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1.
Appl Microbiol Biotechnol ; 104(1): 131-144, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31781817

RESUMEN

The availability of bioresources is a precondition for life science research, medical applications, and diagnostics, but requires a dedicated quality management to guarantee reliable and safe storage. Anecdotal reports of bacterial isolates and sample contamination indicate that organisms may persist in liquid nitrogen (LN) storage tanks. To evaluate the safety status of cryocollections, we systematically screened organisms in the LN phase and in ice layers covering inner surfaces of storage tanks maintained in different biobanking facilities. We applied a culture-independent approach combining cell detection by epifluorescence microscopy with the amplification of group-specific marker genes and high-throughput sequencing of bacterial ribosomal genes. In the LN phase, neither cells nor bacterial 16S rRNA gene copy numbers were detectable (detection limit, 102 cells per ml, 103 gene copies per ml). In several cases, small numbers of bacteria of up to 104 cells per ml and up to 106 gene copies per ml, as well as Mycoplasma, or fungi were detected in the ice phase formed underneath the lids or accumulated at the bottom. The bacteria most likely originated from the stored materials themselves (Elizabethingia, Janthibacterium), the technical environment (Pseudomonas, Acinetobacter, Methylobacterium), or the human microbiome (Bacteroides, Streptococcus, Staphylococcus). In single cases, bacteria, Mycoplasma, fungi, and human cells were detected in the debris at the bottom of the storage tanks. In conclusion, the limited microbial load of the ice phase and in the debris of storage tanks can be effectively avoided by minimizing ice formation and by employing hermetically sealed sample containers.


Asunto(s)
Bancos de Muestras Biológicas/normas , Criopreservación/instrumentación , Contaminación de Equipos , Nitrógeno , Bacterias/genética , Carga Bacteriana , ADN Bacteriano/genética , Hongos/genética , Humanos , Hielo , Límite de Detección , ARN Ribosómico 16S
2.
Gesundheitswesen ; 75(7): 405-12, 2013 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-22864846

RESUMEN

BACKGROUND: Telemedicine-enabled stroke networks increase the probability of a good clinical outcome. There is a shortage of evidence about the effects of this new approach on costs for inpatient care and nursing care. METHODS: We analysed health insurance and nursing care fund data of a statutory health insurance company (AOK Bayern). Data from stroke patients initially treated in a TeleStroke network (TEMPiS - telemedical project for integrative stroke care) between community hospitals and academic stroke centres were compared to data of matched hospitals without specialised stroke care and telemedical support. Costs for nursing care were obtained over a 30-month period after the initial stroke. To rule out pre-existing differences between network and control hospitals, costs of stroke care were also analysed during a time period before network implementation. FINDINGS: 1 277 patients (767 in intervention, 510 in control hospitals) were analysed in the post-implementation period. An increased proportion of patients treated in intervention hospitals had a favourable outcome concerning the level of required nursing care. Patients in intervention hospitals had higher costs for acute inpatient care (5 309 € vs. 4 901 €, p=0.04), but lower nursing care fund costs (3 946 € vs. 5 132 €; p=0.04). There was no difference in relation to absolute total costs obtained in the post-implementation period. However, nursing care costs per survived year were significantly lower in intervention hospitals (1 953 € vs. 2 635 €; p=0.005). No significant differences were found in the pre-implementation period. CONCLUSIONS: Considering both health insurance and nursing care fund costs, the incremental costs for TeleStroke network care in hospitals are compensated by savings in outpatient care.


Asunto(s)
Economía de la Enfermería/estadística & datos numéricos , Costos de la Atención en Salud/estadística & datos numéricos , Hospitalización/economía , Atención de Enfermería/estadística & datos numéricos , Accidente Cerebrovascular/economía , Accidente Cerebrovascular/enfermería , Telemedicina/economía , Anciano , Análisis Costo-Beneficio , Femenino , Alemania/epidemiología , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Modelos Económicos , Prevalencia , Medición de Riesgo , Accidente Cerebrovascular/epidemiología , Telemedicina/estadística & datos numéricos
4.
Nervenarzt ; 80(2): 184-9, 2009 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-19194685

