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1.
Complement Ther Med ; 33: 72-77, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28735829

RESUMO

BACKGROUND: Pilates method has been recommended for patients with chronic low back pain (CLBP) and the activation of transversus abdominis has been deemed to play an important role in the improvement of these patients. Nevertheless, the evidence of the activation of TrA in Pilates practitioners remains unclear. OBJECTIVE: To assess the effectiveness of 12 weeks of Pilates practice in disability, pain, kinesiophobia and transversus abdominis activation in patients with chronic nonspecific Low Back Pain. DESIGN: A randomized controlled trial was carried out. METHODS: A single-blind randomized controlled trial with repeated measures at 6 and 12 weeks was carried out. A total of ninety eight patients with low back pain were included and randomly allocated to a Pilates Mat group (PMG) equipment based with apparatus Pilates (PAG) or control group (CG). Roland Morris Disability Questionnaire (RMDQ), visual analog scale (VAS) Tampa Scale of Kinesiophobia (TSK), and transversus abdominis (TrA) activation assessed by real time ultrasound measurement (US) were assessed as outcome measures. RESULTS: Improvement were observed in both intervention groups in all the included variables at 6 and 12 weeks (p<0.001). Faster enhancement was observed in the equipment based Pilates group (p=0.007). CONCLUSIONS: Equipment based and mat Pilates modalities are both effective in the improvement of TaA activation in patients with CLBP with associate improvement on pain, function and kinesiophobia. Significant differences were observed after 12 weeks of intervention in PMG and PAG with faster improvement in PAG suggesting that, feedback provided by equipment could help in the interiorization of Pilates principles.


Assuntos
Músculos Abdominais/fisiologia , Dor Crônica/terapia , Técnicas de Exercício e de Movimento/métodos , Terapia por Exercício , Medo , Dor Lombar/terapia , Atividade Motora , Atividades Cotidianas , Adulto , Dor Crônica/psicologia , Avaliação da Deficiência , Equipamentos e Provisões , Feminino , Humanos , Dor Lombar/psicologia , Masculino , Pessoa de Meia-Idade , Contração Muscular , Dor , Método Simples-Cego , Ultrassonografia , Adulto Jovem
2.
Gait Posture ; 55: 116-120, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28437758

RESUMO

Kidney transplant recipients (KTRs) present with compromised functional capacity, low levels of physical activity, muscle atrophy, and peripheral nerve dysfunction that may result in high postural instability. This study aimed to compare the static balance control of 19 KTRs with 19 healthy adults (HA). All participants completed the Romberg test on a stabilometric platform with eyes open (EO), eyes closed (EC) and during a dual task (DT) condition. Centre of pressure (COP) measures (COP velocity (COPv) and sway area (SA)), as well as position-based outcomes such as anterior-posterior (AP) and medio-lateral (ML) ranges of COP displacements were recorded. Independent ANCOVA revealed an overall lower performance of KTRs compared to HA (p<0.05) with the EC condition exhibiting the worst relative performance for KTRs, suggesting a poorer capacity of relying on proprioceptive information when maintaining the upright posture. The addition of a cognitive task did not further worsen balance performance in KTRs. As impaired postural control is one of the main predictors of falls in elderly subjects, these data might also indicate that this constitutes an equivalent risk factor for falling in middle-aged KTRs.


Assuntos
Falência Renal Crônica/fisiopatologia , Transplante de Rim , Transtornos dos Movimentos/fisiopatologia , Equilíbrio Postural/fisiologia , Adulto , Idoso , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/cirurgia , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/etiologia , Doenças do Sistema Nervoso Periférico , Fatores de Risco
3.
Age (Dordr) ; 37(6): 118, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26578458

