The Genome sequence of the SARS-associated coronavirus

We sequenced the 29,751-base genome of the severe acute respiratory syndrome (SARS)-associated coronavirus known as the Tor2 isolate. The genome sequence reveals that this coronavirus is only moderately related to other known coronaviruses, including two human coronaviruses, HCoV-OC43 and HCoV-229E. Phylogenetic analysis of the predicted viral proteins indicates that the virus does not closely resemble any of the three previously known groups of coronaviruses. The genome sequence will aid in the diagnosis of SARS virus infection in humans and potential animal hosts (using polymerase chain reaction and immunological tests), in the development of antivirals (including neutralizing antibodies), and in the identification of putative epitopes for vaccine development.

Apoptotic cells protect mice from autoimmune inflammation by the induction of regulatory B cells

The maintenance of immune tolerance to apoptotic cells (AC) within an inflammatory milieu is vital to prevent autoimmunity. To investigate this, we administered syngeneic AC i.v. into mice carrying a cohort of ovalbumin (OVA)-specific transgenic T cells (DO11.10) along with OVA peptide and complete Freund's adjuvant, observing a dramatic increase in OVA-specific IL-10 secretion. Activated splenic B cells responded directly to AC, increasing secretion of IL-10, and this programming by AC was key to inducing T cell-derived IL-10. We went on to ask whether AC are able to modulate the course of autoimmune-mediated, chronic inflammation. AC given up to 1 month before the clinical onset of collagen-induced arthritis protected mice from severe joint inflammation and bone destruction. Antigen-specific CD4(+) T cells again secreted significantly more IL-10, associated with a reduced titer of pathogenic anti-collagen II antibodies. Inhibition of IL-10 in vivo reversed the beneficial effects of AC. Passive transfer of B cells from AC-treated mice provided significant protection from arthritis. These data demonstrate that AC exert a profound influence on an adaptive immune response through the generation of CD19(+) regulatory B cells, which in turn are able to influence the cytokine profile of antigen-specific effector T cells.

Characterization of Giemsa dark- and light-band DNA

Using synchronized cultures of V79-8 Chinese hamster lung fibroblasts, we either alternately labeled early- and late-replicating DNA, or substituted one of these with bromodeoxyuridine to separate them in CsCl density gradients or to identify the bromodeoxyuridine-containing chromosome bands by fluorescence microscopy. The Giemsa light R bands were shown to replicate in the first half of S phase, and the dark G bands were shown to replicate in the last half of S phase. S phase was bimodal, with a distinct pause in the rate of DNA synthesis that separated the period of R-band DNA synthesis from that of G-band DNA synthesis. G-band DNA was found to be 3.2% richer in AT than R-band DNA. Surprisingly, G- and R-band DNA appeared equally transcriptionally active in that alternate labels in chromatin were digested with the same kinetics by DNAase I, and in reassociation experiments, total poly(A)+ RNA drove nick-translated G- and R-band DNA probes similarly. G- and R-band DNA also reassociated with identical kinetics, demonstrating that they contain equal proportions of all kinetic-complexity classes of sequences.

Urinary incontinence and depression

PURPOSE

Serotonergic neuronal systems have been implicated in anxiety and depression. Because descending serotonin pathways from the brain stem inhibit bladder contractions, we postulated that depression associated with altered serotonin function may predispose to urge incontinence. We demonstrate an association between depression and idiopathic urge incontinence.

MATERIALS AND METHODS

A total of 115 consecutive incontinent patients presenting to an incontinence clinic were compared to 80 continent controls. Patients were queried for a history of depression and completed a Beck Depression Inventory (BDI). Cases were classified by history and video urodynamics as genuine stress (36), urge (44) or mixed (35) incontinence.

RESULTS

A BDI of greater than 12 and/or a history of depression was noted in 30% of incontinent patients and 17% of controls (odds ratio 2.3, 95% confidence interval 1.0 to 5.0, p = 0.044). An abnormal BDI or history of depression was revealed in 60% of patients with idiopathic urge incontinence (p<0.001). Patients with stress or urge incontinence due to neuropathology or obstruction had no greater odds of having depression than continent controls.

