Clinical and microbiological characteristics of Eggerthella lenta bacteremia.

Eggerthella lenta is an emerging pathogen that has been underrecognized due to historical difficulties with phenotypic identification. Until now, its pathogenicity, antimicrobial susceptibility profile, and optimal treatment have been poorly characterized. In this article, we report the largest cohort of patients with E. lenta bacteremia to date and describe in detail their clinical features, microbiologic characteristics, treatment, and outcomes. We identified 33 patients; the median age was 68 years, and there was no gender predominance. Twenty-seven patients (82%) had serious intra-abdominal pathology, often requiring a medical procedure. Of those who received antibiotics (28/33, 85%), the median duration of treatment was 21.5 days. Mortality from all causes was 6% at 7 days, 12% at 30 days, and 33% at 1 year. Of 26 isolates available for further testing, all were identified as E. lenta by both commercially available matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) systems, and none were found to harbor a vanA or vanB gene. Of 23 isolates which underwent susceptibility testing, all were susceptible to amoxicillin-clavulanate, cefoxitin, metronidazole, piperacillin-tazobactam, ertapenem, and meropenem, 91% were susceptible to clindamycin, 74% were susceptible to moxifloxacin, and 39% were susceptible to penicillin.

Rat bite fever as a presenting illness in a patient with AIDS.

The etiology of culture-negative septic arthritis is poorly characterised in persons infected with human immunodeficiency virus (HIV). New molecular methods may assist in the investigation of culture-negative infections of sterile sites, including septic arthritis. We describe the first case of septic arthritis due to the cause of rat bite fever (RBF), Streptobacillus moniliformis, confirmed by 16S rRNA sequence analysis, in a patient with newly diagnosed HIV infection.

Safety and efficacy of a maternal vaccine for the passive protection of broiler chicks against necrotic enteritis.

Necrotic enteritis is a potentially fatal multifactorial disease of chickens, which under commercial conditions is often associated with increased levels of mortality and reduced bird performance. The safety and efficacy of a Clostridium perfringens type A alpha-toxoid (Netvax™) formulated as an oil emulsion was investigated, following maternal immunization of broiler breeder hens, housed under commercial conditions, by the intramuscular route. A total of 11,234 hens were vaccinated across two integrated poultry sites. The vaccine was safe with no systemic reactions or adverse effects on bird performance detected. Vaccination resulted in a significant increase in anti-alpha toxin antibody in the hen that was maintained throughout the study, and subsequently transferred to their progeny throughout the laying period via egg yolk. Chicks hatched from eggs produced from vaccinated hens were shown to have reduced mortality specifically related to progeny flocks where gross gut lesions associated with necrotic enteritis were observed in control chicks. Further, whilst C. perfringens was isolated from control chicks with necrotic enteritis lesions, no such isolations were made at these time points from chicks from vaccinated hens. These results indicate that, under commercial conditions, maternal vaccination with Netvax™ can help to control losses related to necrotic enteritis.

Application of a bubble column for evaporative cooling and a simple procedure for determining the latent heat of vaporization of aqueous salt solutions.

In this work we have studied the evaporative cooling effect produced in a continuous flow air bubble column, containing water and salt solutions. We have established that, at equilibrium, a significant reduction in temperature is produced in an insulated, continuous flow, bubble column. For example, with a continuous flow of inlet air at 22 degrees C, a water bubble column cools to about 8 degrees C, at steady state equilibrium. The cooling effect observed in a continuous bubble column of concentrated aqueous salt solution could be used for commercial applications, such as for evaporative cooling systems. We have developed a simple method, based on the steady state thermal energy balance developed in a bubble column, to determine the latent heat of vaporization of the liquid in the column. Only the equilibrium temperature of the bubble column, the temperature of the inlet gas and the hydrostatic pressure across the column need to be measured. This analysis has been used to determine the heat of vaporization for water and some concentrated salt solutions.

Rheumatoid arthritis synovial T cells regulate transcription of several genes associated with antigen-induced anergy.

