Neuropeptide coding of sympathetic preganglionic neurons; focus on adrenally projecting populations

Chemical coding of sympathetic preganglionic neurons (SPN) suggests that the chemical content of subpopulations of SPN can define their function. Since neuropeptides, once synthesized are transported to the axon terminal, most demonstrated chemical coding has been identified using immunoreactive terminals at the target organ. Here, we use a different approach to identify and quantify the subpopulations of SPN that contain the mRNA for pituitary adenylate cyclase activating polypeptide (PACAP) or enkephalin. Using double-labeled immunohistochemistry combined with in situ hybridization (ISH) we firstly identified the distribution of these mRNAs in the spinal cord and determined quantitatively, in Sprague-Dawley rats, that many SPN at the T4-T10 spinal level contain preproPACAP (PPP+, 80 ± 3%, n=3), whereas a very small percentage contain preproenkephalin (PPE+, 4 ± 2%, n=4). A similar neurochemical distribution was found at C8-T3 spinal level. These data suggest that PACAP potentially regulates a large number of functions dictated by SPN whereas enkephalins are involved in few functions. We extended the study to explore those SPN that control adrenal chromaffin cells. We found 97 ± 5% of adrenally projecting SPN (AP-SPN) to be PPP+ (n=4) with only 47 ± 3% that were PPE+ (n=5). These data indicate that adrenally projecting PACAPergic SPN regulate both adrenal adrenaline (Ad) and noradrenaline (NAd) release whereas the enkephalinergic SPN subpopulation must control a (sub) population of chromaffin cells - most likely those that release Ad. The sensory innervation of the adrenal gland was also determined. Of the few adrenally projecting dorsal root ganglia (AP-DRG) observed, 74 ± 12% were PPP+ (n=3), whereas 1 ± 1% were PPE+ (n=3). Therefore, if sensory neurons release peptides to the adrenal medulla, PACAP is most likely involved. Together, these data provide a neurochemical basis for differential control of sympathetic outflow particularly that to the adrenal medulla.

Activin signaling functions upstream of Gbb to regulate synaptic growth at the Drosophila neuromuscular junction

Activins are members of the TGF-ss superfamily of secreted growth factors that control a diverse array of processes in vertebrates including endocrine function, cell proliferation, differentiation, immune response and wound repair. In Drosophila, the Activin ligand Dawdle (Daw) has been shown to regulate several aspects of neuronal development such as embryonic axonal pathfinding, neuroblast proliferation in the larval brain and growth cone motility in the visual system. Here we identify a novel role for Activin signaling in regulating synaptic growth at the larval neuromuscular junction (NMJ). Mutants for Daw, the Activin type I receptor Baboon (Babo), and the signal transducer dSmad2, display reduced NMJ size suggesting that Daw utilizes a canonical Activin signal-transduction pathway in this context. Additionally, loss of Daw/Babo activity affects microtubule stability, axonal transport and distribution of Futsch, the Drosophila microtubule associated protein 1B (MAP1B) homolog. We find that Babo signaling is required postsynaptically in the muscle, in contrast to the well-characterized retrograde BMP/Gbb signal that is required for synaptic growth and function in presynaptic cells. Finally, we show that the Daw/Babo pathway acts upstream of gbb, and is involved in maintenance of muscle gbb expression, suggesting that Activins regulate NMJ growth by modulating BMP activity through transcriptional regulation of ligand expression.

No association between ambient particulate matter exposure during pregnancy and stillbirth risk in the north of England, 1962-1992

OBJECTIVES

Research evidence suggests that exposure to ambient air pollutants can adversely affect the growth and development of the foetus and infant survival. Much less is known regarding the potential for an association between black smoke air pollution and stillbirth risk. This potential association was examined using data from the historical cohort UK Particulate Matter and Perinatal Events Research (PAMPER) study.

