Experimental study on the quasi-steady approximation of glottal flows

To examine the quasi-steady approximation of the glottal flow, widely used in the modeling of vocal fold oscillations, intraglottal pressure distributions were measured in a scaled-up static vocal fold model under time-varying flow conditions. The left and right vocal folds were slightly open and set to a symmetric and oblique configuration with a divergence angle. To realize time-varying flow conditions, the flow rate was sinusoidally modulated with a frequency of 2 and 10 Hz, which correspond to 112.5 and 562.5 Hz, respectively, in real life. Measurements of the intraglottal pressures under both steady and time-varying flows revealed that the pressure profiles of the time-varying flow conditions are non-distinguishable from those of the steady flow conditions as far as they have the same subglottal pressure as an input pressure. The air-jet separation point was also non-distinguishable between the steady and the time-varying flow conditions. Our study therefore suggests that the time-varying glottal flow can be approximated as a series of steady flow states with a matching subglottal pressure in the range of normal vocalization frequencies. Since the glottal closure was not taken into account in the present experiment, our argument is valid except for such a critical situation.

Mapping co-benefits for carbon storage and biodiversity to inform conservation policy and action

Integrated high-resolution maps of carbon stocks and biodiversity that identify areas of potential co-benefits for climate change mitigation and biodiversity conservation can help facilitate the implementation of global climate and biodiversity commitments at local levels. However, the multi-dimensional nature of biodiversity presents a major challenge for understanding, mapping and communicating where and how biodiversity benefits coincide with climate benefits. A new integrated approach to biodiversity is therefore needed. Here, we (a) present a new high-resolution map of global above- and below-ground carbon stored in biomass and soil, (b) quantify biodiversity values using two complementary indices (BIp and BIr) representing proactive and reactive approaches to conservation, and (c) examine patterns of carbon-biodiversity overlap by identifying 'hotspots' (20% highest values for both aspects). Our indices integrate local diversity and ecosystem intactness, as well as regional ecosystem intactness across the broader area supporting a similar natural assemblage of species to the location of interest. The western Amazon Basin, Central Africa and Southeast Asia capture the last strongholds of highest local biodiversity and ecosystem intactness worldwide, while the last refuges for unique biological communities whose habitats have been greatly reduced are mostly found in the tropical Andes and central Sundaland. There is 38 and 5% overlap in carbon and biodiversity hotspots, for proactive and reactive conservation, respectively. Alarmingly, only around 12 and 21% of these proactive and reactive hotspot areas, respectively, are formally protected. This highlights that a coupled approach is urgently needed to help achieve both climate and biodiversity global targets. This would involve (1) restoring and conserving unprotected, degraded ecosystems, particularly in the Neotropics and Indomalaya, and (2) retaining the remaining strongholds of intactness. This article is part of the theme issue 'Climate change and ecosystems: threats, opportunities and solutions'.

Influence of level difference due to vocal folds angular asymmetry on auto-oscillating replicas

Dysphonia is often caused by level difference between left and right vocal folds, which are positioned on different angles with respect to the transverse plane, resulting in angular asymmetry. Unilateral vocal fold paralysis may cause such angular asymmetry. In this case, the normal vocal fold is located on the transverse plane, whereas the paralyzed vocal fold is rotated in the sagittal plane as its posterior edge is moved up to the superior direction. The effect of such angular asymmetry (up to 25°) between the left and right vocal fold on the auto-oscillation is experimentally studied using mechanical replicas. For all replicas, it is observed that, as full contact between vocal folds is lost, increase of angular asymmetry results in a decrease of the signal-to-noise ratio, an increase of the total harmonic distortion rate, and an increase of the oscillation threshold pressure. These general tendencies are in agreement with clinical findings reported for vertical level difference during phonation. In analogy to the preceding experimental study in which vocal folds are spaced in parallel with a vertical trade-off, a formula is proposed to describe the oscillation threshold as a function of angular asymmetry.

