Thermoregulatory responses following injection of 5-hydroxytryptamine into the septohippocampal complex in rats

The present study investigated the change in thermoregulatory responses following microinjection of 5-hydroxytryptamine (5-HT) into the lateral septum and the hippocampus of unanesthetized, unrestrained rats. Intraseptal injection of 5-HT (5 to 20 micrograms) caused a dose-related fall in core temperature (Tb), which was associated with a decrease in heat production (HP). As the decrease in HP can not completely account for the magnitude of the decrease in Tb, increase in heat loss may also be involved in the 5-HT-induced hypothermia. In contrast to observed changes following intraseptal injection, no significant change in either Tb or HP was observed after microinjection of the same doses of 5-HT into the hippocampal areas, indicating that the hypothermic response to intraseptal injection of 5-HT is site specific. Further, the hypothermic response to intraseptal injection of 5-HT was only attenuated by systemic pretreatment with cyproheptadine, but not by naloxone or scopolamine, indicating that the hypothermic response is mediated by 5-HT receptor, but not by endogenous opioid and cholinergic systems.

Effects of 3,6-dimethamidodibenzopyriodonium citrate on slow inward calcium current in isolated guinea pig ventricular cells

The effects of 3,6-dimethamidodibenzopyriodonium citrate (I-65) on action potentials and slow inward calcium current (I(si)) were examined on isolated guinea pig ventricular myocardial cells. I-65 (30-100 mumol.L-1) depressed the action potential duration at 20% repolarization (APD20) and, under voltage-clamp conditions, reduced the amplitude of I(si) without changing the I-V relations. I-65 also showed use-dependent effects on I(si). These suggest that I-65 may block I(si) by acting on the inactivated state of Ca channels.

Human cervical epidermal carcinoma-associated intracellular localization of glycosphingolipid with blood group A type 3 chain

A monoclonal antibody, MRG-1, was produced by immunizing a mouse with a human ovarian mucinous cyst adenocarcinoma-derived cell line, RMUG-L. By immunohistochemical staining, the antigen was found to be exclusively localized in the intracellular structures of the cells used as the antigen and of the epithelial cells in normal human cervical glands. However, although the antigen was predominantly detected in the plasma membrane and the intercellular structure of the middle layer of normal human cervical squamous epithelium (92%), it was also contained in the intracellular structure of cervical epidermal carcinoma at a high frequency (80%). The striking difference in the distribution of the MRG-1 antigen between normal and cancerous tissues was found to be a cervical carcinoma-associated phenomenon and a useful tumor marker for immunohistochemical examination. Since the antigen was found to be of a blood group A-related nature by immunohistochemical staining of the tissues and to be a glycosphingolipid, it was purified from human erythrocytes of blood group A, and the structure was concluded to be GalNAc alpha 1-3Gal(2-1 alpha Fuc)beta 1-3GalNAc alpha 1-3Gal(2-1 alpha Fuc)-beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1' Cer, blood group A type 3 chain-containing glycosphingolipid, by NMR, negative ion FABMS and permethylation analysis. In the subcellular localization analysis of the antigen, type 3-A glycosphingolipid antigen was detected in the Golgi body and the microsomes of RMUG-L cells, and the distribution coincided with the finding by immunohistochemical staining. In addition, in cervical epidermal carcinoma, although the blood group A, mainly type 2-A chain, was localized in the plasma membrane and the intercellular structure, the blood group A type 3 chain was selectively found in the perinuclear structure. Also, the blood group A type 3 chain in cervical dysplasia as well as that in normal cervix was predominant in the plasma membrane. Thus, the selective intracellular localization of blood group A type 3 chain was a phenomenon characteristic of cervical epidermal carcinoma and the carcinoma in situ.

