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Biomedical subjects

J Seggie

Publications and source records attributed to J Seggie.

At least 37 records · Page 2Linked to original sources
PubMed1985

Transplantation for diabetic nephropathy.

The results of renal transplantation for end-stage diabetic nephropathy in 17 patients--11 receiving cadaver (CD) grafts and 6 related living donor (RLD) grafts--are reported. The transplants were rejected in 5 cases, in 4 acutely, and these patients were returned to haemodialysis; 3 of them subsequently died. One patient died of heart failure, but the graft was still functioning. The remaining 11 patients enjoy good renal function. The outcome was superior to results on dialysis, particularly for RLD grafts, and was comparable to results of transplantation for non-diabetic renal failure. Visual acuity tended to stabilize or improve after transplantation, but peripheral vascular disease progressed. Blood glucose control was suboptimal and requires more attention. Lipoproteins did not differ from those in non-diabetic patients. Renal transplantation is feasible and probably the preferred method of treatment for end-stage diabetic nephropathy.

Adult↗
PubMed1985

Lithium and twenty-four hour rhythms of serum corticosterone, prolactin and growth hormone in pigmented eye rats.

Lithium, a widely used substance for the treatment of manic-depressive illness, has been reported to alter the phase relationships of a variety of biological rhythms. We have previously found that lithium affects serum melatonin differently in albino compared to pigmented eye rats. The present study was undertaken to investigate the effect of lithium on pituitary rhythms in pigmented eye rats. Six point 24 hour maps were generated throughout a 12 hour light/12 hour dark lighting regime on separate groups of individually housed adult male Long Evans rats (with pigmented eyes), maintained for six weeks on ad lib water and either normal lab chow or lab chow supplemented with 50 mM/Kg of lithium chloride. Animals were sacrificed by rapid decapitation with care to ensure that blood samples were obtained from subjects in the resting, undisturbed state. Plasma lithium levels were 0.57 +/- 0.02 mEq/1. In comparison to normal controls, lithium treatment suppressed body weight by 19%, and increased water intake by 100%. Absolute corticosterone levels were not altered by lithium, but the 24-hour pattern was significantly changed. Growth hormone levels were significantly reduced by lithium treatment without alteration of the 24-hour pattern. Prolactin levels were significantly reduced by lithium and the normal 24-hour variation was attenuated. Comparison of these effects of lithium in pigmented eye rats with similar data from albino rats suggests that the effects on growth hormone, body weight and water intake were similar; however, the effects on prolactin and corticosterone differed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Melatonin and N-acetylserotonin stress responses: effects of type of stimulation and housing conditions.

The effects of housing condition and type of stimulation on serum melatonin and N-acetylserotonin (NAS) were investigated. Male rats were housed under a 12/12-hour light-dark cycle, with ad libitum food and water, either individually or in groups of four. At the start of the light phase, separate groups were sacrificed at rest or subjected for 3 minutes to the stimulation of cold water, noise, novel environment, or ether vapour and then decapitated at 0, 5, 15, 30 or 60 minutes after the end of stimulation. Melatonin was measured by a modified radioimmunoassay and NAS by a specific radioimmunoassay. Melatonin levels responded to stimulation with an increase, while NAS levels responded with a decrease. Housing condition had no effect on hormone response. However, the pattern of response for each of the two hormones differed greatly among the stimuli. For melatonin, cold water was the most potent stimulus, followed by noise, novel environment, and ether. NAS responded most to ether, fleetingly to cold, and in a bimodal manner to noise. The data are interpreted as suggesting that separate mechanisms regulate serum melatonin and serum NAS is response to environmental stimulation and that under appropriate control conditions melatonin from the pineal is very responsive to environmental stimuli, in a manner similar to that of pituitary hormones.

Animals↗
PubMed1985

Serum melatonin response to melatonin administration in the Syrian hamster.

