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1.
Environ Pollut ; 347: 123706, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38467367

RESUMEN

Fly ash consists of a considerable amount of hazardous elements with high mobility, posing substantial environmental risks during storage in surface impoundments and landfills. This hinders its efficient reuse in construction or material industries. To enhance the versatility of fly ash applications, a novel surface modification technique, termed SuMo, has been developed to create a hydrophobic polysulfide polymer coating on the surface of fly ash particles. The physicochemical properties of SuMo fly ash samples were examined using atomic force microscopy (AFM), environmental scanning electron microscopy (ESEM), thermal gravimetric analysis (TGA), Fourier Transform Infrared spectroscopy (FTIR), and leaching of hazardous elements was tested under practical environmental conditions (pH 4-12) based on the EPA's leaching environmental assessment framework (LEAF). The successful coating of polysulfide polymer on fly ash surface was verified through an increased percentage of C, S, and O in elemental mapping, coupled with the identification of S-O, CO, and C-H functional groups consistent with the chemical structure of polysulfide polymer. While the SuMo fly ash particles maintained their spherical shape, they exhibited increased surface roughness, robust hydrophobicity, and thermal stability up to 250 °C. Notably, owing to the coating's resilience against water leaching, the SuMo fly ash demonstrated a substantial reduction (up to 60-fold) in leachate concentrations of multiple concerning elements, including B, Be, Ba, Mn, Zn, As, Cr, Hg, etc., under various pH conditions compared to the uncoated fly ash. Furthermore, the polysulphide polymer coating effectively prevented Hg volatilization from fly ash below 163 °C. This study highlights the efficacy of the developed polysulfide polymer coating in mitigating the diffusion of hazardous elements from fly ash, thereby enhancing its potential reutilization in material, construction, and agriculture industries.


Asunto(s)
Ceniza del Carbón , Mercurio , Sulfuros , Ceniza del Carbón/química , Microscopía Electrónica de Rastreo , Agricultura
2.
Int J Biol Macromol ; 128: 655-664, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30708008

RESUMEN

The synthesis of a novel composite adsorbent prepared from coir pith activated carbon (CPAC), chitosan and sodium dodecyl sulphate (SDS, an anionic surfactant) is reported. The characterisation of the composite was done using SEM, XRD, UV-visible and IR spectroscopy studies. The effectiveness of the composite was made for the removal of a toxic cationic dye, malachite green (MG) from waste water based on adsorption studies. The reaction conditions for the adsorption studies were optimized based on initial dye concentration, dose rate, reaction time, pH and temperature. Langmuir and Freundlich isotherm models were adopted to study the mechanism of adsorption. The adsorption process was found to follow pseudo second order kinetics. The results of the present study indicate that the CPAC based composite could be an effective low cost adsorbent for the removal of MG from waste water.


Asunto(s)
Quitosano/química , Colorantes de Rosanilina/química , Colorantes de Rosanilina/aislamiento & purificación , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Dodecil Sulfato de Sodio/química , Soluciones , Propiedades de Superficie , Termodinámica , Factores de Tiempo , Aguas Residuales/química
3.
Transplant Proc ; 49(10): 2406-2408, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29198691

RESUMEN

Organ donor criteria continue to be extended in an attempt to meet growing demands. Patients with continuous-flow left ventricular assist devices are one group of potential donors being considered. One concern with this group is the effect of continuous flow for a prolonged duration, as opposed to normal pulsatile flow, on end-organ function. We report the 1st case of a liver transplantation from a donor who had a continuous-flow left ventricular assist device for 9 months. The recipient was a 69-year-old woman with a history of cryptogenic cirrhosis and hepatocellular carcinoma. The transplantation was complicated by moderate acute cellular rejection as well as biliary obstruction requiring sphincterotomy and stent placement. After management of those complications, the patient's liver function tests returned to normal values and remained stable at her 6-month post-transplantation follow-up. This case shows that organ transplantation from a donor with a continuous-flow left ventricular assist device for a prolonged period can be performed successfully.


