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The North Anatolian Fault Zone (NAFZ) is the major transform system that accommodates the westward movement of the relatively rigid Anatolian block with respect to Eurasia. Mitigating the hazard associated with devastating earthquakes requires understanding how the NAFZ accumulates and releases the potential energy of elastic deformation both in space and in time. In this study, we focus on the central bend of the NAFZ where the strike of the North Anatolian Fault (NAF) changes from N75° to N105° within less than 100 km, and where a secondary fault system veers southwards within the interior of Anatolia. We present interseismic velocity fields obtained from a Persistent-Scatterers (PS) Interferometric radar analysis of ERS and Envisat radar archives. Despite the high vegetation cover, the spatial density of measurements is high (∼10 PS/km2 in average). Interseismic velocities presented below indicate a velocity change of ∼6–8 mm/yr along the satellite line-of-sight (LOS) mainly centred on the NAF surface trace, and are in good agreement with the GPS velocity field published previously. The observed deformation is accommodated within a zone of ∼20 to 30 km width, in this area where no surface creep has been reported, contrary to the Ismetpasa segment located ∼30 km to the west of this study zone. Although less conspicuous, ∼2–3 mm/yr (∼1 mm/yr along the LOS) of the total deformation seems to be localized along the Lacin Fault. The overall agreement with horizontal GPS measurements suggests that the vertical component of the ground deformation is minor. This is confirmed, over the western part of our study zone, by the 3-D estimation of the ground deformation from the combination of the GPS- and the PS-mean velocity fields. However, a specific pattern of the PS velocity fields suggests that an area, enclosed between two faults with roughly south–north orientation, experiences uplift. The PS analyses of radar time-series both prior and posterior to the Izmit and Dûzce earthquakes indicate that these events did not induce detectable velocity changes in this central bend. The only temporal changes we identify are due to a moderate local earthquake (Mw 5.7, 1996 August 14) whose precise location and coseismic deformation are determined here. Finally, we propose a model of slip-rate distribution at depth along the NAF from the joint inversion of the GPS and PS mean velocity fields. This model suggests a long-term slip-rate of ∼20 mm/yr for a rather uniform locking depth in the range of 15–20 km. However, the locking depth increases to ∼25–30 km in the section comprised between longitudes E34°20’ and E34°50’. This lateral evolution is in general agreement with the earthquake distribution at depth from three different catalogues. [ABSTRACT FROM AUTHOR]

Clinical microbiology has always been a slowly evolving and conservative science. The sub-field of bacteriology has been and still is dominated for over a century by culture-based technologies. The integration of serological and molecular methodologies during the seventies and eighties of the previous century took place relatively slowly and in a cumbersome fashion. When nucleic acid amplification technologies became available in the early nineties, the predicted "revolution" was again slow but in the end a real paradigm shift did take place. Several of the culture-based technologies were successfully replaced by tests aimed at nucleic acid detection. More recently a second revolution occurred. Mass spectrometry was introduced and broadly accepted as a new diagnostic gold standard for microbial species identification. Apparently, the diagnostic landscape is changing, albeit slowly, and the combination of newly identified infectious etiologies and the availability of innovative technologies has now opened new avenues for modernizing clinical microbiology. However, the improvement of microbial antibiotic susceptibility testing is still lagging behind. In this review we aim to sketch the most recent developments in laboratory-based clinical bacteriology and to provide an overview of emerging novel diagnostic approaches.

During a 2-year period, 157 consecutive episodes of respiratory virus infections that occurred in 130 patients with upper or lower respiratory tract infection were analyzed for respiratory viruses. A respiratory virus was identified in 75 episodes (48%), and several viruses were found in 13 episodes: there were a total of 56 influenza A virus infections, 14 respiratory syncytial virus infections, 8 adenovirus infections, 8 infections with parainfluenza virus types 1 or 3, and 7 enterovirus infections. On multivariate analysis, the only variable that predicted progression to pneumonia in patients with an upper respiratory tract infection was the presence of respiratory syncytial virus, whereas lymphocytopenia had a nonsignificant trend. Also, among the 38 patients who had pneumonia at any time during the episode, both respiratory syncytial virus and lymphocytopenia were commonly found. For both epidemiological and therapeutic considerations, frequent screening for respiratory viruses should be incorporated into the routine diagnostic study of patients with hematologic malignancies.

