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1.
J Arthroplasty ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38614358

RESUMEN

BACKGROUND: In patients undergoing total joint arthroplasty, the use of dexamethasone (DEX) may cause perioperative blood glucose (BG) disorders, leading to complications even in patients who do not have diabetes. We aimed to evaluate the effects of different DEX doses on perioperative BG levels. METHODS: A total of 135 patients who do not have diabetes were randomized into three groups: preoperative intravenous (IV) injection of normal saline (Group A, the placebo group), preoperative IV injection of 10 mg DEX (Group B), and preoperative IV injection of 20 mg DEX (Group C). Postoperative fasting BG (FBG) levels were designated as the primary outcome, while postoperative postprandial BG (PBG) levels were assigned as the secondary outcome. The incidence of complications was recorded. We also investigated the risk factors for FBG ≥ 140 mg/dL and PBG ≥ 180 mg/dL. RESULTS: The FBG levels were higher in Groups B and C than in Group A on postoperative days (PODs) 0 and 1. The PBG levels were lower for Groups A and B compared to Group C on POD 1. No differences in FBG or PBG were detected beyond POD 1. Elevated preoperative glycosylated hemoglobin A1c levels increased the risk of FBG ≥ 140 mg/dL and PBG ≥ 180 mg/dL, respectively. However, preoperative IV injection of DEX was not associated with FBG ≥ 140 mg/dL or PBG ≥ 180 mg/dL. No differences were found in postoperative complications among the three groups. CONCLUSIONS: The preoperative IV administration of 10 or 20 mg DEX in patients who do not have diabetes showed transient effects on postoperative BG after total joint arthroplasty. The preoperative glycosylated hemoglobin A1c level threshold (regardless of the administration or dosage of DEX) that increased the risk for the occurrence of FBG ≥ 140 mg/dL and PBG ≥ 180 mg/dL was 5.75 and 5.85%, respectively.

2.
BMC Musculoskelet Disord ; 22(1): 761, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34488716

RESUMEN

BACKGROUND: Up to now in the surgical treatment of Kümmell's disease combined with thoracolumbar kyphosis, little research has focused on the evaluation of the imaging and clinical outcomes of restoring the normal alignment and sagittal balance of the spine. This study aimed to evaluate the short to mid-term radiographic and clinical outcomes in the treatment of Kümmell's disease with thoracolumbar kyphosis. METHODS: From February 2016 to May 2018, 30 cases of Kümmell's disease with thoracolumbar kyphosis were divided into group A and B according to whether the kyphosis was combined with neurological deficits. All of the cases underwent surgical treatment to regain the normal spinal alignment and sagittal balance. The radiographic outcomes and clinical outcomes of the cases were retrospectively evaluated. The sagittal imaging parameters including sagittal vertebral axis (SVA),thoracic kyphosis (TK),thoracolumbar kyphosis (TLK),lumbar lordosis (LL),pelvic incidence (PI),pelvic tilt (PT),and sacral slope (SS) before operation,immediately after operation,and the last follow-up of each case were measured and evaluated. The clinical results included the Oswestry Disability Index (ODI) and the Numerical Rating Scale (NRS) of the two groups. Statistical software SPSS21.0 was used to analyze the data. RESULTS: In group A: Mean SVA before operation was 75 mm and 26.7 mm at the final postoperative evaluation (P = 0.000); Mean TLK before operation was 39°, and 7.1° at the final postoperative evaluation (P = 0.000); Mean NRS before operation was 4.7, compared with 0.9 at the final postoperative evaluation (P = 0.000). In group B: Mean preoperative SVA was 62.5 mm and decreases to 30.7 mm at the final postoperative evaluation (P = 0.000); Mean TLK before operation was 33°, and 9.7° 2 years post-operation (P = 0.000); Mean NRS prior to surgery was 4.0, and 0.8 at the last follow-up evaluation (P = 0.000). The improvement of the NRS scores of groups A and B was related to the improvement of the cobb angle (P = 0.020); (P = 0.009) respectively. CONCLUSION: In the treatment of Kümmell's disease with thoracolumbar kyphosis,to restore the normal alignment and sagittal balance can obtain a satisfactory radiographic and clinical short and medium-term effects.


