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1.
J Reconstr Microsurg ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914111

RESUMEN

BACKGROUND: Fasciocutaneous free deltoid flaps are used to reconstruct hand, foot, and maxillofacial defects. Although anatomical studies of this flap pedicle have been performed on cadavers, there are no reports on the use of 320-detector row computed tomography angiography (CTA-320) to investigate the deltoid flap pedicle in living humans. This study aimed to investigate the arterial characteristics of the deltoid flap pedicle using the CTA-320 system in living humans. METHODS: Twenty-seven adult Vietnamese patients with 54 healthy deltoid regions underwent CTA-320 to investigate arterial blood supply before clinical free-flap transfer. Two- and three-dimensional reconstruction images of the arterial pedicle were visualized, and clinical reconstruction results were evaluated. RESULTS: The cutaneous vessel branches of the deltoid flap were separated from the posterior circumflex humeral artery (PCHA) and originated from the axillary (77.78%), subscapular (12.96%), and brachial (9.26%) arteries. The PCHA penetrated the quadrangular space in 90.74% of patients. The cutaneous arterial branch was present in the deltoid-triceps groove in 100% of patients. The average diameter and length of the PCHA were 3.38 ± 0.58 and 43.08 ± 6.60 mm, respectively. The average diameter and length of the flap cutaneous branch were 1.49 ± 0.28 and 44.57 ± 4.83 mm, respectively. The findings of CTA-320 were aligned with the intraoperative clinical findings well. All deltoid flaps were successfully free-transferred with good outcomes. CONCLUSION: The CTA-320 is a practical and effective method for investigating deltoid flap pedicles. It enables accurate flap design and harvesting of flaps, thereby enhancing the clinical success of free-flap transfer.

2.
Surg Radiol Anat ; 43(10): 1711-1719, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34226966

RESUMEN

PURPOSE: Using 320-detector row computed tomography angiography (320-CTA) to investigate the arterial supply for the toe flaps, namely the anatomical characteristics of the dorsalis pedis artery (DPA), the first dorsal metatarsal artery (FDMA), and the arteries of the first toe web space (AsFTWS). METHODS: This was a prospective study on CTA of 72 intact feet of 36 Vietnamese adults who had sequelae of thumb or metacarpal hand amputation, from June 2017 to December 2019, then preoperative CTA images were compared with surgical findings on 31 feet of 29 patients. RESULTS: 320-CTA was able to investigate the DPA, FDMA, and AsFTWS in 100% of cases. DPA was absent in 6.9% of cases. The average diameters at its origin and termination were 3.22 and 2.56 mm, respectively. For FDMA, the rates of Gilbert type I, II, and III were 52.8%, 18.1%, and 29.2%; the average diameters at its origin and termination were 1.98 and 1.67 mm, respectively. At the first toe web space, FDMA was dominant in 54.2% of cases; the first plantar metatarsal artery (FPMA) was dominant in 29.2% of cases; both arteries were equally dominant in 16.6%. The average diameter at the origin of the lateral plantar digital artery of the great toe was 1.48 mm, of the medial plantar digital artery of the second toe was 1.21 mm. Preoperative CTA images resembled the surgical findings in all cases. The survival rate of toe flaps was 100%. CONCLUSION: The 320-CTA provided proper preoperative images in two and three dimensions, and helped surgeons to establish a preoperative surgical plan, thus increasing the success rate of toe transfer surgery.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Colgajos Quirúrgicos/irrigación sanguínea , Dedos del Pie/anatomía & histología , Dedos del Pie/irrigación sanguínea , Adulto , Amputación Quirúrgica , Femenino , Mano/cirugía , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Pulgar/cirugía , Dedos del Pie/diagnóstico por imagen , Vietnam , Adulto Joven
3.
BMC Infect Dis ; 19(1): 737, 2019 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-31438878

