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1.
J Phys Chem A ; 124(2): 283-287, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31860315

RESUMEN

Lithium hydride (LiH) is a unique, ionic compound with applications in a variety of industries. Unfortunately, LiH is very reactive toward H2O even at ppm levels, forming oxide (Li2O) and hydroxide (LiOH) corrosion layers while outgassing H2. An effective means to eliminate unwanted outgassing is vacuum-heating to convert LiOH into Li2O, although subsequent re-exposure to moisture during transport/handling reconverts some Li2O back to LiOH. A corrosion growth model for previously vacuum-baked LiH is necessary for long-term prediction of the hydrolysis of LiH. In this work, a para-linear hydroxide corrosion growth model is proposed for the reaction of previously vacuum-baked LiH samples with moisture. This model, composed of two competing diffusion reaction fronts at the LiOH/Li2O and Li2O/LiH interfaces, is validated experimentally by subjecting a previously vacuum-baked polycrystalline LiH sample to 35 ppm of H2O at room temperature while monitoring the corrosion growth as a function of time with diffuse-reflectance infrared Fourier transform (DRIFT) spectroscopy. The para-linear growth model for the hydrolysis of previously vacuum-baked LiH proposed in this report can also serve as a template for the hydrolysis of other hygroscopic oxides grown on metal or metal hydride substrates.

2.
J Phys Chem A ; 124(41): 8390-8397, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32966071

RESUMEN

The hydrogenation of 1,4-diphenylbutadiyne (DPB) blended with carbon-supported Pd (DPB-Pd/C) in the form of pellets was investigated by isothermal-isobaric experiments at 1333 Pa of H2 and in the temperature range of 291-315 K. The extracted kinetics were then used in conjunction with a complementary constant rate of H2 input experimentation to model the performance of a DPB-catalysis/support system as a function of temperature and H2 partial pressure. First-principles density functional theory (DFT) calculations were also performed to shed light on the molecular level energetics of DPB and its intermediate states. A seemingly puzzling formation of alternate positive activation energy barrier (higher reaction rate with higher temperature) and negative activation energy barrier (higher reaction rate with lower temperature) zones during the hydrogenation process was discovered. However, this observed phenomenon can be logically explained in terms of the associated phase changes and H2 transport in the material. This work provides a good illustration of a rarely encountered chemical process with a negative activation energy barrier.

3.
J Chem Phys ; 147(19): 194701, 2017 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-29166097

RESUMEN

Measurements of equilibrium vapor pressures by effusion thermogravimetry and melting points by differential scanning calorimetry reveal that the melting temperature and equilibrium vapor pressures of 1,4-bis(phenylethynyl)benzene (DEB) do not vary monotonically with the hydrogenation extent. Contrary to intuition which suggests increasing volatility with hydrogenation, results indicate decreasing volatility for the first two hydrogenation steps before a non-monotonic upward trend, in which trans-isomers are less volatile. Insights on structural packing and functional groups were obtained from x-ray diffraction and infrared studies to shed light on the observed variation in the volatility of DEB with hydrogenation. Density functional theory calculations were performed to obtain molecular level information and to establish the thermodynamics of DEB hydrogenation reactions. A major factor influencing the observed melting points and volatility of the hydrogenated intermediate species is identified as the local attractive or repulsive carbon-hydrogen (CH) dipole interactions among the getter molecules in their respective crystal structures. Such collective CH dipole interactions can be used to predict the trends in the volatilities of catalytic hydrogenation processes.

4.
Nat Chem ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684816

RESUMEN

The importance of constructing Csp2-Csp3 bonds has motivated the development of electrochemical, photochemical and thermal activation methods to reductively couple abundant aryl and alkyl electrophiles. However, these methodologies are limited to couplings of very specific substrate classes and require specialized sets of catalysts and reaction set-ups. Here we show a consolidation of these myriad strategies into a single set of conditions that enable reliable alkyl-aryl couplings, including those that were previously unknown. These reactions rely on the discovery of unusually persistent organonickel complexes that serve as stoichiometric platforms for C(sp2)-C(sp3) coupling. Aryl, heteroaryl or vinyl complexes of Ni can be inexpensively prepared on a multigram scale by mild electroreduction from the corresponding C(sp2) electrophile. Organonickel complexes can be isolated and stored or telescoped directly to reliably diversify drug-like molecules. Finally, the procedure was miniaturized to micromole scales by integrating soluble battery chemistries as redox initiators, enabling a high-throughput exploration of substrate diversity.

