A sensitive fluorometric method for measurement of vascular permeability in spinal cord injury

A sensitive fluorometric method was modified for the evaluation of drug action upon vascular permeability in rat spinal cord injury. Fluorescein isothiocyanate-conjugated dextran (FITC-D MW 71,200), used as a macromolecular tracer, was injected iv 2 hours before sacrifice. The optimal pH for FITC-D fluorescence was 8.2. The recovery in spinal cord was 101.4 +/- 4.0% (mean +/- SD). The extent of FITC-D extravasation, expressed as the vascular injury index (VII), was increased in proportion to the trauma force. The peak of VII after trauma was at 2 hours. This fluorometric method is sensitive, simple, and reliable for evaluation of drug effects upon vascular permeability in CNS trauma.

[Studies on nutrition source of seeds germination of gastrodia elata B1]

The seeds of Gastrodia elata lack an endosperm and other stored nutrition and thus do not easily germinate. Armillaria mellea inhibit germination of the seeds, which exist in a type of symbiotic relationship with fungi. The nutrition necessary for germination is derived from Mycena osmundicola invading cells of the embryo. The tree leaves provide a good medium for Mycena osmundicola growth and an indirect nutritional source for germination.

[Experimental study on cyclosporin A (CsA) acting on rejection of heterolamellar corneal transplantation]

The experiment involved the transfer of lamellar corneas (0.3mm thick and 10mm diameter central epithelium with stroma) from fresh bovine eyes onto rabbits eyes.

RESULTS

group 1, control, (4 rabbits), the donor corneas remained transparent for up to 7-10 days on the recipient rabbit eyes. After that time, all animals in this group rejected their grafts promptly. They showed markedly circumcorneal congestion, edema and vascularization of the cornea. Histopathology: There are apparently cellular infiltration of leukocytes in the grafts, and graft bed of the cornea, which are found also in the iris. Group 2: 3 rabbits were treated with 1% CsA in castor oil, 5 times per day. After 16 days, One of three rabbits showed mild rejection. Group 3: 4 rabbits were treated with CsA, I.M. 15 mg/kg/D. None has any immunological response to the grafts. The histopathology of group 2 and 3 shows no cellular infiltration, except one. CsA can 1. inhibit the rejection of the heterograft. 2. prolong the survive of the heterograft. 3. inhibit the vascularization. 4. has less side effects.

[Effect of phenolic resin fluid on the dentin resistance]

SEM observation was made in the experiment to analyze the ultrastructure of resinified dentin. Phenolic resin fluid permeates in to the dentinal-tubule and set in it. The permeability of this agent was also able to permeate into intercellular substance and changed the appearance of inter-weaved fibril to the condition of agent had set. According to the Fracture Mechanics, it was not beneficial to resist the fracture progress if the microspace had been fulfilled by the agent. The tensile stress of resinified dentin was 387 kg/cm2, which was 30 kg/cm2 lower than that of unresinified-dentin.

Tetramer-dimer conversion of phosphofructokinase from Thermus thermophilus induced by its allosteric effectors

Phosphofructokinase (PFKase) was purified from an extreme thermophile. Thermus thermophilus. Allosteric natures of T. thermophilus PFKase is similar to those of Bacillus stearothermophilus PFKase, that is, hyperbolic plots of the activity versus concentration of fructose 6-phosphate (F6P) were changed into a sigmoidal shape by the addition of phosphoenolpyruvate (PEP), while further addition of ADP caused it to revert to a hyperbolic shape. The native T. thermophilus PFKase has an Mr of 148,000 consisting of four 36,500 subunits. However, it exists as a two-subunit form of Mr 74,000 in the presence of PEP. The two-subunit form was catalytically inactive. The four-subunit enzyme was regenerated by addition of either F6P or Mg.ADP, or by removal of PEP from the solution. This reversible dissociation was observed within a wide range of pH (6.5 to 8.4) and temperature (4 degrees C to 65 degrees C). Thus, unlike PFKase from other sources, the allosteric kinetics of T. thermophilus PFKase can be explained well, at least qualitatively, by the dynamic equilibrium between the active four-subunit form and inactive two-subunit form that is modulated by PEP, F6P and Mg.ADP. Parallel suppression of the PEP-induced conversion in molecular form and kinetics by high concentrations of sulfate and phosphate supports the above explanation. Also, the observation that the degree of PEP inhibition was dependent on the protein concentration of the PFKase in the assay solution is consistent with the presence of this equilibrium.

