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Cationic carbon dots were fabricated by pyrolysis of citric acid and bPEI25k under microwave radiation. Various nanoparticles were produced in a 20-30% yield through straightforward modifications of the reaction parameters (stoichiometry of the reactants and energy supply regime). Particular attention was paid to the purification of the reaction products to ensure satisfactory elimination of the residual starting polyamine. Intrinsic properties of the particles (size, surface charge, photoluminescence and quantum yield) were measured and their ability to form stable complexes with nucleic acid was determined. Their potential to deliver plasmid DNA or small interfering RNA to various cell lines was investigated and compared to that of bPEI25k. The pDNA in vitro transfection efficiency of these carbon dots was similar to that of the parent PEI, as was their cytotoxicity. The higher cytotoxicity of bPEI25k/siRNA complexes when compared to that of the CD/siRNA complexes however had marked consequences on the gene silencing efficiency of the two carriers. These results are not fully consistent with those in some earlier reports on similar nanoparticles, revealing that toxicity of the carbon dots strongly depends on their protocol of fabrication. Finally, these carriers were evaluated for in vivo gene delivery through the non-invasive pulmonary route in mice. High transgene expression was obtained in the lung that was similar to that obtained with the golden standard formulation GL67A, but was associated with significantly lower toxicity. Post-functionalization of these carbon dots with PEG or targeting moieties should significantly broaden their scope and practical implications in improving their in vivo transfection efficiency and biocompatibility., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A new analytical formalism has been published recently that provides all the parameters necessary for geometrical field matching in radiotherapy. The present work applies the general expressions for craniospinal irradiation, breast irradiation with a supraclavicular half-field, and breast irradiation with a supraclavicular full-field. We also explore the formalism as a tool to analyze and compare different techniques. Field matching is achieved by imposing both parallelism and coincidence between the side planes of adjacent fields. The rotation angles and either the field aperture for a certain isocenter position or the isocenter coordinates for a given field aperture are supplied. All of the already known exact solutions are reproduced. New expressions for the field aperture and for the isocenter coordinates, which were not previously available, are also computed. If tangential fields at a fixed source-to-skin distance are used together with a supraclavicular full-field, different apertures for each tangential field are required to achieve a correct match. If an isocentric technique for the tangential fields or a supraclavicular half-field is used, this complication is avoided. The breast technique with the supraclavicular half-field is recommended, because it presents several advantages with respect to the supraclavicular full-field. This formalism provides a useful tool in cases where matching of adjacent fields is necessary., (Copyright © 2011 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.)

In this study, the ability of synthetic fluorinated lipospermines to bind DNA and siRNA was investigated and the transfection efficiency and toxicity of the resulting lipoplexes in cell lines were evaluated. Three lipopolyamines displaying fluorous tags close to their cationic polar head ("HFP" polyamines) were synthesized. Their ability to condense pDNA and siRNA, and to form nanoparticles were characterized. Lipoplex stability was investigated in the presence of different surface active compounds and was shown to be significantly improved due to the presence of the fluorous tags. Transfection efficiencies were studied in HepG2 and 911 cell lines, and compared to that of DOGS, DOTAP, and Lipofectamine 2000. Also, the ability of these compounds to deliver nucleic acids into cells in the presence of high concentration of serum was quantified. By incorporating two fluorous tags in the direct vicinity of the polycationic head group of the lipospermines, we show efficient pDNA and siRNA formulation, and delivery to cultured cells. Fluorinated lipoplexes exhibit improved stability in the presence of amphiphilic compounds and retain high transfection efficiency in the presence of 50-75% serum. These results demonstrate that lipospermines displaying fluorous tags close to their cationic polar head bind to and deliver pDNA and siRNA with high cell viability in different cell lines. They are efficient non-viral vectors that exhibit remarkable serum compatibility., (Copyright 2010 Elsevier Ltd. All rights reserved.)