Chronic daily administration of melatonin (MT) can have potent effects on reproduction in the hamster. Various theories have been elaborated to explain these effects but little information has been available on circulating levels of MT following MT administration. We have examined the serum MT response in the male hamster to a single dose of 25 micrograms MT administered in the morning or in the afternoon--the same timing and dose used by others to produce reproductive effects. With both morning and afternoon administration, serum MT increased above 1,000 pg/ml and remained above the highest basal levels during most of the 24-hour cycle. These levels are clearly supraphysiologic ones. The decline in serum MT showed two distinct components following morning administration. Half-life of the initial component which probably represents rapid distribution into tissues was 17.3 min. A half-life of 25.1 h was calculated for the second component. We conclude that use of a 25-micrograms dose of melatonin to study pineal effects may be misleading.

Animals↗
PubMed1984

Lithium and melatonin in pigmented eye rats: effects of dose and time of day.

Lithium has been suggested to exert some of its theraputic effects by modifying the function of the retinal-hypothalamic pineal pathway that is essential for the chronobiology of an organism (Seggie et al., 1983). Previous work was done in Wistar rats, an Albino species which lacks the enzyme for synthesis of eye pigment. This pigment is important in the regulation of light cued rhythms. The present project investigated effects of lithium in a pigmented eye strain. Adult male Long Evans rats were maintained individually on a 12 hour light/12 hour dark schedule with free access to water and one of three diets: (1) normal laboratory chow; (2) a low lithium diet: lab chow supplemented with 50 mM/kg of lithium chloride. Body weight and water intake were measured after six weeks on the diets. In Experiment I, separate groups of rats were sacrificed by rapid decapitation every 4 hours in the light/dark cycle. In Experiment II, animals were sacrificed every 90 min. between 12:00 and 20:00 hours during the dark cycle. Blood and pineal glands were collected for lithium determination and assay of melatonin by RIA. In Experiment I, plasma lithium levels were 0.35 +/- 0.01 and 0.57 +/- 0.02 mEq/1 for the low and high diets. Serum and pineal melatonin evidenced the expected diurnal rhythms. The diets had no effect on these parameters except at 14:00 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Lithium in pigmented eye rats: effects of dose and time of day on drinking, body weight, retinal and blood distribution.

Lithium has been implicated in chronobiology (Seggie, et al., 1982, 1983). Previous work was done in Wistar rats, an Albino species, which lack the enzyme for synthesis of eye pigment. This pigment is important in regulation of light cued rhythms. The present project extends observations to Long Evans rats, a strain which has a pigmented eye. Groups of adult male rats were fed one of three diets: (1) normal laboratory chow; (2) a low lithium diet: lab chow supplemented with 30 mM/kg lithium chloride; and (3) a high lithium diet: lab chow supplemented with 50 mM/kg lithium chloride. Adult male rats were house individually with free access to diet and water under a 12 hour light/12 hour dark schedule. After six weeks on the diets, body weight, water intake, plasma, red blood cell and retinal lithium and retinal weight were measured every 4 hours throughout the 24 hour cycle following sacrifice by rapid decapitation. Plasma lithium levels on the high diet were 0.57 +/- 0.02 mEq/l and did not evidence a diurnal rhythm. Plasma lithium levels on the low diet were 0.35 +/- 0.01 mEq/l and evidenced a small, but significant diurnal rhythm with levels lowest just before darkness and normal food intake. Red blood cell lithium levels were significantly higher than plasma levels at 0.83 +/- 0.02 and 0.52 +/- 0.02 mEq/l for the high and low diets. Low diet, but not high diet red blood cells lithium levels evidenced a significant rhythm with a pattern similar to that seen in plasma lithium levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Association of hepatitis B (HBs) antigenaemia and membranous glomerulonephritis in Zimbabwean children.

8 Zimbabwean children are discussed in whom the nephrotic syndrome (NS) was a manifestation of membranous glomerulonephritis (GN) which was associated in every case with hepatitis B antigenaemia. This marks the first occasion that such an association has been reported in African children, although it has been thoroughly documented in children in Europe, the Far East and America. Microhaematuria, hypertension and mild to moderate renal insufficiency were frequent early associated findings, and every child exhibited hypocomplementaemia and a markedly diminished immunoglobulin G (IgG) level. The disease followed a benign course in the majority, and only 1 child died in renal failure.