Quantifying the auto-oscillation complexity following water spraying with interest for phonation

Human voiced sound production or phonation is the result of a fluid-structure instability in the larynx leading to vocal folds auto-oscillation. In this paper, the effect of surface hydration following water spraying (0 up to 5 ml) on an ongoing auto-oscillation is studied experimentally using different mechanical deformable vocal folds replicas. The complexity of the oscillation is quantified on the upstream pressure by a phase space recurrence and complexity analysis. It is shown that: (1) the ratio of the degree of determinism to the recurrence rate of the phase space states γ and (2) estimated correlation dimension D_{2} are suitable parameters to grasp the effect of hydration on the oscillation pattern. The oscillation regime after hydration can either remain deterministic or approach a chaotic regime depending on initial conditions prior to water spraying, such as elasticity, glottal aperture, as well as oscillation complexity.

Outbreak of Colonization and Infection With Vancomycin-ResistantEnterococcus faeciumin a French University Hospital

An outbreak of infection with vancomycin-resistantEnterococcus faeciumoccurred at Hôtel-Dieu Hospital (Clermont-Ferrand, France). A case-control study was performed in the infectious diseases and hematology units of the hospital. Urinary catheter use (odds ratio [OR], 12 [95% confidence interval {CI}, 1.5-90];P<.02), prior exposure to a third-generation cephalosporin (OR, 22 [95% CI, 3-152];P= .002), and prior exposure to antianaerobials (OR, 11 [95% CI, 1.5-88];P<.02) were independently predictive of vancomycin-resistantEnterococcus faeciumcarriage.

[Epidemiology of Streptococcus pyogenes invasive diseases in France (2007-2011)]

Group A Streptococcus (GAS) is a human pathogen responsible for a wide range of clinical manifestations. An increase of GAS invasive infections has been described since the mid 1980s. To study the French epidemiology of invasive infections (i) we characterized all GAS invasive strains received at the French National Reference Center for streptococci (CNR-Strep) between 2007 and 2011; (ii) we analyzed the epidemiological data on the corresponding strains. For each strain, emm genotype, superantigen genes and antibiotics susceptibility were determined. Among the 2 603 non redundant invasive GAS strains, 65.1 % (n=1 695) were isolated from blood culture. A streptococcal toxic shock syndrome (STSS) was described in 16.4 % (n=428) of cases, mostly associated with necrotizing fasciitis (NF), pleuropulmonary or osteoarticular infections (p ≤0.001). The case fatality rate was 10.6 %. A total of 102 different emm genotypes were identified. Three emm genotypes predominated, reaching nearly 60 % of the strains: emm 1 (26.7 %), emm 28 (16.4 %), and emm 89 (12.8 %). The proportion of each emm genotype varied according to the year and the age of patients. Among those < 15 years old, the three main genotypes were emm 1 (36.8 %), emm 12 (12.9 %) and emm 4 (9.5 %). The distribution of superantigen genes (SpeA, SpeC and Ssa) was restricted to several emm genotypes. Between 2007 and 2011, the rate of macrolides resistant GAS strains decreased from 7.8 to 5.5 %. emm 1 strains are still the most common especially in most severe clinical manifestations including STSS and NF.

Epidemiological markers of Streptococcus pyogenes strains in Tunisia

To further understand the epidemiology of Streptococcus pyogenes or group A streptococcus (GAS) infections in Tunisia, phenotypic and genomic markers of GAS isolates, including antibiotic susceptibility, biotypes, T and emm types and toxin gene profiles, have been characterized. A total of 103 isolates, collected between 2000 and 2006, were investigated; 47 were recovered from invasive infections, and 56 from non-invasive infections. Rates of resistance to tetracycline, erythromycin, clindamycin and rifampin were 70.8%, 4.8%, 4.8% and 0.9%, respectively. High levels of resistance to streptomycin and kanamycin were observed in 1.9% and 4.8% of isolates, respectively. Biotype 3 was most common. Twenty different T patterns were observed, with a predominance of T3/13/B3264, and 38 different emm types. In both invasive and non-invasive isolates, emm118 (9.7%), emm42 (8.7%), emm1 (7.8%), st432 (6.8%), emm28 (5.8%) and emm76 (5.8%) were the most prevalent types; emm1, emm76 and emm18 were mainly observed among invasive infections, whereas emm118 (12.5%), emm42 (10.7%) and emm28 (8.9%) were predominant among non-invasive infections. The speB gene was detected in all isolates, but there were variable frequencies of speA, speC and ssa (20.3%, 32% and 25.2% respectively). Significant associations of emm1, emm18 and emm3 with speA and of emm4 and st432 with ssa were found. This first report from Tunisia revealed a unique emm distribution of GAS that differs from those of other regions. This information on the distribution of such emm types will be useful for the development of an appropriate vaccine in a country where the incidence of rheumatic fever remains high.

