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71.
Human mesenchymal stromal cells modulate T‐cell responses through TNF‐α‐mediated activation of NF‐κB 下载免费PDF全文
Akaitz Dorronsoro Izaskun Ferrin Juan Manuel Salcedo Emma Jakobsson Jon Fernández‐Rueda Valérie Lang Pilar Sepulveda Karoline Fechter Dan Pennington César Trigueros 《European journal of immunology》2014,44(2):480-488
Although mesenchymal stromal cells (MSCs) possess the capacity to modulate immune responses, little is known about the mechanisms that underpin these processes. In this study, we show that immunosupression is mediated by activation of nuclear factor kappa B (NF‐κB) in human MSCs. This pathway is activated by TNF‐α that is generated following TCR stimulation of T cells. Inhibition of NF‐κB through silencing of IκB kinase β or the TNF‐α receptor abolishes the immunosuppressive capacity of MSCs. Our data also indicate that MSC‐associated NF‐κB activation primarily leads to inhibition of T‐cell proliferation with little effect on expression of the activation markers CD69 and CD25. Thus, our data support the hypothesis that the TNF‐α/NF‐κB signalling pathway is required for the initial priming of immunosuppressive function in human MSCs. Interestingly, drugs that interfere with NF‐κB activation significantly antagonise the immunoregulatory effect of MSCs, which could have important implications for immunosuppression regimens in the clinic. 相似文献
72.
73.
KA Pennington JL Harper AN Sigafoos LM Beffa SM Carleton CL Phillips LC Schulz 《Endocrinology》2012,153(9):4556-4567
Metabolic disease is a significant global health and economic problem. In a phenomenon referred to as fetal programming, offspring of underweight or overweight mothers have an increased incidence of adulthood obesity and metabolic disease. Undernourished individuals have decreased levels of leptin, a regulator of energy balance, whereas obese people develop hyperleptinemia and leptin resistance. We hypothesize that alterations in circulating leptin during pregnancy contribute to programming events caused by maternal nutritional status. To test this hypothesis, pregnant mice were randomly placed in one of three treatment groups: ad libitum feed plus saline injection (control, n = 5), 50% food restriction plus saline injection (restricted, n = 4), or 50% food restriction plus 1 mg/kg·d leptin injection (restricted, leptin treated, n = 4). Mice were treated from 1.5 to 11.5 d after conception and then returned to ad libitum feeding until weaning. At 19 wk after weaning, offspring were placed on a 45% fat diet and then followed up until 26 wk after weaning, at which time they were killed, and samples were collected for further analysis. Our results demonstrate that males are more negatively impacted by high-fat diet than females, regardless of maternal treatment. We provide evidence that differential response to leptin may mediate the sexual dimorphism observed in fetal programming in which male offspring are more affected by maternal undernutrition and female offspring by maternal overnutrition. We show that female offspring born to food-restricted, leptin-supplemented mothers are obese and insulin resistant. This may mimic fetal programming events seen in offspring of overweight women. 相似文献
74.
Pennington J Parker S 《Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)》2012,33(4):268-70, 272, 274-6
Removable and fixed implant-retained prostheses can greatly enhance patients' quality of life, improving their speech, appearance, and ability to eat and otherwise function normally. Yet patients may resist this type of treatment due to barriers, including cost, fear, and lengthy treatment times. It is, therefore, important that clinicians engage in discovering and understanding their patients' concerns and expectations in addition to making a thorough and complete diagnosis of their dental conditions. In the case presented, emphasis was placed on patient-clinician communication to correctly facilitate the desired clinical result. The final restoration consisted of a maxillary removable, implant-assisted denture and a mandibular screw-retained, fixed, implant-supported prosthesis. 相似文献
75.
非酒精性脂肪性肝炎(non—alcoholicsteatohepatitis,NASH)现已成为肝移植愈来愈重要的基础肝病。鉴于晚期NASH患者常并存多种影响肝移植转归的临床问题,而至今尚无针对NASH患者进行肝移植的评估和治疗指南,为此英国移植学会(British Transplant Society,BTS)邀请相关专家制定了指南,以指导肝移植前后NASH患者的处理。 相似文献
76.
