Monitoring of filarial antigens in jirds and patients after treatment

We developed a sandwich ELISA with monoclonal antibodies to monitor filarial antigens in animals and patients after infection and treatment. Levels of antimicrofilarial antibodies and parasite antigens were measured periodically in 40 B. malayi infected jirds. In all animals L3 HC11 antigen was detected earlier than Mf ES34 antigen, while antimicrofilarial antibodies appeared much more slowly. These serologic changes precede the onset of patent infections. After 3 courses of treatment with DEC and M170, the levels of parasite antigen in sera and of Mf in peritoneal cavities were monitored in 23 infected jirds. In 8 jirds Mf became negative, no adult worms were found in 7 jirds and a single degenerating female worm was present in 1 jird. ES34 and HC11 were undetectable in 8/8 and 6/8 necropsy sera. Mf persisted in 11 animals, 9 jirds were necropsied, 8 contained adult worms. Detectable levels of ES34 or HC11 antigen were present in 7/9 and 8/9 from these animals. In sham-treatment, few changes were noted in control animals. Thus, parasitological findings at necropsy are correlated with the results of antigen detection assay. We analyzed serial serum samples from 32 bancroftian microfilaremia collected 1-42 months after DEC therapy. Mf resolved rapidly in all treated individuals. ES34 disappeared faster than HC11, 3 months after treatment. Levels of ES34 and HC11 antigens remained detectable or rising after treatment in 8 and 10 individuals. Four patients' Mf recurred 20-42 months after treatment. These findings show that the remaining or a rise in serum levels of antigen after therapy predicts recurrent microfilaremia in patients and additional treatment is needed.

[Study on the bias axis stress-strain relationship of the human mandible]

This paper presents our study on the bias axis elastic properties of the human mandible. The elastic coefficients were determined by the composite materials mechanical testing methods. From these values the "technical constants" were calculated to be: EL = 18.823GPa, ET = 12.777GPa, GLT = 5.564GPa, vLT = 0.302, vTL = 0.205. Variation of elastic constants of the human mandible with the orientation to its long axis was investigated. A brief description of the variation law is given. The bias axis stress-strain relationship of the human mandible is established. The data indicate that the human mandible is a living, anisotropic and nonhomogeneous composite biomaterial. Its mechanical properties have a close relation to its location, orientation and structure.

[The changes of viscoelastic properties of whole blood in patients with chronic cor pulmonale]

The changes of blood viscoelasticity and apparent viscosities at low shear rate (0.512 S-1) and high shear rate (51.2 S-1) were studied in 61 patients with various severity of chronic cor pulmonale (CCP). The relation between blood viscoelasticity and apparent viscosities and PaO2 and PaCO2 was investigated and the data were collected before and after treatment. Grouped data: Group 1. A total of 61 patients with CCP were studied, 10 of them died during hospitalization. Sixty-one patients at the acute stage were divided into mild, severe and dead sub groups. Twenty-nine patients were improved after treatment. Group 2. Control group (74 normal people) matched group 1 in sex and age. The results demonstrated that eta 0.512, eta 51.2 and eta' were slightly increased in the mild group, but HCT, eta 0.512, eta 51.2, AI, eta' and eta" were elevated more significantly in the severe group. All variables mentioned above of died patients were elevated more remarked than that of the mild group. HCT, eta" in dead patients were slightly higher than those in severe group (P less than 0.05-0.01). It was clear that the more severe the patient, the more increased the hematocrit and RBC aggregation, the less the RBC deformability. HCT would be elevated when PaO2 was below 8 kPa (60 mmHg) and the HCT, eta 0.512, eta', eta" increased significantly (P less than 0.05-0.01) when PaCO2 was over 6.65 kPa (50 mmHg). There was a positive linear correlation between eta 0.512 and PaCO2.(ABSTRACT TRUNCATED AT 250 WORDS)

[Gas chromatograms of fatty acids from Rickettsia and their similarities]

