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1.
Bioorg Chem ; 115: 105180, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34332234

RESUMEN

Marine microbes secrete exopolymeric substances (EPS), which surrounds the biofilm and inhibits the fungal growth. Elucidation of the structure and function of the extracellular exopolymeric substances is of vital relevance therapeutically. The active compound responsible for bioactivity was purified and characterized using TLC, LC/MS/MS, GC/MS and FT-IR. Bioactivity of the characterized cyclic peptides (CLPs) against azole resistant and susceptible Candida strains were examined for growth and biofilm formation using scanning electron microscopy, flow cytometry, confocal microscopy. In the present study we identified bioactive cyclic peptides from marine isolated Neobacillus drentensis that exhibited promising tensio-active properties and antifungal efficacy against azole resistant and susceptible Candida albicans. The cluster is composed of five CLP isoforms which were sequenced and identified as new peptides with compositional and structural variations in the amino acid sequence and fatty acid chain. In vitro cytotoxic activity of CLPs was tested in human fibroblast normal cells. We have observed that the CLPs repressed the Candida albicans growth and multiplication by inhibiting the biofilm formation and disruption of branching filamentous hyphae. CLPs have been found to arrest the C. albicans cell cycle by a block at G1-S transition followed by apoptotic cell death. The current studies suggest these natural marine derived CLPs function as potential anti-biofilm agents against azole C. albicans resistant strains.


Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Bacillus/química , Candida albicans/efectos de los fármacos , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Biopelículas/efectos de los fármacos , Candida albicans/fisiología , Candidiasis/tratamiento farmacológico , Línea Celular , Humanos
2.
J Thromb Thrombolysis ; 50(3): 484-498, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32601850

RESUMEN

The relation of device related thrombosis (DRT) and major bleeding after left atrial appendage closure (LAAC) to laboratory thrombosis and hemostasis markers has not been studied. We performed a prospective case control study to identify clinical characteristics and laboratory markers in patients who developed DRT and major bleeding following WATCHMAN LAAC. Thromboelastography, platelet aggregation (PA), urinary 11-dehydrothromboxane B2 (UTX), fibrinogen, D-dimer, thrombin time and von Willebrand factor activity were determined at baseline, immediately following, and at 45 and 180 days post-LAAC (n = 32) and outcomes were followed for 1 year. Baseline characteristics and thrombogenic profiles of patients with and without DRT and/or BARC bleeding were compared. Mean age was 76 ± 8 years and CHADS2 VASc score was 4.4 ± 1.4. There were 3 DRTs (2 within 6 months, and 1 at 12 months), 4 Type 3A BARC bleeds, and 2 non-cardiac deaths. Patients with DRT had higher baseline thrombin-induced platelet-fibrin clot strength (68.0 ± 1.8 vs. 62.7 ± 4.7 mm, p = 0.06); FCS (35.6 ± 6.0 vs. 24.4 ± 6.6 mm, p = 0.009); and D-dimer (1712 ± 2330 vs. 283 ± 213 ng/mL, p = 0.001). At baseline, 5 patients had all 3 factors associated with high thrombotic risk and 2 experienced a DRT within 6 months. Patients with Type 3A BARC bleeding had lower baseline collagen-induced and 45-day ADP-induced PA (p < 0.01 for both). DRT following LAAC was associated with a baseline prothrombogenic profile whereas bleeding was associated with low platelet reactivity. These preliminary findings warrant further validation and have future implications on patient selection and adjunctive antithrombotic therapy following LAAC.Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03040622 .


Asunto(s)
Fibrilación Atrial/cirugía , Corazón Auxiliar/efectos adversos , Trombosis/sangre , Trombosis/etiología , Anciano , Anciano de 80 o más Años , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Apéndice Atrial/cirugía , Coagulación Sanguínea , Estudios de Casos y Controles , Femenino , Hemorragia/inducido químicamente , Hemostasis , Humanos , Masculino , Estudios Prospectivos , Trombosis/prevención & control , Resultado del Tratamiento
3.
J Cardiovasc Electrophysiol ; 30(12): 2806-2810, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31661171

