Time-, Sex-, and Dose-Dependent Alterations of the Gut Microbiota by Consumption of Dietary Daikenchuto (TU-100)

Medications or dietary components can affect both the host and the host’s gut microbiota. Changes in the microbiota may influence medication efficacy and interactions. Daikenchuto (TU-100), a herbal medication, comprised of ginger, ginseng, and Japanese pepper, is widely used in Japanese traditional Kampo medicine for intestinal motility and postoperative paralytic ileus. We previously showed in mice that consumption of TU-100 for 4 weeks changed the gut microbiota and increased bioavailability of bacterial ginsenoside metabolites. Since TU-100 is prescribed in humans for months to years, we examined the time- and sex-dependent effects of TU-100 on mouse gut microbiota. Oral administration of 1.5% TU-100 for 24 weeks caused more pronounced changes in gut microbiota in female than in male mice. Changes in both sexes largely reverted to baseline upon TU-100 withdrawal. Effects were time and dose dependent. The microbial profiles reverted to baseline within 4 weeks after withdrawal of 0.75% TU-100 but were sustained after withdrawal of 3% TU-100. In summary, dietary TU-100 changed mouse microbiota in a time-, sex-, and dose-dependent manner. These findings may be taken into consideration when determining optimizing dose for conditions of human health and disease with the consideration of differences in composition and response of the human intestinal microbiota

Etude système de diodes lasers à verrouillage de modes pour la radio-sur-fibre en bande millimétrique

Ce travail de thèse s inscrit dans la recherche des solutions économiquementviables pour des réseaux personnels à hauts débits (plusieurs Gbps à plusieursdizaines de Gbps) opérationnels en bande millimétrique autour de 60 GHz. Aucas où ces réseaux servent un nombre élevé d utilisateurs, ils comprendront unemultitude d antennes afin d assurer l accès sans fil rapide. Afin de réduire aumaximum le coût d un module d antenne, les réseaux doivent fournir un signalanalogue à des porteuses millimetriques. Une solution prometteuse pour les systèmesde distribution qui correspond à ces besoins sont des structures à fibreoptique, laquelle permet une transmission à faibles pertes et à haute bande passante.On parle de l approche "radio-sur-fibre" (en anglais, radio-over-fiber). Laproblématique est de pouvoir générer et moduler un signal aux fréquences millimétriqueslors de la transmission optique - et ce avec des composant bas coûts.La technique utilisée dans le cadre de cette thèse est l emploi des diodes laser àverrouillage de modes. Ces derniers vont pouvoir générer des hautes fréquencestout en ne nécessitant qu une alimentation continue, et ils peuvent être modulésde manière directe ou externe. Les lasers à semi-conducteurs employés ici sontd une génération encore à l état d étude puisqu il s agit des lasers à boites (ouîlots) quantiques. Ces lasers ont montrés de très bonnes capacités à générer dessignaux électriques aux fréquences autour de 60 GHz, bien qu ayant encore, pourl instant, à une stabilité de fréquence (ou de phase) limitée. Dans le cadre des systèmesde communication opto/micro-ondes, peu de travaux approfondis ont étémenés sur ces structures.Au cours de cette thèse, plusieurs études ont été effectuées. La première portesur les propriétés générales d un système construit à partir de ce type de laser(puissances disponibles, figure de bruit, linéarité etc.). Une deuxième étude aété consacrée aux effets de la propagation des signaux dans les systèmes baséssur les lasers à verrouillage de modes, notamment de la dispersion chromatiquelaquelle a un effet considérable sur les distances de transmission. Les deux étudesmettent en avant l importance d une limitation du nombre de modes générés parla diode laser afin d optimiser non seulement le gain du lien et la puissance RFrécupérée, mais aussi la figure de bruit du système. Lors d une troisième étude, lastabilité en fréquence/phase s est révélée critique, car le bruit de fréquence/phaselimite la qualité de la transmission en introduisant un plancher d erreur mêmepour des rapports signal-a-bruit très élevés. Des différentes générations de lasersà boites (îlots) quantiques et à verrouillage de modes ont été testées. Le problèmedu bruit de fréquence et de phase persiste et ne peut pas être résolu en utilisantles techniques classiques comme les boucles à verrouillage de phase conventionnelles.Une solution pour ce problème a été développée pour les systèmes detransmission; elle permet simultanément un ajustement de fréquence supérieure(précision de quelques Hz à quelques kHz) à celle donnée par le processus de fabricationdes diodes lasers (précision de quelques GHz), ainsi qu une stabilisationde fréquence et de phase.This dissertation is related to the search for an economically sustainable solutionfor high data rate (several Gbps to several tens of Gbps) personal area networksoperating in the millimeter-wave region around 60 GHz. If such networks supplya large number of users, they need to encompass a multitude of antenna pointsin order to assure wireless access to the network. With the aim of reducing thecost of an antenna module, the networks should at best provide quasi "readyto-radiate" signals to the modules, i.e. at millimeter-wave carrier frequencies.Thanks to their low transmission loss and their high bandwidth, optical fiber distributionarchitectures represent a promising solution. The technique is referredto as the so-called "radio-over-fiber" approach whereby the analog radio signalwill be transported to the access point by an optical wave. The challenge herebyis the generation and modulation of an optical signal by a millimeter-wave radiosignal using preferably cost-efficient system components. The technique proposedherein is based on the use of mode-locked laser diodes which can generatesignals at very high frequencies under the condition of continuous current supply.Mode-locked laser diodes can be modulated both directly and externally. Thediodes employed in this work are based on so-called quantum dots (or quantumdashes); these are material structures which are themselves still subject to intensivephysical research. Signals at millimeter-wave frequencies (around 60 GHz)can easily be generated by such lasers. However, their frequency and phase stabilityis as yet limited. In the context of radio-over-fiber communication systems,these structures have not yet been studied in detail.In the course of this dissertation, several aspects are considered. A first systemstudy treats the basic properties of a system built from this type of laser source(available signal power, system noise figure, linearity etc.). A second study isdevoted to an investigation of propagation effects like dispersion, which considerablyinfluence the attainable transmission distances. An essential result of bothstudies is the importance of limiting the laser spectrum to a small number of lasermodes for an optimization of link gain, generated RF power, and system noisefigure. A third study deals with the limited frequency and phase stability whichturn out to be critical factors for transmission quality. The study of several generationsof quantum dot/dash lasers has revealed that the problems of frequencyand phase noise persist and cannot be solved using classical techniques involvinge.g. conventional phase-locked loops. In this dissertation, a solution is presentedwhich not only allows a more precise adjustment of the laser frequency (precisionin the order of Hz to kHz) than that given by the manufacturing process of thelaser (precision in the order of GHz), but also enables a stabilization of frequencyand phase.SAVOIE-SCD - Bib.électronique (730659901) / SudocGRENOBLE1/INP-Bib.électronique (384210012) / SudocGRENOBLE2/3-Bib.électronique (384219901) / SudocSudocFranceF

