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1.
Sci Rep ; 14(1): 7437, 2024 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-38548857

RESUMEN

Aegilops umbellulata Zhuk., a wild diploid wheat-related species, has been used as a genetic resource for several important agronomic traits. However, its genetic variations have not been comprehensively studied. We sequenced RNA from 114 accessions of Ae. umbellulata to evaluate DNA polymorphisms and phenotypic variations. Bayesian clustering and phylogenetic analysis based on SNPs detected by RNA sequencing revealed two divergent lineages, UmbL1 and UmbL2. The main differences between them were in the sizes of spikes and spikelets, and culm diameter. UmbL1 is divided into two sublineages, UmbL1e and UmbL1w. These genetic differences corresponded to geographic distributions. UmbL1e, UmbL1w, and UmbL2 are found in Turkey, Iran/Iraq, and Greece, respectively. Although UmbL1e and UmbL1w were genetically similar, flowering time and other morphological traits were more distinct between these sublineages than those between the lineages. This discrepancy can be explained by the latitudinal and longitudinal differences in habitats. Specifically, latitudinal clines of flowering time were clearly observed in Ae. umbellulata, strongly correlated with solar radiation in the winter season. This observation implies that latitudinal differences are a factor in differences in the flowering times of Ae. umbellulata. Differences in flowering time could influence other morphological differences and promote genetic divergence between sublineages.


Asunto(s)
Aegilops , Aegilops/genética , Filogenia , Teorema de Bayes , Triticum/genética , Polimorfismo de Nucleótido Simple , Poaceae/genética
2.
Medicine (Baltimore) ; 103(8): e37043, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38394526

RESUMEN

The aim of this study was to investigate the prevalence of shoulder pain and analyze its association with socio-demographic factors, agricultural work-related conditions, and biomechanical factors among farmers on Jeju Island. We utilized initial survey data from the Safety for Agricultural Injury of Farmers' cohort study involving adult farmers on Jeju Island. The presence and characteristics of shoulder pain, socio-demographics, agricultural work-related conditions, and biomechanical factors were assessed using semi-structured questionnaires. A total of 1206 participants were analyzed for prevalence and associated risk factors using frequency and multivariate logistic regression analyses. The overall prevalence of shoulder pain was 17%. Multivariate logistic regression analysis, adjusted for significant socio-demographic and agricultural work-related condition variables, revealed that stress level, type of farming, and experiencing an agricultural injury within the preceding year were significantly associated with shoulder pain (stress level: "occasional," adjusted odds ratio [aOR], 1.581; 95% confidence interval [CI], 1.079-2.318; "frequent," aOR, 1.964; 95% CI, 1.205-3.200; and "extreme," aOR, 2.999; 95% CI, 1.480-6.074 vs "rarely"; type of farming: "orchard," aOR, 0.82; 95% CI, 0.597-1.124; "livestock," aOR, 0.225; 95% CI, 0.079-0.641 vs "field"; and experienced an agricultural injury within the past year: "yes," aOR, 2.078; 95% CI, 1.269-3.405). In addition, 3 biomechanical factors significantly contributed to shoulder pain: activities requiring significant power such as shoveling, pickaxing, and hammering; repetitive use of a particular body part; and constant elevation of the arm above the head. The findings highlight the importance of postural education, injury prevention, and psychological support in managing shoulder pain among farmers.


Asunto(s)
Agricultura , Dolor de Hombro , Adulto , Humanos , Estudios Transversales , Dolor de Hombro/epidemiología , Estudios Retrospectivos , Estudios de Cohortes , Prevalencia , Factores de Riesgo
3.
Clin J Pain ; 40(2): 92-98, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37982510

