Pre-discharge stress echocardiography and exercise ECG for risk stratification after uncomplicated acute myocardial infarction: results of the COSTAMI-II (cost of strategies after myocardial infarction) trial

OBJECTIVE

To compare in a prospective, randomised, multicentre trial the relative merits of pre-discharge exercise ECG and early pharmacological stress echocardiography concerning risk stratification and costs of treating patients with uncomplicated acute myocardial infarction.

DESIGN

262 patients from six participating centres with a recent uncomplicated myocardial infarction were randomly assigned to early (day 3-5) pharmacological stress echocardiography (n = 132) or conventional pre-discharge (day 7-9) maximum symptom limited exercise ECG (n = 130).

RESULTS

No complication occurred during either stress echocardiography or exercise ECG. At one year follow up there were 26 events (1 death, 5 non-fatal reinfarctions, 20 patients with unstable angina requiring hospitalisation) in patients randomly assigned to early stress echocardiography and 18 events (2 reinfarctions, 16 unstable angina requiring hospitalisation) in the group randomly assigned to exercise ECG (not significant). The negative predictive value was 92% for stress echocardiography and 88% for exercise ECG (not significant). Total costs of the two strategies were similar (not significant).

CONCLUSION

Early pharmacological stress echocardiography and conventional pre-discharge symptom limited exercise ECG have similar clinical outcome and costs after uncomplicated infarction. Early pharmacological stress echocardiography should be considered a valid alternative even for patients with interpretable baseline ECG who can exercise.

[Anti-hypertensive effect of eprosartan in diabetic patients]

OBJECTIVE

Diabetes mellitus seems to induce an special difficulty to control the high blood pressure. This effect is more severe on the SBP. Previous reports suggest that a new angiotensin receptor blocker, eprosartan, might have a higher efficacy to reduce SBP. It has been evaluated the BP decrease obtained with eprosartan in a group of diabetics patients compared to non diabetic patients.

MATERIAL AND METHODS

81 patients were recruited of whom 65 have ended follow-up. 34 patients were diabetics (mean age 66.7+/-10.7 years, 15 men and 19 women) and 31 were non diabetics control patients (mean age 61.8+/-12,8 years, 13 men and 18 women). All patients were treated with (600 mg) once daily. The doses was ingested in the morning. They were made three follow up visits (1, 3 and 6 mo after the first visit).

RESULTS

SBP was significantly decreased both in diabetics (baseline 170.9+/-12.0, final 139.1+/-13.0 mmHg, p < 0.001) and in non diabetics group (baseline 169.9+/-18.0, final 142.0+/-13.3 mmHg, p < 0.001). DBP was also reduced in both groups (diabetics: baseline 92.9+/-9.7, final 78.4+/-8.5 mmHg, p < 0.001; non diabetics: baseline 95.6+/-7.9, final 79.1+/-7.4 mmHg, p < 0.001). Differences between the groups were not significant in any visit. Final BP reduction reached was -31.7/-14.6 mmHg in diabetics vs -27,6/-16,5 mmHg in non diabetics patients (difference is not significant) Pulse pressure changes were not different between the two groups (diabetics, 17.8+/-14.5, vs non diabetics, 11.1+/-13.2 mmHg). Two diabetic patients need a second drug to achieve BP goal and no one in non diabetic group. No adverse effects were reported.

CONCLUSIONS

Eprosartan seems to be an effective drug to reduce SBP, DBP and pulse pressure with the same effectiveness in diabetics and non diabetic patients.

Sensitive and accurate quantitation of monoepoxy fatty acids in thermoxidized oils by gas-liquid chromatography

A sensitive and accurate methodology for quantitation of monoepoxy fatty acid methyl esters (FAME) by gas-liquid chromatography is proposed. Analytical problems of interfering compounds, ie, methyl monoester of azelaic acid and methyl docosanoate, were solved by a second methylation step with diazomethane and by elimination of nonpolar FAME by adsorption chromatography, respectively. Six monoepoxy FAME were identified and quantitated in olive and sunflower oils heated at 180 degrees C for 15 h: trans-9,10- and cis-9,10-epoxystearate coming from oleate and trans-12,13-, trans-9,10-, cis-12,13- and cis-9,10-epoxyoleate coming from linoleate. Results demonstrated total recovery of monoepoxy compounds after nonpolar FAME elimination with the additional advantage of sample concentration, which allowed quantitation of monoepoxy FAME in the initial oils. Also, repeatability was excellent as relative standard deviations ranged from 2.2 to 5.1% for on-column injection and from 0.1 to 2.0% for automatic split injection.