In the present study, we have assessed the effect of the peroxisome proliferator-activated receptor-alpha (PPARalpha) agonist fenofibrate on allergen-induced airway inflammation and immune response. C57BL/6 or PPARalpha knock-out (PPARalpha(-/-)) mice were sensitized with ovalbumin and challenged with ovalbumin alone or with ovalbumin+lipopolysaccharides. Fenofibrate was administered to allergen-exposed animals during challenge only or from the day prior to sensitization to the end of challenge. Inflammation and immune response were assessed by determining cell counts and cytokine levels in bronchoalveolar lavage fluids, expression of the transcription factors Gata-3 and T-bet in lung tissue and ovalbumin-specific IgE and IgG2a in serum. Treatment with fenofibrate (0.15-15 mg/day) during allergen challenge dose-dependently reduced airway inflammatory cell infiltrate induced by ovalbumin in C57BL/6 mice. Reduction reached 74.3% (P<0.001) in animals treated with 15 mg/day of the PPARalpha agonist, whereas this treatment failed to suppress cell infiltrate induced by allergen in PPARalpha(-/-) mice. In addition, when administered from the day prior to sensitization to the end of challenge, fenofibrate (15 mg/day) triggered switching of the immune response to allergen towards a Th1 profile, as evidenced by an increase in IgG2a levels, a reduction in IL(interleukin)-4 and IL-5 together with an increase in interferon-gamma, and a decrease in Gata-3/T-bet expression ratio. Upon challenge with ovalbumin+lipopolysaccharides, sensitized mice developed a severe inflammatory response characterized by infiltration of eosinophils, neutrophils, lymphocytes and macrophages and by increased release of IL-4, IL-5, tumor necrosis factor-alpha, macrophage-inflammatory protein-2 and monocyte chemoattractant protein-1. Administration of fenofibrate during allergen challenge dramatically reduced all responses. In conclusion, our data clearly demonstrate that fenofibrate exhibits an anti-inflammatory activity in allergic asthma, including in severe conditions, and that the PPARalpha agonist is also capable of switching the immune response to allergen towards a Th1 profile when given from the day prior to sensitization.

Annexin 1 is secreted by mammalian cells but lacks a leader signal sequence necessary to lead it to the classical secretory pathway via the endoplasmic reticulum. The mechanisms involved in the secretion of leaderless proteins remain uncertain. It has been suggested to involve membrane translocation via an ABC-transporter (ATP binding cassette). Using cultured inflamed mucosa from rectocolitis induced in rats, we studied if annexin 1 secretion followed the two main characteristics of ABC-transporter substrates: dependency on ATP hydrolysis and competitive inhibition by several other ABC-transporter substrates. Annexin 1 secretion is inhibited in a dose-dependent manner by two ATPase inhibitors. The inhibition reached 63.2+/-3.2%, 66.1+/-3.73% and 88.6+/-1.4% in the presence of 2mM vanadate, 0.5 and 1mM pervanadate, respectively. The efflux of calcein, a known ABC-transporter substrate, is similarly inhibited by 69.4+/-2.8% in the presence of 1mM pervanadate. Probenecid, an inhibitor of several ABC-transporters of the subfamilly ABCC or MRP (multidrug resistant associated protein), also inhibited annexin 1 secretion in a dose-dependent manner. As compared to control, 10mM probenecid reduced annexin 1 secretion by 72+/-20% and 20mM by 95.0+/-9%. By contrast, annexin 1 secretion is not blocked by other inhibitors of MRP1 (indomethacin, MK571), MRP2 (ochratoxin A1 or MK571), MRP5 (trequinsin or sulfinpyrazone) or by verapamil, cyclosporin A or glyburide. Taken together, our results show that annexin 1 secretion appears to share the efflux properties of ABC-transporter substrates.