A study was designed to assess the impact of the VITEK 2 automated system and the Advanced Expert System (AES) on the clinical laboratory of a typical university-based hospital. A total of 259 consecutive, nonduplicate isolates of Enterobacteriaceae members, Pseudomonas aeruginosa, and Staphylococcus aureus were collected and tested by the VITEK 2 system for identification and antimicrobial susceptibility testing, and the results were analyzed by the AES. The results were also analyzed by a human expert and compared to the AES analyses. Among the 259 isolates included in this study, 245 (94.6%) were definitively identified by VITEK 2, requiring little input from laboratory staff. For 194 (74.9%) isolates, no inconsistencies between the identification of the strain and the antimicrobial susceptibility determined by VITEK 2 were detected by the AES. Thus, no input from laboratory staff was required for these strains. The AES suggested one or more corrections to results obtained with 65 strains to remove inconsistencies. The human expert thought that most of these corrections were appropriate and that some resulted from a failure of the VITEK 2 system to detect certain forms of resistance. Antimicrobial phenotypes assigned to the strains by the AES for beta-lactams, aminoglycosides, quinolones, macrolides, tetracyclines, and glycopeptides were similar to those assigned by the human expert for 95.7 to 100% of strains. These results indicate that the VITEK 2 system and AES can provide accurate information in tests for most of the clinical isolates examined and remove the need for human analysis of results for many. Certain problems were identified in the study that should be remediable with further work on the software supporting the AES.

The Advanced Expert System (AES) was used in conjunction with the VITEK 2 automated antimicrobial susceptibility test system to ascertain the beta-lactam phenotypes of 196 isolates of the family Enterobacteriaceae and the species Pseudomonas aeruginosa. These isolates represented a panel of strains that had been collected from laboratories worldwide and whose beta-lactam phenotypes had been characterized by biochemical and molecular techniques. The antimicrobial susceptibility of each isolate was determined with the VITEK 2 instrument, and the results were analyzed with the AES to ascertain the beta-lactam phenotype. The results were then compared to the beta-lactam resistance mechanism determined by biochemical and molecular techniques. Overall, the AES was able to ascertain a beta-lactam phenotype for 183 of the 196 (93.4%) isolates tested. For 111 of these 183 (60.7%) isolates, the correct beta-lactam phenotype was identified definitively in a single choice by the AES, while for an additional 46 isolates (25.1%), the AES identified the correct beta-lactam phenotype provisionally within two or more choices. For the remaining 26 isolates (14.2%), the beta-lactam phenotype identified by the AES was incorrect. However, for a number of these isolates, the error was due to remediable problems. These results suggest that the AES is capable of accurate identification of the beta-lactam phenotypes of gram-negative isolates and that certain modifications can improve its performance even further.

Background: Caring for cancer patients is expensive, warranting verification that health care organization works in a satisfactory way. A first step of this evaluation deals with the description of the pathway followed in the health care system by the patient., Methods: 671 breast cancer cases were diagnosed in Isère in 1995. According to the place where each treatment (surgery, chemotherapy, radiotherapy) was performed, we described pathways for the patient, either entirely private, public or mixed. Characteristics of the patient (age, place of residence), of the disease (extent of disease, way of discovery) and of the physician (general practitioner, specialist) might have influenced the choice of this pathway. We described and tested the distribution of these characteristics within the 3 groups using univariate analysis. Relative risk of being affected to the private pathway compared to the public one was computed, after adjusting for age, type of physician, extent of disease, way of discovery and sanitary area, using a multivariate analysis (logistic regression)., Results: In the department of Isère, the private pathway cared for 55% of breast cancers, the public one 23% and the mixed one 19%. There was no preferential recruitment according to age, physician type, presence of metastasis or of the rural or urban residence. In sanitary area number 5, characterized by an important attraction of the patients by the nearby department of Rhône, 41% of the patients were cared for the private pathway, compared to 63% in sanitary area 4, where most patients were treated in the main town of Isère: Grenoble. After early breast cancer detection with mammography instead of breast cancer screening, probability of being cared for in the private pathway was 2-fold higher (OR = 2) than in the public one., Conclusion: In Isère department, early breast cancer detection with mammography is in favor of the private pathway. This is not true for physician type, neither for characteristics of the patient or extent of the disease. Finally, the distance to next department of oncology or radiotherapy plays a major role.

