Regional membrane phospholipid alterations in Alzheimer's disease

Regional levels of membrane phospholipids [phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylcholine (PC)] were measured in the brain of Alzheimer's disease (AD) and control subjects. The levels of PE-derived and PI-derived total fatty acids were significantly decreased in the hippocampus of AD subjects. Here significant decreases were found in PE-derived stearic, oleic and arachidonic and docosahexaenoic acids, and in PI-derived oleic and arachidonic acids. In the inferior parietal lobule of AD subjects, significant decreases were found only in PE and those decreases were contributed by stearic, oleic and arachidonic acids. In the superior and middle temporal gyri and cerebellum of AD subjects, no significant decreases were found in PC-, PE- and PI-derived fatty acids. The decrease of PE and PI, which are rich in oxidizable arachidonic and docosahexaenoic acids, but not of PC, which contains lesser amounts of these fatty acids, suggests a role for oxidative stress in the increased degradation of brain phospholipids in AD.

The postnatal management of hydronephrosis diagnosed by prenatal ultrasound

A total of 112 patients (142 kidneys) presented with hydronephrosis consistent with ureteropelvic junction obstruction that had been diagnosed by prenatal ultrasound. The kidneys were classified as having poor, moderate or good function based on isotope imaging at 3 months after birth. Of 9 kidneys that showed poor function 3 recovered sufficient function on pigtail drainage to justify preservation and these patients underwent pyeloplasty. Of 27 kidneys with moderate function 23 also underwent pyeloplasty and 14 of these demonstrated improvement in function postoperatively. Of the 100 kidneys in the good function group that were followed conservatively 23 underwent pyeloplasty during followup primarily because of an observed decrease in function. We propose that there is no indication for immediate pyeloplasty in infants with prenatally diagnosed hydronephrosis who demonstrate good function postnatally.

The characteristics of primary vesico-ureteric reflux in male and female infants with pre-natal hydronephrosis

OBJECTIVE

To examine the characteristics of primary vesico-ureteric reflux (VUR) in young infants following prenatal hydronephrosis.

PATIENTS AND METHODS

The study comprised 155 consecutive infants with VUR detected at a mean age of 8.7 weeks (SD 6.3). Reflux units (n = 236) were analysed for relationships between gender, severity of reflux, exposure to urinary tract infection (UTI) and the presence of focal and generalized types of kidney damage on imaging. Bladder wall thickness (from ultrasonography) was examined in comparison with a further group of 29 males without VUR.

RESULTS

Male infants predominated (117 of 155, 75%); bilateral VUR affected the same proportion (52%) of males and females. Most kidneys exposed to VUR (158 of 236. 67%) were normal and of the 78 abnormal kidneys (57 without UTI), 53 showed generalized damage (only eight exposed to UTI) and 71 (91%) were associated with severe (grades IV and V) reflux that predominantly affected males (P < 0.001). Grade V reflux was almost exclusively a male disorder. Most female units (45 of 58, 78%) compared with 46% (82/178) of male units had mild (grades I to III) reflux that was independently associated with normal kidneys. The mean bladder wall thickness was significantly greater for males with VUR than for females with VUR and for males without VUR.

CONCLUSIONS

Two distinct but not exclusive patterns of VUR were identified: (i) mild reflux associated with normal kidneys that affected most females and a proportion of males; (ii) severe reflux combined with kidney damage, most likely fetal in origin, that is almost exclusively a male disorder.

Comparison of two standard chemotherapy regimens for good-prognosis germ-cell tumours: a randomised trial. Australian and New Zealand Germ Cell Trial Group

BACKGROUND

Most patients with metastatic germ-cell tumours are cured with chemotherapy. However, the optimum chemotherapy regimen is uncertain, and there is variation in international practice. We did a multicentre randomised trial to compare two standard chemotherapy regimens for men with good-prognosis germ-cell tumours.

METHODS

Good prognosis was defined by modified Memorial Sloan-Kettering criteria. The first regimen (regimen A) was based on treatment recommendations from Indiana University and comprised three cycles of 20 mg/m2 cisplatin on days 1-5, 100 mg/m2 etoposide on days 1-5, and 30 kU bleomycin on days 1, 8, and 15, repeated every 21 days. The second regimen (regimen B) was based on the control regimen of a published randomised clinical trial and comprised four cycles of 100 mg/m2 cisplatin on day 1, 120 mg/m2 etoposide on days 1-3, and 30 kU bleomycin on day 1, repeated every 21 days. The primary outcome measure was overall survival. Analysis was by intention to treat.

