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1.
J Phys Conf Ser ; 1590(1)2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36582544

RESUMEN

This paper summarizes the status of a 3-year, NIH-funded research project to study the strength of high temperature superconductors under high circumferential hoop stress, in order to qualify these materials for high-field (> 1 GHz-class NMR magnets. The unique approach presented here is to spin test coils at high rotational speeds, approaching 100,000 rpm, in order to induce the necessary hoop stress. Thermal strain compatibility between the Bi-2212 wire and Inconel wire has been qualified, including thermal cycling. Assembly and testing of the first low-speed (< 30,000 rpm) rotor is now in process, and the design of second, higher speed (> 60,000 rpm) rotor, is also underway.

2.
Epidemiol Psychiatr Sci ; 27(1): 51-61, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-27763251

RESUMEN

AIMS: Within acute psychiatric inpatient services, patients exhibiting severely disturbed behaviour can be transferred to a psychiatric intensive care unit (PICU) and/or secluded in order to manage the risks posed to the patient and others. However, whether specific patient groups are more likely to be subjected to these coercive measures is unclear. Using robust methodological and statistical techniques, we aimed to determine the demographic, clinical and behavioural predictors of both PICU and seclusion. METHODS: Data were extracted from an anonymised database comprising the electronic medical records of patients within a large South London mental health trust. Two cohorts were derived, (1) a PICU cohort comprising all patients transferred from general adult acute wards to a non-forensic PICU ward between April 2008 and April 2013 (N = 986) and a randomly selected group of patients admitted to general adult wards within this period who were not transferred to PICU (N = 994), and (2) a seclusion cohort comprising all seclusion episodes occurring in non-forensic PICU wards within the study period (N = 990) and a randomly selected group of patients treated in these wards who were not secluded (N = 1032). Demographic and clinical factors (age, sex, ethnicity, diagnosis, admission status and time since admission) and behavioural precursors (potentially relevant behaviours occurring in the 3 days preceding PICU transfer/seclusion or random sample date) were extracted from electronic medical records. Mixed effects, multivariable logistic regression analyses were performed with all variables included as predictors. RESULTS: PICU cases were significantly more likely to be younger in age, have a diagnosis of bipolar disorder and to be held on a formal section compared with patients who were not transferred to PICU; female sex and longer time since admission were associated with lower odds of transfer. With regard to behavioural precursors, the strongest predictors of PICU transfer were incidents of physical aggression towards others or objects and absconding or attempts to abscond. Secluded patients were also more likely to be younger and legally detained relative to non-secluded patients; however, female sex increased the odds of seclusion. Likelihood of seclusion also decreased with time since admission. Seclusion was significantly associated with a range of behavioural precursors with the strongest associations observed for incidents involving restraint or shouting. CONCLUSIONS: Whilst recent behaviour is an important determinant, patient age, sex, admission status and time since admission also contribute to risk of PICU transfer and seclusion. Alternative, less coercive strategies must meet the needs of patients with these characteristics.


Asunto(s)
Servicios de Urgencia Psiquiátrica , Pacientes Internos , Unidades de Cuidados Intensivos , Trastornos Mentales/psicología , Servicios de Salud Mental , Aislamiento de Pacientes/psicología , Adulto , Factores de Edad , Estudios de Casos y Controles , Femenino , Investigación sobre Servicios de Salud , Humanos , Masculino , Trastornos Mentales/terapia , Persona de Mediana Edad , Factores Sexuales , Factores de Tiempo , Adulto Joven
3.
Nat Commun ; 7: 11042, 2016 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-27025894

RESUMEN

The high incidence of armed conflicts in biodiverse regions poses significant challenges in achieving international conservation targets. Because attitudes towards risk vary, we assessed different strategies for protected area planning that reflected alternative attitudes towards the risk of armed conflicts. We find that ignoring conflict risk will deliver the lowest return on investment. Opting to completely avoid conflict-prone areas offers limited improvements and could lead to species receiving no protection. Accounting for conflict by protecting additional areas to offset the impacts of armed conflicts would not only increase the return on investment (an effect that is enhanced when high-risk areas are excluded) but also increase upfront conservation costs. Our results also demonstrate that fine-scale estimations of conflict risk could enhance the cost-effectiveness of investments. We conclude that achieving biodiversity targets in volatile regions will require greater initial investment and benefit from fine-resolution estimates of conflict risk.


