Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 323
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
2.
J Dairy Sci ; 101(2): 1777-1784, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29224857

RESUMO

European starlings are an invasive bird species in North America that are known to cause damage to commercial dairies through the consumption of total mixed rations (TMR) destined for dairy cows. We hypothesized that large foraging flocks of starlings alter the physical composition of TMR, and that this change may be significant enough to affect milk production. To better determine if production losses could potentially occur in commercial dairies as a consequence of feed consumption by foraging flocks of starlings, we conducted controlled feeding experiments using a TMR sourced from a commercial dairy that is chronically plagued with seasonal starling damage. European starlings selected the high-energy fraction of the TMR and reduced starch and crude fat availability. Using the dairy National Research Council production model equations, the nutritional changes measured in the controlled feeding experiments could potentially reduce the productivity of dairies. Model output suggests that for Holsteins producing 32 kg of milk/d, total required net energy intake (NEI) was 31.5 Mcal/d. Within the reference TMR, NEI supplied was 29.3 Mcal/d, whereas within the starling-consumed TMR NEI supplied was 27.7 Mcal/d. Following our nutrition experiments, we assessed the efficacy of pelleted feed as a deterrent strategy for bird damage management in commercial dairies. Six different pelleted feed treatments of differing diameter were offered to starlings. All pellets of 0.95 cm diameter or larger inhibited starling consumption by ≥79%.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Leite/metabolismo , Estorninhos/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ingestão de Energia , Comportamento Alimentar , Feminino , Lactação , América do Norte
3.
Clin Exp Immunol ; 188(1): 63-78, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27880975

RESUMO

Systemic lupus erythematosus (SLE) is a common autoimmune disorder with a complex and poorly understood immunopathogenesis. However, a pathogenic role for the T helper type 17 (Th17) axis was demonstrated by many studies, while regulatory T cells (Tregs ) were shown to mediate protection. Recently, we and others characterized a novel and independent T cell population expressing both the Treg characteristic transcription factor forkhead box protein 3 (FoxP3) and the Th17-defining retinoic acid receptor-related orphan nuclear receptor γt (RORγt). Studies in a model of acute glomerulonephritis unveiled potent regulatory, but also proinflammatory, functions of RORγt+ FoxP3+ Tregs . This bi-functional nature prompted us to suggest the name 'biTregs '. Importantly, the pathogenic biTreg effects were dependent upon expression of RORγt. We thus aimed to evaluate the contribution of RORγt+ FoxP3+ biTregs to pristane-induced SLE and explored the therapeutic potential of interference with RORγt activation. Our analyses revealed expansion of IL-17 producing biTregs in a distinctive time-course and organ-specific pattern, coincident with the development of autoimmunity and tissue injury. Importantly, specific ablation of RORγt activation in endogenous biTregs resulted in significant amelioration of pristane-induced pulmonary vasculitis and lupus nephritis. As potential mechanisms underlying the observed protection, we found that secretion of IL-17 by biTregs was abrogated completely in FoxP3Cre  × RORCfl/fl mice. Furthermore, Tregs showed a more activated phenotype after cell-specific inactivation of RORγt signalling. Finally, and remarkably, biTregs were found to potently suppress anti-inflammatory Th2 immunity in a RORγt-dependent manner. Our study thus identifies biTregs as novel players in SLE and advocates RORγt-directed interventions as promising therapeutic strategies.


Assuntos
Expressão Gênica , Interleucina-17/metabolismo , Lúpus Eritematoso Sistêmico/etiologia , Lúpus Eritematoso Sistêmico/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Animais , Citocinas/sangue , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Imunidade Humoral , Imunomodulação , Imunofenotipagem , Pulmão/metabolismo , Pulmão/patologia , Lúpus Eritematoso Sistêmico/patologia , Nefrite Lúpica/etiologia , Nefrite Lúpica/metabolismo , Nefrite Lúpica/patologia , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fenótipo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Células Th2/imunologia , Células Th2/metabolismo
4.
Eur Radiol ; 27(8): 3443-3451, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27988890

