopulmonary reserve of an individual, we hypothesized that ETT performed prior to transplant would predict respiratory failure and mortality and would be a superior predictor over resting cardiopulmonary function tests. We performed a retrospective study of 191 lymphoma patients who underwent ETT prior to transplant between 1 June 1990 and 31 December 1992 and compared the results of ETT with resting pulmonary function tests (PFT) and resting cardiac ejection fraction (EF). ETT revealed that cardiac, pulmonary and combined cardiopulmonary limitation were observed in 31, 20 and 16% of the patients, respectively, with a gas diffusion-type limitation being the most common exercise limitation. Resting PFT were abnormal in 58% of patients with a diffusion defect being the most common abnormality. Low EF was observed in 6.8% of patients. Twelve patients eventually required mechanical ventilation post-transplant with only the resting diffusion PFT predictive of this complication. There were five early deaths that were attributable to respiratory failure and neither resting nor ETT studies were predictive of these deaths. ETT and EF performed prior to transplant in lymphoma patients undergoing autologous transplant do not predict for either respiratory failure or short-term mortality. Our findings may be due to the rather low incidence of respiratory failure (6.3%) and low early mortality from cardiopulmonary complications (2.6%) seen in our patient population.

Adolescent↗
PubMed1996

Training surgeons and safeguarding patients.

Surgical trainees need exposure to a wide variety of operations and a chance to operate under supervision. At the same time there is the over-riding responsibility to do the best for our patients. Cardiac surgery is dominated by coronary bypass surgery and the tendency has been to delegate easy coronary cases to trainees and to neglect their experience in other areas. This paper is an audit of trainee exposure and supervision in a training centre. During a 20-month period, 35.2 per cent of cases were delegated; 20.6 per cent to the senior registrar and 14.6 per cent to the registrars. Senior registrars were assisted by the consultant in 19.1 per cent of their cases and registrars were assisted by more senior colleagues in 28.5 per cent of theirs. Most cases delegated to trainees were of low perioperative risk and operations were performed with commensurate low morbidity and mortality. The delegation of valve surgery was disproportionately low in comparison to overall case mix. On the basis of this study, the delegation of cases is being reviewed in the knowledge that with appropriate selection, trainees can gain valuable operative experience without compromising patient-safety.

Aged↗
PubMed1996

Molecular epidemiology of deletions and mutations of the latent membrane protein 1 oncogene of the Epstein-Barr virus in posttransplant lymphoproliferative disorders.

Latent membrane protein 1 (LMP1) is a protooncogene of the Epstein-Barr virus (EBV) that is expressed in most EBV-positive posttransplant lymphoproliferative disorders (PTLD). Small deletions in the carboxy-terminal domain of LMP1 have been recently described in Hodgkin's disease, nasopharyngeal carcinoma, and non-Hodgkin's lymphoma. We characterized the deletions and point mutations of LMP1 in 32 PTLD and 8 reactive lymphoid cases found to contain EBV by one or more methods, including LMP1 immunohistochemistry, EBV-encoded RNA in situ hybridization, LMP1 DNA amplification, or Southern blot analysis. Our goal was to study the relationship of LMP1 deletions and mutations with the PTLD morphology, clonality, EBV strain subtype, and survival of patients. We found a 30-bp deletion (Del-LMP1) in 13 of 32 (41%) PTLD cases and a similar incidence of Del-LMP1 and point mutations in 3 of 8 (38%) reactive EBV cases (rho = 0.87). The presence of the Del-LMP1 in the PTLD cases was not highly associated with a high-grade morphology or clonal immunoglobulin gene rearrangements compared with the wild-type LMP1. We found that 100% of B-strain isolates, compared with 30% of A-strain isolates, harbored the Del-LMP1. There was no significant difference in the survival of PTLD patients with or without Del-LMP1 (rho = 0.83). We conclude that the incidence of Del-LMP1 in PTLD may be reflective of the incidence of this EBV substrain in the regional population and that the Del-LMP1 sequence has no prognostic significance in PTLD.

Adolescent↗
PubMed1996

Long-term survival in advanced chronic myelogenous leukemia following bone marrow transplantation from haploidentical related donors.

From 1987 to 1991, 26 patients with CML and a median age of 31 years received allogeneic BMT from a partially mismatched related donor (PMRD) who shared at least one haplotype with the recipient. Nine patients were in accelerated phase (AP), and 11 patients were in blast crisis (BC) at the time of BMT. Patients were mismatched either in graft-versus-host or host-versus-graft directions for one antigen in 3 patients, two antigens in 14 patients, and three antigens in 9 patients. All patients were prepared with a regimen consisting of total body irradiation, etoposide, cytosine arabinoside, cyclophosphamide and methylprednisolone. All marrows were treated ex vivo with T10B91.A-31, a monoclonal antibody directed toward the alpha beta heterodimer of the CD3 receptor, and rabbit complement. Additional GVHD prophylaxis included either the anti-CD5 immunoconjugate XomaZyme-H65, cyclosporine, or both in combination with methylprednisolone. Eight patients did not have sustained engraftment. The 100-day survival was 42%. The incidence of > or = grade II acute GVHD was 29%. The incidence of chronic GVHD was 50% and was limited in all cases. The median survival at 4 years for all 26 patients was 27%. Seven patients (CP 1, AP 3, BC 3) remain in hematologic remission 1297-2241+ days after transplantation. AlloBMT from a PMRD may be considered for patients with advanced CML who lack a matched sibling or unrelated donor.

