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1.
HNO ; 2024 Oct 25.
Artículo en Alemán | MEDLINE | ID: mdl-39455446

RESUMEN

BACKGROUND: Planning of surgical procedures in patients suffering from oropharyngeal cancer requires appropriate imaging, particularly in consideration of the spatial relationship to the mandible. Resection of portions of the mandible (box, marginal, or segmental resection) is often necessary, while simultaneously avoiding overtreatment. Typically, a computed tomography (CT) scan is initially performed. However, the question arises of whether CT alone is adequate for reliable assessment of mandibular involvement. MATERIALS AND METHODS: A patient cohort of 25 individuals aged 44-79 years (mean 62 years) undergoing partial oropharyngeal resection with segmental mandibular resection was examined. The indication for segmental resection was based on the close relationship of the tumor to the mandible observed in imaging. Reconstruction was consistently carried out with a reconstruction plate and free or pedicled flaps. Preoperative radiological findings were compared with histopathology results after decalcification of the mandibular bone. RESULTS: Cortical tumor infiltration was observed in the mandible in 9 patients (36%). Preoperatively, clear bone infiltration had been identified in CT in only 2 of these 9 patients; in the remaining 7, only direct tumor contact with the mandible was evident. Magnetic resonance imaging (MRI) revealed bone infiltration in 1 of these 7 patients. DISCUSSION: Adhering to safety margins requires a radical surgical approach and reliable intraoperative frozen section analysis. However, at the bone level, intraoperative frozen section analysis is technically impractical due to the required decalcification. Only after decalcification can the entire specimen be assessed for tumor infiltration. In our cohort, a significant discrepancy in terms of bone infiltration was noted between preoperative imaging assessments and postoperative histopathology. CT preoperatively identified bone infiltration in only 8% of our patients. In two thirds of the specimens, no bone infiltration was evident after decalcification and histopathological processing, retrospectively indicating overtreatment by segmental resection; box or marginal resections may have been sufficient in these cases. Therefore, when tumors are adjacent to the bone in CT, MRI should also be performed preoperatively to more reliably detect bone infiltration.

2.
Mol Ther ; 25(9): 2093-2103, 2017 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-28760668

RESUMEN

Influenza A virus infection causes substantial morbidity and mortality in seasonal epidemic outbreaks, and more efficient treatments are urgently needed. Innate immune sensing of viral nucleic acids stimulates antiviral immunity, including cell-autonomous antiviral defense mechanisms that restrict viral replication. RNA oligonucleotide ligands that potently activate the cytoplasmic helicase retinoic-acid-inducible gene I (RIG-I) are promising candidates for the development of new antiviral therapies. Here, we demonstrate in an Mx1-expressing mouse model of influenza A virus infection that a single intravenous injection of low-dose RIG-I ligand 5'-triphosphate RNA (3pRNA) completely protected mice from a lethal challenge with influenza A virus for at least 7 days. Furthermore, systemic administration of 3pRNA rescued mice with pre-established fulminant influenza infection and prevented the fatal effects of a streptococcal superinfection. Type I interferon, but not interferon-λ, was required for the therapeutic effect. Our results suggest that the use of RIG-I activating oligonucleotide ligands has the clinical potential to confine influenza epidemics when a strain-specific vaccine is not yet available and to reduce lethality of influenza in severely infected patients.


Asunto(s)
Infecciones Bacterianas , Virus de la Influenza A , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Infecciones por Orthomyxoviridae/metabolismo , Infecciones por Orthomyxoviridae/virología , Sobreinfección , Animales , Quimiocina CXCL10/metabolismo , Virus de la Influenza A/inmunología , Interferón Tipo I/metabolismo , Ligandos , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Pulmón/virología , Proteínas de la Membrana/agonistas , Ratones , Ratones Transgénicos , Proteínas del Tejido Nervioso/agonistas , Oligonucleótidos/administración & dosificación , Oligonucleótidos/genética , Infecciones por Orthomyxoviridae/mortalidad , Sustancias Protectoras/administración & dosificación , ARN/administración & dosificación , ARN/genética , Receptores de Superficie Celular , Análisis de Supervivencia , Receptores Toll-Like/metabolismo
3.
Med Microbiol Immunol ; 206(2): 93-103, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27832373

