Immature dendritic cell-derived exosomes rescue septic animals via milk fat globule epidermal growth factor-factor VIII [corrected].

Sepsis, a highly lethal systemic inflammatory syndrome, is associated with increases of proinflammatory cytokines (e.g., TNF-alpha, HMGB1) and the accumulation of apoptotic cells that have the potential to be detrimental. Depending on the timing and tissue, prevention of apoptosis in sepsis is beneficial; however, thwarting the development of secondary necrosis through the active removal of apoptotic cells by phagocytosis may offer a novel anti-sepsis therapy. Immature dendritic cells (IDCs) release exosomes that contain milk fat globule EGF factor VIII (MFGE8), a protein required to opsonize apoptotic cells for phagocytosis. In an experimental sepsis model using cecal ligation and puncture, we found that MFGE8 levels decreased in the spleen and blood, which was associated with impaired apoptotic cell clearance. Administration of IDC-derived exosomes promoted phagocytosis of apoptotic cells and significantly reduced mortality. Treatment with recombinant MFGE8 was equally protective, whereas MFGE8-deficient mice suffered from increased mortality. IDC exosomes also attenuated the release of proinflammatory cytokines in septic rats. Liberation of HMGB1, a nuclear protein that contributes to inflammation upon release from unengulfed apoptotic cells, was prevented by MFGE8-mediated phagocytosis in vitro. We conclude that IDC-derived exosomes attenuate the acute systemic inflammatory response in sepsis by enhancing apoptotic cell clearance via MFGE8.

Milk fat globule epidermal growth factor 8 attenuates acute lung injury in mice after intestinal ischemia and reperfusion.

RATIONALE: Milk fat globule epidermal growth factor 8 (MFG-E8) is a potent opsonin for the clearance of apoptotic cells and is produced by mononuclear cells of immune competent organs including the spleen and lungs. It attenuates chronic and acute inflammation such as autoimmune glomerulonephritis and bacterial sepsis by enhancing apoptotic cell clearance. Ischemia-reperfusion (I/R) injury of the gut results in severe inflammation, apoptosis, and remote organ damage, including acute lung injury (ALI). OBJECTIVES: To determine whether MFG-E8 attenuates intestinal and pulmonary inflammation after gut I/R. METHODS: Wild-type (WT) and MFG-E8(-/-) mice underwent superior mesenteric artery occlusion for 90 minutes, followed by reperfusion for 4 hours. A group of WT mice was treated with 0.4 microg/20 g recombinant murine MFG-E8 (rmMFG-E8) at the beginning of reperfusion. Four hours after reperfusion, MFG-E8, cytokines, myeloperoxidase activity, apoptosis, and histopathology were assessed. A 24-hour survival study was conducted in rmMFG-E8- and vehicle-treated WT mice. MEASUREMENTS AND MAIN RESULTS: Mesenteric I/R caused severe widespread injury and inflammation of the small intestines and remote organs, including the lungs. MFG-E8 levels decreased in the spleen and lungs by 50 to 60%, suggesting impaired apoptotic cell clearance. Treatment with rmMFG-E8 significantly suppressed inflammation (TNF-alpha, IL-6, IL-1beta, and myeloperoxidase) and injury of the lungs, liver, and kidneys. MFG-E8-deficient mice suffered from greatly increased inflammation and potentiated ALI, whereas treatment with rmMFG-E8 significantly improved the survival in WT mice. CONCLUSIONS: MFG-E8 attenuates inflammation and ALI after gut I/R and may represent a novel therapeutic agent.

A validated value-based model to improve hospital-wide perioperative outcomes: adaptability to combined medical/surgical inpatient cohorts.

