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81.
Arsen Osipov Alex B.Blair Juliane Liberto Jianxin Wang Keyu Li Brian Herbst Yao Xu Shiqi Li Nan Niu Rufiaat Rashid Ding Ding Yanan Liu Zaiqi Wang Christopher L.Wolfgang Richard A.Burkhart Daniel Laheru Lei Zheng 《癌症生物学与医学(英文版)》2021,(1):206-214
Objective:Pancreatic ductal adenocarcinoma(PDAC)is a deadly malignancy,due in large part to its resistance to conventional therapies,including radiotherapy(RT).Despite RT exerting a modest antitumor response,it has also been shown to promote an immunosuppressive tumor microenvironment.Previous studies demonstrated that focal adhesion kinase inhibitors(FAKi)in clinical development inhibit the infiltration of suppressive myeloid cells and T regulatory(T regs)cells,and subsequently enhance effector T cell infiltration.FAK inhibitors in clinical development have not been investigated in combination with RT in preclinical murine models or clinical studies.Thus,we investigated the impact of FAK inhibition on RT,its potential as an RT sensitizer and immunomodulator in a murine model of PDAC.Methods:We used a syngeneic orthotopic murine model to study the effect of FAKi on hypofractionated RT.Results:In this study we showed that IN10018,a small molecular FAKi,enhanced antitumor response to RT.Antitumor activity of the combination of FAKi and RT is T cell dependent.FAKi in combination with RT enhanced CD8+T cell infiltration significantly in comparison to the radiation or FAKi treatment alone(P<0.05).FAKi in combination with radiation inhibited the infiltration of granulocytes but enhanced the infiltration of macrophages and T regs in comparison with the radiation or FAKi treatment alone(P<0.01).Conclusions:These results support the clinical development of FAKi as a radiosensitizer for PDAC and combining FAKi with RT to prime the tumor microenvironment of PDAC for immunotherapy. 相似文献
82.
We have previously shown ethanol-induced defects in receptor-mediated endocytosis of asialoorosomucoid (ASOR), epidermal growth factor (EGF), and insulin in isolated rat hepatocytes. The present study was undertaken to compare the binding of these three ligands in both Zone 1 (periportal [PP] region) and Zone 3 (perivenule [PV] region) of rat liver. Cells from the PV region of ethanol-fed animals bound significantly less EGF (40% decrease) than did cells from the same area in control rats. EGF binding was decreased to a lesser extent (15–25%) in PP cells from ethanol-fed animals compared to controls. When binding of ASOR was examined, ethanol feeding significantly impaired binding in both PP cells (30–35% decrease) and PV cells (50–55% decrease), again showing a greater ethanol-induced impairment in the PV region. Insulin binding in ethanol animals was decreased by 20–25% in both regions compared to controls. In addition, we found that ASOR receptor recycling was impaired to a greater extent in the PV than in the PP region of liver after ethanol feeding, indicating selective impairment of receptor function in the centrilobular region of the liver. 相似文献
83.
In a previous investigation (Irion et al., 1987), a significant age-related decline in skeletal muscle blood flow during intermittent tetanic contractions was observed in male Fischer 344 rats. This decline in the hyperemic response to muscle contraction was accompanied by an increased fatigability of skeletal muscle of senescent male rats. In the present investigation, anesthetized female adult and senescent Fischer 344 rats were instrumented for stimulation of the plantar flexor muscles in situ, and blood flow measurement by the tracer microsphere technique. After determination of optimum length and maximum tetanic force, muscles were stimulated to contract at the rate of 120 tetani/min. No significant differences could be observed between adult and senescent females in skeletal muscle fatigability or blood flow. The only significant differences observed between senescent and younger females were a decrease in splenic blood flow and an increase in body weight. In contrast to male rats of the same age, no impairment of skeletal muscle blood flow or change in fatigability could be detected in senescent female rats. 相似文献
84.
