Murine Kidney Transplant Technique

The first mouse kidney transplant technique was published in 19731 by the Russell laboratory. Although it took some years for other labs to become ...

University of Colorado School of Medicine, University of Colorado-Denver

Traumatic injuries are a major cause of morbidity and mortality in children. The purpose of the present study was to determine the incidence of nonaccidental trauma (NAT) and to compare the outcomes of accidental trauma (AT) patients with NAT patients at a large pediatric trauma center.

Nonaccidental trauma is a major cause of morbidity and mortality among patients at a regional level 1 pediatric trauma center.

Non-islet cell tumor induced hypoglycemia (NICTH) is a very rare phenomenon, but even more so in gastrointestinal stromal tumors. It tends to present in large or metastatic tumors, and can appear at any time in the progression of the disease. We present herein a case of NICTH in a GIST tumor and report an exon 9 mutation associated to it.

Severe paraneoplastic hypoglycemia in a patient with a gastrointestinal stromal tumor with an exon 9 mutation: a case report.

When cecal intubation is a "must".

Posthemorrhagic shock mesenteric lymph (PSML) has been shown to activate pulmonary endothelial cells and cause lung injury. Although multiple mediators may be involved, most of these effects are mediated by nuclear factor-kappa B (NF-kappaB) activation. Degradation of the inhibitor of kappa B (IkappaB) is a key regulatory step in the activation of NF-kappaB. We therefore hypothesized that PSML would cause IkappaB degradation with subsequent NF-kappaB phosphorylation and nuclear translocation.

Postshock mesenteric lymph induces endothelial NF-kappaB activation.

Resuscitation with hypertonic saline (HTS) attenuates acute lung injury (ALI) and modulates postinjury hyperinflammation. TNF-alpha-stimulated pulmonary epithelium is a major contributor to hemorrhage-induced ALI. We hypothesized that HTS would inhibit TNF-alpha-induced nuclear factor (NF)-kappaB proinflammatory signaling in pulmonary epithelial cells. Therefore, we pretreated human pulmonary epithelial cells (A549) with hypertonic medium (180 mM NaCl) for 30 min, followed by TNF-alpha stimulation (10 ng/mL). Key regulatory steps and protein concentrations in this pathway were assessed for significant alterations. Hypertonic saline significantly reduced TNF-alpha-induced intercellular adhesion molecule 1 levels and NF-kappaB nuclear localization. The mechanism is attenuated phosphorylation and delayed degradation of IkappaB alpha. Hypertonic saline did not alter TNF-alpha-induced p38 mitogen-activated protein kinase phosphorylation or constitutive vascular endothelial growth factor expression, suggesting that the observed inhibition is not a generalized suppression of protein phosphorylation or cellular function. These results show that HTS inhibits TNF-alpha-induced NF-kappaB activation in the pulmonary epithelium and, further, our understanding of its beneficial effects in hemorrhage-induced ALI.

Hypertonic saline attenuates TNF-alpha-induced NF-kappaB activation in pulmonary epithelial cells.

Allogeneic blood transfusion has an immunomodulatory capacity on its recipients through accumulation of immunologically active substances with blood storage, and prestorage leukoreduction reduces many of these mediators. We investigated lipopolysaccharide (LPS)-induced cytokine response of peripheral blood mononuclear cells (PBMCs) exposed to packed red blood cell (PRBC) supernatants from leukoreduced (LR) or non-leukoreduced (NLR) units with variable duration of storage. PRBC units were collected with or without leukoreduction on Day 0 before routine storage. The plasma fraction (supernatant) was isolated from LR and NLR units after 1 day (D1) or 42 days (D42) of storage and exposed to PBMCs versus control media for 24 h, then with LPS for an additional 24 h. Cell supernatants were analyzed for IL-1beta, IL-6, IL-8, IL-10, and TNF-alpha by cytokine bead array. IL-1beta, TNF-alpha, and IL-6 were significantly elevated in PRBC groups versus control. D42 NLR PRBC supernatant significantly increased secretion of IL-1beta and IL-6 compared to D1 NLR PRBC supernatant. LR significantly attenuated the cytokine response of IL-1beta. Thus, PRBC supernatant potentiates proinflammatory LPS-induced cytokine secretion from PBMCs. This response is accentuated with storage duration and partially attenuated with leukoreduction. These findings may partially explain the immune activation seen clinically after blood transfusion.

Red blood cell supernatant potentiates LPS-induced proinflammatory cytokine response from peripheral blood mononuclear cells.

Postinjury multiple organ failure (MOF) remains the leading cause of morbidity and late mortality after severe trauma. Our previous work consistently identified an association between thrombocytopenia and progression to MOF. In addition, recent studies suggest that platelets play a critical role in postinjury hyperinflammation. Therefore, we hypothesized that postinjury thrombocytopenia is a marker for progression to MOF.

Refractory postinjury thrombocytopenia is associated with multiple organ failure and adverse outcomes.

