Molecular cloning and characterisation of a novel GABAB-related G-protein coupled receptor

Using a homology-based bioinformatics approach we have analysed human genomic sequence and identified the human and rodent orthologues of a novel putative seven transmembrane G protein coupled receptor, termed GABA(BL). The amino acid sequence homology of these cDNAs compared to GABA(B1) and GABA(B2) led us to postulate that GABA(BL) was a putative novel GABA(B) receptor subunit. The C-terminal sequence of GABA(BL) contained a putative coiled-coil domain, di-leucine and several RXR(R) ER retention motifs, all of which have been shown to be critical in GABA(B) receptor subunit function. In addition, the distribution of GABA(BL) in the central nervous system was reminiscent of that of the other known GABA(B) subunits. However, we were unable to detect receptor function in response to any GABA(B) ligands when GABA(BL) was expressed in isolation or in the presence of either GABA(B1) or GABA(B2). Therefore, if GABA(BL) is indeed a GABA(B) receptor subunit, its partner is a potentially novel receptor subunit or chaperone protein which has yet to be identified.

Search for supernova relic neutrinos at Super-Kamiokande

A search for the relic neutrinos from all past core-collapse supernovae was conducted using 1496 days of data from the Super-Kamiokande detector. This analysis looked for electron-type antineutrinos that had produced a positron with an energy greater than 18 MeV. In the absence of a signal, 90% C.L. upper limits on the total flux were set for several theoretical models; these limits ranged from 20 to 130 macro nu(e) cm(-2) s(-1). Additionally, an upper bound of 1.2 macro nu(e) cm(-2) s(-1) was set for the supernova relic neutrino flux in the energy region E(nu)>19.3 MeV.

Survey of autologous blood transfusion activity in England (2001)

Better Blood Transfusion' (Department of Health (1998) HSC 1998/224) stressed the need for National Health Service Trusts to explore the feasibility of autologous blood transfusions and raise patient awareness of these techniques. The development of an appropriate strategy to promote autologous transfusion requires an understanding of current use, along with constraints to increasing practice. Past surveys have shown unchanging attitudes to autologous transfusion (Torrella et al. (2001) Transfusion Medicine, 11, 15-19), but detailed information regarding the extent of autologous transfusion in England and North Wales was not available. This survey, carried out in 2001, considered autologous transfusion under four headings: predeposit autologous donation, acute normovolaemic haemodilution, intra-operative cell salvage and postoperative cell salvage. Questionnaires were returned from 265/310 (85.4%) hospitals served by the National Blood Service. Sixty per cent of respondents performed at least one autologous technique, although practice was limited to a few clinicians within each hospital. Predeposit donation was the most widespread technique but involved very few patients. Intra- and postoperative cell salvage techniques were practised in fewer hospitals but on many more patients. The main constraints to increasing use of autologous techniques were perceived to be logistical, but removal of constraints may only result in small increases in individual practice. More clinicians need to be encouraged to utilize appropriate, evidence-based autologous techniques.

Effects of rheumatoid arthritis on sexual activity and relationships

OBJECTIVES

The primary aim of this research was to assess patients' perceptions of the effects of rheumatoid arthritis (RA) on their sexual relationship and sexual activity, the causes of any difficulties and who they would turn to for help.

METHODS

A self-report questionnaire was distributed to 74 patients attending a regional rheumatology clinic and returned by prepaid post. Fifty-nine questionnaires were returned (response rate 80%) and 57 of them were usable.

RESULTS

Thirty-five per cent of the cohort thought that their disease strained their relationship with their partner, and reasons for this included curtailment of daily and social activities, changes in the balance of the relationship, emotional changes and changed financial circumstances. Over half (56%) of the patients found that their arthritis placed limitations on sexual intercourse and the principal reasons cited were fatigue and pain. Sexual ability was important to 58% of the sample and ageing had a negative impact on its importance (P<0.005). Poor communication was a major problem, patients being reluctant to approach health professionals and vice versa. The topic of sexual relationships was broached with patients attending one nurse practitioner's clinic, but only one other patient had ever been offered any discussion. Thirty-nine per cent of the cohort would consider talking to someone if they had a problem and the nurse and the doctor were the professionals most often chosen.

CONCLUSION

RA impacts on the sexual lives of a large minority of patients and this is a problem that patients and health professionals are reluctant to discuss face to face. However, patients do appear to be willing to complete questionnaires and this may be an acceptable format for assessment. Further training and support is needed by nurses and other health professionals in this sadly neglected area.

