Molecular biology of neuroblastoma

Neuroblastoma is one of the most frequently occurring solid tumours in children, especially in the first year of life, when it accounts for 50% of all tumours. It is the second most common cause of death in children, only preceded by accidents. The most peculiar characteristic of neuroblastoma is its clinical heterogeneity. Approximately half of the cases are classified as high risk, with overall survival rates around 40% despite intensive multimodal therapy. Nevertheless, other subsets of neuroblastomas will undergo spontaneous regression and others will show very slow progression. Despite many advances in the past three decades, neuroblastoma has remained an enigmatic challenge to clinical and basic scientists. Elucidation of the exact molecular pathways of neuroblastoma will enable researchers and clinicians to stratify the disease and adapt therapy to the risk of relapse or progression. This review focuses on recent advances in our understanding of the biology of this complex paediatric tumour. Neuroblastoma is already one of the first examples for the use of tumoral genetic markers as a tool for defining tumour behaviour and to aid clinical staging.

Secondary effluent reclamation: combination of pre-treatment and disinfection technologies

A study was carried out to evaluate the efficiency of secondary effluent additional treatment, using a combination of pre-treatments (ring filter, physico-chemical and infiltration-percolation) followed by disinfection methods (chlorine dioxide, peracetic acid and ultraviolet light). Three different indicator microorganisms were determined: E. coli, total coliforms and somatic bacteriophages. The results show better efficiency of physico-chemical and infiltration-percolation processes. Bacteriophages were eliminated to a lesser extent than bacterial indicators in all the treatment systems. Chlorine dioxide and peracetic acid seems to be more efficient in disinfection than ultraviolet light when a ring filter is the pre-treatment used. For the same doses and contact times, the efficiency of the disinfection methods is higher when the pre-treatment used is the physico-chemical or the infiltration-percolation system. The final effluent quality from the physico-chemical treatment train and the infiltration-percolation treatment train, followed by the disinfectants, achieves an E. coli content that allows the reuse in most of the uses described in the Spanish legislation for wastewater reuse.

Differential effects of phenylalanine ammonia lyase, cinnamyl alcohol dehydrogenase, and energetic metabolism inhibition on resistance of appropriate host and nonhost cereal-rust interactions

ABSTRACT Effects of phenylpropanoid and energetic metabolism inhibition on resistance were studied during appropriate host and nonhost cereal-rust interactions. In the appropriate barley-Puccinia hordei interaction, phenylalanine ammonia lyase (PAL) and cinnamyl alcohol dehydrogenase (CAD) inhibition reduced penetration resistance in two genotypes, suggesting a role for phenolics and lignins in resistance. Interestingly, penetration resistance of the barley genotype 17.5.16 was not affected by phenylpropanoid biosynthesis but penetration resistance was almost completely inhibited by D-mannose, which reduces the energy available in plant host cells. This suggests a parallel in the cellular basis of penetration resistance between 17.5.16 rust and mlo barleys powdery mildew interaction. Results revealed differing patterns of programmed cell death (PCD) in appropriate versus nonhost rust interactions. PAL and CAD inhibitors reduced PCD (hypersensitivity) in appropriate interactions. Conversely, they had no effect in PCD of wheat to P. hordei; whereas D-mannose dramatically reduced nonhost resistance and allowed colony establishment. The differential effects of inhibitors in the expression of the different resistances and the commonalities with the cereal-powdery mildew interaction is analyzed and discussed.

Genotypes of the C677T and A1298C polymorphisms of the MTHFR gene as a cause of human spontaneous embryo loss

BACKGROUND Polymorphisms C677T and A1298C of the MTHFR gene have been implicated in fetal viability. In this study, we determined the allele and genotype frequencies of these polymorphisms in different populations, including spontaneous abortion (SA) fetal tissues, with the objective of evaluating their impact on fetal viability. METHODS 342 samples of fetal tissues, selected from SA occurring during the 1980s, 230 samples from subjects born in the 1980s and a third set of samples from 204 subjects born in the 1950s, were genotyped by using TaqMan probes. RESULTS The wild CC genotype of the C677T polymorphism showed a strong protective effect against abortion (0.03 in SA versus 0.47 in 1950s and 0.43 in 1980s) (P < 0.0001). Genotypes of three mutations in the combinations of polymorphisms for C677T and A1298C showed a very low frequency in the living population; however, the three mutations genotypes were over expressed in the SA group (0.02 in 1950s; 0.03 in 1980s and 0.17 in SA) (P < 0.0001). Samples with four mutations (n = 2) were found only in the SA group. CONCLUSIONS There is no linkage disequilibrium between C667T and A1298C polymorphisms. Fetal viability is directly related to the CC genotype as a protector while the three and four mutation MTHFR genotypes appear to be a determinant on fetal non-viability and SA.

