6C). If the inhibition of L-plastin phosphorylation is a main mode of

action of dexamethasone, then it should also interfere with F-actin stabilization upon antigen recognition. To address this point, we analyzed the effects of dexamethasone on the F-actin content in T cells stimulated with superantigen-bearing APCs using MIFC. The F-actin content in untreated or dexamethasone preincubated T cells was similar if T cells were left unstimulated (Fig. 7A and B). In contrast to the unstimulated situation, the F-actin content was higher in stimulated control T cells (MPI=108.26) compared with dexamethasone-treated and -stimulated T cells (MPI=77.56) (Fig. 7A and B). This finding correlate well to the data observed with cells expressing 5A-LPL since dexamethasone inhibits L-plastin phosphorylation (compare Figs. 4 and 6). Given that L-plastin phosphorylation is mandatory for the inhibitory selleck screening library Sirolimus solubility dmso effect of dexamethasone on actin polymerization and immune synapse formation, the expression

of a phospho-mimicking mutant of L-plastin should at least in part revert the phenotype triggered by dexamethasone. An exchange of serine to glutamic acid at position 5 (5E-LPL) was shown to mimic phosphorylated L-plastin 10. We compared T cells expressing EGFP or 5E-LPL regarding its sensitivity toward dexamethasone. In primary human T cells, the expression level of 5E-LPL was relatively low. We therefore used (by gating) only EGFP-positive T cells of the EGFP or 5E-LPL transfections with the same expression level for that comparison (Fig. 7C). Interestingly, while the increase in F-actin following Cepharanthine T cells stimulation with SEB-loaded APCs was inhibited by dexamethasone in EGFP-expressing T cells, 5E-LPL-expressing T cells showed no inhibition in the F-actin content

in stimulated T cells (Fig. 7D). Moreover, the immune synapse formation was not affected in 5E-LPL-expressing T cells that were pretreated with dexamethasone, whereas EGFP-expressing T cells showed a significantly reduced formation of the immune synapse (Fig. 7E, left graph). Interestingly, 5E-LPL expression could only rescue the disturbed LFA-1 accumulation (Fig. 7E, middle graph), but not the defective CD3 enrichment (Fig. 7E, right graph). Together, these experiments show that inhibition of L-plastin phosphorylation is an important step mediating the disturbed LFA-1 enrichment in dexamethasone-treated T cells. Deliberate and well-regulated immunosuppression is beneficial in treating autoimmune diseases or preventing transplant rejection. One class of frequently used immunosuppressive drugs are glucocorticoids. Here, we introduce a so far unknown mechanism by which the glucocorticoid dexamethasone induces immunosuppression, namely the inhibition of L-plastin phosphorylation, which eventually leads to impaired immune synapse maturation.

The authors declare no conflicts of interest. “
“The host response to different helminth species can vary and have different consequences for helminth persistence. Often these differences are generated by changes in the dynamics and intensity of the immune components against parasites with distinct life history strategies. We examined the immune response of rabbits to primary infections of the gastrointestinal nematodes Trichostrongylus retortaeformis and Graphidium strigosum under controlled conditions for 120 days post-challenge. Results showed that

KU-60019 rabbits developed a robust and effective immune response against T. retortaeformis and abundance quickly decreased in the duodenum and was completely cleared in the remaining sections of the small intestine within 4 months. Infected individuals exhibited an initial strong inflammatory response (IFN-γ), IL-4 expression also increased and was coupled to a rapid serum and mucus IgG and IgA and eosinophilia. Strong IL-4, serum IgA and IgG responses and eosinophilia were also observed

against G. strigosum. However, parasite abundance remained consistently high throughout the infection, and this was associated with relatively low mucus antibodies. These findings suggest that immunity plays a key role in affecting the abundance of these nematodes, and different immune mechanisms are involved in regulating the dynamics of each infection and their long-term persistence in free-living host populations.

