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1.
Ann Plast Surg ; 92(6): 711-719, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38725109

RESUMEN

BACKGROUND: Nevus sebaceous (NS) is a rare congenital skin lesion affecting approximately 0.3% of all newborns. Although benign, NS lesions can harbor malignant secondary tumors. The published rate of development of these malignant tumors varies. This meta-analysis aimed to identify the rate of malignant and benign secondary neoplasms occurring in NS. METHODS: A literature search was conducted using PubMed, Embase, and Web of Science from inception to April 2023. Eligible studies reported incidence or risk of secondary neoplasms in patients with NS. Two independent reviewers screened studies, extracted data, and assessed the quality of included studies. The primary outcome was the pooled incidence of secondary neoplasms. Studies with sample sizes greater than 50 patients were eligible for meta-analysis using the random-effects model. RESULTS: Twenty-eight studies were identified, 22 of which were eligible for meta-analysis. The overall rate of secondary neoplasms was 12.8% (95% confidence interval [Cl], 9.2%-17.6%). The rates of development of malignant and benign tumors were 2.4% (95% CI, 1.4%-4.1%) and 10.3% (95% CI, 7.5%-13.9%), respectively. The rate of development of basal cell carcinoma was 1.7% (95% CI, 0.9%-3.2%), whereas the rate of the development of syringocystadenoma papilliferum was 3.6% (95% CI, 2.5%-5.3%) and that if trichoblastoma was 2.6% (95% CI, 1.7%-3.8%). CONCLUSIONS: Although the rate of development of malignant tumors within a primary NS lesion is low, it is not negligible. Prophylactic early excision remains a viable approach to prevent secondary malignant neoplasms, address cosmetic and functional complications, and preempt the need for complex reconstruction in the future. We propose that resection of NS lesions in childhood remains a reasonable first-line option in the appropriate patient keeping in mind that it may leave an undesirable scar.


Asunto(s)
Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Incidencia , Neoplasias Primarias Secundarias/patología , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/cirugía , Nevo Sebáceo de Jadassohn/cirugía , Nevo Sebáceo de Jadassohn/patología , Nevo/cirugía , Nevo/patología
2.
Heliyon ; 10(9): e29976, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38765107

RESUMEN

Sinomenine (SIN), an alkaloid derived from the traditional Chinese medicine, Caulis Sinomenii, has been used as an anti-inflammatory drug in China for over 30 years. With the continuous increase in research on the pharmacological mechanism of SIN, it has been found that, in addition to the typical rheumatoid arthritis (RA) treatment, SIN can be used as a potentially effective therapeutic drug for anti-tumour, anti-renal, and anti-nervous system diseases. By reviewing a large amount of literature and conducting a summary analysis of the literature pertaining to the pharmacological mechanism of SIN, we completed a review that focused on SIN, found that the current research is insufficient, and offered an outlook for future SIN development. We hope that this review will increase the public understanding of the pharmacological mechanisms of SIN, discover SIN research trial shortcomings, and promote the effective treatment of immune diseases, inflammation, and other related diseases.

3.
JTO Clin Res Rep ; 5(2): 100633, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38371193

RESUMEN

Introduction: Physical activity (PA) is a potentially modifiable risk factor for lung cancer, with previous research revealing that people who engage in more PA have lower risk of developing lung cancer. PA levels of lung cancer screening participants have not previously been explored. Methods: Participants at a single Australian International Lung Screen Trial site were eligible for assessment of self-reported PA levels (International Physical Activity Questionnaire and Physical Activity Scale for the Elderly) and physical assessments (6-min walk distance, hand grip muscle strength, daily step count, and body composition) at a single time point during lung cancer screening. Statistics were predominantly descriptive, with parametric data presented as mean and SD and nonparametric data presented as median and interquartile range (IQR). Results: A total of 178 participants were enrolled in this study, with a median age of 61 years. Of the participants, 61% were men and 51% were people who currently smoke. The median total International Physical Activity Questionnaire score was 1756 MET/min/wk (IQR 689, 4049). Mean total Physical Activity Scale for the Elderly score was 160 (SD 72), higher than described in healthy sedentary adults. The median daily step count was 7237 steps (IQR 5353, 10,038) and mean 6-minute walk distance was 545 m (SD 92). Median grip strengths were within predicted normal range, with an elevated median percentage body fat and low skeletal muscle mass found on body composition. Conclusion: Almost a quarter of International Lung Screen Trial participants assessed reported low levels of PA and have a potentially modifiable risk factor to improve health outcomes. Larger studies are needed to characterize the burden of inactivity among high-risk lung cancer screening populations.