RESUMEN

OBJECTIVES: This study aimed to unidimensionally measure procedural pain at each percutaneous vertebroplasty (PVP) stage and evaluate the effectiveness of paravertebral nerve block (PVNB) in reducing procedural pain. METHODS: A retrospective study of prospectively collected data was conducted on 66 patients who underwent PVP for osteoporotic vertebral compression fractures. The patients were divided into 2 groups: group A (fluoroscopic-guided PVNB; 5 cm 3 of 0.75% ropivacaine on each side) and group B (local anesthesia). To investigate procedural pain associated with PVP, the visual analog scale score was assessed at each surgical stage: before the incision (stage 1), transpedicular approach (stage 2), and polymethylmethacrylate cement injection (stage 3). After the procedure, patients were asked about their surgical experience and satisfaction using the Iowa Satisfaction with Anesthesia Scale. Periprocedural complications were also recorded. RESULTS: A total of 63 patients (78.65 y of age) were finally enrolled: 30 from group A and 33 from group B. In both groups, a significant ≥2-point increase in procedural pain was observed during PVP compared with that during stage 1 ( P < 0.001). In stages 2 and 3, the pain intensity was significantly lower in group A ( P < 0.001). Upon discharge, the visual analog scale score improved in all groups; however, the Iowa Satisfaction with Anesthesia Scale score was significantly higher in group A ( P < 0.001). There was no difference in periprocedural complications between the two groups ( P = 0.743). CONCLUSION: PVP causes significant procedural pain, and PVNB is a potentially effective modality for enhancing patient satisfaction and reducing procedural pain.


Asunto(s)
Fracturas por Compresión , Bloqueo Nervioso , Fracturas Osteoporóticas , Dolor Asociado a Procedimientos Médicos , Fracturas de la Columna Vertebral , Vertebroplastia , Humanos , Vertebroplastia/efectos adversos , Vertebroplastia/métodos , Fracturas por Compresión/cirugía , Fracturas por Compresión/complicaciones , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Fracturas Osteoporóticas/complicaciones , Fracturas Osteoporóticas/cirugía , Bloqueo Nervioso/efectos adversos
4.
Medicina (Kaunas) ; 59(7)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37512142

RESUMEN

Chronic constipation can lead to fecal impaction in the large bowel, which can cause pressure necrosis followed by perforation, known as a stercoral ulcer. In extensive posterior thoracolumbar surgery, a long operation time, large blood loss, and perioperative narcotic use may aggravate constipation. Moreover, sacral root palsy due to cauda equina syndrome (CES) can lead to the deterioration of fecal impaction. This report describes the case of a 77-year-old woman with CES who presented with saddle anesthesia, neurogenic bladder, bowel incontinence, and paraplegia. Five days prior, she had undergone extended posterior lumbar interbody fusion from L1 to L5. Lumbar magnetic resonance imaging (MRI) showed an extended epidural hematoma. After urgent neural decompression, she gradually recovered from the saddle anesthesia, leg pain, and paraplegia over 3 weeks. Thereafter, the patient suddenly developed massive hematochezia and hemorrhagic shock. Urgent colonoscopy was performed, and a stercoral ulcer in the sigmoid colon was diagnosed. After 4 weeks of intensive care for hemorrhagic shock, pneumonia, and systemic sepsis, the patient was transferred to a general ward for intensive rehabilitation. One year after the operation, she was able to walk with assistance, and her urinary and bowel incontinence completely recovered. Chronic constipation, a common clinical problem, can sometimes cause relatively obscure but potentially life-threatening complications such as stercoral ulceration. Possible factors including advanced age, extensive spinal surgeries, prolonged operation time, significant blood loss, perioperative narcotic use, and the presence of spinal cord injury might contribute to the development of this condition. It highlights the importance of recognizing the potential development of stercoral ulcers in patients with CES and emphasizes the need for prompt diagnosis and management to avert catastrophic complications.


Asunto(s)
Síndrome de Cauda Equina , Impactación Fecal , Incontinencia Fecal , Choque Hemorrágico , Humanos , Femenino , Anciano , Síndrome de Cauda Equina/complicaciones , Úlcera/complicaciones , Impactación Fecal/complicaciones , Incontinencia Fecal/complicaciones , Choque Hemorrágico/complicaciones , Estreñimiento/etiología , Paraplejía/complicaciones , Hematoma , Narcóticos
5.
J Craniomaxillofac Surg ; 51(6): 387-392, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37355370