FINDINGS

166 patients were randomised, 83 to each regimen. The trial was stopped when the second planned interim analysis met predefined stopping rules. The median follow-up was 33 months. Overall survival was substantially better with regimen A (three vs 13 deaths, hazard ratio 0.22 [95% CI 0.06-0.77], p=0.008). This difference was due to deaths from cancer (one vs nine), and not deaths from treatment (two vs two) and remained significant after adjustment for other prognostic factors (0.25 [0.07-0.88], p=0.03).

INTERPRETATION

In men with good-prognosis germ-cell tumours, the regimen developed at Indiana University is superior to the alternative regimen studied in this trial. The lower total dose and dose-intensity of bleomycin and the lower dose-intensity of etoposide in regimen B could be responsible for the worse outcome.

The Colon Health and Life-Long Exercise Change trial: a randomized trial of the National Cancer Institute of Canada Clinical Trials Group

Background

Observational studies indicate that physical activity (pa) is strongly associated with improved disease outcomes in colon cancer survivors, but a randomized controlled trial is needed to determine whether the association is causal and whether new policies to promote exercise are justified.

Purpose

The co.21 Colon Health and Life-Long Exercise Change (challenge) trial undertaken by the National Cancer Institute of Canada Clinical Trials Group (ncic ctg) is designed to determine the effects of a structured pa intervention on outcomes for survivors of high-risk stage ii or iii colon cancer who have completed adjuvant therapy within the previous 2–6 months.

Methods

Trial participants (n = 962) will be stratified by centre, disease stage, body mass index, and performance status, and will be randomly assigned to a structured pa intervention or to general health education materials. The pa intervention will consist of a behavioural support program and supervised pa sessions delivered over a 3-year period, beginning with regular face-to-face sessions and tapering to less frequent face-to-face or telephone sessions. The primary endpoint is disease-free survival. Important secondary endpoints include multiple patient-reported outcomes, objective physical functioning, biologic correlative markers, and an economic analysis.

Summary

Cancer survivors and cancer care professionals are interested in the potential role of PA to improve multiple disease-related outcomes, but a randomized controlled trial is needed to provide compelling evidence to justify changes in health care policies and practice.

Urodynamic patterns in infants with normal lower urinary tracts or primary vesico-ureteric reflux

OBJECTIVE

To compare bladder function in infants with primary vesico-ureteric reflux (VUR) and those with normal lower urinary tracts.

PATIENTS AND METHODS

The study comprised 42 patients (36 males) with VUR (grades III to V) and 21 (16 males) without VUR (mean age in both groups, 6 months). Intravesical catheters were placed suprapubically under general anaesthesia and, after at least 24 h, natural-tilling urodynamics were monitored for three or more filling and voiding cycles.

RESULTS

Various urodynamics patterns were defined: for infants without VUR these were either normal or normal-immature (discoordinated micturition) and none showed features indicating abnormal bladder function. By comparison, 24 of 42 infants with VUR showed abnormal urodynamic patterns (57%, 95% confidence interval 41% to 72%, P < 0.001). Seven (17%) were defined as unstable with small voided volumes, five (12%) had inadequate voiding dynamics, 10 (24%) showed a markedly dyssynergic pattern and two (5%) had obstructive patterns. The unstable, inadequate and obstructive patterns occurred only in boys. Detrusor activity during the filling phase occurred in 14 infants (13 boys) with VUR and in only one without VUR, when it was trivial. Post-void residual volumes of > 30% capacity were seen only in the VUR group (in 24 patients). There were 18 infants with VUR that showed the normal or immature urodynamics patterns, but for the 14 males the voiding pressures were higher than for those without VUR (mean maximum detrusor pressure, 161 and 117 cmH2O, respectively: P < 0.02).

CONCLUSIONS

There is an association between abnormal urodynamic variables and a diagnosis of primary VUR in young infants (notably males) that may have important implications for concepts about the genesis and persistence of VUR.

