In vivo stability and disposition of a self-stabilized oligodeoxynucleotide phosphorothioate in rats

The use of antisense oligonucleotides represents a novel, genetically based therapy. The biostability and pharmacokinetics of a 33-mer self-stabilized oligodeoxynucleotide with significant anti-HIV activity was determined in rats after intravenous administration of [35S]oligodeoxynucleotide. Plasma disappearance of the labeled oligodeoxynucleotide could be described by a two-compartment model, with half-lives of 0.54 and 41.44 h. The oligodeoxynucleotide in plasma remained mainly intact. Urinary excretion represented the major elimination pathway, with approximately 27% of the administered dose excreted within 24 h and 57% over 240 h. The majority of radioactivity in urine was attached to degradative products. Fecal excretion was a minor elimination pathway. A wide tissue distribution of the oligonucleotide was observed, with the majority of radioactivity in most tissues being intact. Compared with other linear oligonucleotide phosphorothioates, the self-stabilized oligonucleotide was more stable in vivo, which may be important in development of antisense oligonucleotides as therapeutic agents.

Pharmacokinetics and tissue distribution in rats of an oligodeoxynucleotide phosphorothioate (GEM 91) developed as a therapeutic agent for human immunodeficiency virus type-1

An antisense oligodeoxynucleotide phosphorothioate, namely gene expression modulator 91 (GEM 91), has been demonstrated to have significant anti-human immunodeficiency virus activity in various tissue culture models. The present study was undertaken to determine the pharmacokinetics and tissue distribution of GEM 91 in rats following i.v. bolus administration of 35S-radiolabeled GEM 91. Plasma disappearance curves for GEM 91-derived radioactivity could be described by the sum of two exponentials, with half-lives (mean +/- SEM) of 0.95 (+/- 0.07) and 47.57 (+/- 14.48) hr. Urinary excretion represented the major pathway of elimination of GEM 91, with 26.67 +/- 6.46% (mean +/- SD) of the administered dose excreted within 24 hr and 58.12 +/- 4.36% over 240 hr after GEM 91 administration. Fecal excretion was a minor pathway of elimination of GEM 91 with 1.4 +/- 0.62% (mean +/- SD) of the administered dose excreted over 24 hr and 8.54 +/- 0.64% over 240 hr. A wide tissue distribution of GEM 91 was observed. During the initial 30 min, the highest levels of tissue radioactivity were found in the kidney, liver, spleen, lungs, and heart. Radioactivity was retained over longer time periods in the kidneys, liver, heart, and intestine. Analyses of the extracted radioactivities from plasma, kidney, and liver by gel electrophoresis showed the presence of both intact GEM 91 and degradative products with smaller molecular weights. Radioactivity in urine was found to be degradative metabolites of GEM 91. Based on the experimental data, pharmacokinetic parameters for GEM 91 in each tissue and biological fluids were calculated using computer-based two-compartmental i.v. bolus or absorption models. This study is important not only in providing the basis for future studies of GEM 91 in humans, but also in understanding the pharmacology and toxicology of antisense oligodeoxynucleotide phosphorothioates, in general.

Image-guided insertion of transpedicular screws. A laboratory set-up

STUDY DESIGN

A computer-assisted system allowing precise preoperative planning and real-time intraoperative image localization of surgical instruments is tested in a laboratory setup.

OBJECTIVES

The purpose of this study is to assess the applicability, functionality, and accuracy of this transpedicular spinal fixation technique.

SUMMARY OF BACKGROUND DATA

Most techniques in transpedicular spinal fixation rely on the identification of predefined targets with the help of anatomic landmarks and on the intraoperative use of image intensifiers. Various studies report considerable screw misplacement rates which may lead to serious clinical sequelae such as permanent nerve damage.

METHODS

The proposed system was tested in an in vitro setup drilling 20 pedicle pilot holes in lumbar vertebrae. The accuracy was assessed using precision cuts through the pedicles and simulation of a 6-mm pedicle screw insertion.

RESULTS

An ideal screw position was found in 70 of 77 cuts, and in no case was an injury to the pedicular cortex observed.

CONCLUSIONS

The presented technique provides a safe, accurate, and flexible basis for transpedicular screw placement in the spine. This approach should be further evaluated in clinical applications.

Sodium pentobarbital versus alpha-chloralose anesthesia. Experimental production of substantially different slopes in the transmural CP/ATP ratios within the left ventricle of the canine myocardium

BACKGROUND

Transmural analyses of the creatine phosphate (CP)/ATP ratio in various lamina of the canine myocardium have previously revealed significant variations in the CP/ATP ratio, with the subendocardial layer displaying a decreased ratio relative to the subepicardial layer. Without exception, these results were obtained under sodium pentobarbital anesthesia. These findings have been interpreted to imply that the normal endocardium may be operating in the oxygen-limited domain or that there are transmurally varying set points for the regulation of oxidative phosphorylation.

METHODS AND RESULTS

In this work, we examine the effect of the anesthetic regimen on the transmural CP/ATP ratio within the left ventricular wall of the canine myocardium using spatially localized 31P-nuclear magnetic resonance (NMR) and an open-chest model. Two anesthetics were compared, alpha-chloralose and sodium pentobarbital. Under sodium pentobarbital, the CP/ATP ratio ranged from 1.92 +/- 0.06 to 2.51 +/- 0.08 from endocardium to epicardium, resulting in a transmural slope in the CP/ATP ratio of 0.149 +/- 0.047 (n = 22). Under alpha-chloralose, CP/ATP ratios ranged from 2.18 +/- 0.05 to 2.32 +/- 0.06, with a transmural slope of 0.035 +/- 0.018 (n = 38). Thus, the transmural slope in CP/ATP ratio was nearly four times greater with sodium pentobarbital than with alpha-chloralose, and the difference in these slopes was statistically significant (P = .029). No difference was observed in average CP/ATP obtained from the entire wall with either anesthetic.

