[Method of producing fusarin C in perlite-liquid culture medium]

For researching the biosynthesis labelled Fusarin C(Fc) by Fuscarium moniliforme, a more quick and convenient method of Fusarin C production and purification were established, and a good liquid culture medium consisted of different kinds organic matters (hydroxy proline, sucrose and glycerin), inorganic salts and perlite replaced corn grit medium. The perlite-liquid culture medium inoculated with the strain of F. moniliforme yields 936mg Fc/kg organic matter with in 14 days of incubation at 28 degrees C. As compared with the corn grit medium, the amount of Fc from perlite-liquid medium was more than that from corn grit medium (831mg Fc/kg corn grit). In all experiments both thin-layer chromatography and high-pressure liquid chromatography were used to confirm the presence of Fc. parameters which were important for the optimal biosynthesis of Fc included hydroxy proline and sucrose concentrations, incubated time/temperature and amount of perlite. The 40g of sucrose/L liquid culture was optimal concentration for Fusarin C production. Of three contained N-matter tested, hydroxy proline was the best sources of N-atom for Fusarin C. Under the absence of hydroxy proline, the Fc wasn't synthesized in perlite-liquid culture medium by F. moniliforme. A culture time/temperature study of Fc production was done, and the optimal Fc amounts was synthesized after incubation for 14 days at 28 degrees C on perlite-liquid culture medium.

Excitatory amino acid signal transduction in the hippocampus: role of noradrenergic afferents and nitric oxide in cGMP increases in vivo

Previous studies have demonstrated that excitatory amino acid (EAA)-dependent increases in cerebellar cGMP are dependent upon the prior activation of nitric oxide (NO) synthase. Additionally, the actions of NMDA, but not kainate or quisqualate, in elevating cerebellar cGMP have been shown to be dependent upon intact noradrenergic innervation of the cerebellum. In the current study we extended these observations to the hippocampus and again found that EAA-dependent increases in hippocampal cGMP also involve prior formation of NO. And as in the case of the cerebellum, NMDA-dependent increases in hippocampal cGMP involve prior release of norepinephrine which in turn apparently activates an alpha 1-adrenergic receptor to elicit cGMP increases. In toto, these data suggest that a key role of NMDA receptors in these brain regions is to presynaptically regulate the release of norepinephrine, thereby modulating the tone of this monoaminergic system. This may be a general principle which needs experimentation in other terminal fields of noradrenergic pathways.

ACTH hypertension in the rat: role of sodium chloride

Adrenocorticotrophin (ACTH) produces adrenally dependent increases in both blood pressure and salt (NaCl) appetite in the rat. The present study examines the effect of free access to a high intake of NaCl on ACTH hypertension in the rat to test the hypothesis that high NaCl intake would amplify the rise in blood pressure. Either water or 1%NaCl were offered to sham or ACTH treated Sprague-Dawley rats. Subcutaneous injections of synthetic ACTH (0.5 mg/kg/day) for 10 days caused large increases in the intake of both 1%NaCl (+240 +/- 6 ml/day) and water (+45 +/- 4 ml/day), urine volume (1%NaCl + ACTH +182 +/- 4 ml/day, ACTH + water +36 +/- 2 ml/day), adrenal weight (ACTH + water 176 +/- 18, ACTH + 1%NaCl 367 +/- 129 mg/100 g body weight) and maximum systolic blood pressure (SBP) (ACTH + water +18 +/- 5 mmHg; 1%NaCl + ACTH +16 +/- 3 mmHg). Some ACTH + 1%NaCl rats developed severe edema. Thus, free access to NaCl in ACTH treated Sprague Dawley rats did not potentiate the hypertension, but was associated with edema in some animals.

Effects of methylguanidine on sodium and organic ion transport

We studied the acute effect of methylguanidine (MG), a suspected uremic toxin that accumulates in renal failure, on p-aminohippurate (PAH) and tetraethylammonium (TEA) uptake in rabbit kidney slices, on Na+,K+ ATPase activity in the microsomal fraction of rabbit kidneys, and on transepithelial active Na transport across toad skin. MG at concentrations ranging from 0.05 (similar to that reported in uremic patients) to 1.0 mM does not affect the organic anion (PAH) uptake, although it exhibits a concentration-dependent inhibition of organic cation (TEA) uptake. MG at concentrations from 0.05 to 5 mM had no effect on kidney Na+,K+ ATPase activity or on active transepithelial Na transport across toad skins when applied to the outside bathing solution; however, MG (greater than 1 mM) stimulated Na transport when applied to the inside bathing solution. These results are not consistent with the hypothesis that MG is a potential uremic toxin that causes the natriuresis and other toxic effects. However, long-term toxic effects of MG on the kidney were not assessed in the present study.