Fatty acid compositions of 7 strains of Rickettsia were analyzed by a on-line GC/MS system. These strains were R. prowazekii E, R. conorii Simko, R. rickettsii R, R. sibirica Barbash and 246, R. sinkiangensis Jinghe, and R. heilungkiangensis 54. The samples were purified by means of the concentrated salt-ether method. There were about 50 peaks in the fatty acid profiles, and 16 of these peaks were determined, i.e. C22:0, C19:0, C18:0, C18:1, C18:2, C17:0, C16:0, C16:1, 3-OH-C14:0, C15:0, C14:0, C13:0, 2-OH-C12:0, C12:0, 2-OH-C10:0, and C11:0. The major fatty acids were the saturated straight chain acids (e.g. C16:0, C18:0, C14:0) and the unsaturated straight chain acids (e.g. C18:1, C18:2, C16:1). Similarities of fatty acid profiles of tested strains were discriminated by the improved Kulik-Vincent method. The result showed that the KV's coefficient of strains Jinghe and 246 was 97.0%, and the KV's coefficient of strains 54 and the others was 81.6-94.6%.

[An experimental study on hepatic arterial embolization with 131I-MMC-GM]

We designed a new gelatin microsphere (GM, 65 micron in diameter), which could combine with mitomycin C and 131I. The test in vitro showed that the GM had excellent drug release effect. Hepatic arterial embolization was carried out in 6 dogs with 131I-MMC-GM. The dogs survived from 4 to 28 days before being killed. Scintigraphy indicated that high radioactivity was concentrated in the liver, but was very low in the blood and thyroid. Pathologic study found that the GM was trapped in hepatic arterioles. The GM was eliminated by foreign body giant cells and the lumen of arterioles was occupied by granulations 14-28 days after operation. 131I-MMC-GM is a multiple anticancer agent which can exert triple action of targeting chemotherapy, internal radiotherapy and arterial embolization.

Myocardial dysfunction and norepinephrine release in the isolated rat heart injured by electrolysis-induced oxygen free radicals

In the present investigation, we used electrolysis as a source of oxygen free radicals to test their possible role in norepinephrine release, as well as in the mechanism of cellular injury, cardiac dysfunction and arrhythmias. In the isolated rat heart perfused under constant pressure, according to the Langendorff technique, electrolysis of the Krebs-Henseleit solution (10 mA d.c. current for 1 min) produced myocardial irreversible dysfunction within 5 min. Fifteen minutes after electrolysis, significant falls in the left ventricular pressure (from 87.5 +/- 6.8 to 33.7 +/- 5.2 mmHg), dP/dt max (from 1230 +/- 90 to 375 +/- 59 mmHg/s), heart rate (from 287 +/- 18 to 119 +/- 13.5 beats/min) and coronary flow (from 14.8 +/- 9 to 3.4 +/- 1.7 ml/min) were observed, along with an increase in left ventricular end diastolic pressure from 10 to 50 +/- 3.5 mmHg (n = 8, P less than 0.01). AV conduction block and/or sinus bradycardia were noted in all preparations. An increase in norepinephrine washout from 298.5 +/- 84 at baseline to 610 +/- 110 pg/min/g 5 min after electrolysis was measured (n = 8, P less than 0.05) and a 44.8 +/- 9.2% and 35 +/- 7.5% reduction, respectively in right and left ventricular tissue norepinephrine content was also found at 30 min (n = 5, P less than 0.05). Pretreatment of the hearts 10 min before electrolysis and throughout the experimental period by superoxide dismutase (SOD; 100 U/ml), catalase (150 U/ml), a combination of SOD + catalase or mannitol (50 mM) partially blocked the deleterious effect of free radicals and permitted a functional recovery of 50 to 60%, mannitol being the more potent protective agent. Furthermore, these scavengers also significantly reduced norepinephrine washout.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of microinjection of tutin into nucleus tractus solitarius region on the morphology of neural tissue of this area in rabbit]

