Integrating ecotoxicity and chemical approaches to compare the effects of ZnO nanoparticles, ZnO bulk, and ZnCl2 on plants and microorganisms in a natural soil

This work compared the toxicity of ZnO nanoparticles (ZnO-NPs), ZnO bulk, and ZnCl2 on microbial activity (C and N transformations and dehydrogenase and phosphatase activities) and their uptake and toxic effects (emergence, root elongation, and shoot growth) on three plant species namely wheat, radish, and vetch in a natural soil at 1000 mg Zn kg(-1). Additionally, plants were also tested at 250 mg Zn kg(-1). The effects of the chemical species on Zn extractability in soil were studied by performing single and sequential extractions. ZnCl2-1000 presented the highest toxicity for both taxonomic groups. For microorganisms, ZnO-NPs demonstrated adverse effects on all measured parameters, except on N transformations. The effects of both ZnO forms were similar. For plants, ZnO-NPs affected the growth of more plant species than ZnO bulk, although the effects were small in all cases. Regarding accumulation, the total Zn amounts were higher in plants exposed to ZnO-NP than those exposed to ZnO bulk, except for vetch shoots. The soil sequential extraction revealed that the Zn concentration in the most labile forms (water soluble (WS) and exchangeable (EX)) was similar in soil treated with ZnO (NP and bulk) and lower than that of ZnCl2-treated soil, indicating the higher availability of the ionic forms. The strong correlations obtained between WS-Zn fraction and the Zn concentrations in the roots, shoots, and the effects on shoot weight show the suitability of this soil extraction method for predicting bioavailable Zn soil for the three plant species when it was added as ZnO-NPs, ZnO bulk, or ZnCl2. In this work, the hazard associated with the ZnO-NPs was similar to ZnO bulk in most cases.

Generation and evaluation of typical meteorological year datasets for greenhouse and external conditions on the Mediterranean coast

A typical meteorological year (TMY) represents the typical meteorological conditions over many years but still contains the short term fluctuations which are absent from long-term averaged data. Meteorological data were measured at the Experimental Station of Cajamar 'Las Palmerillas' (Cajamar Foundation) in Almeria, Spain, over 19 years at the meteorological station and in a reference greenhouse which is typical of those used in the region. The two sets of measurements were subjected to quality control analysis and then used to create TMY datasets using three different methodologies proposed in the literature. Three TMY datasets were generated for the external conditions and two for the greenhouse. They were assessed by using each as input to seven horticultural models and comparing the model results with those obtained by experiment in practical trials. In addition, the models were used with the meteorological data recorded during the trials. A scoring system was used to identify the best performing TMY in each application and then rank them in overall performance. The best methodology was that of Argiriou for both greenhouse and external conditions. The average relative errors between the seasonal values estimated using the 19-year dataset and those using the Argiriou greenhouse TMY were 2.2 % (reference evapotranspiration), -0.45 % (pepper crop transpiration), 3.4 % (pepper crop nitrogen uptake) and 0.8 % (green bean yield). The values obtained using the Argiriou external TMY were 1.8 % (greenhouse reference evapotranspiration), 0.6 % (external reference evapotranspiration), 4.7 % (greenhouse heat requirement) and 0.9 % (loquat harvest date). Using the models with the 19 individual years in the historical dataset showed that the year to year weather variability gave results which differed from the average values by ± 15 %. By comparison with results from other greenhouses it was shown that the greenhouse TMY is applicable to greenhouses which have a solar radiation transmission of approximately 65 % and rely on manual control of ventilation which constitute the majority in the south-east of Spain and in most Mediterranean greenhouse areas.

Toxicity of ZnO nanoparticles, ZnO bulk, and ZnCl₂ on earthworms in a spiked natural soil and toxicological effects of leachates on aquatic organisms

The present study assessed the uptake and toxicity of ZnO nanoparticles (NPs), ZnO bulk, and ZnCl₂ salt in earthworms in spiked agricultural soils. In addition, the toxicity of aqueous extracts to Daphnia magna and Chlorella vulgaris was analyzed to determine the risk of these soils to the aquatic compartment. We then investigated the distribution of Zn in soil fractions to interpret the nature of toxicity. Neither mortality nor differences in earthworm body weight were observed compared with the control. The most sensitive end point was reproduction. ZnCl₂ was notably toxic in eliminating the production of cocoons. The effects induced by ZnO-NPs and bulk ZnO on fecundity were similar and lower than those of the salt. In contrast to ZnO bulk, ZnO-NPs adversely affected fertility. The internal concentrations of Zn in earthworms in the NP group were greater than those in the salt and bulk groups, although bioconcentration factors were consistently <1. No relationship was found between toxicity and internal Zn amounts in earthworms. The results from the sequential extraction of soil showed that ZnCl₂ displayed the highest availability compared with both ZnO. Zn distribution was consistent with the greatest toxicity showed by the salt but not with Zn body concentrations. The soil extracts from both ZnO-NPs and bulk ZnO did not show effects on aquatic organisms (Daphnia and algae) after short-term exposure. However, ZnCl₂ extracts (total and 0.45-μm filtered) were toxic to Daphnia.