Asunto(s)
Conflictos Armados , Actitud , Conservación de los Recursos Naturales , Biodiversidad , Factores de Riesgo , Incertidumbre
4.
Epidemiol Psychiatr Sci ; 25(2): 181-93, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25703270

RESUMEN

BACKGROUND: Aims of this study are to explore the associations of readmission to psychiatric hospital over time, to develop a statistical model for early readmission to psychiatric hospital and to assess the feasibility of predicting early readmission. METHOD: The sample comprised 7891 general psychiatric discharges in South London, taken from a large anonymised repository of electronic patient records. We initially explored time to readmission using Cox regression - this included investigation of time-dependent effects. Subsequently, we used logistic regression to create a predictive model for 90-day readmission. We investigated the effect on readmission of a set of variables that included demographic variables, diagnosis and legal status during the index admission, previous service use, housing variables and individual item scores on the Health of the Nation Outcome Scales (HoNOS) at admission and at discharge. RESULTS: Fifteen per cent of those discharged were readmitted within 90 days. Cox regression demonstrated that the estimated baseline hazard of readmission declined steeply after discharge and that the effects of several predictors, especially diagnosis, changed over time - most notably, personality disorder was associated with increased readmission relative to schizophrenia at the time of discharge, but did not significantly differ by 1-year postdischarge. In the logistic regression, increased readmission was associated with personality disorder diagnosis; shorter length of the index admission (excepting zero length admissions); number of discharges in the preceding 2 years; and having a high score at discharge on the HoNOS overactive and aggressive behaviour item, cognitive problems item or hallucinations and delusions items. Detention under Section 3 or a forensic section of the Mental Health Act during the index admission was associated with reduced readmission. The coefficient of discrimination for the logistic regression, which is equivalent to r 2, was 0.04 and the estimated area under the receiver operating curve was 0.65. CONCLUSIONS: The association found between early readmission and personality disorder diagnosis merits further investigation, as does the possible trade-off between reduction in length of stay and increased readmission. Other novel findings such as the associations found with HoNOS item scores also merit replication. As with previous studies, we found that the rate of readmission declines steeply after hospital discharge, so that the period immediately subsequent to discharge is a period of comparatively high risk. However, prediction of early readmission within this high-risk group remains challenging - it seems most likely that many unmeasured influences operate subsequent to the time of discharge.


Asunto(s)
Hospitales Psiquiátricos , Readmisión del Paciente , Trastornos de la Personalidad , Hospitalización , Humanos , Londres , Alta del Paciente , Factores de Riesgo
5.
Transl Psychiatry ; 5: e698, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26670283

RESUMEN

We sought to test the hypothesis that the rs1344706 A allele will be associated with worse clinical outcome in first-episode psychosis. A data linkage was set up between a large systematic study of first-episode psychosis and an electronic health-record case register at the South London and Maudsley NHS Foundation Trust--a large provider of secondary mental-health care. A sample of 291 patients, who presented with a first psychotic episode (ICD10 diagnoses F20-29 or F30-33) and in whom the rs1344706 genotype had been assayed, were followed to examine the duration of mental-health in-patient care during the 2 years following first service contact, as a primary outcome. Secondary outcome measures were whether or not an in-patient episode occurred and the number of in-patient episodes during this period. A strong association was found between the number of rs1344706 A alleles and the cumulative duration of mental-health in-patient stay over the 2 years since initial presentation. In the 84.2% who experienced an in-patient episode during this period, the mean duration of admission was an additional 38 days for each A allele increment. Therefore, in addition to its potential role as a risk factor for psychosis, the ZNF804A rs1344706 A allele is associated with worse clinical outcome.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Factores de Transcripción de Tipo Kruppel/genética , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Trastornos Psicóticos/genética , Esquizofrenia/genética , Adolescente , Adulto , Anciano , Femenino , Estudio de Asociación del Genoma Completo/estadística & datos numéricos , Humanos , Londres , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Adulto Joven
6.
BMC Emerg Med ; 15: 15, 2015 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-26174170