RESUMO

OBJECTIVES: To evaluate the diagnostic accuracy of multidetector CT (MDCT) for detection of lumbar disc herniation with MRI as standard of reference. METHODS: Patients with low back pain underwent indicated MDCT (128-row MDCT, helical pitch), 60 patients with iterative reconstruction (IR) and 67 patients with filtered back projection (FBP). Lumbar spine MRI (1.5 T) was performed within 1 month. Signal-to-noise ratios (SNR) of cerebrospinal fluid (CSF), annulus fibrosus (AF) and the spinal cord (SC) were determined for all modalities. Two readers independently rated image quality (IQ), diagnostic confidence and accuracy in the diagnosis of lumbar disc herniation using MRI as standard of reference. Inter-reader correlation was assessed with weighted κ. RESULTS: Sensitivity, specificity, precision and accuracy of MDCT for disc protrusion were 98.8%, 96.5%, 97.1%, 97.8% (disc level), 97.7%, 92.9%, 98.6%, 96.9% (patient level). SNR of IR was significantly higher than FBP. IQ was significantly better in IR owing to visually reduced noise and improved delineation of the discs. κ (>0.90) was excellent for both algorithms. CONCLUSION: MDCT of the lumbar spine yields high diagnostic accuracy for detection of lumbar disc herniation. IR improves image quality so that the provided diagnostic accuracy is principally equivalent to MRI. KEY POINTS: • MDCT is an accurate alternative to MRI in disc herniation diagnosis. • By IR enhanced image quality improves MDCT diagnostic confidence similar to MRI. • Advances in CT technology contribute to improved diagnostic performance in lumbar spine imaging.


Assuntos
Deslocamento do Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Deslocamento do Disco Intervertebral/complicações , Dor Lombar/diagnóstico por imagem , Dor Lombar/etiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/métodos , Radiculopatia/diagnóstico por imagem , Radiculopatia/etiologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Razão Sinal-Ruído
5.
Radiologe ; 56(8): 708-16, 2016 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-27338267

RESUMO

BACKGROUND: In hospitals, the radiological services provided to non-privately insured in-house patients are mostly distributed to requesting disciplines through internal cost allocation (ICA). In many institutions, computed tomography (CT) is the modality with the largest amount of allocation credits. OBJECTIVES: The aim of this work is to compare the ICA to respective DRG (Diagnosis Related Groups) shares for diagnostic CT services in a university hospital setting. MATERIALS AND METHODS: The data from four CT scanners in a large university hospital were processed for the 2012 fiscal year. For each of the 50 DRG groups with the most case-mix points, all diagnostic CT services were documented including their respective amount of GOÄ allocation credits and invoiced ICA value. As the German Institute for Reimbursement of Hospitals (InEK) database groups the radiation disciplines (radiology, nuclear medicine and radiation therapy) together and also lacks any modality differentiation, the determination of the diagnostic CT component was based on the existing institutional distribution of ICA allocations. RESULTS: Within the included 24,854 cases, 63,062,060 GOÄ-based performance credits were counted. The ICA relieved these diagnostic CT services by € 819,029 (single credit value of 1.30 Eurocent), whereas accounting by using DRG shares would have resulted in € 1,127,591 (single credit value of 1.79 Eurocent). The GOÄ single credit value is 5.62 Eurocent. CONCLUSIONS: The diagnostic CT service was basically rendered as relatively inexpensive. In addition to a better financial result, changing the current ICA to DRG shares might also mean a chance for real revenues. However, the attractiveness considerably depends on how the DRG shares are distributed to the different radiation disciplines of one institution.


Assuntos
Centros Médicos Acadêmicos/economia , Alocação de Custos/economia , Grupos Diagnósticos Relacionados/economia , Reembolso de Seguro de Saúde/economia , Radiologia/economia , Tomografia Computadorizada por Raios X/economia , União Europeia , Alemanha
6.
Biochim Biophys Acta ; 1842(7): 945-58, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24583340

