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Background: Pump thrombosis (PT) and related adverse complications contributed to the HeartWare Ventricular Assist Device (HVAD) market withdrawal. Many patients still receive lifelong support, with deficient PT surveillance based on pump power trends. Analysis of pump vibrations is better for detecting PT. Here, we investigated the feasibility of an extracorporeal accelerometer to detect PT from pump vibrations propagated out on the driveline., Methods: In a porcine HVAD model (n = 6), an accelerometer was attached to the pump as a reference and another to the driveline for comparisons of signals. In total, 59 thrombi were injected into the heart to induce PT, followed by intermittent thrombus washout maneuvers. Signals were compared visually in spectrograms and quantitatively in third harmonic saliences (S 3H ) by correlation analysis. Receiver operating characteristic curves expressed the method's outcome in sensitivity vs specificity, with the overall diagnostic performance in the area under the curve (AUC) score., Results: Five experiments had good driveline signal strength, with clear spectrographic relationships between the 2 accelerometers. Third harmonic driveline vibrations were visible 20 vs 30 times in the reference. The comparison in S 3H showed a strong correlation and yielded an AUC of 0.85. Notably, S 3H proved robust regarding noise and false PT detections., Conclusions: An extracorporeal accelerometer on the driveline can be a readily available method for accurate HVAD PT detection before an accelerometer integration with left ventricular assist device is feasible., (Copyright © 2023 International Society for the Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

We report Taenia ovis infection in Danish sheep for the first time. In spring 2016, the metacestode stage of T. ovis was at slaughter observed in heart muscles, diaphragm and skeletal muscles from approx. a third of all sheep from one specific farm localised in South Jutland. The diagnosis was confirmed by molecular typing of the mitochondrial cytochrome c oxidase I (cox1) gene. Three newly imported dogs were suspected but the definitive host was unidentifiable. The finding is not regulated in the meat control procedures. However, infected meat is usually condemned due to aesthetic reasons causing economic losses. Thus, finding of T. ovis is of concern to sheep meat producers in the area, as the infection could have spread further on to other farms., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Halicephalobus gingivalis is an opportunistic parasite which is known to cause fatal meningoencephalomyelitis primarily in equines but sporadically also in humans. In April 2014, laboratory examination of the head of a young dairy calf, euthanized due to severe central nervous system symptoms, revealed the presence of granulomatous to necrotizing encephalitis and myriads of nematodes in the brain lesion. Morphologically the parasites were identified as H. gingivalis. The diagnosis was confirmed by molecular analysis of the large subunit (LSU) rRNA and the small subunit (SSU) rRNA genes, revealing genetic variations of 0.5-4.4% and 0.7-8.6%, respectively, between the H. gingivalis isolated from the Danish calf and published isolates, collected worldwide from free-living and parasitic stages of the nematode. Clinical symptoms and histological changes indicated infection with H. gingivalis from another three calves in the herd. This is the first scientific publication of H. gingivalis