Antenatal diagnosis of posterior urethral valves

The antenatal histories of 42 patients with posterior urethral valves diagnosed between June 1987 and September 1990 were reviewed. The mothers of all patients had at least one ultrasound scan during pregnancy. Despite this, fetal uropathy was diagnosed in only 19 cases. The remaining 23 undiagnosed children presented acutely, all within the first 6 months of life. In 33 of 36 pregnancies scanned before 24 weeks' gestation, fetal urological pathology was undetected. Mean plasma creatinine (pCr) at presentation in the group antenatally diagnosed was 139 mumol/l and in those presenting acutely was 238 mumol/l. All pCr analysed were taken after at least 48 h of life. Renal function as measured by follow-up pCr was better in the antenatally diagnosed group during the first year of life. It would appear that a routine second ultrasound scan at 26 weeks' gestation or later would reveal more cases of posterior urethral valves and this information may improve the outcome in terms of renal function.

Central leptin gene therapy suppresses body weight gain, adiposity and serum insulin without affecting food consumption in normal rats: a long-term study

The weight-reducing effects of leptin are predominantly mediated through the hypothalamus in the brain. Gene therapy strategies designed for weight control have so far tested the short-term effect of peripherally delivered viral vectors encoding the leptin gene. In order to circumvent the multiple peripheral effects of hyperleptinemia and to overcome the age-related development of leptin resistance due to multiple factors, including defective leptin transport across the blood brain barrier, we determined whether delivery of viral vectors directly into the brain is a viable therapeutic strategy for long-term weight control in normal wild-type rats. A recombinant adeno-associated virus (rAAV) vector encoding rat leptin (Ob) cDNA was generated (rAAV-betaOb). When administered once intracerebroventricularly (i.c.v.), rAAV-betaOb suppressed the normal time-related weight gain for extended periods of time in adult Sprague-Dawley rats. The vector expression was confirmed by immunocytochemical localization of GFP and RT-PCR analysis of leptin in the hypothalamus. This sustained restraint on weight gain was not due to shifts in caloric consumption because food-intake was similar in rAAV-betaOb-treated and rAAV-GFP-treated control rats throughout the experiment. Weight gain suppression, first apparent after 2 weeks, was a result of reduced white fat depots and was accompanied by drastically reduced serum leptin and insulin concentrations in conjunction with normoglycemia. Additionally, there was a marked increase in uncoupling protein-1 (UCP1) mRNA expression in brown adipose tissue, thereby indicating increased energy expenditure through thermogenesis. Seemingly, a selective enhancement in energy expenditure following central delivery of the leptin gene is a viable therapeutic strategy to control the age-related weight gain and provide protection from the accompanying multiple peripheral effects of hyperleptinemia and hyperinsulinemia.

The relationship between early renal status, and the resolution of vesico-ureteric reflux and bladder function at 16 months

OBJECTIVE

To examine, in infants presenting with vesico-ureteric reflux (VUR), the relationship between the presence of initial renal abnormalities with the outcome of VUR and bladder function at 16 months of age.

PATIENTS AND METHODS

The study group comprised 40 infants (32 boys) presenting consecutively (29 after prenatal detection) with VUR grade III or greater (bilateral in 29) on the initial micturating cystogram (median age 8 weeks). The initial presence of abnormal kidneys was determined from isotopic renography and/or ultrasonography. These data were correlated with the outcome of VUR, from direct isotope cystography, and bladder function assessed by natural filling urodynamics, examined at age 16 months (mean 16.4 months, SD 2.1).

RESULTS

Three groups were identified. Group 1 (eight boys and six girls) had normal kidneys bilaterally; initially grade III VUR was common. At 16 months bladder function was normal in 10 children and none had VUR (complete resolution). Group 2 (14 boys and two girls) had unilateral renal abnormalities; initially VUR was predominantly grade IV or grade V. At 16 months bladder function was normal in eight children and VUR resolved in eight, five of these with normal bladder function. Group 3 (10 boys) had bilateral renal abnormalities. Initially grade V VUR predominated; at 16 months the bladder function was normal in only one, and in the rest the emptying dynamics were abnormal. All 10 boys had persisting VUR (no resolution).

