Identification of harman as the antibiotic compound produced by a tunicate-associated bacterium

The alkaloid harman, previously reported from some marine invertebrates, was identified as the antibiotic substance of the tunicate-associated bacterium Enterococcus faecium. It exhibited antibacterial activity (MIC, 0.017 mM) against the ichthyopathogenic strain Vibrio anguillarum.

New ketosteroids from the red alga Hypnea musciformis

The dichloromethane/methanol extract from the red alga Hypnea musciformis exhibited PPE elastase inhibition. A diketosteroid, the 20-hydroxy-5alpha-cholest-22-ene-3,6-dione was responsible for this activity. Two new steroids were isolated, 2 was assigned as the 6alpha-hydroxy-cholest-4-ene-3-one and 3 as the 6alpha-hydroxy-cholest-4,22-diene-3-one. The structures were assigned mainly on the basis of 1H and 13C NMR experiments.

Total synthesis and determination of the absolute configuration of coscinosulfate. A new selective inhibitor of Cdc25 protein phosphatase

The first total synthesis of coscinosulfate 1, a metabolite isolated from a sea sponge, starting from (+)-sclareolide 3 is described. The convergent synthesis strategy relies on the coupling of sulfone 21 with the bromide 26. The sulfone fragment 21 was obtained by successive asymmetric aldol reaction with aldehyde 2 to introduce the stereocenters at C-12 and C-13, followed by one-carbon homologation via Horner-Wadsworth-Emmons olefination. The selective sulfatation at C-12 was accomplished through the quinone intermediate 31 obtained by selective oxidation of hydroquinone 30; this, when followed by reduction, furnished the desired coscinosulfate 1. X-ray analysis of the intermediate aldehyde 18 confirmed the proposed structure.

Coscinosulfate, a CDC25 phosphatase inhibitor from the sponge Coscinoderma mathewsi

The dual specificity CDC25 phosphatases dephosphorylate two inhibitory phospho-amino acids of cyclin-dependent kinases, a major family of cell cycle regulators. CDC25 inhibitors constitute new anti-mitotic agents with potential anticancer activity. While screening through a collection of natural products derived from marine organisms for CDC25A inhibitors, we purified and identified coscinosulfate 1, a sesquiterpene sulfate from the New Caledonian sponge Coscinoderma matthewsi, along with 4. The purified compound 1 displayed significant inhibitory activity towards CDC25A (IC(50): 3 microM).

New bromoditerpenes from the red alga Sphaerococcus coronopifolius

The organic extract of the red alga Sphaerococcus coronopifolius, collected along the Atlantic coast of Morocco, was tested for biological activities and exhibited antibiotic and antimalarial activities. Two new bromoditerpenes have been isolated from S. coronopifolius, sphaerolabdadiene-3,14-diol (1) and bromosphaerone (2), along with the known compounds 12S-hydroxybromosphaerodiol (3) and sphaerococcenol A (4). Bromosphaerone and 12S-hydroxybromosphaerodiol showed antibacterial activity against the Gram-positive bacterium species Staphylococcus aureus with a minimum inhibitory concentration of 0.104 and 0.146 microM, respectively. Sphaerococcenol A (4) was responsible for the antimalarial activity of the extract, against the chloroquine resistant Plasmodium falsciparum FCB1 strains with an IC(50) of 1 microM. Their structures have been assigned using 1 and 2 D NMR and HRMS.

16Beta-hydroxy-5alpha-cholestane-3,6-dione, a novel cytotoxic oxysterol from the red alga Jania rubens

A new cytotoxic oxysterol, 16beta-hydroxy-5alpha-cholestane-3,6-dione was isolated from the red alga Jania rubens. Its structure was established by spectroscopic method. The ID50 value was 0.5 microg/mL.

[Malignant or necrotizing otitis externa: experience in 22 cases]

Malignant or progressive necrotizing otitis extrema is an uncommon but severe infectious condition of the external auditory canal. Over a period of four years, we treated 22 patients: 60% had diabetes (1/4 insulin dependent) and 13% were immunodepressed. The causal germ was Pseudomonas aeruginosa in 87% of cases. The pretherapeutic work-up included a computed tomography scan and a technetium scintigraphy to confirm diagnosis and assess extension. Repeated scintigraphies with gallium were used to follow the course under treatment. Medical treatment was used in most cases (16/22) with parenteral antibiotic therapy using a third-generation cephalosporin (ceftazidime or ceftriaxone) and a fluoroquinolone (ciprofloxacin or ofloxacin) and, if there was no contraindication, hyperbaric oxygen. Surgery is not indicated in malignant otitis externa. We had a 95% cure rate with only 10% recurrence. We reviewed the data in the literature on malignant otitis externa and present the important diagnostic, imaging and therapeutic aspects.

