Search

The bactericidal activity of a pulsed fibre-optic Nd-YAP laser on various strains of oral bacteria: Prevotella nigrescens, Streptococcus sanguis, Actinomyces viscosus (i), Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans and Peptostreptococcus micros (i) was evaluated. A 200-μm optical fibre was placed in Eppendorf tubes containing the different bacterial suspensions. At an energy of 170 mJ/30 Hz, 351 pulses of 150 μs were sufficient to kill the most resistant bacteria (i). The exposure time was 28 s. The temperature rise caused by the shots were measured in vitro at the surface of the roots of two groups of 10 single-rooted teeth. One group received 350 pulses; for the other the preparation time was fixed at 28 s. The temperature rose by 25.66°C for the first group and 25.25°C for the second.

Purpose: To determine and compare the relationship between in vivo oral absorption in humans and the apparent permeability coefficients (Papp) obtained in vitro on two human intestinal epithelial cell lines, the parental Caco-2 and the TC-7 clone., Methods: Both cell lines were grown for 5-35 days on tissue culture-treated inserts. Cell monolayers were analysed for their morphology by transmission electron micrography, and for their integrity with respect to transepithelial electrical resistance, mannitol and PEG-4000 transport, and cyclosporin efflux. Papp were determined for 20 compounds exhibiting large differences in chemical structure, molecular weight, transport mechanisms, and percentage of absorption in humans., Results: The TC-7 clone exhibits morphological characteristics similar to those of the parental Caco-2 cell line, concerning apical brush border, microvilli, tight junctions and polarisation of the cell line. The TC-7 clone however appeared more homogenous in terms of cell size. Both cell lines achieved a similar monolayer integrity towards mannitol and PEG-4000. Monolayer integrity was achieved earlier for the TC-7 clone, mainly due to its shorter doubling time, i.e. 26 versus 30 hours for parental Caco-2 cells. When using cyclosporin A as a P-glycoprotein substrate, active efflux was lower in the TC-7 clone than in the parental Caco-2 cells. The Papp and mechanisms of transport (paracellular or transcellular routes, passive diffusion and active transport) were determined for 20 drugs. A relationship was established between the in vivo oral absorption in humans and Papp values, allowing to determine a threshold value for Papp of 2 10(-6) cm/sec, above for which a 100% oral absorption could be expected in humans. Both correlation curves obtained with the two cell types, were almost completely superimposable. These studies also confirmed that the dipeptide transporter is underexpressed in both cell lines., Conclusions: On the basis of morphological parameters, biochemical activity and drug transport characteristics, the TC-7 clone appeared to be a valuable alternative to the use of parental Caco-2 cells for drug absorption studies.

Antiseptic activity of five mouthrinses containing 0.10%, 0.12% and 0.20% chlorhexidine, as well as aqueous chlorhexidine solutions at the same concentrations were determined under usual conditions (advocated dilutions by the manufacturers and short contact time) and according to French Pharmacopoeia recommendations. The three aqueous solutions and two mouthrinses containing 0.12% chlorhexidine were not antiseptic according to the fixed criteria. Bactericidal activities of the different dilutions of products were tested with an appropriate micromethod against nine-bacterial species involved in periodontal disease. Efficacity of mouthrinses were variable and were not agreed with the aqueous chlorhexidine-corresponding solutions: the mouthrinse containing 0.10% chlorhexidine reached 0.20% aqueous solution efficacy, and the mouthrinses containing 0.12% chlorhexidine were generally less active than the 0.12% aqueous chlorhexidine solution. Therefore, antibacterial activity of this type of product cannot be anticipated with the sole concentration factor, excipients playing essential part in the chlorhexidine activity.