CONCLUSIONS

In infants with moderate or severe VUR, resolution at 16 months old is associated with normal kidneys in a similar proportion of boys and girls. Resolution also correlates well with normal bladder function. Presentation in infancy with bilateral abnormal kidneys, associated with severe VUR in boys, is a poor prognostic sign for the early outcome of VUR and for bladder function.

Clinical outcome and management of prenatally diagnosed primary megaureters

The objective of this study was to evaluate the clinical outcome of infants diagnosed perinatally with primary obstructive megaureter, and to determine which anatomical and physiological indexes best predict such outcome. A total of 67 megaureters thought to be due to primary vesicoureteral junction obstruction was detected in 53 newborns as a result of prenatally diagnosed hydronephrosis or hydroureteronephrosis. These patients were followed nonoperatively using periodic ultrasound and 99mtechnetium-diethylenetriaminepentaacetic acid (Tc-DTPA) renal scans. After a mean followup period of 3.1 years 23 dilated ureters (34%) spontaneously resolved while 33 (49%) persisted. Repair was performed on 11 megaureters (17%) because of breakthrough urinary infections in 3 and deteriorating renal function in 8. Postoperatively, all renal units showed improved drainage on 99mTc-DTPA renal scan, while half of those with decreased renal function regained the lost function. None had further deterioration in renal function. Of the clinical indexes studied ultrasonographic ureteral diameter (less than 6 mm. good, greater than 10 mm. poor prognosis) and drainage on 99mTc-DTPA renal scan correlated best with outcome. We conclude that the majority of primary megaureters detected in the perinatal period can be followed conservatively using periodic ultrasound and 99mTc-DTPA renal scans. Relatively few cases required surgical intervention and those at risk were identifiable by a diameter greater than 10 mm. and poor drainage on 99mTc-DTPA renal scan.

Fetal urine analysis for the assessment of renal function in obstructive uropathy

OBJECTIVES

The assessment of fetal renal function plays a key role in the evaluation of posterior urethral valve obstruction cases. The aim of our study was to determine the value of several urinary compounds, including beta 2-microglobulin, N-acetyl-beta-D-glucosaminidase, and microalbumin in the assessment of prenatal renal function in cases of posterior urethral valve and their potential role in the selection of such cases for in utero shunting.

STUDY DESIGN

A range of urinary compounds was measured, including beta 2-microglobulin, N-acetyl-beta-D-glucosaminidase, and microalbumin in 25 cases of posterior urethral valve obstruction. These cases were divided into four groups based on outcome. The Mann-Whitney test and analysis of covariance were used.

RESULTS

Sodium, calcium, and beta 2-microglobulin were the best predictors for fetal survival. beta 2-Microglobulin values > 13 mg/L were almost invariably associated with fatal outcome.

CONCLUSION

The estimation of beta 2-microglobulin may help in counseling parents and in selecting cases for in utero shunting.

Dose-dependent effects of central leptin gene therapy on genes that regulate body weight and appetite in the hypothalamus

We have examined the dose-dependent effects and central action of intraventricular administration of a recombinant adeno-associated virus encoding rat leptin (rAAV-leptin) in suppressing body weight (BW) gain in adult female rats. A low dose of rAAV-leptin (5x10(10) particles) suppressed weight gain (15%) without changing daily food intake (FI), but a twofold higher dose decreased BW by 30% along with a reduction in daily FI. Reduced BW was due to a loss in body adiposity because serum leptin was reduced. Serum insulin levels were decreased (96%) by only the high dose along with a slight reduction in glucose. Uncoupling protein-1 (UCP-1) mRNA expression in brown adipose tissue (BAT), reflecting energy expenditure through thermogenesis, was upregulated to the same magnitude by the two rAAV-leptin doses. We analyzed by in situ hybridization the expression in the hypothalamus of genes encoding the appetite-regulating neuropeptides. Only the high dose decreased expression of neuropeptide Y (NPY), the orexigenic peptide, and increased proopiomelanocortin (POMC), precursor of the an orexigenic peptide, alpha-MSH. Our studies show for the first time that increased availability of leptin within the hypothalamus through central leptin gene therapy dose-dependently decreases weight gain, adiposity, and serum insulin by increasing energy expenditure and decreasing FI. The decrease in FI occurs only when NPY is reduced and alpha-MSH is increased in the hypothalamus by the high dose of rAAV-leptin. Delivery of the leptin gene centrally through rAAV vectors is a viable therapeutic modality for long-term control of weight and metabolic hormones.