5.
Int J Surg Case Rep ; 114: 109159, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38109800

RESUMEN

INTRODUCTION: Pulmonary artery thrombosis presents a rare and formidable challenge, especially in individuals with untreated complex congenital heart diseases and concurrent valvular abnormalities. PRESENTATION OF CASE: This case details a distinctive instance of pulmonary artery thrombosis in a patient with untreated congenital atrial septal defect, severe pulmonary hypertension, pulmonary aneurysm, valvular heart disease, and triple-positive antiphospholipid antibodies. Collaborative decision-making by a heart team guided the diagnostic and therapeutic processes, resulting in surgical interventions encompassing pulmonary thrombectomy, mitral and tricuspid regurgitation repair, and atrial septal defect closure. DISCUSSION: The case underscores the nuanced management of pulmonary artery thrombosis within the realm of congenital heart disease, highlighting the imperative role of a multidisciplinary approach in achieving accurate diagnoses and timely interventions. The multifaceted treatment strategy implemented further accentuates the need for continual monitoring and personalized interventions in intricate clinical scenarios. CONCLUSION: In conclusion, this case emphasizes the complexity of addressing pulmonary artery thrombosis in the context of congenital heart disease. The collaborative efforts of a multidisciplinary team proved pivotal in navigating diagnostic uncertainties and formulating a tailored treatment plan. Ongoing monitoring and personalized strategies remain crucial for optimizing outcomes in such intricate cases.

6.
Sci Rep ; 13(1): 14892, 2023 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-37689765

RESUMEN

Despite careful staging, the accuracy for preoperative detection of small distant metastases remains poor, creating a clinical need for enhanced operative staging to detect occult peritoneal metastases. This study evaluates a polarization-enhanced laparoscopy (PEL) prototype and assesses its potential for label-free contrast enhancement of peritoneal metastases. This is a first-in-human feasibility study, including 10 adult patients who underwent standard staging laparoscopy (SSL) for gastrointestinal malignancy along with PEL. Image frames of all detectable peritoneal lesions underwent analysis. Using Monte Carlo simulations, contrast enhancement based on the color dependence of PEL (mPEL) was assessed. The prototype performed safely, yet with limitations in illumination, fogging of the distal window, and image co-registration. Sixty-five lesions (56 presumed benign and 9 presumed malignant) from 3 patients represented the study sample. While most lesions were visible under human examination of both SSL and PEL videos, more lesions were apparent using SSL. However, this was likely due to reduced illumination under PEL. When controlling for such effects through direct comparisons of integrated (WLL) vs differential (PEL) polarization laparoscopy images, we found that PEL imaging yielded an over twofold Weber contrast enhancement over WLL. Further, enhancements in the discrimination between malignant and benign lesions were achieved by exploiting the PEL color contrast to enhance sensitivity to tissue scattering, influenced primarily by collagen. In conclusion, PEL appears safe and easy to integrate into the operating room. When controlling for the degree of illumination, image analysis suggested a potential for mPEL to provide improved visualization of metastases.


Asunto(s)
Laparoscopía , Enfermedades Peritoneales , Neoplasias Peritoneales , Adulto , Humanos , Neoplasias Peritoneales/diagnóstico por imagen , Neoplasias Peritoneales/cirugía , Peritoneo , Refracción Ocular
7.
ACS Catal ; 13(14): 9336-9345, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-38188282

RESUMEN

An electrochemical, nickel-catalyzed reductive coupling of alkylpyridinium salts and aryl halides is reported. High-throughput experimentation (HTE) was employed for rapid reaction optimization and evaluation of a broad scope of pharmaceutically relevant structurally diverse aryl halides, including complex drug-like substrates. In addition, the transformation is compatible with both primary and secondary alkylpyridinium salts with distinct conditions. Mechanistic insights were critical to enhance the efficiency of coupling using secondary alkylpyridinium salts. Systematic comparisons of the electrochemical and non-electrochemical methods revealed the complementary scope and efficiency of the two approaches.