Radiologic evaluation of the cement mantle in the femoral shaft. A comparative study using a fast-set or a standard-set cement

INTRODUCTION

At present a wide spectrum of cement types are available for cemented total hip arthroplasty (CTHA). All types have the same objective, i.e. to prolong the life of the implant for as long as possible. The purpose of this study was to compare the radiologic cement mantle of CTHA using cement with fast or standard setting characteristics.

METHOD

A prospective comparative study of patients who underwent CTHA was performed: the first group received fast setting cement (Cemex System Fast), the second group received standard setting cement (Cemex System). A radiologic evaluation of the cement mantle was done using Barrack's classification. In order to give the study clinical relevance we assembled Barrack's classification in two groups: 1) Low risk group (Types A and B); 2) High risk group (Types C and D). According to ISO 5833:2002, the international standard was used to perform physico-chemical (polymerization temperature, setting time) and mechanical testing (compression strength, bending strength and bending modulus).

RESULTS

The fast setting cement showed a shorter setting time and a higher polymerization temperature. The mechanical performances of both cements met the ISO limits. At a mean follow-up of 23 months (11-37 months) no statistically significant radiological difference was found in the radiologic cement mantle between the two groups either in the post-operative X-ray evaluation (p=0.32) or in the last follow-up (p=0.72). Statistical evaluation was done comparing the two sub-groups, i.e. low risk and high risk.

CONCLUSIONS

The use of fast or standard setting cement does not produce any difference in the quality of the radiologic cement mantle in the short-term. Both cements comply with ISO 5833 requirements.

Evaluation of the triangular fibrocartilage in cadaveric wrists by means of arthrography, magnetic resonance (MR) imaging, and MR arthrography

PURPOSE

To evaluate the diagnostic accuracy of arthrography, magnetic resonance (MR) imaging, and MR arthrography in the detection and localization of defects of the triangular fibrocartilage (TFC) in cadaveric wrists, using arthroscopy as a reference standard.

MATERIAL AND METHODS

Twenty-four specimen wrists were evaluated. The different imaging modalities were blinded to reviewers and were interpreted independently. A classification of TFC defects was used for the evaluation of images in the different imaging modalities, thus permitting a more uniform correlation. Two cases were excluded from the MR imaging study because of poor image quality. Contingency tables with the chi-square test and Fisher's exact test were used for statistical analysis.

RESULTS

Defects of the TFC were identified in 17 of the 24 specimen wrists by means of arthroscopy, and 16 defects were observed when arthrography was carried out. With MR imaging 14 defects of the TFC were detected in the 22 specimen wrists evaluated, and with MR arthrography 16 defects were observed. Most defects were central or combined (two or more defects). In comparison to arthroscopy, the accepted diagnostic gold standard, the following results were found for arthrography in the detection of TFC defects: sensitivity 95%, specificity 100%, and accuracy 95% (P<0.0005); for MR imaging: sensitivity 86%, specificity 85%, and accuracy 70% (P<0.002); and for MR arthrography: sensitivity 100%, specificity 85%, and accuracy 95% (P<0.0005).

CONCLUSION

The results of the study seem to indicate that both arthrography and MR arthrography have high accuracy, and either would be useful for evaluation of the TFC. The combined approach using both techniques would have a very high accuracy equivalent to that resulting from arthroscopy.

Catalytic wet peroxidation of phenol in a fixed bed reactor

Iron-containing mesostructured materials (Fe-SBA-15) are suitable for continuous treatment of phenolic aqueous solutions by means of catalytic wet peroxide oxidation (CWPO) in a packed-bed reactor. These materials were successfully extruded, crushed and sieved with a particle size ranging from 1 to 1.6 mm using mineral clay and methyl cellulose as binders. Non-significant changes have been found in the textural and structural properties of the extruded material in comparison to the parent powder Fe-SBA-15 material. Activity of extruded catalyst in terms of phenol degradation and TOC reduction has been monitored in a continuous mode. The increase of residence time enhances significantly the TOC degradation. The catalyst stability, taking into account the loss of iron species from the catalyst into the aqueous solution, has also been examined. The catalytic results of Fe-SBA-15 material in comparison to a homogeneous catalytic test prove the relevant role of the solid catalyst in the oxidation process.

[Cranial wounds of the skull caused by a fencing-foil]

Penetrating stab cranial wounds of the skull by fencing-foil are rare in western countries.

CASE REPORT

This 46-year-old man suffered a penetrating stab wound of the skull through the right orbital region. As a consequence he developed an intracranial hematoma requiring surgical evacuation.

DISCUSSION AND CONCLUSIONS

Damage of intracranial contents due to transorbital penetrating objects other than missiles is a rare event.

