Showing papers by "Monash University published in 1979"

Representation of sound frequency and laterality by units in central nucleus of cat inferior colliculus

Abstract: 1. The discharges of 632 units were isolated extracellularly during 42 penetrations of the central nucleus of the inferior colliculus (ICC) in 21 adult cats lightly anesthetized with pentobarbital and ketamine. Microelectrode penetrations were directed from caudal to rostral through ICC, parallel to the Horsley-Clarke (H-C) horizontal and sagittal planes. 2. The threshold best frequency (BF) and binaural response properties were examined for each unit, with the aim of elucidating the organization of these discharge characteristics within ICC. 3. Binaural unit classes consisted of monaural (contralateral) (EO), binaurally phase-sensitive (delay), contralateral excitatory/ipsilateral inhibitory (EI), binaurally excitatory (EE), and other more heterogeneous interaction patterns (other). 4. Detailed histological reconstruction of electrode tracks allowed the recording site for each unit to be related to the three dimensions of ICC. This structure was divided into three lateromedial and three rostrocaudal blocks such that each block contained a similar number of units, enabling meaningful statistical comparisons. Low (3.2 kHz greater than BF) and high (3.2 kHz less than BF) best-frequency classes provided a correlate of dorsoventral location. 5. The arrangements of BFs within ICC were found to be compatible with a model of this structure in which units having similar BFs are organized into layers lying in the H-C horizontal plane medially and gradually tilting in both a ventrolateral and ventrorostral direction. Low frequencies are concentrated dorsally and laterally; high frequencies, ventrally and medially. A rostrocaudal BF difference arises only in lateral aspects of the ICC, where lower frequencies are encountered rostrally. 6. Binaural response classes were distributed differentially throughout ICC. Thus, EO units were concentrated caudally, ventrally, and laterally, while delay units were in greatest numbers rostrally, dorsally, and laterally--almost totally segregated from EO and EI units. The latter populations overlapped ventrally and laterally, but EI units were in greatest density rostrally. The EE class occurred throughout the nucleus, but was most common medially. 7. It is suggested that the differential distributions of binaural responses reflect a partial segregation of the afferents, arising in the superior olive and cochlear nucleus, which terminate in ICC. The central nucleus of the inferior colliculus thus may be composed of several functionally segregated subregions contained within a common tonotopic organization.

A comparative study of resource utilization in natural populations of Drosophila melanogaster and D. simulans.

Abstract: Data were collected over four vintage seasons at the "Chateau Tahbilk" winery. The distribution of adults, larvae and pupae of D. melanogaster and D. simulans was recorded over a pile of grape residues during two different stages of its decomposition. Active fermentation characterized the first of these stages, but was much less apparent in the later stage. The distribution of adults was similar for both stages. However, while larvae and pupae of both species were observed in the post fermentation residues essentially only D. melanogaster larvae and pupae were present during the fermentation stage. During this stage larvae were aggregated beneath the surface to a depth of 10 cm. Here the average temperature was about 29°C and ethanol and acetic acid concentrations were around 7% (v/v) and 3% (v/v), respectively.Laboratory results allow a description of the physiological and behavioural responses of both species to ethanol or acetic acid concentration and to temperature differences. These results appear sufficient to explain the distribution of the species between and within the residue stages. However, before general statements of resource utilization or species interaction can be made, the need to study different stages of the life cycle is highlighted.

Geographic tongue—a manifestation of atopy

Abstract: One hundred patients with geographic tongue have been studied for evidence of an association with atopy. There was a significantly high frequency of personal and/or family history of asthma, eczema and hay fever amongst the patients when compared to a control population. A raised total serum IgE( greater than or equal to 200 u/ml) was significantly more frequent in patients compared to a control population. These findings confirm the impression that in some patients geographic tongue is a sign of atopy.

Endocrinology of male infertility.