induced meningoencephalomyelitis in ruminants. As ante mortem diagnosis is a major challenge, the infection may easily remain undiagnosed in cattle., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Spirocerca lupi causes formation of nodules that may transform into sarcoma in the walls of aorta, esophagus and stomach of infected canids. In February 2013, post mortem examination of a red fox (Vulpes vulpes) hunted in Denmark revealed the presence of several nodules containing adult worms of Spirocerca sp. in the stomach and the omentum. The nodules largely consisted of fibrous tissue with infiltration of mononuclear cells, neutrophilic granulocytes and macrophages with hemosiderin deposition. Parasitological examination by three copromicroscopic methods, sedimentation, flotation with saturated sugar-salt solution, and sieving failed to detect eggs of Spirocerca sp. in feces collected from the colon. This is the first report of spirocercosis in Denmark, and may have been caused by a recent introduction by migrating paratenic or definitive host. Analysis of two overlapping partial sequences of the cox1 gene, from individual worms, revealed distinct genetic variation (7-9%) between the Danish worms and isolates of S. lupi from Europe, Asia and Africa. This was confirmed by phylogenetic analysis that clearly separated the Danish worms from other isolates of S. lupi. The distinct genetic differences of the current worms compared to other isolates of S. lupi may suggest the presence of a cryptic species within Spirocerca., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Preoperative cardiac risks and clinical indications for vascular surgery are both important determinants of outcome following a vascular operation. Using the nonrandomized cohort from the Coronary Artery Revascularization Prophylaxis (CARP) Trial, we analyzed the predictors of outcome based on the presenting vascular problem and prevalence of comorbid conditions and cardiac risks., Methods and Results: Between March 1, 1999 and February 28, 2003, 4414 patients were ineligible for randomization in the CARP Trial and their survival was retrieved through the BIRLS system (the Department of Veterans Affairs Beneficiary Identification and Records Locator Subsystem). Surgical indications were either an abdominal aortic aneurysm (N = 1598) or lower extremity ischemia for claudication (N = 1116), rest pain (N = 670), or tissue loss (N = 1030). Patients were screened for major cardiac risks that included a history of angina, congestive heart failure, myocardial infarction, ventricular arrhythmias, pathological q-waves, and diabetes. The absence of multiple cardiac risks, as the sole reason for exclusion from randomization, occurred in 2314 (52.4%) screened patients and their probability of survival at 2.5-year post-surgery was 0.88. This was better than the survival of the remaining excluded patients (N = 2100), which was 0.75 (P < .0001) and the randomized cohort (N = 462), which was 0.80 (P < .0001). By Cox regression analysis, urgent surgery, congestive heart failure, ventricular arrhythmias and creatinine >3.5 mg/dL were significantly associated with long-term postoperative mortality., Conclusions: Patients without multiple cardiac risks or comorbid conditions have a good outcome following elective vascular surgery. Urgent surgery, creatinine >3.5 mg/dL, congestive heart failure, and ventricular arrhythmias are identifiers of a poor long-term outcome and may justify aggressive strategies for risk-stratification in the postoperative period.