RESUMEN

BACKGROUND: Brainstem encephalitis is a serious complication of hand foot and mouth disease (HFMD) in children. Autonomic nervous system (ANS) dysregulation and hypertension may occur, sometimes progressing to cardiopulmonary failure and death. Vietnamese national guidelines recommend use of milrinone if ANS dysregulation with Stage 2 hypertension develops. We wished to investigate whether magnesium sulfate (MgSO4) improved outcomes in children with HFMD if used earlier in the evolution of the ANS dysregulation (Stage 1 hypertension). METHODS: During a regional epidemic we conducted a randomized, double-blind, placebo-controlled trial of MgSO4 in children with HFMD, ANS dysregulation and Stage 1 hypertension, at the Hospital for Tropical Diseases in Ho Chi Minh city. Study participants received an infusion of MgSO4 or matched placebo for 72 h. We also reviewed data from non-trial HFMD patients in whom milrinone failed to control hypertension, some of whom received MgSO4 as second line therapy. The primary outcome for both analyses was a composite of disease progression within 72 h - addition of milrinone (trial participants only), need for ventilation, shock, or death. RESULTS: Between June 2014 and September 2016, 14 and 12 participants received MgSO4 or placebo respectively, before the trial was stopped due to futility. Among 45 non-trial cases with poorly controlled hypertension despite high-dose milrinone, 33 received MgSO4 while 12 did not. There were no statistically significant differences in the composite outcome between the MgSO4 and the placebo/control groups in either study (adjusted relative risk (95%CI) of [6/14 (43%) vs. 6/12 (50%)], 0.84 (0.37, 1.92), p = 0.682 in the trial and [1/33 (3%) vs. 2/12 (17%)], 0.16 (0.01, 1.79), p = 0.132 in the observational cohort). The incidence of adverse events was similar between the groups. Potentially toxic magnesium levels occurred very rarely with the infusion regime used. CONCLUSION: Although we could not demonstrate efficacy in these studies, there were no safety signals associated with use of 30-50 mg/kg/hr. MgSO4 in severe HFMD. Intermittent outbreaks of HFMD are likely to continue across the region, and an adequately powered trial is still needed to evaluate use of MgSO4 in controlling hypertension in severe HFMD, potentially involving a higher dose regimen. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01940250 (Registered 22 AUG 2013). Trial sponsor: University of Oxford.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/tratamiento farmacológico , Enfermedad de Boca, Mano y Pie/tratamiento farmacológico , Sulfato de Magnesio/uso terapéutico , Animales , Sistema Nervioso Autónomo/efectos de los fármacos , Sistema Nervioso Autónomo/fisiología , Enfermedades del Sistema Nervioso Autónomo/etiología , Niño , Preescolar , Estudios de Cohortes , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Enfermedad de Boca, Mano y Pie/complicaciones , Enfermedad de Boca, Mano y Pie/fisiopatología , Hemodinámica/efectos de los fármacos , Humanos , Lactante , Sulfato de Magnesio/efectos adversos , Masculino , Placebos
4.
J Infect Dis ; 207(9): 1442-50, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22807519

RESUMEN

BACKGROUND: Dengue is the most common arboviral infection of humans. There are currently no specific treatments for dengue. Balapiravir is a prodrug of a nucleoside analogue (called R1479) and an inhibitor of hepatitis C virus replication in vivo. METHODS: We conducted in vitro experiments to determine the potency of balapiravir against dengue viruses and then an exploratory, dose-escalating, randomized placebo-controlled trial in adult male patients with dengue with <48 hours of fever. RESULTS: The clinical and laboratory adverse event profile in patients receiving balapiravir at doses of 1500 mg (n = 10) or 3000 mg (n = 22) orally for 5 days was similar to that of patients receiving placebo (n = 32), indicating balapiravir was well tolerated. However, twice daily assessment of viremia and daily assessment of NS1 antigenemia indicated balapiravir did not measurably alter the kinetics of these virological markers, nor did it reduce the fever clearance time. The kinetics of plasma cytokine concentrations and the whole blood transcriptional profile were also not attenuated by balapiravir treatment. CONCLUSIONS: Although this trial, the first of its kind in dengue, does not support balapiravir as a candidate drug, it does establish a framework for antiviral treatment trials in dengue and provides the field with a clinically evaluated benchmark molecule. CLINICAL TRIALS REGISTRATION: NCT01096576.