Reduced susceptibility to amoxicillin of oral streptococci following amoxicillin exposure

As antibiotic pressure often triggers bacterial resistance, the use of short-duration therapies is increasingly recommended. The objective of the present study was to evaluate both the clinical efficiency and the impact on oral streptococci of a 3 day versus a 7 day amoxicillin therapy for odontogenic infection requiring tooth extraction. On day 0, patients were randomly assigned to a 3 day or 7 day amoxicillin treatment. The tooth was extracted on day 2 and the post-operative follow-up was carried out on day 9. Oral flora was collected on days 0, 9 and 30, and the susceptibility of the streptococci to amoxicillin was determined. The results showed that treatment with amoxicillin for 3 or 7 days had a similar clinical efficiency, and also induced similar selection of oral streptococci with reduced susceptibility to amoxicillin, suggesting that the selection of strains with reduced susceptibility to amoxicillin is a rapid phenomenon, appearing even with short-duration therapies.

A family outbreak due to an emm-type 11 multiresistant strain of Streptococcus pyogenes

Four cases of Streptococcus pyogenes infection due to an emm-type 11 strain, including one with a fatal outcome, occurred within a seven-member family. All strains shared biotype 5, pyrogenic exotoxin genes speB and speC, and resistance to kanamycin, tetracycline, macrolides and lincosamides. The identity of SmaI pulsed-field gel electrophoresis patterns confirmed their clonal origin. This highlights the ability of S. pyogenes to spread rapidly among family members. This first report of a family outbreak due to emm11 S. pyogenes reinforces the importance of surveillance of close family contacts of individuals with invasive streptococcal disease, and provides further support for antibiotic prophylaxis among the elderly.

[Interest of peri-operative immunonutrition in head and neck cancers]

OBJECTIVE

Authors reported the results of a study on the application of immunonutrion in peri-operative (pre and postoperative) in head and neck cancer for all patients malnourished or not. In preoperative we used an oral treatmentand in postoperative an enteral one.

MATERIALS AND METHODS

Prospective study concerning 78 patients (47 malnourished versus 31 not) having had heavy head and neck curative cancerology surgery. The mean follow up was of 10 months (from 7 to 16 month). They peri-operative immuno-enriched diet consisted, in pre-operative of 1000 kcal/j during 7 days of oral immunonutrition (Impact), and in post-operative, 1500 kcal/j during 10 days of enteral immunonutition (Crucial). The nutritional state was evaluated in pre-operative by simple clinical and biological parameters (size, weight, CMI "Corporal Mass Index", albumin, NRI "Nutritional Risk Index"), and in post-operative by the evolution of the weight and the CMI. The palatability of the product used in pre-operative and the patients' compliance to the treatment are studied using the satisfaction's multiple choice question paper.

RESULTS

The study showed an improvement of the patients' nutritional and general state (regain appetite, less marked asthenia) and of the quality of life. The product used in preoperative was well tolerated, this oral supplementation led to the same beneficial effects of the enteral's. At eight days in preoperative, the average weight was 62.35 kg, the average CMI was 20.93, and the average NRI was 94.12. In post-operative the patients' nutritional state improved: at eight days, the average loss of weight was 2.82 kg, the average CMI was 22.2. At one and six months after respectively the average gain of weight was 2.17 kg and 6.11 kg, the average CMI was 23.71 and 25.16. The application of this protocol decreased the post-operative complications (13% reduction of the infectious complications and 6% diminution of the fistulas). The time of hospitalization is then reduced (1.7 days), and the life's longevity is improved.

CONCLUSION

The results produced by this study, demonstrate the necessity to apply a peri-operative immuno-enriched diet systematically for all the patients with and without a degraded nutritional state, undergoing a heavy head and neck curative cancerology surgery.