OBJECTIVES: Authors hypothesized that building safe hospital systems to improve value-based surgical outcomes is predicated on workflow redesign for dynamic risk stratification, coupled with "real-time" mitigation of risk. We developed a comanagement model for hospitalized surgical cohort, and determined whether this iterative process redesign for surgery will be adaptable to disparate hospital systems and will be beneficial for combined medical/surgical adult inpatients. CONTEXT: Concerns about preventable harm in hospitalized patients have generated a plethora of both, process-driven and outcome-based strategies in US Healthcare. Although comparison between hospitals is a common mechanism to drive quality, other innovative approaches are needed for real-time risk mitigation to improve outcomes. METHODS: Prospective implementation of Surgical Continuum of Care (SCoC) model in hospitals initially for surgery patients; subsequently Continuum of Care (CoC) for medical/surgical population. Redesign of hospital care delivery model: patient cohorting, floor-based team building, and intensivist/hospitalist staffing of progressive care unit (PCU). Work flow redesign for clinical effectiveness: multidisciplinary team rounds, acuity stratified care rounding based on dynamic risk assessment into a novel HAWK (high risk)/DOVE (low risk) patient grouping, intensivist/hospitalist comanagement of surgical patients, and targeted response. STUDY: Pre- and postintervention with concurrent cohort control design. SETTING: Academic medical centers for SCoC and integrated health system hospital for CoC. PATIENT GROUPS: SCoC Pilot Study-Campus A: Preintervention control group 1998-2000, Intervention Group 2001-2004; Campus B: Comparator Control Group 1998-2004. SCoC Validation Study-Campus C: Preintervention Group 2001-2005; Intervention Group 2006-2008. CoC Study-Campus D: Hospital-wide Group 2009. METRICS: Mortality, length of stay (LOS): overall, surgical intensive care unit and PCU, readmission rates, and cost. Case mix index for risk adjustment. RESULTS: Total >100,000 admissions. There was a significant reduction in overall surgical mortality in both, pilot (P < 0.002) and validation (P < 0.02) SCoC studies and overall hospital mortality in the medical/surgical CoC study (risk-adjusted mortality index progressively declined in CoC study from 1.16 pre-CoC to 0.77 six months post-CoC implementation; significant at 75% confidence level). Case mix index was unchanged during study period in each campus. Nested study in validation cohort of hospital-wide versus surgery alone (observed/expected mortality index) demonstrated significant benefit to SCoC in intervention group. The mortality benefit was primarily derived from risk-stratified rounding and actively managing risk prone population in the PCU. Surgical intensive care unit, PCU, and total hospital patient-days significantly decreased in SCoC pilot study (P < 0.05), reflecting enhanced throughput. LOS reduction benefit persisted in SCoC validation and CoC studies. In addition to decreased LOS, cost savings were in PCU (range, $851,511-2,007,388) and top diagnosis-related groups, for example, $452 K/yr for diagnosis-related group 148. CONCLUSIONS: SCoC is patient-centered, outcomes-driven, value-based approach for hospital-wide surgical patient safety. The principles of this value paradigm are adaptable to other hospitals as demonstrated in our longitudinal study in 3 hospital systems, and the initial experience of CoC suggests that this model will have benefit beyond surgical hospital cohort.

Reversing established sepsis in rats with human vasoactive hormone adrenomedullin and its binding protein.

We recently demonstrated that early administration of rat adrenomedullin (AM), a vasoactive peptide, in combination with its binding protein (human AMBP-1) produces various beneficial effects in sepsis. Human AM is a 52-amino acid peptide, but rat AM differs from human AM, having only 50 amino acid residues, with two amino acid deletions and six substitutions. It remains unknown whether a combination of human AM and human AMBP-1 (AM/AMBP-1) is also beneficial in sepsis and, if so, whether human AM/AMBP-1 reverses established sepsis in rats. To test the effects of human AM/AMBP-1, we induced sepsis in male adult rats by cecal ligation and puncture (CLP). At 10 h after CLP (i.e., severe sepsis), human AM (12-48 microg/kg body weight) was administered in combination with human AMBP-1 (40-160 microg/kg body weight). Vehicle-treated animals received a nonspecific human plasma protein (albumin). Blood and intestinal samples were collected at 20 h for various measurements. In additional groups of septic animals, the gangrenous cecum was surgically excised at 20 h after CLP. The 10-day survival was recorded. Our results showed that tissue injury, as evidenced by increased levels of transaminases and lactate, was present at 20 h after CLP. Proinflammatory cytokines tumor necrosis factor-alpha and interleukin-6 were significantly elevated. Gut barrier dysfunction, manifested by increased mucosal permeability to hydrophilic macromolecules and increased bacterial translocation to mesenteric lymph nodes, also occurred at 20 h after CLP. Administration of human AM/AMBP-1 in established sepsis markedly attenuated tissue injury, reduced proinflammatory cytokine levels, ameliorated intestinal-barrier dysfunction, and improved the survival rate from 47% to 67%-80%. Thus, human AM/AMBP-1 can be further developed as a safe and effective therapy for patients with established sepsis.

Human ghrelin ameliorates organ injury and improves survival after radiation injury combined with severe sepsis.