Water-in-fluorocarbon reverse emulsions and microemulsions stabilized by semi-fluorinated amphiphiles derived from the dimorpholinophosphate polar head group, C(n)F(2n+1)(CH(2))(m)OP(O)[N(CH(2)CH(2))(2)O](2) (FnHmDMP), are being investigated as new delivery systems for drugs or genetic materials into the lung. Since information related to the toxicity of fluorinated surfactants is still very limited, we evaluated herein the cytotoxicity of a series of FnHmDMP (n=4, 6, 8 and 10 and m=2, 5, and 11). Both solutions of FnHmDMP in fluorocarbons, and reverse water-in-fluorocarbon emulsions stabilized by FnHmDMP were assessed in order to determine the relation between surfactant structure and cell toxicity, and select the most innocuous emulsifier. A first short-term evaluation on mouse fibroblasts using a viability/cytotoxicity assay indicated that amphiphiles (in solution) with a chain length longer than C12 exhibit less toxicity than amphiphiles with shorter chain. Moreover cytotoxicity decreased also with length of the fluorinated segment. The protective effect of the fluorinated chain was strongly supported by the fact that the hydrogenated analog, C(15)H(31)OP(O)[N(CH(2)CH(2))(2)O](2) (H15DMP), was highly toxic. Qualitative evaluation on human lung epithelial cells (HLEC) using a colorimetric method (Mayer's hematoxylin) confirmed that amphiphiles (in solution) with longer chain were the least cytotoxic. The protective effect of the fluorinated chain appeared, however, to be significant only at low amphiphile concentrations (0.1% w/v). In contrast, at higher concentrations (1% and 5% w/v), the total chain length was the determining factor. Quantitative evaluation of the least cytotoxic amphiphiles using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method then showed that F10H11DMP (in solution) was harmless until its solubility limit (1% w/v); cell growth was even enhanced due to improved oxygenation provided by the fluorocarbon phase. F8H11DMP exhibited some cytotoxicity at both 1% and 5% w/v, but the toxicity appeared to level off with concentration. Reverse water-in-perfluorooctyl bromide (PFOB) emulsions stabilized by either F10H11DMP or F8H11DMP were found to be non-cytotoxic. In conclusion, the present evaluation indicates that the cytotoxicity of FnHmDMP depends on both total and fluorinated amphiphile chain length, and leads us to select F8H11DMP and F10H11DMP as the less cytotoxic amphiphiles among a series of FnHmDMP compounds. Furthermore, water-in-fluorocarbon emulsions stabilized with F8H11DMP and F10H11DMP appeared to be non-cytotoxic towards HLEC in culture.

The aim of this study was to investigate the usefulness of biochemical markers of bone turnover for monitoring treatment efficacy of Paget's disease of bone, and also to evaluate the utility of biological variation data in choosing the best markers for assessment of biochemical response to therapy. Thirty-eight patients with Paget's disease were included in a prospective study. All received 400 mg/day of oral tiludronate for 3 months. In 31 patients that completed treatment, biochemical markers were measured at baseline and at 1 and 6 months after treatment ended. In serum we determined the levels of total alkaline phosphatase (tAP), bone alkaline phosphatase (bAP), procollagen type I N-terminal propeptide (PINP), and C-terminal telopeptide of type I collagen (sCTx). Urine samples were analyzed for hydroxyproline (Hyp) and for C- and N-terminal telopeptides of type I collagen (CTx and NTx, respectively). Quantitative bone scintigraphy was performed at baseline and at 6 months after discontinuation of therapy. A ratio for monitoring response to treatment was obtained for each marker. This ratio reflected the size of treatment response of the marker in relation to the value of its critical difference. Thus, ratio values of >1 indicated a significant decrease of the marker after therapy. In addition, response to therapy was evaluated according to disease activity. Mean values of all markers of bone turnover decreased significantly after therapy. Serum bAP and PINP and urinary NTx showed the highest percentage reduction (between 58% and 68%). Furthermore, serum bAP and PINP showed the highest ratios for monitoring changes induced by treatment, followed by serum tAP and urinary NTx. sCTx and urinary CTx as well as Hyp showed mean ratios for monitoring changes of <1, indicating a low sensitivity for monitoring treatment. Patients with polyostotic disease showed a continuous decrease in mean values for all markers at 6 months from the end of therapy, whereas, in monostotic patients, there was a trend toward increased levels at this timepoint. In conclusion, serum bAP and PINP were the most sensitive markers for monitoring treatment efficacy in Paget's disease, although serum tAP and urinary NTx were also sensitive markers for monitoring changes. Data on biological variation are useful for assessing actual changes induced by treatment.