RESUMEN

Although surgical accuracy has been evaluated in bi-maxillary procedures, few studies have investigated the relationship between maxillary and mandibular accuracy. The present study evaluated the effect of maxillary impaction accuracy on mandibular surgical outcome. This cohort study analyzed skeletal class III patients who underwent planned maxillary impaction in bi-maxillary surgery. The primary predictor was the difference between the virtual plan and surgical outcome in the maxilla, as determined by three-dimensional (3D) and vertical differences. The secondary predictors were the planned 3D distances in the maxilla and mandible. The primary outcome was mandibular surgical accuracy, defined as the difference between the planned and actual outcomes, calculated as 3D Euclidean distance. The study included 73 patients. Increased differences between the planned and actual outcomes in the maxilla were associated with increased differences in the mandible. The post-operative position of the mandible was closer to the planned position when the position of the impacted maxilla was superior than when it was inferior to the planned position. Moving the maxilla closer to the planned position resulted in a more accurate mandibular position. These findings suggest that careful surgical procedures are needed to avoid inferior positioning of the maxilla during maxillary impaction surgery.


Asunto(s)
Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Diente Impactado , Humanos , Maxilar/cirugía , Estudios Retrospectivos , Estudios de Cohortes , Procedimientos Quirúrgicos Ortognáticos/métodos , Mandíbula/cirugía , Imagenología Tridimensional
6.
Pain Pract ; 22(4): 424-431, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34837304

RESUMEN

OBJECTIVES: Retrodiscal transforaminal (RdTF) epidural steroid injection (ESI) is clinically comparable to conventional transforaminal ESI and can avoid catastrophic complications. However, it poses a risk of inadvertent intradiscal, intravascular, and intrathecal injections. Therefore, we aimed to evaluate the feasibility of percutaneous epidural adhesiolysis (PEA) using the contralateral (Contra)-RdTF approach. METHODS: The electronic medical records of 332 patients with unilateral lumbar radiculopathy due to foraminal disk pathology were reviewed. Patients were categorized into two groups: Group A (ESI using the RdTF approach) and Group B (PEA using the Contra-RdTF approach). Effective pain relief (EPR; ≥50% pain relief from baseline) in patients was evaluated using the visual analog scale (VAS) at 4 and 12 weeks after the procedure. The presence of unintended fluoroscopic findings and complications was recorded. RESULTS: A total of 119 patients were enrolled in the final analysis: 81 in Group A and 38 in Group B. Both groups showed lesser VAS scores after 4 and 12 weeks than at baseline (p < 0.05). However, the proportion of patients with EPR was significantly greater in Group B after 12 weeks (p = 0.015). No complications, including intrathecal injection, infectious discitis, and neurologic deterioration, were reported. However, inadvertent intradiscal and intravascular injections were reported to be significantly higher in Group A than in Group B (14.8% and 0%, respectively; p = 0.009). CONCLUSIONS: Although applications of this study are limited by its retrospective design, the results suggest that PEA using the Contra-RdTF approach is feasible because it can achieve EPR and avoid unintended fluoroscopic findings.


Asunto(s)
Dolor de la Región Lumbar , Radiculopatía , Espacio Epidural , Humanos , Inyecciones Epidurales/métodos , Dolor de la Región Lumbar/tratamiento farmacológico , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares , Radiculopatía/tratamiento farmacológico , Radiculopatía/etiología , Radiculopatía/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
7.
Int J Mol Sci ; 22(23)2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34884569

RESUMEN

Toll-like receptors (TLRs) play a major role in the innate immune system. Several studies have shown the regulatory effects of TLR-mediated pathways on immune and inflammatory diseases. Dysregulated functions of TLRs within the endosomal compartment, including TLR7/9 trafficking, may cause systemic lupus erythematosus (SLE). TLR signaling pathways are fine-tuned by Toll/interleukin-1 receptor (TIR) domain-containing adapters, leading to interferon (IFN)-α production. This study describes a TLR inhibitor peptide 1 (TIP1) that primarily suppresses the downstream signaling mediated by TIR domain-containing adapters in an animal model of lupus and patients with SLE. The expression of most downstream proteins of the TLR7/9/myeloid differentiation factor 88 (MyD88)/IFN regulatory factor 7 signaling was downregulated in major tissues such as the kidney, spleen, and lymph nodes of treated mice. Furthermore, the pathological analysis of the kidney tissue confirmed that TIP1 could improve inflammation in MRL/lpr mice. TIP1 treatment downregulated many downstream proteins associated with TLR signaling, such as MyD88, interleukin-1 receptor-associated kinase, tumor necrosis factor receptor-associated factor 6, and IFN-α, in the peripheral blood mononuclear cells of patients with SLE. In conclusion, our data suggest that TIP1 can serve as a potential candidate for the treatment of SLE.


