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1.
J Acoust Soc Am ; 154(5): 2937-2949, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37938046

RESUMO

There are substantial interspecific differences in the morphology of the ears of the more than 34 000 living fish species. However, almost nothing is known about the functional significance of these differences. One reason is that most comparative studies have been conducted on shallow-water species with far less focus on the numerous species that inhabit the depths of the oceans. Thus, to get a better sense of ear diversity in fishes and its potential role in hearing, this study focuses on the saccule and lagena, the primary auditory end organs, in six species of the family Macrouridae (rattails), a large group of fishes that typically inhabit depths from 1000 to 4000 m. The inner ears and, particularly, the saccules and lagenae in these species are large with the saccule resembling that of other Gadiformes. The lagenae of all macrourids studied here have serrated edge otoliths and highly diverse hair cell ciliary bundle shapes. The differences found in the inner ear anatomy of macrourids likely reflect the sensory advantages in different habitats that are related to the benefits and constraints at different depths, the fish's particular lifestyle, and the trade-off among different sensory systems.


Assuntos
Peixes , Gadiformes , Animais , Sáculo e Utrículo , Audição , Membrana dos Otólitos
2.
J Neurosurg Case Lessons ; 3(6)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36130555

RESUMO

BACKGROUND: The transsphenoidal approach to the skull base has enjoyed increasing popularity for surgery of the sellar region avoiding brain retraction and causing few severe complications. While vitally important vessels in this region show a high degree of variability, some anatomical variants might be involved in characteristic complications. OBSERVATIONS: We present the case of a 40-year-old female patient with acromegaly due to a pituitary adenoma that was transsphenoidally operated. Postoperatively, the patient presented with bilateral unresponsive mydriasis, loss of consciousness and tetraparesis. An MRI showed well-circumscribed bilateral paramedian thalamic infarctions which indicated a rare Percheron-like artery. At 2-year follow-up examination the patient was dramatically improved but with a profound impact on her ability to interact with the world. LESSONS: The basilar artery or perforators might be injured during dissection of suprasellar lesions. This vascular territory is essential to interaction of the brain with the outside world. We conclude that we will approach future suprasellar adenomas strictly intracapsularly.

3.
Radiologie (Heidelb) ; 62(7): 556-562, 2022 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-35737001

RESUMO

BACKGROUND: Chronic type B aortic dissection requires optimal medical therapy. However, secondary complications like organ or extremity malperfusion or development of aneurysmal dilatation require interventional therapy. OBJECTIVES: Presentation of different endovascular treatment options for complications of chronic type B aortic dissection. MATERIALS AND METHODS: Analysis of current literature with regard to indications, techniques, results, and differential indications of interventional techniques for the treatment of chronic type B aortic dissection complications. RESULTS: Endovascular implantation of an aortic stent graft is interventional standard therapy for treatment of aneurysmal dilatation of the aorta following type B dissection. Technical problems are the proximal and distal landing zones and the treatment of persistent flow in the false lumen. CONCLUSION: Endovascular treatment of chronic complicated type B aortic dissection is increasingly used compared to open surgical treatment because not only are more complex stent grafts (fenestrated and branched devices) available but also because of newly developed techniques for effective occlusion of flow in the false lumen (e.g., candy plug).


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Dissecção Aórtica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular , Humanos , Desenho de Prótese , Resultado do Tratamento
4.
Pediatr Blood Cancer ; 66(7): e27752, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30977593