Asunto(s)
Antivirales/administración & dosificación , Dengue/tratamiento farmacológico , Nucleósidos/administración & dosificación , Administración Oral , Adulto , Antígenos Virales/sangre , Antivirales/efectos adversos , Dengue/patología , Dengue/virología , Virus del Dengue/aislamiento & purificación , Método Doble Ciego , Fiebre/tratamiento farmacológico , Humanos , Masculino , Nucleósidos/efectos adversos , Placebos/administración & dosificación , Resultado del Tratamiento , Carga Viral , Viremia/tratamiento farmacológico , Adulto Joven
5.
Circulation ; 126(11 Suppl 1): S239-44, 2012 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-22965989

RESUMEN

BACKGROUND: No human physiological data exists on whether aspirin only is as effective as warfarin plus aspirin in preventing cerebral microembolization in the early postoperative period after bioprosthetic aortic valve replacement (bAVR). METHODS AND RESULTS: We prospectively enrolled 56 patients who had no other indication for oral anticoagulation, who underwent bAVR and received, in an open-label fashion, either daily warfarin (for INR 2.0-3.0) plus 81 mg of aspirin (n=28) or 325 mg of aspirin only (n=28). Cerebral microembolization was quantified at 4 hours (baseline) and at 1 month postoperatively, by recording 1-hour bilateral middle cerebral artery (MCA) microembolic signals (MES). Platelet-function analysis (PFA) of closure times (CT) on collagen was also used as a marker of platelet-dependent activation. Follow-up to 1 year was complete. Preoperative demographics and baseline platelet function were equivalent in both groups. There was no mortality, stroke, or transient ischemic attack at 1 year in either group. No significant differences were found in the proportion of patients with MES among those receiving warfarin plus aspirin versus aspirin only, at baseline (68% versus 82%, respectively; P=0.4) and at 1 month (46% versus 43%; P=1.0) after bAVR. The total MES and PFA were also equivalent between groups, at baseline and follow-up. CONCLUSIONS: Early after bAVR, the effects of these 2 antithrombotic regimens on cerebral microembolization and platelet function are equivalent. These data bring new mechanistic support to the premise that aspirin only may safely be used early after bAVR in patients who have no other indication for oral anticoagulation.


Asunto(s)
Anticoagulantes/uso terapéutico , Aspirina/uso terapéutico , Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Infarto de la Arteria Cerebral Media/prevención & control , Complicaciones Posoperatorias/prevención & control , Warfarina/uso terapéutico , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Estenosis de la Válvula Aórtica/cirugía , Aspirina/administración & dosificación , Aspirina/efectos adversos , Colágeno/farmacología , Puente de Arteria Coronaria/estadística & datos numéricos , Sinergismo Farmacológico , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Humanos , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/epidemiología , Infarto de la Arteria Cerebral Media/etiología , Masculino , Persona de Mediana Edad , Selectina-P/biosíntesis , Activación Plaquetaria/efectos de los fármacos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Ultrasonografía Doppler Transcraneal , Warfarina/administración & dosificación , Warfarina/efectos adversos
6.
Sci Data ; 10(1): 277, 2023 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-37173336

RESUMEN

Mammography, or breast X-ray imaging, is the most widely used imaging modality to detect cancer and other breast diseases. Recent studies have shown that deep learning-based computer-assisted detection and diagnosis (CADe/x) tools have been developed to support physicians and improve the accuracy of interpreting mammography. A number of large-scale mammography datasets from different populations with various associated annotations and clinical data have been introduced to study the potential of learning-based methods in the field of breast radiology. With the aim to develop more robust and more interpretable support systems in breast imaging, we introduce VinDr-Mammo, a Vietnamese dataset of digital mammography with breast-level assessment and extensive lesion-level annotations, enhancing the diversity of the publicly available mammography data. The dataset consists of 5,000 mammography exams, each of which has four standard views and is double read with disagreement (if any) being resolved by arbitration. The purpose of this dataset is to assess Breast Imaging Reporting and Data System (BI-RADS) and breast density at the individual breast level. In addition, the dataset also provides the category, location, and BI-RADS assessment of non-benign findings. We make VinDr-Mammo publicly available as a new imaging resource to promote advances in developing CADe/x tools for mammography interpretation.


