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1.
J Oral Rehabil ; 51(6): 1025-1033, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38475974

RESUMO

BACKGROUND: Longitudinal intervention studies on treatment options in temporomandibular dysfunction (TMD) including self reports and salivary biomarkers of stress are rare and the exact therapeutic function of occlusal splints widely unknown. METHODS: We examined the therapeutic effects of a Michigan splint with occlusal relevance in patients with TMD using a placebo-controlled, delayed-start design. Two intervention groups received a Michigan splint, while one of them had a placebo palatine splint for the first 3 weeks. We collected pain intensities (at rest and after five occlusal movements), salivary measures associated with stress (cortisol and alpha-amylase) and self-reported psychological distress (stress, anxiety, catastrophizing) at baseline and 3 and 7 weeks after onset of intervention. RESULTS: At baseline, we observed increased pain intensity and psychological distress in TMD patients compared to 11 matched healthy controls. Baseline anxiety was linked to movement pain intensity through stress. Over therapy reductions in pain intensity and morning cortisol were more pronounced in those patients starting immediately with the Michigan splint, while psychological distress decreased similarly in both groups. CONCLUSION: Our results suggest that perceived stress plays a role for the association between anxiety and TMD pain and underlines the need for an interdisciplinary perspective on the pathogenesis and therapy of TMD in a setting where psychotherapeutic knowledge is still scarce or rarely applied.


Assuntos
Biomarcadores , Hidrocortisona , Placas Oclusais , Medição da Dor , Saliva , Estresse Psicológico , Transtornos da Articulação Temporomandibular , Humanos , Feminino , Transtornos da Articulação Temporomandibular/psicologia , Transtornos da Articulação Temporomandibular/terapia , Transtornos da Articulação Temporomandibular/fisiopatologia , Transtornos da Articulação Temporomandibular/metabolismo , Transtornos da Articulação Temporomandibular/complicações , Adulto , Masculino , Saliva/química , Saliva/metabolismo , Biomarcadores/análise , Biomarcadores/metabolismo , Estresse Psicológico/terapia , Estresse Psicológico/metabolismo , Hidrocortisona/metabolismo , Hidrocortisona/análise , Resultado do Tratamento , Dor Facial/terapia , Dor Facial/psicologia , Dor Facial/fisiopatologia , Dor Facial/metabolismo , Pessoa de Meia-Idade , Adulto Jovem , alfa-Amilases/metabolismo , alfa-Amilases/análise
2.
Arch Orthop Trauma Surg ; 141(7): 1131-1137, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32524227

RESUMO

BACKGROUND: With the novel coronavirus-induced disease (COVID-19), there is the fear of nosocomial infections and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmissions to healthcare workers (HCW). We report the case of a 64-year-old male patient who underwent explantation of a shoulder prosthesis due to a periprosthetic infection. He was tested SARS-CoV-2 positive 7 days after admission to the orthopaedic department following strict infection control measures, routinely including screening all patients for multi-drug-resistant organism (MDRO) colonization upon admission. Aim of our study is to report on the spreading potential of SARS-CoV-2 in a healthcare setting if standard contact precautions and infection control measures have been established. METHODS: All HCW with exposure to the patient from day of admission until confirmed diagnosis of COVID-19 were identified and underwent oropharyngeal swab testing for SARS-CoV-2 by real-time RT-PCR. RESULTS: Sixty-six HCW were identified: nine orthopaedic surgeons, four anaesthesiologists, 25 orthopaedic nurses, five nurse anesthetists, eight scrub nurses, five nursing students, two medical assistants and seven service employees. Fourteen HCW (21%) showed clinical symptoms compatible with a SARS-CoV-2 infection: cough (n = 4), sore throat (n = 3), nasal congestion (n = 3), dyspnea (n = 2), fever (n = 1), headache and myalgia (n = 1). SARS-CoV-2 was not detected in any of the 66 HCW. CONCLUSION: Hygienic measures and contact precautions, aimed at preventing the spread of MRDO, may have helped to prevent a SARS-CoV-2 transmission to HCW-despite high-risk exposure during intubation, surgical treatment and general care. LEVEL OF EVIDENCE: IV, case series.