Prevalence of malignant neoplasm is a basic health indicator used in order to evaluate needs in medical equipment for treatment and follow-up of cancer patients. Data on prevalence are regularly published by Northern European countries. Thames and Connecticut cancer registries. In France available information on prevalence are scanty, because follow-up of cancer patients is not easy. Therefore, we used a statistical method to evaluate prevalence from incidence and mortality in the Rhône-Alpes area (France, 5,300,000 inhabitants) in 1990, using the department of Isère population based registry. For females, figures for breast carcinoma and colorectal carcinoma are respectively 25,000 and 5,700, and, for males, 5,700 colorectal carcinoma. For 5 year partial prevalence, these figures are respectively 11,300, 3,100 and 3,500. The ratio prevalence/incidence is 8.9 for breast in females, 5.8 for colorectal carcinoma in females and 4.8 for colorectal carcinoma in males with a steep decrease for 5 year partial prevalence (4 for breast carcinoma, 3.1 for females colorectal carcinoma and 2.9 for males colorectal carcinoma). These ratios are consistent with those observed elsewhere in Europe.

The need for public health planning in France, recently led to the development of a Regional Program in Public Health Organisation (SROS) to describe geographical distribution of facilities and health care activities, in accordance with population needs. Isere Cancer Registry, using its own mortality and morbidity data, evaluated incidence (16,000 new cases each year) and prevalence (100,000 cases) in the Rh-one-Alpes area. Thus, knowing incidence and prevalence of cancer within each district by age and sex, it became much easier for public and private hospitals to quantify their future activities. Today, French cancer registries are conducting methodological studies to improve prevalence estimates, in order to use them in predicting future costs of health care in oncology.

The determination of minimal inhibitory concentrations (MICs) is cumbersome, but remains necessary in certain cases. We tested the two ATB MIC experimental strips (Biomérieux SA), of which each contains 4 antimicrobials of the same class. These strips can be read automatically. The MIC quinolone strip contains nalidixic acid, pefloxacin, ofloxacin and ciprofloxacin, whereas the MIC macrolide (lincosamide-streptogramin) strip contains erythromycin, clindamycin, lincomycin, and pristinamycin. In order to evaluate these strips, 102 S. aureus and 63 coagulase negative staphylococci were used. Correlation coefficients for these MICs (micrograms/ml) and disk diffusion inhibition zone diameters (mm) were nalidixic acid -0.59, pefloxacin -0.95, ofloxacin -0.95, ciprofloxacin -0.91, erythromycin -0.98, clindamycin -0.96, lincomycin -0.96, and pristinamycin -0.64. Using the Biomic system (Giles Scientific USA), the same zone diameters were converted to MICs (micrograms/ml). Rates of agreement (+/- 1 dilution) between ATB MICs and Biomic MICs were nalidixic acid 96 p. cent, ciprofloxacin 98 p. cent, erythromycin 99 p. cent and clindamycin 98 p. cent. Rates of agreement between MICs for the same strains determined using agar dilution and ATB MICs were nalidixic acid 93 p. cent, pefloxacin 100 p. cent, ciprofloxacin 99 p. cent, ofloxacin 94 p. cent and erythromycin 96 p. cent. The ATB MIC strips are an easy-to-use tool for MIC determination and their composition is well-suited to the study of phenotypic resistance and detection of low-level resistance.

