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2.
Br J Dermatol ; 183(4): 673-683, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32128788

RESUMEN

BACKGROUND: Psychological stress is commonly cited as a risk factor for melanoma, but clinical evidence is limited. OBJECTIVES: This study aimed to evaluate the association between partner bereavement and (i) first-time melanoma diagnosis and (ii) mortality in patients with melanoma. METHODS: We conducted two cohort studies using data from the U.K. Clinical Practice Research Datalink (1997-2017) and Danish nationwide registries (1997-2016). In study 1, we compared the risk of first melanoma diagnosis in bereaved vs. matched nonbereaved people using stratified Cox regression. In study 2 we estimated hazard ratios (HRs) for death from melanoma in bereaved compared with nonbereaved individuals with melanoma using Cox regression. We estimated HRs separately for the U.K. and for Denmark, and then pooled the data to perform a random-effects meta-analysis. RESULTS: In study 1, the pooled adjusted HR for the association between partner bereavement and melanoma diagnosis was 0·88 [95% confidence interval (CI) 0·84-0·92] across the entire follow-up period. In study 2, we observed increased melanoma-specific mortality in people experiencing partner bereavement across the entire follow-up period (HR 1·17, 95% CI 1·06-1·30), with the peak occurring during the first year of follow-up (HR 1·31, 95% CI 1·07-1·60). CONCLUSIONS: We found decreased risk of melanoma diagnosis, but increased mortality associated with partner bereavement. These findings may be partly explained by delayed detection resulting from the loss of a partner who could notice skin changes. Stress may play a role in melanoma progression. Our findings indicate the need for a low threshold for skin examination in individuals whose partners have died. What is already known about this topic? Psychological stress has been proposed as a risk factor for the development and progression of cancer, including melanoma, but evidence is conflicting. Clinical evidence is limited by small sample sizes, potential recall bias associated with self-report, and heterogeneous stress definitions. What does this study add? We found a decreased risk of melanoma diagnosis, but increased mortality associated with partner bereavement. While stress might play a role in the progression of melanoma, an alternative explanation is that bereaved people no longer have a close person to help notice skin changes, leading to delayed melanoma detection. Linked Comment: Talaganis et al. Br J Dermatol 2020; 183:607-608.


Asunto(s)
Aflicción , Melanoma , Estudios de Cohortes , Dinamarca/epidemiología , Humanos , Sistema de Registros , Factores de Riesgo , Estrés Psicológico/epidemiología
3.
Br J Dermatol ; 183(2): 321-331, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31782133

RESUMEN

BACKGROUND: Stress is commonly cited as a risk factor for psoriasis and atopic eczema, but such evidence is limited. OBJECTIVES: To investigate the association between partner bereavement (an extreme life stressor) and psoriasis or atopic eczema. METHODS: We conducted cohort studies using data from the U.K. Clinical Practice Research Datalink (1997-2017) and Danish nationwide registries (1997-2016). The exposed cohort was partners who experienced partner bereavement. The comparison cohort was up to 10 nonbereaved partners, matched to each bereaved partner by age, sex, county of residence (Denmark) and general practice (U.K.). Outcomes were the first recorded diagnosis of psoriasis or atopic eczema. We estimated hazard ratios (HRs) and confidence intervals (CIs) using a stratified Cox proportional hazards model in both settings, which were then pooled in a meta-analysis. RESULTS: The pooled adjusted HR for the association between bereavement and psoriasis was 1·01 (95% CI 0·98-1·04) across the entire follow-up. Similar results were found in other shorter follow-up periods. Pooled adjusted HRs for the association between bereavement and atopic eczema were 0·97 (95% CI 0·84-1·12) across the entire follow-up, 1·09 (95% CI 0·86-1·38) within 0-30 days, 1·18 (95% CI 1·04-1·35) within 0-90 days, 1·14 (95% CI 1·06-1·22) within 0-365 days and 1·07 (95% CI 1·02-1·12) within 0-1095 days. CONCLUSIONS: We found a modest increase in the risk of atopic eczema within 3 years following bereavement, which peaked in the first 3 months. Acute stress may play a role in triggering onset of new atopic eczema or relapse of atopic eczema previously in remission. We observed no evidence for increased long-term risk of psoriasis and atopic eczema following bereavement.