Asunto(s)
Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Inflamación/prevención & control , Lupus Eritematoso Sistémico/tratamiento farmacológico , Fragmentos de Péptidos/farmacología , Receptores Toll-Like/antagonistas & inhibidores , Animales , Humanos , Inflamación/etiología , Inflamación/metabolismo , Inflamación/patología , Lupus Eritematoso Sistémico/etiología , Lupus Eritematoso Sistémico/metabolismo , Lupus Eritematoso Sistémico/patología , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos MRL lpr , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo
8.
J Oral Maxillofac Surg ; 79(5): 1146.e1-1146.e25, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33539812

RESUMEN

PURPOSE: Accuracy in orthognathic surgery with virtual planning has been reported, but detailed analysis of accuracy according to anatomic location, including the mandibular condyle, is insufficient. The purpose of this study was to compare the virtual plan and surgical outcomes and analyze the degree and distribution of errors according to each anatomic location. PATIENTS AND METHODS: This retrospective cohort study evaluated skeletal class III patients, treated with bimaxillary surgery. The primary predictor was anatomic locations that consisted of right and left condyles, maxilla, and the distal segment of the mandible. Other variables were age and gender. The primary outcome was surgical accuracy, defined as mean 3-dimensional distance error, mean absolute error, and mean error along the horizontal, vertical, and anteroposterior axes between the virtual plan and surgical outcomes. Landmarks were compared using a computational method based on affine transformation with a 1-time landmark setting. The mean errors were visualized with multidimensional scattergrams. Bivariate and regression statistics were computed. RESULTS: This study included 52 patients, 26 men and 26 women, with a mean age of 21 years and 3 months. The mean 3D distance errors for condylar landmarks, maxillary landmarks, and landmarks on the distal segment of the mandible were 1.03, 1.25, and 2.24 mm, respectively. Condylar landmarks, maxillary landmarks, and the landmarks on the distal segment of the mandible were positioned at 0.49 mm inferior, 0.28 mm anterior, and 1.25 mm inferior, respectively. The landmark errors for the distal segment of the mandible exhibited a wider distribution than those for condylar and maxillary landmarks. CONCLUSIONS: Agreement between the planned and actual outcome aided by virtual surgical planning was highest for the condyles, followed by the maxilla, and the distal segment of the mandible. It is important to consider the tendency for surgical errors in each anatomic location during operations.


Asunto(s)
Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Cirugía Asistida por Computador , Adulto , Femenino , Humanos , Imagenología Tridimensional , Masculino , Mandíbula , Maxilar , Estudios Retrospectivos , Adulto Joven
9.
Int J Mol Sci ; 22(3)2021 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-33573068

RESUMEN

We aimed to characterize the salivary protein components and identify biomarkers in patients with systemic lupus erythematosus (SLE). A proteomic analysis using two-dimensional gel electrophoresis and mass spectrometry was performed to determine the alterations of salivary proteins between patients with SLE and healthy controls, and the concentrations of the candidate proteins were measured through Western blot analysis and the enzyme-linked immunosorbent assay. The 10 differentially expressed protein spots were immunoglobulin gamma-3 chain C region (IGHG3), immunoglobulin alpha-1 chain C region, protein S100A8, lactoferrin, leukemia-associated protein 7, and 8-oxoguanine DNA glycosylase. The patients with SLE exhibited enhanced salivary IGHG3 (3.9 ± 2.15 pg/mL) and lactoferrin (4.7 ± 1.8 pg/mL) levels compared to patients with rheumatoid arthritis (1.8 ± 1.01 pg/mL and 3.2 ± 1.6 pg/mL, respectively; p < 0.001 for both) or healthy controls (2.2 ± 1.64 pg/mL and 2.2 ± 1.7 pg/mL, respectively; p < 0.001 for both). The salivary IGHG3 levels correlated with the erythrocyte sedimentation rate (r = 0.26, p = 0.01), anti-double-stranded DNA (dsDNA) antibody levels (r = 0.25, p = 0.01), and nephritis (r = 0.28, p = 0.01). The proteomic analysis revealed that the salivary IGHG3 levels were associated with SLE and lupus disease activity, suggesting that salivary IGHG3 may be a promising noninvasive biomarker for SLE.