8.
Res Sq ; 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37886476

RESUMEN

Hemophilia-A (HA) is caused by heterogeneous loss-of-function factor (F)VIII gene (F8)-mutations and deficiencies in plasma-FVIII-activity that impair intrinsic-pathway-mediated coagulation-amplification. The standard-of-care for severe-HA-patients is regular infusions of therapeutic-FVIII-proteins (tFVIIIs) but ~30% develop neutralizing-tFVIII-antibodies called "FVIII-inhibitors (FEIs)" and become refractory. We used the PATH study and ImmunoChip to scan immune-mediated-disease (IMD)-genes for novel and/or replicated genomic-sequence-variations associated with baseline-FEI-status while accounting for non-independence of data due to genetic-relatedness and F8-mutational-heterogeneity. The baseline-FEI-status of 450 North American PATH subjects-206 with black-African-ancestry and 244 with white-European-ancestry-was the dependent variable. The F8-mutation-data and a genetic-relatedness matrix were incorporated into a binary linear-mixed model of genetic association with baseline-FEI-status. We adopted a gene-centric-association-strategy to scan, as candidates, pleiotropic-IMD-genes implicated in the development of either ³2 autoimmune-/autoinflammatory-disorders (AADs) or ³1 AAD and FEIs. Baseline-FEI-status was significantly associated with SNPs assigned to NOS2A (rs117382854; p=3.2E-6) and B3GNT2 (rs10176009; p=5.1E-6), which have functions in anti-microbial-/-tumoral-immunity. Among IMD-genes implicated in FEI-risk previously, we identified strong associations with CTLA4 assigned SNPs (p=2.2E-5). The F8-mutation-effect underlies ~15% of the total heritability for baseline-FEI-status. Additive genetic heritability and SNPs in IMD-genes account for >50% of the patient-specific variability in baseline-FEI-status. Race is a significant determinant independent of F8-mutation-effects and non-F8-genetics.

9.
J Phys Chem A ; 116(22): 5312-6, 2012 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-22591128

RESUMEN

The rate of water desorption from PBX-9502, a formulation containing 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), is measured using temperature-programmed desorption and modeled using conventional kinetic modeling methods. The results of these studies show two stages of moisture release. At lower temperatures, the release is likely assisted by thermal expansion of the TATB and melting of the Kel-F binder. At higher temperatures, a considerable amount of water is released and is attributed to sublimation of the TATB, which exposes new surfaces for water desorption.

10.
Viruses ; 14(7)2022 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-35891446

RESUMEN

Allosteric HIV-1 integrase (IN) inhibitors, or ALLINIs, are a new class of antiviral agents that bind at the dimer interface of the IN, away from the enzymatic catalytic site and block viral replication by triggering an aberrant multimerization of the viral enzyme. To further our understanding of the important binding features of multi-substituted quinoline-based ALLINIs, we have examined the IN multimerization and antiviral properties of substitution patterns at the 6 or 8 position. We found that the binding properties of these ALLINIs are negatively impacted by the presence of bulky substitutions at these positions. In addition, we have observed that the addition of bromine at either the 6 (6-bromo) or 8 (8-bromo) position conferred better antiviral properties. Finally, we found a significant loss of potency with the 6-bromo when tested with the ALLINI-resistant IN A128T mutant virus, while the 8-bromo analog retained full effectiveness.