Asunto(s)
Aflicción , Dermatitis Atópica , Psoriasis , Estudios de Cohortes , Dinamarca/epidemiología , Dermatitis Atópica/epidemiología , Dermatitis Atópica/etiología , Humanos , Psoriasis/epidemiología , Factores de Riesgo
4.
Osteoarthritis Cartilage ; 27(7): 979-993, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31028883

RESUMEN

OBJECTIVE: Falls are common after total hip arthroplasty (THA) and total knee arthroplasty (TKA). While previous studies have investigated various risk factors for falls in patients following THA and TKA, no systematic reviews have summarized these risk factors. Therefore, the current systematic review aimed to summarize evidence regarding risk factors for falls in patients after THA and/or TKA. METHODS: MEDLINE, EMBASE, CINAHL, SPORTDiscus, and Physiotherapy Evidence Database (from inception to June 30, 2018) were searched. The methodological quality and quality of evidence of the included studies were assessed by two independent reviewers. Relevant data regarding participants' characteristics, study design, follow-up time points, and identified risk factors were extracted. Meta-analyses and narrative syntheses were performed. RESULTS: Twelve studies with a total of 1,292,689 participants were included. Twenty-nine identified risk factors for post-THA/TKA falls were classified into either inpatient or post-discharge risk factors. Key risk factors for both post-THA and/or post-TKA inpatient falls that showed moderate level of evidence included: postoperative complications or comorbidities and revision THA/TKA. Likewise, risk factors for post-discharge falls after THA and/or TKA that demonstrated moderate level of evidence included: medications, psychiatric diseases, living alone, prior history of TKA, falls history and female gender. The quality of the included studies varied and sample sizes were not justified. CONCLUSIONS: This review summarized both non-modifiable and modifiable risk factors for post-THA/TKA falls. Our findings highlight the importance of developing strategies to lower the falls risk among patients following THA/TKA.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Artroplastia de Reemplazo de Cadera/métodos , Artroplastia de Reemplazo de Rodilla/métodos , Osteoartritis de la Cadera/cirugía , Osteoartritis de la Rodilla/cirugía , Accidentes por Caídas/prevención & control , Factores de Edad , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/diagnóstico por imagen , Osteoartritis de la Rodilla/diagnóstico por imagen , Prevalencia , Pronóstico , Medición de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales
5.
Mucosal Immunol ; 10(2): 470-480, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27301880

RESUMEN

Treatment of post-transplant patients with immunosuppressive drugs targeting the calcineurin-nuclear factor of activated T cells (NFAT) pathway, including cyclosporine A or tacrolimus, is commonly associated with a higher incidence of opportunistic infections, such as Aspergillus fumigatus, which can lead to severe life-threatening conditions. A component of the A. fumigatus cell wall, ß-glucan, is recognized by dendritic cells (DCs) via the Dectin-1 receptor, triggering downstream signaling that leads to calcineurin-NFAT binding, NFAT translocation, and transcription of NFAT-regulated genes. Here, we address the question of whether calcineurin signaling in CD11c-expressing cells, such as DCs, has a specific role in the innate control of A. fumigatus. Impairment of calcineurin in CD11c-expressing cells (CD11ccrecnb1loxP) significantly increased susceptibility to systemic A. fumigatus infection and to intranasal infection in irradiated mice undergoing bone marrow transplant. Global expression profiling of bone marrow-derived DCs identified calcineurin-regulated processes in the immune response to infection, including expression of pentraxin-3, an important antifungal defense protein. These results suggest that calcineurin inhibition directly impairs important immunoprotective functions of myeloid cells, as shown by the higher susceptibility of CD11ccrecnbloxP mice in models of systemic and invasive pulmonary aspergillosis, including after allogeneic bone marrow transplantation. These findings are relevant to the clinical management of transplant patients with severe Aspergillus infections.


