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1.
Br J Surg ; 105(12): 1583-1590, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30238438

RESUMEN

BACKGROUND: The majority of lesions resulting in pathological nipple discharge are benign. Conventional surgery is undirected and targeting the causative lesion by duct endoscopy may enable more accurate surgery with fewer complications. METHODS: Patients requiring microdochectomy and/or major duct excision were randomized to duct endoscopy or no duct endoscopy before surgery. Primary endpoints were successful visualization of the pathological lesion in patients randomized to duct endoscopy, and a comparison of the causative pathology between the two groups. The secondary endpoint was to compare the specimen size between groups. RESULTS: A total of 68 breasts were studied in 66 patients; there were 31 breasts in the duct endoscopy group and 37 in the no-endoscopy group. Median age was 49 (range 19-81) years. Follow-up was 5·4 (i.q.r. 3·3-8·9) years in the duct endoscopy group and 5·7 (3·1-9·0) years in no-endoscopy group. Duct endoscopy had a sensitivity of 80 (95 per cent c.i. 52 to 96) per cent, specificity of 71 (44 to 90) per cent, positive predictive value of 71 (44 to 90) per cent and negative predictive value of 80 (52 to 96) per cent in identifying any lesion. There was no difference in causative pathology between the groups. Median volume of the surgical resection specimen did not differ between groups. CONCLUSION: Diagnostic duct endoscopy is useful for identifying causative lesions of nipple discharge. Duct endoscopy did not influence the pathological yield of benign or malignant diagnoses nor surgical resection volumes. Registered as INTEND II in CancerHelp UK clinical trials database (https://www.cancerresearchuk.org/about-cancer/find-a-clinical-trial/a-study-looking-at-changes-inside-the-breast-ducts-of-women-who-have-nipple-discharge).


Asunto(s)
Enfermedades de la Mama/cirugía , Endoscopía/métodos , Secreción del Pezón , Pezones/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos Ambulatorios/estadística & datos numéricos , Enfermedades de la Mama/patología , Neoplasias de la Mama/patología , Femenino , Humanos , Cuidados Intraoperatorios/métodos , Persona de Mediana Edad , Papiloma Intraductal/patología , Cuidados Preoperatorios/métodos , Resultado del Tratamiento , Adulto Joven
2.
Genes Immun ; 18(2): 88-94, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28275240

RESUMEN

Sarcoidosis is a complex disease of unknown etiology characterized by the presence of granulomatous inflammation. Though various immune system pathways have been implicated in disease, the relationship between the genetic determinants of sarcoidosis and other inflammatory disorders has not been characterized. Herein, we examined the degree of genetic pleiotropy common to sarcoidosis and other inflammatory disorders to identify shared pathways and disease systems pertinent to sarcoidosis onset. To achieve this, we quantify the association of common variant polygenic risk scores from nine complex inflammatory disorders with sarcoidosis risk. Enrichment analyses of genes implicated in pleiotropic associations were further used to elucidate candidate pathways. In European-Americans, we identify significant pleiotropy between risk of sarcoidosis and risk of asthma (R2=2.03%; P=8.89 × 10-9), celiac disease (R2=2.03%; P=8.21 × 10-9), primary biliary cirrhosis (R2=2.43%; P=2.01 × 10-10) and rheumatoid arthritis (R2=4.32%; P=2.50 × 10-17). These associations validate in African Americans only after accounting for the proportion of genome-wide European ancestry, where we demonstrate similar effects of polygenic risk for African-Americans with the highest levels of European ancestry. Variants and genes implicated in European-American pleiotropic associations were enriched for pathways involving interleukin-12, interleukin-27 and cell adhesion molecules, corroborating the hypothesized immunopathogenesis of disease.


