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1.
HNO ; 67(7): 502-509, 2019 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-31165200

RESUMEN

The current article is an experience report on the establishment of an ENT clinic in Asmara/Eritrea and the organization of regular work stays for the further education of local colleagues. Objectives of the project are content and structural support for self-help and thus achievement of sustainable development aid, which benefits both the medical development of the country and the care of the local patients.


Asunto(s)
Atención a la Salud , Eritrea , Humanos
2.
HNO ; 63(11): 747-51, 2015 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-26507713

RESUMEN

BACKGROUND: Reconstruction of defects after extirpation of head and neck neoplasms is a highly challenging and complex surgical undertaking. Commonly used techniques, such as the radial forearm flap or anterior lateral thigh flap, have numerous disadvantages, e.g., donor-site morbidity, poor color match for cutaneous reconstruction, and excessive tissue bulk for intraoral reconstruction. Use of a submental artery island flap is a relatively new and increasingly performed option for reconstruction in the head and neck region. MATERIALS AND METHODS: From March 2013 to August 2015, 12 patients were treated with a submental island flap after surgical resection of intraoral carcinomas or cutaneous neoplasms of the lower half of the face. CASE DESCRIPTION: This paper reports on two cases. The first case describes reconstruction of the floor of the mouth using a pull-through technique after resection of a squamous cell carcinoma. The submental flap was pedicled on the contralateral side, since neck dissection of regions I-V had been performed on the ipsilateral side. The second case is a reconstruction of the lower midface with parts of the upper lip, after removal of a cutaneous spinalioma. In a N0 neck, no neck dissection was performed. The flap healed without problems in both patients, leading to a very good functional and cosmetic outcome. CONCLUSION: The submental island flap demonstrates reliability and versatility for head and neck reconstructions. Its minimal donor site morbidity, excellent cosmetic match, pliability, and relative ease of dissection and application confer a definite advantage over distant flaps.


Asunto(s)
Neoplasias Faciales/cirugía , Neoplasias de la Boca/cirugía , Procedimientos de Cirugía Plástica/métodos , Neoplasias Cutáneas/cirugía , Colgajos Quirúrgicos/irrigación sanguínea , Colgajos Quirúrgicos/trasplante , Anciano , Neoplasias Faciales/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/diagnóstico , Neoplasias Cutáneas/diagnóstico , Resultado del Tratamiento
3.
Neurobiol Dis ; 63: 62-73, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24291517

RESUMEN

Disruption of neuronal networks in the Alzheimer-afflicted brain is increasingly recognized as a key correlate of cognitive and memory decline in Alzheimer patients. We hypothesized that functional synaptic disconnections within cortical columnar microcircuits by pathological ß-amyloid accumulation, rather than cell death, initially causes the cognitive impairments. During development of cortical ß-amyloidosis with still few plaques in the transgenic 5xFAD mouse model single cell resolution mapping of neuronal thallium uptake revealed that electrical activity of pyramidal cells breaks down throughout infragranular cortical layer V long before cell death occurs. Treatment of 5xFAD mice with the glutaminyl cyclase inhibitor, PQ 529, partially prevented the decline of pyramidal cell activity, indicating pyroglutamate-modified forms, potentially mixed oligomers of Aß are contributing to neuronal impairment. Laminar investigation of cortical circuit dysfunction with current source density analysis identified an early loss of excitatory synaptic input in infragranular layers, linked to pathological recurrent activations in supragranular layers. This specific disruption of normal cross-laminar cortical processing coincided with a decline of contextual fear learning.


Asunto(s)
Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Corteza Cerebral/patología , Placa Amiloide/etiología , Factores de Edad , Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Muerte Celular/fisiología , Corteza Cerebral/metabolismo , Condicionamiento Psicológico , Modelos Animales de Enfermedad , Miedo , Análisis de Fourier , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación/genética , Neuronas/metabolismo , Neuronas/patología , Placa Amiloide/genética , Presenilina-1/genética , Talio
4.
Laryngorhinootologie ; 93(2): 87-94, 2014 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-23929209

