A proline derivative-enriched methanol fraction from Sideroxylon obtusifolium leaves (MFSOL) stimulates human keratinocyte cells and exerts a healing effect in a burn wound model

It was previously demonstrated that the methanol fraction of Sideroxylon obtusifolium (MFSOL) promoted anti-inflammatory and healing activity in excisional wounds. Thus, the present work investigated the healing effects of MFSOL on human keratinocyte cells (HaCaT) and experimental burn model injuries. HaCaT cells were used to study MFSOL's effect on cell migration and proliferation rates. Female Swiss mice were subjected to a second-degree superficial burn protocol and divided into four treatment groups: Vehicle, 1.0% silver sulfadiazine, and 0.5 or 1.0% MFSOL Cream (CrMFSOL). Samples were collected to quantify the inflammatory mediators, and histological analyses were performed after 3, 7, and 14 days. The results showed that MFSOL (50 μg/mL) stimulated HaCaT cells by increasing proliferation and migration rates. Moreover, 0.5% CrMFSOL attenuated myeloperoxidase (MPO) activity and also stimulated the release of interleukin (IL)-1β and IL-10 after 3 days of treatment. CrMFSOL (0.5%) also enhanced wound contraction, promoted improvement of tissue remodeling, and increased collagen production after 7 days and VEGF release after 14 days. Therefore, MFSOL stimulated human keratinocyte (HaCaT) cells and improved wound healing via modulation of inflammatory mediators of burn injuries.

The vicious cycle of dental fear at age 31 in a birth cohort in Southern Brazil

OBJECTIVES

This longitudinal study assessed the prevalence of dental fear in adulthood and the association with socio-economic, behavioural and clinical variables. Also, the existence of a vicious cycle of dental fear was tested.

METHODS

A random sample of adults (n = 535) from the 1982 Pelotas Birth Cohort, Brazil, was selected. Socio-economic data, behavioural characteristics and clinical variables were collected during different cohort waves. Oral health data were collected at ages 15, 24 and 31 years old, using questionnaires and oral examination. Dental fear (the outcome) was assessed by the question: 'Are you afraid of going to the dentist?', with possible responses: dichotomized into 'No' or 'A little/Yes/A lot'. Exposure variables were as follows: dental visit in the last years (at the ages 15 and 31); caries experience (DMFT ≥ mean) at the ages 15 and 31; the trajectory of caries prevalence from 15 to 31 years old; dental pain in the last six months in the two ages evaluated; and self-rated oral health at age 31. Several multivariable Poisson regression models were used to investigate the association between each of the exposure variables and dental fear.

RESULTS

Dental fear prevalence was 22.1%, and it was more prevalent among non-white individuals and females. After controlling for potential confounders, dental fear was more likely to be reported by those individuals who had dental pain or a higher prevalence of dental caries at the age 15. Dental fear was also associated with a worse trajectory of dental caries, negative self-rated oral health at age 31 and with not having visited the dentist in the last year (at the age 31). Results supported the proposed vicious cycle of dental fear.

CONCLUSIONS

Dental fear in adulthood was related to exposures occurring across the lifecourse. Also, it was possible to observe the occurrence of the vicious cycle of dental fear in the 1982 Pelotas Birth Cohort. Therefore, preventive measures during different periods of the life course are required to prevent dental fear and adulthood.

The impact of cyberbullying on schoolchildren's dental anxiety in Brazil: A cross-sectional multi-level study

OBJECTIVES

This cross-sectional study assessed the correlation between individual and school-related social environment variables with dental anxiety in Brazilian schoolchildren aged 8-12 years.

METHODS

A sample of children from 20 private and public schools (n = 1211) from Pelotas, Brazil, were selected. Socioeconomic data were collected from parents, and data regarding children characteristics were collected using a questionnaire. Dental anxiety (the outcome) was assessed by the following question: 'Are you afraid of going to the dentist?' Dental examinations were performed to assess caries experience (DMFT ≥ 1). The social school environment was assessed by a questionnaire administered to schools' coordinators and considered: type of school, verbal violence between students, presence of gangs at school and cyberbullying episodes. Multilevel Poisson regression was used to investigate the association between school social environment and dental anxiety.

RESULTS

The prevalence of dental anxiety was 9.1% (95%CI 7.5-10.8). For the individual variables, anxiety was more prevalent in girls [1.85 (1.21-2.81)], in children with less-educated mothers [1.50 (1.00-2.27)] and in children who never attended to the dentist [2.48 (1.65-3.72)]. For contextual variables, episodes of cyberbullying in school increased the prevalence of dental anxiety by almost 80% [1.78 (1.14-2.78)].

CONCLUSIONS

The school social environment influences dental anxiety. The results suggest that it is important to establish strategies focused on promoting healthier environments and preventing cyberbullying in order to reduce the occurrence of dental anxiety.

Violacein antimicrobial activity on Staphylococcus epidermidis and synergistic effect on commercially available antibiotics

AIMS

The study aimed to assess whether violacein has antimicrobial activity on Staphylococcus epidermidis and synergistically modulates the action of commercially available antimicrobial drugs.

METHODS AND RESULTS

Violacein showed excellent antimicrobial activity on biofilm-forming and nonbiofilm-forming S. epidermidis strains (ATCC 35984) (ATCC 12228), with bacteriostatic (MIC = 20 μg ml^-1 and 10 μg ml^-1 respectively) and bactericidal effects (MBC = 20 μg ml^-1 for both strains), observed in short periods of exposure. The violacein bactericidal concentration led to S. epidermidis death after 2-3 h of exposure. Additionally, violacein synergistically modulated the activity of different antimicrobial classes on S. epidermidis ATCC 12228 (81·8%; n = 9) and on S. epidermidis ATCC 35984 (54·5%; n = 6), reducing the MIC of these antibiotics by up to 16-fold.