The host immune response represents one of the most powerful lines of defence against helminth infections, and, not surprisingly, hosts Selleckchem SCH 900776 have developed a large variety of immune components and functions to recognize and target different parasite life stages and their products (e.g. eggs and excretory/secretory compounds). The immune system can control the initial establishment of infective larvae, regulate their development and influence the survival, fecundity and clearance of the mature stages (1–9). Yet, the immune response to different helminth species is highly variable such that it may appear rapid and effective against one parasite species and slow to develop and inadequate for protection against another species. To gain a better appreciation of the strategies adopted by both parties and Fossariinae how they optimize their conditions, i.e. a healthy host and a parasite with high fitness, we need to understand the immunological processes that affect host–parasite interactions and see if they equally explain parasite dynamics in free-living animal populations and laboratory systems. We have been investigating the epidemiology of infection of two gastrointestinal nematodes, Trichostrongylus retortaeformis and Graphidium strigosum, in a free-living population of European rabbits (Oryctolagus cuniculus) by examining the relationship between host age and parasite intensity (10,11).

This shift is further influenced by changes in acid-base status, osmolality, glucose and insulin concentration and catecholamine activity. The rapid decline in plasma potassium concentration, which occurs in the early stages of dialysis, unfavourably alters the QT interval (a marker of ventricular recovery time) and increases the risk of arrhythmias.10 Redaelli et al.11 demonstrated that modelling dialysate potassium so as to maintain a constant selleck compound blood-to-dialysate potassium gradient of 1.5 mmol/L throughout dialysis decreased premature ventricular ectopy, particularly during

the first hour of the dialysis. Hypokalaemia increases vascular resistance and has been implicated in post-dialysis rebound hypertension. Dolson

et al.12 demonstrated a greater incidence of post-dialysis hypertension in patients dialysed against a dialysate potassium of 1 mmol/L compared with 3 mmol/L. Current evidence suggests modelled or higher dialysate potassium should be considered in patients with underlying cardiac disease (particularly those prone to arrhythmias) and those troubled by post-dialysis rebound hypertension. Calcium is central to contraction of vascular and cardiac smooth muscle. Increased serum calcium levels in haemodialysis patients have been associated with greater all-cause and cardiovascular mortality risk, as well as with poor mental health.13 The prescription of dialysate calcium needs to take into account the effects this website of calcium on both the skeleton and the vasculature. There are advantages and disadvantages to both lower and higher dialysate calcium (Table 1). Lower dialysate calcium allows for increased doses

of both calcium-based phosphate binders and vitamin D, with consequent suppression of parathyroid hormone (PTH). However, as demonstrated by Argiles et al.,15 dialysate calcium less than 1.25 mmol/L may result in negative calcium balance and subsequent Nintedanib (BIBF 1120) stimulation of PTH. The same study showed a reversal of this hyperparathyroidism when patients were subsequently treated with vitamin D. Another disadvantage of lower dialysate calcium is an increased incidence of intradialytic hypotension and decreased stroke volume.16 Thus, low dialysate calcium should be avoided in patients prone to intradialytic hypotension. Severi et al.17 demonstrated that a lower dialysate calcium (resulting in negative calcium balance) when accompanied by end-dialysis hypokalaemia predicted critical QTc prolongation. This suggests that this combination should be avoided, at least in patients with cardiac disease. Kyriazis et al.18 compared 18 patients on low (1.25 mmol/L), medium (1.5 mmol/L) or modelled dialysate calcium (1.25 mmol/L during the first 2 h, then 1.75 mmol/L during the last 2 h). Intradialytic hypotensive events were reduced only with modelled calcium dialysate (See Fig. 1).

The association between nephrosclerosis and systemic atherosclerosis is not clear. In this study, we investigated the Dactolisib concentration association between CA-IMT and nephrosclerosis in a group of kidney transplant donors. Methods:  Forty seven potential kidney transplant donors were included. CA-IMT was measured by B-Mode ultrasonography. Kidney allograft biopsy samples were obtained during the transplantation operation and chronic glomerular, vascular and tubulointertitial changes were semiquantitatively scored according to the Banff classification. Results:  Mean age was 52 ± 12 years and 55% of the cases were younger than 55 years. Mean CA-IMT was 0.74 ± 0.19 mm and 48% had IMT values > 0.75 mm. Chronicty

index was ≥5 in 55% of the cases. Chronicity index was higher in cases older than 55 years. Age and CA-IMT were significantly check details correlated with chronic vascular changes and chronicity index. CA-IMT > 0.75 mm had a 46% sensitivity and 90% specificity to predict nephrosclerosis. Positive and negative predictive values were 85% and 57%, respectively. Conclusion:  Aging leads to detrimental changes in every part of the vasculature of the human body. CA-IMT is correlated with the level of nephrosclerosis. Measurement of CA-IMT reflects nephrosclerosis especially