RESUMO

Podocytes are terminally differentiated cells of the glomerular filtration barrier that react with hypertrophy in the course of injury such as in membranous nephropathy (MGN). The neuronal deubiquitinase ubiquitin C-terminal hydrolase L1 (UCH-L1) is expressed and activated in podocytes of human and rodent MGN. UCH-L1 regulates the mono-ubiquitin pool and induces accumulation of poly-ubiquitinated proteins in affected podocytes. Here, we investigated the role of UCH-L1 in podocyte hypertrophy and in the homeostasis of the hypertrophy associated "model protein" p27(Kip1). A better understanding of the basic mechanisms leading to podocyte hypertrophy is crucial for the development of specific therapies in MGN. In human and rat MGN, hypertrophic podocytes exhibited a simultaneous up-regulation of UCH-L1 and of cytoplasmic p27(Kip1) content. Functionally, inhibition of UCH-L1 activity and knockdown or inhibition of UCH-L1 attenuated podocyte hypertrophy by decreasing the total protein content in isolated glomeruli and in cultured podocytes. In contrast, UCH-L1 levels and activity increased podocyte hypertrophy and total protein content in culture, specifically of cytoplasmic p27(Kip1). UCH-L1 enhanced cytoplasmic p27(Kip1) levels by nuclear export and decreased poly-ubiquitination and proteasomal degradation of p27(Kip1). In parallel, UCH-L1 increased podocyte turnover, migration and cytoskeletal rearrangement, which are associated with known oncogenic functions of cytoplasmic p27(Kip1) in cancer. We propose that UCH-L1 induces podocyte hypertrophy in MGN by increasing the total protein content through altered degradation and accumulation of proteins such as p27(Kip1) in the cytoplasm of podocytes. Modification of both UCH-L1 activity and levels could be a new therapeutic avenue to podocyte hypertrophy in MGN.


Assuntos
Hipertrofia/metabolismo , Nefropatias/metabolismo , Podócitos/metabolismo , Ubiquitina Tiolesterase/metabolismo , Animais , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Citoplasma/enzimologia , Citoplasma/genética , Citoplasma/metabolismo , Humanos , Hipertrofia/enzimologia , Hipertrofia/genética , Nefropatias/enzimologia , Nefropatias/genética , Masculino , Podócitos/enzimologia , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos , Ratos Sprague-Dawley , Ubiquitina Tiolesterase/genética , Ubiquitinação , Regulação para Cima/genética
7.
Neuroradiology ; 57(3): 259-67, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25404413

RESUMO

INTRODUCTION: Neurovascular compression (NVC) is the most common cause of trigeminal neuralgia (TN), leading to microstructural changes in the affected nerve detectable using diffusion tensor imaging (DTI). But TN may also emerge as a symptom of multiple sclerosis (MS). The aim of this study was to evaluate if patients with MS-related TN feature the same DTI characteristics as patients with TN caused by NVC. METHODS: Twelve patients with MS-related TN, 12 age-matched patients with NVC-related TN, and 12 healthy controls were included. Using 3T-DTI, mean fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated for each affected and contralateral trigeminal nerve in patients with MS and NVC-related TN as well as healthy controls. Furthermore, presence of NVC was evaluated for patients with TN. RESULTS: There was no significant difference concerning FA or ADC when comparing the affected and the non-affected sides in patients with MS. FA was significantly lower and ADC higher in patients with MS on the TN affected as well as on the non-affected side compared to the non-affected side of patients with idiopathic TN or healthy controls. Likewise, FA was significantly lower on the affected side compared to the non-affected side in patients with idiopathic TN or healthy controls. NVC was evident in 41.7/0% on the affected/contralateral side in MS patients and 100/8% in the patients with NVC-related TN. CONCLUSION: In patients with MS-related TN, DTI reveals microstructural changes within the trigeminal nerve not only on the affected side but also on the clinically non-affected side.


Assuntos
Imagem de Tensor de Difusão/métodos , Esclerose Múltipla/complicações , Esclerose Múltipla/patologia , Nervo Trigêmeo/patologia , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/patologia , Adulto , Idoso , Algoritmos , Feminino , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Radiologie (Heidelb) ; 64(1): 54-64, 2024 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-38155326

RESUMO

BACKGROUND: Voiding cystourethrography continues to be the gold standard in the diagnostics of a wide range of diseases of the urinary tract in children. MATERIAL AND METHODS: Indications, implementation of voiding cystourethrography in terms of preparation, materials used, dealing with the child and the parents as well as the standardized examination technique are presented. In particular, the technical aspects of fluoroscopy devices and criteria for good image quality are discussed. Case studies are used to illustrate the problems of frequent urological diseases. DISCUSSION: The three standard examinations for the detection of vesicoureteral reflux (VUR), radionuclide cystography, contrast-enhanced voiding urosonography and voiding cystourethrography are compared. Their potential for detecting VUR and additional urological pathologies is discussed in detail. Furthermore, the optimized examination technique of voiding cystourethrography is presented. The applicability of the current dose reference values of the German Federal Office for Radiation Protection (BfS) in the daily routine is discussed and the feasibility of the dose reference values is explained.