Adolescent↗
PubMed1984

Patterns of glomerulonephritis in Zimbabwe: survey of disease characterised by nephrotic proteinuria.

Ninety-eight Zimbabweans with glomerulonephritis characterised by nephrotic proteinuria were studied. There was no evidence to implicate Schistosoma mansoni or S. haemotobium in the aetiology, although schistosomiasis was diagnosed in 54 patients in the series. Similarly, Plasmodium malariae proved unimportant as a cause of the nephrotic syndrome, only one patient showing focal segmental glomerulosclerosis which was associated with subclinical quartan malarial infection. Nevertheless, infections were shown to play a major role in the genesis of glomerulonephritis which was associated with beta-haemolytic streptococcal, hepatitis B and syphilitic infection in 45 patients in the series. The major patterns of disease in childhood proved to be membranous glomerulopathy associated with hepatitis B antigenaemia. In young adults post-streptococcal proliferative glomerulonephritis constituted the commonest disease pattern. In older adult patients a miscellany of primary and secondary glomerulonephritides was encountered but proliferative glomerulonephritis, which was both idiopathic and streptococcus-related, predominated.

Adolescent↗
PubMed1983

The treatment of end-stage renal disease at the Johannesburg Hospital: a 17-year experience. Part II. The role of transplantation.

Experience with 525 kidney transplants performed at the Johannesburg Hospital from 1966 to 1982 is reviewed. The 1-year graft survival rates for HLA-identical related living donor (RLD) transplants, haplo-identical RLD transplants, and first and subsequent transplants from cadaver donors (CDs) are 95%, 72%, 59% and 52% respectively. One-year patient survival figures for all RLD and all CD transplants are 93% and 78% respectively. There is a slower but steady attrition in both graft and patient survival over the next 10-15 years which is the same for all patients irrespective of donor source. Infection and myocardial infarction remain the major causes of mortality and morbidity. Mortality in the 1st year after transplantation has been reduced dramatically in the last 5 years of the programme. This has coincided with the introduction of a policy of routine pretransplant blood transfusion and a less aggressive approach to the treatment of severe and recurrent rejection episodes. However, the incidence of irreversible graft rejection in the 1st year has remained the same. These results, although gratifying in a broad context, leave no room for complacency. The induction of a state of specific tolerance towards the grafted organ remains the ultimate goal in clinical transplantation.

Actuarial Analysis↗
PubMed1983

Corticomedial amygdala lesions, behavior, corticosterone, and prolactin: unexpected separation of effects.

The present experiment examines hormone: behavior relationships following lesions of the amygdala. Affective behavior and levels of corticosterone and prolactin were compared in rats with lesions of the corticomedial amygdala and in nonlesioned and sham-operated controls. Animals with lesions of the corticomedial amygdala were found to be hyperreactive, but to have normal corticosterone and prolactin resting levels and responses to stimulation. The unexpected separation of behavior and hormone responses is compared with behavior and endocrine changes seen following other limbic system lesions, and the implications for the psychoneuroendocrinology of stress are discussed.

Amygdala↗
PubMed1983

Chlordiazepoxide normalizes behaviour and adrenal response abnormalities in septal rats in a dose and time dependent fashion.

Rats lesioned in the septal nuclei display a dramatic syndrome characterized by hypoactivity in a novel environment, but exaggerated behavioural and corticosterone responses to environmental stimuli. These abnormal responses are normalized 2 hours following 15 mg/kg i.p. of chlordiazepoxide (Seggie, CCNP, 1980). The present study was undertaken to map the dose and time response characteristics of this effect and see if behaviour and corticosterone respond in parallel fashion. Chlordiazepoxide in doses of 7.5-30 mg/kg affected the hyperreactivity of septal rats is a 'U' shaped function without affecting the behaviour of non-lesioned rats. Corticosterone levels in non-lesioned rats were unaffected by chlordiazepoxide, while drug treated septal rats had corticosterone levels undistinguishable from non-lesioned control rats. The drug effects were transitory, maximal at 2 hours after injection, but absent as 48 hours after injection. General abnormalities of behaviour and corticosterone responsiveness were altered in parallel fashion by the drug, but some evidence of differences in sensitivity to the effect of the drug were noticed. Locomotion, was unaffected by the drug in lesioned and non-lesioned rats. The possibility of a GABA mechanism underlying the abnormalities of responsiveness, but not activity in septal rats is discussed.