Abdominal sensitivity in the first year of life: comparison of infants with and without prenatally diagnosed unilateral hydronephrosis

There are few studies on visceral pain in infants, despite its clinical importance. We have used the abdominal skin reflex (ASR) to measure changes in abdominal sensitivity in the presence of visceral pathology in infants. The reflex was elicited by applying calibrated von Frey hairs to each side of the abdomen and the mechanical threshold and the degree of reflex radiation as denoted by hip flexion were measured. The developmental progression of ASR properties during the first year of life was studied in a cross-sectional sample of healthy infants ranging from 30 to 95 weeks postconceptional age (PCA). These properties were compared to those in infants with unilateral hydronephrosis (UH) using a blinded protocol. Infants with UH were studied at their first outpatient appointment after birth, and postoperatively following surgery if this was indicated. The investigators were blinded to laterality and severity of hydronephrosis until data were analysed, or until surgery. A total of 30 patients with UH and 77 healthy infants were included in the study. In 21 (70%) patients, the side of hydronephrosis had a significantly lower ASR threshold than the contralateral side of the abdomen. There was a significant increase in reflex threshold and decrease in reflex radiation with increasing PCA in control infants. However, in UH infants, this relationship did not exist, even on the unaffected side of the abdomen.Our results show that infants with prenatally diagnosed UH demonstrate increased abdominal sensitivity compared with control infants. Using the ASR, we have provided the first evidence of referred visceral hypersensitivity in infants.

Mice lacking beta-adrenergic receptors have increased bone mass but are not protected from deleterious skeletal effects of ovariectomy

Activation of beta2-adrenergic receptors inhibits osteoblastic bone formation and enhances osteoclastic bone resorption. Whether beta-blockers inhibit ovariectomy-induced bone loss and decrease fracture risk remains controversial. To further explore the role of beta-adrenergic signaling in skeletal acquisition and response to estrogen deficiency, we evaluated mice lacking the three known beta-adrenergic receptors (beta-less). Body weight, percent fat, and bone mineral density were significantly higher in male beta-less than wild-type (WT) mice, more so with increasing age. Consistent with their greater fat mass, serum leptin was significantly higher in beta-less than WT mice. Mid-femoral cross-sectional area and cortical thickness were significantly higher in adult beta-less than WT mice, as were femoral biomechanical properties (+28 to +49%, P < 0.01). Young male beta-less had higher vertebral (1.3-fold) and distal femoral (3.5-fold) trabecular bone volume than WT (P < 0.001 for both) and lower osteoclast surface. With aging, these differences lessened, with histological evidence of increased osteoclast surface and decreased bone formation rate at the distal femur in beta-less vs. WT mice. Serum tartrate-resistance alkaline phosphatase-5B was elevated in beta-less compared with WT mice from 8-16 wk of age (P < 0.01). Ovariectomy inhibited bone mass gain and decreased trabecular bone volume/total volume similarly in beta-less and WT mice. Altogether, these data indicate that absence of beta-adrenergic signaling results in obesity and increased cortical bone mass in males but does not prevent deleterious effects of estrogen deficiency on trabecular bone microarchitecture. Our findings also suggest direct positive effects of weight and/or leptin on bone turnover and cortical bone structure, independent of adrenergic signaling.

Fetal telemedicine: six month pilot of real-time ultrasound and video consultation between the Isle of Wight and London

DESIGN

Prospective audit of first six months.

SETTING

Referral from a district general hospital on the Isle of Wight to a comprehensive tertiary referral service, the Centre for Fetal Care at Queen Charlotte's Hospital 120 km away in London.

PARTICIPANTS

Women whose pregnancy was suspected, or at risk, of fetal abnormality.

INTERVENTIONS

Remote consultation by transmitting ultrasound and video in real-time over ISDN 30 telephone lines. Contemporaneous questionnaire to referring practitioner and patient.

