As a result of its speed and potential sensitivity, nucleic acid

As a result of its speed and potential sensitivity, nucleic acid amplification via polymerase chain reaction (PCR)-based protocols appear as an attractive alternative.33 However, as Bennett pointed out,34 the lack of a reference standard other than blood culture is a significant impediment to the development of standardised assay. Specifically, it is hard to decide if the detection of Candida nucleic acids in blood culture-negative samples is a false-positive result or reflects a lower threshold

of detection. In addition, the substantial resource requirements and costs of a high-quality PCR laboratory limit the immediate use of PCR in the individual patient, thus diminishing its time advantage Selleckchem Lenvatinib when compared with culture-based diagnostics. Evidence built up in the last couple of years unequivocally indicates that the time point of initiation

of adequate antifungal therapy greatly impacts the outcome of Candida bloodstream infections in terms of hospital mortality. This was most impressively demonstrated in patients with septic shock: in a large sample, Kumar et al. [35] retrospectively found a crude hospital mortality of 87% in patients with Candida spp. as the causative agent compared to 52% in patients with bacterial pathogens selleck inhibitor in cohorts with similar baseline APACHE II score and age. They showed that the median time to effective therapy was 35 h in fungal septic shock compared to only 6 h in bacterial septic shock. If the data were adjusted for time from onset of hypotension to start of appropriate antimicrobial therapy, there was no difference in mortality of the two cohorts. This clearly demonstrates that the excess mortality in fungal septic shock is attributable to delays of effective antifungal therapy. In patients receiving antifungal therapy within 2 h after onset of hypotension, the mortality rate was only 19% were compared

to 94% if antifungal therapy was delayed by 12 h. Mortality increased by approximately 8% G protein-coupled receptor kinase per hour of delay. By the way, these data may serve as a strong indicator of the close correlation between the time of initiation of antifungal treatment and mortality rates of severe Candida sepsis. Similarly, the same group showed that appropriateness of initial therapy, i.e. coverage of the causative pathogen by the first administered drug, was associated with increased survival in Candida septic shock with 5–10-fold reductions in hospital mortality for both C. albicans and C. non-albicans infections.36 As pointed out, blood cultures remain the backbone of diagnosis of fungal bloodstream infection. Incubation times to positivity tend to be substantially longer with Candida spp. when compared with bacterial pathogens because of the generation times of several hours in contrast to <1 h for bacteria commonly involved in septic infections.

The observed end points were CVD

death, myocardial infarc

The observed end points were CVD

death, myocardial infarction, unstable angina or ischaemic stroke during a follow-up period of the average of 519 days (range 138–924 days) [14]. The study design was approved by the Ethics Committee of Helsinki University Central Hospital, Helsinki, Finland, and an informed consent was obtained from each subject enroled in the study. Radiographic dental status.  The dental status of the patients was acquired by panoramic tomography taken after the admission to the hospital, as previously described [15]. The presence or absence of erupted teeth and periodontal breakdown was recorded. Patients were divided into three groups: edentulous, without periodontitis (later in the text referred to as non-periodontitis) MG132 and with periodontitis. Periodontal breakdown was established when the distance from the cementoenamel junction to the alveolar bone margin was more than 4 mm. The non-periodontitis patients had no radiographic evidence of periodontal breakdown [15, 16]. Serum analysis and sampling time points.  Baseline serum samples were

taken within 48 h of the arrival to the hospital. Follow-up samples were taken after 1 week, 3 months and 1 year of hospitalization owing to the ACS event. IgG and IgA antibody levels to A. actinomycetemcomitans and P. gingivalis were measured by multiserotype ELISA [17]. The inter-assay coefficient of variation was 6.6% and 6.2% for A. actinomycetemcomitans IgG and IgA assays, selleck compound and 5.3% and 5.6% for P. gingivalis