RESUMO

BACKGROUND: Epstein-Barr virus (EBV) is linked to a variety of malignancies; most endemic Burkitt lymphoma (BL) harbor EBV, whereas only a subset of the cases of sporadic BL is EBV positive. PROCEDURE: We retrospectively determined the herpesvirus seroprevalence at the time of diagnosis in pediatric non-Hodgkin lymphoma (NHL) patients enrolled in NHL-BFM (Berlin-Frankfurt-Muenster) studies. We accessed the seroepidemiological data from 1147 patients that became available during 1990-2007. We included the records from patients 6 months to 18 years of age with BL, T-cell lymphoblastic lymphoma (T-LBL), lymphoblastic precursor B-cell lymphoma (pB-LBL), diffuse large B-cell lymphoma (DLBCL), or anaplastic large cell lymphoma (ALCL). RESULTS: EBV seropositivity was significantly more frequent in patients with BL than in those with T-LBL. EBV was more prevalent in patients younger than 6 years of age and in patients with BL than in those with non-BL or T-LBL. Event-free survival was significantly lower in varicella-zoster-seronegative patients, but there was no indication of an association to complications due to varicella zoster infection. We found no associations between herpes simplex virus, varicella zoster virus, or human cytomegalovirus seroprevalence and the pediatric Central European NHL cases. CONCLUSION: Early EBV exposure may increase the risk of BL in Central Europe. A higher involvement of EBV in European BL than originally reported appears at least probable. Our data support the thesis that the distinction between endemic and sporadic BL is artificial and should be replaced by the differentiation between EBV-positive and EBV-negative BL.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Linfoma não Hodgkin , Adolescente , Fatores Etários , Criança , Pré-Escolar , Infecções por Citomegalovirus/mortalidade , Infecções por Citomegalovirus/virologia , Infecções por Vírus Epstein-Barr/mortalidade , Infecções por Vírus Epstein-Barr/virologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Lactente , Linfoma não Hodgkin/mortalidade , Linfoma não Hodgkin/virologia , Masculino , Prevalência , Estudos Retrospectivos , Fatores de Risco , Estudos Soroepidemiológicos
5.
Sci Rep ; 6: 39395, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27996027

RESUMO

Most deep-sea fish have a single visual pigment maximally sensitive at short wavelengths, approximately matching the spectrum of both downwelling sunlight and bioluminescence. However, Malcosteus niger produces far-red bioluminescence and its longwave retinal sensitivity is enhanced by red-shifted visual pigments, a longwave reflecting tapetum and, uniquely, a bacteriochlorophyll-derived photosensitizer. The origin of the photosensitizer, however, remains unclear. We investigated whether the bacteriochlorophyll was produced by endosymbiotic bacteria within unusual structures adjacent to the photoreceptors that had previously been described in this species. However, microscopy, elemental analysis and SYTOX green staining provided no evidence for such localised retinal bacteria, instead the photosensitizer was shown to be distributed throughout the retina. Furthermore, comparison of mRNA from the retina of Malacosteus to that of the closely related Pachystomias microdon (which does not contain a bacterichlorophyll-derived photosensitzer) revealed no genes of bacterial origin that were specifically up-regulated in Malacosteus. Instead up-regulated Malacosteus genes were associated with photosensitivity and may relate to its unique visual ecology and the chlorophyll-based visual system. We also suggest that the unusual longwave-reflecting, astaxanthin-based, tapetum of Malacosteus may protect the retina from the potential cytotoxicity of such a system.


Assuntos
Bacterioclorofilas/metabolismo , Peixes/metabolismo , Perciformes/metabolismo , Fármacos Fotossensibilizantes/metabolismo , Retina/metabolismo , Animais , Clorofila/metabolismo , Luz , RNA Mensageiro/metabolismo , Pigmentos da Retina/metabolismo , Regulação para Cima/fisiologia , Xantofilas/metabolismo
6.
J Exp Biol ; 218(Pt 18): 2826-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26206352

RESUMO

Using immunohistochemistry and western blot analysis, we demonstrate that melanopsin is localised in cells around the central pore of lateral line neuromasts in the African clawed frog, Xenopus laevis. Since melanopsin is a known photoreceptor pigment with diverse functions in vertebrates, we suggest that the lateral line of Xenopus laevis, which is primarily a mechanoreceptor, might also be light sensitive. Potential functions of such photosensitivity are discussed, including its role in mediating locomotor responses following dermal illumination.