Evidence that M3 muscarinic receptors in rat parotid gland couple to two second messenger systems

The binding affinities of muscarinic antagonists were compared with their abilities to block carbachol (CCh)-mediated stimulation of Ca2+ mobilization and inhibition of isoproterenol-elicited adenosine 3',5'-cyclic monophosphate (cAMP) accumulation in rat parotid cells. The binding of [3H]quinuclidinyl benzilate (QNB) to membranes was inhibited by antagonists with the following potencies (dissociation constant, nM): atropine (1.1) approximately 4-diphenylacetoxy-N-methylpiperidine methbromide (4-DAMP) (1.6) much greater than pirenzepine (136) greater than 11-[[2-[(diethylamino)methyl-1-piperidinyl]-acetyl]acetyl]-5,11- dihydro-6H-pyrido[2,3-b][1,4]-benzodiazepine-6-one (AF-DX 116) (5,293). AF-DX 116 blocked Ca2+ mobilization and inhibition of cAMP accumulation with low affinities [inhibitory concentration at 50% (IC50) = 3150 and 6,528 nM, respectively], whereas 4-DAMP blocked these responses with considerably higher affinities (IC50 = 4.3 and 11.4 nM, respectively). Schild plots of 4-DAMP and AF-DX 116 antagonism of CCh-stimulated inositol trisphosphate accumulation showed inhibitor constant (Ki) values of 0.85 and 1,585 nM, respectively, whereas Schild plots of 4-DAMP, AF-DX 116, and methoctramine antagonism of CCh-induced inhibition of cAMP accumulation showed Ki values of 1.3, 1,585, and 2,754 nM, respectively. Preincubation of cells with 0.1 mM 3-isobutyl-1-methylxanthine did not prevent the capacity of CCh to inhibit cAMP accumulation. Pertussis toxin blocked the CCh-elicited and Gi-mediated inhibition of cAMP formation. Northern blot analysis showed the presence of mRNA for the M3, but not for the M2, subtype in parotid gland. An immunochemical procedure using m1-m5 specific antibodies was performed in parotid membranes and showed that the m3 receptor accounts for 93% of precipitable receptors. These data suggest that M3 receptors in the rat parotid are coupled to both the stimulation of Ca2+ mobilization and the inhibition of cAMP accumulation.

Epidermal growth factor elevates intracellular pH in chicken granulosa cells by activating protein kinase C

Previous studies from our laboratory have demonstrated that epidermal growth factor (EGF), induces intracellular alkalinization in chicken granulosa cells by activating a sodium-dependent and amiloride-sensitive Na+/H+ antiporter. In the present investigation we have examined the possible involvement of protein kinase C (PKC) in the regulation of intracellular pH (pHi) by EGF in chicken granulosa cells. Intracellular pH in granulosa cells obtained from the two largest preovulatory follicles was determined spectrofluorometrically using the dye 2',7'-bis-(carboxyethyl)-5(6)-carboxyfluorescein. The resting pHi was 6.81 +/- 0.01 (n = 30) when the extracellular pH and sodium concentration were 7.3 and 144 mM, respectively. 12-O-Tetradecanoyl-phorbol-13-acetate (TPA; 50-400 ng/ml) and 1-oleoyl-2-acetylglycerol (OAG; 1-75 micrograms/ml) mimicked the actions of EGF by inducing a concentration-dependent increase in pHi which reached a maximum of 0.25-0.30 pH units. 4 alpha-Phorbol 12,13-didecanoate, a phorbol ester with no tumor promoting activity had no effect on pHi. Cytosolic alkalinization was observed within 10 min of the addition of each agent and increased over the 60-min observation period. Like EGF-induced cytosolic alkalinization, the increases in pHi in response to TPA or OAG were dependent on the presence of sodium concentration and were inhibited by amiloride, an inhibitor of the Na+/H+ antiporter. The effects of EGF, TPA, and OAG were attenuated by the PKC inhibitors 5-isoquinolinylsulfonyl-2-methyl piperazine and trifluoperazine. Down-regulation of granulosa cell PKC by pretreatment with TPA (200 ng/ml) for 2.5 h inhibited EGF-, TPA-, and OAG-induced cytosolic alkalinization. The effects of maximally stimulatory concentrations of EGF and TPA on cytosolic alkalinization were not additive. The increases in pHi induced by TPA and OAG, but not by EGF, were dependent on the presence of extracellular Ca++. These studies suggest that the EGF-induced intracellular alkalinization in chicken granulosa cells involves a PKC-mediated activation of the Na+/H+ antiporter.

Isolation and characterization of mannose 6-phosphate/insulin-like growth factor II receptor from bovine serum

A convenient means was devised for the purification of milligram quantities of a soluble form of the mannose 6-phosphate/insulin-like growth factor II receptor (Man-6-P/IGF II receptor). The receptor was purified to near homogeneity from bovine serum by affinity chromatography on agarose-pentamannosephosphate in the absence of detergent. Approximately 2.5 mg of receptor were obtained from 500 ml of fetal calf serum. The concentration of receptor in serum decreased sharply with development. Fetal calf serum Man-6-P/IGF II receptor was immunologically similar to detergent-solubilized, membrane-bound Man-6-P/IGF II receptor from bovine liver. N-Terminal sequence analysis revealed that the purified serum receptor, but not the solubilized, membrane-associated receptor, contains stoichiometric amounts of bound IGF II. The results of sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and gel chromatography studies suggest that the fetal calf serum receptor (in contrast to the solubilized, membrane-bound bovine testis receptor) does not aggregate. The affinity of the fetal calf serum receptor for bovine testis beta-galactosidase approximated one-half that observed for solubilized, membrane-bound bovine testis receptor.

Electroencephalography, magnetic resonance imaging and pathology in patients treated surgically for temporal lobe epilepsy

In a consecutive series of 40 patients selected by EEG studies for surgical treatment of temporal lobe seizures, magnetic resonance imaging showed structural lesions in 25% and signal abnormalities, usually in the mesial temporal region, in another 35%. Pathological changes included structural lesions in over 30% of patients and sclerosis of the amygdala in almost half of the series. These findings further substantiate the implication of the amygdala in the pathogenesis of temporal lobe seizures with automatism and amnesia.