CONCLUSIONS

These results demonstrate that the transmural trend in CP/ATP ratio previously reported in the myocardium is likely to be a direct reflection of the sodium pentobarbital anesthetic regimen, not truly reflecting the trend in the normal unanesthetized animal. Moreover, since the transmural variation in CP/ATP ratio was greatly reduced with alpha-chloralose, it appears unlikely that the endocardium in the normal unanesthetized heart is operating in the oxygen-limited domain. These results also point to the importance of the anesthetic regimen in biochemical analysis, indicate the necessity of increased caution in directly translating results obtained under anesthesia, and demonstrate the unique power of in vivo NMR to extract such subtle biochemical information.

[Nationwide survey of the distribution of human parasites in China--infection with parasite species in human population]

The infection rate of main species of parasites and their character by first nationwide survey of human parasites was made. The overall infection rate of human intestinal parasite and the infection rate of most species of parasites were higher in females than that in males. The infection rate according to the age group, the highest infection rate was found in the group aged 5-14 years. With regard to the relation between parasitic infections and occupations of the infected persons, the highest infection rates of Ascaris lumbricoides were exhibited in school children, of hookworm and Clonorchis sinensis were in halfpeasants and halfmerchant and vegetable grower; of Trichuris trichiura were in fishers, of Giardia lamblia, Entamoeba histolytica and Taenia were in herdsmen and halfherdsmen and halfpeasants. In this survey it is also shown that each nationality has their main species of parasites. The family clustering of some main parasites were proved by some province/autonomous region/municipality.

31P-nuclear magnetic resonance studies of chronic myocardial ischemia in the Yucatan micropig

In this work, an x-irradiation/high fat/high cholesterol diet-induced atherogenic model was invoked to examine the effects of severe diffuse atherosclerosis on myocardial metabolism in the in vivo porcine heart. This model was studied using spatially localized 31P-nuclear magnetic resonance (NMR) to monitor pH and the levels of inorganic phosphate, phosphomonoesters, creatine phosphate, and adenosine triphosphate as a function of workload transmurally in control swine and in animals suffering from chronic ischemic heart disease. These preliminary studies revealed that the development of severe atherosclerosis and the accompanying chronically diseased state produce changes in high energy phosphates and that increases in rate pressure products result in demonstrable signs of ischemia in the myocardium which span the entire left ventricular wall. Ischemic changes include a global increase in inorganic phosphate and corresponding decreases in creatine phosphate, ATP, and pH. Importantly, changes in intracellular pH are noted with even the slightest increase in workload suggesting that these diseased hearts display elevated glycolytic activity. By challenging these animals with increased cardiac workload, we directly visualize how the chronically compromised heart responds to severe oxygen challenges in a clinically relevant model of this situation.

[Characteristics and recent trends in endemicity of human parasitic diseases in China]

An analysis of the nationwide survey of the distribution of human parasites in the light of the literature previously published, two major trends in the endemicity of parasitic diseases in China was observed. For one trend, the infection rate of E. histolytica, Fasciolopsis buski and soil-transmitted helminthasis etc. declined markedly. The second trend was that the prevalence of food-transmitted parasitic diseases (Trichinella spiralis, Clonorchis sinensis, Paragonimiasis, cysticercosis) and hydatidosis was increasing. The relationship between the social economic factors and the two trends were discussed.

Evaluating a computer-based experiential learning simulation: a case study using criterion-referenced testing

A case study of a computer-based experiential learning program involving the use of criterion-referenced testing as a quantitative evaluation tool is described. The simulation was designed to introduce nurses to basic computer operations. One hundred and thirty-eight nurses participated in the evaluation using a specially prepared version of the program that recorded the time required to perform actions, the number of unsuccessful attempts to complete instructions, and the number of correct responses to specific questions. The ability of the nurses to "drag and drop" increased significantly from less than 20% to more than 90% (p < .05, Student's t-test). Their knowledge of the definitions of four computer-related terms (i.e., trackball, desktop, window, and icon) increased significantly (from 65% to 80%, p < .1). In subjective evaluations, 82% of respondents reported that they enjoyed the lesson and 89% wanted more computer-based instructional units to be developed. Use of criterion-referenced testing helped to shed new light on the utility of such computer aided instructional systems.

Uptake, intracellular distribution, and stability of oligodeoxynucleotide phosphorothioate by Schistosoma mansoni

The in vitro uptake, cellular distribution, efflux, stability, and toxicity levels of an oligodeoxynucleotide phosphorothioate (PS-oligonucleotide) have been studied in mature Schistosoma mansoni worms. The intracellular accumulation of 35S-labeled PS-oligonucleotide occurred roughly in proportion to the worm body mass over a wide concentration range, whether the worms were exposed singly or in mating pairs. Cellular uptake was dependent on the extracellular concentration. A minor fraction (13%) of the PS-oligonucleotide taken up by the worm accumulated in the surface tegumental coat. Most of the PS-oligonucleotide taken up localized in the cytosol (54%) and the nuclei-enriched (33%) fractions. In a time course study on adult worms in culture, oligonucleotide uptake was observed within the first 2 h and peaked at about 36 h. A decrease in the intracellular concentration of the PS-oligonucleotide was observed by 42 h. Analysis of the extracted oligonucleotides showed that PS-oligonucleotide was digested slowly. Efflux of the oligonucleotide was time and temperature dependent. Significant toxicity to the cultured worms did not occur until the PS-oligonucleotide concentration was over 8 mg/ml (1 mM).

[Clinical trial of high-dose medroxyprogesterone acetate in advanced breast cancer]

Sixty-two evaluable patients with advanced breast cancer were treated with medroxyprogesterone acetate (Farlutal. Erba) 500mg orally twice or three times a day. After thirty days, one patient had a complete response (1.6%), 33 patients had partial response (53.2%). 11 had stable disease (17.7%), and 17 progressive disease (27.4%). The response rates of bone, lung and chest wall metastasis were higher. And the older patients showed a better response than the younger. The response did not show significant correlation with KPS, menopausal status, disease-free intervals after operation, numbers of metastases and the dose of medroxyprogesterone acetate. The response rate in ER positive patients was higher than the ER negative, but the difference was not statistically different. The side effects of high-dose medroxyprogesterone acetate were well tolerated and the most common ones were weight gain and excessive perspiration.