in older patients. “
“Dialysate prescription is evolving as new technology allows greater opportunity to alter dialysate constituents throughout dialysis, providing scope for tailored prescription for an individual patient. The intention of modelling or profiling Tau-protein kinase is to improve the tolerability of dialysis and long-term patient outcomes. This approach can be applied to both electrolytes and water. Despite these advances in technology, benefits of modelling have not been demonstrated consistently. This review examines the use of individual prescription and modelling of dialysate sodium, ultrafiltrate, potassium, calcium, magnesium, bicarbonate and phosphate. With older and

increasingly complex patients, the potential benefits of individual prescription of dialysate have gained more relevance. In most dialysis centres dialysate is prepared, centrally, to provide a predetermined standard composition. Individual dialysate prescription may involve setting concentration of each solute at the start of dialysis and adjustment of the concentration of some solutes throughout the dialytic period, so-called modelling or profiling of the dialysate. The need to improve both intradialytic and interdialytic morbidities and long-term outcomes has driven the use of individualized prescription. The goal of this review is to summarize current evidence for individualizing dialysate composition, with a focus on conventional, thrice weekly dialysis. Considerable effort has been focussed on determining the optimum concentration of dialysate sodium.

coli O157:H7, Gemella sanguinis, Granulicatella spp., Morganella morganii ssp. morganii, Pantoea ananatis, Pantoea eucalypti, Raoultella terrigena, Shigella dysenteriae, Shigella flexneri and Shigella sonnei were also identified. Among fungi, Candida carpophila, Candida humilis, Candida milleri, Kazachstania barnettii and Pichia guilliermondii were additionally identified. At macroscopical observation (Fig. 3), both the outer (Fig. 3a) and the inner surfaces, obtained by bisecting stents’ segments along their longitudinal

axis (Fig. 3b), were found to be more or less covered or filled by a yellow brownish, soft and heterogeneous material, respectively. In Fig. 4, common nonmicrobial sludge components have been observed Dabrafenib by SEM including dietary fibers (Fig. 4a), as a result of duodenal reflux, and crystals that were tentatively identified as calcium PD-0332991 price bilirubinate and calcium palmitate, respectively (Fig. 4b and c). SEM observation of longitudinal sections of partially occluded stents (Fig. 5) revealed the early phase of sludge formation (Fig. 5a). At a higher magnification,

it was possible to recognize coccoid bacterial cells (Fig. 5b), rod-shaped bacteria (Fig. 5c) and fungal cells (Fig. 5d). Fig. 5c clearly shows the typical appearance of sludge in direct contact with the bile flow as indicated by the mucous material in which bacteria are immersed and grow as a biofilm. As observed by SEM (Fig. 6), in the cross-section of a stent segment, the dehydration procedures for sample observation frequently caused a cleavage (Fig. 6a) at the interface between the biliary sludge content and the stent lumen. In Fig. 6b, the ‘sludge Pembrolizumab in vivo side’ of this cleavage is shown in which both coccoid cells and their imprints are observed, while in Fig. 6c, a portion of sludge matrix, devoid of bacteria, but still attached to the lumen surface, can be observed. The sludge detachment from the inner stents’ lumen caused by the dehydration procedure evidenced,

in almost all samples, clusters of microbial cells closely bound to the polymeric stent surface (Fig. 6d, e and f). All the 19 isolated anaerobic strains were investigated for their ability to produce slime in vitro. Among the 12 Gram-negative anaerobic isolated strains tested for slime production, those belonging to the species Bacteroides fragilis, Fusobacterium necrophorum, Prevotella intermedia and Veillonella spp. were strong slime producers, while the strain of Prevotella bivia was a weak producer and the three Bacteroides strains of B. capillosus, Bacteroides distasonis and Bacteroides oralis were nonproducers (Table 3). With respect to the six Gram-positive anaerobic strains isolated, five were strong producers (Clostridium baratii, Clostridium perfringens, Peptostreptococcus magnus, Veillonella spp. and F.