Asunto(s)
Inhibidores de Integrasa VIH , Integrasa de VIH , VIH-1 , Quinolinas , Regulación Alostérica , Antivirales/farmacología , Integrasa de VIH/metabolismo , Inhibidores de Integrasa VIH/química , Inhibidores de Integrasa VIH/farmacología , VIH-1/metabolismo , Quinolinas/farmacología , Replicación Viral
11.
Front Oncol ; 12: 888927, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36091142

RESUMEN

Introduction: Invasive Candida infection, or candidiasis, especially in gastrointestinal tract (GIT) is an infrequent but aggressive disease caused by Candida species. Candidiasis of gastrojejunostomosis after extensive gastrointestinal surgery may cause serious complications such as perforative peritonitis and anastomotic stenosis, which requires surgical interventions. Case presentation: Our two patients had undergone pancreaticoduodenectomy (PD), respectively, due to pancreatic ductal adenocarcinoma and intraductal papillary mucinous neoplasms of the pancreatic head. Both the patients were malnutritioned and debilitated before the surgery, and they required reoperation for postoperative Candidiasis-relevant complication.In the first case, the patient was readmitted to the hospital with symptoms of perforative peritonitis, for which he underwent surgery and had Candida found in both gastrojejunostomosis ulcer and peritoneal fluid. In our second case, the patient was admitted to the hospital twice after the first operation and diagnosed with Candida-induced gastrojejunostomosis stenosis by esophagogastroduodenoscopy (EGD) and endoscopic biopsy. Fluconazole was indicated for a 2-week regimen. Blood sample withdrawn afterward showed no evidence of fungal agents, and the anastomotic stenosis responded well to treatment. However, after 3 weeks, he came back with cachexia and symptoms of gastrojejunostomotic stenosis. EGD showed no image of fungal agents but anastomotic stenosis due to chronic inflammatory process. The patient was then reoperated to redo his gastrojejunostomosis. Conclusion: Candidiasis of gastrojejunostomosis after extensive gastrointestinal surgery such as PD is a very aggressive condition that may cause perforative peritonitis and anastomotic stenosis. However, there have been no publications on this disorder, and the strategic treatment remains unknown. We hereby present a report of two cases with postoperative gastrojejunostomosis candidiasis presenting with non-specific but aggressive and early clinical symptoms.

12.
RSC Adv ; 11(45): 28347-28351, 2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-35480780

RESUMEN

3-Aryl-1-phosphinoimidazo[1,5-a]pyridine ligands were synthesized from 2-aminomethylpyridine as the initial substrate via two complementary routes. The first synthetic pathway underwent the coupling of 2-aminomethylpyridine with substituted benzoyl chlorides, followed by cyclization, iodination and palladium-catalyzed cross-coupling phosphination reactions sequence to give our phosphorus ligands. In the second route, 2-aminomethylpyridine was cyclized with aryl aldehydes, followed by the iodination and palladium-catalyzed cross-coupling phosphination reactions to yield our phosphorus ligands. The 3-aryl-1-phosphinoimidazo[1,5-a]pyridine ligands were evaluated in palladium-catalyzed sterically-hindered biaryl and heterobiaryl Suzuki-Miyaura cross-coupling reactions.

13.
J Air Waste Manag Assoc ; 70(9): 932-943, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32579438

RESUMEN

Compressed Natural Gas (CNG) has been applied worldwide for in-used engines, especially CNG engines that are converted from the conventional engines. However, it encounters the problem related to the low power and high fuel consumption of the conventional engine fueled by CNG. This paper presents an experimental study on performance enhancement of a CNG engine converted from the spark-ignition engine by the implementation of fuel additive Maz 100. In experimental work, a fuel additive supplying system was developed to impose a certain amount of fuel additive to the intake manifold of the test engine. The study results show that when using Maz 100, the brake power of the test engine improves approximately 6.75% on average at full load conditions. The brake specific fuel consumption (BSFC) reduces 6.49% on average at full load and 3.53% on average at partial load condition. In addition, besides the benefit of performance enhancement, exhaust emissions of the test engine in the case of operating with fuel additive have changed considerably. Particularly, the CO emission reduces 36.1% at full load and 18.4% on average at partial load conditions. The HC emission reduces 37.1% at full load and 35.0% on average at partial load conditions. The NOx emission increases slightly in low-speed regimes and reduces in high-speed regimes when the engine operates at the full opened throttle condition. At partial load condition and speed of 3000 rpm, the NOx emission reduces 22.6% on average. Implications: This paper presents a solution for performance enhancement and emission reduction of natural gas engine by using fuel additive. Performance and emission characteristics of the natural gas engine fueled with fuel additive have been assessed in the laboratory. The performance of the test engine improves remarkably. The brake power of the test engine improves approximately 6.75% on average at full load conditions when the engine operates with fuel additive. The brake specific fuel consumption reduces 3.53% on average at partial load condition. The emission of pollution has different trends. The CO and HC emission reduces at testing conditions. The NOx emission increases slightly in low-speed regimes and reduces in high-speed regimes when the engine operates at the full opened throttle condition. The implementation of fuel additive is a potential solution for power improvement and emission reduction of natural gas engine.


