High prevalence of cfxA beta-lactamase in aminopenicillin-resistant Prevotella strains isolated from periodontal pockets.

This prospective study was designed to investigate amoxicillin-resistant oral anaerobes, and to identify their beta-lactamase-encoding genes. Three subgingival bacterial samples were collected from 12 patients suffering from periodontitis. One to seven beta-lactamase-producing strains were obtained from each patient, mostly belonging to the Prevotella genus (Bacteroides eggerthii, 2/35 strains; Prevotella sp., 33/35 strains). PCR assays were used to detect cfxA and cepA/cblA, the genes encoding class A/group2e beta-lactamases previously described in the Bacteroides fragilis group. The present investigation confirmed the role of Prevotella species as beta-lactamase producers in periodontal pockets. Additionally, this PCR screening showed (1): the high prevalence of CfxA beta-lactamase production by aminopenicillin-resistant Prevotella (32/33: 97.0% positive strains) vs. cepA/cblA (1/33: 3.0% positive strains), and (2) the presence of cfxA in the periodontal reservoir in the absence of antimicrobial therapy during the previous 6 months.

Resistance profile survey of 50 periodontal strains of Actinobacillus actinomyectomcomitans.

BACKGROUND: Antibiotic resistance has been increasingly described among bacterial species colonizing periodontal pockets, particularly in Prevotella and Porphyromonas spp. strains producing beta-lactamases, and frequently associated with resistance to tetracycline and erythromycin. These resistance genes may be carried on motile genetic elements, or transposons, capable of interspecies and intergeneric transmission among bacterial strains colonizing a same ecological niche. The aim of this prospective study was to determine the resistance profile of Actinobacillus actinomycetemcomitans and the prevalence of A. actinomycetemcomitans strains producing beta-lactamases in periodontal pockets. METHODS: Fifty strains of A. actinomycetemcomitans were isolated from 42 patients with adult periodontitis. No patient had periodontal or antibiotic therapy in the previous 6 months. Bacterial samples were collected from periodontal pockets > or =5 mm, appropriately diluted, inoculated onto selective medium (chocolate blood agar with bacitracin 75 microg/ml and vancomycin 5 microm/ml) and incubated for 5 days at 37 degrees C in air with 5% CO2. After conventional identification, susceptibility testing to 11 antibiotics was performed by the broth dilution method, in trypticase soy broth supplemented with yeast extract, hemin, and 0.1% NaHCO3 to maintain microaerophilic conditions in the microtitration plate wells by CO2 formation. RESULTS: No strain demonstrated resistance to amoxicillin, amoxicillin-clavulanic acid combination, pristinamycin, or ciprofloxacin at the breakpoint, but 40% of the strains were slightly resistant to penicillin G, and 4% were resistant to erythromycin, 90% to spiramycin, 18% to clarythromycin, 4% to tetracycline, 72% to metronidazole, and 12% to ornidazole. Amoxicillin, followed by tetracycline and erythromycin, was the most effective antibiotic on A. actinomycetemcomitans. The phenotypic research of a beta-lactamase was negative for all the strains tested. CONCLUSIONS: In this work, most A. actinomycetemcomitans strains were resistant to metronidazole, but the amoxicillin-metronidazole association may be of interest against subgingival anaerobic and capnophilic mixed flora. Pristinamycin and ciprofloxacin appeared as effective alternative monotherapies against A. actinomycetemcomitans. The threat of beta-lactam antibiotic resistance related to beta-lactamase production is currently not a problem with A. actinomycetemcomitans as it has been reported in oral anaerobes.

Comparative study of physical properties of three suture materials: silk, e-PTFE (Gore-Tex), and PLA/PGA (Vicryl).

The aim of this in-vitro study was to compare the physical properties of three suture materials used in periodontal surgery: silk, expanded polytetrafluoroethylene (e-PTFE), and polylactic acid/polyglycolic and (PLA/PGA). Five physical tests were carried out on each of the three suture materials: strain to failure, tensile strength, knot tensile strength, knot slippage, and capillarity. For each test, 30 samples of each suture material were used. In all cases, the statistical results showed that the e-PTFE and the PLA/PGA threads were superior.

Prevalence of beta-lactamase-producing strains among 149 anaerobic gram-negative rods isolated from periodontal pockets.