Assuntos
COVID-19 , Pessoal de Saúde , Controle de Infecções , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Exposição Ocupacional , COVID-19/diagnóstico , COVID-19/prevenção & controle , COVID-19/transmissão , Teste de Ácido Nucleico para COVID-19/métodos , Busca de Comunicante/métodos , Remoção de Dispositivo/métodos , Pessoal de Saúde/classificação , Pessoal de Saúde/estatística & dados numéricos , Humanos , Controle de Infecções/métodos , Controle de Infecções/organização & administração , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Procedimentos Ortopédicos/métodos , Infecções Relacionadas à Prótese/cirurgia , Gestão de Riscos , SARS-CoV-2 , Ombro/cirurgia
3.
Musculoskelet Surg ; 105(2): 149-153, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31691179

RESUMO

PURPOSE: This study compares the clinical results of the Whipple, empty-can, and full-can tests to detect supraspinatus tendon tears. We determined the sensitivities, specificities, and positive and negative predictive values of each test with respect to the intraoperative supraspinatus tendon lesion confirmation. METHODS: We examined 61 patients (26 women, 35 men) presenting for arthroscopic surgery with functional disability or persisting shoulder pain. All the patients underwent Whipple, empty-can, and full-can testing. We correlated the clinical results of the tests with the confirmation of a supraspinatus tendon lesion by direct arthroscopic visualization. RESULTS: We examined 34 right and 27 left shoulders. For full and partial supraspinatus tendon tears, the Whipple test showed a sensitivity of 88.6% and a specificity of 29.4%, whereas the empty-can test and the full-can test had sensitivities of 88.6% and 75.0%, and specificities of 58.8% and 47.1%, respectively. CONCLUSIONS: Compared with the empty-can test and the full-can test, the Whipple test was less specific, while its sensitivity was equal to that of the empty-can test and higher than that for the full-can test. Because of its low specificity, the Whipple test has a high risk of false-positive results in comparison with the other tests.


Assuntos
Lesões do Manguito Rotador , Traumatismos dos Tendões , Artroscopia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Manguito Rotador , Lesões do Manguito Rotador/diagnóstico por imagem , Lesões do Manguito Rotador/cirurgia , Traumatismos dos Tendões/diagnóstico , Traumatismos dos Tendões/cirurgia , Tendões
4.
Phys Chem Chem Phys ; 16(30): 15910-6, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24964099

RESUMO

On the basis of experiments at 275 GHz, we reconsider the dependence of the continuous-wave EPR spectra of nitroxide spin-labeled protein sites in sensory- and bacteriorhodopsin on the micro-environment. The high magnetic field provides the resolution necessary to disentangle the effects of hydrogen bonding and polarity. In the gxx region of the 275 GHz EPR spectrum, bands are resolved that derive from spin-label populations carrying no, one or two hydrogen bonds. The gxx value of each population varies hardly from site to site, significantly less than deduced previously from studies at lower microwave frequencies. The fractions of the populations vary strongly, which provides a consistent description of the variation of the average gxx and the average nitrogen-hyperfine interaction Azz from site to site. These variations reflect the difference in the proticity of the micro-environment, and differences in polarity contribute marginally. Concomitant W-band ELDOR-detected NMR experiments on the corresponding nitroxide in perdeuterated water resolve population-specific nitrogen-hyperfine bands, which underlies the interpretation for the proteins.


