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To test the hypothesis that heat-shock proteins (HSPs) mediate delayed cardioprotection of prior kappa-opioid receptor (kappa-OR) stimulation, we first correlated cellular injury and viability with the expression of HSP70s in isolated rat ventricular myocytes subjected to prior kappa-OR stimulation with the selective agonist trans-(+/-)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]benzeneacetamide (U-50488H) and delayed lethal simulated ischemia (LSI). Cell injury and viability were indicated by lactate dehydrogenase release and trypan blue exclusion, respectively. The reduced injury and increased viability after pretreatment with U-50488H were concentration dependent and correlated directly with the expression of both stress-inducible (HSP70) and constitutive (HSC70) proteins. The effects mimic those with metabolic inhibition preconditioning (MIP). The cardioprotection against LSI by pretreatment with U-50488H and MIP was abolished and antagonized, respectively, via blockade of the kappa-OR by its selective antagonist, nor-binaltorphimine. We also found that blockade of the production of HSP70 but not HSC70 blocked the inhibitory effect of pretreatment with U-50488H on injury and viability. These observations provide evidence that stress-inducible HSP70 mediates delayed cardioprotection of prior kappa-OR stimulation.

In the mature retina, the dendrites of On and Off ganglion cells are segregated into separate sublaminas of the inner plexiform layer, but early in development these processes are multistratified, ramifying more widely within this synaptic layer. The dendritic pattern exhibited by immature ganglion cells suggests that there may be a functional convergence of On and Off pathways in the developing retina, but previous studies have provided evidence against this. Here we demonstrate by patch-clamp recordings and dye filling that ganglion cells with multistratified dendrites respond to the onset, as well as the offset, of light. We further show that, in the dark-adapted retina, the glutamate analog 2-amino-4-phosphonobutric acid abolishes On and Off discharges in ganglion cells with multistratified dendrites. In contrast, in cells with stratified dendrites, this drug selectively blocks On responses. These findings provide evidence for unique functional attributes of On and Off pathways in the developing retina. The properties of immature ganglion cells documented here have important implications for the roles ascribed to neuronal activity in refining connections during the early development of the visual system.

The primary purpose of the present study was to compare the cardioprotective effects of the extract from radix stephaniae tetrandrae (RST) and its individual compounds, tetrandrine (Tet) and fanchinoline (Fan). Secondly, we also compared the cardiac effects of the individual compounds and the RST extract with those of verapamil, a classical Ca2+ channel blocker. The Langendorff isolated perfused rat heart preparation was used. Regional ischaemia and reperfusion was employed to induce myocardial infarct and arrhythmia. Infarct, arrhythmia, heart rate and coronary artery flow were determined in hearts treated with vehicle, RST extract, Tet, Fan, or verapamil. It was found that RST extract, of which only 9% was Tet, and Tet alone produced equally potent ameliorating effects on arrhythmia and infarct induced by ischaemia and reperfusion without further inhibiting ischaemia-reduced heart rate and coronary artery flow. Fan had no effects on arrhythmia and infarct induced by ischaemia and reperfusion; but it induced S-T segment elevation and further reduced heart rate and coronary artery flow during ischaemia. Verapamil also ameliorated the effects of ischaemia and reperfusion on arrhythmia and infarct. It should be noted that 1 microM verapamil, that produced comparable effects on infarct and arrhythmia to the RST extract and Tet, further inhibited heart rate during ischaemia. The results indicate that the RST extract produces equally potent cardioprotective and anti-arrhythmic effects as Tet alone. Both RST extract and Tet may be better choices for the treatment of arrhythmia and infarct induced by myocardial ischaemia and reperfusion than the classical Ca2+ channel blocker, verapamil as they do not further reduce heart rate during ischaemia.

Two series of experiments were performed in the isolated perfused rat heart to determine the role of kappa- and delta-opioid receptors (OR) in cardioprotection of ischemic preconditioning (IP). In the first series of experiments, it was found that IP with two cycles of 5-min regional ischemia followed by 5-min reperfusion each reduced infarct size induced by 30-min ischemia, and the ameliorating effect of IP on infarct was attenuated with blockade of either 5 x 10(-6) mol/l nor-binaltorphimine (nor-BNI), a selective kappa-OR antagonist, or 5 x 10(-6) mol/l naltrindole (NTD), a selective delta-OR antagonist. The second series showed that U50,488H, a selective kappa-OR agonist, or D-Ala(2)-D-leu(5)-enkephalin (DADLE), a selective delta-OR agonist, dose dependently reduced the infarct size induced by ischemia, which mimicked the effects of IP. The effect of 10(-5) mol/l U50,488H on infarct was significantly attenuated by blockade of protein kinase C (PKC) with specific PKC inhibitors, 5 x 10(-6) mol/l chelerythrine or 8 x 10(-7) mol/l calphostin C, as well as by blockade of ATP-sensitive K(+) (K(ATP)) channels with blockers of the channel, 10(-5) mol/l glibenclamide or 10(-4) mol/l 5-hydroxydecanoate. IP also reduced arrhythmia induced by ischemia. Nor-BNI, but not NTD, attenuated, while U50,488H, but not DADLE, mimicked the antiarrhythmic action of IP. In conclusion, the present study has provided first evidence that kappa-OR mediates the ameliorating effects of IP on infarct and arrhythmia induced by ischemia, whereas delta-OR mediates the effects only on infarct. Both PKC and K(ATP) channels mediate the effect of activation of kappa-OR on infarct.

