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PubMed1999

Characterization of partially transesterified poly(beta-hydroxyalkanoate)s using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was used for the characterization of a partially transesterified poly(beta-hydroxyalkanoate), PHA, polymer produced by the bacterial strain Alcaligenes eutrophus using saponified vegetable oils as the sole carbon sources. The transesterification was carried out separately under acidic and basic conditions to obtain PHA oligomers weighing less than 10 kDa. The intact oligomers were detected in their cationized [M + Na](+) and [M + K](+) forms by MALDI-TOFMS. A composition analysis, using the MALDI-TOF spectra, indicate that the oligomers obtained via acid catalysis were terminated with a methyl 3-hydroxybutyrate end group, and those obtained by base catalysis had a methyl crotonate (olefinic) termination. In addition to HB (hydroxy butyrate), the oligomers were found to contain a small percentage of HV (hydroxy valerate). This was independently confirmed using gas chromatography/mass spectrometry (GC/MS). In comparison, the analysis of a commercial PHA polymer, transesterified under identical conditions, only showed the presence of HB, i.e. a pure PHB homopolymer. Copyright 1999 John Wiley & Sons, Ltd.

Journal Article↗
PubMed2000

Ethnomedicinally selected plants as sources of potential analgesic compounds: indication of in vitro biological activity in receptor binding assays.

A number of plant species used in traditional medicine for the relief of pain have been selected from the medicinal and scientific literature of China, South America, Asia and West Africa. Extracts were prepared and tested in three in vitro receptor radioligand binding assays to determine whether there was an indication of biological activity, in particular their selectivity to a single receptor implicated in the mediation of pain. The three neuropeptide receptors chosen were Bradykinin (BK II), expressed in Chinese hamster ovary cells (CHO), neurokinin 1 (NK 1) expressed in astrocytoma cells, and calcitonin gene related peptide (CGRP) which were all implicated in the mediation of acute pain in the mammaliancentral nervous system. The plant species chosen to investigate were Ageratum conyzoides, Barringtonia edulis, Croton tiglium, Ipomea pes-caprae, Panax ginseng, Physostigma venenosum, Sinomenium acutum, Solidago virgaurea, Symplocos leptophylla and Typhonium giganteum. The results showed that there was a strong indication of biological activity for some of the plants which are used ethnomedicinally to treat pain, in the three in vitro receptor binding assays used, and particular plant extracts exhibited selective action to a single receptor.

Analgesics, Non-Narcotic↗
PubMed2000

Deficiency of IL-2 or IL-6 reduces lymphocyte proliferation, but only IL-6 deficiency decreases the contact hypersensitivity response.

We evaluated the importance of IL-2 and IL-6 in primary antigen-induced proliferation of lymph node cells (LNC) and the induction of contact hypersensitivity (CH). These responses were examined in cytokine-deficient mice following application of the contact sensitizer, oxazolone (OX). Proliferation and induction of IL-6 by LNC from IL-2-deficient (IL-2(-/-)) mice were reduced by approximately 95 %, relative to the proliferation of LNC from IL-2(+/+) mice, although induction and elicitation of CH responses was not significantly affected. In contrast, the proliferation of LNC from sensitized IL-6(- /-) mice was reduced by approximately 50% and the CH response was significantly reduced, relative to responses of IL-6(+/+) mice. Although nonspecific inflammatory responses induced by croton oil were similar in IL-6(+/+) and IL-6(-/-) mice, both the acute inflammatory response to OX and the second phase of the inflammatory response were significantly reduced. Thus IL-2 and IL-6 play a significant role in the total proliferative response of LNC following primary contact sensitization. However, the proliferation they promote is not critical for priming the antigen-specific effector cells responsible for eliciting CH responses and IL-6 appears to be more important for expression of the later phases of acute inflammation and the CH induced by OX.

Animals↗
PubMed1978

Formation and properties of reactive aldehydes.

