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1.
Molecules ; 29(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38474681

RESUMEN

Z-scheme heterojunction Bi2WO6/g-C3N4 was obtained by a novel hydrothermal process; its photocatalysis-persulfate (PDS) activation for tetracycline (TC) removal was explored under solar light (SL). The structure and photoelectrochemistry behavior of fabricated samples were well characterized by FT-IR, XRD, XPS, SEM-EDS, UV-vis DRS, Mott-Schottky, PL, photocurrent response, EIS and BET. The critical experimental factors in TC decomposition were investigated, including the Bi2WO6 doping ratio, catalyst dosage, TC concentration, PDS dose, pH, co-existing ion and humic acid (HA). The optimum test conditions were as follows: 0.4 g/L Bi2WO6/g-C3N4 (BC-3), 20 mg/L TC, 20 mg/L PDS and pH = 6.49, and the maximum removal efficiency of TC was 98.0% in 60 min. The decomposition rate in BC-3/SL/PDS system (0.0446 min-1) was 3.05 times higher than that of the g-C3N4/SL/PDS system (0.0146 min-1), which might be caused by the high-efficiency electron transfer inside the Z-scheme Bi2WO6/g-C3N4 heterojunction. Furthermore, the photogenerated hole (h+), superoxide (O2•-), sulfate radical (SO4•-) and singlet oxygen (1O2) were confirmed as the key oxidation factors in the BC-3/SL/PDS system for TC degradation by a free radical quenching experiment. Particularly, BC-3 possessed a wide application potential in actual antibiotic wastewater treatment for its superior catalytic performance that emerged in the experiment of co-existing components.

2.
BMC Genomics ; 24(1): 611, 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37828453

RESUMEN

Uniparental-inherited haploid genetic marker of Y-chromosome single nucleotide polymorphisms (Y-SNP) have the power to provide a deep understanding of the human evolutionary past, forensic pedigree, and bio-geographical ancestry information. Several international cross-continental or regional Y-panels instead of Y-whole sequencing have recently been developed to promote Y-tools in forensic practice. However, panels based on next-generation sequencing (NGS) explicitly developed for Chinese populations are insufficient to represent the Chinese Y-chromosome genetic diversity and complex population structures, especially for Chinese-predominant haplogroup O. We developed and validated a 639-plex panel including 633 Y-SNPs and 6 Y-Insertion/deletions, which covered 573 Y haplogroups on the Y-DNA haplogroup tree. In this panel, subgroups from haplogroup O accounted for 64.4% of total inferable haplogroups. We reported the sequencing metrics of 354 libraries sequenced with this panel, with the average sequencing depth among 226 individuals being 3,741×. We illuminated the high level of concordance, accuracy, reproducibility, and specificity of the 639-plex panel and found that 610 loci were genotyped with as little as 0.03 ng of genomic DNA in the sensitivity test. 94.05% of the 639 loci were detectable in male-female mixed DNA samples with a mix ratio of 1:500. Nearly all of the loci were genotyped correctly when no more than 25 ng/µL tannic acid, 20 ng/µL humic acid, or 37.5 µM hematin was added to the amplification mixture. More than 80% of genotypes were obtained from degraded DNA samples with a degradation index of 11.76. Individuals from the same pedigree shared identical genotypes in 11 male pedigrees. Finally, we presented the complex evolutionary history of 183 northern Chinese Hans and six other Chinese populations, and found multiple founding lineages that contributed to the northern Han Chinese gene pool. The 639-plex panel proved an efficient tool for Chinese paternal studies and forensic applications.


Asunto(s)
Pueblos del Este de Asia , Polimorfismo de Nucleótido Simple , Humanos , Genotipo , Reproducibilidad de los Resultados , Genética de Población , Haplotipos , Cromosomas Humanos Y/genética , ADN
3.
Molecules ; 28(13)2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37446624

RESUMEN

BiOCl/graphene aerogel graphene (BGA) was successfully obtained by in situ hydrothermal synthesis, and the chemical, structural, morphological, and photocatalytic properties were systematically characterized. BGA with the doping amount of BiOCl at 20% (BGA-4) exhibited the optimal activation efficiency for persulfate (PDS) on the degradation of methyl orange (MO) under simulated sunlight (SSL) illumination as compared to the pure graphene (GA) and aerogel composites with different BiOCl content. The influence of various reaction parameters on the MO removal efficiency, such as the reaction system, catalyst activator dose, PDS concentration, BiOCl doping amount, and the initial pH of the solution, was investigated. Under optimum conditions, the catalytic efficiency of BiOCl-doped GA with the mass ratio of 20% (BGA-4) was 5.61 times that of GA. The strengthening effect of BGA-4 benefited from the synergistic effect of 1O2, O2·- and the generation and rapid electron transfer of photo-induced electron (e-) in the BGA-4/SSL/PDS system. Considering the superior stability and recyclability of BGA-4, the BGA-4/SSL/PDS system exhibits great potential in actual wastewater treatment.