IgG and IgA assays, respectively. The cut-off limits for seronegatives and seropositives were 2.0 EU and 5.0 EU for IgA- and IgG-class antibody levels, respectively, corresponding to the mean + 1.5 × SD Sunitinib purchase of periodontally healthy individuals [17]. Serum IgG and IgA levels to human HSP60 were determined by ELISA [18]. The inter-assay coefficient of variation was 4.6 for IgA and 5.2% for IgG assays, respectively. In all antibody assays, the intra-assay coefficient of variation was 2.0–2.5%. High-sensitive C-reactive protein concentrations were quantified by immunoturbidometry [19]. All serum samples were taken after overnight fasting, and the laboratory analyses were performed in a blind fashion. Salivary bacterial analysis.  Salivary samples were taken at baseline within 48 h of arrival to the hospital. Paraffin-stimulated samples were collected and processed as previously described [14]. Aggregatibacter actinomycetemcomitans and P. gingivalis were PCR-amplified using species-specific primers as previously described [20]. Chromosomal DNA isolated from A. actinomycetemcomitans ATCC 43718 and P. gingivalis W50 strains were used as positive controls and sterile water as negative controls in each series of PCR reactions, which were performed blinded for the study groups. Statistics.  The significance of differences was analysed by Mann–Whitney U-test, Chi-square test and Wilcoxon signed ranks test.

As shown in Fig  5, Flt3L gene expression was significantly incre

As shown in Fig. 5, Flt3L gene expression was significantly increased in MPPs from Fli-1∆CTA/∆CTA B6 LY2606368 mice compared with that cultured from wild-type B6 mice. The expressions of STAT3, Csf1 and Flt3

were higher in MPPS from Fli-1∆CTA/∆CTA B6 mice compared with that cultured from wild-type B6 mice, though the difference was not statistically significant (Fig. 5). To assess whether Fli-1 directly or indirectly regulates the expression of Flt3L, we analysed the promoter region of the Flt3L gene. There are 15 putative Fli-1 binding sites in the promoter region of the mouse Flt3L gene. We designed 15 pairs of primers to cover these sites, and a ChIP assay was performed to examine if Fli-1 binds to the promoter of Flt3L. The primers used are listed in Table 1. We examined the expression of Fli-1 and Flt3L in MS1 endothelial cell lines by RT-PCR and found that both Fli-1 and Flt3L are expressed in the cell line (data not shown). After immunoprecipitation by a Fli-1-specific antibody with cross-linked protein/DNA complexes from MS1 cell lines, two Fli-1 sites were significantly enriched with specific Fli-1 antibodies as detected by PCR amplification and compared with normal rabbit IgG controls (Fig. 6). These results clearly indicate Fli-1 can directly bind to the promoter of the Flt3L gene and probably regulate the expression of Flt3L. Fli-1 transcription factor regulates the differentiation

and development of haematopoietic lineages, especially megakaryocytic and erythrocytic lineages.[28-30] We previously demonstrated that Fli-1 modulates B-cell development and is implicated in autoimmune VX-770 in vitro disease.[22, 26, 27, 31] We report here that Fli-1 also plays an important role in mononuclear phagocyte

development. We found that Fli-1∆CTA/∆CTA mice had significantly increased populations of HSCs and CDPs in BM compared with wild-type littermates (Fig. 1). Therefore, Fli-1 is likely to play an important role in regulating HSC and CDP development. Expression of Fli-1 clearly affects the HSC population and lack of the CTA domain in Fli-1 resulted in the increase of the HSC population. Previous studies have demonstrated that expression of Fli-1 affects development and differentiation Thymidine kinase of megakaryocytes, erythrocytes, neutrophils and monocytes in Fli-1-deficient or Fli-1 heterozygous mice.[28, 29] Complete Fli-1 deficiency in HSCs resulted in a decrease in neutrophilic granulocyte and monocyte populations in mice.[29] In this report, we used Fli-1ΔCTA/ΔCTA mice with expression of a truncated Fli-1 protein, lacking the C-terminal transcriptional activation domain.[24] Cell proportion and absolute cell number of pDCs, cDCs, pre-cDCs and macrophages in the spleen from Fli-1∆CTA/∆CTA mice were significantly increased when compared with wild-type littermates (Fig. 2). The splenic cDC population can be subdivided into three groups according to their surface markers.

6 Cystatin-C is particularly sensitive at detecting changes in ki

6 Cystatin-C is particularly sensitive at detecting changes in kidney function when renal impairment is mild,7 and is better than creatinine for assessment of acute kidney injury due to its shorter half-life.8 Some other potential biomarkers of renal function are also worthy of note. Uric acid is normally excreted through the kidney but circulating levels increase during https://www.selleckchem.com/products/rgfp966.html renal impairment in CKD. Animal model studies have shown that hyperuricaemia activates the renin-angiotensin

system, induces oxidative stress and reduces renal function.9 Increased levels of serum uric acid have been detected in patients with CKD by colorimetric assay and predict a greater risk of end-stage renal disease.9 Urinary levels of angiotensinogen detected by ELISA have been reported to be a specific index of the intrarenal renin-angiotensin system and correlate with blood pressure and glomerular filtration rate in CKD.10 Therefore, urine angiotensinogen appears to be a potential biomarker of renal function in kidney diseases that are dependent on hypertension.