[A school breaks card game improves eating habits in adolescents]

INTRODUCTION

Feeding habits among the Spanish population are currently an increasing and concerning problem, especially during adolescence.

OBJECTIVES

To improve feeding habits (breakfast, consumption of fruit and water, soft drinks, pastries, sweets and fried food) in adolescents.

METHODS

The intervention was conducted for 3 months in students from 12 to 16 years old, through an educational proposal based on a card game (built ad hoc) called "Fighting for my health", which was developed during the school breaks. This game was supplemented with the methodology of a healthy commitment, based mainly on the cooperative work between schools and families and the promotion of the responsibility among students about their health. Two groups were included (intervention and control), each one with a total number of 48 adolescents.

RESULTS

After the intervention, significant improvements were achieved in 5 of the 6 habits addressed (the exception was consumption of fried food) in the intervention group. Among them, it is necessary to highlight the significant difference (p < 0.001) obtained in breakfast and consumption of fruit between pretest and posttest and between pretest and retest. However, in the control group there were no significant differences in any of them.

CONCLUSION

A school-based intervention conducted from the Department of Physical Education, through healthy commitments using a card game, improved the feeding habits in adolescents.

Fitness, fatness and cardiovascular profile in South Spanish and North Moroccan women

INTRODUCTION

We studied the differences on physical fitness, fatness and cardiovascular profile in Spanish and Moroccan women.

MATERIAL AND METHODS

The study comprised 63 and 58 women aged 45-65 years from South of Spain and North of Morocco, respectively. We assessed fitness and body composition using standard procedures. We also assessed resting heart rate (RHR), blood pressure, fasting glucose, total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides.

RESULTS AND DISCUSSION

Moroccan women had a better performance in the main health-related physical fitness components, i.e. higher levels of cardiorespiratory fitness (P=0.01) and (lower-body) muscular strength (P<0.001). Diastolic blood pressure (P=0.004), RHR and total cholesterol (both P=0.04) were lower in Moroccan women. No differences were observed in the prevalence of metabolic syndrome.

CONCLUSIONS

The women from Morocco had a healthier fitness and cardiovascular profile than the women from Spain. Further research on physical fitness and other health indicators in understudied populations is needed.

Levels of plasma total adrenomedullin are related with two acute phase inflammatory reactants (fibrinogen and sialic acid) but not with markers of endothelial dysfunction in Type 1 diabetes Adrenomedullin and vascular risk factors in Type 1 DM

Adrenomedullin (AM), an ubiquitous regulatory peptide with different actions, is known to be elevated in different clinical situations, including diabetes mellitus (DM), but its potential role in the pathogenesis of diabetic vascular complications is not clear. In the present study, we examined plasma total AM levels, and their association with different markers of endothelial dysfunction and with other established risk factors for cardiovascular diseases, in patients with Type 1 DM. We studied a total of 155 patients, 117 patients without any kind of vascular complications, 24 patients with retinopathy only, and 14 patients with retinopathy and microalbuminuria but normal renal function. None of them had clinical evidence of atherosclerotic disease. Compared with the control group (64 healthy participants), patients had raised fibrinogen, soluble E-selectin ((s)E-selectin), vascular cellular adhesion molecule (VCAM), angiotensin converting enzyme (ACE), and von Willebrand factor (vWf) (P<.001 in all cases), but plasma total AM, endothelin (ET), sialic acid, and homocysteine were not raised. In the diabetic group, AM levels correlated significantly with sialic acid (r=.16; P<.05), but a more significant correlation was found with fibrinogen (r=.30; P<.001). No correlation was found with the other parameters studied. In summary, plasma total AM levels seem to correlate with inflammatory markers but not with endothelial dysfunction markers in Type 1 diabetic patients without atherosclerotic disease.