Assuntos
Mecanorreceptores/metabolismo , Opsinas de Bastonetes/metabolismo , Xenopus laevis/fisiologia , Animais , Sistema da Linha Lateral/metabolismo , Luz
7.
Biol Cybern ; 108(5): 541-57, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25142940

RESUMO

The aim of this study was to obtain information on the axonal diameters of cortico-cortical fibres in the human brain, connecting distant regions of the same hemisphere via the white matter. Samples for electron microscopy were taken from the region of the superior longitudinal fascicle and from the transitional white matter between temporal and frontal lobe where the uncinate and inferior occipitofrontal fascicle merge. We measured the inner diameter of cross sections of myelinated axons. For comparison with data from the literature on the human corpus callosum, we also took samples from that region. For comparison with well-fixed material, we also included samples from corresponding regions of a monkey brain (Macaca mulatta). Fibre diameters in human brains ranged from 0.16 to 9 µm. Distributions of diameters were similar in the three systems of cortico-cortical fibres investigated, both in humans and the monkey, with most of the average values below 1 µm diameter and a small population of much thicker fibres. Within individual human brains, the averages were larger in the superior longitudinal fascicle than in the transitional zone between temporal and frontal lobe. An asymmetry between left and right could be found in one of the human brains, as well as in the monkey brain. A correlation was also found between the thickness of the myelin sheath and the inner axon diameter for axons whose calibre was greater than about 0.6 µm. The results are compared to white matter data in other mammals and are discussed with respect to conduction velocity, brain size, cognition, as well as diffusion weighted imaging studies.


Assuntos
Axônios/ultraestrutura , Córtex Cerebral/anatomia & histologia , Tomografia com Microscopia Eletrônica , Bainha de Mielina/ultraestrutura , Substância Branca/citologia , Idoso , Idoso de 80 Anos ou mais , Animais , Córtex Cerebral/ultraestrutura , Lateralidade Funcional , Humanos , Macaca mulatta , Masculino , Substância Branca/ultraestrutura
8.
Prog Retin Eye Res ; 38: 43-69, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24157316

RESUMO

This article presents a summary and critical review of what is known about the 'grouped retina', a peculiar type of retinal organization in fish in which groups of photoreceptor cell inner and outer segments are arranged in spatially separated bundles. In most but not all cases, these bundles are embedded in light-reflective cups that are formed by the retinal pigment epithelial cells. These cups constitute a specialized type of retinal tapetum (i.e., they are biological 'mirrors' that cause eye shine) and appear to be optimized for different purposes in different fishes. Generally, the large retinal pigment epithelial cells are filled with light-reflecting photonic crystals that consist of guanine, uric acid, or pteridine depending on species, and which ensure that the incoming light becomes directed onto the photoreceptor outer segments. This structural specialization has so far been found in representatives of 17 fish families; of note, not all members of a given family must possess a grouped retina, and the 17 families are not all closely related to each other. In many cases (e.g., in Osteoglossomorpha and Aulopiformes) the inner surface of the cup is formed by three to four layers of strikingly regularly shaped and spaced guanine platelets acting as an optical multilayer. It has been estimated that this provides an up to 10fold increase of the incident light intensity. In certain deep-sea fish (many Aulopiformes and the Polymixidae), small groups of rods are embedded in such 'parabolic mirrors'; most likely, this is an adaptation to the extremely low light intensities available in their habitat. Some of these fishes additionally possess similar tapetal cups that surround individual cones and, very likely, also serve as amplifiers of the weak incident light. In the Osteoglossomorpha, however, that inhabit the turbid water of rivers or streams, the structure of the cups is more complex and undergoes adaptation-dependent changes. At dim daylight, probably representing the usual environmental conditions of the fish, the outer segments of up to 30 cone cells are placed at the bottom of the cup where light intensity is maximized. Strikingly, however, a large number of rod receptor cells are positioned behind each mirroring cup. This peculiar arrangement (i) allows vision at deep red wavelenghts, (ii) matches the sensitivity of rod and cone photoreceptors, and (iii) facilitates the detection of low-contrast and color-mixed stimuli, within the dim, turbid habitat. Thus, for these fish the grouped retina appears to aid in reliable and quick detection of large, fast moving, biologically relevant stimuli such as predators. Overall, the grouped retina appears as a peculiar type of general retinal specialization in a variety of fish species that is adaptive in particular habitats such as turbid freshwater but also the deep-sea. The authors were prompted to write this review by working on the retina of Gnathonemus petersii; the data resulting from this work (Landsberger et al., 2008; Kreying et al., 2012) are included in the present review.


