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2.
Eur J Neurosci ; 40(3): 2528-40, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24891292

RESUMEN

To serve as a robust internal circadian clock, the cell-autonomous molecular and electrophysiological activities of the individual neurons of the mammalian suprachiasmatic nucleus (SCN) are coordinated in time and neuroanatomical space. Although the contributions of the chemical and electrical interconnections between neurons are essential to this circuit-level orchestration, the features upon which they operate to confer robustness to the ensemble signal are not known. To address this, we applied several methods to deconstruct the interactions between the spatial and temporal organisation of circadian oscillations in organotypic slices from mice with circadian abnormalities. We studied the SCN of mice lacking Cryptochrome genes (Cry1 and Cry2), which are essential for cell-autonomous oscillation, and the SCN of mice lacking the vasoactive intestinal peptide receptor 2 (VPAC2-null), which is necessary for circuit-level integration, in order to map biological mechanisms to the revealed oscillatory features. The SCN of wild-type mice showed a strong link between the temporal rhythm of the bioluminescence profiles of PER2::LUC and regularly repeated spatially organised oscillation. The Cry-null SCN had stable spatial organisation but lacked temporal organisation, whereas in VPAC2-null SCN some specimens exhibited temporal organisation in the absence of spatial organisation. The results indicated that spatial and temporal organisation were separable, that they may have different mechanistic origins (cell-autonomous vs. interneuronal signaling) and that both were necessary to maintain robust and organised circadian rhythms throughout the SCN. This study therefore provided evidence that the coherent emergent properties of the neuronal circuitry, revealed in the spatially organised clusters, were essential to the pacemaking function of the SCN.


Asunto(s)
Relojes Circadianos/fisiología , Ritmo Circadiano/fisiología , Criptocromos/fisiología , Receptores de Tipo II del Péptido Intestinal Vasoactivo/fisiología , Núcleo Supraquiasmático/fisiología , Animales , Relojes Circadianos/genética , Ritmo Circadiano/genética , Criptocromos/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Red Nerviosa/fisiología , Receptores de Tipo II del Péptido Intestinal Vasoactivo/genética
4.
Nuklearmedizin ; 50(3): 101-6, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21165538

RESUMEN

UNLABELLED: FDG-PET/CT is increasingly used in staging of lung cancer as single "one stop shop" method. AIM, PATIENTS, METHODS: We prospectively included 104 neurological asymptomatic patients (65 years, 26% women) with primary diagnosis of lung cancer. In all patients PET/CT including cerebral imaging and cerebral MRI were performed. RESULTS: Diagnosis of brain metastases (BM) was made by PET/CT in 8 patients only (7.7%), by MRI in 22 (21.2%). In 80 patients both PET/CT and MRI showed no BM. In 6 patients (5.8%) BM were detectable on PET/CT as well as on MRI. Exclusive diagnosis of BM by MRI with negative finding on PET/CT was present in 16 patients (15.4%). 2 patients (1.9%) had findings typical for BM on PET/CT but were negative on MRI. With MRI overall 100 BM were detected, with PET/CT only 17 BM (p < 0.01). For the diagnosis of BM PET/CT showed a sensitivity of 27.3%, specificity of 97.6%, positive predictive value of 75% and negative predictive value of 83.3%. BM diameter on PET/CT and MRI were consistent in 43%, in 57% BM were measured larger on MRI. DISCUSSION: Compared to the gold standard of MRI for cerebral staging a considerable number of patients are falsely diagnosed as free from BM by PET/CT. MRI is more accurate than PET/CT for detecting multiple and smaller BM. CONCLUSION: In patients with a curative option MRI should be performed additionally to PET/CT for definitive exclusion of brain metastases.


