[Stress echocardiography in the identification of left anterior descending coronary artery disease in patients with inferior myocardial infarction and a positive exercise electrocardiography result]

INTRODUCTION AND OBJECTIVES

In patients with an inferior myocardial infarction (IMI), ST-segment depression in left precordial leads during exercise electrocardiography (ExECG) has been associated with left anterior descending coronary artery (LADCA) disease. The aim of this study was to assess the value of stress echocardiography in identifying LADCA disease in patients with IMI and a highly abnormal ExECG result.

METHODS

The study included patients with an IMI and an abnormal ExECG result whose coronary angiography findings were available. A highly abnormal ExECG result was defined as ST-segment depression in three or more leads, including V5. The wall motion score index was calculated and each patient was evaluated echocardiographically for ischemia in LADCA territory.

RESULTS

Of 241 patients who underwent stress ECG, 100 (mean age 57 [11] years) met inclusion criteria. Some 38 had significant LADCA stenosis and, in 75, ExECG gave a highly abnormal result. The sensitivity, specificity and accuracy of a highly abnormal ExECG result for detecting LADCA disease were 74% (60%-88%), 26% (15%-37%), and 44% (34%-54%), respectively. Echocardiographic detection of ischemia had similar sensitivity, at 74%, but higher specificity, at 92% (P< .001), and accuracy, at 85% (P< .001). Multivariate analysis of clinical, exercise test, and stress echocardiography variables revealed that the only independent predictors of LADCA disease were age (OR=1.070), recent IMI (OR=0.136), and ischemia in LADCA territory (OR=19.9).

CONCLUSIONS

Stress echocardiography is a good noninvasive technique for detecting LADCA disease in patients with an IMI. The diagnostic accuracy of a highly abnormal ExECG result is not sufficient for its use in this clinical setting.

Sensorineural hearing loss in insulin-like growth factor I-null mice: a new model of human deafness

It has been reported that mutations in the gene encoding human insulin-like growth factor-I (IGF-I) cause syndromic hearing loss. To study the precise role of IGF-I in auditory function and to hypothesize the possible morphological and electrophysiological changes that may occur in the human inner ear, we have analysed the auditory brainstem response in a mouse model of IGF-I deficiency. We show here that homozygous Igf-1(-/-) mice present an all-frequency involved bilateral sensorineural hearing loss. Igf-1(-/-) mice also present a delayed response to acoustic stimuli; this increases along the auditory pathway, indicating a contribution of the central nervous system to the hearing loss in Igf-1(-/-) mice. These results support the use of the Igf-1(-/-) mouse as a new model for the study of human syndromic deafness.

Abel inversion applied to a small set of emission data from a microwave plasma

In this work we propose a criterion to apply the Abel inversion in the case of a small set of experimental data to be used in laboratory plasmas. The Nestor-Olsen method, spline interpolation, and Fourier transform Abel inversion have been compared in order to study the influence of statistical noise and the number of sampled data. The application of this criterion permits us to obtain a radial distribution of the plasma parameters (densities and temperatures) from the spectral line profiles emitted by the discharge. The proposed criterion has been tested using the lateral intensities of several lines emitted by a microwave helium plasma column generated at atmospheric pressure.

Growth of hydroxyapatite in a biocompatible mesoporous ordered silica

A novel biomaterial (HA-SBA-15) has been developed based on the growth of calcium phosphate hydroxyapatite (HA) nanoparticles within an organized silica structure (SBA-15). Characterization of the material was carried out using a combination of X-ray diffraction, X-ray fluorescence, transmission electron microscopy, N2 adsorption-desorption isotherms and nuclear magnetic resonance. Transmission electron microscopy observations and N2 porosimetry revealed the crystallization of hydroxyapatite nanoparticles inside the mesopore cavities of the silica structure. Specific surface areas of 760 m2 g(-1) and 260 m2 g(-1) were measured for the SBA-15 and the HA-SBA-15 material, respectively. The hydroxyl groups present in the silica nanostructure surface have brought about cationic defects in the silicium sites, mainly with those of tetrahedral symmetry, and promoted the formation of siloxanes. 29Si MAS-NMR analysis shows a significant reduction of the silanol groups concentration with HA growing within the base (SBA-15) material. Studies and brain tissue biocompatibility tests were carried out. Histopathological studies on the SBA-15 implant material showed no changes to the tissue nearby. The results confirmed the synthesis of a silica-based composite containing HA nanoparticles with the potential for biomedical applications.