RESUMO

Participation in exercise programs is heartily recommended for older adults since the level of physical fitness directly influences functional independence. The aim of this present study was to investigate the effects of supervised Pilates exercise training on the physical function, hypothesizing that a period of Pilates exercise training (PET) can increase overall muscle strength, body composition, and balance, during single and dual-task conditions, in a group of post-menopausal women. Twenty-five subjects, aged 59 to 66 years old, were recruited. Eligible participants were assessed prior and after 3 months of PET performed twice per week. Muscular strength was evaluated with handgrip strength (HGS) test, 30-s chair sit-to-stand test (30CST), and abdominal strength (AST) test. Postural control and dual-task performance were measured through a stabilometric platform while dynamic balance with 8 ft up and go test. Finally, body composition was assessed by means of dual-energy X-ray absorptiometry. Statistically significant improvements were detected on HGS (+8.22%), 30CST (+23.41%), 8 ft up and go test (-5.95%), AST (+30.81%), medio-lateral oscillations in open eyes and dual-task condition (-22.03% and -10.37%). Pilates was effective in increasing upper body, lower body, and abdominal muscle strength. No changes on body composition were detected. Results on this investigation indicated also that 12-week of mat Pilates is not sufficient to determine a clinical meaningful improvement on static balance in single and dual-task conditions.


Assuntos
Composição Corporal/fisiologia , Técnicas de Exercício e de Movimento/métodos , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Força Muscular/fisiologia , Projetos Piloto , Pós-Menopausa , Equilíbrio Postural/fisiologia , Resultado do Tratamento
4.
Prev Med ; 75: 1-11, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25773473

RESUMO

UNLABELLED: This systematic review aims to summarize the effects of Pilates exercise training (PET) in elderly population on physical fitness, balance and fall prevention, and its effects on mood states, quality of life and independence in the daily living activities. METHODS: Keyword "Pilates" associated with "elderly", "aging" and "old subjects" were identified as terms for the literature research in MEDLINE, Embase, PubMed, Scopus, PsycINFO and SPORTDiscus. Only studies published in peer-reviewed journals written in English language were considered. A meta-analysis was performed and effect sizes (ES) calculated. RESULTS: 10 studies were identified (6 RCTs and 4 uncontrolled trials); age ranged from 60 to 80years. Overall, PET showed large ES to improve muscle strength (ES=1.23), walking and gait performances (ES=1.39), activities of daily living, mood states and quality of life (ES=0.94), moderate to high effect on dynamic balance (ES=0.77), small effects on static balance (ES=0.34) and flexibility (ES=0.31), while a small effect on cardio-metabolic outcomes (ES=0.07). CONCLUSIONS: PET should be taken into account as a way to improve quality of life in the elderly, due to the imparted benefits of fall prevention, physical fitness, and mood states. In this context, physicians might include PET as a tool for exercise prescriptions for the elderly.


Assuntos
Técnicas de Exercício e de Movimento , Exercício/fisiologia , Aptidão Física/fisiologia , Acidentes por Quedas/prevenção & controle , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Equilíbrio Postural , Qualidade de Vida , Caminhada/fisiologia
5.
Arq. bras. med. vet. zootec ; 65(6): 1759-1766, Dec. 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-696859

RESUMO

The aim of this study was to evaluate the nutritional value of three sorghum cultivars with different concentrations of condensed tannins in sheep diets. Six adult sheep (LW=56kg) with rumen and duodenal fistulas were assigned to experimental groups using two 3x3 Latin Square designs. The diets were formulated using three sorghum cultivars: LTC (low-tannin cultivar), MTC (medium-tannin cultivar) and HTC (high-tannin cultivar). Microbial nitrogen (MN) concentration in the duodenum was measured using a 15N trace technique. LTC, MTC and HTC diets presented values of 788, 722 and 747 (SE=20.6) g kg-1 for dry matter digestibility and 633, 535 and 530 (SE=35.8) g/kg for crude protein digestibility. The LTC diet was significantly different from the other diets (P<0.05). The nitrogen balance was 145.5, 94.8 and 83.8g kg-1 (SE=13.0) for LTC, MTC and HTC, respectively, with LTC showing greater nitrogen retention (P<0.05). Values obtained for MN in the digesta were 301, 364 and 469 (SE=30.6) g kg-1 for LTC, MTC and HTC, respectively, and there was no statistical difference (P>0.05) between the diets. The presence of condensed tannins in the sorghum interfered with the sheep's nitrogen retention; however, the microbial protein supply to the duodenum of the animals was not inhibited.