Development of an antiserum against m3 muscarinic receptors: distribution of m3 receptors in rat tissues and clonal cell lines

A synthetic oligopeptide (QCDKRKRRKQQYQQRQSV) corresponding to a carboxyl-terminal sequence of the rat m3 receptor (amino acids 561-578) was coupled to carrier proteins and used to generate a polyclonal antiserum. This serum selectively immunoprecipitates at least 90% of the m3 receptors expressed by A9 cells transfected with the cDNA encoding the m3 muscarinic receptor but does not precipitate receptors from cells transfected with cDNA encoding m1, m2, m4, or m5 receptors. Using this m3 antiserum, the density of m3 receptors in various regions of rat brain was quantified. Areas expressing the highest density of m3 receptors are the cortex, hippocampus, striatum, and olfactory tubercle, with 232 fmol/mg, 197 fmol/mg, 140 fmol/mg, and 130 fmol/mg, respectively. Hindbrain regions (i.e., cerebellum, thalamus/hypothalamus, and pons/medulla) expressed fewer m3 receptors, both as a percentage of total muscarinic receptors (5-6%) and in terms of absolute receptor density (12-70 fmol/mg). A panel of subtype-selective antisera (m1, m2, and m3) was used to determine receptor distribution in several peripheral tissues of the rat (lung, ileum, and bladder). The m2 receptor subtype constitutes the majority of total receptors in the bladder (86%), lung (91%), and ileum (69%). The m3 receptor was found at lower densities in these tissues (5-11%), whereas the m1 receptor is present in highest amounts in the ileum (17%). Human clonal cell lines, in which regulation of muscarinic receptors has been commonly studied, were also examined. The SK-N-SH neuroblastoma line, which has been reported to express M3 receptors, on the basis of pharmacology and molecular size, was found to express a mixture of subtypes (m1 = 31%, m2 = 21%, m3 = 43%). Interestingly, SH-SY-5Y and SH-IN cells, both derived from SK-N-SH cells, exhibit predominantly m3 receptors (74% for SH-SY-5Y; 58% for SH-IN), with lower levels of m1 and m2 receptors (5% and 8% for SH-SY-5Y; 4% and 23% for SH-IN, respectively.) Another commonly studied cell line, 132-1-N1 astrocytoma cells, reportedly expressing M3 receptors, based upon mRNA measurements and second messenger linkage, also expresses a predominance of m3 receptors (91% of total). This m3-selective antiserum should prove useful not only for localizing and quantifying m3 muscarinic receptors but also for examining mechanisms involved in the regulation of receptor expression in human tissues or animal models of disease, as well as in cell culture.

Expression of two different forms of fibroblast growth factor receptor 1 in different mouse tissues and cell lines

The fibroblast growth factor receptors (FGFRs) form a multigene family of at least four members, all having extracellular regions consisting of either two or three immunoglobin-like (Ig-like) domains. By RNase protection analysis we have analyzed the expression of FGFR-1 mRNA in various tissues and cell lines and demonstrated that all of the cell lines studied expressed at least two different forms of the FGFR-1 at similar levels. Although muscle and heart express forms having either two [FGFR-1 short (FGFR-1S)] or three [FGFR-1 long (FGFR-1L)] Ig-like domains, the developing brain and adult brain express only mRNA encoding the longer form. The two forms of the receptor were characterized further by stably introducing expression vectors expressing them into Rat-2 fibroblasts and FDC-P1 myeloid cells. Treatment of the transfected Rat-2 cells with acidic FGF (aFGF) or basic FGF (bFGF) resulted in focus formation. The transformed phenotype was observed even without addition of ligand after growth in culture for greater than 2 months. Cross-linking of 125I-labeled bFGF (125I-bFGF) to Rat-2 cells expressing either FGFR-1L or FGFR-1S yielded two similar complexes of 150 and 110 kDa. Although Rat-2 cells expressing FGFR-1L yielded similar complexes with 125I-labeled aFGF (125I-aFGF), only the 150-kDa complex was formed with cells expressing FGFR-1S. The 150-kDa complex was also observed when 125I-aFGF or 125I-bFGF was cross-linked to FDC-P1 cells expressing FGFR-1L. Significantly, these complexes were only observed when heparin was present in the cross-linking reaction. FDC-P1 cells expressing FGFR-1 bound aFGF and bFGF with high affinity but only in the presence of heparin. The factor dependence of these cells could be switched from interleukin 3 to FGF in the presence of heparin.

[Effects of phencyclidine on rabbit basilar artery in vitro and rabbit cerebral blood flow in vivo]