Assuntos
Ligação de Hidrogênio , Proteínas de Membrana/química , Óxidos de Nitrogênio/química , Marcadores de Spin , Espectroscopia de Ressonância de Spin Eletrônica
5.
Cell Death Differ ; 21(2): 234-46, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24037089

RESUMO

We previously reported that STAT1 expression is frequently abrogated in human estrogen receptor-α-positive (ERα(+)) breast cancers and mice lacking STAT1 spontaneously develop ERα(+) mammary tumors. However, the precise mechanism by which STAT1 suppresses mammary gland tumorigenesis has not been fully elucidated. Here we show that STAT1-deficient mammary epithelial cells (MECs) display persistent prolactin receptor (PrlR) signaling, resulting in activation of JAK2, STAT3 and STAT5A/5B, expansion of CD61(+) luminal progenitor cells and development of ERα(+) mammary tumors. A failure to upregulate SOCS1, a STAT1-induced inhibitor of JAK2, leads to unopposed oncogenic PrlR signaling in STAT1(-/-) MECs. Prophylactic use of a pharmacological JAK2 inhibitor restrains the proportion of luminal progenitors and prevents disease induction. Systemic inhibition of activated JAK2 induces tumor cell death and produces therapeutic regression of pre-existing endocrine-sensitive and refractory mammary tumors. Thus, STAT1 suppresses tumor formation in mammary glands by preventing the natural developmental function of a growth factor signaling pathway from becoming pro-oncogenic. In addition, targeted inhibition of JAK2 may have significant therapeutic potential in controlling ERα(+) breast cancer in humans.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Janus Quinase 2/metabolismo , Neoplasias Mamárias Animais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT1/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Compostos Heterocíclicos com 3 Anéis/farmacologia , Janus Quinase 2/antagonistas & inibidores , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/genética , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Fator de Transcrição STAT1/deficiência , Transdução de Sinais/efeitos dos fármacos , Proteína 1 Supressora da Sinalização de Citocina
6.
Biomacromolecules ; 14(8): 2582-92, 2013 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-23819749

RESUMO

The structure and conformational dynamics of insulin entrapped into a silica matrix was monitored during the sol to maturated-gel transition by electron paramagnetic resonance (EPR) spectroscopy. Insulin was successfully spin-labeled with iodoacetamide and the bifunctional nitroxide reagent HO-1944. Room temperature continuous wave (cw) EPR spectra of insulin were recorded to assess the mobility of the attached spin labels. Insulin conformation and its distribution within the silica matrix were studied using double electron-electron resonance (DEER) and low-temperature cw-EPR. A porous oxide matrix seems to form around insulin molecules with pore diameters in the order of a few nanometers. Secondary structure of the encapsulated insulin investigated by Fourier transform infrared spectroscopy proved a high structural integrity of insulin even in the dried silica matrix. The results show that silica encapsulation can be used as a powerful tool to effectively isolate and functionally preserve biomolecules during preparation, storage, and release.


Assuntos
Portadores de Fármacos/química , Hipoglicemiantes/química , Insulina/química , Sílica Gel/química , Animais , Bovinos , Composição de Medicamentos , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Modelos Moleculares , Nanopartículas/química , Tamanho da Partícula , Transição de Fase , Porosidade , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier , Marcadores de Spin
8.
J Neurooncol ; 83(1): 17-29, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17206475

