Inhibitory efficacy of various antibiotics on matrix and viable mass of Staphylococcus aureus and Pseudomonas aeruginosa biofilms.

Both bacteria and the matrix are essential for the development of biofilms. Antimicrobials should therefore be tested against both components. The aim of this study was to determine the structure-activity relationships of different antibiotics against biofilm-forming Staphylococcus aureus and Pseudomonas aeruginosa strains using in vitro biofilm discriminatory assays.

Screening of some Tanzanian medicinal plants from Bunda district for antibacterial, antifungal and antiviral activities.

Extracts from 50 plant parts obtained from 39 different plants belonging to 22 families used to treat infectious diseases in Bunda district, Tanzania, were screened against twelve microorganisms, including the bacteria Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Salmonella typhimurium, the fungi Aspergillus niger, Candida albicans, and the viruses Herpes Simplex Virus type 1, Vesicular Stomatitis Virus T2, Coxsackie B2 and Semliki Forest A7. The highest activity was obtained for the n-hexane extract of Elaeodendron schlechteranum root bark against the Gram-positive bacteria Bacillus cereus (MIC 0.97 microg/ml and MBC 1.

Choline-stabilized orthosilicic acid supplementation as an adjunct to calcium/vitamin D3 stimulates markers of bone formation in osteopenic females: a randomized, placebo-controlled trial.

Background: Mounting evidence supports a physiological role for silicon (Si) as orthosilicic acid (OSA, Si(OH)4) in bone formation. The effect of oral choline-stabilized orthosilicic acid (ch-OSA) on markers of bone turnover and bone mineral density (BMD) was investigated in a double-blind placebo-controlled trial.

Methods: Over 12-months, 136 women out of 184 randomized (T-score spine < -1.

Isokinetic scapular muscle performance in young elite gymnasts.

Context: During gymnastic exercises, considerable force output is required in the shoulder girdle muscles. Isokinetic performance of the scapular muscles in young, elite gymnasts has not been examined.

Objective: To compare the isokinetic muscle performance of the scapular muscles between elite adolescent gymnasts and nonathletic adolescents to identify differences in strength, endurance, and muscle balance based on high-level sport participation.

Ethnobotanical survey and antibacterial activity of some plants used in Guinean traditional medicine.

A total of 418 healers have been interviewed in Guinea, a coastal country of West Africa, ranging between 7 degrees 30 and 12 degrees 30 of northern latitude and 8 degrees and 15 degrees of western longitude. Plant species used by the local inhabitants to treat infectious diseases were identified using ethnobotanical, ethnographic and taxonomic methods. During these investigations, 218 plants were registered, of which the following were the most frequently used: Erythrina senegalensis, Bridelia ferruginea, Crossopteryx febrifuga, Ximenia americana, Annona senegalensis, Cochlospermum tinctorium, Cochlospermum planchonii, Lantana camara, Costus afer, Psidium guajava, Terminalia glaucescens, Uapaca somon and Swartzia madagascariensis.

A novel isoflavonoid from Millettia puguensis.

From the roots of Millettia puguensis (Leguminosae), a novel isoflavonoid (5), 2'-methoxy-4',5'-methylenedioxy-7,8-[2-(1-methylethenyl)furo]isoflavone, and four known compounds, i. e., lupeol (1), (-)-maackiain (2), 6,7-dimethoxy-3',4'-methylenedioxyisoflavone (3) and 7,2'-dimethoxy-4',5'-methylenedioxyisoflavone (4) were isolated and identified by 1H-, 13C-NMR and mass spectroscopy.

Anti-infective potential of natural products: how to develop a stronger in vitro 'proof-of-concept'.

Natural products, either as pure compounds or as standardized plant extracts, provide unlimited opportunities for new drug leads because of the unmatched availability of chemical diversity. To secure this, a number of pivotal quality standards need to be set at the level of extract processing and primary evaluation in pharmacological screening models. This review provides a number of recommendations that will help to define a more sound 'proof-of-concept' for antibacterial, antifungal, antiviral and antiparasitic potential in natural products.

Method development and validation for monitoring in vivo oxidative stress: evaluation of lipid peroxidation and fat-soluble vitamin status by HPLC in rat plasma.