Asunto(s)
Pleiotropía Genética , Inflamación/genética , Sarcoidosis/genética , Negro o Afroamericano/genética , Humanos , Inflamación/inmunología , Interleucina-12/inmunología , Interleucinas/inmunología , Herencia Multifactorial , Sarcoidosis/inmunología , Población Blanca/genética
3.
Psychol Med ; 46(8): 1581-96, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26966023

RESUMEN

Ecstasy/3,4-methylenedioxymethamphetamine (MDMA) use is proposed to cause damage to serotonergic (5-HT) axons in humans. Therefore, users should show deficits in cognitive processes that rely on serotonin-rich, prefrontal areas of the brain. However, there is inconsistency in findings to support this hypothesis. The aim of the current study was to examine deficits in executive functioning in ecstasy users compared with controls using meta-analysis. We identified k = 39 studies, contributing 89 effect sizes, investigating executive functioning in ecstasy users and polydrug-using controls. We compared function-specific task performance in 1221 current ecstasy users and 1242 drug-using controls, from tasks tapping the executive functions - updating, switching, inhibition and access to long-term memory. The significant main effect demonstrated overall executive dysfunction in ecstasy users [standardized mean difference (SMD) = -0.18, 95% confidence interval (CI) -0.26 to -0.11, Z = 5.05, p < 0.001, I 2 = 82%], with a significant subgroup effect (χ 2 = 22.06, degrees of freedom = 3, p < 0.001, I 2 = 86.4%) demonstrating differential effects across executive functions. Ecstasy users showed significant performance deficits in access (SMD = -0.33, 95% CI -0.46 to -0.19, Z = 4.72, p < 0.001, I 2 = 74%), switching (SMD = -0.19, 95% CI -0.36 to -0.02, Z = 2.16, p < 0.05, I 2 = 85%) and updating (SMD = -0.26, 95% CI -0.37 to -0.15, Z = 4.49, p < 0.001, I 2 = 82%). No differences were observed in inhibitory control. We conclude that this is the most comprehensive analysis of executive function in ecstasy users to date and provides a behavioural correlate of potential serotonergic neurotoxicity.


Asunto(s)
Consumidores de Drogas/psicología , Función Ejecutiva , N-Metil-3,4-metilenodioxianfetamina , Trastornos Relacionados con Sustancias/psicología , Estudios de Casos y Controles , Humanos , Inhibición Psicológica , Memoria a Largo Plazo , Pruebas Neuropsicológicas , Análisis y Desempeño de Tareas
4.
Psychol Med ; 45(2): 395-406, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25066866

RESUMEN

BACKGROUND: Cognitive deficits are well documented in ecstasy (3,4-methylenedioxymethamphetamine; MDMA) users, with such deficits being taken as evidence of dysregulation of the serotonin (5-hydroxytryptamine; 5-HT) system. More recently neuroimaging has been used to corroborate these deficits. The present study aimed to assess multitasking performance in ecstasy polydrug users, polydrug users and drug-naive individuals. It was predicted that ecstasy polydrug users would perform worse than non-users on the behavioural measure and this would be supported by differences in cortical blood oxygenation. METHOD: In the study, 20 ecstasy-polydrug users, 17 polydrug users and 19 drug-naive individuals took part. On day 1, drug use history was taken and questionnaire measures were completed. On day 2, participants completed a 20-min multitasking stressor while brain blood oxygenation was measured using functional near infrared spectroscopy (fNIRS). RESULTS: There were no significant differences between the three groups on the subscales of the multitasking stressor. In addition, there were no significant differences on self-report measures of perceived workload (NASA Task Load Index). In terms of mood, ecstasy users were significantly less calm and less relaxed compared with drug-naive controls. There were also significant differences at three voxels on the fNIRS, indicating decreased blood oxygenation in ecstasy users compared with drug-naive controls at voxel 2 (left dorsolateral prefrontal cortex), voxel 14 and voxel 16 (right dorsolateral prefrontal cortex), and compared with polydrug controls at V14. CONCLUSIONS: The results of the present study provide support for changes in brain activation during performance of demanding tasks in ecstasy polydrug users, which could be related to cerebral vasoconstriction.