Juliane Winkler Pengyuan Liu Kiet Phong Johanna H. Hinrichs Nassim Ataii Katherine Williams Elin Hadler-Olsen Susan Samson Zev J. Gartner Susan Fisher Zena Werb 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(11)
Environmental chemicals such as bisphenol A (BPA) are thought to contribute to carcinogenesis through their endocrine-disrupting properties. Due to accumulating evidence about negative human health effects, BPA is being phased out, but in parallel, exposures to replacement chemicals such as bisphenol S (BPS) and bisphenol F (BPF) are increasing. Little is known about their biologic effects, but because of their high degree of chemical relatedness, they may have overlapping as well as distinct actions as compared with BPA. We investigated this theory using a nonmalignant, human breast tissue-derived organoid system and two end points: morphologic and proteomic alterations. At low-nanomolar doses, replacement chemicals—particularly BPS—disrupted normal mammary organoid architecture and led to an increased branching phenotype. Treatment with the various bisphenols (vs. 17-β-estradiol or a vehicle control) produced distinct proteomic changes. For example, BPS up-regulated Cdc42-interacting protein 4, which supports the formation of invadopodia and a mesenchymal phenotype. In summary, this study used a highly physiologically relevant organoid system to provide evidence that replacement bisphenols have protumorigenic effects on the mammary gland at morphologic and proteomic levels, highlighting the importance of studies to evaluate the potential harmful effects of structurally related environmental chemicals.Bisphenols, of which the most prevalent is bisphenol A (BPA), are environmental chemicals that are used as plasticizers in a variety of goods, including plastic bottles, children''s toys, eyeglass lenses, food containers, and some types of thermal paper (e.g., cash register receipts). They leach from these products, contaminating humans (and animals) either directly or indirectly via other environmental media, such as household dust. Thus, in most adults, BPA is detected in serum, tissues, and urine (1, 2). Children (ages 6 to 11) have the highest concentrations of urinary BPA (3, 4). This chemical has structural similarities to estrogen (17-β-estradiol [E2]) and as a result, weakly mimics its activity (5). Hormones and growth factors play an important role in controlling prenatal mammary gland development and later on, the morphologic and functional alterations that occur during puberty, pregnancy, and eventually, menopause. Due to this plasticity, the mammary gland is particularly susceptible to the actions of endocrine-disrupting chemicals (EDCs), such as BPA (6–8). In vivo and in vitro studies have consistently shown that exposures to BPA at crucial developmental stages impair mammary gland development and increase neoplastic transformation (9–12). Treating rats with BPA results in mammary epithelial hyperplasia and enhances proliferation (13), common features of precancerous lesions. Additionally, BPA induces cell cycle progression and increases proliferation of human breast cancer cells in vitro via the up-regulated expression of estrogen-dependent genes (14).Based on these and other data, BPA has been removed from many commercial products. Most commonly, this chemical of concern is replaced by bisphenol S (BPS) and bisphenol F (BPF) compounds that share close structural similarities with BPA. However, little is known about their endocrine effects and more broadly, their biological activities. Marketing a product as “BPA free” suggests to the consumer that a product is safer, but research shows that replacement bisphenols have adverse effects similar to, or even greater than, BPA. For example, studies in zebrafish, rodents, and human cell culture models show that BPS and BPF have endocrine-disrupting activities. In zebrafish, despite species-specific differences in estrogen receptor (ER) affinity and specificity, BPF and BPS have estrogenic activities similar to BPA (15–17). In rats, exposure to BPF induces uterine growth, which suggests estrogenic effects (18). BPA, BPF, and BPS promote estrogen-dependent cell cycle progression, proliferation, and migration of human MCF-7 breast cancer cells along with epigenetic changes (19, 20). BPS exposure of pregnant and lactating mice limits milk production, suggesting alterations in mammary gland composition (21). In addition to estrogen signaling, BPF affects other endocrine pathways; in rats, oral administration of this compound alters thyroid hormone levels (22).Current research on bisphenol actions is mainly focused on endocrine effects. It is less well understood whether these chemicals have additional protumorigenic effects independent of their endocrine-disrupting activity. Moreover, tumor development is a multistep process involving heterogeneous cell types and numerous factors, including the potential roles of a variety of environmental chemicals (23, 24). Recapitulating this complexity in an experimental setup is challenging. In this context, tissue organoids are valuable models for understanding the early steps of carcinogenesis. They can be derived from nonmalignant primary tissues ex vivo. When grown for short periods of time in vitro, they maintain many of the genetic and epigenetic features of their normal cognates. Also, organoids have the added advantage of consisting of multiple cell types that are representative of the complexity of the tissue from which they are derived (25, 26).In this study, we exploited the strengths of the human mammary gland organoid culture system to understand the impact of the BPA replacements, BPF and BPS. Organoids established from nonmalignant human mammary gland tissues were exposed to one of the bisphenols, E2, or the vehicle control. The results showed that BPA replacements, in particular BPS, disrupted organoid architecture, enhanced branching, and caused compound-specific proteomic alterations—effects that were mostly E2 independent. Together, these observations suggested that the mammary gland effects of BPA substitutes should be equally or more concerning than those of the compound they are replacing. 相似文献
85.