Nerve growth factor (NGF) has recently been presented as a possible effector of inflammation and bronchial hyperresponsiveness. However, the production of NGF in human airways as well as the regulation of its expression by inflammatory cytokines and glucocorticoids have received little attention. A549 epithelial cells were cultured in Dulbecco's modified Eagle's medium supplemented with 10% foetal bovine serum, and starved for 24 h. The effect of the pro-inflammatory cytokine interleukin-1beta (1-30 U/ml), and of the glucocorticoid dexamethasone (1 microM) on NGF secretion was studied and quantified by enzyme-linked immunosorbent assay (ELISA). In addition, NGF production within the cells was visualized by immunocytochemistry. Under basal conditions, A549 cells produced and secreted NGF (12.6+/-2.0 pg/ml). Stimulation by interleukin-1beta for 24 h induced a dose-dependent increase in NGF production (maximal at 10 U/ml with 59.6+/-3.5% increase, P<0.05). Dexamethasone (1 microM) markedly reduced the constitute NGF secretion by 44.9% (7.0+/-2.1 pg/ml, P<0.001). In addition, the interleukin-1beta-stimulated NGF secretion was inhibited to approximately the same low level (8.5+/-2.5 pg/ml, P<0.001). In conclusion, we here report that human airway A549 epithelial cells are capable of producing NGF. This production is positively regulated by the pro-inflammatory interleukin-1beta, and negatively regulated by dexamethasone.

The aims of this study were to evaluate the components of biological variation of the new markers of bone turnover in patients with Paget's bone disease and to compare the results with data obtained in healthy subjects. Fifteen patients with Paget's disease in a stable period of the disease and 12 healthy premenopausal women were included for a 1 year follow-up study. Within- and between-subject biological variation, indices of individuality, and critical differences were evaluated for the following biochemical markers: in serum, total (tAP), and bone (bAP) alkaline phosphatases, procollagen type I N-terminal propeptide (PINP) and beta-carboxyterminal telopeptide of type I collagen (sCTx); in urine, hydroxyproline (Hyp), and amino (NTx) and beta-carboxyterminal (CTx) telopeptides of collagen type I. Serum markers of bone turnover showed lower biological variability than urinary markers. Within-subject biological variation was higher in pagetic patients than in healthy subjects for all serum markers. In both groups, bAP presented the lowest within-subject biological variation. In pagetic patients, all markers presented indices of individuality of <0.6, indicating their usefulness for patient monitoring. Critical differences were lower for serum markers than for urinary markers. Among pagetic patients, serum bAP and PINP showed the lowest critical differences with values close to 30%, whereas urinary CTx presented the highest critical differences (near 70%). Conversely, in healthy subjects, tAP was the marker with the lowest critical differences, being two-fold higher in pagetic patients. This study confirms the lower sensitivity of urinary markers to detect significant changes and indicates that data obtained on biological variations from healthy populations cannot always be extrapolated to pathological conditions. In addition, serum bAP and PINP seem to be the markers that best reflect a significant change in activity of Paget's disease.