Identification and characterization of a regulated promoter element in the epidermal growth factor receptor gene

We have identified a 36-base-pair proximal element (-112 to -77 relative to the AUG translation initiation codon) in the epidermal growth factor receptor 5' region that functions as a promoter; mediates inductive responses to epidermal growth factor, phorbol 12-myristate 13-acetate, and cyclic AMP; and acts in an orientation-independent manner. This region functions as an enhancer when transferred to a heterologous promoter containing a TATA box. Mutations within the 36-base-pair region alter function as assayed by reporter gene expression in recipient cells. A protein has been identified that demonstrates appropriate binding specificity to mutant DNA sequences that correlates with promoter activity observed in vivo. On the basis of DNA binding characteristics and size, the identified protein appears distinct from several previously identified transcription factors known to bind to G+C-rich regions.

[Cytological observation on hyphae invading Mycena osm undicola in the process of seed germination of Gastrodia elata Bl]

In order to obtain the nutrition necessary to sprout, Gastrodia elata seeds depend on digesting a kind of fungi (Mycena osmundicola Lange). Hyphae are enclosed and digested by embryonic cytoplasm after M. osmundicola penetrates the embryo through suspensor cells, and then meristem cells begin to divide. The digested hyphae penetrate into large cells to be further digested. The body of the embryo then enlarges and germinates under meristem cells using the nutrition thus obtained.

[A simplified polygraphic method for studying sleep in the rat]

Experiments were performed on 10 healthy Wistar rats with chronically implanted electrodes for the recording of electrocorticogram (ECoG), electro-oculogram (EOG), and electromyography (EMG). All the rats were prepared for the implantation of recording electrodes under 5% Ketamine (100 mg/kg i.p.) anesthesia. Four to six days after operation, the rat was put in an apparatus which was designed specifically sensitive to detect the movement of the animal without electrode on the body so that electroactogram (EAG) could be recorded readily. One group of experiment animal (n = 5), recorded ECoG, EAG, EOG and EMG simultaneously, was compared to another group (n = 5), recorded ECoG and EAG simultaneously. The results of experiments indicate that the ECoG, recorded from the the mesial frontal and occipital areas, have certain characteristics during different sleep phases, and the characteristics for classifying sleep phases by the two kinds of somnopolygram are similar. Therefore, simultaneous recording of the ECoG and EAG can be used to discriminate the sleep phases in the rat. In this way, the somnopolygraphic recording method for studying sleep in the rat would be simplified.

[Effects of fungi and its liquid extract on seed germination of Dendrobium hancockii Rolf]

The experiment revealed that several species of fungi isolated from the protocorms of Orchidaceae notable promote the seed germination of Dendrobium hancockii. The seed germination rate amounts to over 20% when the seeds are incubated with fungi, but zero without incubation. Seed germination rate ranges from 40 to 70% when the incubation is affected in liquid extract of the cultural products of fungi, but the growth of protocorms and seedlings of Dendrobium hancockii is slower in liquid extract of fungi than on mycolia.

[Determination of primary metabolic products of fungi promoting seed germination of Gastrodia elata Bl. and other Orchidaceae medicinal plants]

The contents of amino acids, protein, water-soluble sugar, reducing sugar and microelements in seven strains of seed-germination-promoting fungi were determined. It was found that the contents of primary products were different in these fungi. In the light of physiological characteristics of seed germination, the action mechanism of the products in promoting seed germination was discussed.

