Examining transmission of gut bacteria to preserved carcass via anal secretions in Nicrophorus defodiens

Direct transmission of bacteria to subsequent generations highlights the beneficial nature of host-bacteria relationships. In insects, this process is often mediated by the production of microbe-containing secretions. The objective of this study was to determine if the burying beetle, Nicrophorus defodiens, utilizes anal secretions to transmit adult digestive tract bacteria onto a small vertebrate carcass; thus creating the potential to aid in carcass preservation or pass digestive tract bacteria to their larval offspring. Using high-throughput Illumina sequencing of the 16S rRNA gene, we characterized bacterial communities of adult beetle digestive tracts, their anal secretions, and prepared mouse carcasses. We also examined unprepared carcass bacterial communities as a means to interpret community shifts that take place during carcass preservation. We found a vast reduction in diversity on prepared carcasses after anal secretion application. Overall, there was little similarity in bacterial communities among adult digestive tracts, anal secretions, and prepared carcasses, suggesting bacterial communities found in adult digestive tracts do not successfully colonize and achieve dominance on prepared carcasses by way of beetle anal secretions. We concluded that N. defodiens does not transmit their digestive tract bacterial communities to prepared carcasses in a wholesale manner, but may transmit key microbes, including core microbiome members, to preserved carcasses that may ultimately act to sustain larvae and serve as inocula for larval digestive tracts.

Fine infrastructure of released and solidified Drosophila larval salivary secretory glue using SEM

The Golgi-derived large secretory granules of Drosophila salivary glands (SGs) constitute the components of the salivary glue secretion (Sgs). The Sgs represents a highly special and unique extracellular composite glue matrix that has not yet been identified outside of Cyclorrhaphous Dipterans. For over half a century, the only major and unambiguously documented function of the larval salivary glands was to produce a large amount of mucinous glue-containing secretory granules that, when released during pupariation, serves to affix the freshly formed puparia to a substrate. Besides initial biochemical characterization of the Sgs proteins and cloning of their corresponding Sgs genes, very little is known about other properties and functions of the Sgs glue. We report here observations on the fine SEM-ultrastructure of the Sgs glue released into to the lumen of SGs, and after it has been expectorated and solidified into the external environment. Surprisingly, in contrast to long held expectations, it appears to be a highly structured bioadhesive mass with an internal spongious to trabecular infrastructure, reflecting the state of its hydratation. We also found that in addition to its cementing properties, it is highly efficient at glueing and trapping microorganisms, and thus may serve a potentially very important immune and defense role. High hydration capacity, the speed by which this glue can dry, uniqueness of its protein composition and spongious infrastructure can provide inspiration for development of potential biomimetics that can attach completely different or incompatible surfaces with high efficiency and strength.

Detection and characterization of Mycoplasma pneumoniae during an outbreak of respiratory illness at a university

An outbreak at a university in Georgia was identified after 83 cases of probable pneumonia were reported among students. Respiratory specimens were obtained from 21 students for the outbreak investigation. The TaqMan array card (TAC), a quantitative PCR (qPCR)-based multipathogen detection technology, was used to initially identify Mycoplasma pneumoniae as the causative agent in this outbreak. TAC demonstrated 100% diagnostic specificity and sensitivity compared to those of the multiplex qPCR assay for this agent. All M. pneumoniae specimens (n=12) and isolates (n=10) were found through genetic analysis to be susceptible to macrolide antibiotics. The strain diversity of M. pneumoniae associated with this outbreak setting was identified using a variety of molecular typing procedures, resulting in two P1 genotypes (types 1 [60%] and 2 [40%]) and seven different multilocus variable-number tandem-repeat analysis (MLVA) profiles. Continued molecular typing of this organism, particularly during outbreaks, may enhance the current understanding of the epidemiology of M. pneumoniae and may ultimately lead to a more effective public health response.