4-Hydroxyalkenals react easily with SH groups in enzymes and structural proteins to give stable adducts in which the aldehyde is bound through a thioether linkage to the protein. This reaction represents the mechanism by which these compounds block certain metabolic processes (DNA, RNA and protein synthesis, respiration, glycolysis) and exert their antitumour activity. A highly significant inverse correlation exists between the number of hydroxypentenal-sensitive SH groups in the soluble proteins and the doubling time of 12 transplantable animal tumours. Hydroxyalkenals applied peritumourally completely prevent or significantly delay growth of the solid forms of four animal tumours. The almost non-toxic adducts of 4-hydroxypentenal-cysteine 1:1 and crotonal-cysteine 1:2 applied intraperitoneally prevent or inhibit growth of Ehrlich ascites tumour in mice. The possible formation of unsaturated aldehydes in vivo from lipids, carbohydrates and diamines is discussed.

Aldehydes↗
PubMed2005

Improved anti-inflammatory activity of three new terpenoids derived, by systematic chemical modifications, from the abundant triterpenes of the flowery plant Calendula officinalis.

Rings A, D and E of faradiol (1), and ring E of both arnidiol (10) and calenduladiol (4) have been subjected to various selective chemical manipulations to modify polarity, water affinity, H-bonding, sterics, and number of aromatic groups of these anti-inflammatory natural compounds. A total of 15 new and four known pentacyclic triterpenoids have been obtained in this way. Some 13 terpenoids were evaluated for their topical anti-inflammatory activities with respect to inhibition of croton oil induced ear oedema in mouse. Three derivatives of 1, the C(16) benzyl ether 15, the C(30) aldehyde 24, and the C(30) primary alcohol 25 showed significantly improved anti-inflammatory potencies, which is relevant for (future) structure-activity-relationship (SAR) studies.

Animals↗
PubMed1997

Cyclophosphamide-induced blood and tissue eosinophilia in contact sensitivity: mechanism of hapten-induced eosinophil recruitment into the skin.

The mechanism leading to selective production and accumulation of eosinophils in certain allergic skin diseases is unknown. Cyclophosphamide treatment (150 mg/kg) of BALB/c mice 48 h before sensitization with picryl chloride (PCl) resulted in striking blood and tissue eosinophilia, maximal at 13 days. Blood eosinophilia was not induced by the sensitization with oxazolone and 2,4-dinitrofluorobenzene. Challenge with 1 % PCl, but not croton oil caused preferential eosinophil accumulation into the dermis, which was associated with the enhanced expression of vascular cell adhesion molecule 1 (VCAM-1) on endothelial cells. Intravenous administration of anti-VCAM-1 monoclonal antibody abrogated eosinophil infiltration. In this murine model, we examined the role of several cytokines, including chemokines in inducing selective tissue eosinophilia in vivo. Local administration of antibodies against interleukin (IL)-1beta, IL-4, tumor necrosis factor (TNF)-alpha, and RANTES, but not against IL-5 before challenge inhibited hapten-induced eosinophil recruitment. Intradermal injection of recombinant (r)IL-1beta, rIL-4, rTNF-alpha, rRANTES, and rMIP-1alpha induced marked eosinophil accumulation. Nonetheless, intradermal rIL-5 was not a chemoattractant for eosinophils in vivo. Our findings suggest that IL-1beta, IL-4, TNF-alpha, and RANTES contribute to the selective accumulation of eosinophils in contact sensitivity reaction. Although circulating IL-5 can activate eosinophils and prolong their survival, locally secreted IL-5 is not crucial for inducing eosinophil recruitment into the skin.

Animals↗
PubMed1997

Tumor necrosis factor (TNF) receptor type 1 (p55) is a main mediator for TNF-alpha-induced skin inflammation.