CONCLUSIONS

These data suggest a strong association between depression and idiopathic urinary incontinence. This link may be due to altered serotonin function and may help explain the efficacy of serotonergic based antidepressants in the treatment of urge incontinence.

Proposal for a nomenclature for magnetic resonance imaging based measures of articular cartilage in osteoarthritis

OBJECTIVE

Magnetic resonance imaging (MRI) of articular cartilage has evolved to be an important tool in research on cartilage (patho)physiology and osteoarthritis (OA). MRI provides a wealth of novel and quantitative information, but there exists no commonly accepted terminology for reporting these metrics. The objective of this initiative was to propose a nomenclature for definitions and names to be used in scientific communications and to give recommendations as to which minimal methodological information should be provided when reporting MRI-based measures of articular cartilage in OA.

METHODS

An international group of experts with direct experience in MRI measurement of cartilage morphology or composition reviewed the existing literature. Through an iterative process that included a meeting with a larger group of scientists and clinicians (December 2nd, 2004, Chicago, IL, USA), they discussed, refined, and proposed a nomenclature for MRI-based measures of articular cartilage in OA.

RESULTS

The group proposes a nomenclature that describes: (1) the anatomical location and (2) the structural feature being measured, each name consisting of a metric variable combined with a tissue label. In addition, the group recommends minimal methodological information that should be described.

CONCLUSIONS

Utilization of this nomenclature should facilitate communication within the scientific community. Further, the uniform adoption of comprehensive nomenclature to describe quantitative MRI- features of articular cartilage should strengthen epidemiological, clinical, and pharmacological studies in OA.

Protease inhibitor combination therapies and perceptions of gay men regarding AIDS severity and the need to maintain safer sex

BACKGROUND

Advances in the treatment of HIV disease with protease inhibitor combination therapies have been widely documented in the media.

OBJECTIVES

To investigate perceptions concerning the severity of HIV/AIDS and the need to maintain safer sex practices in the light of recent HIV treatment advances.

METHODS

A survey eliciting demographic characteristics, HIV serostatus and treatment information, and HIV/AIDS severity and safer sex perceptions was administered to a community sample of 379 homo-/bisexual men who reported awareness of combination therapy regimens.

RESULTS

Ten per cent of all respondents agreed or strongly agreed with the statement that 'AIDS is now very nearly cured' and 13% felt that the threat of AIDS is less serious than in the past. HIV-positive men were more likely to perceive AIDS as a less serious threat or as very nearly cured. Overall, 8% of men in the sample indicated that they practice safer sex less often since new AIDS treatments came along; 18% of HIV-positive men on combination therapy regimens said they practice safer sex less frequently since treatments have advanced. Regardless of serostatus, nearly 20% of men indicated they would stop practicing safer sex if an AIDS cure was announced.

CONCLUSION

It is essential to integrate behavior change counseling into HIV treatment programs and to temper optimism concerning treatment advances with recognition that the threat of HIV/AIDS remains great.

Sensitive determination of cell number using the CyQUANT cell proliferation assay

We describe here the development and characterization of the CyQUANT cell proliferation assay, a highly sensitive, fluorescence-based microplate assay for determining numbers of cultured cells. The assay employs CyQUANT GR dye, which produces a large fluorescence enhancement upon binding to cellular nucleic acids that can be measured using standard fluorescein excitation and emission wavelengths. The fluorescence emission of the dye-nucleic acid complexes correlated linearly with cell number over a large range using a wide variety of cell types. Under the recommended assay conditions, standard curves were linear (r(2)>0.995), detecting as few as 10-50 cells and as many as 25,000-50,000 cells with a single dye concentration, depending on cell type. Increasing the dye concentration extended the linear range of the assay to 100,000-250,000 cells. Results of cell proliferation and growth inhibition studies with the assay were similar to those obtained in published studies using other standard assays. CyQUANT assay measurements of serum-stimulated cell proliferation correlated well with measurements made using [3H]-thymidine. Also, the assay was used to analyze cellular DNA or RNA content, with the addition of a nuclease digestion step to the protocol. The assay procedure is simple and convenient, with no wash steps, and is readily amenable to automation.