RESUMEN

BACKGROUND: Telemedicine is increasingly used for acute stroke care, making neurological expertise available in nonspecialized hospitals. There are few data about telemedicine's acceptance by either medical staff or patients at treating hospitals. METHODS: Telemedicine's acceptance was evaluated in the Telemedical Project for Integrative Stroke Care (TEMPIS), a network of two stroke centers and 12 community hospitals in the German state of Bavaria; the grading of teleconsultation regarding video and audio quality, time consumption, and medical relevance was assessed in two periods, 2004 and 2007. Overall satisfaction with in-hospital treatment was compared between patients in telemedically-linked hospitals with specialized stroke care and patients treated in conventional community hospitals. With regard to sufficient follow-up rates, ratings were restricted to patients living at home without severe disability at 3 months after stroke. A second evaluation analyzed how the parameter "Telemedical assessment of patient" (36% of patients in TEMPIS hospitals) affected overall satisfaction. RESULTS: Respectively, 140 and 127 uses of telemedicine were assessed in the two evaluation periods. Video quality, time consumption, and medical relevance were graded "excellent" by over 50% in both periods. Audio quality was rated "excellent" by only 22% in the first period but 69% in the second. Excellent overall satisfaction was expressed significantly more frequently by patients at TEMPIS hospitals (total number 1044) than by those at control hospitals (total number 484; 56% vs 47% respectively, P<0.01). Patient consultation via telemedicine per se did not correlate with modified grading. CONCLUSIONS: Acceptance of telemedicine in acute stroke care was high and stable over a long period. This study suggests improved overall satisfaction with treatment in hospitals offering specialized care and linked via telemedicine. Clinical assessment via telemedicine had no major effect on satisfaction.


Asunto(s)
Actitud del Personal de Salud , Aceptación de la Atención de Salud/estadística & datos numéricos , Satisfacción del Paciente/estadística & datos numéricos , Garantía de la Calidad de Atención de Salud , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Telemedicina/estadística & datos numéricos , Alemania , Humanos , Accidente Cerebrovascular/epidemiología
6.
Dtsch Med Wochenschr ; 131(23): 1309-14, 2006 Jun 09.
Artículo en Alemán | MEDLINE | ID: mdl-16761199

RESUMEN

BACKGROUND: Although treatment in a stroke unit has been proven to be effective, most stroke patients in rural areas have no access to it. The community hospital of Ebersberg (Bavaria/Germany) joined the Telemedic Project for Integrative Stroke Care (TEMPiS) in order to optimize the quality of stroke care. This analysis focuses on changes in stroke management using generally accepted indicators for quality of acute stroke treatment. METHODS: The core elements consisted of the setting up of a stroke ward in the community hospital, continual stroke education and a 24-hour telemedical consultation service offered by stroke centers. Treatment of stroke patients was documented during two 12-months periods before the project was started start (i.e. retrospectively) and during the course of the project (prospectively). In addition, data on fatal outcome and institutionalization of patients who had lived at home before the qualifying event were collected 12 months after stroke onset. RESULTS: There were 299 admissions for stroke or transient ischemic attacks between 1 Nov 2001 and 31 Oct 2002, and 305 between 7 July 2003 and 6 June 2004. Length of in-hospital stay decreased from 12.1 to 9.2 days. More patients (10.3 vs. 1.3%) were transferred to other acute hospitals during the later period. Indicators for stroke care quality improved: numbers of cerebral imaging rose from 56.5% to 96.4%, of duplex sonography of cervical arteries from 43.5 to 72.8 %, of speech therapy from 0% to 50.8% and of occupational therapy from 0 to 33.4%. One year after admission, 18.9% and 17.2%, respectively, of the patients had died, while 10.2% and 6.1% were living in institutions. CONCLUSION: Participation in the TEMPiS network substantially improved stroke care quality according to national and international guidelines. These improvements may lead to a better prognosis after a stroke.


Asunto(s)
Redes de Comunicación de Computadores/normas , Departamentos de Hospitales/normas , Ataque Isquémico Transitorio/terapia , Indicadores de Calidad de la Atención de Salud/normas , Consulta Remota/normas , Accidente Cerebrovascular/terapia , Prestación Integrada de Atención de Salud/normas , Femenino , Alemania , Hospitales Comunitarios/normas , Humanos , Ataque Isquémico Transitorio/mortalidad , Tiempo de Internación/estadística & datos numéricos , Masculino , Evaluación de Procesos y Resultados en Atención de Salud/estadística & datos numéricos , Proyectos Piloto , Garantía de la Calidad de Atención de Salud/normas , Estudios Retrospectivos , Accidente Cerebrovascular/mortalidad
7.
Dtsch Med Wochenschr ; 130(44): 2495-500, 2005 Nov 04.
Artículo en Alemán | MEDLINE | ID: mdl-16252208

