Motor Effects of Minimal Traumatic Brain Injury in Mice.

Traumatic brain injury (TBI) is considered to be the leading cause of disability and death among young people. Up to 30% of mTBI patients report motor impairments, such as altered coordination and impaired balance and gait. The objective of the present study was to characterize motor performance and motor learning changes, in order to achieve a more thorough understanding of the possible motor consequences of mTBI in humans. Mice were exposed to traumatic brain injury using the weight-drop model and subsequently subjected to a battery of behavioral motor tests. Immunohistochemistry was conducted in order to evaluate neuronal survival and synaptic connectivity. TBI mice showed a different walking pattern on the Erasmus ladder task, without any significant impairment in motor performance and motor learning. In the running wheels, mTBI mice showed reduced activity during the second dark phase and increased activity during the second light phase compared to the control mice. There was no difference in the sum of wheel revolutions throughout the experiment. On the Cat-Walk paradigm, the mice showed a wider frontal base of support post mTBI. The same mice spent a significantly greater percent of time standing on three paws post mTBI compared with controls. mTBI mice also showed a decrease in the number of neurons in the temporal cortex compared with the control group. In summary, mTBI mice suffered from mild motor impairments, minor changes in the circadian clock, and neuronal damage. A more in-depth examination of the mechanisms by which mTBI compensate for motor deficits is necessary.

A phase I clinical trial demonstrates that nfP2X7 -targeted antibodies provide a novel, safe and tolerable topical therapy for basal cell carcinoma.

BACKGROUND: Expression of P2X7 , an ATP-gated calcium channel, increases cancer cell proliferation and invasiveness. A variant of P2X7 (termed nfP2X7 ), in which a normally hidden epitope (E200) is exposed for antibody binding, is observed in a variety of different cancers. OBJECTIVES: To investigate the safety, tolerability and pharmacokinetics and assess indicative efficacy of a novel antibody ointment as a therapeutic for basal cell carcinoma (BCC). METHODS: An open-label, phase I clinical trial was undertaken at three dermatology clinics to evaluate the safety and tolerability of topical administration of an ointment containing 10% sheep polyclonal anti-nfP2X7 antibodies (BIL010t) to primary BCC lesions twice daily for 28 days. Twenty-one patients with primary BCC lesions at least 0·5 cm2 in area and less than 2·0 cm in diameter were enrolled. The primary end points were safety, tolerability and pharmacokinetics. Change in lesion size after treatment was determined and histology was performed on pretreatment and end-of-treatment (EOT) biopsies. RESULTS: Compliance was very high, with treatment being well tolerated. The most common adverse events were treatment site erythema, pruritus, dryness and pain. There was no evidence of systemic penetration of the sheep antibody. Lesions were measured prior to and after 28 days of treatment, with 65% of patients showing a reduction in lesion area, 20% showing no change and 15% showing an increase. Histopathology of post-treatment excision of lesion sites showed eight patients with stable disease, nine with partial response and three with complete response. CONCLUSIONS: Antibodies against nfP2X7 (BIL010t) provide a novel, safe and well-tolerated treatment for BCC.

Fap2 of Fusobacterium nucleatum is a galactose-inhibitable adhesin involved in coaggregation, cell adhesion, and preterm birth.

Fusobacterium nucleatum is a common oral anaerobe involved in periodontitis that is known to translocate and cause intrauterine infections. In the oral environment, F. nucleatum adheres to a large diversity of species, facilitating their colonization and creating biological bridges that stabilize the multispecies dental biofilm. Many of these interactions (called coadherences or coaggregations) are galactose sensitive. Galactose-sensitive interactions are also involved in the binding of F. nucleatum to host cells. Hemagglutination of some F. nucleatum strains is also galactose sensitive, suggesting that a single galactose-sensitive adhesin might mediate the interaction of fusobacteria with many partners and targets. In order to identify the fusobacterial galactose-sensitive adhesin, a system for transposon mutagenesis in fusobacteria was created. The mutant library was screened for hemagglutination deficiency, and three clones were isolated. All three clones were found to harbor the transposon in the gene coding for the Fap2 outer membrane autotransporter. The three fap2 mutants failed to show galactose-inhibitable coaggregation with Porphyromonas gingivalis and were defective in cell binding. A fap2 mutant also showed a 2-log reduction in murine placental colonization compared to that of the wild type. Our results suggest that Fap2 is a galactose-sensitive hemagglutinin and adhesin that is likely to play a role in the virulence of fusobacteria.

Antidote strategies to reverse anticoagulation with TB-402, a long-acting partial inhibitor of factor VIII.