The fractional excretion of magnesium (FE Mg) is considered to be a measure of tubular function because tubules normally reabsorb magnesium filtered by glomeruli.11 Levels of magnesium can be measured in serum and urine by atomic absorption spectroscopy. Elevations in the FE Mg are thought to indicate the loss of peritubular capillary flow resulting from tubulointerstitial damage.11 Oxidative stress is known to play a pathological role in animal models of CKD.12 Increased oxidative stress is Enzalutamide also present in patients with moderate to severe CKD;13 however, further longitudinal and intervention studies are required to help define the role of oxidative stress in the development of human

CKD. Some serum and urine biomarkers have been shown to reliably measure the level of renal oxidative stress in patients and animal models. During oxidative stress, oxidized guanine in cellular DNA is spliced out by DNA repair enzymes, releasing a metabolically stable product 8-hydroxy-2-deoxyguanosine (8-OH-dG) into the urine. Increased levels of 8-OH-dG can be detected in urine by ELISA during CKD.14 Peroxidation of lipids also occurs during oxidative stress, resulting in the formation of 8(F2a)-isoprostane Selleck Cobimetinib and 4-hydroxy-2-nonenal. Levels of 8-isoprostane and 4-hydroxy-2-nonenal can be measured in serum or urine by ELISA or HPLC and are elevated in CKD.15–17 In addition, renal oxidative stress produces peroxynitrite that nitrates protein tyrosine residues to form stable 3-nitrotyrosine peptides. A recent study has indicated that levels of 3-nitrotyrosine peptides can now be accurately measured in serum or urine using liquid chromatography and mass spectroscopy, which may prove to be useful for assessing both oxidative and nitrosative stress in kidney disease.

For other genetic immune defects, including CVID, the pathogenesi

For other genetic immune defects, including CVID, the pathogenesis of autoimmunity remains more obscure, although recently genetic studies have provided some illumination. However, the heterogeneity in both pathogenesis and clinical complications in CVID makes these investigations challenging. This paper is part of a supplement supported by an unrestricted grant from Grifols. The author received payment for the preparation of this article and attendance at the symposium in which it was presented. This work was supported by grants from the National Institutes of Health, AI 101093,

AI-467320, and AI-48693. “
“Neospora caninum is an Apicomplexa parasite that in the last two decades was acknowledged as the main pathogenic www.selleckchem.com/products/z-vad-fmk.html agent responsible for economic losses in the cattle industry. In the present study, the effectiveness of intranasal immunization with N. caninum Temozolomide order membrane antigens plus CpG adjuvant was assessed in a murine model of intragastrically established neosporosis. Immunized mice presented a lower parasitic burden in the brain on infection

with 5 × 107 tachyzoites, showing that significant protection was achieved by this immunization strategy. Intestinal IgA antibodies raised by immunization markedly agglutinated live N. caninum tachyzoites whereas previous opsonization with IgG antibodies purified from immunized mice sera reduced parasite survival within macrophage cells. Although an IgG1 : IgG2a ratio < 1 was detected in the immunized mice before and after infection, indicative of a predominant T helper type 1 immune response, no increased production of interferon-γ was detected in the spleen or mesenteric lymph nodes of the immunized mice. Altogether, these results show that mucosal immunization with N. caninum membrane proteins plus CpG adjuvant protect against intragastrically

established neosporosis and indicate that parasite-specific mucosal and circulating antibodies have a protective role against this parasitic infection. “
“The aim of this study is to evaluate the expression and regulation of proprotein convertase subtilisin/kexin (PCSK) 6, which is known to be an important factor in the production this website of bone morphogenetic protein (BMP) cytokines in human ovary. The localization of PCSK 6 protein in normal human ovaries was examined by immunohistochemistry. Human granulosa cells (GC), obtained from 34 patients undergoing ovarian stimulation for in vitro fertilization, were cultured with BMP-2, BMP-6, BMP-7, BMP-15, growth differentiation factor (GDF)-9, and activin-A with or without FSH. PCSK 6 mRNA expression level was evaluated by quantitative real-time reverse transcription and polymerase chain reaction (RT-PCR).