The effect of phencyclidine [1-(1-phenylcyclohexyl)piperidine, PCP] on rabbit basilar arteries was studied with an in vitro model of ring segment arteries. PCP 0.05-500 mumol.L-1 caused vasoconstriction of basilar arteries in a concentration-dependent manner. Its maximal effect (Emax) was 94 +/- 21 mg and the concentration causing half maximal effect (EC50) was 25 +/- 18 mumol.L-1. PCP 0.01-10 mumol.L-1 also concentration-dependently augmented the vasoconstriction induced by electric stimulation in rabbit basilar arteries. Its Emax was 91 +/- 18 mg and EC50 was 0.27 +/- 0.17 mumol.L-1. The effects of PCP on mean arterial blood pressure (MABP) and heart rate (HR) of rabbits were observed. PCP iv 4 mg.kg-1 reduced MABP from 14.3 +/- 0.8 to 12.2 +/- 1.0 kPa and HR from 300 +/- 0 to 278 +/- 5 bpm in 5 min. Using the technique of radionuclide imaging in rabbit brain in vivo, we studied the effect of PCP on cerebral blood flow. After iv PCP 4 mg.kg-1, the tp of radiocerebrogram was increased from 4.5 +/- 1.1 to 6.1 +/- 1.0 s, the tg of radiocerebrogram was increased from 11.7 +/- 0.6 to 18.2 +/- 3.3 s and the rate of clearance was decreased. After iv PCP 2 mg.kg-1, only tg increased from 12.6 +/- 2.1 to 15.9 +/- 0.6 s. Hence PCP increased the transit time of nondiffusible indicators (99mTc) through the cerebral circulation. These results suggest that PCP causes constriction of basilar artery and slows down the cerebral blood flow.

Epidermal growth factor elevates intracellular pH in chicken granulosa cells

Many bioregulators, such as epidermal growth factor (EGF), induce intracellular alkalinization by activating a membrane bound Na+/H+ antiporter. The present studies were designed to examine the influence of EGF on intracellular pH (pHi) in chicken granulosa cells. pHi in granulosa cells from the two largest preovulatory follicles of hens was determined spectrofluorometrically using the dye 2',7'-bis(carboxyethyl-5(6)-carboxyfluorescein. The resting pHi was 6.81 +/- 0.006 (n = 30) when the extracellular pH and sodium concentration (Na+o) were 7.3 and 144 mM, respectively. EGF (5-100 ng/ml) induced a concentration-dependent increase in pHi, which reached a maximum of 0.217 +/- 0.009 pH units at a concentration of 100 ng/ml EGF. Cytosolic alkalinization was observed within 10 min of the addition of EGF and lasted over the 60 min observation period. The increase in pHi was dependent upon the presence of Na+o, since the EGF effect was attenuated when Na+o was substituted with equimolar concentrations of nonpermeant choline chloride. The EGF-induced pHi change was also inhibited by amiloride, dimethyl amiloride, and ethylisopropyl amiloride, inhibitors of the Na+/H+ antiporter. The alkalinization effect of EGF was mimicked by transforming growth factor-alpha but not by insulin, insulin-like growth factor-I, or transforming growth factor-beta. These studies suggest for the first time that intracellular alkalinization resulting from activation of the Na+/H+ antiporter may be a part of the transmembrane signaling pathway in the action of EGF on chicken granulosa cells.

Distribution of m2 muscarinic receptors in rat brain using antisera selective for m2 receptors

The DNA fragment encoding the third intracellular loop of rat m2 muscarinic receptor was fused to the gene for staphylococcal Protein A. The resultant fusion protein, expressed in bacteria, was purified via IgG affinity chromatography and used as an antigen to raise a polyclonal antiserum. Chinese hamster ovary cells transfected with cDNA coding for a single muscarinic receptor subtype were used as tissue sources to screen antisera. The antiserum was shown to immunoprecipitate quantitatively (greater than 90%) m2 receptors but not to precipitate m1, m3, m4, or m5 receptors. Additionally, immunoprecipitation by m2 antiserum could be inhibited by protein containing the third intracellular loop of the m2 receptor. This selective m2 antiserum was then used to study the distribution and density of m2 receptors in rat brain and heart. In agreement with previous studies, m2 receptors were found to be abundant in heart and comprise at least 92% of the total muscarinic receptor density. Hindbrain, brain stem, and midbrain regions such as cerebellum (75%), pons/medulla (70%), and thalamus/hypothalamus (43%) are also enriched in m2 receptors. In contrast, forebrain regions contain markedly lower percentages of m2 receptors, with cortex expressing 20%, hippocampus 19%, striatum 12%, and olfactory tubercle 20% of the total receptor density. Although the density of m2 receptors expressed as a percentage of total varied considerably from brain region to brain region, the absolute density of these receptors appeared relatively uniform throughout the brain. This study demonstrates that a gene fusion system can be used for efficient antibody production. The use of similar fusion protein antisera directed against other subtypes of muscarinic receptors should prove useful in future studies on regulation, function, and structure of muscarinic receptors.

Synthesis of (+/-)-N-2-methylpropyl-N-1'-methylacetonyl-nitrosamine

N-2-methylpropyl-N-1-methylacetonyl-nitrosamine (NMAMPA), first isolated from moldy and normal foods, was synthesized by chemical means. The structure and molecular weight of the synthetic NMAMPA were elucidated by spectrometry. A combination of spectral and chromatographic data indicated that the synthetic NMAMPA is identical to that obtained naturally. Synthetic NMAMPA is a racemic modification, and a carcinogen which can induce esophageal and forestomach cancer in rats.

[Experimental research of the effect of polysaccharides in semen Ziziphis Spinosae and Ziziphis Spinosae on enhancing the immune function of mice injured by radiation]

This article surveys the pharmacological effect of the polysaccharides in Semen Ziziphis Spinosae and Ziziphis Spinosae. The result shows that oral administration of this polysaccharide (0.1g/kg/d) can strengthen the immune function of cells nd body fluids and to a certain extent protect mice from radioactive injuries.