Asunto(s)
Aspergilosis/inmunología , Aspergillus fumigatus/inmunología , Trasplante de Médula Ósea , Proteína C-Reactiva/metabolismo , Calcineurina/metabolismo , Células Dendríticas/inmunología , Inmunosupresores/efectos adversos , Componente Amiloide P Sérico/metabolismo , Animales , Proteína C-Reactiva/genética , Antígeno CD11c/metabolismo , Calcineurina/genética , Inhibidores de la Calcineurina/efectos adversos , Inhibidores de la Calcineurina/uso terapéutico , Células Cultivadas , Susceptibilidad a Enfermedades , Regulación hacia Abajo , Rechazo de Injerto/prevención & control , Humanos , Inmunosupresores/uso terapéutico , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Componente Amiloide P Sérico/genética , Transducción de Señal
6.
Neuroscience ; 242: 110-27, 2013 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-23506738

RESUMEN

Glycine acts as a neuromodulator to regions rich in glutamatergic synapses, such as the forebrain. However, recent evidences for synaptic release of glycine in hippocampal cultured neurons and synaptosomes argue for the existence of functional glycinergic synapses in the hippocampus. It is well established that GABA and glycine act in concert at inhibitory synapses, while the existence of synapses which utilize both glutamate and glycine is less common. The purpose of the present study was to investigate the distribution of glycine and its role in hippocampal neurotransmission. Using immunohistochemistry, we demonstrate that vesicular glycine is preferentially stored in glutamatergic, rather than GABAergic presynaptic terminals. Using the sniffer patch technique, we found that glycine could be released upon presynaptic activity. Furthermore, using whole-cell patch-clamp recordings, we show for the first time the presence of a postsynaptic strychnine-sensitive chloride current in response to presynaptic stimulation. The small amplitude of this current is likely due to the paucity of postsynaptic glycine receptors rather than a low level of glycine release. Taken together, our results suggest that glycine is stored in glutamatergic presynaptic terminals. It is likely that the major role of glycine that is released from presynaptic terminals is to modulate N-methyl-d-aspartate receptor function but may also play a role in decreasing neuronal excitability by opposing glutamatergic neurotransmission in pathological states such as epilepsy or ischemia.


Asunto(s)
Ácido Glutámico/metabolismo , Glicina/metabolismo , Hipocampo/metabolismo , Terminales Presinápticos/metabolismo , Vesículas Sinápticas/metabolismo , Animales , Tronco Encefálico/metabolismo , Células CHO , Cricetulus , Glutamato Descarboxilasa/metabolismo , Glicina/fisiología , Hipocampo/fisiología , Potenciales de la Membrana/fisiología , Ratones , Neuronas/metabolismo , Neuronas/fisiología , Terminales Presinápticos/fisiología , Receptores de Glicina/metabolismo , Receptores de Glicina/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Transmisión Sináptica/fisiología , Ácido gamma-Aminobutírico/metabolismo
7.
Obes Rev ; 14(5): 383-92, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23331711

RESUMEN

Lorcaserin is a new anti-obesity drug recently approved by US Food and Drug Administration. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the association of lorcaserin therapy with weight loss and adverse events in obese adults (18-65 years old). Weight loss of 3.23 kg (95% confidence interval [CI]: 2.70, 3.75) and body mass index reduction of 1.16 kg m⁻² (95% CI: 0.98, 1.34) was observed compared with placebo in RCTs of 1 year duration. The use of lorcaserin for 8 and 12 weeks reduced weight of 1.60 kg (95% CI: 0.34, 2.86) and 2.9 kg (95% CI: 2.2, 3.5), respectively. In comparison to placebo, lorcaserin decreased waist circumference, blood pressure, total cholesterol, low-density lipoprotein-cholesterol and triglycerides, however did not statistically affect heart rate or high-density lipoprotein-cholesterol. Headache, nausea and dizziness were found to be significantly higher in the patients receiving lorcaserin than patients receiving placebo, whereas diarrhoea is no more likely than in patients receiving placebo. In conclusion, lorcaserin achieves modest weight loss and appears to be well tolerated. Clinical and pharmacovigilance studies with longer study duration are needed to inform of the long-term efficacy and safety of lorcaserin.