RESUMEN

INTRODUCTION: Cryoballoon ablation is commonly used to treat atrial fibrillation (AF). Femoral vein hemostasis after cryoballoon ablation for AF is routinely achieved with manual pressure (MP) after reversal of heparin and reassessment of the activated clotting time, or with a figure-of-eight suture (F8). The purpose of this randomized trial was to compare these two techniques for femoral vein hemostasis after cryoballoon ablation for AF in a patient population predominantly on novel anticoagulants (NOAC). METHODS AND RESULTS: Seventy consecutive patients who underwent cryoballoon ablation were randomized to either the MP or F8 for femoral vein hemostasis. Clinical and procedural characteristics were similar between the groups with the majority of patients treated with a NOAC. The total time in the electrophysiology laboratory for the MP group and the F8 group (197 ± 37 minutes vs 167 ± 36 minutes, respectively; P = .02), and the time from sheath removal until the patient left the laboratory (28 ± 9 minutes vs 20 ± 5 minutes, respectively; P < .0001) were significantly less in the F8 group. Additional pressure for hemostasis in the recovery suite was required more often in the MP Group, as opposed to the F8 group (29% vs 3%; P = .003). No major bleeding occurred and the rate of minor hematomas was statistically similar. CONCLUSIONS: Hemostasis obtained with a F8 suture after cryoballoon ablation for AF is associated with significantly less patient time in the electrophysiology laboratory, and an improved safety profile, compared with manual hemostasis, even amongst patients treated with a NOAC.


Asunto(s)
Fibrilación Atrial/cirugía , Cateterismo Periférico , Criocirugía , Vena Femoral/cirugía , Hemorragia/prevención & control , Hemostasis , Técnicas Hemostáticas , Técnicas de Sutura , Potenciales de Acción , Administración Oral , Anciano , Anticoagulantes/administración & dosificación , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Cateterismo Periférico/efectos adversos , Criocirugía/efectos adversos , Femenino , Vena Femoral/diagnóstico por imagen , Frecuencia Cardíaca , Hemorragia/sangre , Hemorragia/etiología , Técnicas Hemostáticas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Presión , Punciones , Factores de Riesgo , Técnicas de Sutura/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Virginia
4.
J Cardiovasc Electrophysiol ; 29(1): 17-21, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28877379

RESUMEN

INTRODUCTION: Left atrial appendage (LAA) closure with the WATCHMAN device, according to FDA labelling, is recommended in patients with a maximal LAA ostial width between 17 and 31 mm. The safety and efficacy of LAA closure in patients with a maximal LAA ostial width < 17 mm has not been evaluated. The goal of this study was to determine the acute and short-term safety and efficacy of LAA closure with the WATCHMAN device in patients with a maximal LAA ostial width < 17 mm. METHODS AND RESULTS: Thirty-two consecutive patients with a maximal LAA ostial width < 17 mm as determined by a screening transesophageal echocardiogram (TEE) underwent LAA closure with the WATCHMAN device between March 2015 and November 2016 at five medical centers, and were included in this study. Mean age, body mass index (BMI), and CHA2 DS2 -VASC score were 70.8 ± 8.6 years, 29.3 ± 6.5 kg/m2 , and 3.9 ±1.2, respectively. At the screening TEE, mean maximal LAA ostial width and depth were 15.6 ± 0.6 mm (range 14-16) and 23.2 ± 4.5 mm (range 13-31), respectively. Successful LAA closure with the WATCHMAN device was achieved in 31 of 32 patients (97%), with no major complications. TEE performed 45 days after LAA closure demonstrated no peridevice leak > 5 mm and no device related thrombi. Warfarin was discontinued in all 31 patients 45 days after LAA closure. CONCLUSIONS: LAA closure with the WATCHMAN device can be successfully and safely achieved in patients with a maximal LAA ostial width < 17 mm.


Asunto(s)
Apéndice Atrial/fisiopatología , Fibrilación Atrial/terapia , Cateterismo Cardíaco/instrumentación , Potenciales de Acción , Apéndice Atrial/diagnóstico por imagen , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/mortalidad , Fibrilación Atrial/fisiopatología , Función del Atrio Izquierdo , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/mortalidad , Bases de Datos Factuales , Ecocardiografía Doppler en Color , Ecocardiografía Transesofágica , Diseño de Equipo , Frecuencia Cardíaca , Humanos , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
5.
Catheter Cardiovasc Interv ; 92(1): 200-202, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29130638

RESUMEN

Atrial fibrillation (AF) is associated with an increased risk of stroke and thromboembolism (TE). The WATCHMANTM left atrial appendage (LAA) closure device is indicated to reduce the risk of TE from the LAA in patients with non-valvular AF. Here, we present a case of a patient with device-related thrombus who suffered a TE event two months after WATCHMANTM LAA closure and two weeks after switching from aspirin plus warfarin to aspirin plus clopidogrel therapy. Laboratory investigation identified the patient to be hypercoagulable and to be a non-responder to clopidogrel therapy. We discuss the potential role of platelet function testing to prevent device-related thrombi.


