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1.
HIV Med ; 21(9): 588-598, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32776431

RESUMEN

OBJECTIVES: We report the frequency of previous HIV testing at baseline in men who have sex with men (MSM) who enrolled in an HIV self-testing (HIVST) randomized controlled trial [an HIV self-testing public health intervention (SELPHI)]. METHODS: Criteria for enrolment were age ≥ 16 years, being a man (including trans men) who ever had anal intercourse (AI) with a man, not being known to be HIV positive and having consented to national HIV database linkage. Using online survey baseline data (2017-2018), we assessed associations with never having tested for HIV and not testing in the previous 6 months, among men who reported at least two recent condomless AI (CAI) partners. RESULTS: A total of 10 111 men were randomized; the median age was 33 years [interquartile range (IQR) 26-44 years], 89% were white, 20% were born outside the UK, 0.8% were trans men, 47% were degree educated, and 8% and 4% had ever used and were currently using pre-exposure prophylaxis (PrEP), respectively. In the previous 3 months, 89% reported AI and 72% reported CAI with at least one male partner. Overall, 17%, 33%, 54%, and 72% had tested for HIV in the last 3 months, 6 months, 12 months and 2 years, respectively; 13% had tested more than 2 years ago and 15% had never tested. Among 3972 men reporting at least two recent CAI partners, only 22% had tested in the previous 3 months. Region of residence and education level were independently associated with recent HIV testing. Among current PrEP users, 15% had not tested in the previous 6 months. CONCLUSIONS: Most men in SELPHI, particularly those reporting at least two CAI partners and current PrEP users, were not testing in line with current UK recommendations. The results of the trial will inform whether online promotion of HIVST addresses ongoing testing barriers.


Asunto(s)
Infecciones por VIH/diagnóstico , Prueba de VIH/métodos , Homosexualidad Masculina/estadística & datos numéricos , Profilaxis Pre-Exposición/estadística & datos numéricos , Conducta Sexual/clasificación , Adulto , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Masculino , Salud Pública , Autoevaluación , Conducta Sexual/estadística & datos numéricos , Parejas Sexuales , Reino Unido/epidemiología , Sexo Inseguro/estadística & datos numéricos
2.
HIV Med ; 21(3): 189-197, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31821698

RESUMEN

OBJECTIVES: SELPHI (HIV Self-Testing Public Health Intervention) is the largest randomized controlled trial (RCT) of HIV self-testing (HIVST) in a high-income setting to date, and has recruited 10 000 men who have sex with men (cis- and transgender) and transgender women who have sex with men. This qualitative substudy aimed to explore how those utilizing self-tests experience HIVST and the implications for further intervention development and scale-up. This is the first qualitative study in Europe investigating experiences of HIVST among intervention users, and the first globally examining the experience of using blood-based HIVST. METHODS: Thirty-seven cisgender MSM SELPHI participants from across England and Wales were purposively recruited to the substudy, in which semi-structured interviews were used to explore testing history, HIVST experiences and intervention preferences. Interviews were audio-recorded, transcribed and analysed through a framework analysis. RESULTS: Men accessed the intervention because HIVST reduced barriers related to convenience, stigma and privacy concerns. Emotional responses had direct links to acceptability. Supportive intervention components increased engagement with testing and addressed supportive concerns. HIVST facilitated more frequent testing, with the potential to reduce sexually transmitted infection (STI) screening frequency. Substudy participants with an HIV-positive result (n = 2) linked to care promptly and reported very high acceptability. Minor adverse outcomes (n = 2; relationship discord and fainting) did not reduce acceptability. Ease of use difficulties were with the lancet and the test processing stage. CONCLUSIONS: Intervention components shaped acceptability, particularly in relation to overcoming a perceived lack of support. The intervention was broadly acceptable and usable; participants expressed an unexpected degree of enthusiasm for HIVST, including those with HIV-positive results and individuals with minor adverse outcomes.