The purpose of this study was to determine if endodontic bacterial act in vitro on human gingival fibroblast functions via extracellular products. The bacteria used were Prevotella nigrescens, Capnocytophaga ochracea, Peptostreptoccocus micros and Actinobacillus actinomycetemcomitans. Supernatants were collected from bacterial cultures at the beginning of the stationary phase when their density was similar. Toxins that inhibited fibroblast proliferation were found in all culture supernatants of Gram-positive or Gram-negative bacterial strains, except for Prev. nigrescens. The cytotoxicity of A. actinomycetemcomitans supernatant was about 1000 fold higher than the others. This supernatant diluted to 1/1000 led to total fibroblast growth inhibition whereas only 25% growth inhibition was obtained with Capn. ochracea and Pept. micros diluted to 1/10. Bacterial supernatant proteolytic activity was investigated in confluent fibroblast cultures that were incubated for 48 hr with each of the supernatants diluted to 1/2 except for A. actinomycetemcomitans supernatant diluted to 1/20. Indirect immunofluorescence studies of extracellular-matrix molecules, followed by immunoelectrophoretic analysis of extracts of whole-cell layers, demonstrated that only conditioned medium of Prev. nigrescens had a proteolytic activity capable of degrading the greater part of type I collagen and fibronectin fibres in the extracellular matrix.

This study examines the controversial efficacy of chlorine and monochloramine against biofilms that differ in their extracellular polysaccharide (EPS) content. The results point out a net variability of bacterial biofilm susceptibility according to the nutrients present. Chlorine and monochloramine showed an equal biocidal activity on lactose medium-grown E. coli ATCC 10536 and glycerol-ammonium nitrate medium-grown nonmucoid Pseudomonas aeruginosa biofilms. In contrast, the effect of monochloramine is greater compared with that of chlorine on E. coli and mucoid P. aeruginosa biofilms grown in sucrose and glycerol-ammonium nitrate media, respectively. In these culture conditions, treatment with 25 mg monochloramine/L for 2 h reduced culturable cells by 4.5 logs (99.997%) for E. coli and about 3 logs (99.87%) for mucoid P. aeruginosa while the similar treatment with chlorine reduced culturable cells in these biofilms by 2.2 logs (99.4%) and 1 log (10%), respectively. The decrease of chlorine disinfection efficacy on sucrose and glycerol-ammonium nitrate medium-grown biofilms is postulated to be linked to the higher polysaccharide production observed in these media. It seems likely that monochloramine produces a high leakage of material absorbing at 260 nm from sucrose medium-grown E. coli biofilm, which could indicate its better penetration into biofilms.

Objective: To assess the motor function of the left, supposedly unaffected, limbs of patients with an acute right vascular hemiplegia., Methods: Fifteen patients with an acute vascular right hemiplegia and 16 matched healthy controls were studied. Motor function of the left limbs of each patient was evaluated on days 20 and 90 after their stroke using four validated tools (hand dynamometer, isokinetic dynamometer, finger tapping, and nine hole peg test)., Results: There was a significant impairment of motor function of the left limbs of patients at day 20 compared with controls. The impairment had recovered almost completely at day 90 after the stroke., Conclusion: These results show the bilateral cerebral representation of the human motor system and suggest the participation of ipsilateral motor pathways in recovery after a stroke.

Oral 'Ribomunyl' has been shown to increase levels of specific salivary IgA. The ability of specific salivary IgA to inhibit the adhesion of Streptococcus pneumoniae to buccal epithelial cells was investigated in vitro using 13 saliva samples from healthy volunteers who received 'Ribomunyl' therapy for 3 weeks. The S. pneumoniae strain contained in 'Ribomunyl' was [3H]thymidine-labelled and pretreated with dilutions of saliva for 1 hour at 37 degrees C. Bacterial adhesion was measured after 2 hours' contact with human oral epidermal cell monolayers at 37 degrees C under CO2. Nonadherent bacteria were washed off, and the residual radio-activity of the monolayers was compared with that of bacteria not pretreated with saliva. A significant decrease (p < 0.05) in S. pneumoniae adhesion was observed with 6 saliva samples with high levels of specific IgA. This decrease was seen at all dilutions from 1/5 to 1/1000. In contrast, no significant modification of adhesion was seen in the 7 saliva samples with unmodified levels of IgA. These data demonstrate that the increase in salivary IgA levels during 'Ribomunyl' therapy was linked with the capacity of saliva samples to specifically and efficiently inhibit adhesion of S. pneumoniae to buccal epithelial cells in vitro.

