Effects of timolol and acetazolamide on intraocular pressure elevation following argon laser iridotomy.

To study the effect of hypotensive agents on intraocular pressure elevation following argon laser iridotomy, 0.5% timolol maleate topically and acetazolamide 125 mg orally were given in 39 eyes, one hour prior to laser iridotomy, with 29 eyes serving as the control. The mean pressure two hours after laser iridotomy was 18.9 +/- 7.2 mmHg in the control group and 12.8 +/- 3.9 mmHg in the pretreated group. Ocular pressure was elevated from the baseline pressure of the prelaser status in two eyes (5%) only in the timolol-acetazolamide treated group and in 16 eyes (55%) in the control group. The pressure elevation two hours after laser iridotomy was significantly less in the timolol-acetazolamide pretreated group.     

Effect of food on pharmacokinetics of cefuroxime axetil in Chinese subjects.

The effect of food on the pharmacokinetics of cefuroxime axetil was studied. Twelve healthy male subjects were included in this study. They were given single oral 500 mg doses of cefuroxime axetil alone or with food based on a balanced two-way crossover design. Plasma cefuroxime concentrations were assayed by the high performance liquid chromatographic method. When the drug was given alone, the area under the curve (AUC) was 15.77 +/- 4.12 mg*h/L, Cmax was 4.20 +/- 1.05 mg/L, Tmax was 2.36 +/- 0.84 h, T1/2 was 1.56 +/- 0.26 h, and Clp/F was 34.13 +/- 10.39 L/h; 45.12 +/- 9.59% of the dose was recovered in the urine within 24 hours, and the renal clearance was 12.58 +/- 4.41 L/h. When the drug was given with food, the corresponding AUC was 23.46 +/- 4.57 mg*h/L, Cmax was 7.10 +/- 1.41 mg/L, Tmax was 2.04 +/- 1.32 h, T1/2 was 1.40 +/- 0.23 h, and Clp/F was 21.93 +/- 5.18 L/h; the 24-hour urinary recovery was 69.33 +/- 6.13% and the renal clearance was 12.58 +/- 2.99 L/h. The above pharmacokinetic parameters obtained from the two regimens were compared by two-way ANOVA corrected for the change-over effect. No significant difference was found for Tmax, T1/2 or renal clearance (p > 0.05). Higher AUC, Cmax, urinary recovery and lower Clp/F values were observed for the regimen with food (p < 0.05). The plasma drug concentrations resulting from the regimen with food were higher throughout the 12-hour sampling period when compared to the regimen without food.(ABSTRACT TRUNCATED AT 250 WORDS)     

Saturation and inversion transfer studies of creatine kinase kinetics in rabbit skeletal muscle in vivo

The steady-state kinetics of the creatine kinase reaction in rabbit skeletal muscle in vivo was investigated using inversion and saturation magnetization transfer techniques. Both techniques determined the forward rate of this reaction (creatine phosphate ATP) as approximately 0.3 s-1. This corresponds to a flux of 10 mumol creatine phosphate/s/g muscle. The saturation transfer technique underestimated the reverse reaction by approximately 56%. This result is likely due to the participation of ATP in other interactions in skeletal muscle not involving creatine phosphate.     

Classification of spatiotemporal hemodynamics from brain perfusion MR images using expectation-maximization estimation with finite mixture of multivariate gaussian distributions.

The ability to cluster different perfusion compartments in the brain is critical for analyzing brain perfusion. This study presents a method based on a mixture of multivariate Gaussians (MoMG) and the expectation-maximization (EM) algorithm to dissect various perfusion compartments from dynamic susceptibility contrast (DSC) MR images so that each compartment comprises pixels of similar signal-time curves. This EM-based method provides an objective way to 1) delineate an area to serve as the in-plane arterial input function (AIF) of the feeding artery for adjacent tissues to better quantify the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT); 2) demarcate regions with abnormal perfusion derangement to facilitate diagnosis; and 3) obtain parametric maps with supplementary information, such as temporal scenarios and recirculation of contrast agent. Results from normal subjects show that perfusion cascade manifests (in order of appearance) the arteries, gray matter (GM), white matter (WM), veins and sinuses, and choroid plexus mixed with cerebrospinal fluid (CSF). The averaged rCBV, rCBF, and MTT ratios between GM and WM are in good agreement with those in the literature. Results from a patient with cerebral arteriovenous malformation (CAVM) showed distinct spatiotemporal characteristics between perfusion patterns, which allowed differentiation between pathological and nonpathological areas.     