Public health surveillance and incidence of adulthood Guillain-Barré syndrome in Spain, 1998-1999: the view from a sentinel network of neurologists

Temporal variation in Guillain-Barré syndrome (GBS) warrants monitoring in certain situations. This study sought to describe a public-health-based GBS surveillance service in Spain and conduct pilot surveillance in the period 1998-1999. Neurologists from 11 hospitals countrywide, serving a population of 3.9 million, reported all patients, ages 20 years or over, admitted to hospital with suspected GBS. Cases that did not belong to the designated hospital catchment area or failed to fulfill diagnostic criteria after follow- up were excluded. Reported monthly incidence was compared against predicted incidence obtained from retrospective data (1985-1997) using a reported method based on 97.5% percentile values. Alarm thresholds for 2000 onwards were obtained by applying the same method to the updated 1985-1999 series. During the 2-year period, 98 GBS cases were reported, yielding an overall age-adjusted incidence of 1.26 per 100 000 population, with a breakdown by sex of 1.83 for males and 0.76 for females. Monthly incidence remained below or was similar to the corresponding threshold limit value. Seasonality with highest incidence in winter was more pronounced in the elderly. Preceding events, mainly respiratory infections, were identified in 71% of patients. Pilot two-year GBS surveillance in Spain resulted neither in alarm nor in preventive measures. Adult GBS incidence in Spain might be monitored by a surveillance system set up at short notice when a possible threat is perceived. A monthly incidence of over 3 per 100 000 person-years in the population aged 20 years or older would exceed threshold values.

[Nosocomial infection/colonization of the respiratory tract caused by Acinetobacter baumannii in an Internal Medicine ward]

BACKGROUND

To present the epidemiology of the outbreak and the description of patients with infection or colonization of the respiratory tract caused by A. baumannii in an Internal Medicine ward.

METHODS

20 consecutively patients hospitalized in the Internal Medicine ward were studied during 18 months with isolation of multiresistant A. baumanni in respiratory tract specimens with or without clinical signs of infection.

RESULTS

Starting on an index case, that was a patient coming from other hospital with diagnosis of nosocomial Acinetobacter pneumonia, we detected 20 patients. The age of the patients ranged from 48 to 95 years, with a mean of 71.4 years. Eighty percent were males. The clinical features were similar: advanced age, with chronic diseases (35 percent diabetics, 45 percent with chronic lung diseases), and use of broad-spectrum antibiotics agents, fundamentally third generation cephalosporin (70 percent), clarithromycin (55 percent) and quinolones (30 percent). 75 percent of patients were in the same ward. Eight (40 percent) of the patients with chronic lung diseases were subjects with COPD, two with asthma and chronic glucocorticoids treatment, and one with a sleep apnea. In four cases the isolation was considered a colonization. The mean stay was 26.15 days, and the mortality 40 percent.

CONCLUSIONS

The nosocomial infection caused by Acinetobacter baumannii is responsible of a high morbi-mortality between the patients hospitalized in an Internal Medicine ward, and produce an increase in length of stay. It is necessary a combination of control measures to prevent the transmission in the hospital and the outbreak of new multiresistant strains.

Zinc transformations in acidic soil and zinc efficiency on maize by adding six organic zinc complexes

Experiments under laboratory and greenhouse conditions were conducted to study the response of maize (Zea mays L.) to Zn fertilizer applications (Zn-phenolate, Zn-EDDHA, Zn-EDTA, Zn-lignosulfonate, Zn-polyflavonoid, and Zn-heptagluconate) in an Aquic Haploxeralf soil. The application of Zn complexes significantly increased Zn uptake by the plant compared with that in the control soil. The highest enhancements were obtained in soil treated with Zn-EDTA, Zn-lignosulfonate, and Zn-EDDHA. The highest percentages of Zn taken up by the plants occurred when 20 mg x kg(-1) Zn was applied as Zn-EDTA fertilizer and 10 mg x kg(-1) as Zn-lignosulfonate fertilizer. In the greenhouse experiment, Zn speciation in soil after harvesting showed that almost all Zn was found in the residual fraction followed by metal in the water-soluble plus exchangeable fraction and metal bound to organic matter. The most effective fertilizers maintaining Zn in the most labile fractions were Zn-phenolate, Zn-EDTA, and Zn-lignosulfonate. Conversely, in the incubation experiment, only a small percentage of Zn was found in the water-soluble plus exchangeable fraction and no differences in the Zn distribution were observed between the different fertilizer treatments. The micronutrient content in maize was positively correlated with the water-soluble plus exchangeable Zn as well as with the available Zn determined by the diethylenetriaminepentaacetic acid and Mehlich-3 methods, in the greenhouse experiment. Results of this study showed that the incubation experiment in acidic soil is not a suitable tool to establish the different effectiveness of Zn chelates in plants.