RESUMEN

BACKGROUND: Specific stroke subtypes like subarachnoid hemorrhages or malignant brain infarcts require immediate interventions, but treatment options are offered mainly in specialized centers. For this reason, interhospital transfers from primary hospitals need to be done without delay. METHODS: The telemedic pilot project for integrative stroke care (TEMPiS) connects 2 stroke centers and 12 regional hospitals in Bavaria (Germany). Core elements are the implementation of stroke wards, telemedic consultation and improvement of emergency interhospital transfers. Organization of patient transports is offered by the central telemedic service. During the first 12 months of the continuing project all interhospital transfers initiated by the central telemedic service were prospectively documented. Emergency transports were analysed according to diagnosis, type of transport, distance and time delays. RESULTS: A total of 252 interhospital transfers were recommended in teleconsultations; finally 221 transports took place. Median total duration of transfers (including the necessary arrangements) was 134 min (interquartile range: 105-219) for intracerebral hemorrhages (N = 58), 138 min (95-157) for subarachnoid hemorrhages (N = 31), 161 min (100-230) for malignant infarcts (N = 22) and 147 min (109-180) for suspected basilar artery occlusion (N = 28). Time from admission in the primary hospital to initiation of interhospital transfer was 135 min (median; interquartile range: 86-172), transport time was 81 min (60-116). Helicopter transport did not save time for transfer distances up to 50 kilometres, compared to transport via ambulance (including assistance of hospital physicians). Transport using a special intensive care vehicle was much more time consuming because of the longer transport preparation time. CONCLUSION: Emergency transfers of stroke patients are time consuming. This may contribute to additional harm being done to severely ill patients. Faster organization and conduct of transports is required.


Asunto(s)
Infarto Encefálico/terapia , Transferencia de Pacientes/normas , Programas Médicos Regionales/normas , Consulta Remota , Hemorragia Subaracnoidea/terapia , Urgencias Médicas , Alemania , Hospitales Especializados/normas , Hospitales Especializados/estadística & datos numéricos , Humanos , Transferencia de Pacientes/organización & administración , Transferencia de Pacientes/estadística & datos numéricos , Proyectos Piloto , Programas Médicos Regionales/organización & administración , Factores de Tiempo , Transporte de Pacientes/métodos , Transporte de Pacientes/normas , Transporte de Pacientes/estadística & datos numéricos
8.
Neurocrit Care ; 3(1): 27-32, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16159092

RESUMEN

BACKGROUND: The benefit of tissue plasminogen activator (t-PA) is strongly associated with the time to treatment. In Bavaria, Germany, only half of the population has the opportunity to be transferred to 1 of the 19 stroke units within the critical time window of less than 3 hours. The aim of this study was to investigate the benefit of a new stroke-code-box for t-PA thrombolysis combined with a telemedicine network system to increase the use of acute stroke thrombolysis. METHODS: Two specialized stroke centers in Germany established a 24-hour telemedicine network (Telemedicine Pilot Project of an Integrated Stroke Care [TEMPiS]) to advise 12 community hospitals in eastern Bavaria. These clinics are linked via telemedicine in a 24-hour/7-day service network that allows patients to be examined by experts via a videoconference system Additionally, a special stroke-code-box for acute t-PA thrombolysis was designed to reduce time in the application and documentation process. RESULTS: In the 12-month period before implementation of the TEMPiS network system, 10 patients had received systemic thrombolysis. In our 6-month study period (from July to December 2003) and after implementation of a stroke-code-box for t-PA thrombolysis within the telestroke network, 164 patients with acute stroke were presented with t-PA treatment indications. Of this patient population, 27.4% (45 of 164) received t-PA. CONCLUSIONS: Stroke care, including t-PA thrombolysis in non-urban areas, is feasible using a modern stroke unit concept within a telestroke network. With the expertise of specialized stroke centers accessed via telemedicine and the design of a stroke-code-box for t-PA thrombolysis, nearly one-third of patients presented with a possible indication for systemic thrombolysis can be treated with t-PA, thereby increasing the options for a successful stroke treatment.