Some monoterpenes and their carbonylated products were evaluated for their antibacterial and antifungal properties. The carbonylation of tested monoterpenes was shown to increase the bacteriostatic and fungistatic activities specifically by the contact method. Concerning the killing effects, only (1R,2S,5R)-isopulegol, its carbonylated products, and (R)-carvone showed significant bactericidal activities, particularly against Enterococcus faecium and Escherichia coli above a concentration of 10 microliters/ml. A fungicidal efficiency of (1R,2S,5R)-isopulegol and (R)-carvone against Aspergillus niger was also noted. It seems that the presence of an oxygenated function in the framework increases the antimicrobial properties. However, monoterpenes were more active using a micro-atmosphere method.

Inclusion body myositis is a disease of striated skeletal muscle of unclear etiopathogenesis. Its diagnosis is difficult. Corticosteroids and immunosuppressants are of limited efficacy. Positive responses to intravenous immune globulins have recently been reported in a few patients. We used a CYBEX 6000 isokinetic dynamometer to evaluate the efficacy of intravenous immune globulin therapy in a patient with inclusion body myositis. Measurements were done at the flexors and extensors of the knee, at baseline and four and eight months after treatment initiation. A course of intravenous immune globulins (2 g per course) was given every month for five months then every two months. Isokinetic muscle strength measured at an angular speed of 180 degrees/second increased by more than 41% at both knees. As compared with muscle imaging studies (computed tomography, X-ray absorptiometry, ultrasonography, magnetic resonance imaging), isokinetic strength testing has the advantage of providing data on functional improvements under treatment.

Handicap has heavy economic implications. Pensions, whose the amount is about 127 billions of french francs, are paid, every year, to disabled persons. But the medical charges of these persons, paid by the social security, are not established, nor the wealth undoing. On the other hand, a lot of jobs are run to take care of the handicapped and many rehabilitation units and homes are devoted to them (33,000 beds) as well as adapted employment (81,000 places). The risk of dependency in the elderly has led to a deep change in the allocation of many savings. Rehabilitation cost-effective programs are contributive to reduce handicaps; significant demonstrations has been given for many common diseases as low back pain, post-stroke hemiplegia, osteoporosis.

In order to assess the sporocidal activity of chlorine and peracetic acid (PAA), alone and in combination, against a spored biofilm, the biofilms of two species (Bacillus subtilis ATCC 6633 and Bacillus megaterium ATCC 8245) were formed on inert support (tygon). A sporulation kinetic of these bacteria in biofilm was established. Sporocidal properties of chlorine and PAA were compared against free spores, spores fixed by drying and spores in biofilm. The combination of these two products was also tested. Minimal sporocidal concentrations (MSC) of the two products towards free spores were determined (contact time 5 mn). The efficacy of these MSC were evaluated in terms of contact time on adhered spores and on spores in biofilm. Chlorine and PAA exhibited an excellent sporocidal activity. The combination of PAA and chlorine, tested by checkerboard micromethod, was found to be synergistic in case of free or adhered spores. The spored biofilm showed a high resistance. The combination of these two products revealed then only an additive effect.

The study of bacterial colonization by Streptococcus mutans on dental surfaces of rat have been undertaken in vivo in gnotobiotic rat, and in vitro in an artificial mouth model, in order to validate the suitability of such a model. The study of colonization by Streptococcus mutans with time showed a similar kinetic of the monobacterial plaque formation in the two experimentations. Three phases were observed. A logarithmic phase in the earliest hours after inoculation of bacterium, followed by an exponential phase, and finally a stabilization phase of the monobacterial plaque formed in this way from the third day. Nevertheless, if the kinetic is the same, it is observed a more important colonization of dental surfaces in rat. This phenomenon was explained by the simplification of biological conditions encountered in the in vitro model. In particular, it is noticed the important saliva action. It is concluded that the in vitro model developed simulate suitably the conditions of the oral environment encountered in vivo.

