Necrotizing Soft Tissue Infection Secondary to Streptococcus constellatus, Actinomyces odontolyticus, and Gemella morbillorum in an Intravenous Drug User: A Case Report and Literature Review.

A 53-year-old male with active IV heroin use presented with left upper extremity pain, erythema, swelling, and purulent foul-smelling drainage. Rapid diagnosis of necrotizing soft tissue infection (NSTI) was made based on clinical and radiologic findings. He was taken to the operating room for wound washouts and surgical debridements. The early microbiologic diagnosis was made based on intraoperative cultures. Successful treatment of NSTI in the setting of rare pathogens was achieved. The wound was ultimately treated with wound vac therapy, followed by primary delayed closure of the upper extremity and skin grafting of the forearm. We present a case of NSTI secondary to Streptococcus constellatus, Actinomyces odontolyticus, and Gemella morbillorum in an intravenous (IV) drug user, successfully treated with early surgical intervention.

Cognitive Bias Impact on Management of Postoperative Complications, Medical Error, and Standard of Care.

BACKGROUND: Cognitive bias (CB) is increasingly recognized as an important source of medical error and up to 75% of errors in internal medicine are thought to be cognitive in origin (O'Sullivan ED, Schofield SJ. Cognitive bias in clinical medicine. J R Coll Physicans Edinb. 2018;48;225-232). However, primary data regarding the true incidence of bias is lacking. A prospective evaluation of CB in the management of surgical cases with complications has not been reported. This study reports the incidence and distribution of various types of CBs, and evaluates their impact on management errors and standard of care (SOC). METHODS: A prospectively collected series of 736 general surgical cases with complications from three university hospitals was analyzed. Surgical residents evaluated cases for 22 types of CBs (Croskerry P. The importance of cognitive errors in diagnosis and strategies to minimize them. Acad Med. 2003;78:775-780). Supervising quality officers validated all quality assessments. Data were assessed for the incidence of CBs, error assessments (diagnostic, technical, judgment, system, communication, therapeutic, and professionalism), and SOC. RESULTS: CB was attributed in 32.7% (241/736) of all cases with complications. The most common CBs identified, both singly and in groups, were anchoring, confirmation, omission, commission, overconfidence, premature closure, hindsight, diagnosis momentum, outcome, and ascertainment bias. The attribution of CB was correlated to a statistically significant increase in the incidence of management errors by the surgical team and lower SOC assessments. CONCLUSIONS: CBs are identified in the management of cases with complications and are associated with an increase in management errors and a degradation in SOC. Insight into the types of CBs and their association with the type and severity of management errors may prove useful in improving quality care.

Upper Gastrointestinal Bleeding.

Although its incidence is decreasing, upper gastrointestinal bleeding represents a significant cause of morbidity and mortality. We present the most common sources of upper gastrointestinal bleeding and treatments.

Extracellular microRNA 130b-3p inhibits eCIRP-induced inflammation.

Although microRNAs regulate mRNA expression intracellularly, they are often released into the circulation in inflammatory diseases. During sepsis, secreted extracellular cold-inducible RNA-binding protein (eCIRP) acts as a damage-associated molecular pattern (DAMP), inducing tissue damage by elevating inflammatory cytokines and chemokines. Here, we report that the circulating microRNA 130b-3p inhibits eCIRP-mediated sterile and cecal ligation and puncture (CLP)-induced non-sterile inflammation. We find that levels of miR-130b-3p are increased in the serum of septic mice and patients and that it strongly interacts with recombinant murine (rm) CIRP in vitro and with eCIRP in the serum of septic mice in vivo. Combining a miR-130b-3p mimic with rmCIRP significantly decreases TNF-α release by macrophages compared to only rmCIRP-treated cells. This combined treatment also dose-dependently decreases the affinity of rmCIRP with its receptor TLR4/MD2. Finally, injection of a miR-130b-3p mimic significantly reduces rmCIRP- or CLP-induced systemic inflammation and acute lung injury in mice. These data show that extracellular miR-130b-3p functions as a novel endogenous inhibitor of eCIRP and point to an innovative therapeutic approach to treat inflammatory diseases.

Cold-inducible RNA-binding protein-derived peptide C23 attenuates inflammation and tissue injury in a murine model of intestinal ischemia-reperfusion.

