Very long-lasting spinal anesthesia with dexmedetomidine: A report of two cases.

Spinal anesthesia usually lasts up to two hours, but an infusion of IV dexmedetomidine can prolong it to three to four hours. We report two cases where single spinal anesthesia with IV dexmedetomidine was maintained for more than six hours during tibia fracture surgery. The spinal anesthesia was maintained for 350 and 390 minutes without another medication, and the sensory level confirmed after the surgery was T10 and L1. Dexmedetomidine can very-prolong the duration of spinal anesthesia beyond what has been reported. However, longer infusion times can also result in longer recovery times.

Feasibility of free-breathing dynamic contrast-enhanced MRI of the abdomen: a comparison between CAIPIRINHA-VIBE, Radial-VIBE with KWIC reconstruction and conventional VIBE.

OBJECTIVE: To evaluate the feasibilities of controlled aliasing in parallel imaging results in higher acceleration with volumetric interpolated breath-hold examination (CAIPIRINHA-VIBE), radial acquisition of VIBE (Radial-VIBE) with k-space-weighted image contrast (KWIC) reconstruction (KWIC-Radial-VIBE) and conventional-VIBE (c-VIBE) for free-breathing dynamic contrast-enhanced (DCE)-MRI of the abdomen. METHODS: 23 prospectively enrolled patients underwent DCE-MRI of the abdomen with CAIPIRINHA-VIBE (n = 10), KWIC-Radial-VIBE (n = 6) or c-VIBE (n = 7). Qualitative image quality of the DCE-MR images and perfusion maps was independently scored by two abdominal radiologists using a 5-point scale (from 1, uninterpretable, to 5, very good). For quantitative analysis, the signal-to-noise ratio (SNR) of the liver and goodness-of-fit (GOF) of the time-intensity curve were measured. RESULTS: In the three tested sequences, DCE-MRI had good temporal (5 s) and spatial resolution (1.48 × 1.48 × 4 mm/voxel). Interobserver agreement in the qualitative analysis was good (ĸ = 0.753; 95% confidence interval, 0.610-0.895). Therefore, the mean scores were used in the data analysis. Overall image quality was comparable between CAIPIRINHA-VIBE (3.52 ± 0.55) and KWIC-Radial-VIBE (3.72 ± 0.37; p = 1.000), and both were significantly better than c-VIBE (2.71 ± 0.34; p < 0.001). Perfusion map quality score was highest with KWIC-Radial-VIBE (4.33 ± 0.65), followed by CAIPIRINHA-VIBE (3.70 ± 0.73) and c-VIBE (3.14 ± 0.66), but without statistical significance between CAIPIRINHA-VIBE and KWIC-Radial-VIBE (p = 0.167). The SNR of the liver and GOF of the time-intensity curve did not significantly differ between the three sequences (p = 0.116 and 0.224, respectively). CONCLUSION: CAIPIRINHA-VIBE and KWIC-Radial-VIBE provide comparably better performance than c-VIBE. Both can be feasible sequences with acceptable good image quality for free-breathing DCE-MRI. ADVANCES IN KNOWLEDGE: CAIPIRINHA-VIBE and KWIC-Radial-VIBE provide comparably better quality of free-breathing DCE-MRIs than c-VIBE.

Relationship between adipokines and manifestations of childhood asthma.

Although the prevalences of asthma and obesity are increasing substantially in recent decades, very little is known about the possible association between them. We evaluated the roles of leptin, adiponectin, and resistin, which are adipokines produced by adipose tissue, on childhood asthma, and their association with pulmonary function and bronchial hyperresponsiveness. We studied 149 atopic asthmatic children, 37 non-atopic asthmatic children, and 54 healthy children. Body mass index was calculated using height and weight, which were measured on the same day that pulmonary function tests and methacholine challenge tests were performed. Skin prick tests were performed, and total eosinophil count, total serum immunoglobulin E (IgE), serum eosinophil cationic protein, leptin, adiponectin, and resistin were measured in all subjects. Atopic asthmatics had lower resistin levels compared with non-atopic asthma and control groups, but leptin and adiponectin did not show any difference among these three groups. Resistin demonstrated positive correlation with methacholine PC(20) and negative correlations with eosinophil count and serum total IgE. Leptin and adiponectin showed associations with forced expiratory volume in 1 s or forced expiratory flow between 25-75%. Multiple regression analysis revealed that resistin was a significant predictive factor for asthma. There was no direct association between asthma and leptin or adiponectin. Our findings suggest that resistin may play a negative predictive role in asthma. Adiponectin and leptin showed close associations with pulmonary function and may have disease-modifying effects in children with asthma.

Summer time haze characteristics of the urban atmosphere of Gwangju and the rural atmosphere of Anmyon, Korea.

An extensive visibility monitoring was carried out simultaneously in the urban area of Gwangju and the rural area of Anmyon, Korea. This study examines patterns of visibility impairment and haze-forming pollutant concentrations on both sites resulting from natural and anthropogenic sources of gases and particles. Optical visibility measurements by a transmissometer, a nephelometer and an aethalometer provide aerosol light extinction, scattering, and absorption coefficients for both sites. In order to investigate the physico-chemical characteristics of atmospheric aerosols, aerosol samples were collected by various aerosol samplers at GJVMS (Gwangju Visibility Monitoring Station) and at KGAWO (Korea Global Atmosphere Watch Observatory), respectively. In addition, haze characteristics causing visibility impairment at those two sites were analyzed to obtain source contributions by regionally transported aerosols using grid analysis and display system (GrADS) from NECP reanalysis data. During the intensive monitoring period, ammonium sulfate was dominantly responsible for the fine particle mass loading at GJVMS, whereas organic carbon was the largest contributor at KGAWO. Light scattering by particles accounted for 52.8 to 81.3% of the range at the urban site, GJVMS and for 72.1 to 94.2% of the range at the rural site, KGAWO. Light absorption by the EC and NO2 was between 14.5 and 34.8% at GJVMS, which was higher than the observed 1.1 approximately 6.8% at KGAWO, respectively. Light scattering by aerosol was higher in the rural area than in the urban area. And organic carbon concentration was observed to be significantly higher than the concentration of elemental carbon at KGAWO. These haze-forming carbonaceous particles originate from anthropogenic pollutants at the urban atmosphere but they can be produced by natural environments such as marine and forest at the rural atmosphere.

Antimicrobial activity of native chitosan, degraded chitosan, and O-carboxymethylated chitosan.

The antimicrobial activity of native chitosan was compared to that of lipase-degraded chitosan. The effects of O-carboxymethylated (O-CM) substitution on native (molecular weight, 120; degree of deacetylation, 84.71%) and lipase-degraded chitosans were also investigated. The antimicrobial activity of native chitosan was more extensive than that of lipase-degraded chitosan; however, lipase-degraded chitosan was still highly effective and more water-soluble. O-CM chitosan derived from degraded chitosan was more effective than O-CM chitosan derived from native chitosan. O-CM substitution enhanced lipase-degraded chitosan's antimicrobial activity without reducing its solubility.