Four hours after unilateral microinjection of tutin (10 micrograms) into the NTS region, the nervous tissue surrounding the center of microinjection showed the following morphologic changes: 1. Under the light microscopic examination (n = 5), the neuronal body showed chromatolysis and the nuclear basophilia enhanced in about 17% of the neurons, the lacunae of neuropil distended and gave a "spongy" appearance. The neurons with lesion mingled with the normal ones in the absence of distinct demarcation. 2. Under the electron microscopic examination (n = 3), the cisterns of rough endoplasmic reticulum distended, and the nuclear electron density increased on account of the increased nuclear chromatin in the affected cells. The organelles of dendrites decreased or disappeared; the neuroglia looked edematous. There were only a few axons which looked edematous in the neuropil. Microinjection of the same volume (1 microliter) of NS into the other side of NTS region in the same rabbit didn't show any sign of damage as those described above. Thus, our preliminary results suggest that tutin might damage the soma and dendrites of some neurons, and therefore, it might be a neuroexcitotoxin.

Hypothyroidism increases serotonin turnover and sympathetic activity in the adult rat

Adult, male Sprague-Dawley rats underwent surgical thyroidectomy (Tx) or sham surgery. In all three experiments from which data are reported, a 3-week recovery period was allowed. In experiments I and II, baseline measurements of colonic temperature (Tc) and urinary norepinephrine excretion (NE) were obtained, and both variables were monitored daily for the duration of the studies. After baseline measurements, half of each surgical group was given either triiodothyronine (T3) or vehicle injections subcutaneously; in experiment I replacements continued for 1.5 days, while in experiment II T3 replacement continued for 3.5 days. Rats were decapitated at the end of each experiment and serotonin (5-HT) turnover was measured in brainstem. Serotonin turnover in rostral and caudal brainstem was increased with Tx (p less than 0.05). Increased turnover in caudal brainstem was normalized by T3 only in experiment II. Similarly, decreased Tc and elevated NE with Tx were normalized in experiment II but not in experiment I. In experiment III, NE measurements normalized on a creatinine excretion basis indicated that increased NE is evident with Tx, irrespective of normalization procedure. Significant correlations between 5-HT in caudal brainstem and metabolic correlates of sympathetic function, concurrent normalization of NE and 5-HT in caudal brainstem, plus work from other laboratories describing sympathoexcitatory serotonergic neurons located in the caudal brainstem suggest that the central and peripheral changes in the hypothyroid rat are causally related.

Basic determinants for FM responses in the inferior colliculus of rats

The response of 835 click-sensitive neurons in the inferior colliculus (IC) to ramp frequency modulated (FM) tones was studied in the anaesthetized rat. More than 70% of the cells were sensitive to the FM sound, and over 25% were "FM specialized". Systematic variations of the stimulus parameters showed that sweep velocity, sweep range, and intensity of the FM signal were the 3 basic determinants for the unit response. For an "FM specialized" cell, the response pattern to each of the parameters was either monotonic or bell-shaped. The population statistics of response patterns to the FM parameters, including the tuning factors, were generated. A stimulus domain was proposed to represent the "receptive space" of the FM cells.

[Interleukin 1 beta gene expression by mouse glomerular mesangial cells]

Interleukin 1 beta (IL-1 beta) plasmid DNA was isolated and purified with alkaline lysis method and equilibrium centrifugation in cesium chloride. IL-1 beta plasmid RNA was cut by restriction endonucleases EcoRI and XbaI, and after that it was 1 loaded in 0.75% low-melting-temperature agarose and underwent electrophoresis. 1.2 Kb DNA fragments were extracted from gel and for further purification it was used as IL-1 beta cDNA probe. RNA from mouse glomerular mesangial cells, tubular epithelial cells and P388D, cells was cut with EcoRI separately and then hybridized in dot blots with alpha 32P labeled IL-1 cDNA probe. The dot blot autoradiograph showed expression of the IL-1 beta gene in mesangial cell and P388D1 cell but showed no expression in epithelium. These results not only identified the specificity of IL-1 beta probe but also suggested that the local production of IL-1 beta may be important in the pathogenesis of glomerulonephritis.