Assuntos
Proteção Radiológica , Refluxo Vesicoureteral , Criança , Humanos , Micção , Fluoroscopia/efeitos adversos , Fluoroscopia/métodos , Cistografia/métodos , Refluxo Vesicoureteral/diagnóstico por imagem
9.
Radiologe ; 53(3): 200-8, 2013 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23456041

RESUMO

STANDARD RADIOLOGICAL METHODS: High-intensity focused ultrasound (synonyms FUS and HIFU) under magnetic resonance imaging (MRI) guidance (synonyms MRgFUS and MR-HIFU) is a completely non-invasive technology for accurate thermal ablation of a target tissue while neighboring tissues and organs are preserved. METHODICAL INNOVATIONS: The combination of FUS with MRI for planning, (near) real-time monitoring and outcome assessment of treatment markedly enhances the safety of the procedure. ACHIEVEMENTS: The MRgFUS procedure is clinically established in particular for the treatment of symptomatic uterine fibroids, followed by palliative ablation of painful bone metastases. Furthermore, promising results have been shown for the treatment of adenomyosis, malignant tumors of the prostate, breast and liver and for various intracranial applications, such as thermal ablation of brain tumors, functional neurosurgery and transient disruption of the blood-brain barrier.


Assuntos
Previsões , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/tendências , Imagem por Ressonância Magnética Intervencionista/métodos , Imagem por Ressonância Magnética Intervencionista/tendências , Cirurgia Assistida por Computador/métodos , Cirurgia Assistida por Computador/tendências , Humanos
10.
Radiologe ; 53(11): 1001-8, 2013 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-24170287

RESUMO

With respect to monitoring of high intensity focused ultrasound (HIFU), synonym focused ultrasound (FUS) treatment, magnetic resonance imaging (MRI) is characterized by several advantageous properties: the precise definition and morphological characterization of the target area (before and after the intervention), the real-time visualization of the treatment effect by thermal imaging (during the intervention) and in the sense of a stereotactic system, the 3-dimensional localization of the target lesion, planning of the target volume and assessment of the achieved ablation volume (before and during the intervention). Non-enhanced T2-weighted multislice MR images are acquired for planning of the intervention. For temperature monitoring (comprising thermometry and thermodosimetry), the temperature-dependent shift of proton resonance frequency (PRFS) is most frequently employed. This method is independent of the treated tissue type or thermally induced tissue changes and facilitates a relative measurement of the temperature change based on a reference value. Future MRI applications include diffusion-weighted MRI (DWI-MRI; for the intrainterventional estimation of treatment efficacy), dynamic contrast-enhanced MRI (DCE-MRI, for the prediction of the potential and assessment of the treatment effect achieved) and motion-corrected temperature monitoring (referenceless and multibaseline thermometry).


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imageamento por Ressonância Magnética/métodos , Monitorização Intraoperatória/métodos , Cirurgia Assistida por Computador/métodos , Humanos
11.
Am J Transplant ; 12(6): 1528-40, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22642473

RESUMO

The long-term effect of conversion from calcineurin inhibitor (CNI) therapy to an mTOR inhibitor requires clarification. Following completion of the 12-month, open-label, multicenter ZEUS study, in which 300 kidney transplant recipients were randomized to continue cyclosporine (CsA) or convert to everolimus at 4.5 months posttransplant, outcomes were assessed at month 36 (n = 284; 94.7%). CNI therapy was reintroduced in 28.4% of everolimus patients by month 36. The primary efficacy endpoint, estimated glomerular filtration rate (Nankivell, ANCOVA) was significantly higher with everolimus versus the CsA group at month 24 (7.6 mL/min/1.73 m(2) , 95%CI 4.3, 11.0 mL/min/1.73 m(2) ; p < 0.001) and month 36 (7.5 mL/min/1.73 m(2) , 95%CI 3.6, 11.4 mL/min/1.73 m(2) ; p < 0.001). The incidence of biopsy-proven acute rejection from randomization to month 36 was 13.0% in the everolimus arm and 4.8% in the CsA arm (p = 0.015). Patient and graft survival, as well as incidences of malignancy, severe infections and hospitalization, were similar between groups. Kidney transplant patients who are converted from CsA to everolimus at month 4.5 and who remain on everolimus thereafter may achieve a significant improvement in renal function that is maintained to 3 years. There was a significantly higher rate of rejection in the everolimus arm but this did not exert a deleterious effect by 3 years posttransplant.