Downregulation of CXCR4 in Metastasized Breast Cancer Cells and Implication in Their Dormancy.

Our understanding of the mechanism of cancer dormancy is emerging, but the underlying mechanisms are not fully understood. Here we analyzed mouse xenograft tumors derived from human breast cancer tissue and the human breast cancer cell line MDA-MB-231 to identify the molecules associated with cancer dormancy. In immunohistological examination using the proliferation marker Ki-67, the tumors included both proliferating and dormant cancer cells, but the number of dormant cells was remarkably increased when they metastasized to the lung. In the gene expression analysis of the orthotopic cancer cells by a single-cell multiplex real-time quantitative reverse transcription PCR followed by flow cytometric analysis, restrained cellular proliferation was associated with downregulation of the chemokine receptor CXCR4. In the immunohistological and flow cytometric analyses, the expression level of CXCR4 in the metastasized cancer cells was decreased compared with that in the cancer cells in orthotopic tumors, although the expression level of the CXCR4 ligand CXCL12 was not reduced in the lung. In addition, the proliferation of the metastasized cancer cells was further decreased by the CXCR4 antagonist administration. In the ex vivo culture of the metastasized cancer cells, the expression level of CXCR4 was increased, and in the xenotransplantation of ex vivo cultured cancer cells, the expression level of CXCR4 was again decreased in the metastasized cancer cells in the lung. These findings indicate that CXCR4 is downregulated in metastasized breast cancer cells and implicated in their dormancy

Dormancy of breast cancer cells in the xenograft tumor-bearing mice.

<p>(A) Immunofluorescent images for the endothelial cell marker, CD31, and MDA-MB-231 breast cancer cells in the orthotopic tumor and metastatic lesions in the lung. The arrowhead indicates the metastatic tumor. Green: ZsGreen1; red: CD31; blue: nucleus. Scale bars: 100 μm for the low power field; 10 μm for the high power field. Representative images are shown. (B) Immunofluorescent images for Ki-67 in the MDA-MB-231 breast cancer cells in the orthotopic tumor and metastatic lesions in the lung. The arrowheads indicate the metastatic tumor lesions in the lung. Green: human leukocyte antigen (HLA)-A, B, C; red: Ki-67; blue: nucleus. Scale bars: 100 μm for the low power field; 10 μm for the high power field. Representative images are shown.</p

Downregulation of CXCR4 in dormant cancer cells in the human breast cancer patient-derived xenograft (PDX) model.