Abstract: Endocrinological aspects of male infertility are reviewed beginning with the physiological interrelationship between the testis and the hypothalamo-hypophysical unit. The failure of the pituitary to secrete follicle stimulating hormone (FSH) and luteinizing hormone (LH) results in disruption of testicular function and infertility. However in men presenting with infertility gonadotropin deficiency accounts for less than .5% of the causative factors. If deficiencies in FSH or LH are proved a hypothalmic or pituitary lesion should be sought. Nevertheless mreasurements of FSH LH and prolactin are useful tests in the management of male infertility. Of greatest importance is measurement of serum FSH which provides a useful index of the state of the seminiferous epithelium when the concentration is related to sperm density: high concentration associated with severe oligospermia or azoospermia usually denotes untreatable infertility. Elevated LH and low testosterone levels have been found in about 30% of men with severe degrees of testicular damage and are indicative of interstitial cell failure. Prolactin measurements are mainly associated with impotency rather than infertility. Hormonal treatment of male infertility is often indicated. For example replacement therapy for gonadotropin deficiency is successful. Androgen injections of testosterone esters will suppress spermatogenesis so when treatment is stopped sperm counts will rebound to concentrations greater than pretreatment levels. That endocrine factors can potentiate testicular damage is postulated based on the measurement of FSH as an indicator of seminifirous tubule disruption resulting in disruption of spermatogenesis.

Killing Humans and killing Animals

Abstract: It is one thing to say that the suffering of non‐human animals ought to be considered equally with the like suffering of humans; quite another to decide how the wrongness of killing non‐human animals compares with the wrongness of killing human beings. It is argued that while species makes no difference to the wrongness of killing, the possession of certain capacities, in particular the capacity to see oneself as a distinct entity with a future, does. It is claimed, however, that this is not the only factor to be taken into account: pleasant or happy life is in itself good. The application of these conclusions to killing animals for food is then considered, with some passing reflections on infanticide.

Dividends and the Value of the Firm: Evidence from the Australian Equity Market:

Abstract: A version of the Black and Scholes dividend yield experiment is conducted, with a view to determining whether there exists a preference for dividends versus capital gains. Using data from the 1960s the experiment reveals a relatively large relationship between dividend yields and risk-adjusted share returns, in the year subsequent to the payment of the dividend yields. The observed dividend effect is too large to be explained by major hypotheses concerning market-wide preferences for or against dividends.

Menstrual characteristics of 2,343 women attending the Shepherd Foundation.

Abstract: Summary: Menstrual characteristics of 2,343 women attending the Shepherd Foundation Health Testing Centre have been analyzed utilizing a computer system of data analysis. The incidence of menstrual pain was, 43% and premenstrual tension 75%. The best estimate of normal cycle length was 21–35 days, 1.5% of women having cycles less than 21 days. The duration of menstrual loss was 1–7 days, 3% of women bleeding for more than 7 days. Utilizing the various responses to questions concerning menstrual and cycle length, menstrual pain and premenstrual tension, 150 patterns were found, the 10 most common patterns accounting for 40% of the population; most of the latter patterns included menstrual pain and premenstrual tension. Authorities disagree upon the definitions of normal menstruation and there are serious implications from the lack of knowledge in this area, both for the individual patient and the cost of health care. The formation of a health committee to determine national standards for defining normal menstruation is advocated.

The sympathetic innervation of the mammalian ovary. A review of pharmacological and histological studies.