Tumor necrosis factor alpha (TNF-alpha) is a pleiotropic proinflammatory cytokine that elicits a large number of biological effects, including inflammatory and immunoregulatory responses. Biological activities of TNF-alpha are mediated by two distinct TNF receptors, p55 type 1 receptor (TNFR1) and p75 type 2 receptor (TNFR2). To determine the role of TNF-alpha in the induction of inflammatory responses in the skin, gene-targeted mutant mice lacking either TNFR1 or TNFR2 were painted with irritant chemicals. Both phenol and croton oil painting onto the ears induced less inflammation in TNFR1(-) mice than normal and TNFR2(-) mice. Intradermal injection of TNF-alpha (0.2-200 ng for 3 days) into the ear induced less inflammation in TNFR1(-) mice than in normal mice. TNFR2(-) mice developed a normal inflammatory reaction to high doses of TNF-alpha (20-200 ng for 3 days), while they showed minimal reactivity to low doses of TNF-alpha (0.2-2 ng for 3 days). TNF-alpha is known to trigger the release of a series of other cytokines and to induce the expression of cell adhesion molecules, thus contributing to the development of inflammation. The levels of protein and mRNA for interleukin (IL)-6 were elevated in keratinocytes from normal as well as TNFR2(-) mice after treatment with TNF-alpha, while keratinocytes from TNFR1(-) mice did not show any up-regulation of IL-6. TNF-alpha induced intercellular adhesion molecule (ICAM)-1 expression in the keratinocytes from normal and TNFR2(-) mice, but not in those from TNFR1(-) mice. These results indicate that TNFR1 is critical for induction of skin inflammation by TNF-alpha.

Administration, Topical↗
PubMed1988

The development of contact hypersensitivity in mouse skin is suppressed by tumor promoters.

The ability of tumor promoters to suppress the development of contact hypersensitivity (CHS) was assessed by the mouse ear swelling assay. Application of the complete or second stage tumor promoters phorbol-12-myristate-13-acetate (PMA, 2 micrograms), croton oil (1%), benzoyl peroxide (20 mg), mezerein (2 micrograms), or phorbol-12-retinoate-13-acetate (PRA, 2 micrograms) to the abdominal surface of CF-1 female mice for 1 week (three treatments) prior to the sensitization of the same location with 0.5% 1-chloro-2,4-dinitrobenzene (DNCB) resulted in a 50% suppression (p less than 0.05) of the CHS response to DNCB. The first stage tumor promoters 4-O-Me-PMA (80 micrograms), calcium ionophore A23187 (80 micrograms), hydrogen peroxide (15%) and the non-promoting analogs phorbol-12,13-diacetate (PDA, 20 micrograms), phorbol (80 micrograms) or acetone did not suppress the response. The suppression of the development of CHS caused by PMA was dependent on the promoter being applied at the site of induction and was inhibited by application of the phospholipase A2 inhibitor dibromoacetophenone (100 micrograms), the lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA, 100 micrograms), or the antiinflammatory steroid fluocinolone acetonide (2 micrograms). Application of PMA or mezerein 24 h prior to challenge with DNCB, to the ears of mice previously sensitized with DNCB resulted in a significant enhancement of the ear swelling response by 60% and 110%, respectively, compared with controls. The results demonstrate that tumor promoters suppress the development of CHS, and suggest the possibility that second stage promotion may involve suppression of the development of a tumor specific immune response.

Animals↗
PubMed1979

South American plants II: taspine isolation and anti-inflammatory activity.

Croton lechleri L. (Euphorbiaceae), a plant from the Upper Amazon Valley of Peru, yielded the alkaloid taspine. The anti-inflammatory activity of taspine hydrochloride was studied using the carrageenan-induced pedal edema method, the cotton pellet-induced granuloma method, and the adjuvant polyarthritis model.

Alkaloids↗
PubMed2005

1H chemical shifts in NMR. Part 21--prediction of the 1H chemical shifts of molecules containing the ester group: a modelling and ab initio investigation.