RESUMEN

Human papillomaviruses (HPVs) are an acknowledged cause of a subset of oropharyngeal cancers, especially of tonsillar cancer. Similar to HPV, some human polyomaviruses (HPyVs), such as Merkel cell polyomavirus (MCPyV), have an oncogenic potential. Recently, several novel HPyVs have been discovered. The aim of our study was to determine viral DNA prevalence and viral DNA load of 13 different HPyVs in benign and malignant tonsillar tissue and to compare the data with those found for HPV. A total of 78 biopsies of palatine tonsils with a histologic diagnosis of non-malignant disease (chronic tonsillitis, tonsillar hyperplasia, n = 40) or tonsillar squamous cell carcinoma (n = 38) were included in the study. HPyV DNA prevalence and viral load were determined by virus-specific quantitative real-time PCRs. JCPyV (1/40, 2.5%) and WUPyV (3/40, 7.5%) were only found in non-malignant tonsillar tissue. HPyV7 and HPyV10 were only detected in one (2.6%) and seven (18.4%) of the 38 cancer biopsies, respectively. Both MCPyV (8/38, 21.1 vs. 4/40, 10.0%) and HPyV6 (2/38, 5.3 vs. 1/40, 2.5%) were found more frequently in cancer samples than in non-malignant tissue, but the differences were not significant. BKPyV, KIPyV, TSPyV, HPyV9, STLPyV, HPyV12 and NJPyV were not discovered in any of the samples. HPyV loads found in HPyV DNA-positive biopsies were very low with no difference between non-malignant and malignant samples (median load <0.0001 HPyV DNA copies per beta-globin gene copy, respectively). In contrast to HPyV, high-risk HPV types (HPV16/HPV18) were found significantly more frequently in tonsillar cancers than in non-malignant tonsillar tissue (17/38, 44.7 vs. 2/40, 5.0%, p < 0.001). Furthermore, high-risk HPV DNA loads were significantly higher in the cancer compared to the non-malignant samples (median load 11.861 vs. 7 × 10-6 HPV DNA copies per beta-globin gene copy, p = 0.012). While both HPV and HPyV may persist in tonsillar tissue, our data on HPyV DNA prevalence and load do not support a role of HPyV in tonsillar carcinogenesis, neither alone nor as co-infecting agents of HPV.


Asunto(s)
Tonsila Palatina/patología , Tonsila Palatina/virología , Papillomaviridae , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/virología , Infecciones por Polyomavirus/complicaciones , Infecciones por Polyomavirus/virología , Poliomavirus , Neoplasias Tonsilares/epidemiología , Neoplasias Tonsilares/etiología , Adulto , Anciano , Biopsia , Carcinoma , ADN Viral , Femenino , Humanos , Hiperplasia , Masculino , Persona de Mediana Edad , Papillomaviridae/genética , Poliomavirus/genética , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Tonsilares/diagnóstico , Infecciones Tumorales por Virus/complicaciones , Infecciones Tumorales por Virus/virología , Carga Viral , Adulto Joven
5.
Acta Neurochir (Wien) ; 153(12): 2361-3, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21984073

RESUMEN

Essential tremor (ET) is a neurological disorder that can be treated effectively by means of bilateral thalamic ventral intermediate nucleus (VIM) deep brain stimulation (DBS). We present a rare case of stimulation-dependent reversible ageusia that poses a therapeutic dilemma on the one hand and serves as an instructive example to elucidate the as yet incompletely defined gustatory pathways on the other. A 69-year-old patient with successful reduction of his disabling upper extremity ET experienced an almost complete but during stimulation cessation reversible ageusia under bilateral VIM DBS. An evaluation of diffusion tensor (DTI) neuroimaging studies was performed in order to detect effective electrode positions and volumes of activated tissue (VTA) in relation to the medial lemniscus (ML) and dentato-rubro-thalamic tract (DRT). Repeated subjective gustometry was conducted with differential manipulation of stimulation settings. This case report stresses the importance of fiber tracts for DBS surgery. Reconciled with previous findings in lesion cases, we assume the coexistence of decussating and non-decussating fibers in the gustatory tract combined with hemispheric dominance in the processing of gustatory information. A therapeutic option for this dilemma may be a patient-selectable stimulation program or bipolar stimulation establishing a smaller ovoid VTA.


Asunto(s)
Ageusia/fisiopatología , Estimulación Encefálica Profunda/efectos adversos , Estimulación Encefálica Profunda/métodos , Temblor Esencial/terapia , Complicaciones Intraoperatorias/fisiopatología , Núcleos Talámicos Ventrales/cirugía , Anciano , Ageusia/etiología , Temblor Esencial/fisiopatología , Humanos , Complicaciones Intraoperatorias/etiología , Masculino , Resultado del Tratamiento , Núcleos Talámicos Ventrales/anatomía & histología , Núcleos Talámicos Ventrales/fisiología
6.
PLoS One ; 14(7): e0218873, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31269055