Asunto(s)
Fármacos Antiobesidad/uso terapéutico , Benzazepinas/uso terapéutico , Obesidad/tratamiento farmacológico , Adolescente , Adulto , Anciano , Fármacos Antiobesidad/efectos adversos , Benzazepinas/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento , Pérdida de Peso/efectos de los fármacos , Adulto Joven
8.
Oncogene ; 30(41): 4219-30, 2011 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-21516125

RESUMEN

P73 is important in drug-induced apoptosis in some cancer cells, yet its role in the regulation of chemosensitivity in ovarian cancer (OVCA) is poorly understood. Furthermore, if and how the deregulation of p73-mediated apoptosis confers resistance to cisplatin (CDDP) treatment is unclear. Here we demonstrate that TAp73α over-expression enhanced CDDP-induced PARP cleavage and apoptosis in both chemosensitive (OV2008 and A2780s) and their resistant counterparts (C13* and A2780cp) and another chemoresistant OVCA cells (Hey); in contrast, the effect of ΔNp73α over-expression was variable. P73α downregulation attenuated CDDP-induced PUMA and NOXA upregulation and apoptosis in OV2008 cells. CDDP decreased p73α steady-state protein levels in OV2008, but not in C13*, although the mRNA expression was identical. CDDP-induced p73α downregulation was mediated by a calpain-dependent pathway. CDDP induced calpain activation and enhanced its cytoplasmic interaction and co-localization with p73α in OV2008, but not C13* cells. CDDP increased the intracellular calcium concentration ([Ca(2+)](i)) in OV2008 but not C13* whereas cyclopiazonic acid (CPA), a Ca(2+)-ATPase inhibitor, caused this response and calpain activation, p73α processing and apoptosis in both cell types. CDDP-induced [Ca(2+)](i) increase in OV2008 cells was not effected by the elimination of extracellular Ca(2+), but this was attenuated by the depletion of internal Ca(2+) store, indicating that mobilization of intracellular Ca(2+]) stores was potentially involved. These findings demonstrate that p73α and its regulation by the Ca(2+)-mediated calpain pathway are involved in CDDP-induced apoptosis in OVCA cells and that dysregulation of Ca(2+)/calpain/p73 signaling may in part be the pathophysiology of CDDP resistance. Understanding the cellular and molecular mechanisms of chemoresistance will direct the development of effective strategies for the treatment of chemoresistant OVCA.


Asunto(s)
Apoptosis/efectos de los fármacos , Calcio/metabolismo , Calpaína/metabolismo , Cisplatino/farmacología , Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Antineoplásicos/farmacología , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Western Blotting , Calpaína/antagonistas & inhibidores , Calpaína/genética , Línea Celular Tumoral , Inhibidores de Cisteína Proteinasa/farmacología , Proteínas de Unión al ADN/genética , Dipéptidos/farmacología , Resistencia a Antineoplásicos , Femenino , Humanos , Inmunoprecipitación , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Proteínas Nucleares/genética , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Unión Proteica/efectos de los fármacos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Interferencia de ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína Tumoral p73 , Proteínas Supresoras de Tumor/genética
9.
Phys Rev Lett ; 102(10): 105002, 2009 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-19392121

RESUMEN

A large density cavity that measured 2000 km across and 500 km in height was observed by DEMETER and Formosat/COSMIC satellites in temporal and spatial relation to a new mode of propagation of electromagnetic (em) pulses between discrete magnetic field-aligned auroral plasmas to high altitudes. Recorded positive plasma potential from satellite probes is consistent with the expulsion of electrons in the creation of density cavities. High-frequency decay spectra support the concept of parametric instabilities fed by free energy sources.

10.
J Med Ethics ; 33(5): 261-5, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17470500

RESUMEN

OBJECTIVES: To study the attitudes of both medical and non-medical students towards the do-not-resuscitate (DNR) decision in a university in Hong Kong, and the factors affecting their attitudes. METHODS: A questionnaire-based survey conducted in the campus of a university in Hong Kong. Preferences and priorities of participants on cardiopulmonary resuscitation in various situations and case scenarios, experience of death and dying, prior knowledge of DNR and basic demographic data were evaluated. RESULTS: A total of 766 students participated in the study. There were statistically significant differences in their DNR decisions in various situations between medical and non-medical students, clinical and preclinical students, and between students who had previously experienced death and dying and those who had not. A prior knowledge of DNR significantly affected DNR decision, although 66.4% of non-medical students and 18.7% of medical students had never heard of DNR. 74% of participants from both medical and non-medical fields considered the patient's own wish as the most important factor that the healthcare team should consider when making DNR decisions. Family wishes might not be decisive on the choice of DNR. CONCLUSIONS: Students in medical and non-medical fields held different views on DNR. A majority of participants considered the patient's own wish as most important in DNR decisions. Family wishes were considered less important than the patient's own wishes.