Perioperative intravenous iron preserves iron stores and may hasten the recovery from post-operative anaemia after knee replacement surgery

In unilateral total knee replacement (TKR), perioperative blood loss, low transfusion thresholds and short hospital stay result in patients being discharged with low haemoglobin (Hb). We assessed the effects of perioperative administration of intravenous iron, with or without erythropoietin, plus a restrictive transfusion threshold (Hb < 80 g L(-1)) both on transfusion rate and recovery from post-operative anaemia. TRK patients received iron sucrose (2 x 200 mg per 48 h, iv) (Group IVI, n = 129). Patients with admission Hb < 130 g L(-1), also received erythropoietin (1 x 40 000 IU, sc) (Group EPO, n = 19). Perioperative clinical and laboratory data were obtained. Mean Hb loss was 36 g L(-1), but only seven patients were transfused (5%). Pre-operatively, 66 (45%) patients did not have enough stored iron to compensate Hb loss. At post-operative day 30, only 15% were anaemic, 70% of Hb loss and 92% of pre-operative Hb were recovered and ferritin increased by 73 microg L(-1) (P < 0.01), although erythropoietic response was higher in patients receiving erythropoietin (P < 0.05). No adverse effects of iron sucrose or erythropoietin were witnessed. This protocol seems to reduce allogeneic blood transfusion rate and may hasten the recovery from post-operative anaemia in TKR patients, without depleting iron stores. Further studies are needed to ascertain which patients may benefit of extended intravenous iron and/or erythropoietin administration.

A simple technique for shoulder arthrography

PURPOSE

To present a systematic approach to teaching a technique for arthrography of the shoulder. Using an adhesive marker-plate with radiopaque coordinates, precise sites for puncture can be identified and the need for fluoroscopic guidance obviated.

MATERIAL AND METHODS

Forty-six glenohumeral arthrograms were performed in 45 patients; in 1 case involving examination of both shoulders. The stages of the technique are described in detail, as are the fundamental aspects of achieving an effective glenohumeral injection. Pain intensity was measured in all patients using a verbal description scale.

RESULTS

Shoulder arthrography was successful in all cases. Average time taken for the procedure was 7 min, with no difference in the respective times required by an experienced radiologist and a resident. The procedure was well tolerated by most patients, with slight discomfort being observed in a very few cases.

CONCLUSION

The arthrographic technique used in this study is simple, safe, rapid, and reproducible, and has the advantage of precise localization of the site for puncture without need for fluoroscopic guidance. The procedure described in this study can be of help in teaching residents and can reduce the learning curve for radiologists with no experience in arthrographic methods. It also reduces the time of exposure to fluoroscopy.

A prospective trial comparing oocyte donor ovarian response and recipient pregnancy rates between suppression with gonadotrophin-releasing hormone agonist (GnRHa) alone and dual suppression with a contraceptive vaginal ring and GnRH

BACKGROUND

Contraceptive treatment before gonadotrophin-releasing hormone agonist administration presents advantages in women with a tendency to hyper-response and simplifies donor-recipient treatment synchronization. This study compares response to gonadotrophin stimulation under hypophyseal suppression in oocyte donors with or without vaginal contraceptive pretreatment.

METHODS

One hundred and ninety oocyte donors were recruited in a single centre and prospectively assigned to one of two treatment groups, according to the day of the week menstruation initiated: Group VC-, no prior vaginal contraceptive and Group VC+, prior vaginal contraceptive.

RESULTS

VC+ patients presented a significantly higher cancellation rate, lower plasma estradiol levels and fewer follicles >12 mm on the day of hCG, versus the VC- group. Number of oocytes recovered was significantly lower in the VC+ group. All the cases of severe ovarian hyperstimulation syndrome (SOHSS) were in the VC- group. Pregnancy rates by embryo transfer to synchronic recipients were similar between VC+ and VC- (59.5 versus 57.9%, respectively).

CONCLUSIONS

Vaginal contraceptive pretreatment resulted in a higher ovarian suppression, whereas SOHSS rate was lower than in donors who did not receive pretreatment. There were no differences in pregnancy rates between the two groups of synchronic oocyte recipients.

Recombinant X chromosome in a prenatal diagnosis

The prenatal cytogenetic study of an amniotic fluid sample of a 39-year-old female showed one X chromosome with a fragment of extra material in the short arm. The G-band pattern suggested that the extra material could be the long arm of an X chromosome. Several complementary studies were performed in order to better clarify the origin of the material. These studies included parental karyotypes, microsatellite typing and comparative genomic hybridization (CGH). The results obtained allowed us to conclude that the derivative chromosome arose de novo as a recombinant X chromosome with duplication of Xq and partial deletion of Xp. Once informed, the parents decided to continue with the pregnancy, after which a healthy girl was born with no apparent disorders.