RESUMEN

Saffold virus (SAFV) is classified into the Cardiovirus genus of the Picornaviridae family. Up to now, eleven genotypes have been identified however, their clinical significance remains unclear. Here, we investigated the presence of SAFV in asymptomatic patients admitted for adenoidectomy. A total of 70 adenoid tissue samples were collected from children with clinical symptoms caused by hypertrophy of adenoids but without symptoms of airway infection. Samples were investigated for SAFV by RT-nested PCR and sequence analysis. Eleven of 70 (15.7%) samples were positive for SAFV. Nasopharyngeal swabs were available from 45 children just before surgery. SAFV was rarely found and only in children with SAFV-positive adenoids 2/8. Our findings indicate that the presence of SAFV seems to be more frequent in adenoid tissue than expected. This could support the notion of a longer than previously anticipated persistence of SAFV nucleic acids in the respiratory tract and possibly a chronic infection. Further investigations are necessary to establish the role of SAFV infection in humans.


Asunto(s)
Tonsila Faríngea/virología , Cardiovirus/aislamiento & purificación , Hipertrofia/virología , Picornaviridae/aislamiento & purificación , Adenoidectomía , Tonsila Faríngea/patología , Cardiovirus/patogenicidad , Niño , Preescolar , Femenino , Genotipo , Humanos , Hipertrofia/patología , Masculino , Nasofaringe/virología , Picornaviridae/patogenicidad
7.
Ear Nose Throat J ; 84(3): 142-4, 147-9, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15871581

RESUMEN

Despite the wide variety of ossiculoplasty techniques that are available, success rates are limited. Current use indicates that surgeons prefer ceramic, autograft bone, and plastic pore prostheses. During the past decade, titanium prostheses have been used with great promise. Although their use is not widespread, satisfaction rates are high. An earlier study of ossiculoplasty showed that titanium prostheses were effective in reducing conductive hearing loss. To date, the surgical-handling attributes of titanium middle ear prostheses have not been assessed. We report the results of our survey of 32 otologic surgeons who used the open Tübingen titanium prosthesis for primary and revision ossiculoplasty during tympanoplasty in 400 patients at 12 academic and nonacademic otolaryngology clinics, most of them in Germany. Because the audiometric efficacy of titanium prostheses has been previously reported, our primary outcomes measures included ease of use with respect to the amount of time required to prepare the implants for placement and the surgeons' overall impression of the intraoperative handling characteristics of the implants, taking into consideration factors such as positioning, length adjustment, visibility, and the stability of the coupling. Surgeons also compared the properties of the titanium implant with those of gold, ceramic, and autograft implants that they had used in the past. Based on the results of 383 of the 400 ossiculoplasties, our survey revealed that the titanium implant was significantly superior to the others in all measured respects.


Asunto(s)
Prótesis Osicular , Reemplazo Osicular/métodos , Titanio , Adulto , Cerámica , Femenino , Estudios de Seguimiento , Alemania , Oro , Encuestas de Atención de la Salud , Humanos , Masculino , Ensayo de Materiales , Persona de Mediana Edad , Reemplazo Osicular/efectos adversos , Otolaringología/normas , Otolaringología/tendencias , Probabilidad , Diseño de Prótesis , Falla de Prótesis , Implantación de Prótesis , Medición de Riesgo , Encuestas y Cuestionarios , Trasplante Autólogo
9.
Laryngoscope ; 114(11): 2012-20, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15510033

RESUMEN

OBJECTIVES: The aim of the study was to evaluate the safety and feasibility of piezoelectric malleus vibration audiometer (MVA), which presents micromechanical vibrations to the umbo membranae tympani. STUDY DESIGN: Phase I study performed in a tertiary referral center (University Hospital). METHODS: The coupling rod of the MVA was moved slowly through the outer ear canal toward the eardrum with a micromanipulator. Coupling was completed when the rod tip touched the umbo membranae tympani. Basic audiologic measures of sound threshold obtained with direct stimulation of the malleus are presented. We used MANOVA (multivariate repeated measures ANOVA) to investigate the repeatability of MVA thresholds from one day to the other and when decoupling and retracting the coupling rod 2 mm off the umbo. We also selected the MANOVA to test for unwanted bone-conduction threshold shifts after MVA application. We assessed normality of the data by quantile-quantile plots of the residuals. RESULTS: Twenty-eight male and 10 female subjects with normal hearing, 22.2 to 34.6 years old (median age, 27.2 yr) underwent an examination. Thirty-six subjects underwent MVA, because 2 of the 38 subjects who volunteered for the study have not undergone the procedure due to the external auditory canal anatomy preventing application of the MVA. The results show that it is possible to safely and reliably measure thresholds of direct vibration of the ossicular chain. Using pure tone audiograms, no pure tone bone- and/or air-conduction threshold shifts occurred after the procedure. None of the subjects reported any other ear-related symptoms such as vertigo, tinnitus, or dizziness. Geometric mean vibratory displacements at threshold ranged from 0.55 nm at 250 Hz to 0.03 nm at 6 kHz. MANOVA demonstrated a repeatability of MVA thresholds. CONCLUSION: Malleus vibration audiometry will not allow exact linkage of actual implantable hearing aid. But the present study demonstrates that MVA can provide an audiometric tool for assessing ossicular function and integrity prior to implantation of an electronic hearing amplifier.