[Perception of difficulties in family medicine in the delivery of health to economic immigrants]

OBJECTIVES

To find the problems, as seen by family doctors, in care for immigrants, with description of proposed solutions.

DESIGN

Transversal and descriptive.

PARTICIPANTS

262 doctors from 18 health centres in a district.

MEASUREMENTS

Each professional received a questionnaire containing social and demographic variables, number of immigrants seen per day, their place of origin, 6 items on accessibility, 5 on barriers to care, 6 on clinic, and 7 on solutions.

RESULTS

159 doctors, 57.2% women, replied. Average age was 41.1; 64% saw 2-3 immigrants a day. 52.3% (95% CI, 45.0%-61.4%) recognised that care for immigrants posed professional problems. They said that immigrants attended as an emergency more often (81.1%); they more often had no clinical records (74.7%); and they had difficulties obtaining a health card (53%). 67% expressed no difficulties for getting to the hospital. Perceived barriers were the mobility of immigrants (82.9%), language (82.3%), and culture (71.3%). Solutions suggested were translators (95.6%) or cultural intermediary (82.7%). Clinically, doctors saw no differences of pathology in immigrants (56.7%), and no greater psychiatric pathology (66%). Lack of skill in contagious pathologies hampered care (60.3%). 82.8% affirmed that specific protocols were needed. 80.3% argued for a unit of imported diseases. Among care priorities were information on health circuits and making the health card easier to obtain.

CONCLUSIONS

The difficulties sustained by a broad range of professionals are diverse, with access and linguistic-cultural questions standing out. To palliate them, sensitivity from health staff and action from management are needed.

[Influence of the nasogastric tube in the pathology of the maxillary sinus]

INTRODUCTION

Nasoesophageal tube (NT) is very often used by the ear, nose and throat specialists in head and neck oncological surgery. It is well known the irritative effect that it has on the nasosinusal mucosa. The aim of this study is to analyze the relationship between the use of the NT and the pathology of the maxillary sinuses.

MATERIAL AND METHOD

The study was carried out in 25 patients treated in our department who had been fed by NT, after surgery. A plain sinus X-ray was performed in the pre-operatory period and a control radiograph in the post-operatory period, and the results have been analyzed.

RESULTS AND CONCLUSIONS

No sinusitis had been observed whatever length of time the NT remained in situ.

[Clinical picture and prognostic factors for severe community-acquired pneumonia in adults admitted to the intensive care unit]

OBJECTIVE

In Chile very little information is available on severe community-acquired pneumonia treated in intensive care units. This study describes the clinical picture, prognostic factors, and treatment of adult patients admitted to the intensive care unit for severe community-acquired pneumonia.

PATIENTS AND METHODS

A total of 113 consecutive patients were included in this prospective, descriptive study.

RESULTS

The mean (SD) age of the 113 patients was 73 (15). Of these, 95% had associated comorbidity, and 81% were in the high-risk classes of the Pneumonia Severity Index. Etiology was identified in 31%, and the most common pathogens were Streptococcus pneumoniae (40%), gram negative bacilli (17%), and Mycoplasma pneumoniae (6%). The main complications were the need for mechanical ventilation (45%), septic shock (26%), heart failure (24%), and arrhythmias (15%). Mortality at 30 days was 16.8%, and multivariate analysis revealed the following factors to be associated with a greater risk of death: acute renal failure (odds ratio: 5.1), and glycemia above 300 mg/dL (odds ratio: 7.2).

CONCLUSIONS

The patients with severe pneumonia admitted to the intensive care unit are elderly, with a high level of comorbidity and complications, but most survive.