Asunto(s)
Detección Precoz del Cáncer/métodos , Infecciones por VIH/diagnóstico , Homosexualidad Masculina/estadística & datos numéricos , Personas Transgénero/estadística & datos numéricos , Adolescente , Adulto , Países Desarrollados , Inglaterra , Estudios de Evaluación como Asunto , Femenino , Humanos , Entrevistas como Asunto , Masculino , Aceptación de la Atención de Salud , Juego de Reactivos para Diagnóstico , Autoevaluación , Gales , Adulto Joven
3.
J Biol Chem ; 274(8): 5061-9, 1999 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-9988753

RESUMEN

Overexpression of the gene encoding the 70-kDa heat shock protein (hsp70) has previously been shown to protect neuronal cells against subsequent thermal or ischemic stress. It has no protective effect, however, against stimuli that induce apoptosis, although a mild heat shock (sufficient to induce hsp synthesis) does have a protective effect against apoptosis. We have prepared disabled herpes simplex virus-based vectors that are able to produce high level expression of individual hsps in infected neuronal cells without damaging effects. We have used these vectors to show that hsp27 and hsp56 (which have never previously been overexpressed in neuronal cells) as well as hsp70 can protect dorsal root ganglion neurons from thermal or ischemic stress. In contrast, only hsp27 can protect dorsal root ganglion neurons from apoptosis induced by nerve growth factor withdrawal, and hsp27 also protects the ND7 neuronal cell line from retinoic acid-induced apoptosis. However, hsp70 showed no protective effect against apoptosis in contrast to its anti-apoptotic effect in non-neuronal cell types. These results thus identify hsp27 as a novel neuroprotective factor and show that it can mediate this effect when delivered via a high efficiency viral vector.


Asunto(s)
Apoptosis/genética , Vectores Genéticos , Proteínas de Choque Térmico/genética , Neuronas/citología , Simplexvirus/genética , Animales , Línea Celular , Cricetinae , Ratas , Ratas Sprague-Dawley
4.
Eur J Neurosci ; 10(11): 3343-50, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9824447

RESUMEN

The heat shock proteins (HSPs) are induced by stressful stimuli and have a protective effect. Different HSPs protect with different efficiencies against different stresses indicating that optimal protection would be obtained with a non-stressful agent which induced a range of HSPs. We have prepared a herpesvirus vector expressing a constitutively active mutant form of heat shock factor 1 (HSF1) which, unlike the wild-type form of this transcription factor, does not require stress for its activation. Upon infection of neuronal cells, this virus induced a more restricted range of HSPs than in non-neuronal cells. Infection with the virus protected neuronal cells against subsequent thermal or ischaemic stress in accordance with its ability to induce HSP70 expression but did not protect them against apoptotic stimuli. The mechanisms of these effects and their significance for the use of HSF to manipulate HSP gene expression is discussed.


Asunto(s)
Apoptosis/fisiología , Proteínas de Unión al ADN/biosíntesis , Proteínas de Choque Térmico/biosíntesis , Calor/efectos adversos , Isquemia/patología , Neuronas/patología , Estrés Fisiológico/patología , Animales , Animales Recién Nacidos , Western Blotting , Línea Celular , Proteínas de Unión al ADN/genética , Vectores Genéticos , Factores de Transcripción del Choque Térmico , Técnicas In Vitro , Ratones , Mutación , Neuronas/metabolismo , Neuronas/virología , Ratas , Ratas Sprague-Dawley , Simplexvirus/genética , Raíces Nerviosas Espinales/patología , Factores de Transcripción
5.
Brain Res Mol Brain Res ; 42(2): 236-44, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9013779

RESUMEN

The induction of focal cerebral ischaemia in rats by middle cerebral artery occlusion has previously been shown to increase, over time, the mRNA levels of the heat shock proteins (HSPs) 27 and 70. However, the levels of HSP90 mRNA remain constant. In contrast, during global ischaemia, HSP70 and HSP90 mRNA levels are both raised, particularly in the CA1 neurons in the hippocampus, an area that is resistant to the insult in comparison to the surrounding regions. HSP27 mRNA is raised in the neuroglia in the subregions of the hippocampus. However, the protein levels of HSP27, 70 and 90 have not been characterised in focal ischaemia. With this data in mind, we have carried out a comparative study of HSP27, 56, 60, 70 and 90 mRNA and protein levels during focal cerebral ischaemia in rats, up to 24 h post-occlusion. We have shown that HSP70 and HSP27 mRNA levels are increased and also that HSP60 mRNA levels (which had also not previously been characterised in this model of focal ischaemia) are significantly raised. HSP90 and HSP56 mRNAs were not significantly elevated. On Western blot analysis, the inducible HSP72 protein was first detected at 8 h post-occlusion, HSP27 protein was detected only at 24 h post-occlusion and HSP60 protein, although constitutive, appeared to increase at 24 h post-occlusion. HSP56 protein levels appeared to rise on the occluded side, but HSP90 protein levels remained constant.


