Immunopathology of terminal complement activation and complement C5 blockade creating a pro-survival and organ-protective phenotype in trauma

BACKGROUND AND PURPOSE

Traumatic haemorrhage (TH) is the leading cause of potentially preventable deaths that occur during the prehospital phase of care. No effective pharmacological therapeutics are available for critical TH patients yet. Here, we identify terminal complement activation (TCA) as a therapeutic target in combat casualties and evaluate the efficacy of a TCA inhibitor (nomacopan) on organ damage and survival in vivo.

EXPERIMENTAL APPROACH

Complement activation products and cytokines were analysed in plasma from 54 combat casualties. The correlations between activated complement pathway(s) and the clinical outcomes in trauma patients were assessed. Nomacopan was administered to rats subjected to lethal TH (blast injury and haemorrhagic shock). Effects of nomacopan on TH were determined using survival rate, organ damage, physiological parameters, and laboratory profiles.

KEY RESULTS

Early TCA was associated with systemic inflammatory responses and clinical outcomes in this trauma cohort. Lethal TH in the untreated rats induced early TCA that correlated with the severity of tissue damage and mortality. The addition of nomacopan to a damage-control resuscitation (DCR) protocol significantly inhibited TCA, decreased local and systemic inflammatory responses, improved haemodynamics and metabolism, attenuated tissue and organ damage, and increased survival.

CONCLUSION AND IMPLICATIONS

Previous findings of our and other groups revealed that early TCA represents a rational therapeutic target for trauma patients. Nomacopan as a pro-survival and organ-protective drug, could emerge as a promising adjunct to DCR that may significantly reduce the morbidity and mortality in severe TH patients while awaiting transport to critical care facilities.

Distal organ inflammation and injury after resuscitative endovascular balloon occlusion of the aorta in a porcine model of severe hemorrhagic shock

BACKGROUND AND OBJECTIVE

Resuscitative Endovascular Balloon Occlusion of Aorta (REBOA) has emerged as a potential life-saving maneuver for the management of non-compressible torso hemorrhage in trauma patients. Complete REBOA (cREBOA) is inherently associated with the burden of ischemia reperfusion injury (IRI) and organ dysfunction. However, the distal organ inflammation and its association with organ injury have been little investigated. This study was conducted to assess these adverse effects of cREBOA following massive hemorrhage in swine.

METHODS

Spontaneously breathing and consciously sedated Sinclair pigs were subjected to exponential hemorrhage of 65% total blood volume over 60 minutes. Animals were randomized into 3 groups (n = 7): (1) Positive control (PC) received immediate transfusion of shed blood after hemorrhage, (2) 30min-cREBOA (A30) received Zone 1 cREBOA for 30 minutes, and (3) 60min-cREBOA (A60) given Zone 1 cREBOA for 60 minutes. The A30 and A60 groups were followed by resuscitation with shed blood post-cREBOA and observed for 4h. Metabolic and hemodynamic effects, coagulation parameters, inflammatory and end organ consequences were monitored and assessed.

RESULTS

Compared with 30min-cREBOA, 60min-cREBOA resulted in (1) increased IL-6, TNF-α, and IL-1β in distal organs (kidney, jejunum, and liver) (p < 0.05) and decreased reduced glutathione in kidney and liver (p < 0.05), (2) leukopenia, neutropenia, and coagulopathy (p < 0.05), (3) blood pressure decline (p < 0.05), (4) metabolic acidosis and hyperkalemia (p < 0.05), and (5) histological injury of kidney and jejunum (p < 0.05) as well as higher levels of creatinine, AST, and ALT (p < 0.05).

CONCLUSION

30min-cREBOA seems to be a feasible and effective adjunct in supporting central perfusion during severe hemorrhage. However, prolonged cREBOA (60min) adverse effects such as distal organ inflammation and injury must be taken into serious consideration.

High Confinement Mode and Edge Localized Mode Characteristics in a Near-Unity Aspect Ratio Tokamak

Tokamak experiments at near-unity aspect ratio A≲1.2 offer new insights into the self-organized H-mode plasma confinement regime. In contrast to conventional A∼3 plasmas, the L-H power threshold P_{LH} is ∼15× higher than scaling predictions, and it is insensitive to magnetic topology, consistent with modeling. Edge localized mode (ELM) instabilities shift to lower toroidal mode numbers as A decreases. These ultralow-A operations enable heretofore inaccessible J_{edge}(R,t) measurements through an ELM that show a complex multimodal collapse and the ejection of a current-carrying filament.