ATB Plus Expert (Biomérieux SA) is an expert system which has been developed to perform an interpretative reading of ATB susceptibility tests. The system was tested on the results obtained for 217 strains of enterobacteriaceae. These strains were selected in order to cover a maximum of bacterial species and resistance mechanisms. The isolates were tested on rapid ATB E, rapid ATB G-, rapid ATB Ur, ATB G- and ATB Ur strips. In parallel, a disc diffusion susceptibility test was performed with 5 discs of aminoglycosides (kanamycin, gentamicin, tobramycin, netilmicin, amikacin) and the interpretation was carried out according to the criteria usually followed. Of the 217 strains tested, 122 showed a resistance phenotype. Only the rapid ATB E strips included kanamycin and allowed the detection of APH(3') phenotypes. Amikacin was not included in the ATB Ur strip, consequently it was impossible to discriminate AAC(3)-II and AAC(6') + AAC(3)-I phenotypes. 12 strains did not grow within 5 hours using the rapid ATB methodology. Not taking into account the problems previously encountered, different phenotypes between the 6 susceptibility tests were found for 16 strains. In 5 cases the expert system detected an anomaly instead of the correct phenotype, and in 3 cases of unknown phenotypes, the answers were variable. In the other cases, the main difficulty was the detection of the isolated resistance to gentamicin (AAC(3)-I phenotype). The expert system automatically corrects the susceptibility test result according to the phenotype observed.

The individual results of the antibiotic susceptibility tests of 110 Enterobacteriaceae to 31 antibiotics (beta-lactamines, aminoglycosides, quinolones) have been compared on Mueller-Hinton and Isosensitest. No difference between the diameters of inhibition has been shown by the paired t test or signed rank test. The identification of the phenotypes of resistance (resistance patterns) were compared by principal component analysis and by help of an expert system. The patterns are identical in 99 cases and different in 11 cases. Six pattern were erroneous on Mueller-Hinton and 5 on Isosensitest. Globally both media gave a similar comparable answer in these conditions.

The time-killing curves of three strains of Pseudomonas aeruginosa (PA01, ATCC10145 and ATCC27853) exposed to five concentrations of polymyxin B comprised: a latency phases, one or two decreasing phases and for the low polymyxin B concentrations a growth phasis. The five antibiotic concentrations were chosen to have a weak bactericidal effect such that decreasing exponential or biexponential models can be fitted to the data. In our experimental conditions, increasing Ca++ and Mg++ concentrations in the medium (Mueller-Hinton) reduced the bactericidal effect and increased the growth phases. Increasing inoculum (10(5) to 10(7) CFU/ml) decreased the bactericidal effect observed with polymyxin B.

The time killing curves of five strains of Escherichia coli (ATCC 25922, ATCC 29194, CIP 54125, CIP 54127, CIP 54117 (K 12)) exposed to five concentrations of polymyxin B are similar: latency phasis, two decreasing phasis and for the low polymyxin B concentrations growth phasis. In our experimental conditions, the Mg(+)+ and Ca(+)+ concentrations of the medium (Mueller-Hinton; medium A: Ca(+)+ = 9 mg/l, Mg(+)+ = 0.5 mg/l; medium B: Ca(+)+ = 35 mg/l, Mg(+)+ = 15.5 mg/l; medium C: Ca(+)+ = 60 mg/l, Mg(+)+ = 20 mg/l) have no time effect upon the killing curves. A decreasing biexponential model can be fitted to the data. Such a model is compatible with interaction between antibiotic and bacterium and can be formalized accorrding to the equation: T + ATB K1 in equilibrium of K2 T* - ATB K3----ATB + dead with ATB: Polymyxine B in excess, T: target bacterium and T*: modification target bacterium.

This work has been performed to study the inoculum effect on the in vitro activity of LY 146032, a new lipopeptide antibiotic. A statistical analysis (X2 and t test) of the data concerning the MIC of different bacterial groups has been carried out to appreciate the phenomenon. The activity of vancomycin has been compared. A major inoculum effect has been detected for LY 146032. It must be taken into account to evaluate the activity of this new antibiotic.

An expert system (cadi-yac), written in Turbo-Prolog and working on IBM PC and Bacanal + (a management software of microbiology laboratory) was used to recognize and correct the phenotype of antibiotic sensibility. The results were there of API ATB system. The knowledge was adapted from two references works. A routine use of the expert system give a correct recognition of enzymatic profile in more than 80% cases for the beta-lactams and more than 98% cases for the aminosides. The mistakes detected by cadi-yac, were often interpreted as deficiency of API system by humans experts. The expert system mistakes (1.5%) were due composites phenotypes.

The authors report six cases of cicatricial pemphigoid emphasizing the initial sintoms and signs of the disease and its ocular localization in order to make an early diagnosis and an efficient therapeutic control; so as to avoid the cicatricial complications. From the therapeutical point of view me propose the use of local therapy and permanent contact lenses.