In the terrorist radiation exposure scenario, radiation victims are likely to suffer from additional injuries such as sepsis. Our previous studies have shown that ghrelin is protective in sepsis. However, it remains unknown whether ghrelin ameliorates sepsis-induced organ injury and mortality after radiation exposure. The purpose of this study is to determine whether human ghrelin attenuates organ injury and improves survival in a rat model of radiation combined injury (RCI) and, if so, the potential mechanism responsible for the benefit. To study this, adult male rats were exposed to 5-Gy whole body irradiation followed by cecal ligation and puncture (CLP, a model of sepsis) 48 h thereafter. Human ghrelin (30 nmol/rat) or vehicle (saline) was infused intravenously via an osmotic minipump immediately after radiation exposure. Blood and tissue samples were collected at 20 h after RCI (68 h after irradiation or 20 h after CLP) for various measurements. To determine the longterm effect of human ghrelin after RCI, the gangrenous cecum was removed at 5 h after CLP and 10-d survival was recorded. In addition, vagotomy or sham vagotomy was performed in sham and RCI animals immediately prior to ghrelin administration, and various measurements were performed at 20 h after RCI. Our results showed that serum levels of ghrelin and its gene expression in the stomach were decreased markedly at 20 h after RCI. Administration of human ghrelin attenuated tissue injury markedly, reduced proinflammatory cytokine levels, decreased tissue myeloperoxidase activity, and improved survival after RCI. Furthermore, elevated plasma levels of norepinephrine (NE) after RCI were reduced significantly by ghrelin. However, vagotomy prevented ghrelin's beneficial effects after RCI. In conclusion, human ghrelin is beneficial in a rat model of RCI. The protective effect of human ghrelin appears to be attributed to re-balancing the dysregulated sympathetic/parasympathetic nervous systems.

Ghrelin hyporesponsiveness contributes to age-related hyperinflammation in septic shock.

OBJECTIVE: To test the hypothesis that hyporesponsiveness to ghrelin due to reduced growth hormone (GH) contributes to the aging-related hyperinflammatory state in sepsis. SUMMARY BACKGROUND DATA: Sepsis and septic shock are a serious problem, particularly in the geriatric population. Ghrelin is an endogenous ligand for the GH secretagogue receptor 1a (GHSR1a, ie, ghrelin receptor). The decline in GH with age is directly associated with many adverse changes that occur with aging. However, the role of GH, ghrelin, and GHSR1a in the age-associated vulnerability to sepsis remains unknown. METHODS: Male Fischer 344 rats (young: 3 months; aged: 24 months) were used. Plasma GH levels, ghrelin receptor expression, and neuronal activity in the parasympathostimulatory nuclei of the brain stem in normal young and aged animals were measured. Endotoxemia was induced by intravenous injection of lipopolysaccharide (LPS, 15 mg/kg BW). RESULTS: While LPS-induced release of proinflammatory cytokines from macrophages isolated from aged rats decreased, LPS injection resulted in an in vivo hyperinflammatory state. GH levels were lower in aged rats, which was associated with lower expression of GHSR1a in the dorsal vagal complex and a decrease in parasympathostimulatory neuronal activity. GHSR1a antagonist elevated LPS-induced cytokine release in young rats. GH increased GHSR-1a expression in the dorsal vagal complex in aged rats. Coadministration of ghrelin and GH, but not ghrelin alone or GH alone, markedly reduced cytokine levels and organ injury after endotoxemia in aged rats, which was associated with significantly elevated parasympathostimulatory neuronal activity. CONCLUSIONS: These findings suggest that the reduced central (brain) responsiveness to ghrelin due to the decreased GH, plays a major role in producing the hyperinflammatory state, resulting in severe organ injuries and high mortality after endotoxemia in aged animals. Ghrelin and GH can be developed as a novel therapy for sepsis in the geriatric population.

Human adrenomedullin and its binding protein attenuate organ injury and reduce mortality after hepatic ischemia-reperfusion.

OBJECTIVE: To determine whether administration of a vasoactive peptide, human adrenomedullin (AM), in combination with its binding protein (ie, AMBP-1), prevents or minimizes hepatic ischemia-reperfusion (I/R) injury. SUMMARY BACKGROUND DATA: Hepatic I/R injury results from tissue hypoxia and subsequent inflammatory responses. Even though numerous pharmacological modalities and substances have been studied to reduce I/R-induced mortality, none have been entirely successful. We have shown that administration of AM/AMBP-1 produces significant beneficial effects under various pathophysiological conditions. However, it remains unknown if human AM/AMBP-1 has any protective effects on hepatic I/R-induced tissue damage and mortality. METHODS: Seventy percent hepatic ischemia was induced in male adult rats by placing a microvascular clip across the hilum of the left and median lobes for 90 minutes. After removing the clip, human AM alone, human AMBP-1 alone, human AM in combination with human AMBP-1 or vehicle was administered intravenously over a period of 30 minutes. Blood and tissue samples were collected 4 hours after reperfusion for various measurements. In additional groups of animals, the nonischemic liver lobes were resected at the end of 90-minute ischemia. The animals were monitored for 7 days and survival was recorded. RESULTS: After hepatic I/R, plasma levels of AM were significantly increased, whereas AMBP-1 levels were markedly decreased. Likewise, gene expression of AM in the liver was increased significantly, whereas AMBP-1 expression was markedly decreased. Administration of AM in combination with AMBP-1 immediately after the onset of reperfusion down-regulated inflammatory cytokines, decreased hepatic neutrophil infiltration, inhibited liver cell apoptosis and necrosis, and reduced liver injury and mortality in a rat model of hepatic I/R. On the other hand, administration of human AM alone or human AMBP-1 alone after hepatic I/R failed to produce significant protection. CONCLUSIONS: Human AM/AMBP-1 may be a novel treatment to attenuate tissue injury after an episode of hepatic ischemia.