Asunto(s)
Cifosis , Lordosis , Estudios de Seguimiento , Humanos , Cifosis/diagnóstico por imagen , Cifosis/cirugía , Lordosis/diagnóstico por imagen , Lordosis/cirugía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Estudios Retrospectivos , Sacro , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/cirugía , Resultado del Tratamiento
3.
Anal Chem ; 92(1): 707-715, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31762256

RESUMEN

Biofilms are microbial aggregates of microorganisms surrounded by a hydrogel-like matrix formed by extracellular polymeric substances (EPS). The formation of biofilms is intrinsically complex, from the attachment of microbial cells to the dispersion of the biofilm. Meanwhile, the three-dimensional framework built up by EPS changes with time and protects the microorganisms against environmental stress. Simultaneously acquiring chemical and structural information within the biofilm matrix is vital for the cognition and regulation of biofilms, yet it remains a great challenge due to the sample complexity and the limited approaches. In this study, confocal Raman microscopy and non-negative matrix factorization (NMF) analysis were combined to investigate spatiotemporal organization of Escherichia coli biofilms during development at molecular-level detail. The alternating non-negative least-squares (ANLS) approach was incorporated with the sequential coordinate-wise descent (SCD) algorithm to realize the NMF analysis for the large-scale hyperspectral data set. As a result, three components, including bacteria, protein, and polyhydroxybutyrate (PHB), were successfully resolved from the spectra of E. coli biofilm. Furthermore, the structural changes of biofilms could be visualized and quantified by their abundances derived from the NMF analysis, which might be related to the nutrient and oxygen gradient and physiological functions. This methodology provides a comprehensive understanding of the chemical constituents and their spatiotemporal distribution within the biofilm matrix. Furthermore, it also shows great potential for the analysis of unknown and complex biological samples with 3D Raman mapping.


Asunto(s)
Biopelículas , Escherichia coli/metabolismo , Algoritmos , Análisis Multivariante , Espectrometría Raman
4.
Appl Environ Microbiol ; 86(4)2020 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-31811044

RESUMEN

All nitroarene dioxygenases reported so far originated from Nag-like naphthalene dioxygenase of Gram-negative strains, belonging to group III of aromatic ring-hydroxylating oxygenases (RHOs). Gram-positive Rhodococcus sp. strain ZWL3NT utilizes 3-nitrotoluene (3NT) as the sole source of carbon, nitrogen, and energy for growth. It was also reported that 3NT degradation was constitutive and the intermediate was 3-methylcatechol. In this study, a gene cluster (bndA1A2A3A4) encoding a multicomponent dioxygenase, belonging to group IV of RHOs, was identified. Recombinant Rhodococcus imtechensis RKJ300 carrying bndA1A2A3A4 exhibited 3NT dioxygenase activity, converting 3NT into 3-methylcatechol exclusively, with nitrite release. The identity of the product 3-methylcatechol was confirmed using liquid chromatography-mass spectrometry. A time course of biotransformation showed that the 3NT consumption was almost equal to the 3-methylcatechol accumulation, indicating a stoichiometry conversion of 3NT to 3-methylcatechol. Unlike reported Nag-like dioxygenases transforming 3NT into 4-methylcatechol or both 4-methylcatechol and 3-methylcatechol, this Bph-like dioxygenase (dioxygenases homologous to the biphenyl dioxygenase from Rhodococcus sp. strain RHA1) converts 3NT to 3-methylcatechol without forming 4-methylcatechol. Furthermore, whole-cell biotransformation of strain RKJ300 with bndA1A2A3A4 and strain ZWL3NT exhibited the extended and same substrate specificity against a number of nitrobenzene or substituted nitrobenzenes, suggesting that BndA1A2A3A4 is likely the native form of 3NT dioxygenase in strain ZWL3NT.IMPORTANCE Nitroarenes are synthetic molecules widely used in the chemical industry. Microbial degradation of nitroarenes has attracted extensive attention, not only because this class of xenobiotic compounds is recalcitrant in the environment but also because the microbiologists working in this field are curious about the evolutionary origin and process of the nitroarene dioxygenases catalyzing the initial reaction in the catabolism. In contrast to previously reported nitroarene dioxygenases from Gram-negative strains, which originated from a Nag-like naphthalene dioxygenase, the 3-nitrotoluene (3NT) dioxygenase in this study is from a Gram-positive strain and is an example of a Bph-like nitroarene dioxygenase. The preference of hydroxylation of this enzyme at the 2,3 positions of the benzene ring to produce 3-methylcatechol exclusively from 3NT is also a unique property among the studied nitroarene dioxygenases. These findings will enrich our understanding of the diversity and origin of nitroarene dioxygenase in microorganisms.


