Beta-keto-ester chemistry and ketolides. Synthesis and antibacterial activity of 2-halogeno, 2-methyl and 2,3 enol-ether ketolides

The effect of 2,3 modifications on the antibacterial activity of ketolides was evaluated by introducing substituents in position 2 and converting the C-1, C-2, C-3 beta-keto-ester into stable 2,3 enol-ether or 2,3 anhydro derivatives. Introduction of a fluorine in C-2 is beneficial with regard to the overall antibacterial spectrum whereas the enol-ether and 2,3 unsaturated compounds, as well as the bulky gem dimethyl or 2-chloro derivatives, are less active particularly against erythromycin resistant strains. A 2-fluoro ketolide derivative demonstrates good antibacterial activity and in vivo efficacy against multi-resistant Streptococcus pneumoniae. Compared to azithromycin against Haemophilus influenzae, this compound is equivalent in vitro and slightly more active in vivo. These results demonstrate that within the ketolide class, to retain good antibacterial activity, position 2 needs to remain tetrahedral and tolerates only very small substituents such as fluorine.

[Subcutaneous myiasis. A case report]

Although myiasis or hypodermiasis is a parasitic disease that theoretically has practically been eradicated, a new case has recently been reported in Lower Normandy, in a bovine husbandry region.

CASE REPORT

A seven-year-old-girl was hospitalized in November 1998 for an edema of variable size on the right eyelid, which was not painful and non-inflammatory, with accompanying ptosis. A number of subcutaneous nodules were found on the forehead above the right eye socket. The right eye itself was unaffected. The symptoms had evolved over a ten-day period. Further examination did not detect any sign of eosinophilia, and the hypodermiasis and toxocariasis serologies were negative. The clinical evolution was characterized by the regression and reappearance of the edema on several occasions, after which the edematous mass became progressively larger, more swollen and painful, so that it was no longer possible to open the eye. The subcutaneous nodules partially disappeared when the edema increased in size. Six weeks after the onset of clinical signs, eosinophilia was observed and the hypodermiasis serology was positive. Due to the limitation of the visual field as a result of the edema, a short-term steroid treatment (seven days) was orally administered. The patient recovered, and no further edematous signs were noted. However, contrary to what had been reported in the literature, the larvae did not appear on the surface of the skin.

CONCLUSION

In conclusion, in bovine husbandry regions the diagnosis of hypodermiasis should always be kept in mind in the event of clinical signs indicative of larval migration, even in the initial absence of eosinophilia, and even with an initially negative hypodermiasis serology. This disease should soon be eradicated, as regional bovine treatment programs have been set up to systematically treat the cattle and eliminate the larvae.

Structure and composition of the aragonitic crossed lamellar layers in six species of Bivalvia and Gastropoda

The microstructures, the chemical composition and the soluble organic matrices of the aragonitic crossed lamellar layers of the shells of six species of molluscs have been studied. The microstructures and chemical contents are similar, whereas the quantities of organic matrices are variable. All the soluble matrices are glycoproteins, with low S contents. Their molecular weights, the protein-sugar ratios and acidities are variable. Neither a gastropod nor a bivalve pattern is recognized. The diversity of the organic matrices probably plays a main role in the fossilization processes of mollusc shells.

[Effects of a sequential combination of estradiol valerate and cyproterone acetate on the functional properties of the arterial wall in menopausal women]

Several studies have shown that estrogen replacement therapy protects postmenopausal women against coronary artery disease. This protective effect has been ascribed to the hormone's effect on serum lipids, as well as a direct action on the vascular wall. Concurrent administration of a progestin to protect women from the risk of endometrial hyperplasia may alter the protective effects of estrogen. The aim of this study was to assess the evolution of the endothelial function in postmenopausal women given a sequential combination of oral 2 mg estradiol valerate for 11 days, followed by 2 mg estradiol valerate associated with 1 mg cyproterone acetate for ten days (Climène). Each 21-day sequence was followed by a seven-day treatment-free interval. The women received a three-month treatment course. Thirty-one healthy postmenopausal women participated in the study (median age: 51 years; range: 45-59 years). Flow-mediated dilatation (FMD), a reflection of endothelium-dependent vasomotor function, increased from 8.47% at baseline (range: 4.57-11.02%) to 9.64% (range: 7.07-13.12%) at the end of the first treatment cycle; i.e., a 15% increase over baseline (P < 0.0001). FMD further increased after three treatment cycles to 10.59% (range: 8.09-15.22%); i.e., a 28.6% increase over baseline (P < 0.0001). FMD at the end of the first combined sequence or after the 11 days of estradiol only were similar (delta = 0.25%; range: -2.31-5.81%; not significant). In conclusion, in postmenopausal women, a three-month sequential treatment combining estradiol valerate and estradiol valerate plus cyproterone acetate (Climène) has beneficial effects on endothelial function as demonstrated by the evolution of the FMD. There was no decrease in the effect of estradiol on FMD when cyproterone acetate was added to estradiol.