Asunto(s)
Corazón Auxiliar , Fallo Hepático/cirugía , Trasplante de Hígado/métodos , Donantes de Tejidos , Anciano , Carcinoma Hepatocelular/complicaciones , Femenino , Humanos , Cirrosis Hepática/complicaciones , Fallo Hepático/etiología , Neoplasias Hepáticas/complicaciones , Masculino , Persona de Mediana Edad , Donantes de Tejidos/provisión & distribución , Resultado del Tratamiento
4.
Clin Transplant ; 31(11)2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28881060

RESUMEN

The number of nonrenal solid-organ transplants increased substantially in the last few decades. Many of these patients develop renal failure and receive kidney transplantation. The aim of this study was to evaluate patient and kidney allograft survival in primary, repeat, and kidney-after-nonrenal organ transplantation using national data reported to United Network for Organ Sharing (UNOS) from January 2000 through December 2014. Survival time for each patient was stratified into the following: Group A (comparison group)-recipients of primary kidney transplant (178 947 patients), Group B-recipients of repeat kidney transplant (17 819 patients), and Group C-recipients of kidney transplant performed after either a liver, heart, or lung transplant (2365 patients). We compared survivals using log-rank test. Compared to primary or repeat kidney transplant, patient and renal allograft survival was significantly lower in those with previous nonrenal organ transplant. Renal allograft and patient survival after liver, heart, or lung transplants are comparable. Death was the main cause of graft loss in patients who had prior nonrenal organ transplant.


Asunto(s)
Bases de Datos Factuales , Rechazo de Injerto/mortalidad , Fallo Renal Crónico/cirugía , Trasplante de Riñón/mortalidad , Trasplante de Órganos/mortalidad , Complicaciones Posoperatorias/mortalidad , Adulto , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/etiología , Supervivencia de Injerto , Humanos , Pruebas de Función Renal , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad , Trasplante de Órganos/efectos adversos , Pronóstico , Sistema de Registros , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo
5.
J Pain Res ; 10: 709-736, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28435313

RESUMEN

Despite enormous progress in the field of pain management over the recent years, pain continues to be a highly prevalent medical condition worldwide. In the developing countries, pain is often an undertreated and neglected aspect of treatment. Awareness issues and several misconceptions associated with the use of analgesics, fear of adverse events - particularly with opioids and surgical methods of analgesia - are major factors contributing to suboptimal treatment of pain. Untreated pain, as a consequence, is associated with disability, loss of income, unemployment and considerable mortality; besides contributing majorly to the economic burden on the society and the health care system in general. Available guidelines suggest that a strategic treatment approach may be helpful for physicians in managing pain in real-world settings. The aim of this manuscript is to propose treatment recommendations for the management of different types of pain, based on the available evidence. Evidence search was performed by using MEDLINE (by PubMed) and Cochrane databases. The types of articles included in this review were based on randomized control studies, case-control or cohort studies, prospective and retrospective studies, systematic reviews, meta-analyses, clinical practice guidelines and evidence-based consensus recommendations. Articles were reviewed by a multidisciplinary expert panel and recommendations were developed. A stepwise treatment algorithm-based approach based on a careful diagnosis and evaluation of the underlying disease, associated comorbidities and type/duration of pain is proposed to assist general practitioners, physicians and pain specialists in clinical decision making.