RESUMEN

BACKGROUND: Self-harm is a significant public health concern in the UK. This is reflected in the recent addition to the English Public Health Outcomes Framework of rates of attendance at Emergency Departments (EDs) following self-harm. However there is currently no source of data to measure this outcome. Routinely available data for inpatient admissions following self-harm miss the majority of cases presenting to services. We aimed to investigate (i) if a dataset of ED presentations could be produced using a combination of routinely collected clinical and administrative data and (ii) to validate this dataset against another one produced using methods similar to those used in previous studies. METHODS: Using the Clinical Record Interactive Search system, the electronic health records (EHRs) used in four EDs were linked to Hospital Episode Statistics to create a dataset of attendances following self-harm. This dataset was compared with an audit dataset of ED attendances created by manual searching of ED records. The proportion of total cases detected by each dataset was compared. RESULTS: There were 1932 attendances detected by the EHR dataset and 1906 by the audit. The EHR and audit datasets detected 77% and 76 of all attendances respectively and both detected 82% of individual patients. There were no differences in terms of age, sex, ethnicity or marital status between those detected and those missed using the EHR method. Both datasets revealed more than double the number of self-harm incidents than could be identified from inpatient admission records. CONCLUSIONS: It was possible to use routinely collected EHR data to create a dataset of attendances at EDs following self-harm. The dataset detected the same proportion of attendances and individuals as the audit dataset, proved more comprehensive than the use of inpatient admission records, and did not show a systematic bias in those cases it missed.


Asunto(s)
Conjuntos de Datos como Asunto , Servicio de Urgencia en Hospital/estadística & datos numéricos , Conducta Autodestructiva/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Registros Electrónicos de Salud , Femenino , Humanos , Almacenamiento y Recuperación de la Información , Londres/epidemiología , Masculino , Persona de Mediana Edad , Adulto Joven
7.
Epidemiol Psychiatr Sci ; 24(5): 402-14, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24978136

RESUMEN

AIMS: There has been little research into the facilitated discharge (FD) function of Home Treatment Teams (HTTs). We aimed to explore and describe the prevalence and associations of FD and to estimate its effects on bed days during the index admission (length of stay corrected for ward leave) and on readmission. METHODS: Descriptive and regression analyses of data collected by South London and Maudsley NHS Foundation Trust on discharges from its general psychiatric wards, with multiple imputation of missing covariate values. RESULTS: Overall, 29% of our sample of 7891 hospital admissions involved a FD. FD was associated with female gender, diagnosis of a severe mental illness, previous home treatment, having a longer previous admission, neither being discharged to a new address nor to a care home, having no other community team and having HoNOS item scores consistent with an active depressive or psychotic mental illness. In the regression analysis, FD was associated with 4.0 fewer bed days (95% confidence interval -6.7 to -1.3; p = 0.0004). There was no effect on readmission. CONCLUSIONS: Our analysis provides some support for the effectiveness of FD in slightly reducing the time spent in hospital and suggests that this may be achieved without increasing the rate of readmission. Further studies in this area are important, especially given existing research that suggests that the introduction of HTTs in England and Wales was associated with little or no change in service utilisation.

8.
Br J Psychiatry ; 204(6): 480-5, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24627298

RESUMEN

BACKGROUND: Attempts have been made to improve the efficiency of in-patient acute care. A novel method has been the development of a 'triage system' in which patients are assessed on admission to develop plans for discharge or transfer to an in-patient ward. AIMS: To compare a triage admission system with a traditional system. METHOD: Length of stay and readmission data for all admissions in a 1-year period between the two systems were compared using the participating trust's anonymised records. RESULTS: Despite reduced length of stay on the actual triage ward, the average length of stay was not reduced and the triage system did not lead to a greater number of readmissions. There was no significant difference in costs between the two systems. CONCLUSIONS: Based on our findings we cannot conclude that the triage system reduced length of stay, but we can conclude that it does not increase the number of readmissions as some have feared.