Asunto(s)
Catecoles/metabolismo , Dioxigenasas/metabolismo , Rhodococcus/enzimología , Tolueno/análogos & derivados , Microorganismos Modificados Genéticamente/genética , Microorganismos Modificados Genéticamente/metabolismo , Complejos Multienzimáticos/metabolismo , Rhodococcus/genética , Rhodococcus/metabolismo , Tolueno/metabolismo
5.
J Sci Food Agric ; 99(13): 5752-5759, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31162681

RESUMEN

BACKGROUND: Sea cucumber (Stichopus japonicus) is easy to autolysis in response to a variety of environmental and mechanical factors. In the current study, collagen fibres were extracted from fresh sea cucumber body wall and then incubated with endogenous matrix metalloprotease (MMP) of sea cucumber. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), chemical analysis and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis were utilized to demonstrate the changes in collagen fibres, collagen fibrils and collagen proteins. Moreover, a verification experiment was also carried out to confirm the contribution of MMP to the autolysis of sea cucumber. RESULTS: Endogenous MMP caused complete depolymerization of collagen fibres into smaller collagen fibril bundles and collagen fibrils due to the fracture of proteoglycan interfibrillar bridges. Meanwhile, endogenous MMP also caused partial degradation of collagen fibrils by releasing soluble hydroxyproline and pyridinium cross-links. Furthermore, the treatment with MMP inhibitor (1,10-phenanthroline) prevented the autolysis of tissue blocks from S. japonicus dermis. CONCLUSION: Endogenous MMP was the key enzyme in the autolysis of sea cucumber, while its action still focused on high-level structures of collagens especially collagen fibres. © 2019 Society of Chemical Industry.


Asunto(s)
Autólisis , Metaloproteasas/metabolismo , Stichopus/enzimología , Stichopus/fisiología , Animales , Colágeno/metabolismo , Colágeno/ultraestructura , Hidroxiprolina/metabolismo , Metaloproteasas/genética , Microscopía Electrónica de Rastreo , Stichopus/ultraestructura
6.
J Food Sci Technol ; 56(9): 4166-4176, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31477988

RESUMEN

Whelks Neptunea arthritica cumingi Crosse and Neverita didyma were processed by hot air drying and changes of thei lipids and the mechanism involved were evaluated by analyzing peroxide value, thiobarbituric acid-reactive substances, total oxidation value, fatty acid composition, activities of lipases and lipoxygenase (LOX), as well as contents of triacylglycerol (TAG), free fatty acid (FFA), phosphatidylcholine (PC) and phosphatidylethanolamine (PE). The processing significantly decreased the contents of PC, PE and TAG but increased the content of FFA. The presence of acid lipase and phospholipase in whelk tissues and their activity preservation during processing suggest that the enzymes may help hydrolyze lipids. By contrast, the reduction of PC, PE and TAG was more pronounced than the increase in FFA in whelk tissues upon processing, indicating the oxidative degradation of FFA. LOX may play a role in lipid oxidation due to the stability of the starting components during processing.

7.
Nature ; 482(7384): 226-31, 2012 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-22286061

RESUMEN

Glioblastoma multiforme (GBM) is a lethal brain tumour in adults and children. However, DNA copy number and gene expression signatures indicate differences between adult and paediatric cases. To explore the genetic events underlying this distinction, we sequenced the exomes of 48 paediatric GBM samples. Somatic mutations in the H3.3-ATRX-DAXX chromatin remodelling pathway were identified in 44% of tumours (21/48). Recurrent mutations in H3F3A, which encodes the replication-independent histone 3 variant H3.3, were observed in 31% of tumours, and led to amino acid substitutions at two critical positions within the histone tail (K27M, G34R/G34V) involved in key regulatory post-translational modifications. Mutations in ATRX (α-thalassaemia/mental retardation syndrome X-linked) and DAXX (death-domain associated protein), encoding two subunits of a chromatin remodelling complex required for H3.3 incorporation at pericentric heterochromatin and telomeres, were identified in 31% of samples overall, and in 100% of tumours harbouring a G34R or G34V H3.3 mutation. Somatic TP53 mutations were identified in 54% of all cases, and in 86% of samples with H3F3A and/or ATRX mutations. Screening of a large cohort of gliomas of various grades and histologies (n = 784) showed H3F3A mutations to be specific to GBM and highly prevalent in children and young adults. Furthermore, the presence of H3F3A/ATRX-DAXX/TP53 mutations was strongly associated with alternative lengthening of telomeres and specific gene expression profiles. This is, to our knowledge, the first report to highlight recurrent mutations in a regulatory histone in humans, and our data suggest that defects of the chromatin architecture underlie paediatric and young adult GBM pathogenesis.