[Sedative-hypnotic effect of caulis Polygoni multiflori decoction]

The sedative-hypnotic effect of Caulis Polygoni multiflori decoction (CPMD) was studied by the rolling cylinder method in mice and by the somnopolygraphic recording method in rats. The result from the rolling method in mice showed that CPMD (9g/kg) did have synergic action with the subthreshold hypnotic dose of sodium pentobarbital (20mg/kg). The result from the somnopolygraphic recording experiment showed that the immediate hypnotic effect of an effective dose of CPMD (20g/kg) was basically similar to that of diazepam (5mg/kg) used under the same experimental condition, chiefly an increase in the duration of slow wave sleep phase (SWS) and a decrease in the duration of paradoxical sleep phase (PS). By the end of a three-day session in dose of twice a day the hypnotic effect appeared more prominent and the reduction of SWS latency became significant.

[Selection of the germination strain of Mycena osmundicola Lange in Gastrodia elata Bl. seeds]

By successive selection and comparison these seeds are higher in germination rate, faster in protocorm growth and higher in yield of Gastrodia elata. It is evident that Mycene osmundicola is one of the best strains in Gastrodia elata germination fungi.

[Antitumor action of lignum sappan]

The aqueous extract of lignum sappan can kill cell lines of HL-60, K562, L929 and Yac-1 at the concentration of 2 microliters/ml. The survival time of mice bearing EAC is increased by 185% (P less than 0.01) by ip 0.2 ml/mouse x 7d. The three-stage sequential test standard can be passed smoothly.

[Relation of changes in plasma TXB2 PGF1alpha and differentiation of signs and symptoms in traditional Chinese medicine in severe icteric hepatitis]

Clinical observations and experimental studies were made in 52 cases of chronic cholestatic hepatitis, 30 cases of chronic severe hepatitis, 30 healthy control persons, and 30 animals with experimental intrahepatic cholestasis. The results were as follows: Plasma TXB2 and PGF1 alpha were higher than their normal values both in cases of chronic cholestatic hepatitis and in cases of chronic severe hepatitis (P less than 0.01), the ratio of TXB2 and PGF1 alpha was normal in cases of chronic severe hepatitis and lower than normal value in cases of chronic cholestatic hepatitis (P less than 0.01). The cases were divided into 4 types (hepatitis due to blood stasis and blood heat, blood stasis and blood heat accompanying symptoms of fluid retention in the epigastrium, damp-heat, and composite factors) according to differentiation of symptoms and signs on the basic theories of TCM. Significant difference was found in TXB2, PGF1 alpha, PGF1 alpha/TXB2 and bilirubin when compared with each other in the 4 types of hepatitis patients (P less than 0.01). Bilirubin, TXB2, PGF1 alpha and PGF1 alpha/TXB2 in the survivors became normal or close to normal after they were treated with blood-cooling and circulation-promoting Chinese herbal medicine and prescriptions by changing their dosages according to differentiation of symptoms and signs on the basic theories of TCM. The therapeutic effect of prescription II was more satisfactory than that of prescription I. Changes of plasma TXB2 and PGF1 alpha in the experimental animals were more significant than those both in the control group and in the group treated with prescriptions I and II (P less than 0.01), but in the liver only the ratio of TXB2 and PGF1 alpha was lower than that in normal animals (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

[Relation of changes in plasma cAMP, cGMP and the clinical conditions, pathology and the type of traditional Chinese medicine in 50 cases of chronic severe icteric hepatitis]

Plasma of cAMP and cGMP in 30 cases of chronic active hepatitis (group of cholestatic patients) as well as in 20 cases of chronic hepatitis with submassive or massive necrosis (group of chronic severe hepatitis patients) were studied with 125I-marked radioimmunoassay. 50 cases with their serum bilirubin levels higher than 171 mumol/L were selected as subjects for this study. Among them, 42 were diagnosed as hepatitis B, 6 as coinfection of hepatitis A and B. According to differentiation of symptoms and signs of TCM, 24 were diagnosed as simple hepatitis due to blood stasis and blood heat, 17 as hepatitis due to blood stasis and blood heat accompanying symptoms of Yang deficiency of the Spleen and Kidney. 20 healthy persons were selected as controls. The results were as follows: cAMP was 56.82 +/- 25.54 ng/L and 80.32 +/- 20.73 ng/L, and cGMP was 9.07 +/- 6.56 ng/L and 19.49 +/- 9.34 ng/L in the group of cholestatic patients and in the group of chronic severe hepatitis patients respectively. Both were higher than those in the control group whose cAMP was 14.12 +/- 3.25 ng/L and cGMP was 5.87 +/- 1.44 ng/L (P less than 0.01). Increase in cGMP and decrease in the ratio of cAMP and cGMP in the cases accompanying symptoms of Yang deficiency of the Spleen and Kidney were much higher than those in the other two types of hepatitis patients (P less than 0.01 and 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Light-evoked changes in extracellular calcium concentration in frog retina