Yersinia pestis and plague

Yersinia pestis is the aetiological agent of plague, a disease of humans that has potentially devastating consequences. Evidence indicates that Y. pestis evolved from Yersinia pseudotuberculosis, an enteric pathogen that normally causes a relatively mild disease. Although Y. pestis is considered to be an obligate pathogen, the lifestyle of this organism is surprisingly complex. The bacteria are normally transmitted to humans from a flea vector, and Y. pestis has a number of mechanisms which allow survival in the flea. Initially, the bacteria have an intracellular lifestyle in the mammalian host, surviving in macrophages. Later, the bacteria adopt an extracellular lifestyle. These different interactions with different host cell types are regulated by a number of systems, which are not well characterized. The availability of the genome sequence for this pathogen should now allow a systematic dissection of these regulatory systems.

Indications of neutrino oscillation in a 250 km long-baseline experiment

The K2K experiment observes indications of neutrino oscillation: a reduction of nu(mu) flux together with a distortion of the energy spectrum. Fifty-six beam neutrino events are observed in Super-Kamiokande (SK), 250 km from the neutrino production point, with an expectation of 80.1(+6.2)(-5.4). Twenty-nine one ring mu-like events are used to reconstruct the neutrino energy spectrum, which is better matched to the expected spectrum with neutrino oscillation than without. The probability that the observed flux at SK is explained by statistical fluctuation without neutrino oscillation is less than 1%.

The accumulation of potentially toxic elements in edible body tissues of lambs grazing after a single application of sewage sludge

The application of sewage sludge to grassland can lead to the accumulation of potentially toxic elements (PTEs) at the soil surface that may be ingested, together with soil and herbage, by grazing ruminants. To investigate the extent to which the method of application of sludge to grassland might influence the accumulation of PTEs in body tissues of grazing sheep, two experiments were undertaken using grassland overlying two contrasting types of soil. At both sites, plots were either untreated or given liquid digested sludge in a single application in either autumn or spring by surface spreading or by injection. Weaned lambs were grazed on the experimental sites for 149 days (Experiment 1) or 160 days (Experiment 2). Muscle, kidney and liver tissues were assayed for concentrations of PTEs at each slaughter date. Applications of sludge were reflected in elevated concentrations of Pb and Cu in soil in Experiment 1 only (P < 0.05). Total loadings of PTEs for the treated grasslands did not exceed UK statutory limits to annual additions to soil. No significant differences were observed in the concentrations of PTEs in herbage between untreated and treated sites, with the exception of the concentration of Cu in herbage after surface application in the spring (Experiment 2). At the end of Experiment 1 the concentration of Cd tended to be higher in kidney tissues of lambs grazed on the pastures amended with sludge in the autumn compared to lambs grazed on untreated pastures. No other treatment effects were evident. Concentrations of PTEs in edible tissues of lambs grazed on grassland given a single dose of sludge were generally low and unlikely to pose a significant risk to the food chain. However, reduced food intake was observed in lambs grazed on grassland which had received sludge recently, indicating that the 21-day UK statutory no-grazing period should be reviewed in relation to grassland given sewage sludge in the spring.

The development and evaluation of a drug information leaflet for patients with rheumatoid arthritis

OBJECTIVES

To develop and assess the effectiveness of a drug information leaflet (DIL) for D-penicillamine (DPA) and determine whether additional verbal information provides enhanced benefit.

METHODS

Three preliminary studies were undertaken: a reading age study; the development of a DIL for DPA; and a DPA knowledge questionnaire. The primary study assessed the effect of the DIL on the knowledge of 30 patients at weeks 0 and 24 after commencing DPA. A follow-up study of 100 patients randomly assigned to receive the DIL alone (control group) or with additional verbal backup (experimental group) determined the effects of additional verbal information by comparison of DPA knowledge questionnaire scores at weeks 0 and 24.

RESULTS

The reading study showed that 12% of the sample had difficulty reading and so the DPA DIL was designed to be easy to read using the Flesch Reading Index. An assessment of knowledge of DPA prior to reading the DIL resulted in scores ranging from 0 to 13 with a median of 2 (maximum possible 14). By week 24 the median score was 10 (range 6-14), which was significant at P < 0.0001. The assessment of additional verbal backup showed that both the control group and the experimental group knew little about DPA on study entry, with a median score 2 in each group. On study exit, both groups knew significantly more (P < 0.001) about the drug; the control group scored 9 and the experimental group 11 (not significantly different; P=0.109).