RESUMO

Certain risk groups among tumors of the central nervous system (CNS) in children take an almost inevitably fatal course. The elucidation of molecular mechanisms offers hope for improved therapy. Aberrant methylation is common in malignant brain tumors of childhood and may have implications for stratification and therapy. Methylation of p16 (INK4A), p14 (ARF), TIMP3, CDH1, p15 (INK4B )and DAPK1 in medulloblastoma (MB) and ependymoma has been discussed controversially in the literature. DUTT1 and SOCS1 have not previously been analyzed. We examined methylation in MB, sPNET and ependymoma using methylation-specific PCR (MSP), quantitative Combined Bisulfite Restriction Analysis (COBRA) and direct and clone sequencing of bisulfite PCR products. We detected methylation of p16 (INK4A) (17/43), p14 (ARF) (11/42) and TIMP3 (9/44) in MB and others by MSP. CDH1 was not only methylated in MB (31/41), but also in normal controls. Evaluation of MSP results by quantitative COBRA and sequencing yielded methylation between the detection limits of COBRA (1%) and MSP (0.1%). Only p16 (INK4A )and TIMP3 were methylated consistently in medulloblastomas (p16 (INK4A ) 14%, TIMP3 11%) and p16 (INK4A) also in anaplastic ependymomas (1/4 tumors). Methylation ranged from 1-5%. Evaluation of methylation using MSP has thus to be supplemented by quantitative methods. Our analyses raise the issue of the functional significance of low level methylation, which may disturb the delicate growth factor equilibrium within the cell. Therapeutic and diagnostic implications urge into depth analyses of methylation as a mechanism, which might fill some of the gaps of our understanding of brain tumor origin.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Cerebelares/genética , Metilação de DNA , Genes p16 , Meduloblastoma/genética , Tumores Neuroectodérmicos Primitivos/genética , Inibidor Tecidual de Metaloproteinase-3/genética , Adolescente , Adulto , Idoso , Proteínas Reguladoras de Apoptose/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Criança , Pré-Escolar , Proteínas Quinases Associadas com Morte Celular , Feminino , Inativação Gênica , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Receptores Imunológicos/genética , Proteínas Roundabout
9.
Histopathology ; 50(2): 252-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17222254

RESUMO

AIMS: To report the demographic, clinical and molecular profile of a series of intraspinal nerve sheath myxomas. Nerve sheath myxomas are diagnostically challenging, mainly cutaneous spindle cell neoplasms exhibiting Schwann cell differentiation. They are frequently mistaken for neurothekeomas and their genetic features are essentially unknown. METHODS AND RESULTS: Ten spinal nerve sheath myxomas with a preferential location in the lumbar spine (70%) were investigated. Presenting symptoms consisted of sciatic pain (100%), muscle weakness and paraesthesia (60% each). Intraoperatively, all tumours were attached to a spinal nerve. Chromosomal imbalances by comparative genomic hybridization were found in 8/10 cases, consisting of -22q (80%) and -19 (30%). Polymerase chain reaction analysis of the NF2 gene (exons 1-16) revealed two tumours with mutations in exon 8 and 14, respectively. CONCLUSIONS: Although these 10 nerve sheath myxomas exhibited Schwann cell differentiation and frequently showed loss of chromosome 22q typically encountered in peripheral nerve tumours, only two cases demonstrated mutations of the NF2 gene. This may indicate involvement of other tumour suppressor genes on 22q in nerve sheath myxomas and shows that they are more closely related at the molecular level to sporadic schwannomas, underscoring the presumption that they are true nerve sheath tumours.


Assuntos
Aberrações Cromossômicas , Neurofibromina 2/genética , Neurotecoma/genética , Nervos Espinhais/patologia , Adulto , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurotecoma/patologia
10.
J Neural Transm (Vienna) ; 113(6): 721-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16604299

RESUMO

Neuromelanin is a dark-coloured pigment which forms in the dopamine neurons of the human midbrain. Here we describe the age-related development and regulation of neuromelanin within these dopamine neurons. 10 microm sections from formalin-fixed midbrain from 29 people spanning the ages of 24 weeks to 95 years old were either stained with a basic Nissl substance stain (0.5% cresyl violet), or processed unstained. After locating the substantia nigra using the stained sections, digital photos were taken of individual ventral substantia nigra neurons in the unstained sections, and the cellular area occupied by pigment, and optical density were measured using computer software. These measurements demonstrated three developmental phases. Neuromelanin was not present at birth and initiation of pigmentation began at approximately 3 years of age, followed by a period of increasing pigment granule number and increasing pigment granule colouration until age 20. In middle and later life the colour of the pigment granules continued to darken but was not associated with any substantial growth in pigment volume. The identification of three phases and changes in the rate of neuromelanin production over time suggests the regulation of neuromelanin production and turnover, possibly through enzymatic processes.