Rheumatoid arthritis (RA) is a chronic, inflammatory synovitis whose pathogenesis may involve autoimmune mechanisms. Anergy is a state of T-cell nonresponsiveness characterized by downregulated IL-2 production. Paradoxically, RA T cells are hyporesponsive and proliferate poorly to antigens and mitogens, thus sharing some characteristics with anergic T cells. We analyzed the molecular basis of anergy in cloned human CD4+ T cells using differential display RT-PCR and subsequently examined the levels of differentially expressed transcripts in RA and, as control, reactive arthritis (ReA) synovium. Several transcriptional events were common to anergic T cells and RA synovium. These included downregulation of CALMODULIN:, which is critical to T-cell activation, and of cellular apoptosis susceptibility protein, which may mediate resistance to apoptosis in RA. Transcription of CALMODULIN: in RA synovium was less than 1% of that in ReA and was lower in RA synovial fluid mononuclear cells than in paired PBMCs. Following anti-TNF-alpha therapy in vivo, RA PBMC CALMODULIN: transcripts increased five- to tenfold. Pharmacological calmodulin blockade in vitro impaired antigen-specific proliferation. These data provide a link between reduced CALMODULIN: transcription and impaired T-cell responsiveness in RA. The identification of transcriptional changes common to anergic and RA synovial T cells should help interpret some of the characteristic RA cellular defects.

The dispersion of natural oils in de-gassed water.

Recent studies have demonstrated that pure hydrocarbon oils can be dispersed in water as fine droplets without the use of additives. The high interfacial tension between hydrocarbons and water is expected to cause cavitation between oil droplets during separation. This cavitation is aided by dissolved atmospheric gases present in both the oil and water. Their removal allows oil droplets to be readily dispersed in water. In this paper we report on the effect of the de-gassing process on the dispersion of several natural, water immiscible oils. These natural, mixed oils are eucalyptus, lavender and tea tree oil. Although these oils are mixtures and in some cases not as hydrophobic as those used in the earlier studies, the effect of de-gassing substantially enhances their dispersion, producing micron-sized droplets without the need for additives. Dispersions of these natural oils in pure water have a wide range of uses where purity is an advantage, for example, in skin cleaning products and oral sprays.

The extraction of polymeric collagen from biopsies of human skin.

1. Medium sized biopsies (100 mm2) of human skin from 14 subjects yielded sufficient polymeric collagen for depolymerisation and ultrastructural investigations. 2. The yields obtained from one skin specimen by the alpha-amylase, EDTA and lyotropic relaxation (water) methods of extracting polymeric collagen are similar. 3. The responses to depolymerisation treatments of the three polymeric collagen samples extracted by each of the three methods from one skin specimen are cross-correlated. There are however electron microscopical differences between the three polymeric collagen samples. 4. The results show that it feasible to study the polymeric collagen of normal and diseased human skin from medium sized biopsies.

Transdermal nitroglycerin patch therapy reduces the extent of exercise-induced myocardial ischemia: results of a double-blind, placebo-controlled trial using quantitative thallium-201 tomography.

OBJECTIVES: This study prospectively evaluated whether transdermal nitroglycerin patches could limit the extent of exercise-induced left ventricular ischemia as assessed by quantitative thallium-201 tomography. BACKGROUND: Although antianginal medications are effective at reducing chest pain symptoms in patients with coronary artery disease, there is limited evidence that these agents can also reduce myocardial ischemia. METHODS: This was a randomized, double-blind, parallel, placebo-controlled trial evaluating nitroglycerin patch therapy in patients in stable condition with angiographic coronary artery disease and no previous myocardial infarction. All patients were weaned from antianginal agents and had a baseline symptom-limited treadmill test followed by thallium-201 tomography. Forty patients with perfusion defects involving > or = 5% of the left ventricle were randomized to receive either intermittent (12 h on/off) active nitroglycerin patch therapy (0.4 mg/h) or placebo. Exercise tomography was repeated a mean (+/- SD) of 6.1 +/- 1.8 days after randomization. RESULTS: Patients randomized to receive active patch therapy had a significant reduction in their total perfusion defect size (-8.9 +/- 11.1%) compared with placebo-treated patients (-1.8 +/- 6.1%, p = 0.04), which was most apparent in those with the largest (> or = 20%) baseline perfusion defects (-11.4 +/- 13.4% vs. 1.0 +/- 3.6%, respectively, p < 0.02). Furthermore, 7 (33%) of 21 patients receiving active therapy had a > or = 10% decrease in their perfusion defects compared with only 1 (5%) of 19 patients randomized to receive placebo (p = 0.002). Nitrate therapy did not significantly reduce heart rate, blood pressure or double product, indicating benefit through enhancement of coronary blood flow. CONCLUSIONS: Short-term, intermittent nitroglycerin patch therapy significantly reduces myocardial ischemia, particularly in patients with large ischemic perfusion defects. Thallium-201 tomography can be used to assess sequential changes in the extent of exercise-induced left ventricular ischemia.

