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61.
The ectoparasitic mite Dorsipes caspius n. sp. (Heterostigmata: Podapolipidae) belonging to the platysmae species group collected from the beneath elytra of Pterostichus (Lyrothorax) caspius (Menetries) (Coleoptera: Carabidae) in northern Iran, is described. This is the first record of species of the platysmae group from the Middle East. Keys to adult and larval female stages of world species of the platysmae group are provided. The host range of all species of the genus and the distribution of all representatives of the group are discussed. 相似文献
62.
Onur Basak Maaike van de Born Jeroen Korving Joep Beumer Stefan van der Elst Johan H van Es Hans Clevers 《The EMBO journal》2014,33(18):2057-2068
Cycling Lgr5+ stem cells fuel the rapid turnover of the adult intestinal epithelium. The existence of quiescent Lgr5+ cells has been reported, while an alternative quiescent stem cell population is believed to reside at crypt position +4. Here, we generated a novel Ki67RFP knock-in allele that identifies dividing cells. Using Lgr5-GFP;Ki67RFP mice, we isolated crypt stem and progenitor cells with distinct Wnt signaling levels and cell cycle features and generated their molecular signature using microarrays. Stem cell potential of these populations was further characterized using the intestinal organoid culture. We found that Lgr5high stem cells are continuously in cell cycle, while a fraction of Lgr5low progenitors that reside predominantly at +4 position exit the cell cycle. Unlike fast dividing CBCs, Lgr5low Ki67− cells have lost their ability to initiate organoid cultures, are enriched in secretory differentiation factors, and resemble the Dll1 secretory precursors and the label-retaining cells of Winton and colleagues. Our findings support the cycling stem cell hypothesis and highlight the cell cycle heterogeneity of early progenitors during lineage commitment. 相似文献
63.
Vlada S. Rozova Ayad G. Anwer Anna E. Guller Hamidreza Aboulkheyr Es Zahra Khabir Anastasiya I. Sokolova Maxim U. Gavrilov Ewa M. Goldys Majid Ebrahimi Warkiani Jean Paul Thiery Andrei V. Zvyagin 《PLoS computational biology》2021,17(7)
Epithelial-mesenchymal transition (EMT) and its reverse process, mesenchymal-epithelial transition (MET), are believed to play key roles in facilitating the metastatic cascade. Metastatic lesions often exhibit a similar epithelial-like state to that of the primary tumour, in particular, by forming carcinoma cell clusters via E-cadherin-mediated junctional complexes. However, the factors enabling mesenchymal-like micrometastatic cells to resume growth and reacquire an epithelial phenotype in the target organ microenvironment remain elusive. In this study, we developed a workflow using image-based cell profiling and machine learning to examine morphological, contextual and molecular states of individual breast carcinoma cells (MDA-MB-231). MDA-MB-231 heterogeneous response to the host organ microenvironment was modelled by substrates with controllable stiffness varying from 0.2kPa (soft tissues) to 64kPa (bone tissues). We identified 3 distinct morphological cell types (morphs) varying from compact round-shaped to flattened irregular-shaped cells with lamellipodia, predominantly populating 2-kPa and >16kPa substrates, respectively. These observations were accompanied by significant changes in E-cadherin and vimentin expression. Furthermore, we demonstrate that the bone-mimicking substrate (64kPa) induced multicellular cluster formation accompanied by E-cadherin cell surface localisation. MDA-MB-231 cells responded to different substrate stiffness by morphological adaptation, changes in proliferation rate and cytoskeleton markers, and cluster formation on bone-mimicking substrate. Our results suggest that the stiffest microenvironment can induce MET. 相似文献
64.
L Flancbaum D N Brotman J C Fitzpatrick T Van Es E Kasziba H Fisher 《Life sciences》1990,47(17):1587-1593
Carcinine (beta-alanylhistamine) was synthesized in vitro from histamine and beta-alanine. It was detected quantitatively using an HPLC method previously described for the quantification of the related compounds histamine, histidine, carnosine and 3-methylhistamine. Carcinine was identified in several tissue of the rat, guinea pig, mouse and human, and was then shown to be metabolically related in vivo to histamine, histidine, carnosine and 3-methylhistamine through radioisotopic labeling. The results demonstrate that carcinine may be concurrently quantitated using the same HPLC method as that used to measure histamine, histidine, carnosine and 3-methylhistamine. These findings suggest a role for carcinine in the carnosine-histidine-histamine metabolic pathway and in the mammalian physiologic response to stress. 相似文献
65.