RESUMEN

A new and interdisciplinary S2k AWMF guideline for the treatment of obstructive sialadenitis has been published. There have been several technical achievements, for instance in the field of ultrasonography, via sialendoscopy, or by MR-sialography, that have increased the possibilities for diagnosis and treatment of patients with obstructive sialadenitis. In the past, the treatment of choice in case of unsuccessful medical treatment was a complete extirpation of the affected salivary gland. Nowadays, using a variety of modern treatment options (like sialendoscopy, or extracorporeal shock-waves lithotripsy sometimes combined with salivary duct incision), it is possible in most patients, especially in cases of sialolithiasis, to preserve the affected gland. A functional recovery after gland-sparing surgery is described but more data is needed to finally evaluate the long-time results. The new guideline describes all relevant steps to diagnose an obstructive sialadenitis and values all diagnostic tools critically. Finally, all recommendable therapy options are described and valued, too.


Asunto(s)
Cálculos del Conducto Salival/terapia , Sialadenitis/terapia , Constricción Patológica/diagnóstico , Constricción Patológica/etiología , Constricción Patológica/terapia , Diagnóstico Diferencial , Endoscopía , Humanos , Litotricia , Imagen por Resonancia Magnética , Parotiditis/diagnóstico , Parotiditis/etiología , Parotiditis/terapia , Cálculos del Conducto Salival/diagnóstico , Cálculos del Conducto Salival/etiología , Conductos Salivales/cirugía , Sialadenitis/diagnóstico , Sialadenitis/etiología , Sialografía , Enfermedades de la Glándula Submandibular/diagnóstico , Enfermedades de la Glándula Submandibular/etiología , Enfermedades de la Glándula Submandibular/terapia , Ultrasonografía
5.
Strahlenther Onkol ; 189(7): 559-65, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23700207

RESUMEN

BACKGROUND AND PURPOSE: This study investigated the prognostic role of tumor cell expression of erythropoietin (EPO) and its receptor (EPO-R) in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN) treated with surgery plus radiotherapy. PATIENTS AND METHODS: The impact of EPO, EPO-R, and 11 additional factors on locoregional control (LRC), metastases-free survival (MFS), and overall survival (OS) was retrospectively evaluated in 144 patients. Additional factors were age, gender, performance status, preradiotherapy (pre-RT) hemoglobin levels, tumor site, histologic grade, T category, N category, human papillomavirus (HPV) status, extent of resection, and chemotherapy. Univariate analyses were performed with the Kaplan-Meier method and the log-rank test, multivariate analyses with the Cox proportional hazard model. RESULTS: On multivariate analysis, improved LRC was significantly associated with no EPO expression (risk ratio [RR] 3.72; 95 % confidence interval [CI] 1.35-15.42; p = 0.008), lower T category (RR 1.60; 95 %CI 1.14-2.32; p = 0.005), and oropharynx or larynx cancer (RR 1.23; 95 %CI 1.02-1.49; p = 0.033). Improved MFS was significantly associated with no EPO expression (RR 5.45; 95 %CI 1.13-97.81; p = 0.031), lower T category (RR 1.66; 95 %CI 1.11-2.65; p = 0.013), lower N category (RR 2.44; 95 %CI 1.04-6.66; p = 0.039), HPV positivity (RR 3.14; 95 %CI not available; p = 0.034), and oropharynx or larynx cancer (RR 1.28; 95 %CI 1.01-1.61; p = 0.041). Improved OS was significantly associated with no EPO expression (RR 4.77; 95 %CI 1.63-20.68; p = 0.003), no EPO-R expression (RR 2.36; 95 %CI 1.22-4.92; p = 0.010), lower T category (RR 1.44; 95 %CI 1.04-2.04; p = 0.027), oropharynx or larynx cancer (RR 1.30; 95 %CI 1.08-1.57; p = 0.007), and pre-RT hemoglobin ≥ 12 g/dl (RR 1.94; 95 %CI 1.03-3.65; p = 0.042). CONCLUSION: EPO expression of tumor cells was an independent prognostic factor for LRC, MFS, and OS. EPO-R expression was an independent prognostic factor for OS.