Antimicrobial activity of Pseudognaphalium moritzianum

The antimicrobial activity of ethanol, acetone and aqueous extracts of the aerial parts of Pseudognaphalium moritzianum was evaluated. Ethanol and acetone extracts showed activity against Staphlococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa. The aqueous extract was active against S. aureus and P. aeruginosa.

Ultrasonic assessment of oil quality during frying

In this paper, changes in ultrasonic properties during thermoxidation of virgin olive oil were studied. Samples of virgin olive oil were heated over different periods of time from 2 to 16 h at 200 degrees C. Oil degradation was characterized by means of physical and chemical changes, i.e., viscosity, color, polar compounds, polymers, and polar fatty acids. Ultrasonic measurements were carried out while the oil sample was cooled from 35 to 25 degrees C. It was found that velocity and attenuation measurements were related to viscosity measurements through a classical equation for viscous liquids. The ultrasonic measurements were also related to the percentages of polar compounds and polymers, which shows the feasibility of using ultrasonic properties to monitor oil quality. Nevertheless, as long as the ultrasonic measurements are temperature dependent, this variable must be controlled in order to obtain repetitive and reliable measurements.

The taenia solium glucose transporters TGTP1 and TGTP2 are not immunologically recognized by cysticercotic humans and swine

Cysticercosis caused by the metacestode of the tapeworm Taenia solium causes economic losses in pork meat production, as well as being a human health hazard in some parts of the world. In order to determine if the glucose transporters TGTPI and TGTP2 are recognized by antibodies in the sera from cysticercotic humans and pigs, western blot assays were carried out using membrane fractions of insect cells expressing the two T. solium glucose transporters. Results demonstrated a complete lack of recognition of both TGTPs. These results are unexpected, because at least one transporter is present on the apical surface of the cysticercus tegument.

The ddcA gene from Streptomyces fradiae encodes an extracellular beta-lactamase with penicillinase and cephalosporinase activities

The ddcA gene from Streptomyces fradiae, which is located adjacent to the left edge of the tylosin biosynthetic cluster, has been cloned and sequenced. DNA sequence analysis revealed an ORF of 1194 bp that encodes a product of 42.6 kDa. This protein showed significant similarity to the extracellular endopeptidase with beta-lactamase activity encoded by the adp gene from Bacillus cereus and to PBPs (DD-carboxypeptidases and DD-endopeptidases) and beta-lactamases. Moreover, it contains three characteristic motifs conserved in PBPs and beta-lactamases, including an essential serine residue in the active centre and a putative leader peptide. Heterologous expression of the ddcA gene in Streptomyces lividans demonstrated the presence in the transformants of an extracellular beta-lactamase active against penicillin G, ampicillin and the chromogenic cephalosporin nitrocefin.

Extracellular production of biologically active deacetoxycephalosporin C synthase from Streptomyces clavuligerus in Pichia pastoris

We have successfully expressed and observed secretion of the Streptomyces clavuligerus deacetoxycephalosporin C synthase (DAOCS) using the Pichia pastoris expression system. Two clones having multiple copies of the expression cassette were selected and used for protein-expression analysis. SDS-PAGE showed efficient expression and secretion of the bacterial recombinant DAOCS. The highest yield (120 microg/mL) was obtained when expression was induced with 2% methanol. Free and immobilized protein were assayed for biological activity and found to expand penicillin N (its natural substrate) and penicillin G to deacetoxycephalosporin C (DAOC) and deacetoxycephalosporin G (DAOG), respectively.

Cloning and characterization of the gene cahB encoding a cephalosporin C acetylhydrolase from Acremonium chrysogenum

An important problem during the production of cephalosporin C by Acremonium chrysogenum is the hydrolysis of cephalosporin C to deacetylcephalosporin C, since the latter compound has no commercial value and represents an unwanted side-product. Characterization of the enzymatic process that gives rise to deacetylcephalosporin C will help to avoid the accumulation of this side-product. An extracellular cephalosporin C acetylhydrolase (CPC-AH) from Acremonium chrysogenum C10 was purified to near homogeneity. This enzyme had a molecular mass of 31 kDa, a pl of 4.0, and showed relatively little affinity for cephalosporin C (Km 33.7 mM). We sequenced twenty amino acids at the amino-terminal end; a probe based on this sequence was then used to clone the cephalosporin acetylhydrolase (cahB) gene. cahB encodes a pre-protein of 383 amino acids with a deduced molecular mass of 38,228 Da. The sequenced 20 amino acids of the purified protein corresponded to amino acids 107-127 deduced from the cahB gene, suggesting that mature CPC-AH results from processing of the pre-protein after Gln-106. cahB is located on chromosome VIII of A. chrysogenum C10 and is not linked to the cephalosporin early or late gene clusters. It is expressed as a single 1.4-kb transcript after 72 h of cultivation. Expression declined in batch cultures after 120 h even though CPC-AH activity was observed until 144 h. The CPC-AH protein resembles other wide-spectrum substrate fungal esterases that are functionally related to serine proteases. The cahB gene does not seem to be related to the cephalosporin biosynthesis genes and encodes an esterase active on several substrates in addition to cephalosporin C.