CONCLUSION

Violacein shows excellent antimicrobial activity on S. epidermidis strains.

SIGNIFICANCE AND IMPACT OF THE STUDY

Violacein shows the potential for the development of a new drug for the treatment of infections caused by S. epidermidis.

Developmental defects of enamel and dental caries in the primary dentition: A systematic review and meta-analysis

OBJECTIVES

This systematic review and meta-analysis evaluated the association between developmental defects of enamel and dental caries in the primary dentition.

SOURCES

Electronic searches were performed in PubMed, Web of Knowledge, Scopus and Scielo for the identification of relevant studies.

STUDY SELECTION

Observational studies that examined the association between developmental defects of enamel and dental caries in the deciduous dentition were included. Additionally, meta-analysis, funnel plots and sensitivity analysis were employed to synthesize the available evidence. Multivariable meta-regression analysis was performed to explore heterogeneity among studies.

DATA

A total of 318 articles were identified in the electronic searches. Of those, 16 studies were included in the meta-analysis. Pooled estimates revealed that children with developmental defects of enamel had higher odds of having dental caries (OR 3.32; 95%CI 2.41-4.57), with high heterogeneity between studies (I² 80%). Methodological characteristic of the studies, such as where it was conducted, the examined teeth and the quality of the study explained about 30% of the variability. Concerning type of defect, children with hypoplasia and diffuse opacities had higher odds of having dental caries (OR 4.28; 95%CI 2.24-8.15; OR1.42; 95%CI 1.15-1.76, respectively).

CONCLUSIONS

This systematic review and meta-analysis demonstrates a clear association between developmental defects of enamel and dental caries in the primary dentition.

A comparative chemical and pharmacological study of standardized extracts and vanillic acid from wild and cultivated Amburana cearensis A.C. Smith

The objectives of this work were to carry out a comparative chemical study and to evaluate the antinociceptive and anti-inflammatory activities of ethanol extracts (EtOHE) and vanilic acid (VA) from cultivated and wild Amburana cearensis A.C. Smith (Fabaceae), an endangered species used in Northeast Brazil for the treatment of asthma. The HPLC analysis of EtOHE, showed that coumarin (CM) and VA were the major constituents from the cultivated plant, while in the extract from the wild plant the major constituents were amburoside A (AMB) and CM. Pharmacological tests were performed with male Swiss mice or male Wistar rats acutely administered with 100-400mg/kg, p.o. of EtOHEs or 12.5-50mg/kg, p.o. of VA. EtOHEs from A. cearensis with 4, 7 or 9 months of cultivation significantly inhibited, from 32 to 64%, both phases of the formalin test in mice. Similar results were observed with the EtOHE from the wild species. VA significantly reduced both phases of the formalin test. This effect was partially reversed by naloxone. EtOHE from cultivated or wild A. cearensis inhibited the carrageenan (Cg)-induced mice paw edema. Furthermore, VA inhibited the paw edema and the leukocyte migration in rat peritoneal cavity induced by Cg. On the other hand, it did not inhibit the edema and the increase of vascular permeability induced by dextran in the rat paw. All together, these results indicate that the EtOHE from cultivated A. cearensis exhibit similar chemical and pharmacological profiles, as related to the wild plant. VA is, at least partially, responsible for these pharmacological effects. Its antinociceptive effect occurs by a mechanism partly dependent upon the opioid system, while the anti-inflammatory action was manifested in inflammatory processes dependent on polymorphonuclear cells and are probably related to the VA inhibition of cytokines as observed by others.

Structure-mutagenicity relationship of kaurenoic acid from Xylopia sericeae (Annonaceae)

Kaurane diterpenes are considered important compounds in the development of new highly effective anticancer chemotherapeutic agents. Genotoxic effects of anticancer drugs in non-tumour cells are of special significance due to the possibility that they induce secondary tumours in cancer patients. In this context, we evaluated the genotoxic and mutagenic potential of the natural diterpenoid kaurenoic acid (KA), i.e. (-)-kaur-16-en-19-oic acid, isolated from Xylopia sericeae St. Hill, using several standard in vitro and in vivo protocols (comet, chromosomal aberration, micronucleus and Saccharomyces cerevisiae assays). Also, an analysis of structure-activity relationships was performed with two natural diterpenoid compounds, 14-hydroxy-kaurane (1) and xylopic acid (2), isolated from X. sericeae, and three semi-synthetic derivatives of KA (3-5). In addition, considering the importance of the exocyclic double bond (C16) moiety as an active pharmacophore of KA cytotoxicity, we also evaluated the hydrogenated derivative of KA, (-)-kauran-19-oic acid (KAH), to determine the role of the exocyclic bond (C16) in the genotoxic activity of KA. In summary, the present study shows that KA is genotoxic and mutagenic in human peripheral blood leukocytes (PBLs), yeast (S. cerevisiae) and mice (bone marrow, liver and kidney) probably due to the generation of DNA double-strand breaks (DSB) and/or inhibition of topoisomerase I. Unlike KA, compounds 1-5 and KAH are completely devoid of genotoxic and mutagenic effects under the experimental conditions used in this study, suggesting that the exocyclic double bond (C16) moiety may be the active pharmacophore of the genetic toxicity of KA.

Genotoxic effects of tanshinones from Hyptis martiusii in V79 cell line

The genotoxic effect of two tanshinones isolated from roots of Hyptis martiussi Benth (Labiatae) was studied using V79 (Chinese hamster lung) cells by the alkaline comet assay and micronucleus test. Tanshinones were incubated with the cells at concentrations of 1, 3, 6 and 12 microg/mL for 3 h. Tanshinones were shown to be quite strongly genotoxic against V79 cells at all tested concentrations. The data obtained provide support to the view that tanshinones has DNA damaging activity in cultured V79 cells under the conditions of the assays.