BACKGROUND: Cold-inducible RNA-binding protein is a novel damage-associated molecular pattern that causes inflammation. C23, a short peptide derived from cold-inducible RNA-binding protein, has been found to have efficacy in blocking cold-inducible RNA-binding protein's activity. We hypothesized that C23 reduces inflammation and tissue injury induced by intestinal ischemia-reperfusion. METHODS: Male C57BL/6 mice were subjected to 60 minutes of intestinal ischemia by clamping the superior mesenteric artery. Immediately after reperfusion, either normal saline (vehicle) or C23 peptide (8 mg/kg body weight) was injected intraperitoneally. Four hours after reperfusion, blood, intestinal, and lung tissues were collected for analysis of inflammatory and tissue injury parameters. RESULTS: Cold-inducible RNA-binding protein levels in the intestinal tissues were significantly increased following intestinal ischemia-reperfusion. Histologic examination of the intestine revealed a significant reduction in injury score in the C23 group by 48% as compared with the vehicles after intestinal ischemia-reperfusion. The serum levels of lactate dehydrogenase and aspartate aminotransferase were increased in animals that underwent vehicle-treated intestinal ischemia-reperfusion, whereas C23-treated animals exhibited significant reductions by 48% and 53%, respectively. The serum and intestinal tissue levels of tumor necrosis factor α were elevated in vehicle-treated intestinal ischemia-reperfusion mice but decreased by 72% and 69%, respectively, in C23-treated mice. Interleukin-6 mRNA levels in the lungs were reduced by 86% in the C23-treated group in comparison to the vehicle-treated group after intestinal ischemia-reperfusion. Expression of macrophage inflammatory protein 2 and level of myeloperoxidase activity in the lungs were dramatically increased after intestinal ischemia-reperfusion and significantly reduced by 91% and 25%, respectively, in the C23-treated group. CONCLUSION: C23 has potential to be developed into a possible therapy for reperfusion injury after mesenteric ischemia and reperfusion.

Activation of Invariant Natural Killer T Cells Redirects the Inflammatory Response in Neonatal Sepsis.

Sepsis is the third leading cause of death in the neonatal population, due to susceptibility to infection conferred by immaturity of both the innate and adaptive components of the immune system. Invariant natural killer T (iNKT) cells are specialized adaptive immune cells that possess important innate-like characteristics and have not yet been well-studied in septic neonates. We hypothesized that iNKT cells would play an important role in mediating the neonatal immune response to sepsis. To study this, we subjected 5- to 7-day-old neonatal C57BL/6 mice to sepsis by intraperitoneal (i.p.) cecal slurry (CS) injection. Thirty hours prior to or immediately following sepsis induction, pups received i.p. injection of the iNKT stimulator KRN7000 (KRN, 0.2 µg/g) or vehicle. Ten hours after CS injection, blood and tissues were collected for various analyses. Thirty-hour pretreatment with KRN resulted in better outcomes in inflammation, lung injury, and survival, while immediate treatment with KRN resulted in worse outcomes compared to vehicle treatment. We further analyzed the activation status of neonatal iNKT cells for 30 h after KRN administration, and showed a peak in frequency of CD69 expression on iNKT cells and serum IFN-γ levels at 5 and 10 h, respectively. We then used CD1d knockout neonatal mice to demonstrate that KRN acts through the major histocompatibility complex-like molecule CD1d to improve outcomes in neonatal sepsis. Finally, we identified that KRN pretreatment exerts its protective effect by increasing systemic levels of TGF-ß1. These findings support the importance of iNKT cells for prophylactic immunomodulation in neonates susceptible to sepsis.

Inhibition of necroptosis attenuates lung injury and improves survival in neonatal sepsis.