Asunto(s)
Eficiencia Organizacional/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Triaje/métodos , Servicio de Urgencia en Hospital/organización & administración , Servicio de Urgencia en Hospital/estadística & datos numéricos , Inglaterra , Hospitales Psiquiátricos/organización & administración , Hospitales Psiquiátricos/estadística & datos numéricos , Hospitales Urbanos/organización & administración , Hospitales Urbanos/estadística & datos numéricos , Humanos , Alta del Paciente , Readmisión del Paciente/estadística & datos numéricos , Triaje/estadística & datos numéricos
10.
Biomaterials ; 31(34): 8864-71, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20810163

RESUMEN

Because of its low profile and biologically inert behavior, thin film nitinol (TFN) is ideally suited for use in construction of endovascular devices. We have developed a surface treatment for TFN designed to minimize platelet adhesion by creating a superhydrophilic surface. The hemocompatibility of expanded polytetrafluorethylene (ePTFE), untreated thin film nitinol (UTFN), and a surface treated superhydrophilic thin film nitinol (STFN) was compared using an in vitro circulation model with whole blood under flow conditions simulating a moderate arterial stenosis. Scanning electron microscopy analysis showed increased thrombus on ePTFE as compared to UTFN or STFN. Total blood product deposition was 6.3 ± 0.8 mg/cm(2) for ePTFE, 4.5 ± 2.3 mg/cm(2) for UTFN, and 2.9 ± 0.4 mg/cm(2) for STFN (n = 12, p < 0.01). ELISA assay for fibrin showed 326 ± 42 µg/cm(2) for ePTFE, 45.6 ± 7.4 µg/cm(2) for UTFN, and 194 ± 25 µg/cm(2) for STFN (n = 12, p < 0.01). Platelet deposition measured by fluorescent intensity was 79,000 20,000 AU/mm(2) for ePTFE, 810 ± 190 AU/mm(2) for UTFN, and 1600 ± 25 AU/mm(2) for STFN (n = 10, p < 0.01). Mass spectrometry demonstrated a larger number of proteins on ePTFE as compared to either thin film. UTFN and STFN appear to attract significantly less thrombus than ePTFE. Given TFN's low profile and our previously demonstrated ability to place TFN covered stents in vivo, it is an excellent candidate for use in next-generation endovascular stents grafts.


Asunto(s)
Aleaciones/farmacología , Estenosis Coronaria/fisiopatología , Hemorreología/efectos de los fármacos , Ensayo de Materiales/métodos , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Proteínas Sanguíneas/química , Proteínas Sanguíneas/metabolismo , Fibrina/metabolismo , Humanos , Espectrometría de Masas , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Trombosis/patología
11.
J Biomed Mater Res A ; 90(2): 586-94, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18563822

RESUMEN

Modification of the chemistry and surface topography of nanophase ceramics was used to provide biomaterial formulations designed to direct the adhesion and proliferation of human mesenchymal stem cells (HMSCs). HMSC adhesion was dependent upon both the substrate chemistry and grain size, but not on surface roughness or crystal phase. Specifically, cell adhesion on alumina and hydroxyapatite was significantly reduced on the 50 and 24 nm surfaces, as compared with the 1500 and 200 nm surfaces, but adhesion on titania substrates was independent of grain size. HMSC proliferation was minimal on the 50 and 24 nm substrates of any chemistry tested, and thus significantly lower than the densities observed on either the 1500 or 200 nm surfaces after 3 or more consecutive days of culture. Furthermore, HMSC proliferation was enhanced on the 200 nm substrates, compared with results obtained on the 1500 nm substrates after 7 or more days of culture. HMSC proliferation was independent of both substrate surface roughness and crystal phase. Rat osteoblast and fibroblast adhesion and proliferation exhibited similar trends to that of HMSCs on all substrates tested. These results demonstrated the potential of nanophase ceramic surfaces to modulate functions of HMSCs, which are pertinent to biomedical applications such as implant materials and devices.