Asunto(s)
Inmunoglobulina G/análisis , Cadenas gamma de Inmunoglobulina/análisis , Lupus Eritematoso Sistémico/diagnóstico , Saliva/química , Adulto , Biomarcadores/análisis , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
J Rheum Dis ; 28(3): 133-142, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37475994

RESUMEN

Objective: Systemic lupus erythematosus (SLE) is a common chronic autoimmune inflammatory disease According to recent studies, signaling through Toll-like receptor (TLR) protein, which promotes the production of inflammatory cytokines, leads to the development of SLE TLR-inhibitory peptide 1 (TIP1) has been newly identified for the treatment of autoimmune diseases. Methods: The effect of TIP1 was analyzed in an SLE mouse model (MRL/lpr) The mice in the control treatment group (n=5) were administered an intravenous injection of phosphate-buffered saline twice weekly, whereas the mice in the TIP1 treatment group (n=6) were administered an intravenous injection of TIP1 (1 nmol/g) twice weekly MRL/mpj mice (n=5) were selected as normal controls The mice were injected for 4 weeks between 14 and 18 weeks of age, followed by assays of their spleen, kidneys, lymph nodes, serum, and urine. Results: The antinuclear antibody and inflammatory cytokine (interferon-α) in the serum as well as levels of albumin in the urine of the mice in the TIP1 treatment group had decreased when compared to those of mice in the control treatment group Kidney inflammation in mice in the TIP1 treatment group was alleviated The mRNA expression levels of TLR7- or TLR9-related downstream signaling molecules also decreased in all organs of the mice in the TIP1 treatment group. Conclusion: Intravenous treatment with TIP1 reduces symptoms and markers of inflammation in MRL/lpr mice Hence, TIP1 is a promising medication for the treatment of SLE.

11.
Clin Orthop Surg ; 11(1): 131-136, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30838118

RESUMEN

The approach we suggest was developed for cases in which the fourth and fifth lumbar and first sacral spinal nerves were affected in lumbar degenerative disc disease. Retrodiscal transforaminal epidural injection is known to be very effective for lumbar radiculopathy because of excellent access to primary pathology; however, access below L5 is often restricted by the anatomic characteristics of the L5-S1. In the translateral recess approach (TLR), proper final needle placement (i.e., in the axillary portion between the exiting and traversing nerve roots) can be achieved by setting the direction of the needle laterally and superiorly from the distal tip of the infra-adjacent spinous process toward the medial wall of the pedicle and neural foramen of the given level without neural injury. This approach is possible because of the wide interlaminar space in the L5-S1. Preganglionic epidural injection through TLR is an effective and safe spinal intervention for lumbosacral radiculopathy.


Asunto(s)
Inyecciones Epidurales/métodos , Radiculopatía/tratamiento farmacológico , Esteroides/administración & dosificación , Humanos , Degeneración del Disco Intervertebral/complicaciones , Vértebras Lumbares , Masculino , Persona de Mediana Edad , Radiculopatía/etiología , Sacro
12.
Medicine (Baltimore) ; 97(22): e10895, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29851813

