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Biomedical subjects

D Jones

Publications and source records attributed to D Jones.

At least 505 records · Page 28Linked to original sources
PubMed1992

A comparison of FDG PET and IQNB SPECT in normal subjects and in patients with dementia.

Prior studies of patients with dementia have found similar qualitative patterns of cerebral glucose utilization with [18F]2-fluoro-2-deoxyglucose (FDG) PET and of putative muscarinic receptor activity with [123I]3-quinuclidinyl-4-iodobenzilate (IQNB). This raised doubts about whether receptor binding determines IQNB distribution and whether clinical information in IQNB scans is unique. To compare the methods directly, 4 normal volunteers and 7 patients with dementia underwent FDG PET and high-resolution IQNB SPECT scans. In normal subjects, relative regional activity from the paired scans was only weakly correlated (r = 0.29). Some regions (e.g., thalamus, frontal cortex) showed a clear disassociation of activity. In demented patients, IQNB scans tended to show larger defects than FDG scans, although one focal defect appeared only with PET. Results suggest that IQNB SPECT data are not primarily related to general physiological activity or regional cerebral blood flow and are not explained by attenuation or volume-averaging artifacts. Further studies should investigate whether IQNB scanning is a more sensitive in vivo measure of the extent of Alzheimer's disease than is FDG PET.

Adult↗
PubMed1992

The TAPS project. 6: New long-stay psychiatric patients and social deprivation.

The clinical and social characteristics of new long-stay (NLS) patients at Friern and Claybury hospitals are described, together with their accumulation rates within health districts in northeast London, and the associations between accumulation rates and social deprivation. There is a fourfold variation between local districts in annual accumulation rates of NLS patients (between 2.5 and 11 per 100,000 population); 0.55 of this variation is accounted for by the Jarman scores of social deprivation, and 0.81 by local rates of unemployment. Other recent British studies support this finding that measures of social deprivation can statistically explain a large proportion of the variation in treated rates of psychiatric morbidity, and may be useful in predicting needs for psychiatric services.

Adult↗
PubMed1992

Vocal evaluation of thyroplastic surgery in the treatment of unilateral vocal fold paralysis.

Vocal function was assessed in 15 patients who received thyroplasty type I for the rehabilitation of unilateral vocal fold paralysis. The function was assessed by perceptual evaluation, voice intensity and frequency range profiles, and questionnaire. Goals of the study were to evaluate the efficacy of thyroplasty in improving the voice, to compare postoperative thyroplasty voices to normal voices, and to correlate objective measurements to the results of the questionnaire regarding satisfaction with the voice. Perceptual evaluations were performed by randomizing normal and thyroplasty voices on a recording tape. The voices on the tape were then rated by independent, blinded, trained listeners. The perceptual qualities of pitch, intonation, and loudness were not statistically different than normals; however, voice qualities of strain, breathiness, hoarseness, harshness, and unsteadiness were different than normals. Mean frequency range and mean intensity range were moderately to severely reduced from normals with a wide variation being present in the results. The correlation between the higher threshold phonation pressures and decreased intensity ranges found in some patients is discussed. Questionnaire results indicated that a high degree of satisfaction with the surgery was present (92%). Extreme or general satisfaction with voice was present in 73%. The most difficult voicing was experienced at work, with 25% needing to adjust their employment to accommodate their voice abilities. These results indicate that thyroplasty type I is effective in partially rehabilitating unilateral voice fold paralysis. Voice function is still not normal, probably in part due to the underlying disease.

Adolescent↗
PubMed1992

Cardiovascular risk factors in Native American children.

Information concerning cardiovascular disease risk factors in Native American children is limited. In adult Native American populations, cardiovascular disease risk factors of non-insulin dependent diabetes mellitus, obesity, and cigarette smoking are prevalent, and recent reports indicate mortality caused by cardiovascular disease has dramatically increased. In a screening program at the Onondaga Nation School, six cardiovascular disease risk factors were evaluated. Of 95 school children, 55 representing 39 interrelated families, participated. Family histories were positive for diabetes mellitus in 72%, for cardiovascular disease in 54%, and for passive smoking in 90% of families. Physical examinations of the children revealed obesity (weight/height greater than 90th percentile) in 42% and hypertension (systolic or diastolic blood pressure/height greater than 95th percentile) in 22%. Fingerstick cholesterol levels (Reflotron system) were greater than 170 mg/dL in 25%. Overall, 85% of participants had three or more risk factors for cardiovascular disease. The study results indicate that Onondaga Native American children are at significant risk for cardiovascular disease; programs for identification and modification of cardiovascular disease risk factors are urgently needed.