Analysis of ambulatory electrocardiograms in 15 patients during spontaneous ventricular fibrillation with special reference to preceding arrhythmic events.

Fifteen patients sustained ventricular fibrillation during ambulatory electrocardiographic recording in a period of 3.5 years over which time 16,500 ambulatory electrocardiograms were analyzed (prevalence = 0.09% or 1/1,100). Eight patients died, and seven survived cardiopulmonary resuscitation. Quantitative analysis of hourly ventricular arrhythmias prior to ventricular fibrillation revealed an increased frequency of premature ventricular beats and ventricular tachycardia, especially in the 2 hours immediately before ventricular fibrillation. Ventricular fibrillation was initiated by ventricular tachycardia in all 15 cases. These runs of ventricular tachycardia were characterized by their unusual length (mean = 560 +/- 536 beats) and their rapid rate (241 +/- 45 beats/min). Although an R on T premature ventricular beat initiated ventricular tachycardia and ventricular fibrillation occasionally, the mean prematurity index of the initiating premature ventricular beat was not early (mean = 1.27 +/- 0.28). QT prolongation was present in only 3 of the 15 patients (mean QTc interval = 0.42 +/- 0.06). Left ventricular dysfunction (mean left ventricular ejection fraction = 34.9 +/- 9.9%) and coronary artery disease were nearly always present. The cardiac medications most frequently associated with these patients at the time of ventricular fibrillation were digitalis and quinidine.

De-gassed water is a better cleaning agent.

It is demonstrated that de-gassed water is more effective at dispersing hydrophobic "dirt", such as liquid hydrocarbons or oils. This effect appears to be due to the reduction of natural cavitation, which would otherwise oppose the dispersion of hydrophobic liquid droplets into water. De-gassing of the oil enhances this effect still further, and this has led to a proposal for a novel cleaning process, based on using a combination of a de-gassed (hydrophobic) solvent followed by rinsing in de-gassed water. This method might be useful as an effective, detergent-free cleaning process. Also reported are some initial studies which suggest that the effect of "inert" dissolved gases on the electrical conductivity of water may need to be reconsidered.

The use of a systemic prime/mucosal boost strategy with an equine influenza ISCOM vaccine to induce protective immunity in horses.

In horses, natural infection confers long lasting protective immunity characterised by mucosal IgA and humoral IgGa and IgGb responses. In order to investigate the potential of locally administered vaccine to induce a protective IgA response, responses generated by vaccination with an immunostimulating complex (ISCOM)-based vaccine for equine influenza (EQUIP F) containing A/eq/Newmarket/77 (H7N7), A/eq/Borlänge/91 (H3N8) and A/eq/Kentucky/98 (H3N8) using a systemic prime/mucosal boost strategy were studied. Seven ponies in the vaccine group received EQUIP F vaccine intranasally 6 weeks after an initial intramuscular immunisation. Following intranasal boosting a transient increase in virus-specific IgA was detected in nasal wash secretions. Aerosol challenge with the A/eq/Newmarket/1/93 reference strain 4 weeks after the intranasal booster resulted in clinical signs of infection and viral shedding in seven of seven influenza-naive control animals whereas the seven vaccinated ponies had statistically significantly reduced clinical signs and duration of virus excretion. Furthermore, following this challenge, significantly enhanced levels of virus-specific IgA were detected in the nasal washes from vaccinated ponies compared with the unvaccinated control animals. These data indicate that the intranasal administration of EQUIP F vaccine primes the mucosal system for an enhanced IgA response following exposure to live influenza virus.