Firm neutrophil (PMN)-endothelial (EC) adhesion is crucial to the PMN-mediated hyperinflammation observed in acute lung injury. Hypertonic saline (HTS) used for resuscitation of hemorrhagic shock has been associated with a decreased incidence of PMN-mediated lung injury/acute respiratory distress syndrome. We hypothesize that physiologically accessible hypertonic incubation (170 vs. 140 mM, osmolarity ranging from 360 to 300 mOsm/L) inhibits proinflammatory activation of human pulmonary microvascular endothelial cells (HMVECs). Proinflammatory activation of HMVECs was investigated in response to tumor necrosis factor-α (TNF-α), including interleukin 8 (IL-8) release, intercellular adhesion molecule 1 (ICAM-1) surface expression, PMN adhesion, and signaling mechanisms under both isotonic (control) and hypertonic conditions. Hyperosmolarity alone had no effect on either basal IL-8 release or ICAM-1 surface expression but did lead to concentration-dependent decreases in TNF-α-induced IL-8 release, ICAM-1 surface expression, and PMN-HMVEC adhesion. Conversely, HTS activated p38 mitogen-activated protein kinase (MAPK) and enhanced TNF-α activation of p38 MAPK. Despite this basal activation, hyperosmolar incubation attenuated TNF-α-stimulated IL-8 release and ICAM-1 surface expression and subsequent PMN adherence, while p38 MAPK inhibition did not further influence the effects of hyperosmolar conditions on ICAM-1 surface expression. In addition, TNF-α induced nuclear factor-κB DNA binding, but HTS conditions attenuated this by 31% (P < 0.01). In conclusion, HTS reduces PMN-HMVEC adhesion and TNF-α-induced proinflammatory activation of primary HMVECs via attenuation of nuclear factor-κB signaling.

Hyperosmolarity attenuates TNF-α-mediated proinflammatory activation of human pulmonary microvascular endothelial cells.

Hypertonic saline (HTS) has been used intravenously to reduce organ dysfunction following injury and as an inhaled therapy for cystic fibrosis lung disease. The role and mechanism of HTS inhibition was explored in the TNFα and IL-1β stimulation of pulmonary epithelial cells. Hyperosmolar (HOsm) media (400 mOsm) inhibited the production of select cytokines stimulated by TNFα and IL-1β at the level of mRNA translation, synthesis and release. In TNFα stimulated A549 cells, HOsm media inhibited I-κBα phosphorylation, NF-κB translocation into the nucleus and NF-κB nuclear binding. In IL-1β stimulated cells HOsm inhibited I-κBα phosphorylation without affecting NF-κB translocation or nuclear binding. Incubation in HOsm conditions inhibited both TNFα and IL-1β stimulated nuclear localization of interferon response factor 1 (IRF-1). Additional transcription factors such as AP-1, Erk-1/2, JNK and STAT-1 were unaffected by HOsm. HTS and sorbitol supplemented media produced comparable outcomes in all experiments, indicating that the effects of HTS were mediated by osmolarity, not by sodium. While not affecting MAPK modules discernibly in A549 cells, both HOsm conditions inhibit IRF-1 against TNFα or IL-1β, but inhibit p65 NF-kB translocation only against TNFα but not IL-1β. Thus, anti-inflammatory mechanisms of HTS/HOsm appear to disrupt cytokine signals at distinct intracellular steps.

Hyperosmolarity invokes distinct anti-inflammatory mechanisms in pulmonary epithelial cells: evidence from signaling and transcription layers.

One of the most challenging research microsurgical techniques is the mouse kidney transplant however, very few laboratories have made use of this important model due to its difficulty. One of the main obstacles to utilizing this procedure is the high incidence of post-operative arterial thrombosis. We believe this is caused by the path in which blood is required to flow from the recipient abdominal aorta, via the donor recipient aorta and on into the renal artery creating a tortuous route and areas of turbulence, which are prone to thrombus formation and failure of the graft.

Revised Arterial Anastomosis for Improving Murine Kidney Transplant Outcomes.

The long-term impact of allosensitization between ABO compatible donor/recipient pairs in liver transplantation is unclear. Accumulating clinical evidence suggests that donor-specific antibody formation may lead to antibody-mediated rejection and is causally linked to pathologic injury, graft loss, and death. Although this immune-mediated graft dysfunction is increasingly being associated with poor outcomes, the specific pathologic sequelae are not defined. Herein, we examine the relationship between allosensitization, antibody-mediated rejection, and subsequent graft pathology.

Article	Year
Nonaccidental trauma is a major cause of morbidity and mortality among patients at a regional level 1 pediatric trauma center. Journal of pediatric surgery\| PubMed ID: 17161194	2006
Severe paraneoplastic hypoglycemia in a patient with a gastrointestinal stromal tumor with an exon 9 mutation: a case report. BMC cancer\| PubMed ID: 17229322	2007
When cecal intubation is a "must". Gastrointestinal endoscopy\| PubMed ID: 17466204	2007
Postshock mesenteric lymph induces endothelial NF-kappaB activation. The Journal of surgical research\| PubMed ID: 17950083	2007
Hypertonic saline attenuates TNF-alpha-induced NF-kappaB activation in pulmonary epithelial cells. Shock (Augusta, Ga.)\| PubMed ID: 18948845	2009
Red blood cell supernatant potentiates LPS-induced proinflammatory cytokine response from peripheral blood mononuclear cells. Journal of interferon & cytokine research : the official journal of the International Society for Interferon and Cytokine Research\| PubMed ID: 19441884	2009
Refractory postinjury thrombocytopenia is associated with multiple organ failure and adverse outcomes. The Journal of trauma\| PubMed ID: 21307741	2011
Hyperosmolarity attenuates TNF-α-mediated proinflammatory activation of human pulmonary microvascular endothelial cells. Shock (Augusta, Ga.)\| PubMed ID: 23364439	2013
Hyperosmolarity invokes distinct anti-inflammatory mechanisms in pulmonary epithelial cells: evidence from signaling and transcription layers. PloS one\| PubMed ID: 25479425	2014
Revised Arterial Anastomosis for Improving Murine Kidney Transplant Outcomes. Journal of investigative surgery : the official journal of the Academy of Surgical Research\| PubMed ID: 26087146	2015
Pathologic sequelae of allosensitization in liver transplantation. The Journal of surgical research\| PubMed ID: 26253457	2015

Trevor L. Nydam

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