Asunto(s)
Benchmarking , Enfermedades de la Mama , Humanos , Mama/diagnóstico por imagen , Computadores , Mamografía/métodos
7.
JMIR Form Res ; 7: e42895, 2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36668902

RESUMEN

BACKGROUND: Machine learning (ML) is a type of artificial intelligence strategy. Its algorithms are used on big data sets to see patterns, learn from their results, and perform tasks autonomously without being instructed on how to address problems. New diseases like COVID-19 provide important data for ML. Therefore, all relevant parameters should be explicitly quantified and modeled. OBJECTIVE: The purpose of this study was to determine (1) the overall preclinical characteristics, (2) the cumulative cutoff values and risk ratios (RRs), and (3) the factors associated with COVID-19 severity in unidimensional and multidimensional analyses involving 2173 SARS-CoV-2 patients. METHODS: The study population consisted of 2173 patients (1587 mild status [mild group] and asymptomatic patients, 377 moderate status patients [moderate group], and 209 severe status patients [severe group]). The status of the patients was recorded from September 2021 to March 2022. Two correlation tests, relative risk, and RR were used to eliminate unbalanced parameters and select the most remarkable parameters. The independent methods of hierarchical cluster analysis and k-means were used to classify parameters according to their r values. Finally, network analysis provided a 3-dimensional view of the results. RESULTS: COVID-19 severity was significantly correlated with age (mild-moderate group: RR 4.19, 95% CI 3.58-4.95; P<.001), scoring index of chest x-ray (mild-moderate group: RR 3.29, 95% CI 2.76-3.92; P<.001; moderate-severe group: RR 3.03, 95% CI 2.4023-3.8314; P<.001), percentage of neutrophils (mild-moderate group: RR 3.18, 95% CI 2.73-3.70; P<.001; moderate-severe group: RR 3.32, 95% CI 2.6480-4.1529; P<.001), quantity of neutrophils (moderate-severe group: RR 3.15, 95% CI 2.6153-3.8025; P<.001), albumin (moderate-severe group: RR 0.46, 95% CI 0.3650-0.5752; P<.001), C-reactive protein (mild-moderate group: RR 3.4, 95% CI 2.91-3.97; P<.001), and ratio of lymphocytes (moderate-severe group: RR 0.34, 95% CI 0.2743-0.4210; P<.001). Significant inversion of correlations among the severity groups is important. Alanine transaminase and leucocytes showed a significant negative correlation (r=-1; P<.001) in the mild group and a significant positive correlation in the moderate group (r=1; P<.001). Transferrin and anion Cl showed a significant positive correlation (r=1; P<.001) in the mild group and a significant negative correlation in the moderate group (r=-0.59; P<.001). The clustering and network analysis showed that in the mild-moderate group, the closest neighbors of COVID-19 severity were ferritin and age. C-reactive protein, scoring index of chest x-ray, albumin, and lactate dehydrogenase were the next closest neighbors of these 3 factors. In the moderate-severe group, the closest neighbors of COVID-19 severity were ferritin, fibrinogen, albumin, quantity of lymphocytes, scoring index of chest x-ray, white blood cell count, lactate dehydrogenase, and quantity of neutrophils. CONCLUSIONS: This multidimensional study in Vietnam showed possible correlations between several elements and COVID-19 severity to provide clinical reference markers for surveillance and diagnostic management.