BACKGROUND: Neonatal sepsis represents a unique therapeutic challenge owing to an immature immune system. Necroptosis is a form of programmed cell death that has been identified as an important mechanism of inflammation-induced cell death. Receptor-interacting protein kinase 1 plays a key role in mediating this process. We hypothesized that pharmacologic blockade of receptor-interacting protein kinase 1 activity would be protective in neonatal sepsis. METHODS: Sepsis was induced in C57BL/6 mouse pups (5-7 days old) by intraperitoneal injection of adult cecal slurry. At 1 hour after cecal slurry injection, the receptor-interacting protein kinase 1 inhibitor necrostatin-1 (10 µg/g body weight) or vehicle (5% dimethyl sulfoxide in phosphate buffered saline) was administered via retro-orbital injection. At 20 hours after cecal slurry injection, blood and lung tissues were collected for various analyses. RESULTS: At 20 hours after sepsis induction, vehicle-treated pups showed a marked increase in serum levels of interleukin 6, interleukin 1-beta, and interleukin 18 compared to sham. With necrostatin-1 treatment, serum levels of interleukin 6, interleukin 1-beta, and interleukin 18 were decreased by 77%, 81%, and 63%, respectively, compared to vehicle. In the lungs, sepsis induction resulted in a 232-, 10-, and 2.8-fold increase in interleukin 6, interleukin 1-beta, and interleukin 18 mRNA levels compared to sham, while necrostatin-1 treatment decreased these levels to 40-, 4-, and 0.8-fold, respectively. Expressions of the neutrophil chemokines keratinocyte chemoattractant and macrophage-inflammatory-protein-2 were also increased in the lungs in sepsis, while necrostatin-1 treatment decreased these levels by 81% and 61%, respectively, compared to vehicle. In addition, necrostatin-1 treatment significantly improved the lung histologic injury score and decreased lung apoptosis in septic pups. Finally, treatment with necrostatin-1 increased the 7-day survival rate from 0% in the vehicle-treated septic pups to 29% (P = .11). CONCLUSION: Inhibition of receptor-interacting protein kinase 1 by necrostatin-1 decreases systemic and pulmonary inflammation, decreases lung injury, and increases survival in neonatal mice with sepsis. Targeting the necroptosis pathway might represent a new therapeutic strategy for neonatal sepsis.

The Protective Effect of A Short Peptide Derived From Cold-Inducible RNA-Binding Protein in Renal Ischemia-Reperfusion Injury.

Extracellular cold-inducible RNA-binding protein (CIRP) functions as damage-associated molecular pattern and has been demonstrated to be responsible in part for the damage occurring after renal ischemia-reperfusion (I/R). A short peptide derived from CIRP, named C23, binds to myeloid differentiation factor 2, a Toll-like receptor 4 coreceptor. We hypothesize that C23 reduces renal ischemia-reperfusion (RIR) injury by blocking CIRP. We observed that pretreatment with C23 significantly decreased the levels of recombinant mouse CIRP-induced tumor necrosis factor-α (TNF-α) in a dose-dependent fashion in cultured macrophages. C57BL/6 mice were subjected to bilateral renal pedicle clamps for 35 min to induce ischemia, followed by reperfusion for 24 h and harvest of blood and renal tissue. C23 peptide (8 mg/kg) or vehicle was injected intraperitoneally at the beginning of reperfusion. Plasma TNF-α, interleukin 1 beta (IL-1ß), and IL-6 levels were decreased in C23-treated RIR mice as compared with vehicle-treated mice by 74%, 85%, and 68%, respectively. Expressions of TNF-α and keratinocyte chemoattractant in the kidneys from C23-treated mice were decreased by 55% and 60%, respectively. Expression of kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin in the kidney of C23-treated mice were significantly reduced by 46% and 55%, respectively. Renal tissue histological assessments revealed significant reduction in damage score by 44% in C23-treated mice. Finally, a survival study revealed a significant survival advantage with a 70% survival rate in C23 group vs. 37% in vehicle group. Thus, C23 has potential as a novel therapy for the patients suffering from I/R-induced renal injury.

Deficiency of receptor-interacting protein kinase 3 (RIPK3) attenuates inflammation and organ injury in neonatal sepsis.

INTRODUCTION: Sepsis is the third leading cause of morbidity and mortality in neonates. Sepsis in neonates is characterized as the systemic inflammation owing to infection within the first 28days after birth. The molecular mechanism causing the exaggerated inflammation phenotype in neonates has not been completely elucidated. Receptor interacting protein kinase 3 (RIPK3) is a protein identified as a mediator in programmed necrosis or necroptosis. We hypothesize that RIPK3 could be responsible for the inflammatory response in neonates and that deficiency in the RIPK3 protein attenuates inflammation and organ injury in neonatal sepsis. METHODS: Male and female C57BL6 wild-type (WT) and RIPK3 knock-out (KO) newborn mice aged 5-7days (3-4g body weight) were injected intraperitoneally with 0.9mg/g cecal slurry (CS). At 10h after injection, the newborns were euthanized and blood, the lungs and gut tissues were collected. RESULTS: At 10h after CS injection, serum cytokines IL-6 and IL-1ß in the WT mice were increased by 511- and 43-fold whereas in KO mice, these levels were increased by 166-fold and 22-fold, respectively. Lung IL-1ß in the WT mice increased by 7-fold after CS injection whereas only a 4-fold increase was seen in the KO mice. In the lungs of CS injected KO mice, the injury score, MIP-2 mRNA, myeloperoxidase (MPO) activity and TUNEL staining were significantly reduced by 76%, 70%, 26% and 74%, respectively compared to the CS WT mice. Gut TUNEL staining was also reduced by 80%. CONCLUSION: The deficiency in RIPK3 attenuated serum and lung cytokines, lung injury and neutrophil infiltration and lung and gut apoptosis. These data suggest that RIPK3, in part, is responsible for the systemic inflammatory response in neonatal sepsis.

