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1.
Front Cardiovasc Med ; 10: 1287907, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075968

RESUMO

We presented the case of a patient with non-ST-elevation myocardial infarction with coronary arteries of an anomalous origin, an interarterial course of the LMCA, a unique wide-angle "right" main bifurcation lesion, and a high SYNTAX score. Management with contemporary PCI and imaging may be an alternative to surgery.

2.
Semin Dial ; 36(5): 374-381, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36263693

RESUMO

OBJECTIVE: Endovascular intervention for thrombosed aneurysmal arteriovenous fistula (AVF) is still a challenge. Manual compression technique (MCT)-assisted angioplasty may be helpful, but there is no evidence or data to support it. METHODS: From January 2018 to May 2021, patients with thrombosed aneurysmal AVFs were retrospectively enrolled. The patients were separated into the MCT group or the traditional group according to the procedure received. Technical failure, clinical failure, 90-day patency, and safety were analyzed. RESULTS: A total of 159 cases (64 ± 12 years old, 60% male) were enrolled, of which 87 cases received MCT and 72 underwent traditional angioplasty. No technical failure was observed in the MCT group, while five technical failures were observed in the traditional group (0% vs. 7%, p = 0.02). There were no differences in the clinical failure rate (3% vs. 7%, p = 0.30), 90-day patency rate, or procedure time between the MCT group and the traditional group. There was no symptomatic pulmonary embolism or other complication in the two groups. CONCLUSION: MCT is a low-cost, less invasive, and safe procedure for thrombosed aneurysmal AVF, and it achieves a higher technical success rate than traditional angioplasty.

3.
J Vasc Surg Cases Innov Tech ; 6(3): 479-482, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32944675

RESUMO

Heterotopic ossification (HO) in patients with spinal cord injury could lead to local tissue swelling and sometimes mimic the clinical presentation of deep vein thrombosis. Recognition and effective management is critical. We report the case of a bedridden patient with spinal cord injury presenting with diffuse right lower limb swelling caused by external venous compression from HO. The patient underwent surgery and local radiation therapy. Postoperative venography disclosed a marked improvement in the blood flow, and symptoms were alleviated. We discuss the role of venography in the diagnosis and treatment of venous compression in the setting of HO.

4.
Medicine (Baltimore) ; 98(30): e16574, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31348289

RESUMO

RATIONALE: Sodium polystyrene sulfonate is commonly administered to treat hyperkalemia. Severe pneumonia due to aspiration of this drug is rare and no survival case has thus far been reported. PATIENT CONCERNS: A 45-year-old man was hospitalized for acute decompensated heart failure and acute kidney injury with hyperkalemia. He aspirated sodium polystyrene sulfonate while consuming the drug. Severe acute respiratory distress syndrome (ARDS) developed rapidly, and he was transferred to the intensive care unit (ICU). DIAGNOSES: Chest radiography results after aspiration showed new consolidation in the left upper lung. He underwent emergency bronchoscopy, which revealed a considerable amount of yellow mud-like material in the trachea and bronchi. Chest radiography results after the bronchoscopic removal of the foreign material revealed rapid resolution of the left upper lung consolidation. INTERVENTIONS: In the ICU, mechanical ventilation with low tidal volume and high positive end-expiratory pressure was administered and extracorporeal membrane oxygenation (ECMO) was set up for treating severe ARDS. We arranged an emergency bronchoscopy for diagnosis and removal of polystyrene sulfonate. OUTCOMES: ECMO was discontinued after 10 days and the patient was discharged after approximately 2 weeks. LESSONS: Aspiration of sodium polystyrene sulfonate is not common but can be lethal. Clinicians should be cautious and appropriately inform patients of the aspiration risk while administering this drug. Mechanical ventilation and bronchoscopy were effective treatments for severe ARDS caused by aspiration of this drug.


Assuntos
Poliestirenos/efeitos adversos , Aspiração Respiratória/complicações , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/terapia , Broncoscopia/métodos , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Respiração Artificial/métodos , Índice de Gravidade de Doença
5.
Biochimie ; 94(11): 2376-81, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22732192

RESUMO

The Cys703 to Ile or His mutation within Saccharomyces cerevisiae oxidosqualene-lanosterol cyclase ERG7 (ERG7(C703I/H)) generates an unusual truncated bicyclic rearranged intermediate, (8R,9R,10R)-polypoda-5,13E,17E,21-tetraen-3ß-ol, related to iridal-skeleton triterpenoid. Numerous oxidosqualene-cyclized truncated intermediates, including tricyclic, unrearranged tetracyclic with 17α/ß exocyclic hydrocarbon side chain, rearranged tetracyclic, and chair-chair-chair tricyclic intermediates (compounds 3-9), were also isolated from the ERG7(C703X) site-saturated mutations or the ERG7(F699T/C703I) double mutation, indicating the functional role of the Cys703 residue in stabilizing the bicyclic C-8 cation and the rearranged intermediate or interacting with Phe699, and opened a new avenue of engineering ERG7 for producing biological active agents.