Light-evoked changes in extracellular Ca2+ concentration were recorded with Ca2(+)-selective microelectrodes in the retina of the frog eyecup. A Ca-decrease at light onset and offset was found in the inner plexiform layer, and its properties are consistent with it resulting from Ca2+ influx into activated neuronal terminals. In the subretinal space, a Ca-increase at light onset and a Ca-decrease at offset were observed, and these likely arise directly from photoreceptors. A slower ON Ca-decrease was also seen here. Because it survives pharmacological isolation of the photoreceptors from post-synaptic interactions, but not physical isolation of the retina from the pigment epithelium, this component probably depends on pigment epithelial activity.

[The properties of dentin and resinified dentin in the tensile test]

The purpose of this study is to evaluate the effect of resinifying therapy to the hard tissue of tooth by using measurement of the tensile strength. The fresh extracted maxillary anterior teeth having been cleaned and sterilized were divided into two groups. The control group was placed into 9% N-saline solution of 37 +/- 1 degrees C. The experimental group was treated with resinifying therapy. The tensile specimens were shaped by turning in a lathe until it satisfied the tensile test requirement of Mechanics of Materials except that they were hollow. A set of special split jig was made for this test. Instron Universal Testing Machine was used for measuring the load on the specimens. The loading speed was 0.05 mm/min. The straining meter was used to measure the tensile strain. The result revealed that tensile strength of resinifying dentin was little lower than that of unresinified dentin. The resinified dentin didn't increases stiffness or brittleness.

Transformation of Xenorhabdus nematophilus

The ability of Xenorhabdus nematophilus 19061/1 to be transformed by pHK17 plasmid DNA was studied and optimized. A number of factors, including culture conditions, stage of growth, transformation buffer pH, cation type and concentration required for the production of competency, washing, heat shock conditions, and cell-DNA ratio, were found to affect transformation significantly. On the basis of these observations, a procedure for the routine transformation of X. nematophilus 19061/1 at frequencies of 1 X 10(5) to 10 X 10(5) transformants per microgram of pHK17 plasmid DNA was developed. Maximum transformation was obtained when cells which had reached the mid- to late-logarithmic growth phase (total counts, 2.5 X 10(8) to 5 X 10(8) cells per ml) within 4.5 to 5.5 h were washed once in cold transformation buffer before they were suspended in the same buffer to 0.1 of their original volume. The highest transformation was obtained when dimethyl sulfoxide was added in two steps to the cells immediately before the DNA was added, after which the cell-DNA mixtures were incubated for 30 min on ice before they were given a 3-min heat shock at 37 degrees C. Following these treatments, the transformed cells were incubated in L broth-60 mM CaCl2 for 1 h before they were plated onto selective medium. We also were able to transform X. nematophilus 19061/1 with plasmid pBR325, and we transformed other species of Xenorhabdus with several common plasmids.

