Biomedical subjects
Publications and source records attributed to L Evans.
Two patients, who were receiving therapy with mianserin for depressive disorders, developed signs of disturbed cardiac function which resolved after mianserin therapy was discontinued. One of the patients also developed hypokalaemia which was probably caused by the drug. It is felt that these side effects warrant further research.
Peripheral blood lymphocytes (PBL) from genital herpes simplex virus type 2 (HSV-2) patients were transformed with Epstein-Barr virus. Using conditions optimized for successful transformation, two lymphoblastoid cell lines (LCL) have been established, which secrete immunoglobulin G (IgG) to HSV. These results suggest that PBL from patients suffering recurrent herpes virus infections can be used to establish LCL secreting HSV antigen specific human immunoglobulins.
Diabetic retinopathy is one of the leading causes of blindness in the United States today. Because early treatment of proliferative retinopathy offers the best chance for visual salvation, there is an essential need for methods of identifying eyes at high risk. Recent research has shown that subclinical leakage from retinal blood vessels is one of the earliest signs of retinopathy. The feasibility of using radionuclide techniques to quantitate blood-retinal barrier disruption is demonstrated by a study in which 23 diabetics and 7 nondiabetics were imaged with an Anger camera in the anterior Waters projection at 2 hours after the administration of Tc-99m DTPA. In the digitized images, regions of interest were placed over each orbit and over one of the cerebral hemispheres. Orbital counts were then compared to cerebral counts on a per pixel basis. Eye to brain ratios were found to be lowest for nondiabetics and highest for patients with proliferative retinopathy. Additionally, the dynamic analysis of the same radiopharmaceutical may allow investigators to further study the pathophysiology of the diabetic eye.
Small intestinal permeability to horseradish peroxidase (HRP) was assessed in jejunal biopsies of malnourished children. Clinical examination, intestinal function (D-Xylose test), and the histological appearance of the mucosa were assessed in 14 children during the malnutrition phase and in eight children after 3 months of nutritional rehabilitation. Macromolecular permeability was evaluated by measuring transepithelial HRP fluxes from mucosa to serosa (JHRPms) using Ussing chambers. Intact HRP transport, i.e., nondegraded protein transport, was measured by enzyme assay, and tritiated HRP was concomitantly used to measure intact and degraded HRP fluxes (J[3H]HRPms). Electrical parameters (short-circuit current, potential difference, and ionic conductance) were also recorded. Transepithelial HRP fluxes were significantly higher during malnutrition (JHRPms = 8.85 +/- 1.44; J[3H]HRPms = 77.11 +/- 10.66 pmol X h-1 X cm-2) than in the same children after 3 months of nutritional rehabilitation (JHRPms = 2.94 +/- 1.10; J[3H]HRPms = 22.93 +/- 8.15 pmol X h-1 X cm-2). The total ionic conductance, which is an index of paracellular permeability, did not change significantly. Calculated intratissue degradation of the protein did not appear to alter during malnutrition. These results point to a clinical situation in which malnutrition with diarrhea in children is associated with increased intestinal permeability to macromolecules by a mechanism not related to any paracellular leak of the protein, but rather to increased transcellular absorption.
A new strain of Friend recombinant mink cell focus-inducing retrovirus, FMCF -1-E, was found to induce leukemias in NFS and IRW mice. Although the isolate was obtained from a stock of FMCF -1 ( Troxler et al., J. Exp. Med. 148:639-653, 1978), FMCF -1-E was distinguishable from FMCF -1 by oligonucleotide fingerprinting and antigenic analysis, using monoclonal antibodies. These analyses suggested that FMCF -1-E is a distinct FMCF isolate rather than a simple variant of FMCF -1. After neonatal inoculation, the latency for leukemia induction was 3 to 8 months. A similar long latency was also seen when Friend murine leukemia virus 57 was inoculated into adult (6-week-old) IRW mice. However, sequential inoculation of FMCF -1-E at birth followed by Friend murine leukemia 57 at 6 weeks of age led to a shortened latency period (2.5 to 4 months). Only neonatal inoculation of Friend murine leukemia virus 57 was able to induce a more rapid appearance of leukemia. The leukemia cell type in the majority of cases, regardless of virus inoculation protocol, was erythroid, but occasional myeloid, lymphoid, and mixed leukemias were also observed. In contrast to NFS and IRW mice, BALB/c mice were resistant to leukemia induction by FMCF -1-E and also showed some transient resistance to leukemia induction by Friend murine leukemia virus 57.