Atrazine (ATR), 2-chloro-4-ethylamino-6-isopropylamino-s-triazine, has been implicated in numerous studies to act as an endocrine disruptor, specifically by altering estradiol signaling via increased aromatase activity. Fluorescence polarization (FP) was used to show that the binding equilibria between estrogen receptor-alpha or estrogen receptor-beta, and estradiol were not affected by ATR and its metabolites: ATR-desethyl (ADE), ATR-desisopropyl (ADI), ATR-desethyldesisopropyl (ADD) and terbuthylazine (TBZ). Therefore, ATR and its degradation products were studied to determine their ability to inhibit phosphodiesterase (PDE), the enzyme responsible for hydrolyzing the second messenger cAMP to 5'-AMP. Using FP, it was found that ATR inhibited PDE with an IC50 value of 1.8 microM. This was lower than the known PDE inhibitor isobutyl methylxanthine (IBMX), which had an IC50 value of 4.6 microM. The ATR degradation products ADE, ADI, ADD and TBZ were less effective than ATR at inhibiting PDE when assayed using FP. Classical competitive binding assays, using radiolabeled 14C-cAMP in conjunction with thin layer chromatography (TLC), were used to determine that ATR was a competitive inhibitor of PDE with an association constant of 85 microM.

Pediatric asthma remains an important public health concern as its prevalence and cost to the health care system is rising. In order to promote innovative research in asthma therapies, the National Heart, Lung and Blood Institute created the Childhood Asthma Research and Education Network in 1999. As its first study, the steering committee of the Childhood Asthma Research and Education Network designed a randomized clinical trial to determine if persistent asthma could be prevented in children at a high risk to develop the disease. This communication presents the design of its first clinical trial, the Prevention of Asthma in Kids (PEAK) trial and the organization of the Childhood Asthma Research and Education Network that developed and implemented this trial. Studies of the natural history of asthma have shown that, in persistent asthma, the initial asthma-like symptoms and loss of lung function occur predominately during the first years of life. Therefore, in the Prevention of Asthma in Kids study, children 2 and 3 years old with a positive asthma predictive index were randomized to twice daily treatment with fluticasone 88 microg or placebo via metered-dose inhaler and Aerochamber for 2 years. The double blind treatment period was followed by a 1-year observational period. Lung function was measured by spirometry and oscillometry technique at 4-month intervals throughout the study. Bronchodilator reversibility and exhaled nitric oxide (ENO) studies were performed at the end of the treatment and observation periods. The primary outcome measure was the number of asthma-free days. Other secondary outcomes included number of exacerbations, use of asthma medications and lung function. These measures were chosen to reflect the progression of the disease from intermittent wheezing to persistent asthma and measurement of the extent of airflow limitation and airway reactivity.

Covalently linking 1-amino-3,7,8-trichlorodibenzo-p-dioxin with either keyhole limpet hemocyanin (KLH) or bovine serum albumin (BSA) provided antigens that generated antibodies in chickens. Competitive ELISA analysis demonstrated that the antibodies isolated from egg yolk (IgY) bound with 1,3,7,8-tetrachlorodibenzo-p-dioxin (1,3,7,8-TCDD). The antibodies were linked to CNBr-Sepharose to generate an immunoaffinity column. Radiolabeled 1,3,7,8-TCDD in a 0.05% Tween 20 solution was retained by the column and could be eluted by increasing the Tween 20 concentration. The binding efficiency for 10.7 ng per ml gel matrix ranged from 85 to 97%. Immunoaffinity columns generated by this method did not effectively bind 14C-1,3,7,8-TCDD from serum samples. Diluting the serum 1:20 with 0.05% Tween 20 increased the binding efficiency. Alternately, ethanol-hexane extraction followed by solid phase extraction on a carbon column using a fat removal protocol also provided an appropriate preaffinity column cleanup for serum samples. After this preaffinity column cleanup, spiked serum samples applied to the immunoaffinity column showed binding efficiencies of over 90%.

Interleukin-12 (IL-12) is a key regulator of cell-mediated immunity that has therapeutic potential in cancer and infectious disease. In a previous Phase 1 dose escalation study of a single test dose of recombinant human IL-12 (rhIL-12) followed 14 days later by cycles of five consecutive daily intravenous injections every 3 weeks, we showed that a dose level up to 500 ng/kg could be administered with acceptable levels of safety. Based on these results, a Phase 2 study was conducted. In the Phase 2 study, however, administration of rhIL-12 at this same dose level resulted in severe toxicities with some patients unable to tolerate more than two successive doses. Of the 17 patients receiving rhIL-12 in the Phase 2 study, 12 patients were hospitalized and two patients died. A thorough scientific investigation to determine the cause of this unexpected toxicity failed to identify any difference in the drug products used or the patient populations enrolled in the Phase 1 and Phase 2 studies that could have accounted for the profound difference in toxicity. The focus of the investigation therefore shifted to the schedule of rhIL-12 administration. We determined that a single injection of rhIL-12 2 weeks before consecutive dosing included in the Phase 1 study, but not in the schedule of administration in the Phase 2 study, has a profound abrogating effect on IL-12-induced interferon-gamma (IFN-gamma) production and toxicity. This observation of schedule-dependent toxicity of IL-12 has been verified in mice, as well as nonhuman primates. In this regard, a single injection of IL-12 before consecutive daily dosing protected mice and cynomolgus monkeys from acute toxicity including mortality and was associated with an attenuated IFN-gamma response. Because of this unique biologic response, careful attention to the schedule of administration is required to assure safe and effective clinical development of this highly promising cytokine.