Asunto(s)
Grafito , Grafito/química , Luz Solar , Compuestos Azo , Transporte de Electrón
4.
Molecules ; 27(12)2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35745060

RESUMEN

Porous noble metal nanomaterials have attracted extensive attention due to their high specific surface area and surface plasmon resonance effect. However, it is difficult to form porous structures due to the high mobility and low reduction potential of noble metal precursors. In this article, we developed a facile method for preparing porous Ag with a controllable structure at room temperature. Two kinds of Ag crystals with different porous structures were successfully prepared by using AgCl cubes as sacrificial templates. Through the galvanic replacement reaction of Zn and AgCl, Ag crystals with a sponge-like porous structure were successfully prepared. Additionally, using NaBH4 as the reducing agent, we prepared granular porous Ag cubes by optimizing the amount of reducing agent. Both the sponge-like and granular porous Ag cubes have clean and accessible surfaces. In addition, we used the prepared two porous Ag cubes as substrate materials for SERS detection of five kinds of methamphetamine analogs. The experimental results show that the enhancement effect of granular porous Ag is better than that of sponge-like porous Ag. Furthermore, we probed the hot spot distribution of granular porous Ag by Raman mapping. By using granular porous Ag as the substrate material, we have achieved trace detection of 5 kinds of methamphetamine analogs including Ephedrine, Amphetamine, N-Methyl-1-(benzofuran-5-yl)propan-2-amine (5-MAPB), N-Methyl-1-(4-methoxyphenyl)propan-2-amine (PMMA) and N-Methyl-1-(4-fluorophenyl)propan-2-amine (4-FMA). Furthermore, to achieve qualitative differentiation of analogs with similar structures we performed density functional theoretical (DFT) calculations on the Raman spectra of the above analogs. The DFT calculations provided the vibrational frequencies, Raman activities, and normal mode assignment for each analog, enabling the qualitative differentiation of the above analogs.


Asunto(s)
Nanopartículas del Metal , Metanfetamina , Nanopartículas del Metal/química , Porosidad , Sustancias Reductoras , Plata/química , Espectrometría Raman/métodos
5.
Acta Radiol ; 62(5): 639-645, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32903024

RESUMEN

BACKGROUND: The psoas major (PM) can support the lumbar spine and plays an important role in lumbar movement and maintaining lumbar curvature. PURPOSE: To analyze morphological changes of PM and its relation with the severity of adolescent idiopathic scoliosis (AIS). MATERIAL AND METHODS: The study was conducted on patients with AIS (age range = 10-18 years) with primary lumbar scoliosis. The cross-sectional area (CSA) of the PM at the L1-L5 levels were measured. The CSA of the PM in patients with AIS was compared with the average CSA of the PM in age-matched controls. The difference in PM at the apical vertebrae level was compared with the Cobb angle to determine the association between PM imbalance and severity of scoliosis. RESULTS: The CSA of the PM was larger on the concave side than the convex side at the apical vertebrae level and other lumber levels. Patients with a larger Cobb angle had statistically higher PM imbalance at the apical vertebrae level. The CSA of the PM on both the concave and convex sides of patients with AIS were larger than the average CSA of controls aged 16-18 years; however, there was no significant difference between patients with AIS and controls aged 10-15 years. CONCLUSION: There is a significant PM imbalance in patients with AIS before skeletal maturity, and the imbalance is related to the severity of scoliosis. The morphology of PM changed with the progression of scoliosis.