Effect of vitamin A on bone resorption: evidence for direct stimulation of isolated chicken osteoclasts by retinol and retinoic acid.

The effects of retinol (vitamin A) and retinoic acid on primary cultures of isolated chicken osteoclasts have been studied. The experiments were performed to establish the direct actions of these two agents on the organization of cytoskeletal structures, on the acid phosphatase contents, and on the bone resorption activities of these cells. The results showed that by treating the cultures with retinol or retinoic acid, from 10(-8) to 10(-5) M, there were dose-related responses of the osteoclasts. Adhesion to the substratum was stimulated by increasing the number of cells exhibiting the specialized dot-like adhesion structures, or podosomes, which represent the active part of the sealing zone. The treatments also induced rearrangement of the microtubular patterns with reversible depolymerization of microtubules. Acid phosphatase activity was significantly higher both in vitamin A-treated osteoclasts and in their media. When [3H]proline-labeled bone particles were added to the retinoid-treated osteoclasts, the release of [3H]proline was increased significantly compared to controls. These results suggest that the two vitamin A metabolites cause several modifications of the metabolic status of isolated osteoclasts that result in augmented rates of bone resorption.

Osteoprogenitor cells of mature human skeletal muscle tissue: an in vitro study.

The presence of osteogenic progenitors in human skeletal muscle is suggested by the formation of ectopic bone in clinical and experimental conditions, but their direct identification has not yet been demonstrated. The aims of this study were to identify osteogenic progenitor cells in human skeletal muscle tissue and to expand and characterize them in culture. Specimens of gracilis and semitendinosus muscle were obtained from young adults and digested to separate the connective tissue and satellite cell fractions. The cells were cultured and characterized morphologically and immunohistochemically using antibodies known to be reactive with primitive osteoprogenitor cells, pericytes, intermediate filaments, and endothelial cells. Alkaline phosphatase activity and osteocalcin gene expression were also determined. In the early stages of culture, the connective tissue cells obtained were highly positive for primitive osteoprogenitor cell and for pericyte markers. Alkaline phosphatase activity was detectable at early stages of culture and rose as a function of time, whereas primitive osteoprogenitor cell markers declined and osteocalcin mRNA expression became detectable by reverse transcriptase-polymerase chain reaction (RT-PCR). It is shown that human skeletal muscle connective tissue contains osteogenic progenitor cells. Their identification as pericytes, perivascular cells with established osteogenic potential, suggests a cellular link between angiogenesis and bone formation in muscle tissue. These cells are easily cultured and expanded in vitro by standard techniques, providing an alternative source of osteogenic progenitor cells for possible cell-based therapeutic use in certain conditions.

Titration of allergenicity using a passive cutaneous anaphylaxis inhibition test.

A method for titrating allergenicity is described and validated by demonstrating that both baby hamster kidney cell lysate and hamster serum are capable of inhibiting the passive cutaneous anaphylaxis reactions produced by anti-BHK bovine serum in the skin of goats.

A pH-sensitive fluor, CypHer 5, used to monitor agonist-induced G protein-coupled receptor internalization in live cells.