[The effect of nutrition support and recombinant growth hormone on body composition and muscle function in postoperative patients]

To determine the effects of nutritional support and recombinant human growth hormone (GH) on body composition and muscle function, we performed a randomized double-blind trial in 18 patients after elective gastrectomy or colectomy. Same amount of calories and amino acids were administered. Daily injection of GH or placebo was given during the first postoperative week. The GH dose was 0.2 IU/kg/d. The study of body composition demonstrated that control subjects lost lean body mass and fat 2.8 +/- 1.46kg and 0.49 +/- 1.3kg, respectively. In contrast, study group subjects lost the fat 0.95 +/- 0.46kg. Hand grip strength fell with time in the control group (P < 0.05). In contrast, grip strength of GH-treated subjects was significantly different from controls (P < 0.01). The study results demonstrated that nutritional support and growth hormone can maintain lean body mass and muscle function in postoperative patients.

The dynamic change of plasma endothelin-1 during the perioperative period in patients with rheumatic valvular disease and secondary pulmonary hypertension

The arterial plasma endothelin-1 concentration was substantially more elevated in 15 patients with rheumatic valvular disease and secondary pulmonary hypertension than in healthy volunteers (3.66 +/- 2.20 versus 1.17 +/- 0.38 pg/ml, mean +/- standard deviation; p < 0.01). The preoperative plasma endothelin-1 level was highly correlated with the pulmonary hemodynamics: pulmonary artery systolic pressure (r = 0.94, p < 0.001), pulmonary artery mean pressure (r = 0.86, p < 0.001), pulmonary capillary wedge pressure (r = 0.82, p < 0.001), and pulmonary vascular resistance (r = 0.63, p < 0.02). After valve replacement, the plasma endothelin-1 concentration declined substantially and the pulmonary hemodynamics improved markedly. Two weeks after the operation, the plasma endothelin-1 level in patients (1.26 +/- 0.45 pg/ml, mean +/- standard deviation) was not statistically different from that in the healthy volunteers. The plasma endothelin-1 concentration continuously increased during the course of cardiopulmonary bypass and peaked after cessation of bypass. The peak plasma endothelin-1 level (13.49 +/- 4.60 pg/ml, mean +/- standard deviation) positively correlated with the bypass time (r = 0.64, p < 0.02) and negatively correlated with the urine volume during bypass (r = -0.69, p < 0.01). We conclude that (1) increased plasma endothelin-1 might be implicated in the pathogenesis of secondary pulmonary hypertension caused by rheumatic valvular disease and (2) markedly elevated plasma endothelin-1 concentrations might be associated with the mechanism of cardiac or renal dysfunction after prolonged cardiopulmonary bypass.

Computer-assisted neurosurgery system: Wayne State University hardware and software configuration

Computer-assisted neurosurgery uses the latest technological advancements in imaging, computers, mechanics, and electronics to improve the accuracy and reduce the invasiveness and risk of neurosurgical procedures. We describe the Wayne State University, Detroit, Michigan, computer-assisted neurosurgical system with the emphasis on software and discuss the theory guiding the development of this system and its application in real-time position tracking systems. Our system consists of the Neurological Surgery Planning System (NSPS) software which we developed at our medical center and three types of position tracking systems: the Zamorano-Dujovny (Z-D) are digitizer for frame-based procedures, an articulated arm, and an infrared-based digitizer for frameless procedures. The NSPS software is designed to offer neurosurgeons a safe and accurate method to approach intracranial lesions by preoperatively planning a surgical trajectory. Software consisting of the most advanced technologies in computer vision, computer imaging/graphics, and stereotactic numeric analysis forms the core of the system. Capabilities for correlating data from imaging studies to facilitate image reconstruction, image mapping, and three-dimensional (3D) visualization of target volumes enable the neurosurgeon to simulate surgical procedures into a preoperative protocol to be used during surgery, both to follow the preplanned trajectory and to track the position of surgical instruments in real-time on the computer monitor. The tracking systems position and orient the surgical instruments relative to the patient's head. With these devices, the display of the surgical instruments together with the virtual images create an excellent intraoperative tool.

Clinical significance of coronary flow reserve: effect of papaverine and exercise

BACKGROUND

The clinical significance of coronary flow reserve (CFR) was evaluated after pharmacological (papaverine) and physiological (exercise) vasodilation in patients with coronary artery disease (CAD).

METHODS

CFR was determined using parametric imaging in 10 patients with normal coronary arteries (group 1) and in 10 with CAD (group 2). Contrast density and mean appearance time were measured (region of interest = 249 pixels) in the perfusion beds of the left circumflex and the left anterior descending coronary arteries at rest, 45 s after 10 mg intracoronary papaverine, and during supine bicycle exercise. CFR was calculated from coronary perfusion after papaverine divided by perfusion at rest and coronary perfusion during exercise divided by perfusion at rest. Perfusion zones in patients with CAD were subdivided into regions supplied by a non-stenosed (group 2a) and a stenosed (group 2b) coronary artery.

RESULTS

In control patients, heart rate increased from 75 beats/min at rest to 125 beats/min during exercise, and in patients with CAD from 63 to 107 beats/min, respectively. Mean aortic pressure showed a significant increase during exercise in both groups. Mean pulmonary artery pressure increased significantly during exercise from 19 to 28 mmHg in control patients and from 22 to 42 mmHg in the CAD group (P < 0.001). Coronary driving pressure (mean aortic minus diastolic pulmonary artery pressure) tended to increase during exercise in the control group (from 90 to 101 mmHg, NS) and remained nearly unchanged in patients with CAD (from 92 to 94 mmHg, NS). In the control group, CFR was significantly higher during exercise than after papaverine (4.0 versus 3.5, respectively; P < 0.01). However, coronary resistance (coronary driving pressure divided by coronary flow index) was similar after papaverine and during exercise. In patients with CAD, papaverine-dependent CFR was significantly reduced in the perfusion zone of the stenosed (2.1) but not of the non-stenosed coronary artery (3.0). In contrast, CFR during exercise was significantly decreased in both perfusion zones (2.5 in non-stenosed arteries and 1.5 in stenosed vessels).