The interaction type of chlorhexidine digluconate/chlorocresol association (foaming solution DC 102/1, Laboratoires Pierre Fabre Médicament) have been studied according to the chess-board method, on microplate, by determining MBC (Minimal Bactericidal Concentrations) (or MFC (Minimal Fungicidal Concentrations)) adjusted to T 72-150 AFNOR norm (dilution-neutralization, contact 5 mn) and computation of FBC (or FFC) Index. Trials were carried out against 18 hospital strains (Staphylococcus epidermidis, Staphylococcus aureus, Propionibacterium acnes, Candida albicans) and against 4 strains of the AF-NOR norm. MBC of chlorhexidine, against Staphylococci were included between 6.25 and 25 micrograms/ml, and between 25 and 200 micrograms/ml against the others strains. MBC of chlorocresol were included between 800 and 3,200 micrograms/ml. Against the 22 tested strains, 18 synergistic interactions (FBC Index < or = 0.75) were observed, with 4 to 8 reducing factor for chlorhexidine, and > or = 2 for chlorocresol. No antagonism was noted (maximal FBC Index = 1).

Objective: To determine the value of antenatal diagnosis of congenital toxoplasmosis by ultrasound guided aspiration of cord blood for testing., Material: This is a prospective study of 176 cases. As well as obtaining fetal blood and amniotic fluid the searched for specific IgM and A as well as culturing for the parasites on human fibroblasts and inoculation of mice, as well as researching them for non-specific signs of fetal infection. 149 children were able to be followed up one year after birth., Results: 15% of the children (22/149) were infected with toxoplasmosis. 11 out of these were diagnosed positive antenatally. For the 11 others the diagnosis of fetal infection could only be made after birth, but the non-specific signs made it possible to expect early that they had been contaminated. 59% (13/22) had latent toxoplasmosis which only showed up after a mean interval of 34 months after birth. 41% (9/22) had clinical and/or paraclinical signs of toxoplasmosis (mainly unilateral non-macular chorioretinitis and intracranial calcifications) but they are well after a follow-up period averaging 30 months., Commentary: Ultrasound alone, when it shows up fetal abnormalities, can make the diagnosis of the severity of the condition. The role of taking fetal specimens is to make clear those infants that are infected because of specific signs, and to find those fetuses which are at high risk because of non-specific signs in order to improve the management of the cases. This development has made it possible to avoid carrying out a large number of unnecessary terminations of pregnancy and has resulted in the birth of affected infants that had no functional sequelae from the infection.

The sporocidal properties of peracetic acid, hydrogen peroxide, chlorine, and formaldehyde were compared in vitro using a dilution-neutralization micromethod. A combination of peracetic acid and hydrogen peroxide was also tested to assess their interactions. The activities of these agents, which are widely used as disinfectants, were evaluated against Bacillus spore isolates found on stored membranes and collection cultures. Peracetic acid and chlorine exhibited an excellent antimicrobial activity, with a destruction of 10(5) spores/mL after 5 min of contact. Generally the effects of the biocides tested were time dependent. The sporocidal activities of hydrogen peroxide and formaldehyde were the lowest. The combination of peracetic acid and hydrogen peroxide, tested by a checkerboard micromethod, was found to be synergistic. The minimal sporocidal concentration (MSC) was established in terms of time for each biocide. The lowest MSC values for peracetic acid, hydrogen peroxide, chlorine, and formaldehyde were 168-336 ppm (1-2 h of contact), 5625-11250 ppm (5-7 h), 168-336 ppm (2-3 h), and 1875-3750 ppm (5-30 min), respectively. The MSC of a biocide combination of peracetic acid and hydrogen peroxide showed that synergy was maintained with increasing contact time and that the MSC could be reduced by two to eight times when compared with those of the biocides alone. Optimal concentrations and contact times of those chemicals that were promising in vitro were then tested for their ability to disinfect ultrafiltration membranes. The sporocidal activities of peroxide compounds and chlorine were confirmed and the synergism between peracetic acid and hydrogen peroxide was also maintained.(ABSTRACT TRUNCATED AT 250 WORDS)