Assuntos
Peixes/anatomia & histologia , Visão Mesópica/fisiologia , Células Fotorreceptoras de Vertebrados/fisiologia , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/fisiologia , Percepção Visual/fisiologia , Animais , Luz
9.
J Comp Neurol ; 521(17): 4075-93, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23817965

RESUMO

The retina of the weakly electric fish Gnathonemus petersii is a so-called grouped retina where photoreceptors are bundled. These bundles are regarded as functional units and this type of retinal specialization is uniquely found in teleosts. To understand how this anatomical organization influences visual information processing we investigated the morphology and distribution of retinal ganglion cells (GCs) and the response properties of retinal afferents terminating in the major retinorecipient area, the optic tectum. GCs were classified based on their dendritic morphology (dendritic field diameters <90-100 µm: narrow-field GCs; 110-280 µm: widefield GCs; >280 µm: giant GCs). Within these classes subtypes were distinguished based on the ramification patterns of the dendrites in the sublaminae of the inner plexiform layer. Properties of presumed optic nerve terminals were investigated in the optic tectum using extracellular recordings. Physiological classes could be observed based on their response to visual stimuli (on; off; on-off, and fast units). Receptive field sizes and spatiotemporal properties were classified and the topographical representation of the visual space was mapped in the tectum. Gratings of low spatial frequencies were best responded to and followed up to high temporal frequencies (>30 Hz). Most of the recorded units were directionally selective. No evidence of distorted topographies in the tectum was found, i.e., no overrepresentation of the retina was seen in the tectum opticum. The grouped retina of G. petersii seems to be optimized for the detection of large, fast objects in an environment of low optical quality.


Assuntos
Peixe Elétrico/fisiologia , Células Ganglionares da Retina/fisiologia , Percepção Espacial/fisiologia , Colículos Superiores/fisiologia , Vias Visuais/fisiologia , Animais , Olho/citologia , Humanos , Camundongos , Ratos , Retina/citologia , Retina/fisiologia , Colículos Superiores/citologia , Vias Visuais/citologia
10.
Anat Rec (Hoboken) ; 296(7): 1064-82, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23625740

RESUMO

Inner ear structures are compared among three major genera of the deep-sea fish family Melamphaidae (bigscales and ridgeheads). Substantial interspecific variation is found in the saccular otoliths, including the presence of a unique otolithic "spur" in the genera Melamphaes and Poromitra. The variation in the saccular otolith is correlated with an increase in the number of hair bundle orientation groups on the sensory epithelia from the genera Scopelogadus to Poromitra to Melamphaes. The diverse structural variations found in the saccule may reflect the evolutionary history of these species. The sensory hair cell bundles in this family have the most variable shapes yet encountered in fish ears. In the saccule, most of the hair bundles are 15-20 µm high, an exceptional height for fish otolithic end organs. These bundles have large numbers of stereovilli, including some that reach the length of the kinocilium. In the utricle, the striolar region separates into two unusually shaped areas that have not been described in any other vertebrates. The brains in all species have a relatively small olfactory bulb and optic tectum, as well as an enlarged posterior cerebellar region that is likely to be involved in inner ear and lateral line (octavolateral) functions. Data from melamphaids support the hypothesis that specialized anatomical structures are found in the ears of some (if not most) deep-sea fishes, presumably enhancing their hearing sensitivity.


Assuntos
Orelha Interna/anatomia & histologia , Peixes/anatomia & histologia , Animais , Limiar Auditivo , Cerebelo/anatomia & histologia , Orelha Interna/fisiologia , Orelha Interna/ultraestrutura , Peixes/genética , Peixes/fisiologia , Células Ciliadas Vestibulares/ultraestrutura , Microscopia Eletrônica de Varredura , Bulbo Olfatório/anatomia & histologia , Membrana dos Otólitos/anatomia & histologia , Filogenia , Especificidade da Espécie , Estereocílios/ultraestrutura , Colículos Superiores/anatomia & histologia
11.
Expert Rev Clin Immunol ; 9(2): 139-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23390945

RESUMO

EBV, a gammaherpesvirus and the pathogenic agent for infectious mononucleosis, is also associated with a broad spectrum of lymphoid and epithelial malignancies in immunocompetent and immunosuppressed individuals. EBV-DNA-load measurement by PCR has been shown to be a potential tool for the diagnosis of these diseases, a prognostic factor of their outcome and a successful method to monitor immunosuppressed patients. Since the end of 2011, there is an international WHO standard reference for EBV quantification available; however, many questions still remain; for instance about the optimal amplified region of the EBV genome, or the best-used specimen for EBV detection. Additionally, the optimal specimen and amplified region may vary in different malignancies. In this article, the authors review the different methods to measure EBV load, focus on the best-used specimen for the different EBV-associated malignancies and discuss future requirements and opportunities for EBV-load measurement.


