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1.
Commun Biol ; 6(1): 217, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36823431

RESUMO

Tissue mechanics determines tissue homeostasis, disease development and progression. Bladder strongly relies on its mechanical properties to perform its physiological function, but these are poorly unveiled under normal and pathological conditions. Here we characterize the mechanical fingerprints at the micro-scale level of the three tissue layers which compose the healthy bladder wall, and identify modifications associated with the onset and progression of pathological conditions (i.e., actinic cystitis and bladder cancer). We use two indentation-based instruments (an Atomic Force Microscope and a nanoindenter) and compare the micromechanical maps with a comprehensive histological analysis. We find that the healthy bladder wall is a mechanically inhomogeneous tissue, with a gradient of increasing stiffness from the urothelium to the lamina propria, which gradually decreases when reaching the muscle outer layer. Stiffening in fibrotic tissues correlate with increased deposition of dense extracellular matrix in the lamina propria. An increase in tissue compliance is observed before the onset and invasion of the tumor. By providing high resolution micromechanical investigation of each tissue layer of the bladder, we depict the intrinsic mechanical heterogeneity of the layers of a healthy bladder as compared with the mechanical properties alterations associated with either actinic cystitis or bladder tumor.


Assuntos
Cistite , Neoplasias da Bexiga Urinária , Ratos , Animais , Bexiga Urinária , Cistite/patologia , Matriz Extracelular , Neoplasias da Bexiga Urinária/patologia
2.
Arq. bras. med. vet. zootec. (Online) ; 70(3): 857-872, maio-jun. 2018. ilus, tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-911635

RESUMO

Com o objetivo de estudar o efeito da condroitinase associada às células-tronco mesenquimais na lesão aguda da medula espinhal, utilizaram-se 50 ratos Lewis, distribuídos igualmente nos grupos: controle negativo (CN), tratamento com placebo (PLA), condroitinase (CDN), células-tronco mesenquimais (CTM) e condroitinase mais células-tronco mesenquimais (CDN+CTM). Todos os animais tiveram a medula espinhal exposta por laminectomia, e os grupos PLA, CDT, CTM e CDT+CTM sofreram também trauma medular compressivo. Após sete dias, procedeu-se à reexposição da medula espinhal, quando os grupos PLA e CTM receberam 4µL de líquido cefalorraquidiano artificial via intralesional, e os grupos CDT e CDT+CTM receberam o mesmo líquido contendo 2,2U de condroitinase. Após 14 dias da cirurgia inicial, todos os animais receberam 0,2mL de PBS via endovenosa, contudo, nos grupos CTM e CDT+CTM, esse líquido continha 1x106 CTM. Avaliou-se a capacidade motora até o 28o dia pós-trauma e, posteriormente, as medulas espinhais foram analisadas por RT-PCR, para quantificação da expressão gênica para BDNF, NT-3, VEGF, KDR e PECAM-1, e por imunoistoquímica, para detecção das células-tronco GFP injetadas (anti-GFP), quantificação dos neurônios (anti-NeuN) e da GFAP e vimentina, para avaliação da cicatriz glial. As análises estatísticas foram realizadas com o auxílio do Prism 5 for Windows, com o nível de significância de 5%. Não houve diferença entre os grupos quanto à capacidade motora. O grupo CDT+CTM apresentou maior imunoexpressão de neurônios viáveis do que o placebo. No CTM, houve maior expressão dos fatores neurotróficos BDNF e VEGF. E no CDT, houve menor imunoexpressão de vimentina. Concluiu-se que a associação CDT+CTM favorece a viabilidade neuronal após o trauma, que o tratamento com CTM promove aumento na expressão dos fatores tróficos BDNF e VEGF e que o tratamento com condroitinase é efetivo na redução da cicatriz glial.(AU)


The aim of this work was to study the effect of chondroitinase associated with mesenchymal stem cells in acute spinal cord injury. Therefore, 50 Lewis rats were distributed in the following groups: negative control (NC), treatment with placebo (PLA), chondroitinase (CDT), mesenchymal stem cells (MSC), and chondroitinase associated with mesenchymal stem cells (CDT + MSC). All animals had their spinal cord exposed by laminectomy, and the groups named PLA, CDT, MSC and CDT + MSC also suffered compressive spinal cord trauma. After seven days, the spinal cord was re-exposed, when the PLA and MSCs groups received 4uL of artificial cerebrospinal fluid through the lesion, and the CDT group and CDT + MSC received the same fluid containing 2,2U of chondroitinase. 14 days after the first surgery, all animals received 0.2ml of PBS intravenously; however, the MSC and CDT + MSC groups received the same liquid also containing 1x106 MSCs. The motor skills were evaluated up to 28 days post-injury and, subsequently, the spinal cords were analyzed by RT-PCR for BDNF, NT-3, VEGF, PECAM-1 and KDR gene expression quantification, immunohistochemistry to detect injected stem cells GFP (anti-GFP), to quantify neurons (anti-NeuN), GFAP and detect vimentin in order to evaluate the glial scar. Statistical analyzes were performed by Prism 5 for Windows using a 5% level of significance. There was no difference between groups with regarding motor capacity. The CDT + MSC group showed increased immunoreactivity of viable neurons than placebo. In MSC, there was a greater expression of neurotrophic factors BDNF and VEGF. Also, there was less vimentin immunostaining in group CDT. It was concluded that CDT + MSC association promotes neuronal viability after trauma, in which treatment with MSC promotes increased expression of BDNF and VEGF trophic factors, and also that treatment with chondroitinase is effective in reducing the glial scar.(AU)