Asunto(s)
Ensamble y Desensamble de Cromatina/genética , Cromatina/genética , Glioblastoma/genética , Histonas/genética , Mutación/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Secuencia de Bases , Niño , Cromatina/metabolismo , Proteínas Co-Represoras , ADN Helicasas/genética , Análisis Mutacional de ADN , Exoma/genética , Perfilación de la Expresión Génica , Histonas/metabolismo , Humanos , Chaperonas Moleculares , Datos de Secuencia Molecular , Proteínas Nucleares/genética , Telómero/genética , Proteína p53 Supresora de Tumor/genética , Proteína Nuclear Ligada al Cromosoma X
8.
Anal Chem ; 89(7): 4264-4271, 2017 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-28252936

RESUMEN

Excitation-emission matrix (EEM) fluorescence spectroscopy coupled with parallel factor (PARAFAC) analysis has been widely applied to characterize dissolved organic matter (DOM) in aquatic and terrestrial systems. However, its application in environmental samples is limited because PARAFAC is not able to handle nontrilinear EEM data, leading to the overestimated number of components and incorrect decomposition results. In this work, a new method, parallel factor framework-clustering analysis (PFFCA), is proposed to resolve this problem. First, simulated data with different signal-to-noise ratios and intensities of nontrilinear structure were tested to confirm the robustness of PFFCA. The residual sum of squares (RSS) of PARAFAC was significantly higher than that of PFFCA (p < 0.037). Second, a set of data originating from a synthetic mixture of humic acid and bovine serum albumin was applied to compare with PARAFAC with known samples. PFFCA provided an estimation (R2 > 0.92) closer to actual EEM than PARAFAC (R2 > 0.81). Finally, to confirm the feasibility of PFFCA in analyzing natural samples, DOM-containing samples collected from both a polluted lake and river were tested, indicating that PFFCA provides a more precise estimation than PARAFAC. The results clearly indicate that PFFCA offers a robust approach for the unique decomposition of complex synthetic and natural samples, which is of great significance in understanding the characteristics of DOM in aqueous systems.

9.
Environ Sci Technol ; 51(9): 4812-4820, 2017 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-28406619

RESUMEN

The production and use of ionic liquids (ILs) increase the potential risk after their emission into the environment. After entering the environment, ILs will readily interact with dissolved organic matter (DOM), and their environmental behavior will be impacted by DOM, which is abundant in the environment and has various functional groups. However, to date, the interaction between DOM and ILs, especially long-chain ILs, remains unclear. In this work, the interaction between long-chain ILs and humic acid (HA), a representative DOM, was investigated using synchronous fluorescence, Fourier transform infrared spectroscopy, dynamic light scattering, and zeta potential techniques, which were integrated with two-dimensional correlation spectroscopy (2DCOS), hetero-2DCOS, and perturbation-correlation moving-window analyses. The results show that cation exchange by the carboxylic groups in humic-like fractions was primarily responsible for interaction at low IL concentrations. As a result, the decrease in electrostatic repulsion and the increase in hydrophobicity facilitated the loose aggregation of HA. With an increase in IL concentration, the aromatic and carbonyl groups were involved in the interaction via the π-π interaction and dipole-dipole interaction, respectively, which resulted in the disruption of the intramolecular hydrogen bond and promoted the compaction of HA under the hydrophobic effect. The intensity transition sequence of various groups in HA was elucidated more specifically by 2DCOS. With these results, a comprehensive view of the structural changes of DOM in its IL-binding process was obtained, and the fate and environmental impact of ILs could be better understood. Furthermore, the superior potential of such an integrated approach in investigating the complex interactions in the environment was also demonstrated.


Asunto(s)
Sustancias Húmicas , Líquidos Iónicos , Interacciones Hidrofóbicas e Hidrofílicas , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier
10.
Phys Chem Chem Phys ; 19(48): 32580-32588, 2017 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-29189841

RESUMEN

Extracellular electron transfer (EET) occurs from outer-membrane proteins to electron acceptors. Heme(ii) is the active center of outer-membrane proteins and delivers electrons to acceptors or mediators such as riboflavin, a redox active chromophore present in organisms. However, the EET mechanism via mediators, especially the electron transfer process from outer-membrane proteins to mediators, has not been well documented yet. In this work, the mechanism behind the electron transfer from heme(ii) to riboflavin is investigated by using in situ ultraviolet visible and fluorescence spectroelectrochemical analysis, which provides the information regarding the structural change and electrochemical characteristics of species in the electron transfer process. It is found that hemin(iii), the oxidized form of heme(ii), is electrolyzed to an intermediate "hemx(ii)" without structural changes, and is then transformed to heme(ii) by conjugating with riboflavin and its radicals. Heme(ii) is able to activate riboflavin reduction via a two-electron two-proton pathway in aqueous solution. The mechanisms proposed on the basis of experimental results are further confirmed by density functional theory calculations. The results about the electron transfer from hemx(ii) (or heme(ii)) to riboflavin are useful not only for understanding the EET mechanisms, but also for maximizing the role of riboflavin in biogeochemical cycling and environmental bioremediation.