8.
Pharmaceutics ; 15(5)2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37242765

RESUMEN

(1) Background: Magnetite (Fe3O4) nanoparticles have great potential for biomedical applications, including hyperthermia and magnetic resonance imaging. In this study, we aimed to identify the biological activity of nanoconjugates composed of superparamagnetic Fe3O4 nanoparticles coated with alginate and curcumin (Fe3O4/Cur@ALG) in cancer cells. (2) Methods: The nanoparticles were evaluated for the biocompatibility and toxicity on mice. The MRI enhancement and hyperthermia capacities of Fe3O4/Cur@ALG were determined in both in vitro and in vivo sarcoma models. (3) Results: The results show that the magnetite nanoparticles exhibit high biocompatibility and low toxicity in mice at Fe3O4 concentrations up to 120 mg/kg when administered via intravenous injection. The Fe3O4/Cur@ALG nanoparticles enhance the magnetic resonance imaging contrast in cell cultures and tumor-bearing Swiss mice. The autofluorescence of curcumin also allowed us to observe the penetration of the nanoparticles into sarcoma 180 cells. In particular, the nanoconjugates synergistically inhibit the growth of sarcoma 180 tumors via magnetic heating and the anticancer effects of curcumin, both in vitro and in vivo. (4) Conclusions: Our study reveals that Fe3O4/Cur@ALG has a high potential for medicinal applications and should be further developed for cancer diagnosis and treatment.

9.
J Clin Imaging Sci ; 12: 56, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36325494

RESUMEN

Tracheal bronchus (TB) is a very rare condition, which is often associated with some other pathologies. This study was designed to characterize the morphology of tracheal bronchus and associated pathologies in Vietnamese individuals using multidetector-row computed tomography (MDCT). From August 2016 to February 2021, 16, 64-, and 128-detector-row computed tomography scanners were used to perform chest scans of 3663 patients, of whom 32 had tracheal bronchus and associated pathologies. The prevalence of tracheal bronchus was 0.9%, of which 0.6% were male and 0.3% were female. We found that one patient had bilateral tracheal bronchus (3.1%) and 31 patients (96.9%) had right-sided tracheal bronchus. Most patients (75.1%) had type II tracheal bronchus, whereas 15.6% and 6.2% had type III and type I tracheal bronchus, respectively. The average distance from the tracheal bronchus to the carina was 6.6 ± 6.4 mm. The average diameter of the tracheal bronchus was 4.4 ± 2.2 mm; the group with 2-4-mm tracheal bronchus accounted for the highest proportion (46.9%). Associated pathologies included congenital heart diseases (i.e., valvular heart disease, tetralogy of Fallot, cyanotic congenital heart disease-APSO, and aortic coarctation) (43.7%), stenosis of the bilateral pulmonary arteries (15.6%), absent left pulmonary artery (6.2%), stenosis of the right pulmonary artery (3.1%), anomalous pulmonary venous connection (3.1%), stenosis of the trachea (3.1%), stenosis of the left main bronchus (3.1%), bronchogenic cyst (3.1%), and bronchial atresia (3.1%), and the remaining 12.5% had no abnormalities. tracheal bronchus is a very rare abnormality among Vietnamese and is often accompanied by other pathologies. MDCT with a high spatial resolution and a good tissue contrast, along with contrast agent and appropriate scanning protocols, is efficient in detecting tracheal bronchus and associated pathologies.

10.
Radiol Case Rep ; 17(9): 3349-3354, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35865366

RESUMEN

Primary cardiac angiosarcoma is an extremely rare, high-grade malignancy. Here, we describe the case of a 44-year-old male patient with a heart tumor in the left atrium wall, which caused a large amount of pericardial effusion that invaded the surrounding area and is visible on transthoracic echocardiography, computed tomography, and magnetic resonance imaging. The postoperative histopathological results confirmed this case as a primary cardiac epithelioid angiosarcoma.

11.
Radiol Case Rep ; 17(3): 856-862, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35035650

RESUMEN

A cardiac cavernous hemangioma is a rare, primary, benign tumor that is usually diagnosed in young or middle-aged patients. In this article, we report the case of a 71-year-old male patient whose doctors incidentally discovered a heart tumor on his transthoracic echocardiography. Triple-phase computed tomography (CT) (pre-contrast, arterial and portal venous) missed the lesion, and magnetic resonance imaging (MRI) revealed a small, oval tumor attached to the wall of the right ventricle. The tumor was successfully removed surgically, and the patient recovered after 2 weeks. A histopathological examination resulted in the diagnosis of a benign cavernous hemangioma.