Asunto(s)
Fibrilación Atrial/terapia , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentación , Clopidogrel/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Tromboembolia/etiología , Anciano , Anticoagulantes/administración & dosificación , Aspirina/administración & dosificación , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/fisiopatología , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Resistencia a Medicamentos , Sustitución de Medicamentos , Ecocardiografía Transesofágica , Femenino , Humanos , Pruebas de Función Plaquetaria , Valor Predictivo de las Pruebas , Factores de Riesgo , Tromboembolia/sangre , Tromboembolia/diagnóstico por imagen , Factores de Tiempo , Resultado del Tratamiento , Warfarina/administración & dosificación
6.
Pacing Clin Electrophysiol ; 37(4): 481-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24215359

RESUMEN

BACKGROUND: Implantable defibrillator (ICD) therapy improves mortality in patients at risk for sudden cardiac death. Obese patients pose challenges during ICD implantation and may have an increased risk of procedure-related complications. The comparison of acute procedural success and safety of ICD implantation in obese and nonobese patients has not been previously reported. METHODS: A total of 181 patients underwent ICD implantation at a single institution. Obesity was defined as a body mass index (BMI) greater than or equal to 30 kg/m(2) . Acute safety and efficacy data were collected and analyzed from a prospectively maintained database, with retrospective chart review, as required. RESULTS: Among the 181 patients, 58 (32.0%) were obese. Mean BMI was 36.7 ± 6.3 kg/m(2) among obese patients and was 24.6 ± 3.1 kg/m(2) among nonobese patients (P < 0.001). Successful ICD implantation occurred in 58 of 58 (100%) obese patients and 122 of 123 (99.2%) nonobese patients (P = 1.0). A complication was observed in three of 58 (5.2%) obese patients and in seven of 123 (5.7%) nonobese patients (P = 1.0). Similarly, there was no difference in acute procedural success and safety in patients receiving a cardiac resynchronization therapy (CRT)-ICD. CONCLUSIONS: Acute success and safety of ICD implantation is similar in both obese and nonobese patients. This finding extended to patients treated with a CRT-ICD and among patients with extreme obesity. Obesity should probably not be a factor in determining whether a patient is a candidate for ICD implantation.


Asunto(s)
Desfibriladores Implantables/estadística & datos numéricos , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/prevención & control , Obesidad/epidemiología , Complicaciones Posoperatorias/mortalidad , Implantación de Prótesis/mortalidad , Anciano , Comorbilidad , District of Columbia/epidemiología , Femenino , Humanos , Incidencia , Masculino , Estudios Retrospectivos , Medición de Riesgo , Tasa de Supervivencia
7.
Eur J Ophthalmol ; 34(2): 471-479, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37671417

RESUMEN

PURPOSE: To determine if glaucoma medications are associated with pregnancy and/or postnatal complications. METHODS: Multicenter descriptive survey. Subjects were female patients 18-45 years who were previously pregnant with a diagnosis of glaucoma or ocular hypertension prior to pregnancy. Chart review queried diagnosis, glaucoma severity, and race. Survey questions were asked for each pregnancy and queried pregnancy age, medications used, and pregnancy outcomes/complications. RESULTS: 114 pregnancies of 56 patients (mean 2.0 pregnancies per patient) were included. Three pregnancies with therapeutic abortion were excluded from further analysis. Mean age during pregnancy was 29.1 ± 5.7 years. Of the 111 pregnancies, 20 (18.0%) used no medications and 91 (82.0%) used at least one medication. Medications were topical carbonic anhydrase inhibitors (n = 45), beta-blockers (n = 55), alpha-agonists (n = 56), and prostaglandin analogues (n = 28). Outcomes were: preterm contractions/labour (6.3%), miscarriage (4.5%), stillbirth (4.5%), induction of labour (11.9%), emergency/unplanned caesarean delivery (13.9%), neonatal intensive care unit (NICU) stay (15.8%), congenital anomalies (8.1%), and low birth weight (10.9%). Fisher exact test assessed outcome associations with individual agents, use of any agent, and different number of agents. Alpha-agonist use was associated with NICU stay: 25.5% rate (p = 0.012) in alpha-agonist use. Most of the alpha-agonist use NICU stays occurred in pregnancies with third trimester use. All other associations were not statistically significant. CONCLUSIONS: The data from this survey suggest an overall favourable safety profile for topical glaucoma medications in pregnancy, but further investigation is needed. Caution should be employed regarding third trimester alpha-agonist use owing to association with NICU stay.


Asunto(s)
Glaucoma , Hipertensión Ocular , Recién Nacido , Embarazo , Humanos , Femenino , Adulto Joven , Adulto , Masculino , Resultado del Embarazo , Glaucoma/tratamiento farmacológico , Cesárea , Antagonistas Adrenérgicos beta/uso terapéutico
8.
J Interv Card Electrophysiol ; 66(7): 1601-1607, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36604354