Asunto(s)
Carcinoma de Células Escamosas/patología , Eritropoyetina/análisis , Neoplasias Laríngeas/patología , Neoplasias Orofaríngeas/patología , Receptores de Eritropoyetina/análisis , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Quimioradioterapia Adyuvante , Terapia Combinada , Femenino , Humanos , Neoplasias Laríngeas/mortalidad , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirugía , Laringe/patología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Clasificación del Tumor , Neoplasias Orofaríngeas/mortalidad , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/cirugía , Orofaringe/patología , Pronóstico , Tasa de Supervivencia
6.
HNO ; 60(8): 725-9, 2012 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-22415538

RESUMEN

The preservation of the great auricular nerve in parotid gland surgery for benign disease is discussed controversially. The negative impact on quality of life due to lack of sensation in the auricle was underestimated in former times. Thus, more and more surgeons try to preserve the nerve with rising incidence of possible complications like neuralgia. We report on three patients with postoperative neuralgia of the great auricular nerve. Two patients experienced a long lasting remission of their neuralgia after an infiltration of the punctum nervosum with a local anesthetic. In a third patient the great auricular nerve had to be resected 6 months after parotidectomy. Other options of therapy are described.


Asunto(s)
Procedimientos Quirúrgicos Endocrinos/efectos adversos , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/cirugía , Glándula Parótida/inervación , Glándula Parótida/cirugía , Traumatismos de los Nervios Periféricos/diagnóstico , Traumatismos de los Nervios Periféricos/cirugía , Adulto , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/etiología , Traumatismos de los Nervios Periféricos/etiología , Resultado del Tratamiento
7.
N Biotechnol ; 53: 35-40, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31202859

RESUMEN

Comparison of published biomedical studies shows that a large proportion are irreproducible, causing severe damage to society and creating an image of wasted investments. These observations are of course damaging to the biomedical research field, which is currently full of future promise. Precision medicine and disease prevention are successful, but are progressing slowly due to irreproducible study results. Although standardization is mentioned as a possible solution, it is not always clear how this could decrease or prevent irreproducible results in biomedical studies. In this article more insight is given into what quality, norms, standardization, certification, accreditation and optimized infrastructure can accomplish to reveal causes of irreproducibility and increase reproducibility when collecting biomaterials. CEN and ISO standards for the sample pre-analytical phase are currently being developed with the support of the SPIDIA4P project, and their role in increasing reproducibility in both biomedical research and diagnostics is demonstrated. In particular, it is described how standardized methods and quality assurance documentation can be exploited as tools for: 1) recognition and rejection of 'not fit for purpose' samples on the basis of detailed sample metadata, and 2) identification of methods that contribute to irreproducibility which can be adapted or replaced.


Asunto(s)
Materiales Biocompatibles/análisis , Investigación Biomédica/normas , Fase Preanalítica/normas , Humanos , Reproducibilidad de los Resultados
8.
Neuroscience ; 157(2): 385-95, 2008 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-18832015

RESUMEN

In this study we evaluated the effects of the novel, potent non-competitive metabotropic glutamate receptor (mGluR) 1 antagonist (3aS,6aS)-6a-naphthalen-2-ylmethyl-5-methyliden-hexahydro-cyclopental[c]furan-1-on (BAY 36-7620) on different types of synaptic plasticity in the hippocampal cornu ammonis (CA) 1-region and on hippocampus-dependent spatial learning. After having confirmed the presence of mGluR1 in the hippocampal CA1 region of our rat strain by confocal microscopy, we tested the effects of BAY 36-7620 on: 1) long-term potentiation (LTP) induced by weak and strong stimulation; 2) 3,5-dihydroxyphenylglycine (DHPG, 30 microM)-induced depression of synaptic transmission; and 3) learning of the hidden platform version of the water maze by mice. BAY 36-7620 (10 microM) amplified LTP but, like the mGluR1 antagonists 7-hydroxyiminocyclopropan[b]chromen-1a-carboxylic acid ethyl ester (CPCCOEt, 10 microM) and 4-carboxyphenylglycine (4-CPG, 50 microM), diminished LTP at 1 microM. The mGluR5 antagonist 6-methyl-2-(phenylethynyl)-pyridine (MPEP, 10 microM) had no effect. BAY 36-7620 (10 microM) did not affect strong LTP. Thus, mGlu 1, but not mGlu 5, receptors modulate LTP elicited by weak stimulation in vitro. DHPG-induced depression of synaptic transmission was only marginally affected by BAY 36-7620 (1 microM) or 4-CPG (100 microM). In a mouse water maze study, BAY 36-7620 (10 mg/kg, i.v.) increased the escape latency and impaired water escape task acquisition during the first 4 days. Drug- and vehicle-treated groups showed comparable performance at day 5. Our data support a role for mGluR1 in LTP and in the acquisition of spatial memory.