Assuntos
Ciclosporina/administração & dosagem , Imunossupressores/administração & dosagem , Sirolimo/análogos & derivados , Adolescente , Adulto , Idoso , Análise de Variância , Everolimo , Humanos , Transplante de Rim , Pessoa de Meia-Idade , Sirolimo/administração & dosagem , Adulto Jovem
12.
Internist (Berl) ; 53(12): 1420-30, 2012 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-23179596

RESUMO

Shiga toxin-associated hemolytic uremic syndrome (HUS) is an entity of thrombotic microangiopathy characterized by hemolytic anemia, thrombocytopenia, central nervous symptoms, and renal insufficiency. In May 2011, an outbreak of enterohemorrhagic Escherichia coli (EHEC; O104:H4) occurred in Northern Germany. By the end of July 2011, the outbreak was over but nearly 4000 patients had an EHEC infection, 855 cases of hemolytic-uraemic syndrome were reported to the Robert Koch Institute, and there were 35 (4.1%) deaths. Shiga toxin-induced HUS is a rare disease and no controlled clinical trials on therapeutic options are available. First analyses of this outbreak suggest that therapeutic plasma exchange, which was used in the majority of patients, had no benefit and might even be harmful. The role of eculizumab, a monoclonal antibody which inhibits the complement system, is being examined in a multicenter study: the results have not been published yet. Promising is the use of some antibiotics. This would change a paradigm that antibiotics should be avoided. Ongoing and future analyses of the epidemic should be awaited before a final recommendation regarding the different treatment strategies can be made.


Assuntos
Antibacterianos/uso terapêutico , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Síndrome Hemolítico-Urêmica/mortalidade , Síndrome Hemolítico-Urêmica/terapia , Troca Plasmática/mortalidade , Escherichia coli Shiga Toxigênica , Síndrome Hemolítico-Urêmica Atípica , Alemanha/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Fatores de Risco , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento
13.
Clin Nephrol ; 76(2): 151-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21762648

RESUMO

BACKGROUND: Minimal change disease (MCD) is one of the leading causes of nephrotic syndrome. Steroid therapy is effective in achieving remission, but relapses, steroid dependence, and steroid resistance are therapeutic challenges. The use of second-line agents such as cyclophosphamide is associated with toxicity and adverse effects. Therefore, we studied the effect of rituximab (RTX) on proteinuria in adult patients with immunosuppressive (IS)-dependent MCD. METHODS: In this single-center, prospective, open series study, 6 consecutive patients with IS-dependent MCD and frequent relapses on different IS regimens - one of them after previous RTX treatment - were included. Patients were treated with a single dose of RTX (375 mg/m²). An additional dose of RTX was administered depending on B-cell count and proteinuria. RESULTS: 5 out of 6 patients achieved complete remission at the end of the follow-up; the other patient had a partial remission. All patients are free of additional IS agents and other medications were remarkably reduced. Three patients had a relapse, which was successfully treated with a further RTX treatment. CONCLUSIONS: RTX could be an alternative in the therapy of patients with IS-dependent MCD, leading to successful cessation of other IS treatment.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Antineoplásicos/uso terapêutico , Imunossupressores/uso terapêutico , Nefrose Lipoide/tratamento farmacológico , Síndrome Nefrótica/tratamento farmacológico , Proteinúria/tratamento farmacológico , Adulto , Feminino , Humanos , Masculino , Nefrose Lipoide/imunologia , Estudos Prospectivos , Recidiva , Indução de Remissão , Rituximab , Resultado do Tratamento
14.
J Pathol ; 217(3): 452-64, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18985619