Michael Nothnagel Reinhard Szibor Oliver Vollrath Christa Augustin Jeanett Edelmann Maria Geppert Cíntia Alves Leonor Gusmão Marielle Vennemann Yiping Hou Uta-Dorothee Immel Serena Inturri Haibo Luo Sabine Lutz-Bonengel Carlo Robino Lutz Roewer Burkhard Rolf Juliane Sanft Kyoung-Jin Shin Jeong Eun Sim Sandra Hering 《Forensic science international. Genetics》2012,6(6):778-784
A large number of short tandem repeat (STR) markers spanning the entire human X chromosome have been described and established for use in forensic genetic testing. Due to their particular mode of inheritance, X-STRs often allow easy and informative haplotyping in kinship analyses. Moreover, some X-STRs are known to be tightly linked so that, in combination, they constitute even more complex genetic markers than each STR taken individually. As a consequence, X-STRs have proven particularly powerful in solving complex cases of disputed blood relatedness. However, valid quantification of the evidence provided by X-STR genotypes in the form of likelihood ratios requires that the recombination rates between markers are exactly known. In a collaborative family study, we used X-STR genotype data from 401 two- and three-generation families to derive valid estimates of the recombination rates between 12 forensic markers widely used in forensic testing, namely DXS10148, DXS10135, DXS8378 (together constituting linkage group I), DXS7132, DXS10079, DXS10074 (linkage group II), DXS10103, HPRTB, DXS10101 (linkage group III), DXS10146, DXS10134 and DXS7423 (linkage group IV). Our study is the first to simultaneously allow for mutation and recombination in the underlying likelihood calculations, thereby obviating the bias-prone practice of excluding ambiguous transmission events from further consideration. The statistical analysis confirms that linkage groups I and II are transmitted independently from one another whereas linkage groups II, III and IV are characterised by inter-group recombination fractions that are notably smaller than 50%. Evidence was also found for recombination within all four linkage groups, with recombination fraction estimates ranging as high as 2% in the case of DXS10146 and DXS10134. 相似文献
86.
Juliane Callegaro Borsa Bruno Figueiredo Damásio Denise Ruschel Bandeira Paola Gremigni 《Child psychiatry and human development》2013,44(6):766-776
This study examines measurement invariance, reliability and scores differences of the Peer Aggressive and Reactive Behaviors Questionnaire (PARB-Q) across Italian and Brazilian children, gender and age. Participants were 587 Italian and 727 Brazilian children, aged 7–13 years from 12 elementary schools. The PARB-Q is a brief self-report instrument composed by two scales that assess aggressive behavior and reactions to peer aggression. Multigroup confirmatory factor analyses indicated full measurement invariance of the PARB-Q across groups based on country, gender and age, providing support for the unidimensionality of the first scale (direct peer aggression, PA) and a 3-factor model of the second scale (reactive aggression, RA; seeking teacher support, STS; internalizing reaction, IR). Reliability indices were good for all factors. Italian children reported a higher frequency of PA and a lower frequency of IR than the Brazilian children. Boys scored higher than girls on PA and RA, while girls scored higher than boys on STS and IR. Younger children reported a lower frequency of PA and a higher frequency of STS than older children. Results provide support for structure validity and reliability of the PARB-Q in two countries and information on differences related to gender, age and culture in peer relationships in elementary school. 相似文献
87.