Heavy metal speciation and phytotoxic effects of three representative sewage sludges for agricultural uses

The environmental impact of sewage sludges depends on the availability and phytotoxicity of their heavy metal. The influence of representative sludges (dewatered anaerobic, pelletization, and composted sludge) on the availability of heavy metals, and their effects on seed germination were compared. The total heavy metal concentrations were below the maximum permitted for land-applied waste and the differences among them were small. The DTPA-extracted metal concentrations were rather different. The sequential extraction of the compost showed a slight increase in Cd and Cu availability, and a decrease in the availability of Fe, Mn, Ni and Zn. Pelletization increased the availability of Ni and slightly reduced that of Cr. The dewatering sludge led to greater availability of Cr and Mn but reduced the concentration of Cd. The three different sludges also affected seed germination and root elongation in different ways. The most serious adverse effects were caused by the dewatered sludge extract.

Donor age and degree of HLA matching have a major impact on the outcome of unrelated donor haematopoietic cell transplantation for chronic myeloid leukaemia

We analysed the outcome of 92 consecutive unrelated donor haematopoietic cell transplantations (UD-HCTs) performed in Spain to treat adult patients with CML in the first chronic phase (1CP). Patients' and donors' median age was 32 (15-49) and 36 (22-56) years, respectively. In all, 73 pairs (79%) matched for A, B+/-C and DRB1+/-DQB1 loci and 19 had > or =1 mismatch. Their probability of survival and disease-free survival at 4 years were 50 and 46%, respectively. Pretransplant factors associated with a better survival were patient age <25 years (P=0.035), donor age < or =36 years (P=0.012), use of cyclosporine since day -7 (P=0.001), and matching 8/8, 9/10 or 10/10 loci at allele level (P=0.003). In multivariate analysis only donor age (P=0.003; RR=3.1 (95% CI: 1.3-7.1)) and degree of HLA-matching (P=0.009; RR: 7.7 (95% CI: 1.8-33)) maintained their significance. The addition of these two variables to the EBMT prognostic score allowed an adequate risk assessment for patients receiving a UD-HCT during 1CP. Our analysis shows that in patients with a young and fully allele-matched donor, UD-HCT should be considered in the initial therapeutic algorithm due to its excellent outcome (92% survival at 2 years).

[Anesthetic management for thoracoscopic repair of type I esophageal atresia with continuous-flow single-lung ventilation]

We describe a continuous flow mode of ventilation for repair of type I esophageal atresia in an infant. This type of atresia is defined by distal stenosis of the esophagus with a proximal blind pouch and no connection to the tracheobronchial tree. In traditional repair procedures the surgical approach is by thoracotomy, but newer videoassisted thoracoscopic techniques have introduced novel challenges to ventilatory mechanics in these low-weight infants. The literature contains little discussion of the anesthetic management or respiratory mechanics of these patients. Trying to maintain adequate tidal volume and oxygenation while thoracoscopic maneuvers take place increases the risk of barotrauma. Single-lung ventilation with a continuous flow respirator was effective in the case we report.

The treatment of mice with Lactobacillus casei induces protection against Babesia microti infection

In this study, we report that administration of Lactobacillus casei confers protection to mice against the intracellular protozoan Babesia microti. Mice treated with L. casei orally or intraperitoneally were inoculated 7 days later with an infectious dose of B. microti. Mice treated with lactobacilli showed significant reduction in the percentage of parasitized erythrocytes (PPE) compared to untreated mice. When mice were inoculated intraperitoneally with L. casei 3 or 0 days before challenge with B. microti, the PPE was significantly lower compared to untreated mice and there were no differences between treated mice and mice immune to B. microti infection. When mice treated with live or dead L. casei were compared to mice inoculated with Freund Complete Adjuvant before a B. microti infection, a significant reduction of PPE was observed. These results show the protective effect of L. casei administered to mice against a B. microti infection and suggest that it might act by stimulating the innate immune system.

Mortality in Spain during the heat waves of summer 2003

The effect of the elevated temperatures on mortality experienced in Europe during the summer of 2003 was observed in several countries. This study, carried out in Spain, describes mortality between 1 June and 31 August and evaluates the effect of the heat wave on mortality. Observed deaths were obtained from official death registers from 50 provincial capitals. Observed deaths were compared with the expected number, estimated by applying a Poisson regression model to historical mortality series and adjusting for the upward trend and seasonality observed. Meteorological information was provided by the Instituto Nacional de Meteorologia (National Institute of Meteorology). Spain experienced three heat waves in 2003. The total associated excess deaths were 8% (43 212 observed deaths compared with 40 046 expected deaths). Excess deaths were only observed in those aged 75 years and over (15% more deaths than expected for the age group 75 to 84 and 29% for those aged 85 or over). This phenomenon (heat-associated excess mortality) is an emerging public health problem because of its increasing attributable risk, the aging of the Spanish population and its forecasted increasing frequency due to global warming. The implementation of alert and response systems based on monitoring of climate-related risks, emergency room activity and mortality, and strengthening the response capacity of the social and health services should be considered.