12.
Sci Data ; 9(1): 429, 2022 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-35858929

RESUMEN

Most of the existing chest X-ray datasets include labels from a list of findings without specifying their locations on the radiographs. This limits the development of machine learning algorithms for the detection and localization of chest abnormalities. In this work, we describe a dataset of more than 100,000 chest X-ray scans that were retrospectively collected from two major hospitals in Vietnam. Out of this raw data, we release 18,000 images that were manually annotated by a total of 17 experienced radiologists with 22 local labels of rectangles surrounding abnormalities and 6 global labels of suspected diseases. The released dataset is divided into a training set of 15,000 and a test set of 3,000. Each scan in the training set was independently labeled by 3 radiologists, while each scan in the test set was labeled by the consensus of 5 radiologists. We designed and built a labeling platform for DICOM images to facilitate these annotation procedures. All images are made publicly available in DICOM format along with the labels of both the training set and the test set.


Asunto(s)
Algoritmos , Radiografías Pulmonares Masivas , Humanos , Radiografía , Radiólogos , Estudios Retrospectivos
13.
Circulation ; 122(3): 236-44, 2010 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-20606116

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia observed in otherwise healthy individuals. Most lone AF cases are nonfamilial, leading to the assumption that a primary genetic origin is unlikely. In this study, we provide data supporting a novel paradigm that atrial tissue-specific genetic defects may be associated with sporadic cases of lone AF. METHODS AND RESULTS: We sequenced the entire coding region of the connexin 43 (Cx43) gene (GJA1) from atrial tissue and lymphocytes of 10 unrelated subjects with nonfamilial, lone AF who had undergone surgical pulmonary vein isolation. In the atrial tissue of 1 patient, we identified a novel frameshift mutation caused by a single nucleotide deletion (c.932delC) that predicted 36 aberrant amino acids followed by a premature stop codon, leading to truncation of the C-terminal domain of Cx43. The mutation was absent from the lymphocyte DNA of the patient, indicating genetic mosaicism. Protein trafficking studies demonstrated intracellular retention of the mutant protein and a dominant-negative effect on gap junction formation of both wild-type Cx43 and Cx40. Electrophysiological studies revealed no electrical coupling of cells expressing the mutant protein alone and significant reductions in coupling when coexpressed with wild-type connexins. CONCLUSIONS: This study reports atrial tissue genetic mosaicism of a novel loss-of-function Cx43 mutation associated with lone AF. These findings implicate somatic genetic defects of Cx43 as a potential cause of AF and support the paradigm that sporadic, nonfamilial cases of lone AF may arise from genetic mosaicism that creates heterogeneous coupling patterns, predisposing the tissue to reentrant arrhythmias.


Asunto(s)
Fibrilación Atrial/genética , Conexina 43/genética , Uniones Comunicantes/fisiología , Eliminación de Gen , Mosaicismo , Animales , Apéndice Atrial/fisiología , Fibrilación Atrial/metabolismo , Fibrilación Atrial/fisiopatología , Conexina 43/metabolismo , Atrios Cardíacos , Humanos , Inmunohistoquímica , Linfocitos/fisiología , Oocitos/fisiología , Técnicas de Placa-Clamp , Fenotipo , Transporte de Proteínas/fisiología , Xenopus
14.
Biochem Biophys Res Commun ; 380(1): 132-7, 2009 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-19167345

RESUMEN

Genetic mutations of the cardiac sodium channel (SCN5A) specific only to the phenotype of atrial fibrillation have recently been described. However, data on the biophysical properties of SCN5A variants associated with atrial fibrillation are scarce. In a mother and son with lone atrial fibrillation, we identified a novel SCN5A coding variant, K1493R, which altered a highly conserved residue in the DIII-IV linker and was located six amino acids downstream from the fast inactivation motif of sodium channels. Biophysical studies of K1493R in tsA201 cells demonstrated a significant positive shift in voltage-dependence of inactivation and a large ramp current near resting membrane potential, indicating a gain-of-function. Enhanced cellular excitability was observed in transfected HL-1 atrial cardiomyocytes, including spontaneous action potential depolarizations and a lower threshold for action potential firing. These novel biophysical observations provide molecular evidence linking cellular "hyperexcitability" as a mechanism inducing vulnerability to this common arrhythmia.