Orexigenic hormone ghrelin ameliorates gut barrier dysfunction in sepsis in rats.

OBJECTIVES: We have recently shown that ghrelin, a novel orexigenic hormone, is reduced in sepsis. Ghrelin treatment, mediated through ghrelin receptors in the brain, attenuates sepsis-induced inflammation and mortality. Gut barrier dysfunction is common in sepsis. High-mobility group B1 (HMGB1) increases gut permeability both in vitro and in vivo. However, it remains unknown whether ghrelin has any effects on HMGB1 and gut barrier function in sepsis. We hypothesized that ghrelin decreases HMGB1 release and attenuates sepsis-induced gut barrier dysfunction through central ghrelin receptors. DESIGN: Prospective, controlled, and randomized animal study. SETTING: A research institute laboratory. SUBJECTS: Male adult Sprague-Dawley rats (275-325 g). INTERVENTIONS: Cecal ligation and puncture (CLP) followed by injection/infusion of ghrelin. MEASUREMENTS AND MAIN RESULTS: Five hours after CLP, a bolus intravenous injection of 2 nmol of ghrelin was followed by a continuous infusion of 12 nmol of ghrelin via an osmotic mini-pump for 15 hrs. Twenty hours after CLP, brain ghrelin levels, serum HMGB1 levels, ileal mucosal permeability to fluorescein isothiocyanate dextran, bacterial counts in the mesenteric lymph nodes complex, and gut water content were determined. In additional groups of animals, bilateral trunk vagotomy was performed at 5 hrs after CLP before ghrelin injection. Furthermore, to confirm the role of central ghrelin receptors in ghrelin's effect, ghrelin (1 nmol) was administered through intracerebroventricular injection at 5 hrs after CLP. Our results showed that brain levels of ghrelin decreased by 34% at 20 hrs after CLP. Intravenous administration of ghrelin completely restored brain levels of ghrelin, significantly reduced the elevated HMGB1 levels, and attenuated gut barrier dysfunction. Vagotomy eliminated ghrelin's inhibition of HMGB1 and attenuation of gut barrier dysfunction. Intracerebroventricular injection of ghrelin decreased serum HMGB1 levels and ameliorated gut barrier dysfunction. CONCLUSIONS: Ghrelin reduces serum HMGB1 levels and ameliorates gut barrier dysfunction in sepsis by vagus nerve activation via central ghrelin receptors. Ghrelin can be further developed as a novel agent to protect gut barrier function in sepsis.

Pro-inflammatory cytokines from Kupffer cells downregulate hepatocyte expression of adrenomedullin binding protein-1.

Polymicrobial sepsis is characterized by an early, hyperdynamic phase followed by a late hypodynamic phase. Adrenomedullin (AM), a vasodilatory peptide, inhibits this transition from the early phase to the late phase. Adrenomedullin binding protein-1 (AMBP-1) enhances AM-mediated activities. The decrease of AMBP-1 levels in late sepsis reduces the vascular response to AM and produces the hypodynamic phase. Studies have indicated that the administration of LPS downregulates AMBP-1 production in the liver. Since hepatocytes are the primary source of AMBP-1 biosynthesis in the liver, we employed a co-culture strategy using hepatocyte and Kupffer cells to determine whether LPS directly or by increasing pro-inflammatory cytokines from Kupffer cells downregulates AMBP-1 production. Hepatocytes and Kupffer cells isolated from rats were co-cultured and treated with LPS for 24 h. LPS significantly attenuated AMBP-1 protein expression in a dose-dependent manner. Since AMBP-1 is basically a secretory protein, cell supernatants from co-culture cells treated with LPS were examined for AMBP-1 protein levels. LPS treatment caused a dose related decrease in AMBP-1 protein secretion. Similarly, LPS treatment produced a significant decrease in AMBP-1 protein expression in hepatocytes and Kupffer cells cultured using transwell inserts. LPS had no direct effect on AMBP-1 levels in cultured hepatocytes or Kupffer cells alone. To confirm that the observed effects in co-culture were due to the cytokines released from Kupffer cells, hepatocytes were treated with IL-1beta or TNF-alpha for 24 h and AMBP-1 expression was examined. The results indicated that both cytokines significantly inhibited AMBP-1 protein levels. Thus, pro-inflammatory cytokines released from Kupffer cells are responsible for downregulation of AMBP-1.