The 1H NMR spectra of 24 compounds containing the ester group are given and assigned. These data were used to investigate the effect of the ester group on the 1H chemical shifts in these molecules. These effects were analysed using the CHARGE model, which incorporates the electric field, magnetic anisotropy and steric effects of the functional group for long-range protons together with functions for the calculation of the two- and three-bond effects. The effect of the ester electric field was given by considering the partial atomic charges on the three atoms of the ester group. The anisotropy of the carbonyl group was reproduced with an asymmetric magnetic anisotropy acting at the midpoint of the carbonyl bond with values of Deltachi(parl) and Deltachi(perp) of 10.1 x 10(-30) and -17.1 x 10(-30) cm3 molecule(-1). An aromatic ring current (=0.3 times the benzene ring current) was found to be necessary for pyrone but none for maleic anhydride. This result was confirmed by GIAO calculations. The observed 1H chemical shifts in the above compounds were compared with those calculated by CHARGE and the ab initio GIAO method (B3LYP/6-31G**). For the 24 compounds investigated with 150 1H chemical shifts spanning a range of ca 10 ppm, the CHARGE model gave an excellent r.m.s. error (obs - calc) of <0.1 ppm. The GIAO calculations gave a very reasonable r.m.s. error of ca 0.2 ppm although larger deviations of ca 0.5 ppm were observed for protons near to the electronegative atoms. The accurate predictions of the 1H chemical shifts given by the CHARGE model were used in the conformational analysis of the vinyl esters methyl acrylate and methyl crotonate. An illustration of the use of the CHARGE model in the prediction of the 1H spectrum of a complex organic molecule (benzochromen-6-one) is also given.

Anisotropy↗
PubMed1980

Mutagenicity of vinyl compounds in Salmonella typhimurium.

Eighteen compounds structurally related to the mutagenic carcinogen vinyl chloride have been tested for mutagenicity in five strains of Salmonella typhimurium. Acrolein, acrolein diethylacetal, acrylonitrile, allyl alcohol, allyl bromide, crotonaldehyde, crotyl alcohol, and vinyl bromide were mutagenic with one or more strains; acrolein bisulfite, acrolein oxime, acrylamide, acrylic acid, allylamine, trans-cinnamaldehyde, trans-cinnamic acid, crotonic acid, methyl methacrylate, and vinyl acetate were not mutagenic. The mutagenicity tests were performed both without and with activation by rat and hamster liver microsomal preparations (S9). All compounds were tested in the plate incorporation and/or liquid preincubation tests except vinyl bromide, which was tested as a gas.

Animals↗
PubMed1998

Eubacterium aggreganssp. nov., a new homoacetogenic bacterium from olive mill wastewater treatment digestor.

A strictly anaerobic, homoacetogenic, gram-positive, non spore-forming bacterium, designated strain SR12(T) (T = type strain), was isolated from an anaerobic methanogenic digestor fed with olive mill wastewater. Yeast extract was required for growth but could also be used as sole carbon and energy source. Strain SR12(T) utilized a few carbohydrates (glucose, fructose and sucrose), organic compounds (lactate, crotonate, formate and betaine), alcohols (methanol), the methoxyl group of some methoxylated aromatic compounds, and H2 + CO2. The end-products of carbohydrate fermentation were acetate, formate, butyrate, H2 and CO2. End-products from lactate and methoxylated aromatic compounds were acetate and butyrate. Strain SR12(T) was non-motile, formed aggregates, had a G+C content of 55 mol % and grew optimally at 35 degrees C and pH 7.2 on a medium containing glucose. Phylogenetically, strain SR12(T) was related to Eubacterium barkeri, E. callanderi, and E. limosum with E. barkeri as the closest relative (similarity of 98%) with which it bears little phenotypic similarity or DNA homology (60%). On the basis of its phenotypic, genotypic, and phylogenetic characteristics, we propose to designate strain SR12(T) as Eubacterium aggregans sp. nov. The type strain is SR12(T) (= DSM 12183).

Journal Article↗
PubMed1993

Preliminary crystallographic studies of crotin II.

Crotin II isolated from the seeds of Euphorbiacea Croton tiglium has been crystallized. Crystals were grown by vapor diffusion using KCl as the precipitant. The crystal of crotin II belongs to the space group P6(1) or P6(5) with cell parameters a = b = 94.62 A, c = 28.43 A, alpha = beta = 90 degrees, gamma = 120 degrees. The asymmetric unit contains one molecule of 15,000 Da. A data set to 1.82 A has been collected on an area detector.

Crystallization↗
PubMed1991

Selective inhibition by magnosalin and magnoshinin, compounds from "Shin-i" (Flos magnoliae), of adjuvant-induced angiogenesis and granuloma formation in the mouse pouch.