Laboratory mice were inoculated with a nalidixic acid and novobiocin-resistant strain of Salmonella typhimurium. Contaminated fecal pellets were harvested 2 days postinoculation. Each half of a fecal pellet was found to contain equal numbers of Salmonella on a per weight basis. When separate halves were placed into a poultry feed, either treated or untreated, with an organic acid mixture (SAL CURB), the treatment was able to significantly (P < .001) reduce Salmonella contamination of the feed by almost two log orders per gram when compared with the untreated control.

Tissue-type plasminogen activator produced by recombinant DNA technology, has been established as an important thrombolytic agent in the treatment of acute myocardial infarction. New approaches to increase the effectiveness of this agent, including rapid high dose administration are being investigated. Several novel protein engineered variant forms of plasminogen activators have been produced that have increased thrombolytic potency in animal models and offer the potential of a more effective lower dose agent than can be administered clinically as a single bolus intravenous injection.

When a 100,000 x g supernatant from rat intestinal mucosa was incubated with 4,4'-bis([3H]methylsulfonyl)-2,2',5,5'-tetrachlorobiphenyl, [(CT3SO2)2TCB] a (CT3SO2)2TCB-protein complex was formed. The (CT3SO2)2TCB-protein complex was isolated and purified using gel filtration and ion-exchange chromatography. The protein portion of this complex was characterized to be liver fatty acid binding protein (L-FABP) by SDS-polyacrylamide gel electrophoresis and immunoblot analysis. No cross reactivity was observed in the immunoblot analysis between the purified protein and anti-heart or anti-intestinal fatty acid binding protein. (CT3SO2)2TCB was extractable from L-FABP and therefore not covalently bound to L-FABP.

In an attempt to ascertain the value of mediastinoscopy in peripheral lung lesions, records of 157 patients undergoing cervicomediastinal exploration (CME) at Wilford Hall USAF Medical Center were reviewed. Among patients with benign lesions, CME was positive in 90.6% of those who had central lesions and 58.3% of those with peripheral lesions. It was positive in all 7 patients who had peripheral lesions with associated mediastinal nodes on roentgenogram and negative in all 5 who had peripheral lesions without nodes. In the patients with malignant lesions, CME was positive in 72.9% of those who had central lesions and 58.1% of those with peripheral lesions. It was positive in 24 of 27 patients who had peripheral lesions with associated mediastinal nodes and negative in 15 of 16 patients with peripheral lesions without nodes. Although we recognize this to be a selected series, CME does appear to be valuable in patients with central lesions and peripheral lesions with mediastinal nodal involvement on roentgenogram. It does not appear to be as useful in those with peripheral lesions who do not have central nodal involvement.

Earlier studies have shown that C5 fragments induce an inflammatory reaction when instilled into the rabbit lung. Because C5a is rapidly converted to C5a des Arg in vivo, experiments were performed to determine which fragment was most effective in producing pulmonary inflammation in this animal model. C5a des Arg consistently produced marked inflammation. This was characterized by neutrophil accumulation, edema, hemorrhage, fibrin formation, and damage to alveolar epithelium. The time course of the inflammatory reaction initiated by C5a des Arg showed pulmonary vascular sequestration of neutrophils with no intra-alveolar migration at 30 minutes after injection. By 2 hours, interstitial and alveolar neutrophils were numerous, with the accumulation of neutrophils in the alveoli increasing to a maximum at 6 hours. At 24 and 48 hours, the predominant cells were mononuclear (macrophages). By 120 hours, the lesions were resolving. In contrast, at all doses examined, a similar instillation of C5a induced either no inflammation or a milder, more focal response than C5a des Arg. This inability of C5a to initiate inflammation was not apparently due to the generation of inhibitors, since mixtures of C5a and C5a des Arg were phlogistic. A prolonged, intrapulmonary infusion of C5a (20 minutes), in contrast to a bolus instillation (1 minute), did initiate an inflammatory response, which may reflect the conversion of the C5a to C5a des Arg in the lung. This study points out the inflammatory potential of products of complement activation, particularly of the C5 fragment C5a des Arg, when applied to the airway side of the lungs. This inflammatory response raises the possibility that cleavage of intrapulmonary C5 may play an important role in the initiation of pulmonary inflammation.