Magnetic resonance imaging of articular cartilage

Magnetic resonance imaging is the optimal modality for assessing articular cartilage because of superior soft tissue contrast, direct visualization of articular cartilage, and multiplanar capability. Despite these advantages, there has been disagreement as to the efficacy of magnetic resonance imaging of articular cartilage. The reason for this controversy is multifactorial but in part is attributable to the lack of the use of optimized pulse sequences for articular cartilage. The current authors will review the current state of the art of magnetic resonance imaging of articular cartilage and cartilage repair procedures, discuss future new directions in imaging strategies and methods being developed to measure cartilage thickness and volume measurements, and propose a magnetic resonance imaging protocol to evaluate cartilage that is achievable on most magnetic resonance scanners, vendor independent, practical (time and cost efficient), and accepted and used by a majority of musculoskeletal radiologists.

Nasal delivery of an adenovirus-based vaccine bypasses pre-existing immunity to the vaccine carrier and improves the immune response in mice

Pre-existing immunity to human adenovirus serotype 5 (Ad5) is common in the general population. Bypassing pre-existing immunity could maximize Ad5 vaccine efficacy. Vaccination by the intramuscular (I.M.), nasal (I.N.) or oral (P.O.) route with Ad5 expressing Ebola Zaire glycoprotein (Ad5-ZGP) fully protected naïve mice against lethal challenge with Ebola. In the presence of pre-existing immunity, only mice vaccinated I.N. survived. The frequency of IFN-γ+ CD8+ T cells was reduced by 80% and by 15% in animals vaccinated by the I.M. and P.O. routes respectively. Neutralizing antibodies could not be detected in serum from either treatment group. Pre-existing immunity did not compromise the frequency of IFN-γ+ CD8+ T cells (3.9±1% naïve vs. 3.6±1% pre-existing immunity, PEI) nor anti-Ebola neutralizing antibody (NAB, 40±10 reciprocal dilution, both groups). The number of INF-γ+ CD8+ cells detected in bronchioalveolar lavage fluid (BAL) after I.N. immunization was not compromised by pre-existing immunity to Ad5 (146±14, naïve vs. 120±16 SFC/million MNCs, PEI). However, pre-existing immunity reduced NAB levels in BAL by ∼25% in this group. To improve the immune response after oral vaccination, the Ad5-based vaccine was PEGylated. Mice given the modified vaccine did not survive challenge and had reduced levels of IFN-γ+ CD8+ T cells 10 days after administration (0.3±0.3% PEG vs. 1.7±0.5% unmodified). PEGylation did increase NAB levels 2-fold. These results provide some insight about the degree of T and B cell mediated immunity necessary for protection against Ebola virus and suggest that modification of the virus capsid can influence the type of immune response elicited by an Ad5-based vaccine.

Promoting prevention in primary care: controlled trial of low technology, low cost approach

A study is described in which three general practices were provided with low cost, low technology support from a "facilitator" and were compared with control practices in the ascertainment of major risk factors for cardiovascular disease in middle aged patients. Patients who were attending for a consultation with their general practitioners were recruited to make an appointment with a practice nurse for a health check, and this was compared with ordinary consultations in the control practices. Practices were helped by the facilitator to develop the nurse's role. During the study the increase between intervention and control practices in blood pressure recording was doubled and in the recording of smoking habit it was quadrupled, and there was a fivefold increase in the recording of weight. This model can be applied to other aspects of prevention and general practice care.