Abstract: The aim of this article is to review the literature concerning the nature and function of the sympathetic innervation of the mammalian ovary. We focus our attention upon evidence relating to suggestions that ovarian smooth muscle participates in ovulatory events, and that such participation may be modulated by the local neural supply. Guttmacher & Guttmacher (1921) mentioned that this possibility was first suggested nearly 70 years before they observed smooth muscle-like cells in the follicular walls of sow ovaries and found that isolated follicular walls were contracted by physostigmine and relaxed by adrenaline. However, Claessen (1947), using polarisation microscopy, was unable to confirm the presence of smooth muscle in the apices of follicles from a number of species, and interest in the Guttmachers' findings temporarily lapsed. In 1967, Jacobowitz & Wallach reported the findings of a histological study of ovaries from cats, monkeys and humans in which they observed catecholamine fluorescence associated with smooth muscle-like cells in the stroma. In 1969, Rocereto, Jacobowitz & Wallach demonstrated that the cat isolated ovary exhibited spontaneous mechanical activity and was reactive to catecholamines. These investigations together with those of Owman & Sjoberg (1966) and Sjoberg (1967) initiated a resurgence of interest in the possibility that the adrenergic innervation of the ovary may play a functional role in ovarian processes; in particular that it might affect the contractility of smooth muscle and so participate in ovulation. With the development of techniques such as electron microscopy and fluorescence histochemistry, together with greater sophistication of pharmacodynamic analysis, an increasing number of publications concerned with the role of smooth muscle and adrenergic innervation in the ovary has appeared in the recent literature. Reference to some of this work is found in the reviews of Marshall (1972, 1973) and Bell (1972). A comprehensive review devoted specifically to the roles of catecholamines and nerves in ovulation was published by Bahr, Kao & Nalbandov in 1974. Their review described the sympathetic innervation of avian as well as of mammalian ovaries and the possible function of such innervation. They considered evidence relating to several possible roles, including modification of contraction of ovarian smooth muscle, participation in ovulation, and/or control of the ovarian vasculature, and concluded that nerves play some role in ovulation, but that it is not clear how this effect is mediated.

The effect of dehydration and rehydration on the nitrogen content of various fractions from resurrection plants

Abstract: Nitrogen contents were determined in 20 species of “resurrection plants”,i.e. plants with leaves which are able to revive from an air-dry state (viz. Boea hygroscopica, Borya nitida, Cheilanthes sieberi, Coleochloa pallidior, C. setifera, Craterostigma plantagineum, Myrothamnus flabellifolia, Oropetium capense, Pellaea calomelanos, P. falcata, P, viridis, Polypodium polypodioides, Ramondia pyrenaica, Selaginella lepidophylla, Sporobolus stapfianus, Talbotia elegans,Tripogon loliiformis, Xerophyta retinervis, X. villosa, X. viscosa), and in three desiccation sensitive species (Eragrostis tenuifolia, Selaginella kraussiana andSporobolus pyramidalis). In a preponderance of resurrection plants insoluble nitrogen content fell during dehydration of intact plants and soluble non-protein N rose. Both changes were particularly marked in species which lose chlorophyll and thylakoid structure during drying. These trends were usually only partially reversed after 24 h rehydration. Recovery of14C-leucine incorporation in rehydrating leaves was slow. Leaves of desiccation sensitive vascular plants tended on the average to lose soluble protein rather than insoluble N during drying, and tended to have higher soluble non-protein N contents than tolerant plants. However, similarity in the changes in N-contents inXerophyta villosa leaves killed by airdrying compared to leaves surviving air-drying, opposes the view that death was due to excessive loss of protein.

Long-term cimetidine in duodenal ulcer disease.

Abstract: Forty patients with chronic duodenal ulcer who had healed endoscopically with a 6-week course of cimetidine were randomized double blind to 1 year of either placebo or cimetidine tablets 400 mg bid (20 patients in each group). Patients were seen at monthly intervals, and endoscopy was performed at clinical relapse or on completion of 1 year. One of 20 patients on active cimetidine relapsed clinically and endoscopically at 3 months; 16 of 20 patients on placebo relapsed clinically and endoscopically within 9 months, the majority within 3 months, and 2 were shown to have asymptomatic chronic ulcers at routine 12-month endoscopy. None of the 19 patients on active cimetidine routinely endoscoped at 12 months showed evidence of ulceration. This study confirms a high relapse rate when short-term cimetidine is ceased and indicates that maintenance treatment with cimetidine prevents relapse.

Lymphopenia and lymphocyte transformation in alcoholics.