38 To date, however, there are insufficient data to determine whe

38 To date, however, there are insufficient data to determine whether cure rates differ significantly between the repeat retropubic and transobturator routes, and whether complication rates are higher after secondary than primary MUS procedures. Use of a re-adjustable sling for recurrent SUI with sphincteric deficiency is currently under investigation. Use of the Remeex (Neomedic, Barcelona, Spain) re-adjustable sling (Fig. 1) showed that, after

3 years, 109 of 125 (87.2%) women were continent under stress after initial surgery, including 49 of 55 (84%) with recurrent SUI and 60 of 70 (85.7%) with ISD.44 Moreover, 19 of these patients showed additional benefit from Apitolisib concentration a subsequent re-adjustment. The rate of infection of the re-exposed varitensor during adjustment was lower, while the development of de novo overactivity (8%) was similar to results observed with the other sling type. A prospective study of the AMI adjustable suburethral sling (Agency for Medical Innovation GmbH, 6800 Feldkirch, Austria) (Fig. 245) implanted through the retropubic route in 25 patients with recurrent urodynamic SUI showed that 21 of the patients were urodynamically continent after 12 months.46 A recent study described the use of a transobturator

crossover re-adjustable sling as a salvage procedure for failed anti-incontinence MK-1775 supplier procedures (Fig. 3).47 This SAFYRE t plus sling (Promedon, Cordoba, Argentina) consists of a monofilament polypropylene mesh between two self-anchoring Florfenicol columns. The procedure is performed by creating a spiral sling for better circumferential coaptation

of the urethra. Moreover, silicone washers are used in the genitofemoral fold at the level of the clitoris, both to improve fixation and facilitate later adjustments. Re-adjustments were easily performed under local anesthesia by moving the washers until there was no urine leakage during valsalva maneuver. After 12 months, the overall cure rate was 93.7% (15/16), with only one patient requiring re-adjustment. During surgery, however, one patient experienced a urethral perforation, which was resolved by closing the urethral operation. The adjustable continence therapy (ACT) device consists of two adjustable balloons, each attached to an injection port placed subcutaneously in the labia majora (Fig. 4).48 After 6 years, 68% of patients remained dry.49 The pubovaginal sling has shown success rates ranging from 50 to 90% in the treatment of women with persistent or recurrent SUI. A trial of the pubovaginal sling in patients with all types of SUI divided patients into simple and complex groups, with mean numbers of prior incontinence surgeries of 0.78 and 3.1, respectively.50 After 1-year follow-up, SUI was cured in 183 women (73%) and improved in 48 (19%). After a >10-year follow-up in 20 women, the success rate was 95%.

The use of

The use of click here statins in treating KD may be beneficial due to its observed immunomodulatory properties, including the inhibition of T cell proliferation and cytokine production as well as inhibiting MMP-9 production, suggesting that statins may have benefit beyond that of cholesterol-lowering in Kawasaki disease. More study is needed to determine the safety and efficacy of this class of therapeutic agents in young children. This study was funded by operating grants from the Canadian Institutes of Health Research (MOP-81378)

and the Heart and Stroke Foundation of Canada (T6365). R.S.M.Y. is a recipient of an Investigator Award from the Arthritis Society of Canada and BWM is the holder of the CIBC World Markets Children’s Miracle research chair. All authors have no conflicts of interest. Fig. S1. Cytotoxicity assay. Mouse vascular smooth muscle cells (MOVAS) cells were cultured [Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% heat-inactivated fetal bovine serum (FBS), sodium pyruvate, non-essential amino acid, selleckchem 2 mM L-glutamine

and 10 mM HEPES] for 6 h in a 96-well culture plate with 25 ng/ml recombinant mouse tumour necrosis factor (TNF)-α (eBioscience, San Diego, CA, USA), and with either various atorvastatin concentrations or of the drug vehicle, dimethyl sulphoxide (DMSO). After the incubation period, cytotoxicity was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) using a commercial kit, following the manufacturer’s protocol (Roche Applied Science, Mannheim, Germany). Open and solids bars represent cultures in the presence of atorvastatin and corresponding concentrations of DMSO, respectively. “
“Peripheral blood monocyte (PBM) subsets play different Histone demethylase roles in inflammatory response and tissue remodelling.