6.
Eye (Lond) ; 29(12): 1538-44, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26228291

RESUMEN

PURPOSE: To compare 2.0 mg ranibizumab (RBZ) injections with 0.5 mg RBZ for eyes with center-involved diabetic macular edema (DME) and a central subfield thickness (CFT) of ≥250 µm on time-domain optical coherence tomography.DesignRandomized, controlled, multicenter clinical trial. METHODS: Eligible eyes were randomized in a 1:1 ratio to 0.5 mg (n=77) or 2.0 mg (n=75) RBZ. Study eyes received 6-monthly injections.Main outcome measuresThe primary outcome measure was the mean change in best corrected visual acuity (BCVA) at month 6. Secondary outcomes included the incidence and severity of systemic and ocular adverse events and the mean change in CFT from baseline. RESULTS: In all, 152 eyes (152 patients) were randomized in the study. At month 6, the mean improvement from baseline BCVA was +9.43 letters in the 0.5 mg RBZ group and +7.01 letters in the 2.0 mg RBZ group (P=0.161). At month 6, one death occurred in the 0.5 mg RBZ group and three deaths in the 2.0 mg RBZ group, all due to myocardial infarction in subjects with a prior history of heart disease. Mean CFT was reduced by 168.58 µm in the 0.5 mg RBZ group and by 159.70 µm in the 2.0 mg RBZ group (P=0.708). CONCLUSIONS: There was no statistically significant difference in the mean number of letters gained between the 0.5 and 2.0 mg RBZ groups through month 6. In this DME study population, high-dose RBZ does not appear to provide additional benefit over 0.5 mg RBZ.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Retinopatía Diabética/tratamiento farmacológico , Edema Macular/tratamiento farmacológico , Ranibizumab/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/fisiopatología , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intravítreas , Edema Macular/diagnóstico , Edema Macular/fisiopatología , Masculino , Persona de Mediana Edad , Retina/patología , Tomografía de Coherencia Óptica , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores
7.
Transpl Infect Dis ; 17(4): 613-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26073334

RESUMEN

We describe the first reported case, to our knowledge, of disseminated pneumococcal infection involving a left ventricular assist device (LVAD). The management of this infection was extremely challenging, requiring multiple surgical debridements, LVAD removal, and prolonged courses of antibiotics. The Streptococcus pneumoniae isolate was found to be serotype 19F, which is included in both the pneumococcal polysaccharide and conjugate vaccines. This report highlights the importance of routine screening for up-to-date vaccination in patients who undergo LVAD implantation.


Asunto(s)
Corazón Auxiliar , Infecciones Neumocócicas/diagnóstico , Complicaciones Posoperatorias/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Infecciones Neumocócicas/etiología
8.
Forensic Sci Int Genet ; 17: 122-128, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25966466

RESUMEN

DNA-based individual identification and RNA-based tissue identification represent two commonly-used tools in forensic investigation, aiming to identify crime scene sample donors and helping to provide links between DNA-identified sample donors and criminal acts. Currently however, both analyses are typically performed separately. In this proof-of-principle study, we developed an approach for the simultaneous analysis of forensic STRs, amelogenin, and forensic mRNAs based on parallel targeted DNA/RNA sequencing using the Ion Torrent Personal Genome Machine(®) (PGM™) System coupled with the AmpliSeq™ targeted amplification. We demonstrated that 9 autosomal STRs commonly used for individual identification (CSF1PO, D16S539, D3S1358, D5S818, D7S820, D8S1179, TH01, TPOX, and vWA), the AMELX/AMELY system widely applied for sex identification, and 12 mRNA markers previously established for forensic tissue identification (ALAS2 and SPTB for peripheral blood, MMP10 and MMP11 for menstrual blood, HTN3 and STATH for saliva, PRM1 and TGM4 for semen, CYP2B7P1 and MUC4 for vaginal secretion, CCL27 and LCE1C for skin) together with two candidate reference mRNA markers (HPRT1 and SDHA) can all be successfully combined. Unambiguous mRNA-based tissue identification was achieved in all samples from all forensically relevant tissues tested, and STR sequencing analysis of the tissue sample donors was 100% concordant with conventional STR profiling using a commercial kit. Successful STR analysis was obtained from 1ng of genomic DNA and mRNA analysis from 10ng total RNA; however, sensitivity limits were not investigated in this proof-of-principle study and are expected to be much lower. Since dried materials with noticeable RNA degradation and small DNA/RNA amplicons with high-coverage sequencing were used, the achieved correct individual and tissue identification demonstrates the suitability of this approach for analyzing degraded materials in future forensic applications. Overall, our study demonstrates the feasibility of simultaneously obtaining multilocus STR, amelogenin, and multilocus mRNA information for combined individual and tissue identification from a small sample of degraded biological material. Moreover, our study marks the first step towards combining many DNA/RNA markers for various forensic purposes to increase the effectiveness of molecular forensic analysis and to allow more forensically relevant information to be obtained from limited forensic material.