CONCLUSIONS

In control patients, CFR is slightly but significantly larger during exercise than after papaverine because of the exercise-induced increase in coronary driving pressure. In contrast, CFR is smaller during exercise than after papaverine in patients with CAD, most probably as a result of secondary mechanisms such as exercise-induced narrowing of stenosed vessels or an increase in extravascular resistance. Thus, CFR based on papaverine appears to be of limited value for assessing the functional significance of a stenotic lesion.

Clinical observation on osteoporosis treated with traditional kidney-tonifying medicaments

The method of scoring kidney deficiency symptoms and bone density was used to judge therapeutic efficacy on osteoporosis of traditional kidney-tonifying drugs. It was proved that the drugs not only improved clinical symptoms but also delayed the developmental process of this disorder. It also verified the correctness of the traditional theory that the kidney dominates the bone and generates the marrow.

Seasonal energy requirements of wapiti (Cervus elaphus) for maintenance and growth

Seasonal energy intakes of 6- to 14-mo-old wapiti hinds were determined in energy balance trials under pen and field conditions in winter, spring and summer. Six animals grazed native pastures supplemented with alfalfa hay when pasture availability declined in winter. Another six were penned and fed alfalfa-barley pellets to maximize growth throughout the year. Season and diet-specific metabolizable energy requirements for maintenance and liveweight gain were determined from regression of metabolizable energy intake on gain. Daily maintenance requirements of penned wapiti ranged from (mean ± SE) 473 ± 35 kJ kg−0.75 in winter to 728 ± 78 kJ kg−0.75 in summer. On spring and summer pasture, daily ecological maintenance requirements ranged from 900 ± 26 to 984 ± 37 kJ kg−0.75. Energy requirements for gain were the same in pen and field trials, ranging from 25 ± 6 to 33 ± 5 kJ g−1 in winter and from 40 ± 6 to 43 ± 12 kJ g−1 in spring and summer. This study provides basic information on the metabolizable energy needs of wapiti and insights into how their seasonal requirements can be optimally met. Key words: Elk, metabolizable energy requirement, growth, physiological maintenance, ecological maintenance, seasonality, energy balance

[Simultaneous determination of serum copper and zinc levels in patients with cancer of the digestive tract by ion-exchange chromatography]

Serum copper and zinc were simultaneously determined by ion-exchange chromatography (IC) in 35 normal volunteers and 45 patients with benign diseases or different stage cancers of the digestive tract. No significant differences of serum Cu, Zn and Cu/Zn ratio were found among normal volunteers, patients with benign diseases and those with stage I or II cancers, while in the group of stage III and IV cancer patients, serum Cu (26.53 +/- 1.41 mumol/L) and Cu/Zn ratio (2.25 +/- 0.16) were very significantly elevated (P < 0.01) and that of serum Zn (11.78 +/- 0.46 mumol/L) was remarkably decreased (P < 0.05). Our results showed that serum Cu, Zn and Cu/Zn ratio were of no help in detecting early stage cancers and in differentiating them from benign diseases but were useful in predicting stages of cancers before operation for a better choice of therapy.

The clinical correlates of high-titer IgG anti-GM1 antibodies

Serum IgG anti-GM1 antibodies have been reported to occur in a variety of disorders, including Guillain-Barré syndrome and chronic polyneuropathies. Of over 5,000 serums tested in our laboratory, high titers of selective IgG anti-GM1 antibodies (> 1:1,000) and without binding to sulfatide were found in 35 patients. Clinical correlation revealed that almost all patients had axonal, motor neuropathies. One subgroup was comprised of individuals with an acute motor neuropathy, described either as an acute axonal Guillain-Barré-like syndrome that was occasionally associated with a prodrome of Campylobacter jejuni enteritis or as Chinese paralysis syndrome. A second group of patients had chronic asymmetric lower motor neuron (LMN) syndromes with no conduction block or other evidence of demyelination. The presence of selective high-titer IgG anti-GM1 antibody reactivity in serum is uncommon but when present is strongly associated with acute axonal motor neuropathies or chronic asymmetric LMN syndromes.

Interactive intraoperative localization using an infrared-based system

Conventional stereotactic surgery has evolved from a ring-based system with a simple software which calculated few parameters to frameless intraoperative localization systems that provide the surgeon with real-time localization and correlation with several imaging modalities. The localization system described in this paper is an opto-electronic system that uses infrared emitters and three precalibrated CCD cameras. The system was chosen among others for the following reasons: it tracks target points defined by up to 256 miniature light emitting diodes, and its accuracy in locating the spatial position of a diode marker in the operating volume 1.0 x 1.0 m at a distance of 2.0 m is 0.1 mm with a resolution better than 0.01 mm. Systems like this one can track and define the position and orientation of any object in the field view of the camera. This is done by attaching a few small infrared emitters (light emitting diodes) to the surface of each 'rigid body' (surgical instrument) being tracked. Subsequently, through a calibration process a corresponding rigid body file is created. This rigid body file represents this particular object (i.e. surgical tool, microscope) and defines a local coordinate system that identifies each translation and orientation of that tool with respect to the camera coordinate system. This in turn is transferred into the computed tomographic/magnetic resonance imaging coordinate system by a process referred to as coordinate matching. Fiducial markers are placed on the patient's head prior to image scanning.(ABSTRACT TRUNCATED AT 250 WORDS)

Zamorano-Dujovny multipurpose neurosurgical image-guided localizing unit: experience in 866 consecutive cases of 'open stereotaxis'