Guillain-Barré syndrome in Spain, 1985-1997: epidemiological and public health views

Retrospective demographic information and hospital record data were collected for 337 patients resident in Spain who had validated Guillain-Barré syndrome (GBS) diagnoses and clinical onset during the period 1985-1997 and had been admitted to 11 centres, covering a population of 3.9 million. The European age-adjusted GBS incidence per 100,000 for 1985-1997 among the population aged 20 and over was 0.85, with a breakdown of 1.14 in men and 0.58 in women. Incidence increased with age and time, with occasional rises that mimicked outbreaks and occurred at irregular 2- to 4-year intervals, mainly in winter. Spatial variation was modest. Respiratory and gastrointestinal infections respectively constituted 49.3 and 19.3% of recorded preceding events. The 97.5% intercentile limit, obtained from the 1985-1997 monthly incidences using predictions from a Poisson model, was proposed as the threshold value for pilot epidemiological surveillance of GBS in 1998-1999.

[Predictive factors for inappropriate hospital stays in an internal medicine department]

BACKGROUND

We aimed to know which factors are associated with inappropriate stays in an internal medicine department.

SUBJECTS AND METHOD

We included 1,046 hospitalisations and evaluated the justification of the admission using the Appropriateness Evaluation Protocol.

RESULTS

176 (16.8%) stays were considered inappropriate. In a multiple regression model, variables defining an inappropriate stay were the number of days in hospital, diagnosis on admission and the weekly day.

CONCLUSION

There are determining factors for inappropriate stays in an internal medicine department.

Adsorption and degradation of thiazopyr in compost-amended and non-amended soils

Adsorption and degradation of thiazopyr on two unamended soils and a soil amended annually during 8 years with compost were studied under laboratory conditions and compared with the results obtained on soils amended with fresh sewage sludge compost. The adsorption isotherms fitted the Freundlich equation well and a marked sorption increase was found in amended soils. Degradation data followed first-order kinetics and thiazopyr had a half-life of about 75 days at 25 degrees C and 60% water-holding capacity of soil. The addition of fresh compost markedly decreased the rate of thiazopyr degradation, whereas the compost mineralised in the field after annual additions had only a small influence. Incubation studies with sterile soils showed a very significant decrease of the degradation rate, indicating that degradation by micro-organisms was the main pathway of thiazopyr degradation in the soils studied.

[Factors associated with inappropriate hospitalization at an internal medicine department]

BACKGROUND

To determine the factors associated with inappropriate admissions in an Internal medicine department.

SUBJECTS AND METHOD

We included 1,993 admissions. The justification for the admissions was evaluated using the Appropriateness Evalutation Protocol.

RESULTS

187 (9.4%) admissions were considered inappropriate. The likelihood of an inappropriate admission was higher as long as the patient was younger than 65 years of age (OR, 1.94; (95%) IC, 1.32-2.85) and the admission had been programmed from the outpatients clinic (OR, 10.58; (95%) IC, 2.79-40.1). Clinical diagnosis also influenced the inappropriateness of admissions.

CONCLUSION

Age, diagnosis and source of patients determine inappropriate admissions in an internal medicine department.

[Factors that influence the non prescription of beta-blockers in patients with acute myocardial infarction]

OBJECTIVE

To study the factors that influence the non prescription of beta-blockers in patients discharged with a diagnosis of acute myocardial infarction (AMI).

METHOD

A retrospective study was done of all patients discharged from our Service in the year 1998, with a diagnosis of AMI. The variables considered were age, sex, diabetes mellitus, peripheral vascular disease, left ventricle dysfunction and COPD.

RESULTS

60 patients with AMI were included in the study, 18 of whom (30%) were discharged without beta-blockers. The average age of these patients was 77 years, while the average age of those discharged with these pharmaceutical agents was 60 years (p < 0.0001). Likewise, left ventricle dysfunction (p < 0.031) and female gender (p < 0.016), also negatively influenced the use of these drugs. It was observed with multivariable regression analysis that age was the main predictor for the use of beta-blockers (p < 0.0001).

CONCLUSION

Age is the main factor that influences the non prescription of beta-blockers in patients with AMI in our Service. In spite of the potential adverse effects of the drugs in the advanced age population, the data so far obtained demonstrates a clear benefit in the subgroups at risk (advanced age, heart failure,...). Therefore it's use should be extended to this group of population as long as there are no absolute contraindications.

Analysis of herbicide residues in cereals, fruits and vegetables

The determination of herbicide residues in cereals, fruits and vegetables by chromatographic methods is reviewed. The principal chemical groups of herbicides, like phenoxyacids, benzonitriles, ureas, triazines, dinitroanilines, chloroacetamides, carbamates, uracils, glyphosate and bipyridylium compounds, are considered. This review briefly provides some basic information on food sample extraction, clean-up, derivatization and determination of herbicide residues.

