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M Holliday

Publications and source records attributed to M Holliday.

30 records · Page 2Linked to original sources
PubMed1986

Excitatory conditioning of individual Drosophila melanogaster.

Testing individual animals from a heterogenic population of Drosophila melanogaster, we demonstrate conditioning of the proboscis extension reflex. The presentation of paired (conditioning) stimuli produced (a) an increase in the average number of conditioned responses over trials, (b) measured differences in performance levels among individual subjects, and (c) a sex difference, with more males conditioned than females, and those that did did so more quickly. The presentation of unpaired (control) stimuli produced significantly lower average levels of acquisition responding and a change in the distribution of individual response patterns. Neither central excitatory state nor sensitization induced by the conditioned or unconditioned stimuli directly affected the conditioned response, whereas unconditioned stimulus preexposure adversely affected performance levels. Presenting the unpaired (extinction) stimuli after conditioning produced less of a decline in responding than did an extinction procedure with removal of the unconditioned stimulus. With the ability to identify individual differences in acquisition and extinction patterns, and given the relatively large number of individuals that can be tested simultaneously on the automated stimulation apparatus, it is now possible to make precise behavioral measurements on samples large enough for the behavior-genetic analysis of D. melanogaster with conditioning as the phenotype.

Animals↗
PubMed1983

Counterimmunoelectrophoresis in the serodiagnosis of Legionnaires' disease.

Counterimmunoelectrophoresis (CIE) was found to be a rapid, specific method for detecting circulating antibodies to Legionella pneumophila, using a simple ultrasonically disrupted antigen. The diagnostic specificity of the technique was 93% and the diagnostic sensitivity was 86.3%. Both IgM and IgG classes of antibody can be detected. There is some cross-reactivity between serogroup 1 and serogroup 6 but none between serogroup 1 and serogroups 3, 4, and 5. It is suggested that CIE may provide a simple, reproducible screening test for Legionnaires' disease.

Counterimmunoelectrophoresis↗
PubMed1980

Discrimination learning of an instrumental response in individual Drosophila melanogaster.

By using a unique methodology and a versatile series of choice points in two distinct apparatuses, individual Drosophila were shown to possess the ability to learn. This behavior can be controlled by a discriminative stimulus (substrate texture). Following a correct response in the presence of the discriminative stimulus at a horizontal choice point, fruit flies bred for negative geotaxis were given the opportunity to ascend a vertical alley leading to another choice point. When cues were consistent, reliable learning occurred. When cues were inconsistent, learning did not occur. Cue reversal produced the classic temporary increase in "incorrect" responses. The success of this paradigm is due, in large part, to the reduction of noxious and competing stimuli.

Animals↗
PubMed1977

Oxygen consumption in the azotemic rat.

To test the hypothesis that basal energy expenditure may be abnormal in azotemia, oxygen consumption was studied in partially nephrectomized, azotemic male Sprague-Dawley rats and sham operated control rats 10, 16, and 31 days after surgery. Observed decreased oxygen consumption in the azotemic group was related to their decreased body weight. There was no significant difference in oxygen consumption between groups when oxygen consumption values were related to weight.75.

Animals↗
PubMed1975

Measurement of glomerular filtration rate by fluorescent excitation of non-radioactive meglumine iothalamate.

The clearance of non-radioactive meglumine Iothalamate (Conray 60), assayed by fluorescent excitation analysis, has been shown to be a good indicator of the glomerular filtration rate (GFR). Investigations in rats by the constant infusion technique showed a good correlation with insulin clearance. In a group of ten children and one adult, we obtained excellent agreement between GFR determinations by clearance of Conray 60 and I-125 sodium Iothalamate, using the single injection technique, and taking samples from 10 min to 4 hr after injection. The decay curve was resolved into two exponential components. We have also shown that the 3 and 4 hr samples, fitted to a single exponential function, yield good agreement with GFR determinations using a double exponential model. The GFR determination method presented here is accurate, simple, cost effective, and involves no radiation exposure to the patient.

Adult↗
PubMedDate not supplied

Is there an independent association between parity and maternal weight gain?

The independent associations between parity and maternal body mass index (BMI), and between parity and maternal weight gain, were investigated using a combination of cross-sectional and longitudinal analyses based on a retrospective, repeat-pregnancy study that examined the change in maternal body weight from the beginning of one pregnancy to the beginning of the next. A group of 523 multiparous women who had been weighed regularly during pregnancy, and none of whom had fallen pregnant less than 12 months after the birth of their previous child, were examined. Sociodemographic, behavioural, medical, obstetric and perinatal data, together with antenatal measurements of maternal body weight and height, were abstracted from each mother's obstetric notes. Parity was found to be independently associated with maternal BMI (p < 0.001), gestational weight gain (p < 0.001) and interpregnancy weight gain (p = 0.032). Women of different parities were found to be at differential risk of long-term weight gain for two reasons. First, primiparous women are at risk of long-term weight gain because they gain the most weight during pregnancy, and high gestational weight gain is in itself a risk factor for long-term weight gain. Second, women of higher parity (4+) are at risk of long-term weight gain because they gain more weight in association with pregnancy, irrespective of the amount of weight they gain during their pregnancies. For women of parity 3 or less, the association between maternal body weight and parity appears to be the result of cumulative weight gained during successive pregnancies. For women of greater parity, the association between maternal body weight and parity is partly the result of cumulative excess gestational weight gained during successive pregnancies, and partly the result of gaining more weight from the beginning of one pregnancy to the next at later pregnancies.

Adult↗
PubMedDate not supplied

Electroneurographic evaluation of the facial nerve. Method and technical problems.

Electroneurography (ENoG) is emerging as a useful clinical tool in evaluation of acute facial nerve paralysis. The method of test performance can have an influence on the test results. This paper describes in detail the method used to perform ENoG at the University of Zurich. The variables that affect the results and methods of avoiding technical problems are emphasized. If ENoG is to be used clinically, the examination should be performed in a manner similar to that described in reports from this institution.

Action Potentials↗
PubMedDate not supplied

Adenoid cystic carcinoma of the nasopharynx. Case reports and literature review.

Adenoid cystic carcinoma of the nasopharynx is a rare disease with 34 previously reported cases in the literature. We report three additional cases with clinical presentation, treatment, and outcome. The presenting symptoms were facial pain in one case, middle ear effusion and epistaxis in another, and diplopia in the third. Radiotherapy was administered with relief of symptoms in all three cases. However, two patients with long-term follow-up developed local recurrence as well as distant metastases. The literature review showed that patients with this disease present with symptoms and signs such as insidious onset of facial pain, epistaxis, diplopia, and hearing loss. The final outcome, despite vigorous treatment, was dismal.

Adult↗