Supercondensed structure of plasmid pBR322 DNA in an Escherichia coli DNA topoisomerase II mutant

An unusual structural component, supercondensed pBR322 DNA, has been found in plasmid pBR322 DNA samples isolated from a DNA topoisomerase II mutant of Escherichia coli, SD108 (topA+, gyrB225). The supercondensed pBR322 DNA moved faster than supercoiled pBR322 DNA as a homogeneous band in agrose gels when the DNA samples were analysed by electrophoresis. The mobility of the supercondensed DNA was not substantially affected by chloroquine intercalation. The supercondensed pBR322 DNA migrated as a high density "third DNA band" when the samples were subjected to caesium chloride/ethidium bromide gradient equilibrium centrifugation. The unusual pBR322 DNA visualized by electron microscopy was a globoid-shaped particle. These observations suggest that the pBR322 plasmid can assume a tertiary structure other than a supercoiled or relaxed structure. DNA topoisomerases may be involved in the supercondensation of plasmid DNA and chromosomal DNA.

[Protective effects of gypenosides on experimental myocardial infarction]

In the model of myocardial infarction produced by occlusion of left anterior descending coronary artery (LAD) in rabbit, gypenosides (GP 100 but not 50 mg/kg, ip) reduced myocardial infarct size and decreased serum free fatty acid (FFA). In rat model of myocardial infarction, GP and the fractions of GP of non ginsenosides (FGNG) both in dose of 100 mg/kg, ip, protected significantly myocardial superoxide dismutase (SOD) activity and decreased the myocardial malondialdehyde (MDA). The results indicate that the protective effect of GP on myocardial infarction may be correlated with its prevention of myocardial lipid peroxidation, and attributed to the amelioration of FFA metabolic deterioration.

[Nutritive physiology of Psoralea corylifolia L]

Our study has shown that P. corylifolia absorbs and accumulates N2 and K2O most speedily in the periods of branching, flowering and fruiting, while P2O5 in the period of full flowering and fruiting. P2O5 is accumulated mainly in the seed and K2O in the stem. The nutriment accumulation is positively correlated with that of dry substances. To produce 100 kg of P. corylifolia an absorption of 10.59 kg of N2, 3.68 kg of P2O5 and 10.21 kg of K2O is needed.

[Acute morphological changes in guinea-pig cochlea following electrical stimulation]

The acute morphological changes of intracochlear electrical stimulation were studied in 42 guinea-pigs, which were divided into six groups. The electrode was implanted into the cochlea 1.5mm deep, and the cochlea was stimulated with intensities of 216 microA, 432 microA, 648 microA, 864 microA and 1080 microA for six hours. Morphological changes observed in the stimulated ears ranged from hair cell, nerve cell and supporting cell degeneration to complete destruction of the basilar membrane and organ of Corti overlying the electrode. These changes occurred at current intensities ranging from 432 to 1080 microA and were conspicuously absent in the implanted but unstimulated control ears and in the ears with 216 microA stimulation. Our observations also demonstrate that 432 microA stimulation can change the structure of the cochlea.

[Effect of seed soaking in plant hormone and trace element fertilizer on the growth of Psoralea corylifolia L]

Our study shows that seed soaking in triacontanol, ammonium molybdate and gibberellin can promote the growth of P. corylifolia, reduce its premature flower and fruit drop, raise the fruit-bearing rate by 6.5-17.4%, and fruit-bearing number by 21.6-28.4%, so as to increase the yield per unit area by 31.5-34.8%. Seed soaking in naphthylacetic acid and boric acid does not give such a marked effect.

[Effects of proteolytic enzymes on demineralization of enamel]

Papain, trypsin and collagenase were used in the experiment for the study of their effects on the demineralization of enamel surface by organic acids in vivo. No effect of any of the enzymes was observed. The use of papain and trypsin in treating tooth surfaces in vitro, no matter whether sodium bisulfite was used, showed no effect on the demineralization of the enamel by mixed organic acids. But, by the analysis of amino acids in the enzyme solutions before and after treating tooth surface, it was shown that some proteinous substances were destroyed. Accordingly, it can be suggested that the enzyme takes no part in the destruction of the inorganic tooth substance.