Human vasoactive hormone adrenomedullin and its binding protein rescue experimental animals from shock.

We recently discovered that vascular responsiveness to adrenomedullin (AM), a vasoactive hormone, decreases after hemorrhage, which is markedly improved by the addition of its binding protein AMBP-1. One obstacle hampering the development of AM/AMBP-1 as resuscitation agents in trauma victims is the potential immunogenicity of rat proteins in humans. Although less potent than rat AM, human AM has been shown to increase organ perfusion in rats. We therefore hypothesized that administration of human AM/AMBP-1 improves organ function and survival after severe blood loss in rats. To test this, male Sprague-Dawley rats were bled to and maintained at an MAP of 40 mmHg for 90 min. They were then resuscitated with an equal volume of shed blood in the form of Ringer's lactate (i.e., low-volume resuscitation) over 60 min. At 15 min after the beginning of resuscitation, human AM/AMBP-1 (12/40 or 48/160 microg/kg BW) were administered intravenously over 45 min. Various pathophysiological parameters were measured 4h after resuscitation. In additional groups of animals, a 12-day survival study was conducted. Our result showed that tissue injury as evidenced by increased levels of transaminases, lactate, and creatinine, was present at 4h after hemorrhage and resuscitation. Moreover, pro-inflammatory cytokines TNF-alpha and IL-6 were also significantly elevated. Administration of AM/AMBP-1 markedly attenuated tissue injury, reduced cytokine levels, and improved the survival rate from 29% (vehicle) to 62% (low-dose) or 70% (high-dose). However, neither human AM alone nor human AMBP-1 alone prevented the significant increase in ALT, AST, lactate and creatinine at 4h after the completion of hemorrhage and resuscitation. Moreover, the half-life of human AM and human AMBP-1 in rats was 35.8 min and 1.68 h, respectively. Thus, administration of human AM/AMBP-1 may be a useful approach for attenuating organ injury, and reducing mortality after hemorrhagic shock.

Maturation-induced down-regulation of MFG-E8 impairs apoptotic cell clearance and enhances endotoxin response.

In sepsis, phagocytosis and the killing of bacteria by phagocytes are important. Similarly, the clearance of accumulating apoptotic cells is critical in maintaining normal immunity. Upon maturation, peritoneal macrophages (PM) become a major source of proinflammatory cytokines, while losing their efficacy of phagocytosis. However, the underlying mechanism remains unknown. Here we investigated the differential effects of apoptotic thymocytes (AoTC) on TNF-alpha release in immature thioglycolate-elicited PM (TGPM) and mature resident PM (RPM) in vitro by culturing them with or without AoTC and/or LPS. MFG-E8 expression was assessed using Western blotting and the ability to engulf AoTC was determined histologically. Cytokine secretion was measured by ELISA. MAP kinase phosphorylation was assessed using Western blotting. Mature RPM express <50% of TGPM MFG-E8 levels and have a 30% lower capacity to clear AoTC. The proinflammatory response (TNF-alpha release) to LPS is 5 times higher, and the capability to phagocytose is decreased along with further down-regulation of MFG-E8 after LPS-stimulation. RPMs also lack phagocytosis-induced inhibition of TNF-alpha release after LPS stimulation. LPS-induced phosphorylation of ERK1/2, p38 and JNK is more enhanced in RPM compared to TGPM. MFG-E8-mediated apoptotic cell phagocytosis results in an inhibition of MAPK and NFkappaB signaling pathways. Differential MAPK activation may play a role in the enhanced LPS responsiveness of RPM and the lack of MFG-E8 impedes post-phagocytic suppression of LPS-response through the inhibition of those signaling pathways. These results provide a potential mechanistic insight into the benefit of promoting apoptotic cell clearance via MFG-E8 under inflammatory conditions.

Perception of Patient Safety Culture among Health-care Providers in a Tertiary Care Hospital, South India.