Use of antioxidants to treat pain in chronic pancreatitis

OBJECTIVE

The purpose of this report is to analyze the results of a 1-year clinical study of antioxidant therapy in the treatment of pain and recurrent inflammatory episodes in patients with chronic and acute recurrent pancreatitis, using a prospective, descriptive, pre-post, open design. The intensity of pain at the beginning and end of treatment was assessed with a visual analogue scale, and these results along with the number of hospital admissions for pancreatic disease were analyzed.

METHODS

We studied patients with acute recurrent or chronic pancreatitis who had suffered from pain or acute inflammatory episodes the year before the beginning of treatment with a complex containing L-methionine, beta-carotene, vitamin C, vitamin E and organic selenium.

RESULTS

Of 10 patients with chronic pancreatitis who completed treatment, the intensity of pain was reduced considerably in 9 (61.5 +/- 21.5 mm vs. 19.6 +/- 26.1 mm, p = 0.03), and pain was completely absent in 3 of these patients. Twelve patients who completed treatment had fewer hospital admissions during the year with antioxidant treatment than they had had during the previous year (1.5 +/- 1.62 vs. 0.25 +/- 0.45 admissions, p = 0.03).

CONCLUSIONS

Antioxidant treatment had a positive effect in patients who suffered from pancreatic inflammatory pain, and its effectiveness should be tested before more aggressive and costlier treatments are considered.

[Fibromuscular dysplasia with moyamoya phenomenon in a patient with Alport's syndrome. A type IV collagen disorder]

INTRODUCTION

Alport's syndrome is a hereditary progressive nephropathy associated with neurosensorial deafness, secondary to mutations of the genes which codify the a chains of collagen IV. In the literature we have found isolated reports of cases with nervous system involvement.

CLINICAL CASE

A 37 year old woman was diagnosed as having Alport's syndrome with terminal secondary chronic renal failure and bilateral neurosensorial deafness. She was assessed following repeated transient ischemic attacks of the left hemisphere over the previous three years. Neurological examination was normal. Magnetic resonance showed an ischemic stroke of the left frontal white matter, and on arteriography there was tubular stenosis of the left extracranial internal carotid artery and proximal occlusion of the homolateral anterior and medial cerebral arteries with a compensatory deep vascular network, compatible with fibromuscular dysplasia and secondary moyamoya phenomenon.

CONCLUSIONS

Although the association between fibromuscular dysplasia and Alport's syndrome may be casual, we suggest that there may be a common mechanism of pathogenesis in both syndromes, related to the expression of type IV collagen in the vascular basal membranes.

[Subdural empyema due to Mycoplasma hominis following epidural anesthesia]

INTRODUCTION

In the literature there are sporadic reports of spinal epidural abscesses after epidural anaesthesia (Staphylococcus aureus in 82%), whilst subdural empyemas are more often related to ear and sinus conditions.

CLINICAL CASE

A 32 year old woman with a clinical history of migraine and symmetrical frontal atrophy on a previous cerebral CT scan, after Caesarean section under epidural anaesthesia, presented with orthostatic headache two days later. On the fourth day it had become constant and she had a high temperature which was considered to be caused by infection of the surgical wound. Neurological examination was found to be normal, the CT scan was inconclusive and the CSF showed a lymphocytic pleocytosis without consumption of glucose. In view of her worsening clinical condition on the ninth day, in the absence of a cutaneous focus and on suspicion of a para-meningeal infective focus, lumbar MR was done and found to be normal, and cerebral MR which showed images compatible with a right fronto-parietal subdural empyema. After a parietal craniotomy and culture of the surgical specimen, colonies of Mycoplasma hominis were grown, similar to those grown from the exudates of the abdomical surgical wound. Treatment was started with ciprofloxacine.

CONCLUSION

We consider that following epidural anaesthesia the patient developed hypotension of the CSF with a secondary subdural hematoma or hygroma and this became infected by hematogenous spread of Mycoplasma hominis.

[Genotype-phenotype correlation in myotonic dystrophy and prediction of clinical seriousness]

INTRODUCTION

Since description of the expansion of the number of CTG trinucleotides on the long arm of chromosome 19 in the 19 q 13.2-13.3 interval as being responsible for myotonic dystrophy (DM), many studies have established a direct relationship between the size of the expansion and the severity of the manifestations.

OBJECTIVES

To evaluate the clinico-genetic correlation in a population with DM in Eastern Andalucia and to establish the predictive value of the increase in number of CTG repetitions with regard to clinical gravity.

PATIENTS AND METHODS

A transverse study of persons from families known to have members with DM, classified with regard to the clinical gravity of their illness. Diagnosis was by means of clinical neurological, ophthalmological and neurophysiological examination and subsequently by genetico-molecular study, Southern blot, PCR, oligonucleotide CTC hybridization and Northern blot.

