Photoprotective Effect of Carpomitra costata Extract against Ultraviolet B-Induced Oxidative Damage in Human Keratinocytes

Natural marine products show various biological properties such as antiphotoaging, antioxidant, anticancer, and anti-inflammation. This study evaluated the protective effects of the brown alga Carpomitra costata (Stackhouse) Batters (Sporochnaceae) against ultraviolet B (UVB)-provoked damage in human HaCaT keratinocytes. C. costata extract (CCE) effectively reduced superoxide anion, hydroxyl radical, and UVB-stimulated intracellular reactive oxygen species (ROS) levels. CCE also restored the expression and activity of UVB-suppressed antioxidant enzymes. Furthermore, CCE decreased UVB-triggered oxidative damage to cellular components including DNA, protein, and lipid and defended the cells against mitochondrial membrane depolarization-medicated apoptosis. The results of this study indicate that CCE can safeguard human keratinocytes against UVB-induced cellular damage via a potent antioxidant mechanism. CCE may find utility as part of a therapeutic arsenal against the damaging effects of UVB radiation on the skin.

Oncologic outcomes of laparoscopic nephroureterectomy for pT3 upper urinary tract urothelial carcinoma

AIM

We present the oncologic outcomes of laparoscopic nephroureterectomy management of pT3 upper urinary tract urothelial carcinoma.

METHODS

Between October 2003 and January 2011, 50 patients with pT3 upper urinary tract urothelial carcinoma which had pathologically confirmed underwent laparoscopic nephroureterectomy at our institution. Demographic data, perioperative results, pathological findings and oncologic outcomes were reviewed and analyzed retrospectively.

RESULTS

There were 36 patients (72%) of high grade lesion and 14 patients (28%) of low grade lesion. Lymphovascular invasion was observed in 16 patients (32%) and the surgical margin was positive in one patient. N stage was pN0 in 16 (32%), pN1 in 3 (6%), pN2 in 1 (2%) and pN3 in 1 (2%). The 5-year overall survival rate was 52.6% and the 5-year cancer-specific survival rate was 65.3%. Overall recurrence developed in 23 patients. There were 10 patients (20%) of urothelial recurrence which were all occurred in the bladder at the mean period of 13.6 months, and 7 patients of them were invasive bladder cancer. There were 16 patients (32%) of non-urothelial recurrence developed at the mean period of 9.69 months. On multivariate analyses lymphadenopathy and lymph node involvement of cancer (N+) were identified as independent predictive factors for the cancer-specific survival, and concomitant bladder tumor, grade and lymphovascular invasion were identified as independent predictive factors for the overall recurrence free survival.

CONCLUSION

Laparoscopic nephroureterectomy in patients with high stage upper urinary tract urothelial carcinoma appear comparable to those of open surgery in the regard of oncologic outcomes.

Kinetics of chemical decolorization of the azo dye C.I. Reactive Orange 96 by sulfide

The mechanism of decolorization of azo dyes based on the extracellular chemical reduction with sulfide (H2S, HS-, S2-) was postulated for sulfate reducing environments. To design technical decolorization processes of textile wastewater treatment with sulfide produced by sulfate reducing bacteria (SRB), kinetics is of great significance. Batch experiments were made in order to investigate the kinetics of abiotic decolorization of the reactive mono-azo dye C.I. Reactive Orange 96 (RO 96) with sulfide, with varying pH. The decolorization of RO 96 by sulfide under the exclusion of O2 corresponded to first-order kinetics with respect to both dye and sulfide concentration. The decolorization of RO 96 with sulfide at neutral pH (7.1) was advantageous compared with that at pH for 4.1, 6.3, and 6.5. This is attributed to an increase in the fraction of HS- of total sulfide species at neutral pH. The rate constants k for the decolorization at 37 degrees C were obtained as 0.01 for pH = 4.1, 0.06 for pH = 6.3, 0.08 for pH = 6.5, and 0.09 for pH = 7.1 in mM(-1) min(-1). The high rate constants for sulfide at pH 6.5-7.1 support that the decolorization through SRB (i.e. by bio-sulfide) can be effective in anaerobic bacterial systems with sulfate.