MAIN OUTCOME MEASURES

Frequency, indication, technical success and duration of consultation. Qualitative and semi-quantitative image quality. Effect of teleconsultation on need for physical referral.

RESULTS

Twenty-nine women underwent 39 teleconsultations, and image quality was sufficient for diagnosis in all but one. Fetal abnormalities were present in 76%. Referral in person was required for only four women, significantly fewer than the 13 the referring hospital indicated would have been physically referred in the absence of this service (P < 0.001). Most mothers were counselled by the specialist "face-to-face' over the link, and 80% felt teleconsultation reduced their anxiety.

CONCLUSIONS

A fetal telemedicine service is technically and clinically feasible. This demonstration suggests that such a service reduces the need for physical referral while increasing the rate of consultation, allowing better selection of patients who might benefit from referral. Further evaluation in a variety of clinical settings is now indicated, along with cost-benefit analysis.

A meta-analysis of two randomised trials of early chemotherapy in asymptomatic metastatic colorectal cancer

This report constitutes a prospectively planned meta-analysis combining two almost identical trials undertaken in Australasia and Canada to study the effect of starting chemotherapy immediately in asymptomatic patients with metastatic colorectal cancer. Patients (n=168) were randomised to receive either immediate or delayed treatment (at onset of predefined symptoms). Australasian patients received either weekly 5-fluorouracil and leucovorin (500 and 20 mg m(-2), respectively) (n=59) or the daily x 5 Mayo Clinic schedule (425 and 20 mg m(-2), respectively) (n=42). Canadian patients were treated with the Mayo schedule (n=67). Otherwise, the two studies were almost identical in design and each used the European Organisation for the Research and Treatment of Cancer (EORTC) QLQ-C30 instrument for measuring quality of life (QoL). Treatment was continued until 6 months had elapsed or disease progression occurred. Low accrual led to trial suspension before the predetermined sample size for either study was reached. Median survival was not significantly better with immediate treatment (median 13.0 vs 11.0 months; hazard ratio, 1.15; 95% confidence interval (CI) 0.79-1.72; P=0.49). There was no statistically significant difference in progression-free survival (time from randomisation until first evidence of progression after chemotherapy, 10.2 vs 10.8 months; hazard ratio, 1.08; 95% CI 0.71-1.64; P=0.73). There was no difference in overall QoL or its individual domains between the two treatment strategies at baseline or at any subsequent time point. Early treatment of asymptomatic patients with metastatic colorectal cancer did not provide a survival benefit or improved QoL compared to withholding treatment until symptoms occurred.

Somatostatin receptor expression, tumour response, and quality of life in patients with advanced hepatocellular carcinoma treated with long-acting octreotide

Octreotide may extend survival in hepatocellular carcinoma (HCC). Forty-one per cent of HCCs have high-affinity somatostatin receptors. We aimed to determine the feasibility, safety, and activity of long-acting octreotide in advanced HCC; to identify the best method for assessing somatostatin receptor expression; to relate receptor expression to clinical outcomes; and to evaluate toxicity. Sixty-three patients with advanced HCC received intramuscular long-acting octreotide 20 mg monthly until progression or toxicity. Median age was 67 years (range 28–81 years), male 81%, Child–Pugh A 83%, and B 17%. The aetiologies of chronic liver disease were alcohol (22%), viral hepatitis (44%), and haemochromatosis (6%). Prior treatments for HCC included surgery (8%), chemotherapy (2%), local ablation (11%), and chemoembolisation (6%). One patient had an objective partial tumour response (2%, 95% CI 0–9%). Serum alpha-fetoprotein levels decreased more than 50% in four (6%). Median survival was 8 months. Thirty four of 61 patients (56%) had receptor expression detected by scintigraphy; no clear relationship with clinical outcomes was identified. There were few grade 3 or 4 toxicities: hyperglycaemia (8%), hypoglycaemia (2%), diarrhoea (5%), and anorexia (2%). Patients reported improvements in some symptoms, but no major changes in quality of life were detected. Long-acting octreotide is safe in advanced HCC. We found little evidence of anticancer activity. A definitive randomised trial would identify whether patients benefit from this treatment in other ways.