RESUMEN

BACKGROUND: With advancements in technology and ablation techniques, catheter ablation for the treatment of atrial fibrillation (AF) has become safer with time. In the past, standard-of-care recommended overnight stay for outpatient procedures. As safety has improved and procedure times have shortened, some centers have allowed for same-day discharge. We report the results of a multi-center, randomized clinical trial investigating the safety of same-day discharge post-cryoballoon ablation. METHODS: Patients with paroxysmal atrial fibrillation underwent pulmonary vein isolation (PVI) with the Medtronic Arctic Advance cryoballoon at 3 US centers. Six hours after the procedure, patients were randomized to either stay overnight or be discharged same day. RESULTS: A total of 49 patients were enrolled. Two patients were withdrawn prior to randomization. One patient chose to withdraw after randomization. Of the 22 patients randomized to same-day discharge and the 23 patients randomized the overnight stay, no significant adverse outcomes were reported in either group. Occurrence of adverse events did not differ significantly between the two groups. Procedure time and fluoroscopy time did not significantly differ between groups. CONCLUSIONS: This is the first randomized trial examining the safety of same-day discharge post-cryoballoon ablation. Based on our results, same-day discharge following cryoballoon ablation for paroxysmal AF is a safe option following uncomplicated ablation for PVI. Operators should use their discretion in selecting patients for same-day discharge.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Criocirugía , Venas Pulmonares , Humanos , Alta del Paciente , Resultado del Tratamiento , Venas Pulmonares/cirugía , Criocirugía/métodos , Ablación por Catéter/métodos , Recurrencia
9.
Indian J Ophthalmol ; 71(7): 2733-2738, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37417113

RESUMEN

Purpose: To find out the mean rate of progression (MROP) of visual fields (VF) in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT) using FORUM® Glaucoma Workplace. Methods: Two hundred and one eyes of 105 patients were included in this prospective cohort study. Patients with POAG and OHT were recruited, and VF analysis with 24-2 and or 10-2 was done using SITA standard strategy in Zeiss Humphrey Visual Field Analyzer (HFA). All the previous VFs were identified from FORUM software, and the baseline indices were recorded from the first reliable VF analysis. The present VF analysis was compared to the previous one using FORUM software, and the rate of progression (ROP) in VF was obtained by Guided Progression Analysis. Results: MROP of VF in the POAG group was - 0.085 dB/year, ranging from -2.8 to 2.8 dB/year with a standard deviation (SD) of 0.69. In the OHT group, the MROP of VF was -0.003 dB/year, ranging from - 0.8 to 0.5 dB/year with an SD of 0.27. The MROP of VF in medically treated eyes with POAG was -0.14 dB/year with an SD of 0.61 and in surgically treated eyes was -0.02 dB/year with an SD of 0.78. The overall baseline mean VF index (VFI) was 83.19% and the final mean VFI was 79.80%. There was a statistically significant decrease in the mean VFI value from baseline to the final visit (P-value 0.0005). Conclusion: The mean ROP of VF in the POAG group was -0.085 dB/year and in the OHT group was - 0.003 dB/year.


Asunto(s)
Glaucoma de Ángulo Abierto , Glaucoma , Hipertensión Ocular , Humanos , Campos Visuales , Glaucoma de Ángulo Abierto/diagnóstico , Glaucoma de Ángulo Abierto/cirugía , Presión Intraocular , Estudios Prospectivos , Centros de Atención Terciaria , Trastornos de la Visión , Hipertensión Ocular/diagnóstico , Hipertensión Ocular/epidemiología , Pruebas del Campo Visual , Lugar de Trabajo , Progresión de la Enfermedad
10.
J Am Heart Assoc ; 12(19): e030543, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37750558

RESUMEN

BACKGROUND: Wearable devices may be useful for identification, quantification and characterization, and management of atrial fibrillation (AF). To date, consumer wrist-worn devices for AF detection using photoplethysmography-based algorithms perform only periodic checks when the user is stationary and are US Food and Drug Administration cleared for prediagnostic uses without intended use for clinical decision-making. There is an unmet need for medical-grade diagnostic wrist-worn devices that provide long-term, continuous AF monitoring. METHODS AND RESULTS: We evaluated the performance of a wrist-worn device with lead-I ECG and continuous photoplethysmography (Verily Study Watch) and photoplethysmography-based convolutional neural network for AF detection and burden estimation in a prospective multicenter study that enrolled 117 patients with paroxysmal AF. A 14-day continuous ECG monitor (Zio XT) served as the reference device to evaluate algorithm sensitivity and specificity for detection of AF in 15-minute intervals. A total of 91 857 intervals were contributed by 111 subjects with evaluable reference and test data (18.3 h/d median watch wear time). The watch was 96.1% sensitive (95% CI, 92.7%-98.0%) and 98.1% specific (95% CI, 97.2%-99.1%) for interval-level AF detection. Photoplethysmography-derived AF burden estimation was highly correlated with the reference device burden (R2=0.986) with a mean difference of 0.8% (95% limits of agreement, -6.6% to 8.2%). CONCLUSIONS: Continuous monitoring using a photoplethysmography-based convolutional neural network incorporated in a wrist-worn device has clinical-grade performance for AF detection and burden estimation. These findings suggest that monitoring can be performed with wrist-worn wearables for diagnosis and clinical management of AF. REGISTRATION INFORMATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04546763.