Assuntos
DNA Viral/análise , Infecções por Vírus Epstein-Barr/genética , Neoplasias/diagnóstico , Neoplasias/genética , Carga Viral/métodos , Animais , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4 , Humanos , Neoplasias/etiologia , Patologia Molecular , Reação em Cadeia da Polimerase , Guias de Prática Clínica como Assunto , Prognóstico , Organização Mundial da Saúde
12.
Heart Fail Rev ; 18(3): 307-16, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22648151

RESUMO

The epicardial halo delineates the heart shadow in fluoroscopy. To establish whether the sign is applicable to pericardiocentesis guidance, three investigators evaluated its intensity as absent = grade 0, indistinct = 0.5, clear = 1, intensive = 2 in posterior-anterior (PA) and lateral fluoroscopies recorded before pericardiocentesis or cardiac catheterization (Philips Integris-II BH3000). Three populations were studied: (a) 32 patients with pericardial effusion (PE group), 53.1 % males, aged 53.9 ± 13.9 years; (b) 14 patients with perimyocarditis (PM group), 64.3 % males, aged 51.6 ± 14.4 years; and (c) 46 coronary patients (CAD group), no PE, 95.6 % males, aged 67.3 ± 11.8 years. The intensity of the halo phenomenon was highest in patients with PE, lowest in patients with CAD, and intermediate in patients with PM (median sum of grades in PA/lateral view: 4/5 vs. 2/2.5 vs. 3/3, respectively) (p < 0.01). The halo phenomenon correlated well with HR and echocardiographic PE size in both angiographic views. The correlation with body mass index (BMI) and age was significant only in the lateral view and with PE volume only in the PA view. The sensitivity of the halo sign for PE was 84.1 % in PA and 92.0 % in lateral views. In 10/32 PE patients, the evaluation of the sign was repeated after PE drainage, revealing lower grades both in PA and in lateral views (p < 0.01). In conclusion, the epicardial halo sign is highly sensitive for the detection of a PE; it correlates well in at least one angiographic projection with the PE volume, HR, age, BMI, and the PE size in echocardiography and could be therefore applied as a safety guide for pericardiocentesis.


Assuntos
Doença da Artéria Coronariana , Fluoroscopia , Derrame Pericárdico , Pericardiocentese/métodos , Pericardite , Pericárdio/diagnóstico por imagem , Tecido Adiposo/patologia , Adulto , Fatores Etários , Idoso , Índice de Massa Corporal , Cateterismo Cardíaco/métodos , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/fisiopatologia , Ecocardiografia/métodos , Feminino , Fluoroscopia/métodos , Fluoroscopia/estatística & dados numéricos , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pericárdico/diagnóstico , Derrame Pericárdico/etiologia , Derrame Pericárdico/fisiopatologia , Pericardite/etiologia , Pericardite/fisiopatologia , Pericárdio/patologia , Sensibilidade e Especificidade , Resultado do Tratamento
13.
J Physiol Paris ; 107(1-2): 84-94, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22771549

RESUMO

Weakly electric fish orient, hunt and communicate by emitting electrical pulses, enabling them to discriminate objects, conspecifics and prey. In addition to the electrosensory modality - although dominating in importance in these fishes - other modalities, like vision, play important roles for survival. The visual system of Gnathonemus petersii, a member of the family mormyridae living in West African blackwater streams shows remarkable specializations: Cone photoreceptors are grouped in bundles within a light reflecting tapetum lucidum, while the rods are also bundled but located at the back within a light-scattering guanine layer. Such an organization does not improve light sensitivity nor does it provide high spatial resolution. Thus, the function of the grouped retinal arrangement for the visual performance of the fish remains unclear. Here we investigated the contrast sensitivity of the temporal transfer properties of the visual system of Gnathonemus. To do so, we analyzed visual evoked potentials in the optic tectum and tested the critical flicker fusion frequency in a behavioral paradigm. Results obtained in Gnathonemus are compared to results obtained with goldfish (Carassius auratus), revealing differences in the filter characteristics of their visual systems: While goldfish responds best to low frequencies, Gnathonemus responds best at higher frequencies. The visual system of goldfish shows characteristics of a low-pass filter while the visual system of Gnathonemus has characteristics of a band-pass filter. Furthermore we show that the visual system of Gnathonemus is more robust towards contrast reduction as compared to the goldfish. The grouped retina might enable Gnathonemus to see large, fast moving objects even under low contrast conditions. Due to the fact that the electric sense is a modality of limited range, it is tempting to speculate that the retinal specialization of Gnathonemus petersii might be advantageous for predator avoidance even when brightness differences are small.