Asunto(s)
Contaminación del Aire/prevención & control , Conservación de los Recursos Energéticos , Gasolina , Gas Natural , Contaminantes Atmosféricos/análisis , Monóxido de Carbono/análisis , Óxidos de Nitrógeno/análisis
14.
ACS Appl Mater Interfaces ; 12(3): 3993-4001, 2020 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-31880909

RESUMEN

The hydrogen uptake kinetics of 1,4-bis(phenylethynyl)benzene, or DEB, mixed with palladium (Pd) on activated carbon in a rubber matrix coating on top of a porous silicone foam substrate are investigated. First, isothermal isobaric hydrogenation experiments were performed under different temperatures and H2 pressures to extract the uptake kinetics. The H2 uptake models based on the measured kinetic parameters were then employed to investigate/simulate the performance of the getter under dynamic application environments. The actual hydrogenation characteristics in this type of getter are multifaceted and involve actual H2 concentration in the getter matrix, micrometer-scale diffusion of atomic hydrogen away from Pd sites, precipitation of hydrogenated DEB crystals at the coating surfaces, and mobility of fresh DEB molecules. The kinetic analysis/modeling methodology described in this report can serve as a template for other gas-solid reactions as well. Besides possessing a good hydrogen capacity and excellent performance, this type of rubberized getter also offers some unique advantages over traditional solid getter: flexible structure and protection of the Pd catalyst from exposure to the environment.

15.
J Thromb Haemost ; 18(1): 201-216, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31556206

RESUMEN

BACKGROUND: Plasma-derived (pd) or recombinant (r) therapeutic factor VIII proteins (FVIIIs) are infused to arrest/prevent bleeding in patients with hemophilia A (PWHA). However, FVIIIs are neutralized if anti-FVIII-antibodies (inhibitors) develop. Accumulating evidence suggests that pdFVIIIs with von Willebrand factor (VWF) are less immunogenic than rFVIIIs and that distinct rFVIIIs are differentially immunogenic. Since inhibitor development is T-helper-cell-dependent, human leukocyte antigen (HLA)-class-II (HLAcII) molecules constitute an important early determinant. OBJECTIVES: Use dendritic cell (DC)-protein processing/presentation assays with mass-spectrometric and peptide-proteomic analyses to quantify the DP-bound, DQ-bound, and DR-bound FVIII-derived peptides in individual HLAcII repertoires and compare the immunogenic potential of six distinct FVIIIs based on their measured peptide counts. PATIENTS/METHODS: Monocyte-derived DCs from normal donors and/or PWHA were cultured with either: Mix-rFVIII, a VWF-free equimolar mixture of a full-length (FL)-rFVIII [Advate® (Takeda)] and four distinct B-domain-deleted (BDD)-rFVIIIs [Xyntha® (Pfizer), NovoEight® (Novo-Nordisk), Nuwiq® (Octapharma), and Afstyla® (CSL Behring GmBH)]; a pdFVIII + pdVWF [Beriate® (CSL Behring GmBH)]; Advate ± pdVWF; Afstyla ± pdVWF; and Xyntha + pdVWF. RESULTS: We showed that (i) Beriate had a significantly lower immunogenic potential than Advate ± pdVWF, Afstyla - pdVWF, and Mix-rFVIII; (ii) distinct FVIIIs differed significantly in their immunogenic potential in that, in addition to (i), Afstyla + pdVWF had a significantly lower immunogenic potential than Beriate, while the immunogenic potential of Beriate was not significantly different from that of Xyntha + pdVWF; and (iii) rFVIIIs with pdVWF had significantly lower immunogenic potentials than the same rFVIIIs without pdVWF. CONCLUSIONS: Our results provide HLAcII peptidomic level explanations for several important clinical observations/issues including the differential immunogenicity of distinct FVIIIs and the role of HLAcII genetics in inhibitor development.