Asunto(s)
Hipocampo/efectos de los fármacos , Aprendizaje por Laberinto/efectos de los fármacos , Naftalenos/farmacología , Plasticidad Neuronal/efectos de los fármacos , Receptores de Glutamato Metabotrópico/antagonistas & inhibidores , Transmisión Sináptica/efectos de los fármacos , Análisis de Varianza , Animales , Estimulación Eléctrica , Antagonistas de Aminoácidos Excitadores/farmacología , Hipocampo/citología , Masculino , Ratones , Ratones Noqueados , Técnicas de Placa-Clamp , Ratas , Receptores de Glutamato Metabotrópico/deficiencia
9.
HNO ; 56(4): 467-70, 2008 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-18345526

RESUMEN

BACKGROUND: Total aspiration is a rare complication after extended laser surgery for laryngeal cancer with adjuvant radiotherapy. PATIENTS AND METHODS: Two patients with long-standing total aspiration after laser surgery with radiotherapy despite intensified swallowing therapy were treated with an extended medialization thyroplasty. RESULTS: Postoperatively, both patients were able to swallow food and liquids without aspiration. One patient no longer has a gastrostomy tube and has been free from aspiration with normal oral food intake for 3 years. The second patient, with a tiny mucosal scar perforation, developed an abscess 2 months after surgery and needed revision surgery, with a subsequent return of aspiration. DISCUSSION: The second patient's complication stresses the significance of an intact endolaryngeal scar because of the well-known prolonged healing of mucosa in the irradiated larynx. In our opinion, the potential benefits of medialization thyroplasty outweigh the risk of significant complications, especially after irradiation.


Asunto(s)
Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirugía , Laringectomía/métodos , Terapia por Láser/efectos adversos , Aspiración Respiratoria/etiología , Aspiración Respiratoria/cirugía , Anciano , Humanos , Masculino , Persona de Mediana Edad , Radioterapia Adyuvante , Resultado del Tratamiento
10.
Bioelectrochemistry ; 121: 160-168, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29454193

RESUMEN

In this work we employ differential electrochemical mass spectrometry (DEMS) in combination with static and dynamic electrochemical techniques for the study of metabolic processes of electrochemically active bacteria. CO2 production during acetate oxidation by electrode respiring bacteria was measured, in-vivo and online with a sensitivity of 6.5 ⋅ 10-13 mol/s. The correlation of ion current and electrical current provides insight into the interaction of metabolic processes and extra-cellular electron transfer. In low-turnover CVs, two competing potential dependent electron transfer mechanisms were observed and formal potentials of two redox systems that are involved in complete oxidation of acetate to CO2 were determined. By balancing charge and carbon flows during dynamic measurements, two significant storage mechanisms in electrochemically active bacteria were identified: 1) a charge storage mechanism that allows substrate oxidation to proceed at a constant rate despite of external current flowing in cathodic direction. 2) a carbon storage mechanism that allows the biofilm to take up acetate at an unchanged rate at very low potentials even though the oxidation to CO2 stops. These storage capabilities allow a limited decoupling of electrical current and CO2 production rate.


Asunto(s)
Acetatos/metabolismo , Fuentes de Energía Bioeléctrica/microbiología , Biopelículas , Dióxido de Carbono/metabolismo , Geobacter/fisiología , Espectrometría de Masas/métodos , Biopelículas/crecimiento & desarrollo , Electricidad , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Transporte de Electrón , Diseño de Equipo , Espectrometría de Masas/instrumentación , Oxidación-Reducción
11.
HNO ; 55(13): 997-1000, 2007 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-17464494

RESUMEN

BACKGROUND: Cervical osteochondrosis is a rare differential diagnosis leading to dysphagia, inspiratory stridor and obstructive sleep apnea syndrome (OSAS). PATIENTS AND METHODS: We report six cases of patients with episodes of neck pain (n=6), pain reflected to the arm (n=1), sleep apnea (n=5), inspiratory stridor (n=3) and/or unclear dysphagia (n=6), who presented between 2000 and 2003 at the Römerwallklinik Mainz and the university hospitals of Mainz and Cologne. None of these patients had symptoms of spinal or radicular compression. All underwent otorhinolaryngological and radiological examination followed by excision of anterior spondylophytes and intervertebral fusion. One patient required immediate tracheotomy due to perforation of the pharyngeal wall associated with severe supraglottic swelling. RESULTS: All patients were free of inspiratory stridor postoperatively. Symptoms of dysphagia disappeared in four patients and were reduced in two. Three of five patients were free of apnea. OSAS had improved in two. Neck pain was eliminated in four cases and markedly improved in two cases. CONCLUSIONS: In case of symptoms of pharyngeal compression and OSAS, a vertebragenic cause should be considered.