RESUMEN

Lumbar fusion surgery was known to pose a greater risk of surgical glove perforation. However, there has been no study on the glove perforation that can transmit the blood-borne disease to the patient and surgical staff members in the posterior lumbar interbody fusion surgery (PLIFs).We performed a cross-sectional study to investigate the glove perforation during the PLIFs. The study included 37 consecutive patients (10 males and 27 females). All used gloves of surgical staff members, which included the surgeon, assistant surgeons, bone trimmer (who performed local bone trimming and interbody cage preparation), and scrub nurse were collected and were performed to the pinhole water infusion test. The characteristics (i.e., frequency and location of perforated glove) and relative risk of glove perforation were investigated for each participant. The independent risk factors influencing glove perforation were analyzed by multiple logistic regression analysis.The overall operative perforation rate which is a percentage of detected more than one glove perforated event in all cases was 51.4%. The overall glove perforation rate which is the percentage of perforated gloves in all gloves used for surgery was 3.8%. The relative risk of glove perforation by each participant was 2.38 in the surgeon (P = .002), 1.36 in the bone trimmer (P = .04), 1.36 in the scrub nurse (P = .04), and 1.19 in assistant surgeons (P = .13). And, the volume of trimmed local bone was analyzed as an independent risk factor for glove perforation (ORs = 1.310, P = .02).The overall operative perforation rate in PLIFs is higher than 50%. The surgeon, scrub nurse and bone trimmer were observed as a significant risk factor for glove perforation. And, the volume of trimmed local bone was analyzed as independent risk factor. Since the preparation of the interbody cage is essential for successful lumbar fusion surgery, the bone trimmer must pay attention to the glove perforation during this procedure.


Asunto(s)
Falla de Equipo/estadística & datos numéricos , Guantes Quirúrgicos , Fusión Vertebral/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
13.
Nat Commun ; 8(1): 1561, 2017 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-29146973

RESUMEN

Improving one property without sacrificing others is challenging for lithium-ion batteries due to the trade-off nature among key parameters. Here we report a chemical vapor deposition process to grow a graphene-silica assembly, called a graphene ball. Its hierarchical three-dimensional structure with the silicon oxide nanoparticle center allows even 1 wt% graphene ball to be uniformly coated onto a nickel-rich layered cathode via scalable Nobilta milling. The graphene-ball coating improves cycle life and fast charging capability by suppressing detrimental side reactions and providing efficient conductive pathways. The graphene ball itself also serves as an anode material with a high specific capacity of 716.2 mAh g-1. A full-cell incorporating graphene balls increases the volumetric energy density by 27.6% compared to a control cell without graphene balls, showing the possibility of achieving 800 Wh L-1 in a commercial cell setting, along with a high cyclability of 78.6% capacity retention after 500 cycles at 5C and 60 °C.

14.
Angew Chem Int Ed Engl ; 55(46): 14384-14388, 2016 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-27730753

RESUMEN

Flexible lithium-ion batteries are critical for the next-generation electronics. However, during the practical application, they may break under deformations such as twisting and cutting, causing their failure to work or even serious safety problems. A new family of all-solid-state and flexible aqueous lithium ion batteries that can self-heal after breaking has been created by designing aligned carbon nanotube sheets loaded with LiMn2 O4 and LiTi2 (PO4 )3 nanoparticles on a self-healing polymer substrate as electrodes, and a new kind of lithium sulfate/sodium carboxymethylcellulose serves as both gel electrolyte and separator. The specific capacity, rate capability, and cycling performance can be well maintained after repeated cutting and self-healing. These self-healing batteries are demonstrated to be promising for wearable devices.

15.
Small ; 12(5): 658-67, 2016 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-26662621

RESUMEN

Understanding the growth of graphene over Si species is becoming ever more important as the huge potential for the combination of these two materials becomes more apparent, not only for device fabrication but also in energy applications, particularly in Li-ion batteries. Thus, the drive for the direct fabrication of graphene over Si is crucial because indirect approaches, by their very nature, require processing steps that, in general, contaminate, damage, and are costly. In this work, the direct chemical vapor deposition growth of few-layer graphene over Si nanoparticles is systematically explored through experiment and theory with the use of a reducer, H2 or the use of a mild oxidant, CO2 combined with CH4 . Unlike the case of CH4 , with the use of CO2 as a mild oxidant in the reaction, the graphene layers form neatly over the surface and encapsulate the Si particles. SiC formation is also prevented. These structures show exceptionally good electrochemical performance as high capacity anodes for lithium-ion batteries. Density functional theory studies show the presence of CO2 not only prevents SiC formation but helps enhance the catalytic activity of the particles by maintaining an SiOx surface. In addition, CO2 can enhance graphitization.