INTRODUCTION: Patient safety is a global concern and is the most important domains of health-care quality. Medical error is a major patient safety concern, causing increase in health-care cost due to mortality, morbidity, or prolonged hospital stay. AIM: The aim of the study was to assess the perceptions on patient safety culture among health-care providers (HCPs) at a public sector tertiary care hospital in South India. SETTINGS AND DESIGN: A hospital-based cross-sectional study was conducted 1 year after patient safety initiatives were implemented. MATERIALS AND METHODS: Participants were selected through proportionate stratified random sampling. The Hospital Survey on Patient Safety Culture was used to assess perception of patient safety culture. Responses were collected on a Likert scale and were categorized into four types as negative, neutral, positive response, and nonresponse. STATISTICAL ANALYSIS USED: The data were entered in EpiData Version 3.1 and analyzed using SPSS Version 17. "Composite positive response rate" for the various dimensions was calculated. RESULTS: The overall response rate in the study was 91.6%. Average composite positive response rate was 58%, and it varied among different cadres of HCPs ranged from 53% to 61%. The dimensions "teamwork within the unit," "organizational learning and continuous improvement," and "supervisor or officer-in-charge expectations" showed highest positive responses (80.1%, 77.8%, and 71.5%, respectively). CONCLUSIONS: This survey conducted after implementation of patient safety drive showed that, in many dimensions, the patient safety culture has taken roots. The dimensions such as "hand-off and transitions," "frequency of events reporting," and "communication openness" had scope for further improvement.

Adrenomedullin and adrenomedullin binding protein-1 prevent acute lung injury after gut ischemia-reperfusion.

BACKGROUND: Ischemic bowel remains a critical problem, resulting in up to 80% mortality. Acute lung injury, a common complication after intestinal ischemia/reperfusion (I/R), might be responsible for such a high mortality rate. Our previous studies have shown that administration of a novel vasoactive peptide adrenomedullin (AM) and its binding protein (AMBP-1) reduces the systemic inflammatory response in rat models of both hemorrhage and sepsis. It remains unknown whether administration of AM/AMBP-1 has any protective effects on intestinal I/R-induced acute lung injury. We hypothesized that administration of AM/AMBP-1 after intestinal I/R prevents acute lung injury through downregulation of proinflammatory cytokines. STUDY DESIGN: Intestinal I/R was induced by placing a microvascular clip across superior mesenteric artery (SMA) for 90 minutes in adult male Sprague-Dawley rats (275 to 325 g). On release of the SMA clamp, the animals were treated with either AM (12 mug/kg body weight) in combination with AMBP-1 (40 microg/kg body weight) or vehicle (1 mL normal saline) during a period of 30 minutes through a femoral vein catheter. Lung samples were collected at 4 hours after treatment or sham operation. Lung injury was assessed by examining lung water content, morphologic changes, and granulocyte myeloperoxidase activity. Tumor necrosis factor-alpha and interleukin-6 gene expression and their protein levels in the lungs were measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. In additional groups of animals, AM/AMBP-1 or vehicle was administered at 1 hour after onset of reperfusion. Lung histology was examined at 3 hours after treatment. RESULTS: Intestinal I/R induced considerable lung injury, as characterized by lung edema, histopathologic changes, increased myeloperoxidase activity, and proinflammatory cytokines (tumor necrosis factor-alpha and interleukin-6) levels in the lungs. Administration of AM/AMBP-1 after ischemia mitigated lung injury and dramatically downregulated proinflammatory cytokines. Lung injury was also ameliorated by delayed AM/AMBP-1 treatment as evidenced by improvement in lung histology. CONCLUSIONS: AM/AMBP-1 can be developed as a novel treatment to attenuate acute lung injury after an episode of gut ischemia. The protective effect of AM/AMBP-1 appears to be mediated through downregulation of proinflammatory cytokines.

Fate of retained capsule: a pathognomonic for surgery.

Since its introduction in 2001, Wireless Video Capsule enteroscopy is gaining acceptance due to its high diagnostic potential and minimal risk. In some centers, it offers an alternative approach to visualize the small intestine and to evaluate patients with suspected small bowel disease. We present a series of known complications of this procedure and call for a more proactive role in the management of retained capsule.

Cryotherapy in the treatment of liver metastases from colorectal cancer.

Although hepatic resection remains the treatment of choice for metastatic disease to the liver from colorectal cancer, the procedure is only possible for approximately 10% of patients. Ninety percent of patients with liver metastases ultimately die of liver failure. Thus, attention has turned to other, locoregional techniques that may be used alone or in conjunction with resection to increase the eligibility for some type of surgical, potentially curative treatment. One such option is cryotherapy. This review provides technical, physiologic, and outcome information regarding this technique. Semin Oncol 29:183-191.

Combination tramadol plus acetaminophen for postsurgical pain.