Asunto(s)
Vértebras Cervicales , Dolor de Cuello/etiología , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/etiología , Osteofitosis Vertebral/complicaciones , Osteofitosis Vertebral/diagnóstico , Anciano , Anciano de 80 o más Años , Disnea/diagnóstico , Disnea/etiología , Disnea/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor de Cuello/diagnóstico , Dolor de Cuello/prevención & control , Apnea Obstructiva del Sueño/terapia , Osteofitosis Vertebral/cirugía , Resultado del Tratamiento
12.
Nanoscale ; 9(36): 13618-13629, 2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-28876003

RESUMEN

Metal nanoclusters, supported on inert substrates, exhibiting well-defined shapes and sizes in a broad range of temperatures are a major object of desire in nanotechnology. Here, a technique is presented that improves the thermal stability of monodisperse and crystalline transition metal nanoclusters grown in a regular array on metal-supported graphene. To stabilize the clusters after growth under ultrahigh vacuum the system composed of the aggregates and the graphene/metal interface is exposed to radicals resulting from the dissociation of diatomic gases. As a model system we have used Pt as the metal element for cluster growth and the template consisting of the moiré pattern resulting from the lattice mismatch between graphene and the Ir(111) surface. The study has been performed for deuterium and oxygen radicals, which interact very differently with graphene. Our results reveal that after radical exposure the thermally activated motion of Pt nanoclusters to adjacent moiré cells and the subsequent sintering of neighbor aggregates are avoided, most pronounced for the case of atomic O. For the case of D the limits of the improvement are given by radical desorption, whereas for the case of O they are defined by an interplay between coalescence and graphene etching followed by Pt intercalation, which can be controlled by the amount of exposure. Finally, we determined the mechanism of how radical adsorption improves the thermal stability of the aggregates.

13.
J Dairy Sci ; 89(1): 1-14, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16357263

RESUMEN

As the dairy cow uses body energy reserves in early lactation, body condition scoring has become an integral part of dairy herd management. Several methods based on visual and tactile evaluation have been developed. Problems caused by the subjectivity of these techniques have been reported. Alternative approaches to predict energy reserves or energy balance in dairy cattle include metabolic profiling and measurement of live weight, heart girth, or skinfold thickness. A less common method to assess fat reserves in body tissues is measuring backfat thickness (BFT) by using ultrasound. An ultrasound technique has been established to predict carcass quality in beef cattle. A new aspect is the application of ultrasound as a monitoring tool in dairy herd management where another location has to be evaluated. This technique has been validated by relating BFT to total body fat (TBF) content and carcass BFT. Backfat thickness also has been related to other methods of body condition scoring. Target values for the development of BFT throughout lactation are available. The relationship between BFT and TBF content is highly significant although biased by multiple factors. A change in BFT of 1 mm equates to approximately 5 kg of TBF content. Measuring BFT by ultrasound is of added value compared with other body condition scoring systems because it is objective and precise. Changes in body condition can be detected and evaluated properly.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Composición Corporal , Bovinos/fisiología , Ultrasonografía/veterinaria , Tejido Adiposo/metabolismo , Animales , Dorso , Peso Corporal , Metabolismo Energético , Femenino , Corazón/anatomía & histología , Lactancia/fisiología , Palpación/veterinaria , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Grosor de los Pliegues Cutáneos , Ultrasonografía/métodos
14.
Radiat Oncol ; 11: 6, 2016 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-26792072