CONCLUSIONS

A large minority of patients have poor reading skills, but when a DIL is designed to be easy to read patients gain significant amounts of knowledge from it. Providing additional verbal explanations did bring about increases in knowledge but these were not significant.

Two cases of immune haemolytic anaemia, associated with anti-piperacillin, detected by the 'immune complex' method

BACKGROUND AND OBJECTIVES

Sera containing antibodies to penicillin and penicillin-related drugs are typically thought to react with drug-coated red blood cells (RBCs) (drug adsorption method), but not when the sera are added to drug and RBCs in the same tube ('immune complex' method). Two cases of immune haemolytic anaemia caused by anti-piperacillin have been previously described. Serological details were given in only one patient. In that subject, the antibody was immunoglobulin (Ig)M + IgG and reacted by both the drug adsorption and 'immune complex' methods.

MATERIALS AND METHODS

Two patients with cystic fibrosis developed positive direct antiglobulin tests (DATs) and haemolytic anaemia after 11-12 days of piperacillin therapy. Serological studies were performed with piperacillin, Zosyn (piperacillin + tazobactam) and penicillin by using the drug adsorption and 'immune complex' methods.

RESULTS

The first patient's serum contained an IgG, complement-activating anti-piperacillin that reacted by the 'immune complex' method only. The second patient's IgM + IgG, complement-activating anti-piperacillin reacted by the 'immune complex' method and agglutinated piperacillin-treated RBCs. An eluate from the patient's RBCs reacted weakly with all RBCs tested without the presence of drug. This patient had evidence of intravascular haemolysis and died.

CONCLUSIONS

We describe the third and fourth examples of immune haemolytic anaemia caused by anti-piperacillin; one was associated with fatal haemolytic anaemia. As piperacillin is commonly used in the treatment of cystic fibrosis, anti-piperacillin should be considered whenever patients with cystic fibrosis develop haemolytic anaemia and/or positive DATs.

Genome sequencing of a 239-kb region of rice chromosome 10L reveals a high frequency of gene duplication and a large chloroplast DNA insertion

In this study we describe a 239-kb region on the long arm of rice chromosome 10 that contains a high density (71%) of locally duplicated genes, including 24 copies of a glutathione S-transferase gene. Intriguingly, embedded within this cluster is a large insertion (approximately 33 kb) of rice (Oryza sativa) chloroplast DNA that is derived from two separate regions of the chloroplast genome. We used DNA fiber-based fluorescence in situ hybridization (fiber-FISH) analyses of O. sativa spp. japonica nuclei to confirm that the insertion of organellar DNA was not a cloning artifact. The sequence of the chloroplast insertion is nearly identical (99.7% identity) to the corresponding regions in the published rice chloroplast genome sequence, suggesting that the transfer event occurred recently. PCR amplification and sequence analysis in two subspecies of rice, O. sativa spp. japonica and spp. indica, indicates that the transfer event predated the divergence of these two subspecies. The chloroplast insertion is flanked by a 2.1-kb perfect direct repeat that is unique to this location in the rice genome.

Anti-V antigen antibody protects macrophages from Yersinia pestis -induced cell death and promotes phagocytosis

The pathogenic Yersinia spp. harbor a common plasmid (pYV) essential for virulence. The plasmid encodes a type III secretion system that functions to translocate Yersinia outer proteins (Yops) into the host cytosol. Within the host cell, the Yops act to inhibit phagocytosis and induce apoptosis. One of the plasmid-encoded proteins, virulence antigen (V), is a major protective immunogen that is involved in Yop translocation. Yersinia pestis, like the enteric Yersinia spp., was both resistant to phagocytosis by and cytotoxic for J774.A1, a murine macrophage cell line. Both of these activities were dependent on culture of the bacteria at 37 degrees C for 1.5-2 h before infection. However, extending the preculture period at 37 degrees C to 24 h, which induced formation of a capsule, completely blocked cytotoxicity. Treating the bacteria with either rabbit polyclonal anti-V antibodies (R anti-V) or monoclonal antibody (MAb) 7.3, antibodies specific for V and protective against plague in vivo, protected J774.A1 cells from Y. pestis -induced cell death and also reversed the inhibition of phagocytosis. Whereas protection against cell cytotoxicity was afforded by the F(ab')(2) portion of R anti-V, the ability of anti-V to induce uptake of Y. pestis appeared to be dependent on the Fc portion of the Ab. The protective epitope(s) recognized by R anti-V was contained in the central region of Y. pestis V (aa 135-275) and were partially cross reactive with Y. pseudotuberculosis and Y. enterocolitica serotype 08 V antigens.