Outcomes following extracranial carotid artery stenting in high-risk patients

BACKGROUND

Carotid artery angioplasty and stenting has become a viable alternative to carotid endarterectomy (CEA), especially for patients considered at high risk for post-operative complications. This study investigated the feasibility, safety and long-term outcome of carotid artery stenting (CAS) in high-risk patients.

METHODS

From July 1995 to November 2000, sixty-two consecutive patients considered to be at high risk for post-operative complications of CEA were followed prospectively after undergoing extracranial CAS procedures.

RESULTS

Sixty-two patients [37 men (60%) and 25 women (40%)] underwent a total of 69 CAS procedures. The mean age was 67 +/- 9 years (range, 32-89 years). Comorbid conditions included hypertension in 95% and severe coronary artery disease in 58%. Sixteen patients (26%) had a previous ipsilateral CEA, twenty-one percent had a history of neck radiation and 32% had a history of significant contralateral carotid artery disease. Fifty-two patients (84%) were symptomatic. All 69 CAS procedures were technically successful. The major post-operative complications were two minor strokes (2.8%), one major stroke (1.4%) and one fatal major stroke (1.4%). The mean length of follow-up was 17 months (range, 4 months to 5.6 years). Two patients (2.8%) have suffered ipsilateral neurologic events following CAS. Long-term follow-up revealed restenosis at 6 months in 4 patients (5.7%).

CONCLUSIONS

Carotid artery angioplasty and stenting is safe and feasible. This procedure produces satisfactory outcomes in patients who are at high risk for post-operative complications of CEA.

[Can the Brucellacapt test be substituted for the Coombs test in the diagnosis of human brucellosis?]

BACKGROUND

Throughout this work we have studied the capacity of Brucellacapt test to replace Coombs test in the serological diagnosis of human brucellosis.

METHODS

A total of 66 initial sera from patients with diagnostic of brucellosis were studied. The patients were divided in two groups: 42 patients showing a primo-infection (group1), and 24 patients with a previous case of brucellosis (group 2). As a controls, for the group 1 we have used 100 sera from healthy donors, and for group 2, 28 sera from people that have had clinical brucellosis but actually are in good health. All serum samples were tested in either Coombs and Brucellacapt tests. The diagnostic yield was calculated using ROC (receiver-operating characteristic) plots.Moreover, the results obtained in Coombs and Brucellacapt tests with 397 serum samples from 66 patients with brucellosis were compare with a non-parametric method.

RESULTS

The sensibility and specificity for group1 were respectively 1 and 0.98 for Coombs and, 1 and 0.95 for Brucellacapt tests. For group 2, the results in Coombs test were 1 and 0.80, and in Brucellacapt test 0.95 and 0.74. In this second group, the area under the ROC plot was 0.950 for Coombs and 0.904 for Brucellacapt tests. Non statistical differences were observed comparing both serological tests using the Wilcoxon method (Z= -0.213; p=0.8).

CONCLUSIONS

Brucellacapt and Coombs tests yield similar diagnostic results in the follow-up of serological samples from patients with brucellosis, and its should consider as interchangeables.

Structural analysis of BAG1 cochaperone and its interactions with Hsc70 heat shock protein

BAG-family proteins share a conserved protein interaction region, called the 'BAG domain', which binds and regulates Hsp70/Hsc70 molecular chaperones. This family of cochaperones functionally regulates signal transducing proteins and transcription factors important for cell stress responses, apoptosis, proliferation, cell migration and hormone action. Aberrant overexpression of the founding member of this family, BAG1, occurs in human cancers. In this study, a structure-based approach was used to identify interacting residues in a BAG1--Hsc70 complex. An Hsc70-binding fragment of BAG1 was shown by multidimensional NMR methods to consist of an antiparallel three-helix bundle. NMR chemical shift experiments marked surface residues on the second (alpha 2) and third (alpha 3) helices in the BAG domain that are involved in chaperone binding. Structural predictions were confirmed by site-directed mutagenesis of these residues, resulting in loss of binding of BAG1 to Hsc70 in vitro and in cells. Molecular docking of BAG1 to Hsc70 and mutagenesis of Hsc70 marked the molecular surface of the ATPase domain necessary for interaction with BAG1. The results provide a structural basis for understanding the mechanism by which BAG proteins link molecular chaperones and cell signaling pathways.