The objective of this study was to evaluate the effect of surgical menopause and hormone replacement therapy (HRT) on the new biochemical markers of bone turnover. Fourteen women who had undergone surgical menopause and began HRT 3 months after surgery were recruited for a 1-year study. Results were compared with a control group of 31 healthy premenopausal women of similar age. Serum samples were obtained to determine total alkaline phosphatase, bone alkaline phosphatase, propeptides carboxy- and amino-terminal of type I procollagen (PICP, PINP), osteocalcin, tartrate-resistant acid phosphatase, and carboxy-terminal telopeptides of type I collagen (ICTP and serum CTX). Urine samples were analyzed for hydroxyproline, pyridinoline, deoxypyridinoline, alpha- and beta-carboxy-terminal telopeptides of type I collagen (alpha-CTX and beta-CTX), and amino-terminal telopeptide of type I collagen (NTX). Determinations were performed after 3 months of surgical menopause and after 3 and 9 months of HRT. All biochemical markers increased after menopause, and most of them normalized after 9 months of HRT. Serum PINP showed the highest proportion of increased values after surgery among bone formation markers (62%), as well as the highest mean percent increase (101%). Among bone resorption markers in postmenopausal women, urinary beta-CTX, alpha-CTX, NTX, and serum CTX showed the highest proportion of increased values (100%, 67%, 58%, 58%, respectively) as well as the greatest mean percent increase. They were also the markers with the most marked response to HRT. In conclusion, serum PINP is the most sensitive marker of bone formation, whereas beta-CTX is the most sensitive marker of bone resorption after surgical menopause. In addition, both markers showed the highest response after HRT.

With the experience obtained in a surgical air borne unit and the long term results in a rear zone hospital, we analyse treatments of bone and joint acute traumas in a field hospital. This injuries appear in a particular context: delayed treatments with little staff and equipment. The surgeon has to be fast with protective measures, debridement of soft tissues, bone stabilisation and vascular repair. We discuss the respective place of each treatment: amputations are dictated by the gravity of the wounds; orthopedic methods are used for the upper limb, for the lower limb they are waiting technics; external fixation stabilizes fastly bone injuries, facilitates transportation and permits delayed reconstruction technics. Indications have to be adapted to circumstances: in a surgical unit with rear evacuation possibility the dramatic choice of amputation is often avoided by external fixator; in a short time mission for civilian populations, amputations are more often used but if conservative treatment is preferred, external fixator must be widely used.

Perineo-genital wounds involving the anterior perineum or the urogenital perineum are uncommon; 1-4% of all war wounds. We report 18 cases observed in war situations. Isolated uretrogenital wounds are rarely life-threatening, but the functional prognosis is always compromised in these men whose mean age is under 30 years. Debridements should be limited and all isolated lesions should be repaired early with tight suture of the cavernous body albuginea, preservation of viable testicular and adnexal tissue (but the rate of orchidectomy is greater than 50%), and immediate suture of any wound to the urethra rather than simple alignment. In war situations, these wounds are usually caused by perforating or blast trauma. The wounds are complex, with damage to the soft tissues, sometimes involving lesions to the anal sphincter, the gluteal masses or the abdomino-pelvic structures. Laparostomy for hemostasis is justified. The risk of sepsis is high, requiring triple antibiotics, cystostomy, careful debridement, discharge drainage or possibly colostomy. Treatment of urogenital lesions is a secondary operation in these cases but must not be neglected if the mictional and sexual functions are to be preserved.