In a prospective study, 47 adults presenting a rapidly progressive periodontitis were selected in order to evaluate the prevalence of beta-lactamase-producing strains among oral anaerobic gram-negative rods. Predominant anaerobes were identified from two of the deepest periodontal pockets. beta-Lactamase-positive strains fulfilled to at least two of three criteria: positive nitrocefin test, penicillin Etest minimal inhibitory concentration > 1 microgram/ml, and disk diffusion synergy between amoxycillin and clavulanic acid > 10 mm. At least one beta-lactamase-producing strain was found in 53.2% of patients and 39.4% of the periodontal pockets investigated. Prominent beta-lactamase-positive species were Prevotella buccae and Prevotella intermedia (respectively 16 of 38: 42% and 18 of 52: 35% positive strains), followed by Prevotella bivia, Prevotella disiens, Prevotella denticola and Fusobacterium nucleatum (respectively 1 of 6: 17%, 1 of 10: 10%, 1 of 10: 10%, and 1 of 13: 8% positive strains). No beta-lactamase producer could be evidenced in Porphyromonas gingivalis (10 strains tested). All the beta-lactamase-positive strains with the nitrocefin test had penicillin minimal inhibitory concentrations > 1 microgram/ml with the Etest, and a strong synergy between amoxicillin and clavulanic acid was always observed.

Effects of combined topical metronidazole and mechanical treatment on the subgingival flora in deep periodontal pockets in cuspids and bicuspids.

The Effect on the subgingival microflora of a single topical administration of a 95% collagen and 5% metronidazole device in combination with debridement was investigated in 30 adult periodontitis patients in comparison with mechanical treatment alone. For each patient, plaque samples from test and control sites in cuspids and bicuspids were collected for culture and enumeration of total anaerobically cultivable bacteria (TA), black-pigmented anaerobes (BPA), and Actinobacillus actinomycetemcomitans (Aa). Spirochetes and fusiforms were quantified by direct microscopic examination after Giemsa staining. A decrease was observed for all parameters, and a significant difference in comparison with the control group was found for fusiforms. After treatment, a lower number of Aa positive sites were observed in the test group (13/25). These results show that a single application of topical metronidazole seems to be effective as adjunctive antimicrobial treatment in adult periodontitis.

[Migration and family roles: demographic measurement and cultural contexts]. / Migrations et roles familiaux: mesure demographique et contextes culturels.

"Demographers explain the fact that women are heads of households in the countries of origin by the shortage of men created by labour migration (the so-called sex-ratio argument). Empirical testing using census or survey data pertaining to a large number of countries proves disappointing. No significant statistical correlation can be established between sex ratios and various characteristics of the households. In order to understand the failure of the methodology used, one must shift from demography to the sociology of migrations and take into account the cultural contexts, and more specifically roles and statuses of women, as is shown in the case of the Caribbean and of the Dogon, one of the ethnic groups in Mali." (SUMMARY IN ENG AND SPA)

Topical metronidazole as an adjunct to subgingival debridement in the treatment of chronic periodontitis.

The purpose of this study was to evaluate the clinical effects of a single application of a 5% metronidazole collagen device in periodontal pockets deeper than 5 mm, in association with debridement and without reinforcement of home care and hygiene as practiced by the patient at any time. Pocket depth, attachment level, bleeding on probing, gingival index and plaque index were assessed at baseline, and on days 15, 30 and 90. Analysis of data from 28 patients indicated that both debridement and metronidazole therapy decreased pocket depth, bleeding on probing and gingival index, but results were significantly better with metronidazole. These results indicate that topical metronidazole provides an effective adjunctive treatment of advanced periodontitis.

[The migration policy of the Ivory Coast]. / La politique migratoire de la Cote-d'Ivoire.

PIP: Migration policies adopted by the Ivory Coast at independence were essentially a continuation of colonial policies aimed at providing manpower for the coffee and cacao plantations of the south, whose exports were to form the basis of the national development strategy. Instead of forced labor, the government facilitated installation of migrants in agricultural areas by means of laws assuring their access to lands not currently in use. Massive immigration of workers resulted in an age and sex distribution favorable to the needs of the plantation economy. The concentration of development efforts in the forest zone of the south, including Abidjan, encouraged thousands of workers from the savannah to migrate south in search of higher incomes and better living conditions. Bilateral accords with the former Upper Volta and with France and multilateral accords with the Economic Community of the West African states regulated the migratory movement. The Ivory Coast's migration policy succeeded in populating the forest zone and permitted the Ivory Coast to construct a powerful economy. But the policy produced sometimes violent opposition among natives overwhelmed by foreigners in search of lands. The loss of labor force in the savannah threatened the nation's food supply and demographic balance. In the forest zone itself, many of the immigrant workers left the plantations to seek greater success in the cities, swelling the ranks of the urban unemployed and leaving much of the rural area short of labor. In prosperous times, when prices for southern goods were high, the system worked reasonably well. When economic conditions worsened, the inefficiency of the policy became clear. At those times the international conventions failed to control the influx because of the conflicting interests of the countries. Ethnic and regional tensions mounted, the rural exodus continued despite attempts to encourage regional development, and conflicts over land tenure intensified.^ieng

[Relationship between vital pulp and deep periodontal pockets]. / Relations entre pulpe vitale et tissus parodontaux profonds.