Asunto(s)
Potenciales de Acción/genética , Fibrilación Atrial/genética , Fibrilación Atrial/fisiopatología , Proteínas Musculares/genética , Canales de Sodio/genética , Secuencia de Aminoácidos , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Mutación , Canal de Sodio Activado por Voltaje NAV1.5
15.
J Thorac Cardiovasc Surg ; 154(3): 927-935, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28826154

RESUMEN

OBJECTIVE: To establish the risk factors and impact of reexploration for bleeding in a large modern cardiac surgical cohort. METHODS: At a tertiary referral center, baseline, index procedural, reexploration, outcome, and readmission characteristics of 16,793 consecutive adult cardiac surgery patients were prospectively entered into dedicated clinical databases. Correlates of reexploration for bleeding, as well as its association with outcomes and readmission, were examined with multivariable regression models. RESULTS: The mean patient age was 65.9 ± 12.1 years, and 11,991 patients (71.4%) patients were male. Perioperative mortality was 2.8% (458 of 16,132) in those who did not undergo reexploration for bleeding and 12.0% (81 of 661) in those who underwent reexploration for bleeding, corresponding to an odds ratio of 3.4 ± 0.5 (P <.001) over other predictors of mortality, including Euroscore II. Mortality was highest in patients who underwent reexploration after the day of index surgery (odds ratio, 6.4 ± 1.1). Hospital stay was longer in patients who underwent reexploration for bleeding (median, 12 days, vs 7 days in patients who did not undergo reexploration; P <.001), to an extent beyond any other correlate. Reexploration for bleeding also was independently associated with new-onset postoperative atrial fibrillation, renal insufficiency, intensive care unit readmission, and wound infection. Risk factors for reexploration for bleeding were tricuspid valve repair, on-pump versus off-pump coronary artery bypass grafting, emergency status, cardiopulmonary bypass (CPB) duration, low body surface area, and lowest CPB hematocrit of <24%. CONCLUSIONS: Reexploration for bleeding is a lethal and morbid complication of cardiac surgery, with a detrimental effect that surpasses that of any other known potentially modifiable risk factor. All efforts should be made to minimize the incidence and burden of reexploration for bleeding, including further research on transfusion management during CPB.


Asunto(s)
Procedimientos Quirúrgicos Cardiovasculares , Hemorragia Posoperatoria/cirugía , Reoperación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/epidemiología , Femenino , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Ontario/epidemiología , Readmisión del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Insuficiencia Renal/epidemiología , Infección de Heridas/epidemiología , Adulto Joven
16.
Pain ; 95(1-2): 125-31, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11790475

RESUMEN

Pain-related somatosensory-evoked potential following CO(2) laser stimulation (laser-evoked potential (LEP)) is now used not only for research objectives, but also for clinical applications. Estimating the conduction velocity (CV) of the spinothalamic tract (STT) by analyzing LEP following activation of Adelta-fibers (Adelta-CVSTT) by CO(2) laser stimulation has been performed previously, but estimating the CV of STT following activation of C-fibers (C-CVSTT) has not. This is the first report to estimate the C-CVSTT in humans; by using the novel method of CO(2) laser stimulation applied to tiny skin areas. The calculation method was based on that of Kakigi and Shibasaki (Electroenceph clin Neurophysiol 80 (1991) 39) who measured Adelta-CVSTT by conventional CO(2) laser stimulation. The C-CVSTT ranged between 1.4 and 4.0 m/s, and its mean+/-SD was 2.9+/-0.8 m/s. This C-CVSTT was significantly slower than the Adelta-CVSTT, which ranged approximately from 10 to 21 m/s. The nociceptive signal of the C-fibers in STT is probably conveyed by unmyelinated axons of projection neurons to reach the thalamus. Our findings provide the first physiological evidence of the signals ascending through unmyelinated axons in the spinal cord in humans. In addition, estimating C-CVSTT and Adelta-CVSTT combined with conventional methods to measure the CV of the posterior column using electrical stimulation should be useful and have important clinical applications, particularly in patients with spinal cord lesions showing various kinds of sensory disturbances.