Synthesis and antibacterial activity of HMR 3647 a new ketolide highly potent against erythromycin-resistant and susceptible pathogens

In the search for new ketolides with improved activities against erythromycin-resistant S. pneumoniae and H. influenzae we synthesized a new 11,12 carbamate ketolide substituted by an imidazo-pyridyl side chain: HMR 3647. This compound demonstrated a potent activity against erythromycin susceptible and resistant pathogens, including penicillin G/erythromycin A-resistant S. pneumoniae and H. influenzae. In vivo, HMR 3647 displayed good pharmacokinetic parameters (Cmax = 2.9 microg/ml, bioavailability=49%, AUC0.8 = 17.2 microg.h/l, t1/2=1h) and was shown to have a high therapeutic efficacy in mice infected by various respiratory pathogens, including multi-resistant S. pneumoniae and Gram negative bacteria such as H. influenzae. HMR 3647 appears to be a very promising agent for the treatment of respiratory infections and is currently in clinical trials.

Immediate pigment darkening: description, kinetic and biological function

Immediate pigment darkening (IPD) is a transitory darkening of the skin observed after UVA exposure. The melanocytic system is implicated in its development. Indeed, it involves structural changes in melanocytes and keratinocytes and a chemical modification of pre-existing melanin. Darkening intensity is maximum immediately after exposure and decreases rapidly. The maximum efficiency wavelength for induction of IPD is around 340 nm. The phenomenon is inhibited by oxygen deprivation. Dose-response curves are linear for doses above 4 J/cm2. Minimum dose for induction of IPD (MIPDD) varies with the subject according to phototype, melanotype and skin color. The best criterion for predicting MIPDD seems to be chromametrically determined skin color. The biological role of IPD remains poorly understood; several hypotheses are discussed.

Cytogenetics of uterine sarcomas: presentation of eight new cases and review of the literature

Tissue from 14 uterine tumor samples from eight patients-four with endometrial stromal sarcoma (ESS), two with leiomyosarcoma (ULMS), and two with malignant mixed mesodermal tumor (MMMT)-were investigated cytogenetically after short-term culturing. Clonal chromosome aberrations were found in 12 tumors. One ESS showed a recombination between 7p14 and 17q12, a rearrangement characterizing a subset of ESSs. In our series, chromosomes 1, 6, 7, and 16 were involved in structural aberrations most frequently (four cases each). Net loss of 6q material was found in four cases and bands 11q13, 16q13, and 22q13 were each rearranged in four cases. Among 43 uterine sarcomas, including 12 MMTs, now available for evaluation, some differences in breakpoint distribution among different tumor types were found. Rearrangements of bands 1p32, 3p24, and 10q22 were found exclusively in ULMS, whereas aberrations of bands 6p21, 7p21, and 17q12 were found predominantly in ESS.

Synthesis and antibacterial activity of ketolides (6-O-methyl-3-oxoerythromycin derivatives): a new class of antibacterials highly potent against macrolide-resistant and -susceptible respiratory pathogens

In the search for new antibiotics active against macrolide-resistant pneumococci and Haemophilus influenzae, we synthesized a new class of 3-oxo-6-O-methylerythromycin derivatives, so-called "ketolides". A keto function was introduced in position 3 after removal of L-cladinose, a sugar which has long been thought essential. Further modifications of the macrolactone backbone allowed us to obtain three different series of 9-oxime, 11,12-carbamate, and 11, 12-hydrazonocarbamate ketolides. These compounds were found to be very active against penicillin/erythromycin-resistant pneumococci and noninducers of MLSB resistance. The 11,12-substituted ketolide 61 (HMR 3004) demonstrated a potent activity against multiresistant pneumococci associated with a well-balanced activity against all bacteria involved in respiratory infections including H. influenzae, Mycoplasma catarrhalis, group A streptococci, and atypical bacteria. In addition HMR 3004 displayed high therapeutic activity in animals infected by all major strains, irrespective of their resistance phenotype.

Cytomorphometric analysis of vaginal cells during normal cycle, under oral contraceptive therapy or in-vitro fertilization stimulation protocol

A cytomorphometric analysis of superficial vaginal cells in women in three groups of different types of hormonal concentration was made. There were 15 women in each group. Group I was studied during a natural cycle, group II under oral contraceptive therapy and group III during an in-vitro fertilization (IVF) stimulation protocol. Morphometric parameters were measured on an image analyser. The area, perimeter and several form factors were measured separately for nuclei and cytoplasm. The nucleus:cytoplasmic ratio was also determined. The cytoplasmic area was significantly reduced in group II and was associated with a statistically significant reduction of the nuclear area. The nucleus:cytoplasmic ratio appeared significantly increased in group II and reduced in group III. Low oestradiol impregnation obtained with an oral minidosed contraceptive interfered with vaginal cell maturation. High oestradiol concentrations obtained during IVF protocols induced marked nuclear pycnosis but did not induce supra-physiological cell enlargement. Maximal cell size is genetically regulated according to Driesch's law of volume invariance and hormonal over-stimulation has no effect on cell size. The nucleus:cytoplasmic ratio appears to be a powerful parameter reflecting the opposite effects of hormones on cell compartments.