RESUMO

Glomerular epithelial cell (podocyte) injury is characterized by foot process retraction, slit diaphragm reorganization, and degradation of podocyte-specific proteins. However, the mechanisms underlying podocyte injury are largely unknown. The ubiquitin C-terminal hydrolase-L1 (UCH-L1) is a key modulator of ubiquitin modification in neurons. Like neurons, UCH-L1 expression was associated with an undifferentiated status in cultured human podocytes, whereas differentiation and arborization decreased UCH-L1 and monoUb expression. Inhibition of UCH-L1 induced time and concentration-dependent process formation with alpha-actinin-4 distribution to the cell membrane and processes. An immunohistochemical approach was used to evaluate whether UCH-L1 expression was associated with podocyte injury in 15 different human glomerular diseases. Whereas normal kidneys expressed no UCH-L1 and little ubiquitin, a subset of human glomerulopathies associated with podocyte foot process effacement (membranous nephropathy, SLE class V, FSGS) de novo expressed UCH-L1 in podocyte cell bodies, nuclei, and processes. Interestingly, UCH-L1 expression correlated with podocyte ubiquitin content and internalization of the podocyte-specific proteins nephrin and alpha-actinin-4. In contrast, minimal change glomerulonephritis, a reversible disease, demonstrated minimal UCH-L1 and ubiquitin expression with intact alpha-actinin-4 but internalized nephrin. Glomerular kidney diseases typically not associated with foot process effacement (SLE class IV, ANCA+ necrotizing GN, amyloidosis, IgA nephritis) expressed intermediate to no UCH-L1 and ubiquitin. These studies show a role for UCH-L1 and ubiquitin modification in podocyte differentiation and injury.


Assuntos
Nefropatias/metabolismo , Nefropatias/patologia , Podócitos/patologia , Ubiquitina Tiolesterase/fisiologia , Actinina/análise , Actinina/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Humanos , Imuno-Histoquímica , Proteínas de Membrana/análise , Proteínas de Membrana/metabolismo , Microscopia Confocal , Podócitos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ubiquitina/análise , Ubiquitina/metabolismo
15.
J Cell Biol ; 111(5 Pt 1): 2053-62, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2172260

RESUMO

Schwann cells synthesize both hydrophobic and peripheral cell surface heparan sulfate proteoglycans (HSPGs). Previous analysis of the kinetics of radiolabeling suggested the peripheral HSPGs are derived from the membrane-anchored forms (Carey, D., and D. Evans. 1989. J. Cell Biol. 108:1891-1897). Peripheral cell surface HSPGs were purified from phytic acid extracts of cultured neonatal rat sciatic nerve Schwann cells by anion exchange, gel filtration, and laminin-affinity chromatography. Approximately 250 micrograms of HSPG protein was obtained from 2 X 10(9) cells with an estimated recovery of 23% and an overall purification of approximately 2000-fold. SDS-PAGE analysis indicated the absence of non-HSPG proteins in the purified material. Analysis of heparinase digestion products revealed the presence of at least six core protein species ranging in molecular weight from 57,000 to 185,000. The purified HSPGs were used to produce polyclonal antisera in rabbits. The antisera immunoprecipitated a subpopulation of 35SO4-labeled HSPGs that were released from Schwann cells by incubation in medium containing phosphatidylinositol-specific phospholipase C (PI-PLC); smaller amounts of immunoprecipated HSPGs were also present in phytic acid extracts. In the presence of excess unlabeled PI-PLC-released proteins, immunoprecipitation of phytic acid-solubilized HSPGs was inhibited. SDS-PAGE analysis of proteins immunoprecipitated from extracts of [35S]methionine labeled Schwann cells demonstrated that the antisera precipitated an HSPG species that was present in the pool of proteins released by PI-PLC, with smaller amounts present in phytic acid extracts. Nitrous acid degradation of the immunoprecipitated proteins produced a single 67,000-Mr core protein. When used for indirect immunofluorescence labeling, the antisera stained the external surface of cultured Schwann cells. Preincubation of the cultures in medium containing PI-PLC but not phytic acid significantly reduced the cell surface staining. The antisera stained the outer ring of Schwann cell membrane in sections of adult rat sciatic nerve but did not stain myelin or axonal membranes. This localization suggests the HSPG may play a role in binding the Schwann cell plasma membrane to the adjacent basement membrane surrounding the individual axon-Schwann cell units.


Assuntos
Proteoglicanas de Sulfatos de Condroitina/isolamento & purificação , Heparitina Sulfato/isolamento & purificação , Células de Schwann/química , Animais , Anticorpos , Proteoglicanas de Sulfatos de Condroitina/imunologia , Imunofluorescência , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato/imunologia , Técnicas In Vitro , Microscopia de Fluorescência , Fosfatidilinositol Diacilglicerol-Liase , Fosfoinositídeo Fosfolipase C , Diester Fosfórico Hidrolases/fisiologia , Ratos , Ratos Endogâmicos , Células de Schwann/citologia , Nervo Isquiático/química , Nervo Isquiático/citologia
16.
J Cell Biol ; 124(1-2): 161-70, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8294499