Meiotic gene conversion tract length distribution within the rosy locus of Drosophila melanogaster

Employing extensive co-conversion data for selected and unselected sites of known molecular location in the rosy locus of Drosophila. we determine the parameters of meiotic gene conversion tract length distribution. The tract length distribution for gene conversion events can be approximated by the equation P(L > or = n) = phi n where P is the probability that tract length (L) is greater than or equal to a specified number of nucleotides (n). From the co-conversion data, a maximum likelihood estimate with standard error for phi is 0.99717 +/- 0.00026, corresponding to a mean conversion tract length of 352 base pairs. (Thus, gene conversion tract lengths are sufficiently small to allow for extensive shuffling of DNA sequence polymorphisms within a gene). For selected site conversions there is a bias towards recovery of longer tracts. The distribution of conversion tract lengths associated with selected sites can be approximated by the equation P(L > or = n/ selected) = phi n(1 - n + n/phi), where P is now the probability that a selected site tract length (L) is greater than or equal to a specified number of nucleotides (n). For the optimal value of phi determined from the co-conversion analysis, the mean conversion tract length for selected sites is 706 base pairs. We discuss, in the light of this and other studies, the relationship between meiotic gene conversion and P element excision induced gap repair and determine that they are distinct processes defined by different parameters and, possibly, mechanisms.

ABO-incompatible marrow transplants

Seventeen patients with aplastic anemia or acute leukemia received transplants from donors who had major ABO incompatibilities. Antibody titers were decreased by plasma and whole blood exchanges prior to marrow infusion. All 17 patients were successfully engrafted, and there was one possible rejection in the patient with the highest pretransplant anti-A IgG titer. Nine of 17 patients are currently alive. A review was carried out of transplants performed in Seattle between HLA-matched siblings with aplastic anemia and leukemia. Two hundred forty-six evaluable patients with ABO-compatible donors were compared with 46 with minor ABO-incompatible donors. There was no effect of minor ABO incompatibility on graft rejection, incidence and severity of graft-versus-host disease, or survival.

Endothelin-1 stimulates cardiac fibroblast proliferation through activation of protein kinase C

After myocardial ischemia, circulating levels of the mitogen endothelin-1 (ET-1) increase. The effects of ET-1 on cardiac fibroblasts are poorly characterized. Therefore we examined the influence of ET-1 on cardiac fibroblast proliferation with a view to elucidating the signal transduction mechanisms underlying this effect. ET-1 (10 n m) stimulated [(3)H]thymidine incorporation and cell proliferation in cultured neonatal rat cardiac fibroblasts, consistent with its activity as a mitogen. We examined the role of protein kinase C (PKC) on this function. Inhibition of PKC activation with either chelerythrine (1 microm) or staurosporine (1 n m) attenuated ET-1-induced increases in DNA synthesis and cell number. Downregulation of PKC by chronic pretreatment with 10 n m phorbol 12-myristate 13-acetate (PMA) also prevented ET-1-induced mitogenesis. In contrast to previous reports that cardiac fibroblast proliferation stimulated by angiotensin II acts independently of PKC, the ET-1 mediated mitogenic effect requires activation of PKC in these cells. Findings in adult rat cardiac fibroblasts were identical. In addition, we noted that concurrent treatment with the pro-inflammatory cytokine interleukin 1 beta which, like ET-1, is released after myocardial ischemia, attenuated the ET-1-induced increases in DNA synthesis and cell number. This effect was not mediated through a nitric oxide synthase pathway.

Choosing Wisely in the UK: the Academy of Medical Royal Colleges' initiative to reduce the harms of too much medicine

A Malhotra and colleagues explain how and why a US initiative to get doctors to stop using interventions with no benefit is being brought to the UK

Phosphatidylserine Sensing by TAM Receptors Regulates AKT-Dependent Chemoresistance and PD-L1 Expression

