The fluorescent microspheres are prepared by the swelling-evaporation method. The optimal swelling conditions are obtained by researching related factors, such as types and dosages of swelling agent, dosages of fluorescent substance, swelling time and swelling temperature. Considering that the structure of microspheres can influence the swelling properties, the paper mainly focuses on the effect of molecular weight and surface carboxyl group content of polystyrene microspheres on swelling properties. When the molecular weight of microspheres is 75276 g mol-1, the density of carboxyl group on their surface is 6.94×10-4 mol g-1, and the doping amount of europium complex reaches the maximum of 24.9 mg g-1 with the strongest fluorescence intensity. Meanwhile, the as-prepared fluorescent microspheres have high monodispersity, uniform particles size and high thermal stability (the decomposition temperature is 385oC), which sets up the good foundation for biomolecule detection. So, this work provides a significant experience for the preparation of fluorescent microspheres.

Abstract Objectives: Depression is common after both lacunar stroke and non-lacunar stroke and might be associated with lesion locations as proven by some studies. This study aimed to identify whether lesion location was critical for depression after both lacunar and non-lacunar strokes. Methods: A cohort of ischemic stroke patients was assigned to either a lacunar stroke group or a non-lacunar stroke group after a brain MRI scan. Neurological deficits and treatment response was evaluated during hospitalization. The occurrence of depression was evaluated 3 months later. Logistic regressions were used to identify the independent risk factors for depression after lacunar and non-lacunar stroke respectively. Results: 83 of 246 patients with lacunar stroke and 71 of 185 patients with non-lacunar stroke developed depression. Infarctions in the frontal cortex, severe neurological deficits, and a high degree of handicap were identified as the independent risk factors for depression after non-lacunar stroke, while lesion location was not associated with depression after lacunar stroke. Conclusion: The main determinants for depression after lacunar and non-lacunar stroke were different. Lesion location was critical only for depression after non-lacunar stroke.

Flower - like Co(OH)2/C nanocomposites have been synthesized by a facile hydrothermal method. Flower - like Co(OH)2/C nanocomposites were self - assembled by the nanosheets with the thickness distribution of 50 - 80 nm and abundant flocculent carbon structures. With the help of transmission electron microscopy and energy dispersive spectrometer, nanosheets were observed to have core/shell structure, in which Co(OH)2 worked as cores and amorphous C as shells. When the as - prepared products were heated for 6 h at 180 ºC, the Co(OH)2 cores were amorphous. The heating time increased to 10 h, the Co(OH)2 cores became crystalline. The formation mechanism and the self - assembly evolution process were proposed. The microwave dielectric properties of Co(OH)2/C nanocomposites were investigated in the frequency range of 0.03 - 18 GHz. Compared with the amorphous Co(OH)2/C nanocomposites, crystalline nanocomposites had the better conductivity.

The microstructure and microwave absorption of carbon-coated Cu nanocapsules have been investigated. Carbon-coated Cu nanocapsules have been synthesized by an arc-discharge method. The paraffin-Cu/C nanocapsules composite shows excellent electromagnetic (EM) absorption properties. An optimal reflection loss (RL) value of - 40.0 dB is reached at 10.52 GHz for a layer 1.9 mm thickness. RL exceeding - 20 dB can be realized in any interval within the 1-18 GHz range by choosing an appropriate thickness of the absorbent layer between 1.1 and 10.0 mm. Theoretical simulation for the microwave absorption using the transmission line theory agrees reasonably well with the experimental results. The EM-wave absorption properties of nanocapsules materials are illustrated by means of an absorption-tube-map. The carbon-coated Cu nanocapsule is an attractive candidate for EM-wave absorption, which significantly enriches the family of EM-wave nanoabsorbents.

A facile hydrothermal strategy is proposed to synthesize flower-like β-Co(OH)2 hierarchical microspherical superstructures with a diameter of 0.5-1.5 μm, which are self-assembled by β-Co(OH)2 nanosheets with the average thickness ranging between 20 and 40 nm. The magnetocaloric effect associated with magnetic phase transitions in Co(OH)2 superstructures has been investigated. A sign change in the magnetocaloric effect is induced by a magnetic field, which is related to a filed-induced transition from the antiferromagnetic to the ferromagnetic state below the Néel temperature. The large reversible magnetic-entropy change -ΔSm (13.4 J/kg K at 15 K for a field change of 5 T) indicates that flower-like Co(OH)2 superstructures is a potential candidate for application in magnetic refrigeration in the low-temperature range.

Objetivo Estudar as diferentes formas dos infartos lacunares agudos, investigando os fatores de risco e o significado clinico daqueles com morfologia irregular. Métodos Os 204 pacientes com infartos lacunares agudos foram classificados em dois grupos: aqueles com morfologia regular e aqueles com morfologia irregular. Foram estudadas as características dos dois grupos e caracterizados os fatores de risco para infartos irregulares, deterioração neurológica e altos escores da escala de Rankin modificada. Resultados Variabilidade da pressão arterial é fator de risco independente para infartos lacunares irregulares. Tamanho do infarto, prevalência de leucoaraiose e formato irregular dos infartos lacunares são fatores de risco independentes para escores mais elevados na escala de Rankin modificada. Conclusões Variabilidade da pressão arterial está relacionada ao formato irregular dos infartos lacunares agudos. Este tipo de infarto e a leucoaraiose podem estar relacionado a desfechos clínicos desfavoráveis.