The aim of this study was to investigate how allergen challenge affects the number of circulating PBMs in Dermatophagoides pteronyssinus (Dp) allergic patients (Dp-APs). Among 34 Dp-APs challenged, in 22 patients significant bronchoconstriction was demonstrated [responders (Rs)], while in 12, only upper respiratory symptoms were seen [non-responders (NRs)]. Twelve healthy, non-atopic subjects were used as controls (HCs). Expression of CD14, CD16 and CCR4 was evaluated by flow cytometry on the whole-blood samples before (T0), 6 h (T6) and 24 h (T24) after the challenge. Plasma concentrations of CCL2, CX3CL1 and CCL17 were evaluated using ELISA. At T0, the mean percentage of CD14++ CD16+ PBMs in Rs (35.4%; 95%CI 26.9–43.9%) was significantly greater than in HCs (14.6%; 95%CI 7.3–21.8%; P = 0.006) and in NRs (17.5%; 95%CI 9.6–25.4%; P = 0.001). The baseline number of CD14++ CD16+ PBMs correlated with airway hyper responsiveness (AHR) (r = −0.507; 95%CI −0.834 to −0.432, P < 0.001). At T24, the number of CD14++ CD16+ PBMs significantly decreased in Rs but not in NRs and the numbers inversely correlated with plasma CCL17 concentration.

The necessity of using at least two doses in early vaccination

The necessity of using at least two doses in early vaccination

is also recommended by other authors (Siegrist, 2001; Truszczyñski & Pejsak, 2007). It is unlikely that lack of specific lymphocyte proliferation in some pigs from group 3 (vaccinated at 8 weeks) was a result of immaturity of the immunological system at this age, especially when we look at the results obtained in group 5 (vaccinated at 1 and 8 weeks). A strong proliferative response observed in group 6, 2 weeks after vaccination as well as at 20 weeks of life, in contrast to group 4, confirmed that Anti-infection Compound Library vaccination at the first week of life may initiate formation of T-memory cells and that these cells are responsible for a stronger response at the next contact with antigen. These data show that, although some component of their immune system may not be fully competent at such an early age as 7 days, neonate piglets were nevertheless capable of mounting an effective memory T-cell response following vaccination with live ADV. As shown in groups 3 and 5, ADV sensitization of lymphocytes was evoked by vaccination despite the presence of MDA, but the persistence of such early induced immunity is not sufficient for the whole production cycle. This may suggest that the number of long-lived postvaccinal memory T

cells could be lower than in animals vaccinated later or when no maternal antibodies existed. Similar results were shown after analysis of IFN-γ secretion in response to recall antigen. Besides its antiviral activity, IFN-γ plays a role in https://www.selleckchem.com/products/MLN8237.html immunomodulatory functions, such as the increase of the expression of SLA I (which enhances the cytotoxic activity) and SLA II (which favors cell cooperation in antigen presentation and antibody production). The production of IFN-γ by PBMC in response to recall antigen (groups 3 and 5) was only significant 2 weeks after vaccination. In cultures of PBMC derived from

animals from groups 3 and 5 at 20 weeks of life, the production of this cytokine was lower than before, whereas in groups 2, 4 and 6 (vaccinated in the face of lower MDA titers) there was no significant decrease in secretion. IL-4 is a cytokine that induces differentiation before of naïve helper T cells to Th2 cells. This cytokine stimulates antibody production (mainly IgG1 isotype). In the present study there was no excretion of this cytokine after or without ADV stimulation. Similar results were obtained by Fisher et al. (2000). Those authors evaluated the cytokine gene expression in PBMC of naïve and immune pigs. IL-4-specific mRNA was not detectable either in nonstimulated or in ADV-exposed porcine PBMC. The results of the present study indicate that early priming of T cells with ADV-MLV in the face of MDA could be successful, but that to obtain a long-term proliferative response at least one booster dose of vaccine, given at the proper time, is required.