Design and in vitro evaluation of adhesive matrix for transdermal delivery of propranolol

Propranolol hydrochloride, a water-soluble drug, was incorporated in three transdermal delivery systems using three polymers (hydroxypropylmethylcellulose, polyisobutylene and Ucecryl MC808). The influence of different factors (polymeric material, matrix thickness, drug content, thickness of the adhesive layer and presence of a dissolution enhancer) was investigated. Microscopic observations and DSC thermograms have permitted to demonstrate that propranolol was essentially dissolved in the HPMC matrix and dispersed in the two other matrix types. In vitro dissolution study was carried out according to European Pharmacopoeia. Release from HPMC matrices without adhesive coating was fast. Release from these matrices became more regular (reduction of the burst effect) and slow when they are coated with a 12 microm thick Ucecryl layer. Release from different PIB matrices was too slow to be suitable as TDDS for propranolol. The best release modulation was obtained from Ucecryl matrices. In all matrices types, propylene glycol accelerated propranolol release rate. The kinetic of drug release from most matrix types was more closely described by the square-root model (Higuchi).

New lipids from the tunicate Cystodytes cf. dellechiajei, as PLA2 inhibitors

Cystodytes cf. dellechiajei collected off Djerba furnished new lipids, sphingosines 1, as inhibitors of phospholipase A2, along with inactive homologous ceramides 2. Structures were determined by spectroscopic methods and chemical transformations.

Methanol adduct of puupehenone, a biologically active derivative from the marine sponge Hyrtios species

A methanol adduct of puupehenone (1), 15alpha-methoxypuupehenol (2), an artifact resulting from the action of MeOH on puupehenone, was isolated during purification of the CH(2)Cl(2) extract of the New Caledonian marine sponge Hyrtios sp., as the major constituent. Its chemical structure was elucidated by 2D NMR experiments. Compound 2 displayed similar antimicrobial and antifungal activity as puupehenone and a lower cytotoxic activity toward KB cells with ED(50) values of 6 and 0.5 microg/mL, respectively. Compound 2 was slightly more active against three strains of Plasmodium falciparum than puupehenone.

Optimized radioiodine therapy of Graves' disease: analysis of the delivered dose and of other possible factors affecting outcome

The best approach to radioiodine dose selection in the treatment of Graves' hyperthyroidism remains highly controversial. The formula to calculate the individual dose of (131)I to be delivered has been used for half a century and takes into account the thyroid mass, the effective half-life and the maximum uptake of (131)I. The objective of the present study was to evaluate the accuracy of this formula by determining the relationship between the administered dose of (131)I calculated to deliver a target dose of 50Gy to the thyroid and the actual exact organ dose. We further analyzed if therapeutic success, defined by euthyroidism following the individually calculated dose, can be predicted by different pretreatment parameters and particularly by organ dose. One hundred patients with a first episode of Graves' disease and who had received optimal thyroid irradiation after precise dosimetry were retrospectively reviewed. The patients were categorized according to their thyroid function (plasma free thyroxine (T(4)) serum concentration) as eu-, hyper- or hypothyroid during and 1 year after treatment. The relationship between the administered dose and organ dose was assessed by simple regression. We compared free T(4), free tri-iodothyronine, thyroid weight, the number of patients with antithyroperoxidase antibodies and TSH receptor autoantibodies, 24h urinary iodine excretion, (131)I uptake, and the exact dose of (131)I delivered to the thyroid as pretreatment variables. Although we found a correlation between administered dose (mCi) and organ dose (Gy) (r=0.3, P=0.003), the mean coefficient of variation for organ dose was 45%. Individualized radioiodine therapy enabled euthyroidism in 26% of patients and failed in 74% of patients (33% had persistent or recurrent hyperthyroidism and 41% permanent hypothyroidism). (131)I uptake was significantly higher in the hyperthyroidism group in comparison with the euthyroid group. However, organ dose and other pretreatment variables did not differ among the three groups. In conclusion, these results confirm the low performance of individual dosimetry using what are established ratios, since the delivered dose to the gland, although correlated to the intended dose, is highly variable. The finding that other usual pretreatment variables are not different between groups, gives little hope for improving the way of calculating the ideal dose of radioiodine. We suggest to those not yet ready to give a standard or an ablative dose for Graves' hyperthyroidism that they abandon this way to calculate the (131)I dose.

Metabolites from the Sponge-Associated Bacterium Pseudomonas Species

: Quinolones and a phosphatidyl glyceride were isolated from the sponge-associated bacterial strain Pseudomonas sp. Structures were elucidated by spectroscopic analysis and chemical transformations.

Evaluation of indium-111 pentetreotide somatostatin receptor scintigraphy to detect recurrent thyroid carcinoma in patients with negative radioiodine scintigraphy