Assuntos
Animais , Ratos , Condroitina ABC Liase , Ratos/anatomia & histologia , Ratos/lesões , Células-Tronco Mesenquimais/enzimologia
3.
Leukemia ; 31(8): 1735-1742, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28025584

RESUMO

Immunoglobulin light chain (AL) amyloidosis is characterized by tissue deposition of amyloid fibers derived from immunoglobulin light chain. AL amyloidosis and multiple myeloma (MM) originate from monoclonal gammopathy of undetermined significance. We wanted to characterize germline susceptibility to AL amyloidosis using a genome-wide association study (GWAS) on 1229 AL amyloidosis patients from Germany, UK and Italy, and 7526 healthy local controls. For comparison with MM, recent GWAS data on 3790 cases were used. For AL amyloidosis, single nucleotide polymorphisms (SNPs) at 10 loci showed evidence of an association at P<10-5 with homogeneity of results from the 3 sample sets; some of these were previously documented to influence MM risk, including the SNP at the IRF4 binding site. In AL amyloidosis, rs9344 at the splice site of cyclin D1, promoting translocation (11;14), reached the highest significance, P=7.80 × 10-11; the SNP was only marginally significant in MM. SNP rs79419269 close to gene SMARCD3 involved in chromatin remodeling was also significant (P=5.2 × 10-8). These data provide evidence for common genetic susceptibility to AL amyloidosis and MM. Cyclin D1 is a more prominent driver in AL amyloidosis than in MM, but the links to aggregation of light chains need to be demonstrated.


Assuntos
Amiloidose/genética , Estudo de Associação Genômica Ampla , Cadeias Leves de Imunoglobulina/metabolismo , Mieloma Múltiplo/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Ciclina D1/fisiologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
4.
Leukemia ; 28(12): 2311-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25059496

RESUMO

Oral melphalan and dexamethasone (MDex) is a standard treatment for patients with AL amyloidosis who are not eligible for stem cell transplantation at many referral centers. However, following encouraging reports on the activity of bortezomib combined with alkylators and dexamethasone, these combinations are being moved to frontline therapy. We compared the outcome of 87 patients treated with bortezomib plus MDex (BMDex) with that of 87 controls treated with MDex. Patients and controls were matched for age, cardiac and renal function and free light chain burden. A higher rate of complete responses was observed with BMDex (42 vs 19%), but this did not result in a survival improvement in the overall population. However, a significant survival advantage for BMDex was observed in patients without severe (New York Heart Association class III or IV) heart failure and with N-terminal pro-natriuretic peptide type-B <8500 ng/l. Patients treated with full-dose dexamethasone had similar response rates and survival whether they received bortezomib or not. Intermediate-risk patients who are not fit enough to receive high-dose dexamethasone are likely to take the greatest advantage from the addition of bortezomib to MDex.


Assuntos
Amiloidose/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Idoso , Amiloidose/diagnóstico , Amiloidose/metabolismo , Amiloidose/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ácidos Borônicos/administração & dosagem , Bortezomib , Estudos de Casos e Controles , Dexametasona/administração & dosagem , Humanos , Cadeias Leves de Imunoglobulina/metabolismo , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Pirazinas/administração & dosagem , Resultado do Tratamento
5.
Nanotechnology ; 23(47): 475101, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23111156

RESUMO

Nanostructured cubic zirconia is a strategic material for biomedical applications since it combines superior structural and optical properties with a nanoscale morphology able to control cell adhesion and proliferation. We produced nanostructured cubic zirconia thin films at room temperature by supersonic cluster beam deposition of nanoparticles produced in the gas phase. Precise control of film roughness at the nanoscale is obtained by operating in a ballistic deposition regime. This allows one to study the influence of nanoroughness on cell adhesion, while keeping the surface chemistry constant. We evaluated cell adhesion on nanostructured zirconia with an osteoblast-like cell line using confocal laser scanning microscopy for detailed morphological and cytoskeleton studies. We demonstrated that the organization of cytoskeleton and focal adhesion formation can be controlled by varying the evolution of surface nanoroughness.