Creating a professional practice environment on a shoestring

Did you ever think, “If we just had a little money we could…”? The current health care environment is wrought with financial stressors that can be overwhelming and take up most of our time. Such stress can limit the development of a professional practice environment if you let it. How do you not only survive but thrive in this financial climate?     

Magnetic nanoparticle labeling of mesenchymal stem cells without transfection agent: cellular behavior and capability of detection with clinical 1.5 T magnetic resonance at the single cell level.

The purpose of this work was to evaluate the efficacy of labeling human mesenchymal stem cells (hMSCs) by ionic superparamagnetic iron oxide (SPIO) without a transfection agent and verifying its capability to be detected with clinical 1.5 T magnetic resonance (MR) at the single-cell level. Human hMSCs were incubated for 24 h with an ionic SPIO, Ferucarbotran. The labeling efficiency of hMSCs was determined by iron content measurement spectrophotometrically, and the influence of labeling on cell behavior was ascertained by examination of cell viability using the trypan blue exclusion method, cell proliferation analysis using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, mitochondrial membrane potential (MMP) change, differentiation capacity, and reactive oxygen species (ROS) production measured by dichlorofluorescein diacetate (DCFDA) fluorescent probe. Labeled hMSCs were scanned under 1.5 T MRI with three-dimensional (3D) and two-dimensional (2D) T(2)-weighted gradient echo (GRE) pulse sequences. Human hMSC labeling without transfection agent was efficient. The iron content in hMSCs was 23.4 pg Fe/cell. No significant change was found in viability, proliferation, MMP change, ROS production, or differentiation capacity. About 45.2% of the hMSCs could be detected using 1.5 T MRI at the single cell level with 3D GRE and four repetitions.     

Prediction of functional outcomes in stroke inpatients receiving rehabilitation.

BACKGROUND AND PURPOSE: Early identification of predictive factors relevant to functional outcomes for stroke patients is important to the establishment of an effective continuing care program. The objective of this study was to identify the predictive factors related to functional outcome at discharge after stroke rehabilitation therapy. METHODS: 105 first-time stroke patients admitted to the inpatient rehabilitation department of a university-based medical center were recruited for this prospective study. The functional outcomes of the patients were assessed at admission and at discharge using the Functional Independence Measure (FIM). Severity of stroke was determined using the Canadian Neurological Scale (CNS). Age, gender, side of hemiplegia (SIDE), type of stroke (TYPE), onset to admission interval (OAI), and length of rehabilitation stay (LORS) were also included as predictor variables. RESULTS: The mean (+/- SD) FIM score at discharge (76.6 +/- 26.4) correlated strongly (r = 0.78, p < 0.001) with the admission FIM score (56.3 +/- 24.1), moderately (r = 0.46, p < 0.001) with the admission CNS score (6.1 +/- 2.2), negatively (r = -0.38, p < 0.001) with age (63.2 +/- 12.3 years), negatively (r = -0.26, p = 0.009) with OAI (24.2 +/- 16.0 days), and negatively (r = -0.29, p = 0.002) with LORS (34.7 +/- 16.8 days). Stepwise regression analyses indicated that admission FIM score, age, and admission CNS score were the strongest predictors of functional outcome and accounted for 66% of the total variation in discharge FIM total score. The admission FIM score was the best predictor and accounted for 61% of the variation. CONCLUSIONS: The findings of this study imply that the admission FIM scores for inpatients receiving stroke rehabilitation can be used to predict functional outcomes at discharge from hospital.     

Three-dimensional ultrasound diagnosis of Larsen syndrome with further characterization of neurological sequelae.

Larsen syndrome consists of skeletal dysplasia with multiple joint dislocations and a characteristic facies. The basis of this abnormality is a generalized mesenchymal disorder involving connective tissues. We describe our findings in a woman who was referred at 28 weeks' gestation due to multiple fetal anomalies suspected initially at an 18-week ultrasound examination. On three-dimensional (3D) ultrasound we found the fetus had bilateral genu recurvatum. Further 3D examination at 36 weeks confirmed the lower limb anomaly and revealed facial anomalies that led to the diagnosis of Larsen syndrome. An elective Cesarean section was performed at 38 weeks' gestation to minimize neurological sequelae. Magnetic resonance imaging was performed postnatally and showed pachygyria, colpocephaly and agenesis of the corpus callosum. In this case, 3D ultrasound facilitated the prenatal diagnosis of Larsen syndrome. A careful prenatal investigation for other associated anomalies such as those of the cardiovascular or neurological systems is warranted with this diagnosis. These associated lesions are likely to have a greater impact on prognosis than the classic symptoms of Larsen syndrome and a collaborative approach is necessary to optimize delivery and postnatal management of an affected fetus.