Perioperative stimulation of erythropoiesis with intravenous iron and erythropoietin reduces transfusion requirements in patients with hip fracture. A prospective observational study

BACKGROUND AND OBJECTIVES

Patients undergoing surgery for hip fracture (HF) often receive perioperative allogeneic blood transfusions (ABT) to avoid anaemia. However, concerns about the adverse effects of ABT have prompted the review of transfusion practice and the search for a safer treatment of perioperative anaemia.

MATERIALS AND METHODS

We prospectively investigated the effect of a blood-saving protocol of perioperative iron sucrose (3 x 200 mg/48 h, intravenously) plus erythropoietin (1 x 40,000 IU, subcutaneously) if admission haemoglobin level < 130 g/l, on transfusion requirements and postoperative morbid-mortality in patients with HF (group 2; n= 83). A parallel series of 41 HF patients admitted to another surgical unit within the same hospital served as the control group (group 1). Perioperative blood samples were taken for haematimetric, iron metabolism and inflammatory parameter determination.

RESULTS

This blood-saving protocol reduced the number of transfused patients (P < 0.001), the number of transfused units (P < 0.0001), increased the reticulocyte count and improved iron metabolism. In addition, the blood-saving protocol also reduced the rate of postoperative infections (P = 0.016), but not the 30-day mortality rate or the mean length of hospital stay.

CONCLUSIONS

The blood-saving protocol implemented seems to reduce ABT requirements in patients with HF, and is associated with a lower postoperative morbidity. The possible mechanisms involved in these effects are discussed.

Activity and resistance of iron-containing amorphous, zeolitic and mesostructured materials for wet peroxide oxidation of phenol

Iron-containing materials have been prepared following several strategies of synthesis and using different silica supports (amorphous, zeolitic and mesostructured materials). Activity and stability of these materials was evaluated on the wet peroxide oxidation of phenol under mild reaction conditions (100 degrees C, air pressure of 1MPa and stoichiometric amount of hydrogen peroxide for the complete mineralisation of phenol). Their catalytic performance was monitored in terms of phenol and total organic carbon (TOC) conversions, by-products distribution (aromatics compounds and carboxylic acids) and degree of metal leached into the aqueous solution. The nature and local environment of iron species is strongly dependent on the synthetic route, which dramatically influences their catalytic performance. Crystalline iron oxide species supported over mesostructured SBA-15 materials have demonstrated to be the most interesting catalysts for phenol degradation according to its high organic mineralisation, low sensitivity to leaching out and good oxidant efficiency.

Iron affects the structure of cell membrane molecular models

The effects of Fe(3+) and Fe(2+) on molecular models of biomembranes were investigated. These consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and of dimyristoylphosphatidylethanolamine (DMPE), classes of phospholipids located in the outer and inner moieties of cell membranes, respectively. X-ray studies showed that very low concentrations of Fe(3+) affected DMPC organization and 10(-3)M induced a total loss of its multilamellar periodic stacking. Experiments carried out with Fe(2+) on DMPC showed weaker effects than those induced by Fe(3+) ions. Similar experiments were performed on DMPE bilayers. Fe(3+) from 10(-7)M up to 10(-4)M had practically no effect on DMPE structure. However, 10(-3)M Fe(3+) induced a deep perturbation of the multilamellar structure of DMPE. However, 10(-3)M Fe(2+) had no effect on DMPE organization practically. Differential scanning calorimetry measurements also revealed different effects of Fe(3+) and Fe(2+) on the phase transition and other thermal properties of the examined lipids. In conclusion, the results obtained indicate that iron ions interact with phospholipid bilayers perturbing their structures. These findings are consistent with the observation that iron ions change cell membrane fluidity and, therefore, affect its functions.