Bacterial strains grown in the presence of low concentrations of dimethyl sulfoxide (DMSO) exhibit significant qualitative and quantitative alterations in the production of secondary metabolites. This effect was confirmed for a variety of biosynthetic families, including chloramphenicol (chorismate), thiostrepton (peptide) and tetracenomycin (polyketide), and for natural and recombinant strains of streptomycetes; a similar effect was seen with antibiotic-producing bacilli such as B. circulans. Increase in antibiotic production was not the result of a change in the growth rate of these organisms, since yields of biomass were similar in media with and without DMSO (up to 3%). We suggest that the addition of compounds such as DMSO provides a means of examining the full biosynthetic potential of microbes and might be used to promote secondary metabolite production. The mode of action of DMSO is not known, but in the cases studied it may act at the level of translation.

Trifluoromethyl ketones (TFK) are potent inhibitors of a variety of serine hydrolases. The TFK inhibitor, 3-(4-mercaptobutylthio)-1,1,1-trifluoro-2-propanone (MBTFP), was found to competitively inhibit cutinase activity (I50 = 9.4 x 10(-3)) from the fungal plant pathogen Monilinia fructicola and to serve as an effective affinity ligand for the purification of cutinases from culture filtrates. The TFK inhibitors, 3-n-octylthio-1,1,1-trifluoro-2-propanone (OTFP) and 3-n-pentylthio-1,1,1-trifluoro-2-propanone (PTFP), also inhibited cutinase activity with I50 values of 1.6 x 10(-6) and 2.3 x 10(-4) M, respectively. Buffer containing OTFP was the strongest eluant for cutinases of M. fructicola and provided the best purification factor and yield, although buffers containing OTFP, detergent, and salt were found to be effective for eluting cutinases bound to MBTFP-Sepharose. Buffer containing 0.5% Triton X-100 also selectively eluted cutinases from the affinity column. Two-dimensional electrophoretic analysis by SDS-PAGE and isoelectric focusing of the affinity-purified cutinase fraction indicated activity associated with proteins of pI 8.2 and molecular masses of approximately 18.6 and 20.8 kDa. These proteins hydrolyzed [3H]cutin and artificial substrates such as p-nitrophenylbutyrate and related esters, typical of other cutinases, but differ from previously characterized cutinases in molecular mass. The two low-molecular-weight proteins resolved by 2-D gel electrophoresis were subjected to in-gel digestion with Lys-C and the resulting peptide fragments were separated by Microbore-HPLC. The amino acid sequences of several internal peptide fragments had high homology with cutinase sequences from other fungi, particularly the plant pathogen Botrytis cinerea. Our study illustrates the potential of TFK ligands for the affinity purification of cutinases and indicates that the cutinases from M. fructicola have novel features warranting further study.

As a route to accessing the potential chemical diversity of uncultivable microbes from the soil, combinatorial biosynthetic libraries were constructed by cloning large fragments of DNA isolated from soil into a Streptomyces lividans host. Four novel compounds, terragines A (1), B (2), C (3), and D (4), were isolated from recombinant 436-s4-5b1, and another novel compound, terragine E (5), was isolated from 446-s3-102g1. The structures were determined by a combination of spectroscopic techniques, primarily 2D NMR.

Human serum containing sperm-agglutinating antibodies was used to screen a testis cDNA expression library to identify the cognate antigens that may be responsible for this biological effect. The longest positive phage clone (1.9 kb) was sequenced and found to be a testis-specific isoform of calpastatin (tCAST). The testis-specific segment of tCAST is encoded by a single exon within intron 14 of the calpastatin gene. A unique protein isoform is produced that differs in domain structure from the somatic calpastatins (sCAST). Human sCAST most commonly has an N-terminal domain L plus the four functional calpain inhibitory domains. Human tCAST consists of a 40-amino-acid N-terminal T domain plus a part of domain II and all of domains III and IV from the somatic isoform. Our data show that the T domain can target cytosolic localization and membrane association of tCAST, whereas domain I of sCAST exhibits a nuclear localization function. Calpastatin is the endogenous inhibitor of calpain. The calpain/calpastatin system is involved in membrane fusion events for several cell types, and calpain has been localized to the sperm acrosome. We detected tCAST in human sperm and testes extracts by Western blotting with specific antisera. These observations suggest that tCAST may modulate calpain in the calcium-mediated acrosome reaction that is required for fertilization.