Asunto(s)
Músculos Psoas/diagnóstico por imagen , Escoliosis/diagnóstico por imagen , Adolescente , Factores de Edad , Niño , Femenino , Humanos , Región Lumbosacra , Imagen por Resonancia Magnética , Masculino , Radiografía , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
6.
BMC Musculoskelet Disord ; 22(1): 854, 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34625068

RESUMEN

BACKGROUND: The high signal of paravertebral muscle (PVM) on T2-weighted image (T2WI) is usually considered to be fatty degeneration. However, it is difficult to distinguish inflammatory edema from fatty degeneration on T2WI. The purpose of this study was to identify different types of PVM high signal in patients with low back pain (LBP) through magnetic resonance imaging (MRI) and histology. METHODS: Seventy patients with LBP underwent MRI. The signal change of multifidus both on T2WI and fat suppression image (FSI) was quantified by Image J. Furthermore, 25 of the 70 patients underwent surgery for degenerative lumbar disease and their multifidus were obtained during the operation. Histological analysis of the samples was performed by HE staining. RESULT: Three types of PVM signal changes were identified from the MRI. Type 1 (n = 36) indicated fatty degeneration characterized by a high signal on T2WI and low signal on FSI. High signal on both T2WI and FSI, signifying type 2 meant inflammatory edema (n = 9). Type 3 (n = 25) showed high signal on T2WI and partial signal suppression on FSI, which meant a combination of fatty degeneration and inflammatory edema. Histological results were consistent with MRI. Among the 25 patients who underwent surgery, type 1 (n = 14) showed adipocytes infiltration, type 2 (n = 3) showed inflammatory cells infiltration and type 3 (n = 8) showed adipocytes and inflammatory cells infiltration. CONCLUSION: From our results, there are three types of pathological changes in patients with PVM degeneration, which may help to decide on targeted treatments for LBP.


Asunto(s)
Dolor de la Región Lumbar , Atrofia Muscular , Estudios Transversales , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Dolor de la Región Lumbar/patología , Imagen por Resonancia Magnética , Atrofia Muscular/patología , Músculos Paraespinales/patología
7.
J Cell Mol Med ; 24(6): 3582-3592, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32040269

RESUMEN

Cartilage endplate (CEP) degeneration has been considered as one of important factors related to intervertebral disc degeneration (IVDD). Previous researches have showed that Rac1 played a pivotal role in chondrocyte differentiation. However, the effect of Rac1 during the process of CEP degeneration remains unclear. Herein, we explored the effect of Rac1 on CEP degeneration and elucidated the underlying molecular mechanism. We found expression of Rac1-GTP increased in human-degenerated CEP tissue and IL-1ß-stimulated rat endplate chondrocytes (EPCs). Our study revealed that Rac1 inhibitor NSC23766 treatment promoted the expression of collagen II, aggrecan and Sox-9, and decreased the expression of ADTAMTS5 and MMP13 in IL-1ß-stimulated rat EPCs. Moreover, we also found that NSC23766 could suppress the activation of Wnt/ß-catenin pathway, suggesting that the beneficial effects of Rac1 inhibition in EPCs are mediated through the Wnt/ß-catenin signalling. Besides, puncture-induced rats models showed that NSC23766 played a protective role on CEP and disc degeneration. Collectively, these findings demonstrated that Rac1 inhibition delayed the EPCs degeneration and its potential mechanism may be associated with Wnt/ß-catenin pathway regulation, which may help us better understand the association between Rac1 and CEP degeneration and provide a promising strategy for delaying the progression of IVDD.


Asunto(s)
Aminoquinolinas/farmacología , Cartílago/patología , Degeneración del Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/prevención & control , Pirimidinas/farmacología , Vía de Señalización Wnt , Proteína de Unión al GTP rac1/antagonistas & inhibidores , Animales , Cartílago/efectos de los fármacos , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Condrocitos/patología , Modelos Animales de Enfermedad , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Humanos , Interleucina-1beta/farmacología , Degeneración del Disco Intervertebral/patología , Ratas Sprague-Dawley , Factor de Transcripción SOX9/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo , Proteína de Unión al GTP rac1/metabolismo
8.
Acta Radiol ; 61(8): 1050-1056, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31795729

