Biomedical subjects
Publications and source records attributed to A Davis.
A group of psychiatric in-patients significantly over-estimated the intensity of their depression when asked to recollect how depressed they had been one week earlier. The initial level of depression affected the accuracy of recall. Unexpectedly, patients who were more depressed initially had more accurate recall, particularly for biological and symptomatically negative items of the Zung Self-Rating Depression Scale.
The West Midlands Regional Children's Tumour Registry collects detailed information on all cases of childhood cancer in the West Midlands Health Authority Region (WMHAR). The distribution by electoral ward of all cases diagnosed in the WMHAR between 1980 and 1984 has been determined. Analysis has also been performed for leukaemias/non-Hodgkin's lymphomas alone. We suggest that this latter grouping should be universally employed, owing to the difficulty of accurately separating out cases of leukaemia. Both spatial analyses showed several wards with significantly excessive rates on the basis of their cumulative Poison probability. Observed/expected ratios of 3-35 were seen for cases in significant wards, which are similar to the ratios seen in analysis of incidence around nuclear installations. However, further detailed consideration of these individual significance levels in the light of the number of statistically significant wards which would occur by chance alone, due to the multiple use of the test, accounted completely for the number of wards obtained in each of the groups considered. Thus, apparent 'clustering' of cases could be mere statistical artefact. In the WMHAR, therefore, using the technique of probability mapping, no true spatial pattern of incidence was found, other than that which would occur by chance alone. This, in a large area without nuclear installations and an even mix of rural and industrialised regions, could be seen as control data for those studies which have considered cases of childhood leukaemia around nuclear facilities, where the observation of single point clusters associated with suspected sites restricts assessments of spatial pattern in the rest of the area.(ABSTRACT TRUNCATED AT 250 WORDS)
This study presents a series of malignant parotid tumours treated at the Institut Gustave-Roussy between 1975 and 1984. The lesions represented a wide variety of histological types. Few preoperative investigations were required, management being based on histology. Effective local control requires a total parotidectomy preserving the facial nerve where possible. It should be followed by routine radiotherapy which appears to reduce the incidence of local recurrence. The rate of local recurrence also depends on the histological type. It is seen more frequently in an adenocarcinoma following a pleomorphic adenoma than in simple adenocarcinoma. Patients with inoperable disease are treated with radiotherapy alone as chemotherapy has not so far been effective. Percentage 5-year survival for the three most common tumour types is as follows: adenocarcinoma: 49; adenoid cystic carcinoma: 83, and mucoepidermoid carcinoma: 75.
The diotic summation effect is one of the three types of binaural advantage for perceiving speech-in-noise. Using a within-subject design in normally-hearing subjects having no significant noise exposure, we examined its magnitude. The average advantage was +5%, at an overall performance level of 70-80% rising to +9% when an appropriate control was used to exclude order effects introduced by the within-subject design. Diotic summation is an important component of the advantage to be derived from presentation to two ears, but the size of the binaural advantage obtained depends critically on the particular monotic baseline chosen for comparison. The methodological problems of demonstrating binaural advantages (as in binaural aiding studies) are discussed.
An international nursing research study examined the ethical decision-making of "good and experienced" registered nurses in eight countries. The subjects were asked about their decision to feed or not to feed a hypothetical terminally ill, mentally alert, elderly cancer patient who refuses to eat. Cultural variations were demonstrated in the decisions as well as differences in ethical justification. The majority of nurses who would not feed appeared to use the principle of autonomy, whereas nurses who would feed the patient used beneficence as justification. Conditions under which nurses would change their decision to either feed or not feed the patient against her will included doctor's orders and lack of peer support for the decision. The majority of nurses clearly experienced a dilemma.
Casein kinase II (CK-2) is a ubiquitous serine/threonine protein kinase, and is localized to both the cell nucleus and cytoplasm. Despite extensive biochemical similarities in their properties, there is evidence that the two forms of the enzyme exhibit certain distinctions (1). This prompted us to produce antibodies against CK-2, which could be utilized as a possible tool for investigations of the various forms of this enzyme. Specific polyclonal antibodies against the rat liver cytosolic CK-2 were raised in egg yolk of laying hens; the enzyme had repeatedly failed to elicit an immunogenic response in rabbits. The purified polyclonal antibody (egg yolk immunoglobulin, IgY) recognized all three subunits (42, 38, and 28 kDa) of the enzyme in immunoblots. The antibody when bound to a matrix was capable of removing CK-2 from solution, and the bound enzyme could be recovered from the immunoaffinity matrix with 0.1 M diethylamine. The antibody exhibited a high affinity towards CK-2 prepared from cytosol of liver, ventral prostate, and several other rat tissues, but no immunoreactivity was detected towards a number of other protein kinases tested. The subunits of the nuclear form of CK-2 (PK-N2) migrated differently when electrophoresed in parallel in the same gel. However, the antibody did cross-react with the various subunits of PK-N2 suggesting a significant homology in the immunogenic domains in the various subunits of the two forms of the enzyme.