Deficiency of phosphatidylinositol-linked membrane proteins on erythrocytes of different subpopulations in paroxysmal nocturnal hemoglobinuria

The surface phosphatidylinositol (PI)-linked proteins on membrane of paroxysmal nocturnal hemoglobinuria (PNH) erythrocytes (PNHE) was analysed by a flowcytometer (FACS 420). It was found that the loss of acetylcholinesterase (AchE) and decay accelerating factor (DAF), two PI-linked proteins, from cell membrane of PNHE was not synchronous. The hemolysis rates of DAF (-) and AchE (-) PNHE were much higher than that of mixed population in cobra-venom factor (CoF) lysis test. Intact PNHE remaining after CoF lysis had relatively lower immunofluorescent labeling rate of AchE on membrane in comparison with normal erythrocytes. It implied that this subpopulation, in spite of being insensitive to complement lysis, was still abnormal in terms of the amount of PI-linked protein on cell membrane. When these intact PNHE remaining after CoF lysis were incubated with activated polymorphonuclear leukocytes (PMN) for three hours, immunofluorescent labeling of AchE on PNHE was prominently decreased. This indicated that reactive oxidants released from activated PMN might injure PI-linked proteins.

Experimental study of the effect of IH764-3 on pulmonary fibrosis

IH764-3 is a potent component isolated from Salvia miltiorrhiza. We have studied the effect of IH764-3 on experimental pulmonary fibrosis in rats and mice treated with a single intratracheal instillation of bleomycin-A6. Three groups of animals were assigned as BLM+saline, BLM+IH764-3 and normal control. The results indicated that in the treated group, lung coefficient, surfactant, hydroxyproline content and FGF activity were significantly lower than those in the control group (P < 0.05, 0.05, 0.001 and 0.05, respectively). Electron microscopic examination showed that pulmonary ultrastructure was markedly better in the treated group: type II alveolar epithelial cells, infiltrating inflammatory cells, proliferating collagen-forming cells, collagen and elastic fibers were obviously fewer in the treated group. These results demonstrate that IH764-3 has prophylactic and therapeutic effects on pulmonary fibrosis.

[Studies on insecticidal ingredients from culture supernatant of Bacillus thuringiensis]

Studies on the insecticidal activity of culture supernatant of Bacillus thuringiensis var. kurstaki HD-1, by centrifugation, column chromatography, protein sequence determination, bioassay and other methods. Found that insecticidal activity of culture supernatant appeared on synchronism with cells lysis. Main insecticidal ingredients of culture supernatant is toxin protein of 60 kilodaltons (kDa). Analyse hat purified the toxin protein, we find that its amino acid composition was similar with 135-kDa P1 protein, and its sequence of N-terminal 18 amino acid was same with that of part of the P1 protein. The results presented here provided that the toxin protein was the same source with the P1 protein. Further found that supernatant have synergizing action on the sediment of culture.

Widely tunable all-solid-state optical parametric oscillator for the visible and near infrared

An all-solid-state optical parametric oscillator (OPO) has been developed in which the signal and idler waves can be tuned over the ranges 455-665 and 760-1620 nm, respectively, with the potential for covering the entire range 420-2300 nm. The OPO uses a critical type I phase-matching geometry in lithium triborate and is pumped at 355 nm by frequency-tripled radiation from a diode-laser-pumped Nd:YAG laser. Oscillation thresholds (minimum 0.3 mJ), pump depletions (>35%), and linewidths of the OPO are reported.

The modulatory effects of mu and kappa opioid agonists on 5-HT release from hippocampal and hypothalamic slices of euthermic and hibernating ground squirrels

To elucidate the role of opioids in regulating hibernation, the modulatory effects of different opioids on 35 mM K(+)-stimulated [3H]-5-HT release from brain slices were examined in the Richardson's ground squirrels. DAGO ([D-Ala2,N-Me-Phe4,Gly-ol5]-enkephalin), a specific mu agonist, evoked a significant dose-dependent (10(-7)-10(-5) M) inhibition of K(+)-stimulated 5-HT release from hippocampal slices of the non-hibernating squirrels. The inhibitory effect of DAGO was attenuated by either the opioid antagonist naloxone (10(-6) M) or the voltage dependent sodium channel blocker tetrodotoxin (TTX, 10(-6) M). The inhibitory effect of DAGO persisted in the hibernating squirrels; however, a ten fold higher concentration of DAGO (10(-6)-10(-5) M) was required to elicit a significant inhibition. In contrast, kappa agonist U50488 (10(-5) M) exerted a significant enhancement of K(+)-stimulated 5-HT release from hippocampal slices of the non-hibernating squirrels. This enhancement was blocked by either the specific kappa antagonist nor-binaltorphimine (10(-6) M) or TTX (10(-6) M). However, in the hibernating squirrels, the stimulatory effect of U50488 (10(-5) M) on 5-HT release was absent. DAGO and U50488 had no modulatory effects on K(+)-stimulated 5-HT release from the hypothalamic slices of either the non-hibernating or hibernating squirrels. These results demonstrate that the modulatory effects of opioids on 5-HT release are receptor-specific and state-dependent, indicating the complex nature of the roles of different opioids in regulating hibernation.