Asunto(s)
Dióxido de Carbono , Rayos Láser , Fibras Nerviosas/fisiología , Conducción Nerviosa/fisiología , Tractos Espinotalámicos/fisiología , Adulto , Potenciales Evocados/fisiología , Femenino , Humanos , Masculino , Estadísticas no Paramétricas
17.
Neurosci Lett ; 347(1): 41-4, 2003 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-12865137

RESUMEN

To investigate whether humans achieve a high sensitivity to coherent motion by excluding the response to incoherent motion, we measured the magnetoencephalographic response to the motion of randomly located dots one half of which moved coherently while the other half moved incoherently. The response was related to the faster motion of either coherent or incoherent motion though the observers saw both. All the estimated response sources were within the extrastriate area. The results indicate that incoherent motion is represented in the neural activity of the human extrastriate area even when the coherent motion is perceived at the same time. The fact that the neural activity for the slower coherent motion is not represented in the magnetic response suggests the existence of interaction between the neural activities for the two motions.


Asunto(s)
Corteza Cerebral/fisiología , Percepción de Movimiento/fisiología , Adulto , Femenino , Humanos , Magnetoencefalografía , Masculino , Tiempo de Reacción , Percepción Visual/fisiología
18.
Eur J Cardiothorac Surg ; 44(6): 1051-5; discussion 1055-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23530025

RESUMEN

OBJECTIVES: The impact of anaemia on patients undergoing aortic valve surgery has not been well studied. We sought to evaluate the effect of anaemia on early outcomes following aortic valve replacement (AVR). METHODS: All patients undergoing non-emergent aortic valve surgery (n = 2698) with or without other concomitant procedures between 1997 and 2010 were included. Preoperative anaemia was defined as per World Health Organization guidelines as haemoglobin (Hb) < 130 g/l in men and Hb < 120 g/l in women. Multivariable analyses were used to determine the association between preoperative anaemia and postoperative outcomes. RESULTS: The prevalence of preoperative anaemia was 32.2%. Patients with anaemia were older (71 ± 12 vs 66 ± 13 years, P < 0.001), more likely to have urgent surgery, recent MI, higher creatinine level and impaired preoperative left ventricular function. Overall unadjusted mortality was 2.8% in non-anaemic patients vs 8% in anaemic patients. Anaemic patients were more likely to require renal replacement therapy (11 vs 3%, P < 0.0001) and prolonged ventilation (24 vs 10%, P < 0.0001). Following multivariable adjustment, lower preoperative Hb was an independent predictor of mortality (odds ratio 1.19, 95% CI: 1.04-1.34, P = 0.007) and composite morbidity (odds ratio 1.36, 95% CI: 1.05-1.77, P = 0.02) after AVR. Mortality and composite morbidity were significantly higher with lower levels of preoperative Hb. CONCLUSIONS: Preoperative anaemia is a common finding in patients undergoing aortic valve surgery and is an important and potentially modifiable risk factor for postoperative morbidity and mortality.


Asunto(s)
Anemia/fisiopatología , Válvula Aórtica/cirugía , Enfermedades de las Válvulas Cardíacas/sangre , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Anemia/sangre , Femenino , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Hemoglobinas/metabolismo , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Morbilidad , Periodo Preoperatorio , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
19.
Curr Treat Options Cardiovasc Med ; 7(1): 47-54, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15913503

RESUMEN

The mainstay of heart failure therapy is aggressive medical management with consideration of resynchronization therapy and automatic implantable cardioverter-defibrillator. This is best done with the support of a multidisciplinary team. Transplantation, when possible, remains the therapy of choice for patients who are refractory to medical therapy. Other options short of left ventricular assist device (LVAD) that should be considered include revascularization, mitral valve repair, and left ventricular remodeling procedures. LVAD therapy as a bridge to transplantation should be considered in patients with heart failure who are clinically deteriorating while on the transplant waiting list. This should be initiated prior to the onset of irreversible end-organ damage. In nontransplant candidates, an LVAD can be considered as an alternative to transplantation (destination therapy). However, cost and the availability of expertise continue to limit this therapy to quaternary care and research institutions.

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