From clinical observation, the relationships between vital pulp and deep periodontal pockets are discussed. The bone healing of infra periodontal pocket is not performed after periodontal treatment, but after pulpectomy.

[Nuptiality and fertility in Senegal]. / Nuptialite et fecondite au Senegal.

PIP: Data from Senegal's 1978 World Fertility Survey were used to demonstrate the decisive role of intermediate variables in the determination of general and marital fertility rates. Senegal's total fertility rate of 7.2 in 1974-78 indicates a high level of fertility which, moreover, appears to have changed little over time. Marital fertility is slightly higher than general fertility: married women had an average of 4.03 live births, vs. 3.53 for all women. A seemingly significant fertility differential by maternal educational status amounting to 1.34 child disappears when age and age at marriage are controlled. Age at marriage is a significant influence on fertility in the 1st 5 years of marriage, with fertility lower among women aged 15 or under at marriage. Abortion is a marginal practice in Senegal, and contraception is not widespread. 10% of ever married women reported having ever used a traditional method, and 1% a modern method. At the time of the survey only .5% used a modern method. Few significant differentials were noted in abortion or contraception by rural or urban residence. A slightly longer period of breastfeeding in rural areas (19.1 months vs. 17.6 months in urban areas) probably accounts for more of the slight rural-urban fertility differential than does abortion or contraception. Nuptiality in Senegal is early and intense, but is less stable than in most other African countries. The average age at 1st marriage of women aged 20-29 years was 16.4 for urban women, 15.6 for rural women, 17.0 for literate women, 15.7 for illiterate women, 16.0 for Wolofs, 15.1 for Poulars, 15.5 for Mandingos, 16.5 for Serers, 17.0 for Diolas, and 15.8 for the entire sample. Differences in age at marriage by rural or urban residence and women's educational level were more marked in younger cohorts. 95.6% of women aged 25-29 and 99.8% of those aged 30-34 at the time of the survey were already married. Age at marriage influences the propensity to divorce. 23.6% of marriages of women married at under 20 years vs. 19.1% of marriages of women over 20 ended in divorce. But 89% of divorced women subsequently remarried. Education, residence, and ethnic group also influenced the risk of divorce. 33% of Poular women, 27% of urban women, 27% of literate women, and 23% of Serer women ended their 1st unions in divorce. Wolof, Diola, and illiterate women had an average tendency to divorce, with 19% in each group terminating their 1st unions. 17% or rural women and 11% of Mandingo women divorced. Polygamy is widespread in Senegal. 48% of married women and 32% of married men are in polygamous unions. Senegal Fertility Survey data were limited to the current union, preventing a profound study of the interrelations between fertility and polygamy. But available data suggest that there are no fertility differences between monogamous and polygamous women either in the early years of marriage or overall. But divorce is much more likely for women infertile in the 1st years of marriage.^ieng

[Experimental study of a metronidazole gel inserted in periodontal pockets]. / Etude expérimentale d'un gel de metronidazole inséré dans des poches parodontales.

The aim of this study was to evaluate the effects of a gel containing 4% metronidazole and collagen in periodontal pockets deeper than 4 mm. The treatment was utilized in 10 subjects with pocketing in the premolar-molar regions. The experimental design was as follows: one quadrant was treated with scaling and root planning (S), one with the metronidazole gel (M), one with scaling, root planning and metronidazole gel (S & M), and the last quadrant remained untreated. Pocket depths, gingival index (GI), sulcular bleeding index (SBI) and plaque indices were recorded at 7, 14 and 30 days after the experiment began. Significant improvement of the parameters studied was noted in the S & M quadrants.

Quantification of T6+ and HLA/DR+ Langerhans cells in normal and inflamed human gingiva.

Langerhans cells are dendritic non epithelial cells found in the gingiva. The latest research in immunohistochemistry suggests that they may play an important role in the cellular immune response. The purpose of this quantitative study was to evaluate the number of Langerhans cells in association with gingival inflammation and the use of monoclonal antibodies reacting with two different antigens: T6 and HLA-DR, present on the cell membrane. Results indicate that Langerhans cells are mostly T6+; but HLA-DR appears as a good functional marker. Langerhans cells may play an important role in the cellular immune response to bacterial antigens in moderate inflammation of the gingiva.

[The role of cellular immunity in gingival inflammation through a study of the cells of Langerhans]. / La place de l'immunité de type cellulaire dans l'inflammation gingivale à travers l'étude des cellules de Langerhans.

The purpose of this semiquantitative study was to evaluate the number of Langerhans cells in correlation with gingival inflammation and the use of two antisera: anti-T6 and anti-HLA/DR reacting with two different membrane antigens. Results indicate that HLA/DR is a better functional marker, and that the number of Langerhans cells is higher in the moderate inflammation of the gingiva (G.I. 1 to 2).