We describe the Zamorano-Dujovny localizing unit which consists of a ring-shaped headholder held on the patient's head by three or four variably placed fixation pins, thereby avoiding interference with the flap sites or craniotomy. The base ring is mounted intraoperatively on a special adapter that allows any patient positioning including supine, lateral prone, 3/4 prone, sitting, etc. Imaging studies, such as computed tomography, magnetic resonance imaging, x-ray, digital angiography, and digital subtraction angiography can be performed with the headholder anchored in place for multimodality image localization. Surgical draping can be done over the ring to provide a completely sterile field. An arc/quadrant localizing device can be mounted on any four alternative positions according to the neurosurgeon's preference. PC-compatible software gives the setting for any possible mounting. Intraoperatively the localizing unit can be used in a 'fixed' permanent setting or as a 'nonfixed' system to provide intraoperative three-dimensional orientation. Different types of instruments compatible with the unit extend its capabilities, such as 'bayonet'-type brain retractors (cylinders and speculum) that keeps the surgical corridor unobstructed from the arc. As an alternative, in the nonfixed setting, self-retaining arms are fixed to the base ring and brain retractors and conventional microsurgical techniques can be used without any mechanical obstruction.

Cytolysin gene expression in the islets of diabetic BioBreeding/Worcester rats

Diabetes prone (DP) BB/Wor rats develop spontaneous autoimmune diabetes mellitus caused by a T cell-dependent process that destroys pancreatic beta cells. Neither the inciting immune system defect nor the mechanism by which beta cells are destroyed is known with certainty. DP rats are severely deficient in certain T cell subsets including CD8+ cytotoxic T cells (Tc) and RT6+ T cells. Diabetes-resistant (DR) BB/Wor rats can be rendered diabetic if depleted of RT6+ T cells. To investigate the mechanisms of beta cell destruction in BB rat diabetes, we determined: 1) the relative abundance of Tc and NK cells in the islets of acutely diabetic DP and RT6-depleted DR rats and 2) expression of mRNA encoding cytolysin, a cytolytic pore-forming protein produced by both Tc and NK cells. We found that in the islets of acutely diabetic DP rats NK cells were about three times more abundant than in diabetic RT6-depleted DR rats. Conversely, in the islets of diabetic DR rats, Tc were three times more abundant than NK cells. In addition, cytolysin gene expression was detected in about 60% of the islets of both DP and DR rats. These data suggest that cytolysin may be a mechanism by which Tc and NK cells damage B cells in vivo.

Cytolysin gene expression in the islets of diabetic BioBreeding/Worcester rats

Diabetes prone (DP) BB/Wor rats develop spontaneous autoimmune diabetes mellitus caused by a T cell-dependent process that destroys pancreatic beta cells. Neither the inciting immune system defect nor the mechanism by which beta cells are destroyed is known with certainty. DP rats are severely deficient in certain T cell subsets including CD8+ cytotoxic T cells (Tc) and RT6+ T cells. Diabetes-resistant (DR) BB/Wor rats can be rendered diabetic if depleted of RT6+ T cells. To investigate the mechanisms of beta cell destruction in BB rat diabetes, we determined: 1) the relative abundance of Tc and NK cells in the islets of acutely diabetic DP and RT6-depleted DR rats and 2) expression of mRNA encoding cytolysin, a cytolytic pore-forming protein produced by both Tc and NK cells. We found that in the islets of acutely diabetic DP rats NK cells were about three times more abundant than in diabetic RT6-depleted DR rats. Conversely, in the islets of diabetic DR rats, Tc were three times more abundant than NK cells. In addition, cytolysin gene expression was detected in about 60% of the islets of both DP and DR rats. These data suggest that cytolysin may be a mechanism by which Tc and NK cells damage B cells in vivo.

Dynamic 13C NMR analysis of oxidative metabolism in the in vivo canine myocardium

Oxidative metabolism in the in vivo canine myocardium was studied noninvasively using 13C-enriched acetate and non-steady state 13C NMR techniques. Under low workload conditions, the myocardium oxidized the infused [2-13C]acetate and incorporated the labeled carbon into the glutamate pool as expected. This conclusion stems from the rapid enrichment of the C-2, C-3, and C-4 carbons of glutamic acid both under in vivo conditions and in extracts. Surprisingly, [2-13C]acetate uptake was not observed at high workloads as reflected by an absence of glutamate pool enrichment at these rate pressure products. Rather, the myocardium selected its substrate from an endogenous pool. Since free acetate can directly cross the inner mitochondrial membrane and be converted to acetyl-CoA through acetyl-CoA synthetase, these results support workload-dependent regulation of substrate access to the mitochondrial CoASH pool. As such, we advance the hypothesis that the selection of substrate for condensation with CoASH and subsequent oxidation in the tricarboxylic acid cycle is regulated kinetically through the Km values of the appropriate condensation enzymes and through the absolute levels of free CoASH in the mitochondria.

Functional ecdysone receptor is the product of EcR and Ultraspiracle genes

Although the biological activity of the insect moulting hormone ecdysone, is manifested through a hormonally regulated transcriptional cascade associated with chromosomal puffing, a direct association of the receptor with the puff has yet to be established. The cloned ecdysone receptor (EcR) is by itself incapable of high-affinity DNA binding or transcriptional activation. Rather, these activities are dependent on heterodimer formation with Ultraspiracle (USP) the insect homologue of vertebrate retinoid X receptor. Here we report that native EcR and USP are co-localized on ecdysone-responsive loci of polytene chromosomes. Moreover, we show that natural ecdysones selectively promote physical association between EcR and USP, and conversely, that high-affinity hormone binding requires both EcR and USP. Replacement of USP with retinoid X receptor produces heterodimers with distinct pharmacological and functional properties. These results redefine the ecdysone receptor as a dynamic complex whose activity may be altered by combinatorial interactions among subunits and ligand.

