Thabo Mbeki and the AIDS 'jury'

This paper examines the debate regarding efforts by the South African government to control the spread of HIV infections, with particular reference to events surrounding the 13th International AIDS conference. We posit that the reaction of the medical, pharmaceutical, and media sectors to the stance by the President Mbeki on HIV control amounts to an over-simplification of a very complex issue. Empathy and sincere partnership are required to address South Africa's worsening AIDS situation.

Study of plasma factors associated with neutrophil activation and lipid peroxidation in preeclampsia

Neutrophil activation occurs in women with preeclampsia and is resolved after delivery. The present study examined whether circulating factors in plasma of women with preeclampsia caused neutrophil activation and lipid peroxidation. Twenty-one women with proteinuric preeclampsia were matched for age and gestational age with 19 normal pregnant women. Plasma was collected from all subjects before delivery and at 6 weeks postpartum and incubated with autologous white-cell buffy coat collected at the postpartum visit. Neutrophil activation was assessed by level of CD11b and CD18 expression after incubation with autologous antepartum or postpartum plasma. Lipid peroxidation was assessed by measurement of F(2)-isoprostanes in plasma, plasma-white cell incubates, and urine. Neutrophil CD11b and CD18 expression was not differentially altered by incubation with plasma from either women with preeclampsia or normal pregnant women and was similar between groups when incubation was performed with plasma collected after delivery. In preeclampsia, plasma F(2)-isoprostanes were significantly increased before and after delivery compared with controls. Plasma F(2)-isoprostanes were increased 2-fold after incubation of plasma with buffy coat, but preeclamptic women had higher levels compared with those of controls when either pregnant or postpartum plasma was used. In pregnant preeclamptics, plasma F(2)-isoprostanes were positively correlated with lymphocyte count. Six weeks after delivery, plasma F(2)-isoprostanes in the preeclamptic women were significantly positively associated with lymphocyte count and cholesterol and negatively associated with albumin. In conclusion, the present study does not suggest that a stable circulating factor causes neutrophil activation in preeclampsia. However, lipid peroxidation is elevated before and after delivery in women with preeclampsia, which suggests that these women may have an underlying predisposition to increased oxidative stress that may be driven by or contribute to a persistent low-grade inflammatory response.

Role of ovarian hormones in the pathogenesis of impaired detrusor contractility: evidence in ovariectomized rodents

PURPOSE

Although detrusor hyperactivity with impaired contractility is a common urodynamic finding in elderly subjects, to our knowledge its pathogenesis remains unknown. Biopsy studies indicate that subjects with detrusor hyperactivity and impaired contractility have ultrastructural evidence of dysjunction and degeneration patterns in isolated detrusor hyperactivity and impaired contractility, respectively. Based on the known cellular effects of estrogen we postulated that declines in ovarian hormone production may contribute to the pathogenesis of detrusor hyperactivity with impaired contractility.

MATERIALS AND METHODS

Mature 13 to 14-month-old female Fisher 344 rats were studied 4 months after bilateral ovariectomy or sham surgery. Detrusor structure was evaluated by electron microscopy and contractility was evaluated by muscle strip studies.

RESULTS

After bilateral ovariectomy detrusor smooth muscle decreased by 25% with a 12% decrease in the number of nucleated muscle profiles and degenerative changes in many axons. Muscle strips from bilaterally ovariectomized animals generated 40% to 50% less tension per strip in response to carbachol than strips of equal size from sham operated animals with no apparent change in muscarinic receptor affinity.

CONCLUSIONS

Bilateral ovariectomy resulted in many changes of the degeneration ultrastructural pattern but in none of the characteristic features of the dysjunction pattern. Our results indicate that the mature rodent detrusor and its innervation are sensitive to prolonged ovarian hormonal deficiency, contributing to impaired contractility in rodents. Future studies are required to establish whether estrogen has a role in the degeneration ultrastructural pattern or impaired contractility in humans.

Users in the driving seat or sitting alongside map-reading?