[Studies of pickled vegetables and cause of esophageal cancer in Linxian. II. Determination of nitrosamines and their precursors]

Pickled vegetables are daily food consumed in the high-risk areas for esophageal cancer in China. We analyzed the nitrosamine content of Linxian pickles by GC/TEA and found that trace amounts of six nitrosamines (NDMA, NDEA, NMBA, NMAMBA, NDPA, NPYR) were present, with the highest concentrations being NDMA and NDEA (1.7 and 1.9 micrograms/kg wet weight respectively). The average level of nitrosamine precursors, such as nitrate (111.22 mg/L), nitrite (0.152 mg/L) and secondary amines (4.223 mg/L), in pickled vegetables were determined, and their pH values ranged from 3 to 5.

[A study on the male DNA special restricted fragment of bovine]

Bkm, which is related to sexes, is a satellite DNA of the female snake. After the genomic DNA of bovine was digested by Pst I, it was hybridized with Bkm sequence probe (p184) and subcloned in the vector pUC19. Recombinants were identified by the colony in situ and Southern blot hybridization. When we determined genomic DNA of bovine using the male DNA fragment, it was observed that the pattern of hybridization was different because of different sexes. The results showed that we could identify the sex of bovine by Southern blot hybridization with recombinants of male DNA special restricted fragment of bovine origin.

[Endoscopic retrograde cholangiopancreatography in children]

Endoscopic retrograde cholangiopancreatography (ERCP) was performed less in children than in adults. Twenty-seven children, aged from 56 days to 14 years (average 6 years), received ERCP from August 1989 to December 1990. The cannulation into the papilla of Vater was successful in 24 children (88.9%) and their pancreaticobiliary ductal system was visualized clearly. Congenital biliary dilatation (CBD) was diagnosed in 16 patients and other biliary disorders in 8 patients. The APBD was confirmed in almost all CBD patients, showing a close etiological relation. It was concluded that ERCP is helpful to diagnose and differentiate pediatric biliary diseases and to study the etiology and pathophysiology of CBD.

Role of the sympathetic nervous system in the onset of hypertension in the rat: the effect of 6-OH-dopamine

1. The effect of chemical sympathectomy with 6-OH-dopamine (6-OHDA) on the onset of adrenocorticotrophin (ACTH)-induced hypertension was examined in Sprague-Dawley rats (n = 23). 2. 6-OHDA injection produced a fall in systolic blood pressure (SBP) from 100 +/- 5 mmHg control to 74 +/- 4 mmHg post-6-OHDA Treatment Day 1 (P less than 0.001), but did not alter food or water intake, urine volume or electrolyte excretion. 3. Compared with sham injection, ACTH-treated rats showed an increase in blood pressure (sham: 98 +/- 7 mmHg; ACTH: 123 +/- 9 mmHg on Treatment Day 10; P less than 0.01), loss of bodyweight, and increases in water intake and urine volume. 4. The magnitude of the blood pressure rise on ACTH was greater in 6-OHDA-treated rats than in intact control rats. Metabolic changes were similar. 5. Chemical sympathectomy with 6-OHDA did not delay or block the onset of ACTH hypertension in the rat.

[An investigation on the resources of medicinal fungi in Sichuan]

This paper reports the classification, distributional traits, new distribution, specific species of medicinal fungi, as well as the status of anticancer medications and edible and medicinal fungi in Sichuan. Rational suggestions have been made with regard to the cultivation, development and utilization of those important species with proven curative effect.

[A study on components and compound prescription of huangqin decoction]

The results obtained from the pharmacological experiments have preliminarily demonstrated that the compound prescription is better than its individual component drug in the range and potency of pharmacological activities. In the prescription Radix Scutellariae plays a principal role in pharmacological effects. Radix Scutellariae and Radix Paeoniae Alba can potentiate each other. Radix Glycyrrhizae and Fructus Jujubae in the compound prescription also exhibit biological activities to some extent. The relieving effect of the prescription for spasm and pain may result from the synergistic interaction between Radix Paeoniae Alba and Radix Glycyrrhiza, and the heat clearing and diarrhea stopping action is due to the biological activity of Radix Scutellariae.

The chemiluminescence of amides and monoacyl hydrazides based on firefly dehydroluciferin

Monoacyl hydrazides based on 5-methyldehydroluciferin and simpler analogs have been synthesized; they proved to be chemiluminescent on treatment with a strong base in DMSO in the presence of oxygen. The light emitters in these cases appear to be the corresponding carboxylate ions; a pathway involving an oxidative decarboxylation was eliminated as a possibility by consideration of the fluorescence wavelengths of the corresponding oxyluciferins. A reaction mechanism for the luminescence involving the possible intermediacy of an azadioxetane is proposed. The corresponding amides were also synthesized; they proved to be equally chemiluminescent to the hydrazides in the dehydroluciferin series.

Expression of normal and cystic fibrosis phenotypes by continuous airway epithelial cell lines

Continuous epithelial cell lines from individuals with cystic fibrosis (CF) and normal controls are required to understand the genetic and cellular defects in CF. We used retroviruses to transduce SV40 large T antigen into nasal epithelial cells. Transformed continuous cell lines were isolated that expressed epithelial markers, cytokeratin, and tight junctions. Northern blot analysis shows that all of the cell lines express the putative CF gene mRNA. Studies of transepithelial electrolyte transport show that CF and normal cell lines develop a transepithelial electrical resistance. Normal but not CF cell lines secreted Cl- in response to agonists that increase cellular levels of adenosine 3',5'-cyclic monophosphate (cAMP) (isoproterenol, forskolin, and a membrane-permeant analogue of cAMP) or in response to a tumor-promoting phorbol ester that activates protein kinase C. In contrast, the Ca2(+)-elevating agonist bradykinin and the Ca2+ ionophore A23187 stimulated secretion in both normal and CF cell lines. The continuous cell lines we have produced maintain their proper phenotypes and will serve as useful tools in understanding the pathophysiology of CF.

