GABRD encoding a protein for extra- or peri-synaptic GABAA receptors is a susceptibility locus for generalized epilepsies

A major challenge in understanding complex idiopathic generalized epilepsies has been the characterization of their underlying molecular genetic basis. Here, we report that genetic variation within the GABRD gene, which encodes the GABAA receptor delta subunit, affects GABA current amplitude consistent with a model of polygenic susceptibility to epilepsy in humans. We have found a GABRD Glu177Ala variant which is heterozygously associated with generalized epilepsy with febrile seizures plus. We also report an Arg220His allele in GABRD which is present in the general population. Compared with wild-type receptors, alpha1beta2Sdelta GABAA receptors containing delta Glu177Ala or Arg220His have decreased GABAA receptor current amplitudes. As GABAA receptors mediate neuronal inhibition, the reduced receptor current associated with both variants is likely to be associated with increased neuronal excitability. Since delta subunit-containing receptors localize to extra- or peri-synaptic membranes and are thought to be involved in tonic inhibition, our results suggest that alteration of this process may contribute to the common generalized epilepsies.     

Immunological mechanisms in the maintenance of pregnancy

Mmammalian pregnancy involves prolonged, intimate interactions between genetically dissimilar organisms. This dissimilarity evokes an immunological response in the gravida which promotes placental implantation and fetal viability. The nature of the immunological reactions, the factors moderating these responses and the signficance of abnormalities in the responses are discussed.     

Prevention of spinal cord injury: an elementary education approach.

Spinal cord injury (SCI) results in permanent paralysis and most often happens to teenagers and young adults. High risk behaviors are most often the cause; therefore these injuries are often preventable. In response to a gap in existing prevention programs, an elementary age SCI prevention program was developed, designed for implementation by teachers. Evaluation was carried out via a quasi-experimental pre-post comparison group design. Experimental students demonstrated significantly improved knowledge of SCI and its prevention. Similar changes in self-reported safety belt use were not noted. Development of the curriculum, related grant activities, and plans for national dissemination are described.     

Solitary magnocellular neurons in the homozygous Brattleboro rat have vasopressin and glycopeptide immunoreactivity

A small but distinctive population (about 1 in 600) of magnocellular neurosecretory neurons in homozygous Brattleboro rats are immunoreactive for vasopressin, and a similar number for the carboxy-terminal glycopeptide of the vasopressin prohormone. These solitary cells are found in all animals and in all parts of the magnocellular system, but not in the suprachiasmatic or other hypothalamic nuclei. The majority of the solitary cells do not differ morphologically from the remainder of the magnocellular neurons. The immunoreactivity is markedly denser in the Nissl bodies than in the Golgi region. Serial sections show that the vasopressin and glycopeptide immunoreactive material is co-localized in the same cells, and that these cells are not immunoreactive for oxytocin. A published sequence for the Brattleboro vasopression gene mutation indicates a base-deletion upstream from the glycopeptide-encoding portion, and implies a frameshift that would cause translation of incorrect protein continuing into the poly-A tail of the mRNA. Although this could apply to the majority of the Brattleboro presumptive vasopressin neurons, the co-localization in our solitary cells of material immunoreactive with antibodies to both the amino- and carboxy-terminals of the vasopressin prohormone suggest that in these cases an additional mechanism may be operating.     

Diversity of enteric viruses detected in patients with gastroenteritis in a tertiary referral paediatric hospital

The genetic diversity of enteric viruses co-circulating in a cohort of patients with viral gastroenteritis in a large tertiary paediatric hospital in London, UK, was determined. Multiple strains of noroviruses (NV), sapoviruses (SV) and astroviruses (HAsV) were detected in these patients, indicating the likelihood of multiple introductions from different sources, possible sub-clinical infections and simultaneous infection with different viruses in immunocompromised and other patients. Routine screening of immunocompromised patients and infection control procedures are important to prevent nosocomial infection.     

Effect of the 21-aminosteroid,U-74389F,on hyperoxic lung injury in rats

Hyperoxia (>95% oxygen) in rats caused an increase in lung weight and an accumulation of fluid in the thorax. The mean lung wet weight of air-breathing controls at 60 h was 1.2±0.01 g, and that of vehicle-treated, oxygen-exposed animals was 2.45±0.05 g. Treatment with the 21-aminosteroid U-74389F, 3, 10, and 30 mg/kg twice daily throughout oxygen exposure, produced 8, 42, and 18% inhibition of the oxygen-induced increase in lung weight, respectively. However, U-74389F did not inhibit the hyperoxia-induced accumulation of neutrophils in bronchoalveolar lavage fluid.

No pleural fluid could be aspirated from the thorax of air-breathing controls. The volume of pleural fluid in oxygen-exposed, vehicle-treated animals and animals treated with 3, 10, and 30 mg/kg U-74389F b.i.d. was 6.5±0.9, 2.6±0.6, 0.8±0.3, and 1.3±0.5 ml, respectively.