Monitoring in vivo oxidative stress implicates the evaluation of damage and defence parameters by well-established, validated methods. We report two optimized and validated HPLC methods for measurement of malondialdehyde (MDA) and fat-soluble vitamins in rat plasma. For the MDA method, optimization experiments of the thiobarbituric acid test resulted in the addition of 1% butylhydroxytoluene to the reaction mixture and in a heating time reduction to 40 min, ensuring inhibition of further lipid peroxidation during the test.

Proanthocyanidins in health care: current and new trends.

Polyphenolic compounds are widely distributed in higher plants and are an integral part of the human diet. Recent interest in these substances has been stimulated by their potential health benefits, which are believed to arise mainly from their antioxidant activity. In the past years, the antioxidant activity of flavonoids has been studied in detail.

Anticomplement and antioxidant activities of new acetylated flavonoid glycosides from Centaurium spicatum.

In addition to the three acetylated flavonol glycosides, quercetin 3- O-[(2,3,4-triacetyl-alpha-rhamnopyranosyl)-(1-->6)]-beta-galactopyranoside, quercetin 3- O-[(2,3,4-triacetyl-alpha-rhamnopyranosyl)-(1-->6)]-3-acetyl-beta-galactopyranoside, and quercetin 3- O-[(2,3,4- triacetyl-alpha-rhamnopyranosyl)-(1-->6)]-4-acetyl-beta-galactopyranoside, which have recently been isolated from Centaurium spicatum (L.) Fritsch (Gentianaceae), a new pentaacetylated flavonoid glycoside was isolated from the same plant. Structure elucidation, especially the localization of the acetyl groups, and complete (1)H- and (13)C-NMR assignments, was carried out using one- and two-dimensional NMR methods, including (1)H- and (13)C-NMR, DEPT-135 and DEPT-90, and gradient-assisted experiments such as DQF-COSY, TOCSY, HSQC and HMBC.

Characterisation of new oligoglycosidic compounds in two Chinese medicinal herbs.

A series of caffeic acid derivatives (3,5-dicaffeoyl-quinic acid, 3,4-dicaffeoyl-quinic acid, and 4,5-dicaffeoyl-quinic acid), and the new compound beta,3,4-trihydroxyphenethyl-O-[beta-apiofuranosyl-(1-->4)-alpha- rhamnopyranosyl-(1-->3)]-(4-O-caffeoyl)-beta-glucopyranoside (wedelosin), as well as three known flavonoid glycosides (quercetin 3-O-beta-glucoside, kaempferol 3-O-beta-apiosyl-(1-2)-beta-glucoside, and astragalin or kaempferol 3-O-beta-glucoside) were isolated from the Chinese medicinal herb Wedelia chinensis. Wedelosin showed an inhibitory activity on both the classical and the alternative activation pathway of the complement system. Another Chinese medicinal herb, Kyllinga brevifolia, yielded two known flavonoid glycosides [kaempferol 3-O-beta-apiosyl-(1-2)-beta-glucoside and isorhamnetin 3-O-beta-apiosyl-(1-2)-beta-glucoside], and a new quercetin triglycoside [quercetin 3-O-beta-apiofuranosyl-(1-->2)-beta-glucopyranoside 7-O-alpha-rhamnopyranoside].

Chemical and biological investigations on Zizyphus spina-christi L.

Different extracts and fractions of the leaves, fruits and seeds of Zizyphus spina-christi L. grown in Egypt were investigated in vitro for their antiviral, antifungal and antibacterial activities. The flavonoids quercetin, hyperoside, rutin and quercetin-3-O-[beta-xylosyl-(1-2)-alpha-rhamnoside] 4'-O-alpha- rhamnoside) were isolated.

Synthesis and evaluation of caffeic acid amides as antioxidants.

A series of amides of caffeic acid has been synthesised and their antioxidant properties evaluated as lipid peroxidation inhibitors. Anilides of caffeic acid were found to be very efficient antioxidants with IC50's of 0.3 microM.

Antibacterial and antifungal activities of neocryptolepine, biscryptolepine and cryptoquindoline, alkaloids isolated from Cryptolepis sanguinolenta.