Assuntos
Substituição de Aminoácidos , Transferases Intramoleculares/química , Transferases Intramoleculares/metabolismo , Mutação , Saccharomyces cerevisiae/enzimologia , Triterpenos/metabolismo , Sequência de Aminoácidos , Biocatálise , Cisteína , Histidina , Transferases Intramoleculares/genética , Isoleucina , Modelos Moleculares , Conformação Proteica , Saccharomyces cerevisiae/metabolismo
6.
Acta Biomater ; 8(8): 2996-3004, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22561668

RESUMO

New magnetic-based core-shell particles (MBCSPs) were developed to target skin cancer cells while delivering chemotherapeutic drugs in a controlled fashion. MBCSPs consist of a thermo-responsive shell of poly(N-isopropylacrylamide-acrylamide-allylamine) and a core of poly(lactic-co-glycolic acid) (PLGA) embedded with magnetite nanoparticles. To target melanoma cancer cells, MBCSPs were conjugated with Gly-Arg-Gly-Asp-Ser (GRGDS) peptides that specifically bind to the α(5)ß(3) receptors of melanoma cells. MBCSPs consist of unique multifunctional and controlled drug delivery characteristics. Specially, they can provide dual drug release mechanisms (a sustained release of drugs through degradation of PLGA core and a controlled release in response to changes in temperature via thermo-responsive polymer shell), and dual targeting mechanisms (magnetic localization and receptor-mediated targeting). Results from in vitro studies indicate that GRGDS-conjugated MBCSPs have an average diameter of 296 nm and exhibit no cytotoxicity towards human dermal fibroblasts up to 500 µg ml(-1). Further, a sustained release of curcumin from the core and a temperature-dependent release of doxorubicin from the shell of MBCSPs were observed. The particles also produced a dark contrast signal in magnetic resonance imaging. Finally, the particles were accumulated at the tumor site in a B16F10 melanoma orthotopic mouse model, especially in the presence of a magnet. Results indicate great potential of MBCSPs as a platform technology to target, treat and monitor melanoma for targeted drug delivery to reduce side effects of chemotherapeutic reagents.


Assuntos
Resinas Acrílicas/química , Sistemas de Liberação de Medicamentos/métodos , Ácido Láctico/química , Melanoma/tratamento farmacológico , Nanopartículas/química , Ácido Poliglicólico/química , Neoplasias Cutâneas/tratamento farmacológico , Animais , Morte Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Hidrodinâmica , Imageamento por Ressonância Magnética , Magnetismo , Melanoma/patologia , Camundongos , Nanopartículas/toxicidade , Tamanho da Partícula , Imagens de Fantasmas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Neoplasias Cutâneas/patologia , Propriedades de Superfície/efeitos dos fármacos
7.
Biomaterials ; 33(3): 876-85, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22019117

RESUMO

Inflammatory responses and associated products have been implicated in cancer metastasis. However, the relationship between these two processes is uncertain due to the lack of a suitable model. Taking advantage of localized and controllable inflammatory responses induced by biomaterial implantation and the capability of tissue scaffolds to release a wide variety of chemokines, we report a novel system for studying the molecular mechanisms of inflammation-mediated cancer metastasis. The animal model is comprised of an initial subcutaneous implantation of biomaterial microspheres which prompt localized inflammatory responses, followed by the transplantation of metastatic cancer cells into the peritoneal cavity or blood circulation. Histological results demonstrated that substantial numbers of B16F10 cells were recruited to the site nearby biomaterial implants. There was a strong correlation between the degree of biomaterial-mediated inflammatory responses and number of recruited cancer cells. Inflammation-mediated cancer cell migration was inhibited by small molecule inhibitors of CXCR4 but not by neutralizing antibody against CCL21. Using chemokine-releasing scaffolds, further studies were carried out to explore the possibility of enhancing cancer cell recruitment. Interestingly, erythropoietin (EPO) releasing scaffolds, but not stromal cell-derived factor-1α-releasing scaffolds, were found to accumulate substantially more melanoma cells than controls. Rather unexpectedly, perhaps by indirectly reducing circulating cancer cells, mice implanted with EPO-releasing scaffolds had ~30% longer life span than other groups. These results suggest that chemokine-releasing scaffolds may potentially function as implantable cancer traps and serve as powerful tools for studying cancer distraction and even selective annihilation of circulating metastatic cancer cells.