Asunto(s)
Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Telemedicina/métodos , Activador de Tejido Plasminógeno/uso terapéutico , Anciano , DC-I , Femenino , Lateralidad Funcional , Hospitales Comunitarios , Humanos , Masculino , Persona de Mediana Edad , Población Rural , Accidente Cerebrovascular/clasificación , Factores de Tiempo , Resultado del Tratamiento
9.
Vet Q ; 27(1): 21-9, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15835281

RESUMEN

Quality management on dairy farms becomes more and more important regarding the different areas of animal health, animal welfare and food safety. Monitoring animals, farm conditions and farm records can be extended with risk identification and risk management. The hazard analysis critical control point's system is useful as an on farm strategy to control the product as well as the production process on the areas of animal health, animal welfare and food safety. This article deals in detail with the question how to develop a qualitative method where risk can be defined as an interaction between probability and impact. Two parts of the production process (milk harvest and treatment of cows) where used as an example how to apply the hazard analysis critical control point's system on chemical, physical and microbiological contaminants of milk. Not just only by summarizing the different critical checkpoints for each area but also by giving them a precise judgement of probability and impact.


Asunto(s)
Seguridad de Productos para el Consumidor , Industria Lechera/normas , Contaminación de Alimentos/prevención & control , Manipulación de Alimentos/normas , Inspección de Alimentos/métodos , Leche , Animales , Productos Lácteos/análisis , Productos Lácteos/microbiología , Productos Lácteos/normas , Industria Lechera/métodos , Contaminación de Alimentos/análisis , Manipulación de Alimentos/métodos , Inspección de Alimentos/normas , Humanos , Leche/química , Leche/microbiología , Leche/normas , Control de Calidad , Medición de Riesgo , Gestión de Riesgos
10.
Nervenarzt ; 75(2): 161-5, 2004 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-14770288

RESUMEN

More than 100 stroke units have been established in Germany. In rural areas, however, acute stroke care needs to be improved. In order to advance clinical stroke therapy, two specialized stroke centers founded a telemedicine network (TEMPiS) among 12 community hospitals in eastern Bavaria. Each network hospital established specialized stroke wards where qualified teams manage acute stroke patients. Twenty-four hours daily, physicians in local hospitals are able to contact the stroke centers via videoconferencing including transmission of digital DICOM data. To study the efficacy of this network, a controlled trial will be performed. Five TEMPiS-network hospitals will be matched with five other hospitals equal in size, catchment area, and diagnostic techniques. For about 1 year, all consecutive stroke cases in the matched study hospitals will be prospectively recorded in a database. Neurological deficits will be quantified on the National Institute of Health Stroke Scale within 24 h after stroke onset. Mortality and institutional care as a combined primary endpoint will be assessed after 3 and 12 months. Furthermore, functional outcome according to the modified Rankin scale, Barthel score, and quality of life will be assessed using a standard telephone interview. Data acquisition started in July 2003, and final results are expected in 2005.


Asunto(s)
Redes de Comunicación de Computadores , Eficiencia Organizacional , Departamentos de Hospitales , Sistemas de Información en Hospital , Sistemas Integrados y Avanzados de Gestión de la Información , Garantía de la Calidad de Atención de Salud , Accidente Cerebrovascular/terapia , Telemedicina , Servicios Centralizados de Hospital , Evaluación de la Discapacidad , Estudios de Seguimiento , Alemania , Hospitales Comunitarios , Humanos , Grupo de Atención al Paciente , Calidad de Vida , Consulta Remota , Accidente Cerebrovascular/mortalidad , Análisis de Supervivencia
11.
J Neurol ; 250(3): 320-4, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12638023

RESUMEN

BACKGROUND: Systemic thrombolysis with tissue plasminogen activator (t-PA) for treatment of acute ischemic stroke was approved in Germany in 2000. Up to now, only data from single centers have been available for the study of the use of thrombolysis in a hospital-based approach outside controlled trials. We therefore sought to determine the frequency of application and complications as well as the patient outcome after t-PA treatment in clinical routine of specialized stroke centers in Germany. METHODS: Within the German Stroke Data Bank Collaboration, 6234 consecutive patients with ischemic stroke were prospectively documented in 20 stroke centers between 1998 and 1999. The patients were centrally followed via telephone interview after 3 months and 1 year to assess global functional outcome using the Modified Rankin Scale. RESULTS: 250 patients (4 %) received systemic t-PA treatment during the study period. The baseline characteristics of these patients were comparable to large clinical trials and phase IV studies. Symptomatic and asymptomatic parenchymal hemorrhage occurred in 22 patients (8.8 %) and was fatal in 3 patients. Follow-up data after 3 months were obtained in 82.4 % of all patients, of which 35 % had a favorable functional outcome (mRS /= 4) and 17 % had died. CONCLUSION: The results of our study agree with the assumption that thrombolytic therapy can be performed safely and effectively in daily clinical practice. Nevertheless, the small proportion of patients receiving thrombolysis even in specialized stroke centers calls for further improvement of acute stroke management in Germany.