Epidemiology of severe Streptococcus pyogenes disease in Europe

The past 2 decades have brought worrying increases in severe Streptococcus pyogenes diseases globally. To investigate and compare the epidemiological patterns of these diseases within Europe, data were collected through a European Union FP-5-funded program (Strep-EURO). Prospective population-based surveillance of severe S. pyogenes infection diagnosed during 2003 and 2004 was undertaken in 11 countries across Europe (Cyprus, the Czech Republic, Denmark, Finland, France, Germany, Greece, Italy, Romania, Sweden, and the United Kingdom) using a standardized case definition. A total of 5,522 cases were identified across the 11 countries during this period. Rates of reported infection varied, reaching 3/100,000 population in the northern European countries. Seasonal patterns of infection showed remarkable congruence between countries. The risk of infection was highest among the elderly, and rates were higher in males than in females in most countries. Skin lesions/wounds were the most common predisposing factor, reported in 25% of cases; 21% had no predisposing factors reported. Skin and soft tissue were the most common foci of infection, with 32% of patients having cellulitis and 8% necrotizing fasciitis. The overall 7-day case fatality rate was 19%; it was 44% among patients who developed streptococcal toxic shock syndrome. The findings from Strep-EURO confirm a high incidence of severe S. pyogenes disease in Europe. Furthermore, these results have identified targets for public health intervention, as well as raising awareness of severe S. pyogenes disease across Europe.

Streptococcus sinensis: an emerging agent of infective endocarditis

The identification by conventional methods of viridans streptococcal species, which are rarely encountered clinically, requires confirmation by genomic methods. We characterized a strain of Streptococcus sinensis responsible for infective endocarditis by sequencing both the 16S rRNA and the manganese-dependent superoxide dismutase genes.

Characteristics and regional variations of group D streptococcal endocarditis in France

The proportion of infective endocarditis (IE) caused by group D streptococci (GDS; formerly Streptococcus bovis) increased markedly in France, to account for 25% of all cases of IE by 1999. In an attempt to explain this phenomenon, a comparative analysis of GDS and oral streptococci (OS) causing IE was performed. This study was based on data collected from a large cross-sectional population-based survey that was conducted in 1999. In total, 559 cases of definite IE were recorded, of which 142 involved GDS and 79 involved OS. Patients with GDS IE were older (62.7 vs. 56.6 years, p 0.01) and had a history of valve disease less frequently than did patients with OS IE (33.8% vs. 67.1%, p <0.0001). At-risk procedures for IE were performed less frequently in patients with GDS than in patients with OS (14.8% vs. 24.1%, p 0.08), but co-morbidities were more frequent in the GDS group (59.9% vs. 32.9%, p 0.0001). Diabetes, colon diseases and cirrhosis were also more frequent in the GDS group (p 0.006, p <0.0001 and p 0.08, respectively). Rural residents accounted for 31.0% of the GDS group, but for only 15.2% of the OS group (p 0.001). Likewise, the proportion of GDS IE was higher in regions with mixed (urban and rural) populations (Franche-Comté 81.8%, Marne 68.7%, Lorraine 70.3% and Rhône-Alpes 65.3%) than in exclusively urban regions (Paris and Ile de France 58.0%). Further investigations are required to elucidate the link in France between the incidence of GDS IE, rural residency and nutritional factors.

Prospective Evaluation of a Polymerase Chain Reaction–ELISA Targeted toAspergillus fumigatusandAspergillus flavusfor the Early Diagnosis of Invasive Aspergillosis in Patients with Hematological Malignancies

BACKGROUND

Current laboratory and radiological methods for diagnosis of invasive aspergillosis (IA) lack sensitivity and specificity.

METHODS

We prospectively evaluated the diagnostic value of twice-weekly screening for circulating Aspergillus fumigatus and A. flavus DNA with a polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA).