RESUMEN

BACKGROUND: The anatomical features of the thoracic nerve roots in connection with intervertebral discs may prevent surgery-related complications and improve patients' neurological functional status during thoracic spine surgery. There is limited literature evidence regarding this concept using cadavers. PURPOSE: To elucidate the qualitative anatomical features of the thoracic nerve roots in connection with intervertebral discs. MATERIAL AND METHODS: Fifteen formalin-preserved spine specimens were used in this study. Small pieces of stainless-steel wires were placed along the root sleeves from their points of origin, after exposing the dural sac and bilateral nerve roots. The standard anteroposterior and lateral radiographs were taken after the placement of the wires. Measurements were done on radiographs using the picture archiving communication system. RESULTS: Take-off angles of the nerve roots at the coronal plane gradually increased from the level of T2 (36.1°±2.72°) to T9 (84.1°±1.84°) and from T9, it decreased to T12 (46.3° ± 2.67°). Similar variation tendency was discovered in take-off angles of the nerve roots at the sagittal plane. No consistent tendency was found both in the distance from the origin of the root sleeve to its superior and inferior vertebral endplate. Distance from the origin of the root sleeve to the posterior midline (DM) exponentially decreased from T1 (8.2 ± 0.87 mm) to T4 (6.0 ± 0.93 mm). It slowly increased from T5 (5.5 ± 0.68 mm) to T12 (10.9 ± 1.79 mm), with T5 having the smallest DM. Distance between the origins of neighboring nerve roots showed an obvious increase from the T1-T2 interval (23.1 ± 2.22 mm) to T7-T8 interval (30.9 ± 2.68 mm). However, it progressively decreased at the T10-T11 interval (26.0 ± 2.40 mm). CONCLUSION: The dimensions of the thoracic nerve roots vary greatly from T1 to T12 intervertebral discs. Sound knowledge of these anatomical features of the thoracic nerve is mandatory for the thoracic spine surgery, especially in the posterolateral approach and transforaminal endoscopic surgery.


Asunto(s)
Disco Intervertebral/diagnóstico por imagen , Disco Intervertebral/inervación , Raíces Nerviosas Espinales/anatomía & histología , Raíces Nerviosas Espinales/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/inervación , Adulto , Anciano , Cadáver , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Adulto Joven
9.
Molecules ; 24(17)2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31480623

RESUMEN

As the number of macromolecular structures in the worldwide Protein Data Bank (wwPDB) continues to grow rapidly, more attention is being paid to the quality of its data, especially for use in aggregated structural and dynamics analyses. In this study, we systematically analyzed 3.5 Å regions around all metal ions across all PDB entries with supporting electron density maps available from the PDB in Europe. All resulting metal ion-centric regions were evaluated with respect to four quality-control criteria involving electron density resolution, atom occupancy, symmetry atom exclusion, and regional electron density discrepancy. The resulting list of metal binding sites passing all four criteria possess high regional structural quality and should be beneficial to a wide variety of downstream analyses. This study demonstrates an approach for the pan-PDB evaluation of metal binding site structural quality with respect to underlying X-ray crystallographic experimental data represented in the available electron density maps of proteins. For non-crystallographers in particular, we hope to change the focus and discussion of structural quality from a global evaluation to a regional evaluation, since all structural entries in the wwPDB appear to have both regions of high and low structural quality.


Asunto(s)
Bases de Datos de Proteínas , Metales/química , Cristalografía por Rayos X , Iones , Electricidad Estática
10.
J Xray Sci Technol ; 27(3): 443-451, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30856155

RESUMEN

PURPOSE: To investigate associations between the clinicopathologic features and CT perfusion parameters of triple-negative breast cancer (TNBC) and non-TNBC using low-dose computed tomography perfusion imaging (LDCTPI), and to find potential clinical applications in the prognosis assessment of TNBC. MATERIALS AND METHODS: A total of 60 patients with breast cancer confirmed by pathological examination were studied prospectively using LDCTPI on a 64-slice spiral CT scanner. The acquired volume data were used for calculations, mapping, and analysis by using a tumor perfusion protocol in the CT perfusion software package to measure 2 parameters namely, blood flow (BF), and permeability surface (PS) area product. Patients were grouped into TNBC (n = 27) and non-TNBC (n = 33) subtypes. Associations between these two subtypes and clinicopathologic characteristics were evaluated by both univariate and multivariate logistic regression. CT perfusion parameters values were compared for clinicopathologic characteristics using independent 2-sample t test. RESULTS: TNBC displayed higher CT perfusion parameters values (BF: 57.56±10.94 vs 52.70±7.79 mL/100 g/min, p = 0.006; PS: 38.98±9.46 vs 33.39±8.07 mL/100 g/min, p = 0.001) than non-TNBC. In addition, breast cancer with poorly histologic grade or positive Ki-67 expression showed higher BF and PS values than those with well and moderately histologic grade or negative Ki-67 expression (p < 0.05). TNBC had poorer histologic grade (P = 0.032) and higher Ki-67 expression (P = 0.013) than non-TNBC. CONCLUSION: LDCTPI is a functional imaging technology from the perspective of hemodynamics with potential of clinical applications. The BF and PS values were higher in TNBC patient group than non-TNBC group. TNBC patients also have poorer clinicopathologic outcome.