Carbonic anhydrase activity, a marker of mouse proprioceptive neurons in adult dorsal root ganglia, is first detectable in the perinatal period, increases until postnatal day 60 and remains stable in adulthood. The onset of carbonic anhydrase staining begins after the neurons have made connections with their targets suggesting that neuron-target interactions regulate carbonic anhydrase phenotype development. To examine this possibility, we first analysed carbonic anhydrase expression in mdx mice which are characterized by a massive but reversible degeneration of skeletal muscle concomitant with the carbonic anhydrase ontogenesis. Neuronal carbonic anhydrase expression in mdx mice stopped developing when the period of muscular degeneration-regeneration began. Furthermore this alteration persisted during adulthood. We then analysed carbonic anhydrase expression in fifth lumbar dorsal root ganglion of developing control mice before and after surgical procedures that might interfere with central and peripheral target influences on dorsal root ganglion neurons. Central disconnection (dorsal rhizotomy) did not affect the development of carbonic anhydrase activity. Disrupting neuron-peripheral target interactions by sciatic nerve transection or blocking muscle contraction by tenotomy stopped the development of neuronal carbonic anhydrase content. Finally, recovery was monitored following sciatic nerve crush. In adults, recovery of carbonic anhydrase activity was obtained after functional recuperation; similar manipulations during the first month of life induced irreversible alteration of the carbonic anhydrase phenotype. These results show that the development of carbonic anhydrase activity in proprioceptive neurons is regulated by neuron-muscle interactions (i.e. muscle contraction). They also provide evidence for a critical period in the development of the carbonic anhydrase phenotype. We suggest that these two mechanisms are responsible for the altered carbonic anhydrase phenotype of the dorsal root ganglion neurons in mdx mice, a model of human muscular dystrophy.

The exceptional interest in endoscopic surgery, both in laparoscopic surgery and video-assisted thoracoscopic surgery have led many teams to widen their indications. This movement has developed into a revolution in techniques demanded by patients, the public, and the medias, requiring many practicians to use these techniques more and more often and consequently to attempt very delicate operations. This "explosion" of endoscopic techniques has largely benefited from advances in equipment development (optics, video instrumentation) but has also required that operators acquire rigorous procedures for the proposed techniques. With the development of new thoracoscopic techniques for therapeutic indications, there are an unavoidable number of incidents and complications. These incidents and complications are related both to the use of instruments undoubtedly not well enough adapted to the procedures used and also to "forced" indications. We humbly recognize that a certain number of incidents are related to the necessarily inadequate experience of the operators during the "run in" period. We emphasize that video-assisted thoracoscopic surgery is a complementary technique among the available therapeutic armamentarium. We evaluated the mid and long term results of cancerology exeresis with these two techniques and underscore that morbidity and complications are rare but sometimes unacceptable. In conclusion, whatever the form of the technique used, it is an important evolution in surgery which must abide by the classical rules, in particular for indications in cancer surgery.

The military health service provided a surgery antenna during the two months of the Turquoise operation in Zaire and Rwanda. During this period, the antenna functioned as a back-up station for the French troop and the local populations subjected to various conditions: Rwanda refugees who had escaped the massacres, subjects wounded by canon shots, war wounds, surgery emergencies in the refugee population. There were 315 operations performed including 33% in children and 70% for lesions of the limbs. The activity during the mission was analyzed on the basis of strategy for surgical diagnosis and treatment under local conditions (lack of complementary examinations, limited number of personnel, disrupted families in the refugee population, no possibility for transfer, major cholera and dysentery epidemic...).

This study examined the pro- and anti-inflammatory effects of the stable prostaglandin (PG) D2 analogue, ZK 118.182 and the mechanism by which prostaglandins may exert their anti-inflammatory activity. Co-injected locally, ZK 118.182, like PGE2 and PGD2, dose-dependently increased plasma leakage induced by intradermal injection of bradykinin in rabbit skin. Infused i.v., ZK 118.182 (0.45 microgram/kg/min), a dose which did not affect systemic blood pressure, inhibited oedema formation in rabbit skin induced by the neutrophil-dependent agonists, formyl-methionyl-leucyl-phenylalanine (FMLP) and leukotriene B4 (LTB4). However, it did not modify plasma leakage induced by the neutrophil-independent mediators, bradykinin and platelet-activating factor (PAF). In contrast, neutrophil accumulation in response to LTB4 and FMLP was not affected in animals infused with ZK 118.182. In vitro, ZK 118.182, like PGE2 and PGD2 inhibited FMLP-induced superoxide anion (O2-) production by rabbit neutrophils. The compound, however, had minimal effects on O2- production induced by phorbol myristate acetate (PMA). ZK 118.182 inhibited to a small extent FMLP but not PMA-induced neutrophil adherence. These results show that depending on the route of administration, the PGD2 analogue, ZK 118.182, exhibits either pro- or anti-inflammatory effects. The anti-inflammatory effect may be related to the ability of the compound to inhibit increased microvascular permeability induced by neutrophil activation without interfering with neutrophil accumulation. This latter effect may be due to the analogue's capacity to suppress neutrophil secretion to a greater extent than neutrophil adherence.