[Posterior scleral reinforcement operation in the high myopia with macular degeneration]

The authors performed posterior scleral reinforcement operation on 23 cases of high myopia with macular degeneration. One eye underwent surgery and the another eye served as control. Follow-up period ranged from 3 to 24 months. It was found that the corrected vision and refractive degree of the operated eye maintained the original levels and that the control eyes tend to become worse during the follow-up periods. It was also observed that the blood circulation of the macular area of operated eye seemed to be improved, and the bioelectricity was activated. No serious complications were found. Therefore the authors pointed out, for high myopia patients, if the condition advanced constantly, the posterior scleral reinforcement operation is a method of choice before other better therapeutic methods are established.

[Simultaneous determination of brucine and strychnine in semen Strychni by dual wavelength spectrophotometry and studies on processing principles of semen Strychni]

The paper reports the experimental result of the simultaneous quantitative determination of strychnine (ST) and brucine(BR) in Semen Strychni by dual wavelength spectrophotometry. The result shows that there are some deviations in the official method, because the wavelength combination might not have been chosen rightly and the correct coefficient is inconsistent with the facts. We have made a study of the thermal stability of ST and BR, too. On this basis a baking principle for Semen strychni is spelt out.

[Reperfusionable focal cerebral ischemia in rats]

Reperfusionable focal cerebral ischemia by embolization to the middle cerebral artery with nylon thread adhered to sponge was studied in rats. It was divided into 2 groups: permanent embolization and embolization for 3 hours. Neurological symptoms, degree of brain swelling and size of cerebral infarction of these animals were observed. The laboratory statistics was no difference between the two groups. But it was found in pathological specimens that infarction area were limited in the basal-ganglion with perivascular hemorrhage in 3 rats after reperfusion. Establishment of the model, symptoms of rats, results of laboratory and it's clinical significances were discussed.

The aggregation and dissociation properties of a low molecular weight mannose 6-phosphate receptor from bovine testis

The aggregation state of low molecular weight mannose 6-phosphate receptor from bovine testis was determined in membrane preparations and in purified soluble preparations. The effect of aggregation on binding of the receptor to immobilized pentamannose 6-phosphate was also examined. Nonreducing SDS-PAGE followed by immunoblotting revealed that interchain disulfide bonds exist in detergent-solubilized and purified receptor preparations, but not in membrane-associated receptor. Reduction of the receptor with dithiothreitol abolished its ligand binding activity and drastically altered its ability to bind antibodies. The results of receptor crosslinking and molecular sieving chromatography studies suggest that the receptor exists in membranes as a noncovalently linked dimer and in solution as oligomeric forms, largely as a tetramer. The formation of the tetramer is affected by the concentration of the receptor, but not by its solubilization from membranes with detergent, nor by the presence of mannose 6-phosphate. Mono-, di-, and tetramer forms of 125I-labeled receptor were separated by molecular sieving chromatography and examined for their ability to bind to immobilized ligand, agarose-pentamannose-phosphate. The order of binding observed was tetramer greater than dimer greater than monomer. Binding of the monomer and dimer to immobilized ligand was dependent on the presence of divalent cations while the tetramer had little requirement for divalent cations.

[Conformational changes of rat liver fatty acid binding protein induced by long chain fatty acid]

Rat Liver fatty acid binding protein (FABP) has been purified to homogeneity by the procedures including Sephadex G-100 and DEAE-cellulose column chromatography. FABP was resolved into two peaks of A and B by DEAE-cellulose column chromatography. Each of these fractions exhibited apparent homogeneity upon polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate with a molecular weight of 16,000 daltons and amino acid analysis of these fractions has revealed that they are identical protein. However, upon isoelectric focusing on polyacrylamide gel, the isoelectric (pl) points were differed considerably showing microheterogeneity. In the present investigation, one isoform (pl = 5.0) of FABP was purified by a successive DEAE-cellulose column chromatography and used for the subsequent experiments of fatty acyl-protein interactions. When the final FABP preparation was partly freed of fatty acids by a mild delipidation technique using Lipidex, the pl shifted toward higher regions of 7.0. However, the pl of the delipidated FABP turned to the original 7.0 by recombining fatty acids. On the other hand, the secondary and tertiary structures were also significantly changed by delipidization, which have been demonstrated by circular dichroism (CD) and nuclear magnetic resonance (1H-NMR) spectroscopy. Furthermore the structural properties of the delipidated FABP also could be restored by recombining fatty acid. These findings suggested that the weakly bound fatty acids are responsible for the functional capacity of the FABP by virtue of changing the protein conformation.