Asunto(s)
Imagen de Perfusión/métodos , Tomografía Computarizada Espiral/métodos , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Proyectos Piloto , Pronóstico , Interpretación de Imagen Radiográfica Asistida por Computador , Programas Informáticos , Neoplasias de la Mama Triple Negativas/irrigación sanguínea , Neoplasias de la Mama Triple Negativas/patología
11.
J Environ Sci (China) ; 77: 32-42, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30573096

RESUMEN

In this study, the characteristics of fine particles before and after wet flue gas desulfurization (WFGD) in three coal-fired heating boilers in northern China were investigated by using a dilution-based emission sampling experimental system. The influences of the WFGD process on the mass and number concentrations as well as the chemical composition of fine particles were analyzed. The removal efficiency of desulfurization processes on particulate matter mass was 30.06%-56.25% for the three study units. The WFGD had a great influence on the size distributions of particle mass concentration and number concentration. A significant increase in the number and mass concentration of particles in the size range of 0.094-0.946 µm was observed. The water-soluble ion content accounted for a very large proportion of PM2.5 mass, and its proportion in PM2.5 increased from 28.39%-41.08% to 48.96%-61.21% after the WFGD process for the three units. The desulfurizing process also drastically increased the proportion of cation component (Ca2+ for unit A, Mg2+ for unit B, and Na+ for unit C) and the proportion of SO42- in PM2.5, and it increased the CE/AE values of PM2.5 from 0.82-0.98 to 0.93-1.27 for the three study units.


Asunto(s)
Carbón Mineral , Gases/química , Tamaño de la Partícula , Material Particulado/química , Centrales Eléctricas , Azufre/química
12.
Chem Pharm Bull (Tokyo) ; 66(4): 410-415, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29415905

RESUMEN

The anti-inflammatory effects of (R)-2-(1H-Imidazol-1-yl) ethyl-3-(1H-indol-3-yl)-2-(2-p-tolylacetamido)propanamide (RH-1402), a previous designed small molecule Gastrin releasing peptide (GRP) antagonist were evaluated in adjuvant-induced arthritic model of rats, and the inhibitory effect on neutrophil migration induced by GRP was determined by a transwell system experiment in vitro. The arthritis was induced by injection of Complete Freund's Adjuvant (CFA) containing 10 mg/mL of heat killed mycobacterium into the left hind footpad. Experimental rats were randomly divided into 6 groups, including control, placebo, positive control group, RH-1402 of low/middle/high dose group. Disease incidence and severity was evaluated through scoring of the paw edema and histologic features of joint synovial. Blood of all experimental rats was collected for interleukin 1ß (IL-1ß) and tumor necrosis factor α (TNF-α) cytokine levels. A transwell system was used to investigate whether RH-1402 would inhibit neutrophils migrating up a gradient of GRP in vitro. RH-1402 (5 and 10 mg/kg) significantly decreased adjuvant induced increased arthritis index during the administration period (days 14-20). Significant inhibition of joint synovial histological features can be found in the RH-1402 treated group, including alleviated Hyperplasia, Inflammatory of infiltration and activation of pannus formation. It also suppressed TNF-α and IL-1ß level. Five and 10 mg/kg of RH-1402 significantly inhibited the effect of GRP on neutrophil migration with a dose dependent relationship. These findings indicate that RH-1402 have potential protective anti-inflammatory effects on experimental models of arthritis.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Artritis Experimental/tratamiento farmacológico , Receptores de Bombesina/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Artritis Experimental/inducido químicamente , Artritis Experimental/patología , Adyuvante de Freund/administración & dosificación , Ratas , Ratas Sprague-Dawley , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química
13.
J Sci Food Agric ; 98(6): 2215-2222, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28963727