Asunto(s)
Actitud del Personal de Salud , Toma de Decisiones , Órdenes de Resucitación/ética , Valores Sociales , Estudiantes de Medicina/psicología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Actitud Frente a la Muerte , Ética Profesional , Femenino , Hong Kong , Humanos , Masculino , Persona de Mediana Edad , Defensa del Paciente , Guías de Práctica Clínica como Asunto , Órdenes de Resucitación/psicología , Encuestas y Cuestionarios
12.
J Thromb Haemost ; 4(12): 2623-8, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17002658

RESUMEN

BACKGROUND: During infancy, a male patient experienced several life-threatening bleeding episodes. Standard coagulation tests revealed that the patient's plasma prothrombin activity was 8%, while his father's and mother's levels were 74% and 62%, respectively. OBJECTIVES: A molecular genetic approach was used to determine the molecular basis of prothrombin deficiency within the family. PATIENT/METHODS: Prothrombin genomic DNA fragments were amplified by using the polymerase chain reaction (PCR). In addition, liver cDNA fragments were amplified from the patient by using reverse transcription (RT) and PCR. The nucleotide sequences of the DNA fragments were determined. RESULTS: A novel, heterozygous point mutation (g.1755 G > A, named prothrombin-Edmonton) was detected in the patient and his mother, resulting in the mutation of Arg-4 in the prothrombin propeptide to Gln (R-4Q). RT-PCR analysis of the patient's liver sample demonstrated the presence of two mRNA transcripts that differed by the presence or absence of exon 11. Real-time PCR analysis on genomic DNA and cDNA confirmed a deletion (g.10435_10809del) in the paternal allele. CONCLUSIONS: The patient has a maternally-inherited point mutation (R-4Q) and a paternally-inherited deletion. By analogy with the previously reported factor IX San Dimas, the R-4Q mutation probably causes under-carboxylation of prothrombin and poor cleavage of the propeptide in the hepatocyte. The deletion probably results in a polypeptide that lacks 50 amino acids from the protease domain; this is likely to impair folding, secretion, stability and/or activity of the truncated prothrombin. The two mutations combine to give the prothrombin deficiency observed in the patient.


Asunto(s)
Eliminación de Gen , Hipoprotrombinemias/genética , Mutación Missense , Mutación Puntual , Protrombina/genética , ADN Complementario/genética , Exones/genética , Humanos , Hipoprotrombinemias/sangre , Lactante , Masculino , Linaje , Reacción en Cadena de la Polimerasa , Protrombina/metabolismo , Análisis de Secuencia de ADN
13.
Eur J Anaesthesiol ; 23(7): 586-90, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16507198

RESUMEN

BACKGROUND AND OBJECTIVES: This was a prospective audit to assess the incidence and characteristics of early postoperative complications in the recovery room in extubated patients after elective neurosurgical procedures using propofol and remifentanil-based total intravenous anaesthesia. METHODS: Vital signs (temperature, conscious level, respiratory rate, oxygen saturation, pulse and blood pressure) and postoperative complications (shivering, nausea, vomiting and cardiorespiratory) were analysed in 145 adult patients over a 1-yr period. RESULTS: The overall shivering, postoperative nausea and vomiting and postoperative hypertension (systolic blood pressure more than 25% of the preoperative value) incidences were 30.3%, 16.6% and 35.2%, respectively. Fifty-one percent of the patients had at least one of the above complications. The complication rates were found to be widely different among various types of neurosurgery. The surgical procedures were divided into five groups: supratentorial craniotomy, posterior fossa craniotomy, intracranial vascular procedures, transphenoidal hypophysectomy and extracranial procedures. Median extubation time was similar in all groups and patients were fully conscious with no hypoxia in the recovery room. The intracranial vascular group had the highest shivering and postoperative nausea and vomiting rates (58.8% and 29.4%, respectively). In the supratentorial craniotomy group, 46% of the patients had hypertension. The overall complication rate (presence of any complications) was highest in the supratentfial craniotomy (55.4%), posterior fossa craniotomy (75%) and intracranial vascular (76.5%) groups. Shivering and overall complication rate was significantly related to the anaesthetic time (P