Asunto(s)
Amelogenina/genética , ADN/genética , Genética Forense/métodos , Repeticiones de Microsatélite , ARN Mensajero/genética , Análisis de Secuencia de ADN/métodos , Análisis de Secuencia de ARN/métodos , ADN/análisis , Estudios de Factibilidad , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Masculino , ARN Mensajero/análisis
10.
J Postgrad Med ; 57(2): 168-75, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21654148

RESUMEN

Obstructive sleep apnea (OSA) has long been recognized as a disorder characterized by snoring and frequent cessations of breathing resulting in fragmentation of sleep, which eventually leads to cumulative sleep debt in affected patients. Until two decades ago, snoring and apneas drew attention mainly as a social curiosity and sleep apnea was not thought of as a serious disorder with multisystem involvement. Impairment of quality of work and high incidence of motor vehicle accidents associated with OSA were recognized toward the end of the last century. Since the turn of this millennium physicians have become increasingly aware of the various cardiovascular complications, metabolic disturbances, and neuropsychologic deficits. It has become very clear in the last decade that patients with OSA have a high recurrence of atrial fibrillation after elective cardioversion if their sleep apnea is not treated with continuous positive airway pressure (CPAP). Poor control of diabetes mellitus and resistant hypertension in the setting of OSA has also been recognized and significant progress in our understanding in this area has been accomplished. Unless physicians include sleep in their system review, many cases will go undiagnosed, which will eventually result in cardiovascular complications. Patients are also not readily forthcoming with the symptoms of sleep apnea, as they often assume that symptoms, such as snoring and daytime sleepiness, are not something serious to be discussed with their physician. In this review, the characteristics, the pathophysiology, and epidemiology of OSA are discussed. Furthermore, the mechanisms by which OSA affects the cardiovascular, endocrine, and metabolic functions have been explored.


Asunto(s)
Apnea Obstructiva del Sueño/complicaciones , Arritmias Cardíacas/etiología , Trastornos Cerebrovasculares/etiología , Humanos , Hipertensión Pulmonar/etiología , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/fisiopatología
11.
Water Sci Technol ; 62(10): 2263-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21076211

RESUMEN

Reducing water consumption in bioethanol production conserves an increasingly scarce natural resource, lowers production costs, and minimizes effluent management issues. The suitability of cooling tower blow down water for reuse in fermentation was investigated as a means to lower water consumption. Extensive chemical characterization of the blow down water revealed low concentrations of toxic elements and total dissolved solids. Fermentation carried out with cooling tower blow down water resulted in similar levels of ethanol and residual glucose as a control study using deionized water. The study noted good tolerance by yeast to the specific scale and corrosion inhibitors found in the cooling tower blow down water. This research indicates that, under appropriate conditions, reuse of blow down water from cooling towers in fermentation is feasible.


