Elevated uranium concentration and low activity ratio (234U/238U) in the Œuf river as the result of groundwater-surface water interaction (Essonne river valley, South of Paris Basin, France).

Uranium (U) is a naturally occurring radioactive heavy metal widely distributed on Earth. Noticeable elevated U concentration and low activity ratio (AR) were occasionally detected in headwater stream of the Essonne river (Seine Basin, France), the namely Œuf river. This paper aims at providing new insight on geogenic U features in headwater streams and examines the role of river-groundwater interaction. The Œuf river was sampled four times in 2020 to investigate the influence of heterogeneous geology and hydrological seasonality. The dissolved fraction of water samples was analyzed for a variety of chemical parameters (anion, major, minor and trace element concentrations, isotopes 234U and 238U). The Œuf river was shown to exhibit elevated U concentration up to 19.3 µg L-1 (exceeding by 100-fold the value of 0.19 µg L-1 known for riverine average) and low AR down to 0.41 (almost the third of the value expected in surface water, i.e., 1.17). The Œuf river got enriched in U when receiving groundwater from Beauce Limestone Aquifer System. High U concentration (above 15 µg L-1) was found in association with low AR (below 0.5) in the stream water when flowing in the outcrop zone of one BLAS unit. Taking advantage of changes in the stream flow conditions and the geochemical contrast between surface and ground waters, mixing volumes were calculated. This study first examined the potential of using U isotopes in combination with selenium as hydrogeochemical tracers of the river-groundwater continuum. In HWS, the aquifer discharge was shown to supply 12 to 59 % of the river water. This study demonstrates the key role played by the river-groundwater interaction on river water chemistry in small streams draining catchment with various geology setting. It also supports the use of combining redox sensitive trace elements to track the river-groundwater continuum.

Nomenclatural revision of Delphiniumsubg.Consolida (DC.) Huth (Ranunculaceae).

Recent molecular phylogenetic studies have indicated that Aconitella is embedded in Consolida, which in turn is embedded in Delphinium. We choose not to split the genus Delphinium (c. 300 species), as it is horticulturally and pharmaceutically important, by conserving a broad Delphinium by transferring the names from Consolida and Aconitella to Delphinium s.lat., and more precisely in the resurrected D.subg.Consolida. Including 58 species of Aconitella and Consolida within Delphinium causes fewer nomenclatural overall changes than do alternative schemes because most of the species of Aconitella and Consolida were once named under the name Delphinium. We present here the list of synonyms for the species once named under Consolida or Aconitella and gather the information relative to the types of these names. Two new combinations are provided, and 21 lectotypes are designated here.

A method for conducting simultaneous convergent tracer tests in multilayered aquifers.

Forced gradient tracer tests between two boreholes can be used to study contaminant transport processes at the small field scale or investigate the transport properties of an aquifer. Full depth tests, in which tracer samples are collected just from the discharge of the abstraction borehole, often give rise to breakthrough curves with multiple peaks that are usually attributed to different flow paths through the aquifer that can rarely be identified from the test results alone. Tests in selected levels of the aquifer, such as those between packer-isolated sections of the boreholes, are time consuming, expensive; and the identification of major transport pathways is not guaranteed. We present a method for simultaneously conducting multiple tracer tests covering the full depth of the boreholes, in which tracer sampling and monitoring is carried out by a novel multilevel sampling system allowing high frequency and cumulative sampling options. The method is applied to a tracer test using fluorescein conducted in the multilayered sandstone aquifer beneath the city of Birmingham, UK, producing six well-defined tracer breakthrough curves.

The serine protease inhibitor serpinE2 is a novel target of ERK signaling involved in human colorectal tumorigenesis.

BACKGROUND: Among the most harmful of all genetic abnormalities that appear in colorectal cancer (CRC) development are mutations of KRAS and its downstream effector BRAF as they result in abnormal extracellular signal-related kinase (ERK) signaling. In a previous report, we had shown that expression of a constitutive active mutant of MEK1 (caMEK) in normal rat intestinal epithelial cells (IECs) induced morphological transformation associated with epithelial to mesenchymal transition, growth in soft agar, invasion and metastases in nude mice. Results from microarrays comparing control to caMEK-expressing IECs identified the gene encoding for serpinE2, a serine protease inhibitor, as a potential target of activated MEK1. RESULTS: 1- RT-PCR and western blot analyses confirmed the strong up-regulation of serpinE2 expression and secretion by IECs expressing oncogenic MEK, Ras or BRAF. 2- Interestingly, serpinE2 mRNA and protein were also markedly enhanced in human CRC cells exhibiting mutation in KRAS and BRAF. 3- RNAi directed against serpinE2 in caMEK-transformed rat IECs or in human CRC cell lines HCT116 and LoVo markedly decreased foci formation, anchorage-independent growth in soft agarose, cell migration and tumor formation in nude mice. 4- Treatment of CRC cell lines with U0126 markedly reduced serpinE2 mRNA levels, indicating that expression of serpinE2 is likely dependent of ERK activity. 5- Finally, Q-PCR analyses demonstrated that mRNA levels of serpinE2 were markedly increased in human adenomas in comparison to healthy adjacent tissues and in colorectal tumors, regardless of tumor stage and grade. CONCLUSIONS: Our data indicate that serpinE2 is up-regulated by oncogenic activation of Ras, BRAF and MEK1 and contributes to pro-neoplastic actions of ERK signaling in intestinal epithelial cells. Hence, serpinE2 may be a potential therapeutic target for colorectal cancer treatment.