RESULTS

Among the 201 adult patients with hematological malignancies who were included in the study, 55 IA cases were diagnosed. On the basis of the analysis of 1205 serum samples from 167 patients, the sensitivity, specificity, and positive and negative predictive values of the PCR-ELISA for proven and probable IA cases were 63.6%, 89.7%, 63.6%, and 89.7%, respectively, when samples with 2 consecutive positive results were used. The use of a combination of the PCR-ELISA and a galactomannan (GM) assay increased the sensitivity to 83.3%, increased the negative predictive value to 97.6%, and decreased the specificity to 69.8%. In most patients with IA, PCR-ELISA positivity anticipated or was simultaneous with the initiation of antifungal therapy, the abnormalities found by computed tomography, the mycological/histological diagnosis, and the GM positivity. Overall, 56.3% of the patients had at least 1 positive sample, and the false single-positive rate was 44.8%.

CONCLUSIONS

In addition to serial screening for GM antigenemia and radiological surveillance, PCR-ELISA may improve the rates of early diagnosis of IA and the management of patients with hematological malignancies.

[First reported cases of Streptococcus pyogenes meningitis in Central African Republic]

Streptococcus pyogenes or group A streptococcus is an uncommon cause of bacterial meningitis. The purpose of this report is to describe two cases of Streptococcus pyogenes meningitis observed in Bangui, Central African Republic. The first case occurred in a 44-year-old woman who also presented pyodermitis. The second case involved a 34-year-old woman who also presented chronic middle ear infection and AIDS. Both strains of Streptococcus pyogenes were classified as biotype group 5 and showed resistance to tetracycline. They were also T-nontypable and of the emm 117 genotype and 117.1 subtype. Pulsed-field gel electrophoresis confirmed that both strains originated from the same clone.

Bacteremia caused by an undescribed species of Janibacter

A yellow-pigmented rod- to coccoid-shaped coryneform microorganism was isolated from the blood of a patient with acute myeloid leukemia. It was identified by 16S rRNA gene sequencing as a previously undescribed species of Janibacter. The isolate was susceptible to penicillins, aminoglycosides, fluoroquinolones, and glycopeptides.

Molecular characterization of Streptococcus pyogenes isolates to investigate an outbreak of puerperal sepsis

OBJECTIVE

To describe microbiological characteristics and epidemiologic features of an outbreak of postpartum endometritis.

METHODS

Various markers were investigated in five patients and three throat carriage isolates of Streptococcus pyogenes obtained during an outbreak of endometritis occurring in a 13-week period. Molecular characterization included biotyping, T-serotyping, emm gene sequence and restriction, pulsed-field gel electrophoresis (PFGE), and random amplified polymorphic DNA (RAPD) analysis.

RESULTS

Biotype, T-serotype, and genotypic data (emm analysis, PFGE, and RAPD analysis) revealed a close relationship among the isolates from three patients, suggesting that cross-contamination had occurred. These isolates were biotype 1, T type 28, and emm type 28. The isolates from one patient and one carrier differed from those of the index patient by minor variations of the emm amplicon restriction pattern, PFGE pattern, or RAPD pattern. The remaining isolates were phenotypically and genetically different.

CONCLUSION

Identification of different isolates demonstrated that different strains may circulate simultaneously during a true outbreak and that the predominant strain might persist for several months.

Emergence of macrolide-resistant Streptococcus pyogenes strains in French children

We studied the antimicrobial susceptibility of 322 Streptococcus pyogenes throat isolates from French children and their serotype and genomic diversity. A total of 22.4% were erythromycin resistant, and 69.4, 4.2, and 26.4% of these isolates harbored ermB, ermA, and mefA, respectively. Increasing resistance in France is mainly associated with a few emm type 28 clones.

[Evaluation of Prolex for the rapid identification of streptococci isolated in medical microbiology]

The need to rapidly identify streptococci responsible for acute infectious diseases has led to the development of agglutination techniques that are able to identify streptococcal group antigens (A, B, C, D, F, and G) directly from primoculture colonies on blood agar. The Prolex agglutination tests (Pro-Lab Diagnostics, Richmond Hill, Ontario, Canada), distributed in France by i2a, have been used for the determination of group antigens of 166 isolates of streptococci and enterococci previously identified in the National Reference Center for Streptococci. The results obtained with the Prolex reagents have permitted to correctly identify all pyogenic beta-hemolytic streptococci (23 Streptococcus pyogenes, 21 Streptococcus agalactiae, 33 Streptococcus dysgalactiae subsp. equisimilis including 6 group C and 27 group G, and 5 Streptococcus porcinus including 4 group B). Four differences between unexpected agglutinations (A or F) and species identifications have been obtained. These differences were observed for four non-hemolytic isolates of Streptococcus mutans, Streptococcus gordonii, Streptococcus infantarius, and Streptococcus suis. The anti-D reagent has been of value as a marker for isolates of enterococci. Thus, these results confirm the abilities of these agglutination tests for the grouping of beta-hemolytic streptococci. Moreover, the use of Prolex has the advantage to be rapid because of the non-enzymatic but chemical extraction of streptococcal antigens.