Ceftriaxone attenuates acute cocaine-evoked dopaminergic neurotransmission in the nucleus accumbens of the rat

BACKGROUND AND PURPOSE

Ceftriaxone is a β-lactam antibiotic and glutamate transporter activator that reduces the reinforcing effects of psychostimulants. Ceftriaxone also reduces locomotor activation following acute psychostimulant exposure, suggesting that alterations in dopamine transmission in the nucleus accumbens contribute to its mechanism of action. In the present studies we tested the hypothesis that pretreatment with ceftriaxone disrupts acute cocaine-evoked dopaminergic neurotransmission in the nucleus accumbens.

EXPERIMENTAL APPROACH

Adult male Sprague-Dawley rats were pretreated with saline or ceftriaxone (200 mg kg(-1) , i.p. × 10 days) and then challenged with cocaine (15 mg kg(-1) , i.p.). Motor activity, dopamine efflux (via in vivo microdialysis) and protein levels of tyrosine hydroxylase (TH), the dopamine transporter and organic cation transporter as well as α-synuclein, Akt and GSK3β were analysed in the nucleus accumbens.

KEY RESULTS

Ceftriaxone-pretreated rats challenged with cocaine displayed reduced locomotor activity and accumbal dopamine efflux compared with saline-pretreated controls challenged with cocaine. The reduction in cocaine-evoked dopamine levels was not counteracted by excitatory amino acid transporter 2 blockade in the nucleus accumbens. Pretreatment with ceftriaxone increased Akt/GSK3β signalling in the nucleus accumbens and reduced levels of dopamine transporter, TH and phosphorylated α-synuclein, indicating that ceftriaxone affects numerous proteins involved in dopaminergic transmission.

CONCLUSIONS AND IMPLICATIONS

These results are the first evidence that ceftriaxone affects cocaine-evoked dopaminergic transmission, in addition to its well-described effects on glutamate, and suggest that its ability to attenuate cocaine-induced behaviours, such as psychomotor activity, is due in part to reduced dopaminergic neurotransmission in the nucleus accumbens.

Ceruloplasmin and Hypoferremia: Studies in Burn and Non-Burn Trauma Patients

OBJECTIVE

Normal iron handling appears to be disrupted in critically ill patients leading to hypoferremia that may contribute to systemic inflammation. Ceruloplasmin (Cp), an acute phase reactant protein that can convert ferrous iron to its less reactive ferric form facilitating binding to ferritin, has ferroxidase activity that is important to iron handling. Genetic absence of Cp decreases iron export resulting in iron accumulation in many organs. The objective of this study was to characterize iron metabolism and Cp activity in burn and non-burn trauma patients to determine if changes in Cp activity are a potential contributor to the observed hypoferremia.

MATERIAL AND METHODS

Under Brooke Army Medical Center Institutional Review Board approved protocols, serum or plasma was collected from burn and non-burn trauma patients on admission to the ICU and at times up to 14 days and measured for indices of iron status, Cp protein and oxidase activity and cytokines.

RESULTS

Burn patients showed evidence of anemia and normal or elevated ferritin levels. Plasma Cp oxidase activity in burn and trauma patients were markedly lower than controls on admission and increased to control levels by day 3, particularly in burn patients. Plasma cytokines were elevated throughout the 14 days study along with evidence of an oxidative stress. No significant differences in soluble transferrin receptor were noted among groups on admission, but levels in burn patients were lower than controls for the first 5 days after injury.

CONCLUSION

This study further established the hypoferremia and inflammation associated with burns and trauma. To our knowledge, this is the first study to show an early decrease in Cp oxidase activity in burn and non-burn trauma patients. The results support the hypothesis that transient loss of Cp activity contributes to hypoferremia and inflammation. Further studies are warranted to determine if decreased Cp activity increases the risk of iron-induced injury following therapeutic interventions such as transfusions with blood that has undergone prolonged storage in trauma resuscitation.

Effect of systemic matrix metalloproteinase inhibition on periodontal wound repair: a proof of concept trial

BACKGROUND

The adjunctive use of matrix metalloproteinase (MMP) inhibitors with scaling and root planing (SRP) promotes new attachment in patients with periodontal disease. This pilot study was designed to examine aspects of the biological response brought about by the MMP inhibitor low dose doxycycline (LDD) combined with access flap surgery (AFS) on the modulation of periodontal wound repair in patients with severe chronic periodontitis.

METHODS

Twenty-four subjects were enrolled into a 12-month, randomized, placebo-controlled, double-masked trial to evaluate clinical, biochemical, and microbial measures of disease in response to 6 months therapy of either placebo capsules + AFS or LDD (20 mg b.i.d.) + AFS. Clinical measures including probing depth (PD), clinical attachment levels (CAL), and bleeding on probing (BOP) as well as gingival crevicular fluid bone marker assessment (ICTP) and microbial DNA analysis (levels and proportions of 40 bacterial species) were performed at baseline and 3, 6, 9, and 12 months.