Relaxant effects of an alkaloid-rich fraction from Aspidosperma ulei root bark on isolated rabbit corpus cavernosum

We described earlier that an alkaloid-rich fraction (F(3-5)) from Aspidosperma ulei (Markgr) induces penile erection-like behavioral responses in mice. This study verified a possible relaxant effect of this fraction on isolated rabbit corpus cavernosum (RbCC) strips precontracted by phenylephrine (1 microM) or K+ 60 mM. F(3-5) (1-300 microg ml(-1)) relaxed the RbCC strips in a concentration-dependent and reversible manner. The relaxant effect of F(3-5) (100 microg ml(-1)) on phenylephrine contraction was unaffected in the presence of atropine, N-omega-nitro-L-arginine methyl ester or 1H-[1,2,4]oxadiazole[4,3-a] quinoxalin-1-one and by preincubation with tetrodotoxin, glibenclamide, apamine and charybdotoxin suggesting that mechanisms other than cholinergic, nitrergic, sGC activation or potassium channel opening are probably involved. However, the phasic component of the contraction induced by K+ 60 mM as well as the maximal contraction elicited by increasing external Ca2+ concentrations in depolarized corpora cavernosa was inhibited by F(3-5). We conclude that F(3-5) relaxes the RbCC smooth muscle, at least in part, through a blockade of calcium influx or its function.

In vivo growth-inhibition of Sarcoma 180 by piplartine and piperine, two alkaloid amides from Piper

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} and piperine {1-5-(1,3)-benzodioxol-5-yl)-1-oxo-2,4-pentadienyl]piperidine} are alkaloid amides isolated from Piper. Both have been reported to show cytotoxic activity towards several tumor cell lines. In the present study, the in vivo antitumor activity of these compounds was evaluated in 60 female Swiss mice (N = 10 per group) transplanted with Sarcoma 180. Histopathological and morphological analyses of the tumor and the organs, including liver, spleen, and kidney, were performed in order to evaluate the toxicological aspects of the treatment with these amides. Administration of piplartine or piperine (50 or 100 mg kg(-1) day(-1) intraperitoneally for 7 days starting 1 day after inoculation) inhibited solid tumor development in mice transplanted with Sarcoma 180 cells. The inhibition rates were 28.7 and 52.3% for piplartine and 55.1 and 56.8% for piperine, after 7 days of treatment, at the lower and higher doses, respectively. The antitumor activity of piplartine was related to inhibition of the tumor proliferation rate, as observed by reduction of Ki67 staining, a nuclear antigen associated with G1, S, G2, and M cell cycle phases, in tumors from treated animals. However, piperine did not inhibit cell proliferation as observed in Ki67 immunohistochemical analysis. Histopathological analysis of liver and kidney showed that both organs were reversibly affected by piplartine and piperine treatment, but in a different way. Piperine was more toxic to the liver, leading to ballooning degeneration of hepatocytes, accompanied by microvesicular steatosis in some areas, than piplartine which, in turn, was more toxic to the kidney, leading to discrete hydropic changes of the proximal tubular and glomerular epithelium and tubular hemorrhage in treated animals.

Genotoxicity evaluation of kaurenoic acid, a bioactive diterpenoid present in Copaiba oil

Copaiba oil extracted from the Amazon traditional medicinal plant Copaifera langsdorffii is rich in kaurenoic acid (ent-kaur-16-en-19-oic acid), a diterpene that has been shown to exert anti-inflammatory, hypotensive, and diuretic effects in vivo and antimicrobial, smooth muscle relaxant and cytotoxic actions in vitro. This study evaluated its potential genotoxicity against Chinese hamster lung fibroblast (V79) cells in vitro, using the Comet and the micronucleus assays. Kaurenoic acid was tested at concentrations of 2.5, 5,10, 30 and 60 microg/mL. The positive control was the methylmethanesulfonate (MMS). The duration of the treatment of V79 cells with these agents was 3h. The results showed that unlike MMS, kaurenoic acid (2.5, 5, and 10 microg/mL) failed to induce significantly elevated cell DNA damage or the micronucleus frequencies in the studied tests. However, exposure of V79 cells to higher concentrations of kaurenoic acid (30 and 60 microg/mL) caused significant increases in cell damage index and frequency. The data obtained provide support to the view that the diterpene kaurenoic acid induces genotoxicity.

Antinociceptive effect of leaf essential oil from Croton sonderianus in mice

The leaf essential oil from Croton sonderianus (EOCS) was evaluated for antinociceptive activity in mice using chemical and thermal models of nociception. Given orally, the essential oil at doses of 50, 100 and 200 mg/kg produced significant inhibitions on chemical nociception induced by intraperitoneal acetic acid and subplantar formalin or capsaicin injections. However, it evidenced no efficacy against thermal nociception in hot-plate test. More prominent inhibition of acetic acid-induced writhing and capsaicin-induced hind-paw licking responses was observed at 100 and 200 mg/kg of EOCS. At similar doses, the paw licking behavior in formalin test was more potently suppressed during the late phase (20-25 min, inflammatory) than in early phase (0-5 min, neurogenic). The EOCS-induced antinociception in both capsaicin and formalin tests was insensitive to naloxone (1 mg/kg, s.c.), but was significantly antagonized by glibenclamide (2 mg/kg, i.p.). In mice, the essential oil (100 and 200 mg/kg) neither significantly enhanced the pentobarbital-sleeping time nor impaired the motor performance in rota-rod test, indicating that the observed antinociception is unlikely due to sedation or motor abnormality. These results suggest that EOCS produces antinociception possibly involving glibenclamide-sensitive KATP+ channels, which merit further studies on its efficacy in more specific models of hyperalgesia and neuropathic pain.