Florian ME Wagenlehner Christoph Lichtenstern Caroline Rolfes Konstantin Mayer Florian Uhle Wolfgang Weidner Markus A Weigand 《International journal of urology》2013,20(10):963-970
Urosepsis is defined as sepsis caused by a urogenital tract infection. Urosepsis in adults comprises approximately 25% of all sepsis cases, and is in most cases due to complicated urinary tract infections. The urinary tract is the infection site of severe sepsis or septic shock in approximately 10–30% of cases. Severe sepsis and septic shock is a critical situation, with a reported mortality rate nowadays still ranging from 30% to 40%. Urosepsis is mainly a result of obstructed uropathy of the upper urinary tract, with ureterolithiasis being the most common cause. The complex pathogenesis of sepsis is initiated when pathogen or damage‐associated molecular patterns recognized by pattern recognition receptors of the host innate immune system generate pro‐inflammatory cytokines. A transition from the innate to the adaptive immune system follows until a TH2 anti‐inflammatory response takes over, leading to immunosuppression. Treatment of urosepsis comprises four major aspects: (i) early diagnosis; (ii) early goal‐directed therapy including optimal pharmacodynamic exposure to antimicrobials both in the plasma and in the urinary tract; (iii) identification and control of the complicating factor in the urinary tract; and (iv) specific sepsis therapy. Early adequate tissue oxygenation, adequate initial antibiotic therapy, and rapid identification and control of the septic focus in the urinary tract are critical steps in the successful management of a patient with urosepsis, which includes early imaging, and an optimal interdisciplinary approach encompassing emergency unit, urological and intensive‐care medicine specialists. 相似文献
77.
M. Redley E. Prince N. Bateman M. Pennington N. Wood T. Croudace H. Ring 《Journal of intellectual disability research : JIDR》2013,57(6):531-538
Background Patients with intellectual disabilities (ID) receive health care by proxy. It is family members and/or paid support staff who must recognise health problems, communicate with clinicians, and report the benefits, if any, of a particular treatment. At the same time international and national statutes protect and promote the right of people with disabilities to access the highest attainable standards of health on the basis of free and informed consent. Methods To consider the role of parent‐proxies in the management of epilepsy in adult children with ID who are at risk of lacking capacity to make decisions about their health care we interviewed 21 mothers. Findings These mothers are not pursuing changes in treatment that might improve their son or daughter's epilepsy, nor are they willing to countenance changes in treatment. Clinicians concerned to build and sustain therapeutic alliances with these mothers, our evidence suggests, may well avoid going against their wishes. Discussion Our research highlights the interactional contingencies of a hitherto neglected three‐way clinical relationship comprising parent‐proxy, an adult at risk of lacking decision‐making capacity, and a treating clinician. This is a relationship, our findings suggest, where little importance is attached to either patient consent, or involvement in treatment decisions. 相似文献
78.
C. A. Downs Esti Kramarsky-Winter John E. Fauth Roee Segal Omri Bronstein Rina Jeger Yona Lichtenfeld Cheryl M. Woodley Paul Pennington Ariel Kushmaro Yossi Loya 《Ecotoxicology (London, England)》2014,23(2):175-191
Benzophenone-2 (BP-2) is an additive to personal-care products and commercial solutions that protects against the damaging effects of ultraviolet light. BP-2 is an “emerging contaminant of concern” that is often released as a pollutant through municipal and boat/ship wastewater discharges and landfill leachates, as well as through residential septic fields and unmanaged cesspits. Although BP-2 may be a contaminant on coral reefs, its environmental toxicity to reefs is unknown. This poses a potential management issue, since BP-2 is a known endocrine disruptor as well as a weak genotoxicant. We examined the effects of BP-2 on the larval form (planula) of the coral, Stylophora pistillata, as well as its toxicity to in vitro coral cells. BP-2 is a photo-toxicant; adverse effects are exacerbated in the light versus in darkness. Whether in darkness or light, BP-2 induced coral planulae to transform from a motile planktonic state to a deformed, sessile condition. Planulae exhibited an increasing rate of coral bleaching in response to increasing concentrations of BP-2. BP-2 is a genotoxicant to corals, exhibiting a strong positive relationship between DNA-AP lesions and increasing BP-2 concentrations. BP-2 exposure in the light induced extensive necrosis in both the epidermis and gastrodermis. In contrast, BP-2 exposure in darkness induced autophagy and autophagic cell death. The LC50 of BP-2 in the light for an 8 and 24 h exposure was 120 and 165 parts per billion (ppb), respectively. The LC50s for BP-2 in darkness for the same time points were 144 and 548 ppb. Deformity EC20 levels (24 h) were 246 parts per trillion in the light and 9.6 ppb in darkness. 相似文献
79.