Role of real-time PCR (RT-PCR) in rapid diagnosis of tuberculous mycobacteria in different clinical samples

The study was aimed for molecular detection of mycobacterial DNA in different clinical samples using real-time polymerase chain reaction (RT-PCR) system and rapid diagnosis of tuberculosis. A total of 508 clinical specimens (blood 343, menstrual fluid 53, endometrial tissue 43, body fluid 36, pus from lymph nodes 18, sputum 8, urine 5 and semen 2) were included in this study. We extracted DNA using QIAamp DNA Mini Kit (QIAGEN, Germany) and performed real-time assay using Rotor-Gene Q machine from Corbett Research, Australia for specific amplification of IS6110 sequence of mycobacterial genome. The RT-PCR result was also compared with bacterial culture and acid-fast bacillus staining. RT-PCR assay showed positivity in 52 cases and negative in 456 cases. Corresponding positive results in culture and acid-fast bacillus staining methods were 49 cases and 24 cases respectively. The sensitivity and specificity of detecting Mycobacterium tuberculosis by RT-PCR were 93.87% and 98.69% respectively taking positive culture results as reference standards. The overall positive and negative predictive values were 88.46% and 99.34% respectively. RT-PCR is a useful diagnostic tool for rapid and sensitive detection of mycobacteria in different clinical samples. The easy processing, fast reporting and relative lack of contamination issues make it worthy as a possible replacement to time consuming culture techniques. Moreover, it has added advantage of quantification of mycobacterial DNA, hence bacterial load.

[Application of FilmArray assay for detection of respiratory tract infections in immunocompromised persons]

INTRODUCTION

A variety of viruses and bacteria are responsible for acute upper and lower respiratory tract infections worldwide. Severe and even fatal disease can occur especially in group ofimmunocompromised individuals. Accurate pathogen identification allows clinicians to determine the need for ancillary diagnostic testing, antibacterial and/or antiviral therapy and can motivate decisions regarding hospitalization and infection control measures.

METHODS

We compared the diagnostic performance of FilmArray Respiratory Panel highly multiplexed nucleic acid amplification test with previous used direct immunofluorescence assay. Both assays were performed on a panel of 6 nasopharyngeal-secretion specimens and 6 BALF samples, collected from 12 patients, subjected to allogeneic haematological stem cells transplantation, with lower respiratory tract symptoms.

RESULTS AND CONCLUSIONS

Among viruses detectable by both assays were especially influenzaA virus, parainfluenza viruses type 3 and respiratory syncytial virus. In conclusion, the FilmArray assay is rapid and extremely user-friendly system, with results available in just over one hour with almost no labor involved. In few laboratories its low throughput and qualitative results may be a disadvantage in some clinical settings.

Microorganisms from aphid honeydew attract and enhance the efficacy of natural enemies

Aphids are one of the most serious pests of crops worldwide, causing major yield and economic losses. To control aphids, natural enemies could be an option but their efficacy is sometimes limited by their dispersal in natural environment. Here we report the first isolation of a bacterium from the pea aphid Acyrthosiphon pisum honeydew, Staphylococcus sciuri, which acts as a kairomone enhancing the efficiency of aphid natural enemies. Our findings represent the first case of a host-associated bacterium driving prey location and ovipositional preference for the natural enemy. We show that this bacterium has a key role in tritrophic interactions because it is the direct source of volatiles used to locate prey. Some specific semiochemicals produced by S. sciuri were also identified as significant attractants and ovipositional stimulants. The use of this host-associated bacterium could certainly provide a novel approach to control aphids in field and greenhouse systems.

[Contemporary clinical diagnostics of respiratory tract infections]

The patient population at risk pulmonary infections has increased during the last decade. The spectrum of organisms causing infections has also grown, most of them are viruses Baseline diagnostic assessment include history, clinical examination, radiography and measurements of procalcitonin (PCT), highly sensitive C-reactive protein (hsCRP) and leukocyte count. PCT represents a good biological marker for difficult diagnoses in critically ill patients and is superior to CRP. Chest x-rays seldom give enough information to determine the exact cause of the abnormality, but they can help a doctor to determine whether and which other tests are needed to make a diagnosis. Microbiologic advances have helped to facilitate the laboratory diagnosis of some pathogens. Cultures of respiratory specimens are some times useful but the gold standard for diagnosis of pulmonary infection is blood culture. Immunoassays are available for the detection of antigen in nasopharyngeal secretions (respiratory syncytial virus, influenza), and in urine (Legionella spp.). Rapid-culture techniques are available for the culture and detection of various viruses. Recently PCR-based techniques and RT-PCR assist in the detection of Legionella, Chlamydia, Mycoplasma, Pneumocystis carinii and mycobacteria species. This article presents a practical approach to the differential diagnosis of pulmonary infections.