Noble 2-[3-(cyclopentyloxy)-4-methoxyphenyl]-1-isoindolinone derivatives. part I: synthesis and SAR studies for the inhibition of TNF-alpha production

This study describes the synthesis and in vitro evaluation of noble 2-[3-(cyclopentyloxy)-4-methoxyphenyl]-1-isoindolinone derivatives for the inhibition of TNF-alpha production. Among these compounds, 2-[3-(cyclopentyloxy)-4-methoxyphenyll-3-methyl-1-isoindolinone (5) was the most potent in inhibitory activity of TNF-alpha production in LPS-stimulated RAW264.7 cells.

In-vitro and in-vivo immunomodulatory effects of syringin

Syringin was found to possess immunomodulatory activity by which it inhibited the in-vitro immunohaemolysis of antibody-coated sheep erythrocytes by guinea-pig serum through suppression of C3-convertase of the classical complement. In this study, we examined its in-vitro and in-vivo activity on tumour necrosis factor (TNF)-alpha and nitric oxide (NO) production, CD4+ T cell and CD8+ cytotoxic T cell (CTLL-2) proliferation, and croton oil-, arachidonic acid- and fluorescein-isothiocynate (FITC)-induced mouse ear oedema model. Syringin significantly inhibited both TNF-alpha production from lipopolysaccharide (LPS)-stimulated RAW264.7 cells and CD8+ T cell (CTLL-2) proliferation in a dose-dependent manner, whereas neither NO production nor CD4+ T cell proliferation were blocked even by high concentrations of syringin. In the invivo experiments, syringin also significantly suppressed FITC-induced ear oedema in mice but not the ear oedema induced by croton or arachidonic acid. These results suggest that syringin may be implicated as an immunomodulator having an anti-allergic effect rather than an anti-inflammatory effect. The anti-allergic effect of syringin seems to be due, in part, to inhibition of TNF-alpha production and cytotoxic T cell proliferation.

In vitro inhibitory effect of protopanaxadiol ginsenosides on tumor necrosis factor (TNF)-alpha production and its modulation by known TNF-alpha antagonists

Ginsenosides are the major principles of Panax ginseng C. A. Meyer (Araliaceae) used as a mild oriental folk medicine. In this report, we have examined the inhibitory potency of protopanaxadiol ginsenosides (PPDGs) such as Rb1, Rb2 and Rc, and their co-treatment effect with known tumor necrosis factor (TNF)-alpha antagonists on TNF-alpha production in either murine (RAW264.7) or human (U937) macrophages stimulated with lipopolysaccharide (LPS). Rb1, and Rb2 strongly suppressed TNF-alpha production in RAW264.7 cells with an IC50 of 56.5 and 27.5 microM, respectively, and in differentiated U937 cells with an IC50 of 51.3, and 26.8 microM, respectively. The inhibitory activity of Rb1 and Rb2 was significantly increased by pharmacological agents against protein kinase C, protein tyrosine kinase, and protein kinase A, and anti-rheumatoid arthritis drugs, such as chloroquine and steroid drugs. In contrast, only cyclic AMP phosphodiesterase (cAMP PDE) inhibitors among cAMP-elevating agents did not change the inhibitory potency of PPDGs. These data suggest that PPDGs may possess potential therapeutic efficacy against TNF-alpha mediated disease and the therapeutic potency of PPDGs may be enhanced when co-treated with various kinds of known TNF-alpha antagonists but not with cAMP PDE inhibitors.