Assuntos
Sensibilidades de Contraste/fisiologia , Peixe Elétrico/fisiologia , Potenciais Evocados Visuais/fisiologia , Retina/fisiologia , Vias Visuais/fisiologia , Animais , Comportamento de Escolha/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia , Vias Visuais/anatomia & histologia
14.
J Neurol Surg A Cent Eur Neurosurg ; 74 Suppl 1: e70-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23015296

RESUMO

INTRODUCTION: We report the case of a 17-year-old girl with an indolent, smooth swelling of the left cranial vault that had been developing for 2 months. Complete surgical excision was performed and the defect was closed using artificial bone cement. The integrity of the dura mater was conserved and the patient recovered without neurological deficit. Magnetic resonance imaging (MRI) controls 6 and 18 months after the operation did not find signs of recurrence. RESULTS: The lesion consisted of an elastic bone shell containing bony trabeculae with soft brown-greyish tissue and posthemorrhagic dark fluid. Histological assessment found CD68 positive multinucleated giant cells in a highly cellular fibroblastic matrix surrounding bony lamellar structures, without signs of inflammation or malignancy. Hyperparathyroidism was ruled out by normal serum values for parathyroid hormone, calcium, phosphate, and alkaline phosphatase. Histologically, first diagnosis was giant cell reparative granuloma and reference pathology disclosed aneurysmal bone cyst. CONCLUSIONS: The solid variant of aneurysmal bone cyst and the giant cell reparative granuloma can be histologically indistinguishable. Both lesions are only rarely encountered in cranial bones and most published cases affected the cranial base or the jaw, mainly in children or young adults. From a clinical point of view, classification into "outward" lesions (osteolysis of external parts of the vault with preservation of internal tabula) and "inward" lesions (intracranial multicystic lesions with raise of intracranial pressure) has been proposed. Three phases of development can be identified, and spontaneous involution has been described. Both entities are benign, but because in several cases an underlying malignant disease has been found, complete resection and regular follow-up by MRI are recommended.


Assuntos
Cistos Ósseos Aneurismáticos/patologia , Cistos Ósseos Aneurismáticos/cirurgia , Procedimentos Neurocirúrgicos/métodos , Osso Parietal/patologia , Osso Parietal/cirurgia , Adolescente , Cistos Ósseos Aneurismáticos/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Exame Neurológico , Osteotomia , Osso Parietal/diagnóstico por imagem , Radiografia , Crânio/patologia , Trepanação
15.
Science ; 336(6089): 1700-3, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-22745429

RESUMO

Despite their diversity, vertebrate retinae are specialized to maximize either photon catch or visual acuity. Here, we describe a functional type that is optimized for neither purpose. In the retina of the elephantnose fish (Gnathonemus petersii), cone photoreceptors are grouped together within reflecting, photonic crystal-lined cups acting as macroreceptors, but rod photoreceptors are positioned behind these reflectors. This unusual arrangement matches rod and cone sensitivity for detecting color-mixed stimuli, whereas the photoreceptor grouping renders the fish insensitive to spatial noise; together, this enables more reliable flight reactions in the fish's dim and turbid habitat as compared with fish lacking this retinal specialization.