Antimicrobial peptides in nasal secretion and mucosa with respect to S. aureus colonisation in Wegener´s granulomatosis

OBJECTIVES

Nasal S. aureus carrier rates are significantly higher in patients with Wegener's granulomatosis (WG) compared to healthy controls (HC), and nasal colonisation is a risk-factor for relapse. Antimicrobial peptides (AMP) are important defence molecules maintaining an intact barrier function. It is the aim of this study to see if there is a possible link between the nasal AMP pattern and S. aureus colonisation, a link which has not been investigated so far.

METHODS

ELISA was applied to quantify LL-37 and hBD-3 concentrations in nasal secretions (14 WG patients, 13 HC) with and without nasal S. aureus colonisation. Immunohistochemistry was used to detect the cellular sources of AMP in the nasal mucosa. Functional analyses of primary nasal epithelial cell cultures (NEC) of these groups stimulated with S. aureus were performed.

RESULTS

LL-37 was found in significantly higher concentrations in colonised individuals (WG: p=0.001; HC: p=0.014).Using immunohistochemistry, local cellular sources for AMP could be demonstrated. After stimulation with S. aureus, significantly higher concentrations of LL-37 and hBD-3 could be detected in the supernatant of NEC of WG patients (LL-37: p=0.001; hBD-3: p=0.001) and HC (LL-37: p=0.019; hBD-3: p=0.001). HBD-3 concentrations were significantly lower in the supernatant of stimulated NEC of WG patients compared to the NEC of HC (p=0.032), and the dynamic range of the hBD-3 answer was significantly smaller in WG compared to HC (p=0.016).

CONCLUSIONS

The dynamic response towards challenges with microbes is dysregulated in WG, and this might be one reason for higher S. aureus colonisation rates in WG.

[Characteristics of microbiological diagnosis of chronic bacterial prostatitis]

We made a microbiological study of the urine and prostatic secretion (Meares-Stamey test) of 35 patients with chronic bacterial prostatitis (CBP) aged 35-75 years. We conducted a bacterial assay, determined species, sensitivity to synthetic antibacterial fluoroquinolone drugs. A total of 163 bacterial strains were isolated, of them 13 were staphylococcal. Gram-negative bacteria were identified in the test biomaterial only in 16.6% cases. The analysis of staphylococcal sensitivity showed the highest antistaphylococcal effectiveness of levofloxacin and lomefloxacin. Our study confirms an essential role of staphylococcal bacteria in CBP etiology.

Geosmithia argillacea: an emerging pathogen in patients with cystic fibrosis

We report eight cases of airway colonization by Geosmithia argillacea in patients with cystic fibrosis. This filamentous fungus, resembling members of the genera Penicillium and Paecilomyces, was identified by molecular analysis. All patients carried a mutation on each CFTR (cystic fibrosis transmembrane conductance regulator) allele, with at least one copy of the F508del mutation. The first isolation of this fungus occurred from F508del-homozygous patients at a younger age than in F508del-heterozygous patients. Before recovery of G. argillacea, all patients were treated with itraconazole; two of them had also received voriconazole for an Aspergillus fumigatus infection. However, antifungal susceptibility patterns showed high MICs of voriconazole for all isolates, and high MICs of amphotericin B and itraconazole for the majority of them, but mostly low minimum effective concentrations (MECs) of caspofungin. The appearance and persistence of G. argillacea in the airways were not associated with exacerbation of the disease. However, the clinical implications of G. argillacea, particularly in immunocompromised patients, remain a concern, particularly given recent observations suggesting that this fungus may also cause disseminated infections.