RESUMEN

BACKGROUND: Boletaceae mushrooms are wild-grown edible mushrooms that have high nutrition, delicious flavor and large economic value distributing in Yunnan Province, China. Traceability is important for the authentication and quality assessment of Boletaceae mushrooms. In this study, UV-visible and Fourier transform infrared (FTIR) spectroscopies were applied for traceability of 247 Boletaceae mushroom samples in combination with chemometrics. RESULTS: Compared with a single spectroscopy technique, data fusion strategy can obviously improve the classification performance in partial least square discriminant analysis (PLS-DA) and grid-search support vector machine (GS-SVM) models, for both species and geographical origin traceability. In addition, PLS-DA and GS-SVM models can provide 100.00% accuracy for species traceability and have reliable evaluation parameters. For geographical origin traceability, the accuracy of prediction in the PLS-DA model by data fusion was just 64.63%, but the GS-SVM model based on data fusion was 100.00%. CONCLUSION: The results demonstrated that the data fusion strategy of UV-visible and FTIR combined with GS-SVM could provide a higher synergic effect for traceability of Boletaceae mushrooms and have a good generalization ability for the comprehensive quality control and evaluation of similar foods. © 2017 Society of Chemical Industry.


Asunto(s)
Agaricales/química , Espectrofotometría Ultravioleta/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Agaricales/clasificación , China , Análisis Discriminante , Geografía , Control de Calidad , Máquina de Vectores de Soporte
14.
Proteins ; 85(5): 938-944, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28168746

RESUMEN

Recent papers highlight the presence of large numbers of compressed angles in metal ion coordination geometries for metalloprotein entries in the worldwide Protein Data Bank, due mainly to multidentate coordination. The prevalence of these compressed angles has raised the controversial idea that significantly populated aberrant or even novel coordination geometries may exist. Some of these papers have undergone severe criticism, apparently due to views held that only canonical coordination geometries exist in significant numbers. While criticism of controversial ideas is warranted and to be expected, we believe that a line was crossed where unfair criticism was put forth to discredit an inconvenient result that compressed angles exist in large numbers, which does not support the dogmatic canonical coordination geometry view. We present a review of the major controversial results and their criticisms, pointing out both good suggestions that have been incorporated in new analyses, but also unfair criticism that was put forth to support a particular view. We also suggest that better science is enabled through: (i) a more collegial and collaborative approach in future critical reviews and (ii) the requirement for a description of methods and data including source code and visualizations that enables full reproducibility of results. Proteins 2017; 85:938-944. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Biología Computacional/ética , Complejos de Coordinación/química , Difusión de la Información/ética , Metaloproteínas/química , Metales/química , Biología Computacional/tendencias , Bases de Datos de Proteínas , Humanos , Conformación Proteica , Reproducibilidad de los Resultados
15.
Proteins ; 85(5): 885-907, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28142195

RESUMEN

Metalloproteins bind and utilize metal ions for a variety of biological purposes. Due to the ubiquity of metalloprotein involvement throughout these processes across all domains of life, how proteins coordinate metal ions for different biochemical functions is of great relevance to understanding the implementation of these biological processes. Toward these ends, we have improved our methodology for structurally and functionally characterizing metal binding sites in metalloproteins. Our new ligand detection method is statistically much more robust, producing estimated false positive and false negative rates of ∼0.11% and ∼1.2%, respectively. Additional improvements expand both the range of metal ions and their coordination number that can be effectively analyzed. Also, the inclusion of additional quality control filters has significantly improved structure-function Spearman correlations as demonstrated by rho values greater than 0.90 for several metal coordination analyses and even one rho value above 0.95. Also, improvements in bond-length distributions have revealed bond-length modes specific to chemical functional groups involved in multidentation. Using these improved methods, we analyzed all single metal ion binding sites with Zn, Mg, Ca, Fe, and Na ions in the wwPDB, producing statistically rigorous results supporting the existence of both a significant number of unexpected compressed angles and subsequent aberrant metal ion coordination geometries (CGs) within structurally known metalloproteins. By recognizing these aberrant CGs in our clustering analyses, high correlations are achieved between structural and functional descriptions of metal ion coordination. Moreover, distinct biochemical functions are associated with aberrant CGs versus nonaberrant CGs. Proteins 2017; 85:885-907. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Calcio/química , Complejos de Coordinación/química , Hierro/química , Magnesio/química , Metaloproteínas/química , Sodio/química , Zinc/química , Sitios de Unión , Cationes Bivalentes , Cationes Monovalentes , Análisis por Conglomerados , Bases de Datos de Proteínas , Unión Proteica , Conformación Proteica , Proteómica/métodos
16.
Eur Spine J ; 26(7): 1878-1883, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28102450