Synthesis of 6-O-methyl-azithromycin and its ketolide analogue via Beckmann rearrangement of 9(E)-6-O-methyl-erythromycin oxime

The synthesis of 6-O-methyl-azithromycin and its aza-ketolide analogue have been achieved by carrying out the Beckmann rearrangement of the readily available 9(E)-6-O-methyl-erythromycin oxime 1. In contrast to the C14 ketolides like HMR 3647, the aza-ketolide turns out to be inactive, thus demonstrating that the addition of a 3 keto function and ring expansion, from 14 to 15 membered ring, could be deleterious for the antibacterial activity.

Parachordoma: a rare sarcoma with clonal chromosomal changes

This is the first report on clonal chromosomal aberrations in a metastatic parachordoma lesion. All neoplastic cells had the karyotype 33-47,X,der(X)t(X;3) (p11;p11),der(3)t(3;6)(p11;q13), del(6)(q13), -9, -13,r(13), +mar. The presence of t(X;3) with a breakpoint at band Xp11 as in synovial sarcoma may suggest a common histological origin of the two tumor types.

Translocation (X;1)(p11.2;q21) in a papillary renal cell carcinoma in a 14-year-old girl

We report a case of papillary renal cell carcinoma with the karyotype 43-46,X,t(X;1) (p11.2;q21)[5]/80-88,idemx2[5]/45-86,idem,add(5)(p15.1)[2]. This is the second case with such a translocation documented in papillary renal cell carcinoma in a young female.

Effects of long-term treatment with recombinant human erythropoietin on physiologic inhibitors of coagulation

Recombinant human erythropoietin (rHu-EPO) in the treatment of renal anemia might predispose to an increased risk of thrombotic complications. In an attempt to comprehend the involvement of the physiologic inhibitors of coagulation in this process, we studied 2 groups of hemodialysis patients. Group I included 21 patients receiving a starting dose of 90 IU/kg/week s.c., and group II included 17 patients without rHu-EPO. The following coagulation tests were performed before rHu-EPO treatment, and after 1, 6 and 12 months: prothrombin time; activated partial fistula thromboplastin time; fibrinogen; plasminogen activity; antithrombin III activity; protein C activity; total and free protein S antigens, and C4b binding protein. Only the latter three parameters were changed in group 1, while high baseline levels of protein S antigens were found in both groups. A decrease in total and free protein S was observed within 1 month of treatment. At the 6th month total protein S returned to near pretreatment values, whereas a significant fall in free protein S (p = 0.007) was observed. All three parameters returned to near baseline values by 12 months. These results suggest that protein S activity can be altered at the beginning of EPO therapy, a change that under favoring circumstances might contribute to the thrombotic events reported during the early phase of rHu-EPO treatment.

Pulsed photoacoustic study of the diffusion of chromophores in human skin

The technique of pulsed photoacoustic spectroscopy was used to investigate the diffusion of chromophores in human skin. The kinetic of diffusion has been studied for five solutions at different concentrations in a mixture of chromophores, as used in commercial sunscreens. In addition to the classical macroscopic interpretation of the diffusion process, a new method is shown to give more detailed information on chromophore presence at different depths in skin. For the first time, results are expressed in the frequency domain by means of the Fourier transform applied to the photoacoustic signal. The spectra are discussed versus the depth in skin samples and the time of diffusion kinetics. This new method of data analysis is shown to be very useful for understanding the influence of the internal structure of a medium on the penetration rate of chromophores into skin.

Temporality and modes of language

After reviewing some literary, philosophical and psychoanalytic conceptions of time, the author distinguishes between the sensation of time, in which rhythm is all-important, and its representation. The timeless unconscious, which can, however, be rendered temporal through the transference, is contrasted with the sequential chronology of preconscious and conscious functioning. Language, and in particular metaphorical language, is deemed to play a vital part in the structuring of the psyche, and is mediated by the object; the contingency of metaphor is held to be essential because otherwise the object will impose itself too directly, causing the previously undifferentiated death drive to predominate. A primal temporality must, in the author's view, have been laid down in the form of an unrepresentable auto-erotic datum before the individual can perceive himself as a living subject and conceive of lineal and irreversible time with its implications of castration and death; there is no such thing as a timeless subject. All pathologies of temporality are considered by the author to be at the same time pathologies of subjectivation and of language. The paper ends with a clinical illustration in which a key time-related defence of the patient is overcome by an intervention outside the strict time frame of the setting that proves mutative and enables her to recover her personal rhythm as a subject.