Interaction of heptanol and pressure on sodium and chloride transport by toad skin

We examined the interaction of heptanol and hydrostatic pressure on Na+ and Cl- transport in isolated toad skin. In the presence of Cl-, heptanol decreased short-circuit current (Isc) and total transepithelial resistance (Rt). However, in the absence of Cl- in the mucosal bath, heptanol increased Rt, although it retained the same inhibitory effect on Isc. When transepithelial active Na+ transport was blocked by amiloride, heptanol had no effect on Isc whether or not Cl- was present, whereas it decreased the shunt resistance (Rs) only in the presence of Cl- in the mucosal bath. Moreover, this effect of heptanol on Rs was significantly smaller in the presence of diphenylamine-2-carboxylate (DPC), a known Cl- channel blocker. Pressure also decreased Isc through inhibition of active Na+ transport, but it increased Rs. When heptanol and pressure were applied together, their inhibitory effects on Isc were additive, but their effects on Rs were antagonistic. Furthermore, when a transepithelial Cl- current was produced by reducing the Cl- concentration of the serosal bath, heptanol stimulated this current, which was reversibly inhibited by pressure or DPC addition to the mucosal bath. When the heptanol-stimulated Cl- current was first inhibited by pressure, subsequent DPC addition had less or no effect. These results suggest that one site of an antagonistic interaction of heptanol and pressure in toad skin is an apical membrane Cl- conductance.

Radiograph ordering: agreement between the triage nurse and the physician in a pediatric emergency department

We hypothesized that the triage nurse in a busy pediatric emergency department (ED) could accurately order radiographs, ultimately reducing patient waiting time. Protocols utilized to reduce patient waiting time are of importance in busy emergency departments. All patients registering at the ED of the Children's Hospital in a one-week period were entered into the study. The triage nurse documented whether they would send the patient for a radiograph, if allowed to, and were asked to designate a specific radiograph. The radiographs that were actually ordered by the physicians were subsequently obtained from radiology records. Data were analyzed for agreement beyond chance (kappa), positive (PPV) and negative predictive values. The results showed excellent agreement for extremity radiographs and poor agreement for nonextremity radiographs.

[Studies on pickled vegetables and cause of esophageal cancer in Linxian. I. Experiments on carcinogenicity of pickled vegetables]

Pickled vegetables are a traditional daily food served in several parts of China where esophageal cancer is prevalent, and the mortality rate due to this cancer appears to be correlated with the time span of consumption and the amount consumed. For the present study epithelial hyperplasia and papillomas of the esophagus and forestomach were induced in mice and rats following administration of condensed juice from or extract of pickled vegetables from Linxian County, Henan Province. Only one case of forestomach carcinoma was observed in a rat subsequent to prolonged treatment with pickled extract, indicating that carcinogens in pickled vegetables alone are probably incapable of inducing carcinogenesis.

Evidence for identifying fatty acids in rat liver glutathione S-transferase and its possible involvement in the secondary structure

A rat liver glutathione S-transferase isozyme (GST 3-3) has been purified to apparent electrophoretic homogeneity by procedures including Sephadex G-100, S-hexylglutathione-linked Sepharose, and CM-cellulose column chromatographies. The present study provides evidence for the existence of endogenous fatty acids in the purified GST 3-3 by gas-liquid chromatographic and mass-spectrometric analyses. The liver GST isozyme associated long chain fatty acids such as 14:0, 16:0, 18:0, and 18:1 and the molar ratio of fatty acids to the protein was estimated to be around 3.2. When the enzyme preparation was freed of fatty acids by a mild delipidization technique using Lipidex, the GST activity was significantly decreased. Computer analysis of the circular dichroism spectra revealed that rat liver GST 3-3 contained approximately 49% alpha-helix and 24% random coil. By delipidizing, the enzyme's alpha-helix was decreased to 4% and the random coil was in turn increased to 62%. The enzymatic and structural properties of the delipidized enzyme, however, could be restored to nearly the original levels by recombining with the fatty acids. These findings suggest that weakly bound fatty acids are responsible for the functional capacity of the GST by virtue of changing the protein conformation.

Apical membrane Cl- channels in airway epithelia: anion selectivity and effect of an inhibitor

Previous work has investigated the anion selectivity of transepithelial Cl- secretion by airway epithelia and its inhibition by the Cl(-)-channel blocker 5-nitro-2-(3-phenylpropylamino)benzoate (NPPB). Here we report the anion selectivity of the apical membrane and of the outwardly rectifying Cl- channel and the effect of NPPB on the Cl- channel. The anion selectivity sequence of the apical membrane determined with conventional microelectrodes in the native epithelium was SCN- greater than I- greater than Br- greater than NO3- approximately Cl- much greater than SO(4)2- approximately gluconate-. This contrasts with the observation that Cl- and Br- support transepithelial secretion but that I- does not. Thus the anion selectivity of transepithelial transport is determined by the basolateral membrane Cl- entry step. The anion selectivity of the outwardly rectifying Cl- channel studied in excised patches was the same as that of the apical membrane. We also found that NPPB reversibly blocked the outwardly rectifying Cl- channel from both the internal and external surfaces of the patch. NPPB, 10 microM, completely blocked the channel; lower concentrations caused a decrease in the probability of finding the channel in the open state. NPPB also caused the appearance of a subconductance state of the channel, an occurrence which is rarely observed in the absence of NPPB. These data provide further support for the conclusion that the outwardly rectifying Cl- channel is responsible for Cl- exit from the cell across the apical membrane.