BACKGROUND: TB-402 is a partially inhibiting antibody of factor VIII that is under development as a long-acting anticoagulant. PATIENTS AND METHODS: The reversibility of FVIII inhibition by TB-402 was evaluated in vitro after spiking with recombinant human FVIII (rhFVIII), human plasma-derived FVIII (hpdFVIII), recombinant activated human FVII (rhFVIIa), FVIII inhibitor bypassing activity (FEIBA), and prothrombin complex concentrate (PCC). Twelve subjects were randomized to placebo or 35 or 70 IU kg(-1) rhFVIII 48 h after a single dose of 620 µg kg(-1) TB-402. TB-402 concentrations, FVIII activity (FVIII:C), activated partial thromboplastin time (APTT) and thrombin generation were measured over a period of 8 weeks. RESULTS: In spiked samples, TB-402 inhibited FVIII:C by 30%, prolonged APTT by 4.5 s, and reduced the peak height in the thrombin generation assay to 56% ± 13% of the control value. In the presence of 10 µg mL(-1) TB-402, rhFVIII restored FVIII:C and APTT to the values obtained in the absence of TB-402. The inhibitory effect of TB-402 on thrombin generation was entirely reversed by rhFVIII, hpdFVIII, rhFVIIa, FEIBA, and PCC. In men, the mean half-life (t(1/2) ) of TB-402 was 14.2 days. TB-402 lowered the endogenous thrombin potential by 23% for ~ 35 days. Infusion of 35 IU kg(-1) rhFVIII had a marginal effect, whereas 70 IU kg(-1) rhFVIII restored FVIII:C, reduced APTT back to baseline for 9 h, and restored thrombin generation for ~ 3 h. CONCLUSIONS: TB-402 resulted in a stable long-term anticoagulant effect. rhFVIII and other procoagulants counteracted the effect of TB-402 temporarily, and may be effective antidotes for future clinical practice.

A phase I, dose-escalation study of TB-403, a monoclonal antibody directed against PlGF, in patients with advanced solid tumours.

BACKGROUND: TB-403 (RO 5323441), a humanised monoclonal antibody, is a novel antiangiogenesis agent directed against placental growth factor. The safety, pharmacokinetics (PK), and antitumour activity of TB-403 were assessed in a phase I, dose-escalation study in patients with advanced solid tumours. METHODS: Patients in sequential dose groups received either weekly doses of 1.25, 5.0, or 10 mg kg(-1) or doses of 20 or 30 mg kg(-1) every third week. RESULTS: Twenty-three patients were enrolled and received TB-403. The most common adverse events (AEs) were fatigue, constipation, pyrexia, dyspnoea, and nausea. One serious AE, a lung embolus in a patient with non-small cell lung cancer treated with 10 mg kg(-1) weekly, was deemed possibly related to TB-403. No dose-limiting toxicities were observed, and a maximum-tolerated dose was not reached. The PK parameters were dose linear and the terminal half-life values ranged from 9 to 14 days. Six patients exhibited stable disease for at least 8 weeks. Two patients, (oesophageal squamous cell carcinoma and pancreatic adenocarcinoma) both treated with 5 mg kg(-1) weekly, remained stable for 12 months. CONCLUSION: TB-403 treatment in this patient population is well tolerated, with a safety profile distinct from that of vascular endothelial growth factor-axis inhibitors.

Single intravenous administration of TB-402 for the prophylaxis of venous thromboembolism after total knee replacement: a dose-escalating, randomized, controlled trial.