O objetivo do presente estudo foi avaliar o valor nutricional de três cultivares de sorgo com diferentes concentrações de tanino condensado em dietas de ovinos. Seis carneiros machos, adultos, castrados, canulados no rúmen e duodeno foram divididos em três grupos experimentais, em um delineamento em quadrado latino 3x3. Os tratamentos foram representados por três dietas experimentais contendo diferentes cultivares de grão de sorgo: LTC (cultivar com baixa concentração de tanino), MTC (cultivar com concentração média de tanino) e HTC (cultivar com concentração alta de tanino). As concentrações de nitrogênio de origem microbiana no duodeno (MN) foram mensuradas pela técnica de marcador isótopo estável 15N. As dietas LTC, MTC e HTC apresentaram valores de 788, 722 e 747g.kg-1 (EP=20,6) para a digestibilidade aparente da matéria seca e 633, 535 e 530g.kg-1 (EP=35,8) para a digestibilidade aparente da proteína bruta. A dieta LTC apresentou diferença significativa quando comparada às demais dietas para as avaliações de digestibilidade (P<0,05). Os valores encontrados para o balanço de nitrogênio foram de 145,5; 94,8 e 83,8g.kg-1 (EP=13,0) para LTC, MCT e LTC, respectivamente, sendo a dieta LTC a que apresentou maior retenção de nitrogênio (P<0,05). Os valores obtidos para MN na digesta foram de 301, 364 e 469 para LTC, MTC e HTC, respectivamente, e não apresentaram diferenças estatísticas (P>0,05). As diferentes concentrações de taninos condensados nos cultivares de sorgo resultaram em melhorias na digestibilidade e retenção de nitrogênio das dietas, entretanto o fluxo de proteína microbiana não foi inibido.


Assuntos
Animais , Imunidade Humoral/fisiologia , Metodologia , Peixes/classificação
6.
Pathologica ; 104(3): 98-100, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22931040

RESUMO

OBJECTIVE: We describe an emerging entity, recently recognized as a pitfall in the diagnostic practice among eosinophilic renal cell tumours. METHODS: A 60-year-old male underwent enucleation of a 1.2 cm nodule. Immunohistochemistry and FISH analysis were performed. RESULTS: Histology revealed a neoplasm composed of large cells with eosinophilic cytoplasm, Fuhrman grade 3, arranged in papillae. At the immunohistochemical level, cells showed positivity for AMACR and CD10. Fluorescence in situ hybridization (FISH) demonstrated gains of chromosomes 7 and 17 and loss of Y. A diagnosis of oncocytic papillary renal cell carcinoma was made. CONCLUSIONS: The distinction between renal oncocytoma and oncocytic papillary renal cell carcinoma is of substantial importance because of their different behaviour and prognosis, since the latter has malignant potential. Although the available evidence supporting tumour enucleation as the surgical treatment for renal cortical tumours < or = 4 cm, due to aforementioned clinicopathological features such tumours need to be evaluated using appropriate immunophenotypical and cytogenetic analyses.


Assuntos
Adenoma Oxífilo/diagnóstico , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Rim/patologia , Carcinoma de Células Renais/classificação , Diagnóstico Diferencial , Humanos , Neoplasias Renais/classificação , Masculino , Pessoa de Meia-Idade
7.
Nanotechnology ; 23(21): 215206, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22551529