Savinin, a lignan from Pterocarpus santalinus inhibits tumor necrosis factor-alpha production and T cell proliferation

Two lignans were isolated from the heartwood of Pterocarpus santalinus by activity-guided fractionation and investigated for their biological properties and molecular mechanism of action. On the basis of their spectroscopic data, these compounds were identified as savinin (1) and calocedrin (2), dibenzyl butyrolactone-type lignan compounds having an alpha-arylidene gamma-lactone structure. These lignans significantly inhibited tumor necrosis factor (TNF)-a production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and T cell proliferation elicited by concanavalin (Con A), without displaying cytotoxicity. The molecular inhibitory mechanism of compound 1 was confirmed to be mediated by the non-polar butyrolactone ring, according to a structure-relationship study with structurally related and unrelated compounds, such as arctigenin (a dibenzyl butyrolactone type lignan), eudesmin (a furofuran type lignan), isolariciresinol (a dibenzylbutane type lignan), and cynaropicrin (a sesquiterpene lactone). The results suggest that savinin may act as an active principle in the reported biological activities of P. santalinus, such as antiinflammatory effect, by mediation of the butyrolactone ring as a valuable pharmacophore.

Hepatoprotection by human epidermal growth factor (hEGF) against experimental hepatitis induced by D-galactosamine (D-galN) or D-GalN/lipopolysaccharide

The hepatoprotecive effects of recombinant human epidermal growth factor (hEGF) on chemically and immunologically induced experimental liver injury models were examined. The hEGF clearly decreased serum transaminase levels in D-galactosamine (D-GalN) and D-GalN/lipopolysaccharide (LPS)-induced liver injury models under sub-lethal conditions. However, it has not significantly changed either serum or in vitro tumor necrosis factor (TNF)-alpha production or in vitro nitric oxide (NO) production, suggesting that the hepatoprotection by EGF is not mediated by inhibiting these pathological mediators produced in D-GalN and D-GalN/LPS-induced liver injury.

Mobilization kinetics of CD34(+) cells in association with modulation of CD44 and CD31 expression during continuous intravenous administration of G-CSF in normal donors

The aim of the present study is to evaluate the kinetics of CD34(+) cells and investigate the potential modulation of CD44 and CD31 expression on CD34(+) cells during continuous i.v. administration of G-CSF, thus to elucidate the possible mechanism of peripheral blood progenitor cell (PBPC) mobilization. Fifteen healthy donors were enrolled in this study. G-CSF (10 microg/kg/day) was administered for four consecutive days through continuous 24-h i.v. infusion. For measurement of complete blood counts, CD34(+) cell levels and their expression of CD44 and CD31, PB sampling was performed immediately before the administration of G-CSF (steady-state) and after 4, 8, 24, 48, 72, 96, and 120 h of G-CSF administration. The percentage and absolute number of CD34(+) cells significantly increased at day 3 (0. 55 +/- 0.09%, 51.12 +/- 24.83 x 10(3)/ml) and day 4 (0.47 +/- 0.09%, 46.66 +/- 24.93 x 10(3)/ml), compared to the steady-state level (0. 06 +/- 0.09%, 2.03 +/- 5.69 x 10(3)/ml). At day 3 to day 5 following the onset of G-CSF administration, a strong decrease of CD44 and CD31 expression was observed on mobilized CD34(+) cells compared to controls: the relative fluorescence intensity of CD44 and CD31 was, respectively, 50%-70% and 40%-90% lower than that of controls. We conclude that continuous i.v. administration of G-CSF apparently results in more rapid mobilization of CD34(+) cells, and downregulation of CD44 and CD31 on CD34(+) cells is likely to be involved in the mobilization of PBPC after treatment with G-CSF.

In vitro antiinflammatory effects of neolignan woorenosides from the rhizomes of Coptis japonica

Five dihydrobenzofuran neolignans, woorenosides I (1), II (2), III (3), IV (4), and V (5), isolated from Coptis japonica (Ranunculaceae), suppressed tumor necrosis factor (TNF)-alpha and nitric oxide (NuOmicron) production, as well as lymphocyte proliferation triggered by inflammatory signals such as various mitogens, in a dose-dependent manner. The results indicate that the woorenosides strongly inhibit the mitogenic response by activated macrophage and lymphocytes and suggest that these compounds may participate in regulating inflammatory processes.

