[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.