Long-term differential modulation of genes encoding orexigenic and anorexigenic peptides by leptin delivered by rAAV vector in ob/ob mice. Relationship with body weight change

We investigated the long-term effects of physiological levels of leptin produced by gene therapy on body weight (BW) and expression of genes that encode orexigenic and anorexigenic peptides in the hypothalamus. Recombinant adeno-associated viral vector (rAAV), a non-pathogenic and non-immunogenic vector, encoding leptin (betaOb) was generated and administered iv to ob/ob mice lacking endogenous leptin. Whereas the lowest dose of rAAV-betaOb (6x10(9) particles) was ineffective, the middle dose (6x10(10) particles) curbed BW gain without affecting food consumption for 75 days of observation. A ten-fold higher dose (6x10(11) particles) resulted in increased blood leptin levels and suppressed both BW gain and food consumption throughout the duration of the experiment. rAAV-betaOb doses that either curbed BW without affecting food consumption or evoked BW loss and reduced food intake, decreased the expression of genes encoding the orexigenic peptides, neuropeptide Y and agouti-related peptide in the ARC, and the two doses were equally effective. Concomitantly, the expression of genes encoding the anorexigenic peptide, alpha-melanocyte stimulating hormone and cocaine-and-amphetamine regulatory transcript, was augmented with the latter gene displaying a dose-dependant response. These results document the efficacy of delivering biologically active leptin for extended periods by an iv injection of rAAV-betaOb and show that physiological leptin concentrations simultaneously exert a tonic inhibitory effect on orexigenic and a stimulatory effect on anorexigenic signaling in the hypothalamus. This intricate dynamic interplay induced by leptin regulates BW with or without an effect on food intake in leptin-deficient ob/ob mice. Further, these results suggest that gene therapy is an effective mode of delivery to the hypothalamus of those therapeutic proteins that cross the blood-brain barrier to ameliorate neuroendocrine disorders.

Neuropeptide Y counteracts the anorectic and weight reducing effects of ciliary neurotropic factor

Ciliary neurotrophic factor (CNTF), a cytokine of the interleukin-6 superfamily, has been shown to induce hypophagia and weight loss. Neuropeptide Y (NPY) and orexin are potent orexigenic signals in the hypothalamus. Anorexia, normally seen in response to infection, injury and inflammation, may result from diminished hypothalamic orexigenic signalling caused by persistently elevated cytokines, including CNTF. To test this hypothesis, we first examined the effects of chronic intracerebroventricular (i.c.v.) infusion of CNTF for 6-7 days on food intake and body weight as well as hypothalamic NPY and orexin gene expression in male rats. Subsequently, the effectiveness of NPY replacement to counteract the effects of CNTF by coinfusion of NPY and CNTF was evaluated. Chronic i.c.v. infusion of CNTF (2.5 microg/day) reduced body weight (14.3% vs control) at the end of 7 days. Food intake remained suppressed for 5 days postinfusion and subsequently gradually returned to the control range by day 7. Serum leptin concentrations in these rats were in the same range seen in control rats. Chronic i.c.v. infusion of higher doses of CNTF (5.0 microg/day) produced sustained anorexia and body weight loss (29% vs controls) through the entire duration of the experiment. This severe anorexia was accompanied by markedly suppressed serum leptin concentrations. Furthermore, CNTF infusion alone significantly reduced hypothalamic NPY gene expression (P < 0. 05) without affecting orexin gene expression. As expected, in fusion of NPY alone (18 microg/day) augmented food intake (191.6% over the initial control, P < 0.05) and produced a 25.1% weight gain in conjunction with a 10-fold increase in serum leptin concentrations at the end of the 7-day period. Interestingly, coinfusion of this regimen of NPY with the highly effective anorectic and body reducing effects of CNTF (5.0 microg/day) not only prevented the CNTF-induced anorexia and weight loss, but also normalized serum leptin concentrations and hypothalamic NPY gene expression. These results demonstrate that chronic central infusion to produce a persistent elevation of the cytokine at pathophysiological levels (a situation that may normally manifest during infection, injury and inflammation) produced severe anorexia and weight loss in conjunction with reduction in both serum leptin concentrations and hypothalamic NPY gene expression. Reinstatement of hypothalamic NPY signalling by coinfusion of NPY counteracted these CNTF-induced responses.