Assuntos
Dopamina/metabolismo , Melaninas/metabolismo , Neurônios/fisiologia , Pigmentos Biológicos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Humanos , Pessoa de Meia-Idade , Neurônios/citologia , Neurônios/metabolismo , Substância Negra/química , Substância Negra/citologia
11.
Neuropathol Appl Neurobiol ; 32(3): 278-83, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16640646

RESUMO

The histopathology of papillary tumours of the pineal region (PTPR) closely resembles that of ependymomas and choroid plexus tumours. Therefore, immunohistochemical staining profiles were investigated in a series of 15 PTPR. In addition to cytokeratin, synaptophysin and glial fibrillary acidic protein expression, PTPR were examined for the presence of dot- or ring-like epithelial membrane antigen (EMA) immunoreactivity typically encountered in ependymoma, staining for inwardly rectifying potassium channel Kir7.1 and stanniocalcin-1 (specifically expressed in choroid plexus tumours) as well as microtubule-associated protein-2 (MAP-2). Furthermore, comparative genomic hybridization was performed in five PTPR. Cytokeratin was expressed in all PTPR examined, whereas glial fibrillary acidic protein and synaptophysin staining were absent. Dot- or ring-like EMA immunoreactivity was only observed in 1 out of 15 PTPR. Membranous Kir7.1 and cytoplasmic stanniocalcin-1 staining were present in the minority of PTPR (3/15 and 4/15, respectively). In contrast, MAP-2 immunoreactivity was encountered in 13 out of 15 PTPR, but was significantly less frequently observed in a series of choroid plexus tumours (7/37). PTPR mainly presented with chromosomal losses affecting chromosomes 10 (4/5 cases) and 22q (3/5 cases) as well as gains on chromosomes 4 (4/5 cases), 8 (3/5 cases), 9 (3/5 cases) and 12 (3/5 cases). To conclude, the majority of PTPR can be distinguished from ependymomas and choroid plexus tumours by absent staining for epithelial membrane antigen, Kir7.1 and staniocalcin-1 as well as the presence of distinct MAP-2 immunoreactivity. Antibodies directed against these antigens are thus expected to be valuable markers in the diagnosis of papillary tumours located in the vicinity of the third ventricle.


Assuntos
Adenocarcinoma Papilar/genética , Adenocarcinoma Papilar/metabolismo , Biomarcadores Tumorais/análise , Pinealoma/genética , Pinealoma/metabolismo , Adenocarcinoma Papilar/patologia , Adolescente , Adulto , Idoso , Criança , Neoplasias do Plexo Corióideo/patologia , Aberrações Cromossômicas , Diagnóstico Diferencial , Ependimoma/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , Pinealoma/patologia
12.
Neurobiol Aging ; 27(3): 506-12, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15916835

RESUMO

Neuromelanin is a dark-coloured pigment which forms in the dopamine neurons of the human midbrain. The age-related development and regulation of neuromelanin within these dopamine neurons has not been previously described. Optical density and area measurements of unstained neuromelanin in ventral substantia nigra neurons from 29 people spanning the ages of 24 weeks to 95 years old, demonstrated three developmental phases. Neuromelanin was not present at birth and initiation of pigmentation began at approximately 3 years of age, followed by a period of increasing pigment granule number and increasing pigment granule colouration until age 20. In middle and later life the colour of the pigment granules continued to darken but was not associated with any substantial growth in pigment volume. The identification of three phases and changes in the rate of neuromelanin production over time suggests the regulation of neuromelanin production and turnover, possibly through enzymatic processes.