A new single-platform method for the enumeration of CD34+ cells.

Guidelines for flow cytometric enumeration of CD34(+) hematopoietic stem cells (HSC) recommend the use of a single-platform assay. The SCE kit has recently been commercialized by BD Biosciences. Results obtained with this newly available kit were compared with CD34(+) cell enumerations obtained in parallel with already commercialized diagnostic kits; fresh peripheral blood, apheresis, cord blood (CB) and bone marrow (BM) samples, as well as thawed apheresis and CB samples, were assayed. The SCE kit produced data for CD34(+) enumeration that correlate well with data produced with the older assays (r(2) > or = 0.9). Practical advantages were the ability to enumerate viable CD34 cells in all kinds of HSC products, the absence of bead pipetting (which decreases results precision) and a gating strategy complying with international recommendations. A major disadvantage was the absence of specific software for data analyses and presentation of results.

Constitutively active MEK1 is sufficient to induce epithelial-to-mesenchymal transition in intestinal epithelial cells and to promote tumor invasion and metastasis.

Constitutive activation of the MAP kinase kinase MEK1 induces oncogenic transformation in intestinal epithelial cells. Loss of cell-cell adhesion followed by the dissociation of epithelial structures is a prerequisite for increased cell motility and tumor invasion. This phenotypic switch is designated epithelial-to-mesenchymal transition (EMT). EMT also plays an important role in determining the dissemination of tumors. However, the role of MEK1 in intestinal EMT, tumor invasion and metastasis has not been elucidated. To determine the functions of activated MEK1 in intestinal tumorigenesis, we established intestinal epithelial cell lines that overexpress wild-type MEK1 (wtMEK) or activated MEK1 (caMEK). Our results indicate that expression of caMEK is sufficient to induce EMT as confirmed with the induction of N-cadherin, vimentin, Snail1 and Snail2, whereas a reduction in E-cadherin, occludin, ZO-1 and cortical F-actin was noted. The Snail1 and Snail2 promoter analyses revealed that Egr-1 and Fra-1, an AP-1 protein, are responsible for MEK1-induced Snail1 and Snail2 expression, respectively. Cells expressing activated MEK1 clearly acquired an invasive capacity when compared to wtMEK-expressing cells. Zymography studies confirmed elevated levels of MMP2 and MMP9 activities in media of caMEK-expressing cells. Importantly, cells expressing activated MEK1 induced tumors with short latency in correlation with their ability to induce experimental metastasis in vivo and to express factors known to promote colorectal cancer cell metastasis. In conclusion, our results demonstrate, for the first time, that constitutive activation of MEK1 in intestinal epithelial cells is sufficient to induce an EMT associated with tumor invasion and metastasis.

Clinical-grade preparation of human natural regulatory T-cells encoding the thymidine kinase suicide gene as a safety gene.

BACKGROUND: Human CD4+CD25+FOXP3+ natural regulatory T-cells (nTreg) have a great therapeutic potential for the induction of tolerance in allo-transplanted patients or for the control of severe auto-immune diseases. However, clinical-grade production of nTreg remains difficult to achieve because of the absence of a truly specific surface marker and of their low frequency that implies a need for their ex vivo expansion. Furthermore, safety issues should be taken into consideration due to the risk of either uncontrolled nTreg-induced immunosuppression or uncontrolled proliferation of autoreactive contaminating T-cells particularly in an auto-immune context. METHODS: We compared different clinical-grade conditions for immuno-magnetic selection and ex vivo expansion of nTreg. For safety, expanded cells were genetically modified with retroviral vectors co-expressing human CD90 and HSV1 thymidine kinase. The CD90 surface marker and thymidine kinase allow for selection and elimination of transduced cells by ganciclovir, respectively. RESULTS: We showed that (i) nTreg could be enriched in a one step using CD25 microbeads, were functionally suppressive and mainly FOXP3+; (ii) using anti-CD28- and anti-CD3-coated beads, interleukin-2 and rapamycin, nTreg were expanded 150-200-fold after 3 weeks. Under these clinical-grade conditions, they remained suppressive, and no major alteration of the TCR repertoire was observed; (iii) after efficient retroviral transduction and CD90 selection, nTreg maintained their suppressive activity; (iv) transduced nTreg could be eliminated by ganciclovir upon activation. CONCLUSIONS: The efficient procedure reported here for the preparation of nTreg, whose safety has been ensured, is now applicable for further clinical trials.