The tricyclic antidepressants and the monoamine oxidase inhibitors have been shown to be effective in the treatment of some patients with phobic and panic disorders. To explain this action it has been suggested that a number of these patients may have an atypical biological depression. In an attempt to test this hypothesis we used the dexamethasone suppression test (DST), which has been proposed as a state dependent biological marker of depression. We compared the non-suppression rate of agoraphobic patients suffering panic attacks with controls and with patients suffering major depression. Twenty-nine per cent of the agoraphobics showed non-suppression compared with 12% of the control group and 64% of the depressives.
Sixteen mouse and rat monoclonal antibodies reactive with gag or env proteins of Friend murine leukemia virus (F-MuLV) or recombinant MCF viruses related to F-MuLV were derived. Specificity of these was determined by immunofluorescence, immunoprecipitation, and reactivity with viral proteins blotted onto nitrocellulose paper. Seven antibodies reacted with envelope protein antigens of certain nonecotropic viruses only. Nine antibodies reacted with both ecotropic and nonecotropic viruses. Of this latter group, three were antienvelope, four were anti-p15, one was anti-p12, and one was anti-p30 in specificity. When tested as a panel against 10 strains of F-MuLV, these antibodies could distinguish seven different antigenic patterns. However, all 10 strains retained reactivity for three anti-gp70 antibodies uniquely specific for Friend and Rauscher MuLVs. Our antibody panel could also identify MCF viruses isolated from mice neonatally inoculated with F-MuLV as recombinants related to a particular F-MuLV strain based on identity of p15 gag antigenic profiles. However, recombinant viruses lacked several envelope antigens always associated with F-MuLV and instead had new envelope reactivities. These anti-MCF monoclonal antibodies detected no shared envelope antigens between MCF and xenotropic viruses isolated from mice inoculated with F-MuLV, however many of them did react with MCF viruses derived from AKR mice and NFS mice congenic for endogenous ecotropic virus loci.
An ELISA system, based on urease activity was used for the detection and titration of IgG to the immediate early AG-4 antigen in sera from HSV-2 patients. It detected low levels of IgG to the AG-4 antigen in 32% of patients' sera known to contain complement fixing antibody to the antigen. Furthermore, the sensitivity of the ELISA system was 2- to 10-fold higher than the complement-fixation system depending on when the sera was taken from the HSV-2 patients. The system also allowed the easy detection and quantitation of AG-4 antigen production when various HSV-1 X HSV-2 intertypic recombinant viruses were used to infect BHK-21 cells.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Non-compliance with drug treatment is widespread. When patients are given medication by their doctors, nearly half do not take the drug or do not take it as prescribed, and most will stop the treatment as soon as they are feeling better. A major problem in identifying the non-compliant patient is the unreliability of many of the measures used for assessing compliance. There are few social and demographic characteristics associated with non-compliance. The type of disease, also, generally has little influence on the level of compliance. Psychological factors such as the patients' levels of anxiety, motivation to recover, attitudes towards their illness, the drug and the doctor, as well as the attitudes and beliefs of significant others in their environment do influence the patients' levels of compliance. Many of the factors that are related to non-compliance with drug regimens are within the control of health care professionals. Contrary to the beliefs of many doctors, studies do not support the view that drug non-compliance is a deviant form of behaviour influenced by patient characteristics.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Seven patients who were diagnosed as suffering from phobic anxiety were treated with a new antidepressant which causes relatively selective inhibition of serotonin uptake. This compounds, zimelidine, was given for five weeks in doses of up to 300 mg per day. One patient dropped out of the study. Of the remaining six patients all but one made an improvement, which in most cases is thought to have been a drug effect. One patient relapsed some months following treatment and responded again to treatment with zimelidine having failed to respond to other psychotropic drugs.
Three groups of 10 subjects were exposed to intermittent bursts of loud noise. Two groups attempted bi-directional cardiac control immediately prior to the noise bursts, one with the aid of continuous heart-rate biofeedback and one without. The third group did not attempt heart-rate control but instead received false feedback that heart rate was either increasing or decreasing prior to the noise bursts. Only the biofeedback-assisted group demonstrated reliably different cardiac changes during attempted heart-rate increase and decrease. The heart rates of the false-feedback subjects were unaffected by the direction of change signalled by the biofeedback display. However, a significant differential effect on subjects' ratings of the noise bursts, in terms of loudness and unpleasantness, was apparent only in the false-feedback group. Skin conductance responses showed no such effect in any of the three groups. The results are most readily accounted for in terms of attribution theory.