RESUMO

We report on the KrF-laser ablation synthesis, purification and photocurrent generation properties of single-wall carbon nanotubes (SWCNTs). The thermally purified SWCNTs are integrated into hybrid photovoltaic (PV) devices by spin-coating them onto n-Si substrates. These novel SWCNTs/n-Si hybrid devices are shown to generate significant photocurrent (PC) over the entire 250-1050 nm light spectrum with external quantum efficiencies (EQE) reaching up to ~23%. Our SWCNTs/n-Si hybrid devices are not only photoactive in the traditional spectral range of Si solar cells, but generate also significant PC in the UV domain (below 400 nm). This wider spectral response is believed to be the result of PC generation from both the SWCNTs themselves and the tremendous number of local p-n junctions created at the nanotubes/Si interface. To assess the prevalence of these two contributions, the EQE spectra and J-V characteristics of these hybrid devices were investigated in both planar and top-down configurations, as a function of SWCNTs' film thickness. A sizable increase in EQE in the near UV with respect to the silicon is observed in both configurations, with a more pronounced UV photoresponse in the planar mode, confirming thereby the role of SWCNTs in the photogeneration process. The PC generation is found to reach its maximum for an optimal the SWCNT film thickness, which is shown to correspond to the best trade-off between lowest electrical resistance and highest optical transparency. Finally, by analyzing the J-V characteristics of our SWCNTs/n-Si devices with an equivalent circuit model, we were able to point out the contribution of the various electrical components involved in the photogeneration process. The SWCNTs-based devices demonstrated here open up the prospect for their use in highly effective photovoltaics and/or UV-light sensors.


Assuntos
Fontes de Energia Elétrica , Lasers , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Silício/química , Desenho de Equipamento , Análise de Falha de Equipamento , Nanotubos de Carbono/efeitos da radiação , Tamanho da Partícula , Silício/efeitos da radiação , Raios Ultravioleta
8.
J Nanosci Nanotechnol ; 11(10): 9202-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22400324

RESUMO

We report on the multiwall carbon nanotube application as energy conversion material to fabricate thin film solar cells, with nanotubes acting as photogeneration sites as well as charge separators, collectors and carrier transporters. The device consists of a semitransparent thin film of nanotubes coating a n-type crystalline silicon substrate. Under illumination electron-hole (e-h) pairs, generated in the nanotubes and in the silicon substrate underneath, are split and charges are transported through the nanotubes (electrons) and the n-Si (holes). We found that a suitable thickness of the nanotube thin film, high density of Schottky junctions between nanotubes and n-Si and lowest number of nanotube walls are all fundamental parameters to improve the device incident photon to electron conversion efficiency. Multiwall carbon nanotubes have been synthesized by chemical vapour deposition in an ultra high vacuum chamber by evaporating a given amount of iron at room temperature and then exposing the substrate kept at 800 degrees C at acetylene gas. The amount of deposited iron is found to directly affect the nanotube size distribution (inner and outer diameter) and therefore the number of walls of the nanotubes.

9.
J Nanosci Nanotechnol ; 11(10): 9321-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22400344

RESUMO

In this paper we illustrate a simple method for the production of multiwall carbon nanotubes thin films decorated with copper metal nanoparticles. The structural information obtained from the transmission electron microscopy study performed on samples differing in the quantity of deposited Copper was linked to the opto-electronic properties evaluated with photo-electrochemical measurements. The photo-response evaluated in terms of incident photon-to-charge carrier generation efficiency varied for different sized-Cu-multiwall carbon nanotubes samples across all the visible and near-ultraviolet photon energy range with respect to the response of bare carbon tubes. The photo-response from the sample covered with of 0.5 nm Cu nominal thickness, reached 10.2%, a value 2 times higher than that measured for bare carbon tubes of 5.9%. While this value decreased to 2.8% when the Cu nominal coverage thickened up to 3 nm. The increase in the photo-response found was interpreted as being the result of a remarkable charge transfer between the Cu metal nanoparticles and the carbon atoms in the tube due to the formation of a strong ionic bond at their interface. The results obtained prove that the metal nanoparticle-carbon nanotube composites have optical, electrical and structural properties that can be applied in a variety of nanoscale architectures for novel photo-electrochemical devices.