Asunto(s)
Trastornos del Conocimiento/fisiopatología , Consumidores de Drogas/psicología , Alucinógenos/efectos adversos , N-Metil-3,4-metilenodioxianfetamina/efectos adversos , Oxígeno/sangre , Corteza Prefrontal/fisiopatología , Estrés Psicológico , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Drogas Ilícitas , Masculino , Espectroscopía Infrarroja Corta , Adulto Joven
5.
Parasitology ; 142(9): 1190-5, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26027539

RESUMEN

The nematode Angiostrongylus vasorum is becoming more widely recorded globally, and is of increasing concern as a cause of disease in dogs. Apparent geographic spread is difficult to confirm due to a lack of standardized disease recording systems, increasing awareness among veterinary clinicians, and recent improvements in diagnostic technologies. This study examines the hypothesis that A. vasorum has spread in recent years by repeating the methods of a previous survey of the fox population. The hearts and lungs of 442 foxes from across Great Britain were collected and examined by dissection and flushing of the pulmonary circulation and microscopic inspection of tracheal scrapes. Sampling and parasite extraction methods were identical to an earlier survey in 2005 to ensure comparability. Prevalence of A. vasorum was 18·3% (exact binomial confidence bounds 14·9-22·3), compared with 7·3% previously (5·3-9·9, n = 546), and had increased significantly in most regions, e.g. 7·4% in the Northern UK (previously zero) and 50·8% in the south-east (previously 23·2%). Other nematodes identified were Crenosoma vulpis (prevalence 10·8%, CI 8·1-14·2) and Eucoleus aerophilus (31·6%, CI 27·3-36·2). These data support the proposal that A. vasorum has increased in prevalence and has spread geographically in Great Britain.


Asunto(s)
Angiostrongylus/clasificación , Zorros , Infecciones por Strongylida/veterinaria , Animales , Cambio Climático , Infecciones por Strongylida/epidemiología , Reino Unido/epidemiología
6.
Mol Ther ; 22(2): 338-347, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24196577

RESUMEN

Duchenne muscular dystrophy is a monogenic disease potentially treatable by gene replacement. Use of recombinant adeno-associated virus (AAV) will ultimately require a vascular approach to broadly transduce muscle cells. We tested the impact of preexisting AAV antibodies on microdystrophin expression following vascular delivery to nonhuman primates. Rhesus macaques were treated by isolated limb perfusion using a fluoroscopically guided catheter. In addition to serostatus stratification, the animals were placed into one of the three immune suppression groups: no immune suppression, prednisone, and triple immune suppression (prednisone, tacrolimus, and mycophenolate mofetil). The animals were analyzed for transgene expression at 3 or 6 months. Microdystrophin expression was visualized in AAV, rhesus serotype 74 sero-negative animals (mean: 48.0 ± 20.8%) that was attenuated in sero-positive animals (19.6 ± 18.7%). Immunosuppression did not affect transgene expression. Importantly, removal of AAV binding antibodies by plasmapheresis in AAV sero-positive animals resulted in high-level transduction (60.8 ± 18.0%), which is comparable with that of AAV sero-negative animals (53.7 ± 7.6%), whereas non-pheresed sero-positive animals demonstrated significantly lower transduction levels (10.1 ± 6.0%). These data support the hypothesis that removal of AAV binding antibodies by plasmapheresis permits successful and sustained gene transfer in the presence of preexisting immunity (natural infection) to AAV.


Asunto(s)
Dependovirus/inmunología , Distrofina/genética , Expresión Génica , Vectores Genéticos/genética , Vectores Genéticos/inmunología , Plasmaféresis , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Dependovirus/genética , Genes Reporteros , Vectores Genéticos/administración & dosificación , Proteínas Fluorescentes Verdes/genética , Humanos , Macaca mulatta , Masculino , Músculo Esquelético/metabolismo , Plasmaféresis/métodos , Transducción Genética , Transgenes
7.
J Wound Care ; 24(6 Suppl): S18-20, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26075511

RESUMEN

Negative pressure wound therpay (NPWT) has revolutionised the management of chronic wounds, particularly pressure ulcers (PU). Frequently, PUs are too large to close primarily, so NPWT is used to assist in management on an outpatient basis. If not closely monitored, NPWT closure foam can be accidentally left in patients. Here we describe two cases where NPWT closure foam was left in patients resulting in persistent infections. Additionally, some suggestions of how to help avoid these should be 'never' events are provided.