The government agenda is clear. At the highest level users are involved in policy making. We as service providers need to show evidence that users views are elicited and used to improve the quality of care. The tool bag of techniques used to elicit users views will be explored--questionnaires, structured interviews, focus groups and innovative cognitive techniques such as perception score cards. We explore the continuum of user-led qualitative techniques to provider-led quantitative approaches. Building a framework of techniques which cover the diverse needs of people using a speech and language therapy (SLT) service is a challenge. A greater challenge is using the views of users to bring about meaningful change.

In vivo and in vitro induction of human cytochrome P4503A4 by dexamethasone

PURPOSE

The aims of these experiments were to determine the effect of a therapeutic regimen of dexamethasone on cytochrome P4503A4 (CYP3A4) activity in healthy volunteers; and the concentration-effect relationship between dexamethasone and CYP3A4 activity in primary human hepatocyte cultures.

METHODS

The effect of dexamethasone (8 mg administered by mouth two times a day for 5 days) on CYP3A4 activity in 12 healthy volunteers was assessed with the erythromycin breath test and urinary ratio of dextromethorphan to 3-methoxymorphinan. Concentration-effect of dexamethasone on CYP3A4-dependent testosterone 6-beta-hydroxylation was determined in human hepatocytes treated with 2 to 250 micromol/L dexamethasone.

RESULTS

The percent of erythromycin metabolized per hour increased from 2.20% +/- 0.60% (mean +/- SD) at baseline to 2.67% +/- 0.55% on day 5 of dexamethasone (mean increase in hepatic CYP3A4 activity 25.7% +/- 24.6%; P = .004). The mean urinary ratio of dextromethorphan to 3-methoxymorphinan was 28 (4.8 to 109) and 7 (1 to 23) at baseline and on day 5 of dexamethasone (mean decrease = 49%; P = .06). Substantial intersubject variability was observed in the extent of CYP3A4 induction. The extent of CYP3A4 induction was inversely correlated with baseline erythromycin breath test (r2 = 0.58). In hepatocytes, dexamethasone 2 to 250 micromol/L resulted in an average 1.7-fold to 6.9-fold increase in CYP3A4 activity, respectively. The extent of CYP3A4 induction with dexamethasone in hepatocyte preparations was inversely correlated with baseline activity (r2 = 0.59).

CONCLUSIONS

These data demonstrate that dexamethasone at doses used clinically increased CYP3A4 activity with extensive intersubject variability and that the extent of CYP3A4 induction was, in part, predicted by the baseline activity of CYP3A4 in both healthy volunteers and human hepatocyte cultures.

Telephone support for Canadian nurses in HIV/AIDS care

An assessment study was conducted with Canadian nurses (N = 177) in HIV/AIDS care to determine how social support influences the relationship between job stress and health (job satisfaction and burnout). The assessment study revealed that social support and coping both moderate the effects of these stressors on nurses' health and functioning outcomes (i.e., job satisfaction and burnout). Accordingly, the follow-up study tested the effectiveness of an intervention designed to enhance social support, promote the use of certain coping strategies for managing occupational stress, and prevent burnout in nurses. Telephone support groups, co-led by an expert facilitator and an expert AIDS nurse, were tested in a demonstration project for nurses in HIV/AIDS care (n = 30). The nurse participants reported that the intervention enhanced their coping, confidence, relationships, client care, and connections to the HIV/AIDS nursing community.

Upregulation of an opioid-mediated antinociceptive mechanism in transgenic mice over-expressing substance P in the spinal cord