Asunto(s)
Biocombustibles/análisis , Conservación de los Recursos Naturales/métodos , Etanol/metabolismo , Agua , Etanol/química , Fermentación , Industrias
12.
Can J Cardiol ; 25(3): e73-7, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19279990

RESUMEN

BACKGROUND: In contrast to the homogeneously distributed deformation properties within the left ventricle, the right ventricular (RV) free wall (RVFW) shows a more inhomogeneous distribution. It has been demonstrated that pulmonary hypertension (PH) results in significant RVFW mechanical delay. OBJECTIVE: To assess the effect of the degree of pulmonary arterial systolic pressure on the RVFW strain gradient and on myocardial velocity generation. METHODS: Peak longitudinal strain and velocity data were collected from three different segments (basal, mid- and apical) of the RVFW in 17 normal individuals and 31 PH patients. RESULTS: A total of 144 RV wall segments were analyzed. RVFW strain values in individuals without PH were higher in the mid and apical segments than in the basal segment. In contrast, RVFW strain in PH patients was higher in basal segments and diminished toward the apex. In terms of RVFW velocities, both groups showed decremental values from basal to apical segments. Basal and mid-RVFW velocities were significantly lower in PH patients than in individuals without PH. CONCLUSIONS: PH results in significant alterations of strain and velocity generation that occurs along the RVFW. Of these abnormalities, the reduction in strain from the mid and apical RVFW segments was most predictive of PH. It is important to be aware of these differences in strain generation when studying the effect of PH on the right ventricle. Additional studies are required to determine whether these differences are due to RV remodelling.


Asunto(s)
Ecocardiografía Doppler/métodos , Ventrículos Cardíacos/fisiopatología , Hipertensión Pulmonar/fisiopatología , Adulto , Anciano , Diagnóstico por Imagen de Elasticidad , Femenino , Humanos , Hipertensión Pulmonar/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Curva ROC , Estrés Mecánico , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/fisiopatología , Remodelación Ventricular
13.
J Orthop Surg (Hong Kong) ; 16(2): 175-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18725667

RESUMEN

PURPOSE: To determine the role of qualitative cultures for detecting infection in open tibial fractures. METHODS: From January 2003 to December 2004, 95 men and 13 women (mean age, 34 years) with open tibial fractures in one or both limbs and without any other sites of infection were prospectively studied. Patients who had been treated with intravenous or oral antibiotics before presentation and/or had undergone debridement or other surgery were excluded. RESULTS: Infection was not correlated with age, sex, interval from injury to debridement, and cause of fracture. The association of infection with predebridement cultures was stronger (odds ratio=12.5) than that with postdebridement cultures (odds ratio=4.7). CONCLUSION: Pre- and post-debridement cultures have a role in detecting infection in open tibial fractures. For detecting infection, predebridement cultures have better sensitivity, while postdebridement cultures have better specificity.


Asunto(s)
Fracturas Abiertas/microbiología , Infección de Heridas/microbiología , Adulto , Distribución de Chi-Cuadrado , Desbridamiento , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Riesgo
14.
Postgrad Med J ; 84(987): 40-5, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18230750

RESUMEN

BACKGROUND: Right ventricular (RV) fractional area change and tricuspid annular plane systolic excursion (TAPSE) are recognised methods for assessing RV function. However, the way in which these variables are affected by varying degrees of pulmonary hypertension (PH) has not been well characterised. METHODS: RV end-systolic area (RVESA), RV end-diastolic area (RVEDA), pulmonary artery systolic pressure (PASP) and TAPSE were collected from a database of 190 patients who had been referred to the PH clinic for evaluation. RESULTS: The mean (SD) age of the study population was 56 (17) years; 82 men were included with a mean (SD) PASP of 54 (33) mm Hg (range 16-150), RVESA of 14 (9) cm(2), RVEDA of 24 (9) cm(2), RV fractional area change of 44 (18)% and TAPSE of 2.06 (0.69) cm. Receiver-operating characteristic curves identified TAPSE <2.01 cm, RV fractional area change <40.9%, RVESA >12.3 cm(2) and RVEDA >23.4 cm(2) as abnormal values with PH. Finally stratification of patients into sub-groups according to their PASP allowed means and standard deviations to be reported for each echocardiographic variable. CONCLUSION: This analysis provides a range of normal variables of RV size and function, not previously published, that can be used in routine evaluation and follow-up of patients with PH.