Consumption of n-3 polyunsaturated fatty acid-enriched eggs and changes in plasma lipids of human subjects

The cholesterolemic effect of chicken eggs enriched with n-3 polyunsaturated fatty acids (PUFA) was investigated in healthy volunteers. Twenty-three male university students consumed two regular or n-3 PUFA-enriched eggs per day with their habitual diet for 18 days. Plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels were raised in subjects who consumed regular eggs but were maintained virtually unchanged in those who consumed n-3 PUFA-enriched eggs. Intake of two regular eggs a day did not affect plasma high-density lipoprotein cholesterol (HDL-C) and plasma triglyceride (TG) levels, but intake of two n-3 PUFA-enriched eggs a day resulted in a significant elevation in HDL-C (p < 0.05) and a reduction in plasma TG (p < 0.01). Consuming regular eggs tended to decrease both HDL-C/TC and HDL-C/LDL-C ratios, whereas consuming n-3-enriched eggs tended to increase them. The n-3 PUFA contents in plasma lipids of subjects who consumed n-3 PUFA-enriched eggs were also found to be elevated. These results demonstrate that the cholesterolemic property of chicken eggs can be modified by altering the fatty acid composition of yolk lipids.

Interactive intraoperative localization using an infrared-based system

We discuss new methods of localizing and treating brain lesions for both the conventional method of a base-ring fixed to the patient's skull (referred to as frame-based procedures) and the new method of frameless procedures (no base ring). Frame-based procedures are used for finding a precise instrument position during neurosurgical procedures, such as stereotactic biopsy of deep-seated lesions, placing electrodes for functional stereotaxis or catheters with radioactive seeds for brachytherapy, or even the placement of a stereotactic retractor or endoscope for removal or internal decompression of lesions. In such procedures, the intraoperative image localization of instruments becomes useful as it tracks instruments as they travel through the preplanned trajectory. Additional intraoperative digitization of surgical instruments, e.g., bipolar suction, biopsy forceps, microscope, ultrasound probe, etc, can be achieved during the stereotactic resection of eloquent areas or deep intracranial lesions by adding an infrared-based system. Frameless procedures broaden the range of surgical approaches, image guidance planning, and operative procedures, since no ring is attached to the patient's head which might interfere with the surgical approach, and offers logistic advantages in scheduling diagnostic studies. Frameless diagnostic studies employ anatomical markers and/or surface matching techniques for data registration in the computer software surgical preplanning program. This simplifies scheduling of the procedures since the image study does not need to be acquired the same day as surgery. Frameless diagnostic studies allow for the use of more than one type of imaging data for planning and optimization of surgical procedures, and greatly improve patient tolerance and comfort during these procedures and during surgery, as compared with frame-based procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

A graphical user interface to facilitate patient-specific drug dosing

This paper describes the development of a graphical user-interface (GUI) designed to facilitate the process of generating patient-specific drug doses using bayesian modelling software. The graphical user interface was developed in Visual Basic (Microsoft, Inc.) and runs under the Windows 3.1 (Microsoft, Inc.) operating system. Patient demographic data are stored in a relational database (Access, Microsoft, Inc.). The GUI and the database communicate via dynamic data exchange links. The largely object-oriented nature of the language allowed us to change the entire look and feel of the system with a few simple changes to the underlying code. Use of the relational database to store patient demographic information allows greater flexibility in searching for and displaying patient specific information. The GUI reduces the time required to enter data. The prototype has allowed us to experiment with different presentation methods, greatly improving the clinical acceptance of the dosing programs.

[Development of hybridomas secreting monoclonal anti-idiotypic antibodies that bear the internal image of the terminal trisaccharide of PGL-I]

Two hybridomas designated as F7B7 and F7B9 secreting monoclonal anti-idiotypic antibodies against terminal trisaccharide of PGL-I were developed by fusion of SP2/0 cells and spleen cells of BALB/c mouse immunized with mouse monoclonal anti-trisaccharide of PGL-I (MAb1-E10F1). To characterize the F7B7, the following results were obtained. First, F7B7 reacted with MAb1-E10F1 specifically. Secondly, the cross ELISA neutralizing tests gave positive results. The binding of anti-trisaccharide positive serum with trisaccharide (contained in semi-synthetic antigen, NT-O-BSA) was inhibited F7B7 and the degree of inhibition showed dose-dependent manner. The binding of anti-trisaccharide positive serum with F7B7 was inhibited by NT-O-BSA and the degree of inhibition also showed dose-dependent manner. It was concluded that the hybridoma F7B7 is able to secrete monoclonal anti-idiotypic antibodies that bear the internal image of trisaccharide of PGL-I. The potentials and advantages of monoclonal anti-idiotypic antibody F7B7 as surrogate antigen in the serodiagnosis of leprosy have been discussed.

[The antioxidant action of AH-9]

AH-9 is a compound with hypoglycemic action. AH-9 was also found to have antioxidant activity. The hemolysis, hemoglobin oxidation and lipid peroxidation of erythrocytes induced by hydrogen peroxide and Fe(++)-induced MDA formation of liver microsomes were inhibited by AH-9, and the activity of SOD and catalase were shown to be increased in normal and alloxan-diabetic mice after treatment with AH-9. The above results indicate that AH-9 might act as a scavenger of superoxide and might be useful for improving the pathophysiological state in diabetes mellitus and its complications.

[The hypoglycemic effect of AH-9]

AH-9 is an acylhydrazine compound with hypoglycemic effects in normal mice, alloxan-induced diabetic mice and spontaneously diabetic KK mice. In terms of equi-molar doses (0.3 mmol/kg po), AH-9 was found to be more potent than phenfornin and glicalazide (diamicron) in normal mice. Insulin resistance was shown to be improved in spontaneously diabetic KK mice and hydrocortisone-induced insulin resistant mice after treatment with AH-9. The LD 50 of AH-9 given orally to mice was found to be 956 mg/kg (about 18 times its effective dose). Studies on the hypoglycemic mechanism of AH-9 (insulin release, insulin receptor and post-receptor) showed that AH-9 did not influence serum insulin levels in mice. But, in in vivo experiments, AH-9 appeared to promote the capacity and affinity of insulin receptors in mouse liver plasma membranes. AH-9 was also found to antagonize the elevation of blood glucose level and liver glycogen content caused by alanine injection. AH-9 was shown to enhance the conversion of U-14C-glucose to 14CO2 in mouse epididymal fat tissue in vitro. According to the above results, the hypoglycemic action of AH-9 might be due to: 1) increasing the capacity and affinity of insulin receptors; 2) directly enhancing glucose aerobic oxidation; and 3) inhibiting gluconeogenesis.