Asunto(s)
Fibrinolíticos/administración & dosificación , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica/estadística & datos numéricos , Activador de Tejido Plasminógeno/administración & dosificación , Hemorragia Cerebral/patología , Femenino , Fibrinolíticos/efectos adversos , Estudios de Seguimiento , Alemania , Humanos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/mortalidad , Factores de Tiempo , Activador de Tejido Plasminógeno/efectos adversos , Resultado del Tratamiento
12.
Cell Death Differ ; 8(7): 679-86, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11464212

RESUMEN

Stroke is the third most common cause of death in the Western world. The mechanisms of brain damage in the affected areas are largely unknown. Hence, rational treatment strategies are limited. Previous experimental evidence suggested that cerebral lesions were less prominent in CD95 (APO-1/Fas)-deficient (lpr) than in wild-type mice. Additional results strongly suggested that the CD95-ligand (CD95L) was a major cause of neuronal autocrine suicide in the penumbra. These data and the assumption that death-receptor systems might determine stroke-related damage in the brain prompted us to examine these systems in in vitro and in vivo models of ischemia. We showed that hybrids of TNF-deficient and gld mice were strongly resistant towards stroke-induced damage. To determine the mechanism of action of TNF and CD95L, we separately investigated their influence on primary ischemic death and secondary inflammatory injury. Inhibition of both TNF and CD95L in vitro prevented death of primary neurons induced by oxygen-glucose deprivation and reperfusion. The recruitment of inflammatory cells to the ischemic hemisphere was abrogated in the absence of both TNF and CD95L. Significantly, mice injected with a mixture of neutralizing anti-TNF and anti-CD95L antibodies 30 min after induction of stroke showed a marked decrease in both infarct volumes and mortality. Accordingly, the locomotor performance of these animals was not significantly impaired in comparison to sham-operated animals. These data reveal that inhibition of TNF and CD95L blocks stroke-related damage at two levels, the primary ischemic and the secondary inflammatory injury. These results offer new approaches in stroke treatment.


Asunto(s)
Glicoproteínas de Membrana/antagonistas & inhibidores , Glicoproteínas de Membrana/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/patología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Anticuerpos/inmunología , Anticuerpos/farmacología , Anticuerpos/uso terapéutico , Apoptosis/efectos de los fármacos , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Células Cultivadas , Modelos Animales de Enfermedad , Proteína Ligando Fas , Inmunohistoquímica , Inflamación/metabolismo , Inflamación/patología , Glicoproteínas de Membrana/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Accidente Cerebrovascular/metabolismo , Factor de Necrosis Tumoral alfa/inmunología
13.
Mech Dev ; 104(1-2): 89-98, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11404083

RESUMEN

At weaning, milk producing mammary epithelial cells undergo apoptosis and are removed by phagocytosis. Here, we show that mouse mammary gland involution is associated with mitochondrial cytochrome c release and processing of numerous caspases, including caspase-1, -3, -7, -8 and -9. Induction of caspase-3-like activity paralleled cleavage of poly-(ADP--ribose) polymerase. Dexamethasone inhibited processing of caspase-3, -7 and -8 and apoptosis, but had no effect on caspase-1 accumulation and cytochrome c release. In Bcl-2 transgenic animals, cytochrome c release, caspase activation and apoptosis were impaired. Thus, the pro-apoptotic signaling pathway in mammary epithelial cells during involution involves the release of cytochrome c and activation of caspases. It is inhibited by Bcl-2 at the mitochondrial level and by dexamethasone at a post-mitochondrial level.


Asunto(s)
Caspasas/metabolismo , Grupo Citocromo c/metabolismo , Glándulas Mamarias Animales/fisiología , Destete , Animales , Apoptosis , Western Blotting , Caspasa 1/metabolismo , Caspasa 3 , Caspasa 7 , Caspasa 8 , Caspasa 9 , Dexametasona/farmacología , Activación Enzimática , Glucocorticoides/farmacología , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fagocitosis , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal , Espectrometría de Fluorescencia , Factores de Tiempo
14.
Circulation ; 102(8): 915-20, 2000 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-10952962