U-74389F or its biologs are of potential value for the treatment of lung diseases in which oxidant damage has been implicated.

     

Molecular analysis of de novo germline mutations in the von Hippel-Lindau disease gene

VHL disease is a dominantly inherited familial cancer syndromewith variable expression and age-dependent penetrance. The diagnosisof isolated cases is often delayed compared with familial cases,and estimates of the new mutation rate have varied more than20-fold. To investigate the frequency and origin of de novoVHL gene mutations we have analysed: (i) families with identicalmutations to determine if there is a common haplotype, and (ii)apparent new mutation cases to determine whether the clinicaldiagnosis of such cases is reliable and to define the parentalorigin of de novo VHL gene mutations. Haplotyping of 12 VHLmutations occurring in two or more families (total 42 kindreds)revealed that for most mutations there was no evidence of afounder effect. A marked bias for a paternal origin of new mutationshas been reported in other familial cancer syndromes such asneurofibromatosis type 1 (NF1), multiple endocrine neoplasia(MEN) 2B and bilateral retinoblastoma, but it is unclear whetherthis bias results from a greater susceptibility for mutagenesisduring male gametogenesis because of the larger number of celldivisions compared with that in oogenesis, or from genomic imprintingeffects. Analysis of 13 de novo VHL mutations in which the parentof origin could be established, showed no evidence for a biasfor a paternal origin (seven paternal, six maternal), and differedsignificantly from that reported in NF1, MEN2B and bilateralretinoblastoma. This result demonstrates that an increased susceptibilityto paternal allele mutation is not a universal finding in autosomalgenetic diseases and that the origin of new mutations may beinfluenced by both genomic imprinting effects and the increasednumber of cell divisions in spermatogenesis compared with oogenesis.     

Is personal continuity of care compatible with free choice of doctor? Patients' views on seeing the same doctor.

While much has been written about the benefits of personal continuity of care there has been little research about the views of patients. In this cross sectional study 111 patients from three group practices (one of which ran a personal list system) were interviewed at home within a week of consulting a general practitioner. Patients were selected randomly from a systematic series of consulting sessions and a semi-structured interview was administered. Patients receiving more personal continuity of care were likely to be older, to have booked their most recent appointment further in advance, to desire personal continuity of care, to have an external health locus of control and to have a lower extroversion score. In the practice with a personal list, patients had a high level of continuity of care, were satisfied and showed little interest in having a choice of doctor. In the combined list practices patients valued their choice of doctor but often could not exercise it enough and they were more critical. They made more suggestions for change than those in the practice with a personal list system, mostly about receptionists and appointments. It is concluded that most patients like to see the same doctor, but they may not be willing to wait two days for this if there is a quicker option. It may be difficult to deliver both personal continuity of care and choice in group practice.     

Intranasal and inhaled fluticasone propionate for pollen-induced rhinitis and asthma

BACKGROUND: Studies suggest that nasal treatment might influence lower airway symptoms and function in patients with comorbid rhinitis and asthma. We investigated the effect of intranasal, inhaled corticosteroid or the combination of both in patients with both pollen-induced rhinitis and asthma. METHODS: A total of 262 patients were randomized to 6 weeks' treatment with intranasal fluticasone propionate (INFP) 200 microg o.d., inhaled fluticasone propionate (IHFP) 250 microg b.i.d., their combination, or intranasal or inhaled placebo, in a multicentre, double-blind, parallel-group study. Treatment was started 2 weeks prior to the pollen season and patients recorded their nasal and bronchial symptoms twice daily. Before and after 4 and 6 weeks' treatment, the patients were assessed for lung function, methacholine responsiveness, and induced sputum cell counts. RESULTS: Intranasal fluticasone propionate significantly increased the percentages of patients reporting no nasal blockage, sneezing, or rhinorrhoea during the pollen season, compared with IHFP or intranasal or inhaled placebo. In contrast, only IHFP significantly improved morning peak-flow, forced expiratory volume in 1 second (FEV1) and methacholine PD20, and the seasonal increase in the sputum eosinophils and methacholine responsiveness. CONCLUSIONS: In patients with pollen-induced rhinitis and asthma, the combination of intranasal and IHFP is needed to control the seasonal increase in nasal and asthmatic symptoms.     

Best practice in primary care pathology: review 1

This first best practice review examines four series of common primary care questions in laboratory medicine, namely: (i) measurement and monitoring of cholesterol and of liver and muscle enzymes in patients in the context of lipid lowering drugs, (ii) diagnosis and monitoring of vitamin B12/folate deficiency, (iii) investigation and monitoring of paraprotein bands in blood, and (iv) management of Helicobacter pylori infection. The review is presented in a question-answer format, referenced for each question series. The recommendations represent a précis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents, and evidence based medicine reviews, supplemented by MEDLINE EMBASE searches to identify relevant primary research documents. They are not standards but form a guide to be set in the clinical context. Most are consensus rather than evidence based. They will be updated periodically to take account of new information.