Asunto(s)
Vendas Hidrocoloidales/efectos adversos , Cuerpos Extraños/etiología , Cuerpos Extraños/terapia , Terapia de Presión Negativa para Heridas/efectos adversos , Infección de Heridas/etiología , Infección de Heridas/terapia , Heridas y Lesiones/terapia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Cicatrización de Heridas
8.
Chempluschem ; : e202400164, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39383477

RESUMEN

The reaction of cyanogen azide with strained-ring containing primary and secondary amines led to the isolation of energetic molecules deriving their energy content from both strained rings as well as aminotetrazoles. Azo-coupling of these materials afforded novel high-nitrogen energetic materials of very high sensitivity. All compounds were chemically characterized by IR, NMR, single-crystal X-ray crystallography, and high-resolution mass spectrometry. Their impact and friction sensitivities were experimentally determined, and their energetic performances were calculated.

9.
Genes Immun ; 14(1): 13-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23151485

RESUMEN

A recent genome-wide association study in a German population and two subsequent studies in European populations found that a non-synonymous single-nucleotide polymorphism (SNP), rs1049550, within the annexin A11 (ANXA11) gene was associated with susceptibility to sarcoidosis. We sought to identify additional ANXA11 variants independently associated with sarcoidosis, determine whether any sarcoidosis-associated ANXA11 variants were associated with chest radiographic phenotypes, and explore human leukocyte antigen (HLA) SNP-SNP interactions with ANXA11. A total of 209 SNPs spanning 100 kb including the 5' promoter, coding, and 3' untranslated regions of ANXA11 were genotyped for 1689 sarcoidosis cases and 1252 controls. After adjustment for rs1049550, two additional novel ANXA11 sarcoidosis associations were identified only in African Americans--rs61860052 (odds ratio (OR)=0.62; 95% confidence interval (CI)=0.40-0.97) and rs4377299 (OR=1.31; 95% CI=1.06-1.63). These associations were more pronounced in radiologically-classified Scadding stage IV sarcoidosis cases. We also identified a significant SNP-SNP interaction between rs1049550 and a sarcoidosis risk SNP (rs9268839) near the HLA-DRA locus. This further genetic dissection of ANXA11 may provide additional insight into the immune dysregulation characteristic of sarcoidosis pathophysiology.


Asunto(s)
Anexinas/metabolismo , Negro o Afroamericano/genética , Polimorfismo de Nucleótido Simple , Sarcoidosis/genética , Población Blanca/genética , Anexinas/genética , Estudios de Casos y Controles , Estudios de Asociación Genética , Genoma Humano , Antígenos HLA/genética , Humanos , Regiones Promotoras Genéticas , Sarcoidosis/etnología
10.
Nat Genet ; 5(3): 225-9, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8275085

RESUMEN

Using gene targeting techniques, mice that have been generated with two germ-line p53 null alleles (homozygotes) develop normally but are highly susceptible to early onset spontaneous tumours. Here, we show that mice with a single null p53 allele (heterozygotes) produced in the same way are also susceptible to spontaneous tumours, but with a delayed onset compared to homozygotes. The most frequent tumour type in homozygotes was malignant lymphoma; in heterozygotes, osteosarcomas and soft tissue sarcomas predominated. Heterozygous mice treated with a liver carcinogen, dimethylnitrosamine, showed a decreased survival time in comparison to treated wild type mice, suggesting that the p53-deficient mice may be useful for some in vivo carcinogenesis assays.