[Behaviour of vancomycin with the new techniques in haemodialysis]

When using high convection dialysis techniques it arouses the necessity of considering the suitability of the regular protocols when administrating drugs, such as vancomycin.

OBJECTIVES

To confirm if the usual guideline of vancomycin is efficient in patients undergoing treatments with acetate free biofiltration (AFB) and haemodiafiltration on-line (on-line). To propose an alternative guideline of administration.

MATERIAL AND METHODS

13 patients treated with AFB or On-line. 10 of them used filters of polysulfone and 3 of them of AN69. First part: 6 patients were administered 1 g iv during the last hour of dialysis. Second part: 7 patients were given a loading dose of 30 mg/kg iv with a reinforcement of 500 mg post-dialysis. The blood levels of the antibiotic were monitorized during the week following the administration.

OUTCOMES

During the first phase it was noticed a decrease of 41% in the serum level of vancomycin during dialysis, conditioning subtherapeutic levels in the 83% of the patients until the end of the study. As for the second phase, therapeutic non-toxic levels were maintained during the whole study. The existence of a post-dialysis rebound of the 21 % was confirmed. A bigger clearance of vancomycin was obtained with the On-line technique rather than with AFB (176 vs 135 ml/min). We find a strong correlation between the decrease of the antibiotic and the volume ultrafiltrated with the On-line technique.

CONCLUSIONS

The usual guideline of vancomycin may not be enough with the new convective dialysis techniques. A guideline based on a loading dose of 30 mg/kg and a reinforcement of 500 mg at the end of each dialysis could be adequate. The antibiotic clearance with the On-line technique is probably made by convective transport.

Scorpion envenoming in two regions of Colombia: clinical, epidemiological and therapeutic aspects

To determine clinical and epidemiological features of scorpion stings in two departments of Colombia, a descriptive study was performed in the hospitals of 10 towns from Antioquia (2 256 071 inhabitants) and five from Tolima (630 424 inhabitants). One hundred and twenty-nine cases were admitted during one year, 51 in Antioquia, 78 in Tolima and 41 were children less than 15 years old. Most stings (70.5%) occurred inside the house; 27.9% were on the hands and 26.4% on the feet. The scorpion species involved were Tityus pachyurus (51), Centruroides gracilis (31), T. fuehrmanni (29), T. asthenes (7) and Chactas spp. (1). In 10 cases the scorpion involved was not identified. Systemic envenoming signs (e.g. vomiting, tachypnea) were significantly more frequent in children than in adults (P < 0.05). Four children had hypertension, but none developed pulmonary oedema. One 3-year-old girl, stung by T. asthenes, had acute oedematous pancreatitis. Ninety-eight patients had mild envenoming. Moderate (27 patients) and severe (four patients) envenoming was significantly more frequent in children than in adults (P = 0.003; relative risk = 2.97). A pepsin-digested anti-Centruroides spp. antivenom was administered to 19 of 31 patients presenting systemic envenoming signs. No adverse reactions to antivenom were observed.

Neutralization of the edema-forming, defibrinating and coagulant effects of Bothrops asper venom by extracts of plants used by healers in Colombia

We determined the neutralizing activity of 12 ethanolic extracts of plants against the edema-forming, defibrinating and coagulant effects of Bothrops asper venom in Swiss Webster mice. The material used consisted of the leaves and branches of Bixa orellana (Bixaceae), Ficus nymphaeifolia (Moraceae), Struthanthus orbicularis (Loranthaceae) and Gonzalagunia panamensis (Rubiaceae); the stem barks of Brownea rosademonte (Caesalpiniaceae) and Tabebuia rosea (Bignoniaceae); the whole plant of Pleopeltis percussa (Polypodiaceae) and Trichomanes elegans (Hymenophyllaceae); rhizomes of Renealmia alpinia (Zingiberaceae), Heliconia curtispatha (Heliconiaceae) and Dracontium croatii (Araceae), and the ripe fruit of Citrus limon (Rutaceae). After preincubation of varying amounts of each extract with either 1.0 microg venom for the edema-forming effect or 2.0 microg venom for the defibrinating effect, the mixture was injected subcutaneously (sc) into the right foot pad or intravenously into the tail, respectively, to groups of four mice (18-20 g). All extracts (6.2-200 microg/mouse) partially neutralized the edema-forming activity of venom in a dose-dependent manner (58-76% inhibition), with B. orellana, S. orbicularis, G. panamensis, B. rosademonte, and D. croatii showing the highest effect. Ten extracts (3.9-2000 microg/mouse) also showed 100% neutralizing ability against the defibrinating effect of venom, and nine prolonged the coagulation time induced by the venom. When the extracts were administered either before or after venom injection, the neutralization of the edema-forming effect was lower than 40% for all extracts, and none of them neutralized the defibrinating effect of venom. When they were administered in situ (sc at the same site 5 min after venom injection), the neutralization of edema increased for six extracts, reaching levels up to 64% for C. limon.