10.
Nanotechnology ; 22(3): 035701, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21149958

RESUMO

We show that Cu metal nanoparticle-multiwall carbon nanotube (MWCNT) assemblies can act as a new hybrid photoactive layer in photo-electrochemical devices. The carbon nanotube (CNT) composites were formed by a controlled thermal deposition of copper which produced crystalline metal nanoparticles localized on the carbon tube outer walls. The photoresponse evaluated in terms of IPCE (incident photon-to-charge carrier generation efficiency) varied for different sized-Cu-MWCNT samples across all the visible and near ultraviolet photon energy range with respect to the response of bare MWCNTs. In the case of 0.2 nm Cu nominal thickness, the IPCE increased, reaching 15%, a value 2.5 times higher than that measured for bare MWCNTs. As the Cu nominal coverage thickened, the IPCE started to decrease and become totally ineffective after 1 nm deposited Cu. The IPCE increase found was interpreted as being the result of a remarkable charge transfer between the Cu metal nanoparticles and the CNTs due to the formation of a strong ionic bond at their interface. The results obtained prove that the metal nanoparticle-CNT composites have optical, electrical and structural properties that can be applied in a variety of nanoscale architectures for novel photo-electrochemical devices.

11.
Mod Pathol ; 22(8): 1016-22, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19396149

RESUMO

The microphthalmia transcription factor/transcription factor E (TFE)-family translocation renal cell carcinomas bear specific translocations that result in overexpression of TFE3 or TFEB. TFE3 fusion gene product overexpression occurs as consequence of different translocations involving chromosome Xp11.2, whereas TFEB overexpression is the result of the specific translocation t(6;11)(p21;q12), which fuses the Alpha gene to TFEB. Both TFE3 and TFEB are closely related members of the microphthalmia transcription factor/TFE-family, which also includes TFEC and microphthalmia transcription factor. These transcription factors have overlapping transcriptional targets. Overexpression of microphthalmia transcription factor has been shown to mediate the expression of cathepsin-K in osteoclasts. We hypothesize that the overexpression of the related TFE3 fusion proteins and TFEB in translocation renal cell carcinomas may have the same effect. We studied cathepsin-K in 17 cytogenetically confirmed microphthalmia transcription factor/TFE-family translocation renal cell carcinomas. Seven cases showed a t(6;11)(p21;q12), ten cases showed translocations involving Xp11.2; five cases t(X;1)(p11;q21) resulting in a PRCC-TFE3 gene fusion; three cases t(X;1)(p11;p34) resulting in a PSF-TFE3 gene fusion, one t(X;17)(p11;q25) resulting in an ASPL-TFE3 gene fusion, and one t(X;3)(p11;q23) with an unknown TFE3 gene fusion. As control we analyzed cathepsin-K in 210 clear cell, 40 papillary, 25 chromophobe renal cell carcinomas and 30 oncocytomas. All seven TFEB translocation renal cell carcinomas were labeled for cathepsin-K. Among the cytogenetically confirmed TFE3 translocation renal cell carcinomas, 6 out of 10 were positive. None of the other renal neoplasms expressed cathepsin-K. We conclude the following: (1) cathepsin-K is consistently and strongly expressed in TFEB translocation renal cell carcinomas and in 6 of 10 TFE3 translocation renal cell carcinomas. (2) Cathepsin-K immunolabeling in both TFE3 and TFEB translocation renal cell carcinomas distinguishes these neoplasms from the more common adult renal cell carcinomas, and may be a specific marker of these neoplasms. (3) These results further support the concept that the overexpression of TFE3 or TFEB in these neoplasms activates the expression of genes normally regulated by microphthalmia transcription factor in other cell types.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Biomarcadores Tumorais/análise , Carcinoma de Células Renais/genética , Catepsinas/biossíntese , Neoplasias Renais/genética , Adolescente , Adulto , Idoso , Carcinoma de Células Renais/metabolismo , Catepsina K , Criança , Pré-Escolar , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Neoplasias Renais/metabolismo , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Análise Serial de Tecidos , Translocação Genética , Adulto Jovem
12.
Pancreatology ; 9(1-2): 25-33, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19077452

