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Dive into the research topics where Einar K. Kristoffersen is active.

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Featured researches published by Einar K. Kristoffersen.


PLOS ONE | 2011

Benefit from B-Lymphocyte Depletion Using the Anti-CD20 Antibody Rituximab in Chronic Fatigue Syndrome. A Double-Blind and Placebo-Controlled Study

Øystein Fluge; Ove Bruland; Kristin Risa; Anette Storstein; Einar K. Kristoffersen; Dipak Sapkota; Halvor Naess; Olav Dahl; Harald Nyland; Olav Mella

Background Chronic fatigue syndrome (CFS) is a disease of unknown aetiology. Major CFS symptom relief during cancer chemotherapy in a patient with synchronous CFS and lymphoma spurred a pilot study of B-lymphocyte depletion using the anti-CD20 antibody Rituximab, which demonstrated significant clinical response in three CFS patients. Methods and Findings In this double-blind, placebo-controlled phase II study (NCT00848692), 30 CFS patients were randomised to either Rituximab 500 mg/m2 or saline, given twice two weeks apart, with follow-up for 12 months. Xenotropic murine leukemia virus-related virus (XMRV) was not detected in any of the patients. The responses generally affected all CFS symptoms. Major or moderate overall response, defined as lasting improvements in self-reported Fatigue score during follow-up, was seen in 10 out of 15 patients (67%) in the Rituximab group and in two out of 15 patients (13%) in the Placebo group (p = 0.003). Mean response duration within the follow-up period for the 10 responders to Rituximab was 25 weeks (range 8–44). Four Rituximab patients had clinical response durations past the study period. General linear models for repeated measures of Fatigue scores during follow-up showed a significant interaction between time and intervention group (p = 0.018 for self-reported, and p = 0.024 for physician-assessed), with differences between the Rituximab and Placebo groups between 6–10 months after intervention. The primary end-point, defined as effect on self-reported Fatigue score 3 months after intervention, was negative. There were no serious adverse events. Two patients in the Rituximab group with pre-existing psoriasis experienced moderate psoriasis worsening. Conclusion The delayed responses starting from 2–7 months after Rituximab treatment, in spite of rapid B-cell depletion, suggests that CFS is an autoimmune disease and may be consistent with the gradual elimination of autoantibodies preceding clinical responses. The present findings will impact future research efforts in CFS. Trial registration ClinicalTrials.gov NCT00848692


Shock | 2014

Emergency whole-blood use in the field: a simplified protocol for collection and transfusion.

Geir Strandenes; Marc De Pasquale; Andrew P. Cap; Tor Hervig; Einar K. Kristoffersen; Matthew Hickey; Christopher Cordova; Olle Berséus; Håkon S. Eliassen; Logan Fisher

ABSTRACT Military experience and recent in vitro laboratory data provide a biological rationale for whole-blood use in the treatment of exsanguinating hemorrhage and have renewed interest in the reintroduction of fresh whole blood and cold-stored whole blood to patient care in austere environments. There is scant evidence to support, in a field environment, that a whole blood–based resuscitation strategy is superior to a crystalloid/colloid approach even when augmented by a limited number of red blood cell (RBC) and plasma units. Recent retrospective evidence suggests that, in this setting, resuscitation with a full compliment of RBCs, plasma, and platelets may offer an advantage, especially under conditions where evacuation is delayed. No current evacuation system, military or civilian, is capable of providing RBC, plasma, and platelet units in a prehospital environment, especially in austere settings. As a result, for the vast minority of casualties, in austere settings, with life-threatening hemorrhage, it is appropriate to consider a whole blood–based resuscitation approach to provide a balanced response to altered hemostasis and oxygen debt, with the goal of reducing the risk of death from hemorrhagic shock. To optimize the successful use of fresh whole blood/cold-stored whole blood in combat field environments, proper planning and frequent training to maximize efficiency and safety will be required. Combat medics will need proper protocol-based guidance and education if whole-blood collection and transfusion are to be successfully and safely performed in austere environments. In this article, we present the Norwegian Naval Special Operation Commando unit–specific remote damage control resuscitation protocol, which includes field collection and transfusion of whole blood. This protocol can serve as a template for others to use and adjust for their own military or civilian unit–specific needs and capabilities for care in austere environments.


Apmis | 1996

Human placental Fcγ-binding proteins in the maternofetal transfer of IgG

Einar K. Kristoffersen

Annexin II, a member of the annexin family of Ca2+ and phospholipid binding proteins, is present in human placenta. Placental annexin II has low affinity FcR activity, and is present as a heterotetramere on syncytiotrophoblast apical cell membrane extracellular surface. In addition to annexin II, transmembraneous leukocyte FcRIII is present on syncytiotrophoblast apical membrane. Either one, or both molecules may mediate the binding of IgG and thereby facilitate its transport through the syncytiotrophoblast layer. However, the presence of other maternal plasma proteins in syncytiotrophoblasts that are not transported to the human fetus is suggestive of nonspecific fluid phase endocytosis. The MHC class I like FcR, similar to the receptor found in neonatal rodent intestine, FcRn, is present intracellularly in human syncytiotrophoblasts, as is its light chain beta 2-microglobulin. The hFcRn is not detected on the apical plasma membrane. The placental hFcRn co-localizes with IgG in syncytiotrophoblast granules. It is likely that hFcRn binds and transcytoses IgG through the syncytiotrophoblast. Protected transfer of IgG may occur within syncytiotrophoblast endocytotic vesicles prior to release in the villous stroma and subsequent translocation into the lumen of fetal stem vessels by uptake and transport in endothelial caveolae.