Animals↗
PubMed1983

Chronic lithium treatment and twenty-four hour rhythm of serum prolactin, growth hormone and melatonin in rats.

This study was undertaken to extend the observations that lithium chlordie has the ability to phase shift the 24-hour pattern of a large number of physiological parameters relative to the environmental lighting cycle. Adult male Wistar rats were housed individually in a temperature and sound controlled environment under a lighting schedule of 12 hours dark/12 hours light. Six point 24-hour maps were generated by taking measurements every four hours throughout 24 hours on separate groups of rats maintained for six weeks on ad lib water and one of three diets: 1) normal lab chow, 2) lab chow supplemented with 50 mM/kg of lithium chloride, 3) lab chow supplemented with 50 mM/kg of sodium chloride to control for the effects of a possible salt load. Variables measured included plasma and red blood cell lithium and sodium concentrations, serum prolactin, growth hormone and melatonin. Plasma lithium levels were 0.7 - 1.0 mEq/L. Plasma, but not red blood cell lithium levels demonstrated a 24-hour rhythm with higher levels following the normal feeding period. Serum and red blood cell sodium levels did not differ among the diets and showed no 24-hour variation. The sodium diet had no significant effects on any of the variables measured. The 24-hour pattern of prolactin was not significantly affected by the diets, while growth hormone and melatonin levels differed in animals on the lithium diet. During the light hours when growth hormone levels are normally falling and melatonin levels are barely detectable, there were no differences on these measurements among the diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1982

Effect of chronic lithium treatment on twenty four hour variation in plasma and red blood cell lithium and sodium concentrations, drinking behavior, body weight, kidney weight, and corticosterone levels.

This study tested the hypothesis that lithium alters the phase relationships of various 24-hour rhythms. Six point 24-hour patterns were measured throughout a 12 hour light/12 hour dark cycle from separate groups of individually housed adult male wistar rats maintained for six weeks on ad lib water and either 1) Normal lab chow, 2) Lab chow supplemented with 50mM/KG of lithium chloride, or 3) Lab chow supplemented with 50mM/KG of sodium chloride. Plasma lithium levels were 0.7-1.0 mEq/1. The sodium diet had no effect on any of the variables measured relative to normal controls. Plasma but not red blood cell lithium levels demonstrated a 24-hour rhythm with higher levels during darkness. Serum and red blood cell sodium levels did not differ among the diets and showed no 24-hour variation. Lithium treated rats weighed significantly less than controls and had significantly heavier kidneys per 100 grams of body weight than controls. Resting plasma corticosterone levels demonstrated the expected 24-hour pattern in all groups, however, the lithium group evidenced higher levels during the middle of the dark hours than either control group. Water consumption also demonstrated a 24-hour rhythm. Lithium animals consumed far greater quantities of water than controls and this behaviour became increasingly exaggerated over the duration of the study. The data are interpreted as suggesting that lithium broadens the peak of twenty four hour rhythms such that normal elevation in these measures appear earlier and last longer.

Animals↗
PubMed1981

Esophageal obstruction by phytobezoar. Rare complication of gastric bezoar.

We describe a patient in whom a gastric phytobezoar was regurgitated into the esophagus during an episode of vomiting, giving rise to sudden dysphagia. The bezoar remained impacted for 3 days during which time a sever ulcerative esophagitis due to pressure necrosis and secondary infection developed. Healing has been accompanied by esophageal stricture formation which still necessitates esophageal dilatation at intervals.

Adult↗