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Biomedical subjects

G Ball

Publications and source records attributed to G Ball.

At least 55 records · Page 3Linked to original sources
PubMed1988

Clinical manifestations of cows' milk allergy in childhood. I. Associations with in-vitro cellular immune responses.

In this study 51 children who presented with symptoms of cows' milk allergy (CMA) were categorized clinically by their response to cows' milk challenge. Forty-two patients had unequivocal evidence of CMA and nine were milk tolerant. Of the patients with CMA two groups were identified. The first, made up of 32 patients, had immediate-type hypersensitivity reactions to milk associated with both positive skin-prick test (SPT) and RAST. The second group of 10 late reacting patients developed symptoms of CMA over several hours or days; significant increases in irritability, frequency of bowel actions, and rhinitis following milk ingestion were noted in this group. Leucocyte inhibition factor (LIF) produced in response to alpha-lactalbumin, beta-lactoglobulin and alpha-casein was assessed in the immediate and late reacting CMA patients as well as in the milk-tolerant group. There was no difference in LIF production between the milk-tolerant group and those with immediate reactions. However, these two groups produced less LIF than the late reacting patients for alpha-lactalbumin (P = 0.02), alpha-casein (P = 0.03) and beta-lactoglobulin (P = 0.05). A clinical dairy score card was found to be a useful instrument to assess the response of non-immediate reactions to milk ingestion.

Animals↗
PubMed1988

Homology between endoglucanase Z of Erwinia chrysanthemi and endoglucanases of Bacillus subtilis and alkalophilic Bacillus.

Nucleotide sequencing of the celZ gene encoding the extracellular endoglucanase Z of Erwinia chrysanthemi indicated the presence of an open reading frame encoding 428 amino acids. The mature protein appeared to be extended by a signal peptide of 43 amino acids; this sequence is unusually long and positively charged (+5). It was shown to function as a signal peptide by fusing it to a truncated phoA gene encoding Escherichia coli alkaline phosphatase. Comparison of the encoded sequence with those of the endoglucanases of Bacillus subtilis and alkalophilic Bacillus revealed the existence of a region of extensive homology occurring in all three proteins at about the same distance from the NH2-terminal end. These regions may be involved in substrate binding and/or catalytic sites.

Alkaline Phosphatase↗
PubMed1985

Behavior therapy for panic disorder.

Eleven patients who met DSM-III criteria for panic disorder were treated with behavior therapy techniques. Seven patients had mixed phobic avoidance and none were agoraphobic; three had no phobic symptoms. Mean duration of symptoms was 3.4 years. Treatment lasted a mean of 14 weeks and consisted of 1) education about physiology and management of panic symptoms; 2) relaxation, abdominal breathing, and cognitive anxiety management skills; and 3) imaginal and in vivo exposure. Upon termination of treatment, 10 of 11 patients were panic-free and six of seven mixed phobics showed complete remission or significant improvement of phobias. Follow-up data revealed excellent stability of remission. Clinical implications for the use of behavior therapy for panic disorder and directions for future research are discussed.

Adult↗
PubMed1981

Free radical oxidation (peroxidation)products in plasma in normal and abnormal pregnancy.

Using recently developed methods for measuring free-radical oxidation products in biological material, plasma extracts were studied in 24 women in the first two trimesters of pregnancy, in 124 women in the third trimester of pregnancy, in 20 women with pre-eclamptic toxaemia (PET), and in a control group. There was a significant progressive rise of two groups of free-radical oxidation products throughout pregnancy and a significantly greater rise in PET. In women whose diastolic blood pressure rose to above 70 mmHg there was a highly significant relation between two groups of free-radical reaction products and blood pressure.

Blood Pressure↗
PubMed1980

Relaxation and subjective estimates of muscle tension: implications for a central efferent theory of muscle control.

The relationship of "awareness of muscle tension" to depth of relaxation was explored. In one experiment, accuracy of forearm flexor control was assessed using the psychophysical method of magnitude production, and depth of flexor relaxation was measured using the integrated EMG before and after EMG biofeedback training. No consistent relationship between motor-control accuracy and depth of relaxation was found. A second, similar experiment with frontalis showed increased accuracy of frontalis control with deeper relaxation. Accuracy of passive, verbal judgments of spontaneous frontalis tension fluctuation exhibited no clear relationship with depth of relaxation. It was concluded that forearm flexor and frontalis may be under the control of distinct mechanisms, and that afferent information probably contributes to the control of neither muscle. Three structural theories of the control mechanisms were considered, and one depending on the central monitoring of efferent outflow (rather than afferent inflow) seemed most compatible with the frontalis data. Both flexor and frontalis data could be accounted for by a two-phase scheme combining central outflow monitoring with the monitoring of mental contents for arousal value at very low muscle tension levels.

Adult↗
PubMed1980

The prevalence of naturally occurring antibodies to human syncytial virus in East African populations.

A seroepidemiological study of naturally occurring antibodies to the human syncytial virus has been carried out by means of an indirect immunofluorescence test on 639 East Africans, consisting of 493 normal Ugandans, 66 Kenyan patients with nasopharyngeal carcinoma (NPC), and 80 Kenyan and Tanzanian patients with various other tumours or non-cancerous conditions. It was found that 3.4% of the normal individuals had antibodies to the virus and serial serum samples were available from 14 of these, permitting the study of antibody class in seroconversion and antibody persistence. As in an earlier survey, a significantly higher incidence of antibodies was found amongst NPC patients. Blocking and indirect immunofluorescence test with simian foamy viruses (SFV) showed some cross-reactivity between SFV 6 and the human syncytial virus, but not identity. The results are discussed in relation to the very real occurrence of natural infection by human syncytial virus in certain geographical regions.

