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Biomedical subjects

J Simpson

Publications and source records attributed to J Simpson.

At least 235 records · Page 13Linked to original sources
PubMed1989

Cholinergic enzymes in the spinal cord in Alzheimer-type dementia.

Choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) were measured in anterior and posterior grey matter of the lumbar spinal cord and in temporal and frontal cortex from six cases of Alzheimer-type dementia (ATD), one case of Down's syndrome, three cases of schizophrenia (SZ) and six controls. Compared with control and SZ values, ChAT and AChE were reduced in ATD cerebral cortex. ChAT was reduced, and AChE unaltered, in ATD spinal cord. Decreased cord ChAT may be related to electrophysiological abnormalities which have been reported in motor nerves of patients with Alzheimer's disease.

Acetylcholinesterase↗
PubMed1989

Studies concerning the effect of external irradiation on localization of radiolabeled monoclonal antibody B72.3 to human colon carcinoma xenografts.

Recent studies in animal models involving antibody tumor targeting of hepatoma and melanoma and clinical trials involving hepatoma patients have suggested that preirradiation of tumors may enhance antibody tumor targeting. These reports led us to study the effect of external irradiation on monoclonal antibody (MAb) targeting of human carcinomas; as a model system, we used MAb B72.3 and the LS-174T human colon carcinoma xenograft in athymic mice. LS-174T tumors exposed to 300 cGy grew to approximately 93% the size of non-irradiated tumors, while those exposed to 600, 900, or 2,000 cGy were approximately 41% the size of control tumors. Splitting the 900 cGy into three 300-cGy fractions yielded a two-fold lower tumor volume compared with a single 900-cGy fraction. Histochemical evaluation of the carcinomas revealed a decrease in the number of mitoses per high power field consistent with early effects of radiation exposure. Using the avidin-biotin complex immunoperoxidase technique, carcinomas were assayed for expression of the tumor associated glycoprotein (TAG)-72, the high-molecular-weight mucin detected by MAb B72.3. No discernable variation was observed in the staining intensity among tumors in both the control and radiation treated group; that is, differences among tumors within each group were compatible with the known heterogeneous expression of TAG-72. Exposure of carcinomas to 300 or 900 cGy in a single fraction or 900 cGy split in three 300-cGy fractions did not yield a consistent or substantial enhanced localization of radiolabeled MAb B72.3 IgG or F(ab')2 to tumors. A 1.5-fold augmentation of MAb binding to tumors was observed in preirradiated mice; however, these results were not statistically significant. Inherent differences in tumors such as cell type of origin, size, spatial configuration, extent of vascularization and volume of interstitial space may contribute to variability of the effect of preirradiation of tumors on antibody binding. Our results suggest that consistent augmentation of radiolabeled antibody localization to tumors is not a universal phenomenon.

Animals↗
PubMed1989

Union election activity in the hospital industry.

In the past five years, there has been a dramatic decrease in the number of representation elections in the hospital industry. Once a union is in place, however, decertification is less likely to occur than in other industries.

Collective Bargaining↗
PubMed1989

A large multicentre, parallel group, double-blind study comparing tenoxicam and piroxicam in the treatment of osteoarthritis and rheumatoid arthritis.

A total of 1,328 patients with osteoarthritis or rheumatoid arthritis were entered into this double-blind, parallel group study of tenoxicam and piroxicam. The patient populations were well matched. An improvement was seen in pain on moving and at night in both groups and in both indications. Stiffness was also improved by both drugs, being most marked in the rheumatoid arthritis group. The primary efficacy variable was global assessment, and this showed tenoxicam to have slightly greater effect in osteoarthritis and the reverse in rheumatoid arthritis. There were no statistically significant differences in any of these findings. There were no significant differences in tolerance ratings, although the more serious gastrointestinal events occurred in the piroxicam group.

Adult↗
PubMed1988

An antiserum to the C-terminus of the Alzheimer amyloid precursor recognizes a soluble 70 kDa protein.

A rabbit antiserum to the C-terminus of the putative brain amyloid precursor was used to probe Western blots of tissue proteins separated by SDS-PAGE. The antiserum specifically labelled a protein of approx. 70 kDa in the Tris buffer-soluble fraction of brain samples from rat, Alzheimer subjects, cases of young and old Down's syndrome, and age-matched controls. The 70 kDa protein was present in low concentrations in human liver and kidney, and was undetectable in human skeletal muscle. The 70 kDa protein may be a metabolite of the amyloid precursor.

Adult↗
PubMed1988

Cytologic diagnosis of papillary carcinoma of the breast in needle aspirates.

Eleven cases of rare papillary carcinoma of the breast diagnosed by fine-needle aspiration cytology (FNAC) are reported. Five of these were pure papillary carcinomas and six were mixed papillary and ductal, lobular, or mucinous carcinomas. In each case, cytological material was collected by washing the needle and syringe contents into 30% alcohol in saline, and the Gelman cytosieve method was used for the cytological preparations. In this article, the cytological features of these tumors are described, including the presence of single papillae and papillary clusters, tall columnar cells, diathesis of blood with hemosiderin-laden macrophages, naked nuclei, and high cell recovery.

Adenocarcinoma, Mucinous↗
PubMed1988

Fine-needle aspiration cytology of breast: its impact on surgical practice with an emphasis on the diagnosis of breast abnormalities in young women.