192 PROBLEMS USING JC-1 TO ASSESS MITOCHONDRIAL STATUS IN BROWN BEAR (URSUS ARCTOS) SEMEN

Brown bear is a highly endangered species in Spain and could benefit from biological resource banking. Currently, we are studying several reproductive aspects in order to aquire the knowledge for establishment of a germplasm bank for this species. One of our objectives is to develop adequate protocols for the evaluation of bear sperm before and after cryopreservation. We have used the fluorescent probe JC-1 protocol, which differentially stains mitochondria, according to its activity (Garner DL et al. 1997 Biol. Reprod. 57, 1401–1406). Here we describe one problem that arose using this staining for evaluation of extended bear semen. We electroejaculated 13 adult brown bears (Ursus arctos) (206–311 kg) housed in a half-freedom regime in the Cabarceno Park (Cantabria, Spain). Anesthesia was performed with tiletamine + zolazepan (Zoletil 100®, 7 mg/kg; Virbac, Spain), and ketamine (Imalgene 1000®, 2 mg/kg; Mericl, Sain). We used an electroejaculator (PT Electronics®; Boring, OR, USA) with a 3-electrode transrectal probe (26 mm in diameter, 320 mm long). Ejaculation occurred at 10 V/250 mA. Samples were extended (prepared in our laboratory, Anel L et al. 2003 Theriogenology 60, 1293–1308; M3 modified) and cooled to 5°C for 70 min (pre-freezing protocol). We analyzed individual (MI) and progressive (MP) motility by means of an automated motility analyzer (Hamilton Thorne Biosciences, Inc., Beverly, MA, USA), using a phase contrast microscope (Nikon, ×10). Mitochondrial status was analyzed after diluting the sample 1:100 with buffered medium (20 mM HEPES, 153 mM NaCl, 2.5 mM KOH, 10 mM glucose; Sigma, Madrid, Spain) and adding JC-1 (6.8 μM final; Molecular Probes, The Netherlands). After 30 min at 37°C, 100 cells were counted with an epifluorescence microscope (Nikon, ×400), determining the percentage of sperm with orange-stained (active) mitochondria. We analyzed a total of 55 samples in three different models: fresh, pre-freezing, and thawed. We divided the samples into successful JC-1 staining (valids: V) or failed JC-1 staining (not valid: NV) (depending on the aspect of the stained cells). In not-valid samples we observed a greenish background, with almost no fluorescent spermatozoa. These observations were consistent in a given sample, giving the same V or NV result when we repeated the staining. In fresh and thawed groups there were no NV samples, but in the pre-freezing group there were 40 NV samples (73%). We calculated Pearson correlations (SAS; SAS Institute, Inc., Cary, NC, USA) between percent JC-1 orange population and MI and MP in fresh (r = 0.40 and 0.33; P < 0.001), thawed (r = 0.61 and 0.43; P < 0.001) and pre-freezing samples (r = −0.11 and −0.24; P > 0.05), all respectively. When pre-freezing samples were split between V and NV, the former had good correlations (r = 0.74 and 0.49; P < 0.05), and NV still did not (r = −0.17, −0.27; P > 0.05). We conclude that JC-1 staining is not reliable for the pre-freezing analysis of bear sperm, at least under the conditions described here. This could be due to the interaction of the extender or the refrigeration treatment with the sperm. However, this problem did not occur in the analysis of fresh and thawed samples. Nevertheless, it may be advisable to test other mitochondrial probes for analyzing this kind of samples.

Intronic L1 insertion and F268S, novel mutations in RPS6KA3 (RSK2) causing Coffin-Lowry syndrome

Two novel mutations of the ribosomal S6 kinase 2 gene (also known as RSK2) have been identified in two unrelated patients with Coffin-Lowry syndrome. The first mutation consists of a de novo insertion of a 5'-truncated LINE-1 element at position -8 of intron 3, which leads to a skipping of exon 4, leading to a shift of the reading frame and a premature stop codon. The L1 fragment (2800 bp) showed a rearrangement with a small deletion, a partial inversion of the ORF 2, flanked by short direct repeats which duplicate the acceptor splice site. However, cDNA analysis of the patient shows that both sites are apparently not functional. The second family showed the nucleotide change 803T>C in exon 10, resulting in the F268S mutation. This mutation was detected in two monozygotic twin patients and in their mother, who was mildly affected. The patients fulfill the clinical criteria of the syndrome, and therefore the mutation provides further support for the importance of phenylalanine at position 268, which is highly conserved in the protein kinase domain of many serine-threonine protein kinases.

Budd-Chiari syndrome caused by membranous obstruction of the inferior vena cava associated with coeliac disease

Ten cases of Budd-Chiari syndrome associated with coeliac disease have been reported in the literature, most of them in North African subjects. Supporting this association, we report a new case in a young Spanish Caucasian man in whom the cause of the syndrome was the membranous obstruction of the inferior vena cava, an infrequent cause of Budd-Chiari syndrome in Western countries. A percutaneous balloon angioplasty was performed, with satisfactory outcome.