Asunto(s)
Factor VIII , Hemofilia A , Células Dendríticas , Antígenos HLA , Hemofilia A/tratamiento farmacológico , Humanos , Proteómica
16.
J Vasc Access ; 20(1_suppl): 20-23, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30596466

RESUMEN

A well-functioning vascular access is a mainstay to perform an efficient hemodialysis procedure, which directly affects the quality of life in hemodialysis patients. We use three main types of access: native arteriovenous fistula, arteriovenous graft, and central venous catheter. Arteriovenous fistula remains the first and best choice for chronic hemodialysis. It is the best access for longevity, the lowest related complications, and for this reason, arteriovenous fistula use is strongly recommended by guidelines from different countries, including Vietnam. In practice, well-functioning arteriovenous fistula creation is not always simple. In this case, arteriovenous fistula creation with vein transposition or translocation is certainly useful. When native vein options have been exhausted, prosthetic can be used as the second option of maintenance hemodialysis access alternatives. Central venous catheters are very common and have become an important adjunct in maintaining patients on hemodialysis. In Bach Mai hospital, we certainly create about 1000 new arteriovenous fistulas every year (among these, about 84.98% new hemodialysis patients start hemodialysis without permanent accesses and depend on temporary central venous catheters) and successfully matured arteriovenous fistula rate is 92.6%. Among hemodialysis population in Bach Mai, 2.29% have arteriovenous grafts and 2.81% of patients still depend on cuffed tunneled catheters. The preferable locations for catheter insertions are the internal jugular and femoral veins. Proper vascular access maintenance requires integration of different professionals to create a vascular access team. Percutaneous transluminal angioplasty is not available. In our circumstance, we have achieved some advantages for hemodialysis patients but still a big gap to an advanced country.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/tendencias , Implantación de Prótesis Vascular/tendencias , Cateterismo Venoso Central/tendencias , Evaluación de Procesos y Resultados en Atención de Salud/tendencias , Pautas de la Práctica en Medicina/tendencias , Diálisis Renal/tendencias , Derivación Arteriovenosa Quirúrgica/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Cateterismo Venoso Central/efectos adversos , Humanos , Factores de Tiempo , Resultado del Tratamiento , Vietnam/epidemiología
17.
RSC Adv ; 9(31): 17778-17782, 2019 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-35520553

RESUMEN

3-Aryl-2-phosphinoimidazo[1,2-a]pyridine ligands were synthesized from 2-aminopyridine via two complementary routes. The first synthetic route involves the copper-catalyzed iodine-mediated cyclizations of 2-aminopyridine with arylacetylenes followed by palladium-catalyzed cross-coupling reactions with phosphines. The second synthetic route requires the preparation of 2,3-diiodoimidazo[1,2-a]pyridine or 2-iodo-3-bromoimidazo[1,2-a]pyridine from 2-aminopyridine followed by palladium-catalyzed Suzuki/phosphination or a phosphination/Suzuki cross-coupling reactions sequence, respectively. Preliminary model studies on the Suzuki synthesis of sterically-hindered biaryl and Buchwald-Hartwig amination compounds are presented with these ligands.