Asunto(s)
Neoplasias Encefálicas/epidemiología , Neoplasias Encefálicas/secundario , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiología , Imagen por Resonancia Magnética/estadística & datos numéricos , Tomografía de Emisión de Positrones/estadística & datos numéricos , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/diagnóstico , Carcinoma/diagnóstico , Carcinoma/epidemiología , Carcinoma/secundario , Femenino , Fluorodesoxiglucosa F18 , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Prevalencia , Radiofármacos , Reproducibilidad de los Resultados , Medición de Riesgo , Factores de Riesgo , Sensibilidad y Especificidad
5.
Z Gastroenterol ; 48(11): 1301-4, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21043009

RESUMEN

Schwannomas are rare tumors, usually benign, originating from the nerve sheath, and found only infrequently in the retroperitoneal space. We report on a 67-year-old woman who was initially misdiagnosed and treated for a liver hydatid cyst. After incomplete resection and recurrence of the tumor, we were able to diagnose a large retroperitoneal schwannoma that completely displaced the liver to the left abdomen. The patient underwent surgical resection of the schwannoma; pathological evaluation revealed a cystic tumor measuring 18.5 × 18 × 12.5 cm, with tumor cells staining strongly positive for S-100. Retroperitoneal schwannomas may mimic cystic hepatic tumors and should, therefore, be considered as a differential diagnosis in such cases. We describe the diagnostic modalities and difficulties in the approach of a cystic liver tumor.


Asunto(s)
Neurilemoma/patología , Neurilemoma/cirugía , Neoplasias Retroperitoneales/patología , Neoplasias Retroperitoneales/cirugía , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Hepáticas/patología , Resultado del Tratamiento
6.
Denisia ; 29: 383-406, 2010 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-26985170

RESUMEN

A larval key of the Drusinae of Central Europe and the dinaric western Balkan is presented. Phylogeographic relationships are discussed in the light of molecular genetics, feeding ecology and larval morphology.

8.
Ultraschall Med ; 31(1): 31-6, 2010 Feb.
Artículo en Inglés, Alemán | MEDLINE | ID: mdl-19266425

RESUMEN

PURPOSE: The objective of the present study is to compare the utility of extended field-of-view ultrasonography and conventional B-mode ultrasonography for determining liver size. MATERIALS AND METHODS: The liver size in the medioclavicular line (MCL) was determined in 104 inpatients (females: n = 47; males: n = 57) using both ultrasound methods (Philips HDI 5000). The liver size measured in computed tomography (CT; MX 8000 IDT, Philips) served as the gold standard. The body mass index (BMI), ultrasound scanning conditions, and hepatomegaly identified by CT were evaluated as possible factors affecting the measurement accuracy of the sonographic methods. RESULTS: The standard deviation of the differences between the measured pairs of values shows less dispersion in B-mode ultrasonography (18.7 mm) than panorama ultrasonography (20.8 mm). The mean value of differences between the measured pairs (bias) in the ultrasonographic methods compared to CT is considerably higher in panorama sonography (15.3 mm; SD = 20.8) than in B-mode ultrasonography (0.27 mm; SD = 18.7). A paired t-test of the mean values shows a significant difference between the ultrasonographic methods (p < 0.0001). In diagnosing or excluding hepatomegaly, B-mode sonography is consistent with CT findings in 84 (80.8 %) of 104 patients and panorama ultrasonography is consistent with CT findings in 77 (74.0 %) of 104 patients. Ultrasonographic methods show moderate agreement with each other (Kappa = 0.4265). Higher BMI and limited scanning conditions lead to an increase in the mean difference of measured pairs of values (bias) as well as to an increase in standard deviation of the differences (dispersion). CONCLUSION: The determination of liver size in the medioclavicular line using panorama ultrasonography often leads to the false-positive diagnosis of hepatomegaly. Therefore, the method should not be recommended for routine diagnostic scans. In cases of significant hepatomegaly, however, panorama ultrasonography offers superior visualization compared to conventional B-mode ultrasonography.