Cold-inducible RNA-binding protein activates splenic T cells during sepsis in a TLR4-dependent manner.

Cold-inducible RNA-binding protein (CIRP) is a novel inflammatory mediator that stimulates the release of proinflammatory cytokines from macrophages in sepsis. Given the immune dysregulation that characterizes sepsis, the effect of CIRP on other immune cells is an area of increasing interest that has not yet been studied. In the present study, we hypothesized that extracellular CIRP promotes activation of T lymphocytes in the spleen during sepsis. We observed that mice subjected to sepsis by cecal ligation and puncture showed significantly higher expression of the early activation markers CD69 and CD25 at 20 h on CD4+ splenic T cells, and significantly higher CD69 expression on CD8+ splenic T cells compared with sham-operated controls. Furthermore, at 20 h after receiving intravenous injection of recombinant murine CIRP (rmCIRP, 5 mg/kg body weight (BW)) or PBS (vehicle), those mice receiving rmCIRP showed significantly increased expression of CD69 and CD25 on both CD4+ and CD8+ splenic T cells. This effect, however, was not seen in TLR4-deficient mice after rmCIRP injection. In addition, treatment with CIRP predisposed CD4+ T cells to a Th1 hyperinflammatory response profile, and influenced CD8+ T cells toward a cytotoxic profile. Taken together, our findings indicate that CIRP is a proinflammatory mediator that plays an important role in T-cell dysregulation during sepsis in a TLR4-dependent manner.

SRT1720, a sirtuin 1 activator, attenuates organ injury and inflammation in sepsis.

BACKGROUND: Sepsis affects 800,000 patients in the United States annually with a mortality rate of up to 30%. Recent studies suggest that sepsis-associated metabolic derangements due to hypoxic tissue injury, impaired oxygen utilization, and mitochondrial dysfunction contribute to mortality. Sirtuin 1 (Sirt1) is a crucial modulator of energy metabolism during starvation states and has anti-inflammatory effects. Here, we hypothesized that SRT1720, a Sirt1 activator, could attenuate the severity of sepsis. MATERIALS AND METHODS: Male C57BL/6 mice (20-25 g) were subjected to cecal ligation and puncture (CLP) to induce sepsis. SRT1720 (5 or 20 mg/kg BW) or 10% dimethyl sulfoxide (vehicle) in 0.2-mL saline was injected intravenously at 5 h after CLP. Control animals were not subjected to any surgery. Blood and liver samples were harvested at 20 h after CLP for analysis. RESULTS: Administration of SRT1720 markedly reduced the serum levels of tissue injury markers (aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase) and renal injury markers (blood urea nitrogen and creatinine) in a dose-dependent manner after CLP. Furthermore, the levels of proinflammatory cytokines interleukin (IL)-1ß and IL-6 in the serum and liver were significantly inhibited by SRT1720 treatment after CLP. SRT1720 treatment resulted in a significantly decreased mRNA expression of inflammasome components (nucleotide oligomerization domain-like receptor protein 3, adapter apoptosis-associated speck-like protein containing caspase-recruitment domain, IL-1ß, and IL-18) in the liver, compared with the vehicle group. CONCLUSIONS: SRT1720 treatment attenuates multiorgan injury in septic mice. SRT1720 treatment also decreases the production of proinflammatory cytokines and reduces inflammasome activation. Thus, pharmacologic stimulation of Sirt1 may present a promising therapeutic strategy for sepsis.

Deficiency in cold-inducible RNA-binding protein attenuates acute respiratory distress syndrome induced by intestinal ischemia-reperfusion.