Shock | 2014

LOW TITER GROUP O WHOLE BLOOD IN EMERGENCY SITUATIONS

Geir Strandenes; Olle Berséus; Andrew P. Cap; Tor Hervig; Michael C. Reade; Nicolas Prat; Anne Sailliol; Richard Gonzales; Clayton D. Simon; Paul M. Ness; Heidi Doughty; Philip C. Spinella; Einar K. Kristoffersen

ABSTRACT In past and ongoing military conflicts, the use of whole blood (WB) as a resuscitative product to treat trauma-induced shock and coagulopathy has been widely accepted as an alternative when availability of a balanced component-based transfusion strategy is restricted or lacking. In previous military conflicts, ABO group O blood from donors with low titers of anti-A/B blood group antibodies was favored. Now, several policies demand the exclusive use of ABO group–specific WB. In this short review, we argue that the overall risks, dangers, and consequences of “the ABO group–specific approach,” in emergencies, make the use of universal group O WB from donors with low titers of anti-A/B safer. Generally, risks with ABO group–specific transfusions are associated with in vivo destruction of the red blood cells transfused. The risk with group O WB is from the plasma transfused to ABO-incompatible patients. In the civilian setting, the risk of clinical hemolytic transfusion reactions (HTRs) due to ABO group–specific red blood cell transfusions is relatively low (approximately 1:80,000), but the consequences are frequently severe. Civilian risk of HTRs due to plasma incompatible transfusions, using titered donors, is approximately 1:120,000 but usually of mild to moderate severity. Emergency settings are often chaotic and resource limited, factors well known to increase the potential for human errors. Using ABO group–specific WB in emergencies may delay treatment because of needed ABO typing, increase the risk of clinical HTRs, and increase the severity of these reactions as well as increase the danger of underresuscitation due to lack of some ABO groups. When the clinical decision has been made to transfuse WB in patients with life-threatening hemorrhagic shock, we recommend the use of group O WB from donors with low anti-A/B titers when logistical constraints preclude the rapid availability of ABO group–specific WB and reliable group matching between donor and recipient is not feasible.


Acta Paediatrica | 2013

Incidence, clinical characteristics and outcome in Norwegian children with periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis syndrome; a population-based study.

Jostein Førsvoll; Einar K. Kristoffersen; Knut Øymar

To describe the incidence, epidemiology, clinical presentation and clinical outcome of children with the syndrome of periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) in a population‐based study.


Scandinavian Journal of Immunology | 1990

Fcγ Receptor Heterogeneity in the Human Placenta

Einar K. Kristoffersen; Elling Ulvestad; Christian A. Vedeler; Roald Matre

Fc receptors for IgG, FcRI (CD64), FcRII (OD32), and FcRIII (CD 16) in human placenta were studied by indirect immunohistochemistry using avidin biotin‐peroxidase complexes For the sunning of cryostat sections. The MoAb 32.2 against FcRI stained cells in the loose connective tissue of the placental villi. The MoAb IV3 (FcRII) and C1KM5 (FcRII) also stained stromal cells and in addition stained the endothelium of the placental villi. The MoAb anti‐Leu‐11b against FcRIII and BID6 against a 40‐kDa FcR from placenta stained both stromal cells and endothelium as well as the fetal trophoblasts lining the villi. The MoAb 3G8 (FcRIII) also stained trophoblasts and stromal cells but did not stain the endothelium


Journal of Neuroimmunology | 2005

The role of complement in myasthenia gravis: serological evidence of complement consumption in vivo

Fredrik Romi; Einar K. Kristoffersen; Johan A. Aarli; Nils Erik Gilhus

BACKGROUND Antibodies to the acetylcholine receptor (AChR) titin and the ryanodine receptor (RyR) occur in myasthenia gravis (MG). These antibodies are capable of complement activation in vitro. The involvement of the complement system should cause consumption of complement components such as C3 and C4 in vivo. MATERIALS AND METHODS Complement components C3 and C4 were assayed in sera from 78 AChR antibody-positive MG patients and 52 healthy controls. Forty-eight of the patient sera contained titin antibodies as well, and 20 were also RyR antibody-positive. RESULTS MG patients with AChR antibody concentrations above the median (11.2 nmol/l) had significantly lower mean C3 and C4 concentrations in serum compared to those with AChR antibody concentrations below the median. Titin antibody-positive MG patients, titin antibody-negative early-onset MG patients, titin antibody-negative late-onset MG patients, and controls had similar C3 and C4 concentrations. Nor did mean C3 and C4 concentrations differ in MG patients with RyR antibodies. Patients with severe MG (grades 4 and 5) had similar C3 and similar C4 levels compared to those with mild MG (grades 1 and 2). CONCLUSION An increased in vivo complement consumption was detected in MG patients with high AChR antibody concentrations, unrelated to MG severity and non-AChR muscle antibodies.