Asunto(s)
Hepatomegalia/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Hígado/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Ultrasonografía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Valores de Referencia , Sensibilidad y Especificidad , Adulto Joven
9.
Mol Ecol ; 18(24): 5180-94, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19878453

RESUMEN

In ant-plant protection mutualisms, plants provide nesting space and nutrition to defending ants. Several plant-ants are polygynous. Possessing more than one queen per colony can reduce nestmate relatedness and consequently the inclusive fitness of workers. Here, we investigated the colony structure of the obligate acacia-ant Pseudomyrmex peperi, which competes for nesting space with several congeneric and sympatric species. Pseudomyrmex peperi had a lower colony founding success than its congeners and thus, appears to be competitively inferior during the early stages of colony development. Aggression assays showed that P. peperi establishes distinct, but highly polygynous supercolonies, which can inhabit large clusters of host trees. Analysing queens, workers, males and virgin queens from two supercolonies with eight polymorphic microsatellite markers revealed a maximum of three alleles per locus within a colony and, thus, high relatedness among nestmates. Colonies had probably been founded by one singly mated queen and supercolonies resulted from intranidal mating among colony-derived males and daughter queens. This strategy allows colonies to grow by budding and to occupy individual plant clusters for time spans that are longer than an individual queen's life. Ancestral states reconstruction indicated that polygyny represents the derived state within obligate acacia-ants. We suggest that the extreme polygyny of Pseudomyrmex peperi, which is achieved by intranidal mating and thereby maintains high nestmate relatedness, might play an important role for species coexistence in a dynamic and competitive habitat.


Asunto(s)
Hormigas/genética , Variación Genética , Genética de Población , Conducta Sexual Animal , Agresión , Alelos , Animales , Conducta Competitiva , Evolución Molecular , Femenino , Masculino , México , Repeticiones de Microsatélite , Filogenia , Análisis de Secuencia de ADN
11.
Ann Hematol ; 88(10): 937-41, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19333601

RESUMEN

Bulky extramedullary hematopoiesis, usually detected in the thorax by imaging techniques, is a well-known complication in many types of congenital anemias. Here, we describe 12 cases of congenital dyserythropoietic anemia with extramedullary hematopoiesis which was always located in the paravertebral space of the thoracic spine and in other paraspinal regions in a few cases. All bulks were originally detected in chest radiographs and confirmed by imaging techniques such as computed tomography and/or magnetic resonance imaging. In some cases, thoracotomy was performed for suspected malignancy. Although the true prevalence is not known, paravertebral masses in patients with CDA of any type are not uncommon and should be the first differential diagnosis considered when masses adjacent to the spine are detected in this disorder.


Asunto(s)
Anemia Diseritropoyética Congénita/complicaciones , Hematopoyesis Extramedular , Adolescente , Adulto , Anciano , Anemia Diseritropoyética Congénita/patología , Recolección de Datos , Diagnóstico Diferencial , Diagnóstico por Imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Columna Vertebral/patología , Vértebras Torácicas/patología
12.
Eur Radiol ; 19(6): 1379-86, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19184036

RESUMEN

The purposes of this study was to provide a retrospective comparison of semiquantitatively measured bowel wall vascularity by power Doppler sonography, endoscopic-histopathological biopsy findings, and disease activity in patients with confirmed Crohn's disease. Thirty-two out of 1,332 patients with histologically confirmed Crohn's disease (18 female, 14 male; mean age 38.8 years) met the inclusion criteria: ileocolonoscopy with biopsy and power Doppler sonographic determination of bowel wall vascularity with assessment of disease activity within a period of 5 days. Sonographic determination of bowel wall vascularity was based on a semiquantitative score. Endoscopic bowel wall biopsy specimens were assessed using a self-developed inflammation score and the disease activity was calculated using Crohn's disease activity index (CDAI). A significant association (p < 0.05) was shown for results of histology and bowel wall vascularity in the terminal ileum (kappa = 0.66; sensitivity 95%; specificity 69%). There was no observed association between CDAI and histology, although there was an association between CDAI and bowel wall vascularity (sensitivity 82%). Increased bowel wall vascularity in the terminal ileum measured by power Doppler ultrasound reflects inflammatory activity in histologically examined bowel wall. Power Doppler ultrasound may be able to monitor activity changes of the bowel wall determined by pharmaceutical treatment.