RESUMO

PURPOSE: Although ductal adenocarcinoma is the most common and well known pancreatic tumor type, other distinct epithelial neoplasms affecting the pancreas that show different symptoms, biological behaviors and outcomes are becoming more frequently recognized and documented. Pancreatic epithelial tumors may be separated into ductal and nonductal neoplasms. The former group includes pancreatic ductal adenocarcinoma, intraductal papillary-mucinous tumor, mucinous cystic tumor and serous cystic tumor. The latter group includes pancreatic endocrine tumor, pancreatic acinar cell carcinoma, pancreatoblastoma and solid-pseudopapillary tumor. The aim of this review is to summarize recently acquired knowledge regarding the molecular characterization of these uncommon pancreatic epithelial neoplasms. RECENT FINDINGS: Molecular studies of uncommon pancreatic epithelial tumors suggest that the different morphological entities are associated with distinct molecular profiles, highlighting the involvement of different molecular pathways leading to the development of each subtype of pancreatic neoplasm. CONCLUSION: The correct classification of rare pancreatic epithelial tumors and the identification of their characteristic molecular aspects is the fundamental starting point in identifying novel diagnostic molecular tools and new targets for innovative therapeutic strategies.


Assuntos
Neoplasias Pancreáticas/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/patologia , Carcinoma de Células Acinares/genética , Carcinoma de Células Acinares/patologia , Cistadenoma Mucinoso/genética , Cistadenoma Mucinoso/patologia , Humanos , Neoplasias Pancreáticas/patologia
13.
Pathologica ; 100(6): 454-60, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19475886

RESUMO

Renal cell neoplasms are a heterogeneous group of tumours in terms of pathological features and prognostic behaviour. The genetics of these tumours may aid in correct diagnosis and accurate assessment of prognosis. In ambiguous cases it may be necessary to utilise new markers that are capable of further discerning renal cell neoplasms. Fluorescence in situ hybridization (FISH) on formalin-fixed, paraffin-embedded tissue is an increasingly useful technique in the detection of many diagnostic chromosomal abnormalities, among which chromosomes 1, 2, 3p, 6, 7, 10, 17 and Y are the most common. The addition of FISH to histological evaluation improves the diagnostic accuracy of core biopsies from renal masses, which may have an important impact in clinical management of many cases due to newer therapeutic approaches, including cryo- or radiofrequency ablation, nephron-sparing surgeries and target therapies.


Assuntos
Carcinoma de Células Renais/patologia , Hibridização in Situ Fluorescente , Neoplasias Renais/patologia , Adenocarcinoma Mucinoso/diagnóstico , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/patologia , Adenoma/diagnóstico , Adenoma/genética , Adenoma/patologia , Adenoma Oxífilo/diagnóstico , Adenoma Oxífilo/genética , Adenoma Oxífilo/patologia , Adulto , Aneuploidia , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/genética , Criança , Aberrações Cromossômicas , Cromossomos Humanos/ultraestrutura , Cromossomos Humanos X/ultraestrutura , Humanos , Falência Renal Crônica/complicações , Neoplasias Renais/diagnóstico , Neoplasias Renais/genética , Translocação Genética
14.
J Perinatol ; 27(4): 247-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17377608

RESUMO

We report a 27-week, 850 g infant with severe Streptococcus group B sepsis and life-threatening hyperkalemia due to progressive anuria. On the fourth day of life, after he failed treatment with diuretics, salbutamol, insulin, calcium gluconate and sodium bicarbonate, he was treated with sorbitol-free Kayexalate enemas. Potassium level slowly decreased from 9.2 mmol/l to normal level along with a recovery of normal urine output. On the 11th day of life, clinical and radiological signs of a perforated necrotizing enterocolitis (NEC) occurred and the patient required surgical intestinal resection. Histologic examination of the ileum specimen revealed areas of necrosis with fibrosis and giant cell reaction to a nonpolarizable material consistent with sodium polystyrene sulfonate. Usually, Kayexalate is suspended in hyperosmolar sorbitol solutions and the elevated osmolarity seems to be responsible for hemorrhagic colitis, transmural necrosis and definitely NEC. Our case report shows that Kayexalate per se, and not necessarily suspended in sorbitol, can lead to gastrointestinal tract complications and NEC in preterm infants.