Amburoside A, a glucoside from Amburana cearensis, protects mesencephalic cells against 6-hydroxydopamine-induced neurotoxicity

This study evaluates the potential neuroprotective properties of amburoside A, a glucoside isolated from Amburana cearensis, on rat mesencephalic cell cultures exposure to the neurotoxin 6-hydroxydopamine (6-OHDA). The parameters determined were cell viability by the 3[4,5-dimethylthiazole-2-il]-2,5-diphenyltetrazolium bromide (MTT) method, nitric oxide (NO) and free radical formation by the measurement of nitrite concentration and thiobarbituric acid reacting substance (TBARS) formation as an indication of cellular lipid peroxidation. The results showed that AMB was less effective as a curative agent in the MTT assay, since its addition after 6-OHDA did not reverse the neurotoxin's effect, except at the highest concentration (AMB, 100 microg/ml). Similarly, the higher nitrite levels observed after exposure of the cells to 6-OHDA were only partially reversed by AMB, at this highest concentration. However, when AMB (0.5, 1, 10 and 100 microg/ml) was added before the toxin, it appeared to protect neuronal cells against 6-OHDA toxicity in a concentration-dependent manner, as shown by MTT assay. AMB also prevented free radical formation indicated by the increased nitrite concentration induced by 6-OHDA. Cells exposed to 6-OHDA showed a 3.4 times increase in TBARS concentration as compared to controls, and this effect was inhibited from 24% up to 64% by AMB (0.1-100 microg/ml), indicative of a neuroprotective effect. In conclusion, we show that AMB, acting as an antioxidant compound, presents a significant neuroprotective effect, suggesting that this compound could provide benefits as a therapeutic agent in neurodegenerative disease such as Parkinson's.

Total assignment of 1H and 13C NMR spectra of the alkaloid 3,3-diisopentenyl-N-methyl-2,4-quinoldione and novel reaction derivatives

One- and two-dimensional NMR experiments were used for the unambiguous assignment of the 1H and 13C NMR chemical shifts of 3,3-diisopentenyl-N-methyl-2,4-quinoldione and five novel reaction derivatives.

Attenuation of ischemia/reperfusion-induced intestinal injury by oleo-resin from Copaifera langsdorffii in rats

Copaifera langsdorffii oleo-resin (CLOR) is a reputed herbal medicine used to combat gastrointestinal functional disorders. Our previous studies show that CLOR prevents gastric ulceration and promotes wound healing. This study examined the effects of CLOR on intestinal damage associated with mesenteric ischemia/reperfusion in rat. Wistar albino rats were divided into four groups of six in each. Group 1: Sham operated, Group 2: Vehicle + 45 min of ischemia followed by 60 min reperfusion (I/R), Groups 3 and 4: I/R + CLOR (200 and 400 mg /kg, p.o., respectively). All treatments were given 24 h, 12 h and 2 h before I/R. Animals were sacrificed at the end of reperfusion period and ileal tissue samples were obtained for biochemical analysis. Myeloperoxidase (MPO), an index of polymorphonuclear leukocytes; malondialdehyde (MDA), an end product of lipoperoxidation; catalase (CAT), an antioxidant enzyme; reduced glutathione (GSH), a key antioxidant; and nitrite, a marker of nitric oxide (NO) production were determined in ileum homogenates. The results show that I/R produces a significant increase in MDA content, MPO, and CAT activities with a significant decrease in GSH and an elevation in nitrite production, as compared to sham control. CLOR treatment caused significant attenuations in I/R-associated increases of MPO, MDA and CAT activities and on nitrite level. Besides, CLOR could effectively prevent the I/R-associated depletion of GSH. The data indicate that the oleo-resin has a protective action against I/R-induced intestinal tissue damage, which appeared to be, at least in part, due to an antioxidant and anti-lipid peroxidation mechanism.

Protective effect of Copaifera langsdorffii oleo-resin against acetic acid-induced colitis in rats

The oleo-resin from Copaifera langsdorffii (Leguminosae) was evaluated in rats on acetic acid-induced colitis. Rats were pretreated orally (15 and 2 h) or rectally (2 h) before the induction of colitis with copaiba oleo-resin (200 and 400 mg/kg) or vehicle (1 ml, 2% Tween 80). Colitis was induced by intracolonic instillation of a 2 ml of 4% (v/v) acetic acid solution and 24 h later, the colonic mucosal damage was analyzed for the severity of macroscopic colonic damage, myeloperoxidase (MPO) activity, and malondialdehyde levels. A significant reduction in gross damage score and in wet weight/length ratio of colonic tissue were evident in test substance-pretreated animals as compared to vehicle or oleo-resin alone-treated controls. This effect was confirmed biochemically by a reduction in colonic myeloperoxidase activity, the marker of neutrophilic infiltration, and by a marked decrease in malondialdehyde level, an indicator of lipoperoxidation. Furthermore, microscopical examination revealed the diminution of inflammatory cell infiltration, and submucosal edema in the colon segments of rats treated with copaiba oleo-resin. The data indicate the protective effect of copaiba oleo-resin in the animal model of acute colitis possibly through an antioxidant and or anti-lipoperoxidative mechanism.