Tyro3, Axl, and Mertk (collectively TAM receptors) are three homologous receptor tyrosine kinases that bind vitamin K-dependent endogenous ligands, Protein S (ProS), and growth arrest-specific factor 6 (Gas6), and act as bridging molecules to promote phosphatidylserine (PS)-mediated clearance of apoptotic cells (efferocytosis). TAM receptors are overexpressed in a vast array of tumor types, whereby the level of expression correlates with the tumor grade and the emergence of chemo- and radioresistance to targeted therapeutics, but also have been implicated as inhibitory receptors on infiltrating myeloid-derived cells in the tumor microenvironment that can suppress host antitumor immunity. In the present study, we utilized TAM-IFNγR1 reporter lines and expressed TAM receptors in a variety of epithelial cell model systems to show that each TAM receptor has a unique pattern of activation by Gas6 or ProS, as well as unique dependency for PS on apoptotic cells and PS liposomes for activity. In addition, we leveraged this system to engineer epithelial cells that express wild-type TAM receptors and show that although each receptor can promote PS-mediated efferocytosis, AKT-mediated chemoresistance, as well as upregulate the immune checkpoint molecule PD-L1 on tumor cells, Mertk is most dominant in the aforementioned pathways. Functionally, TAM receptor-mediated efferocytosis could be partially blocked by PS-targeting antibody 11.31 and Annexin V, demonstrating the existence of a PS/PS receptor (i.e., TAM receptor)/PD-L1 axis that operates in epithelial cells to foster immune escape. These data provide a rationale that PS-targeting, anti-TAM receptor, and anti-PD-L1-based therapeutics will have merit as combinatorial checkpoint inhibitors.Implications: Many tumor cells are known to upregulate the immune checkpoint inhibitor PD-L1. This study demonstrates a role for PS and TAM receptors in the regulation of PD-L1 on cancer cells. Mol Cancer Res; 15(6); 753-64. ©2017 AACR.

A healthy bladder: a consensus statement

A panel of experts in urology, urogynecology, nursing, and behavioral therapy convened in 2010 to discuss the importance of a healthy bladder on overall health. They determined that a consensus statement was necessary to raise awareness among the general public, healthcare providers, payors, and policymakers, with the goals of minimizing the impact of poor bladder health and stimulating primary prevention of bladder conditions. In this statement, 'healthy' bladder function is described, as well as internal and external factors that influence bladder health. It is suggested that primary prevention strategies should be aimed at providing education regarding normal lower urinary tract structures and functioning to the public, including patients and healthcare providers. This education may promote the achievement of optimal bladder health by increasing healthy bladder habits and behaviors, awareness of risk factors, healthcare seeking, and clinician engagement and reducing stigma and other barriers to treatment. Promoting optimal bladder health may reduce the personal, societal and economic impact of bladder conditions, including anxiety and depression and costs associated with conditions or diseases and their treatment. While adopting healthy bladder habits and behaviors and behaviors may improve or maintain bladder health, it is important to recognize that certain symptoms may indicate the presence of conditions that require medical attention; many bladder conditions are treatable with a range of options for most bladder conditions. Lastly, the authors propose clinical directives based on persuasive and convergent research to improve and maintain bladder health. The authors hope that this statement will lead to promotion and achievement of optimal bladder health, which may improve overall health and help minimize the effects of bladder conditions on the public, healthcare professionals, educators, employers, and payors. The advisors are in consensus regarding the recommendations for improving and maintaining bladder health presented herein.

Lamellar body formation in normal and surfactant protein B-deficient fetal mice

Surfactant protein B (SP-B) -/- mice die of lethal respiratory distress syndrome shortly after birth. Alveolar type II epithelial cells in SP-B-deficient mice are characterized by a complete absence of lamellar bodies, the intracellular storage form of pulmonary surfactant, and the presence of inclusions containing numerous small vesicles and electron-dense masses. The present study was undertaken to characterize the formation of these inclusions during fetal lung development and clarify their relationship to lamellar bodies. In wild-type and SP-B +/- mice, small lamellar bodies with loosely organized lamellae and distinct limiting membranes were first detected on day 16 to 16.5 of gestation. SP-B -/- mice were readily identified on day 16 by the absence of immature lamellar bodies, the appearance of vesicular inclusions similar to those previously described in late gestation SP-B -/- mice, and the accumulation of misprocessed SP-C protein. Vesicular inclusions were rarely detected in SP-B +/- mice and were never detected in wild-type littermates. Classical multivesicular bodies were observed fusing with lamellar bodies in wild-type mice, and with the vesicular inclusions in SP-B -/- mice that occasionally contained a few membrane lamellae. On day 18, the airways of SP-B -/- mice lacked tubular myelin and were filled with vesicles and electron-dense masses, suggesting that the contents of the vesicular inclusions were secreted. Taken together, these observations suggest that vesicular inclusions in SP-B -/- mice are disorganized lamellar bodies in which the absence of SP-B leads to failure to package surfactant phospholipids into concentric lamellae.