Antifungal susceptibility of yeasts isolated from secrection of inflamed mammary glands in cows

Antifungal susceptibility of 150 strains of yeasts isolated from the infected mammary secretion of cows was determined. Their susceptibility to amphoterycin B, nystatin, flucytosine, tioconazole, ketoconazole, miconazole, fluconazole and clotrimazole was evaluated using the disc diffusion method on Yeast Nitrogen Base (YNB) and filter paper discs. The most active antifungal agents in vitro were found to be: tioconazole--96.7%, nystatin--95.4%, amphoterycin--94.0%, and flucytosine--92.7% of susceptible strains; the least active were fluconazole and clotrimazole--39.3% and 60.0% of susceptible strains, respectively. The individual species of yeasts were characterized by varied susceptibility to individual therapeutics.

Streptococcus pneumoniae coinfection is correlated with the severity of H1N1 pandemic influenza

Background

Initial reports in May 2009 of the novel influenza strain H1N1pdm estimated a case fatality rate (CFR) of 0.6%, similar to that of seasonal influenza. In July 2009, however, Argentina reported 3056 cases with 137 deaths, representing a CFR of 4.5%. Potential explanations for increased CFR included virus reassortment or genetic drift, or infection of a more vulnerable population. Virus genomic sequencing of 26 Argentinian samples representing both severe and mild disease indicated no evidence of reassortment, mutations associated with resistance to antiviral drugs, or genetic drift that might contribute to virulence. Furthermore, no evidence was found for increased frequency of risk factors for H1N1pdm disease.

Methods/Principal Findings

We examined nasopharyngeal swab samples (NPS) from 199 cases of H1N1pdm infection from Argentina with MassTag PCR, testing for 33 additional microbial agents. The study population consisted of 199 H1N1pdm-infected subjects sampled between 23 June and 4 July 2009. Thirty-nine had severe disease defined as death (n = 20) or hospitalization (n = 19); 160 had mild disease. At least one additional agent of potential pathogenic importance was identified in 152 samples (76%), including Streptococcus pneumoniae (n = 62); Haemophilus influenzae (n = 104); human respiratory syncytial virus A (n = 11) and B (n = 1); human rhinovirus A (n = 1) and B (n = 4); human coronaviruses 229E (n = 1) and OC43 (n = 2); Klebsiella pneumoniae (n = 2); Acinetobacter baumannii (n = 2); Serratia marcescens (n = 1); and Staphylococcus aureus (n = 35) and methicillin-resistant S. aureus (MRSA, n = 6). The presence of S. pneumoniae was strongly correlated with severe disease. S. pneumoniae was present in 56.4% of severe cases versus 25% of mild cases; more than one-third of H1N1pdm NPS with S. pneumoniae were from subjects with severe disease (22 of 62 S. pneumoniae-positive NPS, p = 0.0004). In subjects 6 to 55 years of age, the adjusted odds ratio (OR) of severe disease in the presence of S. pneumoniae was 125.5 (95% confidence interval [CI], 16.95, 928.72; p<0.0001).

Conclusions/Significance

The association of S. pneumoniae with morbidity and mortality is established in the current and previous influenza pandemics. However, this study is the first to demonstrate the prognostic significance of non-invasive antemortem diagnosis of S. pneumoniae infection and may provide insights into clinical management.

A Chryseobacterium meningosepticum colonization outbreak in a neonatal intensive care unit

PURPOSE

To report the epidemiologic, bacteriologic, and clinical features of a Chryseobacterium meningosepticum outbreak in a neonatal intensive care unit (NICU) of a referral teaching hospital.

PATIENTS AND METHODS

From April to October 2002, a strain of C. meningosepticum was isolated from four neonates in the NICU. All neonates were colonized in the endotracheal tubes and respiratory secretions, but none of them progressed to clinical infection. Multiple samples were obtained for cultures.

RESULTS

Pulsed-field gel electrophoresis (PFGE) of isolates showed them to be representatives of a single strain. Environmental surveillance did not reveal the C. meningosepticum source. None of the neonates received specific treatment. The outbreak was only controlled by reinforcement of the usual measures and no additional colonization/infection was confirmed for more than a year after the last case.