3–5,44 Hence, the diurnal suppression of Tres cytokine secretion

3–5,44 Hence, the diurnal suppression of Tres cytokine secretion by nTreg might, in part, be driven by the cellular circadian clock of nTreg via yet-unknown pathways. Therefore, the analysis of the circadian Caspase activity clock in T cells should be addressed in future studies. Besides the cellular circadian clock, the hormonal priming of T cells in vivo could be another mechanism

for the diurnal rhythm of cytokine secretion by Tres.13 To investigate this possible mechanism we analyzed the hormone levels from all subjects and performed a multiple linear regression analysis. We found a negative correlation between cortisol serum levels and T-cell cytokine secretion. Furthermore, we demonstrated in vitro that a 2 hr pre-incubation with physiological daytime levels of cortisol decreased cytokine secretion. This CT99021 cost is in line with in vitro data published by other investigators demonstrating an immunosuppressive effect of cortisol.8,26,30,45–47 A positive correlation

was found between melatonin and prolactin serum levels and T-cell cytokine secretion. Whereas we could show in vitro that pre-incubation of Tres with prolactin increased the secretion of IL-10 but decreased that of IL-2 by Tres, we were unable to demonstrate this effect for melatonin. Prolactin was described to display immune-stimulatory functions in vitro, whereas conflicting data are published for melatonin.27,30,48,49 We also observed increased IFN-γ after prolactin pre-incubation Thymidylate synthase but this effect was not significant, as previously described by Matera et al. and Dimitrov et al.29,30 However, Matera et al. investigated unstimulated T cells while we used polyclonally stimulated Tres. Dimitrov et al. studied the percentage of IFN-γ-producing T cells in whole blood which were stimulated with PMA/ionomycin in the presence of prolactin. By contrast, we pre-incubated T cells with prolactin, performed

the assays (αCD3 stimulated) without prolactin and measured the concentration of IFN-γ in the supernatant. Despite these different approaches, our observations are broadly similar to these other reports.29,30 Our findings on the effect of melatonin are in line with other investigators who did not observe stimulatory effects of melatonin in vitro.49 We could not confirm the proposed Th1-enhancing effect of melatonin in vitro but these published data are from in vivo experiments in mice and conflicting data have also been published.50 In any case, one can speculate, from the effects of cortisol and prolactin, that the hormonal milieu could be one mechanism of the diurnal rhythm of cytokine secretion by Tres. The suppressive activity of nTreg on cytokine secretion by Tres did not correlate with the serum levels of any of the hormones.

In addition, an rsmY rsmZ double mutant shows enhanced biofilm fo

In addition, an rsmY rsmZ double mutant shows enhanced biofilm formation compared with the wild type, suggesting that both genes jointly influence biofilm formation. Recently, a significant upregulation of the transcriptional activity stemming from intergenic regions was noted when B. cenocepacia J2315 biofilms were treated with oxidizing agents (Peeters et al., 2010). Treatment with H2O2 or NaOCl resulted in the upregulation of 37 and 56 intergenic regions, respectively, compared with untreated biofilms. Protein Tyrosine Kinase inhibitor Several of these intergenic regions were located in the close proximity of genes with a

similar expression pattern, suggesting cotranscription. However, other intergenic regions demonstrated markedly different expression patterns compared with their flanking genes and the basal expression levels of several of these regions were high. Several of these putative sRNAs were previously predicted using an in silico approach (Coenye et al., 2007), while others were found to be differentially expressed in B. cenocepacia grown in sputum (Drevinek et al., 2008)

or under soil-like conditions (Yoder-Himes et al., 2009). While the function of most of these putative sRNAs remained elusive, one had a marked similarity to the 6S RNA gene consensus structure, indicating its potential involvement in regulating gene expression. Dabrafenib Traditionally, microarrays are used to identify changes in gene expression in high-throughput analyses, but there are several drawbacks associated with their use. Probably the most relevant drawback is that this approach is inherently biased (i.e. you can only measure what is known and hence represented on the array). This can be circumvented using high-throughput parallel sequencing (RNA sequencing). This novel, unbiased, approach will not only reveal changes in the expression level of protein-coding

genes, but will also lead to the discovery of changes in sRNA expression. Several sequencing technologies are currently available, including pyrosequencing (454 sequencing) and Illumina why ‘sequencing-by-synthesis’ (Mardis, 2008; Shendure & Hanlee, 2008; Petterson et al., 2009). These techniques present a vast improvement over microarray-based transcriptome analysis, but still rely on the generation of cDNA before sequencing, which may be the source of various types of errors. Ozsolak et al. (2009) recently described an entirely novel approach called ‘direct RNA sequencing’. Direct RNA sequencing is based on Helicos BioSciences’ ‘True Single Molecule Sequencing’ technology and allows the sequencing of femtomole quantities of RNA without the need for prior cDNA generation. This approach would allow the unbiased whole-transcriptome analysis of a low number of cells and would provide a snapshot of the response in various parts of the biofilms.