Asunto(s)
Audiometría , Umbral Auditivo , Osículos del Oído/fisiología , Oído , Adulto , Audiometría/efectos adversos , Audiometría/instrumentación , Diseño de Equipo , Estudios de Factibilidad , Femenino , Humanos , Masculino , Valores de Referencia , Reproducibilidad de los Resultados , Vibración
10.
Acta Otolaryngol ; 124(9): 1039-45, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15513547

RESUMEN

OBJECTIVE: To develop a procedure using a virtual reality (VR) environment that permitted us to simulate the preoperative fitting of an electronic implantable hearing device (IHD) and assess its implantability. MATERIAL AND METHODS: This was an experimental, prospective study based on VR simulations involving the pre- and postoperative comparison of the implantability of an IHD. The preoperative possibility of implanting an IHD in a VR environment was compared with the postoperative implantability of the device in the temporal bones of human cadavers and patients. Study groups were analyzed according to the criteria "VR implantation" and "real surgery" using contingency tables. RESULTS: A computer simulation method based on CT images was developed for the preoperative planning of the implantation. The VR simulation proved feasible in all cases (15 temporal bones and 24 patients). There was no significant difference between the process of implanting the IHD in patients or in the VR environment. These results indicate that VR-based test fittings of an IHD allow prediction of the implantability of an IHD prior to actual surgery. CONCLUSION: We have described the development of a novel VR procedure for predicting the implantability of hearing devices in otoneurosurgical applications. The VR procedure can be applied universally and may also be used for other parts of the body.


Asunto(s)
Implantación Coclear/métodos , Implantes Cocleares , Adulto , Simulación por Computador , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Cuidados Preoperatorios/métodos , Estudios Prospectivos , Hueso Temporal/diagnóstico por imagen , Hueso Temporal/cirugía , Tomografía Computarizada por Rayos X
11.
Antivir Ther ; 16(5): 751-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21817197

RESUMEN

BACKGROUND: Upper respiratory tract infection is a frequent cause of morbidity worldwide. Although the course of infection is usually mild, it is responsible for enormous social and economic costs. Immunostimulation with bacterial extracts consisting of ribosomal RNA and proteoglycans, such as Ribomunyl, was introduced into the clinic in the 1980s as a new treatment concept, but did not achieve widespread application. Ribomunyl has been proposed to activate innate immunity, but the contribution of its RNA content as well as its antiviral potential has not been studied. METHODS: Peripheral blood mononuclear cells from healthy donors and immune cells from adenoids were incubated with Ribomunyl either by itself or formulated in a complex with cationic polypeptides such as poly-l-arginine or protamine, and induction of cytokines was quantified by ELISA. RESULTS: Ribomunyl in complex with either poly-l-arginine or protamine, but not on its own, was able to strongly induce interferon-α (P<0.01) and interleukin-12 (P<0.01) in peripheral blood mononuclear cells, whereas induced tumour necrosis factor-α and interleukin-6 levels were independent of the formulation. Comparable results were obtained in immune cells from adenoids, suggesting efficacy also in virus-affected tissue. Cell sorting, RNase digests and selective receptor expression show that the RNA in Ribomunyl acts as an agonist of Toll-like receptor (TLR)7 and TLR8. CONCLUSIONS: Ribomunyl is, in principle, able to potently induce antiviral interferon-α and interleukin-12 via TLR7 and TLR8, respectively, but only when formulated in a complex with cationic polypeptides.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Antígenos Bacterianos/farmacología , Antivirales/farmacología , Poliaminas/química , Tonsila Faríngea/efectos de los fármacos , Adyuvantes Inmunológicos/metabolismo , Adyuvantes Inmunológicos/uso terapéutico , Antígenos Bacterianos/metabolismo , Antígenos Bacterianos/uso terapéutico , Antivirales/metabolismo , Antivirales/uso terapéutico , Arginina/química , Arginina/metabolismo , Citocinas/análisis , Citocinas/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Composición de Medicamentos , Células HEK293 , Humanos , Inmunización/métodos , Leucocitos Mononucleares/efectos de los fármacos , Terapia Molecular Dirigida , Poliaminas/metabolismo , Polielectrolitos , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/inmunología , Infecciones del Sistema Respiratorio/patología , Receptor Toll-Like 7/agonistas , Receptor Toll-Like 7/inmunología , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 8/agonistas , Receptor Toll-Like 8/inmunología , Receptor Toll-Like 8/metabolismo
12.
Fundam Clin Pharmacol ; 24(6): 729-39, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20030735