RESUMEN

BACKGROUND AND PURPOSE: After the failure of first-line treatment, the clinical prognosis in head and neck cancer (HNSCC) deteriorates. Effective therapeutic strategies are limited due to the toxicity of previous treatments and the diminished tolerance of surrounding normal tissue. This study demonstrates a promising second-line regimen, with function preserving surgical tumor debulking, followed by a combination of postoperative interstitial brachytherapy and a simultaneous protocol of cetuximab and taxol. PATIENTS AND METHODS: From January 2006 to May 2013, 197 patients with HNSCC were treated with brachytherapy at the University Hospital Schleswig-Holstein Campus Lübeck, including 94 patients due to recurrent cancer. Within these, 18 patients were referred to our clinic because of early progressive disease following first- or second-line treatment failure. They received the new palliative regimen. A matched-pair analysis including recurrent tumor stage, status of resection margins, tissue invasion and previous therapy was performed to evaluate this treatment retrospectively. Overall survival (OS), disease-free survival (DFS), functional outcome and treatment toxicity was analyzed on the basis of medical records and follow-up data. RESULTS: DFS and OS of the study group were 8.7 and 14.8 months. Whereas, DFS and OS of the control group, treated only by function preserving tumor debulking and brachytherapy, was 3.9 and 6.1 months respectively. This demonstrates a positive trend through the additional use of the cetuximab-taxane protocol. Furthermore, no increase of therapy induced toxicities was displayed. CONCLUSION: Pre-treated patients with a further relapse benefit from the 'cetuximab-taxane recurrency scheme'. It seems to be a valuable complement to interdisciplinary and multimodal tumor therapy, which improves OS and results in acceptable toxicity.


Asunto(s)
Braquiterapia/métodos , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Cetuximab/administración & dosificación , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Paclitaxel/administración & dosificación , Anciano , Carcinoma de Células Escamosas/cirugía , Procedimientos Quirúrgicos de Citorreducción , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Persona de Mediana Edad , Cuidados Paliativos/métodos , Pronóstico , Estudios Retrospectivos , Terapia Recuperativa , Resultado del Tratamiento
15.
Nanoscale ; 8(4): 1932-43, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26426949

RESUMEN

Using scanning tunneling microscopy, the oxygen adsorbate superstructures on bare Ir(111) are identified and compared to the ones formed by intercalation in between graphene and the Ir(111) substrate. For bare Ir(111) we observe O-(2 × 2) and O-(2 × 1) structures, thereby clarifying a persistent uncertainty about the existence of these structures and the role of defects for their stability. For the case of graphene-covered Ir(111), oxygen intercalation superstructures can be imaged through the graphene monolayer by choosing proper tunneling conditions. Depending on the pressure, temperature and duration of O2 exposure as well as on the graphene morphology, O-(2 × 2), O-(√3×√3)-R30°, O-(2 × 1) and O-(2√3 × 2√3)-R30° superstructures with respect to Ir(111) are observed under the graphene cover. Two of these structures, the O-(√3 × âˆš3)-R30° and the (2√3 × 2√3)-R30° structure are only observed when the graphene layer is on top. Phase coexistence and formation conditions of the intercalation structures between graphene and Ir(111) are analyzed. The experimental results are compared to density functional theory calculations including dispersive forces. The existence of these phases under graphene and their absence on bare Ir(111) are discussed in terms of possible changes in the adsorbate-substrate interaction due to the presence of the graphene cover.

16.
Biochim Biophys Acta ; 913(2): 185-94, 1987 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-3593738

RESUMEN

The substrate-dependent kinetics of the carbon monoxide-inhibited cytochrome P-450 activity and its light reversibility is reinvestigated in microsomal preparations. In order to find out whether the substrate specificity is mediated by an isoenzyme-specific binding of carbon monoxide with different dissociation constants an experimental design has been chosen where it could be established that essentially the same isoenzyme component was involved in two different monooxygenase reactions, i.e., the O-dealkylation of 7-ethoxycoumarin and the 7-hydroxylation of coumarin. The dissociation constant kD(CO) of the ferrous cytochrome P-450 carbon monoxide complex is 6-fold higher in the presence of 7-ethoxycoumarin than in the presence of coumarin. But the light-induced relative changes of the Warburg partition coefficient for the 7-ethoxycoumarin deethylation and for coumarin 7-hydroxylation do not differ remarkably from each other. These relative changes are shown to represent the ratio of the photoinduced rate constant to the spontaneous rate constant of the dissociation for the ferrous cytochrome P-450 carbon monoxide complex. The differences in the dissociation constants are assigned to substrate specific effects on the carbon monoxide binding, indicating a substrate-specific change of the free binding enthalpy for carbon monoxide.