In transgenic mice expressing ectopic substance P fibres in the spinal white matter, a normally innocuous mechanical stimulus induces hyperalgesia and allodynia which are reversed by substance P and N-methyl-D-aspartate receptor antagonists. This period of enhanced excitation is followed by a rebound overshoot in these animals. As previous evidence indicates opioid mechanisms in a similar rebound in normal animals, the present study was done to determine the effects of systemic administration of morphine and the opiate receptor antagonist, naloxone, on the stimulus-induced responses in the tail withdrawal reflex. Once baseline reaction times had been taken, different combinations of saline, naloxone and morphine were administered intraperitoneally to transgenic and control mice of either sex. A mechanical conditioning stimulus of 450g was then applied to the tip of the tail for 2s. This stimulus was innocuous in control mice given saline or naloxone, but provoked a nociceptive response in transgenic mice given these compounds. In control and transgenic mice, following morphine administration there was an antinociceptive effect. In control mice the subsequent mechanical stimulus had no effect. However, in transgenic mice the mechanical stimulus produced a further antinociception. Naloxone blocked the effect of morphine and the subsequent conditioning stimulus in both control and transgenic mice. The results indicate that while morphine is equally effective on the withdrawal reflex in both types of animal, in the transgenic mice morphine reveals an intrinsic, naloxone-sensitive antinociceptive mechanism. The data are interpreted to suggest that over-expression of substance P or some other factor in the spinal cord of transgenic mice is associated with the up-regulation or facilitation of an opiate-mediated intrinsic antinociceptive mechanism. This is a novel observation because the genetic manipulation in this transgenic mouse results in a transient over-expression of nerve growth factor during development that leads to the formation of ectopic primary afferent fibres in the spinal cord containing substance P. These fibres persist indefinitely after the nerve growth factor levels return to normal. Opioid mechanisms, which are likely of dorsal horn origin, do not fall under the direct influence of nerve growth factor mechanisms and therefore the intriguing possibility is raised that opioid mechanisms in the spinal cord are regulated at least in part by substance P-related mechanisms.

Parental use of a paediatric emergency department as an ambulatory care service

OBJECTIVE

This qualitative study explored the parental attitudes, perceptions and beliefs that play a role in the use of a tertiary paediatric emergency department (PED) when a child has a non-urgent illness.

METHOD

Semi-structured, in-depth interviews of 25 parents of children with non-urgent illnesses were conducted in the waiting room of a tertiary PED in Western Sydney in 1998. Inductive analysis was used to identify dominant themes.

RESULTS

Parents used their own system of triage to choose the appropriate service for their sick child. The perceived expertise of the tertiary PED, access and parental expectations all appeared to be major factors in parental use of a PED.

CONCLUSIONS

The parental choice to attend a PED is a dynamic, complex and unique process and the parental views that underpin this process often diverge from those of health professionals about the most 'appropriate' use of a PED.

IMPLICATIONS

A clearer understanding by health professionals of the factors influencing parental choice will promote more effective collaboration with parents and ultimately assist in the decision on the best management option for sick children.

Clinical expression of Menkes disease in a girl with X;13 translocation

Menkes disease is a rare X-linked recessive disorder of copper metabolism, characterised by progressive neurological degeneration, abnormal hair and connective tissue manifestations. We report on a girl with classic Menkes disease, carrying a de novo balanced translocation 46,X,t(X;13)(q13.3; q14.3). The translocation breakpoints at Xq13.3 and 13q14.3 coincide with the Menkes disease and Wilson disease loci, respectively.

Effects of lipoproteins from pre-eclamptic women on umbilical endothelial cell 6-oxo-prostaglandin f1alpha and endothelin 1 synthesis, and nitric oxide synthase 3 mRNA expression

In order to evaluate whether lipid abnormalities may contribute to endothelial dysfunction in pre-eclampsia, the present study examined the in vitro effects of very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL) and high-density lipoprotein (HDL), isolated from women with pre-eclampsia and matched controls, on the endothelial synthesis of 6-oxo-prostaglandin F(1alpha) (6-oxo-PGF(1alpha); a metabolite of prostacyclin) and endothelin 1, and on the expression of nitric oxide synthase 3 (NOS3) mRNA. VLDL, LDL and HDL cholesterol were isolated from 20 pre-eclamptic and 20 age- and gestation-matched normal pregnant women. The lipoproteins (50 microgram/ml) and lipoprotein-free control plasma were incubated for 1, 3 and 6 h at 37 degrees C with a human umbilical endothelial cell line. The synthesis of 6-oxo-PGF(1alpha) and endothelin 1, and NOS3 mRNA expression, were measured at each time point. VLDL from pre-eclamptic women stimulated endothelial cell 6-oxo-PGF(1alpha) synthesis to a lesser extent than that from normal pregnant women (P<0.05). LDL from women with pre-eclampsia also stimulated 6-oxo-PGF(1alpha) synthesis to a lesser extent than LDL from normal pregnant women, but the effect was less sustained. The effect of HDL from women with pre-eclampsia on 6-oxo-PGF(1alpha) synthesis was similar to that of HDL from normal pregnant women. The pre-incubation levels of lipid peroxides in VLDL and LDL were not different between the normal pregnant and pre-eclamptic women, and cannot account for the decrease in 6-oxo-PGF(1alpha) synthesis. VLDL, LDL and HDL from women with pre-eclampsia did not affect endothelial cell synthesis of endothelin 1 or expression of NOS3 mRNA differently from lipoproteins from normal pregnant women. This study suggests that VLDL, and to a lesser extent LDL, from women with pre-eclampsia could potentially contribute to the reduced systemic 6-oxo-PGF(1alpha) synthesis observed in the pre-eclamptic syndrome.