Asunto(s)
Fibrilación Atrial , Aprendizaje Profundo , Humanos , Algoritmos , Fibrilación Atrial/diagnóstico , Electrocardiografía , Estudios Prospectivos , Muñeca
11.
Handb Exp Pharmacol ; (207): 159-76, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22566225

RESUMEN

The structural microheterogeneity of heparin and heparan sulfate is one of the major reasons for the multifunctionality exhibited by this class of molecules. In a physiological context, these molecules primarily exert their effects extracellularly by mediating key processes of cellular cross-talk and signaling leading to the modulation of a number of different biological activities including development, cell proliferation, and inflammation. This structural diversity is biosynthetically imprinted in a nontemplate-driven manner and may also be dynamically remodeled as cellular function changes. Understanding the structural information encoded in these molecules forms the basis for attempting to understand the complex biology they mediate. This chapter provides an overview of the origin of the structural microheterogeneity observed in heparin and heparan sulfate, and the orthogonal analytical methodologies that are required to help decipher this information.


Asunto(s)
Heparina/química , Heparitina Sulfato/química , Heparina/biosíntesis , Heparina/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Relación Estructura-Actividad
12.
Indian J Ophthalmol ; 70(12): 4201-4205, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36453314

RESUMEN

Purpose: This study was conducted to assess the outcomes of bleb needling for the treatment of failure of filtration surgeries in primary glaucoma with a follow-up of six months. Methods: This prospective interventional study included patients with primary glaucoma who underwent trabeculectomy or combined glaucoma and cataract surgery with failed or failing bleb after six weeks of surgery and less than two years. A comprehensive examination including best-corrected visual acuity (BCVA), intraocular pressure (IOP) measurement, gonioscopy, slit-lamp examination, and bleb morphology grading was done. Selected patients underwent a subconjunctival bleb needling with mitomycin C (MMC) (dose 0.2 mg/ml). Postoperatively, patients were followed up on the first, third, and sixth months and were assessed with respect to IOP, need for antiglaucoma medication (AGM), and complications. Results: Sixty eyes of 59 patients were included. Preoperatively, 33.3% of patients were on one AGM, whereas postoperatively at the third month 51.7% and at the sixth month 50% of patients were on no AGM. There was a statistically significant decrease in IOP (P < 0.001) from preoperative (mean: 23.8 ± 7.86 mmHg) to postoperative first month (mean: 19.8 ± 9.08 mmHg), third month (mean: 17.4 ± 5.4 mmHg) and sixth month (mean 16.6 ± 4.39). According to the defined criteria in the current study, we achieved 22 (37.9%) successes, 31 qualified successes (53.4%), and 5 (8.6%) failures. Univariate regression analysis showed a higher failure rate among younger age groups. Gender, laterality, and intraoperative complications were not significant statistically. Conclusion: Bleb needling is a safe and effective procedure for the treatment of failed filtration surgeries.


Asunto(s)
Cirugía Filtrante , Glaucoma , Humanos , Pueblo Asiatico , Glaucoma/cirugía , Estudios Prospectivos
13.
Glycobiology ; 21(9): 1194-205, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21515908

RESUMEN

A series of size-defined low-molecular-weight heparins were generated by regioselective chemical modifications and profiled for their in vitro and in vivo activities. The compounds displayed reduced anti-coagulant activity, demonstrated varying affinities toward angiogenic growth factors (fibroblast growth factor-2, vascular endothelial growth factor and stromal cell-derived factor-1α), inhibited the P-selectin/P-selectin glycoprotein ligand-1 interaction and, notably, exhibited anti-tumor efficacy in a murine melanoma experimental metastasis model. Our results demonstrate that modulating specific sequences, especially the N-domains (-NS or -NH(2) or -NHCOCH(3)) in these polysaccharide sequences, has a major impact on the participation in a diverse range of biological activities. These results also suggest that the 6-O-sulfates, but not the 2-O-sulfates, critically affect the binding of a desulfated derivative to certain angiogenic proteins as well as its ability to inhibit P-selectin-mediated B16F10 melanoma metastases. Furthermore, N-desulfation followed by N-acetylation regenerates the affinity/inhibition properties to different extents in all the compounds tested in the in vitro assays. This systematic study lays a conceptual foundation for detailed structure function elucidation and will facilitate the rational design of targeted heparan sulfate proteoglycan-based anti-metastatic therapeutic candidates.