The Stability of 2-Acetoxy-4-trifluoromethylbenzoic acid (Triflusal) in Micellar Pseudophase

The new platelet antiaggregant Triflusal or 2-acetoxy-4-trifluoromethylbenzoic acid presents a structural analogy to acetylsalicylic acid (ASA). Alkaline hydrolysis of triflusal was studied in the presence and absence of cationic micelles of N-cetyl-N-ethyl-N,N-dimethylammonium bromide (CDEABr) at different KOH concentrations and different temperatures (25, 30, and 37 degrees C) using a spectrophotometric method. The influence of potassium bromide concentration upon alkaline hydrolysis at 25 degrees C is also discussed. At constant [KOH] pseudofirst-rate constant (k(obs)) decreased with increasing [CDEABr] at concentrations greater than the CMC and also decreased with increasing [KBr] at constant [KOH] and [CDEABr]. To explain the effect of cationic micelles of CDEABr upon alkaline hydrolysis, the pseudophase ion exchange model was used. The values of the micellar properties such as the critical micelle concentration, the degree of micellar ionization and the neutralized fraction of the head group obtained by conductivity measurements were determined previously.

[MIBI and parathyroid gland function in secondary hyperparathyroidism]

The role of the double phase parathyroid scintigraphy with MIBI in the primary hyperparathyroidism has been well studied. The present work analyzes the benefit of this image technique in the diagnosis and therapeutic approach to uremia associated hyperparathyroidism. We studied 18 dialysis patients with clinical and analytical data of hyperparathyroidism. All of them were receiving treatment with i.v. vitamin D. We carried out two scintigraphic studies, the first under basal conditions (without changes in treatment) and the second one, a week later after the stimulation of the parathyroid gland through the cessation of the treatment with vitamin D and phosphorus binders, and the use of a low-calcium dialysate. In the basal study, fourteen patients had a positive uptake test in at least one of the four glands. These patients had significantly higher PTHi levels than those with a negative scintigraphic study. After the stimulation test, we found a statistically significative rise in PHTi (644 vs 979 p < 0.001) and phosphorus levels (5.8 vs 7.3; p < 0.01), a slight fall in calcium levels (p = NS) and a statistically significative increment in the score of scintigraphic captation (5.5 +/- 4.5 vs 6.8 +/- 5; p < 0.05). We found a statistically significative correlation between the PTHi level and the score of scintigraphic uptake, in the basal study (r = 0.6, p < 0.01) and after stimulation (r = 0.6, p < 0.01). The only variable associated with the scintigraphic uptake was PTHi, justifying 31.1% of the variance in the first study and 32.7% in the second. In conclusion, the MIBI scintigraphic is a useful exploration in the uremic patient with hyperparathyroidism, as it predicts the functional state of the parathyroid glands according to uptake intensity. The stimulation test could be useful in planning therapy, but some of its characteristics need to be established, such as the precise time to reach the maximum level of parathyroid stimulation.

Variaciones del sector anterior del polígono de Willis. Correlación anatomo-angiográfica y su implicancia en la cirugía de aneurismas intracraneanos (Arterias: ácigos cerebral anterior, mediana del cuerpo calloso y cerebral media accesoria)

It is worlwide accepted that in almost 60% of cases, anatomical variants in the Circle of Willis can be found. Some of them are associated with vascular malformations such as aneurysms. The knowledge of these anatomical variants is of vital importance when facing surgery, being the aims to preserve arteries in unusual localisations, which when injured can determine invalidating sequelae. The authors have reviewed 192 cerebral hemispheres, finding three variants in the anterior Circle of Willis: Azigos anterior cerebral artery; Median artery of the corpus callosum and accessory middle cerebral artery. The authors make an anatomical description of the findings, their angiographical correlation, and describe the influence of these changes during surgery of aneurysms in the involved regions.

Effect of two thermal regimes on the muscle growth dynamics of sea bass larvae, Dicentrarchus labrax L

Muscle growth was studied in larvae of sea bass, Dicentrarchus labrax L., reared at two temperatures: real ambient temperature ( congruent with 15 degrees C during vitelline phase and increased gradually) and 19 degrees C from fertilization until the end of larval development. Muscle cellularity, body length and body weight were measured. Early temperature influenced larval development and so, pre-larval phase finished earlier at 19 degrees C than at ambient temperature (4 and 6 days, respectively). Temperature also affected muscle growth such that at hatching and at mouth opening hypertrophy of muscle fibres was greater at 19 degrees C (P < 0.05), whereas hyperplasia was similar in both groups. After 25 days, the cross-sectional area of the white muscle was greater at 19 degrees C (P < 0.05), which was mainly associated with a higher proliferation of new white muscle fibres. At this stage the body length was also higher at 19 degrees C. Metamorphosis finished earlier in fish reared at 19 degrees C (52 days) than at natural temperature (82 days). At this developmental stage body length and cross-sectional area of the myotome were similar in both groups. However, muscle cellularity differed between groups. Thus, hypertrophy of muscle fibres was higher in fish reared at ambient temperature (P < 0.05), whereas proliferation of new muscle fibres was higher at 19 degrees C (P > 0.05).