RESUMEN

PURPOSE: Percutaneous kyphoplasty (PKP) is a minimally invasive procedure for the treatment of osteoporotic vertebral compression fractures (OVCFs). It is generally considered that there is little blood loss during the surgery. However, a significant perioperative hidden blood loss (HBL) is neglected. This study was to examine the amount of HBL and determine the influential factors during PKP. METHODS: From January 2015 to January 2016, 115 patients with OVCFs who were scheduled to have a PKP were enrolled in this study. The factors analyzed included gender, age, body mass index (BMI), percentage of vertebral height loss, percentage of vertebral height restoration, number of fracture levels, bone mineral density (BMD), duration of symptom, cement leakage, and other internal diseases (hypertension, diabetes mellitus). According to Gross's formula, each patient's height, weight, and pre-operative and post-operative hematocrit were recorded and used for calculating the blood loss. Influential factors were further analyzed by multivariate linear regression analysis and t test. RESULTS: The mean HBL was 282 ± 162 mL (mL) and the post-operative Hb loss was 8.7 ± 5.4 g per liter (g/L). According to multivariate linear regression analysis, patients with severe vertebral height loss (P = 0.016), better vertebral height restoration (P = 0.038), and multi-segmental vertebral fractures (P = 0.000) had a higher amount of HBL. Fresh fractures (P = 0.008) and cement leakage (P = 0.004) were also important factors to increase HBL, whereas gender (P = 0.642), age (P = 0.203), BMI (P = 0.075), hypertension (P = 0.099), diabetes mellitus (P = 0.905), and BMD (P = 0.521) were not correlate with HBL. When we compared the incidence of anemia between pre-operative and post-operative, we found that the incidence of anemia was significantly associated with HBL (P = 0.000). CONCLUSIONS: HBL cannot be ignored in perioperative period, especially for poor physical condition and multiple fractures patients. Having a correct understanding of HBL can help improve clinical assessment capabilities, ensuring patients' safety.


Asunto(s)
Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Fracturas por Compresión/cirugía , Cifoplastia/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Fracturas Osteoporóticas/cirugía , Hemorragia Posoperatoria/etiología , Fracturas de la Columna Vertebral/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Cifoplastia/métodos , Modelos Lineales , Masculino , Persona de Mediana Edad , Hemorragia Posoperatoria/diagnóstico , Hemorragia Posoperatoria/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
17.
Eur Spine J ; 25(12): 4199-4207, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27554355

RESUMEN

PURPOSE: To evaluate the feasibility of cortical bone trajectory (CBT) screws fixation via pedicle or pedicle rib unit in the cadaveric thoracic spine (T9-T12). METHODS: Computed tomography (CT) images of 100 patients are analyzed by multiplanar reconstruction. Ten cadaveric thoracic spines are used to insert 4.5 × 35.0 mm CBT screws at all levels from T9 to T12. RESULTS: Maximal screw length obtained by CT has a tendency to gradually increase from T9 (29.64 mm) to T12 (32.84 mm), and the difference reaches significant level at all levels except T9 versus T10 (P < 0.01). Maximal screw diameter increases from T9 (4.92 mm) to T12 (7.47 mm) and the difference reaches significant level among all levels (P < 0.01). Lateral angle increases from T9 (7.37°) to T12 (10.47°), and the difference reaches significant level among all levels except T11 versus T12. Cephalad angle from T9 to T12 are 19.03°, 22.10°, 25.62° and 27.50° (P < 0.01), respectively. The percentage of the inner and outer pedicle breakage are 2.5 and 22.5 %, respectively. The violation of lateral pedicle wall occurs at T9 and T10, especially for women at T9. CONCLUSIONS: Both radiographic and cadaveric studies establish the feasibility of CBT screws placement via pedicle or pedicle rib unit in the lower thoracic spine (T9-T12). Furthermore, our measurements are also useful for application of this technique.