The spontaneous discharge patterns of developing retinal ganglion cells are thought to play a crucial role in the refinement of early retinofugal projections. To investigate the contributions of intrinsic membrane properties to the spontaneous activity of developing ganglion cells, we assessed the effects of blocking large and small calcium-activated potassium conductances on the temporal pattern of such discharges by means of patch-clamp recordings from the intact retina of developing ferrets. Application of apamin and charybdotoxin (CTX), which selectively block the small and large calcium-activated potassium channels, respectively, resulted in significant changes in spontaneous firings. In cells recorded from the oldest animals [postnatal day 30 (P30)-P45], which manifested relatively sustained discharge patterns, application of either blocker induced bursting activity. With CTX the bursts were highly periodic, short in duration, and of high frequency. In contrast, with apamin the interburst intervals were longer, less regular, and lower in overall spike frequency. These differences between the effects of the two blockers on spontaneous activity were documented by spectral analysis of discharge patterns. Filling cells from which recordings were made with Lucifer yellow revealed that these effects were obtained in all three morphological classes of cells: alpha, beta, and gamma. These findings provide the first evidence that apamin- and CTX-sensitive K+ conductances can have differential effects on the spontaneous discharge patterns of retinal ganglion cells. Remarkably, the bursts of activity obtained after apamin application in more mature neurons appeared very similar to the spontaneous bursting patterns observed in developing neurons. These findings suggest that the maturation of calcium-activated potassium channels, particularly the apamin-sensitive conductance, may contribute to the changes in spontaneous firings exhibited by retinal ganglion cells during the course of normal development.

The hypocotyls and cotyledons of the asepetic seedling of Brassica campestris ssp. chinensis L cv. Pudongaijiecai) were used as explants for tissue culture. Adventitious buds were differentiated on modified MS medium supplemented with TDZ 1-2 mg/L, NAA 0.2-1 mg/L and AgNO3 7.5 mg/L. The percentage of explants which formed buds of cotyledons was about 56%, and that of hypocotyls was about 37%. When the regenerated explants were transferred onto MS medium with 2 i.p. 5 mg/L and NAA 0.1 mg/L for two weeks, whole plantlets were obtained by culturing the regenerated shoots on 1/2 MS medium with NAA 0.1 mg/L. Agrobacterium tumefaciens strain (LBA 4404/PBI 121) carrying the GUS gene and Npt II gene was used for transformation. After 2 days of coculture, the hypocotyls and cotyledons were transferred onto regenerated medium containing CP 300 mg/L for bud formation. After 4-5 weeks, the differentiated buds were transferred onto selection medium with CP 200 mg/L and Km 10 mg/L for 1 month, then the green shoots were transferred onto the rooting medium containing Cef 100 mg/L and Km 20 mg/L. 4-5 weeks later, plantlets with Km resistance were obtained and some of them showed higher enzymatic activities of beta-glucuronidase than control ones.

In order to ensure that the intake of iodine from iodized salt is adequate, the effects of cooking, storage and iodination on iodine content in iodized salt have been studied. For monitoring the analytical performance, a quality control examination was also undertaken. The loss of iodine was greater when salt was stored in plastic bag than in glass bottle. The loss was greater in fortified salt stored at 37 degrees C and under 76% humidity than in that at 20-25 degrees C and under lower humidity. The retention of iodine varied with the kind of foods and also was influenced by the water content of cooked food. In general, the retention of iodine during cooking varied considerably (from 36.6% to 86.1%). The iodine concentration in salts varied greater from 3.0 to 100.3 mg/kg in salt for markets, and from 0 to 90.0 mg/kg in salts for households. 48.3% of samples from markets were found to be in compliance with national standards (30-50 mg/kg), and 72.0% of samples from households were in compliance with national standard (20-50 mg/kg). Analytical data collected from 8 of the cooperative laboratories for an analytical reference material showed a 95% confidence interval of the population mean for both precision and accuracy, falling within X +/- 2SD and passing quality control examination.

During development of CGP56901, a monoclonal antibody (MAb) specific for a unique epitope on human IgE, the protein A-purified IgG from one of the candidate production cell lines, showed an additional minor heavy chain (H-chain) band with a molecular weight slightly lower than that of the principal H-chain band on SDS-PAGE. The N-terminal amino acid sequence of this minor H-chain species indicated that at least the first 30 amino acids were identical to those of the antibody light-chain (L-chain) variable domain. More detailed studies using peptide mapping and amino acid sequencing analysis confirmed a crossover event between the V genes of the antibody. The position is between Arg108 of the L chain and Ala124 of the H chain. This crossover resulted in a variant H chain, which had 16 fewer amino acid residues than the normal CGP56901 H chain. These results show that peptide mapping is a useful "first-line" analytical tool in the characterization of the quality of the monoclonal antibody.