11.
Chemphyschem ; 17(3): 358-63, 2016 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-26639164

RESUMEN

Understanding membrane fouling induced by dissolved organic matter (DOM) is of primary importance for developing effective fouling control and prevention strategies. In this work, we combine multivariate curve resolution-alternating least squares analysis with infrared attenuated total reflection mapping to explore the fouling process of microfiltration and ultrafiltration membranes caused by two typical DOMs, humic acid (HA) and bovine serum albumin (BSA). The spectral contributions of different foulants and the membrane substrate were successfully discriminated, thereby enabling the diagnosis of fouling origins. Membrane fouling caused by HA is more severe than that by BSA. Three periods, the initial adsorption stage, the equilibrium stage, and the accumulation stage, were observed for the HA-induced fouling process. The integrated approach presented herein elegantly demonstrates the spatial and temporal characterization of membrane fouling processes, along with relative concentrations of the involved species, and suggests a promising perspective for understanding the interaction mechanisms between foulant species and membranes at the molecular level.


Asunto(s)
Membranas/química , Polivinilos/química , Animales , Bovinos , Sustancias Húmicas , Análisis de los Mínimos Cuadrados , Análisis Multivariante , Albúmina Sérica Bovina/química
12.
Environ Sci Technol ; 49(4): 2052-8, 2015 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-25611159

RESUMEN

Dissolved organic matter (DOM) is known to form strong complexes with heavy metals and thus governs the distribution, toxicity, bioavailability, and ultimate fate of heavy metals in the environment. The relevant aspects of metal-organic interactions remain unclear because the metal binding functionalities in DOM are substantially nonuniform and the availability of the models is limited. In this work, two-dimensional correlation spectroscopy (2DCOS) integrated with synchronous fluorescence and infrared absorption spectroscopy was used to explore the binding process of copper to DOM. A series of heterogeneous binding sites in humic acid (HA), a representative DOM, and the subsequent subtle changes of these sites within the molecular interactions were elucidated by the 2DCOS method. The band assignments and the correspondence between the results obtained by two spectral probes (synchronous fluorescence and infrared absorption spectra) were verified by hetero-2DCOS. Our results showed that, during the copper binding process, the carboxyl and polysaccharide groups gave the fastest responses to copper binding. Then fluorescence quenching of fluorescent humic-like moieties occurred with a vibrational change of the related functionalities, i.e., phenolic and aryl carboxylic groups, which further induces the fluorescence quenching of fulvic-like fractions. Finally, small amounts of amide and aliphatic groups participated in the copper binding after the fluorescence of the protein-like fraction decreased. With these promising results, a comprehensive picture of structural changes of HA during the copper binding process was developed, highlighting the superior potential of 2D heterospectral correlation spectroscopy in studying complex interactions in the environment.


Asunto(s)
Cobre/química , Sustancias Húmicas/análisis , Espectroscopía Infrarroja por Transformada de Fourier/instrumentación , Sitios de Unión , Fluorescencia , Metales Pesados/farmacología , Espectrometría de Fluorescencia/instrumentación
13.
J Low Genit Tract Dis ; 19(3): 207-11, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25171105

RESUMEN

OBJECTIVE: We conducted a pilot study of whether nonpathologists could accurately diagnose cervical precancer in biopsies using only a basic light microscope, evaluating p16 immunohistochemistry (p16 IHC) of biopsies, and video-based training for both. MATERIALS AND METHODS: Using biopsies collected as part of a screening study conducted in rural China, we randomly selected 50 biopsies with a precancerous diagnosis of cervical intraepithelial neoplasia grade 2 (CIN2) or more severe (CIN2+) and 50 biopsies with diagnosis of CIN less severe than CIN2, and stained them for p16 using a commercial IHC kit. Twelve nonpathologists of varying educational backgrounds living in Beijing, China received video training and were assigned one of 4 sets of 25 CIN2+ and 25 CIN less severe than CIN2 for evaluation. A pathologist reviewed all 100 cases. RESULTS: The mean sensitivity and specificity of the p16 IHC staining scored by the nonpathologists were 91.7% and 94.1%, respectively, compared to scoring by the pathologist. The readers and the pathologist agreed on p16 IHC scoring for 42 (84%) of the 50 slides of CIN less severe than CIN2 and 37 (74%) of the 50 CIN2+ slides. The mean sensitivity and specificity for consensus CIN2+ of p16 IHC as scored by the readers were 88% and 87%, respectively, versus an overall sensitivity and specificity by the pathologist of 96% and 92%, respectively. CONCLUSIONS: We demonstrated that nonpathologists can accurately diagnose CIN2+ using p16 IHC alone.