RESULTS

Genetic studies confirmed the previous clinical diagnosis of DM in 78 persons, of the 145 studied, who came from 32 families. The average size of the mutation was 1-5 kb. There was close correlation between the size of the expansion and the clinical condition. Logistic repression studies permitted adequate classification in function of the size of the expansion in 87.23% of the cases of clinically relevant illness and in 90% of the cases in which the condition was not clinically relevant.

CONCLUSIONS

There is a strong association between the clinical features of DM and the magnitude of the mutation. The size of the expansion has considerable predictive value in prognosis of the disorder. This may be useful when making decisions during prenatal diagnosis.

[What do the internal medicine residents of Anadalusia think of their specialty? Survey results]

BACKGROUND

To know the opinion of andalusian Internal Medicine (IM) residents about different subjects of their specialty, and their biomedical investigation activities.

PATIENTS AND METHODS

A questionnaire with codified answers, facilitated to 64 IM residents of Andalusia.

RESULTS

69% of residents referred that IM was the specialty they wished to adhere at first choice. A 61% of residents would advice choosing IM as specialty to physicians with the exams for becoming a resident just passed. Best merit of IM for 89% of people was the global sight of the patient, and worst one for 37.5% was its tendency to fragmentation. 47% of residents consider that the role of the specialty will grow in the future.

CONCLUSIONS

Our questionnaire reflects some of the contradictions that IM as a specialty is living, and probably show the rely of future internists to some future propositions about the specialty.

[Perioperative response of phosphorus and calcium metabolism and of bone remodeling markers during heart surgery under extracorporeal circulation]

HYPOTHESIS AND OBJECTIVES

Cardiovascular surgery with extracorporeal circulation (ECC) is highly stressful, inducing marked changes in calcium and magnesium homeostasis. Nevertheless, no studies have assessed osteoblastic/osteoclastic activity during and after heart surgery with ECC. Our objective was to analyze changes in serum levels of parameters reflecting phosphorus and calcium metabolism and markers of bone remodelling in this context.

PATIENTS AND METHODS

Changes in serum levels of calcium, phosphorus, whole parathyroid hormone (PTH), magnesium, cortisol, interleukin-6, total alkaline phosphatase, osseous alkaline phosphatase (OAP), osteocalcin, propeptide of type 1 procollagen (PCP1), and carboxyl-terminal telopeptide of type 1 collagen (CTT1) during the 24 perioperative hours in 16 patients undergoing cardiac surgery with ECC.

RESULTS

Total calcium decreased during ECC, triggering acute release of PTH. Osteocalcin decreased at 24 hours in a way that was not accounted for by hemodilution. OAP changes, on the other hand, were consistent with albumin levels and blood cell counts. PCP1 and CTT1 did not change, although correcting for dilution shows that these factors can in fact be considered to have increased.

CONCLUSIONS

The parathyroid gland is activated during ECC. Markers of bone metabolism behave differently over time in response to heart surgery. The data suggest that heart surgery induces discordant responses in various bone cell functions.

Simultaneous determination of the colorants tartrazine, ponceau 4R and sunset yellow FCF in foodstuffs by solid phase spectrophotometry using partial least squares multivariate calibration

A method is proposed for the simultaneous determination of the colorants tartrazine (TT), sunset yellow FCF (SY) and ponceau 4R (PR) in foods. The colorants were fixed in Sephadex DEAE A-25 gel at pH 2.0 and then packed in a 1-mm silica cell. The spectra of the analytes fixed in the solid support were recorded between 400 and 800 nm against a blank and the partial least squares (PLS) multivariate calibration was used to obtain the results. The linear dynamic ranges of the calibration graphs were from 50.0 to 650.0 ng ml(-1) for the three colorants and these ranges were taking in account the optimisation of the calibration matrix using the PLS-1 algorithm. The experimental results showed that the optimum number of factors for the calibration matrix was four in all instances and the residual means standard deviation was 5.5267 for SY, 6.3878 for TT and 6.9816 for PR. The square of the correlation coefficients were 0.9977, 0.9978 and 0.9954 for SY, TT and PR respectively. The method was applied to the determination of the colorants in foods and results were compared with those obtained by means of HPLC as reference method. The results obtained can be considered as acceptable in most cases (eight of nine commercial samples). The relative standard deviations ranging between 0.5 and 10.8 for the commercial samples analysed.

[The clinical and evolutional characteristics of visceral leishmaniasis in patients with HIV infection]

OBJECTIVE

To analyze the clinical features, yield of the diagnostic techniques, and therapeutic response of HIV-associated visceral leishmaniasis (VL), and compare the initial episodes to the relapses.