Asunto(s)
Ventrículos Cardíacos/diagnóstico por imagen , Hipertensión Pulmonar/fisiopatología , Función Ventricular Derecha/fisiología , Ecocardiografía Doppler , Femenino , Ventrículos Cardíacos/fisiopatología , Humanos , Hipertensión Pulmonar/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
15.
PDA J Pharm Sci Technol ; 61(1): 51-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17390704

RESUMEN

The purpose of this study was to evaluate the effect of processing and storage on the moisture content of two commercially available, 13-mm lyophilization stoppers designated as low moisture (LM) and high moisture (HM) uptake stoppers. The stopper moisture studies included the effect of steam sterilization time, drying time and temperature, equilibrium moisture content, lyophilization and moisture transfer from stopper to a model-lactose lyophilized cake. Results indicated that both stoppers absorbed significant amounts of moisture during sterilization and that the HM stopper absorbed significantly more water than the LM stopper. LM and HM stoppers required approximately 2 and 8 h drying at 105 degrees C, respectively, to achieve final moisture content of not more than 0.5 mg/stopper. Following drying, stopper moisture levels equilibrated rapidly to ambient storage conditions. The apparent equilibrium moisture level was approximately 7 times higher in the HM versus LM stopper. Freeze-drying had minimal effect on the moisture content of dried stoppers. Finally, moisture transfer from the stopper to the lyophilized product is dependent on the initial stopper water content and storage temperature. To better quantify the ramifications of stopper moisture, projections of moisture uptake over the shelf life of a drug product were calculated based on the product-contact surface area of stoppers. Attention to stopper storage conditions prior to use, in addition to processing steps, are necessary to minimize stability issues especially in low-fill, mass lyophilized products.


Asunto(s)
Liofilización , Preparaciones Farmacéuticas , Esterilización , Agua/análisis , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Elastómeros/química , Liofilización/normas , Cinética , Preparaciones Farmacéuticas/análisis , Preparaciones Farmacéuticas/normas , Medición de Riesgo , Esterilización/normas , Temperatura , Factores de Tiempo , Volumetría
16.
J Orthop Surg (Hong Kong) ; 13(1): 83-7, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15872408

RESUMEN

Benign fibrous histiocytoma is such a rare tumour that only a few cases have been reported in the literature. A patient with an apparently benign lesion of the distal radius, along with congenital dislocation of the radial head, was presented at St. John's Medical College Hospital in Bangalore, India. Pain was the chief symptom. There were histological features of non-ossifying fibroma in the lesion. Because of its unusual radiological appearance and atypical clinical course, the lesion was diagnosed as fibrous histiocytoma. In this case report, we review similar cases in the literature and discuss an unusual association with congenital dislocation of the radial head.


Asunto(s)
Amputación Quirúrgica , Neoplasias Óseas/cirugía , Histiocitoma Fibroso Benigno/cirugía , Recurrencia Local de Neoplasia/cirugía , Procedimientos Ortopédicos/efectos adversos , Adolescente , Neoplasias Óseas/complicaciones , Neoplasias Óseas/patología , Peroné/trasplante , Histiocitoma Fibroso Benigno/complicaciones , Histiocitoma Fibroso Benigno/patología , Humanos , Luxaciones Articulares , Masculino , Recurrencia Local de Neoplasia/etiología , Procedimientos Ortopédicos/métodos , Radio (Anatomía) , Reoperación , Extremidad Superior
17.
J Am Soc Echocardiogr ; 14(11): 1119-26, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11696838