Asunto(s)
Cerámica/química , Células Madre Mesenquimatosas/citología , Nanotecnología/métodos , Células Madre/citología , Adhesión Celular , Proliferación Celular , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Nanopartículas/química , Osteoblastos/metabolismo , Tamaño de la Partícula , Propiedades de Superficie
13.
Thorax ; 60(4): 331-4, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15790990

RESUMEN

BACKGROUND: A study was undertaken to assess the prevalence of reported respiratory symptoms in a population aged over 75 years and their association with mortality. METHODS: A total of 14 458 people aged 75 years and over participating in a trial of health screening of older people in general practice answered questions on three respiratory symptoms: cough, sputum production, and wheeze. The association of symptoms with mortality was examined for all cause and respiratory causes of death taking account of potential confounders. RESULTS: Coughing up phlegm in winter mornings had a prevalence of 27.0% (95% confidence interval (CI) 26.8 to 27.2). Those with this symptom had an adjusted hazard ratio for all cause mortality of 1.35 (95% CI 1.21 to 1.50), p<0.001 and for respiratory specific mortality of 2.01 (95% CI 1.66 to 2.41), p<0.001. Phlegm at any time of the day in winter had a prevalence of 16.5% (95% CI 16.3 to 16.7) with hazard ratios for all cause and respiratory specific mortality of 1.28 (95% CI 1.15 to 1.42) and 2.28 (95% CI 1.92 to 2.70), p<0.001. Wheeze or whistling from the chest had a prevalence of 14.3% (95% CI 14.1 to 14.5) with hazard ratios of 1.45 (95% CI 1.31 to 1.61) and 2.86 (95% CI 2.45 to 3.35), p<0.001. CONCLUSIONS: The prevalence of respiratory symptoms is widespread among elderly people and their presence is a strong predictor of mortality.


Asunto(s)
Trastornos Respiratorios/mortalidad , Anciano , Anciano de 80 o más Años , Intervalos de Confianza , Femenino , Humanos , Masculino , Prevalencia , Modelos de Riesgos Proporcionales , Factores de Riesgo , Estaciones del Año , Reino Unido/epidemiología
15.
BMC Health Serv Res ; 2(1): 21, 2002 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-12398790

RESUMEN

BACKGROUND: The benefit of regular multidimensional assessment of older people remains controversial. The majority of trials have been too small to produce adequate evidence to inform policy. Despite the lack of a firm evidence base, UK primary care practitioners (general practitioners) are required to offer an annual health check to patients aged 75 years and over. DESIGN: Cluster-randomised factorial trial in primary care comparing a package of assessments (i) universal versus targeted assessment and (ii) management by the primary care team (PC) or a multidisciplinary geriatric assessment team (GM). The unit of randomization is the general practice. METHODS: Older people aged 75 and over eligible for the over 75s health check and excluding those in nursing homes or terminally ill were invited to participate. All participants receive a brief assessment covering all areas of the over 75s check. In the universal arm all participants also receive a detailed health and social assessment by a study nurse while in the targeted arm only participants with a pre-determined number and range of problems at the brief assessment go on to have the detailed assessment. The study nurse follows a standard protocol based on results and responses in the detailed assessment to make referrals to (i) the randomised management team (PC or GM) (ii) other medical services, health care workers or agencies (iii) emergency referrals to the GP. The main outcomes are mortality, hospital and institutional admissions and quality of life. 106 practices and 33,000 older people have been recruited to the trial.


Asunto(s)
Medicina Familiar y Comunitaria/normas , Evaluación Geriátrica/métodos , Grupo de Atención al Paciente , Examen Físico/métodos , Atención Primaria de Salud/normas , Anciano , Anciano de 80 o más Años , Análisis por Conglomerados , Medicina Familiar y Comunitaria/legislación & jurisprudencia , Hospitalización/estadística & datos numéricos , Humanos , Mortalidad , Atención Primaria de Salud/legislación & jurisprudencia , Calidad de Vida , Derivación y Consulta , Medicina Estatal/legislación & jurisprudencia , Medicina Estatal/normas , Encuestas y Cuestionarios , Reino Unido/epidemiología
16.
Br J Ophthalmol ; 86(7): 795-800, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12084753