The segregation, integration and stability of the transgene-Bt (Bacillus thuringensis) in eight transformants created by three ways of transformation were studied by means of PCR (Polymerase chain reaction) and DNA molecular hybridization. The results are as follows: (1) The transgene-Bt in most of the progenies of the transformants showed simple Mendelian segregation. Although some deviation from Mendelian fashion existed in the early generations, the normal Mendelian segregation would be found after R3 generations and the transgene could fix in the populations. (2) The integration patterns of the transgene varied to the some extent in the different transformants, but they were characterized by either smaller band and copy numbers or cascade integration or closely linked integration in all transformants. (3) Changes of the Southern land pattern were found in some families of some transformants, especially, in the two families of Ding 4R5.

It is now well established that retinal ganglion activity is essential to the normal development of the mammalian visual system. Moreover, it has been shown that the critical periods of activity occur well before the time when the retina is capable of detecting light. To better understand these activity-mediated events, patch-clamp studies have begun to examine the development of intrinsic membrane properties in isolated and intact retinal ganglion cells. Here we review the major findings of these studies and highlight the similarities in the functional development of ganglion cells in a number of mammalian species., (Copyright 1998 Academic Press.)

Patch-clamp recordings were made from isolated and intact retinal ganglion cells (RGCs) of the ferret to examine the calcium-activated potassium channels expressed by these neurons and to determine their functional role in the generation of spikes and spiking patterns. Single-channel recordings from isolated neurons revealed the presence of two calcium-sensitive potassium channels that had conductances of 118 and 22 pS. The properties of these two channels were shown to be similar to those ascribed to the large-conductance calcium-activated potassium channel (BKCa) and small-conductance calcium-activated potassium channel (SKCa) channels in other neurons. Whole cell recordings from isolated RGCs showed that apamin and charybdotoxin (CTX), specific blockers of the SKCa and BKCa channels, respectively, resulted in a shortening of the time to threshold and a reduction in the hyperpolarization after the spike. Addition of these blockers also resulted in a significant increase in spike frequency over a wide range of maintained depolarizations. Similar effects of apamin and CTX were observed during current-clamp recordings from intact alpha and beta ganglion cells, morphologically identified after Lucifer yellow filling. About 20% of these neurons did not exhibit a sensitivity to either blocker, suggesting the presence of functionally distinct subgroups of alpha and beta RGCs on the basis of their intrinsic membrane properties. The expression of these calcium-activated potassium channels in the majority of alpha and beta cells provides a means by which the activity of these output neurons could be modulated by retinal neurochemicals.

Senosory neurons manifest pronounced changes in excitability during maturation, but the factors contributing to this ubiquitous developmental phenomenon are not well understood. To assess the contribution of intrinsic membrane properties to such changes in excitability, in the present study whole cell patch-clamp recordings were made from developing ganglion cells in the intact retina of postnatal rats. During a relatively brief developmental period (postnatal days P7-P27) ganglion cells exhibited pronounced changes in the discharge patterns generated by depolarizing current injections. The youngest cells (P7-P17) typically responded to maintained depolarizations with only a single spike or a rapidly adapting discharge pattern. In contrast, the predominant response mode of more mature cells (P21-P27) was a series of repetitive discharges that lasted for the duration of the depolarization period, and by P25 all cells responded in this manner. These functional changes characterized all three morphologically defined cell classes identified by intracellular labeling with Lucifer yellow. To determine if expression of the potassium current (Ia) and the kinetics of the Na-channel related to the increased excitability of developing ganglion cells described above, current- and voltage-clamp recordings were made from individual neurons. The different firing patterns manifested by developing retinal ganglion cells did not reflect the presence or absence of the Ia conductance, although cells expressing Ia tended to generate spikes of shorter duration. With maturation the speed of recovery from inactivation of the Na current increased markedly and this related to the increased excitability of developing ganglion cells. Neurons yielding only a single spike to maintained depolarization were characterized by the slowest speed of recovery; cells with rapidly adapting discharges showed a faster recovery and those capable of repetitive firing recovered fastest from Na-channel inactivation. It is suggested that these changes in intrinsic membrane properties may relate to the different functional roles subserved by ganglion cells during development.

Aim: To study the effect of 10-hydroxy-2-decenoic acid (HDA) on the macrophages activity of rats in vitro., Methods: To measure the effects of HDA on phagocytosis, the production of antitumor cytokines tumor necrosis factor (TNF) and interleukin-1 (IL-1) in vitro., Results: HDA 50, 100 mg.L-1 promoted phagocytic activity from 0.353 +/- 0.017 to 0.39 +/- 0.04 and 0.382 +/- 0.017 A, increased TNF and IL-1 production from 0.23 +/- 0.07% to 0.43 +/- 0.04%, 0.47 +/- 0.04% and from 2384 +/- 180 to 2943 +/- 295, 3825 +/- 450 dpm, respectively., Conclusion: The upregulating effects of HDA on phagocytosis of PMO and production of TNF, IL-1 contribute to the host antitumor and immunomodulating mechanism.