Asunto(s)
Anestesia Intravenosa , Auditoría Médica , Procedimientos Neuroquirúrgicos , Piperidinas/farmacología , Complicaciones Posoperatorias/inducido químicamente , Propofol/farmacología , Humanos , Complicaciones Posoperatorias/patología , Sala de Recuperación , Remifentanilo , Factores de Tiempo
14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(4 Pt 2): 046401, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16383539

RESUMEN

The interaction of a petawatt laser with a small solid-density plasma bunch is studied by particle-in-cell simulation. It is shown that when irradiated by a laser of intensity >10(21) W/cm2, a dense plasma bunch of micrometer size can be efficiently accelerated. The kinetic energy of the ions in the high-density region of the plasma bunch can exceed ten MeV at a density in the 10(23)-cm(-3) level. Having a flux density orders of magnitude higher than that of the traditional charged-particle pulses, the laser-accelerated plasma bunch can have a wide range of applications. In particular, such a dense energetic plasma bunch impinging on the compressed fuel in inertial fusion can significantly enhance the nuclear-reaction cross section and is thus a promising alternative for fast ignition.

16.
Anaesthesia ; 60(8): 811-3, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16029232

RESUMEN

A 49-year-old male with neurofibromatosis type II was scheduled for posterior fossa craniotomy and excision of a right acoustic neuroma and placement of an auditory brainstem implant in the sitting position. Intra-operatively, the patient was monitored with transoesophageal echocardiography which detected two major episodes of venous air embolism. Despite immediate treatment the patient's gas exchange progressively worsened during surgery and a chest X-ray showed extensive bilateral pulmonary infiltrates. The patient developed acute respiratory distress syndrome and required inotropic support in the intensive care unit. Although transoesophageal echocardiography allowed rapid detection of venous air embolism, there was no evidence of therapeutic benefit.


Asunto(s)
Embolia Aérea/etiología , Complicaciones Intraoperatorias/etiología , Monitoreo Intraoperatorio/métodos , Neuroma Acústico/cirugía , Craneotomía , Ecocardiografía Transesofágica , Embolia Aérea/diagnóstico por imagen , Humanos , Complicaciones Intraoperatorias/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Postura , Síndrome de Dificultad Respiratoria/etiología
20.
Pflugers Arch ; 444(5): 663-9, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12194020

RESUMEN

The study of synaptic transmission in brain slices generally entails the patch-clamping of postsynaptic neurones and stimulation of identified presynaptic axons using a remote electrical stimulating electrode. Although patch recording from postsynaptic neurones is routine, many presynaptic axons take tortuous turns and are severed in the slicing procedure, blocking propagation of the action potential to the synaptic terminal and preventing synaptic stimulation. Here we demonstrate a method of using calcium imaging to select postsynaptic cells with functional synaptic inputs prior to patch-clamp recording. We have used this method for exploring transmission in the auditory brainstem at the medial nucleus of the trapezoid body neurones, which are innervated by axons from the contralateral cochlear nucleus. Brainstem slices were briefly loaded with the calcium indicator fura-2 AM and stimulated with an electrode placed on the midline. Electrical stimulation caused a rise in intracellular calcium concentration in those postsynaptic neurones with active synaptic connections. Since <10% of the medial nucleus of the trapezoid body neurones retain viable synaptic inputs following the slicing procedure, preselecting those cells with active synapses dramatically increased our recording success. This detection method will greatly ease the study of synaptic responses in brain areas where suprathreshold synaptic inputs occur but connectivity is sparse.


Asunto(s)
Calcio/metabolismo , Núcleo Coclear/citología , Núcleo Coclear/fisiología , Sinapsis/fisiología , Animales , Vías Auditivas/citología , Vías Auditivas/fisiología , Estimulación Eléctrica , Colorantes Fluorescentes , Fura-2 , Ratas , Ratas Endogámicas
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