Germline variable region gene segment derivation of human monoclonal anti-Rh(D) antibodies. Evidence for affinity maturation by somatic hypermutation and repertoire shift

To date, there has been no systematic study of the process of affinity maturation of human antibodies. We therefore sequenced the variable region genes (V genes) of 14 human monoclonal antibodies specific for the erythrocyte Rh(D) alloantigen and determined the germline gene segments of origin and extent of somatic hypermutation. These data were correlated with determinations of antibody affinity. The four IgM antibodies (low affinity) appear to be derived from two germline heavy chain variable region gene segments and one or two germline light chain variable region gene segments and were not extensively mutated. The 10 IgG antibodies (higher affinity) appear to be derived from somatic hypermutation of these V gene segments and by use of new V gene segments or V gene segment combinations (repertoire shift). Affinity generally increased with increasing somatic hypermutation; on average, there were 8.9 point mutations in the V gene segments of the four IgM antibodies (Ka = 1-4 x 10(7)/M-1) compared with 19 point mutations in the V gene segments of the 10 IgG antibodies. The four highest affinity antibodies (Ka = 0.9-3 x 10(9)/M-1) averaged 25.5 point mutations. The use of repertoire shift and somatic hypermutation in affinity maturation of human alloantibodies is similar to data obtained in inbred mice immunized with haptens.

Retention of C60 and C70 fullerenes on reversed-phase high-performance liquid chromatographic stationary phases

The separation of C60 and C70 fullerenes on four different polysiloxane stationary phases was examined. It was determined that polar solvents can be used as mobile phases effectively for the separation of fullerene molecules. Unlike previously published work, a polymeric octadecyl siloxane (ODS) stationary phase provided higher separation factors for C70/C60 than did monomeric ODS stationary phases or phenyl substituted stationary phases. For example, for a methanol-diethyl ether (50:50, v/v) mobile phase and C60, k' approximately 5.0 separation factors, alpha = 3.3, were achieved with polymeric ODS compared to alpha = 2.2, with a monomeric ODS stationary phase. A linear solvation energy relationship (LSER) was used to model the importance of solvent interactions and stationary phase interaction to solute retention.

Generation of intense 10-ps, 193-nm pulses using simple distributed feedback dye lasers and an ArF(*) amplifier

A pair of holographic distributed feedback dye lasers is used to generate 10-ps pulses at two selected wavelengths that are mixed in a BBO crystal to produce a pulse ~ 10 ps in duration at 193 nm. This seed pulse is subsequently amplified in an ArF(*) excimer laser to an energy of 10-15 mJ with <40 microJ in amplified spontaneous emission. The pulses are nearly transform limited and diffraction limited.

The effect of IH764-3 on fibroblast proliferation and function

The effect of IH764-3, a potent component isolated from Salvia miltiorrhiza, on the proliferation and function of cultured fibroblasts was studied. It was found that the fibroblast growth curve had a dose-dependent relationship with IH764-3 concentration. The incorporation of 3H-TdR and 3H-proline into fibroblasts was significantly inhibited by IH764-3, and calmodulin, fibronectin and thrombospondin contents in the test group were obviously lower than those in the control group. Flow cytometry showed that in the IH764-3-treated group, the percentage of cells in G0/G1 phase was higher than that in the control. Electron microscopic observation (TEM and SEM) showed that in the treated group, collagen secretion was decreased. All of these results indicate that IH764-3 exerts a direct inhibitory effect on fibroblast proliferation and affects their ability to synthesize collagen.

