[Determination of myristicin and safrol in the volatile oil of semen Myristicae and its processed products by TLC-scanning]

This paper reports the determination of myristicin and safrol in the volatile oil of Semen Myristicae and its processed products by TLC-Scanning. The results showed that in the processed products myristicin decreased markedly and safrol decreased slightly. The quantity of myristicin roasted with paste less than with wheat bran less than with talcum powder less than the unprocessed one. The toxicity of Semen Myristicae is related to the quantities of myristicin.

Sympathoadrenal excitation and inhibition by lower brainstem stimulation in cats

Effects of stimulation of brainstem sites on hemodynamics and plasma catecholamine levels were assessed in cats under chloralose-urethane anesthesia. Pressor areas of the dorsal medulla (DM) and ventrolateral medulla (VLM) and the depressor area of the paramedian reticular nucleus (PRN) were stimulated electrically using a monopolar electrode, or chemically using sodium glutamate microinjection. Plasma levels of norepinephrine (NE) and epinephrine (EPI) were measured in caval blood above the adrenal veins. Electrical stimulation of the DM and VLM produced increases in blood pressure and in plasma NE and EPI levels that were enhanced after acute vagotomies. The NE and EPI responses were attenuated after acute, bilateral adrenalectomies, confirming augmented adrenomedullary secretion, whereas the pressor responses were intact. Injection of sodium glutamate into the same pressor regions of the DM or VLM also produced pressor responses and elevated plasma catecholamine levels, indicating that the responses resulted from activation of neuronal perikarya. Stimulation of the PRN attenuated pressor and catecholamine responses during stimulation of the DM and VLM. The results indicate that pressor responses during stimulation of the DM and VLM are due at least partly to activation of perikarya in these regions, are associated with but not dependent on adrenomedullary activation, and are enhanced after vagotomy; and that neurons of the PRN exert inhibitory modulation of the pressor and adrenomedullary responses during stimulation of VLM and DM.

Effect of region-of-interest in computerized densitometric analysis of radiographs

The region-of-interest (ROI) in computer-assisted densitometric image analysis (CADIA) is defined by its size and location. This study evaluated the effects of these variables on two quantitative parameters, the change in density and the area with change in density. Pairs of radiographs for these analyses were obtained from sites with "no change" or "known loss" in Cynomolgus monkeys during a study of ligature-induced periodontitis. The size and location of the ROI had clear effects on the two CADIA parameters. To reduce these effects, a corrective procedure hypothesizing a linear relationship between the ROI size and the area with change in density was tested. While this procedure was sufficient to correct for ROI size-dependent differences among "no change" images, it was not effective in images with "known loss". In such images, additional adjustments by increasing threshold levels for the registered change in density were found to reduce but not to eliminate differences between ROIs of different size and location. When densitometric radiographic analysis is used for quantitative comparison of different sites, it is primarily recommended to select ROIs of similar size and location. Application of corrective procedures should follow only after careful evaluation of their effects on sensitivity and specificity.

Role of selenium-dependent glutathione peroxidase in protecting against t-butyl hydroperoxide-induced damage in hepatocytes

The role of the selenoenzyme glutathione peroxidase (Se-GSHPx) in protecting against oxidative injury was studied in hepatocytes isolated from rats fed either a low-selenium (Se-) or a selenium-adequate (Se+, control) diet. In rats fed Se- diet for eight weeks the selenium content of plasma and liver was lowered to 15 and 8%, respectively. No Se-GSHPx and only 5% of total GSHPx activity was detected in Se- hepatocytes. However, the Se- hepatocytes were as resistant as the Se+ cells to oxidative injury by 0.8 mM tert-butyl hydroperoxide (t-BuOOH), or 0.2 mM t-BuOOH plus 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), an inhibitor of oxidized glutathione (GSSG) reductase. Only at 1.5 mM t-BuOOH or at 0.5 mM t-BuOOH with BCNU were cell damage and lipid peroxidation more evident in Se- cells. At all t-BuOOH concentrations used the depletion of cellular glutathione (GSH) was similar in magnitude in Se- and Se+ cells, but Se+ cells released more glutathione (mainly GSSG), obviously due to their higher Se-GSHPx activity. These results suggest that hepatocytes devoid of Se-GSHPx activity maintain a high capacity to resist peroxidative attack, either via residual (non-Se)GSHPx activity or other compensatory GSH-associated detoxication mechanisms.

MR angiography by multiple thin slab 3D acquisition

Multiple overlapping thin 3D slab acquisition is presented as a magnitude contrast (time of flight) technique which combines advantages from multiple thin slice 2D and direct 3D volume acquisitions to obtain high-resolution cross-sectional images of vessel detail. Details of implementation and example images are presented.