Asunto(s)
Proteínas de Neoplasias , Patología/educación , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Adulto , Beijing , Biomarcadores de Tumor/análisis , China , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Femenino , Humanos , Inmunohistoquímica , Masculino , Microscopía de Polarización , Proteínas de Neoplasias/análisis , Proyectos Piloto , Distribución Aleatoria , Servicios de Salud Rural , Facultades de Medicina , Sensibilidad y Especificidad , Grabación en Video , Adulto Joven
14.
Environ Sci Technol ; 48(19): 11119-26, 2014 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-25222835

RESUMEN

The elucidation of the interaction between TiO2 nanoparticles (NPs) and natural organic matter (NOM) can help one to better understand the fates, features, and environmental impacts of NPs. In this work, two-dimensional (2D) Fourier transformation infrared (FTIR) correlation spectroscopy (CoS) assisted by the fluorescence excitation-emission matrix (EEM) method is used to explore the interaction mechanism of humic acid (HA) with TiO2 NPs at a molecular level. The results show that the C═O bonds (carboxylate, amide, quinone, or ketone) and C-O bonds (phenol, aliphatic C-OH, and polysaccharide) of HA play important roles in their interaction with TiO2 NPs. The adsorption process of HA onto the surface of TiO2 NPs is different from the bonding process of the two species in solution. The forms of the relevant groups of HA and their consequent reaction with TiO2 NPs are affected to a great extent by the solution pH and the surface charge of NPs. The 2D-FTIR-CoS method is found to be able to construct a comprehensive picture about the NOM-TiO2 NPs interaction process. This 2D-FTIR-CoS approach might also be used to probe other complicated interaction processes in natural and engineered environments.


Asunto(s)
Sustancias Húmicas , Nanopartículas/química , Titanio/química , Adsorción , Ácidos Carboxílicos/química , Sustancias Húmicas/análisis , Nanopartículas/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Titanio/análisis
15.
J Spinal Disord Tech ; 27(8): E282-93, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24901880

RESUMEN

STUDY DESIGN: Literature review and meta-analysis. SUMMARY OF BACKGROUND DATA: Posterolateral fusion (PLF) and circumferential fusion (CF) were widely used in the treatment of lumbar spondylolisthesis. There was a great controversy over the preferred fusion method. OBJECTIVE: We performed a meta-analysis for determining which fusion method was better in lumbar spondylolisthesis. METHODS: A systematic search was conducted in MEDLINE, EMBASE, and the Cochrane Collaboration Library from January 1960 to December 2013. Comparative studies were selected according to eligibility criteria. Weighed mean differences (WMDs) and risk differences were calculated. The final strength of evidence was expressed as different levels recommended by the GRADE Working Group. RESULTS: Eight comparative studies were identified. There was less evidence that no significant difference was found between CF and PLF for clinical satisfaction [odds ratio (OR), 0.63; 95% confidence interval (95% CI), 0.30, 1.32; P=0.22)] and for complication rate (OR, 0.64; 95% CI, 0.23, 1.76; P=0.39). The PLF was more effective than the CF for the reduction of complication rate for patients with isthmic spondylolisthesis (OR, 0.44; 95% CI, 0.23, 0.86; P=0.02). There was no significant difference for fusion rate, reoperation rate, operating time, and blood loss. Subanalysis showed that the CF can increase the fusion rate of patients with isthmic spondylolisthesis (OR, 0.12; 95% CI, 0.01, 1.00; P=0.05). PLF was more effective than CF for the reduction in operating time (WMD=-75.68; 95% CI, -99.00, -52.37; P<0.00001), and CF was more effective than PLF for the restoration of segment lordosis, disk height, and spondylolisthesis. CONCLUSIONS: There was really no difference for clinical satisfaction, complication rate, fusion rate, reoperation rate, operating time, and blood loss. PLF can reduce complication rate and operating time. CF can improve fusion rate for individuals with isthmic spondylolisthesis and restore lumbar alignment. The level of evidence was low.