Ternatin, an anti-inflammatory flavonoid, inhibits thioglycolate-elicited rat peritoneal neutrophil accumulation and LPS-activated nitric oxide production in murine macrophages

Ternatin, an anti-inflammatory flavonoid from Egletes viscosa Less., was examined for its possible influence on thioglycolate-elicited neutrophil influx into the rat peritoneal cavity in vivo and nitric oxide production in lipopolysaccharide (LPS)-activated mouse peritoneal macrophages ex vivo. The neutrophil influx induced by thioglycolate was found to be significantly lower in ternatin (25 and 50 mg/kg, s. c.) pre-treated rats with a similar magnitude of inhibition produced by dexamethasone (1 mg/kg, s. c.), a known anti-inflammatory agent. Also, peritoneal macrophages from ternatin (25 mg/kg)-treated mice that were exposed to LPS demonstrated significantly less production of nitric oxide (NO). These results suggest that ternatin exerts its anti-inflammatory action, at least in part, through inhibition of neutrophil migration and modulation of macrophage function.

Brain abscess caused by Cladophialophora (Xylohypha) bantiana in a renal transplant patient

Infectious disease is the most significant cause of morbidity and mortality in allotransplantation because of heavy immunosuppression. Brain abscesses caused by melanized fungi have been found occasionally and are an example of this complication. In this paper, we describe a case in a 61-year-old black man, who received a cadaveric kidney transplantation in December 1993, followed by triple therapy with cyclosporine, azathioprine, and prednisone. The patient developed right hemiparesis at the beginning of April 1998. A computed tomography scan showed a mass in the left parieto-temporal region of the brain. The patient underwent surgery and a brown-colored encapsulated brain abscess was resected. Histology of the tissue revealed a large number of pigmented fungal hyphae. Culture in a Sabouraud dextrose medium with cyclohexamide and chloramphenicol at 25 degrees C resulted in the growth of dark-green colonies. The fungus identified was Cladophialophora bantiana, based on characteristic microscopic features and on growth at 40 degrees C. The abscess recurred in spite of treatment with fluconazole. The patient was submitted to a second brain surgical procedure and was treated with amphotericin B in addition to fluconazole. Ten days later the patient's blood cultures became positive for Escherichia coli. After 3 days the patient died due to septic shock.

Anti-inflammatory and smooth muscle relaxant activities of the hydroalcoholic extract and chemical constituents from Amburana cearensis A C Smith

Amburana cearensis A. C. Smith, Fagaceae, is a medicinal plant commonly known as 'cumaru' and used in Northeast Brazil for the treatment of respiratory tract diseases. In the present work, we investigated the anti-inflammatory and smooth muscle relaxant activities of the hydroalcoholic extract (HAE), coumarin (Coum) and fl avonoid fraction (FF) isolated from the trunk barks of Amburana cearensis A. C. Smith. It was shown that HAE (200 and 400 mg/kg), Coum (20 and 40 mg/kg) and FF (40 mg/kg), administered orally, significantly inhibited both leukocyte and neutrophil migrations, in the carrageenan or N-formyl-methyl-leucyl-phenylalanine (fMLP)-induced migration in rat peritoneal cavity. The increase in cutaneous vascular permeability induced by serotonin in rats was significantly blocked by HAE (150 mg/kg, i.p.), Coum (5 mg/kg, i.p.) and FF (20 mg/kg, i.p.). However, only HAE blocked the histamine effect on Evans blue extravasation. In the guinea-pig trachea precontracted with carbachol (0.3 microM), histamine (0.1 microM) or KCl (0.1 M), the HAE, Coum and FF evoked a concentration-dependent relaxation in the presence of the three agonists. HAE (100-800 microg/ml) and Coum (4-32 microg/ml) also caused significant relaxation of the rat vas deferens previously contracted with adrenaline, acetylcholine or barium chloride. In addition, HAE, Coum and FF inhibited the histamine and serotonin-induced increase of cutaneous vascular permeability in rats.

Smooth muscle relaxant effect of kaurenoic acid, a diterpene from Copaifera langsdorffii on rat uterus in vitro

The effect of kaurenoic acid, a diterpene isolated from the oleo-resin of the popular medicinal plant Copaifera langsdorffii (Leguminaceae), was analysed on rat uterine muscle responsiveness to various drugs in vitro. Cumulative concentration-response curves to acetylcholine and oxytocin were obtained before and after incubation of uterine segments with up to 160 microm of kaurenoic acid. The maximal contractile response (E(max)) evoked by these agonists was inhibited by kaurenoic acid in a concentration-related manner; at 160 microm, kaurenoic acid depressed the E(max) of oxytocin and acetylcholine by 83% and 91%, respectively. The relaxation caused by kaurenoic acid on oxytocin-induced contraction was unaffected in the presence of tetraethyl ammonium, a compound that blocks the calcium activated potassium channels. It was partially reversed by glibenclamide (10(-5) m), an ATP-sensitive potassium channel blocker. Also, kaurenoic acid at 160 microm concentration was found to inhibit significantly the CaCl(2)-evoked contractile responses in a medium of high potassium and zero calcium. Furthermore, kaurenoic acid was found to relax the sustained tonic contraction induced by acetylcholine, oxytocin, BaCl(2) and KCl in a concentration-dependent way. However, KCl-induced tonic contraction was only weakly inhibited by kaurenoic acid. These data indicate that the diterpene, kaurenoic acid, exerts a uterine relaxant effect acting principally through calcium blockade and in part, by the opening of ATP-sensitive potassium channels.