RESUMEN

The objective of this study was to determine whether Doppler echocardiography is useful in assessing the effects of pericardiectomy in patients with constrictive pericarditis by studying the postoperative change in the respiratory variation of mitral inflow and pulmonary venous Doppler flows. The study population consisted of 35 cases with surgically proven constrictive pericarditis. Thirty-five patients had preoperative Doppler echocardiography, whereas 4 patients died of non-cardiac causes and 1 patient had a heart transplant before follow-up. Postoperative studies were performed at a mean of 1081 +/- 84 days (range 120-2700 days) after pericardiectomy. The mean (+/- SD) respiratory variation changed after surgery from a baseline value of 17% +/- 14% to 8% +/- 8% for peak mitral E velocity (P <.01); from 25% +/- 18% to 7% +/- 13% (P <.001) for pulmonary venous (PV) peak diastolic flow velocity, and from 21% +/- 13% to 11% +/- 13% (P =.009) for PV peak systolic flow velocity. The 23 patients who became asymptomatic after surgery had a significantly lower mean mitral and PV respiratory variation than the 7 patients who were NYHA class II (4% +/- 4% and 6% +/- 4% vs 21% +/- 6% and 19% +/- 10%, respectively, P <.0001 for both). Pulsed Doppler echocardiographic assessment of respiratory variation is useful for evaluating the outcome of pericardiectomy.


Asunto(s)
Ecocardiografía Doppler , Válvula Mitral/fisiopatología , Pericardiectomía , Pericarditis Constrictiva/diagnóstico por imagen , Circulación Pulmonar/fisiología , Venas Pulmonares/fisiopatología , Anciano , Velocidad del Flujo Sanguíneo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral/diagnóstico por imagen , Pericarditis Constrictiva/fisiopatología , Pericarditis Constrictiva/cirugía , Venas Pulmonares/diagnóstico por imagen , Respiración
18.
Am J Cardiol ; 87(1): 86-94, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11137840

RESUMEN

This study assesses how the newer modalities of tissue Doppler echocardiography and color M-mode flow propagation compare with respiratory variation of Doppler flow in distinguishing between constrictive pericarditis and restrictive cardiomyopathy. We studied 30 patients referred for further evaluation of diastolic function who had a diagnosis of constrictive pericarditis or restrictive cardiomyopathy established by diagnostic tests, including clinical assessment, magnetic resonance imaging, cardiac catheterization, endomyocardial biopsy, and surgical findings. Nineteen patients had constrictive pericarditis and 11 had restrictive cardiomyopathy. We performed 2-dimensional transesophageal echocardiography combined with pulsed-wave Doppler of the pulmonary veins and mitral inflow with respiratory monitoring, tissue Doppler echocardiography of the lateral mitral annulus, and color M-mode flow propagation of left ventricular filling. Respiratory variation of the mitral inflow peak early (peak E) velocity of > or =10% predicted constrictive pericarditis with 84% sensitivity and 91% specificity and variation in the pulmonary venous peak diastolic (peak D) flow velocity of > or =18% distinguished constriction with 79% sensitivity and 91% specificity. Using tissue Doppler echocardiography, a peak early velocity of longitudinal expansion (peak Ea) of > or =8.0 cm/s differentiated patients with constriction from restriction with 89% sensitivity and 100% specificity. A slope of > or =100 cm/s for the first aliasing contour in color M-mode flow propagation predicted patients with constriction with 74% sensitivity and 91% specificity. Thus, the newer methods of tissue Doppler echocardiography and color M-mode flow propagation are equivalent and complimentary with Doppler respiratory variation in distinguishing between constrictive pericarditis and restrictive cardiomyopathy. The additive role of the new methods needs to be established in difficult cases of constrictive pericarditis where respiratory variation may be absent or decreased.