Ingenol 3,5,20-triacetate (ITA), one of the ingenol derivatives, is a selective inhibitor of human immunodeficiency virus (HIV) replication in vitro. ITA inhibited the replication of HIV strains in MT-4 cells at concentrations of 0.051 to 0.65 microM. This concentration was approximately 10(3)-fold lower than its cytotoxic threshold. The mechanism of action of ITA is primarily attributed to the inhibition of viral adsorption to the host cells, but it is distinct from the mechanism of inhibition by other adsorption inhibitors.

Planar LiNbO(3) waveguides with a 5-mm tapered region and a 10-mm homogeneous slab waveguide region were fabricated by a double proton-exchange process. The 4-microm waveguide entrance gives rise to a coupling efficiency as high as 93%; the precise control of the depth profile of the tapered region results in a low 1-dB power transfer loss from the tapered region to the 0.4-microm-depth working region. The techniques developed provide an alternative to prism coupling into planar waveguides in Cerenkov second-harmonic generation applications.

We tried to demonstrate the electron microscopic histochemical localization of membrane Ca(2+)-ATPase activity in glutaraldehyde-fixed rat sciatic nerves. Although conventional glutaraldehyde fixatives containing impurities interfered with the reactivity of Ca(2+)-ATPase, this activity was successfully preserved in the tissues fixed with pure glutaraldehyde as well as in those fixed with paraformaldehyde. In unmyelinated nerve fibers, an ATPase activity depending on 10 mM CaCl2 was detected on the whole external surface of Schwann cell plasma membranes. In myelinated fibers, this activity was localized on the surface of Schwann cell outer loops at the paranodal region of Ranvier nodes and on the axonal membrane at the nodal region. Another activity depending on 0.1 mM CaCl2 was demonstrated on the axolemma of unmyelinated fibers. These results indicated that there may be two types of Ca(2+)-ATPase activities showing high and low affinity to calcium ions localized in peripheral nerve systems in a different manner between myelinated and unmyelinated fibers.

Ultrashort optical second-harmonic pulses based on a traditional phase-matched Cerenkov second-harmonic generation scheme, with an additional prism to equalize the arrival time, are proposed. Proton-exchanged KTP, LiNbO(3) waveguides, and several prism materials are considered in the evaluation. There is no constraint on crystal length, making high efficiency possible as well as preserving an ultrashort pulse width. The proposed approach may be a practical and efficient way to achieve convenient ultrashort harmonic pulses.

On Zorbax Sil column with a mobile phase of chloroform-isooctane-methyl alcohol-acetic acid (30: 13: 4: 3), the content of syrigin in Zengzhi granules was determined by HPLC at 270nm. The results show that the recovery is 102.52 +/- 1.98% and RSD 1.93%. The content of syrigin is 0.0543 +/- 0.0005mg/g.

This article reported the image analysis of normal epithelia of bronchi (group 1), hyperplasia epithelia (group 2), atypical hyperplasia epithelia (group 3) and adenocarcinoma (group 4) of the lung in the hamsters induced by tin mine dust and chimney dust in Yunnan Tin Min CO. 16 parameters were observed and compared. Each value was tested by stepwise discriminational classification and an accuracy rate of 95% was reached. DNA ploidy was investigated, and no case of > 5C cell was found in normal and hyperplasia group. Severe atypia had a lower percentage, (4.00%) and lung adenocarcinoma was characterized by a high percentage of > 5C cell (10.75%), A significant difference was shown between the percentage of > 5C cell of severe atypia and that of adenocarcinoma. Significantly different (P < 0.01).

Simultaneous phase- and group-velocity-matched generation of ultrashort optical second-harmonic pulses based on a quasi-phase-matched Cerenkov second-harmonic generation scheme is proposed. We compare our scheme with other schemes with respect to its ability to achieve high conversion efficiency, its enhancement with respect to cw second-harmonic generation, and its sensitivity to waveguide-period fluctuation; ion-exchanged KTP and LiNbO(3) waveguides are considered in the evaluation. We believe our proposed scheme is easy to implement, and there is no constraint on crystal length in achieving high efficiency as well as in preserving an ultrashort pulse width. 100% efficiency is potentially obtainable from sufficiently long crystals.