METHODS

Using data from paper-based neonatal records from the two major maternity hospitals in Newcastle upon Tyne (UK), a birth record database of all singletons born during 1961-1992 to mothers resident in the city was constructed. Weekly black smoke levels were obtained from routine data recorded at 20 air pollution monitoring stations over the study period. A two-stage statistical modelling strategy was used, incorporating temporally and spatially varying covariates to estimate black smoke exposure during each trimester and for the whole pregnancy period for each individual pregnancy. Conditional logistic regression models, with stratification on year of birth, were used to assess potential associations between black smoke exposures in pregnancy and stillbirth risk.

RESULTS

The PAMPER database consists of 90,537 births, between 1962 and 1992, with complete gestational age and residential address information, of which 812 were stillborn. There was no association between black smoke exposures in any trimester or across whole pregnancy and risk of stillbirth. Adjustment for potential confounders did not alter these results.

CONCLUSIONS

While black smoke in pregnancy is likely to be related to other pregnancy outcomes, our findings do not suggest that black smoke air pollution exposure during pregnancy increases the risk of stillbirth.

Incidence and clinical features of Langerhans cell histiocytosis in the UK and Ireland

OBJECTIVES

There are few published studies on the epidemiology of Langerhans cell histiocytosis (LCH). We undertook a survey to ascertain all newly diagnosed cases aged 0-16 years in the UK and Republic of Ireland.

DESIGN

Three methods of ascertainment were used: the British Paediatric Surveillance Unit (BPSU) system, a survey by Newcastle University, and the Children's Cancer and Leukaemia Group (CCLG) registry. Deaths data were obtained from the UK Office for National Statistics and the Central Statistics Office in Ireland. Clinicians who reported cases were sent a questionnaire to obtain demographic and clinical details.

RESULTS

Over the 2-year period, 94 cases were identified. The age-standardised incidence rate of LCH in children aged 0-14 years was 4.1 per million per year. The sex ratio (M:F) was 1.5:1 and the median age at diagnosis was 5.9 years. Single system disease (predominantly bony involvement) accounted for 73% of cases and 27% had multisystem disease of whom 7% had involvement of "risk organs" (liver, lung, spleen and bone marrow). Three children died, two of whom were diagnosed after death.

CONCLUSIONS

This is the first study of LCH to use an active surveillance method with additional sources of ascertainment. Our incidence is comparable with those in other national reports, although it is likely to be an underestimate as each method may have missed some cases, either diagnosed or undiagnosed.

Dasl(n)e: the challenge of developing a regional database for autism spectrum disorder

The setting up of a database of children with autism spectrum disorder (ASD) in the north east of England is described. Best practice has been followed and included involving parents in planning and implementation at all stages, oversight by a multi-agency group, management by a multidisciplinary steering group, and independent administration of the database. From a potential listing of 986 children with ASD aged 3-12 years, the parents of 511 have so far responded (51.8%), although response rate varies considerably by local authority. Data checking has shown the information to be valid and case ascertainment broadly representative. The uses to which the data are being put and the continuing challenges are outlined.

A follow-up study of children hospitalised with community-acquired pneumonia

OBJECTIVE

To investigate the outcome for children hospitalised with radiologically confirmed community-acquired pneumonia (CAP) DESIGN: Controlled follow-up study.

SETTING

Community based in Newcastle upon Tyne, North Tyneside and Northumberland schools.

PATIENTS

103 cases of radiologically confirmed CAP a median of 5.6 years (range 4.4-7.4) after admission to Newcastle General Hospital, matched for sex and school class to a mean of two controls (n = 248).

INTERVENTIONS

A respiratory questionnaire, clinical examination and spirometry measurements.

MAIN OUTCOME MEASURES

Multiple regression was used to describe associations between explanatory variables, including CAP, and outcome variables: forced expiratory volume in 1 s percent predicted (FEV(1) %), forced vital capacity percent predicted (FVC %), persistent cough, doctor diagnosis of asthma and abnormal chest shape.