BACKGROUND: Intestinal ischemia-reperfusion can occur in shock and mesenteric occlusive diseases, causing significant morbidity and mortality. Aside from local injury, intestinal ischemia-reperfusion can result in remote organ damage, particularly in the lungs. Cold-inducible RNA-binding protein (CIRP) was identified as a novel inflammatory mediator. We hypothesized that a deficiency in CIRP would protect the lungs during intestinal ischemia-reperfusion injury. METHODS: Intestinal ischemia was induced in adult male C57BL/6 wild-type and CIRP knock-out (CIRP-/-) mice via clamping of the superior mesenteric artery for 60 minutes. Reperfusion was allowed for 4 hours or 20 hours, and blood, gut, and lung tissues were harvested for various analyses. RESULTS: After intestinal ischemia-reperfusion, the elevated levels of serum lactate dehydrogenase and inflammatory cytokine interleukin-6 were reduced by 68% and 98%, respectively, at 20 hours after ischemia-reperfusion in CIRP-/- mice compared with the wild-type mice. In the gut, mRNA levels of inflammatory cytokine interleukin-6 were reduced by 67% at 4 hours after ischemia-reperfusion in CIRP-/- mice. In the lungs, inflammatory cytokine interleukin-6 protein and myeloperoxidase activity were reduced by 78% and 26% at 20 hours and 4 hours after ischemia-reperfusion, respectively, in CIRP-/- mice. Finally, the elevated lung caspase-3 was significantly decreased by 55%, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells decreased by 91%, and lung injury score decreased by 37% in CIRP-/- mice at 20 hours after ischemia-reperfusion. CONCLUSION: Increased levels of proinflammatory cytokines, myeloperoxidase, and apoptosis are the hallmarks of acute respiratory distress syndrome. We noticed after intestinal ischemia-reperfusion the proinflammatory milieu in lungs was elevated significantly, while the CIRP-/- mice had significantly decreased levels of proinflammatory cytokine, myeloperoxidase, and apoptotic cells leading to decreased lung injury. These findings strongly established a causal link between CIRP and acute respiratory distress syndrome during intestinal ischemia-reperfusion injuries. Targeting CIRP may therefore be beneficial for treatment of intestinal ischemia-reperfusion-associated acute respiratory distress syndrome acute respiratory distress syndrome.

Milk fat globule-epidermal growth factor-factor VIII attenuates sepsis-induced acute kidney injury.

BACKGROUND: Acute kidney injury (AKI) is most commonly caused by sepsis in critically ill patients, and it is associated with high morbidity and mortality. The pathophysiology of sepsis-induced AKI is generally accepted to include direct inflammatory injury, endothelial cell dysfunction, and apoptosis. Milk fat globule-epidermal growth factor-factor VIII (MFG-E8) is a secretory glycoprotein with a known role in the enhancement of apoptotic cell clearance and regulation of inflammation. We hypothesize that administration of recombinant mouse MFG-E8 (rmMFG-E8) can protect mice from kidney injuries caused by sepsis. METHODS: Sepsis was induced in 8-wk-old male C57BL/6 mice by cecal ligation and puncture (CLP). rmMFG-E8 or phosphate-buffered saline (vehicle) was injected intravenously at a dosage of 20 µg/kg body weight at time of CLP (n = 5-8 mice per group). After 20 h, serum and renal tissue were harvested for various analyses. The renal injury markers blood urea nitrogen (BUN) and creatinine were determined by enzymatic and chemical reactions, respectively. The gene expression analysis was carried out by real-time quantitative polymerase chain reaction. RESULTS: At 20 h after CLP, serum levels of BUN and creatinine were both significantly increased in the vehicle group compared with the sham group, whereas the mice treated with rmMFG-E8 had a significant reduction in BUN and creatinine levels by 28% and 24.1%, respectively (BUN: 197.7 ± 23.6 versus 142.3 ± 20.7 mg/dL; creatinine: 0.83 ± 0.12 versus 0.63 ± 0.06 mg/dL; P < 0.05). Expressions of novel biomarkers of renal tissue injury neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 were also significantly downregulated by 58.2% and 95%, respectively, after treatment with rmMFG-E8. Proinflammatory cytokine interleukin-6 and tumor necrosis factor-α messenger RNA (mRNA) were significantly reduced by 50.8% and 50.3%, respectively, in rmMFG-E8-treated mice compared with vehicle-treated mice. The mRNA levels of the chemokines keratinocyte chemoattractant and macrophage inhibitory protein-2 were reduced by 85.1% and 78%, respectively, in mice treated with rmMFG-E8 compared with the vehicle mice. In addition, the expression of intercellular cell adhesion molecule-1 and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) mRNA was downregulated by 35.6% and 77.8%, respectively, in rmMFG-E8-treated mice compared with the vehicle animals (P < 0.05). CONCLUSIONS: Treatment with rmMFG-E8 reduces renal tissue injury induced by sepsis through inhibiting the production of proinflammatory cytokines and chemokine, as well as through the activation of endothelial cells. Thus, MFG-E8 may have a therapeutic potential for treating AKI induced by sepsis.