Assuntos
Peixes/fisiologia , Retina/fisiologia , Visão Ocular , Animais , Peixes/anatomia & histologia , Carpa Dourada , Luz , Células Fotorreceptoras de Vertebrados/fisiologia , Células Fotorreceptoras de Vertebrados/ultraestrutura , Comportamento Predatório , Retina/anatomia & histologia , Retina/ultraestrutura
16.
Behav Brain Res ; 232(1): 148-58, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22516842

RESUMO

The neurotoxin 6-hydroxydopamine (6-OHDA) is frequently used in animal models to mimic Parkinson's disease. Imaging studies describe hyperintense signalling in regions close to the site of the 6-OHDA injection in T2-weighted (T2w) magnetic resonance imaging (MRI). The nature of this hyperintense signal remains elusive and still is matter of discussion. Here we demonstrate hyperintense signalling in T2w MRI and decreased apparent diffusion coefficient (ADC) values following intraventricular injection of 6-OHDA. Moreover, we show decreased GFAP immunoreactivity in brain regions corresponding to the region revealing the hyperintense signalling, probably indicating a loss of astrocytes due to a toxic effect of 6-OHDA. In the striatum, where no hyperintense signalling in MRI was observed following intraventricular 6-OHDA injection, immunohistochemical and molecular analyses revealed an altered expression of the water channel aquaporin 4 and the emergence of vasogenic edema, indicated by an increased perivascular space. Moreover, a significant decrease of claudin-3 immunoreactivity was observed, implying alterations in the blood brain barrier. These findings indicate that intraventricular injection of 6-OHDA results (1) in effects close to the ventricles that can be detected as hyperintense signalling in T2w MRI accompanied by reduced ADC values and (2) in effects on brain regions not adjacent to the ventricles, where a disturbance of water homeostasis occurs. We clearly demonstrate that 6-OHDA leads to brain edema that in turn may affect the overall results of experiments (e.g. behavioral alterations). Therefore, when using 6-OHDA in Parkinson's models effects that are not mediated by degeneration of catecholaminergic neurons have to be considered.


Assuntos
Aquaporina 4/metabolismo , Química Encefálica/efeitos dos fármacos , Encéfalo/patologia , Claudinas/metabolismo , Corpo Estriado/metabolismo , Oxidopamina/farmacologia , Simpatolíticos/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Western Blotting , Catecolaminas/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Claudina-3 , Corpo Estriado/irrigação sanguínea , Corpo Estriado/efeitos dos fármacos , Gliose/induzido quimicamente , Gliose/patologia , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Microinjeções , Atividade Motora/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Percepção Espacial/efeitos dos fármacos
17.
Deep Sea Res 1 Oceanogr Res Pap ; 58(1): 27-37, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21532967

RESUMO

The inner ear structure of Antimora rostrata and its coupling to the swim bladder were analyzed and compared with the inner ears of several shallow-water species that also have similar coupling. The inner ear of Antimora has a long saccular otolith and sensory epithelium as compared to many other fishes. Some parts of the membranous labyrinth are thick and rigid, while other parts are thinner but attached tightly to the bony capsule. The partially rigid membranous labyrinth, along with its intimate connection to the swim bladder, may help the inner ear follow the sound oscillations from the swim bladder with better precision than would occur in a less rigid inner ear. In addition, the saccular sensory epithelium has an elaborate structure and an anterior enlargement that may be correlated with increased hearing sensitivity. Some of the features in the inner ear of Antimora may reflect the functional specialization of deep-water living and support the hypothesis that there is enhanced inner ear sensitivity in some deep-sea fishes.

18.
J Pediatr Hematol Oncol ; 33(1): 50-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21178708

RESUMO

BACKGROUND: Posttransplant lymphoproliferative disease (PTLD) is a serious complication because of the reactivation of the Epstein-Barr virus (EBV). Although after solid organ transplantation (SOT) EBV is typically of recipient origin, after hematopoietic stem cell transplantation (HSCT) donor-derived B cells are usually the source of the EBV-induced lymphoproliferation. OBSERVATION: We report a unique presentation of an EBV-associated PTLD in a 13-year-old boy who underwent 2 subsequent HSCTs from 2 different-sex donors for BCR-ABL-positive acute lymphoblastic leukemia (ALL) and relapses of leukemia, respectively. The PTLD tissue was analyzed for the origin of both B cells and T cells of the lesion. Chimerism analysis done with short tandem repeat systems (STR) showed no autologous signals; approximately 50% of the cells were from the first and second donors, respectively. XY-fluorescence in situ hybridization showed a B-cell PTLD originating from the first donor surrounded by T cells from the second donor. CONCLUSION: This case shows that EBV-infected B cells from a first donor can be the source of a PTLD after a second myeloablative HSCT from a different donor.