The follow-up of patients who underwent thyroidectomy for differentiated thyroid carcinoma is based on the combination of serum thyroglobulin (Tg) measurement and radioiodine total-body scan (ITBS). The diagnostic strategy to be used in patients with elevated serum Tg level but negative ITBS remains debatable. Somatostatin receptor scintigraphy (SRS) has been proposed. Our objective was to compare the results of SRS and conventional radiological imaging (CRI) for the diagnosis of recurrent disease and/or metastases in 15 patients who had had thyroidectomy for differentiated carcinoma (14 papillary, 1 Hurthle cell carcinoma) and who displayed elevated Tg levels (10 to 65000 ng/mL) together with negative ITBS performed after 100 mCi. All patients underwent SRS and CRI within 3 months, allowing comparison of the 2 approaches for the identification of thyroid carcinoma metastases. CRI first included a chest x-ray and ultrasonography of the neck. It was followed by computed tomography (CT) scanning and/or magnetic resonance imaging (MRI) of the neck, chest and occasionally abdomen, and 99mTc bone scintigraphy in case of negative results. In 6 patients with Tg levels ranging from 65 to 65000 ng/mL, CRI detected 12 histologically proven metastases among 9 organs. Among these patients, SRS identified only 6 metastases. SRS identified 1 case of mediastinal recurrence that was not detected by CRI. In another patient with a Tg level of 51 ng/mL, a cervical node was identified using both SRS and CRI but proved to be a false-positive (inflammatory cervical node). In the other 8 patients with Tg levels ranging from 10 to 580 ng/mL, SRS and CRI were negative, and the source of Tg secretion remains unknown. The results of SRS did not correlate with serum Tg level. In conclusion, the diagnostic accuracy of SRS in this study was disappointing and clearly lower than that of CRI. Our results do not support the use of SRS as a guide conventional imaging modalities in patients operated on for differentiated thyroid carcinoma who display elevated Tg levels together with negative ITBS.

Familial non-medullary thyroid carcinoma: pathology review in 27 affected cases from 13 French families

BACKGROUND AND OBJECTIVES

When familial non-medullary thyroid cancer (FNMTC) develops with no obvious associated pathogenetic factor, an inherited predisposition may underlie the process. The present study was conducted because detailed pathological findings are lacking in most series of FNMTC.

PATIENTS AND METHODS

Thirteen families comprising 27 cases of FNMTC were included (1.8% of differentiated thyroid carcinoma). The family relationship (20 F, 7 M; age 46 +/- 16 years; mean +/- SD) was 'siblings' in eight families, 'parent and child' in four and 'aunt and niece' in one. Careful pathological review of the thyroid tumours (papillary/follicular: 25/2, size: 16 +/- 11 mm) was performed.

RESULTS

Initial staging according to extension was as follows: grade I (n = 16), II (n = 2), III (n = 6), IV (n = 3). Fourteen tumours were papillary microcarcinomas (size: 8 +/- 2 mm). No tumour phenotype that may be considered specific for FNMTC was found when considering either age, pathological findings or tumour aggressiveness. Although rare events were found in both relatives of some families suggesting a putative 'familial' phenotype of FNMTC, this may be fortuitous.

CONCLUSION

Micro familial non-medullary thyroid cancers are more common than previously reported and further studies are required to be able to distinguish this subgroup from sporadic papillary microcarcinomas. The careful pathological review of the familial non-medullary thyroid cancer in this study does not seem to point to a distinct subgroup of familial differentiated thyroid carcinoma although the data are intriguing. Genetic studies are now required to investigate this issue.

Interest of colchicine for the treatment of cystic fibrosis patients. Preliminary report

Cystic fibrosis (CF) lung disease is characterized by persistent inflammation. Antiinflammatory drugs, such as corticosteroids and ibuprofen, have proved to slow the decline of pulmonary function although their use is limited because of frequent adverse events. We hypothesized that colchicine could be an alternative treatment because of its antiinflammatory properties and upregulatory effect on cystic fibrosis transmembrane regulator (CFTR) closely related proteins. We herein present results obtained in an open study of eight CF children treated with colchicine for at least 6 months. Clinical status was better in all patients and respiratory function tests significantly improved in five. Median duration of antibiotherapy decreased significantly. These preliminary results support our hypothesis of a beneficial effect of colchicine in CF patients and stress the need for a controlled therapeutic trial.

Functional specialization of stable and dynamic microtubules in protein traffic in WIF-B cells

We found that the magnesium salt of ilimaquinone, named 201-F, specifically disassembled dynamically unstable microtubules in fibroblasts and various epithelial cell lines. Unlike classical tubulin- interacting drugs such as nocodazole or colchicine which affect all classes of microtubules, 201-F did not depolymerize stable microtubules. In WIF-B-polarized hepatic cells, 201-F disrupted the Golgi complex and inhibited albumin and alpha1-antitrypsin secretion to the same extent as nocodazole. By contrast, 201-F did not impair the transport of membrane proteins to the basolateral surface, which was only affected by the total disassembly of cellular microtubules. Transcytosis of two apical membrane proteins-the alkaline phosphodiesterase B10 and dipeptidyl peptidase IV-was affected to the same extent by 201-F and nocodazole. Taken together, these results indicate that only dynamically unstable microtubules are involved in the transport of secretory proteins to the plasma membrane, and in the transcytosis of membrane proteins to the apical surface. By contrast, stable microtubules, which are not functionally affected by 201-F treatment, are involved in the transport of membrane proteins to the basolateral surface. By specifically disassembling highly dynamic microtubules, 201-F is an invaluable tool with which to study the functional specialization of stable and dynamic microtubules in living cells.