Plain radiography may underestimate the burden of body packer ingestion: A case report.

Body packing refers to the intracorporeal concealment of illicit drugs. Here we report the case of a 55-year-old body packer who presented with palpitations, visual hallucinations, and a sense of impending death. Abdominal radiography demonstrated five ovoid foreign bodies overlying the rectum. At subsequent gastrotomy and cecotomy, thirty-eight cocaine-containing packets were retrieved from the stomach and ascending colon as well as from the rectum. As the contraband market evolves new techniques to evade detection, evaluation of the burden of body packer ingestion has become increasingly challenging. As demonstrated in this case, plain radiography can grossly underestimate the burden of ingestion.

Treatment with milk fat globule epidermal growth factor-factor 8 (MFG-E8) reduces inflammation and lung injury in neonatal sepsis.

BACKGROUND: Sepsis remains one of the leading causes of infant death worldwide. It is characterized by uncontrolled inflammatory responses due to proven bacterial infection. Despite improvement in supportive care and the availability of effective antibiotics, no specific therapy targeting the dysregulated inflammatory response is available for neonatal sepsis. Milk fat globule epidermal growth factor-factor 8 (MFG-E8) is a secretory glycoprotein abundantly present in human milk. MFG-E8 suppresses the systemic inflammatory responses in adult murine injury models by improving the clearance of dying cells. We hypothesized that exogenous administration of recombinant mouse MFG-E8 could inhibit the exaggerated inflammatory response and lung injury in a murine model of neonatal sepsis. METHODS: Neonatal sepsis was induced in 5- to 7-day-old male and female C57BL6 mice using an intraperitoneal injection of cecal slurry. At 1 hour after sepsis induction, a single dose of 40 µg/kg recombinant mouse MFG-E8 or vehicle was administered via retro-orbital injection. All neonates were returned to their mothers as a group. At 10 hours after cecal slurry injection, pups were killed and blood and lung tissues were collected. Control mice underwent a similar procedure with the exception of cecal slurry intraperitoneal injection. RESULTS: Serum lactate dehydrogenase, IL-1ß, and IL-6 were significantly increased 10 hours after cecal slurry injection. Treatment with recombinant mouse MFG-E8 decreased these levels by 30%, 56%, and 37%, respectively. Lung morphology was significantly compromised in the vehicle group after cecal slurry injection, whereas the recombinant mouse MFG-E8-treated groups demonstrated a 48% improvement in the lung injury score. Lung IL-6 and MIP-2 protein levels were significantly reduced with recombinant mouse MFG-E8 treatment. Lung neutrophil infiltration as observed by Gr-1 staining and, TUNEL-positive cells were also significantly reduced with recombinant mouse MFG-E8 treatment. CONCLUSION: Treatment with recombinant mouse MFG-E8 attenuated inflammation and lung injury in murine neonatal sepsis. Thus, MFG-E8 could be developed as a possible therapy for neonatal sepsis.

Deficiency in milk fat globule-epidermal growth factor-factor 8 exacerbates organ injury and mortality in neonatal sepsis.