Asunto(s)
Genes p53 , Neoplasias Experimentales/genética , Animales , Dimetilnitrosamina , Heterocigoto , Homocigoto , Masculino , Ratones , Ratones Endogámicos C57BL , Neoplasias Experimentales/inducido químicamente
11.
Midwifery ; 120: 103622, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36893551

RESUMEN

OBJECTIVE: Social support, an individual's social relationships (both online and offline), may provide protection against adverse mental health outcomes, such as anxiety and depression, which are high in women who have been hospitalised with high-risk pregnancy. This study explored the social support available to women at higher risk of preeclampsia during pregnancy by examining personal social networks. DESIGN: Semi-structured interviews were accompanied by social network mapping using the web-based social networking tool GENIE. SETTING: England. PARTICIPANTS: Twenty-one women were recruited, of whom 18 were interviewed both during pregnancy and postnatally between April 2019 and April 2020. Nineteen women completed maps pre-natally, 17 women completed maps pre-natally and post-natally. Women were taking part in the BUMP study, a randomised clinical trial that included 2441 pregnant individuals at higher risk of preeclampsia and recruited at a mean of 20 weeks' gestation from 15 hospital maternity units in England between November 2018 and October 2019. RESULTS: Women's social networks tightened during pregnancy. The inner network changed most dramatically postnatally with women reporting fewer network members. Interviews revealed networks were primarily 'real-life' rather than online social networks, with members providing emotional, informational, and practical support. Women with a high-risk pregnancy valued the relationships they developed with health professionals during pregnancy, and would like their midwife to have a more central role in their networks by providing informational and, where needed, emotional support. The social network mapping data supported the qualitative accounts of changing networks across high-risk pregnancy. CONCLUSION: Women with a high-risk pregnancy seek to build "nesting networks" to support them through pregnancy into motherhood. Different types of support are sought from trusted sources. Midwives can play a key role. PRACTICE IMPLICATIONS: As well as highlighting other potential needs during pregnancy and the ways in which they can be met, support from midwives has a key role. Through talking to women early in their pregnancy, signposting information and explaining ways to contact health professionals regarding informational or emotional support would fill a gap that currently is met by other aspects of their network.


Asunto(s)
Partería , Preeclampsia , Embarazo , Femenino , Humanos , Embarazo de Alto Riesgo , Apoyo Social , Red Social , Investigación Cualitativa
12.
Genes Immun ; 13(3): 232-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22189356

RESUMEN

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by autoantibody production and organ damage. Lupus nephritis (LN) is one of the most severe manifestations of SLE. Multiple studies reported associations between renal diseases and variants in the non-muscle myosin heavy chain 9 (MYH9) and the neighboring apolipoprotein L 1 (APOL1) genes. We evaluated 167 variants spanning MYH9 for association with LN in a multiethnic sample. The two previously identified risk variants in APOL1 were also tested for association with LN in European-Americans (EAs) (N = 579) and African-Americans (AAs) (N = 407). Multiple peaks of association exceeding a Bonferroni corrected P-value of P < 2.03 × 10(-3) were observed between LN and MYH9 in EAs (N = 4620), with the most pronounced association at rs2157257 (P = 4.7 × 10(-4), odds ratio (OR) = 1.205). A modest effect with MYH9 was also detected in Gullah (rs8136069, P = 0.0019, OR = 2.304). No association between LN and MYH9 was found in AAs, Asians, Amerindians or Hispanics. This study provides the first investigation of MYH9 in LN in non-Africans and of APOL1 in LN in any population, and presents novel insight into the potential role of MYH9 in LN in EAs.