Predominance of type 1 (Th1) cytokine production in the liver of patients with HCV-associated mixed cryoglobulinemia vasculitis.

BACKGROUND/AIMS: Patients with hepatitis C virus (HCV) mixed cryoglobulinemia (MC) vasculitis have a higher mortality rate and more frequent incidence of cirrhosis than their cryoglobulin-negative counterparts. To compare the cytokine profile of liver-infiltrating T cells in HCV-infected patients with or without MC vasculitis. METHODS: Hepatic biopsy specimens were obtained from HCV infected patients with and without MC vasculitis. Using intracellular staining and flow cytometry, we assessed the ability of freshly isolated liver T cells from these biopsies to produce IFN-gamma, TNF-alpha, IL-2, IL-4, and IL-10 in response to stimulation with PMA and ionomycin. RESULTS: HCV-MC vasculitis patients compared to HCV-MC negative controls have an enhanced hepatic T cells production of Th1-type cytokines [i.e. TNF-alpha(30.3 +/- 13% vs. 15.5 +/- 5%, P = 0.01), IL-2 (20.2 +/- 9% vs. 10 +/- 4%, P = 0.01) and IFN-gamma (22.2 +/- 11% vs. 9.4 +/- 4%, P = 0.008)], whereas IL-10, a representative Th2-type cytokine, was significantly lower (7.2 +/- 4% vs. 17 +/- 7%, P = 0.01). CONCLUSIONS: T cell from the liver of HCV-MC vasculitis patients display a significantly augmented liver Th1 profile compared to MC-negative controls. This enhanced production of type-1 cytokines may account for a more severe course of liver disease.

Long-term persistence of clonally expanded T cells in patients with polymyositis.

Polymyositis is a CD8(+) T-cell-mediated disease. T-cell clonal expansions are observed at disease onset, but little is known about their persistence over time. Qualitative and quantitative spectratyping demonstrated that PM relapse features dramatically perturbed blood T-cell repertoires but is not associated with the emergence of new T-cell clones. It is striking that patients in remission also maintained all their T-cell repertoire abnormalities. The clonally expanded T-cells displayed a memory phenotype, expressed intracellular perforin, and dramatically responded to IL-2, showing a potential to be reactivated upon appropriate conditions. These results indicate that persistent T-cell clonal expansion is an important feature of polymyositis.

Pathogenic effects of anti-Fc gamma receptor IIIb (CD16) on polymorphonuclear neutrophils in non-organ-specific autoimmune diseases.

The receptors FcgammaRIIIb and FcgammaRIIa for the Fc portion of IgG are naturally expressed in polymorphonuclear neutrophils (PMN). Autoantibodies (Ab) against FcgammaRIIIb exist in patients with non-organ-specific disease. These may be categorized, based on the results of an indirect immunofluorescence (IIF) test for the detection of anti-membrane-bound FcgammaRIIIb autoAbs, and an enzyme-linked immunosorbent assay for that of soluble FcgammaRIIIb-recognizing autoAbs. The IIF+ autoAbs are not cytotoxic, and prolong the survival of the cells. The autoAb-triggered anti-apoptotic signal may be transduced through FcgammaRIIa and/or CD11b, the beta-chain of the neighboring complement receptor type 3. However, FcgammaRIIIb appears to be as competent as FcgammaRIIa, because the results obtained using the respective monoclonal Abs are additive. Soluble FcgammaRIIIb binds to CD11b and produces similar effects, suggesting that autoAb-stimulated FcgammaRIIIb can work in concert with CD11b. Anti-FcgammaRIIIb-conditioned supernatant of PMNs induces the transcription of messenger RNA for granulocyte colony-stimulating factor (CSF) and granulocyte-macrophage CSF, followed by the release of these anti-apoptotic factors. The delay in apoptosis is accompanied by a down-regulated expression of Bax. Thus, apoptosis of aged PMNs can be modulated by signaling through FcgammaRIIIb, which may occur in patients with PMN-binding anti-FcgammaRIIIb autoAbs.