Objective Our study focused on acute lacunar infarct shapes to explore the risk factors and clinical significance of irregularly shaped lacunar infarctions. Methods Based on the shape of their acute lacunar infarct, patients (n=204) were classified into the “regular” group or “irregular” group. The characteristics of the lacunar infarction were compared between the regular and irregular groups, between patients with and without neurological deterioration, and between patients with different modified Rankin scale (mRS) scores. The risk factors for irregularly shaped lacunar infarctions, neurological deterioration, and high mRS scores were identified. Results Blood pressure variability (BPV) was an independent risk factor for irregularly shaped lacunar infarction. Infarction size, prevalence of advanced leukoaraiosis, and irregularly shaped lacunar infarcts were independent risk factors for higher mRS scores. Conclusions The irregularly shaped lacunar infarcts were correlated with BPV. Irregularly shaped lacunar infarctions and leukoaraiosis may be associated with unfavorable clinical outcomes.

OBJECTIVE: Silent brain infarctions are the silent cerebrovascular events that are distinguished from symptomatic lacunar infarctions by their 'silence'; the origin of these infarctions is still unclear. This study analyzed the characteristics of silent and symptomatic lacunar infarctions and sought to explore the mechanism of this 'silence'. METHODS: In total, 156 patients with only silent brain infarctions, 90 with only symptomatic lacunar infarctions, 160 with both silent and symptomatic lacunar infarctions, and 115 without any infarctions were recruited. Vascular risk factors, leukoaraiosis, and vascular assessment results were compared. The National Institutes of Health Stroke Scale scores were compared between patients with only symptomatic lacunar infarctions and patients with two types of infarctions. The locations of all of the infarctions were evaluated. The evolution of the two types of infarctions was retrospectively studied by comparing the infarcts on the magnetic resonance images of 63 patients obtained at different times. RESULTS: The main risk factors for silent brain infarctions were hypertension, age, and advanced leukoaraiosis; the main factors for symptomatic lacunar infarctions were hypertension, atrial fibrillation, and atherosclerosis of relevant arteries. The neurological deficits of patients with only symptomatic lacunar infarctions were more severe than those of patients with both types of infarctions. More silent brain infarctions were located in the corona radiata and basal ganglia; these locations were different from those of the symptomatic lacunar infarctions. The initial sizes of the symptomatic lacunar infarctions were larger than the silent brain infarctions, whereas the final sizes were almost equal between the two groups. CONCLUSIONS: Chronic ischemic preconditioning and nonstrategic locations may be the main reasons for the 'silence' of silent brain infarctions.

Foi desenvolvido um método simples, sensível e rápido de extração em fase sólida utilizando cromatografia liquida de alta eficiência (SPE-CLAE) para a determinação simultânea de quatro cumarinas, psoralen, isopsoralen, imperatorina e isoimperatorina, utilizando ostole como padrão interno. Utilizando este método, foi analisada a farmacocinética destas cumarinas em plasma de ratos após administração oral de uma cápsula "YIGONG" da medicina chinesa tradicional. Amostras de plasma foram pré-tratadas com extração em fase sólida utilizando cartuchos Extract-CleanTM e a separação dos extratos foi realizada com uma coluna Eurospher C18 utilizando metanol-água como fase móvel. Os limites de quantificação foram 9,7 ng mL-1 para psoralen, 7,1 ng mL-1 para isopsoralen, 6,7 ng mL-1 para imperatorina e 3,0 ng mL-1 para isoimperatorina. As recuperações médias das quatro cumarinas contidas no plasma de ratos foram bem acima de 80%. As precisões determinadas para 6 dias estiveram sempre dentro de 10%. Concluiu-se que o método estabelecido é adequado para estudos farmacocinéticos destas quatro cumarinas em plasma de ratos.

A simple, sensitive and rapid solid-phase extraction method by using high performance liquid chromatography (SPE-HPLC) was developed for simultaneous determination of four coumarins, psoralen, isopsoralen, imperatorin and isoimperatorin using osthole as internal standard. Using this method, pharmacokinetic of these coumarins in rat plasma was analyzed after oral administration of a traditional Chinese medicine "YIGONG" capsule. Plasma samples were pretreated with solid-phase extraction using Extract-CleanTM cartridges, and separation of the extracts was performed on a Eurospher C18 column using methanol-water as mobile phase. The quantification limits for psoralen, isopsoralen, imperatorin and isoimperatorin in rat plasma were 9.7, 7.1, 6.7 and 3.0 ng mL-1, respectively. Average extract recoveries of the four coumarins from rat plasma were all over 80%. Precisions determined from 6 days were all within 10%. It was concluded that the established method is suitable for pharmacokinetic studies of these four coumarins in rat plasma.