Asunto(s)
Apolipoproteínas/genética , Negro o Afroamericano/genética , Lipoproteínas HDL/genética , Nefritis Lúpica/etnología , Nefritis Lúpica/genética , Proteínas Motoras Moleculares/genética , Cadenas Pesadas de Miosina/genética , Apolipoproteína L1 , Predisposición Genética a la Enfermedad , Humanos , Desequilibrio de Ligamiento , Polimorfismo de Nucleótido Simple , Población Blanca/genética
13.
Genes Immun ; 13(5): 380-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22476155

RESUMEN

Systemic lupus erythematosus (SLE) is an autoimmune disease with diverse clinical manifestations characterized by the development of pathogenic autoantibodies manifesting in inflammation of target organs such as the kidneys, skin and joints. Genome-wide association studies have identified genetic variants in the UBE2L3 region that are associated with SLE in subjects of European and Asian ancestry. UBE2L3 encodes an ubiquitin-conjugating enzyme, UBCH7, involved in cell proliferation and immune function. In this study, we sought to further characterize the genetic association in the region of UBE2L3 and use molecular methods to determine the functional effect of the risk haplotype. We identified significant associations between variants in the region of UBE2L3 and SLE in individuals of European and Asian ancestry that exceeded a Bonferroni-corrected threshold (P<1 × 10(-4)). A single risk haplotype was observed in all associated populations. Individuals harboring the risk haplotype display a significant increase in both UBE2L3 mRNA expression (P=0.0004) and UBCH7 protein expression (P=0.0068). The results suggest that variants carried on the SLE-associated UBE2L3 risk haplotype influence autoimmunity by modulating UBCH7 expression.


Asunto(s)
Predisposición Genética a la Enfermedad , Haplotipos , Lupus Eritematoso Sistémico/genética , Enzimas Ubiquitina-Conjugadoras/genética , Negro o Afroamericano/genética , Alelos , Pueblo Asiatico/genética , Femenino , Hispánicos o Latinos/genética , Humanos , Desequilibrio de Ligamiento , Lupus Eritematoso Sistémico/etnología , Masculino , Polimorfismo de Nucleótido Simple , Enzimas Ubiquitina-Conjugadoras/metabolismo , Población Blanca/genética
14.
Hum Psychopharmacol ; 27(2): 217-25, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22389086

RESUMEN

BACKGROUND: Research shows that cannabis users exhibit deficits in prospective memory (PM) and executive function, which persist beyond acute intoxication. However, many studies rely on self-reports of memory failures or use laboratory-based measures that may not mimic functional deficits in the real world. The present study aimed to assess real-world memory functioning. METHOD: Twenty cannabis-only users and 20 non-illicit drug users were recruited. Participants completed a substance use inventory and a mood scale, followed by a non-immersive virtual reality task assessing PM and executive functioning. The task involved the participant playing the role of an office worker for the day and performing routine office duties. A number of subscales were used to assess facets of executive function (planning, adaptive thinking, creative thinking, selection, prioritisation) and PM (time-based, event-based and action-based PM). RESULTS: Multivariate analysis of variance revealed cannabis users performed worse overall on the task, with poor performance on the planning, time-based PM and event-based PM subscales. In addition, indices of cannabis (length, dose, frequency, total use) were correlated with performance on these three subscales. CONCLUSIONS: The present study expands on previously established research, providing support for the cannabis-related deficits in PM and executive functioning, and the role of different aspects of cannabis use in these deficits.


Asunto(s)
Función Ejecutiva/efectos de los fármacos , Fumar Marihuana/fisiopatología , Trastornos de la Memoria/inducido químicamente , Memoria Episódica , Adolescente , Cannabis/química , Femenino , Humanos , Masculino , Fumar Marihuana/epidemiología , Análisis Multivariante , Factores de Tiempo , Adulto Joven
15.
J Res Natl Inst Stand Technol ; 116(6): 827-38, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-26989603