Cross-amplification and sequence variation of microsatellite loci in Eurasian hard pines

Microsatellite transfer across coniferous species is a valued methodology because de novo development for each species is costly and there are many species with only a limited commodity value. Cross-species amplification of orthologous microsatellite regions provides valuable information on mutational and evolutionary processes affecting these loci. We tested 19 nuclear microsatellite markers from Pinus taeda L. (subsection Australes) and three from P. sylvestris L. (subsection Pinus) on seven Eurasian hard pine species ( P. uncinata Ram., P. sylvestris L., P. nigra Arn., P. pinaster Ait., P. halepensis Mill., P. pinea L. and P. canariensis Sm.). Transfer rates to species in subsection Pinus (36-59%) were slightly higher than those to subsections Pineae and Pinaster (32-45%). Half of the trans-specific microsatellites were found to be polymorphic over evolutionary times of approximately 100 million years (ten million generations). Sequencing of three trans-specific microsatellites showed conserved repeat and flanking regions. Both a decrease in the number of perfect repeats in the non-focal species and a polarity for mutation, the latter defined as a higher substitution rate in the flanking sequence regions close to the repeat motifs, were observed in the trans-specific microsatellites. The transfer of microsatellites among hard pine species proved to be useful for obtaining highly polymorphic markers in a wide range of species, thereby providing new tools for population and quantitative genetic studies.

Cross-amplification and sequence variation of microsatellite loci in Eurasian hard pines

Microsatellite transfer across coniferous species is a valued methodology because de novo development for each species is costly and there are many species with only a limited commodity value. Cross-species amplification of orthologous microsatellite regions provides valuable information on mutational and evolutionary processes affecting these loci. We tested 19 nuclear microsatellite markers from Pinus taeda L. (subsection Australes) and three from P. sylvestris L. (subsection Pinus) on seven Eurasian hard pine species ( P. uncinata Ram., P. sylvestris L., P. nigra Arn., P. pinaster Ait., P. halepensis Mill., P. pinea L. and P. canariensis Sm.). Transfer rates to species in subsection Pinus (36-59%) were slightly higher than those to subsections Pineae and Pinaster (32-45%). Half of the trans-specific microsatellites were found to be polymorphic over evolutionary times of approximately 100 million years (ten million generations). Sequencing of three trans-specific microsatellites showed conserved repeat and flanking regions. Both a decrease in the number of perfect repeats in the non-focal species and a polarity for mutation, the latter defined as a higher substitution rate in the flanking sequence regions close to the repeat motifs, were observed in the trans-specific microsatellites. The transfer of microsatellites among hard pine species proved to be useful for obtaining highly polymorphic markers in a wide range of species, thereby providing new tools for population and quantitative genetic studies.

Synthesis and odour thresholds of mixed halogenated anisoles in water

Earthy-musty off-flavour compounds in water samples are usually associated with the presence of geosmin and 2-methylisoborneol. However, the presence of 2,3,6- and 2,4,6-trichloroanisoles or other halogenated anisoles can impart objectionable tastes and odours to the water even at very low trace levels. This paper shows the synthesis of non-commercial 2,3,6- and 2,4,6- mixed chloro/bromoanisoles which can be present in bromide rich waters and could also be suspected of imparting earthy-musty off-flavours to the water. All the synthesized compounds were subjected to the flavour profile analysis (FPA) method and their odour threshold concentrations (OTC) in water were carried out giving values in the low ng/L range.