Asunto(s)
Isquemia Encefálica/metabolismo , Proteínas de Choque Térmico/metabolismo , Animales , Modelos Animales de Enfermedad , Inmunohistoquímica , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley
6.
J Cereb Blood Flow Metab ; 16(6): 1366-72, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8898713

RESUMEN

We have characterized the induction of the mitogen-inducible form of cyclo-oxygenase, COX-2, during focal cerebral ischemia following permanent middle cerebral artery occlusion (MCAO) in the rat. Marked unilateral induction of COX-2 mRNA was detected in ischemic regions ipsilateral to the occlusion. A significant increase in COX-2 mRNA was detected in "core" and "penumbra" regions of the cerebral cortex between 4 and 24 h after occlusion; this was most marked at 4 h in the penumbra region, in which a 19-fold increase above untreated control levels was detected. A smaller but significant induction was also detected at 4 h in the caudate. A correlation was demonstrated between the extent of COX-2 mRNA induction in cortical regions at 4 h and the severity of tissue damage subsequently detected at 24 h post MCAO. MK-801 significantly attenuated the induction of COX-2 mRNA in the penumbra region at 4 h. The demonstration of COX-2 induction following experimental ischemia highlights the importance of this reaction and its products and by-products, for example, free radicals, in the tissue response to this insult.


Asunto(s)
Isquemia Encefálica/enzimología , Isoenzimas/biosíntesis , Prostaglandina-Endoperóxido Sintasas/biosíntesis , ARN Mensajero/biosíntesis , Animales , Ciclooxigenasa 2 , Maleato de Dizocilpina/farmacología , Masculino , Fármacos Neuroprotectores/farmacología , ARN Mensajero/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
7.
J Neurochem ; 66(1): 6-13, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8522990

RESUMEN

We have characterised the induction of the mitogen-inducible form of cyclooxygenase, COX-2, in the rat cerebral cortex in response to excitotoxin injection into the nucleus basalis. This model is associated with intense stimulation of the ascending pathway to the cerebral cortex, seizure activity, and subsequent ipsilateral cortical induction of various immediate early genes (IEGs), including c-fos, c-jun, and zif268, and ornithine decarboxylase enzyme activity and mRNA, all of which processes are sensitive to treatment with the N-methyl-D-aspartate (NMDA) receptor antagonist MK-801. In this study we show that excitotoxin injection also causes a marked induction of COX-2 mRNA in ipsilateral cortex detectable at 1 h and peaking at 4 h, where COX-2 mRNA levels were 19 times those in unoperated animals. Levels of COX-2 mRNA remained significantly elevated at 24 h. The early induction of COX-2 at 1 h was also seen in sham-operated animals, but at 4 h the COX-2 mRNA level was significantly increased (4.4-fold) in animals injected with excitotoxin compared with sham-operated animals. The induction at this time point (4 h) was explored pharmacologically and found to be significantly attenuated by treatment with MK-801 (1.5 mg/kg), lamotrigine (10 mg/kg), which prevents presynaptic glutamate release by blocking voltage-sensitive Na+ channels, and the glucocorticoid dexamethasone (3 mg/kg), which has an indirect inhibitory effect on phospholipase A2 and COX activity.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Proteínas del Tejido Nervioso/biosíntesis , Fosfolipasas A/fisiología , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Sustancia Innominada/enzimología , Transmisión Sináptica/fisiología , Animales , Secuencia de Bases , Dexametasona/farmacología , Maleato de Dizocilpina/farmacología , Inducción Enzimática/efectos de los fármacos , Ácido Glutámico/metabolismo , Ácido Kaínico/farmacología , Lamotrigina , Masculino , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Fosfolipasas A/antagonistas & inhibidores , Fosfolipasas A2 , Prostaglandina-Endoperóxido Sintasas/genética , Proteínas Proto-Oncogénicas c-fos/fisiología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Secuencias Reguladoras de Ácidos Nucleicos , Sustancia Innominada/efectos de los fármacos , Triazinas/farmacología
8.
Neuropharmacology ; 34(5): 521-31, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7566487