In contrast, L. (V.) braziliensis-infected DCs failed to up-regulate the activation markers, but exhibited an enhancement in their ability to produce TNF-α that may contribute to the local control of the parasite (23). L. (V.) braziliensis infection efficiently triggers innate immune response in DCs, helping the priming of adaptive immune response for parasite clearance, as both parasite and antigen-carrying

DCs displayed an activated phenotype despite amastigote showing higher infectivity and potential to stimulate DCs when compared with promastigote CB-839 nmr (24). Concerning the CD4+ T-cell expression, a distinct profile was noted between the two Leishmania species studied: BALB/c mice infected with L. (L.) amazonensis presented a high number of CD4+ T cells in the lesions at both 4th and 8th weeks PI (P < 0·05), just when the infection had developed a severe disease, whereas the animals infected with L. (V.) braziliensis showed a higher number (P < 0·05) of these cells only at the 8th weeks PI, just when the infection seemed to be controlled. Thus, the elevated CD4+ T-cell response in the L. (L.) amazonensis infection was preferentially characterized by a Th2 response, because higher

levels of IL-4 and IL-10 were observed in this group compared to that of the L. (V.) braziliensis infection, in which these cytokines were not detected at 8th weeks PI. In this regard, it is interesting to mention that despite Qi et al. (2001) (25) showing CP-690550 concentration that draining lymph node cells of BALB/c mice infected with L. (L.) amazonensis may produce both Th1 Methane monooxygenase (IFN-γ) and Th2 (IL-4 and IL-10) cytokine profiles, the magnitude of Th2 response, linked to a higher expression of IL-4 and IL-10 cytokines, is responsible for the success of L. (L.) amazonensis infection when the levels of IFN-γ are low. In contrast,

despite the CD4+ T-cell response in the skin lesions of BALB/c mice infected with L. (V.) braziliensis showing a higher density only at the 8th weeks PI, this expression was just accompanied not only with the control of infection but also with high levels of IFN-γ, thus suggesting that the CD4+ T-cell response in L. (V.) braziliensis infection was preferentially characterized by a Th1 response. Moreover, IFN-γ is an important cytokine for the macrophage activation, leading to parasite elimination through the production of metabolites oxygen and nitrite. Thus, reduced levels of this cytokine could affect the efficiency of parasite elimination and the control of the infection (26). In this way, it should be stressed that our experiments showed that iNOS expression in the skin lesions of animals infected with L. (L.) amazonensis remained on the same level of the control group, whereas in the skin lesions of animals infected with L. (V.) braziliensis, there was a significant increase at both 4th and 8th weeks PI, suggesting an efficient T-cell immune response activation in the L. (V.

These effects were entirely or predominantly absent for media derived from indomethacin-containing cultures. Addition of medium from Th17 cultures lacking MSCs had no suppressive effect and was not influenced by indomethacin. Reversal of the MSC suppressive effect on primary Th17 differentiation

was also demonstrated using NS-398, a selective COX-2 inhibitor (Fig. 5C). Next, MSCs were FACS-purified from 4-day Th17 co-cultures and subjected to qRT-PCR and Western blotting (Fig. 5D) using COX-1 and COX-2-specific reagents. As shown, specific up-regulation of COX-2 in MSCs co-cultured with CD4+ DAPT cell line T cells under Th17-skewing conditions was observed at mRNA and protein level. Blocking/inhibition experiments carried out to examine the role of other candidate mediators (NO, IDO, EPZ-6438 order IL-10, CCL2) yielded negative or minimally significant results (data not shown). Overall, these experiments supported a conclusion that the primary mechanism of Th17 suppression from both naïve and memory-phenotype CD4+ T cells was the production of a prostanoid mediator due to induced up-regulation of COX-2 in MSCs following direct contact between MSCs and activated T cells. As PGE2 has been reported to mediate multiple immune suppressive effects of MSCs 1, 2, 7, 9, 12, 18, supernatants from MSC/Th17 co-cultures of 6–72 h duration were analysed for PGE2 concentration with

relevant controls (Fig. 6A). Neither MSCs cultured alone nor CD4+ T cells cultured with or without Th17-inducing reagents generated high PGE2 levels. In contrast, MSC/T-cell co-cultures under Th17 differentiating PD184352 (CI-1040) conditions had significant accumulation of PGE2 over 12–72 h. Interestingly, increased PGE2 production