The professional socialization of diploma of higher education in nursing students (Project 2000): a longitudinal qualitative study

This paper presents a new theory of professional socialization in relation to diploma of higher education in nursing students (Project 2000). It was derived from a 3-year, grounded theory, longitudinal study exploring the effects of supernumerary status and mentorship on students undertaking practice placements. A purposive sample of 17 students was used. Ten students volunteered to be interviewed on five separate occasions throughout their course and to keep a diary to record their experiences of mentorship during their practice placements. Their diary acted as an aide memoir during their tape-recorded interviews. The other seven students participated by diary only and kept written accounts of their experiences of being supernumerary and having a mentor whilst on practice placements. Data were analysed with the aid of NUD.IST and subjected to the constant comparative method of analysis. Findings indicate that the mentor is the linchpin of the students' experience and that some students develop intuition much earlier than previous work has stated.

Cost-effectiveness of mandatory stress testing in chest pain center patients

STUDY OBJECTIVE

To determine whether emergency patients with acute chest pain and low suspicion of acute myocardial infarction (AMI) can be managed cost-effectively and safely in a dedicated chest pain center (CPC) that incorporates mandatory stress testing.

METHODS

We assembled a prospective observational case series of consecutive adult patients transferred from the emergency department to a nine-bed, 23-hour CPC in a 564-bed community hospital from January 13 through May 31, 1994. In our institution, all emergency patients with acute nontraumatic chest pain of unclear origin, suggestive of myocardial ischemia but with a low probability of AMI, are transferred to the CPC for further evaluation. All patients in whom AMI is ruled out undergo individually appropriate cardiac diagnostic testing in accordance with CPC clinical guidelines. Patients with end-stage coronary artery disease transferred to the CPC for a "rule-out" protocol only did not undergo further diagnostic testing. Admitted and discharged patients were followed through chart review and telephone survey, respectively.

RESULTS

Of the 502 patients transferred to the CPC, 477 (95%) completed follow-up at 14 days. Four hundred ten (86%) were discharged home. Those discharged after diagnostic evaluation yielded negative findings had 100% survival and zero diagnosis of AMI at 5-month follow-up. Overall mortality and incidence of AMI on long-term follow-up for all patients transferred to the CPC were .4% and .2%, respectively. Sixty-seven patients (13%) were admitted from the CPC, of whom 44 (66%) had a final diagnosis of ischemic heart disease (IHD) or AMI. Twenty-four patients with IHD (55%; 6% of stress-tested group) were identified only on further stress testing. Of these patients, seven underwent percutaneous transluminal coronary angioplasty or coronary artery bypass grafting during hospitalization. All were discharged home without major morbidity. Four hundred twenty-four patients (84%) underwent stress testing. The cost of mandatory stress testing to identify one patient with IHD after AMI was ruled out was $3,125. An average cost-per-case savings of 62% was achieved for each patient transferred to the CPC who would have been hospitalized before the inception of the CPC.

CONCLUSION

Mandatory stress testing is a safe, cost-effective, and valuable diagnostic and prognostic tool in CPC patients.

Facilitating prevention in primary care

We believe that many general practitioners would practice preventive medicine if they had the opportunity to organise their practice to do this. We therefore provided a "facilitator," who understands the work of a general practice, to help practices that were interested in prevention to set up programmes. She, for example, helped the primary care team to set up objectives, trained practice nurses to measure blood pressure, and set up a system to measure the progress of the programme.