RESULTS

Patients treated with LDD + AFS showed more potent reductions in PD in surgically treated sites of >6 mm (P<0.05, 12 months). Furthermore, LDD + AFS resulted in greater reductions in ICTP levels compared to placebo + AFS. Rebounds in ICTP levels were noted when the drug was withdrawn. No statistical differences between the groups in mean counts were found for any pathogen tested.

CONCLUSIONS

This pilot study suggests that LDD in combination with AFS may improve the response of surgical therapy in reducing probing depth in severe chronic periodontal disease. LDD administration also tends to reduce local periodontal bone resorption during drug administration. The use of LDD did not appear to contribute to any significant shifts in the microbiota beyond that of surgery alone.

Creating a vision for your medical call center

MCC technologies and applications that can have a positive impact on managed care delivery are almost limitless. As you determine your vision, be sure to have in mind the following questions: (1) Do you simply want an efficient front end for receiving calls? (2) Do you want to offer triage services? (3) Is your organization ready for a fully functional "electronic physician's office?" Understand your organization's strategy. Where are you going, not only today but five years from now? That information is essential to determine your vision. Once established, your vision will help determine what you need and whether you should build or outsource. Vendors will assist in cost/benefit analysis of their equipment, but do not lose sight of internal factors such as "prior inclination" costs in the case of a nurse triage program. The technology is available to take your vision to its outer reaches. With the projected increase in utilization of call center services, don't let your organization be left behind!

Interference with testing for lysergic acid diethylamide

We found a high rate (4.2%) of positive results for lysergic acid diethylamide (LSD) by Emit in 1898 urine samples that were submitted primarily from psychiatric patients for drugs-of-abuse (DOA) testing. Specimens that tested positive for LSD by Emit subsequently tested negative for LSD with two RIAs. Furthermore, LSD was not detected in randomly selected Emit-positive urine samples by gas chromatography-mass spectrometry. Normal urine samples tested positive for LSD by Emit when they were supplemented with therapeutic medications that were prescribed for patients with positive urine LSD results by Emit. These therapeutic drugs interfered specifically with the Emit assay for LSD, since other Emit DOA tests were not affected by these medications at the tested concentrations.

Familial carriage of methicillin-resistant Staphylococcus aureus and subsequent infection in a premature neonate

During routine surveillance of patients in a Neonatal Intensive Care Unit (NICU), an alert infection-control practitioner confirmed the relationship of the index patient (sibling 3) who had a methicillin-resistant Staphylococcus aureus (MRSA) infection to an infant sibling (sibling 2) who had been admitted to the hospital 7 months previously with an MRSA infection. Cultures of nasal specimens obtained from the index patient's parents and two other siblings also yielded MRSA for two of the family members, the mother and sibling 1. The strains were typed by antibiogram, plasmid analysis, and genomic DNA typing. The isolates from sibling 1, sibling 2, the mother, and one isolate from sibling 3 were found to be identical by all techniques. The other isolates from sibling 3 shared the same genomic type but had no detectable plasmids. These findings suggest that transmission of this strain occurred at least three times within this family and that at least one family member was colonized with the same strain for 7 months or more. Recognition that family members may serve as reservoirs for nosocomial infections with MRSA raises important issues for infection control.

Drug findings in 'Driving Under the Influence of Drugs' cases: a problem of illicit drug use

Drug findings in 137 drug positive cases of Driving Under the Influence of Drugs (DUID) occurring in St. Louis, Missouri, U.S.A. from June 1983 through May 1986 are presented. Thirty-two different drugs were detected. A single agent was detected in only 34% (47/137) of cases. The most frequently encountered drugs, expressed as percent of positive cases, were: phencyclidine, 47%; marijuana, 47%; benzodiazepines, 22%; barbiturates, 15%; opiates, 11%; and cocaine, 9%. Most multiple drug cases involved popular illicit drug mixtures, such as cocaine and morphine (speedballs) or phencyclidine on marijuana (whack). All the drivers in this survey had displayed inappropriate or impaired operation of a motor vehicle to the extent that a law enforcement officer had stopped and charged them for DUID. In at least 81% of the drug positive cases, persons impaired in the operation of a motor vehicle from a drug or drugs other than alcohol, were impaired not as the result of side effects of therapeutic drug use, but as the result of deliberate self intoxication with illicit or controlled substances.

Tissue disposition of cocaine in man: a report of five fatal poisonings

The disposition of cocaine in five cases of fatal poisoning are presented. The highest concentrations of cocaine were found in urine, kidney, spleen, brain, lung and skeletal muscle. Cocaine concentrations in these organs far exceeded those in blood. Cocaine was detected in all other specimens tested including: bile, heart, liver, vitreous and adipose tissue. These results are in agreement with limited, previously reported, tissue data, and indicate that when urine is not available, kidney, spleen, brain and/or lung should be the specimen of choice for cocaine detection.