Preperitoneal approach to parastomal hernia with coexistent large incisional hernia

OBJECTIVE: To assess the outcome of preperitoneal mesh repair of complex incisional herniae incorporating a stoma and large parastomal hernia. METHODS: From 1994 to 1998, symptomatic patients who had repair of combined incisional hernia and parastomal hernia were reviewed. Body mass index, co-morbidity, length of hospital stay, patient satisfaction and outcomes were recorded. RESULTS: Ten patients (seven females and three males), mean age 62 (range 48-80) years underwent primary repair. All had significant comorbidities (ASA grade 3) and mean body mass index was 31.1 (range 20-49). Median hospital stay was 15 (range 8-150) days. Complications were of varying clinical significance (seroma, superficial infection, major respiratory tract infection and stomal necrosis). There were no recurrences after a mean follow up of 54 (range 22-69) months. CONCLUSION: The combination of a parastomal hernia and generalised wound dehiscence is an uncommon but difficult problem. The application of the principles of low-tension mesh repair can provide a satisfactory outcome and low recurrence rate. This must be tempered by recognition of the potential for significant major postoperative complication.

Ammonia emission, deposition and impact assessment at the field scale: a case study of sub-grid spatial variability

A local ammonia (NH3) inventory for a 5x5 km area in central England was developed, to investigate the variability of emissions, deposition and impacts of NH3 at a field scale, as well as to assess the validity of the UK 5-km grid inventory. Input data were available for the study area for 1993 and 1996 on a field by field basis, allowing NH3 emissions to be calculated for each individual field, separately for livestock grazing, livestock housing and manure storage, landspreading of manures and fertiliser N application to crops and grassland. An existing atmospheric transport model was modified and applied to model air concentrations and deposition of NH3 at a fine spatial resolution (50 m grid). From the mapped deposition estimates and land cover information, critical loads and exceedances were derived. to study the implications of local variability for regional NH3 impacts assessments. The results show that the most extreme local variability in NH3 emissions, deposition and impacts is linked to housing and storage losses. However, landspreading of manures and intensive cattle grazing are other important area sources, which vary substantially in the landscape. Overall, the range of predicted emissions from agricultural land within the study area is 0-2000 kg N ha(-1) year(-1) in 1993 and 0-8000 kg N ha(-1) year(-1) in 1996, respectively, with the peak at a poultry farm located in the study area. On average, the estimated field level NH3 emissions over the study area closely match the emission for the equivalent 5-km grid square in the national inventory for 1996. Deposition and expected impacts are highly spatially variable, with the edges of woodland and small "islands" of semi-natural vegetation in intensive agricultural areas being most at risk from enhanced deposition. Conversely the centres of larger nature reserves receive less deposition than average. As a consequence of this local variability it is concluded that national assessments at the 5 km grid level underestimate the occurrence of critical loads exceedances due to NH3 in agricultural landscapes.

Can we predict perceived risk?

This paper examines the possibility that we may be able to use subjective measures of perceived risk in order to assess the relative safety of different shift systems. A large-scale survey of safety-critical engineers included three items relating to risk on each shift, namely alertness, likelihood of making a mistake and confidence in driving home after it. These three measures were found to load on a separate factor for each shift. Hierarchical regression analyses indicated that perceived night shift risk could be predicted on the basis of circadian type, the extent to which the engineers could control their work schedule, and a number of features of the scheduled shift system. In most cases the relationships observed were reasonably consistent with established trends in either performance capability or accident and injury frequency. However, there were exceptions to this indicating that results based on measures of perceived risk should be interpreted with the utmost caution.

Pathophysiology of apolipoprotein E deficiency in mice: relevance to apo E-related disorders in humans