Assuntos
Resinas de Troca de Cátion/efeitos adversos , Enterocolite Necrosante/etiologia , Hiperpotassemia/tratamento farmacológico , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Poliestirenos/efeitos adversos , Enterocolite Necrosante/patologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Sepse/patologia , Infecções Estreptocócicas/complicações , Streptococcus agalactiae
16.
Eur. j. anat ; 8(2): 95-99, sept. 2004. ilus
Artigo em Inglês | IBECS | ID: ibc-137847

RESUMO

Leptin is a peptide hormone encoded by the obgene and released by adipocytes. Over the past few years, the synthesis, regulation and effects of leptin have been extensively investigated in view of its pleiotropic role in human (patho)physiology. This work aimed at reviewing current morphological knowledge on leptin synthesis and secretion in adipocytes. It is concluded that the intracellular trafficking of leptin and the structural basis of leptin secretion remain to be defined. Further morphological work, especially at the ultrastructural level, is needed to firmly establish the intracellular distribution and the release pathways of the hormone (AU)


No disponible


Assuntos
Feminino , Humanos , Masculino , Leptina/análogos & derivados , Leptina/administração & dosagem , Tecido Adiposo/anormalidades , Tecido Adiposo , Forma do Núcleo Celular/genética , Hormônios Peptídicos/administração & dosagem , Hormônios Peptídicos , Secreções Corporais/citologia , Leptina , Leptina/metabolismo , Tecido Adiposo/lesões , Tecido Adiposo/metabolismo , Forma do Núcleo Celular/fisiologia , Hormônios Peptídicos/classificação , Hormônios Peptídicos/farmacologia , Secreções Corporais
17.
IUBMB Life ; 51(2): 111-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11463162

RESUMO

The influence of the medium composition on the dynamic properties of mitochondrial membranes on depolarization was studied by following the fluorescence anisotropy changes of mitochondria-bound 1,6-diphenyl-1,3,5-hexatriene (DPH) and hematoporphyrin (HP) as reporters, respectively, of lipid and protein regions. On collapse of the potential, the membrane fluidity increased in NaCl-, KCl-, and monosaccharide-based media and decreased in disaccharides. Infrared spectroscopy experiments suggested that disaccharides likely change water's structure and association on the membrane surface. These results indicate that disaccharides induce membrane perturbation, which may interfere in the study of structure-function correlation in biological membranes.


Assuntos
Dissacarídeos/farmacologia , Membranas Intracelulares/efeitos dos fármacos , Fluidez de Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Animais , Membranas Intracelulares/fisiologia , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Photochem Photobiol B ; 57(2-3): 94-101, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11154089

RESUMO

Photodynamic therapy (PDT) appears to be a novel promising modality to prevent intimal hyperplasia (IH) and restenosis after angioplasty. Local PDT, that consists of local delivery of photosensitizing agents followed by intraluminal local irradiation, represents a recent advancement. This methodology requires optimization in order to achieve the best prompt outcome especially in terms of pharmacokinetics of the photosensitizing agent. We studied the pharmacokinetic properties by using the photosensitizing agent Zn(II)-phthalocyanine (ZnPc), locally released by a channeled balloon. The efficacy of local PDT in reducing IH was evaluated in an experimental rabbit model of arterial injury. The maximum accumulation of ZnPc was found at 30 min: the injured portion of the artery gave a ZnPc recovery of 1.18 micromol/mg, as compared with undetectable amounts of ZnPc in the non injured arteries; within 90 min after the local delivery, clearance of the agent was almost complete. Local PDT produced an effective reduction of IH in our vascular injury model: at 7, 14, 21 and 28 days IH and intima/media ratio (IMR) was significantly reduced as compared with balloon injured arteries. The local delivery of ZnPc showed favourable pharmacokinetic properties, that allow the performance of PDT immediately after the vascular injury. Local PDT performed in these conditions represents a promising approach to prevent IH after balloon injury. Further studies are needed to better clarify the biological response of the injured arterial wall to local PDT.