Dr. Jan J. Blankert Yvonne Muizert Paul J. Oljans Leendert A. van Es Leendert C. Paul 《Immunogenetics》1985,22(6):625-635
Previous studies have shown that immunization of MAXX rats with spleen and lymph node cells from the MHC-identical BN strain results in the formation of antibodies that react with the renal endothelial alloantigen Eag-1. In the present study, the reactivity of MAXX anti-BN sera was further characterized. No reactivity of the antisera was detected with unseparated spleen, lymph node, thymus and bone marrow cell suspensions, peripheral blood, or cells obtained from lung lavages. The antisera did, however, react with splenic macrophages, as well as with peritoneal granulocytes and macrophages from BN, BMA, BN.1L, and PVG rats. Genetic studies revealed that the antigen, provisionally designated Pag-1, segregates independently of Eag-1, the RT1 complex, sex, and the hooded and albino traits. Pag-1 appears to be absent in the kidney, since absorption of MAXX anti-BN sera with BN kidney homogenates did not remove the reactivity against Pag-1, and antisera raised against BN peritoneal cells did not bind with the renal endothelium. Pag-1 is expressed on bone marrow-derived cells, since peritoneal cells from lethally irradiated MAXX rats that were reconstituted with bone marrow cells from BN donors reacted with MAXX anti-BN sera, whereas peritoneal cells from BN rats reconstituted with MAXX bone marrow did not.Abbreviations used in this paper BSA
bovine serum albumin
- CDC
complement-dependent microcytotoxicity
- MHC
major histocompatibility complex
- PBS
phosphate-buffered saline 相似文献
66.
In‐line monitoring of amino acids in mammalian cell cultures using raman spectroscopy and multivariate chemometrics models
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Hemlata Bhatia Hamidreza Mehdizadeh Denis Drapeau Seongkyu Yoon 《Engineering in Life Science》2018,18(1):55-61
The application of PAT for in‐line monitoring of biopharmaceutical manufacturing operations has a central role in developing more robust and consistent processes. Various spectroscopic techniques have been applied for collecting real‐time data from cell culture processes. Among these, Raman spectroscopy has been shown to have advantages over other spectroscopic techniques, especially in aqueous culture solutions. Measurements of several process parameters such as glucose, lactate, glutamine, glutamate, ammonium, osmolality and VCD using Raman‐based chemometrics models have been reported in literature. The application of Raman spectroscopy, coupled with calibration models for amino acid measurement in cell cultures, has been assessed. The developed models cover four amino acids important for cell growth and production: tyrosine, tryptophan, phenylalanine and methionine. The chemometrics models based on Raman spectroscopy data demonstrate the significant potential for the quantification of tyrosine, tryptophan and phenylalanine. The model for methionine would have to be further refined to improve quantification. 相似文献
67.
68.
69.
V. V. Gavrilov A. G. Es’kov A. M. Zhitlukhin D. M. Kochnev S. A. Pikuz I. M. Poznyak S. N. Ryazantsev I. Yu. Skobelev D. A. Toporkov N. M. Umrikhin 《Plasma Physics Reports》2018,44(9):820-827
Results are presented from experimental studies of a pulsed source of soft X-ray (SXR) emission with photon energies in the range of 0.4–1 keV and an output energy of 2–10 kJ. SXR pulses with a duration of 10–15 μs were generated in collisions of two plasma flows propagating toward one another in a longitudinal magnetic field. The plasma flows with velocities of (2–4) × 107 cm/s and energy contents of 70–100 kJ were produced by two electrodynamic coaxial accelerators with pulsed gas injection. Nitrogen and neon, as well as their mixtures with deuterium, were used as working gases. The diagnostic equipment is described, and the experimental results obtained under different operating conditions are discussed. In particular, X-ray spectroscopy was used to study the high-temperature plasma produced in a collision of two plasma flows. The observed intensities of spectral lines are compared with the results of detailed kinetic calculations performed in a steady-state approximation. The calculations of the nitrogen and neon kinetics have shown that the electron temperature of a nitrogen plasma can be most conveniently determined from the intensity ratio of the resonance lines of He- and H-like nitrogen ions, while that of a neon plasma, from the intensity ratio between the resonance line of He-like Ne IX ions and the 3p?2s line of Li-like Ne VIII ions. In the experiments with plasma flows containing nitrogen ions, the electron temperature was found to be ≈120 eV, whereas in the experiments with plasma flows containing neon ions, it was 160–170 eV. 相似文献
70.
Gene polymorphisms of macrophage migration inhibitory factor affect susceptibility to chronic hepatitis B virus infection in an Iranian cohort
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Bita Moudi Zahra Heidari Hamidreza Mahmoudzadeh‐Sagheb Mohammad Hashemi 《Microbiology and immunology》2016,60(6):390-396