Clonal spread of emm type 28 isolates of Streptococcus pyogenes that are multiresistant to antibiotics

Fifty-three pharyngitis-related and invasive isolates of Streptococcus pyogenes that are resistant to bacitracin were collected. They were also resistant to streptomycin, kanamycin, macrolides, lincosamides, and streptogramin B. These multiresistant isolates were of emm type 28 and clonally related as shown by pulsed-field gel electrophoresis.

Induction of a mucosal immune response to the streptococcal M protein by intramuscular administration of a PADRE-ASREAK peptide

In a previous study, it was shown that an intramuscular administration of amino acid PADRE-ELDKWA sequence induced a mucosal immune response to a conserved epitope of human immunodeficiency virus in mice. In the same model, here it is shown that this method can be used with a selected peptide from the M protein of group A streptococci. The PADRE-ASREAK sequence was injected in mice by the intramuscular route. Antibodies against M protein were detected in extracts of mucosal tissues and in serum. The repertoire isotypes of serum immunoglobulin G (IgG) and mucosal IgA and IgG antibodies varied, according to the dose of injected peptide. The highest mucosal IgA antibody response was obtained with 0.01 micro g of antigen per injection, whereas the systemic IgG antibody response increased with 10 micro g of antigen. Mucosal antibody production against streptococci was confirmed by immunofluorescence analysis. These results provide evidence that this novel approach of mucosal vaccination may be of advantage for bacterial systems and suggest a new field of investigation based on synthetic peptide analogues.

Impact of susceptibility to antibiotics of streptococci & enterococci isolated from patients with infective endocarditis on antibiotic treatment

BACKGROUND & OBJECTIVES

Streptococci and enterococci are the most frequent pathogens causing infective endocarditis. In order to update the recommendations for both curative and prophylaxis treatment, the susceptibility to antibiotics of the most prevalent species of Streptococcaceae isolated from the patients with infective endocarditis was determined.

METHODS

Streptococcal and enterococcal isolates (n=133) isolated from confirmed cases of infective endocarditis during a one-year prospective survey conducted in 1999 in France were studied. The identification of 106 streptococci and 27 enterococci to the species level was carried out by conventional methods. Their susceptibility to ten antibiotics used in curative or prophylactic treatment was measured. Minimal inhibitory concentrations were determined by agar dilution method.

RESULTS

All the streptococcal and enterococcal isolates were susceptible to 4 mg/l or less of penicillin or amoxicillin. High levels of resistance to aminoglycosides were observed in two species, Streptococcus gallolyticus subsp. gallolyticus and Enterococcus faecalis. All isolates were susceptible to glycopeptides. Resistance to erythromycin, clindamycin, and pristinamycin was restricted to some species.

INTERPRETATION & CONCLUSION

Curative treatments recommended for streptococcal or enterococcal endocarditis, including penicillin, amoxicillin or vancomycin in association with gentamicin were found to be appropriate for 98.5 per cent of cases. The emergence of erythromycin resistance in oral streptococci led to the use of pristinamycin in oral prophylactic treatment in patients allergic to beta-lactams.

Epidemiological markers of group A streptococcal infections in France

BACKGROUND & OBJECTIVES

A limited number of biotypes, T-types, and emm-types have been found to be associated with invasive isolates of group A streptococci, confirming the involvement of the M protein in virulence and its importance as an epidemiological marker. In this study, the epidemiological markers in the clinical isolates of group A streptococci were compared in invasive and non invasive isolates.

METHODS

From 1998 to 2001, 141 invasive and 353 non invasive isolates in France were studied and their biotype, T-type, and emm-type were determined.