[Intranasal approaches for pituitary area tumors. Our experience]

Transsphenoidal approach is the most commonly employed surgical technique for the resection of pituitary tumors. We present our experience in the transnasal-transsphenoidal approach in 30 patients undergoing pituitary surgery from 1998 to 2002. Ten patients underwent surgery via a sublabial-transeptal-transsphenoidal approach, 15 patients via a transeptal-transsphenoidal approach and 5 patients via a pure endoscopic transnasal-transsphenoidal. The pathological study showed 29 pituitary adenomas and 1 Rathe's cleft cyst. We conclude that the pure endoscopic transnasal-transsphenoidal approach guided by a navigator-system is safest and more effective approach. We reserved the transeptal-transsphenoidal approach for cases with obstructive septal deflection and poor pneumatized sphenoid sinuses. We do not recommend the use of the sublabial-trans-sphenoidal approach.

[Evaluation of osteodystrophy parameters in a pre-dialysis unit]

A cross-sectional study was developed with 100 of the first-time pre-dialysis patients visiting the Princesa University Hospital's Advanced Chronic Kidney Disease (ACKD) unit, with the aim of analysing various parameters of osteodystrophy at this time. Parameters evaluated were: age, gender, renal function, osteodystrophy serum parameters, comorbidity index (ICED) and the patients' origin to establish correlations between these parameters. Mean iPTH levels were higher irrespective of the patients' origin, and were significantly higher in men than in women, the former also having poorer renal function and higher comorbidity score. The mean levels of calcium, phosphorous, alkaline phosphatase and CO2 did not justify this rise in iPTH. Nutritional parameters NPNA and albumin were adequate in spite of ageing. At early stages of ESRD, iPTH could be elevated and ACKD units play an important part its early detection and subsequent treatment.

Oogenesis and plasma levels of sex steroids in cultured females of brown trout (Salmo trutta linnaeus, 1758) in Chile

Naturalized brown trout populations in Chile are a valuable genetic resource with aquaculture potential. The oogenesis of a three-year-old brown trout cultured population was studied in southern Chile. Gonadosomatic index (GSI), oocyte growth, gonadal microscopic characteristics, and plasma levels of estradiol-17beta (E2), testosterone (T), and 17alpha-hydroxyprogesterone (17alpha-HP) were measured bimonthly for a nine-month period before spawning. The maximum GSI level (22%) was similar to that described for other salmonids, although it was reached in May, more than one month before the population started spawning. Oocyte growth increases strongly from January when diameter reaches more than 1 mm. The vitellogenic period (six-seven months) is consistent with the long vitellogenesis, described for salmonid females maturing at three years old. E2 shows a slow increase from November, reaching its peak value in March (65.2+/-0.7 ng/ml), during maximal vitellogenic activity. T increases as oogenesis progresses, reaching a maximum of 90+/-20 ng/ml during May, and falling considerably during ovulation. Following a typical pattern of progestogens in salmonid oogenesis, 17alpha-HP stays at basal levels during most of oogenesis, but experiences a strong surge (2.0+/-0.4 ng/ml) just before ovulation.

Production and partial characterization of a beta-amylase by Xanthophyllomyces dendrorhous

AIMS

The characterization of a beta-amylase produced by Xanthophyllomyces dendrorhous.

METHODS AND RESULTS

Growth in different culture media showed that X. dendrorhous produces an amylase whose synthesis is repressed by the carbon source and induced by starch and maltose. Enzymatic assays using substrates with different degrees of polymerization together with viscosity experiments revealed that the enzyme was beta-amylase. According to the biochemical characterization, the enzyme has a molecular weight of 240 kDa and a Km of 1.35 mg ml-1. The optimum pH and temperature were 5.5 and 50 degrees C, respectively. Using different inhibitors of the enzymatic activity it was shown that cysteine, tryptophan and serine are essential amino acids for catalysis.