Assuntos
Envelhecimento/metabolismo , Melaninas/metabolismo , Neurônios/metabolismo , Substância Negra/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cadáver , Criança , Pré-Escolar , Medicina Baseada em Evidências , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Distribuição Tecidual
13.
Oncogene ; 25(7): 1111-7, 2006 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-16186793

RESUMO

Supratentorial primitive neuroectodermal tumors (sPNET) and atypical teratoid/rhabdoid tumors (AT/RT) of the CNS represent a biological and clinical enigma, despite advances in both molecular techniques and clinical management for these two rare embryonal brain tumors of childhood. Epigenetic changes hold great potential as possible disease mechanisms and may be manipulated therapeutically. We thus studied aberrant methylation of the genes RASSF1A and CASP8 and its consequence on expression in cell lines and primary tumors using a combination of semiquantitative methylation specific PCR (MSP), bisulfite sequencing and RT-PCR. In all, 17 samples of autopsy-derived normal appearing brain served as controls. Opposed to control tissues 19/24 sPNET and 4/6 AT/RT demonstrated aberrant methylation for the RASSF1A promoter region. Treatment of cell lines using 5-Aza-2'-deoxycytidine (5AZA) alone or in combination with trichostatin A (TSA) succeeded in re-establishing expression of RASSF1A in cell lines derived from a renal rhabdoid, an AT/RT and a medulloblastoma. A 5' CpG-rich region of CASP8 was methylated in normal tissues and in tumors. However, CASP8 showed inconsistent expression patterns in normal and tumor tissues. Our results indicate that aberrant methylation of the RASSF1A promoter region may be of importance in the origin and progression of sPNET and AT/RT while the analysed 5'-CpG rich region of the CASP8 gene does not seem to play an important role in these tumors. Further studies of epigenetic changes in these rare tumors are warranted as their biology remains obscure and treatment efforts have been rather unsuccessfull.


Assuntos
Neoplasias Encefálicas/genética , Metilação de DNA , Inativação Gênica , Tumores Neuroectodérmicos Primitivos/genética , Tumor Rabdoide/genética , Teratoma/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Caspase 8 , Caspases/genética , Criança , Pré-Escolar , Ilhas de CpG , Metilação de DNA/efeitos dos fármacos , Decitabina , Epigênese Genética , Feminino , Inativação Gênica/efeitos dos fármacos , Humanos , Ácidos Hidroxâmicos/farmacologia , Lactente , Masculino , Regiões Promotoras Genéticas
14.
Nuklearmedizin ; 44(4): 131-6, 2005.
Artigo em Alemão | MEDLINE | ID: mdl-16163408

RESUMO

PURPOSE: To evaluate single photon emission computed tomography (SPECT) using the amino acid l-3-[123I]-alpha-methyl tyrosine (IMT) and contrast enhanced magnetic resonance imaging (MRI) as diagnostic tools in primary paediatric brain tumours in respect of non-invasive tumour grading. Patients, materials, methods: 45 children with primary brain tumours were retrospectively evaluated. IMT uptake was quantified as tumour/nontumour-ratio, a 4-value-scale was used to measure gadolinium enhancement on contrast enhanced MRI. Statistical analyses were performed to evaluate IMT uptake and gadolinium enhancement in low (WHO I/II) and high (WHO III/IV) grade tumours and to disclose a potential relationship of IMT uptake to disruption of blood brain barrier as measured in corresponding MRI scans. RESULTS: IMT uptake above background level was observed in 35 of 45 patients. IMT uptake was slightly higher in high grade tumours but the difference failed to attain statistical significance. Grading of individual tumours was neither possible by IMT SPECT nor by gadolinium enhanced MRI. CONCLUSION: IMT is accumulated in most brain tumours in children. Tumour grading was not possible using IMT or contrast enhancement as determined by MRI. Neither morphological nor functional imaging can replace histology in paediatric brain tumours.