X-linked hydrocephalus: another two families with an L1 mutation

X-linked hydrocephalus is a variable condition caused by mutations in the gene encoding for L1CAM. This gene is located at Xq28. Clinically the spectrum ranges from males with lethal congenital hydrocephalus to mild/moderate mental retardation and spastic paraplegia. Few carrier females show minimal signs of the syndrome. Although most cases are familial, de novo situations have been reported. We report two new families with the syndrome and a L1 mutation. Family 1 has two patients and family 2 a single patient. Clinical diagnosis in all three affected boys was beyond doubt. Prenatal testing through chorionic villus biopsy is possible only with a demonstrated L1 mutation. In lethal sporadic cases neuropathology is very important in order to evaluate for features of the syndrome. We stress the importance of further clinical reports including data on neuropathology and DNA analysis in order to further understand the mechanisms involved in this disorder.

Effects on run-off water quantity and quality of urban organic wastes applied in a degraded semi-arid ecosystem

Biosolids and composted municipal solid wastes were surface-applied (0 and 80 Mg ha(-1)) to a degraded soil in a semi-arid environment to determine their effects on the quantity and quality of run-off water. Three and 4 years after application, a simulated rainfall was performed (intensity=942.5 ml min(-1) and kinetic energy=3.92 J m(-2)) on 0.078 m(2) plots using a portable rainfall simulator. The run-off from the different treatment plots was collected and analysed. The type of treatment was highly related to infiltration, run-off and sediment production. The biosolid-treated plots showed the minimum value of total run-off, maximum time to the beginning of run-off and maximum run-off ratio (the relationship between total rainfall and run-off). The MSW-treated plots showed values intermediate between biosolid-treated plots and control plots. Soil losses were also closely related to treatment type. Control plots showed the maximum sediment yield, MSW-treated plots showed intermediate values, and biosolid plots the minimum values for washout. The concentrations of NH(4)-N and PO(4)-P in the run-off water were significantly higher in the treated plots than in control plots. The highest PO(4)-P value, 0.73 mg l(-1), was obtained in the soil treated with biosolids; NO(3)-N concentration also increased significantly with respect to the control and MSW treatments. NH(4)-N concentrations of 15.6 and 15.0 mg l(-1) were recorded in the soils treated with biosolids and MSW, respectively, values approximately five times higher than those obtained in run-off water from untreated soil. However, the concentrations of all these constituents were lower than threshold limits cited in water quality standards for agricultural use. With the exception of Cu, all trace metals analysed in the run-off water were below detection limits.

Biowaste effects on soil and native plants in a semiarid ecosystem

Many soils of the Mediterranean region with a semiarid climate are subjected to progressive degradation as a result of water erosion. Biosolids and municipal solid wastes (MSW) were surface-applied once at three rates (40, 80, and 120 Mg ha(-1)) to different plots in a degraded semiarid ecosystem. The study was conducted to determine the effects of such applications on soil chemical properties and native vegetation over a three-year period. Soil N, P, and K initially increased with increasing biowaste application rates, but then decreased over time. Levels of Zn and Cu were higher in MSW than biosolid-treated plots, and increased in both years after application. Concentrations of soil Cd, Pb, Ni, and Cr did not change as a result of biowaste amendment in the study period. The growth of native plants was enhanced by the addition of biowastes. Total plant canopy and plant biomass increased significantly and remained higher in all treatments than in the control plot over the three-year period. The species richness of native plants decreased with increasing biowaste rates. Differences in the development of native plant communities between treatments were observed, and were more remarkable three years after biowaste application. Tissue N, P, K, Zn, and Cu levels increased with the biowaste application rate, but concentrations of tissue Pb, Cd, Ni, and Cr did not increase significantly. Biowastes applied at the rate of 80 Mg ha(-1) gave rise to the most favorable soil and native vegetation results while avoiding environmental risks.

Minimal Residual Disease in Neuroblastoma: To GAGE or not to GAGE

We assessed the utility of GAGE gene expression as a marker of minimal residual disease (MRD) in neuroblastoma. The GAGE gene family shows a high degree of homology (>90%), clustering into two subgroups. GAGE-1, -2, and -8 form one subset, almost identical among themselves, while GAGE-3 to -7 constitute the other subset. The entire GAGE family (GAGE-1-8) was studied by RT-PCR followed by Southern blotting to increase both the sensitivity and specificity of the technique. Surprisingly, expression of GAGE was detected in 59% of peripheral blood samples from normal controls (20/35) as well as in a similar proportion from neuroblastoma patients with localized disease (stages 1 and 2). The study of GAGE-1, -2, and -8 with specific primers lowered this percentage to 28% (10/35), of which only two (6%) showed a high level of expression (directly visualized after RT-PCR). We conclude that GAGE genes can show a variable, usually low level of illegitimate expression in normal blood cells, and therefore their use as MRD markers should be taken with caution.