Inhibitory effects of magnosalin and magnoshinin, compounds from the crude drug "Shin-i" (Flos magnoliae), on angiogenesis and pouch granuloma formation in mice induced by an adjuvant containing croton oil were investigated. The anti-chronic inflammatory effect of "shin-i" was caused by selective inhibition of angiogenesis by magnosalin and of granuloma formation by magnoshinin.

Animals↗
PubMed1991

Anaerobic degradation of sorbic acid by sulfate-reducing and fermenting bacteria: pentanone-2 and isopentanone-2 as byproducts.

Strictly anaerobic bacteria were enriched and isolated from freshwater sediment sources in the presence and absence of sulfate with sorbic acid as sole source of carbon and energy. Strain WoSo1, a Gram-negative vibrioid sulfate-reducing bacterium which was assigned to the species Desulfoarculus (formerly Desulfovibrio) baarsii oxidized sorbic acid completely to CO2 with concomitant stoichiometric reduction of sulfate to sulfide. This strain also oxidized a wide variety of fatty acids and other organic compounds. A Gram-negative rod-shaped fermenting bacterium, strain AmSo1, fermented sorbic acid stoichiometrically to about equal amounts of acetate and butyrate. At concentrations higher than 10 mM, sorbic acid fermentation led to the production of pentanone-2 and isopentanone-2 (3-methyl-2-butanone) as byproducts. Strain AmSo1 fermented also crotonate and 3-hydroxybutyrate to acetate and butyrate, and hexoses to acetate, ethanol, hydrogen, and formate. The guanine-plus-cytosine content of the DNA was 41.8 +/- 1.0 mol%. Sorbic acid at concentrations higher than 5 mM inhibited growth of this strain while strain WoSo1 tolerated sorbic acid up to 10 mM concentration.

Bacteria, Anaerobic↗
PubMed1996

Oral health status and treatment needs in immigrants and refugees in Italy.

The caries prevalence, oral hygiene status, periodontal health and the treatment needs were assessed in immigrants and refugees in Catanzaro and Crotone, Italy. The mean DMFT and DMFS scores of adults, 18 or more years, were 8.1 and 33.1 for Yugoslavs, 7.4 and 28.8 for Moroccans, and 1.4 and 4.5 for Senegalese. The analysis of variance carried out on the three groups showed a significant inequality in their DMFT and DMFS scores. The stepwise linear regression showed that in the Moroccans and Yugoslavs the DMFT increased with age. The needs for dental extractions and for conservative dental care were respectively 15.8% and 39.5% in the Senegalese, 28.6% and 73.8% in the Yugoslavs, 32.7% and 77% in the Moroccans. Good oral hygiene status was scored for 26.3% Senegalese, 7.1% Yugoslavs, and 5.5% Moroccans. Good periodontal health was scored for 7.9%, 2.4%, and 1.2% of these groups. The analysis of variance carried out on the three groups showed a significant inequality in their OHI-S and PI, and the Bonferroni test showed a significant differences in both indices comparing the Senegalese with the Moroccans and in the OHI-S between Senegalese and Yugoslavs. The stepwise linear regression showed that in the Yugoslavs the OHI-S and in the Moroccans and Yugoslavs the PI increased with age. The results of this investigation demonstrated high caries prevalence, poor oral hygiene and periodontal health, and unmet needs for dental treatment in particular Moroccans and Yugoslavs, and a systematic and comprehensive implementation of oral health promotion program for these groups is a priority need.

Adolescent↗
PubMed1990

On the history of deformation phosphenes and the idea of internal light generated in the eye for the purpose of vision.