Asunto(s)
Enfermedad de Crohn/diagnóstico por imagen , Enfermedad de Crohn/patología , Intestinos/diagnóstico por imagen , Intestinos/patología , Neovascularización Patológica/diagnóstico por imagen , Neovascularización Patológica/patología , Adolescente , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ultrasonografía , Adulto Joven
13.
Zootaxa ; 2031: 53-62, 2009 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-27069350

RESUMEN

This paper presents a description of the hitherto unknown larvae of Drusus franzi Schmid 1956, and Drusus alpinus (Meyer-Dür 1875). Information on the morphological and genetic identification of both species is given, and the most important diagnostic features are illustrated. Their systematic position within the genus Drusus is affirmed and zoogeographical and ecological notes are added.

15.
Nuklearmedizin ; 46(6): 239-43, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18084678

RESUMEN

UNLABELLED: AIM of this study was to investigate, how often TNM staging is changed in patients with malignant pleural mesothelioma (MPM) by the application of integrated PET-CT compared to computed tomography alone and how often these changes are clinically relevant. PATIENTS, METHODS: We studied 17 patients (68 +/- 6 years, 8 women) with MPM. Integrated PET-CT scan and histological confirmation were performed in all patients. RESULTS: Final histological diagnosis confirmed 9 epithelial type, 2 sarcomatoid type and 6 biphasic type MPM. Mean standardized uptake value (SUV) was 5.9 +/- 1.9 in epithelial MPM and 15.1 +/- 10.2 in sarcomatoid MPM. CT and PET-CT revealed discordances in 8/17 (47%) patients in TNM classification with 4/8 (50%) being clinically relevant. PET-CT led to downstaging in 5 (29%) and upstaging in 3 (18%) patients. Mean survival time tended to be higher in the subgroup of patients with lower mean SUV. CONCLUSIONS: PET-CT seems to be a valuable tool in staging of MPM and leads to discordant findings in almost every second patient compared to CT alone. In many cases these differences are clinically relevant and have therapeutic consequences.


Asunto(s)
Fluorodesoxiglucosa F18 , Mesotelioma/diagnóstico por imagen , Estadificación de Neoplasias/métodos , Neoplasias Pleurales/diagnóstico por imagen , Radiofármacos , Anciano , Femenino , Humanos , Masculino , Mesotelioma/patología , Persona de Mediana Edad , Neoplasias Pleurales/patología , Radiografía Torácica , Cintigrafía , Tomografía Computarizada por Rayos X
16.
Rofo ; 179(11): 1152-8, 2007 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-17948193

RESUMEN

PURPOSE: To assess interobserver agreement (IOA) in the diagnosis of pulmonary infiltrates on chest x-rays for patients with community-acquired pneumonia (CAP). MATERIALS AND METHODS: From 7/2002 to 12/2005, 806 adults with CAP were included in the multicenter study "CAPNETZ" (7 hospitals). Inclusion criteria were clinical signs of pneumonia and pulmonary opacification on chest x-rays. Each x-ray was reevaluated by two radiologists from the university hospital in consensus reading against the interpreter at the referring hospital in regard to: presence of infiltrate (yes/no/equivocal), transparency (50%), localization, and pattern of infiltrates (alveolar/interstitial). The following parameters were documented: digital or film radiography, hospitalization, fever, findings of auscultation, microbiological findings. RESULTS: The overall IOA concerning the detection of infiltrates was 77.7% (n=626; CI 0.75-0.81), the infiltrates were not verified in 16.4% (n=132) by the referring radiologist with equivocal findings in 5.9% (n=48). The IOA of the different clinical centers varied between 63.2% (n=38, CI 0.48-0.78) and 92.3% (n=65, CI 0.86-0.99). The IOA for the diagnosis of infiltrates was significantly higher for inpatients with 82.6% (n=546; CI 0.80-0.85) than for outpatients with 55.2 % (n=80; CI 0.47-0.63), p<0.0001. The IOA of infiltrates with a transparency >50% was 95.1% (n=215; CI 0.92-0.98) versus 80.4% (n=403; CI 0.77-0.84) for infiltrates with a transparency >50% (p<0.0001). In patients with positive auscultation, the IOA was higher (p=0,034). Chest x-rays of patients with antibiotic therapy or an alveolar infiltrate showed more equivocal findings compared to patients without these features. CONCLUSION: There is considerable interobserver variability in the diagnosis of pulmonary infiltrates on chest radiographs. The IOA is higher in more opaque infiltrates, positive auscultation and inpatients.