The bactericidal properties of peracetic acid, hydrogen peroxide, chlorine, and formaldehyde were compared in vitro using a rapid micromethod. A combination of peracetic acid and hydrogen peroxide was also tested to assess interactions. The activities of these agents, which are widely used as disinfectants, were evaluated against water isolates and culture collection strains. Peracetic acid and chlorine exhibited an excellent antimicrobial activity, with a relatively rapid destruction of 10(5) bacteria/mL. The time-dependent bactericidal activities of hydrogen peroxide and formaldehyde were the lowest. The combination of peracetic acid and hydrogen peroxide, tested by a checkerboard micromethod, was found to be synergistic. The minimal bactericidal concentration was established in terms of time for a given mixture of peracetic acid and hydrogen peroxide. Determination of bactericidal concentrations showed that synergy was maintained with increasing contact time. Concentrations for minimal times of treatment by chemicals that provided interesting activities in vitro were tested for disinfection of ultrafiltration membranes. The bactericidal activities of peroxygen compounds were confirmed and synergism was maintained in working conditions. Chlorine showed a loss of efficacy when used on membranes.

Treatment of healthy volunteers by Ribomunyl, whether or not in association with in vitro antibiotics (amoxicillin or josamycin), has been earlier demonstrated to be an efficient stimulant of PMN functions (adhesion and migration). This second double-blind study versus placebo was performed on 17 patients with acute respiratory infections (placebo group: eight subjects; Ribomunyl group: nine subjects). Ribomunyl treatment (four days) associated with antibiotherapy (amoxicillin) induced a significant increase of PMN adhesion (p = 0.014) with no significant effect of the placebo (p = 0.30) and no significant difference between the initial level of PMN adhesion of the two groups (placebo-Ribomunyl).

Bactericidal activities of five mouthrinses containing cetylpyridinium chloride, hexetidine or chlorhexidine have been tested in vitro, against the main microorganisms involved in buccal affections. Mouthrinses containing hexetidine or chlorhexidine are effective, but chlorhexidine activity appears more extensive and homogeneous.

The in vivo effect of immunostimulant treatment, bacterial ribosomes together with membranal proteoglycans (three tablets and three sprays daily during 4 days) in combination or not with in vitro amoxicillin or josamycin (range 5-50 micrograms/ml), has been studied on three related functions of polymorphonuclear cells (PMN) isolated from human blood: adhesion, spontaneous and oriented migration. The immunostimulant treatment always induces an increase of the three parameters. A positive effect of high concentrations of amoxicillin could be also observed on adhesion and gives rise to a great additional impact by associating it with immunostimulant treatment (control: 8.26 PMN/field; assay: 51.55 PMN/field). Spontaneous and oriented migration are not very altered by in vitro antibiotics. A very significant decrease of chemotaxis has been only observed with 50 microgram/ml of josamycin. However, the immunostimulant treatment compensates for this negative effect. The real increase in PMN activation produced by the immunostimulant treatment might extend its indications beyond prevention during antibiotherapy, for example in the acute phase of respiratory infections.

Studies were conducted to assess the penetration of 1% ciclopiroxolamine cream, establishing the concentrations of the antimycotic compound in different layers of the stratum corneum with two skin models. Results of in vitro studies using skin from domestic pigs indicate that ciclopiroxolamine has the ability to penetrate fast into the epidermis, by inhibiting and killing inoculated Trichophyton mentagrophytes. In vivo investigation of the stratum corneum has been performed in healthy human volunteers by 20 strippings collected in four layers. Fungicidal concentrations of ciclopiroxolamine were determined after extraction from the strippings. These studies demonstrate that the concentrations reached levels which are sufficient to inhibit and kill pathogenic fungi.

This report presents original methods to assess the bioavailability of an antifungal drug from a varnish preparation in finger nails. For the studies with human volunteers a ciclopirox 8% nail lacquer was used to determine its efficacy in the treatment of onychomycoses. In vivo studies were performed on the fingernails of healthy volunteers by determining the total amount of ciclopirox penetrated per milligram of nail and the partition of the drug in the plate of the nails (technically divided into four layers). Ciclopirox concentrations were evaluated by measuring the inhibition of Candida pseudotropicalis growth in vitro. The ciclopirox concentration after 30 days treatment was determined as 3.35 +/- 0.82 micrograms/mg nail material. This is a sufficient amount to kill the fungal pathogens. In addition, in vitro penetration experiments were carried out with excised pig skin. Lacquer formulations from 0.5 to 8% were used to inhibit the growth of Trichophyton mentagrophytes. Formulations from 2 to 8% led to a strong to total inhibition of the dermatophyte after 30 min treatment time.