<p>(A) Heat map image of gene expression of 94 single breast cancer cells that were analyzed by the single-cell multiplex real-time quantitative reverse transcription PCR (RT-PCR) for 37 selected genes. Each of the squares filled with color shows the gene expression level of each single cell. Yellow indicates a high expression level, dark blue indicates a low expression level, and black indicates an undetectable level of gene expression. Green squares indicate the expression levels of <i>MKI67</i>, <i>GAPDH</i>, and <i>CXCR4</i>. Sky blue squares indicate cells showing undetectable expression levels of both <i>MKI67</i> and <i>CXCR4</i>. All cells showed an appropriate expression level of <i>GAPDH</i>. (B) Charts showing the relationship between the expression levels of <i>MIK67</i> and <i>CXCR4</i>. The results of the single-cell real-time quantitative RT-PCR were summarized. (C) Flow cytometric analysis of the expression level of cell surface CXCR4 and cell cycle of the cancer cells in the orthotopic tumors of the human breast cancer PDX. Representative histograms are shown.</p

Enhancement of the dormancy of the cancer cells in the lung by the inhibition of CXCR4.

<p>(A) Quantification of the expression levels of the <i>Cxcl12</i> mRNA in the orthotopic tumor and the lung tissues by real-time quantitative reverse transcription PCR. The expression levels of the mRNA were normalized to those of <i>Gapdh</i> as an internal standard (orthotopic tumor: n = 5; lung: n = 4). No significant difference was observed between these two tissues. (B) Immunofluorescent images for CXCL12 in the orthotopic tumor and the metastatic lesions in the lung. The anti-CXCL12 mAb recognized both mouse and human molecules. The immunofluorescence signal for human leukocyte antigen (HLA)-A,-B,-C was not detected under the fixation conditions used here, but it was observed under the different fixation conditions used in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0130032#pone.0130032.g001" target="_blank">Fig 1B</a>. Red: CXCL12; blue: nucleus. Scale bars: 50 μm. Representative images are shown. (C) Immunofluorescent images for Ki-67 in the metastatic lesions in the lung of the mice administered with or without AMD3100. Green: HLA-A, B, C; red: Ki-67; blue: nucleus. Scale bars: 100 μm. Representative images are shown. The area in the white boxes are magnified 2.5-fold in size and shown in the insets. The arrowheads indicate the Ki-67-positive metastatic cancer cells in the lung. (D) The rates of the Ki-67-positive MDA-MB-231 cells in the metastatic lesions in the lung. The number of the Ki-67-positive or negative cancer cells was manually counted in twelve high power fields, and the rate of the Ki-67-positive MDA-MB-231 cells were calculated. (** p<0.005).</p

Dynamic change of the expression level of CXCR4 responding to the change of tumor environment.

<p>(A) Microscopic examination of cells obtained from the lung and orthotopic tumor in the culture conditions. Images on the left show the bright field view and images on the right show the fluorescent view. Green cells in the fluorescence view indicate breast cancer cells. Cells with no fluorescence around the cancer cells are the non-cancer cells. Scale bar: 200 μm. Representative images are shown. (B) Flow cytometric analysis of CXCR4 of the breast cancer cells obtained from the lung tissues in the culture condition. The histogram with blue color indicates cancer cells in the lung <i>in vivo</i>, purple indicates <i>ex vivo</i> cultured cancer cells obtained from the lung, and red indicates cancer cells in the orthotopic tumor <i>in vivo</i>. Representative histograms are shown. Cells in the light green colored area are cells with a high expression level of cell surface CXCR4. (C) Percentage of the <i>ex vivo</i> cultured cancer cells with a high expression level of cell surface CXCR4 in the low (70–80% confluent) and high (100% confluent) cell densities. At least three analyses were performed at each time point. Asterisks indicate the significant difference between the two groups. (D) The schema and histograms of the xenotransplantation experiment of the <i>ex vivo</i> cultured cancer cells originally obtained from the orthotopic tumor and the lung. Histograms show the expression level of cell surface CXCR4 of the cancer cells obtained from the orthotopic tumor and the lung of the mice that were xenotransplanted with the <i>ex vivo</i> cultured cancer cells originally obtained from the orthotopic tumor or the lung. The red colored histograms indicate the cancer cells obtained from the orthotopic tumors, and blue colored histograms indicate the cancer cells obtained from the lung. Representative histograms are shown. (E) Summary of our findings. The change of the tumor environment causes the change of the expression level of CXCR4. This change facilitated the tumor growth.</p