Synthesis and structure-activity relationships of novel compounds for the inhibition of TNF-alpha production

This study describes the synthesis, in vitro evaluation and molecular modeling study of novel compounds for the inhibition of TNF-alpha production. Among these compounds, 2-[3-(cyclopentyloxy)-4-methoxyphenyl]-1-isoindolinone (9) was selected as a lead compound and its pyridine derivative 10 was more potent in activity and safer than rolipram.

Inhibitor of tumor necrosis factor-alpha production in lipopolysaccharide-stimulated RAW264.7 cells from Amorpha fruticosa

Certain flavonoids were reported to show an immunoregulatory activity against lymphocyte proliferation and cytokine production. In the course of a search for tumor necrosis factor (TNF)-alpha inhibitory compounds from natural plants, we also isolated a prenylfavanone type of flavonoid, amoradicin, from the extract of Amorpha fruticosa by activity-guided fractionation. This compound significantly inhibited TNF-alpha production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells with an IC(50) value of 28.5 microM. The activity was comparable or higher than those of standard flavonoid compounds, genistein and silybin with IC(50) of 24.9 and 140.3 microM, respectively.

Immunomodulatory effect of arctigenin, a lignan compound, on tumour necrosis factor-alpha and nitric oxide production, and lymphocyte proliferation

We have investigated the immunomodulatory effects of arctigenin, a dibenzyl butyrolactone lignan compound, on tumour necrosis factor (TNF)-alpha and nitric oxide (NO) production, and lymphocyte proliferation. Arctigenin inhibited strongly TNF-alpha production by lipopolysaccharide-stimulated murine macrophage RAW264.7 and differentiated human macrophage U937 with IC50 values of 5.0 and 3.9 microM, respectively, without displaying cytotoxicity. The TNF-alpha inhibitory effect of arctigenin in lipopolysaccharide-triggered RAW264.7 cells was increased by co-treatment with several known TNF-alpha inhibitors. It also potently attenuated T and B cell proliferation stimulated by concanavalin A and lipopolysaccharide in a dose-dependent manner with IC50 values of 2.9 and 14.6 microM, respectively. In contrast, the compound showed a different pattern in lipopolysaccharide- and interferon (IFN)-gamma-induced NO production from RAW264.7 cells. Arctigenin inhibited NO release by IFN-gamma signal, whereas it significantly enhanced lipopolysaccharide-triggered NO production in RAW264.7 cells. The results suggested that arctigenin may regulate immune responses in activated macrophages and lymphocytes including TNF-alpha and NO production and lymphocyte proliferation.

Distinct patterns of apoptosis in association with modulation of CD44 induced by thrombopoietin and granulocyte-colony stimulating factor during ex vivo expansion of human cord blood CD34+ cells

The insufficient number of haemopoietic stem cells (HSCs) in cord blood (CB) is the major potential limitation to widespread use of CB for marrow replacement. Cytokine-mediated ex vivo expansion has been proposed as a means of increasing the number of CB HSCs for transplantation. However, the biology of CB HSCs during cytokine-mediated ex vivo expansion, such as apoptosis or expression of adhesion molecules, has not yet been elucidated. We have investigated the patterns of apoptosis and CD44 expression on human CB CD34+ cells during ex vivo expansion. CD34+ cells isolated from human CB were cultured in a stroma-free liquid culture system with thrombopoietin (TPO), flt3-ligand (FL), stem cell factor (SCF), and/or granulocyte-colony stimulating factor (G-CSF). During the culture, for up to 5 weeks, apoptosis was measured by staining with 7-amino-actinomycin D (7-AAD) along with concurrent immunophenotyping of CD34 and CD44 with three-colour flow cytometry. In the cultures with TPO, an apoptotic fraction with down-regulated CD44 appeared from the fourth day up to the second week. G-CSF also induced apoptosis but in a different manner; the apoptotic fraction without down-regulation of CD44 appeared unremittingly for up to 5 weeks. FL did not induce apoptosis or down-regulation of CD44. These findings show that apoptosis is indeed involved in the regulation of CB CD34+ cells in ex vivo expansion and the patterns of apoptosis are dependent on the type of cytokines used. The distinct patterns of apoptosis suggest different mechanisms of TPO and G-CSF in inducing apoptosis, which still remains to be elucidated.