RESUMEN

AIMS: To measure the prevalence of visual impairment in a large representative sample of people aged 75 years and over participating in the MRC trial of assessment and management of older people in the community. METHODS: 53 practices in the MRC general practice research framework. Data were obtained from 14 600 participants aged 75 years and older. Prevalence of visual impairment overall (binocular visual acuity <6/18) which was categorised separately into low vision (binocular visual acuity <6/18-3/60) or blindness (binocular visual acuity of <3/60). The prevalence of binocular acuity <6/12 was presented for comparison with other studies. Visual acuity was measured using Glasgow acuity charts; glasses, if worn, were not removed. RESULTS: Visual acuity was available for 14 600 people out of 21 241 invited (69%). Among people with visual acuity data, 12.4% overall (1803) were visually impaired (95% confidence intervals 10.8% to 13.9%); 1501 (10.3%) were categorised as having low vision (8.7% to 11.8%), and 302 (2.1%) were blind (1.8% to 2.4%). At ages 75-79, 6.2% of the cohort were visually impaired (5.1% to 7.3%) with 36.9% at age 90+ (32.5% to 41.3%). At ages 75-79, 0.6% (0.4% to 0.8%) of the study population were blind, with 6.9% (4.8% to 9.0%) at age 90+. In multivariate regression, controlling for age, women had significant excess risk of visual impairment (odds ratio 1.43, 95% confidence interval 1.29 to 1.58). Overall, 19.9% of study participants had a binocular acuity of less than 6/12 (17.8% to 22.0%). CONCLUSION: The results from this large study show that visual impairment is common in the older population and that this risk increases rapidly with advancing age, especially for women. A relatively conservative measure of visual impairment was used. If visual impairment had been defined as visual acuity of <6/12 (American definition of visual impairment), the age specific prevalence estimates would have increased by 60%.


Asunto(s)
Evaluación Geriátrica , Trastornos de la Visión/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Humanos , Oportunidad Relativa , Prevalencia , Análisis de Regresión , Riesgo , Factores Sexuales , Reino Unido/epidemiología
17.
Environ Pollut ; 111(3): 479-91, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11202753

RESUMEN

Potato (Solanum tuberosum cv. Bintje) was grown in open-top chambers under three carbon dioxide (ambient and seasonal mean concentrations of 550 and 680 mumol mol-1 CO2) and two ozone concentrations (ambient and an 8 h day-1 seasonal mean of 50 nmol mol-1 O3) between emergence and final harvest. Periodic non-destructive measurements were made and destructive harvests were carried out at three key developmental stages (24, 49 and 101 days after emergence) to establish effects on growth and tuber yield. Season-long exposure to elevated O3 reduced above-ground dry weight at final harvest by 8.4% (P < 0.05), but did not affect tuber yields. There was no significant interaction between CO2 and O3 for any of the growth and yield variables examined. Non-destructive analyses revealed no significant effect of elevated CO2 on plant height, leaf number or green leaf area ratio. However, destructive harvests at tuber initiation and 500 degrees Cd after emergence showed that above-ground dry weight (8 and 7% respectively) and tuber yield (88 and 44%) were significantly increased (P < 0.05) in the 550 mumol mol-1 CO2 treatment. Responses to 550 and 680 mumol mol-1 CO2 were not significantly different for most parameters examined, suggesting the existence of an upper limit to the beneficial influence of CO2 enrichment. Significant effects on above-ground dry weight and tuber yield were no longer apparent at final harvest, although tuber numbers were increased (P < 0.05) under elevated CO2, particularly in the smaller size categories. The results show that the O3 treatment imposed was insufficient to reduce tuber yields and that, although elevated CO2 enhanced crop growth during the early stages of the season, this beneficial effect was not sustained to maturity.


Asunto(s)
Agricultura , Contaminantes Atmosféricos/toxicidad , Dióxido de Carbono/farmacología , Ozono/toxicidad , Solanum tuberosum/efectos de los fármacos , Análisis de Varianza , Relación Dosis-Respuesta a Droga , India , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Distribución Aleatoria , Solanum tuberosum/crecimiento & desarrollo
19.
Gene ; 215(2): 345-59, 1998 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-9714834