4.
Health Qual Life Outcomes ; 22(1): 10, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273370

RESUMEN

BACKGROUND: Evaluation of psychosocial consequences of lung cancer screening with LDCT in high-risk populations has generally been performed using generic psychometric instruments. Such generic instruments have low coverage and low power to detect screening impacts. This study aims to validate an established lung cancer screening-specific questionnaire, Consequences Of Screening Lung Cancer (COS-LC), in Australian-English and describe early results from the baseline LDCT round of the International Lung Screen Trial (ILST). METHODS: The Danish-version COS-LC was translated to Australian-English using the double panel method and field tested in Australian-ILST participants to examine content validity. A random sample of 200 participants were used to assess construct validity using Rasch item response theory models. Reliability was assessed using classical test theory. The COS-LC was administered to ILST participants at prespecified timepoints including at enrolment, dependent of screening results. RESULTS: Minor linguistic alterations were made after initial translation of COS-LC to English. The COS-LC demonstrated good content validity and adequate construct validity using psychometric analysis. The four core scales fit the Rasch model, with only minor issues in five non-core scales which resolved with modification. 1129 Australian-ILST participants were included in the analysis, with minimal psychosocial impact observed shortly after baseline LDCT results. CONCLUSION: COS-LC is the first lung cancer screening-specific questionnaire to be validated in Australia and has demonstrated excellent psychometric properties. Early results did not demonstrate significant psychosocial impacts of screening. Longer-term follow-up is awaited and will be particularly pertinent given the announcement of an Australian National Lung Cancer Screening Program. TRIAL REGISTRATION: NCT02871856.


Asunto(s)
Neoplasias Pulmonares , Humanos , Australia , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/psicología , Pulmón , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/psicología , Calidad de Vida , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
5.
Neural Regen Res ; 19(5): 1013-1019, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37862203

RESUMEN

Spinal cord organoids are three-dimensional tissues derived from stem cells that recapitulate the primary morphological and functional characteristics of the spinal cord in vivo. As emerging bioengineering methods have led to the optimization of cell culture protocols, spinal cord organoids technology has made remarkable advancements in the past decade. Our literature search found that current spinal cord organoids do not only dynamically simulate neural tube formation but also exhibit diverse cytoarchitecture along the dorsal-ventral and rostral-caudal axes. Moreover, fused organoids that integrate motor neurons and other regionally specific organoids exhibit intricate neural circuits that allows for functional assessment. These qualities make spinal cord organoids valuable tools for disease modeling, drug screening, and tissue regeneration. By utilizing this emergent technology, researchers have made significant progress in investigating the pathogenesis and potential therapeutic targets of spinal cord diseases. However, at present, spinal cord organoid technology remains in its infancy and has not been widely applied in translational medicine. Establishment of the next generation of spinal cord organoids will depend on good manufacturing practice standards and needs to focus on diverse cell phenotypes and electrophysiological functionality evaluation.

6.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38065188

RESUMEN

Reference point indentation (RPI) is a novel experimental technique designed to evaluate bone quality. This study utilizes two RPI instruments, BioDent and Osteoprobe, to investigate the mechanical responses of several 3D-printed polymers. We correlated the mechanical properties from a tensile test with the RPI parameters obtained from the BioDent and OsteoProbe. In addition, we tested the same polymers five years later (Age 5). The results show that for Age 0 polymers, the elastic modulus is highly correlated with average unloading slope (r = 0.87), first unloading slope (r = 0.85), bone material strength index (BMSi) (r = 0.85), average loading slope (r = 0.82), first indentation distance (r = 0.79), and total indentation distance (r = 0.76). The ultimate stress correlates significantly with first unloading slope (r = 0.85), average unloading slope (r = 0.83), BMSi (r = 0.81), first indentation distance (r = 0.73), average loading slope (r = 0.71), and total indentation distance (r = 0.70). The elongation has no significant correlation with the RPI parameters except with the average creep indentation distance (r = 0.60). For Age 5 polymers, correlations between mechanical properties and RPI parameters are low. This study illustrates the potential of RPI to assess the mechanical properties of polymers nondestructively with simple sample requirements. Furthermore, for the first time, 3D-printed polymers and aged polymers are investigated with RPI.