RESUMEN

A number of conditions associated with persistent excitation such as electrically and chemically-induced seizures cause a rapid increase in the expression of immediate early genes (IEG) such as c-fos. In this study the time-course of induction of c-jun, jun-B and zif 268 mRNA by kainate was characterized in rat cerebral cortex and compared to that of c-fos mRNA induction. Unilateral injection of kainate into the nucleus basalis caused a significant induction of c-jun mRNA in cerebral cortex from 4 hr which was maximal at 8 hr, being 3 times greater in ipsilateral cortex than in control cortex. This pattern was also shown for jun-B and was similar, but of small magnitude, to that obtained with c-fos mRNA, with a maximal increase at 8 hr, whilst the maximal induction of zif-268 mRNA preceded these responses occurring at 4 hr. A marked difference was seen in duration in the c-jun induction which was maintained at a high level for at least 24 hr. Treatment of animals with MK-801 (within 30 min of injection of kainate) or dexamethasone (2-30 mg/kg) at the time of kainate injection significantly attenuated the response. The induction of c-fos mRNA by kainate injection was most sensitive to dexamethasone (2 mg/kg), whereas a higher dose (30 mg/kg) was required to attenuate the induction of zif-268 mRNA. These results show that a time-dependent and co-ordinated induction of c-fos, c-jun, jun-B and zif-268 mRNA in cerebral cortex occurs in response to the persistent excitation caused by excitotoxin injection which is mediated by glutamate and shows a differential sensitivity to dexamethasone.


Asunto(s)
Corteza Cerebral/efectos de los fármacos , Dexametasona/farmacología , Maleato de Dizocilpina/farmacología , Genes Inmediatos-Precoces/genética , Animales , Expresión Génica , Masculino , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Proteínas Proto-Oncogénicas c-jun/biosíntesis , ARN Mensajero/biosíntesis , Ratas , Ratas Endogámicas , Factores de Tiempo
9.
Stroke ; 25(9): 1855-60; discussion 1861, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8073469

RESUMEN

BACKGROUND AND PURPOSE: There is strong evidence to implicate glutamate in the cerebral damage caused by ischemia. In this study we investigated the role of glutamate receptors in mediating effects of middle cerebral artery occlusion (MCAO) on immediate early gene expression in the rat by quantitation of mRNA levels. METHODS: The effect of MCAO on the induction of immediate early genes was studied in five regions, both ipsilateral and contralateral to the occlusion: the "core" ischemic area of the cortex in the central region of the middle cerebral artery territory, the surrounding area, frontal cortex, occipital cortex, and hippocampus. Levels of c-fos, c-jun, zif-268, and krox-20 mRNA were measured by Northern and slot blot analysis. RESULTS: A large induction of c-fos mRNA was obtained in all four cortical regions ipsilateral to the occlusion, with the greatest effect detected in the core area. Little effect was detected in the ipsilateral hippocampus and in all contralateral regions. Pretreatment with MK-801 (3 mg/kg) largely inhibited the induction of c-fos mRNA, indicating that the induction was mediated through an N-methyl-D-aspartate subtype of glutamate receptor. MCAO also produced a significant induction of c-jun and zif-268 mRNA in ipsilateral cortical regions. CONCLUSIONS: These results indicate that MCAO causes a profound modulation of the expression of multiple genes in an extensive area of cerebral cortex extending beyond the immediate area supplied by the middle cerebral artery. The marked effect of MK-801 indicates the potential importance of glutamate antagonists in restricting the widespread deleterious effects of glutamate.


Asunto(s)
Encéfalo/metabolismo , Maleato de Dizocilpina/farmacología , Expresión Génica/fisiología , Genes Inmediatos-Precoces/fisiología , Ataque Isquémico Transitorio/metabolismo , Animales , Presión Sanguínea/efectos de los fármacos , Encéfalo/efectos de los fármacos , Lateralidad Funcional , Expresión Génica/efectos de los fármacos , Genes Inmediatos-Precoces/efectos de los fármacos , Genes fos/efectos de los fármacos , Genes jun/efectos de los fármacos , Ataque Isquémico Transitorio/fisiopatología , Masculino , Especificidad de Órganos , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Proteínas Proto-Oncogénicas c-jun/biosíntesis , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Tubulina (Proteína)/biosíntesis
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