RESULTS

Cases were 2.9 times more likely (95% CI 1.45 to 5.71, p = 0.020) than controls to have persistent cough and 5.5 times more likely to have an abnormal chest shape (95% CI 1.65 to 18.28, p = 0.005). Cases of an atopic parent had a 7.0% deficit in FEV(1) % predicted (95% CI -10.5 to -3.2, p<0.001) and a 4.4% deficit in FVC % predicted (95% CI -8.0 to -0.78, p = 0.017), but were not at increased risk of subsequent asthma. Cases of a non-atopic parent were at increased risk of subsequent asthma (OR 4.8, 95% CI 1.43 to 16.34, p = 0.011) but not of deficit in lung function.

CONCLUSIONS

CAP requiring admission to hospital is associated with deficits in lung function and persistent respiratory symptoms. This has implications for follow-up for which recommendations are currently lacking. Parental atopy may be a determinant of outcome.

Special article: chronic granulomatous disease in the United Kingdom and Ireland: a comprehensive national patient-based registry

There are no epidemiological studies from the British Isles of chronic granulomatous disease, characterized by recurrent, life-threatening bacterial and fungal infections and inflammatory sequelae. Patients were enrolled in a national registry and medical records were analysed. Of 94 subjects, 69 had X-linked disease, 16 had autosomal recessive disease and nine were unknown. Prevalence was 7.5/million for 1990-99 and 8.5/million for 1980-89. Suppurative adenitis, abscesses and pneumonia presented commonly. Twenty-three of 30 patients who underwent high resolution computerized tomography had chronic respiratory disease. Inflammatory sequelae included bowel stricture and urogenital tract granulomata. Growth failure was common; 75% of those measured were below the population mean. All patients received prophylactic antibiotics and 93% anti-fungal prophylaxis. Interferon gamma was used to treat infection, but rarely as prophylaxis. Despite prophylaxis, estimated survival was 88% at 10 years but 55% at age 30 years. Morbidity remains significant, severe infectious complications common. Curative treatments including stem cell transplantation should be considered for patients with frequent or serious complications.

Evaluation of the efficacy and safety of a novel formulation of metaflumizone in cats naturally infested with fleas in Europe

The efficacy and safety of a novel spot-on formulation of metaflumizone (ProMeris for Cats, Fort Dodge Animal Health, Overland Park, KS) was assessed in cats naturally infested with fleas in a multiregional, clinical field study. Sixteen veterinary clinics in Germany and eight clinics in France enrolled patients to the study. A total of 173 cats with flea infestation qualified as primary patients and were randomly allocated to one of the two treatments in a ratio of approximately 2:1 for metaflumizone (minimum dosage of 40mg/kg) or fipronil (at the recommended label rate). Clinical examinations and baseline parasite counts were performed on Day 0 prior to treatment. Flea counts and safety evaluations were repeated at approximately 2-week intervals for 8 weeks. Both treatments resulted in consistent reductions (>84%) in flea numbers throughout the study, but metaflumizone resulted in numerically higher reductions on most count days. Within groups the flea reduction was highly significant (p<0.0001) compared to baseline at all observation periods. The efficacy of metaflumizone against fleas compared to baseline was 91.0%, 89.4%, 90.8% and 90.7% at Day 14, 28, 42 and 56, respectively. The corresponding efficacies for fipronil were 91.7%, 86.9%, 84.6% and 87.7%. Metaflumizone was highly effective in controlling existing infestations of fleas on cats and was effective against reinfestation for at least 56 days. Metaflumizone showed a good tolerance profile in cats.