The venous architecture in donor flaps was observed in 17 fresh cadavers by injection of latex or ink into the vessels or by making corrosion-cast specimens. The pattern of the veins resembles that of the arteries, with the difference that there is another set of venous trunks which do not accompany the arteries. Because these trunks are of larger caliber, they are the main drainage route for flaps. There are three types of drainage based on the anatomical architecture: 1) the superficial trunk is the main drainage path; 2) the deep trunk is the main path; 3) both superficial and deep veins are involved. These morphological considerations are the basis for selection of veins for anastomosis in microsurgery. The axial veins in temporal, frontal and facial flaps on the dorsum of the hand and the foot usually loosely accompany the axial arteries. The characteristics of these vascular pedicules should be studied in transplant operation.

To evaluate the relationship between aluminum and renal osteodystrophy, iliac bone biopsies and bone aluminum staining were studied in 51 patients with end-stage renal failure. In 27 of 51 cases were measured PTH, 1.25 (OH)2D3 levels and bone aluminum contents. We found that the incidence of renal osteodystrophy was 100%. The positive rate of bone aluminum staining was 12%. The rate was highest in low-turnover osteomalacia. Serum aluminum and bone aluminum contents were significantly higher than controls in three types of renal osteodystrophy on hemodialysis. Bone aluminum correlated with the duration of hemodialysis (r = 0.704), also with the serum calcium (r = 0.341). The duration of hemodialysis and bone aluminum contents were markedly longer and higher in positive group of bone aluminum staining than that of negative group (P < 0.001, respectively). Our data suggested that: (1) aluminum accumulation in bone was related to duration of hemodialysis, (2) aluminum may play important roles in the intervention of bone mineralization.

Twenty-eight patients with primary aldosteronism were treated from 1974 to 1990. The serum potassium concentration was higher than normal level in all patients with the exception of one whose serum potassium concentration was normal. All of 14 tested patients had low renin values. The plasma aldosterone concentration was higher than standard value in all of 5 patients, and the A/PRA ratio was more than 400. Spironolactone administered preoperatively could not only normalize serum potassium concentration level and blood pressure, but also predict postoperative prognosis of hypertension. Only 37.5% of adenomas were detected by retroperitoneal pneumography with tomography in the early period. 80.0% of adenomas were found by B-ultrasonography, and 92.8% by CT after 1982. The operation was done through abdominal incision because of indefinite localization of adenoma before 1982, and the operation was performed through lumbar incision because of definite localization of adenoma after 1982.

Wistar rats (close cloned strain) were used to investigate the effect of endogenous laminin and fibronectin on axons, Schwann cells and perineurial cells in the regenerating peripheral nervous system (PNS). Sciatic nerve grafts obtained from donor rats were frozen, thawed and treated with rabbit anti-rat laminin or anti-fibronectin antiserum. Control grafts were treated with normal rabbit serum alone. One cm long portions of the sciatic nerve of the recipient rats were replaced with grafts. At 15 days after transplantation the number of regenerated axons in the laminin- and fibronectin-depleted grafts was half of that in the control. The growing axons in the laminin-depleted grafts did not recognize the basal lamina scaffolds (BLS) remaining in the basal lamina tubes, while in the control and fibronectin-depleted grafts 90% or more of axons grew inside the BLS. Elongation of axons always preceded migration of Schwann cells with the latter subsequently adhering to and wrapping around the former. Perineurium-forming fibroblastic cells recognized the combination of axons and Schwann cells and formed perineurial fasciculi around them. These fibroblastic cells did not recognize empty BLS but responded to them only when fibronectin was depleted. Macrophages sometimes closely faced the naked axons which elongated outside the BLS. These results suggest that in the early stages of nerve regeneration endogenous laminin and fibronectin not only regulate the growth of regenerating nerve fibers, but also exert a positive influence on perineurial cells and macrophages, both of which play important roles in nerve tissue injury and repair.

Although the intracellular toxic sites of paraquat, a herbicide toxic to human bodies, have remained unclear for a long time, we recently demonstrated paraquat-induced mitochondrial injury in rat lung and liver in vivo. In the present study, cultured human lung cells (A549 adenocarcinoma cell line) which received 0.15 mM paraquat (equivalent to 40 mg/kg i.v.) showed selective mitochondrial breakage at 6-24 hr and died at 36-48 hr. These results suggest that mitochondria are the initial toxic site of paraquat in vitro as well as in vivo in contrast to the previously proposed microsome theory.