7.
Sci Rep ; 11(1): 7012, 2021 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-33782429

RESUMEN

Bone is a biological composite material consisting of two main components: collagen and mineral. Collagen is the most abundant protein in vertebrates, which makes it of high clinical and scientific interest. In this paper, we compare the composition and structure of cortical bone demineralized using several protocols: ethylene-diamine-tetraacetic acid (EDTA), formic acid (CH2O2), hydrochloric acid (HCl), and HCl/EDTA mixture. The efficiencies of these four agents were investigated by assessing the remaining mineral quantities and collagen integrity with various experimental techniques. Raman spectroscopy results show that the bone demineralized by the CH2O2 agent has highest collagen quality parameter. The HCl/EDTA mixture removes the most mineral, but it affects the collagen secondary structure as amide II bands are shifted as observed by Fourier transform infrared spectroscopy. Thermogravimetric analysis reveals that HCl and EDTA are most effective in removing the mineral with bulk measurements. In summary, we conclude that HCl best demineralizes bone, leaving the well-preserved collagen structure in the shortest time. These findings guide on the best demineralization protocol to obtain high-quality collagen from bone for clinical and scientific applications.


Asunto(s)
Técnica de Desmineralización de Huesos/clasificación , Técnica de Desmineralización de Huesos/métodos , Colágeno/química , Hueso Cortical/metabolismo , Animales , Porcinos
8.
J Mech Behav Biomed Mater ; 113: 104132, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33049620

RESUMEN

Bone is a composite material consisting principally of apatite mineral, collagen fibrils, non-collagenous proteins, and other organic species. Recent electron microscopy studies have shown that the mineral in bone occurs as stacks of thin polycrystalline sheets ("mineral lamellae," MLs) which surround and lie between the collagen fibrils. We focus on the effect of the interface between these mineral lamellae on the mechanical properties of bone. Previous studies on bone treated with sodium hypochlorite (NaClO) to remove all organic material showed a greatly weakened mineral framework. Here, we treated femoral cortical bone with ethylenediamine (EDA), which only removes collagen, to study the effect of its removal on bone properties. We tested the degree of completion of the treatment by Raman spectroscopy and thermogravimetric analysis. When only collagen is removed, a continuous mineral structure remains and is less weakened than by NaClO treatment. Transmission electron microscopy study of finely ground particles of the EDA treated bone shows that stacks of MLs remain joined, whereas in NaClO treated bone, only isolated crystals are present. Thus, we infer that the MLs in bone are held together in stacks by an organic glue, which is destroyed by NaClO, but which survives the EDA treatment. We show that this glue may contribute to the stiffness, strength, and energy absorption of bone. Further studies are needed to discover the chemical nature of this glue. This study provides a starting point for such investigations.


Asunto(s)
Huesos , Minerales , Apatitas , Hueso Cortical , Microscopía Electrónica de Transmisión
9.
Med Eng Phys ; 84: 60-67, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32977923

RESUMEN

Titanium implants are widely used in dental and orthopedic surgeries. Osseointegration phenomena lead to direct contact between bone tissue and the implant surface. The quality of the bone-implant interface (BII), resulting from the properties of newly formed bone, determines the implant stability. This study investigates the BII properties using a dedicated in vivo implant model consisting of a coin-shaped Ti-6Al-4V implant inserted in a rabbit femur for 10 weeks. A gap created below the implant was filled with newly formed bone tissue after healing. The properties of mature and newly formed bone tissues were compared using: i) Raman spectroscopy to assess the nanoscale compositional bone properties and ii) nanoindentation to quantify microscale elastic properties in site-matched regions. The mineral-to-matrix ratio, crystallinity (mineral size and lattice order), and the collagen cross-link ratio were significantly lower in newly formed bone tissue (e.g., a mineral-to-matrix ratio of 9.3 ± 0.5 for proline 853 cm-1) compared to mature bone (15.6 ± 1). Nanoindentation measurements gave Young's modulus of 12.8 ± 1.8 GPa for newly formed bone and 15.7 ± 2.3 GPa for mature bone. This multimodal and multiscale approach leads to a better understanding of osseointegration phenomena.