RESUMO

To investigate the biological functions of transmembrane proteoglycans we have produced clonal cell lines of rat Schwann cells that express the hybrid proteoglycan syndecan-1. This was done by transfection of newborn rat Schwann cells with a plasmid vector bearing the rat syndecan-1 cDNA sequence under transcriptional control of the constitutively active cytomegalovirus promoter, and a neomycin resistance gene. Stably expressing cells were selected by growth in G418. Expression of syndecan-1 was verified by Northern and immunoblot analysis and immunoprecipitation of 35SO4-labeled proteoglycans. The syndecan-1 expressing cells exhibited significantly enhanced spreading on several different substrata, including fibronectin and laminin, and an altered morphology. The enhanced spreading appeared to result from the presence of syndecan-1, based on the observation that anti-syndecan-1 antibodies inhibited the enhanced substratum spreading. There was also a reorganization of cytoskeletal structures and formation of focal adhesions, visualized by anti-vinculin staining, which were absent from control Schwann cells. There was no apparent stable association of cell surface syndecan-1 with focal contact sites, as determined by dual staining with anti-syndecan-1 and anti-vinculin antibodies. Colocalization of patches of cell surface syndecan-1 with actin was observed, but only during cell spreading. These findings provide evidence for a role of transmembrane proteoglycans in cellular morphogenesis, and suggest that transient association of syndecans with microfilaments may be an important aspect of their biological function.


Assuntos
Actinas/metabolismo , Adesão Celular , Citoesqueleto/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteoglicanas/metabolismo , Células de Schwann/metabolismo , Animais , Animais Recém-Nascidos , Compartimento Celular , Células Cultivadas , Citoesqueleto/ultraestrutura , Imunofluorescência , Proteínas dos Microfilamentos/metabolismo , Ratos , Sindecana-1 , Sindecanas , Transfecção , Vinculina/metabolismo
17.
J Cell Biol ; 117(1): 191-201, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1556152

RESUMO

A cDNA clone coding for a membrane proteoglycan core protein was isolated from a neonatal rat Schwann cell cDNA library by screening with an oligonucleotide based on a conserved sequence in cDNAs coding for previously described proteoglycan core proteins. Primer extension and polymerase chain reaction amplification were used to obtain additional 5' protein coding sequences. The deduced amino acid sequence predicted a 353 amino acid polypeptide with a single membrane spanning segment and a 34 amino acid hydrophilic COOH-terminal cytoplasmic domain. The putative extracellular domain contains three potential glycosaminoglycan attachment sites, as well as a domain rich in Thr and Pro residues. Analysis of the cDNA and deduced amino acid sequences revealed a high degree of identity with the transmembrane and cytoplasmic domains of previously described proteoglycans but a unique extracellular domain sequence. On Northern blots the cDNA hybridized to a single 5.6-kb mRNA that was present in Schwann cells, neonatal rat brain, rat heart, and rat smooth muscle cells. A 16-kD protein fragment encoded by the cDNA was expressed in bacteria and used to immunize rabbits. The resulting antibodies reacted on immunoblots with the core protein of a detergent extracted heparan sulfate proteoglycan. The core protein had an apparent mass of 120 kD. When the anti-core protein antibodies were used to stain tissue sections immunoreactivity was present in peripheral nerve, newborn rat brain, heart, aorta, and other neonatal tissues. A ribonuclease protection assay was used to quantitate levels of the core protein mRNA. High levels were found in neonatal rat brain, heart, and Schwann cells. The mRNA was barely detectable in neonatal or adult liver, or adult brain.


Assuntos
Heparitina Sulfato/genética , Glicoproteínas de Membrana/genética , Proteoglicanas/genética , Envelhecimento , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Sequência de Bases , Northern Blotting , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Clonagem Molecular/métodos , DNA/genética , DNA/isolamento & purificação , Embrião de Mamíferos , Imunofluorescência , Biblioteca Gênica , Proteoglicanas de Heparan Sulfato , Humanos , Fígado/crescimento & desenvolvimento , Fígado/fisiologia , Glicoproteínas de Membrana/análise , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Proteoglicanas/análise , RNA Mensageiro/genética , Ratos , Células de Schwann/fisiologia , Homologia de Sequência do Ácido Nucleico , Sindecanas , Transcrição Gênica
18.
Science ; 220(4599): 862-5, 1983 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-6601822