An empirical calculation method for high-energy beam peripheral dose estimation is described. The peripheral dose has been measured for a Siemens Mevatron MX6700 (6 MV) and a Siemens Mevatron KDS (6 and 18 MV) linear accelerators. The dose distribution is parameterized for each beam energy as a function of depth, distance from the edge of the field, and field size. A simple algorithm has been developed for dose calculation up to 100 cm from the field central axes. Predictions by this algorithm are compared with measurements in an Alderson phantom.

Lipopolysaccharide can mimic many aspects of the inflammatory response to gram-negative bacteria. In rabbit and rat skin, lipopolysaccharide induces neutrophil accumulation and an increase in blood flow. Interleukin-1, tumor necrosis factor-alpha and the vasodilator, nitric oxide (NO) have been implicated in the biological responses to lipopolysaccharide and gram-negative bacteria. In the present study, we characterized the local vascular response to E. coli lipopolysaccharide in rabbit skin and investigated its dependence on de novo protein synthesis, NO, interleukin-1 and neutrophils. The local vascular response to the intradermal injection of lipopolysaccharide was determined by measuring changes in local blood flow with a laser-Doppler flowmeter. Injections of lipopolysaccharide (3, 10 and 30 micrograms/site) induced a dose-related increase in blood flow, with a maximum at 2 h. The response to 10 micrograms/site lipopolysaccharide was abolished by co-injection of actinomycin D (4 x 10(-9) mol/site), reduced by 60% by NG-nitro-L-arginine methyl ester (10(-7) mol/site) and suppressed by 82% in rabbits pretreated with dexamethasone (2 mg/kg, i.v.). However, the lipopolysaccharide-induced increase in blood flow was not affected by co-injection of recombinant human interleukin-1 receptor antagonist (7.0 x 10(-11) mol/site) or by systemic neutrophil depletion. These results demonstrate that lipopolysaccharide causes delayed vasodilatation of the rabbit cutaneous microvasculature which depends on protein synthesis and involves in part the release of NO. However, this response does not depend on interleukin-1 or neutrophils. The vasodilator effect of lipopolysaccharide may involve the expression of the inducible form of NO synthase in the vessel wall, through a mechanism independent of interleukin-1.

In anaesthetized and ventilated guinea-pigs, i.v. injection of 1 nmol/kg big endothelin-1 (big ET-1) did not evoke significant changes in pulmonary inflation pressure (PIP) and mean arterial blood pressure (MBP), whereas injection of the same dose of endothelin-1 (ET-1) induced marked and rapid bronchoconstrictor and pressor responses. Administered at the dose of 10 nmol/kg, big ET-1 provoked significant increases in PIP and MBP, which developed slowly and were long-lasting as compared to those evoked by ET-1. When big ET-1 was incubated for 45 min at 37 degrees C with alpha-chymotrypsin (2 mU/nmol) or pepsin (1 microgram/nmol) and then injected into guinea-pigs at the dose of 1 nmol/kg, marked bronchoconstrictor and pressor responses were observed, with kinetics similar to those noted after administration of the same dose of ET-1. The magnitude of the alpha-chymotrypsin- or pepsin-treated big ET-1 responses was similar to that induced by ET-1, incubated or not with the enzymes. Injected i.v. at the dose of 5 mg/kg, 5 min before the challenge, phosphoramidon almost totally inhibited the bronchoconstrictor and pressor responses induced by 10 nmol/kg big ET-1, whereas thiorphan (5 mg/kg) partially reduced the increase in PIP and exerted a minimal effect on the changes in MBP. Administered at the dose of 20 mg/kg per os, 1 h before i.v. administration of 10 nmol/kg big ET-1, enalapril maleate and captopril did not significantly alter the bronchoconstriction and the hypertensive response evoked by the peptide.(ABSTRACT TRUNCATED AT 250 WORDS)