Asunto(s)
Heparina de Bajo-Peso-Molecular , Neoplasias Pulmonares/tratamiento farmacológico , Melanoma Experimental/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Bibliotecas de Moléculas Pequeñas , Animales , Sitios de Unión , Quimiocina CXCL12/antagonistas & inhibidores , Quimiocina CXCL12/metabolismo , Diseño de Fármacos , Femenino , Factor 2 de Crecimiento de Fibroblastos/antagonistas & inhibidores , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Heparina de Bajo-Peso-Molecular/química , Heparina de Bajo-Peso-Molecular/metabolismo , Heparina de Bajo-Peso-Molecular/farmacología , Ensayos Analíticos de Alto Rendimiento , Hidrólisis , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Glicoproteínas de Membrana/antagonistas & inhibidores , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Neovascularización Patológica/prevención & control , Selectina-P/antagonistas & inhibidores , Selectina-P/metabolismo , Unión Proteica , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Relación Estructura-Actividad , Sulfatos/metabolismo , Resonancia por Plasmón de Superficie , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/metabolismo
14.
N Engl J Med ; 359(25): 2674-84, 2008 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-19052120

RESUMEN

BACKGROUND: In January 2008, the Centers for Disease Control and Prevention began a nationwide investigation of severe adverse reactions that were first detected in a single hemodialysis facility. Preliminary findings suggested that heparin was a possible cause of the reactions. METHODS: Information on clinical manifestations and on exposure was collected for patients who had signs and symptoms that were consistent with an allergic-type reaction after November 1, 2007. Twenty-one dialysis facilities that reported reactions and 23 facilities that reported no reactions were included in a case-control study to identify facility-level risk factors. Unopened heparin vials from facilities that reported reactions were tested for contaminants. RESULTS: A total of 152 adverse reactions associated with heparin were identified in 113 patients from 13 states from November 19, 2007, through January 31, 2008. The use of heparin manufactured by Baxter Healthcare was the factor most strongly associated with reactions (present in 100.0% of case facilities vs. 4.3% of control facilities, P<0.001). Vials of heparin manufactured by Baxter from facilities that reported reactions contained a contaminant identified as oversulfated chondroitin sulfate (OSCS). Adverse reactions to the OSCS-contaminated heparin were often characterized by hypotension, nausea, and shortness of breath occurring within 30 minutes after administration. Of 130 reactions for which information on the heparin lot was available, 128 (98.5%) occurred in a facility that had OSCS-contaminated heparin on the premises. Of 54 reactions for which the lot number of administered heparin was known, 52 (96.3%) occurred after the administration of OSCS-contaminated heparin. CONCLUSIONS: Heparin contaminated with OSCS was epidemiologically linked to adverse reactions in this nationwide outbreak. The reported clinical features of many of the cases further support the conclusion that contamination of heparin with OSCS was the cause of the outbreak.


Asunto(s)
Anticoagulantes/efectos adversos , Sulfatos de Condroitina/efectos adversos , Brotes de Enfermedades , Contaminación de Medicamentos , Heparina/efectos adversos , Anticoagulantes/química , Estudios de Casos y Controles , Edema/inducido químicamente , Edema/epidemiología , Heparina/química , Humanos , Hipotensión/inducido químicamente , Hipotensión/epidemiología , Náusea/inducido químicamente , Náusea/epidemiología , Diálisis Renal , Taquicardia/inducido químicamente , Taquicardia/epidemiología , Estados Unidos/epidemiología , Urticaria/inducido químicamente , Urticaria/epidemiología
15.
N Engl J Med ; 358(23): 2457-67, 2008 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-18434646

RESUMEN

BACKGROUND: There is an urgent need to determine whether oversulfated chondroitin sulfate (OSCS), a compound contaminating heparin supplies worldwide, is the cause of the severe anaphylactoid reactions that have occurred after intravenous heparin administration in the United States and Germany. METHODS: Heparin procured from the Food and Drug Administration, consisting of suspect lots of heparin associated with the clinical events as well as control lots of heparin, were screened in a blinded fashion both for the presence of OSCS and for any biologic activity that could potentially link the contaminant to the observed clinical adverse events. In vitro assays for the activation of the contact system and the complement cascade were performed. In addition, the ability of OSCS to recapitulate key clinical manifestations in vivo was tested in swine. RESULTS: The OSCS found in contaminated lots of unfractionated heparin, as well as a synthetically generated OSCS reference standard, directly activated the kinin-kallikrein pathway in human plasma, which can lead to the generation of bradykinin, a potent vasoactive mediator. In addition, OSCS induced generation of C3a and C5a, potent anaphylatoxins derived from complement proteins. Activation of these two pathways was unexpectedly linked and dependent on fluid-phase activation of factor XII. Screening of plasma samples from various species indicated that swine and humans are sensitive to the effects of OSCS in a similar manner. OSCS-containing heparin and synthetically derived OSCS induced hypotension associated with kallikrein activation when administered by intravenous infusion in swine. CONCLUSIONS: Our results provide a scientific rationale for a potential biologic link between the presence of OSCS in suspect lots of heparin and the observed clinical adverse events. An assay to assess the amidolytic activity of kallikrein can supplement analytic tests to protect the heparin supply chain by screening for OSCS and other highly sulfated polysaccharide contaminants of heparin that can activate the contact system.