The authors demonstrated in the urine of certain patients a peptide form of hydroxyproline and of glutamic acid. This peptide was found in patients with Paget's disease who presented clinical and laboratory signs of an evolutive episode and in other patients who presented restructuration of bone of a radiologicaly type. This peptide was one of the factors determining the increase in the total hydroxyprolinuria. The demonstration of the peptide provokes discussion as to its origin, and also of the possibility of using it as a biochemical parameter.

Bone imaging of the lower pelvis often is impaired by the radioactivity of the bladder. The caudal view produces an image that clearly distinguishes the bladder from the bones. Thus, it is helpful in patients with bony lesions of the lower and anterior pelvis. The caudal view examination is completed by a backward tilting of the camera head that clarifies this distinction.

Rheometric studies of 34 synovial fluids done using a rheometer with a cone and stage (Shirley-Ferranti type) showed that arthrotic synovial fluids had pseudoplastic characteristics (non-Newtonian) but in inflammatory rheumatisms, the characteristics index rises, the consistency decreases and the fluid tends to loose its pseudoplastic properties and to become Newtonian. Radioisotope synoviorthosis seems capable of restoring to a certain extent and in certain cases the rheometric characteristics of the pseudoplastic properties.

The authors report the main data of a series collected on a rheumatology unit where the bony signs were most obvious. Survival was comparable with that of large series in the literature. The prognosis seems to be linked to numerous factors therapeutic and etiologic (age, sex, type of monoclonal immunoglobulin) visceral and blood involvement. The diagnosis is now made earlier, but the differential diagnosis includes the other monoclonal immunoglobulin gammapathies.

The authors looked for Australia antigen in a population of 578 rheumatic patients, 300 of whom were polyarthritic, by electrosyneresis and complement fixation methods. Australia antigen was found in 26 patients, and anti-Australia antibodies in 33 patients. Most of these patients were suffering from rheumatoid polyarthritis--22 presented hepatic disturbance, and 28 had undergone surgical operations, blood transfusions, and repeated hospitalization. The presence of Australia antigen did not in any case appear to play a role in the development of the lesions, apart from the occurrence of signs of hepatic lesions, but appeared to be an indicator of a form of hospitalization.

In a number of cases of true rheumatoid arthritis, it is not possible to demonstrate the presence of 19 S "heavy" rheumatoid factors by the Waaler-Rose and globulin latex techniques. However, in some of them, 7 S rheumatoid factors are suspected. Three techniques for the detection of these "light" rheumatoid factors are described and critically evaluated. The authors report their own experience of the immuno-absorption and indirect immunofluorescence technique performed on 156 sera from RA patients. Immuno-absorption is not felt to be a reliable technique on several grounds. Indirect immunofluorescence is of value only in the diagnosis of seronegative rheumatoid arthritis where it provides information in addition to that offered by classical techniques. It is positive in 53.3% of seronegative rheumatoid arthritis sera.

In Toulouse, various epidemiological works and biological results regarding toxoplasma infection permitted us to study immunity in pregnant women. 66 to 70% are immunized. Incidence of acquired toxoplasmosis is 1 to 2 for 1,000 pregnancies. Carefully planned, regionalized programs with obstetricians and pediatricians are realized to prevent congenital toxoplasmosis. Epidemiological studies may be realized to estimate the prevalence and the incidence of congenital toxoplasmosis before such programs can be recommended on a national scale in tropical area.

In making a comparative study of different parameters in the examination of synovial fluid (rheumatoid factors, ragocytes, leucocytes, synovial complement, immunoglobulins) the authors show that rheumatoid fluid has characteristics that make differentiation from other inflammatory arthropathies possible on a statistical basis, thanks to the test for the homogeneity of the means. The presence of these characteristics seems to constitute a diagnostic argument which can be measured by mathematical methods.