RESUMEN

BACKGROUND: The death of cardiac cells during ischemia and reperfusion is partially mediated by apoptosis, as seen, eg, in autopsy material of patients after acute myocardial infarction. METHODS AND RESULTS: To study the role of CD95/Fas/Apo1 for induction of postischemic cell death, we used an ischemia/reperfusion model of isolated rat and mouse hearts in Langendorff perfusion. In this model, caspase-dependent apoptosis occurred during postischemic reperfusion. Moreover, soluble CD95 ligand/Fas ligand was released by the postischemic hearts early after the onset of reperfusion. In addition, this ligand was synthesized de novo under these circumstances. Similar findings were observed for other "death-inducing" ligands, such as tumor necrosis factor (TNF)-alpha and TNF-related apoptosis-inducing ligand. In primary adult rat myocyte culture, hypoxia and reoxygenation caused a marked increase in sensitivity to the apoptotic effects of CD95 ligand. Isolated hearts from mice lacking functional CD95 (lpr) display marked reduction in cell death after ischemia and reperfusion compared with wild-type controls. CONCLUSIONS: These data suggest that CD95/Apo1/Fas is directly involved in cell death after myocardial ischemia. The CD95 system might thus represent a novel target for therapeutic prevention of postischemic cell death in the heart.


Asunto(s)
Apoptosis/fisiología , Isquemia Miocárdica/patología , Miocardio/patología , Receptor fas/fisiología , Clorometilcetonas de Aminoácidos/farmacología , Animales , Proteínas Reguladoras de la Apoptosis , Inhibidores de Caspasas , Caspasas/fisiología , Muerte Celular/fisiología , Células Cultivadas , Inhibidores de Cisteína Proteinasa/farmacología , Proteína Ligando Fas , Corazón/fisiología , Técnicas In Vitro , Masculino , Glicoproteínas de Membrana/biosíntesis , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Isquemia Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Miocardio/citología , Miocardio/metabolismo , Ratas , Ratas Wistar , Solubilidad , Ligando Inductor de Apoptosis Relacionado con TNF , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/metabolismo
15.
Neuroscience ; 95(3): 753-62, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10670442

RESUMEN

The immunophilin ligand FK506 (Tacrolimus) is used for prevention of graft rejection following organ transplantation. FK506 is a high-affinity ligand for FK506-binding proteins, an immunophilin subgroup of peptidyl-prolyl-cis/trans-rotamases abundant in the mammalian brain. Here, we demonstrate that FK506 is a potent survival factor that prevents neuronal cell death following axotomy of central intrinsic neurons. Administration of FK506 (2 mg/kg, s.c., per day for two days pre-axotomy and for up to eight days post-axotomy) effectively delayed and reduced the death of axotomized neurons in the substantia nigra pars compacta following transection of the medial forebrain bundle. In saline-treated controls, 75%, 89% and 92% of nigral neurons died after 25, 50 and 60 days post-axotomy, respectively. In contrast, application of FK506 resulted in survival of 46%, 44% and 28% of the axotomized nigral neurons, and the majority of these surviving neurons showed continuous expression of tyrosine hydroxylase, the pacemaker enzyme for dopamine synthesis. Moreover, FK506 significantly reduced the expression of the inducible transcription factor c-Jun and its N-terminal phosphorylation and prevented the axotomy-induced suppression of the constitutive transcription factor ATF-2 in neurons of the substantia nigra and mammillary body. The latter is also axotomized by the coincident transection of the mammillothalamic tract, but the mammillary neurons survive the axotomy. In contradistinction to FK506, the non-immunosuppressive FK506-binding protein ligand GPI-1046 (25 or 12.5 mg/kg, applied once or twice per day for two days pre-axotomy and for eight days post-axotomy) was completely ineffective for all these parameters investigated. Finally, FK506, but not GPI-1046, impressively accelerated the recovery from surgery. Our data provide the first evidence that FK506 acts as a neuroprotective molecule that rescues axotomized otherwise degenerating central intrinsic neurons in the adult mammalian brain by mechanisms that interfere with the transcriptional program of the axotomy-induced cell body response, such as activating transcription factor-2 suppression and c-Jun expression and phosphorylation.