Anti-inflammatory effect of kaurenoic acid, a diterpene from Copaifera langsdorffii on acetic acid-induced colitis in rats

Kaurenoic acid, a diterpene from Copaifera langsdorffii (Leguminaceae), was evaluated on rat colitis induced by acetic acid. Rats were pretreated orally (15 and 2 h before) or rectally 2 h before induction of colitis with kaurenoic acid (50 and 100 mg/kg) or vehicle (1 ml, 3% DMSO). Colitis was induced by intracolonic instillation of a 2 ml of 4% (v/v) acetic acid solution and, 24 h later, the colonic mucosal damage was analysed macroscopically for the severity of mucosal damage, the myeloperoxidase (MPO) activity and the malondialdehyde (MDA) levels in the colon segments. A marked reduction in gross damage score (52% and 42%) and wet weight of damaged colon tissue (39% and 32%) were observed in rats that received 100 mg/kg kaurenoic acid, respectively, by rectal and oral routes. This effect was confirmed biochemically by a two- to three-fold reduction of colitis associated increase in MPO activity, the marker of neutrophilic infiltration and by a marked decrease in MDA level, an indicator of lipoperoxidation in colon tissue. Furthermore, light microscopy revealed the marked diminution of inflammatory cell infiltration and submucosal edema formation in the colon segments of rats treated with the test compound. These findings indicate the anti-inflammatory potential of kaurenoic acid in acetic acid-induced colitis.

Investigation on the wound healing activity of oleo-resin from Copaifera langsdorffi in rats

The wound healing activity of oleo-resin from Copaifera langsdorffii Desf. (Leguminaceae) bark was evaluated in rats on experimental wounds. The oleo-resin was tested by monitoring wound contraction in excised wounds and by measuring tensile strength in healing incision wounds. The topical application of oleo-resin at a concentration of 4% accelerated wound contraction in open wounds. The mean values of wound contraction in oleo-resin treated rats on day 9 was 84.05% +/- 2.37% as against 51.29% +/- 9.54% seen in controls and the difference was statistically significant (p < 0.05). No significant differences in the rates of wound contraction were observed on days 12, 15, 18 and 21. Also, the tensile strength in healing incised wounds was found to be significantly higher in the group of animals treated with 4% oleo-resin on day 5 but not on days 7 and 12 (controls: 35.95 +/- 7.44 g/cm; oleo-resin: 71.48 +/- 5.77 g/cm; p < 0.05). These results indicate the beneficial effect of C. langsdorffii oleo-resin on wound healing and justify its traditional use for the treatment of wounds.

Antinociceptive and gastroprotective effects of diterpenes from the flower buds of Egletes viscosa

Centipedic acid and 12-acetoxy-hawtriwaic acid lactone, diterpenes isolated from the flower buds of Egletes viscosa (Asteraceae) were assayed for antinociceptive and gastroprotective activities in animal models of nociception and gastric ulcer. In the chemical nociception induced in mice by intraperitoneal acetic acid and subplantar formalin injections, both diterpenes (25 and 50 mg/kg, p. o.) exerted potent antinociception in a manner similar to indomethacin (5 mg/kg, p. o.). In the formalin test, only the late phase nociceptive response (20 - 25 min) and not the early phase response (0 - 5 min) was inhibited by these diterpenes. However, these compounds were found to be ineffective against thermal nociception in the hot-plate test. Further, the diterpenes reduced the severity of absolute ethanol-induced gastric lesions in rats. At the dose of 50 mg/kg, both centipedic acid and 12-acetoxy hawtriwaic acid suppressed the gastric lesions by 53 % and 63 %, respectively. Against the gastric ulceration induced by indomethacin, only centipedic acid (25 and 50 mg/kg) showed significant inhibition by about 47 - 49 %. The data suggested the gastroprotective and peripheral analgesic properties of diterpenes isolated from E. viscosa.

The cytotoxic and embryotoxic effects of kaurenoic acid, a diterpene isolated from Copaifera langsdorffii oleo-resin

In this work, we studied the effects of kaurenoic acid, a diterpene isolated from the oleo-resin of Copaifera langsdorffii in developing sea urchin (Lytechinus variegatus) embryos, on tumor cell growth in microculture tetrazolium (MTT) test and on mouse and human erythrocytes in hemolysis assay. Continuous exposure of embryos to kaurenoic acid starting immediately after fertilization inhibited the first cleavage (IC(50): 84.2 microM) and progressively induced embryo destruction (IC(50): 44.7 microM and < 10 microM for blastulae and larvae stages, respectively). In MTT assay, kaurenoic acid at a concentration of 78 microM produced growth inhibition of CEM leukemic cells by 95%, MCF-7 breast and HCT-8 colon cancer cells by 45% each. Further, kaurenoic acid induced a dose-dependent hemolysis of mouse and human erythrocytes with an EC(50) of 74.0 and 56.4 microM, respectively. The destruction of sea urchin embryos, the inhibition of tumor cell growth and the hemolysis of mouse and human erythrocytes indicate the potential cytotoxicity of kaurenoic acid.

Organic carbonate from Calotropis procera leaves

The leaves of Calotropis procera yielded an organic carbonate (1), along with stigmasterol and beta-sitosterol, identified by spectroscopic methods.

Vitamin A and all-trans and 9-cis retinoic acids inhibit cell proliferation during the progression phase of hepatocarcinogenesis in Wistar rats

The effects of vitamin A and all-trans and 9-cis retinoic acids on the progression phase of hepatocarcinogenesis were evaluated in this study. For this purpose, male Wistar rats were first submitted to the resistant hepatocyte model of carcinogenesis (diethylnitrosamine for initiation and 2-acetylaminofluorene for selection/promotion). Ten months after initiation, the animals were distributed into four groups and treated by gavage, every other day and during eight weeks, with corn oil (control group), vitamin A (10 mg/kg of body wt), all-trans retinoic acid (10 mg/kg body wt), or 9-cis retinoic acid (10 mg/kg body wt). After this period, the animals were killed one hour after intraperitoneal administration of 5-bromo-2-deoxyuridine (BrdU, 100 mg/kg body wt). At the time of sacrifice, liver samples were collected for histopathological (hematoxylin-eosin) examination and immunohistochemical detection of glutathione S-transferase and BrdU, as well as for analysis of retinol and retinoic acid concentrations. Histopathological examination showed the lowest incidence of hepatocarcinomas in vitamin A-treated animals. Moreover, groups treated with retinoids demonstrated lower hepatic BrdU labeling indexes in the neoplastic lesions, as well as in their respective surrounding tissues, than controls. Thus vitamin A and all-trans and 9-cis retinoic acid strongly inhibited cell proliferation when administered during the progression phase of hepatocarcinogenesis. Therefore, the anticarcinogenic effects that have been attributed to these retinoids could be partially related to their capacity of inhibiting in vivo cell proliferation.