Abstract: The basis of peripheral blood lymphopenia observed in patients with chronic alcoholism and liver disease was investigated by examining the effect of sera of these patients on in vitro transformation of normal human peripheral blood lymphocytes. A positive correlation was demonstrated between the serum inhibition of phytohaemagglutinin- and pokeweed mitogen-induced transformation and the degree of lymphopenia. Thus serum factors may contribute to the observed lymphopenia by inhibiting lymphocyte production in vivo.

Plasma vasopressin and human neurophysins in physiological and pathological states associated with changes in vasopressin secretion.

Abstract: Using sensitive specific RIAs for vasopressin (AVP) and the two major human neurophysins, the relationship between AVP and the individual human neurophysins was investigated in man by measuring changes in plasma concentrations in physiological and pathological states known to be associated with changes in AVP secretion. Dehydration, water loading, and hemorrhage produced small but significant changes in plasma AVP concentrations without changes in the individual human neurophysins. In response to the stimulus of cigarette smoke inhalation, large parallel changes in plasma AVP and human neurophysin I (HNPI) levels were seen without change in plasma human neurophysin II (HNPII) levels. In the pathological states of diabetes insipidus and the syndrome of inappropriate antidiuretic hormone secretion, the observations more strongly supported a specific association between AVP and NHPI. In eight patients with central diabetes insipidus, plasma AVP and HNPI levels were low or undetectable, while plasma HNPII lev...

Social bandits, modern capitalism and the traditional peasantry. a critique of Hobsbawm.

Abstract: Eric Hobsbawm's outline of the concept of social banditry suggest certain conditions of existence for that mode of primitive rebellion. Primary among these conditions are the presence of a ‘traditional peasant environment and the absence of ‘industrial capitalism’. This paper presents a critique of Hobsbawm's specifications, and suggest two alternative conditions: the presence of class conflict which unites direct producers, and the absence of effective, institutionalised political organisation of producers’ interests. This reformulation is illustrated by reference to the Kelly Outbreak in late nineteenth century Australia.

Sequential changes in circulating levels of angiotensin i and ii, renin, and bradykinin after captopril

Abstract: Venous blood levels of angiotensin I, angiotensin II, bradykinin and renin were measured before, and 30, 60, 90 and 120 minutes after, the administration of Captopril (50 mg) to eight normal subjects. Similar measurements were made in a patient with proved renovascular hypertension. In all subjects, there were significant increases in the levels of renin and angiotensin I, with reciprocal changes in angiotensin II, but no increase in the level of bradykinin. These changes were maximal at 90 minutes. In the patient, blood pressure fell in parallel with the angiotensin II levels. In the normotensive subjects, there was a significant diuresis and natriuresis after the administration of Captopril. Raised levels of circulating bradykinin, with potentiation after Captopril, were measured in an anaesthetized dog given exogenous bradykinin by infusion. These studies indicate that the hypotensive effect of Captopril is not due to raised circulating levels of bradykinin, and suggest a contribution by an intrarenal effect of the drug.

The Humean Origin of the Contemporary Monetary Approach to the Balance of Payments

Abstract: I. Introduction, 655.—II. The essence of the modern monetary approach, 657.—III. The price-specie-flow mechanism of David Hume, 663.—IV. Concluding observations, 668.

Prostatitis and Male Infertility: A Pilot Study. Possible Increase in Sperm Motility with Antibacterial Chemotherapy

Abstract: The cytology and bacteriology of urethral urine specimens and expressed prostatic secretions were examined in 24 infertile men suspected of having chronic prostatitis. Lencocytes were found and commensal bacteria cultured from most subjects but these were unrelated to clinical features, seminal characteristics or the outcome of treatment. Infection with pathogenic bacteria was not found in any subject. Despite this, there was a significant increase in sperm motility after antibacterial treatment, principally with erythromycin or cotrimoxazole, and three pregnancies coincided with the improvement. It is concluded that antibacterial therapy may improve fertility in patients with low sperm motility, but more investigation is necessary before the role of genital tract infection in male infertility can be placed in its proper perspective.