Distinct mechanisms for K+ efflux, intoxication, and hemolysis by Bordetella pertussis AC toxin

Adenylate cyclase (AC) toxin from Bordetella pertussis delivers its catalytic domain to the interior of target cells where it converts host ATP to cAMP in a process referred to as intoxication. This toxin also hemolyzes sheep erythrocytes by a mechanism presumed to include pore formation and osmotic lysis. Intoxication and hemolysis appear at strikingly different toxin concentrations and evolve over different time scales, suggesting that different molecular processes may be involved. The present study was designed to test the hypothesis that intoxication and hemolysis occur by distinct mechanisms. Although the hemolytic activity of AC toxin has a lag of >1 h, intoxication starts immediately. Because of this difference, we sought a surrogate or precursor lesion that leads to hemolysis, and potassium efflux has been observed from erythrocytes treated with other pore-forming toxins. AC toxin elicits an increase in K+ efflux from sheep erythrocytes and Jurkat cells, a human T-cell leukemia line, that begins within minutes of toxin addition. The toxin concentration dependence along with the analysis of the time course suggest that toxin monomers are sufficient to elicit release of K+ and to deliver the catalytic domain to the cell interior. Hemolysis, on the other hand, is a highly cooperative event that likely requires a subsequent oligomerization of these individual units. Although induction of K+ efflux shares some structural and environmental requirements with both intoxication and hemolysis, it can occur under conditions in which intoxication is reduced or prevented. The data presented here suggest that the transmembrane pathway by which K+ is released is separate and distinct from the structure required for intoxication but may be related to, or a precursor of, that which is ultimately responsible for hemolysis.

Why are patients with acute stroke admitted to hospital?

Data on 515 consecutive patients registered with the Oxfordshire Community Stroke Project were used to compare the characteristics of those patients who were admitted to hospital within one month after their first stroke with those who remained in the community during that time. Twenty eight patients had their stroke while in hospital for other conditions, and of the remaining 487, 266 were admitted. Though patients with a severe neurological deficit were significantly more likely to be admitted, 47 out of 202 such patients were managed in the community. In a substudy of 162 consecutive patients the general practitioners' reasons for either arranging admission to hospital or continuing with community care in the first week after the stroke were ascertained. Sixty patients were admitted. The only reason for admission was diagnostic uncertainty in five cases (though this was a contributing factor in 25) and to provide nursing or general, non-medical care in 25. Patients who lived alone were more likely to be admitted. All 12 patients who presented directly to the casualty department were admitted, though only five had had a severe stroke. A stroke service that provides a facility for rapid outpatient and domiciliary diagnosis as well as a rapidly acting domiciliary nursing team might reduce the number of patients with stroke admitted to hospital without adversely affecting the quality of patient care: this should be properly evaluated.

Aggressive behaviour in patients with schizophrenia is associated with catechol-O-methyltransferase genotype

BACKGROUND

Evidence exists for an association between aggression and schizophrenia. Although the aetiology of aggression is multifactorial, three studies have reported associations between polymorphisms of the catechol-O-methyltransferase (COMT) gene and aggression in schizophrenia.

AIMS

To replicate these findings in a larger sample using the Overt Aggression Scale (OAS).

METHOD

A sample of 180 people with DSM-IV schizophrenia were rated for aggression using the OAS. Kruskal-Wallis and contingency table analyses were applied to the OAS results.

RESULTS

The high-activity homozygotes showed significantly higher scores of aggression, whereas the heterozygotes showed significantly lower scores. The odds ratio for aggression for the high-activity homozygotes was 2.07 (95% Cl=1.03-4.15), whereas that for the heterozygotes was 0.54 (95% Cl=0.30-1.00). CONCLUSIONS; The high-activity COMT homozygote confers a higher risk of recorded aggression in schizophrenia. Heterozygotes had a significantly lower risk, which may represent an example of heterosis/heterozygote advantage.