INTRODUCTION: Neonatal sepsis is a systemic inflammation occurring in neonates because of a proven infection within the first 28days of birth. It is the third leading cause of morbidity and mortality in the newborns. The mechanism(s) underlying the systemic inflammation in neonatal sepsis has not been completely understood. We hypothesize that the deficiency of milk fat globule-epidermal growth factor-factor 8 (MFG-E8), a protein commonly found in human milk, could be responsible for the increased inflammatory response leading to morbidity and mortality in neonatal sepsis. METHODS: Male and female newborn mice aged 5-7days were injected intraperitoneally with 0.9mg/g body weight cecal slurry (CS). At 10h after CS injection, they were euthanized, and blood, lungs and gut tissues were obtained for further analyses. Control newborn mice underwent similar procedures with the exception of the CS injection. In duplicate newborn mice after CS injection, they were returned to their respective cages with their mothers and were closely monitored for 7days and survival rate recorded. RESULTS: At 10h after CS injection, serum LDH in the MFG-E8 knockout (KO) newborn mice was significantly increased by 58% and serum IL-6, IL-1ß and TNF-α in the MFG-E8KO newborn mice were also significantly increased by 56%, 65%, and 105%, respectively, from wild type (WT) newborn mice. There were no significant difference between WT control and MFG-E8 control newborn mice. The lung architecture was severely damaged and a significant 162% increase in injury score was observed in the CS MFG-E8KO newborn mice. The MPO, TUNEL staining, and cytokine levels in the lungs and the intestine in CS MFG-E8KO newborn mice were significantly increased from CS WT newborn mice. Similarly, intestinal integrity was also compromised in the CS MFG-E8KO newborn mice. In a survival study, while the mortality rate within 7days was only 29% in the CS WT newborn mice, 80% of the CS MFG-E8KO newborn mice died during the same time period with the majority of mortality occurring within 48h. CONCLUSION: The deficiency in MFG-E8 caused increases in inflammation, tissue injury, neutrophil infiltration and apoptosis, which led to morbidity and mortality in murine neonatal sepsis. These studies suggest that MFG-E8 has a protective role in fighting against neonatal sepsis.

Milk fat globule-epidermal growth factor-factor VIII-derived peptide MSP68 is a cytoskeletal immunomodulator of neutrophils that inhibits Rac1.

BACKGROUND: Prolonged neutrophil infiltration leads to exaggerated inflammation and tissue damage during sepsis. Neutrophil migration requires rearrangement of their cytoskeleton. Milk fat globule-epidermal growth factor-factor VIII-derived short peptide 68 (MSP68) has recently been shown to be beneficial in sepsis-induced tissue injury and mortality. We hypothesize that MSP68 inhibits neutrophil migration by modulating small GTPase Rac1-dependent cytoskeletal rearrangements. METHODS: Bone marrow-derived neutrophils (BMDNs) or whole lung digest isolated neutrophils were isolated from 8 to 10 wk old C57BL/6 mice by Percoll density gradient centrifugation. The purity of BMDN was verified by flow cytometry with CD11b/Gr-1 staining. Neutrophils were stimulated with N-formylmethionine-leucine-phenylalanine (f-MLP) (10 nM) in the presence or absence of MSP68 at 10 nM or cecal ligation and puncture (CLP) was used to induce sepsis, and MSP68 was administered at 1 mg/kg intravenously. Cytoskeletal organization was assessed by phalloidin staining, followed by analysis using fluorescence microscopy. Activity of the Rac1 GTPase in f-MLP or CLP-activated BMDN in the presence or absence of MSP68 was assessed by GTPase enzyme-linked immunosorbent assay. Mitogen-activated protein (MAP) kinase activity was determined by western blot densitometry. RESULTS: BMDN treatment with f-MLP increased cytoskeletal remodeling as revealed by the localization of filamentous actin to the periphery of the neutrophil. By contrast, cells pretreated with MSP68 had considerably reduced filamentous actin polymerization. Cytoskeletal spreading is associated with the activation of the small GTPase Rac1. We found BMDN-treated with f-MLP or that were exposed to sepsis by CLP had increased Rac1 signaling, whereas the cells pretreated with MSP68 had significantly reduced Rac1 activation (P < 0.05). MAP kinases related to cell migration including pp38 and pERK were upregulated by treatment with f-MLP. Upregulation of these MAP kinases was also significantly reduced after pretreatment with MSP68 (P < 0.05). CONCLUSIONS: MSP68 downregulates actin cytoskeleton-dependent, Rac1-MAP kinase-mediated neutrophil motility. Thus, MSP68 is a novel therapeutic candidate for regulating inflammation and tissue damage caused by excessive neutrophil migration in sepsis.

Osteopontin Blockade Attenuates Renal Injury After Ischemia Reperfusion by Inhibiting NK Cell Infiltration.