CONCLUSIONS

Xanthophyllomyces dendrorhous CECT1690 synthesizes and secretes beta-amylase that could be a by-product, in addition to carotenoid pigments, in the fermentation downstream.

SIGNIFICANCE AND IMPACT OF THE STUDY

The beta-amylase produced by X. dendrorhous may have certain industrial applications.

Inverted papilloma of the sphenoid sinus

Inverted nasosinusal papilloma is a benign tumor accounting for less than 4% of all nasal masses. The lesion originates in the mucosa lining the nasal cavities, the locations in decreasing order of frequency being the lateral wall of the nasal fossa, ethmoid sinus, and maxillary sinus; the sphenoid sinus is only rarely affected. Despite its benign histology, the tumor shows aggressive behavior and can be associated to carcinomas. Surgery is therefore indicated in such cases.

Cloning and expression of Blo t 1, a novel allergen from the dust mite Blomia tropicalis, homologous to cysteine proteases

BACKGROUND

House dust mite allergens have been shown to be a very important stimulus in the causation of asthma and triggers for the exacerbation of symptoms. Therefore, characterization of mite-derived allergens at the molecular level is an important step for the development of effective diagnostic and therapeutic approaches, as well as for epidemiological studies.

OBJECTIVE

To clone, express and characterize at the molecular level the cysteine protease from Blomia tropicalis (Bt).

METHODS

A full-length cDNA encoding Blo t 1 was cloned from a Bt cDNA library using a PCR and RACE-based strategy. The cDNA was PCR-amplified, sequenced and subcloned into a prokaryotic expression vector. The allergenicity of the recombinant Blo t 1 was evaluated for IgE reactivity by Western blot.

RESULTS

Blo t 1 cDNA encodes a 221 amino acids polypeptide with an estimated molecular weight of 25 kDa. The recombinant protein is 35% identical to other mite cysteine proteases. Recombinant Blo t 1 (rBlo t 1) bound IgE from 62% of Bt skin test-positive serum. Dermatophagoides pteronyssinus (Dp) skin test-positive sera did not react with rBlo t 1, indicating the possible presence of unique IgE epitopes on the rBlo t 1 molecule. A three-dimensional image of Blo t 1, constructed based on predicted analysis, showed conserved secondary and tertiary structure with other cysteine proteases.

CONCLUSION

We report the cloning, expression and IgE reactivity of Blo t 1, a novel allergen from the domestic mite Blomia tropicalis (Bt), highly homologous to cysteine proteases. This putative cysteine protease, designated Blo t 1, may play a major role as an immunodominant allergen involved in dust mite-specific IgE-mediated hypersensitivity.

Regulation of mu-opioid receptors, G-protein-coupled receptor kinases and beta-arrestin 2 in the rat brain after chronic opioid receptor antagonism

The aim of this study was to analyse the biochemical and behavioural consequences of chronic treatment with opioid receptor antagonists in rats. We have evaluated the respiratory depressant and antinociceptive effects of the mu-opioid agonist sufentanil, the density of brain mu-opioid receptors, and the expression of G-protein-coupled receptor kinases and beta-arrestin 2 in cerebral cortex and striatum, following sustained opioid receptor blockade. Our results demonstrate that 24 h after interruption of 7 days chronic infusion of naltrexone (120 microg/h), the respiratory depressant potency of the mu-opioid receptor agonist sufentanil was increased to a similar extent as the antinociceptive potency (about three-fold). This was accompanied by mu-opioid receptor up-regulation in several areas of the rat brain associated with opioid control of pain perception and breathing. Moreover, chronic treatment with either naltrexone (120 microg/h) or naloxone (120 microg/h) caused significant increases in the expression levels of G-protein-coupled receptor kinases types 2, 3, and 6, and of beta-arrestin 2 in brain cortex and striatum. Together our data suggest an increased constitutive receptor activity secondary to mu-opioid receptor up-regulation following chronic antagonist treatment.