Adolescent↗
PubMed1996

Transhiatal oesophagectomy: a comparison of alternative techniques in 68 patients.

Over a 7-year period 68 patients with oesophageal carcinoma underwent transhiatal oesophagectomy, utilizing blunt dissection in 42 cases and eversion stripping in 26. The effects of the alternative techniques on mortality and morbidity have been analysed. There was no significant difference between the two techniques in terms of operative blood loss or time or the number of patients requiring post-operative ventilatory support. Stripping of the oesophagus was associated with significantly fewer cardiorespiratory complications and a shorter hospital stay. There was no significant difference in either 30-day or 3-month survival. Eversion stripping should become the preferred method of oesophageal resection once the primary tumour has been mobilized.

Bronchopneumonia↗
PubMed1996

Abnormal cerebral glucose metabolism in HIV-1 seropositive subjects with and without dementia.

UNLABELLED: This study was undertaken in order to extend our previous finding of relative basal ganglia hypermetabolism in AIDS dementia complex (ADC) and to develop clinically useful metabolic indices of CNS involvement in HIV-seropositive (HIV+) subjects. METHODS: Twenty-one HIV+ subjects (11 with AIDS) underwent FDG-PET scanning; 12 had a follow-up scan at 6 mo and 4 had a third scan at 12 mo. Forty-three age-matched heterosexual volunteers served as controls. FDG-PET scanning was performed with arterial blood sampling, and scan data were analyzed using the Scaled Subprofile Model (SSM) with principal component analysis. RESULTS: SSM/principal component analysis of the combined (HIV+ and controls) FDG-PET dataset extracted two major disease-related metabolic components: (a) a nonspecific indicator of cerebral dysfunction, which was significantly correlated with age, cerebral atrophy and ADC stage and (b) the striatum, which was heavily weighted (relatively hypermetabolic) and appeared to provide a disease-specific measure of early CNS involvement. CONCLUSION: FDG-PET scans provide quantitative measures of abnormal functional connectivity in HIV-seropositives-with or without AIDS or ADC. These measures, which are robust across centers with respect to instrumentation, scanning technique and disease severity, appear to track the progression of CNS involvement in patients with subclinical neurologic or neuropsychologic dysfunction.

AIDS Dementia Complex↗
PubMed1996

Prospective comparison of laparoscopy, ultrasonography and computed tomography in the staging of gastric cancer.

A total of 103 consecutive patients with gastric adenocarcinoma was assessed for intra-abdominal spread of malignancy using ultrasonography, computed tomography (CT) and laparoscopy under general anaesthesia. Histologically proven metastases were to the liver in 27 patients, lymph nodes in 49 and directly to peritoneum in 13. All modalities showed a high specificity (92-100 per cent) for each type of metastasis. Laparoscopy was more sensitive in detecting hepatic, nodal and peritoneal metastases; the relative performance of laparoscopy was best with regard to hepatic metastases. Ultrasonography and CT were particularly poor at detecting nodal and peritoneal metastases. There was no significant morbidity and no mortality associated with laparoscopy, which was more accurate in preoperative staging of gastric cancer than ultrasonography or CT.

Adenocarcinoma↗
PubMed1995

Prognostic value of cellular proliferation and histologic grade in follicular lymphoma.

The clinical usefulness of histologic grading in follicular lymphoma (FL) is controversial and is further compromised by the subjective nature and poor reproducibility of most systems in current use. Therefore, we decided to objectively evaluate the importance of cellular proliferation in FL, along with the current grading systems. We studied 106 patients with FL who were uniformly staged and aggressively treated. A proliferative index (PI) was determined quantitatively using an automated image analyzer and a new Ki-67 antibody that stains archival paraffin tissues. The cases were also subclassified according to the Berard, Rappaport, Luke-Collins, and Jaffe methods, and survival analysis was performed. Patients with a low PI (< 40%) had a significantly longer overall survival (OS) than those with a high PI (> or = 40%), but the PI did not predict failure-free survival (FFS). The mean PI correlated well with the subgroups in each of the various classifications. All four of the classification methods were predictive of OS, but only the Berard method appeared to predict FFS and suggest that a proportion of patients with FL may be curable. In multivariate analysis, histologic classification was the only independent predictor of OS (Berard method: relative risk, 3.1) and the International Prognostic Index was the only independent predictor of FFS (relative risk, 2.3). We conclude that the Berard method for grading of FL is clinically useful and, along with the International Prognostic Index, should be included in future clinical studies of FL. The measurement of cellular proliferation does not appear to add additional useful information in FL.

Adult↗