BACKGROUND: TB-402 is a novel anticoagulant monoclonal antibody with a prolonged antithrombotic effect resulting from its partial factor (F)VIII inhibition and long half-life. We evaluated the efficacy and safety of a single administration of TB-402 for the prevention of venous thromboembolism (VTE) after total knee replacement (TKR). PATIENTS AND METHODS: This was a phase II, dose-escalating, randomized, enoxaparin-controlled, open-label study. Patients were post-operatively assigned to a single dose of TB-402 (0.3, 0.6 or 1.2 mg kg(-1)) or enoxaparin 40 mg for at least 10 days (n = 75 per group; 3:1 TB-402 to enoxaparin). The primary efficacy outcome was total VTE defined as asymptomatic deep vein thrombosis (DVT) detected by bilateral venography and symptomatic VTE by day 7 to 11. The principal safety outcome was the incidence of major bleeding and clinically relevant non-major bleeding. RESULTS: Total VTE was lower in all TB-402 groups compared with enoxaparin: 16.7%(95% CI 9.8-26.9), 23.9%(95% CI 15.3-35.3), 24.1%(95% CI 16.0-34.5) and 39.0%(95% CI 28.8-50.1) for TB-402 0.3, 0.6, 1.2 mg kg(-1) and enoxaparin, respectively (P = 0.003 for TB-402 0.3 mg kg(-1) vs. enoxaparin). The incidence of total VTE in the pooled TB-402 groups was 21.6% (95%CI 16.6-27.5), an absolute risk reduction vs. enoxaparin of 17.4% (95% CI 5.2-29.6). Major or clinically relevant non-major bleeding was observed in 3/75(4.0%), 4/74(5.4%), 7/87(8.0%) and 3/79(3.8%) patients for TB-402 0.3, 0.6, 1.2 mg kg(-1) and enoxaparin, respectively. CONCLUSIONS: TB-402, as a single post-operative administration, was associated with a lower rate of VTE in all doses tested, compared with enoxaparin. The incidence of major and clinically relevant non-major bleeding was similar to enoxaparin 40 mg for TB-402 0.3 and 0.6 mg kg(-1).

Photodynamic therapy of actinic keratoses with topical aminolevulinic acid hydrochloride and fluorescent blue light.

BACKGROUND: Aminolevulinic acid hydrochloride (ALA, Levulan) applied topically to actinic keratoses (AKs) leads to accumulation of the photosensitizer protoporphyrin IX, which, when activated by exposure to light, eradicates AKs. OBJECTIVE: We examined the safety and efficacy of photodynamic therapy using topical 20% ALA in a solution formulation and varying blue light doses to treat multiple AKs on the face and scalp. METHOD: This is a multicenter, investigator-blinded, randomized, vehicle-controlled study. RESULTS: Thirty-six patients with clinically typical AKs were treated with 20% ALA; 14 to 18 hours later, they were irradiated with a nonlaser fluorescent blue light source. With the optimal light dose of 10 J/cm(2), 88% of the AKs completely cleared 8 weeks after a single photodynamic treatment, compared with 6% after treatment with vehicle and light. CONCLUSION: Topical ALA PDT using a nonlaser, blue light source is an effective treatment for multiple AKs.

Rapid assessment of glycoprotein IIb/IIIa blockade with the platelet function analyzer (PFA-100) during percutaneous coronary intervention.

BACKGROUND: The platelet function analyzer PFA-100 (Dade Behring, Miami, Fla) evaluates platelet function by determining the time to occlusion of an aperture in a membrane coated with collagen and adenosine diphosphate or epinephrine as whole blood flows under shear stress conditions. Platelet aggregation causes aperture occlusion, and results are reported as closure time (CT). Interindividual variability is observed in the level of platelet inhibition achieved with use of the current abciximab dosing regimen (0.25-mg/kg bolus + 10-microg/min infusion for 12 hours). The relationships between specific levels of platelet inhibition and clinical efficacy and safety have not been fully established. METHODS AND RESULTS: We prospectively studied platelet function in 27 patients receiving abciximab during percutaneous coronary intervention. This evaluation included determinations of platelet-rich plasma aggregometry, receptor occupancy studies (D3 assay), and CT measurements at baseline and 10 minutes, 4 hours, 12 hours, and 24 hours after the bolus. All patients received abciximab, aspirin, and heparin; patients undergoing coronary stent implantation received aspirin and ticlopidine after the procedure. CT results were reported within 10 minutes after initiation of testing. For 96% of patients, CT was 300 seconds (maximum CT) immediately after abciximab bolus and remained so throughout the infusion. At 24 hours we observed variable recovery from platelet inhibition and in 72% of patients CT returned to normal (< or =130 seconds). CONCLUSIONS: Findings with the PFA-100 were similar to results observed with platelet aggregometry and receptor occupancy measurements. Most patients treated with abciximab exhibit normalized platelet function at 24 hours despite moderate levels of receptor occupancy, suggesting dissociation between occupancy and function.

Recombinant factor VIIa corrects prothrombin time in cirrhotic patients: a preliminary study.