Assuntos
Aminoácidos , Neoplasias Encefálicas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons , Adolescente , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Tomografia Computadorizada de Emissão de Fóton Único
15.
Eur J Nucl Med Mol Imaging ; 32(4): 422-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15650870

RESUMO

PURPOSE: The aim of this study was to evaluate the differential uptake of O-(2-[18F]fluorethyl)-L-tyrosine (FET) in suspected primary brain tumours. METHODS: Positron emission tomography (PET) was performed in 44 patients referred for the evaluation of a suspected brain tumour. Acquisition consisted of four 10-min frames starting upon i.v. injection of FET. Tumour uptake was calculated as the ratio of maximal tumour intensity to mean activity within a reference region (FETmax). RESULTS: FET uptake above the cortical level was observed in 35/44 lesions. All histologically confirmed gliomas and many other lesions showed FET uptake to a variable extent. No uptake was observed in nine lesions (one inflammatory lesion, one dysembryoplastic neuroepithelial tumour, one mature teratoma, six lesions without histological confirmation). An analysis of uptake dynamics was done in the patients with increased FET uptake (22 gliomas, three lymphomas, three non-neoplastic lesions, three lesions with unknown histology and four other primaries). Upon classification of tumours into low (i.e. WHO I and II) and high grade (i.e. WHO III and IV), a significant difference in FETmax between the two categories was observed only in the first image frame (0-10 min p.i.), with FETmax=2.0 in low-grade and 3.2 in high-grade tumours (p<0.05); no significant differences were found in frame 4 (30-40 min p.i.), with FETmax=2.4 vs 2.7. Similar results were obtained when the analysis was applied only to astrocytic tumours (2.0 vs 3.1 in the first frame; 2.4 vs 2.6 in the fourth frame). CONCLUSION: These initial results indicate that FET PET is a useful method to identify malignant brain lesions. It appears that high- and low-grade brain tumours exhibit a different uptake kinetics of FET. A kinetic analysis of FET PET may provide additional information in the differentiation of suspected brain lesions.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/metabolismo , Radioisótopos de Flúor/farmacocinética , Tomografia por Emissão de Pósitrons/métodos , Tirosina/análogos & derivados , Tirosina/farmacocinética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Nervenarzt ; 75(8): 763-9, 2004 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-15118826

RESUMO

BACKGROUND: During the course of HIV infection, the majority of patients develop opportunistic cerebral neuro-manifestations. If conventional diagnostic tools are not sufficient, a stereotactic biopsy is often necessary. PATIENTS AND METHODS: In order to evaluate the correctness of the clinical diagnosis of cerebral neuro-manifestations in HIV-infected patients, we compared the results of cerebral biopsy or autopsy with the previous clinical diagnosis. A total of 19 biopsies and 49 autopsies could be analyzed. RESULTS: Except for HIV-associated encephalopathy, we detected a very high conformity between the clinical and the neuropathological diagnoses. We obtained the best sensitivity for progressive multifocal leukoencephalopathy (PML), whereas for cerebral toxoplasmosis the worst sensitivity and specificity was identified. CONCLUSION: We conclude that the diagnosis of PML can be made on clinical grounds alone, whereas the diagnosis of cerebral toxoplasmosis and lymphoma often requires a biopsy, which should be performed early.


Assuntos
Complexo AIDS Demência/patologia , Síndrome da Imunodeficiência Adquirida/patologia , Encefalopatias/patologia , Encéfalo/patologia , Leucoencefalopatia Multifocal Progressiva/patologia , Toxoplasmose Cerebral/patologia , Adulto , Biópsia , Encefalopatias/diagnóstico , Neoplasias Encefálicas/patologia , Cadáver , Diagnóstico Diferencial , Feminino , Humanos , Técnicas In Vitro , Linfoma/patologia , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Estatística como Assunto , Técnicas Estereotáxicas
18.
Acta Neurochir (Wien) ; 145(12): 1127-31, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14663572

RESUMO

BACKGROUND: Symptomatic plasma cell granulomas (PCG) of the central nervous system (CNS) are a rare entity, especially in association with an extracranial manifestation. CLINICAL PRESENTATION: A 13 years old boy was operated on for a symptomatic plasma cell granuloma of the lower lobe of the left lung. Four years later, he suffered his first generalized seizure. CT and MRI scans revealed a small hyperdense lesion, which was located in the right frontal lobe, adjacent to the motor strip. Intervention. Stereotactic guided surgery was performed. A plasma cell granuloma was found, which histopathologically resembled the intrapulmonary lesion, which had been removed four years ago. CONCLUSION: Histological findings, differential diagnosis and specific treatment are reviewed and discussed. Patients with PCG should be radiologically staged. Long term prognosis of PCG is good in cases surgically resectable. Nevertheless, patients require lifelong follow up.