Acute motor axonal neuropathy: a frequent cause of acute flaccid paralysis in China

In northern China, annual epidemics of acute-onset flaccid paralysis diagnosed clinically as Guillain-Barré syndrome have been recognized for at least 20 years. On the basis of an historical analysis of more than 3,200 patients, distinctive features include most cases occurring during the summer months among children and young adults, most of whom reside in rural areas. Of 90 patients with acute flaccid paralysis, 88 had a distinctive pattern that shares clinical and cerebrospinal fluid findings with demyelinating Guillain-Barré syndrome, but that differs from Guillain-Barré syndrome physiologically and pathologically. The clinical course is marked by rapidly progressive ascending tetraparesis, often with respiratory failure, but without fever, systemic illness, or sensory involvement. Cerebrospinal fluid is acellular, and elevations of protein content occur in the second or third week of illness. Electrodiagnostic studies show normal motor distal latencies and limb conduction velocities, but reduced compound muscle action potential amplitudes. Sensory nerve action potentials and, when elicitable, F waves are within the range of normal. Recovery is usually good. Autopsy studies have shown Wallerian-like degeneration of motor fibers. These studies establish that this is a distinctive syndrome, distinguishable from poliomyelitis and demyelinating Guillain-Barré syndrome.

Is atrial pacing needed for determination of coronary flow reserve by parametric imaging?

Heart rate changes during determination of coronary flow by parametric imaging may influence the flow measurement. Thus, the question is whether atrial pacing is mandatory for determination of coronary flow reserve (CFR) by this technique. CFR was calculated by digital subtraction angiography (parametric imaging) in 10 patients (8 with coronary artery disease and 2 control subjects) during sinus rhythm and during atrial pacing. Flow measurements were determined in the perfusion region of the left anterior descending and circumflex coronary artery, both at rest and after maximal coronary vasodilation with 10 mg intracoronary papaverine. CFR was defined as coronary flow during hyperemia divided by coronary flow at rest. Spontaneous heart rate was 71 +/- 15 min-1 at baseline, 73 +/- 15 min-1 after papaverine injection and 85 +/- 10 min-1 during atrial pacing. Heart rate variations during coronary arteriography were 4 +/- 3 min-1 at baseline and 5 +/- 4 min-1 after papaverine administration. CFR was 2.61 +/- 1.01 during sinus rhythm and 2.67 +/- 1.05 during atrial pacing. Mean absolute difference in CFR between sinus rhythm and atrial pacing was 0.31 +/- 0.31 (12 +/- 10% of CFR during pacing). Spontaneous heart rate variations during coronary arteriography are not associated with significant changes in CFR. Thus, atrial pacing is not mandatory for the determination of CFR by parametric imaging.

Schizophrenic delusions among Koreans, Korean-Chinese and Chinese: a transcultural study

In this transcultural study of schizophrenic delusions among Koreans, Korean-Chinese and Chinese, many delusions were shown to be different among the three groups in their frequency and content and the differences could be explained by sociocultural and political factors. Delusional themes sensitive to influence by sociocultural or political situations and changes seem to be 'family', 'love affairs', 'religious matters', 'economic matters', 'specific physical damage' and 'political themes.' Delusions about 'family', 'love affair', 'being raped', 'religious matters' and 'economic and business matters' were most frequent in Koreans. Delusions of 'blood-relatedness', 'longevity' and 'political themes' were most frequent in Korean-Chinese. Delusions of 'bloodsucking and brain or viscera extracted' and 'poison or being pricked by poisoned needle' were most prominent in Chinese.

New calcium-sensitive ligand for nuclear magnetic resonance spectroscopy

Fluorinated calcium-sensitive indicators such as 5,5'-difluoro-1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (difluoro-BAPTA) will often be less sensitive under in vivo conditions than gyromagnetic ratio considerations alone would have predicted. This is due to the very broad line widths displayed by these molecules within the living cell. In order to provide a spectroscopic alternative to these molecules, we have synthesized 13C-enriched 1-(2-aminophenoxy)-2-(2-aminoethoxy)ethane-N,N,N',N'-tetraac etic acid or AATA. The rationale for the design of this molecule was the increased signal to noise ratio available by selective detection of 13C-attached protons in AATA using proton-observe carbon-edited spectroscopy or multiple-quantum coherence. AATA has the advantage of increased number of detectable nuclei and narrow line widths. As such, it should provide a 6-10-fold improvement in the signal to noise ratio over existing fluorinated indicators. As a hybrid between EGTA and BAPTA, AATA should display intermediate pKa's, exchange rates, and KD values. We have measured pKa values of 5.94 +/- 0.05 and 9.03 +/- 0.05 for AATA. KD values of 350 +/- 80 nM and 6.6 +/- 2.0 mM were obtained for the AATA-Ca2+ and AATA-Mg2+ interactions, respectively, at 37 degrees C in 0.1 M KCl. As such, this new ligand displays the expected selectivity for Ca2+ over Mg2+. This new approach to detection of intracellular probes with NMR can be readily extended to other probes for intracellular ions, pH, and membrane potential. In addition, the move toward carbon-selected proton spectroscopy should also permit more flexibility in synthetic approaches since the strong electronegativity of fluorine often hampers synthetic design.