The gene encoding gamma-actin from the cephalosporin producer Acremonium chrysogenum

The nucleotide sequence of a 3240-bp genomic fragment including the gamma-actin-encoding gene from Acremonium chrysogenum has been determined, showing an open reading frame of 1691 bp, interrupted by five introns with fungal consensus splice-site junctions. The untranslated regions of the actA gene contain a consensus TATA box, a CCAAT motif, pyrimidine stretches and the polyadenylation sequence AATAA. The predicted protein (375 amino acids) revealed high identity to gamma-actins from fungi (> 90%). Gene phylogenies constructed using DNA and protein sequences support the grouping of A. chrysogenum actin close to those from the majority of the filamentous fungi. The actA gene is present as a single copy in the genome of A. chrysogenum; and its expression level, opposite to pcbC and cefEF cephalosporin biosynthetic genes, was steady during cephalosporin fermentation, showing a single 1.4-kb transcript.

Adjuvant radiotherapy for margin-positive high-grade soft tissue sarcoma of the extremity

PURPOSE

Adjuvant radiotherapy (RT) has been shown to improve local control in patients with soft tissue sarcoma of the extremities (STS). The specific impact of adjuvant radiation on patients with positive margins, however, has not been clearly defined. The purpose of this study was to determine if adjuvant RT improves local control in patients with high-grade STS who had positive margins of resection.

METHODS AND MATERIALS

Between 8/82 and 2/97, 110 adult patients with primary high-grade STS of an extremity underwent limb sparing surgery and were found to have a histologically positive microscopic surgical margin. Ninety-one (83%) received RT and 19 (17%) had no RT. The two groups were balanced with regard to size, site, location, and tumor depth. Adjuvant RT was delivered with brachytherapy (BRT) alone in 34 patients, external beam radiotherapy (EBRT) alone in 33 patients, or BRT+EBRT in 24 patients. The BRT dose was 45 Gy when used alone and 15-20 Gy when used as a boost. The EBRT dose was 60-70 Gy when used alone and 45-50 Gy when given with BRT. The median follow-up time was 41 months (range, 3-186 months).

RESULTS

The overall 5 year local control rate was 71%. This rate was significantly higher in the RT group compared to the no RT group (74% vs. 56%, respectively) (p = 0.01). On univariate analysis, lower extremity site and proximal location were also found to be predictors of improved local control (p = 0.03 and 0.03, respectively). However, only proximal location and the use of RT retained their significance as predictors of improved local control on multivariate analysis (p = 0.003 and 0.01, respectively). The overall 5-year distant relapse-free survival, disease-free survival, and overall survival rates were 54%, 44%, and 53%, respectively. No statistical differences were found in these survival rates between RT and no RT groups.

CONCLUSION

Based on this study, adjuvant radiotherapy seems to improve local control in patients with high-grade STS of the extremity with positive margins. However, local recurrence still occurs in a substantial proportion of patients, mandating further need for improvement.

Identification of two new translocations that disrupt the AML1 gene

The AML1 gene, located at chromosome 21q22, encodes a component (CBFalpha2) of a heterodimeric transcription factor complex termed core binding factor (CBF), which binds to DNA and activates gene expression. Chromosomal rearrangements may lead to disruption of this gene and development of acute leukemia. Twelve AML1 translocations have been identified to date, and include sites on chromosomes 1, 2, 3, 5, 8, 12, 14, 15, 16, 17, 18, and 19. Here we report two new translocations involving AML1 in acute myeloid leukemia, in which the disruption of the AML1 gene was documented by GTG banding cytogenetic studies and metaphase and interphase FISH analysis. These chromosomal breakpoints identified as harboring new fusion partners for AML1 are at 2p11.2 and 20q13.1. The two patients in who these translocation were identified were elderly males with newly diagnosed AML. These patients shared the same poor outcomes reported for other rare AML1 translocations.

A cephalosporin C acetylhydrolase is present in the cultures of Nocardia lactamdurans

Two protein bands with strong esterase activity are present in broths of Nocardia lactamidurans MA4213 cultures. One of them shows cephalosporin C acetylhydrolase (CAH) activity. This activity is maximal at 48 h of growth and shows a pattern of regulation slightly different from that of cephamycin production in medium supplemented with glucose (166 mM), glycerol (326 mM) or ammonium chloride (60 mM). The CAH activity was purified to homogeneity by DEAE-Sepharose ion-exchange, Sephadex G-75 gel filtration, and phenyl-Sepharose hydrophobic interaction chromatography. It showed a molecular mass of 72,100 Da. The N-terminus of the protein was determined and showed the amino acid sequence GGAAPGGPGAHPLWLPAGKD. The enzyme showed Km values of 7.0 mM and 8.3 mM for cephalosporin C and 7-aminocephalosporanic acid respectively but was not active on cephamycin C.

Environmentally safe production of 7-aminodeacetoxycephalosporanic acid (7-ADCA) using recombinant strains of Acremonium chrysogenum

Medically useful semisynthetic cephalosporins are made from 7-aminodeacetoxycephalosporanic acid (7-ADCA) or 7-aminocephalosporanic acid (7-ACA). Here we describe a new industrially amenable bioprocess for the production of the important intermediate 7-ADCA that can replace the expensive and environmentally unfriendly chemical method classically used. The method is based on the disruption and one-step replacement of the cefEF gene, encoding the bifunctional expandase/hydroxylase activity, of an actual industrial cephalosporin C production strain of Acremonium chrysogenum. Subsequent cloning and expression of the cefE gene from Streptomyces clavuligerus in A. chrysogenum yield recombinant strains producing high titers of deacetoxycephalosporin C (DAOC). Production level of DAOC is nearly equivalent (75-80%) to the total beta-lactams biosynthesized by the parental overproducing strain. DAOC deacylation is carried out by two final enzymatic bioconversions catalyzed by D-amino acid oxidase (DAO) and glutaryl acylase (GLA) yielding 7-ADCA. In contrast to the data reported for recombinant strains of Penicillium chrysogenum expressing ring expansion activity, no detectable contamination with other cephalosporin intermediates occurred.

Brucella abortus and its closest phylogenetic relative, Ochrobactrum spp., differ in outer membrane permeability and cationic peptide resistance

The outer membrane (OM) of the intracellular parasite Brucella abortus is permeable to hydrophobic probes and resistant to destabilization by polycationic peptides and EDTA. The significance of these unusual properties was investigated in a comparative study with the opportunistic pathogens of the genus Ochrobactrum, the closest known Brucella relative. Ochrobactrum spp. OMs were impermeable to hydrophobic probes and sensitive to polymyxin B but resistant to EDTA. These properties were traced to lipopolysaccharide (LPS) because (i) insertion of B. abortus LPS, but not of Escherichia coli LPS, into Ochrobactrum OM increased its permeability; (ii) permeability and polymyxin B binding measured with LPS aggregates paralleled the results with live bacteria; and (iii) the predicted intermediate results were obtained with B. abortus-Ochrobactrum anthropi and E. coli-O. anthropi LPS hybrid aggregates. Although Ochrobactrum was sensitive to polymyxin, self-promoted uptake and bacterial lysis occurred without OM morphological changes, suggesting an unusual OM structural rigidity. Ochrobactrum and B. abortus LPSs showed no differences in phosphate, qualitative fatty acid composition, or acyl chain fluidity. However, Ochrobactrum LPS, but not B. abortus LPS, contained galacturonic acid. B. abortus and Ochrobactrum smooth LPS aggregates had similar size and zeta potential (-12 to -15 mV). Upon saturation with polymyxin, zeta potential became positive (1 mV) for Ochrobactrum smooth LPS while remaining negative (-5 mV) for B. abortus smooth LPS, suggesting hindered access to inner targets. These results show that although Ochrobactrum and Brucella share a basic OM pattern, subtle modifications in LPS core cause markedly different OM properties, possibly reflecting the adaptive evolution of B. abortus to pathogenicity.

Stenting in a patient with a single coronary artery and myocardial infarction

The single coronary artery is an uncommon congenital defect. We report on a patient admitted to our hospital with an acute myocardial infarction and a single coronary artery arising from the left sinus of Valsalva who was treated with coronary angioplasty and stent implantation. We have not found an identical report of stenting in such an anomaly in the medical literature.