Chemical vapour deposition synthetic diamond: materials, technology and applications

Substantial developments have been achieved in the synthesis of chemical vapour deposition (CVD) diamond in recent years, providing engineers and designers with access to a large range of new diamond materials. CVD diamond has a number of outstanding material properties that can enable exceptional performance in applications as diverse as medical diagnostics, water treatment, radiation detection, high power electronics, consumer audio, magnetometry and novel lasers. Often the material is synthesized in planar form; however, non-planar geometries are also possible and enable a number of key applications. This paper reviews the material properties and characteristics of single crystal and polycrystalline CVD diamond, and how these can be utilized, focusing particularly on optics, electronics and electrochemistry. It also summarizes how CVD diamond can be tailored for specific applications, on the basis of the ability to synthesize a consistent and engineered high performance product.

Post-natal management of antenatally detected, bilateral hydronephrosis

26 children, with antenatally detected, isolated, bilateral hydronephrosis (thus consistent with pelvi-ureteric junction obstruction), were investigated for up to 7 years. The aim was to avoid operation. 34 kidneys were never operated on. Despite initially often severe hydronephrosis and poor isotope wash-out on the renogram, half of the kidneys improved or even normalized during follow-up. The final glomerular filtration rate (GFR) was always normal or almost normal. 18 kidneys came to surgery, because of poor filtration, symptoms or social reasons. At the end of the follow-up, GFR was normal in all but 2 kidneys. In a subgroup of the kidneys, with initially severe reduction in filtration, half were operated on and half were not; at the end, the GFR was normal in all of the non-operated kidneys (and in all but 1 of the operated kidneys). Total GFR was at the end normal or almost normal also in the children with persistingly filtration-reduced kidneys (always unilaterally), because of compensation by the contralateral, although hydronephrotic kidney. Thus, in this study the renographic parameters were not very helpful in predicting the prognosis. There was no consistent difference between operative and non-operative treatments on final filtration. Also hydronephrotic kidneys possessed a substantial capacity for contralateral compensation. It is concluded that the initial approach to bilateral, antenatally diagnosed hydronephrosis may safely be non-operative. This allows time for the clear expression of sustained impairment of renal filtration requiring surgical intervention.

Adenocarcinoma of the urinary bladder

We report 40 patients seen over a 15-year period with a histological diagnosis of adenocarcinoma of the bladder; 18 patients had primary adenocarcinoma of the bladder, arising either from the urachus or from glandular metaplasia of the urothelium, and the other 22 had secondary lesions representing invasion from adjacent structures, notably prostate, colon and ovary. In this latter group symptoms related to the primary lesion were variable. The distinction between primary and secondary neoplasm is an important one and was rarely made on the basis of endoscopic or clinical findings alone. Urachal tumours were more common in females, whereas primary and secondary vesical adenocarcinomas were more common in males. The urachal tumours also occurred in a younger age group. Most of the adenocarcinomas, urachal or primary, were already advanced at the time of diagnosis. All tumours were palpable bimanually after resection and were at least T2 or T3. In the urachal carcinomas the results of partial cystectomy were disappointing because of the high rate of local recurrence and death from metastases. Primary non-urachal vesical adenocarcinoma carried an even poorer prognosis if non-radical surgery was carried out. The mean survival was 13 months. Radiotherapy was not effective in urachal and primary adenocarcinomas as these tumours are generally radioresistant. The treatment of secondary adenocarcinoma was governed by the primary site of the tumour. Radical surgery combined with chemotherapy and radiotherapy appeared to give the longest survival in the colonic tumours. Patients with prostatic cancer had a poorer survival rate than those with the same stage tumour but without bladder involvement, with renal failure secondary to obstructive uropathy being the commonest cause of death.

Antenatal diagnosis of renal pelvic dilatation--the natural history of conservative management

Seventy children with an antenatal diagnosis of unilateral renal pelvic dilatation underwent Tc 99 m DTPA diuretic renograms. There were 16 kidneys with moderate function, and 54 with good function, 31 underwent pyeloplasty, all had a renal pelvis greater than 12 mm diameter on ultrasound. Thirty nine children with good function were treated conservatively. Long term follow up has demonstrated that conservative management for PUJ dilatation with a good functioning kidney may be justified but a randomised control study is required.