Mucosal homeostasis: role of interleukins, isotype-specific factors and contrasuppression in the IgA response

Oral ingestion of antigen elicits immune responses at mucosal sites where humoral immunity is largely due to antibodies of the IgA isotype. This is often accompanied by suppression of systemic responses to the same antigen, a state termed oral tolerance. This IgA response is regulated by interactions between T cell subsets found at IgA inductive tissues, i.e., the gut-associated lymphoreticular tissue (GALT) or Peyer's patches (PP). PP T helper (Th) cells support IgA responses, and interleukins 5 (IL-5) and IL-6 can augment secretion of this isotype. Subsets of Th cells may also express Fc receptors for IgA (Fc alpha R) and secrete Fc alpha R as an IgA-binding factor (IBF alpha). Membrane-derived Fc alpha R is a glycoprotein of 38,000 M.W. and this molecule induces selective increases in IgA secreting cells (as determined by the ELISPOT assay) in PP B cell cultures. Fc alpha R+ T cell lines have been shown to secrete IBF alpha as well as IL-5 both of which promote IgA synthesis. Recombinant IL-5 (rIL-5) and rIL-6 induce IgA synthesis mainly by PP B cell blasts, and principally act on surface IgA-positive (sIgA+) B cells for these responses. Another form of mucosal regulation is provided by T contrasuppressor (Tcs) cells, which abrogate oral tolerance when adoptively transferred to mice and restore systemic responsiveness to the antigen sheep erythrocyte (SRBC). Tcs cells from mice systemically primed with SRBC support IgM and IgG subclass responses, while Tcs cells from orally primed mice support IgM, IgG subclass and IgA anti-SRBC responses. These Tcs cells are CD3+, CD4-, 8- and are antigen-specific. These regulatory cells may use the gamma-delta (gamma-delta) form of T cell receptor for antigen recognition.

Localization of the beta-like globin gene cluster and the genes for parathyroid hormone and c-Harvey-ras 1 to region q14----q21 of rabbit chromosome 1 by in situ hybridization

The rabbit beta-like globin gene cluster (HBBC), comprised of epsilon-, gamma-, delta-, and beta-globin genes (HBE, HBG, HBD, and HBB, respectively), has been mapped to chromosome 1, region q14----q21, by in situ hybridization using probes for rabbit HBE and HBG. Probes for the human parathyroid hormone gene (PTH) and the Harvey-ras 1 protooncogene (HRAS1) also localize to this region by in situ hybridization. Thus, these genes are syntenic in lagomorphs as well as four other mammalian orders (primates, rodents, carnivores, and artiodactyls). The mapping data in rabbits provide further evidence that this synteny is strongly conserved in the evolution of mammalian chromosomes.

High K BaTiO(3) films from metalloorganic precursors

Crack-free and dense BaTiO(3) films 4 to 8 mum thick were prepared by spinning a solution of metalloorganic precursors onto an appropriate substrate, and firing and annealing the film in air at certain temperatures to obtain appropriate grain sizes. The electrical properties of the films were studied as a function of grain size, temperature, frequency, and DC bias. Films with a grain size of 0.2 mum showed ferroelectric properties similar to bulk BaTiO(3).

Histochemistry and electron microscopy in the diagnosis of small mucous cells in carcinoma of the stomach

One hundred and two cases of poorly differentiated adenocarcinoma were obtained from 71 surgical and 31 biopsy specimens of the stomach. These tumours produced both intracellular and extracellular mucins, which were demonstrated to be neutral mucins, N-acetyl sialomucins, sulphomucins and O-acetyl sialomucins. The majority of tumours (85.3%) secreted two or more kinds of mucins simultaneously, but only a small proportion (14.7%) produced a single kind of mucin. Ultrastructurally, three types of mucin granules were identified; these differed in shape and density. Tumour cells containing intracellular mucins or mucin granules were designated as mucous cancer cells and further subdivided into small, large and goblet mucous cells; tumour cells having neither mucins nor glandular differentiation were designated as undifferentiated cancer cells. These histochemical distinctions, supported by the electron microscopical observations, may be useful to demonstrate early malignant foci in gastric biopsies.

PbTiO(3) films from metalloorganic precursors

Ferroelectric PbTiO(3) films 0.5- to 2.0-mum thick were prepared by the metalloorganic decomposition (MOD) process using multilayer spinning with firing temperatures of 490-630 degrees C. The temperature dependence of the dielectric constant was found to be a function of the c/a ratio, which could be modified by control of either the single-layer thickness or the strength of the electric field during film preparation near the Curie temperature. The films were near theoretical density and defect-free over 2 cmx2 cm areas.