Nerve constriction in the rat: model of neuropathic, surgical and central pain

In preparation for a series of electrophysiological experiments in a model of neuropathic pain, the present spinal reflex study was done to determine the optimal time after sciatic nerve constriction in the rat for tactile allodynia and to determine also the appropriate 'control' for the nerve constriction model. Therefore, this study focused on the magnitude and time course of change in paw withdrawal threshold following unilateral sciatic nerve constriction in the rat. Male Sprague-Dawley rats (375-425g) were used. Nerve constriction was done by placing a 2 mm polyethylene cuff (PE-90) around the left sciatic nerve (n=8). A second group of rats (n=8) received unilateral sham surgery and a third group (n=8) was unoperated. The ipsi- and contralateral hind paw withdrawal thresholds in each of the 3 groups were measured using von Frey hairs. In unoperated rats, the withdrawal threshold of each of the hind paws remained unchanged at approximately 50 g throughout the entire time course of the study, which lasted 145 days. However, in cuff-implanted rats, the withdrawal threshold of the nerve-injured hind paw decreased as soon as 1 day after surgery, reached as low as 1 to 2 g by 5 days and remained low throughout the test period. Threshold in sham-operated rats showed a bilateral decrease starting on days 1-3, which stabilised at about 30 g until about day 40, after which values returned gradually toward the unoperated withdrawal thresholds. In nerve-constricted rats the withdrawal threshold of the hind paw contralateral to the cuff followed the same change seen in sham-operated rats until about day 37, after which the withdrawal threshold matched that of the cuff-implanted hind paw. The data show that the cuff-induced sciatic nerve constriction produces a sustained hypersensitivity to normally innocuous tactile sensory input and that a relatively constant ipsilateral mechanical hyperalgesia can be found from days 5-27. It is also demonstrated that the contralateral hind paw and either hind paw in sham-operated rats are inappropriate as 'controls'. The data in this study suggest that three distinct types of allodynia are expressed. Ipsilateral allodynia may be representative of a model of neuropathic pain. The contralateral allodynia may be a model of central pain, as it likely arises from changes in central sensory processing. Allodynia in sham-operated rats was also expressed bilaterally and may be a model of long-term postoperative pain.

Is proteinuric pre-eclampsia a different disease in primigravida and multigravida?