Intravenous (i.v.) injection of endothelin in the anesthetized and ventilated guinea-pig induced a dose-dependent increase in pulmonary inflation pressure. The 1 nmol/kg dose rapidly enhanced pulmonary inflation pressure, reaching a peak at 30 s, as well as produced a marked and sustained increase in mean arterial blood pressure. A maximal increase in arterial blood pressure was observed 4 min after the injection of 1 nmol/kg endothelin and remained at a plateau for 20 min. The increase in pulmonary inflation pressure induced by endothelin was significantly enhanced by treatment of the guinea-pigs with propranolol (1 mg/kg i.v.). In contrast to what was observed in untreated guinea pigs, the injection of 1 nmol/kg endothelin in propranolol-treated animals produced within 2 min an irreversible and dramatic decrease in mean arterial blood pressure with a further decline for up to 90 min. The increase in pulmonary inflation pressure induced by 0.5 nmol/kg endothelin was also potentiated significantly in propranolol-treated guinea-pigs as compared to untreated animals. Endothelin 0.5 nmol/kg caused only a transient and non-significant increase in mean arterial blood pressure in both propranolol-treated and untreated animals. Injection of endothelin (40, 120 and 400 pmol) via the pulmonary artery into isolated guinea-pig lungs evoked significant increases in pulmonary inflation pressure and perfusion pressure accompanied by the dose-dependent release of TXB2 but, in contrast, no release of histamine. The in vitro effect of endothelin on pulmonary inflation pressure and perfusion pressure was potentiated when propranolol (1 microM) was added to the perfusion medium. These results demonstrate that the bronchopulmonary effects of endothelin are, at least in part, dissociated from the vascular action of the peptide.

The effect of serotonin (5-HT) on cyclic AMP levels in rat hypothalamic slices was age-dependent. The sensitivity of the cyclic AMP system to 5 X 10(-5) M 5-HT already existed in the foetus at 21 days of pregnancy. It reached a maximum on the 7th postnatal day and then decreased with age. In adult tissue the response was still present and was antagonized by two serotonergic antagonists (methiothepin and metergoline). When compared to the progressive increase of 5-HT level in the hypothalamus the data suggest a different evolution of serotonergic innervation and of 5-HT receptors.

By using immunoaffinity column chromatography slow (I) and fast (IIA, IIB) myosins were isolated from human (vastus lateralis) and rabbit (tibialis anterior, psoas and conoidal bundle) skeletal muscles. The peptide pattern revealed that slow (I) and fast (IIA, IIB) myosin heavy chains are quite distinct, as are those from pure slow (conoidal bundle) and fast (psoas) rabbit skeletal muscles. Unlike Billeter et al. (1981) the authors observed that fast human myosins were always associated with a small amount of slow myosin light chains. The fast myosins (IIA, IIB) from rabbit tibialis anterior muscle did not appear very distinct and contained only fast myosin light chains. These myosins were different from the IIB myosin from the psoas muscle. Ten per cent of the fibres revealed histochemically as fast IIA also reacted with an anti-slow myosin antibody. The classical histochemical techniques appear inadequate to demonstrate the existing differences among fibre types, but the monoclonal antibodies hold promise.