Adolescent↗
PubMed1992

Diagnosis of human immunodeficiency virus infection by enzyme-linked immunospot assays in a prospectively followed cohort of infants of human immunodeficiency virus-seropositive women.

The enzyme-linked immunospot (ELISPOT), a method for quantifying specific and total antibody-secreting cells, was used for the diagnosis of human immunodeficiency virus (HIV) infection in a prospectively followed cohort of infants born to HIV-infected women. From July 1, 1987, to June 1, 1990, 127 infants with known HIV infection status were studied. Seventeen of 22 HIV-infected infants had specific HIV-specific antibody-secreting cells (ASC). Among the infected infants rates of ASC positivity increased during the first year of life, from 25% in the first 5 days of life to 78% after 6 months. Two of the five ASC-negative infected infants were further characterized as hypo- or dysgammaglobulinemic by an adjunct ELISPOT assay for total immunoglobulin-secreting cells. Excluding hypo- or dysgammaglobulinemic infants from the analysis, the rate of ASC positivity among infected infants was 85% (17 of 20) after the age of 6 months. None of the 95 uninfected infants had a positive ELISPOT assay, including 55 who were tested in the first 3 months of life. Thus in this series the specificity was 100%. ELISPOT methodology can be a useful technique for the diagnosis of HIV infection in infants of HIV-seropositive mothers.

Female↗
PubMed1991

Antitumor activity of Fab' and IgG-anti-CD22 immunotoxins in disseminated human B lymphoma grown in mice with severe combined immunodeficiency disease: effect on tumor cells in extranodal sites.

The antitumor effects of two anti-CD22 ricin A chain-containing immunotoxin (IT) constructs were compared in mice with severe combined immunodeficiency disease with human Daudi cell tumors (SCID-Daudi mice). SCID-Daudi mice develop disseminated lymphoma that clinically resembles African Burkitt's lymphoma, i.e., extranodal disease including infiltration of the vertebral column and spinal canal. In the absence of treatment, the mean survival time of SCID-Daudi mice was 45.9 +/- 4.3 days. The mice was given injections of a dose of IT equal to 40% of the 50% lethal dose. The ITs consisted of either IgG or Fab' fragments of mouse anti-CD22 antibody coupled to deglycosylated ricin A chain (dgA). Both ITs were potent and specific and inhibited protein synthesis in Daudi cells in vitro by 50% at concentrations of 1.2 x 10(-12) (IgG-dgA) and 1.3 x 10(-11) M (Fab'-dgA). When administered to mice beginning 1 day after inoculation with tumor cells, both ITs extended the mean survival time, to 87.2 +/- 18.9 days (IgG-dgA) or 57.9 +/- 3.8 days (Fab'-dgA). The latter represented the killing of 2 logs of Daudi cells, and the former 4 logs. IgG antibody alone killed 1 log of tumor cells. The IgG-dgA had an antitumor effect even when administered 20-23 days after tumor inoculation. Gross and histological examinations of IT-treated tumor-bearing mice showed a marked decrease in the number and size of neoplastic foci in both lymphoid organs and extranodal sites.

Animals↗
PubMed1991

Regulatory mediators in the venom of Chelonus sp.: their biosynthesis and subsequent processing in homologous and heterologous systems.

Following titration of the contents of the venom gland reservoir, the rate of biosynthesis of venom proteins was sufficiently rapid over the next 6-24 hrs to restore their titer to the level initially synthesized during early adulthood. There was no evidence of processing of smaller molecular weight components from much larger forms. Although most proteins were stable in young host embryos, two specific processing products of a 32.5 kDa venom protein were found in such hosts. The natural injection of venom proteins into either very old embryos or young embryos subsequently held at 4 degrees C for six days resulted in rapid degradation to biologically inactive forms. These data are the first report of direct examination of the biosynthesis of wasp venom proteins and the first analysis of the processing of specific hymenopteran venom proteins in target tissues.

Animals↗
PubMed1991

Segmental spinal fixation of a thoracic vertebral fracture in an adult chimpanzee.