Epidemiology of community-acquired pneumonia in children seen in hospital

There is little UK data on hospital admission rates for childhood pneumonia, lobar pneumonia, severity or risk factors. From 13 hospitals serving the catchment population, demographic and clinical details were prospectively collected between 2001 and 2002 for children aged 0-15 years, seen by a paediatrician with community-acquired pneumonia (CAP) and consistent chest X-ray changes. From 750 children assessed in hospital, incidence of CAP was 14.4 (95% CI 13.4-15.4)/10,000 children per year and 33.8 (95% CI 31.1-36.7) for <5-year-olds; with an incidence for admission to hospital of 12.2 (95% CI 11.3-13.2) and 28.7 (95% CI 26.2-31.4) respectively. Where ascertainment was confirmed, incidence of CAP assessed in hospital was 16.1 (95% CI 14.9-17.3) and 41.0 (95% CI 37.7-44.5) in the 0-4 years age group, whilst incidence for hospital admission was 13.5 (95% CI 12.4-14.6) and 32 (95% CI 29.1-35.1) respectively. In the <5 years age group incidence of lobar pneumonia was 5.6 (95% CI 4.5-6.8)/10,000 per year and severe disease 19.4 (95% CI 17.4-21.7)/10,000 per year. Risk of severe CAP was significantly increased for those aged <5 years (OR 1.50, 95% CI 1.07-2.11) and with prematurity, OR 4.02 (95% CI 1.16-13.85). It also varied significantly by county of residence. This is a unique insight into the burden of hospital assessments and admissions caused by childhood pneumonia in the United Kingdom and will help inform future preventative strategies.

Evidence of an environmental contribution to the aetiology of cryptorchidism and hypospadias?

OBJECTIVES

Evidence suggests that there is geographical variation in the birth prevalence of both cryptorchidism and hypospadias. The aim was to determine if there is evidence of spatial heterogeneity in the prevalence of these conditions and to test the hypothesis that environmental factors may contribute to aetiology.

METHODS

A population-based dataset of cryptorchidism and hypospadias cases was constructed from the hospital episodes statistics that covered the Northern Region of England and assigned to a small area based on the residential address at time of admission. Expected numbers of cases for each small area were computed. The ratio of observed to expected cases was determined for each small area and analysed with respect to both geographical heterogeneity and small area level socio-economic deprivation. The Potthoff-Whittinghill method was used to determine if there was localized spatial clustering of cases.

RESULTS

There was statistically significant spatial clustering for cases of both cryptorchidism [estimated Extra-Poisson Variation (EPV) = 0.14; 95% CI, 0.03-0.25] and hypospadias (EPV = 0.17; 95% CI, 0.05-0.28). In addition, increased prevalence was associated with lower levels of deprivation for hypospadias (P = 0.06), but there was no such relationship for cryptorchidism (P = 0.61).

CONCLUSIONS

The finding of localized spatial heterogeneity in the prevalence of cryptorchidism and hypospadias is consistent with the involvement of a spatially varying environmental risk factor. The apparent social patterning of hypospadias is likely to reflect an association with lifestyle and other factors which underpin social variation in health. However, there also remains a possibility that these findings may be due to variability in ascertainment of cases.

Birth prevalence of cryptorchidism and hypospadias in northern England, 1993-2000

AIM

There is much debate as to whether the prevalence rates of cryptorchidism and hypospadias are increasing. To address this issue we investigated the birth prevalence of cryptorchidism and hypospadias in the northern region of England during the period 1993-2000.

METHODS

Cases of cryptorchidism and hypospadias were identified from northern region hospital episodes statistics (HES). Trends in birth prevalence, based on the number of male live births, were assessed using linear regression.

RESULTS

Prevalence was 7.6 per 1000 male live births for cryptorchidism and 3.1 per 1000 male live births for hypospadias. The orchidopexy rates for 0-4 year olds and 5-14 year olds were 1.8 and 0.8 per 1000 male population, respectively. The rates for hypospadias repair for 0-4 year olds and 5-14 year olds were 0.6 and 0.1 per 1000 male population, respectively. There was a statistically significant decreasing temporal trend for the corrective procedure in cryptorchidism of 0.1 per 1000 male population aged under 5 years per annum (95% confidence interval: -0.01 to -0.05, p<0.001), but no temporal change for the corrective procedure in hypospadias (p = 0.60).

CONCLUSION

HES data were of high quality for the study period. There was no significant change in the prevalence of surgically corrected hypospadias. However, there was an apparent decline in the prevalence of surgically corrected cryptorchidism that may reflect a decrease in the prevalence of the condition or may be due to a decrease in the rate of surgical intervention.