Assuntos
Quimiocinas/química , Melanoma/metabolismo , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Reação a Corpo Estranho/imunologia , Humanos , Melanoma/imunologia , Melanoma/patologia , Camundongos , Metástase Neoplásica/imunologia , Metástase Neoplásica/fisiopatologia
8.
Biomaterials ; 31(14): 3997-4008, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20185171

RESUMO

Despite significant advances in the understanding of tissue responses to biomaterials, most implants are still plagued by inflammatory responses which can lead to fibrotic encapsulation. This is of dire consequence in tissue engineering, where seeded cells and bioactive components are separated from the native tissue, limiting the regenerative potential of the design. Additionally, these interactions prevent desired tissue integration and angiogenesis, preventing functionality of the design. Recent evidence supports that mesenchymal stem cells (MSC) and hematopoietic stem cells (HSC) can have beneficial effects which alter the inflammatory responses and improve healing. The purpose of this study was to examine whether stem cells could be targeted to the site of biomaterial implantation and whether increasing local stem cell responses could improve the tissue response to PLGA scaffold implants. Through incorporation of SDF-1alpha through factor adsorption and mini-osmotic pump delivery, the host-derived stem cell response can be improved resulting in 3X increase in stem cell populations at the interface for up to 2 weeks. These interactions were found to significantly alter the acute mast cell responses, reducing the number of mast cells and degranulated mast cells near the scaffold implants. This led to subsequent downstream reduction in the inflammatory cell responses, and through altered mast cell activation and stem cell participation, increased angiogenesis and decreased fibrotic responses to the scaffold implants. These results support that enhanced recruitment of autologous stem cells can improve the tissue responses to biomaterial implants through modifying/bypassing inflammatory cell responses and jumpstarting stem cell participation in healing at the implant interface.


Assuntos
Movimento Celular/efeitos dos fármacos , Quimiocina CXCL12/farmacologia , Inflamação/patologia , Ácido Láctico/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Ácido Poliglicólico/farmacologia , Alicerces Teciduais/química , Animais , Citocinas/metabolismo , Reação a Corpo Estranho/patologia , Mobilização de Células-Tronco Hematopoéticas , Implantes Experimentais , Transplante de Células-Tronco Mesenquimais , Camundongos , Camundongos Endogâmicos BALB C , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
9.
Arch Biochem Biophys ; 421(1): 42-53, 2004 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-14678783

RESUMO

The oxidosqualene-lanosterol cyclase (OSC) from bovine liver has been isolated from the microsomal membrane fraction and purified to homogeneity by ultracentrifugation, Q-Sepharose, hydroxyapatite, and HiTrap heparin chromatographies. The purified protein required Triton X-100 to retain its highest activity. The cyclase had a molecular mass of approximately 70 and approximately 140 kDa, as evidenced by a single protein band on silver-stained SDS-PAGE and Coomassie-stained PAGE, respectively. Results from Edman degradation of OSC suggested that it might have a blocked N-terminus. Further peptide mapping coupled with tandem mass spectrometric determination identified three peptide fragments, ILGVGPDDPDLVR, LSAEEGPLVQSLR, and NPDGGFATYETK, which are highly homologous to human, rat, and mouse OSCs. The purified cyclase showed pH and temperature optima at pH 7.4 and 37 degrees C, respectively. The apparent K(M) and k(cat)/K(M) values were estimated to be 11 microM and 1.45 mM(-1)min(-1), respectively. Inhibition studies using both Ro48-8071 and N-(4-methylenebenzophenonyl)pyridinium bromide showed potent inhibition of OSC with an IC(50) of 11 nM and 0.79 microM, respectively. Results from DTNB modification and DTNB coupled with Ro48-8071 competition study suggest that two sulfhydryl groups are involved in the catalysis but not located in the substrate binding pocket or catalytic active site. The purified OSC was maximally inactivated by diethyl pyrocarbonate near neutral pH and re-activated by hydroxylamine, indicating the modification of histidine residues. The stoichiometry of histidine modification and the extent of inactivation showed that two essential histidine residues per active site are necessary for complete bovine liver OSC activity.


Assuntos
Transferases Intramoleculares/antagonistas & inibidores , Transferases Intramoleculares/isolamento & purificação , Microssomos Hepáticos/enzimologia , Sequência de Aminoácidos , Animais , Benzofenonas/química , Benzofenonas/farmacologia , Bovinos , Cisteína/química , Cisteína/metabolismo , Dietil Pirocarbonato/farmacologia , Ácido Ditionitrobenzoico/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Histidina/química , Histidina/metabolismo , Concentração de Íons de Hidrogênio , Hidroxilamina/farmacologia , Concentração Inibidora 50 , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Cinética , Espectrometria de Massas/métodos , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Análise de Sequência de Proteína/métodos , Homologia de Sequência de Aminoácidos
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