BACKGROUND & AIMS: Cirrhotic patients with a prolonged prothrombin time (PT) are known to have low levels of factor VII. Because the current modalities to correct this problem are not ideal, recombinant factor VIIa (rFVIIa) may be useful in correcting the prolonged PT observed in the coagulopathy of cirrhosis. The aim of this study was to evaluate the effectiveness of rFVIIa in nonbleeding volunteer patients with the coagulopathy of cirrhosis. METHODS: A preliminary, single-center, dose-escalation trial was performed. Cirrhotic patients with a PT of > 2 seconds above the upper limit of the reference value received an intramuscular injection of vitamin K. Ten patients whose PT did not correct to within 2 seconds above the control of the upper limit of the reference value were given three successive dosages of rFVIIa (5, 20, and 80 micrograms/kg) during a 3-week period. RESULTS: The mean PT transiently corrected to normal in all three dosage groups. No adverse effects were noted. There was no evidence of the induction of disseminated intravascular coagulation. CONCLUSIONS: This preliminary trial shows rFVIIa to be effective in transiently reversing the prolonged PT in a select group of nonbleeding cirrhotic patients. These preliminary observations support conducting a large-scale efficacy trial.

Immunological aspects of recombinant factor VIIa (rFVIIa) in clinical use.

Patients, receiving rFVIIa for treatment of bleeding disorders, have been followed for specific antibody formation. No antibodies against FVII were demonstrated in 170 patients, with hemophilia, or with acquired inhibitors to clotting factors. Of 6 FVII-deficient patients, one overdosed patient developed antibodies to human FVII. There was no indication of de novo formation of antibodies to potential contaminating foreign protein, which could be correlated to the rFVIIa treatment. Except for the FVII-deficient population, which may represent a risk group, rFVIIa appears to be immunologically safe for use in patient groups with bleeding disorders, including hemophilia A and B patients.

Clinical experience with recombinant factor VIIa in patients with thrombocytopenia.

Platelets play a central role in primary hemostasis. The role of the coagulation mechanism during early stages of hemostasis is less clear, although increasing evidence is emerging indicating the ultimate importance of the factor VII (FVII)-tissue factor-dependent coagulation system in providing the first thrombin molecules necessary for the platelet activation to occur. Supporting this, early fibrin formation has been reported to occur within the bleeding time wound and infusion of recombinant FVIIa (rFIIa) has been shown to shorten the bleeding time in rabbits. We have investigated whether infusion of rFVIIa would enhance fibrin formation in bleeding time wounds in patients with thrombocytopenia as reflected by a shortening of the bleeding time. A reduction of the bleeding time was found in 55/105 cases (52%). The decrease was significantly more pronounced when the platelet count exceeded 20 x 10(9)/l. With the exception of an anaphylactoid reaction in 1 patient, no major adverse reactions related to the study drug were observed. Nine infusions of rFVIIa were given to 8 thrombocytopenic patients with overt bleeding. One patient received two infusions. Bleeding decreased in all patients and stopped in 6 patients.

Blocking of tissue factor pathway inhibitor (TFPI) shortens the bleeding time in rabbits with antibody induced haemophilia A.

Tissue factor (TF)/FVIIa initiates coagulation by activating factor IX (FIX) and factor X (FX). Tissue factor pathway inhibitor (TFPI)-FXa complexes form and inhibit TF/FVIIa. Blocking of TFPI may facilitate haemostasis initiated by FVIIa/TF thereby compensating for impaired FIX/FVIII-dependent coagulation. This hypothesis was tested in a study using rabbits made temporarily haemophilic by the injection of antibodies against FVIII. These rabbits were given i.v. injections of anti-TFPI IgG antibodies and 40 min later bleeding was initiated by cutting the nail including the apex of the cuticle. Injection of anti-TFPI IgG shortened the bleeding time significantly from 26 min to 11 min (normal mean bleeding time in non-haemophilia rabbits: 5 min). Treatment with anti-TFPI IgG also resulted in a shortening of the haemophilic aPTT to a level slightly longer than the normal aPTT. In addition, the prolonged dilute TF clotting time was shortened by the anti-TFPI IgG treatment. Thus, both bleeding and coagulation parameters indicated that blocking of TFPI may be potentially haemostatic in haemophilia.

Hospital administrators: the challenge of living in a glass house.

BACKGROUND: Public accountability is the watchword of the 1990s. A chief executive officer (CEO) has many "publics," internal and external, demanding accountability. Most have different agendas. Although much rhetoric is focused on quality, access and cost seem to be the real interests of most constituents. ISSUES: What tools help the CEO respond effectively in this environment? How useful will outcome measures be to the CEO in the current competitive environment? If outcome measures are not useful in gaining market share, do they have other value? What other means are available for the CEO to learn about the quality of care in their institution? In addition to quality, what other issues should be of primary concern? CONCLUSION: Quality care, as measured by outcomes and other means, is a necessary but not sufficient condition for success in the current environment. Market share is still largely determined on the basis of price. A basic commitment to quality is still paramount. The CEO also needs to focus on value, defined as quality/cost x efficacy (appropriateness) in dealing with constituent groups. Other components of success include developing a clear vision for the institution and finding appropriate partners. Public accountability presents a challenge and an opportunity for CEOs to demonstrate commitment to meeting the hospital's obligations.