All-solid-state optical parametric oscillator for the visible

An all-solid-state optical parametric oscillator (OPO) with signal and idler waves tunable over the ranges 481-457 and 1355-1590 nm, respectively, has been developed. Radiation at 1064 nm from a diode-laser-pumped Nd:AG laser (delivering 10-mJ Q-switched pulses of 18-ns duration at rates of 10-100 Hz) is frequency tripled at efficiencies near 30% and then used to pump the lithium triborate OPO, thus an all-solid-state configuration is realized. Oscillation thresholds (0.4 mJ), pump depletions (50%), external efficiencies (27%), and temperature-tuning rates (signal -0.11 nm/ degrees C, idler +0.87 nm/ degrees C) for the OPO are reported.

State-dependent variation in the inhibitory effect of [D-Ala2, D-Leu5]-enkephalin on hippocampal serotonin release in ground squirrels

Accumulated evidence has suggested that increased endogenous opioid activities may facilitate the onset of hibernation either directly or possibly through modulation of other neurotransmitter systems. The seasonal change of [D-Ala2, D-Leu5]-enkephalin (DADLE), a delta receptor agonist, in modulating K+ (35 mM)-induced [3H]-5-hydroxytryptamine (5-HT) release from the hippocampal and hypothalamic slices of euthermic and hibernating Richardsons' ground squirrels was therefore investigated. DADLE (0.1-10 microM) had no effect on 5-HT release in the hypothalamic slices but elicited a dose-related inhibition on [3H]-5-HT release from the hippocampal slices of the euthermic ground squirrel. The inhibitory effect of DADLE was completely reversed by naloxone (10 microM), but not by tetrodotoxin (1 microM). In contrast, DADLE failed to alter the K(+)-induced 5-HT release from the hippocampal slices of the hibernating ground squirrel. This state-dependent reduction in responsiveness to an opioid is consistent with the hypothesis that enhanced endogenous opioid activity in the hibernating phase could lead to down regulation of the opioid receptors and minimize its inhibition on hippocampal serotonergic activity. A high 5-HT activity would inhibit midbrain reticular activating system indirectly through non-serotonergic fibers, which in turn facilitate the onset or maintenance of hibernation.

New Taxanes from Taxus chinensis

Two new taxane diterpenes, decinnamoyltaxagifine ( 3) and decinnanioyltaxagifine acetate ( 2), have been isolated from the leaves and stems of TAXUS CHINENSIS. Their structures were elucidated by spectroscopic methods. Their (13)C-NMR chemical shifts were assigned.

[Effects of 3,6-dimethamidodibenzopyriodonium citrate (I-65) on action potentials and contractions in guinea pig papillary muscles]

Synchronous recordings of action potentials and contractile force in isolated guinea pig papillary muscles administered 3,6-dimethamidodibenzopyriodonium citrate (I-65) 30 mumol/L showed excitation-contraction uncoupling, ie, the contractile force was markedly depressed although the Vmax and amplitudes of the action potentials were unaffected. At the same concentration, I-65 shortened the duration of the action potentials at 50% and 90% repolarization. However, I-65 at lower concentrations (1-10 mumol/L) decreased Vmax and the amplitude of the slow action potentials which were elicited by isoprenaline in papillary muscles were rendered partially depolarized by KCl 25 mmol/L Tyrode solution. These effects were partially reversed by elevation of the concentration of Ca2+ from 2.7 to 5.4 mmol/L. I-65 also suppressed the abnormal automaticity elicited by BaCl2 and DAD and triggered activity induced by ouabain. The results suggest that I-65 may be a calcium channel blocker.

[Negative inotropic effect of 3,6-dimethamidodibenzopyriodonium citrate (I-65) on guinea pig papillary muscles]

The effects of 3,6-dimethamidodibenzopyriodonium citrate (I-65) on the contractile response of electrically paced guinea pig papillary muscles in vitro were studied. I-65 (0.1-300 mumol/L) decreased the contractile force and inhibited isoprenaline-induced restoration of the contractile response in papillary muscles rendered inexcitable by KCl 22 mmol/L. Both effects were concentration-dependent, and the IC50 were 36.0 and 7.3 mumol/L, respectively. I-65 antagonized the positive inotropic effects of Iso and CaCl2 in a non-competitive manner. Like verapamil, I-65 had a frequency-dependent negative inotropic effect, and delayed the recovery of post-rest potentiation. It is concluded that the negative inotropic effect of I-65 results not only from the reduction of Ca2+-influx through the sarcolemmal membrane, but also from the inhibition of Ca2+ translocation in the sarcoplasmic reticulum.