G protein-coupled receptors (GPCRs) are the largest family of proteins involved in transmembrane signal transduction and are actively studied because of their suitability as therapeutic small-molecule drug targets. Agonist activation of GPCRs almost invariably results in the receptor being desensitized. One of the key events in receptor desensitization is the sequestration of the receptor from the cell surface into acidic intracellular endosomes. Therefore, a convenient, generic, and noninvasive monitor of this process is desirable. A novel, pH-sensitive, red-excited fluorescent dye, CypHer 5, was synthesized. This dye is non-fluorescent at neutral pH and is fluorescent at acidic pH. Anti-epitope antibodies labeled with this dye were internalized in an agonist concentration- and time-dependent manner, following binding on live cells to a range of GPCRs that had been modified to incorporate the epitope tags in their extracellular N-terminal domain. This resulted in a large signal increase over background. When protonated, the red fluorescence of CypHer 5 provides a generic reagent suitable for monitoring the internalization of GPCRs into acidic vesicles. This approach should be amenable to the study of many other classes of cell surface receptors that also internalize following stimulation.

Antiarrhythmic and hemodynamic evaluation of indecainide and procainamide in nonsustained ventricular tachycardia.

The present trial was a placebo-controlled, randomized, parallel study comparing indecainide to procainamide. A 24-hour intravenous phase measured and compared invasive hemodynamics, followed by oral administration for assessment of arrhythmia suppression. Thirty-two patients (mean age 61 years) with asymptomatic or mildly symptomatic nonsustained ventricular tachycardia (VT) were evaluated, 15 while receiving indecainide and 17 while receiving procainamide. A total of 8 patients had serious toxicity during the intravenous phase; 6 receiving indecainide experienced increased left ventricular dysfunction or worsening arrhythmia (sustained VT, arrhythmic death) while 2 receiving procainamide developed serious hypotension. Proarrhythmia developed in 3 of 15 (20%) of the indecainide patients, but in no procainamide patient. In those tolerating indecainide, long-term suppression of ventricular premature complexes (VPCs) and of runs of VT was more consistent than with procainamide. While indecainide was a potent suppressor of spontaneous VPCs and VT, patients with significant left ventricular dysfunction could not tolerate it. The indecainide patients developing serious toxicity had a common hemodynamic profile: ejection fraction less than 25%, elevated left ventricular filling pressures, low cardiac and stroke volume index and minimal cardiac reserve. Indecainide has a poor risk-benefit ratio in patients similar to the current population, who have potentially lethal ventricular arrhythmias and severe left ventricular dysfunction.

Analysis of the spontaneous variability of ventricular arrhythmias: consecutive ambulatory electrocardiographic recordings of ventricular tachycardia.

Results are reported of analysis of the variability of complex ventricular arrhythmias in a cohort of 110 patients selected for the presence of ventricular tachycardia (VT). All patients were enrolled in investigational antiarrhythmic drug trials and had an average of 4 consecutive days of placebo ambulatory electrocardiographic recording to serve as the database for this study. Using a statistical approach incorporating analysis of variance, the minimum percent reductions of ventricular premature complexes, couplets and VT were calculated to establish "drug effect" rather than variability at a significance level of 0.05. The relative variability of ventricular arrhythmias in prognostically important groups was also analyzed: (1) coronary artery disease (CAD) (n = 57) vs no CAD (n = 53); (2) patients with a left ventricular ejection fraction of 40% or less (n = 52) vs those with an ejection fraction greater than 40% (n = 58); and (3) patients with frequent runs of VT (10 or more runs/day, n = 63) vs infrequent VT (n = 47). Multiple regression analysis revealed that patients with CAD have significantly greater premature ventricular complex variability than patients without CAD (p less than 0.01). Also, patients with frequent VT runs have greater VT variability than that previously reported in smaller studies, thus requiring greater VT reductions to establish drug effect. Whether the variability of ventricular arrhythmia is itself an independent risk factor for sudden cardiac death is unknown.

Exploring the minimal dose of amiodarone with antiarrhythmic and hemodynamic activity.