Asunto(s)
Cardiomiopatía Restrictiva/diagnóstico por imagen , Ecocardiografía Doppler/métodos , Pericarditis Constrictiva/diagnóstico por imagen , Adulto , Anciano , Circulación Coronaria/fisiología , Diagnóstico Diferencial , Ecocardiografía Transesofágica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Circulación Pulmonar/fisiología , Respiración , Sensibilidad y Especificidad
19.
Am Heart J ; 138(5 Pt 1): 880-9, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10539819

RESUMEN

BACKGROUND: Two-dimensional transthoracic echocardiography with respiratory monitoring has been used to characterize diseases that impair diastolic function. Transesophageal echocardiography (TEE) has emerged as a complementary technique to evaluate patients with these diseases. The purpose of this study was to evaluate in a large clinical practice the utility of TEE with respiratory monitoring for classification of patients with diastolic dysfunction. METHODS: Over a 9-year period TEE was used to examine 192 patients referred to an echocardiography laboratory for additional evaluation of abnormal diastolic function. We performed pulsed-wave Doppler TEE of the left ventricular inflow and pulmonary veins and respiratory monitoring to categorize patients as showing restrictive physiologic features, constriction with or without effusion, mixed constriction and restriction, abnormal relaxation, pseudonormalization, large pericardial effusion or tamponade, or normal diastolic function. RESULTS: Patients with diastolic dysfunction underwent 3% of the total number of transesophageal studies conducted during the study period. Among the 192 patients referred for TEE, abnormal diastolic function was found in 181 (94%); 11 (6%) had normal diastolic function. Seventy-one (39%) of the 181 patients had restrictive physiologic features. Constrictive pericarditis was found in 54 (30%) of the patients and was confirmed for all 31 patients who underwent pericardiectomy. Mixed constriction and restriction was present in 21 (12%) of the patients. The other 35 patients (19%) had abnormal relaxation, pseudonormalization, or large pericardial effusion or tamponade. The cause of diastolic dysfunction was idiopathic for 32% of the patients, previous cardiac operation for 26%, cardiac amyloidosis for 23%, radiation therapy for 11%, and hypertension or advanced ischemic heart disease for 8%. CONCLUSION: Two-dimensional and Doppler TEE with respiratory monitoring is useful in categorizing patients with impaired diastolic function, primarily into those with restrictive physiologic features or constrictive pericarditis.


Asunto(s)
Ecocardiografía Doppler de Pulso , Ecocardiografía Transesofágica , Ventrículos Cardíacos/diagnóstico por imagen , Contracción Miocárdica , Disfunción Ventricular Izquierda/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Velocidad del Flujo Sanguíneo , Cateterismo Cardíaco , Ecocardiografía Transesofágica/métodos , Femenino , Trasplante de Corazón , Ventrículos Cardíacos/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/fisiopatología , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Disfunción Ventricular Izquierda/fisiopatología
20.
Pharm Res ; 16(4): 562-8, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10227713

RESUMEN

PURPOSE: To determine the cloud point of a variety of nonionic surfactants and to search for means to raise the surfactant cloud point in liquid formulations. METHODS: Cloud points of nonionic surfactants were determined visually in a water bath. Organic compounds, many of which have been used as pharmaceutical excipients, were tested initially for effect on the cloud point of poloxamine 908. Four effective cloud point boosters (CPBs) from different structural classes were further tested on additional surfactants. RESULTS: A number of compounds can raise the cloud point of nonionic surfactants. These cloud point boosters are classified into two categories: nonionic and ionic. The nonionic CPBs include poly(ethylene glycols), propylene glycol, methanol, ethanol, isopropanol, and 2-hydroxypropyl-beta-cyclodextrin. They are effective at molar concentrations. The ionic CPBs include anionic and cationic surfactants, charged phospholipids, long chain fatty acids, and bile salts. They are effective at millimolar concentrations. CONCLUSIONS: The cloud point of nonionic surfactants used in liquid formulations can be modulated through the proper choice of excipient.


Asunto(s)
Excipientes/química , Tensoactivos/química , Alcoholes/química , Tampones (Química) , Carbohidratos/química , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Portadores de Fármacos/química , Etilenodiaminas/química , Ácidos Grasos/química , Ionóforos/química , Iones , Tamaño de la Partícula , Fosfolípidos/química , Polietilenglicoles/química , Solubilidad , Temperatura
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