Asunto(s)
Anafilaxia/inducido químicamente , Sulfatos de Condroitina/análisis , Sulfatos de Condroitina/farmacología , Activación de Complemento/efectos de los fármacos , Contaminación de Medicamentos , Heparina/química , Calicreínas/efectos de los fármacos , Animales , China , Sulfatos de Condroitina/efectos adversos , Complemento C3a/biosíntesis , Complemento C3a/efectos de los fármacos , Complemento C5a/biosíntesis , Complemento C5a/efectos de los fármacos , Industria Farmacéutica , Femenino , Alemania , Heparina/efectos adversos , Humanos , Hipotensión/inducido químicamente , Calicreínas/metabolismo , Persona de Mediana Edad , Sus scrofa , Estados Unidos , United States Food and Drug Administration
16.
Heart Fail Clin ; 7(2): 207-13, viii, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21439499

RESUMEN

Frequent shocks from an implantable defibrillator (ICD) can have adverse cardiac affects and lead to increased pain, anxiety, and a decreased quality of life. Pharmacologic attempts and ICD reprogramming strategies aimed at reducing ICD shocks have modest results, with frequent discontinuation of medicines because of side effects. Ventricular tachycardia (VT) ablation is recommended in the treatment of patients with frequent ICD shocks caused by VT. VT ablation may also be considered in patients with an initial ICD shock and as prophylactic treatment in patients with a history of sustained VT who are undergoing ICD implant.


Asunto(s)
Ablación por Catéter/métodos , Desfibriladores Implantables/estadística & datos numéricos , Taquicardia Ventricular/cirugía , Antagonistas Adrenérgicos beta/uso terapéutico , Algoritmos , Mapeo del Potencial de Superficie Corporal/métodos , Desfibriladores Implantables/efectos adversos , Humanos , Taquicardia Ventricular/tratamiento farmacológico , Taquicardia Ventricular/terapia
17.
J Innov Card Rhythm Manag ; 12(2): 4413-4420, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33654573

RESUMEN

Pulmonary vein isolation (PVI) is widely used for the ablation of atrial fibrillation, with prior reports suggesting good efficacy. Due to the widespread use of three-dimensional electroanatomic mapping systems and advances in intracardiac echocardiography, fluoroless ablation has been made possible. Fluoroless ablation with a cryoballoon (CB), however, has not been widely performed because of the need to prove occlusion of the vein with contrast dye and fluoroscopy. The objective of this study is to show that CB ablation can be performed safely and effectively without fluoroscopy. A dual-center, case-control study was performed of patients undergoing CB PVI with a fluoroless approach and a control group with traditional fluoroscopic techniques. The absence of color-flow Doppler signals around the periphery of the CB on intracardiac echocardiography and an increase in mean pressure by 5 mmHg, loss of the A-wave, and an increase in the V-wave as measured with continuous-wave pressure monitoring were adopted as indicators of vein occlusion in the absence of fluoroscopy. Temperature at 30 seconds, minimum temperature, time to isolation, procedure length, and complications were evaluated. During the study period of November 15, 2018 to November 15, 2019, a total of 100 patients underwent CB PVI at the participating centers. A total of 50 patients were enrolled in the fluoroless arm [35 men (70%), mean age: 64.9 ± 12 years, mean left atrium size: 44.2 ± 16 mL/m2, left ventricular ejection fraction: 61% ± 5%], while 50 patients were enrolled in the control arm with similar characteristics. Four hundred forty-one 441 PVs were evaluated in the study cohort compared to 339 PVs in the control arm. When comparing fluoroless and traditional techniques, the mean temperature at 30 seconds was -31.7°C ± 6°C versus -32.8°C ± 5°C (p = 0.037), the minimum temperature was -47.4°C ± 6°C versus -47.7°C ± 9°C (p = 0.677), the time to isolation was 56.8 ± 28 seconds versus 74.8 ± 45 seconds (p = 0.212), and the procedure time was 102.2 ± 27.3 seconds versus 104.5 ± 16.9 seconds (p = 0.6436). Ultimately, this proof-of-concept study revealed that fluoroless ablation can be performed with success and efficiency outcomes similar to those of a traditional ablation approach. This suggests that the ablation of atrial fibrillation with CB can be performed safely and effectively without the use of fluoroscopy by experienced operators.