Assuntos
Encefalopatias/cirurgia , Lobo Frontal/cirurgia , Granuloma de Células Plasmáticas/cirurgia , Granuloma de Células Plasmáticas Pulmonar/cirurgia , Complicações Pós-Operatórias/cirurgia , Adolescente , Encefalopatias/diagnóstico , Encefalopatias/patologia , Diagnóstico Diferencial , Epilepsia Generalizada/etiologia , Seguimentos , Lobo Frontal/patologia , Granuloma de Células Plasmáticas/diagnóstico , Granuloma de Células Plasmáticas/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Microcirurgia , Granuloma de Células Plasmáticas Pulmonar/diagnóstico , Granuloma de Células Plasmáticas Pulmonar/patologia , Complicações Pós-Operatórias/diagnóstico , Reoperação , Tomografia Computadorizada por Raios X
19.
J Neurol Neurosurg Psychiatry ; 74(2): 260-1, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12531965

RESUMO

Craniopharyngiomas are among the most common paediatric tumours and are thought to arise from embryonic remnants of Rathke's pouch. The molecular mechanisms involved in their formation remain elusive and little is known about chromosomal imbalances that could suggest the locations of tumour suppressor or proto-oncogenes involved in the pathogenesis. The paucity of published data on the molecular basis of such tumours prompted this investigation of 20 adamantinomatous and nine papillary craniopharyngiomas for genetic abnormalities by comparative genomic hybridisation (CGH). CGH revealed no DNA copy number changes in any of the 29 primary craniopharyngiomas, regardless of their histological subtype. These data suggest that chromosomal imbalances are a rare event in both adamantinomatous and papillary craniopharyngiomas.


Assuntos
Aberrações Cromossômicas , Craniofaringioma/genética , Neoplasias Hipofisárias/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Craniofaringioma/patologia , DNA de Neoplasias/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , Hipófise/patologia , Neoplasias Hipofisárias/patologia
20.
Int J Legal Med ; 116(4): 233-7, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12420703

RESUMO

We present the case of a 10-year-old girl with cardiomyopathy who received a heart transplant. Due to organ rejection, the dosage of immunosuppressive agents was increased postoperatively. The patient complained of intermittent headaches in the following days and developed a haemorrhagic necrosis of the left thalamus. A week later, an oral dose of cyclosporin A was accidentally given intravenously, and 2 weeks later a recurrent subarachnoid haemorrhage of unknown origin was diagnosed. The clinical course was then characterised by progressive deterioration resulting in coma, fluctuating brain stem symptoms and the development of a massive cerebral oedema with subsequent brain death. A coroner's autopsy was instigated to investigate a claim of medical misadventure. Neuropathological investigations found a focal infiltration of fungal hyphae in the left posterior cerebral artery resulting in necrosis of the vascular wall and thus explaining the source of the recurrent subarachnoid haemorrhage which eventually resulted in the girl's death. Medical misadventure due to the administration of cyclosporin was not directly responsible for the death of this patient. This case illustrates that it is of paramount importance to copiously sample and investigate the basal cerebral arteries in cases of subarachnoid haemorrhage of unknown origin, in particular in a medico-legal context.


Assuntos
Aspergilose/diagnóstico , Transplante de Coração , Erros de Medicação , Vasculite do Sistema Nervoso Central/diagnóstico , Aspergilose/complicações , Autopsia , Criança , Evolução Fatal , Feminino , Alemanha , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Hemorragia Subaracnoídea Traumática/etiologia , Vasculite do Sistema Nervoso Central/complicações
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