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A retrospective review of 21,632 live births from January 1982 to July 1987 was performed to determine the incidence and risk factors associated with fractures of the clavicle in the newborn. Fifty-eight fractures (57 patients) were identified, for an incidence of 2.7 clavicle fractures per 1000 live births. Fractures of the clavicle were associated with heavy neonates and shoulder dystocia. Three patients had concurrent clavicular fractures and Erb's palsy. These findings suggest that the incidence of clavicle fractures in the newborn may be reduced by identifying the macrosomic fetus and by minimizing shoulder dystocia. When clavicle fractures occur, a brachial plexus injury should be ruled out.
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Nabumetone differs from most other nonsteroidal anti-inflammatory drugs. It is presented to the gut as a nonacidic prodrug, and is metabolized to its active form after absorption. Studies in animals and humans suggest it is less irritating to the gastrointestinal mucosa. This study compared the gastrointestinal microbleeding induced by nabumetone to aspirin (acetylsalicylic acid, ASA), and placebo in a double blind parallel study using chromium 51Cr labelled red cells to quantitate fecal blood loss (FBL) in healthy volunteers. Thirty subjects were randomized to treatment with nabumetone (2000 mg), ASA (3.6 g) or placebo for 21 days following a 7 day placebo period. Six subjects served as untreated controls. FBL in nabumetone treated subjects was not significantly different to placebo or untreated subjects. In contrast, ASA-treated subjects exhibited significantly increased FBL than the other 3 groups (P less than .0001).
Sixteen consecutive patients entered in a prospective study of non-neurogenic soft tissue tumours had lesions in the axilla. Delayed diagnosis and inappropriate biopsy prior to referral to a surgical oncologist were frequent findings. Sarcoma and fibromatosis were diagnosed in 14 cases, and the approaches used for these two diseases were fundamentally different. The functional outcome with limb salvage surgery in these patients is presented.
The major histocompatibility complex (MHC) of pigtailed macaques (Macaca nemestrina, Mn) is defined and designated as MnLA. Twenty-nine alloantisera were generated by fullsib alloimmunization and tested against a panel of 220 unrelated animals. The reactivities of different alloantisera were analyzed statistically in pairwise comparisons. Using 2 X 2 contingency tables, we calculated chi 2 independence, chi 2 allelism, and correlation coefficient values. Initially, specificities were defined by significant associations of certain sera, but some sera defined specificities individually. In all, 15 specificities were defined, and by family studies and negative correlation coefficients, a two-locus model was evident. Genetic analyses, together with statistical applications, revealed that the behavior of these specificities is consistent with the nature of MHC in other primate species, including man.
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From a sample of young male Californians, ten speakers were selected whose voices were approximately normally distributed with respect to the "easy-to-remember" versus "hard-to-remember" judgments of a group of raters. A separate group of listeners each heard one of the voices, and, after delays of 1, 2, or 4 weeks, tried to identify the voice they had heard, using an open-set, independent-judgment task. Distributions of the results did not differ from the distributions expected under the hypothesis of independent judgments. For both "heard previously" and "not heard previously" responses, there was a trend toward increasing accuracy as a function of increasing listener certainty. Overall, heard previously responses were less accurate than not heard previously responses. For heard previously responses, there was a trend toward decreasing accuracy as a function of delay between hearing a voice and trying to identify it. Information-theoretic analysis showed loss of information as a function of delay and provided means to quantify the effects of patterns of voice confusability. Signal-detection analysis revealed the similarity of results from diverse experimental paradigms. A "prototype" model is advanced to explain the fact that certain voices are preferentially selected as having been heard previously. The model also unites several previously unconnected findings in the literature on voice recognition and makes testable predictions.
An assay to determine the binding of pig spermatozoa to the zona pellucida (ZP) of pig oocytes was developed using conditions compatible with in-vitro fertilization of pig eggs and with pig sperm penetration of zona-free hamster ova. These conditions were used to define which of the pig oocyte ZP components were involved in sperm binding by a competitive inhibition approach. Assay variables that were optimized included: the method of sperm preparation; sperm preincubation time; sperm-oocyte coincubation time; sperm concentration and temperature; and methods for the separation of free from oocyte-bound spermatozoa. Inclusion of solubilized ZP in the sperm preincubation medium inhibited sperm binding approximately 50%. Both the 55K and 90K components inhibited sperm binding although the 55K component was more effective. The two polypeptides derived from chemical deglycosylation of the 55K families did not inhibit sperm binding. Of several monoclonal antibodies to the ZP components tested, only one directed against the 55K alpha glycoprotein family inhibited sperm binding. Sperm binding to pig oocyte ZP is therefore dependent on the carbohydrate moiety of the glycoproteins and appears to involve more than a single ZP glycoprotein.
The Levine-Pilowsky depression questionnaire was used to compare the qualitative and quantitative characteristics of depression in 176 patients admitted to a general hospital following a suicide attempt and 65 psychiatric inpatients with a diagnosis of major affective disorder. The study showed that despite significant age and sex differences there was a striking similarity between the groups on all measures of depression. Diagnostic and therapeutic implications of these findings are discussed, and further research directions are suggested.
An audiological investigation was performed of 20 patients suffering from the well characterized autoimmune disease systemic lupus erythematosus (SLE). In addition to threshold estimations, psychoacoustical tuning curves were measured to provide an indication of frequency-resolving ability. Comparison of these data with age, sex and socioeconomically matched controls did not show that the SLE group had significantly worse hearing.