CONCLUSION

This study suggests that C. meningosepticum colonization in neonates does not necessarily lead to infection and that such colonization outbreaks may be controlled with emphasis on the standard precautions.

[Investigation of the situation of vaginal microflora in healthy women population]

OBJECTIVE

To assess the distribution of vaginal microflora in healthy women and investigate their cognition of lower reproductive tract infection-related knowledge as well as personal hygiene habits and character of behavior in seeking medical treatment.

METHODS

Total of 1660 healthy women who had physical check-ups at the Medical Center of Renji Hospital were selected and received gynecologic examination, as well as routine examination, pH examination and bacterial culture of the vaginal discharge. In addition, 860 of them were randomly selected for questionnaire survey, in which reproductive tract infection -related knowledge and personal hygiene habits as well as behavior in seeking medical treatment were involved.

RESULTS

Among the 1660 censused women, vaginal average pH was 4. 16 +/- 0.21. The positive rate of Candida in vaginal discharge routine examination was 3.86% (64/1660), which was lower than that in aerobes culture 7.71% (128/1660). Candida albicans was the most populous species 78.9% (101/128), followed by 7.8% (10/128) and 7.0% (9/128) for the Candida glabrata and Candida krusei respectively. The most populous species of vaginal microflora were hemolytic streptococcus A (63.80%, 1059/1660), Staphylococcus epidermidis (14.28%, 237/1660), and Enterococcus faecalis (D) group (11.44%, 190/1660). The questionnaire survey showed that 88.4% (760/860) of 860 women took active treatment when feeling unwell, 92.1% (792/860) of them had good hygiene practices, and only 21.2% (182/860) had the habit of vaginal douching. In addition, 50.0% (430/860) of them had the desire to obtain reproductive health knowledge through out-patient consultation.

CONCLUSIONS

Vulvovaginal Candida disease ranks the first in all types of vaginitis, among which, Candida albicans is the most populous species followed by the Candida glabrata and Candida krusei. Hemolytic streptococcus A and Staphylococcus epidermidis are the most common species of vaginal microflora in healthy women. The censused women have high awareness of reproductive health care and pay much attention to common gynecologic diseases such as lower reproductive tract infection. Nevertheless, we should strengthen the public education of reproductive health-related knowledge.

[Respiratory tract fluid microbiology in an intensive care unit]

OBJECTIVE

to know patterns of antimicrobial resistance of bacterial isolates from tracheal aspirates in an Intensive Care Unit and to evaluate the cases of ventilator-associated pneumonia.

METHODS

antibiotic sensitivity test was done. A comparison was made between patients with nosocomial pneumonia reported by infection surveillance team against those reported by the attending physician with the infectious disease consultant.

RESULTS

Pseudomonas aeruginosa was the bacteria most frequently reported with 134 isolates (26 %), 71 were multiple-drug-resistant; followed by Staphylococcus with 122 isolates (24 %), of which 88 were S. aureus with 62 of them (70 %) methicillin-resistant. Enterobacteriaceae, E. coli, K. pneumoniae, E. cloacae, S. marcescens, as well as Acinetobacter sp. and S. maltophilia were occasionally isolated. Candida represented 17 % of the isolates. Three peaks of isolates of S. aureus and P. aeruginosa were identified during the two years of surveillance. There were differences in cases of ventilator associated pneumonia reported by the hospital based epidemiology team and the attending clinicians in collaboration with an Infectious disease consultant.

CONCLUSIONS

prevalence of multiple-drug-resistant Pseudomonas aeruginosa (53 %) and methicillin resistant Staphylococcus (70 %) isolated from the airway is high in our Intensive Care Unit. Enterobacterias, Acinetobacter sp. and Stenotrophomonas maltophilia colonization are low in our Intensive Care Unit.

[Bacteriological study on adult chronic sinusitis operated after endoscopic sinus surgery]

OBJECTIVE

To explore the bacteria isolated from middle nasal meatus, maxillary sinus, ethmoid sinus and postoperative cavity of patients with chronic rhinosinusitis and their characteristics of antibiotic resistance.