Mechanisms of neutrophil infiltration into the rabbit alveolus have been investigated. Complement activation in the circulation induced pulmonary vascular margination but not a significant level of alveolar infiltration. Instillation of C5 fragments into the airways, however, attracted neutrophils into the alveolar airspaces. The anaphylatoxin-inactive fragment of C5, C5a des Arg, was found to be much more active in this regard than C5a. Furthermore, these fragments were shown to induce the production of a neutrophil-directed chemoctactic factor from pulmonary macrophages, raising the question of whether the C5a des Arg was acting directly to attract neutrophils or indirectly via the macrophage. To substantiate a possible role for C5 and C5 fragments in alveolitis, active C5 was demonstrated in lavage fluids, and macrophage-derived C5 cleaving enzymes have been described. Finally, a route of neutrophil infiltration via migration through the alveolar capillary wall into the interstitium is proposed, and subsequent penetration of the alveolar epithelium out into the airspace. (Am J Pathol 97:93--110, 1979).

Leukotriene E4 was incubated with cysteine-conjugate beta-lyase isolated from the intestinal bacterium Eubacterium limosum. The reaction was terminated by addition of iodoacetic acid or dimethyl sulfate, and the products formed were isolated by reverse-phase high-performance liquid chromatography. The structures of two adducts of a metabolite were determined by uv spectroscopy, by gas-liquid radiochromatography, and by comparisons with chemically synthesized reference compounds. They were 5-hydroxy-6-S-carboxymethylthio-7,9-trans-11,14-cis-eicosatetraeno ic acid (iodoacetic acid adduct) and 5-hydroxy-6-S-methylthio-7,9-trans-11,14-cis-eicosatetraenoic acid (dimethyl sulfate adduct) indicating that the structure of the underivatized metabolite was 5-hydroxy-6-mercapto-7,9,11,14-eicosatetraenoic acid (5,6-HMETE). The latter product is formed by beta-lyase-catalyzed cleavage of the cysteine C-S bond in leukotriene E4. Leukotriene E4 was also metabolized to 5,6-HMETE by rat cecal contents. A product formed was trapped as the iodoacetic acid derivative and identified as 5-hydroxy-6-S-carboxy-methylthio-7,9,11,14-eicosatetraenoic acid. It is concluded that intestinal leukotriene E4, originating from biliary excretion of systemic cysteinyl leukotrienes or produced in the intestine, is converted by microfloral cysteine-conjugate beta-lyase to 5,6-HMETE.

Human tissue-type plasminogen activator (t-PA) is a glycoprotein used currently in thrombolytic therapy. Because of its rapid half-life (T1/2) of approximately five minutes, intravenous (IV) infusion of large doses (approximately 100 mg) are required in patients treated for myocardial infarction. To identify the determinant(s) on t-PA responsible for such rapid clearance, metabolically labeled forms of recombinant t-PA were analyzed in rats following IV administration. The following seven forms of t-PA were tested: (a) natural or glycosylated wild-type t-PA; (b) nonglycosylated wild-type t-PA; (c) delta F t-PA, which lacks the fibronectin fingerlike domain; (d) delta E t-PA, which lacks the epidermal growth factor (EGF) domain; (e) delta FE t-PA, which lacks both the finger and EGF domains; (f) delta FE3X t-PA, a form of delta FE t-PA in which Asn-linked glycosylation is prevented at all known glycosylation sites (Asn-117, 184, and 448; replaced by Gln); and (f) delta FE1X t-PA, a form of delta FE t-PA in which high-mannose-type glycosylation is prevented at Asn-117. Both glycosylated and nonglycosylated wild-type t-PA cleared in an exponential biphasic manner, with an initial alpha-phase T1/2 of 0.8 and 1.9 minutes, respectively. This result demonstrates that carbohydrate is not the primary mediator of the rapid clearance of t-PA. The liver was the primary organ responsible for uptake of these molecules. All other proteins tested, except for delta E t-PA, demonstrated primarily monophasic clearance patterns with T1/2 ranging between 12 and 27 minutes, and reduced uptake in the liver. delta E t-PA however, cleared in a biphasic manner with an alpha-phase T1/2 of 2.1 minutes. Results presented suggest that the clearance of t-PA is mediated by two distinct mechanisms. The primary determinant(s) responsible for modulating the rapid clearance of t-PA appears to be resident within the polypeptide sequence encoding the finger and/or EGF domains, with emphasis on the finger domain. A second and less significant contribution to clearance is defined by the presence and type of glycosylation.