RESULTS

The invasive isolates were mostly obtained from blood whereas the non invasive isolates were isolated from throat. Most of the isolates were of biotype 1. The invasive isolates were mostly of the T-type 1 associated with emm-type 1. The T-type 4 associated with emm-type 4 and the T-type 28 associated with emm-type 28 were also frequent. Invasive isolates responsible for puerperal sepsis and non invasive isolates were mostly of the T-type 28 associated with emm-type 28.

INTERPRETATION & CONCLUSION

This study confirms the high prevalence of isolates of biotype 1, T-type 1, and emm-type 1 among invasive isolates of group A streptococci. The emm-type 28 associated with T-type 28 was frequently observed in non-invasive isolates. A prospective study is being conducted to update the prevalence of the different emm-types in France, which will be of importance for the development of future vaccines.

New group D streptococcal species

BACKGROUND & OBJECTIVES

The heterogeneity of group D streptococci led to the identification of various biotypes of Streptococcus equinus and Streptococcus bovis and to the description of new species. The objective of the present study was to improve the phenotypic delineation between species and to clarify their respective phylogenetic position.

METHODS

Physiological and genomic analyses were carried out in 84 representative strains of the group D streptococci. Biotypes were determined with the API 20 strep and rapid ID 32 STREP systems of identification. Quantitative DNA-DNA hybridization under stringent conditions and values of the deltaT(m) allowed to delineate species and subspecies. The phylogenic position of the different genomic groups was determined by comparing the sequences of their 16S rDNA.

RESULTS

Four DNA-clusters, including seven species or subspecies, were characterized. Differential associations of biochemical characters allowed their identification. S. equinus and the type strain of S. bovis belonged to a single species. S. gallolyticus, S. bovis biotype II.2, and S. macedonicus formed a single DNA-cluster including three different subspecies. These were designated as S. gallolyticus subsp. gallolyticus, S. gallolyticus subsp. pasteurianus, and S. gallolyticus subsp. macedonicus. The two other DNA-clusters corresponded to the two subspecies of S. infantarius, and to S. alactolyticus.

INTERPRETATION & CONCLUSION

This study presented a new classification associated with an identification scheme of group D streptococci. The changes in this classification demonstrate the interest of a polyphagic approach of the bacterial identification.

Tracheopulmonary myiasis caused by a mature third-instar Cuterebra larva: case report and review

Myiasis is the infestation of vertebrate tissues with fly larvae (Diptera). Most human cases in North America are subcutaneous forms due to Dermatobia hominis imported from Central and South America. Human cases of myiasis acquired in North America are rare and are primarily subdermal or ophthalmologic forms of infestation caused by early stages of Cuterebra larvae. We report an unusual case of tracheopulmonary myiasis, resulting from the in situ development of a mature cuterebrine larva associated with high eosinophilia. Only two other cases of tracheopulmonary cuterebrid myiasis have been reported in humans, and they are reviewed herein. Cuterebra myiasis (cuterebrosis) remains a rare and aberrant cause of tracheopulmonary disease and is a newly described cause of eosinophilia in humans.

Reappraisal of the taxonomy of the Streptococcus bovis/Streptococcus equinus complex and related species: description of Streptococcus gallolyticus subsp. gallolyticus subsp. nov., S. gallolyticus subsp. macedonicus subsp. nov. and S. gallolyticus subsp. pasteurianus subsp. nov

'Streptococcus bovis/Streptococcus equinus' is a large bacterial complex including different species frequently isolated from infections of humans (Streptococcus gallolyticus, Streptococcus infantarius) or animals (S. bovis, S. equinus, Streptococcus alactolyticus). The separation of S. bovis into three different biotypes has been partially correlated with genetic differentiation. In addition, recent advances in bacterial phylogeny have led to the inclusion of Streptococcus macedonicus and Streptococcus waius in this complex. The aim of this study was to improve physiological differentiation between species related to the complex and to clarify their respective phylogenetic positions. In this study, physiological, genetic and phylogenetic analyses of a set of 88 streptococcal strains were performed. The diversity of strains of S. bovis biotype II was analysed, and it was confirmed that they belong to different species, either S. equinus or S. infantarius. It was demonstrated that S. gallolyticus, S. bovis biotype II.2, S. macedonicus and S. waius form a single DNA cluster separated into three different subspecies. They are delineated by different biochemical traits, limited DNA-DNA relatedness and noticeable divergence in 16S rDNA sequences. According to the current definition of species, the names S. gallolyticus subsp. gallolyticus subsp. nov., S. gallolyticus subsp. pasteurianus subsp. nov. and S. gallolyticus subsp. macedonicus subsp. nov. are proposed for these three subspecies.