Asunto(s)
Interfase Hueso-Implante , Implantes Dentales , Animales , Oseointegración , Conejos , Espectrometría Raman , Propiedades de Superficie , Titanio
10.
Soft Matter ; 16(6): 1389-1403, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31939988

RESUMEN

The current trend in the global advanced material market is expeditiously shifting towards more lightweight, multifunctional configurations, considering very recent developments in electrical aircraft, biomedical devices, and autonomous automobiles. Hence, the development of novel polymer nanocomposite materials is critical to advancing the current state-of-the-art of structural material technologies to address the pressing performance demands. Aiming at expanding the existing material design space, we have investigated crosslinkable aromatic polyester matrix nanocomposites. Aromatic polyesters, in the thermosetting form, are a prospective high-performance/high-temperature polymer technology, which is on a par with conventional epoxy-derivative resins and high-performance engineering thermoplastics in the range of their potential applications. The aromatic matrix-based thermosetting nanocomposites manifest greatly enhanced physical properties enabled by a chemistry-favored robust interfacial covalent coupling mechanism developed during the in situ polymerization reaction with various nanofiller particle configurations. Here, we provide a summary review of our recent efforts in developing this novel polymer nanocomposite material system. We highlight the chemical strategy, fabrication approach, and processing techniques developed to obtain various nanocomposite representations for structural, electrical, optical, biomedical, and tribological applications. The unique characteristic features emerging in the nanocomposite morphologies, along with their physicochemical effects on the multifunctional macroscale properties, are demonstrated. This unique matrix configuration introduces superior performance elements to polymer nanocomposite applications towards designing advanced composite materials.

11.
Appl Opt ; 57(22): 6491-6495, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30117887

RESUMEN

We report the first demonstration, to the best of our knowledge, of tunable and Q-switched lasers based on diode-pumped Nd,Lu:CaF2 disordered crystal. A continuous tuning range of approximately 32 nm (1047-1079 nm) was obtained for tunable operations. A passively Q-switched laser was successfully achieved using a Cr4+:YAG as a saturable absorber. The shortest pulse width of 275 ns was obtained with a repetition rate of 1.85 kHz and corresponding peak power and single pulse energy of 189 W and 51.9 µJ, respectively.

12.
Calcif Tissue Int ; 103(5): 554-566, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30022228

RESUMEN

Bone is a biological composite material having collagen and mineral as its main constituents. In order to better understand the arrangement of the mineral phase in bone, porcine cortical bone was deproteinized using different chemical treatments. This study aims to determine the best method to remove the protein constituent while preserving the mineral component. Chemicals used were H2O2, NaOCl, NaOH, and KOH, and the efficacy of deproteinization treatments was determined by thermogravimetric analysis and Raman spectroscopy. The structure of the residual mineral parts was examined using scanning electron microscopy. X-ray diffraction was used to confirm that the mineral component was not altered by the chemical treatments. NaOCl was found to be the most effective method for deproteinization and the mineral phase was self-standing, supporting the hypothesis that bone is an interpenetrating composite. Thermogravimetric analyses and Raman spectroscopy results showed the preservation of mineral crystallinity and presence of residual organic material after all chemical treatments. A defatting step, which has not previously been used in conjunction with deproteinization to isolate the mineral phase, was also used. Finally, Raman spectroscopy demonstrated that the inclusion of a defatting procedure resulted in the removal of some but not all residual protein in the bone.