Amiodarone in doses of 200 to 400 mg/day has shown promise in secondary prevention trials for reducing mortality in patients surviving myocardial infarction who have complex ventricular ectopy or nonsustained ventricular tachycardia, or both. In an attempt to explore the lowest dose of amiodarone with antiarrhythmic and hemodynamic activity, we studied 48 patients (mean age 53 +/- 11 years, ejection fraction 23 +/- 9%, clinical heart failure in 85%) with nonsustained ventricular tachycardia. This was a 3-month, randomized, parallel, double-blind pilot study comparing placebo (n = 16) with amiodarone 50 mg/day (n = 15) and 100 mg/day (n = 17). Patients randomized to amiodarone received a mean loading dose of 422 mg/day for the first study week. At the end of the 12 weeks, amiodarone (100 mg) significantly reduced ventricular premature complexes (177 +/- 64 to 98 +/- 38/hour), couplets (8 +/- 3 to 4 +/- 2/hour), and runs of nonsustained ventricular tachycardia (13 +/- 7 to 3 +/- 2/day), all p < 0.01 versus baseline. In addition, 10 of 14 patients taking 100 mg/day had total suppression of nonsustained ventricular tachycardia compared with 4 of 15 taking placebo, p = 0.021. Left ventricular ejection fraction improved by > or = 7% (absolute) in 11 of 29 patients taking amiodarone as compared with only 1 of 15 placebo patients (p = 0.02). In these 11 patients with the greatest measurable hemodynamic improvement, amiodarone significantly increased ejection fraction (21 +/- 7% to 33 +/- 11%, p < 0.01), stroke volume index (28 +/- 9 to 40 +/- 7 ml/m2, p < 0.01) and decreased end-systolic volume index (116 +/- 48 to 92 +/- 44 ml/m2, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Discontinuation of chronic diuretic therapy in stable congestive heart failure secondary to coronary artery disease or to idiopathic dilated cardiomyopathy.

To assess the feasibility of diuretic discontinuation in patients with stable congestive heart failure (CHF) and to identify risk factors for subsequent development of congestion, a prospective, 12-week clinical trial of unmasked diuretic withdrawal was conducted with continuation of background CHF therapy and double-blind randomization to placebo or lisinopril. Forty-one patients with a history of CHF and continuous diuretic use for > or = 3 months had all diuretic therapy discontinued, and therapy with lisinopril 5 mg (target 20 mg)/day (n = 20) or placebo (n = 21) begun the next day. A diuretic was restarted if new or worsening CHF symptoms and signs developed. Twelve patients (29%) did not require diuretic reinitiation at any time during follow-up, whereas 29 (71%) restarted diuretic therapy after a median of 15 days (range 2 to 42). Fourteen patients taking lisinopril and 15 taking placebo required diuretic drugs (p = NS). The baseline daily furosemide dose of > 40 mg, a left ventricular ejection fraction < or = 0.27, and history of systemic hypertension were independently predictive of early diuretic reinitiation by Cox proportional-hazards analysis. The probability of remaining diuretic-free after 6 weeks was 71% if none of these criteria were present. This trial demonstrates the feasibility of discontinuing diuretic drugs in certain patients with stable CHF and predicts those patients likely to require reinitiation of therapy. Diuretic withdrawal may be warranted when the furosemide dose is < or = 40 mg/day, left ventricular ejection fraction is > 0.27 and when no history of systemic hypertension is present.

An assay for plasma somatomedin: [3H]thymidine incorporation by isolated rabbit chondrocytes.

The incorporation of [3H]thymidine by rabbit chondrocytes in vitro has been developed as a sensitive assay for plasma somatomedin. A concentration of normal plasma of 2-5% enhanced [3H]thymidine incorporation by 5- to 20-fold compared with basal levels in the absence of plasma. The mean potency of plasma from normal adult men was 0-96+/-0-1 u./ml (mean+/-S.D.) and from acromegalic patients 1-9+/-0-4 u./ml. The apparent potency of hypopituitary plasma alone increased on heating which suggested the presence of heat-labile inhibitors of somatomedin activity. The potency of heated hypopituitary plasma (0-6+/-0-09 u./ml) remained significantly lower (P less than 0-01) than normal plasma. Human growth hormone (0-1-20 muu./ml), bovine growth hormone (0-5 20 muu./ml), insulin (0-5-5 muu./ml) and glucose (0-3-2 mmol/1) had no direct effect on the incorporation of [3H]thymidine. Chondrocytes which had been previously stored frozen also showed a response to plasma somatomedin.