18.
Ann Med Surg (Lond) ; 48: 88-90, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31737266

RESUMEN

INTRODUCTION: Malignant hyperthermia (MH) is a rare autosomal dominant pharmacogenetic disorder which known associated with some genes such as CACNA1S and RYR1. Using whole exome analysis, we aimed to find out the genetic variant data in a malignant hyperthermia patient undergoing cardiac surgery. PRESENTATION OF CASE: Patient was 59 years old male with dull left chest pain, mild breathing difficulty, thrombosis in the left atrium, mitral valve stenosis that needed a surgery to remove the thrombus and replace the mitral valve. After 5-h operation of left mitral heart valve replacement using both intravenous and inhaled anaesthetics, the patient showed suddenly hyperthermia (39.5 °C), low blood pressure (90/50 mmHg), heavy sweating, 1 mm dilated pupils on both sides, positive light reflection. Whole exome analysis showed 96,286 of SNPs including 11,705 of synonymous variants, 11,388 of missense variants, 106 of stop gained, and 39 of stop lost. One variant of RYR1 gene was found as mutation point at c.7048G > A (p.Ala2350Thr) known related to MH. DISCUSSION: This was a rare case of MH during cardiac surgery reported in Vietnam that might related to mutation point at c.7048G > A (p.Ala2350Thr) of RYR1 gene. CONCLUSION: Patient carried a mutant of RYR1 gene could possibly lead to MH development post anaesthesia of cardiac surgery.

19.
Medicines (Basel) ; 4(1)2017 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-28930228

RESUMEN

Background: Plant extracts have been used in traditional medicine for the treatment of various maladies including neurological diseases. Several central nervous system receptors have been demonstrated to interact with plant extracts and components affecting the pharmacology and thereby potentially playing a role in human disease and treatment. For instance, extracts from Hypericum perforatum (St. John's wort) targeted several CNS receptors. Similarly, extracts from Piper nigrum, Stephania cambodica, and Styphnolobium japonicum exerted inhibition of agonist-induced activity of the human neurokinin-1 receptor. Methods: Different methods have been established for receptor binding and functional assays based on radioactive and fluorescence-labeled ligands in cell lines and primary cell cultures. Behavioral studies of the effect of plant extracts have been conducted in rodents. Plant extracts have further been subjected to mood and cognition studies in humans. Results: Mechanisms of action at molecular and cellular levels have been elucidated for medicinal plants in support of standardization of herbal products and identification of active extract compounds. In several studies, plant extracts demonstrated affinity to a number of CNS receptors in parallel indicating the complexity of this interaction. In vivo studies showed modifications of CNS receptor affinity and behavioral responses in animal models after treatment with medicinal herbs. Certain plant extracts demonstrated neuroprotection and enhanced cognitive performance, respectively, when evaluated in humans. Noteworthy, the penetration of plant extracts and their protective effect on the blood-brain-barrier are discussed. Conclusion: The affinity of plant extracts and their isolated compounds for CNS receptors indicates an important role for medicinal plants in the treatment of neurological disorders. Moreover, studies in animal and human models have confirmed a scientific basis for the application of medicinal herbs. However, additional investigations related to plant extracts and their isolated compounds, as well as their application in animal models and the conducting of clinical trials, are required.

20.
IEEE Trans Pattern Anal Mach Intell ; 39(11): 2270-2283, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-27959802

RESUMEN

This paper investigates a new annotation technique that reduces significantly the amount of time to annotate training data for gesture recognition. Conventionally, the annotations comprise the start and end times, and the corresponding labels of gestures in sensor recordings. In this work, we propose a one-time point annotation in which labelers do not have to select the start and end time carefully, but just mark a one-time point within the time a gesture is happening. The technique gives more freedom and reduces significantly the burden for labelers. To make the one-time point annotations applicable, we propose a novel BoundarySearch algorithm to find automatically the correct temporal boundaries of gestures by discovering data patterns around their given one-time point annotations. The corrected annotations are then used to train gesture models. We evaluate the method on three applications from wearable gesture recognition with various gesture classes (10-17 classes) recorded with different sensor modalities. The results show that training on the corrected annotations can achieve performances close to a fully supervised training on clean annotations (lower by just up to 5 percent F1-score on average). Furthermore, the BoundarySearch algorithm is also evaluated on the ChaLearn 2014 multi-modal gesture recognition challenge recorded with Kinect sensors from computer vision and achieves similar results.


Asunto(s)
Gestos , Procesamiento de Imagen Asistido por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Aprendizaje Automático Supervisado , Acelerometría , Algoritmos , Humanos , Grabación en Video , Dispositivos Electrónicos Vestibles
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