Regeneration of the sciatic nerve in transplanted nerve grafts in which laminin was inactivated was examined electron microscopically. Nerve grafts for transplantation were obtained from close cloned donor Wistar rats; 1-cm nerve segments of the sciatic nerve were frozen and thawed to kill the Schwann cells. Control recipient rats received grafts treated with normal rabbit serum to repair the artificially-made complete defect of the right sciatic nerve, and the experimental group of rats received grafts doubly treated with normal serum and rabbit anti-laminin antiserum. In the control grafts regenerating axons grew almost completely through the inside of the basal lamina scaffolds (92%) and adhered to the structure, while in the anti-laminin antiserum treated grafts the axons were present outside (52%) and inside (48%) the scaffolds simultaneously. In this case, the adhesion of axons to the scaffolds was obscure. Axons were associated with and without Schwann cells both inside and outside the basal lamina scaffolds. No unassociated Schwann cells were observed. The maximal number of axons in a 2 mm portion of the antiserum-treated grafts was approximately 250 axons per 100 x 100 microns square and 520 in the control at 15 days. At 30 days, almost the same number of axons was found at the distal (8 mm) portion of both groups. The growth in the former was delayed for 3 days. These results indicate that regenerating peripheral nerve axons may enter the basal lamina scaffolds and grow well because of the neurotrophic function of laminin present at the inner side of Schwann cell basal lamina.

Pure rat liver heavy mitochondrial fractions, in which the absence of significant microsomal contamination was confirmed by electron microscopy and by the lack of glucose-6-phosphatase activity, were used to demonstrate the effect of paraquat on mitochondrial ultrastructure in the presence of external NADH. Starved mitochondria (orthodox conformation) did not show O2 uptake or structural injury from either paraquat alone or NADH alone. Marked O2 uptake and structural breakage occurred only when paraquat and NADH were added in combination. These alterations were resistant to rotenone and malate plus glutamate or NADPH could not substitute for NADH. Paraquat was reduced anaerobically by the mitochondria in the presence of NADH, but not of NADPH. The addition of superoxide dismutase, ferricytochrome c or p-benzoquinone protected against the breakage of mitochondria caused by paraquat plus NADH. These results demonstrate that mitochondria may produce paraquat radicals in the presence of extramitochondrial NADH and thus generate superoxide anion radicals, resulting in structural injury to the mitochondria, by mechanisms that may involve the mitochondrial outer membrane rather than the electron transfer chain. These mitochondrial mechanisms in paraquat toxicity seemed to be more probable in vivo than are microsomal mechanisms; the latter are postulated to function in detoxication because phenobarbital diminished paraquat toxicity and SKF 525-A or cobaltous ions enhanced the toxicity.

An introduction of the method of the theory of quantification II is given, and it is applied to evaluation of the factors influencing the use of IUD. From the epidemiological data obtained in Jilin City, eight more important factors were screened. These factors are age of first parturition, age of first menses, condition of putting the IUD in, number of early stage induced abortion, number of gestation, labour posture, labour intensity and number of parturition. By comparing the results of analysis between the theory of the quantification and the Bayes discrimination analysis, it is shown that the former method is more objective and therefore the results are more reliable.

With the advent of sonography and CT, renal cell carcinoma has increasingly been diagnosed in its early stage, with simple hematuria or no symptoms as the incidence of patients with masses and extrarenal extensions decreased. Correlating the clinical manifestations with stage, hematuria and pain may not imply an advanced lesion (31.4% Stage I). By adequate use of B ultrasonography and/or other instrument, many of renal cell carcinoma could be detected in its asymptomatic stage, a crucial requirement for better therapeutic results. The authors' data showed that fever, elevated ESR, varicocele and general malaise did imply advanced lesions or possible early metastasis after operation. On the other hand, complication with hypertension or erythremia could speak for an early lesion if diagnosis is made in time. Therefore, stratification of the extrarenal manifestations into endocrine and non-endocrine phases may help assess prognosis.

The production of free radicals, superoxide anions (O2-), and hydrogen peroxide (H2O2) was histochemically investigated in human neutrophils that were stimulated by either phagocytosis or the calcium ionophore A23187. To demonstrate O2-, peripheral neutrophils from healthy donors were incubated at 37 degrees C in a medium containing nitroblue tetrazolium and glucose in the presence of either opsonized zymosan A and/or A23187. To demonstrate H2O2, neutrophils pretreated with a stimulant for 10 min were washed and incubated in a cerium medium containing CeCl3 and glucose in a Tris-maleate buffer. In cells engaged in phagocytosis, diformazan (for O2-) and cerium perhydroxide deposits (for H2O2) were restricted to the neutrophil-particle interface and on the inner surface of phagosomes. The remaining free surface of the plasma membrane was devoid of reaction products. In the case of neutrophils stimulated with A23187, the production of O2- and H2O2 was visualized over the whole surface of the plasma membrane. These histochemical reactions were inhibited by p-benzoquinone, superoxide dismutase, ferricytochrome c or catalase, and p-diazobenzenesulfonate (a membrane-impermeable protein denaturant). The results showed that human neutrophils produce free radicals exocellularly and that the site of production varies with different stimuli.