Normal venous anatomy of the brain: demonstration with gadopentetate dimeglumine in enhanced 3-D MR angiography

This investigation evaluates whether gadopentetate dimeglumine enhancement of three-dimensional (3-D) acquisition MR angiography can generate clinically useful images of the normal venous anatomy of the brain. 3-D MR angiography of normal cerebral arterial anatomy has made rapid progress, although demonstration of detailed venous anatomy with similar techniques has been much less revealing. To overcome the limitation of slow venous flow, IV gadopentetate dimeglumine contrast enhancement was used to alter the relaxation times of blood, thus augmenting the venous signal. Several groups of patients were evaluated: we studied eight patients both with and without contrast enhancement, 20 patients and volunteers with multiple techniques to determine optimal technical parameters, and seven patients in whom enhanced MR studies were compared with standard selective biplane cut-film arterial angiograms. Only the large dural sinuses (such as the transverse sinus) could be seen on unenhanced studies owing to the saturation of slowly flowing venous spins. With contrast enhancement, many of the important small and large cerebral venous structures were routinely seen with reasonable scanning times (7 min). The venous anatomy was well seen for approximately one-half hour after injection and correlated well with angiograms. There are several important limitations to this technique, including a limited field of view, variable visibility of specific veins owing to technical and physiologic factors, confusion of enhancing non-flow-related structures, and lack of detailed physiologic information. Single excitation 3-D MR angiograms are insensitive in the evaluation of cerebral venous structures. Enhancement with gadopentetate dimeglumine affords rapid scanning and excellent visualization of the pertinent venous anatomy. The best image quality was obtained with a sequence of 50/7/30 degrees (TR/TE/flip angle).

[A pharmacognostical study on the fruits of Cnidium monnieri (L.) Cuss]

The fruits of three species are used as the Chinese drug "Shechuangzi", namely Cnidium monnieri, C. monnieri var. formosana and C. japonicum, among which only C. monnieri is the real sort. The authors have distinguished them by macroscopic and microscopic structures and TLC. The total coumarin, trace element and amino acid contents are reported.

Volume MR angiography: methods to achieve very short echo times

Angiographic displays of cerebral vessels can be generated with single-excitation three-dimensional magnetic resonance imaging. Differentiation of true stenosis from artifactual signal loss, due to dephasing effects from fast or nonconstant blood flow and field inhomogeneities, poses a significant clinical problem that can be largely resolved with the use of very short echo times (TEs). A three-dimensional imaging technique was developed that allows TEs of 3.1 msec without and 4.5 msec with first-order flow compensation gradients. The short TEs were achieved with short asymmetric radio-frequency pulses, gradients of minimal duration, and fractional echoes. Significantly improved images of normal tortuous vessels with fast flow were obtained. With this method, accuracy in depicting the vessel lumen and confidence in the findings were markedly increased.

[Immune response and post inoculation reactions of simultaneous administration of hepatitis B vaccine with routine vaccine in children, III. Immune response and post inoculation reactions of simultaneous administration of hepatitis B vaccine and BCG, meningococcus group A polysaccharide vaccine]

The results of the immune response and post inoculation reactions of simultaneous administration of BCG, meningococcus group A polysaccharide vaccine and hepatitis B vaccine were reported. 360 newborn babies (1-3 days of age) were divided into five groups. The babies in group No. 1 were vaccinated with hepatitis B vaccine alone, babies in group No. 2 were vaccinated with BCG for scarification within 3 days after delivery and meningococcus group A polysaccharide vaccine in 6 months of age; babies in group No. 3 were vaccinated with hepatitis B vaccine, BCG for scarification and Meningococcus group A polysaccharide vaccine simultaneously, babies in group No. 4 were vaccinated with intradermal BCG and Meningococcus group A polysaccharide vaccine separately, babies in group No. 5 were vaccinated with hepatitis B vaccine, intradermal BCG and meningococcus group A polysaccharide vaccine simultaneously. The results of the immune response of the combination of hepatitis B vaccine with BCG, meningococcus group A polysaccharide vaccine were similarly to the immune response observed after immunization of each vaccine alone in children. The general post inoculation reactions of all vaccines were mild. There was no significant difference among all 5 groups. The data showed that children could be immunized with hepatitis B vaccine, BCG and meningococcus group A polysaccharide vaccine simultaneously.

Correction of density changes caused by methodological errors in CADIA

Quantitative evaluation of radiographic changes by computer-assisted densitometric image analysis (CADIA) requires exact knowledge about method errors. In the present study, density change errors were determined from pairs of films with "no change". From this distribution of error values, a series of threshold values for correction of changes due to method errors was selected. The threshold values were then applied to results from analysis of densitometric changes in sites with "known loss" or "no change" of the alveolar bone among films from cynomolgus monkeys. The density errors formed non-normal distributions with no difference in magnitudes between the absolute values expressing density decreases and density increases in the same areas. Calculation of sensitivity, specificity, type 1 and type 2 errors showed that these variables were clearly influenced by selection of different threshold values for correction of the density change errors. It is therefore recommended that threshold values be determined for each analytical system initially as well as following any equipment or computer program modification. Before selecting the threshold value for a specific radiographic analysis, the desired level of sensitivity and specificity should be evaluated.