Seventy-two patients with Starr-Edwards aortic prostheses of the 2300 series were followed for 1 to 73 months (average, 22 months) without receiving anticoagulants. Nine patients had clinical evidence of an embolic episode (12.5%). One of these patients died, and 5 were left with a significant residual neurological deficit. Two other patients had hemiparesis but recovered fully. Only 1 episode could be considered minor. The reported lower incidence of thromboembolism in patients receiving this prosthesis with adequate anticoagulation has now led us to reverse our previous position and recommend anticoagulation for patients receiving Starr-Edwards aortic prostheses.

The following mutants of human tissue-type plasminogen activator (t-PA) were constructed by deletion mutagenesis of t-PA cDNA, expressed in Chinese hamster ovary cells and purified to homogeneity: (a) t-PA-delta FE:t-PA lacking both the fibronectin fingerlike (F) domain and the epidermal growth factor (E) domain, (b) t-PA-delta FE1X:t-PA-delta FE with the glycosylated 117Asn mutagenized to Gln, and (c) t-PA-delta FE3X:t-PA-delta FE with the three known glycosylated Asn residues replaced by Gln. The mutant and natural t-PA (Mel-t-PA obtained from melanoma cell culture) were infused intravenously for four hours into rabbits with jugular vein thrombosis at doses ranging between 0.12 and 0.75 mg/kg. Fifty percent thrombolysis, determined by interpolation, was obtained with 0.4 mg/kg Mel-t-PA, 0.37 mg/kg t-PA-delta FE, 0.2 mg/kg t-PA-delta FE1X, and 0.40 mg/kg t-PA-delta FE3X. These infusion rates resulted in plateau levels of t-PA antigen in plasma of 0.055, 2.1, 0.6, and 0.5 micrograms/mL, respectively. At 50% lysis, the residual fibrinogen 30 minutes after the end of the infusion was 100%, 81%, 100% and 85% of baseline, and the residual alpha 2-antiplasmin was 82%, 55%, 85%, and 90%, respectively. These results indicate that t-PA-delta FE1X and t-PA-delta FE3X have a specific thrombolytic activity and fibrin specificity comparable to that of Mel-t-PA. t-PA-delta FE has a comparable specific thrombolytic activity but a lower fibrin specificity than Mel-t-PA. After the end of the infusion, t-PA-related antigen disappeared from plasma with an initial t1/2 of four minutes for Mel-t-PA, 25 minutes for t-PA-delta FE, 42 minutes for t-PA-delta FE1X, and 14 minutes for t-PA-delta FE3X. It is concluded that t-PA can be modified by deletion mutagenesis to yield variants with a markedly longer half-life in the blood. Some of these variants have a specific thrombolytic activity and fibrin specificity similar to that of natural t-PA. These variants may be useful to identify the structures in t-PA responsible for its clearance, specific thrombolytic activity, and fibrin specificity in vivo.