Assuntos
Infecções por Vírus Epstein-Barr/etiologia , Proteínas de Fusão bcr-abl/genética , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transtornos Linfoproliferativos/etiologia , Complicações Pós-Operatórias/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Linfócitos B/virologia , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por Vírus Epstein-Barr/virologia , Humanos , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/virologia , Masculino , Complicações Pós-Operatórias/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/virologia , Recidiva , Doadores de Tecidos , Transplante Homólogo
19.
Eur J Radiol ; 69(3): 517-22, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19340958

RESUMO

PURPOSE: To evaluate peri-procedural, early and late complications as well as patients' acceptance of combined ultrasound and fluoroscopy guided radiological port catheter implantation. MATERIALS AND METHODS: In a retrospective analysis, all consecutive radiological port catheter implantations (n = 299) between August 2002 and December 2004 were analyzed. All implantations were performed in an angio suite under analgosedation and antibiotic prophylaxis. Port insertion was guided by ultrasonographic puncture of the jugular (n = 298) or subclavian (n = 1) vein and fluoroscopic guidance of catheter placement. All data of the port implantation had been prospectively entered into a database for interventional radiological procedures. To assess long-term results, patients, relatives or primary physicians were interviewed by telephone; additional data were generated from the hospital information system. Patients and/or the relatives were asked about their satisfaction with the port implantation procedure and long-term results. RESULTS: The technical success rate was 99% (298/299). There were no major complications according to the grading system of SIR. A total of 23 (0.33 per 1000 catheter days) complications (early (n = 4), late (n = 19)) were recorded in the follow-period of a total of 72,727 indwelling catheter days. Infectious complications accounted for 0.15, thrombotic for 0.07 and migration for 0.04 complications per 1000 catheter days. Most complications were successfully treated by interventional measures. Twelve port catheters had to be explanted due to complications, mainly because of infection (n = 9). Patients' and relatives' satisfaction with the port catheter system was very high, even if complications occurred. CONCLUSION: Combined ultrasound and fluoroscopy guided port catheter implantation is a very safe and reliable procedure with low peri-procedural, early and late complication rate. The intervention achieves very high acceptance by the patients and their relatives.


Assuntos
Cateterismo Venoso Central/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Radiografia Intervencionista/estatística & dados numéricos , Ultrassonografia de Intervenção/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Adulto Jovem
20.
Pediatr Blood Cancer ; 53(2): 184-90, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19353621

RESUMO

BACKGROUND: Epstein-Barr virus (EBV) is one of the most frequent triggers of hemophagocytic lymphohistiocytosis (HLH). EBV-associated HLH (EBV-HLH) and ectopic infection of T cells has been particularly described in patients from Far East Asia. PROCEDURE: In a cohort of 12 children with EBV-HLH treated in Germany, the EB viral load was detected by real-time polymerase chain reaction in plasma and peripheral blood mononuclear cells (PBMC). Virological and clinical data were analyzed retrospectively. RESULTS: Among the 12 mainly German patients, children with underlying immunodeficiencies as well as otherwise healthy individuals were affected. The clinical course ranged from a steroid-responding to a fatal disease despite intensive treatment. Increased EBV copy numbers in plasma and/or PBMC were found in all patients. Serial measurements reflected the course of the disease. Cell-type specific viral load was determined in seven patients and revealed EBV-infection of T cells in all of them. In contrast to the reported Asian patients a significant viral load was also found in B cells. CONCLUSIONS: T cell infection appears to be a typical feature of EBV-associated HLH irrespective of patients ethnic background and the clinical course. Evaluation of cell-type specific infection should be considered when targeted therapy is applied.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Linfo-Histiocitose Hemofagocítica/virologia , Linfócitos T/virologia , Adolescente , Criança , Pré-Escolar , DNA Viral/isolamento & purificação , Infecções por Vírus Epstein-Barr/etnologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Alemanha , Herpesvirus Humano 4/isolamento & purificação , Humanos , Linfo-Histiocitose Hemofagocítica/etnologia , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Viral
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