Fine-needle aspiration cytology (FNAC) of the breast is a minimally invasive yet maximally diagnostic method, often precluding the need of an open biopsy. In young women, in whom breast cancer is a rare disorder, it is also important that carcinoma is recognized without delay so that an appropriate plan of management can be adopted. In this study, we reviewed our experience in a total of 3,226 needle aspirates of breast with particular emphasis on the diagnosis of carcinoma in women under the age of 30.

Adult↗
PubMed1988

Comparison of monoclonal antibodies for the detection of occult breast carcinoma metastases in bone marrow.

Twenty percent (n = 6) of Stage III or IV breast cancer patients (n = 30) had bone marrow metastases detected in bilateral bone marrow biopsy/aspiration preparations using standard histologic preparations. Each metastasis was also detected by four separate monoclonal antibodies (MAbs) which recognize breast carcinoma associated antigens (DF3, anti-EMA, HMFG-2, and CAM5.2). These MAbs were then utilized to stain other bone marrow preparations (n = 81) to determine their utility for the detection of micrometastatic breast carcinoma. MAbs HMFG-2, anti-EMA, and DF3 were each strongly reactive with bone marrows containing histologically-evident metastatic breast carcinoma (18/18). These anti-epithelial membrane antigen MAbs, however, were also reactive with rare plasma cells and immature cells (as well as cell clusters) in some of the control bone marrow samples tested, including those from normal patients and patients with hematologic disorders. They also reacted with some of the preparations from patients with leukemia and lymphoma, and with uninvolved marrows from patients with non-epithelial malignancies. The anti-keratin MAb CAM5.2, in contrast, reacted with 83% (15/18) breast cancer metastases and failed to stain any cells in the various categories of control marrow preparations. These data suggested that MAb CAM5.2 might be utilized to immunohistochemically differentiate micrometastatic breast carcinoma from immature myeloid or erythroid elements. Each MAb was then reacted with histologically uninvolved marrow preparations from the remaining 24 of 30 breast cancer patients in an attempt to identify occult breast carcinoma metastases. While MAbs HMFG-2, DF3, and anti-EMA demonstrated reactive cells in some of these marrows, this reactivity was similar to that seen with control preparations. MAb CAM5.2, in contrast, was negative with all specimens. These data suggest that MAb CAM5.2 may be a useful immunologic probe for the detection and confirmation of metastatic breast carcinoma in bone marrow, while more caution must be employed in the interpretation of results obtained using MAbs anti-EMA, DF3, and HMFG-2.

Adolescent↗
PubMed1988

Place navigation in rats is impaired by lesions of medial septum and diagonal band but not nucleus basalis magnocellularis.

The role of forebrain cholinergic projections in place navigation learning was assessed in two experiments. Following surgery, rats were required to learn the spatial location of an underwater platform on the basis of distal room cues. Bilateral injections of ibotenic acid into the nucleus basalis magnocellularis depleted choline acetyltransferase (ChAT) from the anterior and temporoparietal cortex but not the hippocampus. Separate histological studies confirmed the accuracy of the lesions and demonstrated a marked loss of cortical acetylcholinesterase. These rats subsequently showed no deficits in spatial learning or memory. In a second experiment, bilateral lesions of the vertical limb of the diagonal band of Broca and medial septum depleted ChAT from the hippocampus and posterior cortex but not the anterior cortex. Histological studies confirmed the accuracy of the lesion and showed a pronounced loss of acetylcholinesterase from the hippocampus. These rats were deficient in spatial learning and showed reduced spatial bias during transfer tests. The data are discussed in the light of the hypothesis that the cholinergic innervation of the hippocampus plays a key role in spatial reference memory processes involved in place navigation.

Animals↗
PubMed1988

Evaluation of a computerised test for the assessment of peripheral vascular disease.

This paper reports a study carried out in 200 patients to assess the effectiveness of a clinical vascular laboratory in the routine assessment of peripheral vascular disease (PVD) of the lower limb. Laboratory assessments involved a computer based hierarchical testing system incorporating pedal pressure indices, maximum walking distances and principal component analysis of the common femoral artery blood velocity waveform. The study fell into two parts. In the first, the laboratory assessments of 100 patients referred six years ago were compared retrospectively with their eventual clinical outcome. In this comparison, the laboratory provided a "diagnosis" which was 79% correct. In the second, a double blind prospective study was carried out in 100 patients to compare the vascular laboratory "diagnosis" with the diagnosis and prognosis of a skilled clinician, the outcome being compared one year after the initial assessment. In this study the laboratory proved to be correct in 78% of cases, the clinician in 70%. With a slightly modified computer protocol for the non vascular diagnosis, the computer would have been correct in 85% of cases. This test provides a quantitative and objective assessment of PVD which can assist in the patient's clinical diagnosis and management.

Diabetic Angiopathies↗
PubMed1988

Research note: recurrent headaches and stomachaches in preschool children.

Data are presented on headaches and stomachaches in a sample of 189 3-year-old children obtained as part of community based study. These data provide a partial replication of an earlier study on a separate sample of children [Zuckerman, B., Stevenson, J. and Bailey, V. (1987). Stomachaches and headaches in a community sample of preschool children. Pediatrics, 79, 677-682]. The results supported the previous findings of a link between family factors and recurrent stomachache, and a less strong association with headaches. The conclusions reinforce the notion that these two somatic symptoms should be considered separately in preschool children.

Child Development↗