RESUMO

The acquired immune deficiency syndrome (AIDS) is characterized by T-lymphocyte dysfunction and is frequently accompanied by opportunistic infections and Kaposi's sarcoma. Human T-cell leukemia virus (HTLV) is associated with T-cell malignancies and can transform T lymphocytes in vitro. In an attempt to find evidence of HTLV infection in patients with AIDS, DNA from samples of peripheral blood lymphocytes from 33 AIDS patients was analyzed by Southern blot-hybridization with a radiolabeled cloned HTLV DNA probe. Analysis of DNA from both the fresh (uncultured) lymphocytes and from T cells cultured with T-cell growth factor revealed the presence of integrated HTLV proviral sequences in lymphocytes from two of the patients, both of whom had antibody to HTLV. The proviral sequences could not be detected in blood samples obtained from these individuals at a later date, consistent with the possibility that the population of infected cells had become depleted.


Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , DNA Viral/análise , Retroviridae , Infecções Tumorais por Vírus/microbiologia , Síndrome da Imunodeficiência Adquirida/etiologia , Síndrome da Imunodeficiência Adquirida/imunologia , Adulto , Animais , Gatos , Humanos , Masculino , Pessoa de Meia-Idade , Retroviridae/genética , Linfócitos T/análise , Linfócitos T/microbiologia , Infecções Tumorais por Vírus/complicações
19.
Science ; 220(4599): 865-7, 1983 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-6601823

RESUMO

Several isolates of a human type-C retrovirus belonging to one group, known as human T-cell leukemia virus (HTLV), have previously been obtained from patients with adult T-cell leukemia or lymphoma. The T-cell tropism of HTLV and its prevalence in the Caribbean basin prompted a search for it in patients with the epidemic T-cell immune deficiency disorder known as AIDS. Peripheral blood lymphocytes from one patient in the United States and two in France were cultured with T-cell growth factor (TCGF) an shown to express HTLV antigens. Virus from the U.S. patient was isolated and characterized and shown to be related to HTLV subgroup I. The virus was also transmitted into normal human T cells from umbilical cord blood of a newborn. Whether or not HTLV-I or other retroviruses of this family with T-cell tropism cause AIDS, it is possible that patients from whom the virus can be isolated can also transmit it to others. If the target cell of AIDS is the mature T cell as suspected, the methods used in these studies may prove useful for the long-term growth of these cells and for the identification of antigens specific for the etiological agent of AIDS.


Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Retroviridae/isolamento & purificação , Infecções Tumorais por Vírus/microbiologia , Síndrome da Imunodeficiência Adquirida/etiologia , Síndrome da Imunodeficiência Adquirida/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Feminino , Humanos , Imunidade Celular , Masculino , Linfócitos T/microbiologia , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/transmissão
20.
J Vet Pharmacol Ther ; 32(4): 388-92, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19614844

RESUMO

Phenylbutazone (PBZ) is a nonsteroidal anti-inflammatory drug used in the treatment of chronic pain and arthritis. Topical and transdermal administration of PBZ would be beneficial in large animals in terms of minimizing gastro-intestinal ulcerations and other side effects, easy administration to legs and joints and minimizing the dose to reduce systemic toxicity of the drug. A topical liposomal preparation with different concentrations of a mono-substituted alkyl amide (MSA) and PBZ was formulated. The formulations were evaluated by in vitro skin-permeation kinetics through deer skin using Franz diffusion cells. By increasing drug loading from 1% to 5% w/w, the steady-state flux (microg/cm(2)/h) of PBZ was increased twofold (P < 0.001). Similarly, by increasing the MSA concentration from 0% to 4%, the steady-state flux (microg/cm(2)/h) of PBZ was increased twofold (P < 0.001). Overall, by increasing the drug load and the use of an appropriate amount of the penetration enhancer, the steady-state flux of PBZ through skin was increased fourfold (P < 0.001). MSA at both 2% and 4% w/w concentrations significantly increased the skin levels of PBZ as compared with control (P < 0.05). In conclusion, MSA served as an effective skin-penetration enhancer in the liposomal gel of PBZ for deer.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Fenilbutazona/administração & dosagem , Absorção Cutânea/efeitos dos fármacos , Administração Cutânea , Análise de Variância , Animais , Anti-Inflamatórios não Esteroides/metabolismo , Cromatografia Líquida de Alta Pressão/veterinária , Cervos , Géis , Lipossomos , Fenilbutazona/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA