Susceptibility of multiresistant strains of Burkholderia cepacia to honey.

Twenty strains of Burkholderia cepacia, isolated principally from the sputum of cystic fibrosis patients, were tested for their susceptibility to eight antibiotics with a modified Kirby-Bauer Disc diffusion technique. All strains exhibited multiple but not identical patterns of antibiotic resistance. The sensitivity of all strains to honey was assessed with an agar dilution method.

Prediction of the mechanisms of enzyme-catalysed reactions using hybrid quantum mechanical/molecular mechanical methods.

The use of hybrid methods, involving both quantum mechanics and molecular mechanics, to model the mechanism of enzyme-catalysed reactions, is discussed. Two alternative approaches to treating the electrostatic interactions between the quantum mechanical and molecular mechanical regions are studied, involving either the inclusion of this term in the electronic Hamiltonian (QM/MM), or evaluating it purely classically (MO + MM). In the latter scheme, possible problems of using force fields that are standard for macromolecular modelling are identified.

Acidophiles in bioreactor mineral processing.

Mineral processing in bioreactors has become established in several countries during the past decade with industrial application of iron- and sulfur-oxidizing bacteria to release occluded gold from mineral sulfides. Cobalt extraction in bioreactors has also been commercialized, and development of high-temperature biooxidation of copper sulfides has reached pilot-plant scale. A variety of potentially useful mineral sulfide-oxidizing thermophiles have been recognized, but the most active strains have not been fully characterized.

Multiple chromosomes in Burkholderia cepacia and B. gladioli and their distribution in clinical and environmental strains of B. cepacia.

Burkholderia cepacia is found in soils and waters, it can be used in biocontrol and bioremediation but is also a human pathogen. It is not yet clear what differentiates pathogenic from non-pathogenic strains of the organism. In this study the multiple replicon structure was investigated in 28 strains of B.

Methods for animal satellite cell culture under a variety of conditions.

Primary and clonal culture systems have been devised and refined for animal-derived satellite cells. Satellite cell (SC) culture development includes efficient cell isolation techniques, establishment of effective plating and growth conditions, formulation of media requirements and thorough evaluation of experimental limitations. As the field of muscle cell culture has expanded, the number of animal species from which satellite cells have been isolated has increased.

Carboxylase genes of Sulfolobus metallicus.

Carbon dioxide limitation of Sulfolobus metallicus resulted in increased cellular concentrations of polypeptides that were predicted to be biotin carboxylase and biotin carboxyl-carrier-protein components of a protein complex. These polypeptides were coeluted from a native polyacrylamide gel and were estimated at 19 and 59 kDa after separation by denaturing gel electrophoresis. Their encoding genes were identified, sequenced and shown to code for polypeptides of 18,580 and 58,235 Da with similarities to biotin carboxyl carrier proteins and biotin carboxylases, respectively.

Successful use of cyclosporine in a lung transplant recipient with tacrolimus-associated hemolytic uremic syndrome.

Hemolytic-uremic syndrome (HUS) is a rare, but well-described complication in organ transplant recipients maintained on cyclosporine immunosuppression. Tacrolimus is a newer agent with similar immunosuppressant efficacy. In cases of cyclosporine-related HUS in renal transplant recipients, tacrolimus has been used successfully without recurrence of HUS.

Genotypic and phenotypic relationships in Burkholderia cepacia isolated from cystic fibrosis patients and the environment.

Twenty-one strains of Burkholderia cepacia isolated from the environment, and 21 clinical strains isolated principally from sputum of cystic fibrosis (CF) patients, were characterized genotypically by macrorestriction analysis (genome fingerprinting) and PCR ribotyping, and phenotypically by susceptibility to antibiotics and the ability to macerate onion tissue. The plasmid content of the strains was also investigated. Environmental isolates showed a high degree of genetic variability, all strains differing from both one another and the CF isolates.

Effects of interventions in health care settings on physical activity or cardiorespiratory fitness.

Introduction: This paper reviews studies of physical activity interventions in health care settings to determine effects on physical activity and/or fitness and characteristics of successful interventions.

Methods: Studies testing interventions to promote physical activity in health care settings for primary prevention (patients without disease) and secondary prevention (patients with cardiovascular disease [CVD]) were identified by computerized search methods and reference lists of reviews and articles. Inclusion criteria included assignment to intervention and control groups, physical activity or cardiorespiratory fitness outcome measures, and, for the secondary prevention studies, measurement 12 or more months after randomization.

Serologic responses to hepatitis C virus in solid organ transplant recipients.

Background: Hepatitis C (HCV) infection is known to have been transmitted by both blood transfusion and donor organs. We sought to determine the historical incidence of donor- and transfusion-acquired HCV infection in kidney transplant (RTx) and heart transplant (HTx) recipients at our center and to study the kinetics of seroconversion to HCV.

Methods: A bank of sera collected from organ donors (388 RTx and 88 HTx) who received allografts between January 1984 and April 1992 was screened for anti-HCV using a third generation enzyme immunoassay.

Alterations in the cardiopulmonary effects and pharmacokinetics of a bisphosphonate drug by a cytochrome P-450 inhibitor in conscious rats.

U-91502, a bisphosphonate for arthritic inflammation treatment, was evaluated for its parental toxicity. The objective was to differentiate between the parent drug and a reactive metabolite(s) as the proximate cause of the toxic effects using two methods. The first method was to block the metabolism of U-91502 with a broad-spectrum cytochrome P-450 inhibitor, 1-aminobenzotriazole (ABT), to increase its toxicity.

Cardiac assist devices.

The two primary goals of mechanical circulatory support are to provide adequate perfusion of the vital organs and to decrease cardiac work. The support of the myocardium is in an effort to cause a reversal of cardiac damage. The recovery process apparently takes place in two stages.

A potential anti-oxidant protein in a ferrous iron-oxidizing Sulfolobus species.

The production of a 25 kDa protein was greatly increased when a sulfur- and ferrous iron-oxidizing species of Sulfolobus was switched from growth on tetrathionate to growth on ferrous iron. The gene encoding the protein was cloned and sequenced. The predicted amino sequence showed significant similarity to those of the alkyl hydroperoxide reductase/thiol specific anti-oxidant family of proteins that appear to be involved in responses to certain types of oxidative stress.

Synovial sarcoma of the heart. Correlation with cytogenetic findings.

A primary sarcoma of the heart was submitted to cytogenetic studies, which showed a translocation t(X;18)(p11;q11.2). The translocation between X and 18 is a characteristic one in synovial sarcoma of the lower extremities.

Improved mortality and rehabilitation of transplant candidates treated with a long-term implantable left ventricular assist system.

Objective: This nonrandomized study using concurrent controls was performed to determine whether the HeartMate implantable pneumatic (IP) left ventricular assist system (LVAS) could provide sufficient hemodynamic support to allow rehabilitation of severely debilitated transplant candidates and to evaluate whether such support reduced mortality before and after transplantation.

Methods: Outcomes of 75 LVAS patients were compared with outcomes of 33 control patients (not treated with an LVAS) at 17 centers in the United States. All patients were transplant candidates who met the following hemodynamic criteria: pulmonary capillary wedge pressure > or = 20 mm Hg with a systolic blood pressure < or = 80 mm Hg or a cardiac index < or = 2.

Investigation by meta-analysis of the effect of prostaglandin F2 alpha administered post partum on the reproductive performance of dairy cattle.

The effects of injecting prostaglandin F2 alpha (PGF) in dairy cattle within 40 days of calving on the rate of pregnancy at first service and on the number of days open were investigated by meta-analysis, by pooling data from numerous independent trials into single analyses. A total of 4052 cows from 24 trials described in 10 papers were included in the analyses of first service pregnancy rate and 2646 cows from 21 trials described in nine papers in the analyses of the number of days open. The analyses were stratified by trial and by the reproductive health of the cows after calving.

Artificial circulatory support with textured interior surfaces. A counterintuitive approach to minimizing thromboembolism.

Background: Although numerous left ventricular assist devices (LVADs) have been used clinically, frequent thromboembolic complications have been reported despite the smooth interior LVAD surfaces and systemic anticoagulant medication. In contrast, the Thermo Cardiosystems HeartMate 1000 IP LVAD has textured interior surfaces that are promptly covered by a densely adherent neointima. We hypothesize that elimination of a direct interface between prosthetic material and blood elements reduces the risk of peripheral embolization and minimizes the necessity for systemic anticoagulant medication.

A cell-specific factor represses stimulation of transcription in vitro by transcriptional enhancer factor 1.

Transcription in HeLa cell extracts in vitro was stimulated 8- to 10-fold by a recombinant chimera, GAL-TEF-1, consisting of the DNA-binding domain of GAL4 and the activation function of the HeLa cell activator TEF-1. In contrast, only a 2- to 3-fold stimulation was obtained with GAL-TEF-1 in extracts from BJA-B lymphoid cells. Stimulation by GAL-TEF-1 in BJA-B extracts was dramatically increased by the addition of immunopurified HeLa cell TFIID, suggesting that BJA-B TFIID lacks or contains lower quantities of a TATA-binding-protein-associated factor(s) required for the activity of the TEF-1 activation function.

A reliable bridge to cardiac transplantation: the TCI left ventricular assist device.

The Thermo Cardiosystems (TCI) HeartMate, a pneumatically driven, implantable left ventricular assist device, was designed for long-term support of the failing heart. Between February 1990 and August 1992, the HeartMate was implanted in 11 heart transplant candidates because of profound deterioration of left ventricular function. Patients had a mean cardiac index of 1.

Design of novel cationic ligands for the purification of trypsin-like proteases by affinity chromatography.

A number of new cationic ligands have been designed and synthesized for the selective resolution and purification of the trypszin-like proteases. A series of ligands based on 4-[2'-methyl-4'-(2'',4''-dichloro-1'',3'',5''-triazin-6-ylamino ) phenylazo]benzamidine were able to bind to trypsin and the trypsin-like proteases, thrombin and urokinase, but bound pancreatic kallikrein only weakly. Ligands possessing a second cationic group (either 4-aminophenyltrimethylammonium or 4-aminobenzamidine) substituted onto the triazine ring displayed higher affinities than the parent compound for trypsin in solution but bound the enzyme weakly or not at all after immobilization.

Designer dyes: 'biomimetic' ligands for the purification of pharmaceutical proteins by affinity chromatography.

Affinity chromatography has been extensively refined over the past few years to meet the more stringent criteria being placed on recombinant proteins as therapeutic products. New developments in the design of selective and stable ligands for affinity chromatography are establishing the technique as a routine tool in process-scale protein purification. Exploitation of sophisticated molecular modelling techniques in conjunction with binding and crystallographic studies has permitted the design of new, highly selective 'biomimetic' ligands for the target proteins.

Multicenter clinical evaluation of the HeartMate 1000 IP left ventricular assist device.

The Thermo Cardiosystems Inc (Woburn, MA) HeartMate 1000 IP left ventricular assist device (LVAD) has been evaluated as a bridge to transplantation in 34 patients for up to 324 days at seven clinical centers in the United States. Sixty-five percent of the patients underwent transplantation, 80% of whom were discharged from the hospital. Six additional control patients, transplant candidates who met the entrance criteria but who did not receive the device, were also included in the study.

Design of novel affinity adsorbents for the purification of trypsin-like proteases.

A number of ligands for the selective purification by affinity chromatography of the trypsin-like protease, porcine pancreatic kallikrein, were designed de novo by computer-aided molecular design. The ligands were designed to mimic the side-chains of a number of arginyl dipeptides and included a benzamidine moiety substituted on a triazine ring. The ligands displayed inhibitory activities against pancreatic kallikrein which mirrored the specificity constants of the dipeptides they were designed to mimic.

Mediastinitis complicating successful mechanical bridge to heart transplantation.

A 22-year-old man with severe end-stage cardiomyopathy required placement of a left ventricular assist device. Purulent mediastinitis and peritonitis developed while the device was in place. The patient survived a prolonged course of treatment, with mediastinal and peritoneal irrigation and parenteral antibiotics, before undergoing a successful heart transplantation 12 weeks after placement of the left ventricular assist device.