Assuntos
Artéria Femoral/lesões , Artéria Ilíaca/lesões , Indóis/uso terapêutico , Compostos Organometálicos/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Modelos Animais de Doenças , Artéria Femoral/patologia , Hiperplasia/tratamento farmacológico , Artéria Ilíaca/patologia , Indóis/farmacocinética , Masculino , Compostos Organometálicos/farmacocinética , Fármacos Fotossensibilizantes/farmacocinética , Coelhos
19.
Biochemistry ; 38(29): 9295-300, 1999 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-10413503

RESUMO

The dynamic properties of protein and lipid regions of mitochondrial membranes during the permeability transition (PT) process were studied by following the anisotropy changes of hematoporphyrin (HP) and 1,6-diphenyl-1,3,5-hexatriene (DPH), respectively. We show that opening of the PT pore is accompanied by a remarkable increase of mitochondrial membrane fluidity which is specifically localized to protein sites, while lipid domains are unaffected. The increased membrane fluidity is not related to the collapse of transmembrane potential that follows the PT, as demonstrated by a comparison between the anisotropy properties of permeabilized mitochondria and impermeable, depolarized organelles. Parameters such as osmotic swelling and temperature, which are shown to affect the mitochondrial membrane dynamics in the absence of permeability transition, cannot alone account for the pore dynamical properties. We suggest that the observed increase in fluidity is mainly due to a conformational change of pore-forming protein(s) during the "assembly" of the PT pore.


Assuntos
Membranas Intracelulares/química , Membranas Intracelulares/metabolismo , Fluidez de Membrana , Mitocôndrias Hepáticas/química , Mitocôndrias Hepáticas/metabolismo , Animais , Difenilexatrieno/análogos & derivados , Difenilexatrieno/metabolismo , Polarização de Fluorescência , Hematoporfirinas/metabolismo , Membranas Intracelulares/fisiologia , Fluidez de Membrana/fisiologia , Potenciais da Membrana , Mitocôndrias Hepáticas/fisiologia , Dilatação Mitocondrial/fisiologia , Permeabilidade , Ratos , Ratos Wistar , Termodinâmica
20.
Biochem J ; 338 ( Pt 1): 221-7, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9931319

RESUMO

We have studied the distribution properties of haematoporphyrin (HP) and protoporphyrin (PP) in mitochondria and endoplasmic reticulum after isolation from rat liver. The photosensitizing efficiency of porphyrin on the Ca2+ influx function of microsomes has been compared with that obtained on Ca2+ uptake in mitochondria. HP and PP are accumulated in microsomes to a greater extent than in mitochondria, both porphyrins binding to membrane protein sites. The Ca2+ influx functions of mitochondria and microsomes, before and after irradiation in the presence of HP or PP, were studied by following the changes in the free Ca2+ concentration in the medium as revealed by the variations in fluorescence intensity of the Ca2+ indicator Calcium Green-1. For the same amount of incorporated porphyrin, the Ca2+ influx function of microsomes is degraded by irradiation more rapidly than that of mitochondria. The protective effect of dithiothreitol suggests that thiol groups in the Ca2+-transporting enzyme are the preferential targets of the photodynamic effect. These results suggest that intracellular Ca2+ movements are altered primarily by the endoplasmic reticulum rather than by mitochondrial damage, in good agreement with other observations made in porphyrin-loaded irradiated cells.


Assuntos
Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Hematoporfirinas/farmacologia , Mitocôndrias Hepáticas/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/efeitos da radiação , Cálcio/efeitos da radiação , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/efeitos da radiação , Hematoporfirinas/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Microssomos Hepáticos/efeitos da radiação , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos da radiação , Protoporfirinas/metabolismo , Ratos , Ratos Wistar
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