Bacteremia caused by Acinetobacter ursingii

Acinetobacter ursingii has not been reported in infectious processes apart from its recent description as a new species. A bacteremia caused by A. ursingii in a patient with a pulmonary adenocarcinoma confirms that this microorganism is an opportunistic human pathogen. The isolate was susceptible to imipenem, aminoglycosides, rifampin, and fluoroquinolones.

Identification of major Streptococcal species by rrn-amplified ribosomal DNA restriction analysis

Amplified ribosomal DNA restriction analysis (rrn-ARDRA) is based on PCR amplification and restriction of a fragment of rRNA genes including 16S and 23S genes and the intergenic spacer. rrn-ARDRA was evaluated for the identification of species within the genus Streptococcus: A total of 148 type and reference strains of pyogenic, oral, and group D streptococci were examined in order to construct a database for identification of streptococci. The amplified product was a single band approximately 4500 bp long. This amplicon was digested separately with three (HhaI, MboII, and Sau3A) restriction endonucleases. Respectively, 27, 26, and 28 major patterns were observed after HhaI, MboII, and Sau3A restrictions. Streptococcal strains belonging to different species had different patterns or different combination of patterns. An identification system based upon a combination of the three restriction patterns in a single database was then proposed. rrn-ARDRA was successfully applied to 11 clinical isolates whose identification to the species level was difficult to obtain by phenotypic analysis. Using a database of well-characterized strains, rrn-ARDRA is a powerful method for the identification of streptococcal isolates.

Changing profile of infective endocarditis: results of a 1-year survey in France

CONTEXT

Since the first modern clinical description of infective endocarditis (IE) at the end of the 19th century, the profile of the disease has evolved continuously, as highlighted in epidemiological studies including a French survey performed in 1991.

OBJECTIVE

To update information gained from the 1991 study on the epidemiology of IE in France.

DESIGN AND SETTING

Population-based survey conducted from January through December 1999 in all hospitals in 6 French regions representing 26% of the population (16 million inhabitants).

PATIENTS

Three hundred ninety adult inpatients diagnosed with IE according to Duke criteria.

MAIN OUTCOME MEASURES

Incidence of IE; proportion of patients with underlying heart disease; clinical characteristics; causative microorganisms; surgical and mortality outcomes.

RESULTS

The annual age- and sex-standardized incidence was 31 (95% confidence interval [CI], 28-35) cases per million, not including the region of New Caledonia, which had 161 (95% CI, 117-216) cases per million. There was no previously known heart disease in 47% of the cases. The proportion of prosthetic-valve IE was 16%. Causative microorganisms were: streptococci, 48% (group D streptococci, 25%; oral streptococci, 17%, pyogenic streptococci, 6%); enterococci, 8%; Abiotrophia species, 2%; staphylococci, 29%; and other or multiple pathogens, 8%. Blood cultures were negative in 9% and no microorganism was identified in 5% of the cases. Early valve surgery was performed in 49% of the patients. In-hospital mortality was 16%. Compared with 1991, this study showed a decreased incidence of IE in patients with previously known underlying heart disease (20.6 cases per million vs 15.1 cases per million; P<.001); a smaller incidence of oral streptococcal IE (7.8 cases per million vs 5.1 cases per million; P<.001), compensated by a larger proportion of IE due to group D streptococci (5.3 cases per million vs 6.2 cases per million; P =.67) and staphylococci (4.9 cases per million vs 5.7 cases per million; P =.97); an increased rate of early valve surgery (31.2% vs 49.7%; P<.001); and a decreased in-hospital mortality rate (21.6% vs 16.6%; P =.08).

CONCLUSION

Although the incidence of IE has not changed, important changes in disease characteristics, treatment, and outcomes were noted.