METHODS

Eighty-seven patients with chronic rhinosinusitis were operated on by ESS to obtain the pus specimen for bacterial culture and antibiotic susceptibility test, before and 1 month, 3 months and 6 months after operation.

RESULTS

Totally 645 strains (26 species) of bacteria were detected in 464 specimens [total positive rate was 78.9% (366/464)], in which aerobic bacteria was 95.3% (615/645). Gram negative bacteria and gram positive bacteria were 51.2% (330/645) and 48.8% (315/645), respectively. There was supernumerary tendency in detectable rate of gram negative bacteria isolated from postoperative groups. The main pathogens of postoperative patients were gram negative bacteria, with Enterobacter aerogenes, Pseudomonas aeruginosa and Hemophilus influenza occupying the first 3 places. The detectable rate of multiple drug resistance bacteria in postoperative group was much higher than preoperative groups, in which gram negative bacteria was the most, especially for Pseudomonas aeruginosa. There was significant difference in beta-lactamase detectable rate of the bacteria isolated from the delayed recovery group and the preoperative group (chi2 = 4.85, P < 0.05), Enterobacteriaceae occupied the first place among the beta-lactamase detectable bacteria isolated from the delayed recovery group. There was no significant difference in detectable rate of kinds of bacteria isolated from recovery group and control group.

CONCLUSIONS

The main pathogens of patients with chronic rhinosinusitis are multiple drug resistance gram negative bacteria after operation, in which Pseudomonas aeruginosa occupies the first place. Gram negative bacteria are becoming the main opportunity pathogenic bacteria, which shows antibiotic resistance. microbial population of postoperative cavity from recovery group are becoming balanced.

Multiplex PCR for the detection of urogenital pathogens in mothers and newborns

Two duplex PCR assays were established for the detection of C. trachomatis (Ct), N. gonorrhoeae (GC), M. hominis (Mh), and U. urealyticum (Uu). These assays were used on clinical specimens obtained from women with Premature Rupture of Membrane or Post Partum Fever, from preterm infants, as well as from women with uneventful pregnancies and their babies delivered vaginally at term. The analytical sensitivity of the duplex PCR assays with internal controls incorporated is 7.0, 19.0, 5x10(3) and 7x10(2) genome copies per reaction for Ct, GC, Mh and Uu respectively. Specificity was demonstrated by the amplification of only target DNA in the presence of other organisms. Among 40 women with normal, at term, deliveries, there were 6 positives for Ct, 2 for GC and 1 for Uu. None of these women had signs of genital tract infection. The Mh/Uu PCR was positive in 11 of 40 PROM cases, with 7 women positive for Uu, 2 for Mh and 2 others for both organisms. Of 40 blood cultures taken from post-partum maternal infections, 6 were positive for Ct and 1 for Mh. Respiratory secretions from 30 premature neonates yielded 5 positives for Uu and one each for Mh and Ct. In contrast, there was only 1 positive result (for Mh) in 30 mature neonates. With 1 exception, all mycoplasma and ureaplasma positives were confirmed by culture and the concordance between paired tracheal aspirates and nasopharyngeal swabs from neonates was 96.7%. These results show the potential use of the duplex PCR assays for the diagnosis of maternal and neonatal disease caused by the four urogenital pathogens.

The use of a combined enrichment-filtration technique for the isolation of Campylobacter spp. from clinical samples

A combined non-selective enrichment-filtration technique was investigated for the isolation of Campylobacter spp. from clinical samples. In total, 479 samples were tested by direct culture, enrichment subculture and enrichment-filtration. The enrichment-filtration technique was used with both selective and non-selective media. Direct culture and enrichment subculture yielded 13 and seven isolates, respectively, while enrichment-filtration yielded 18 and 14 isolates on selective and non-selective agar, respectively. Thus, the combination of enrichment-filtration with selective agar produced a 38.5% increase in the number of isolates (p <0.05). All isolates were identified as Campylobacter jejuni.