Pentaoxygenated xanthones and fatty acids from Bredemeyera brevifolia

The polar portion of an ethanol extract of Bredemeyera brevifolia yielded two pentaoxygenated xanthones whose structures were determined as 1-methoxy-2,3,7,8-dimethylenedioxyxanthone, and 1,7,8-trimethoxy-2,3-methylene-dioxyxanthone. The apolar fraction contained various known fatty acids, structure determinations were accomplished by spectral analysis, mainly NMR, chemical derivatization and comparison to literature values.

Antiproliferative effects of compounds derived from plants of Northeast Brazil

Ten compounds derived from plants indigenous to Northeast Brazil were examined for antiproliferative effects on human cells in vitro. The effects of these phytochemicals on cell growth were determined by the MTT microtitre assay with 3-day continuous drug exposure. Three human cell lines were used: CEM leukaemia, SW1573 lung tumour and CCD922 normal skin fibroblasts. Four active compounds were found with IC(50) values less than 10 microg/mL in the two cancer cell lines. Oncocalyxones A and C, both 1,4-anthracenediones from Auxemma oncocalyx (Boraginaceae), showed cytotoxicity with mean IC(50) values of 0.8-2, 7-8 and 12-13 microg/mL against CEM, SW1573 and CCD922, respectively. One diterpene and one flavonoid, both from Egletes viscosa (Compositae), were also active. 12-Acetoxy-hawtriwaic acid lactone was cytotoxic with mean IC(50) values of 6, 10 and 10 microg/mL, respectively. 4,5-Dihydroxy-3,3,7, 8-tetramethoxy flavone (ternatin) was only growth-inhibitory with mean IC(50) values of 2, 1 and 10 microg/mL, respectively. These four most active compounds were examined further for their effects on DNA integrity and on DNA synthesis. All but ternatin caused substantial DNA damage and marked inhibition of 5-bromo-2'-deoxyuridine incorporation within 24 h. This study demonstrated the antiproliferative activity of four novel phytochemicals, three of which are DNA-reactive and inhibit DNA synthesis. Further studies are warranted to evaluate these compounds for antitumour potential.

Social determinants of psychiatric morbidity and well-being in immigrant elders and whites in east London

OBJECTIVES

The social conditions under which migrants to the UK live may be more significant than the experience of migration itself in leading to increased risk of mental illness. We aimed to compare the prevalence of mental, physical and social health problems in elderly Somalis, Bengalis and whites living in a deprived inner London area and examine associations between environmental circumstances, social support, physical health status, mood and life satisfaction in these groups. In addition, we wanted to test the hypothesis that differences in mental health between immigrants and whites are explained by social disadvantages rather than ethnicity.

DESIGN

Cross-sectional survey with participants drawn from age-sex registers of general practices, augmented by other sources.

SETTING

East London--'first-generation' Somali and Bengali immigrants and white British.

SUBJECTS

A total of 274 people aged 60+ years: 72 Somalis, 75 Bengalis and 127 whites.

MAIN OUTCOME MEASURES

Symptoms of Anxiety and Depression Scale (SAD), Life Satisfaction Index (LSI). High SAD scores indicate more anxiety and depression symptoms; high LSI scores indicate greater life satisfaction.

MAIN RESULTS

Highest SAD scores were found among Bengalis; lowest LSI scores were found among Bengalis and Somalis. The prevalences of depression (SAD score 6+) were 25% in Somalis, 77% in Bengalis and 25% in east London whites. Physical health status and SAD scores were associated in Somalis (r = +0.31, p < or = 0.01). Bengalis (r = +0.47, p < or = 0.001) and east London whites (r = +0.27, p < or = 0.01). Physical health problems also related to lower LSI scores in Somalis (r = -0.24, p < or = 0.05) and east London whites (r = -0.24, p < or = 0.01). Social factors (i.e. poor housing conditions, low family support and reported need of community services) were strongly associated with SAD scores among Somalis (r = +0.5, p < or = 0.001) and, to a lesser extent, among Bengalis (r = +0.33, p < or = 0.01). Ethnicity (i.e. being an immigrant as opposed to a non-immigrant) became a statistically non-significant risk factor for high SAD scores after adjusting for the effects of age, weekly income, physical health and social problems (OR = 0.71, 95% CI = 0.5-1.1, p = 0.09). A residual, but much attenuated effect for ethnicity on LSI scores persisted in the estimated model after controlling for the same set of independent risk factors (OR = 0.7, 95% CI = 0.4-1, p = 0.05).

CONCLUSION

The marked variation in mental health between ethnic groups in east London might be a reflection of socioeconomic and health differentials acting concomitantly and adversely. Inequalities in housing, social support, income and physical health status accounted for variation in mood observed between immigrants and whites, and may partly explain differences in life satisfaction. These results seem to support a 'multiple jeopardy' theory of ageing in ethnic minorities in east London. Greater efforts are needed to recognize anxiety and depression in immigrant elders. Better social support and housing among 'minority ethnic' elders who live alone might be expected to alleviate social stress and improve mental health and psychological well-being.