Adolescent↗
PubMed1978

The electromicrophysiology of delta waves induced by systemic atropine.

Delta waves in the EEG can be induced by the intravenous administration of atropine. In cats we have investigated with several computer averaging programs the relationship of extracellular unit discharge to the EEG on the surface and within the cortex. We have also studied the laminar profiles and the vertical current density profiles of these slow waves. Our results indicate that surface-positive delta waves are related to events associated with excitation of cortical neurons, while surface-negative delta waves are related to a decreased probability of unit firing suggesting the possibility of inhibition. Laminar analysis of atropine-induced slow waves indicated that these were probably generated by pyramidal cells in a similar way to delta waves induced by brain lesions. These results suggest that a disturbance in cholinergic input to the cortex might be responsible for delta waves in the EEG.

Animals↗
PubMed1978

Cytogenetics of malignant epithelial cells and lymphoblastoid cell lines from nasopharyngeal carcinoma.

The malignant epithelial cells of nasopharyngeal carcinoma (NPC) and cells of lines derived form the lymphoid cells which infiltrate this tumour have been investigated cytogenetically. Chromosome spreads of lymphoblastoid cells of lines established from 7 different NPC biopsy specimens were examined after banding staining. Banding was also applied to the epithelial tumour cells of 5 further biopsy specimens freed from non-malignant infiltrating cells by passage through nude mice; epithelial cell spreads were obtained by in vivo splindle arrest. Five of the lymphoblastoid lines were found to be diploid, and 2 tetraploid; the karyotypes were essentially normal. The squamous epithelial nature of the cells in the nude-mouse-grown NPC tumours was established by light and electronmicroscopy, and 3 tumours were found to be near-triploid, and 2 near-diploid. The cells of the near-triploid tumours contained grossly abnormal chromosomes but those of the near-diploid tumours showed only relatively minor changes. Although abnormalities were observed which were specific for cells from each individual tumour, no discernible change was common to cells from all the tumours.

Adult↗
PubMed1978

Cytogenetic observations on the malignant epithelial cells and infiltrating lymphocytes of nasopharyngeal carcinoma.

Because of the presence of a No 14 chromosome marker abnormality in EB virus-carrying cells from African Burkitt's lymphoma (BL) but not from other origins, and the association of EB virus with nasopharyngeal carcinoma (NPC) as well as BL, both the malignant epithelial cells and the non-malignant lymphoid cells of NPC have been investigated cytogenetically. Chromosome spreads from seven NPC-derived lymphoblastoid lines were examined after banding; five lines were diploid and two were tetraploid. No consistent no. 14 chromosome abnormalities were found. Apart from a secondary constriction near the centromere of both no. 1 chromosomes in all cells of one diploid line, no consistent significant abnormalities were seen. Five NPC tumours, freed of infiltrating lymphoid cells by passage through nude mice, were similarly examined after spindle arrest in vivo. Two tumours were near-diploid, and three were hypo-tetraploid. Near-diploid cells had only minor chromosomal changes, but the hypotetraploid spreads from all tumours showed gross changes of uncertain origin, including frequent, major translocations. No. 14 chromosome marker changes were not seen, and there was no other consistent pattern of abnormality in tumour cells.

Animals↗
PubMed1977

Brain lesions that produce delta waves in the EEG.

Localized delta activity appears in cortex overlying a circumscribed white matter lesion. Less commonly, localized delta activity may result from a localized thalamic lesion. Unilateral diffuse delta activity appears on the side of thalamic or hypothalamic lesions. Bilateral delta activity results from bilateral lesions of the midbrain tegmentum. Localized lesions of the cerebral cortex, unilateral mesencephalic tegmental lesions, and vasogenic edema of the cerebral white matter do not produce delta activity. Marked edema of a cerebral hemisphere when no surgical decompression is provided may produce unilateral delta activity by pressure on or displacement of the brain stem or diencephalon.

Animals↗
PubMed1975

Pilot experiments with EB virus in owl monkeys (Aotus trivirgatus). III. Serological and biochemical findings in an animal with reticuloproliferative disease.

Nucleic acid hybridization with EB virus complementary RNA has demonstrated unequivocally that EB virus DNA is present in the cells of a continuous lymphoblastoid line established in culture from a pathological lymph node of an owl monkey with reticuloproliferative disease after inoculation with EB virus. There were 48 to 49 EB virus genome equivalents per cell. In addition, serological studies showed that the diseased owl monkey developed specific antibodies to EB virus capsid antigens. The antibodies were first detected by indirect immunofluorescence in serum sampled 13 weeks after inoculation, and were not found in sera from other animals without the disease. None of the monkeys developed heterophile antibodies. The significance of the biochemical and serological findings is discussed in relation to the nature of the reticuloproliferative disease and the possibility of tumour-induction by EB virus.

Animals↗
PubMed1974

Cytogenetic studies on human lymphoblastoid cell lines from Burkitt's lymphomas and other sources.

The occurrence and incidence of a characteristic banding abnormality in a No. 14 chromosome has been studied in Burkitt-lymphoma-derived and certain other EB virus-associated lymphoblastoid cell lines. The abnormality was readily detected in 7 out of 7 Burkitt lines, and when present could be seen in 100% of cells with recognizable No. 14 chromosomes. In contrast, the abnormality was not observed in 775 cells from 31 infectious mononucleosis-derived lines nor in 450 cells from 18 lines obtained from cord blood lymphocytes experimentally transformed by EB virus in vitro. The significance of the abnormality as an indication of cells transformed by the virus in vivo is discussed, and the importance of this considered in relation to a possible oncogenic role for EB virus in man.

Blood↗