18.
Anal Chem ; 81(21): 8900-7, 2009 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-19817480

RESUMEN

With the rapid growth of complex heterogeneous biological molecules, effective techniques that are capable of rapid characterization of biologics are essential to ensure the desired product characteristics. To address this need, we have developed a method for analysis of intact glycoproteins based on high-resolution capillary electrophoretic separation coupled to an LTQ-FT mass spectrometer. We evaluated the performance of this method on the alpha subunit of mouse cell line-derived recombinant human chorionic gonadotrophin (r-alpha hCG), a protein that is glycosylated at two sites and is part of the clinically relevant gonadotrophin family. Analysis of r-alpha hCG, using capillary electrophoresis (CE) with a separation time under 20 min, resulted in the identification of over 60 different glycoforms with up to nine sialic acids. High-resolution CE-Fourier transform mass spectrometry (FT-MS) allowed separation and analysis of not only intact glycoforms with different numbers of sialic acids but also intact glycoforms that differed by the number and extent of neutral monosaccharides. The high mass resolution of the FT-MS enabled a limited mass range to be targeted for the examination of the protein glycoforms, simplifying the analysis without sacrificing accuracy. In addition, the limited mass range resulted in a fast scan speed that enhanced the reproducibility of the relative quantitation of individual glycoforms. The intact glycoprotein analysis was complemented with the analysis of the tryptic glycopeptides and glycans of r-alpha hCG to enable the assignment of glycan structures to individual sites, resulting in a detailed characterization of the protein. Samples of r-alpha hCG obtained from a CHO cell line were also analyzed and briefly shown to be significantly different from the murine cell line product. Taken together, the results suggest that the CE coupled to high-resolution FT-MS can be one of the effective tools for in-process monitoring as well as for final product characterization.


Asunto(s)
Electroforesis Capilar/métodos , Hormonas Glicoproteicas de Subunidad alfa/análisis , Espectrometría de Masas/métodos , Animales , Células CHO , Línea Celular , Cricetinae , Cricetulus , Análisis de Fourier , Glicopéptidos/análisis , Hormonas Glicoproteicas de Subunidad alfa/metabolismo , Humanos , Ratones , Polisacáridos/análisis , Proteínas Recombinantes/análisis , Proteínas Recombinantes/metabolismo , Tripsina/metabolismo
19.
J Cardiovasc Electrophysiol ; 20(12): 1413-5, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19656249

RESUMEN

Transvenous pacemaker and defibrillator (PM-D) lead failure is an important clinical problem. Lead extraction is routinely performed in patients with transvenous pacemaker and defibrillator (PM-D) infections. The management of sterile PM-D leads that have failed or are no longer required is less uniform. While extraction of excess or failed sterile PM-D leads is often advocated, the risk of lead extraction must be weighed against the risk of abandoning these leads. There are no randomized trials comparing lead extraction with abandoning sterile leads in this setting. What then are the data that are used to advocate the extraction of excess or failed, sterile chronically implanted PM-D leads, and are the data adequate to make this recommendation?


Asunto(s)
Desfibriladores Implantables/estadística & datos numéricos , Remoción de Dispositivos/estadística & datos numéricos , Electrodos Implantados/estadística & datos numéricos , Marcapaso Artificial/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Falla de Prótesis , Humanos , Incidencia , Complicaciones Posoperatorias/prevención & control , Medición de Riesgo
20.
Int J Oncol ; 32(6): 1237-43, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18497985

RESUMEN

Merlin, the protein product of the neurofibromatosis type 2 gene (NF2) acts as a tumor suppressor in mice and humans. In this study, melanoma B16F10 cells were engineered to overexpress the NF2 gene by establishing stable transductants. A cell line overexpressing Merlin (B16F10-M) was generated. When compared to the parental cells, the B16F10-M cells demonstrated differences in their cell surface organization. The overexpressing strain changed its ability to grow in soft agar as well as its cell motility properties. B16F10-M cells were then examined in the in vivo mouse melanoma tumor growth and tumor metastasis models. While tumor growth was marginally affected, the presence of increased Merlin severely reduced the metastastatic ability of the cells. When isolated using specific enzymes with distinct substrate specificity, the cell surface heparan sulfate glycosaminoglycans (HSGAGs) from the overexpressing B16F10-M cells, inhibited the metastatic properties of the parental B16F10 cells. The results obtained provide a causal link between the reorganization/changes to the cell surface HSGAGs by the overexpression of Merlin and the inhibition of the metastatic activity of the mouse melanoma B16F10 cells in vivo.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/fisiología , Heparitina Sulfato/metabolismo , Neoplasias Pulmonares/prevención & control , Melanoma Experimental/prevención & control , Neurofibromina 2/genética , Animales , Western Blotting , Adhesión Celular , Ensayo de Unidades Formadoras de Colonias , Neoplasias Pulmonares/secundario , Masculino , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/secundario , Ratones , Ratones Endogámicos C57BL , Transfección , Células Tumorales Cultivadas
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