Eudesmin inhibits tumor necrosis factor-alpha production and T cell proliferation

Possible antiinflammatory effects of eudesmin were examined by assessing the effects on tumor necrosis factor (TNF)-alpha production and lymphocyte proliferation as well as cytotoxicity against murine and human macrophages. The compound significantly inhibited TNF-alpha production by lipopolysaccharide (LPS)-stimulated murine macrophage RAW264.7 without displaying cytotoxicity suggesting that eudesmin may inhibit TNF-alpha production without any interference of normal cell function. It also significantly attenuated T cell proliferation stimulated by concanavalin A (Con A) in a dose-dependent manner.

Myeloid differentiation of human cord blood CD34+ cells during ex vivo expansion using thrombopoietin, flt3-ligand and/or granulocyte-colony stimulating factor

We investigated the phenotypic changes of human umbilical cord blood (CB) CD34+ cells during ex vivo expansion using thrombopoietin (TPO), flt3-ligand (FL), and/or granulocyte-colony stimulating factor (G-CSF). During ex vivo expansion of CD34+ cells isolated from human CB for up to 5 weeks, surface expression of molecules on the cultured cells including CD64 (Fc gammaRI), CD32 (Fc gammaRII), CD16 (Fc gammaRII), CD11b (MAC-1) and CD18 (beta2-integrin) was analysed by flow cytometry along with simultaneous measurement of apoptosis by 7-aminoactinomycin D staining method. CD64, CD32 and/or CD18 expressing cells appeared in the cultures both with and without the addition of G-CSF until the tenth day. However, without G-CSF, CD16+ fractions did not appear and CD11b+ fractions were not maintained. With G-CSF, the CD16+ or CD11b+ fractions appeared only from the second week. These results suggest that G-CSF is necessary for the late stage of myeloid maturation during which CD16 and CD11b are expressed.

Inhibitory effect of sesquiterpene lactones from Saussurea lappa on tumor necrosis factor-alpha production in murine macrophage-like cells

Total methanol extract of Saussurea lappa radix (Compositae) showed potent inhibitory effect on the production of tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, in murine macrophage-like cell (RAW264.7 cells) in our previous screening studies on 120 Korean medicinal plants. The activity-guided purification of the plant resulted in the isolation of three components. The chemical structures of the components isolated were established by spectroscopic analyses as sesquiterpene lactones [cynaropicrin (1), reynosin (2), and santamarine (3)]. These three compounds inhibited TNF-alpha production in a dose-dependent manner. The molar concentrations of cynaropicrin, reynosin, and santamarine producing 50% inhibition (IC50) of TNF-alpha production were 2.86 micrograms/ml (8.24 microM), 21.7 micrograms/ml (87.4 microM), and 26.2 micrograms/ml (105 microM), respectively. However, treatment with sulphydryl (SH) compounds such as L-cysteine, dithiothreitol, and 2-mercaptoethanol abrogated the inhibitory effect of cynaropicrin on TNF-alpha production. Therefore, we conclude that the principal inhibitory component of Saussurea lappa is cynaropicrin and its inhibitory effect is mediated through conjugation with SH-groups of target proteins.