Accidental trauma associated with an epileptic convulsion in a 10-year-old, male chimpanzee (Pan troglodytes) resulted in incomplete paraplegia from fracture and subluxation of T4. Dorsal laminectomy and segmental spinal fixation were used in treatment. The segmental spinal fixation consisted of sublaminar wires attached to a contoured 316L stainless steel U-rod. The chimpanzee recovered sufficient function to allow reintroduction into the chimpanzee colony at a zoological park during the 12 months after surgery and continues to do well 24 months after surgery.

Animals↗
PubMed1991

Human neuroblastoma cells treated with aluminium express an epitope associated with Alzheimer's disease neurofibrillary tangles.

A number of studies have implicated aluminium as a possible factor in the pathogenesis of Alzheimer's disease (AD). Following an examination of the uptake of aluminium by human neuroblastoma cells in culture, treated with a range of concentrations of aluminium complexed with ethylene-diaminetetra-acetic acid (EDTA), we have now carried out an immunocytochemical study. Using an antibody to phosphorylated tau protein, which reacts specifically with AD neurofibrillary tangles (NFT), we have found that after treatment periods of 16 days to 8 weeks with aluminium-EDTA, the cells show positive staining with this antibody. No such reaction was detected in cells grown in medium alone, nor in aluminium-EDTA-treated cells subjected to the same immunocytochemical procedure but without added primary antibody. Cells grown in medium plus EDTA, which contains a low level of aluminium contamination, showed a slight reaction. Our system may provide a suitable model for studying the early changes which lead to NFT formation.

Aluminum↗
PubMed1991

In vitro and in vivo assessment of the bioavailability of potassium from a potassium tartrate tablet.

The bioavailability of potassium from orally administered potassium tartrate was evaluated in 20 normal subjects under metabolic balance conditions. Subjects were given 34 mmol potassium (5 tablets of Cal-K) as a divided dose on each of 2 consecutive days. Urinary excretion of potassium, as determined from 24-h urinary collections on the 3 days preceding dosage totalled 192.6 +/- 50.9 mmol (mean +/- S.D., n = 20). It increased significantly (p less than 0.05) to 258.7 +/- 54.2 mmol for the 2 days of dosage and the following day. The difference of 66.1 mmol representing absorbed potassium was close to the 68 mmol potassium given and indicated a bioavailability of potassium in excess of 97 per cent; after correction for creatinine excretion, potassium recovery rose to 99.9 per cent. The dissolution characteristics of the Cal-K tablets were also determined. After dissolution in simulated gastric juice (pH 1.2), 84.4 +/- 10.6 per cent (mean +/- S.D., 6 experiments) was dissolved; after adjustment to pH 7.3, dissolved potassium increased to 91.3 +/- 8.5 per cent. No precipitation or residue formed as a result of the pH change. Both sets of results indicate that potassium from these potassium tartrate tablets is in a highly bioavailable form.

Adult↗
PubMed1991

POSSUM: a scoring system for surgical audit.

POSSUM, a Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity, is described. This system has been devised from both a retrospective and prospective analysis and the present paper attempts to validate it prospectively. Logistic regression analysis yielded statistically significant equations for both mortality and morbidity (P less than 0.001). When displayed graphically zones of increasing morbidity and mortality rates could be defined which could be of value in surgical audit. The scoring system produced assessments for morbidity and mortality rates which did not significantly differ from observed rates.

Aged↗
PubMed1991

Acute motor neuropathy with antibodies to GM1 ganglioside.

We describe a 52-year-old man who had an acute-onset purely motor neuropathy fulfilling the diagnostic criteria for the Guillain-Barré syndrome, in whom virtually complete spontaneous recovery occurred by 1 year, and in whom high titres of polyclonal serum antibody to GM1, GD1b, asialo-GM1 and lacto-N-tetraose were detected. The titre of IgM antibody to GM1 fell during the course of the disease with a concomitant rise in the IgG titre. This case adds to the widening spectrum of disease associated with anti-GM1 antibodies and provides further evidence for a relationship between anti-GM1 antibodies and motor system disease.

Acute Disease↗
PubMed1991

Neurotoxic envenoming by an immigrant spider (Steatoda nobilis) in southern England.

A young woman was bitten on the shoulder by a female Steatoda nobilis spider, in Worthing on the south coast of England. She noticed intense radiating pain, local sweating (indicating parasympathetic stimulation) and feverishness. This immigrant species from the Canary Islands has established itself along the south coast of England in recent years. Like the related Mediterranean species S. paykulliana, S. nobilis may be of medical importance and deserves further study.

Adult↗