RESUMEN

In this paper we describe a novel long-term microhotplate temperature sensor calibration technique suitable for Built-In Self Test (BIST). The microhotplate thermal resistance (thermal efficiency) and the thermal voltage from an integrated platinum-rhodium thermocouple were calibrated against a freshly calibrated four-wire polysilicon microhotplate-heater temperature sensor (heater) that is not stable over long periods of time when exposed to higher temperatures. To stress the microhotplate, its temperature was raised to around 400 °C and held there for days. The heater was then recalibrated as a temperature sensor, and microhotplate temperature measurements were made based on the fresh calibration of the heater, the first calibration of the heater, the microhotplate thermal resistance, and the thermocouple voltage. This procedure was repeated 10 times over a period of 80 days. The results show that the heater calibration drifted substantially during the period of the test while the microhotplate thermal resistance and the thermocouple-voltage remained stable to within about plus or minus 1 °C over the same period. Therefore, the combination of a microhotplate heater-temperature sensor and either the microhotplate thermal resistance or an integrated thin film platinum-rhodium thermocouple can be used to provide a stable, calibrated, microhotplate-temperature sensor, and the combination of the three sensor is suitable for implementing BIST functionality. Alternatively, if a stable microhotplate-heater temperature sensor is available, such as a properly annealed platinum heater-temperature sensor, then the thermal resistance of the microhotplate and the electrical resistance of the platinum heater will be sufficient to implement BIST. It is also shown that aluminum- and polysilicon-based temperature sensors, which are not stable enough for measuring high microhotplate temperatures (>220 °C) without impractically frequent recalibration, can be used to measure the silicon substrate temperature if never exposed to temperatures above about 220 °C.

16.
J Exp Med ; 188(1): 119-31, 1998 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-9653089

RESUMEN

A null mutation was prepared in the mouse for CD18, the beta2 subunit of leukocyte integrins. Homozygous CD18 null mice develop chronic dermatitis with extensive facial and submandibular erosions. The phenotype includes elevated neutrophil counts, increased immunoglobulin levels, lymphadenopathy, splenomegaly, and abundant plasma cells in skin, lymph nodes, gut, and kidney. Very few neutrophils were found in spontaneously occurring skin lesions or with an induced toxic dermatitis. Intravital microscopy in CD18 null mice revealed a lack of firm neutrophil attachment to venules in the cremaster muscle in response to N-formyl- methionyl-leucyl-phenylalanine. A severe defect in T cell proliferation was found in the CD18 null mice when T cell receptors were stimulated either by staphylococcal enterotoxin A or by major histocompatibility complex alloantigens demonstrating a greater role of CD11/CD18 integrins in T cell responses than previously documented. The null mice are useful for delineating the functions of CD18 in vivo.


Asunto(s)
Antígenos CD18/genética , Síndrome de Deficiencia de Adhesión del Leucocito/etiología , Úlcera Cutánea/genética , Linfocitos T/inmunología , Animales , Antígenos CD18/fisiología , Adhesión Celular/genética , Adhesión Celular/fisiología , División Celular/genética , Modelos Animales de Enfermedad , Enterotoxinas/farmacología , Histocitoquímica , Humanos , Ratones , Ratones Noqueados , Neutrófilos/metabolismo , Fenotipo , Receptores de Antígenos de Linfocitos T/metabolismo , Estallido Respiratorio/genética , Streptococcus pneumoniae/patogenicidad , Zimosan/farmacología
18.
Science ; 260(5108): 679-82, 1993 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-8480178

RESUMEN

A recessive mutation was identified in a family of transgenic mice that resulted in a reversal of left-right polarity (situs inversus) in 100 percent of the homozygous transgenic mice tested. Sequences that flanked the transgenic integration site were cloned and mapped to mouse chromosome 4, between the Tsha and Hxb loci. During early embryonic development, the direction of postimplantation turning, one of the earliest manifestations of left-right asymmetry, was reversed in homozygous transgenic embryos. This insertional mutation identifies a gene that controls embryonic turning and visceral left-right polarity.