Asunto(s)
Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Espondilolistesis/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
16.
Artículo en Inglés | MEDLINE | ID: mdl-38809740

RESUMEN

In this article, we propose a novel spectral tensor layer for communication-free distributed deep learning. The overall framework is as follows: first, we represent the data in tensor form (instead of vector form) and replace the matrix product in conventional neural networks with the tensor product, which in effect imposes certain transformed-induced structure on the original weight matrices, e.g., a block-circulant structure; then, we apply a linear transform along a certain dimension to split the original dataset into multiple spectral subdatasets; as a result, the proposed spectral tensor network consists of parallel branches where each branch is a conventional neural network trained on a spectral subdataset with ZERO communication cost. The parallel branches are directly ensembled (i.e., the weighted sum of their outputs) to generate an overall network with substantially stronger generalization capability than that of each branch. Moreover, the proposed method enjoys a byproduct of decentralization gain in terms of memory and computation, compared with traditional networks. It is a natural yet elegant solution for heterogeneous data in federated learning (FL), where data at different nodes have different resolutions. Finally, we evaluate the proposed spectral tensor networks on the MNIST, CIFAR-10, ImageNet-1K, and ImageNet-21K datasets, respectively, to verify that they simultaneously achieve communication-free distributed learning, distributed storage reduction, parallel computation speedup, and learning with multiresolution data.

17.
World J Clin Cases ; 12(7): 1326-1332, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38524524

RESUMEN

BACKGROUND: Cellular myofibroma is a rare subtype of myofibroma that was first described in 2017. Its diagnosis is often challenging because of its relative rarity, lack of known genetic abnormalities, and expression of muscle markers that can be confused with sarcomas that have myogenic differentiation. Currently, scholars have limited knowledge of this disease, and published cases are few. Further accumulation of diagnostic and treatment experiences is required. CASE SUMMARY: A 16-year-old girl experienced left upper limb swelling for 3 years. She sought medical attention at a local hospital 10 months ago, where magnetic resonance imaging revealed a 5-cm soft tissue mass. Needle biopsy performed at a local hospital resulted in the diagnosis of a spindle cell soft tissue sarcoma. The patient was referred to our hospital for limb salvage surgery with endoprosthetic replacement. She was initially diagnosed with a synovial sarcoma. Consequently, clinical management with chemotherapy was continued for the malignant sarcoma. Our pathology department also performed fluorescence in situ hybridization for result validation, which returned negative for SS18 gene breaks, indicating that it was not a synovial sarcoma. Next-generation sequencing was used to identify the SRF-RELA rearrangement. The final pathological diagnosis was a cellular/myofibroblastic neoplasm with an SRF-RELA gene fusion. The patient had initially received two courses of chemotherapy; however, chemotherapy was discontinued after the final diagnosis. CONCLUSION: This case was misdiagnosed because of its rare occurrence, benign biological behavior, and pathological similarity to soft tissue sarcoma.

18.
J Orthop Surg Res ; 19(1): 388, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956678

RESUMEN

BACKGROUND: In patients undergoing total joint arthroplasty (TJA), the administration of dexamethasone may contribute to perioperative blood glucose (BG) disturbances, potentially resulting in complications, even in patients without diabetes. This study aimed to demonstrate the impact of different administration regimens of dexamethasone in postoperative BG levels. METHODS: In this randomized, controlled, double-blind trial, 136 patients without diabetes scheduled for TJA were randomly assigned to three groups: two perioperative saline injections (Group A, placebo); a single preoperative injection of 20 mg dexamethasone and a postoperative saline injection (Group B), and two perioperative injections of 10 mg dexamethasone (Group C). Primary outcomes were the postoperative fasting blood glucose (FBG) levels. Secondary outcome parameters were the postoperative postprandial blood glucose (PBG) levels. Postoperative complications within 90 days were also recorded. Risk factors for FBG ≥ 140 mg/dl and PBG ≥ 180 mg/dl were investigated. RESULTS: Compared to Group A, there were transient increases in FBG and PBG on postoperative days (PODs) 0 and 1 in Groups B and C. Statistical differences in FBG and PBG among the three groups were nearly absent from POD 1 onward. Both dexamethasone regimens did not increase the risk for postoperative FBG ≥ 140 mg/dl or PBG ≥ 180 mg/dl. Elevated preoperative HbA1c levels may increase the risk of postoperative FBG ≥ 140 mg/dl or PBG ≥ 180 mg/dl, respectively. CONCLUSION: Perioperative intravenous high-dose dexamethasone to patients without diabetes has transient effects on increasing BG levels after TJA. However, no differences were found between the split-dose and single high-dose regimens. The elevated preoperative HbA1c, but not the dexamethasone regimens were the risk factor for FBG ≥ 140 mg/dl and PBG ≥ 180 mg/dl. TRIAL REGISTRATION: Chinese Clinical Trail Registry, ChiCTR2300069473. Registered 17 March 2023, https://www.chictr.org.cn/showproj.html?proj=186760 .