16.
Nat Commun ; 6: 7393, 2015 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-26109057

RESUMEN

Silicon is receiving discernable attention as an active material for next generation lithium-ion battery anodes because of its unparalleled gravimetric capacity. However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life. Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation. The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers. When paired with a commercial lithium cobalt oxide cathode, the silicon carbide-free graphene coating allows the full cell to reach volumetric energy densities of 972 and 700 Wh l(-1) at first and 200th cycle, respectively, 1.8 and 1.5 times higher than those of current commercial lithium-ion batteries. This observation suggests that two-dimensional layered structure of graphene and its silicon carbide-free integration with silicon can serve as a prototype in advancing silicon anodes to commercially viable technology.

17.
Ann Dermatol ; 27(1): 111-3, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25673950
18.
ACS Nano ; 8(9): 9224-32, 2014 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-25171048

RESUMEN

The use of mild oxidants in chemical vapor deposition (CVD) reactions has proven enormously useful. This was also true for the CVD growth of carbon nanotubes. As yet though, the use of mild oxidants in the CVD of graphene has remained unexplored. Here we explore the use of CO2 as a mild oxidant during the growth of graphene over Ni with CH4 as the feedstock. Both our experimental and theoretical findings provide in-depth insight into the growth mechanisms and point to the mild oxidants playing multiple roles. Mild oxidants lead to the formation of a suboxide in the Ni, which suppresses the bulk diffusion of C species suggesting a surface growth mechanism. Moreover, the formation of a suboxide leads to enhanced catalytic activity at the substrate surface, which allows reduced synthesis temperatures, even as low as 700 °C. Even at these low temperatures, the quality of the graphene is exceedingly high as indicated by a negligible D mode in the Raman spectra. These findings suggest the use of mild oxidants in the CVD fabrication as a whole could have a positive impact.

19.
Prev Nutr Food Sci ; 19(2): 82-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25054106

RESUMEN

Yam (Dioscorea batatas Decne.) has long been used as a health food and oriental folk medicine because of its nutritional fortification, tonic, anti-diarrheal, anti-inflammatory, antitussive, and expectorant effects. Reactive oxygen species (ROS), which are known to be implicated in a range of diseases, may be important progenitors of carcinogenesis. The aim of this study was to investigate the modulatory effect of yam on antioxidant status and inflammatory conditions during azoxymethane (AOM)-induced colon carcinogenesis in male F344 rats. We measured the formation of aberrant crypt foci (ACF), hemolysate antioxidant enzyme activities, colonic mucosal antioxidant enzyme gene expression, and colonic mucosal inflammatory mediator gene expression. The feeding of yam prior to carcinogenesis significantly inhibited AOM-induced colonic ACF formation. In yam-administered rats, erythrocyte levels of glutathione, glutathione peroxidase (GPx), and catalase were increased and colonic mucosal gene expression of Cu/Zn-superoxide dismutase (SOD), Mn-SOD, and GPx were up-regulated compared to the AOM group. Colonic mucosal gene expression of inflammatory mediators (i.e., nuclear factor kappaB, inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor alpha, and interleukin-1beta) was suppressed by the yam-supplemented diet. These results suggest that yam could be very useful for the prevention of colon cancer, as they enhance the antioxidant defense system and modulate inflammatory mediators.

20.
Ann Dermatol ; 26(2): 156-61, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24882968

RESUMEN

BACKGROUND: Treatments including intralesional corticosteroid injection, pressure therapy, cryotherapy, and various laser therapies have had limited success for keloids and hypertrophic scars. OBJECTIVE: This trial evaluated the efficacy of a combination of 578 nm copper bromide laser and the more traditional intralesional corticosteroid injection for the treatment of keloids and hypertrophic scars with respect to scar color. METHODS: Keloids or hypertrophic scars of 12 Korean patients were treated five times by the combined treatment at 4-week intervals. Clinical improvement was assessed by the physicians' global assessment (PGA) comparing pre- and post-treatment photographs, as well as 4 weeks after the last treatment. Erythema intensity was quantified using a mexameter. RESULTS: Most scars showed significant clinical improvement in PGA and decreased erythema intensity after 5 treatments. All patients showed improvements in symptoms like pruritus. CONCLUSION: The combined treatment is effective for keloids and hypertrophic scars, especially when the telangiectatic portion of the scars is prominent. The adjunctive use of 578 nm copper bromide laser decreased the telangiectatic side effects of an intralesional corticosteroid injection by reducing the vascular components of scars.

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