Apolipoprotein E (apo E) deficiency (or its abnormalities in humans) is associated with a series of pathological conditions including dyslipidemia, atherosclerosis, Alzheimer's disease, and shorter life span. The purpose of this study was to characterize these conditions in apo E-deficient C57BL/6J mice and relate them to human disorders. Deletion of apo E gene in mice is associated with changes in lipoprotein metabolism [plasma total cholesterol (TC) (>+400%), HDL cholesterol (-80%), HDL/TC, and HDL/LDL ratios (-93% and -96%, respectively), esterification rate in apo B-depleted plasma (+100%), plasma triglyceride (+200%), hepatic HMG-CoA reductase activity (-50%), hepatic cholesterol content (+30%)], decreased plasma homocyst(e)ine and glucose levels, and severe atherosclerosis and cutaneous xanthomatosis. Hepatic and lipoprotein lipase activities, hepatic LDL receptor function, and organ antioxidant capacity remain unchanged. Several histological/immunohistological stainings failed to detect potential markers for neurodegenerative disease in the brain of 37-wk-old male apo E-KO mice. Apo E-KO mice may have normal growth and development, but advanced atherosclerosis and xanthomatosis may indirectly reduce their life span. Apo E plays a crucial role in regulation of lipid metabolism and atherogenesis without affecting lipase activities, endogenous antioxidant capacity, or appearance of neurodegenerative markers in 37-wk-old male mice.

Constitutive tyrosine phosphorylation of the GABA(A) receptor gamma 2 subunit in rat brain

GABA(A) receptors are the major sites of fast synaptic inhibition in the brain, where they are predominantly composed of alpha, beta and gamma2 subunits. A role for direct tyrosine phosphorylation of residues 365 and 367 (Y365/367) within the intracellular domain of the gamma2 subunit has been suggested to be important in modulating GABA(A) receptor function, based on the study of recombinant receptors. To address the relevance of these observations for neuronal GABA(A) receptors we have studied the phosphorylation of the gamma2 subunit in the brain. In adult rat brain the gamma2 subunit is phosphorylated on tyrosine residues, including Y365/367 as defined using a phosphospecific antisera. In cultured cortical neurones, phosphorylation of Y365/367 is highly regulated and was only evident upon inhibition of tyrosine phosphatases. We also establish that the tyrosine kinase Src is capable of specifically interacting with the intracellular domains of receptor beta and gamma2 subunits. This may specifically localise tyrosine kinase activity to GABA(A) receptors, facilitating rapid receptor tyrosine phosphorylation upon kinase activation. Together our results suggests that tyrosine phosphorylation of the gamma2 subunit, possibly by closely associated Src, may be a dynamic mechanism for regulating GABA(A) receptor function in the brain.

Fabry disease: 20 novel GLA mutations in 35 families

Thirty two mutations have been found in 35 unrelated patients of European origin with Fabry disease, including 8 females. Twenty of the mutations are novel and comprise of 13 missense: H46Y, W47G, R49P, C94S, F113S, G258R, P259R, Q279H, Q280H, R363H, A377D, P409A, P409T; 1 nonsense: L294X; 5 small deletions: 154delT, 520delT, 909-918del10, 1152-1153delCA, 1235-1236delCT and 1 splice site mutation: IVS5+2t-->c. The remaining 12 mutations have all been reported previously. All patients with deletions had the classic form of the disease but it was not possible to predict the phenotype from the missense mutations.

A guide for diagnosis of patients with arterial and venous thrombosis

Inasmuch as coagulation laboratories are involved in providing a diagnosis for underlying causes of venous and arterial thrombosis, we present a comprehensive review of the biological properties and functions of the components of the hemostatic system as they relate to the diagnosis of arterial and venous thrombosis. Moreover, as coagulation laboratories are necessary to evaluate the success of initial treatment modalities and to provide guidance for supplemental therapeutic intervention, we include information on antiplatelet and antithrombotic therapy. Included in clinical coagulation testing are assays that evaluate the potential of blood to form clots and tests for platelet numbers and platelet functions. Clot-based assays directly detect the biological activity of procoagulant factors and fibrinogen; chromogenic substrate assays evaluate proteolytic activities of clotting as well as fibrinolysis enzymes; and specific antibodies measure the concentrations of coagulation and fibrinolysis enzymes in plasma. Genetic testing is rapidly becoming incorporated into the clinical routine. The prothrombin time (PT), activated partial prothrombin time (APTT), and thrombin time (TT) are screening assays that measure the clotting times of recalcified whole blood or platelet-poor plasma. In addition to their function as screening assays, PT, APTT, and TT are the backbone of all the specialized clot-based assays for factor activities and for the indirect measurement of inhibitory antithrombin and protein C activities. Molecular markers related to hemostasis and fibrinolysis consist of proteins or peptides that indicate an ongoing physiological or abnormal process related to clot formation, thrombosis, vascular damage, or drug effect. Molecular markers are currently identified by means of specific antibodies prepared against them. The list of hemostatic molecular markers is rapidly growing. Most of the assays developed for molecular marker measurement, with the notable exception of the d-dimer assay, are typically used in clinical research.