Stefan Vetter Astrid Rossegger Thomas Elbert Juliane Gerth Frank Urbaniok Arja Laubacher Wulf Rossler Jérôme Endrass 《BMC public health》2011,11(1):18
Background
In the aftermath of the Tsunami disaster in 2004, an online psychological self-assessment (ONSET) was developed and made available by the University of Zurich in order to provide an online screening instrument for Tsunami victims to test if they were traumatized and in need of mental health care. The objective of the study was to report the lessons learnt that were made using an Internet-based, self-screening instrument after a large-scale disaster and to discuss its outreach and usefulness. 相似文献88.
Luc Lorgis Sebastien Amoureux Emmanuel De Maistre Pierre Sicard Yannick Bejot Marianne Zeller Catherine Vergely Annabelle Sequeira‐Le Grand Anne‐Cécile Lagrost Juliane Berchoud Yves Cottin Luc Rochette 《Fundamental & clinical pharmacology》2010,24(4):525-530
Little is known about the role of neurotrophins (NT) under adult vascular homeostasis in normal and pathological conditions. The NT family, including nerve growth factor and brain‐derived neurotrophic factor (BDNF) are expressed in atherosclerotic vessels. Previous studies demonstrated that plasma BDNF levels were increased in the coronary circulation in patients with unstable angina. However, the role of BDNF during the onset and evolution of unstable angina remains to be elucidated. The objective of this study was to evaluate the relationship between BDNF, functional parameters and biological markers associated with inflammatory processes and platelet activation. BDNF serum levels were assessed in patients with acute myocardial infarction (MI) (n = 20) or stable angina pectoris (SAP) (n = 20) who underwent coronary angiography. Serum levels of IL‐6, MCP1, sVCAM, soluble CD‐40‐ligand (sCD40L) and soluble P‐selectin (sP‐selectin) were measured simultaneously by flux cytometry. Median BDNF levels were higher in the MI than in the SAP group (1730 vs. 877 pg/mL, respectively; P = 0.025). In MI patients, we observed a significant correlation between BDNF and sP‐selectin (r = 0.58, P = 0.023), although we found a non‐significant trend between BDNF and sCD40L (r = +0.35, P = 0.144). By contrast, no such correlation was observed in SAP patients (r = ?0.22, P = 0.425). No difference was observed between the two groups regarding baseline demographics, risk factors, biological data and angiographic findings. The study suggests that BDNF serum levels in MI patients could be related to platelet activation and the inflammatory response. Further studies are needed to investigate the role of NT in the setting of acute MI. 相似文献
89.
90.
Imitation in speech refers to the unintentional transfer of phonologically irrelevant acoustic-phonetic information of auditory input into speech motor output. Evidence for such imitation effects has been explained within the framework of episodic theories. However, it is largely unclear, which neural structures mediate speech imitation and how imitation is related with verbal repetition. Two experiments were conducted, a standard repetition task, and a transformation task requiring phonetic manipulation of the presented auditory nonword stimuli. Nonword materials varied sub-phonemically in word stress (pitch elevation magnitude; PEM) and in a parameter related to speaking style, i.e., the explicitness of final schwa-syllables (SSE). We examined speech imitation in 10 healthy participants, 10 patients with phonological impairments after left hemisphere lesions, and 11 patients with right hemisphere lesions. In repetition, significant imitation of SSE and PEM was observed in all groups of participants. In transformation, imitation occurred in healthy participants and in the patients with right hemisphere lesions, whereas no imitation was observed in the patient group with left hemisphere lesions. Voxel-based lesion-symptom mapping revealed that different areas within the left temporal plane influenced the degree of imitation of phonetic and prosodic detail in repetition. 相似文献