Asunto(s)
Hueso Cortical/ultraestructura , Técnicas de Preparación Histocitológica/métodos , Minerales/análisis , Animales , Microscopía Electrónica de Rastreo , Espectrometría Raman , Porcinos , Difracción de Rayos X
13.
Phys Rev E ; 93(5): 053001, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27300967

RESUMEN

Crack events developed during uniaxial compression of cortical bones cut from femurs of developing pigs of several ages (4, 12, and 20 weeks) generate avalanches. These avalanches have been investigated by acoustic emission analysis techniques. The avalanche energies are power-law distributed over more than four decades. Such behavior indicates the absence of characteristic scales and suggests avalanche criticality. The statistical distributions of energies and waiting times depend on the pig age and indicate that bones become stronger, but less ductile, with increasing age. Crack propagation is equally age-dependent. Older pigs show, on average, larger cracks with a time distribution similar to those of aftershocks in earthquakes, while younger pigs show only statistically independent failure events.

14.
J Alzheimers Dis ; 23(3): 551-61, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21297277

RESUMEN

Amyloid-ß peptide (Aß) is recognized by many as the leading cause of Alzheimer's disease (AD), and Aß oligomers play a major role in the early-onset form of AD. Recently, the application of passive immunization targeting Aß has been investigated as a potential method of AD immunotherapy. We used a strain of monoclonal antibody against Aß42 oligomers, designated A8, as an Aß inhibitor to suppress Aß aggregation and Aß-derived cell toxicity in vitro, and as a passive immunotherapy approach to treat SAMP8 (senescence accelerated mouse sub-line P8) mice, an animal model of AD, in vivo. First, our results showed that pre-incubation of A8 with Aß oligomers inhibited both the maturation of Aß fiber and Aß oligomer toxicity on SH-SY5Y cells. Second, learning and memory was improved through intraperitoneal administration of A8 in SAMP8 mice. Third, Aß pathology was ameliorated with decreased Aß oligomers and phospho-tau levels in SAMP8 mice. Our data suggest that our monoclonal antibody A8 may be a candidate as a potential immunotherapeutic agent in AD.


Asunto(s)
Péptidos beta-Amiloides/inmunología , Anticuerpos Monoclonales/administración & dosificación , Senescencia Celular/efectos de los fármacos , Trastornos de la Memoria/tratamiento farmacológico , Fragmentos de Péptidos/inmunología , Animales , Línea Celular Tumoral , Senescencia Celular/fisiología , Humanos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Aprendizaje por Laberinto/fisiología , Memoria/efectos de los fármacos , Memoria/fisiología , Trastornos de la Memoria/inmunología , Trastornos de la Memoria/patología , Ratones , Ratones Transgénicos
15.
Sheng Wu Gong Cheng Xue Bao ; 25(8): 1195-203, 2009 Aug.
Artículo en Chino | MEDLINE | ID: mdl-19938457

RESUMEN

To get specific scFv (Single-chain fragment variable) antibody against soluble Abeta1-42(Amyloid-beta) oligomers, we constructed a human single-chain Fv (scFv) antibody library by phage display technology. Using RT-PCR, we amplified the variable heavy (VH) and variable light (VL) genes from peripheral blood lymphocytes (PBL). Then we obtained the scFv fragments through SOE-PCR, and the scFv fragments were cloned into the vector pCANTAB5E and electroporated into competent Escherichia coli TG1 cells. Consequently, a scFv phage display library containing 2.5 x 10(9) clones was constructed. The recombinant phagemids were rescued by reinfection of helper phage M13K07. Recombinant phages specific for Abeta1-42 oligomers were enriched after four rounds of biopanning and the antigen-positive clones were selected from the enriched clones by phage ELISA. Positive clone B19 was used to infect E. coli HB2151 to express soluble scFv antibody. SDS-PAGE and Western blotting analysis showed that the soluble scFv B19 antibody was expressed successfully and could bind specifically to Abeta1-42 trimer and protofiber. The specific scFv against Abeta1-42 oligomers can be used in the therapeutic research on Alzheimer's disease.


Asunto(s)
Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/inmunología , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Anticuerpos de Cadena Única/genética , Anticuerpos de Cadena Única/aislamiento & purificación , Especificidad de Anticuerpos/inmunología , Humanos , Biblioteca de Péptidos , Anticuerpos de Cadena Única/inmunología
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