was also observed from 12 to 24 h in MSC/T-cell co-cultures lacking Th17-inducing factors but levels declined again between 48 and 72 h. In additional experiments, MSCs were formally confirmed to be the predominant source of PGE2 in MSC/Th17 co-cultures by sorting individual cell populations following 18 h of co-culture then re-plating them for an additional 18 h and quantifying PGE2 concentration in the resulting supernatants (Supplementary Figs. S5, S6 and S7A). PGE2 concentration increased in a dose-dependent manner in Th17 cultures involving direct contact with MSCs but not in Transwell® co-cultures at the same MSC:CD4+T-cell ratios (Supplementary Fig. S8A). Additionally, PGE2 concentrations in supernatants from fibroblast/Th17 co-culture supernatants were not different to those of control Th17 cultures (Supplementary Fig. S8B). It was next determined whether MSC suppressive effects on primary Th17 cultures were mediated by PGE2. Addition of purified PGE2 was associated with a dose-dependent inhibition of T-cell proliferation and IL-17A production (Fig. 6B) as well as of CD25 surface expression and IL-17A production following re-stimulation (data not shown).

, Foster City, CA, USA). Assumptions and formulation.  The PLN and each islet are assumed to be well-mixed, spatially homogenous compartments. Each islet bin, as described above, contains the same model architecture. Differences in simulated behaviours in islets of different bins result from sequential and progressive lymphocyte infiltration of different islets and islet bins, leading to different

degrees of accumulated infiltrate, Trichostatin A price local inflammation and damage at a given time. Common functions represented in all compartments include mediator synthesis, cellular proliferation, apoptosis and activation. Each of these functions are regulated by cell contact and soluble mediators with the following basic approach: (i) a baseline rate is Rucaparib in vitro assigned if data suggest a constitutive activity; (ii) additional stimulatory effects are assumed to be additive; (iii) regulators that synergize or amplify the impact of another are treated as potentiating them and represented as having multiplicative effects; (iv) inhibitory

effects are represented as fractional reductions in baseline and/or stimulated effects as indicated by the data; and (v) an upper limit may be imposed, such as when the rate is proportional to the fraction of cells involved (e.g. proliferation) and saturates at 100% involvement. The likelihood of cell contact within a compartment is a function of the relative numbers of each cell type within the total cellular population. Mediator concentrations in each compartment are a function of the synthesis rate (i.e. ng/1e6 cells/h), the number of mediator-producing cells, mediator half-life and the compartment volume. Because the effect of each regulator

is dependent on its concentration/activity, Venetoclax a standard dose–response curve was employed to describe the relationship between the regulator and its effects (Fig. 3). Published data were used to define the effective concentration range and the maximum effect. If the effective concentration range had not been published, the available data were used to define the saturating concentration and a three-log range of dose-sensitivity is assumed. Parameterization.  Parameter values were derived directly from (or calculated to be in agreement with) published data wherever quantitative data were available. Preference was given to NOD mouse data. If unavailable, data from other mouse strains, other animal species or human cells were used. The determination of the rate of tumour necrosis factor (TNF)-α synthesis by activated CD8+ T lymphocytes from Utsugi et al. [79] is a relevant illustration of data usage. They reported TNF-α production by NOD CD8+ T cell clones stimulated with islet cells. In all similar cases where parameters were extracted/calculated from specific literature, the references are cited in the location within the model where the parameter was used. Thus, all directly derived parameters are referenced.

3B). These observations suggested that activation of the TLR2 signaling pathway conferred DCs the ability to diminish T1D in vivo. DCs play a crucial part in activating not only effector T cells, but also Tregs, and previous work has shown that CD4+CD25+ Tregs can be expanded with DCs in vitro and used to treat autoimmune diabetes in vivo 35, 36. Based on our results thus far, we assessed whether TLR2-mediated stimulation in vitro might expand Tregs capable of diminishing T1D Small molecule library clinical trial in vivo. DCs and CD4+CD25+ T cells were purified from 9-wk-old NOD mice and cultured in the presence or absence of P3C. After 6 days, the DCs were depleted

from the culture, and the Tregs were counted and their phenotype assessed. CD4+CD25+ Tregs cultured with DCs and stimulated Belnacasan through TLR2 in vitro had expanded five-fold, whereas cells cultured

in the absence of P3C showed no expansion in culture (Fig. 4A). Consistent with previous observations by others 29, 30, Foxp3 expression was reduced in TLR2-stimulated Tregs, although not completely lost, and surface expression of CD25 was increased (Fig. 4B), although modestly. Expression of CD127 and most notably PD-L1 was also increased on the surface of P3C-stimulated Tregs. Addition of an anti-CD3 antibody to the culture media further promoted the expansion of the Tregs but did not affect them in terms of expression of Foxp3 or CD127 (data not shown). Interestingly, P3C-mediated expansion of Tregs was associated