From the 80% EtOH extract of Cryptolepis sanguinolenta (Lindl.) Schlechter (Periplocaeae) root bark, a cryptolepine isomer named neocryptolepine, and two dimeric alkaloids named biscryptolepine and cryptoquindoline were isolated. These compounds were tested for their putative antibacterial and antifungal activities.

Tympanic membrane changes in experimental purulent otitis media.

The stiffness properties of the gerbil tympanic membrane (TM) were investigated during the early course of experimental purulent otitis media produced by middle ear inoculation (n = 49) with type 3 Streptococcus pneumoniae. In a first approach the acoustic admittance and susceptance were measured in vitro with tympanometry and in a second approach the tympanic membrane displacement in response to static pressure was measured with moire interferometry. A histological assessment of the tympanic membrane was made concurrently.

In vitro biological activities of alkaloids from Cryptolepis sanguinolenta.

In our biological screening of higher plants, an aqueous and an 80% EtOH extract from the root bark of Cryptolepis sanguinolenta showed potent antibacterial, anticomplementary, and moderate antiviral activities, but no antifungal effect could be detected. Bioassay-guided fractionation of the 80% EtOH extract led to the isolation of three alkaloids: quindoline (1), hydroxycryptolepine (2), cryptolepine.HCl (3), and the corresponding base cryptolepine (4).

Triterpenoid saponins from Maesa lanceolata.

Six new homologous triterpenoid saponins were isolated from the methanol extract of the leaves of Maesa lanceolata and characterized as 3 beta-O-[alpha-L-rhamnopyranosyl(1 --> 2)-beta-D-galactopyranosyl (1 --> 3)]-[beta-D-galactopyranosyl(1 --> 2)]-beta-D-glucuronopyranosides alpha-diol, 22 alpha-angeloyloxy-16 alpha-butanoyloxy-13 beta,28-oxydoolean-21 beta,28 alpha-diol, 16 alpha,22 alpha-diangeloyloxy-13 beta,28-oxydoolean-21 beta,-28 alpha-diol, 22 alpha-angeloyloxy-13 beta,28-oxydo-16 alpha-(2-methyl-butanoyloxy)-olean-21 beta,28 alpha-diol, 21 beta-acetoxy-22 alpha-angeloyloxy-13 beta,28-oxydo-16 alpha-propanoyloxyolean-28 alpha-ol, 21 beta-acetoxy-22 alpha-angeloyloxy-16 alpha-butanoyloxy-13 beta,28-oxydoolean-28 alpha-01. The structures were established on the basis of chemical and spectral evidence.

Effect of temperature on in vitro proliferative activity of human umbilical vein endothelial cells.

Human umbilical vein endothelial cells, skin fibroblasts, and retinal pigment epithelial cells are cultivated in medium supplemented with 15 to 20% serum in our laboratory. The effects of various incubation temperatures on the proliferation of these cells was examined. Our study shows that the mitogenic response of the endothelial cells to a change of temperature differed markedly from that of the fibroblasts and epithelial cells.

Locking graft in the treatment of tibial pseudarthrosis.

Despite modern treatments of tibial fractures, we still have nonunions. In case of failure we used a method of treatment which has become less popular over the last decades. A rectangular inlay graft is harvested from the anteromedial tibial surface.

Structure and chemotherapeutical activity of a polyisoprenylated benzophenone from the stem bark of Garcinia huillensis.

The stem bark of Garcinia huillensis grown in Zaïre and used in central-African traditional medicine has been subjected to a bioassay-guided fractionation. The chemotherapeutically active petroleum ether extract afforded fatty acids, aliphatic alcohols, triterpenes and a polyisoprenylated benzophenone, which was identified as garcinol, also named camboginol. This compound has been shown to exhibit chemotherapeutical activity gram-positive and gram-negative cocci, mycobacteria and fungi.

Plant Antiviral Agents; VI.1 3-Methoxyflavones as Potent Inhibitors of Viral-Induced Block of Cell Synthesis.

An investigation of the constituents responsible for the pronounced antiviral activity observed for extracts of EUPHORBIA GRANTII Oliv. stems has afforded four related 3-methoxyflavones exhibiting remarkable activities against picornaviruses and vesicular stomatitis virus. All compounds were found to be derivatives of 3-methylquercetin.