BACKGROUND: This multicenter, randomized, double-blind, active- and placebo-controlled trial evaluated tramadol plus acetaminophen (APAP) for orthopedic (n = 153) and abdominal (n = 152) postsurgical pain. METHODS: Patients with moderate pain or greater were randomized to an initial two tablets of 37.5 mg tramadol plus 325 mg APAP (n = 98), codeine 30 mg plus APAP 300 mg (n = 109), or placebo (n = 98); thereafter, they received 1 to 2 tablets every 4 to 6 hours as needed for pain for 6 days. Outcome measures were pain relief and pain intensity, total pain relief, sum of pain intensity differences, and sum of pain relief and pain intensity differences during 4 hours and the daily averages. RESULTS: Tramadol plus APAP was superior to placebo for total pain relief, sum of pain intensity differences, and sum of pain relief and pain intensity differences (P < or =0.015); tramadol plus APAP and codeine plus APAP did not separate (P > or=0.281). For average daily pain relief, average daily pain intensity, and overall medication assessment, tramadol plus APAP was superior to placebo (P < or =0.038); codeine plus APAP did not separate from placebo (P > or =0.125). Discontinuation because of adverse events occurred in 8.2% of tramadol plus APAP, 10.1% of codeine plus APAP, and 3.0% of placebo patients. Except for constipation (4.1% tramadol plus APAP vs 10.1% codeine plus APAP) and vomiting (9.2% vs 14.7%, respectively), adverse events were similar for active treatments. CONCLUSIONS: Tramadol plus APAP (mean dose 4.4 tablets) was effective and well tolerated for postsurgical pain and showed better tolerability than did codeine plus APAP.

Techniques for radiofrequency ablation of head and neck tumors.

OBJECTIVES: To describe the various techniques that have been developed for application of radiofrequency ablation in the palliative treatment of recurrent and advanced head and neck malignant tumors. DESIGN: Case series with a follow-up of 3 to 18 months. SETTING: Faculty practice, research protocol, tertiary care academic medical center. PATIENTS: Fifteen treatments were administered over a 3-year period to 12 patients with advanced and/or recurrent tumors. Eleven tumors were squamous cell carcinomas of the oral cavity, oropharynx, and maxillary sinus, and 1 tumor was a medullary thyroid carcinoma. Three of the 12 patients were treated on 2 separate occasions. Patients were selected as a referred sample and sent specifically for treatment with radiofrequency ablation because they were not candidates for the standard curative options of radiation or surgery. No patient refused enrollment, nor were any patients withdrawn because of adverse events. INTERVENTION: Radiofrequency ablation is a method of localized hyperthermia resulting in tissue necrosis. Ninety to 150 W of energy is applied, achieving intratumoral temperatures of 60 to 110 degrees C for 5 to 15 minutes per ablation. Techniques have been developed to apply radiofrequency ablation under direct vision, endoscopically, percutaneously, and with ultrasound and computed tomographic guidance. RESULTS: The radiofrequency ablation probe was accurately placed and treatment administered on 15 occasions. No perioperative deaths occurred. One patient suffered a stroke. Subjective patient improvement was reported with regard to pain (n=9), appearance (n=3), and function (n=4).

Pivotal role of the alpha(2A)-adrenoceptor in producing inflammation and organ injury in a rat model of sepsis.

BACKGROUND: Norepinephrine (NE) modulates the responsiveness of macrophages to proinflammatory stimuli through the activation of adrenergic receptors (ARs). Being part of the stress response, early increases of NE in sepsis sustain adverse systemic inflammatory responses. The intestine is an important source of NE release in the early stage of cecal ligation and puncture (CLP)-induced sepsis in rats, which then stimulates TNF-alpha production in Kupffer cells (KCs) through the activation of the alpha(2)-AR. It is important to know which of the three alpha(2)-AR subtypes (i.e., alpha(2A), alpha(2B) or alpha(2C)) is responsible for the upregulation of TNF-alpha production. The aim of this study was to determine the contribution of alpha(2A)-AR in this process. METHODOLOGY/PRINCIPAL FINDINGS: Adult male rats underwent CLP and KCs were isolated 2 h later. Gene expression of alpha(2A)-AR was determined. In additional experiments, cultured KCs were incubated with NE with or without BRL-44408 maleate, a specific alpha(2A)-AR antagonist, and intraportal infusion of NE for 2 h with or without BRL-44408 maleate was carried out in normal animals. Finally, the impact of alpha(2A)-AR activation by NE was investigated under inflammatory conditions (i.e., endotoxemia and CLP). Gene expression of the alpha(2A)-AR subtype was significantly upregulated after CLP. NE increased the release of TNF-alpha in cultured KCs, which was specifically inhibited by the alpha(2A)-AR antagonist BRL-44408. Equally, intraportal NE infusion increased TNF-alpha gene expression in KCs and plasma TNF-alpha which was also abrogated by co-administration of BRL-44408. NE also potentiated LPS-induced TNF-alpha release via the alpha(2A)-AR in vitro and in vivo. This potentiation of TNF-alpha release by NE was mediated through the alpha(2A)-AR coupled Galphai protein and the activation of the p38 MAP kinase. Treatment of septic animals with BRL-44408 suppressed TNF-alpha, prevented multiple organ injury and significantly improved survival from 45% to 75%. CONCLUSIONS/SIGNIFICANCE: Our novel finding is that hyperresponsiveness to alpha(2)-AR stimulation observed in sepsis is primarily due to an increase in alpha(2A)-AR expression in KCs. This appears to be in part responsible for the increased proinflammatory response and ensuing organ injury in sepsis. These findings provide important feasibility information for further developing the alpha(2A)-AR antagonist as a new therapy for sepsis.