RESUMEN

Recently, there have been several reports describing the cloning and characterization of the novel family of protein tyrosine phosphatase-like receptor molecules (known as IA-2 and PTP-NP/PTP-IAR/IA-2beta/phogrin), which may act as autoantigens in diabetes. Here, we report the molecular characterization and chromosomal localization of a new isoform of this family in brain termed PTP-NP-2 (for PTP-NP tyrosine phosphatase isoform), and its function in rat primary hippocampal neurons. PTP-NP-2 has 48% identity to IA-2. The principal difference between PTP-NP-2 and PTP-NP is a 17-amino-acid insert near the N-terminus of PTP-NP that is absent in PTP-NP-2. Genomic DNA analysis indicates that the 17-amino-acid insert is coded by a separate exon, suggesting that both IA-2beta and PTP-NP-2 are isoforms arising by alternate splicing of the same gene. Reverse transcriptase-PCR revealed that both isoforms are present in human SH-SY5Y neuroblastoma cells. PTP-NP-2 mRNA expression is highly restricted, with a 5.5-kb specific transcript in human fetal and adult brain and 5.5 and 3. 8 kb in human adult pancreas. SH-SY5Y neuroblastoma and U87-MG glioblastoma cells showed specific transcripts of 5.5 and 3.8kb, respectively, indicating the existence of several isoforms of this molecule in the nervous system. The human gene encoding PTP-NP-2 was assigned to human chromosome 7q22-qter using Southern blot analysis of genomic DNAs from rodent/human somatic hybrid cell lines. Confocal microscopy analyses of rat primary hippocampal neurons revealed that PTP-NP-2 is abundantly expressed on synaptic boutons in primary neurons. Wild-type PTP-NP-2 showed no measurable tyrosine phosphatase activity using an in-vitro pNPP assay. Examination of the PTP-NP-2 catalytic consensus sequence revealed that this sequence differed from the typical tyrosine phosphatase-domain consensus sequence by an alanine to aspartate change (amino acid 930). Mutation of aspartate 930 to alanine produced a catalytically active enzyme, suggesting that native PTP-NP and its isoform PTP-NP-2 are catalytically inactive receptor protein tyrosine phosphatase homologues. Taken together, these results indicate that the tyrosine phosphatase PTP-NP-2 is a new isoform of PTP-NP tyrosine phosphatase, is expressed on synaptic boutons and may participate in the regulation of synaptic bouton endocytosis.


Asunto(s)
Encéfalo/metabolismo , Cromosomas Humanos Par 7 , Glicoproteínas de Membrana/genética , Proteínas de la Membrana , Neuronas/metabolismo , Proteínas Tirosina Fosfatasas/genética , Sinapsis/metabolismo , Adulto , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Encéfalo/embriología , Mapeo Cromosómico , Femenino , Feto , Regulación del Desarrollo de la Expresión Génica , Glioblastoma , Hipocampo/metabolismo , Humanos , Masculino , Glicoproteínas de Membrana/biosíntesis , Glicoproteínas de Membrana/química , Modelos Moleculares , Datos de Secuencia Molecular , Neuroblastoma , Conformación Proteica , Proteínas Tirosina Fosfatasas/biosíntesis , Proteínas Tirosina Fosfatasas/química , Ratas , Proteínas Tirosina Fosfatasas Clase 8 Similares a Receptores , Transcripción Genética , Células Tumorales Cultivadas
20.
J Adolesc Health ; 21(4): 267-75, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9304459

RESUMEN

PURPOSE: To examine the association between communication with parents and self-harm in 14-19-year-old adolescents. METHODS: A total of 36 female and 16 male adolescents presenting to the accident and emergency department of a general hospital; 52 hospital-based controls were interviewed and studied using the following scales: Parent-Adolescent Communication Scale, Family Adaptability and Cohesion Evaluation Scale, Adolescent-Family Inventory of Life Events and Changes Scale, Children's Depression Index, and Nowicki-Strickland Locus of Control Scale. RESULTS: The absence of a family confidant was very strongly associated with adolescent self-harm. Despite controlling for a wide range of possible causal factors, poorer parent-adolescent communication remained strongly associated with self-harm. The effect of poorer communication on self-harm was strongest in the group with and internal locus of control. CONCLUSIONS: Impairment of communication between adolescents and their parents may be important in the origins of adolescent self-harm.


Asunto(s)
Comunicación , Relaciones Padres-Hijo , Psicología del Adolescente , Conducta Autodestructiva/etiología , Adolescente , Adulto , Composición Familiar , Femenino , Humanos , Masculino , Factores de Riesgo , Conducta Autodestructiva/psicología
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