Asunto(s)
Inmunofilinas/metabolismo , Haz Prosencefálico Medial/fisiología , Fármacos Neuroprotectores/farmacología , Proteínas Proto-Oncogénicas c-jun/antagonistas & inhibidores , Pirrolidinas/farmacología , Sustancia Negra/metabolismo , Tacrolimus/farmacología , Animales , Muerte Celular/efectos de los fármacos , Desnervación , Ligandos , Masculino , Ratas , Ratas Sprague-Dawley
16.
Eur J Neurosci ; 12(1): 27-32, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10651857

RESUMEN

Startle disease or hereditary hyperekplexia has been shown to result from mutations in the alpha1-subunit gene of the inhibitory glycine receptor (GlyR). In hyperekplexia patients, neuromotor symptoms generally become apparent at birth, improve with age, and often disappear in adulthood. Loss-of-function mutations of GlyR alpha or beta-subunits in mice show rather severe neuromotor phenotypes. Here, we generated mutant mice with a transient neuromotor deficiency by introducing a GlyR beta transgene into the spastic mouse (spa/spa), a recessive mutant carrying a transposon insertion within the GlyR beta-subunit gene. In spa/spa TG456 mice, one of three strains generated with this construct, which expressed very low levels of GlyR beta transgene-dependent mRNA and protein, the spastic phenotype was found to depend upon the transgene copy number. Notably, mice carrying two copies of the transgene showed an age-dependent sensitivity to tremor induction, which peaked at approximately 3-4 weeks postnatally. This closely resembles the development of symptoms in human hyperekplexia patients, where motor coordination significantly improves after adolescence. The spa/spa TG456 line thus may serve as an animal model of human startle disease.


Asunto(s)
Receptores de Glicina/genética , Receptores de Glicina/metabolismo , Reflejo de Sobresalto/genética , Médula Espinal/metabolismo , Temblor/genética , Animales , Membrana Celular/metabolismo , Cruzamientos Genéticos , Femenino , Genotipo , Homocigoto , Humanos , Hipercinesia/genética , Masculino , Ratones , Ratones Transgénicos , Fenotipo , ARN Mensajero/genética , Ratas , Transcripción Genética , Temblor/fisiopatología
17.
J Eur Acad Dermatol Venereol ; 13(1): 28-35, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10565627

RESUMEN

OBJECTIVE: To study the effects of proteolytic enzymes on mice hair follicles, particularly on cells of the bulge area regarded as follicle stem cells. BACKGROUND: Previous application by iontophoresis of proteolytic enzymes on guinea pig skin resulted in degenerative effects on hair follicles and the hypothesis was proposed that some of the affected cells could be stem cells. METHODS: To mark putative stem cells transgenic mice were produced carrying the lac-Z gene fused to the Upstream Regulatory Region (URR) of Human Papilloma Virus 11 (HPV11), as they express this gene specifically in the cells of the bulge area. Chymotrypsin and papain were applied on skin by iontophoresis, trypsin in the form of liposomes. RESULTS: Enzyme application, both by electrophoresis and as liposomes, led to intense degenerative effects of the hair follicle, such as detachment of the inner root sheath, cystic dilation of the hair shaft and presence of epithelial cells within the lumen. Some of these cells represent hair follicle stem cells expressing beta-galactosidase (beta-gal), having been detached from the bulge area as a result of enzyme treatment, implying impairment of their function.


Asunto(s)
Quimotripsina/administración & dosificación , Folículo Piloso/efectos de los fármacos , Folículo Piloso/patología , Papaína/administración & dosificación , beta-Galactosidasa/efectos de los fármacos , Animales , Portadores de Fármacos , Femenino , Iontoforesis , Liposomas , Ratones , Ratones Transgénicos , Valores de Referencia , beta-Galactosidasa/biosíntesis
18.
J Invest Dermatol ; 112(6): 893-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10383735

RESUMEN

We have generated transgenic mice carrying the URR of the human papillomavirus type 11 ligated in front of the Escherichia coli beta-galactosidase coding region sequence. Using X-Gal staining to demonstrate beta-galactosidase production, we observed a hair-specific transcription of the reporter gene. This transcription was limited to the epithelial cells of the hair bulge region. The transgene was developmentally regulated, as no LacZ staining was demonstrated during embryogenesis and specific staining was first observed after birth. Surprisingly, dexamethasone and ultraviolet B, but not phorbol myristate acetate or progesterone treatment of the animals resulted in an increase in number and intensity of hair follicles expressing the reporter gene.