Orexigenic hormone ghrelin attenuates local and remote organ injury after intestinal ischemia-reperfusion.

BACKGROUND: Gut ischemia/reperfusion (I/R) injury is a serious condition in intensive care patients. Activation of immune cells adjacent to the huge endothelial cell surface area of the intestinal microvasculature produces initially local and then systemic inflammatory responses. Stimulation of the vagus nerve can rapidly attenuate systemic inflammatory responses through inhibiting the activation of macrophages and endothelial cells. Ghrelin, a novel orexigenic hormone, is produced predominately in the gastrointestinal system. Ghrelin receptors are expressed at a high density in the dorsal vagal complex of the brain stem. In this study, we investigated the regulation of the cholinergic anti-inflammatory pathway by the novel gastrointestinal hormone, ghrelin, after gut I/R. METHODS AND FINDINGS: Gut ischemia was induced by placing a microvascular clip across the superior mesenteric artery for 90 min in male adult rats. Our results showed that ghrelin levels were significantly reduced after gut I/R and that ghrelin administration inhibited pro-inflammatory cytokine release, reduced neutrophil infiltration, ameliorated intestinal barrier dysfunction, attenuated organ injury, and improved survival after gut I/R. Administration of a specific ghrelin receptor antagonist worsened gut I/R-induced organ injury and mortality. To determine whether ghrelin's beneficial effects after gut I/R require the intact vagus nerve, vagotomy was performed in sham and gut I/R animals immediately prior to the induction of gut ischemia. Our result showed that vagotomy completely eliminated ghrelin's beneficial effect after gut I/R. To further confirm that ghrelin's beneficial effects after gut I/R are mediated through the central nervous system, intracerebroventricular administration of ghrelin was performed at the beginning of reperfusion after 90-min gut ischemia. Our result showed that intracerebroventricular injection of ghrelin also protected the rats from gut I/R injury. CONCLUSIONS: These findings suggest that ghrelin attenuates excessive inflammation and reduces organ injury after gut I/R through activation of the cholinergic anti-inflammatory pathway.

Gut hyperpermiability after ischemia and reperfusion: attenuation with adrenomedullin and its binding protein treatment.

Ischemia bowel remains a critical problem resulting in up to 80% mortality. The loss of gut barrier function plays an important role. Our previous studies have shown that administration of adrenomedullin (AM), a novel vasoactive peptide, and its binding protein (AMBP-1), reduces the systemic inflammatory response and organ injury after systemic ischemia induced by hemorrhagic shock. However, it remains unknown whether administration of AM/AMBP-1 preserves gut barrier function after gut ischemia reperfusion (I/R). We therefore hypothesized that AM/AMBP-1 prevents structural and functional damages to the intestinal mucosa after gut I/R. To test this, gut ischemia was induced by placing a microvascular clip across the superior mesenteric artery (SMA) for 90 min in male adult rats. After release of the SMA clamp, AM (12 mug/kg BW) and AMBP-1 (40 mug/kg BW) in combination or vehicle (1-ml normal saline) were administered intravenously over a period of 30 min. The mucosal barrier function in the small intestine was assessed in an isolated everted ileum sac using fluorescein-isothiocyanate dextran (FD4) at 4 h after AM/AMBP-1 treatment. FD4 clearance was used as a measure of gut permeability. In additional groups of animals, blood and small intestine samples were collected at 4 h after the treatment. Morphological changes in the small intestine were assessed by H-E staining. Serum concentrations of alanine aminotransferase, aspartate aminotransferase, total bilirubin, direct bilirubin, lactate and lactate dehydrogenase were also assessed. The gene expression and protein levels of TNF-alpha in the small intestine were determined by RT-PCR and ELISA, respectively. Our results showed that administration of AM/AMBP-1 significantly attenuated the development of intestinal mucosal hyperpermeability during the reperfusion. Treatment with AM/AMBP-1 dramatically improved I/R-induced intestinal mucosal damages, attenuated remote organ injury, and downregulated gene expression and protein levels of TNF-alpha in the small intestine. In conclusion, AM/AMBP-1 attenuates structural and functional damages to the intestinal mucosa, and it appears to be a novel treatment for reperfusion injury after gut ischemia. The beneficial effect of AM/AMBP-1 on gut barrier function after I/R is associated with downregulation of TNF-alpha.