RESUMEN

Oxymetazoline and xylometazoline are both used as nasal mucosa decongesting α-adrenoceptor agonists during a common cold. However, it is largely unknown which of the six α-adrenoceptor subtypes are actually present in human nasal mucosa, which are activated by the two alpha-adrenoceptor agonists and to what extent. Therefore, mRNA expression in human nasal mucosa of the six α-adrenoceptor subtypes was studied. Furthermore, the affinity and potency of the imidazolines oxymetazoline and xylometazoline at these α-adrenoceptor subtypes were examined in transfected HEK293 cells. The rank order of mRNA levels of α-adrenoceptor subtypes in human nasal mucosa was: α(2A) > α(1A) ≥ α(2B) > α(1D) ≥ α(2C) >> α(1B) . Oxymetazoline and xylometazoline exhibited in radioligand competition studies higher affinities than the catecholamines adrenaline and noradrenaline at most α-adrenoceptor subtypes. Compared to xylometazoline, oxymetazoline exhibited a significantly higher affinity at α(1A) - but a lower affinity at α(2B) -adrenoceptors. In functional studies in which adrenoceptor-mediated Ca(2+) signals were measured, both, oxymetazoline and xylometazoline behaved at α(2B) -adrenoceptors as full agonists but oxymetazoline was significantly more potent than xylometazoline. Furthermore, oxymetazoline was also a partial agonist at α(1A) -adrenoceptors; however, its potency was relatively low and it was much lower than its affinity. The higher potency at α(2B) -adrenoceptors, i.e. at receptors highly expressed at the mRNA level in human nasal mucosa, could eventually explain why in nasal decongestants oxymetazoline can be used in lower concentrations than xylometazoline.


Asunto(s)
Agonistas alfa-Adrenérgicos/farmacología , Imidazoles/farmacología , Mucosa Nasal/efectos de los fármacos , Oximetazolina/farmacología , Adulto , Unión Competitiva , Femenino , Células HEK293 , Humanos , Masculino , Mucosa Nasal/metabolismo , ARN Mensajero/biosíntesis , Receptores Adrenérgicos alfa/biosíntesis , Receptores Adrenérgicos alfa/genética
13.
Exp Cell Res ; 303(2): 321-30, 2005 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-15652346

RESUMEN

Constitutive activation of the ras oncoprotein plays a critical role in cancer invasion and metastasis. Particularly, ras-related protease expression such as the serine protease urokinase plasminogen activator (u-PA) has been implicated in mediating cancer cell invasion. Previous studies have shown that ras-mediated u-PA expression is regulated through the mitogen- (MAPK) and stress-activated protein kinase (SAPK) signal transduction pathways extracellular signal-regulated kinase (ERK) and c-Jun-activating kinase (JNK). We therefore asked the question, if ras-related cell invasion might additionally require the third MAPK/SAPK signal transduction cascade, p38. Indeed, we found that ras induces invasion based on the activation of certain p38 protein kinase isoforms, in particular, p38alpha. Moreover, ras activation through transient or stable expression of a Ha-rasEJ mutant induced the expression of u-PA. This was found to be a consequence of an increase of u-PA m-RNA, which was paralleled by only a modest activation of the u-PA promoter. In conclusion, we provide evidence for the requirement of a novel ras-p38alpha-u-PA pathway for ras-dependent cellular invasion.


Asunto(s)
Genes ras , Proteínas Quinasas p38 Activadas por Mitógenos/fisiología , Animales , Secuencia de Bases , ADN/genética , Regulación de la Expresión Génica/efectos de los fármacos , Imidazoles/farmacología , Técnicas In Vitro , Isoenzimas/genética , Isoenzimas/fisiología , Sistema de Señalización de MAP Quinasas , Ratones , Células 3T3 NIH , Invasividad Neoplásica/genética , Invasividad Neoplásica/fisiopatología , Regiones Promotoras Genéticas/efectos de los fármacos , Piridinas/farmacología , Transfección , Activador de Plasminógeno de Tipo Uroquinasa/genética , Proteínas Quinasas p38 Activadas por Mitógenos/genética
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