Recognition and management of Budd-Chiari syndrome: report of one hundred cases

Budd-Chiari syndrome is an unusual form of portal hypertension caused by occlusion of the hepatic venous outflow, and it is often confused with portal hypertension caused by liver cirrhosis. Its prognosis is poor, and optimal therapy remains to be established. This is a report of 100 confirmed cases of this syndrome treated from December 1982 to March 1988 at two vascular centers in China. Sixty-two male and 38 female patients, 15 to 62 years of age (mean age, 32.6 years) were treated. Seventy-six patients had intractable ascites, 56 had esophageal varices, and 22 had upper gastrointestinal bleeding. There were 37 cases of membranous obstruction, 57 cases of occlusion of the inferior vena cava above the confluence of the hepatic veins, and 6 cases of occlusion of the hepatic veins. Eighty-one patients were operated on. Operative mortality rate was 8.6% (7/81). Follow-up from 2 to 66 months revealed that 58 of the patients operated on (72%) had good results, whereas 11 of 19 (58%) patients treated nonoperatively died within 2 months after admission. On the basis of these data we conclude that the operative procedure must be tailored to the cause and underlying pathologic characteristics. Mesoatrial shunting is the operation of choice for patients with occlusion of the retrohepatic inferior vena cava and hepatic veins, and inferior vena cava--atrial shunting is the operation of choice for patients with occlusion of the inferior vena cava and patency of the hepatic veins. Membranotomy is used for patients with inferior vena cava webbing, and mesocaval shunting is used for patients with intrahepatic venous occlusion only.(ABSTRACT TRUNCATED AT 250 WORDS)

Seroepidemiologic study of rubella in selected Chinese female

To have a better understanding of rubella seroepidemiology among female population in Taiwan, we report a serologic survey of 4030 examinations for 2030 school girls and 2000 pregnant women, using enzyme-linked immunosorbent assay for the detection of rubella specific IgG. RA 27/3 vaccines were given to susceptible volunteer students and postpartum women for the evaluation of vaccine efficiency and its side effects. The results showed that the rubella susceptible female among 8 to 22-year-old girl students was 44.97%, which was higher than expected, as most of them experienced the outbreak of rubella in 1977. The susceptibility rate among the pregnant women was 19.35%, which was also higher than expected for an age group having been through two outbreaks in the past. All the vaccinees showed good tolerance to the vaccine and the seroconversion rate was 100%. With such high susceptibility rate among women of child bearing age and girl students, plus the endemic property of rubella infection in Taiwan, we can expect a high risk of congenital rubella syndrome. Mass vaccination against rubella should be brought into effect immediately.

Flow-induced phase effects and compensation technique for slice-selective pulses

Flowing spins experience a time-varying frequency during the application of slice-selective radiofrequency (RF) pulses. As a result the flowing spins accumulate phase relative to stationary spins as the spins are rotated toward the transverse plane. Using finite difference techniques to solve the Bloch equations for flowing spins, the phase of the transverse magnetization after a slice-selective pulse was evaluated for varying flow velocities and for tip angles which ranged between 0 degrees and 180 degrees. The following results were obtained for constant slice thickness: (1) For a fixed tip angle, the phase varies nonlinearly with velocity. (2) For a fixed velocity, the phase varies nonlinearly with tip angle. For small tip angles the nonlinearity in the variation as a function of velocity is very small but increases for tip angles greater than 90 degrees and becomes especially severe near 180 degrees. A method is proposed to desensitize the phase of flowing spins during the application of slice-selective pulses. The compensation scheme depends upon tip angle but is virtually independent of flow velocity. The technique was tested and verified with clinical images.

The solution of Bloch equations for flowing spins during a selective pulse using a finite difference method

The movement of spins during periods of selective pulses result in a modulation of the signal intensity and phase of the received magnetic resonance imaging (MRI) signal, and is a major cause of signal loss from vessels imaged with slice-selective pulses. Methods are well developed for compensation of phase perturbations for spins flowing at constant velocity during the time of applied gradients. However, for spins flowing during selective pulses, the magnitude of the amplitude and phase perturbations has not been understood nor to this time has any method of flow compensation been proposed. This is due in part to the difficulty in using the Bloch equations to quantify the amplitude and phase modulation during radiofrequency (rf) excitation since solutions cannot be obtained analytically. In this paper a finite difference method is used to solve Bloch equations for flowing spins during a 90 degrees selective pulse. Compared with stationary spins, the magnetization distribution for flowing spins exhibits a shift of the slice profile in the direction of the flow, an expansion of the profile, phase shifts, and changes in profile shape. The profiles show residual phase errors which become more severe with higher flow velocities, with flow compensation schemes which apply in the case of spins flowing during applied gradients, and in the absence of an rf pulse. The measurement and understanding of the magnetization distribution is important to designing pulse sequences that compensate for flow. Flow compensated pulse sequences are necessary to reduce image flow artifacts and to increase signal of vessels in MR angiographic images.