Muscle protein degradation in premature human infants.

Abstract: 1. Myofibrillar protein degradation has been measured by the rate of 3-methylhistidine excretion in premature infants weighing between 635 g and 1295 g. Analyses were made in conjunction with 1–3 day nitrogen balance studies. 2. In 56 balance studies in 36 infants, total muscle protein breakdown varied between 0·70 and 2·58 (mean 1·05) g day−1 kg−1 body weight while the percentage of total muscle protein degraded each day was between 3·3 and 8·3 (mean 4·8). 3. Both total and fractional rates of protein breakdown showed highly significant negative correlations with nitrogen retention but no relationship to total energy input. 4. Protein degradation was higher than average in infants who were losing weight at the time of the balance study, lower in infants who were gaining weight and higher in those who died within 2 weeks of the analysis. 5. Myofibrillar protein breakdown was not different between infants fed orally and those receiving total parenteral nutrition. 6. Generally the effects of nitrogen and energy status on muscle protein degradation in the premature infants are different from changes reported in adult human beings or adult rats. We suggest that this difference may be a consequence of the very limited energy reserves of the premature infant.

Suppressive effect of alcoholic liver disease sera on lymphocyte transformation

Abstract: The effect of alcoholic patient sera on in vitro lymphocyte transformation was studied using mitogen-induced uptake of 3H-thymidine to measure blastogenesis. With pokeweed mitogen as the stimulus, transformation of normal lymphocytes in sera of alcoholics with either normal or fatty livers was not significantly different from that obtained in pooled human serum (PHS). However, in sera of patients with either alcoholic hepatitis or inactive cirrhosis mean transformation was significantly reduced (P <0·001, <0·02 respectively). With phytohaemagglutinin-P or concanavalin A as mitogens, suppression of transformation was not as marked but followed the same pattern. A significant negative correlation was observed between the magnitude of transformation and serum bilirubin and aspartate aminotransferase levels. An intra-patient comparison of the effects on transformation of normal lymphocytes by simultaneously collected peripheral and portal venous sera, and of peripheral sera obtained before and after portasystemic shunt surgery, indicated that the factor(s) responsible did not originate in the splanchnic circulation nor did it accumulate in the serum because of failed hepatic clearance. By performing transformation experiments in the presence of inhibitory patient sera diluted with PHS it was possible to show that these sera caused true inhibition of transformation rather than suppression due to failure to sustain cell culture because of nutritional deficiencies. Inhibitory sera did not contain high levels of the enzyme thymidine phosphorylase and did not significantly inhibit binding of 125I-labelled mitogens to the lymphocyte surface. These findings indicate that the inhibitory effect of sera from alcoholics is of potential in vivo importance, that the effect increases with the degree of heptocyte damage, and that it is unrelated to the nonhepatic metabolic affects of chronic alcoholism.

Cephaloridine prophylaxis in resection of the large intestine.

Abstract: A controlled prospective clinical trial of cephaloridine chemoprophylaxis in resection of the large intestine was undertaken between 1974 and 1978. Data were available on 159 of 177 unselected patients. All were operated on by one surgeon. Three groups were studied: intraabdominal resection and anastomosis (102 patients); pullthrough resection and anastomosis (30 patients): and resection, with colostomy or ileostomy, without anastomosis (27 patients). In the total patient series cephaloridine reduced wound infection from 38.3% to 15.4% (P< 0.003). There was no significant decrease in intraabdominal infection. In the group of patients undergoing intraabdominal resection and anastomosis the wound infection rate was reduced from 40.0% to 14.9% (P< 0.01). Cephaloridine reduced wound infection from 50.0% to 21.4% (P = 0.05) in those patients in whom drainage tubes were inserted. A decrease in the incidence of faecal fistula from 10.9% to 4.3% was not significant. Wound infections were not reduced significantly after pullthrough excisions or resections without anastomosis. The results support the routine prophylactic use of cephalosporins in patients undergoing intraabdominal resection of the large intestine with anastomosis.