Asunto(s)
Desarrollo Embrionario y Fetal/genética , Genes Recesivos , Situs Inversus/genética , Alelos , Animales , Mapeo Cromosómico , Clonación Molecular , Femenino , Homocigoto , Masculino , Ratones , Ratones Transgénicos , Mutagénesis Insercional
19.
J Psychopharmacol ; 23(1): 40-50, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18515461

RESUMEN

Previous research has suggested that the separate aspects of executive functioning are differentially affected by ecstasy use. Although the inhibition process appears to be unaffected by ecstasy use, it is unclear whether this is true of heavy users under conditions of high demand. Tasks loading on the updating process have been shown to be adversely affected by ecstasy use. However, it remains unclear whether the deficits observed reflect the executive aspects of the tasks or whether they are domain general in nature affecting both verbal and visuo-spatial updating. Fourteen heavy ecstasy users (mean total lifetime use 1000 tablets), 39 light ecstasy users (mean total lifetime use 150 tablets) and 28 non-users were tested on tasks loading on the inhibition executive process (random letter generation) and the updating component process (letter updating, visuo-spatial updating and computation span). Heavy users were not impaired in random letter generation even under conditions designed to be more demanding. Ecstasy-related deficits were observed on all updating measures and were statistically significant for two of the three measures. Following controls for various aspects of cannabis use, statistically significant ecstasy-related deficits were obtained on all three updating measures. It was concluded that the inhibition process is unaffected by ecstasy use even among heavy users. By way of contrast, the updating process appears to be impaired in ecstasy users with the deficit apparently domain general in nature.


Asunto(s)
Trastornos Relacionados con Anfetaminas/fisiopatología , Cognición/efectos de los fármacos , Alucinógenos/toxicidad , N-Metil-3,4-metilenodioxianfetamina/toxicidad , Solución de Problemas/efectos de los fármacos , Adulto , Trastornos Relacionados con Anfetaminas/psicología , Cannabis/toxicidad , Cocaína/toxicidad , Femenino , Humanos , Dietilamida del Ácido Lisérgico/toxicidad , Masculino , Comprimidos
20.
AIDS Care ; 20(6): 733-40, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18576176

RESUMEN

Microbicides are a class of substances under development that could reduce the sexual transmission of HIV and other sexually transmitted diseases when applied locally to genital mucosal surfaces. Microbicide acceptability research has largely focused on product characteristics, rather than processes of negotiation within relationships about use. Gender relations, decision-making power and communication within sexual relationships are recognised as important determinants of condom and contraceptive use, and are likely to determine microbicide use also. As part of social science research linked to the Microbicides Development Programme (MDP) we combine relationship-based theories with anthropological work conducted with women and men using a placebo gel. We explore communication and decision-making in gel and condom use, including constructions of risk and trust. During the MDP301 Phase III pilot study, in-depth interviews were conducted at sites in South Africa, Tanzania, Uganda and Zambia. Following four weeks of placebo gel use, women and their partners were asked about gel use and acceptability, partner involvement, sexual practices and condom use. Data from 45 couples at five sites were analysed using a grounded theory approach in NVivo. Participation in the study did not require women to inform their partners, yet our data shows women seeking permission from their partners, negotiating disclosure, exchanging information and persuading or motivating for gel use. Although gel was supposedly 'woman-controlled', men exercised considerable influence in determining whether and how it was used. Despite this, negotiations around use were largely successful, since the gel increased sexual pleasure and provided opportunities for intimate communication and the building of trust. Decisions about condom and microbicide use are made in a dyadic context and involve a complex negotiation of risk and trust. Whilst preferences relating to product characteristics are largely individual, use itself is dependent on partnership dynamics and the broader social context in which sexual risk management occurs.


Asunto(s)
Antiinfecciosos/administración & dosificación , Condones/estadística & datos numéricos , Infecciones por VIH/prevención & control , Aceptación de la Atención de Salud/psicología , Parejas Sexuales/psicología , Administración Intravaginal , Adulto , Toma de Decisiones , Femenino , Humanos , Relaciones Interpersonales , Masculino , Factores de Riesgo , Conducta Sexual/psicología , Tanzanía , Uganda , Cremas, Espumas y Geles Vaginales/administración & dosificación , Zambia
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