Assuntos
Materiais Biocompatíveis/química , Adesão Celular , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Osteoblastos/citologia , Zircônio/química , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Humanos , Propriedades de Superfície
7.
Neurol Sci ; 32(5): 801-10, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21487761

RESUMO

Low-grade gliomas are slow-growing tumors invading eloquent areas and white matter pathways. For many decades these tumors were considered inoperable because of their high tropism for eloquent areas. However, the young age of the patients and the inescapable anaplastic transformation have recently suggested more aggressive treatments. We analyzed the neurological and neuro-oncological outcome of 12 patients who underwent surgery fully awake for the resection of LGG, harboring eloquent areas. 10 right- and 2 left-handed patients underwent pre-operative assessment: Karnofsky Performance Status, Edinburgh Handedness Inventory Score; neuropsychological and neurophysiological evaluations, according to the tumor location. During surgery we performed: sensory-motor-evoked potentials, continuous electro-corticography and bipolar/monopolar cortico-subcortical mapping during neuropsychological tests. The resection rate was calculated with neuro-imaging elaboration software. No permanent post-operative deficits were reported; 2 patients improved after surgery. No impairment of cognitive functions was reported. The KPS improved in 8 patients and was steady in the others. The mean resection rate was 78.3%. The resection allowed the control of pre-operative seizures without increasing the drug intake. Awake surgery allowed a good resection rate despite the eloquent location of the tumors, without post-operative deficit. The neuropsychological outcome was unchanged after surgery. The resection seems to improve seizure control. All the patients came back to normal life and work. In conclusion, awake surgery is reliable and feasible in removal of LGG, even if invading the main eloquent areas and networks. All the patients experienced a normal life after surgery, without permanent deficits.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Procedimentos Neurocirúrgicos/métodos , Vigília , Adulto , Mapeamento Encefálico , Neoplasias Encefálicas/patologia , Estimulação Elétrica , Feminino , Seguimentos , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Testes Neuropsicológicos , Período Pós-Operatório , Resultado do Tratamento
8.
J Nanosci Nanotechnol ; 6(4): 1140-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16736779

RESUMO

This study intends to explain the fluid dynamic characteristics of a Pulsed Microplasma Cluster Source (PMCS). An axially symmetric steady state simulation is performed for modeling the real-life three-dimensional unsteady flow of hypersonic helium inside our PMCS. Hypersonic helium flow is simulated using Realizable k-epsilon turbulent model. We obtained the jet velocity, density, and pressure field inside our PMCS for the conditions considered and discussed them with respect to our experimental observations. We also presented a qualitative discussion on the formation-termination process of this hypersonic jet. In particular, simulation, in agreement with the experiment, indicates that the middle stage of the injection process, where the Mach disk stands close to the ablation target and at the same time the mass flow rate is relatively high, is almost the appropriate time for firing the electric discharge. We simulated the jet-electrode impingement and tracked the trajectory of the ablated carbon clusters, considered as rigid spheres, inside the PMCS. We noticed that the spatial distribution of the clusters inside PMCS is highly conserved during the free expansion of the cluster beam out of the nozzle (in the vacuum chambers) and is recognizable in the deposited carbon film. This indicates that the geometry of PMCS plays a significant role in the uniformity of the deposited film.


Assuntos
Gases/química , Hélio/química , Temperatura Alta , Membranas Artificiais , Modelos Químicos , Modelos Moleculares , Nanoestruturas/química , Simulação por Computador , Análise de Injeção de Fluxo/instrumentação , Análise de Injeção de Fluxo/métodos , Teste de Materiais , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Tamanho da Partícula
9.
Eur J Ophthalmol ; 16(2): 295-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16703549