Gastroprotective effect of Copaifera langsdorffii oleo-resin on experimental gastric ulcer models in rats

The effects of oleo-resin obtained from the stem bark of Copaifera langsdorffii on ethanol, indomethacin and hypothermic restraint-stress induced gastric lesions were studied in rats. Oral administration of oleo-resin at doses of 200 and 400 mg/kg provided dose-dependent significant protection against gastric damage caused by ethanol and restraint stress, and at a dose of 400 mg/kg it also prevented the gastric ulceration induced by indomethacin. Further, in the 4 h pylorus ligated rats, the accumulation of gastric juice volume and the mucus secretion was significantly enhanced by oleo-resin whereas the total acidity was inhibited. These results highlight the gastroprotective potential of C. langsdorffii oleo-resin and the need for a systematic study on this traditional remedy.

Hypoglycemic effect of trans-dehydrocrotonin, a nor-clerodane diterpene from Croton cajucara

trans-Dehydrocrotonin (t-DCTN), a 19-nor-clerodane diterpene isolated from the bark of Croton cajucara Benth. (Euphorbiaceae) demonstrated a significant hypoglycemic activity in alloxan-induced diabetic rats but not in normal rats, at oral doses of 25 and 50 mg/kg body weight. The drug also effectively lowered the blood sugar levels in glucose fed normal rats. The hypoglycemic effect of t-DCTN was almost comparable to that produced by glibenclamide (2 mg/kg), a clinically useful drug. The results indicate the antihyperglycemic potential of t-DCTN.

The leaf essential oil of Psidium guyanensis offers protection against pentylenetetrazole-induced seizures

The essential oil obtained from the leaves of Psidium guyanensis Pers. (Myrtaceae) was studied against lethal seizures induced by intraperitoneal injection of pentylenetetrazole (80 mg/kg), picroptoxin (6 mg/kg), and strychnine (2 mg/kg) in mice. At oral doses of 100, 200, and 400 mg/kg, the essential oil attenuated the severity of pentylenetetrazole-induced seizures and offered a dose-related protection but it was found to be ineffective against convulsions induced by picrotoxin and strychnine. The blockade of its protective effect on pentylenetetrazole lethal seizures by caffeine (10 and 50 mg/kg, i.p.) suggests a probable participation of endogenous adenosine in its mechanism. Furthermore, a peripheral mechanism also appears to be involved as the essential oil (5-20 micrograms/ml) was able to block selectively the acetylcholine (1.65 x 10(-6) M) induced contractions but not those evoked by high potassium (80 mM) or caffeine (2 x 10(-3) M) on isolated toad rectus abdominis muscle.

Investigations on the gastroprotective and antidiarrhoeal properties of ternatin, a tetramethoxyflavone from Egletes viscosa

The study was designed to verify the gastroprotective and antidiarrhoeal effects of ternatin, tetramethoxyflavone isolated from Egletes viscosa Less. The gastroprotective function of ternatin was evaluated in rats against gastric mucosal damage induced by hypothermic restraint stress, absolute ethanol, and indomethacin, whereas the antidiarrhoeal activity was investigated by studying its influence on gastrointestinal transit as measured by a charcoal marker and on castor oil-induced accumulation of intestinal fluid in mice and also on contractile responses evoked by acetylcholine, histamine, serotonin, and barium chloride in isolated guinea-pig ileum. The results demonstrate that pretreatment of animals with the plant flavonoid (25 and 50 mg/kg, i.p.) produces a significant inhibition of gastric lesions induced by ethanol but not those induced by restraint stress or indomethacin and suggest a probable involvement of a prostaglandins-independent mechanism of gastroprotection. At similar doses, both the intestinal transit as well as the accumulation of intestinal fluids induced by castor oil in mice were significantly inhibited by ternatin. Furthermore, the flavonoid antagonised the contractile responses evoked by different agonists on guinea-pig ileum in vitro and its inhibitory potential for the drugs are in the order of acetylcholine > histamine > serotonin > barium chloride. Taken together, these results point out a possible antidiarrhoeal effect of ternatin since inhibition of intestinal motility and secretion can greatly control clinical diarrhoea.

Biologically active flavonoids and terpenoids from Egletes viscosa

The steam volatile components from the hexane extract of dried flower buds of Egletes viscosa were identified by gas chromatography-mass spectrometry as trans-carvyl acetate, cis-carvyl acetate, sabinyl acetate, verbenyl acetate, cyclopentaethylidene, geranyl acetate and 5-methylfuranone, and trans-pinocarvyl acetate (major component). From the non-volatile residue, centipedic acid and a novel clerodane diterpene, 12-acetoxy-hawtriwaic acid lactone, were isolated. From the ethanol extract, ternatin (4',5-dihidroxy-3,3',7,8-tetramethoxyflavone), was isolated. Ternatin showed anti-inflammatory, hepatoprotection and gastroprotection properties, and, according to the NCI protocols, it showed moderate activity against HIV. The diterpenes showed antispasmodic activity. Structure determination of these secondary metabolites was accomplished by spectrometric methods, including 2D NMR, chemical interconversion and X-ray crystallographic analysis.

Protective effect of ternatin, a flavonoid isolated from Egletes viscosa less., in experimental liver injury

The effect of ternatin, a tetramethoxyflavone from Egletes viscosa Less., on liver injury induced by carbon tetrachloride (CCl4) was investigated in rats. Twenty-four hours following CCl4 insult (2.5 ml/kg s.c.), changes in the serum enzymes, alanine aminotransferase, aspartate aminotransferase and gamma-glutamyltransferase, as well as liver cell histology were used as indices of hepatic dysfunction. The results show that ternatin (30 mg/kg i.p. daily for 5 consecutive days) causes marked inhibition of CCl4-induced serum enzymes and morbid histologic changes. The observation suggests that ternatin possesses antihepatotoxic activity.