P J Loehrer L H Einhorn S D Williams S L Hui N C Estes K Pennington 《Cancer treatment reports》1985,69(12):1359-1363
Cisplatin plus 5-FU appears to have significant additive activity in various tumors, such as head and neck carcinoma and esophageal cancer. A partial explanation for this may be drug synergism, which has been noted in the L1210 leukemia model. Based on these data, a prospective trial of weekly bolus 5-FU (15 mg/kg) and cisplatin (60 mg/m2) given every 3 weeks was initiated at Indiana University. Forty-one patients, of whom 38 are fully evaluable for response, were treated with these two drugs. Ten partial and one complete response (complete + partial response rate = 29%) were observed in the 38 evaluable patients. Thirteen additional patients had stable disease for greater than or equal to 3 months. The median durations of remission and survival time were 6 and 10.3 months, respectively. Myelosuppression was unusually severe, with granulocyte counts less than 1000/mm3 in 65% of patients, including four patients with granulocyte count nadirs less than 100/mm3. Three patients developed granulocytopenic fever, with two drug-related deaths (sepsis, hyperosmolar coma). Nearly all patients had nausea and vomiting, but this was not a treatment-limiting toxic effect in any patient. Although this combination suggests a higher response rate than usually seen with bolus iv 5-FU in colon cancer, a trial comparing 5-FU alone or with cisplatin to determine whether true synergy exists is currently underway. 相似文献
80.
van Gils FC; van Teeffelen ME; Neelis KJ; Hendrikx J; Burger H; van Leen RW; Knol E; Wagemaker G; Wognum AW 《Blood》1995,86(2):592-597
To understand the hematopoietic and nonhematopoietic responses to interleukin-3 (IL-3), expression of cell-surface IL-3 receptors (IL-3R) was examined on bone marrow (BM) cells and peripheral blood (PB) cells of rhesus monkeys during the course of in vivo IL-3 treatment. Whereas IL-3R expression is low in untreated monkeys, IL-3 administration led to a gradual increase in both low- and high-affinity binding sites for IL-3. This increase reflected the total number of cells expressing IL- 3Rs, as detected by flow cytometry using biotinylated IL-3. Most of these IL-3R+ cells in both BM and PB could be characterized as basophilic granulocytes that contained high levels of histamine. In contrast to the effect on these differentiated cells, IL-3 administration did not significantly alter the low level IL-3R expression on immature, CD34+ cells. Further flow cytometric analysis using biotinylated growth factors showed that the IL-3R+ basophils also expressed receptors for granulocyte-macrophage colony-stimulating factor (GM-CSF), but not for IL-6 or Kit ligand. These findings indicated that the IL-3R+ cells included neither monocytes, which express GM-CSFRs and IL-6Rs abundantly, nor mast cells, which express c- kit. By combining flow cytometric and Scatchard data, it was calculated that the basophils contain as many as 1 to 2 x 10(3) high-affinity IL- 3Rs and 15 to 30 x 10(3) low-affinity sites. The finding that in vivo IL-3 treatment leads to the production of large numbers of cells that express high levels of IL-3R and are capable of producing histamine provides an explanation for the often severe allergic reactions that occur during prolonged IL-3 administration. It also indicates that IL- 3, in addition to its direct effects on hematopoietic cells, may also stimulate hematopoiesis through the release of secondary mediators such as histamine by IL-3-responsive mature cells. 相似文献