Journal of Neuro-oncology | 1998

Expression of annexin II in glioma cell lines and in brain tumor biopsies.

Svein J.T. Nygaard; Hans Kristian Haugland; Einar K. Kristoffersen; Morten Lund-Johansen; Ole Didrik Laerum; Ole-Bjørn Tysnes

Annexin II is a calcium and phospholipid binding protein and a substrate for protein-tyrosine kinases. Increased levels of annexin II are observed in various cancer cells and tissues, and the molecule has been proposed as a marker of malignancy in vivo. Annexin II was expressed in four glioma cell lines (D-54MG, D-37MG, U251MG and GaMG), as determined by Western blot analyses, immunofluorescence staining and flow cytometric measurements. In addition, annexin II expression was also found in cryostat sections obtained from 15 consecutive brain tumor biopsies: Ten were histologically classified as glioblastomas, one as an astrocytoma, two as meningiomas and two as brain metastases. Cultured spheroids from the glioma cell lines and from three of the glioblastoma biopsies showed lower levels of annexin II, than found in the monolayers of the cell lines and in the freshly cut biopsies. The annexin II expression of the cell lines were not found to be related to their proliferative, migratory or invasive properties. These findings indicate that although annexin II may serve as a marker of malignancy in vivo, its expression can be reduced in vitro, and appear unrelated to malignant features of glioma cell lines.


American Journal of Reproductive Immunology | 1996

Surface Annexin II on Placental Membranes of the Fetomaternal Interface

Einar K. Kristoffersen; Roald Matre

PROBLEM: The phospholipidbinding membrane protein annexin II has been demonstrated to possess FcR activity for IgG and has been localized to the outer part of the syncytiotrophoblast cell layer. The question has arisen whether annexin II is exposed on the surface of syncytiotrophoblast cells thus enabling it to take part in the transport of IgG across the maternal barrier.


Journal of Trauma-injury Infection and Critical Care | 2015

Freeze dried plasma and fresh red blood cells for civilian prehospital hemorrhagic shock resuscitation.

Geir Arne Sunde; Bjarne Vikenes; Geir Strandenes; Kjell-Christian Flo; Tor Hervig; Einar K. Kristoffersen; Jon-Kenneth Heltne

BACKGROUND The last decade of military trauma care has emphasized the role of blood products in the resuscitation of hemorrhaging patients. Damage-control resuscitation advocates decreased crystalloid use and reintroduces blood components as primary resuscitative fluids. The systematic use of blood products have been described in military settings, but reports describing the use of freeze dried plasma (FDP) or red blood cells (RBCs) in civilian prehospital care are few. We describe our preliminary results after implementing RBCs and FDP into our Helicopter Emergency Medical Service (HEMS). METHODS We collected data on the use of FDP (LyoPlas N–w (AB)) during a 12-month period from May 31, 2013, to May 30, 2014, before RBC (0Rh (D) negative) introduction in June 2014. FDP and RBCs were indicated in trauma and medical patients presenting with clinical significant hemorrhage on scene. Data were obtained from HEMS registry and patient records. RESULTS Our preliminary results show that FDP was used in 16 patients (88% males) during the first year. Main patient categories were blunt trauma (n = 5), penetrating trauma (n = 4), and nontrauma (n = 7). Ten patients (62%) were hypotensive with systolic blood pressures less than 90 mm Hg on scene. The majority (75%) received tranexamic acid. Of 14 patients admitted to the hospital, 11 received emergency surgery and 8 needed additional transfusions within the first 24 hours. No transfusion-related complications were recorded. Two of the FDP patients died on scene, and the remaining 14 patients were alive after 30 days. Early results from the recent introduction of RBC show that RBCs were given to four patients. Two patients (one penetrating trauma and one blunt trauma patient) died on scene because of exsanguination, while additional two patients (one blunt trauma patient and one with ruptured aortic aneurism) survived to hospital discharge. CONCLUSION Our small study indicates that introduction of FDP into civilian HEMS seems feasible and may be safe and that logistical and safety issues for the implementation of RBCs are solvable. FDP ensures both coagulation factors and volume replacement, has a potentially favorable safety profile, and may be superior to other types of plasma for prehospital use. Further prospective studies are needed to clarify the role of FDP (and RBCs) in civilian prehospital hemorrhagic shock resuscitation and to aid the development of standardized protocols for prehospital use of blood products. LEVEL OF EVIDENCE Therapeutic study, level V.

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Elling Ulvestad

Haukeland University Hospital

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Tor Hervig

Haukeland University Hospital

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Øystein Bruserud

Haukeland University Hospital

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Geir Strandenes

Haukeland University Hospital

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Guro Kristin Melve

Haukeland University Hospital

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Knut Øymar

Stavanger University Hospital

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