Renal ischemia-reperfusion (RIR) injury is a common occurrence after major surgery and shock, leading to acute kidney injury (AKI). Osteopontin (OPN) is a secreted glycoprotein that acts as a proinflammatory cytokine and activator of T lymphocytes. We hypothesized that blockade of OPN reduces the severity of inflammation and injury in RIR. Renal ischemia was induced in adult C57BL/6 mice via bilateral clamping of renal pedicles for 35 min, followed by reperfusion for 24 h. Anti-OPN antibody (Ab), nonimmunized isotype immunoglobulin G, or normal saline was injected intravenously at the time of reperfusion. Blood and kidneys were collected for analysis. At 24 h after RIR, OPN mRNA and protein levels were significantly increased in renal tissue compared with sham mice. In serum, elevated levels of blood urea nitrogen and creatinine were reduced in anti-OPN Ab-treated mice compared with vehicle. Anti-OPN Ab-treated mice also had decreased mRNA levels of injury markers neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 compared with the vehicle. The histologic architecture and apoptosis of renal tissue were improved in the anti-OPN Ab-treated mice. In renal tissue, inflammatory cytokines interleukin 6 and tumor necrosis factor-α protein levels were reduced in the Ab-treated mice. Natural killer (NK) cell infiltration was decreased after anti-OPN Ab treatment, as was neutrophil infiltration, shown by reduced chemokine expression and Gr1 renal immunohistochemical staining. These findings demonstrate a beneficial role of OPN blockade in RIR associated with NK cell-mediated downregulation of inflammatory cytokines and chemokines. Administration of anti-OPN Ab may therefore serve as an immunomodulatory adjunct in the treatment of RIR-induced AKI.

Outcomes following operative vs. non-operative management of blunt traumatic pancreatic injuries: a retrospective multi-institutional study.

BACKGROUND: Traumatic pancreatic injuries are rare, and guidelines specifying management are controversial and difficult to apply in the acute clinical setting. Due to sparse data on these injuries, we carried out a retrospective review to determine outcomes following surgical or non-surgical management of traumatic pancreatic injuries. We hypothesize a higher morbidity and mortality rate in patients treated surgically when compared to patients treated non-surgically. METHODS: We performed a retrospective review of data from four trauma centers in New York from 1990-2014, comparing patients who had blunt traumatic pancreatic injuries who were managed operatively to those managed non-operatively. We compared continuous variables using the Mann-Whitney U test and categorical variables using the chi-square and Fisher's exact tests. Univariate analysis was performed to determine the possible confounding factors associated with mortality in both treatment groups. RESULTS: Twenty nine patients were managed operatively and 32 non-operatively. There was a significant difference between the operative and non-operative groups in median age (37.0 vs. 16.2 years, P = 0.016), grade of pancreatic injury (grade I; 30.8 vs. 85.2%, P value for all comparisons <0.0001), median injury severity score (ISS) (16.0 vs. 4.0, P = 0.002), blood transfusion (55.2 vs. 15.6%, P = 0.0012), other abdominal injuries (79.3 vs. 38.7%, P = 0.0014), pelvic fractures (17.2 vs. 0.00%, P = 0.020), intensive care unit (ICU) admission (86.2 vs. 50.0%, P = 0.003), median length of stay (LOS) (16.0 vs. 4.0 days, P <0.0001), and mortality (27.6 vs. 3.1%, P = 0.010). CONCLUSIONS: Patients with traumatic pancreatic injuries treated operatively were more severely injured and suffered greater complications than those treated non-operatively. The greater morbidity and mortality associated with these patients warrants further study to determine optimal triage strategies and which subset of patients is likely to benefit from surgery.

Type VI Choledochal Cyst-An Unusual Presentation of Jaundice.

Choledochal cysts involving the cystic duct are extremely rare, and are usually associated with cystic dilatations of the extrahepatic biliary tract. We describe a patient who presented with jaundice and was found to have a dilatation of the common bile duct on computed tomographic imaging, consistent with a choledochal cyst. He underwent a laparoscopic-converted-to-open cholecystectomy with excision of the choledochal cyst which was found to involve the cystic duct. Choledochal cysts involving the cystic duct are notably missing from the Todani classification. Although exceedingly rare, new cases of these types of cysts are being reported, in part due to advancement of diagnostic imaging modalities. We discuss the current classification scheme for choledochal cysts and we propose an expansion of this scheme.