The role of iron deficiency in noise-induced hearing loss (NIHL) was evaluated in 64 rats of four different experimental groups. Iron-deficient rats (ID-rats) and normal rats (N-rats) were simultaneously exposed to a steady state white noise (20-10,000 Hz) at 110 dB SPL for 30 min. Unexposed ID- and N-rats served as controls. In N-rats the temporary threshold shifts (TTS) would have completely disappeared if the animals were allowed to survive for 72 h. No permanent threshold shift (PTS) was seen in any of the N-rats. The ultrastructural correlates in N-rats are stereocilia disarray and mitochondria swelling in outer hair cells (OHCs). The TTS in ID-rats were larger than those in the N-rats, and most ID-rats with larger threshold shifts showed varying degrees of PTSs at 11 days post-exposure. The ultrastructural correlates of NIHL in ID-rats are obvious pathology of the stereocilia, such as segmental coalescence of stereocilia of many continuous OHCs and fusion of the tips of stereocilia of OHCs, and a significant reduction of mitochondria as well as slight degeneration of nucleus in the OHCs. It is concluded that iron deficiency can provide a pathological basis for NIHL.

Unlabelled: STUDY OBJECTIVE0--he aim was to explore the cellular mechanisms responsible for the depressant effects of adenosine in human atrial tissues., Design: Conventional microelectrode technique was used to record transmembrane action potential of human atrial tissues obtained at cardiac surgery. Effects of adenosine (0.1-100 microM) on action potential characteristics and contractile force of human atrial fibres in the absence and presence of an adenosine receptor antagonist (DPSPX) were evaluated. Results were then compared with those obtained from the canine atrial tissues., Experimental Material: Atrial tissues obtained from hearts of 25 patients undergoing corrective cardiac surgery were used. Seven mongrel dogs were anaesthetised and strands of atrial muscle were removed and used for comparison., Measurements and Main Results: In human atrial fibres showing fast response action potential (mean dV/dtmax around 100 V.s-1) in normal [K]o (4 mM) Tyrode solution, adenosine (1 nM-10 microM) did not induce consistent effects on the action potential characteristics. When the fibres were depolarised in high [K]o (27 mM) or in atrial fibres showing slow response action potential (dV/dtmax less than 50 V.s-1), however, 10 microM adenosine reduced the upstroke velocity and the amplitude of action potential significantly and markedly depressed the contractile force. In atrial fibres spontaneously active in normal Tyrode solution (maximum diastolic potential around -50 mV), adenosine inhibited rate of spontaneous discharge in a concentration dependent manner. Delayed afterdepolarisation and aftercontraction induced by adrenaline or/and high [Ca]o were also suppressed. The depressant effects of adenosine were blocked after pretreatment with 50 microM DPSPX, a specific antagonist for adenosine receptor., Conclusions: These findings show that adenosine may abolish abnormal automatic rhythms and triggered activity in human atria.

Chlorhexidine has been utilized as a root canal irrigant since 1971. It is a broad-spectrum antimicrobial agent with minimal toxicity and residual long-term antibacterial capability. Although a sodium hypochlorite solution has been shown to have a better antimicrobial effect than chlorhexidine, its corrosive effect has prevented its further use especially since the in vitro antimicrobial effect of chlorhexidine has been shown to not be much less. However, the efficacy of chlorhexidine as an endodontic irrigant and intracanal medicament, requires further research in vivo. Therefore, in this study, the clinical effects of chlorhexidine were evaluated by comparing its antimicrobial properties with other endodontic irrigants. One hundred and fifty teeth were selected and evenly divided into 6 groups according to their pathological status. The root cancals were prepared with conventional hand filing or ultrasonic filing, respectively, and were rinsed singly with either chlorhexidine, EDTA or distilled water. The contents of each root canal before or after debridement were cultured in an incubator. The results showed that chlorhexidine with hand filing in one week and with endosonics in 48 hours had a better antimicrobial effect than did EDTA. As compared with the control group (distilled water), chlorhexidine showed marked antimicrobial effect in both hand and endosonic filing. It is concluded that chlorhexidine has an antibacterial effect as an endodontic irrigant in clinical applications.

The cytochrome oxidase activity of rat dorsal root ganglion cells was cytochemically and quantitatively measured. The 100 microns thick tissue slices fixed for 10 min were incubated in a DAB medium for 0, 30, 60, and 90 min at 37 degrees C, and electron-dense deposit areas within the mitochondrial intermembrane-intracristal spaces were measured with a computer-controlled image analyzer. The activity was expressed as deposit accumulation rate filling the mitochondrial space, (1 unit corresponds to the deposit filling 100% of the mitochondrial space per hour). Three different activities of the enzyme in either large pale cells or small dark cells of sensory neurons could be distinguished, based on the quantitative analysis, as large cells with intense (0.83 units), intermediate (0.38), and weak activity (0.22), and small cells with the same degrees of activity (1.04, 0.35, and 0.11, respectively). The results indicate that accumulation rate measurements of reaction product may be useful to quantitatively present the cytochrome oxidase reactivity of mitochondria, and that the degree of enzyme activity may contribute to the identification of functional differences in sensory neurons.