Deformation phosphenes are light sensations evoked by deformation of the eyeball in total darkness. They were first reported in Western literature by Alcmaeon of Croton in the fifth century B.C. The phenomenon of deformation phosphenes was instrumental in prompting some pre-Socratic philosophers and Plato to conceive the idea that efferent light is emitted from the eye for the purpose of vision and a 'cone of vision' is formed by interaction with the external light. In the theories of vision this cone of vision played an important role as a signal-transmitting structure and was also used by the Greek opticians as a geometrical construction to explain optical properties of vision. The impact of the deformation phosphene experiment on the ideas of visual sensation can be followed from Greek antiquity through the period of Roman dominance and Galen's medical teaching on to medieval times and up to the late Renaissance when, based on the anatomy of the eye as illustrated by Felix Platter, the image formation on the retina was correctly described for the first time by Johannes Kepler. In the generations following, deformation phosphenes were still employed as an important argument in defence of the theories of vision. However, the idea of physical light generated by eyeball deformation was rejected with increasing frequency during the 17th and 18th centuries. The literature on this topic is discussed, comprising the contributions of the Arabic philosophers and physicians of the 9th and 10th centuries A.D., the Franciscan and Dominican philosophers of the 13th century, Nicolaus Cusanus of the 15th century, several anatomists of the 16th and 17th centuries, Kepler, Plempius, Descartes, Boyle, Newton and others. After Kepler, the mechanical interpretation of the deformation phosphene being caused by direct action of the eyeball deformation onto the retina slowly became dominant, and the idea that physical light is generated in the eye disappeared. The experimentum crucis in this matter was performed by Giovanni Battista Morgagni (1682-1771) and repeated and extended by Georg August Langguth (1711-1782). On the basis of their results, the case for physical light being generated in the eye by deformation was refuted definitively and slowly vanished thereafter from scientific literature. Deformation phosphenes were used in the 19th and 20th centuries as an instructive example of the percepts evoked by inadequate stimulation of a sense organ. J.E. Pŭrkyne in particular contributed to the study of deformation phosphenes, and finally in 1978, F. Tyler devoted a careful study to the differences between monocular and binocular deformation phosphenes.(ABSTRACT TRUNCATED AT 400 WORDS)

History, 15th Century↗
PubMed1989

The effects of the anti-tumor agent mezerein on the cytotoxic capacity and oxidative metabolism of human blood cells.

Mezerein, the most active antitumor compound isolated from the daphne species of plants, has a structural similarity to phorbol myristate acetate (PMA), the major active compound isolated from croton oil. PMA is known to have tumor promoting activity and is a potent inflammatory agent. Mezerein has similarly been reported to have potent inflammatory properties but appears to be a weaker tumor promoter than PMA. While the effect of PMA on the function and metabolism of human blood cells has been extensively studied, there is little similar information concerning mezerein. Therefore, in these studies, we have compared the capacities of mezerein and PMA to activate the cytotoxic capacity and oxidative metabolism of human granulocyte (PMNs), monocyte, lymphocyte, and mononuclear cell (lymphocytes and monocytes) cultures in vitro. Mezerein stimulated the oxidative metabolism of PMNs in an identical manner to PMA as indicated by a burst in the activity of the HMPS pathway, the production of H2O2, hydroxyl radical and stable oxidants. Mezerein also stimulated the release of thromboxane B2 from PMNs. Both compounds activated the oxidative metabolism of monocytes but not the oxidative metabolism of lymphocytes. The enhanced oxidative metabolism of the phagocytic cells was associated with an increased cytotoxicity against human red cells which are sensitive to oxidant damage but not against the NK resistant Raji lymphoblast cell line or the SW1116 colon tumor cell line. Of interest is that mezerein did not augment significantly the minimal cytotoxic capacity (NK activity) of mononuclear cells, monocytes or freshly isolated lymphocyte cultures against the tumor cell targets used in our experiments. However, lymphocyte cultures preincubated for 15 hours with mezerein had a marked enhancement of cytotoxicity against the tumor targets. This activation was not observed in similarly treated mononuclear cell cultures suggesting a suppressor activity of the monocytes. Our data suggest that the potent inflammatory activity of mezerein similar to PMA, may be related to its capacity to activate the oxidative and arachidonic metabolism of phagocytic cells. In addition, the capacity of mezerein to activate the cytotoxic capacity of lymphocytes may relate to its reported in vivo antitumor activity.

Antineoplastic Agents, Phytogenic↗