RESUMO

PURPOSE: To evaluate the efficacy and clinical effects of local retrobulbar anesthesia using ropivacaine in vitreoretinal surgery. METHODS: Prospective study. A total of 919 vitreoretinal operations were followed. The operations were divided into three groups, depending on the degree of anesthesia needed. Group A: Vitrectomies with episcleral procedures (208 vitrectomies for detached retina or perforating trauma). Group B: Episcleral procedures only (410 operations for detached retina without vitrectomy). Group C: Vitrectomies without episcleral surgery (301 operations for macular pucker or hole, proliferative diabetic retinopathy, or silicone oil removal). Anesthesia was administered using a 23-gauge Atkinson-type retrobulbar needle, after topical anesthesia. Six mL of the solution containing 7.5 mg ropivacaine/mL were injected into the peribulbar space, and the other 4 mL deeper, into the retrobulbar space. The degree of infiltration of the palpebral region, the motor block in the extrinsic ocular muscles, and pain felt were checked and rated. RESULTS: Swelling of lids was seen in 885 patients (96%); in 21 (2%) swelling was partial. In 13 patients (1%) there were no signs of infiltration. The motor block was total in 801 (87%) eyes, while 118 (12%) had reduced ocular movements. The degree of anesthesia was as follows, considering the three groups together: no pain = 855 (93%) patients; moderate pain = 44 (4%) patients; very strong pain = 20 (2%) patients. No adverse events or side effects were observed. CONCLUSIONS: Ropivacaine used for retrobulbar-peribulbar combined anesthesia in vitreoretinal surgery showed excellent clinical efficacy as regards analgesia and muscle akinesia.


Assuntos
Amidas/administração & dosagem , Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Músculos Oculomotores/efeitos dos fármacos , Órbita/efeitos dos fármacos , Doenças Retinianas/cirurgia , Vitrectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Amidas/efeitos adversos , Analgesia , Anestésicos Locais/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Junção Neuromuscular/efeitos dos fármacos , Medição da Dor , Estudos Prospectivos , Ropivacaina
11.
J Microsc ; 215(Pt 3): 236-40, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15312188

RESUMO

Analyses of individual biomolecules, like DNA, or DNA-protein complexes, via atomic force microscopy, require 'gentle' methods to immobilize DNA on surfaces, which allow the ensemble of molecules to adopt conformations dictated primarily by their physical characteristics, and which possibly permit the use of a wide selection of buffers. We show that poly-L-ornithine-coated mica is a good substrate for fast, reliable deposition of DNA for wet or dry imaging. The surface firmly secures DNA, which retains the B-form helical rise (0.34 nm bp(-1)). The conformations of DNA that result are reminiscent of three-dimensional random coils projected on to a plane. The contrast is good, especially in solution, and buffers with physiological concentrations of salt with or without divalent cations may be used. This is important for comparison of scanning probe microscopy results with those obtained by different techniques.


Assuntos
Silicatos de Alumínio/química , DNA/química , Microscopia de Força Atômica/métodos , Peptídeos/química , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Fatores de Transcrição SOX
12.
Parkinsonism Relat Disord ; 10(4): 247-51, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15120100

RESUMO

We describe a patient with Parkinson's Disease who underwent bilateral subthalamic nucleus deep brain stimulation and later presented with episodes of aggressive behavior disorder with disturbed impulse control and an inability to control anger likely related to the deep brain stimulation "switch-on stimulation". We hypothesize that increasing voltage intensity could influence neighboring passing fibers coming from basal limbic system that are involved in the regulation of affect and emotional behavior. We suggest investigating these neuropsychological disturbances considering their influence on quality of life after surgery.


Assuntos
Agressão/psicologia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/psicologia , Terapia por Estimulação Elétrica/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Doença de Parkinson/psicologia , Doença de Parkinson/cirurgia , Núcleo Subtalâmico
13.
Phys Rev Lett ; 65(4): 488-491, 1990 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-10042933
14.
Phys Rev Lett ; 63(26): 2834-2836, 1989 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-10041005
15.
Eur J Obstet Gynecol Reprod Biol ; 26(2): 145-50, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3666271

RESUMO

Cytogenetic data represent a first line diagnostic aid in gonadal dysgenesis. Generally, the results of a peripheral blood examination reflect the genotypic alteration of the patient. Nevertheless, on occasion one may encounter cases in which clinical and hormonal evidence suggestive of dysgenesis is not accompanied by an anomalous chromosomal finding, upon cytogenetic analysis of the peripheral blood. In these cases, a cytogenetic alteration may be present in cellular components of the ovary and the cutis. In the light of the above, two patients presenting with primary hypergonadotropic amenorrhea, streak gonads and normal peripheral karyotype are described. In one patient presenting with phenotype alterations, ovarian wedge biopsy via laparotomy followed by cytogenetic analysis of ovarian tissue and tissue from the cutis revealed a 45,X/46,XX-type mosaicism. In the other patient, the ovarian cytogenetic findings were unremarkable. Extending chromosomal analysis to several tissues, beyond the peripheral level, in selected cases, is discussed.


Assuntos
Amenorreia/diagnóstico , Disgenesia Gonadal/complicações , Linfócitos/ultraestrutura , Adolescente , Adulto , Amenorreia/genética , Feminino , Fibroblastos/ultraestrutura , Disgenesia Gonadal/genética , Humanos , Cariotipagem , Mosaicismo , Ovário/ultraestrutura , Cromossomo X/ultraestrutura
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