METHODS

Forty-one episodes of leishmaniasis visceral, diagnosed in 31 HIV-positive patients between 1st February 1992 and 31st January 1996 were reviewed.

RESULTS

The prevalence of VL in HIV-positive patients in our center was 4.2%. Fifty-eight percent of the patients had AIDS prior to the diagnosis of VL. Fever was more frequent in the initial episodes than in the relapses (90.3% versus 60%; p < 0.05; OR: 6.2; IC 95%: 0.8-51.5), splenomegaly was more frequent in the relapses (100% versus 71%; p = 0.05). The diagnostic delay was longer in the initial episodes (27.2 +/- 22.7 versus 5 +/- 4.8 days; p < 0.05). The diagnostic yield of bone marrow biopsy was 82.1%, of liver biopsy 72.7% and of splenic fine-needle aspiration 87.5%. The indirect immunofluorescence test for Leishmania antibodies was positive in 5.9% of cases. Therapeutic failure occurred in 47.6% of patients treated with antimonials and 3.3% of patients treated with amphotericin B. Those patients who received secondary prophylaxis had less relapses than those who did not (17.6% versus 66.7%; p < 0.05; OR: 0.11; IC 95%: 0.01-1.28). Of the 31 patients, twenty-six (83.8%) died, and in none of them was the cause of the death directly related to LV.

CONCLUSION

HIV-associated VL manifests clinically in a similar fashion to the immunocompetent's disease. It appears in advanced immunosuppression phases, behaving like other AIDS-defining illnesses. In spite of a good therapeutic response the relapse rate is high.

Simultaneous determination of the colorants sunset yellow FCF and quinoline yellow by solid-phase spectrophotometry using partial least squares multivariate calibration

A method for the simultaneous determination of the colorants Sunset Yellow FCF and Quinoline Yellow using solid-phase spectrophotometry is proposed. The colorants were isolated in Sephadex DEAE A-25 gel at pH 5.0, the gel-colorants system was packed in a 1 mm silica cell and spectra were recorded between 400 and 600 nm against a blank. Statistical results were obtained by partial least squares (PLS) multivariate calibration. The optimized matrix by using the PLS-2 method enables the determination of the colorants in artificial mixtures and commercial soft drinks.

CD50 (intercellular adhesion molecule-3) is expressed at higher levels on memory than on naive human T cells but induces a similar calcium mobilization on both subsets

CD50, the intercellular adhesion molecule-3 (ICAM-3), is expressed almost exclusively on hematopoietic cells. T lymphocytes display a bimodal distribution on CD50 expression levels. It was observed that CD45RO+ cells expressed higher levels of CD50 than CD45RA+ T lymphocytes. A similar situation was observed when CD4 and CD8 subpopulations were analyzed, with CD8+ cells expressing higher levels of CD50 than CD4+ cells. When adult T lymphocytes were analyzed by three-color flow cytometry in CD8+CD45RA+ cells both CD50low and CD50high expressing cells were detected, in accordance with several memory markers on T lymphocytes, whereas only cells with a low level of CD50 were observed in CD4+CD45RA+. The different level of CD50 expression was confirmed by analyzing purified CD45RA+ and CD45RO+ T cells. Moreover, after the comparison of CD50 expression level in thymocytes, cord blood and adult T lymphocytes, a progressive increase was observed. When T cells were sorted by their intensity of CD50 expression, only CD50high cells proliferated in response to tetanus toxoid. Therefore, the phenotypic and functional analysis of adult and cord blood T lymphocytes as well as thymocytes indicates that CD50 expression increases during the maturation process of T lymphocytes: from the lowest CD50 levels present on CD1+ thymocytes, to the highest levels of CD50 on human memory T cells. In addition, we have observed that after CD50 cross-linking on human T lymphocytes, a transient increase in intracellular calcium concentration ([Ca2+]i) is produced. When CD45RA+ and CD45RO+ T cells were analyzed, in spite of the level of CD50 expression, the stimulation through CD50 induced a similar level of Ca2+ mobilization in both subpopulations, contrasting with the higher rise in [Ca2+]i induced by CD3 stimulation on CD45RA+ versus CD45RO+. These data suggest that the signal transduction pathways activated after CD50 cross-linking are, at least partially, independent of those involved after CD3 stimulation.