Pharmacokinetics and pharmacodynamics of recombinant factor VIIa.

OBJECTIVE: To evaluate the pharmacokinetics and pharmacodynamics of recombinant activated factor VII (rFVIIa). METHODS: Single-dose pharmacokinetics of three dose levels (17.5, 35, and 70 micrograms/kg) of rFVIIa were investigated in 15 patients with hemophilia with severe factor VIII or factor IX deficiency (with or without inhibitors) while they were in the nonbleeding state and during bleeding episodes. Factor VII clotting activity (FVII:C) was determined 5 minutes before and at 10, 20, and 50 minutes and 2, 4, 6, 8, 12, and 24 hours after rFVIIa administration. Model-independent pharmacokinetic analysis of FVII:C plasma concentration-time data included determination of plasma clearance, mean residence time, and volume of distribution. rFVIIa recovery was determined from the plasma FVII:C observed 10 minutes after administration. Pharmacodynamic assessments of prothrombin time, activated partial thromboplastic time, and Factor X values obtained concurrently with FVII:C samples were performed. RESULTS: Sufficient data to allow pharmacokinetic parameter calculation were available for 25 nonbleeding episodes in 11 patients (17.5 micrograms/kg, n = 8; 35 micrograms/kg, n = 9; 70 micrograms/kg, n = 8) and for five bleeding episodes in three patients (17.5 micrograms/kg, n = 2; 35 micrograms/kg, n = 2; 35 micrograms/kg, n = 1). Recovery was calculated during 27 nonbleeding and 17 bleeding episodes. rFVIIa distribution volume is two to three times that of plasma. Median clearance was low--31.0 ml/hr.kg in nonbleeding episodes and 32.5 mg/hr.kg in bleeding episodes. In nonbleeding episodes, median mean residence time was 3.44 hours and median half-life was 2.89 hours. In bleeding episodes, the elimination rate appears to be higher, with a median mean residence time of 2.97 hours and a median half-life of 2.30 hours. Recovery was 45.6% during nonbleeding conditions and 43.5% during bleeding episodes (p = 0.0006); it was statistically lower with the highest dose level than with the 17.5 and 35 micrograms/kg doses (p = 0.007). A significant statistical relationship was observed between values of the prothrombin time and activated partial thromboplastin time, and values of FVII:C with use of maximum effect model. CONCLUSIONS: The pharmacokinetics of rFVIIa are linear in the dose range evaluated. The results suggest potential value of prothrombin time determination in the monitoring of rFVIIa therapy.

Safety and initial clinical efficacy of three dose levels of recombinant activated factor VII (rFVIIa): results of a phase I study.

The safety and efficacy of recombinant DNA-produced factor VIIa (rFVIIa) was investigated in 15 haemophilic patients in non-bleeding states and during bleeding episodes (mild to moderate joint bleed). Patients with severe haemophilia A without inhibitors (n = 4), haemophilia A with inhibitors (n = 10), and haemophilia B with inhibitor (n = 1) received one or more doses of rFVIIa during 32 non-bleeding study episodes and 23 bleeding episodes. The study was an open, uncontrolled, dose-escalation (17.5 micrograms/kg, 35 micrograms/kg, 70 micrograms/kg) trial. Physical evaluation, laboratory assessment, and immunology testing were conducted at baseline, monthly for 3 months and every 3 months thereafter. The immediate safety of rFVIIa was assessed by monitoring of D-dimer, fibrinogen, platelet count, antithrombin III, thrombin-antithrombin complex, and alpha 2-antiplasmin 5 min before and at multiple times throughout the following 24 h. Prothrombin time (PT) and activated partial thromboplastin time (aPTT) values were also obtained. Pain, swelling, joint circumference, and range of motion were recorded before administration of the initial dose of rFVIIa in bleeding patients and at 6, 12, and 24 h. Haemostatic response to rFVIIa was observed in patients with severe VIII and IX deficiency with and without inhibitors. Therapy with rFVIIa was judged effective in 19 of the 22 evaluable bleeding episodes at one or more time points. The 35 micrograms/kg and 70 micrograms/kg doses were associated with higher response rates at 6 and 12 h compared to the 17.5 micrograms/kg dose level. A second dose of rFVIIa was administered in 20 of the 22 bleeding episodes.(ABSTRACT TRUNCATED AT 250 WORDS)