Asunto(s)
Glucemia , Dexametasona , Humanos , Dexametasona/administración & dosificación , Método Doble Ciego , Masculino , Femenino , Glucemia/metabolismo , Glucemia/efectos de los fármacos , Persona de Mediana Edad , Anciano , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/sangre , Inyecciones Intravenosas , Periodo Posoperatorio , Artroplastia de Reemplazo de Cadera/efectos adversos , Glucocorticoides/administración & dosificación , Artroplastia de Reemplazo/efectos adversos , Administración Intravenosa
19.
J Hazard Mater ; 465: 133420, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38183943

RESUMEN

Rapid and highly effective removal of hexavalent chromium (Cr(Ⅵ)) is extremely vital to water resources restoration and environmental protection. To overcome the pH limitation faced by most ionic absorbents, an always positive covalent organic nanosheet (CON) material was prepared and its Cr(VI) adsorption and removal capability was investigated in detail. As-prepared EB-TFB CON (TFB = 1,3,5-benzaldehyde, EB = ethidium bromide) shows strong electropositivity in the tested pH range of 1 ∼ 10, display a pH-independent Cr(VI) removal ability, and work well for Cr(VI) pollution treatment with good anti-interference capability and reusability in a wide pH range covering almost all Cr(VI)-contaminated real water samples, thus eliminating the requirement for pH adjustment. Moreover, the nanosheet structure, which is obtained by a facile ultrasonic-assisted self-exfoliation, endows EB-TFB CON with fully exposed active sites and shortened mass transfer channels, and the Cr(VI) adsorption equilibrium can be reached within 15 min with a high adsorption capacity of 280.57 mg·g-1. The proposed Cr(VI) removal mechanism, which is attributed to the synergetic contributions of electrostatic adsorption, ion exchange and chemical reduction, is demonstrated by experiments and theoretical calculations. This work not only provides a general Cr(VI) absorbent without pH limitation, but also presents a paradigm to prepare ionic CONs with relatively constant surface charges.

20.
Acta Neuropathol ; 125(5): 659-69, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23417712

RESUMEN

Recurrent mutations affecting the histone H3.3 residues Lys27 or indirectly Lys36 are frequent drivers of pediatric high-grade gliomas (over 30% of HGGs). To identify additional driver mutations in HGGs, we investigated a cohort of 60 pediatric HGGs using whole-exome sequencing (WES) and compared them to 543 exomes from non-cancer control samples. We identified mutations in SETD2, a H3K36 trimethyltransferase, in 15% of pediatric HGGs, a result that was genome-wide significant (FDR = 0.029). Most SETD2 alterations were truncating mutations. Sequencing the gene in this cohort and another validation cohort (123 gliomas from all ages and grades) showed SETD2 mutations to be specific to high-grade tumors affecting 15% of pediatric HGGs (11/73) and 8% of adult HGGs (5/65) while no SETD2 mutations were identified in low-grade diffuse gliomas (0/45). Furthermore, SETD2 mutations were mutually exclusive with H3F3A mutations in HGGs (P = 0.0492) while they partly overlapped with IDH1 mutations (4/14), and SETD2-mutant tumors were found exclusively in the cerebral hemispheres (P = 0.0055). SETD2 is the only H3K36 trimethyltransferase in humans, and SETD2-mutant tumors showed a substantial decrease in H3K36me3 levels (P < 0.001), indicating that the mutations are loss-of-function. These data suggest that loss-of-function SETD2 mutations occur in older children and young adults and are specific to HGG of the cerebral cortex, similar to the H3.3 G34R/V and IDH mutations. Taken together, our results suggest that mutations disrupting the histone code at H3K36, including H3.3 G34R/V, IDH1 and/or SETD2 mutations, are central to the genesis of hemispheric HGGs in older children and young adults.


Asunto(s)
Neoplasias Encefálicas/genética , Glioma/genética , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/metabolismo , Mutación/genética , Adolescente , Adulto , Factores de Edad , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Estudios de Casos y Controles , Niño , Estudios de Cohortes , Exoma , Glioma/metabolismo , Glioma/patología , Histona Metiltransferasas , Humanos , Lactante , Metilación , Persona de Mediana Edad , Clasificación del Tumor , Adulto Joven
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