Inhibitory effect of lignans from the rhizomes of Coptis japonica var. dissecta on tumor necrosis factor-alpha production in lipopolysaccharide-stimulated RAW264.7 cells

The inhibitory effect of 10 lignan constituents isolated from the rhizomes of Coptis japonica var. dissecta on tumor necrosis factor (TNF)-alpha production in lipopolysaccharide (LPS)-stimulated macrophage cell line (RAW264.7 cells) has been studied. Among them, pinoresinol, woorenoside-V and lariciresinol glycoside showed significant inhibitory activities in the range from 37% to 55% at the concentration of 25 micrograms/ml. The results are first report that the lignans isolated from Coptis japonica inhibit TNF-alpha production, and suggest that the lignan components may partly participate in antiinflammatory and antiallergic effect of Coptis japonica through the inhibition of TNF-alpha production.

Isolation and identification of inhibitory compounds on TNF-alpha production from Magnolia fargesii

Three TNF alpha-inhibitory lignans were isolated from the flower buds of Magnolia fargesii through bioassay-guided isolation. They were identified as eudesmin, magnolin and lirioresinol-B dimethylether on the basis of their spectroscopic data. All three lignans showed inhibitory effects on TNF-alpha production in LPS-stimulated murine macrophage cell line, RAW264.7 and eudesmin showed the strongest activity (IC50 = 51 microM).

First-onset schizophrenia in the community: relationship of urbanization with onset, early manifestations and typology

As part of a World Health Organization collaborative study in 12 centres in developing and developed countries within defined urban and rural catchment areas with populations of 348,786 and 103,865, respectively, a total of 155 and 54 cases of first-onset schizophrenia, respectively, were identified over a 24-month period by a comprehensive and active recruitment of all cases. Approximately 50% of the subjects in both cohorts were in the age range of 15-24 years. There was a preponderance of males in the younger age group and of females in the older age group. The majority of cases had no family history and had shown good adjustment in childhood and adolescence. The onset was much more frequently acute and much less often insidious in our samples and (more so in the rural cohort), compared to the figure for all developed countries' sites. With regard to early manifestations of the disorder, there was a much higher incidence of loss of interest in appearance and cleanliness, being irritable and angry without reason, and loss of appetite, sleep or interest in sex in both of our samples, and of being excited or overactive for days or weeks in our rural cohort than in the developed countries' centres as a whole. On the other hand, claiming impossible things, behaving as if hearing voices and feeling persecuted, harmed or bewitched were much less frequent in our rural cohort than in the urban cohort or the developed countries' centres as a whole. With regard to the clinical diagnosis of schizophrenia, paranoid, hebephrenic/disorganized and residual types were under-represented in our samples (more so in the rural sample), and catatonic type and acute schizophrenic episode were over-represented compared to the developed countries' centres. Moreover, the proportion of subjects of CATEGO class S+ was lower in our samples. With regard to onset, early manifestations and clinical subtypes of schizophrenia, our rural cohort deviated most from developed countries' centres as a whole, with our urban sample falling in between, thus indicating the role of socio-cultural factors in general, and urbanization in particular, in these variables in schizophrenia.

Clinical trial of low dose cytosine arabinoside in the treatment of acute promyelocytic leukemia

The purpose of this study is to determine the efficacy of low dose cytosine arabinoside (LD Ara-C) as an alternative treatment to conventional cytotoxic induction chemotherapy in childhood acute promyelocytic leukemia (APL). Four children with APL in poor medical condition prior to chemotherapy were treated with LD Ara-C (10 mg/m2/12 h) for 3 weeks. In three patients, the second course was administered after a resting period of two weeks. Subsequent conventional cytotoxic induction chemotherapy was applied in patients who did not enter complete remission (CR). After induction of CR, maintenance chemotherapy with a conventional monthly multi-drug regimen was applied. CR in one patient and partial remission (PR) in two patients were obtained after two courses of LD Ara-C. Patients who did not enter CR after LD Ara-C entered on subsequent conventional chemotherapy. There were no major complications such as intracranial hemorrhage and sepsis; myelosuppression was not as severe as in conventional chemotherapy; there was clinical and laboratory improvement in coagulopathy. We concluded that LD Ara-C may be an alternative treatment to the conventional chemotherapy in children with APL, especially in whom conventional cytotoxic induction chemotherapy is thought to increase the risk of serious complications and early fatality during induction chemotherapy.