Asunto(s)
Monóxido de Carbono/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Isoenzimas/metabolismo , Microsomas Hepáticos/enzimología , Animales , Benzoflavonas/farmacología , Cumarinas/metabolismo , Sistema Enzimático del Citocromo P-450/efectos de la radiación , Concentración de Iones de Hidrógeno , Isoenzimas/efectos de la radiación , Cinética , Metirapona/farmacología , NADP/metabolismo , Especificidad por Sustrato , Porcinos
17.
Tuberculosis (Edinb) ; 85(1-2): 107-14, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15687034

RESUMEN

Today it is generally accepted that the Bacillus Calmette-Guerin (BCG) vaccine protects against childhood tuberculosis (TB) but this immunity wanes with age, resulting in insufficient protection against adult pulmonary TB. Hence, one possible strategy to improve the protective efficacy of the BCG vaccine would be to boost in adulthood. In this study, using the mouse model, we evaluated the ability of two new TB vaccine candidates, heat-killed BCG (H-kBCG) and arabinomannan-tetanus toxoid conjugate (AM-TT), given intransally in a novel Eurocine adjuvant, to boost a primary BCG-induced immune response and to improve protection. Young C57BL/6 mice were vaccinated with conventional BCG and, 6 months later, boosted intranasally with adjuvanted H-kBCG or AM-TT, or subcutaneously with BCG. Ten weeks after the booster, mice were challenged intravenously with M. tuberculosis (Mtb) strain H37Rv. In spleens, there was a significant reduction of cfu counts in mice boosted with either H-kBCG or AM-TT vaccines compared to the non-boosted BCG-vaccinated mice. None of the boosting regimens significantly reduced bacterial loads in lungs, compared to non-boosted BCG vaccination. However, the extent of granulomatous inflammation was significantly reduced in the lungs of mice that received two of the booster vaccines (AM-TT and conventional BCG), as compared with sham-vaccinated mice. All boosted groups, except for mice boosted with the AM-TT vaccine, responded with a proliferation of spleen T cells and gamma interferon production comparable to that induced by a single BCG vaccination.


Asunto(s)
Mananos/administración & dosificación , Toxoide Tetánico/administración & dosificación , Vacunas contra la Tuberculosis/administración & dosificación , Tuberculosis Pulmonar/prevención & control , Administración Intranasal , Animales , Vacuna BCG/administración & dosificación , Vacuna BCG/inmunología , Recuento de Colonia Microbiana/métodos , Femenino , Granuloma/inmunología , Granuloma/patología , Interferón gamma/inmunología , Pulmón/microbiología , Pulmón/patología , Mananos/inmunología , Ratones , Ratones Endogámicos C57BL , Polisacáridos Bacterianos/administración & dosificación , Polisacáridos Bacterianos/inmunología , Bazo/microbiología , Toxoide Tetánico/inmunología , Vacunas contra la Tuberculosis/inmunología , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/patología , Vacunación/métodos , Vacunas Conjugadas/administración & dosificación , Vacunas Conjugadas/inmunología
18.
Neuroscience ; 133(2): 571-81, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15885918

RESUMEN

This study aimed at investigating and influencing the basic electrophysiological functions and neuronal plasticity in the dentate gyrus in freely moving rats at several time-points after global ischemia. Although neuronal death was induced selectively in the cornu ammonis, subfield 1 (CA1)-region of the hippocampus, we found an additional loss of the population spike in the dentate gyrus after stimulation of the perforant path. Input/output-measurements revealed that as early as 1 day post-ischemia population spike generation in the granular cell layer is greatly decreased when compared with pre-ischemic values and to sham-operated animals, despite an apparently intact morphology of granular cells as evidenced by Nissl-staining. In contrast, the synaptic transmission (excitatory postsynaptic field potential) shows no significant difference when comparing values before and after ischemia and ischemic and sham-operated animals. Despite reduced output function, indicated by very small population spike amplitudes, long lasting potentiation can be induced 10 days after ischemia. Surprisingly, even "silent" populations of neurons, which appear selectively post-ischemia and do not show any evoked population spike, can be re-activated by tetanisation which is followed by a normal appearing long-term potentiation. However, this functional recovery seems to be partial and transient under current conditions: population spike-values do not reach pre-ischemic values and return to the low pre-tetanic baseline values the next day. Electrophysiological measurements ex vivo after ischemia indicate that the neuronal dysfunction in the dentate gyrus is not due to locally destroyed structures but that the activity of granular cells is merely suppressed only under in vivo conditions. In summary, global ischemia leaves a neighboring morphologically intact input area, functionally impaired. However, neuronal function can be partially regenerated by electrophysiological tetanic stimulation.