This study aimed to identify if the clinical features of proteinuric pre-eclampsia or the biochemical markers of endothelial dysfunction associated with this syndrome are altered according to parity in a direction that would suggest a different pathophysiology. Groups of 27 primigravid and 35 multigravid women with pre-eclampsia (defined as blood pressure >140/90 mmHg and 2+ proteinuria) were studied ante-partum, and at 6 weeks and 6 months post-partum. Clinical markers of severity of pre-eclampsia, including blood pressure, markers of renal, hepatic and coagulatory function, and biochemical markers of endothelial dysfunction were measured. Fetal outcome was assessed by birthweight and birthweight percentile. Ante-partum systolic blood pressure was 10 mmHg higher in the primigravida, and this difference was independent of age and anti-hypertensive medication. Analysis of systolic blood pressure before and after delivery showed the primigravid women to have elevated systolic blood pressure over the whole time period (P<0.01). The primigravid women had more severe hepatic dysfunction, with elevated aspartate aminotransferase levels, but plasma creatinine, proteinuria, platelet counts and haematocrit were similar, indicating that renal and coagulatory function and plasma volume were affected to the same extent in the two groups and were independent of parity. Birthweight was similar in the two groups, and the percentage of infants weighing less than the 10th centile for gestation was also similar. Biochemical markers of endothelial dysfunction, assessed by measuring the urinary prostacyclin metabolite 2, 3-dinor-6-oxo-prostaglandin F(1alpha) and plasma endothelin 1, did not differ according to parity. There were no differences in a number of other biochemical markers of pre-eclampsia, including plasma albumin, uric acid, triacylglycerol, and total, low-density lipoprotein and high-density lipoprotein cholesterol. Basophil, monocyte and lymphocyte counts were elevated before delivery in primigravid women with pre-eclampsia. The differences in lymphocyte counts persisted post-partum. Further studies are required to clarify the role, if any, of monocytes, basophils and lymphocytes in the pathophysiology of pre-eclampsia. In conclusion, the elevated systolic blood pressure and raised aspartate aminotransferase levels observed in primigravida suggest a more severe form of pre-eclampsia. The lack of differences in birthweight and other biochemical and endothelial markers of severity of pre-eclampsia do not suggest a different pathophysiology; however, the persistently higher white cell counts in the primigravid pre-eclamptics are of interest, and might reflect differences in immune responses in the two groups. We suggest that studies of the pathophysiology of pre-eclampsia should include multigravida, as long as there is adequate post-partum follow-up to exclude underlying disease.

Does a predisposition to the metabolic syndrome sensitize women to develop pre-eclampsia?

OBJECTIVE

This study aimed to identify those factors in the non-pregnant state that distinguished women who developed pre-eclampsia from those who had normotensive pregnancies.

DESIGN AND SETTING

This was a retrospective analysis of anthropometry, blood pressure, biochemical and haematological variables in 62 women with pre-eclampsia and 84 normotensive pregnant women who took part in studies of the pathophysiology of pre-eclampsia. Pregnant volunteers were seen, after admission to hospital or in the outpatient clinic, and followed-up at 6 weeks and 6 months post-partum in the outpatient clinic or their home. Participants Proteinuric pre-eclampsia was defined as blood pressure > or = 140/90 mmHg with proteinuria of at least 300 mg/24 h after 20 weeks gestation, in women with no history of hypertension and whose blood pressure returned to normal levels by 6 months post-partum. Normotensive pregnancy was defined as blood pressure < 130/90 mmHg without proteinuria.

MAIN OUTCOME MEASURES

The primary outcome measures were blood pressure, body mass index (BMI), triglycerides, total cholesterol, low density lipoprotein (LDL) and high density lipoprotein cholesterol and markers of severity of pre-eclampsia.

RESULTS

Regardless of parity, women with pre-eclampsia had elevated BMI before, during and after pregnancy compared with women who had normotensive pregnancies. Triglycerides were significantly elevated in women who had pre-eclampsia both before and after delivery, while total and LDL cholesterol were elevated significantly at both visits after delivery. Systolic and diastolic blood pressure, which by definition were elevated antepartum in women with pre-eclampsia, remained higher at post-partum visits compared with women who had normotensive pregnancies. Women with pre-eclampsia reported a greatly increased frequency of both maternal hypertension and pre-eclampsia. Markers of severity of pre-eclampsia, which normalized by 6 months postpartum, included plasma creatinine, uric acid, albumin, endothelin 1 and urinary protein, 2,3, dinor-6-keto-PGF1alpha, blood platelet and neutrophil counts.

CONCLUSION

The relative elevation of blood pressure, BMI and lipids in the non-pregnant state are features of the metabolic syndrome and may be important sensitizing factors contributing to the pathogenesis of pre-eclampsia. A familial predisposition to pre-eclampsia may operate partly through these mechanisms.

Health promoting schools: issues and future directions for Australia and the Asia Pacific Region

This paper sets out to trace the development of health promoting schools in Australia and the Asia Pacific Region. An overview of conceptual frameworks pertinent to promoting health in school is presented, together with a justification for a focus on schools as settings for health. The challenge ahead for school communities is to move from the simple classroom-based topic focused old style health education, to the whole settings approach and the broad-ranging, comprehensive collection of actions that make up this wider view.