Asunto(s)
Hueso Cortical/diagnóstico por imagen , Procedimientos Ortopédicos/métodos , Tornillos Pediculares , Vértebras Torácicas/cirugía , Adulto , Anciano , Cadáver , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Vértebras Torácicas/diagnóstico por imagen , Tomografía Computarizada por Rayos X
18.
Br J Neurosurg ; 30(1): 86-90, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26313404

RESUMEN

PURPOSE: To determine whether unilateral pedicle screw fixation is comparable with unilateral pedicle screw and contralateral percutaneous transfacet screw fixation in single-level lumbar spinal fusion. METHODS: Fifty-eight patients were divided into either unilateral (n = 32) or unilateral pedicle screw and contralateral percutaneous transfacet screw fixation (n = 26) instrumentation groups. The operating time, blood loss, length of hospital stay, clinical outcomes, total lumbar scoliotic changes, and fusion and complication rates were compared between the two groups. RESULTS: There were no significant differences between the two groups in blood loss, length of hospital stay, clinical results, total lumbar scoliotic changes, and fusion and complication rates. There were significant differences in duration of operating time between 2 groups. CONCLUSIONS: Unilateral pedicle screw fixation may be as effective as unilateral PS with contralateral percutaneous transfacet screw fixation for the treatment of lumbar degenerative disorders.


Asunto(s)
Degeneración del Disco Intervertebral/cirugía , Vértebras Lumbares/patología , Vértebras Lumbares/cirugía , Región Lumbosacra/patología , Tornillos Pediculares , Fusión Vertebral , Adulto , Femenino , Humanos , Tiempo de Internación , Región Lumbosacra/cirugía , Masculino , Persona de Mediana Edad , Tempo Operativo , Fusión Vertebral/métodos
19.
J Orthop Sci ; 21(5): 609-13, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27183888

RESUMEN

BACKGROUND: No randomized controlled studies have confirmed the advantages of the joystick technique over the traditional manual traction. The objective of this study was to compare the results of the joystick technique and the traditional manual traction for facilitating closed reduction of pediatric supracondylar humeral fractures. METHODS: From February 2009 to December 2012, sixty eight children were included in this study. Group A included 34 fractures reduced by the joystick technique. Group B consisted of 34 fractures reduced by the traditional manual traction. Preoperative demographic data were comparable between the two groups. The operative time, fluoroscopy time, hospitalization time, time to bone union, complications were recorded in both groups. Radiologic and functional results were assessed using the Flynn scoring system. RESULTS: Closed reduction was successfully done in all the fractures of Group A while traditional closed manipulation was successfully done in 25 fractures of Group B and 9 fractures failed. There was a significant difference between the two groups in the rate of failed closed reduction (P = 0.004). The mean operative time was 30.5 ± 9.0 and 48.2 ± 16.4 min, and the mean fluoroscopy time was 25.4 ± 10.5 s and 55.0 ± 21.2 s in Group A and Group B, respectively. Both the operative time and fluoroscopy time were significantly longer in Group B (P < 0.001 and 0.001, respectively). However, there was no significant difference in terms of the mean hospitalization time, mean union time, total complications, the Flynn scores between the two groups (P > 0.05). CONCLUSIONS: The joystick technique should be chosen to facilitate closed reduction if traditional manual traction failed to yield an acceptable reduction.


Asunto(s)
Articulación del Codo/cirugía , Fijación de Fractura/métodos , Fracturas del Húmero/cirugía , Rango del Movimiento Articular/fisiología , Niño , Femenino , Fluoroscopía/métodos , Estudios de Seguimiento , Fijación de Fractura/instrumentación , Curación de Fractura/fisiología , Humanos , Fracturas del Húmero/diagnóstico por imagen , Puntaje de Gravedad del Traumatismo , Masculino , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Tempo Operativo , Pediatría , Radiografía/métodos , Recuperación de la Función , Tracción/métodos , Resultado del Tratamiento , Lesiones de Codo
20.
Proteins ; 83(8): 1470-87, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26009987

RESUMEN

Zinc metalloproteins are involved in many biological processes and play crucial biochemical roles across all domains of life. Local structure around the zinc ion, especially the coordination geometry (CG), is dictated by the protein sequence and is often directly related to the function of the protein. Current methodologies in characterizing zinc metalloproteins' CG consider only previously reported CG models based mainly on nonbiological chemical context. Exceptions to these canonical CG models are either misclassified or discarded as "outliers." Thus, we developed a less-biased method that directly handles potential exceptions without pre-assuming any CG model. Our study shows that numerous exceptions could actually be further classified and that new CG models are needed to characterize them. Also, these new CG models are cross-validated by strong correlation between independent structural and functional annotation distance metrics, which is partially lost if these new CGs models are ignored. Furthermore, these new CG models exhibit functional propensities distinct from the canonical CG models.


Asunto(s)
Biología Computacional/métodos , Metaloproteínas/química , Zinc/química , Algoritmos , Metaloproteínas/metabolismo , Relación Estructura-Actividad , Zinc/metabolismo
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