Asunto(s)
Giro Dentado/efectos de los fármacos , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Isquemia/fisiopatología , Toxina Tetánica/toxicidad , Análisis de Varianza , Animales , Muerte Celular/efectos de los fármacos , Muerte Celular/efectos de la radiación , Giro Dentado/patología , Giro Dentado/fisiopatología , Potenciales Postsinápticos Excitadores/fisiología , Isquemia/patología , Isquemia/terapia , Potenciación a Largo Plazo/efectos de los fármacos , Potenciación a Largo Plazo/fisiología , Masculino , Ratas , Ratas Wistar , Factores de Tiempo
19.
Sci Rep ; 5: 8217, 2015 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-25645753

RESUMEN

Vancomycin resistant enterococci (VRE) constitute a challenging problem in health care institutions worldwide. Novel methods to rapidly identify resistances are highly required to ensure an early start of tailored therapy and to prevent further spread of the bacteria. Here, a spectroscopy-based rapid test is presented that reveals resistances of enterococci towards vancomycin within 3.5 hours. Without any specific knowledge on the strain, VRE can be recognized with high accuracy in two different enterococci species. By means of dielectrophoresis, bacteria are directly captured from dilute suspensions, making sample preparation very easy. Raman spectroscopic analysis of the trapped bacteria over a time span of two hours in absence and presence of antibiotics reveals characteristic differences in the molecular response of sensitive as well as resistant Enterococcus faecalis and Enterococcus faecium. Furthermore, the spectroscopic fingerprints provide an indication on the mechanisms of induced resistance in VRE.


Asunto(s)
Enterococcus faecalis/efectos de los fármacos , Enterococcus faecium/efectos de los fármacos , Vancomicina/farmacología , Enterococcus faecalis/química , Enterococcus faecium/química , Espectrometría Raman , Factores de Tiempo , Resistencia a la Vancomicina
20.
J Bone Miner Res ; 14(8): 1387-93, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10457271

RESUMEN

In addition to the alendronate Osteoporosis Intervention Trial (FOSIT) core protocol 901-0A of 1908 enrolled patients, the use of peripheral quantitative computed tomography (pQCT) was explored for the assessment of response to therapy. Bone mineral and strength related parameters at two different sites at the distal radius were explored in a subset of the multicenter core study. One hundred and three patients were entered into the substudy and given either a daily dose of 10 mg of alendronate or placebo for 1 year. Measurements were done at months 0, 3, 6, and 12. Inclusion criteria were bone mineral density (BMD) measurements at the lumbar spine of -2 SD. The response to therapy was assessed by dual-energy X-ray absorptiometry in the lumbar spine and the hip, and by pQCT in the ultradistal and the shaft sites of the radius. In line with the FOSIT core study, alendronate increased BMD at the lumbar spine and the hip, and it decreased the serum biochemical markers of bone turnover. The substudy showed differences between the therapy and placebo group in trabecular bone density (8.4%, p = 0.095), in total density (6.8%, p = 0.009), and in the bone strength index (BSI) (15. 6 mm3, p = 0.037) at the ultradistal site due to treatment and no changes at the radius shaft. A significant correlation was observed between percentage changes from baseline in BMD of the lumbar spine, and in total density and bone strength at the ultradistal radius site in the treatment group, but not in the placebo group. Thus, the ultradistal radius site did respond to alendronate therapy. The increased bone density accompanied a significant gain in the BSI at the ultradistal site, a finding that might help explain the reduced wrist fractures in the alendronate Fracture Intervention Trial.


Asunto(s)
Alendronato/uso terapéutico , Densidad Ósea/efectos de los fármacos , Posmenopausia , Radio (Anatomía)/efectos de los fármacos , Resistencia a la Tracción/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad
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