[The significance of retinal nerve fiber layer examination in the diagnosis of glaucoma]

To evaluate the significance of nerve fiber layer (NFL) changes in the diagnosis of glaucoma, the authors examined 197 cases (347 eyes) of normal subjects, primary open angle glaucoma (POAG), low tension glaucoma (LTG) and suspects of these two types of glaucoma. The sensitivity of NFL atrophy to glaucoma was high: in POAG eyes with field loss, 88.9% (64/72) had NFL atrophy. In 123 normal eyes, NFL atrophy was found in only one eye, the specificity of NFL atrophy being 99.2%. All LTG patients and suspects of LTG had NFL atrophy. In the fellow eyes of POAG with normal fields and eyes of POAG suspects, NFL defects occurred in 53.8% (7/13) and 20.6% (15/73) respectively. The examination of NFL is a simple procedure; the nerve fibers themselves are directly observed rather than their function. When half of the thickness of NFL is lost, it Will be manifested clinically. With its high sensitivity and specificity, NFL atrophy can be regarded as an important indicator in the diagnosis of glaucoma.

Absence of diuresis during a 7-day saturation dive at 2.5 ATA N2-O2

Three male divers were studied for 2 days during each of the predive and postdive 1 ATA air control periods and for 7 days at 2.5 ATA (2.3 ATA N2 and 0.2 ATA O2). The chamber temperature was always maintained at a comfort level. Average urine flow remained at 1500 ml.day-1 during both predive and 2.5 ATA periods; urine osmolality also remained constant at around 700 mOSM/kg. On the other hand, daily excretion of Na increased significantly from 139 mEq during the predive period to 178 mEq at 2.5 ATA (P less than 0.05) but returned to the predive level during the postdive period. In contrast, daily K excretion decreased progressively with a significant decrease during the postdive period (P less than 0.05). Plasma osmolality, Na, and K remained unchanged, whereas a 6% reduction of total protein concentration at 2.5 ATA (P less than 0.05) was observed. A quantitatively similar decrease (8%) was observed for hematocrit during the 2.5 ATA period, which did not recover at postdive. These changes were accompanied by a significant increase in urinary excretion of antidiuretic hormone (P less than 0.05) and by decreases in both plasma renin and aldosterone (P less than 0.05) level and urinary excretion of aldosterone (P less than 0.05). Plasma atrial natriuretic factor remained unchanged throughout the entire dive period.

[Analgesic and anti-inflammatory effects and toxicity of houjianxi]

It is effective for acute and chronic laryngopharyngitis clinically. Houjianxi can raise the pain thresholds during hot-plate test in mice, tail flick test in rats, and writhing test in mice with single dose ig 0.125 to 2.0 g/kg. Houjianxi can also inhibit the swelling of hind paw induced by sc 1% carrageenin 0.1 ml in rats as well as the increased vascular permeability induced by ip 0.7% HAC in mice. Toxic side effects were not observed for Houjianxi ig 48 g/kg x 3 within a day in mice and 1.8 g/kg daily for 90 d in rats.

Urinary riboflavin excretion after a load test in rural China as a measure of possible riboflavin deficiency

Urinary excretion of riboflavin was measured in 3318 adults 4 h after an oral dose of riboflavin. Male and female subjects aged 35-64 years were selected from 65 mostly rural counties located in 24 provinces of China. Counties were selected to represent a range of seven of the most prevalent cancer mortality rates in China and within counties households were selected at random. Urinary riboflavin excretion levels after a load test, erythrocyte glutathione reductase activity coefficients (EGR-AC), dietary riboflavin intakes, and a large number of other biochemical, dietary, and environmental parameters were measured. Mean dietary intake of riboflavin was 75 per cent of the Chinese recommended dietary allowances (CRDA). Mean meat intake per reference man was very low (26.4 +/- 23.7 g/d) in comparison to Western standards and milk was not consumed at all in most counties. Mean EGR activity coefficients measured on 'blood pools' for both males (1.47 +/- 0.14) and females (1.48 +/- 0.16) indicated that more than two-thirds of the population surveyed was in the medium or high risk category of riboflavin deficiency. Using current reference standards of less than 1.4 mg for 4-h urinary excretion of riboflavin after a 5 mg load, more than 70 per cent of the individuals examined exhibited low levels usually associated with high risk of riboflavin deficiency. In view of the lack of specificity for clinical indications of riboflavin deficiency and the tentative validity of the present CRDA, the interpretation of the data is problematic. We suggest that the present CRDA for this vitamin is set too high and requires critical review and possibly some revision.

Calcium-dependent regulation of airway epithelial chloride channels

To determine how cell calcium ([Ca2+]c) regulates apical Cl- channels, we measured the rate of 125-Iodide (125I-) efflux to assay Cl- channel activity in intact cells and examined cell-free membrane patches from cultured canine tracheal epithelial cells. The Ca2+ elevating agonist bradykinin and the calcium ionophore A23187 increased 125I- efflux. This response did not require prostaglandin production. Under several conditions, changes in [Ca2+]c were temporally dissociated from changes in channel activation: a transient increase in [Ca2+]c caused a prolonged stimulation of 125I- efflux. Neither Cl- channel activation nor open-channel probability was affected by varying internal [Ca2+] in excised membrane patches. Adenosine 3',5'-cyclic monophosphate (cAMP)- and Ca2(+)-dependent channel activation may be independent: cAMP-stimulated 125I- efflux did not require an increase in [Ca2+]c, Ca2(+)-stimulated efflux did not require an increase in cAMP, and simultaneous addition of A23187 and isoproterenol produced additive effects on 125I- efflux. The data suggest that an increase in [Ca2+]c activates Cl- channels, however, the effect of Ca2+ appears to be indirect, not involving a ligand-type interaction with the channel.