[The kinetic observation of serum ketone body levels in surgical patients receiving MCT or LCT emulsions]

The changes of serum beta-hydroxybutyrate concentrations in patients after receiving medium chain triglycerides (MCT) or long chain triglycerides (LCT) were studied. The patients were divided into two groups: in Group 1, the dose of fat was 0.14 g/kg.h for fat emulsion clearance test: and in Group 2, the dose was 0.06 g/kg.h for total parenteral nutrition (TPN) support. The beta-hydroxybutyrate concentrations were estimated by an enzymatic method using Sigma's beta-hydroxybutyrate kit (Sigma Diagnostics, MO 63178, USA). The normal range of beta-hydroxybutyrate concentration in 30 healthy Chinese subjects was 1.04 +/- 1.42 mg/dl (range 0-3.88 mg/dl). In Group 1, we found that the concentrations of beta-hydroxybutyrate rose steadily after fat emulsion infusion. The concentrations in the medium chain triglyceride group were higher than those in long chain triglyceride group. The elevated concentrations of beta-hydroxybutyrate gradually returned to normal levels when the emulsion infusion was stopped. In Group 2, the concentrations of beta-hydroxybutyrate in the patients were within the normal range.

Transforming growth factor beta 1 and adrenocorticotropin differentially regulate the synthesis of adrenocortical cell heparan sulfate proteoglycans and their binding of basic fibroblast growth factor

Adrenocortical differentiated functions are under the control of both endocrine hormones such as ACTH and local factors such as transforming growth factor beta (TGF beta) or basic fibroblast growth factor (bFGF). Besides their regulatory actions on the synthesis of corticosteroids, these two classes of factors also exert some important effects on the cellular environment. We have examined here the regulation by ACTH and TGF beta of adrenocortical cell proteoglycan synthesis and secretion. Under basal conditions, adrenocortical cells synthesized and secreted several species of sulfated proteoglycans, 80% of them being recovered in solution in the culture medium. When analyzed by ion exchange chromatography, the cell extracts and the media from cells metabolically labeled with 35S-sulfate were found to contain two and three species of radioactive sulfated proteoglycans, respectively. All species were proteoheparan-sulfates. Treatment of adrenocortical cells with TGF beta 1 or ACTH resulted in a significant increase of the incorporation of 35S into both secreted and cell-associated proteoglycans. ACTH stimulated more than three times the amount of secreted proteoglycans eluting from DEAE-Trisacryl as peak B, whereas TGF beta preferentially increased the amount of peak C. No important modification of the size of the synthesized proteoglycans was observed. The subpopulation of heparan sulfate proteoglycans capable to bind bFGF was also largely increased after ACTH or TGF beta treatment and paralleled the variation in overall proteoheparan sulfate synthesis. Thus those effects of TGF beta and ACTH on proteoglycan synthesis may participate in an increased ability of adrenocortical cells to bind and respond to bFGF.

Monitoring of serum markers for fibrosis during CCl4-induced liver damage. Effects of anti-fibrotic agents

Liver fibrosis was induced in rats by repeated peritoneal injections of carbon tetrachloride (CCl4) over a period of 2-11 weeks. Serum procollagen III peptide (SPIIINP), prolidase (SP) and alanine aminotransferase (SALT) levels were monitored during the period of induction. The extent of fibrosis was semi-quantitatively estimated after collagen staining, and the anti-fibrotic effects of 16,16-dimethyl prostaglandin E2 (DMPGE2), colchicine, and zinc sulphate were studied. SPIIINP and SP were increased the first 2 weeks after CCl4 administration and peaked at 6 weeks. Alterations in SPIIINP and SP correlated well to the semi-quantitative histological score of liver sections during the first 6 weeks, and SP was positively related to SPIIINP throughout the whole induction period. DMPGE2 decreased SPIIINP, SP and SALT significantly in addition to a markedly decreased formation of liver collagens. Colchicine had a similar but less dramatic effect, whereas zinc sulphate only reduced SPIIINP without influencing liver damage. In conclusion SPIIINP seems to be a valuable indicator of liver fibrogenesis, and SP may play a limited role in indicating accelerated collagen metabolism in the liver. DMPGE2 obviously inhibited the production of collagens induced by CCl4. Colchicine also had an apparent effect on liver fibrosis, whereas zinc sulphate merely seemed to postpone it.

[Reduction mammaplasty]

Twenty-eight breasts of 15 patients with macromastia underwent reduction mammaplasty from 1982 to 1989. We followed up these patients postoperatively for 6 months to 7 years. The follow-up time for 8 patients was over 1 year, and 4 patients over 5 years. And 3 patients labored and lactated. These 15 patients were satisfied with this operative results. The operative technology was based on Pitange's method. This method improved the site of the nipple, transposition of nipple-areola complex, and design of dermal pedicle, so that it had better effects in the breast shape, breast fixation and incision scar concealed. We suggest that the purpose of macromastia treated in reducing volume, improving breast shape, preserving lactating function. This paper also discusses the methods for nipple site, nipple-areola complex transposition, breast resection and mastopexy.

Ion-exchange chromatography (IC) in the determination of serum transition metals and its clinical application

The reproducibility of ion-exchange chromatography (IC) (Dionex Bio-LC) in measuring the serum transition metals Cu and Zn was found to be fairly good (CV = +/- 2.1% and +/- 2.7% within runs, and +/- 2.5% and +/- 4.3% among runs for Cu and Zn, respectively). For clinical application, sera from 20 normal volunteers and 20 patients with cancers of the digestive tract (10 early and 10 late stage cases) were analyzed. The means of serum Cu (15.54 +/- 0.31 mumol/L) and serum Zn (14.84 +/- 0.31 mumol/L) in normal volunteers were very close to the values previously determined by atomic absorption spectrophotometry in our laboratory. In the group of late stage cancer patients, the means of serum Cu (24.18 +/- 0.63 mumol/L) and the Cu/Zn ratio (1.97 +/- 0.07) were significantly elevated (P < 0.01), while serum Zn (13.01 +/- 0.61 mumol/L) was remarkably decreased (P < 0.05). There were no significant changes of serum Cu, Zn and Cu/Zn ratio in early stage cancer patients. It is concluded that the IC method is rapid, accurate, sensitive, relatively simple and could be useful in diagnosing late stage cancers of the digestive tract.