[The effect of subglottic secretion drainage on prevention of ventilator-associated lower airway infection]

OBJECTIVE

To assess the influence of subglottic secretion drainage (SSD) on the morbidity of ventilator-associated pneumonia (VAP) in mechanically ventilated patients.

METHODS

All studied patients who received mechanical ventilation (MV) estimated for more than 48 hours were intubated with a special type endotracheal tube with a small-bore cannula in the wall for SSD. The patients were randomly divided into two groups receiving SSD (group A) and usual care (non-SSD, group B) respectively. Bacterial culture of samples from lower airway secretion taken regularly by Bagpipe Protected specimen brush were performed, and at the same time the subglottic secretion and scraping-pharynx specimen were collected for bacterial quantitative culture and antibiotic sensitivity test. The clinical data were recorded and the duration of MV, the length of stay in hospital and the time of occurrence of ventilator-associated airway infection (VAAI) and VAP were analyzed.

RESULTS

(1) In patients with MV < 5 days: The incidence of VAAI and VAP in group A (VAAI: 8.3% and VAP: 6.0%) was lower than those in group B (VAAI: 24.0% and VAP: 20.0%, P < 0.05). The onset of VAAI and VAP was delayed in group A [VAAI: (7.4 +/- 3.0) d and VAP: (7.7 +/- 3.2) d] as compared with group B [VAAI: (4.9 +/- 1.4) d and VAP: (4.6 +/- 2.1) d, P < 0.05]. There were no significantly statistic differences for hospital mortality, overall duration of mechanical ventilation, lengths of stay in the hospital between the two groups (P > 0.05). (2) The same organism as that previously found from subglottic secretion was isolated by PSB in 21.4% patients. (3) The concentration of bacteria in subglottic secretion from group A was decreased significantly as compared to that of group B. (4) Gram-negative bacilli were the main pathogens in the lower respiratory tract in the two groups. The dominant bacteria cultured in the lower airway secretions were Pseudomonas aeruginosa and Acinetobacter baumanii. There was no significant difference between the two groups in the spectrum of bacteria (P > 0.05).

CONCLUSIONS

(1) SSD reduced the incidence of VAAI and VAP in patients with MV < 5 d. The onset of VAAI and VAP was delayed in group A as compared with group B. The concentration of bacteria in the subglottic secretion was significantly reduced by subglottic secretion drainage. (2) Migration of the dominant bacteria of the subglottic secretion was one of the important factors for VALAI. (3) The dominant cultured bacteria in the lower airway secretion were gram-negative bacilli, most commonly Pseudomonas aeruginosa and Acinetobacter baumanii.

[Characteristic of clinical fluoroquinolone resistant isolates E. faecalis]

In presented study we have characterized phenotype of clinical E. faecalis strains, fluoroquinolone susceptibility and the presence of two potential virulence factors--hemolysin/cytolysin and gelatinase. Eighty three of E. faecalis strains were isolated from clinical samples from patients of five Warsaw hospitals. Susceptibility to 18 antibiotics was assessed by the disk diffusion method (ace. NCCLS). The MIC of ciprofloxacin was determineted by agar dilution method and the MIC of sparfloxacin and moxifloxacin by the E-test (AB BIODISK). Hemolysin production was evaluated on Columbia agar medium supplemented with 5% horse blood. Gelatinase production was determinated by using two different methods: I - on the Todd-Hewitt agar containing gelatin (30 g/l) and II--on the trypticase soy agar supplemented with 1,5% skim milk. Fourty nine (59%) of the 83 isolates E. faecalis were ciprofloxacin resistant and 14 (16,9%) were ciprofloxacin intermediate. The majority of E. faecalis strains (57,8%) were higly resistant to ciprofloxacin (MIC > or = 32 microg/ml). All of ciprofloxacin resistant E. faecalis isolates were cross-resistant to the other fluoroquinolones, as well. Production of hemolysin was more frequent among ciprofloxacin resistant E. faecalis strains. The dependence between gelatinase production and fluoroquinolone:resistance was not observed. Both investigated methods of gelatinase activity detection gave the same results and can be used exchangeably. Hemolytic strains were more frequently isolated from urine (47,8%), however gelatinase producing strains were more frequently isolated from wounds (31,6%).