with IL-10 production and depended on the presence of DCs stimulated through TLR2 (either before or during culture with the Tregs) (Supporting Information Fig. 1). We then assessed the capacity of CD4+CD25+ T cells cultured with DCs and P3C to modulate T1D in vivo. While CD4+CD25+ Tregs cultured with DCs in the absence of P3C could diminish diabetes upon injection into 9-wk-old NOD mice, stimulation through TLR2 significantly ameliorated the tolerogenic function of these cells, which conferred efficient reduction of the disease (Fig. 4C). In sum, exposure of CD4+CD25+ Tregs to DCs stimulated through TLR2 promoted their Fossariinae expansion and markedly increased their tolerogenic function in T1D in vivo. Based on our results thus far and our previous observations in virally mediated prevention of T1D 12, we addressed whether TLR2 neutralization in vivo concomitant to LCMV infection of NOD mice might affect the capacity of the virus to prevent autoimmunity. Anti-TLR2 blocking mAbs were administered to prediabetic, 9-wk-old NOD mice along with LCMV and again 5 days later, and development of diabetes was monitored. We observed that LCMV delayed the onset of diabetes but failed to significantly reduce disease incidence when administered to NOD mice in the context of TLR2 blockade (Fig. 5).

, 1999; Al-Hasani et al., 2001). One strain, designated EC13334, harbored aah but not aid. The aah gene encodes the autotransporter adhesin heptosyltransferase, which modifies Aid through the addition of heptose residues (Benz & Schmidt, 2001). Heptose modification is essential for the adhesive functions of Aid; thus, EC13334 is most likely deficient in adhesin involved in diffuse adherence (AIDA) function. Our findings do not rule

out, however, a possible role Selleckchem HSP inhibitor for AIDA adhesin in the pathogenicity of some EAST1EC strains. Ha et al. (2003) also reported that among 45 AIDA-positive strains, five harbored astA. Apart from the adhesive genes, hlyA, which encodes α-hemolysin, was found in three strains. The α-hemolysin is a pore-forming cytolysin and a known virulence factor in extraintestinal pathogenic E. coli such as UPEC (Menestrina et al., 1994). The α-hemolysin has frequently MG-132 molecular weight been detected in EAggEC and DAEC strains (Jallat et al., 1993; Suzart et al., 1999). Furthermore, the results of Elliott et al. (1998) indicated that α-hemolysin could

also act as a diarrheal toxin, and α-hemolysin in porcine diarrheal strains enhances virulence (Smith & Linggood, 1971). Escherichia coli carrying α-hemolysin are significantly associated with human diarrhea, particularly in young children (Gunzburg et al., 1993). The irp2 gene was found in 24 strains. This gene encodes the bacterial siderophore yersiniabactin. The genes encoding yersiniabactin-mediated iron-uptake system are clustered in a chromosomal pathogenicity island, and its presence is correlated with the virulence of highly pathogenic Yersinia (Schubert et al., 1998; Carniel, Bcl-w 2001). The ability to acquire iron is crucial for survival of bacteria in the human intestine, which is an iron-limited environment; therefore the presence of yersiniabactin may be of benefit to EAST1EC strains during an infection. Interestingly, strains harboring additional virulence

genes other than lpfA often shared irp2. The presence of a particular set of virulence genes that includes irp2 and astA may be characteristic of a subset of EAST1EC that is diarrheagenic in humans. We did not detect ldaG, pet, daa or cdtB in any of the EAST1EC strains. In fact, the presence of these genes has not been confirmed other than in a few particular E. coli pathotypes. Virulence gene profiling of 35 EAST1EC strains isolated over a period of 3 years revealed subsets of shared virulence genes associated with other E. coli pathotypes, mainly EHEC and EAggEC. Among these virulence genes, lpfA, iha, pic, hlyA, and irp2 were contained within chromosomes, often flanked by the insertion sequence elements (Johnson & Lior, 1987; Vial et al., 1988; Schubert et al., 1998; Czeczulin et al., 1999; Henderson et al., 1999; Tarr et al., 2000; Doughty et al., 2002; Kahali et al., 2004).