A case of systemic lupus erythematosus developing two years after remission of thrombotic thrombocytopenic purpura

We describe a 17-year-old male who presented with thrombotic thrombocytopenic purpura (TTP) and 2 years thereafter developed central nervous system lupus and nephritis. The association of TTP and systemic lupus erythematosus has been described, but the unusual sequence and chronological separation is very rare.

Course and outcome of acute non-organic psychotic states in India

This paper presents an overview of the diagnoses and short-term course of acute psychotic illnesses--affective as well as nonaffective--in a developing country setting. In the Chandigarh Acute Psychosis Study (CAPS) in Northern India, a cohort of 91 cases of acute psychotic illness were assessed for symptoms, diagnosis, and course ratings at multiple intervals over a 12 month period; cases were drawn from a rural and an urban clinic, permitting comparison of patients in these two settings. Non-affective (mainly schizophrenic) patients were found to be the predominant group (51%), followed by manic (26%), and depressive (19%) patients. Overall the acute psychoses had an excellent short-term course and outcome, a result which held across all diagnostic groups and both the rural and urban setting. Rural and urban patients were similar in diagnostic distribution and course of illness. Investigations of such cases can expand our view of the possible manifestations and course of psychotic disorders, and may have implications for diagnosis.

Modification of atracurium or vecuronium blockade and their reversal by succinylcholine in the cat

The interaction between succinylcholine (SCC) and non-depolarizers, atracurium or vecuronium was investigated in 36 cats of either sex using the sciatic nerve-anterior tibialis muscle preparation. Additionally, the relation of SCC to pseudocholinesterase activity was examined. The duration of action of vecuronium (6.5 +/- 1.3 to 7.3 +/- 2.2 minutes) in cats pretreated with SCC was greater than those (2.0 +/- 0.6 minutes) in non-pretreated cats. However, SCC had no influence on the duration of atracurium. The serum pseudocholinesterase activity was decreased after the injection of atracurium or neostigmine in contrast to vecuronium. The authors conclude that the prior administration of SCC prolongs the duration of vecuronium but not that of atracurium, and pseudocholinesterase activity is not related to the prolonging effect of SCC.

Neurotoxicity and long lasting analgesia induced by capsaicinoids

Administration of capsaicin (8-methyl-N-vanillyl-6-nonenamide) to neonatal rats gives a long-lasting insensitivity to chemical irritants, and its potential as a specific toxin for peripheral C-fibers has made it of particular interest to neurobiologists concerned with pain mechanisms. The existence of capsaicin receptor on primary afferent sensory neurons is now evident. To deduce a receptor model for capsaicin, and propose the possible molecular interactions at the site of action, we prepared more than 50 capsaicin congeners (capsaicinoids). With these capsaicinoids, we investigated the role of functional groups in producing the long-lasting analgesia by phenylquinone writhing test and Randall-Selitto's method with ICR mice and SD rats. The structure-activity relationship of capsaicin in producing analgesia was established as follows: proper length of hydrophobic alkyl chain is 8-18 carbon atoms; 3-methoxy group of aromatic ring plays an important role but not essential; the presence of phenolic-OH is indispensable and the most suitable site is para-position; acyl amide linkage is dispensable; the linkage of amide bond bridged to the ring with CH2 is appropriate. Depletion of substance P from spinal cord and dorsal horn of rats by capsaicinoids was proved by RIA and immunohistochemistry. We succeeded in eliminating a potent acute toxicity shown by capsaicin through its structural modification.