Yersinia type III secretion: send in the effectors

Pathogenic Yersinia spp (Yersinia pestis, Yersinia pseudotuberculosis, and Yersinia enterocolitica) have evolved an exquisite method for delivering powerful effectors into cells of the host immune system where they inhibit signaling cascades and block the cells' response to infection. Understanding the molecular mechanisms of this system has provided insight into the processes of phagocytosis and inflammation.

[Microbiological evaluation of the vagina in women being screened for inflammatory and precancerous conditions of female genitalia]

The aim of this work was to study the microbiology of vaginal secretion in 3665 (19 to 72 year old) women investigated in the screening programme for inflammatory and malignant diseases. Microbiological examinations of the vaginal contents were carried out using direct preparations (Miller and Gram methods) and different media for cultures. Normal biocenosis (I and II grade of cleanliness) of the vagina was observed in 40.74% investigated patients. Abnormal biocenosis was classified as early, advanced and chronic state infections. In our study we present data on isolated strains of saprophytic organisms and pathogens including yeasts and Trichomonas vaginalis in early and chronic infections. There were homogeneous and mixed infections. The role of the physiological Lactobacillus species inhibiting development of pathogenic flora is suggestive of beneficial influence on the vaginal environment. Candidiasis of the vagina was identified in 11.35% examined women. High percentage Candida growth was found together with Lactobacillus vaginalis. It is noteworthy that trichomoniasis was less frequent compared to our previous reports. Totally we were able to isolate 2597 strains of bacteria. Bacteria type of abnormal biocenosis was found in 46.82%. The data from this study indicated that microbiological pictures (stained acc. to both Miller and Gram methods) are still of importance for the evaluation of vaginal contents. The second significant factor in microbiology of human vagina is the role of culture. This role of cultures for microbiologic studies of vaginal contents is beyond any doubt.

[The diversity of Staphylococcus aureus strains isolated in a Lisbon hospital over a 4-year period]

Over a 4-year period, 2020 Staphylococcus aureus strains isolated in Santa Maria Hospital were studied, 26.3% of which were methicillin-resistant (MRSA). The main specimens from which the strains were isolated included pus, blood and sputum/bronchial secretions. Isolation in blood cultures was the most common source among patients from medical units. Antimicrobial susceptibility studies showed that while in methicillin susceptible strains sensitivity to other antimicrobial agents (apart from penicillin resistance) was the rule, in MRSA strains there was resistance to most antibiotics. Only vancomycin was active against all strains. Phage typing showed that 75.5% of the strains were typable with phages at 100 x R.T.D. Among methicillin sensitive strains, a big diversity of phage patterns was observed, including phage groups I, II, III and V, as well as with phage association D11/95. The large majority of MRSA strains were lysed by group III phages, although several distinct patterns were observed. Within these strains, lysis by groups II and V phages was not observed. Plasmid profiling was the least discriminant issue in the characterization of these micro-organisms because most of the strains harboured only one plasmid (or none). These results showed that a dominant MRSA strain did not exist in this hospital, but rather several distinct strains. The importance, as well as the difficulties in controlling the spread of MRSA strains in the present conditions of high prevalence, are highlighted.

Bacteriology of bronchial secretions in non-tubercular lower respiratory tract infections

Fifty samples of bronchial secretions collected from patients of non-tubercular lower respiratory tract infections through fiberoptic bronchoscopy (FOB) were cultured both for aerobic and anaerobic organisms. Thirty-three (66%) samples yielded bacteria. Out of these, thirty were isolated in pure culture and from three, a mixed growth of aerobic and anaerobic micro-organisms was obtained. Aerobic bacteria were the predominant isolates. Stephylococcus aureus (10), pseudomonas (9) and streptococcus pneumoniae (8) were the major aerobic isolates. Ciprofloxacin was found to be the most effective drug against aerobes and metronidazole against anaerobes in vitro susceptibility tests.