Asunto(s)
Infecciones Comunitarias Adquiridas/diagnóstico por imagen , Neumonía Bacteriana/diagnóstico por imagen , Radiografía Torácica , Adulto , Infecciones Comunitarias Adquiridas/epidemiología , Alemania/epidemiología , Humanos , Variaciones Dependientes del Observador , Neumonía Bacteriana/clasificación , Neumonía Bacteriana/epidemiología
17.
Br J Radiol ; 80(956): e173-5, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17762050

RESUMEN

We report the case of a 55-year-old male patient who presented with non-specific pulmonary symptoms (cough, haemoptysis, fever up to 39 degrees C, night sweats and weight loss). After empirical antibiotic therapy prescribed by his primary care physician, the patient showed no improvement in symptoms. Laboratory findings were: elevated C-reactive protein and C-ANCA, leukocytosis and thrombocytosis, and anaemia. Chest radiography showed disseminated nodules bilaterally. On multidetector-row computed tomography (MDCT), the bronchial walls showed a significant thickening and extensive peribronchiolar consolidations. Bronchoscopy revealed diffuse erythema of the tracheobronchial mucosa with diffusely scattered white plaques. Histopathology described a multifocal ulcerative bronchitis with underlying chronic bronchitis. These findings in combination with the laboratory data lead to the diagnosis of Wegener's granulomatosis. Consequently, we started with an immunosuppressive therapy. Chest radiography after 10 days showed marked resolution of the infiltrates. Within 1 month, the patient became asymptomatic.


Asunto(s)
Bronquios/patología , Enfermedades Bronquiales/diagnóstico por imagen , Granulomatosis con Poliangitis/diagnóstico por imagen , Úlcera/diagnóstico por imagen , Biopsia/métodos , Enfermedades Bronquiales/complicaciones , Enfermedades Bronquiales/patología , Granulomatosis con Poliangitis/complicaciones , Granulomatosis con Poliangitis/patología , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Úlcera/complicaciones , Úlcera/patología
20.
Eur J Neurol ; 14(5): 548-55, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17437615

RESUMEN

The aim of the study was to assess neuroimaging patterns of cerebral aspergillosis with magnetic resonance imaging (1.5 T). The clinical and imaging data of nine patients were reviewed. Patients were included in the study if the diagnosis of aspergillosis was confirmed by either biopsy, autopsy, aspergillus antigen determination and/or neuroradiological and clinical response to specific treatment. Four patients had single or multiple abscesses presenting as ring-enhancing lesions on T1-weighted images, hypointensity of the ring on T2-weighted MR images and low to high signal intensity on diffusion-weighted imaging. Four patients had single or multiple infarctions affecting all compartments of the brain with hyperintensities on T2-weighted images in three of four patients, irregular parenchymal contrast enhancement in all patients and hemorrhagic transformation of the infarcted parenchyma in one patient. Diffusion-weighted images were positive in all ischemic areas. One patient with paranasal sinusitis developed a mycotic aneurysm of the internal carotid artery. Cerebral aspergillosis presents three principal neuroimaging findings: areas consistent with infarction; ring lesions consistent with abscess formation following infarction; and dural or vascular infiltration originating from paranasal sinusitis or orbital infiltration. Recognition of these patterns in cerebral aspergillosis may lead to more timely and effective diagnosis and treatment.


Asunto(s)
Encéfalo/microbiología , Encéfalo/patología , Huésped Inmunocomprometido/inmunología , Neuroaspergilosis/patología , Adulto , Anciano , Encéfalo/fisiopatología , Absceso Encefálico/microbiología , Absceso Encefálico/patología , Absceso Encefálico/fisiopatología , Estudios de Casos y Controles , Infarto Cerebral/microbiología , Infarto Cerebral/patología , Infarto Cerebral/fisiopatología , Femenino , Humanos , Inmunosupresores/efectos adversos , Leucemia/tratamiento farmacológico , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mortalidad , Neuroaspergilosis/mortalidad , Neuroaspergilosis/fisiopatología , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Tasa de Supervivencia
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