[The Short-Form impairment index (SFII) in schizophrenic patients]

The SFII (Short-Form Impairment Index, Horton and cols, 1986) was used to assess cognitive impairment in patients with DSM-III-R diagnosis of schizophrenia and its relationship to the positive and negative schizophrenic symptoms was studied. Two samples of DSM-III-R schizophrenic patients were studied. The first sample was composed of 30 consecutively inpatients admitted by recrudescence of their symptoms. The second was composed of 19 patients that were attending to a Day Psychiatric Hospital by recrudescence of their symptoms or by socio-familiar dysfunctions. The SFII included three subtest: the "Trail Making" Form B, and cubes and digit symbol from the WAIS, that were converted to typical scores adjusted to age (Reitan, 1973). The positive and negative schizophrenic symptoms were assessed by the Andreasen scales (SAPS y SANS). No differences in epidemiological variables were found between both samples. Higher cognitive impairment (lower SFII) and higher negative symptoms were significantly correlated in both samples. This result suggests that the SFII could be a good marker of cognitive functioning in schizophrenic patients in postacute samples and also in mixed schizophrenic patients (acute and defectual population). The SFII presented some limitations in our young samples derived from their age-corrected values.

IL-4 inhibits IL-2 synthesis and IL-2-induced up-regulation of IL-2R alpha but not IL-2R beta chain in CD4+ human T cells

There is growing evidence to suggest a regulatory role of IL-4 in the immune system affecting both proliferation and lymphokine production. In the present work we have analyzed the effect of IL-4 on IL-2 and IFN-gamma synthesis by stimulating CD4+ human T cells (+10% accessory cells) with Con A in the presence of several doses (1 to 100 U/ml) of human rIL-4. The results showed an impaired IL-2 and IFN-gamma synthesis in the presence of IL-4. This inhibition was dose dependent and was evident only when IL-4 was added in the first 2 h of culture. Moreover, the external addition of IL-2 did not revert the inhibitory effect of IL-4 on IL-2 and IFN-gamma synthesis induced by Con A. We have also analyzed the effect of IL-4 on the expression of both alpha- and beta-chains of the IL-2R. Although the expression of IL-2R alpha mRNA was not modified after 6 h in culture in the presence of IL-4, a decrease was observed at 24 and 48 h. The addition of rIL-2 showed that the inhibition in IL-2R alpha expression could be explained by an impairment in the up-regulatory signal transmitted through the IL-2R. In addition to this, IL-4 did not modify the IL-2R beta mRNA expression at 6 and 24 h although a decreased expression was observed at 48 h which could be explained by the defective IL-2 production. The differential effect of IL-4 on the up-regulatory effect of IL-2 in the expression of IL-2R alpha and IL-2R beta suggest the existence of different regulatory mechanisms acting on the expression of both chains.

IL-4 inhibits IL-2 synthesis and IL-2-induced up-regulation of IL-2R alpha but not IL-2R beta chain in CD4+ human T cells

There is growing evidence to suggest a regulatory role of IL-4 in the immune system affecting both proliferation and lymphokine production. In the present work we have analyzed the effect of IL-4 on IL-2 and IFN-gamma synthesis by stimulating CD4+ human T cells (+10% accessory cells) with Con A in the presence of several doses (1 to 100 U/ml) of human rIL-4. The results showed an impaired IL-2 and IFN-gamma synthesis in the presence of IL-4. This inhibition was dose dependent and was evident only when IL-4 was added in the first 2 h of culture. Moreover, the external addition of IL-2 did not revert the inhibitory effect of IL-4 on IL-2 and IFN-gamma synthesis induced by Con A. We have also analyzed the effect of IL-4 on the expression of both alpha- and beta-chains of the IL-2R. Although the expression of IL-2R alpha mRNA was not modified after 6 h in culture in the presence of IL-4, a decrease was observed at 24 and 48 h. The addition of rIL-2 showed that the inhibition in IL-2R alpha expression could be explained by an impairment in the up-regulatory signal transmitted through the IL-2R. In addition to this, IL-4 did not modify the IL-2R beta mRNA expression at 6 and 24 h although a decreased expression was observed at 48 h which could be explained by the defective IL-2 production. The differential effect of IL-4 on the up-regulatory effect of IL-2 in the expression of IL-2R alpha and IL-2R beta suggest the existence of different regulatory mechanisms acting on the expression of both chains.

[Radioimmunoanalysis of plasma testosterone]

A simple radioimmunoassay procedure for the determination of testosterone concentration in plasma is described. Small amounts of plasma, 0,5 ml for males and 1 ml for females, are extracted with diethyl ether. Recoveries for the extraction are obtained by the addition of labelled tesosterone. The radioimmunoassay is performed directly on the extracts without further purification. Separation of the free from the antibodie bound testosterone is achieved with dextran coated charocoal. Under the used conditions, the calibration curve covers a range between 0,5 and 1,5 ng per sample. Reproducibility is acceptable with a coefficient of variation of 7%. The normal values are slightly higher than those obtained with methods using some purification step of the extract before the assay but due to its simplicity the described method is a suitable one for clinical purposes.