Asunto(s)
Papillomaviridae/genética , Animales , Dexametasona/farmacología , Células Epiteliales/virología , Femenino , Secciones por Congelación , Expresión Génica , Genes Reporteros/genética , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Transgénicos , Regiones Promotoras Genéticas , Factor de Transcripción AP-1/genética , Transfección , Transgenes/efectos de los fármacos , Transgenes/genética , beta-Galactosidasa/análisis
19.
Brain Res ; 826(2): 210-9, 1999 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-10224298

RESUMEN

Ceramide is a key mediator of apoptosis during the cellular stress response which is also involved in stroke-induced death. Transient occlusion of the middle cerebral artery (MCA) in rats led to a strong generation of ceramide as measured in thalamus and entorhinal cortex of the ischemic brain tissue. Enhanced levels of ceramide may be involved in apoptosis signaling following stroke since exogenously added synthetic C2-ceramide increased expression of c-jun and the death-inducing ligands (DILs) CD95-L, TRAIL and TNF-alpha in neuroblastoma cells. DILs in turn mediated death via binding to their respective receptors as concluded from diminished apoptosis upon blocking of the common pathway by dominant negative FADD. C2-ceramide induced both necrosis and apoptosis in a concentration-dependent manner corresponding to the situation present in the ischemic brain. The immunosuppressant FK506 inhibited the release of ceramide, expression of CD95-L and apoptosis in an in vitro and in vivo model for ischemia/reperfusion. These data suggest that ceramide is a crucial initiator of death, e.g., by induction of DILs following stroke.


Asunto(s)
Apoptosis/efectos de los fármacos , Trastornos Cerebrovasculares/tratamiento farmacológico , Inhibidores Enzimáticos/metabolismo , Inmunosupresores/farmacología , Esfingosina/análogos & derivados , Tacrolimus/farmacología , Animales , Proteínas Reguladoras de la Apoptosis , Química Encefálica/efectos de los fármacos , Química Encefálica/genética , Trastornos Cerebrovasculares/metabolismo , Inhibidores Enzimáticos/farmacología , Proteína Ligando Fas , Expresión Génica/efectos de los fármacos , Humanos , Ataque Isquémico Transitorio/tratamiento farmacológico , Ataque Isquémico Transitorio/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Necrosis , Neuroblastoma , Neuronas/efectos de los fármacos , Neuronas/patología , Neuronas/fisiología , Proteínas Proto-Oncogénicas c-jun/genética , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Transducción de Señal/efectos de los fármacos , Esfingosina/biosíntesis , Esfingosina/farmacología , Ligando Inductor de Apoptosis Relacionado con TNF , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo , Factor de Necrosis Tumoral alfa/genética , Regulación hacia Arriba/efectos de los fármacos
20.
J Neurosci ; 19(10): 3809-17, 1999 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10234013

RESUMEN

Programmed cell death plays an important role in the neuronal degeneration after cerebral ischemia, but the underlying mechanisms are not fully understood. Here we examined, in vivo and in vitro, whether ischemia-induced neuronal death involves death-inducing ligand/receptor systems such as CD95 and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). After reversible middle cerebral artery occlusion in adult rats, both CD95 ligand and TRAIL were expressed in the apoptotic areas of the postischemic brain. Further recombinant CD95 ligand and TRAIL proteins induced apoptosis in primary neurons and neuron-like cells in vitro. The immunosuppressant FK506, which most effectively protects against ischemic neurodegeneration, prevented postischemic expression of these death-inducing ligands both in vivo and in vitro. FK506 also abolished phosphorylation, but not expression, of the c-Jun transcription factor involved in the transcriptional control of CD95 ligand. Most importantly, in lpr mice expressing dysfunctional CD95, reversible middle cerebral artery occlusion resulted in infarct volumes significantly smaller than those found in wild-type animals. These results suggest an involvement of CD95 ligand and TRAIL in the pathophysiology of postischemic neurodegeneration and offer alternative strategies for the treatment of cardiovascular brain disease.


Asunto(s)
Apoptosis/fisiología , Ataque Isquémico Transitorio/fisiopatología , Glicoproteínas de Membrana/inmunología , Glicoproteínas de Membrana/fisiología , Proteínas del Tejido Nervioso/fisiología , Factor de Necrosis Tumoral alfa/fisiología , Receptor fas/inmunología , Animales , Apoptosis/inmunología , Proteínas Reguladoras de la Apoptosis , Células Cultivadas , Proteína Ligando Fas , Femenino , Etiquetado Corte-Fin in Situ , Ataque Isquémico Transitorio/patología , Ligandos , Masculino , Ratones , Ratones Endogámicos C57BL , Neuronas/inmunología , Neuronas/patología , Neuronas/fisiología , Fosforilación , Ratas , Ratas Sprague-Dawley , Ligando Inductor de Apoptosis Relacionado con TNF , Células Tumorales Cultivadas
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