RESUMEN
The high spatial frequency periodic structures induced on metal surface by femtosecond laser pulses was investigated experimentally and numerically. It is suggested that the redistribution of the electric field on metal surface caused by the initially formed low spatial frequency periodic structures plays a crucial role in the creation of high spatial frequency periodic structures. The field intensity which is initially localized in the grooves becomes concentrated on the ridges in between the grooves when the depth of the grooves exceeds a critical value, leading to the ablation of the ridges in between the grooves and the formation of high spatial frequency periodic structures. The proposed formation process is supported by both the numerical simulations based on the finite-difference time-domain technique and the experimental results obtained on some metals such as stainless steel and nickel.
Asunto(s)
Rayos Láser , Materiales Manufacturados , Níquel/química , Acero Inoxidable/química , Simulación por Computador , Análisis de Elementos Finitos , Microscopía Electrónica de Rastreo , Análisis Numérico Asistido por ComputadorRESUMEN
(-)-Menthol ([1-alpha]-5-methyl-2-[1-methylethyl]-cyclohexanol), is a widely used flavoring ingredient in mouthwash, foods, toothpaste and cigarettes. The studies reported here revealed that (-)-menthol induced cytotoxicity against murine leukemia WEHI-3 cells in vitro in a dose-dependent manner. The effects of (-)-menthol on WEHI-3 cells in vivo (BALBIc mice) were also examined, and it was observed that the Mac-3 and CD11b markers were decreased, indicating inhibition of differentiation of the precursor of macrophage and granulocyte. The weights of liver and spleen samples from mice treated with (-)-menthol were found to be decreased compared to untreated animals.
Asunto(s)
Leucemia Experimental/tratamiento farmacológico , Leucemia Experimental/patología , Mentol/uso terapéutico , Animales , Peso Corporal/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Leucemia Mielomonocítica Aguda/sangre , Leucemia Mielomonocítica Aguda/tratamiento farmacológico , Leucemia Mielomonocítica Aguda/patología , Hígado/efectos de los fármacos , Hígado/patología , Mentol/sangre , Mentol/farmacocinética , Mentol/farmacología , Ratones , Ratones Endogámicos BALB C , Bazo/efectos de los fármacos , Bazo/patologíaRESUMEN
Acute traumatic peripheral nerve injury remains a significant clinical issue affecting mostly young individuals and their productivity in spite of advances in current medicine. Hyaluronan has been explored in this scenario for its anti-adhesive and high biocompatibility properties for decades. The molecular weight and concentration of the locally applied hyaluronan has been overlooked and not optimized. We used different molecular weights and concentrations of hyaluronan in a rat sciatic nerve crush injury model and found better overall outcomes with high molecular weight (3000 kDa) hyaluronan. The anti-inflammatory effect of the higher molecular weight hyaluronan may have a more favorable effect. We conclude that the optimization of hyaluronan is necessary when incorporating hyaluronan in the engineering of biomaterials for use in acute traumatic peripheral nerve injury.
Asunto(s)
Ácido Hialurónico/administración & dosificación , Traumatismos de los Nervios Periféricos/tratamiento farmacológico , Nervio Ciático/efectos de los fármacos , Nervio Ciático/lesiones , Neuropatía Ciática/tratamiento farmacológico , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/química , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/química , Bioingeniería , Modelos Animales de Enfermedad , Potenciales Evocados Somatosensoriales/efectos de los fármacos , Humanos , Ácido Hialurónico/química , Masculino , Ensayo de Materiales , Peso Molecular , Regeneración Nerviosa/efectos de los fármacos , Regeneración Nerviosa/fisiología , Traumatismos de los Nervios Periféricos/patología , Traumatismos de los Nervios Periféricos/fisiopatología , Ratas , Ratas Sprague-Dawley , Nervio Ciático/fisiopatología , Neuropatía Ciática/patología , Neuropatía Ciática/fisiopatologíaRESUMEN
Giant cell arteritis (GCA) often presents with symptoms of headache, jaw claudication, polymyalgia rheumatica, and blurred vision. GCA is relatively rare and may have atypical manifestations in Asians, including multiple cranial nerve palsy and reversible proptosis. A high suspicion of GCA is suggested when any older Asian suffers from headache that is new-onset or different from the previous pattern, even without other typical manifestations of GCA.