The rye transcription factor ScSTOP1 regulates the tolerance to aluminum by activating the ALMT1 transporter

Plants have evolved different mechanisms to increase their tolerance to aluminum (Al) toxicity and low pH in the soil. The Zn finger transcription factor SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1) plays an essential role in the adaptation of plants to Al and low pH stresses. In this work, we isolated the ScSTOP1 gene from rye (Secale cereale L.), which is located on chromosome 3RS. The ectopic expression of ScSTOP1 complements the Arabidopsis stop1 mutation in terms of root growth inhibition due to Al and pH stress, as well as phosphate starvation tolerance, suggesting that rye ScSTOP1 is a functional ortholog of AtSTOP1. A putative STOP1 binding motif was identified in the promoter of a well-known STOP1 target from rye and Arabidopsis and was later corroborated by genomic DAP-seq analyses. Coexpression analyses verified that ScSTOP1 activated the promoter of ScALMT1. We have also identified a putative phosphorylatable serine in STOP1 that is phylogenetically conserved and critical for such activation. Our data indicated that ScSTOP1 also regulated Al and pH tolerance in rye.

Isolation and characterization of a new MATE gene located in the same chromosome arm of the aluminium tolerance (Alt1) rye locus

Aluminium (Al) toxicity is the major constraint for crop productivity in acid soils. Wild rye species (Secale spp.) exhibit high Al tolerance, being a good source of genes related to this trait. The Alt1 locus located on the 6RS chromosome arm is one of the four main loci controlling Al tolerance in rye and is known to harbour major genes but, so far, none have been found. Through synteny among the short arm of the rye chromosome 6R and the main grass species, we found a candidate MATE gene for the Atl1 locus, later named ScMATE3, which was isolated and characterized in different Secale species. The sequence comparisons revealed both intraspecific and interspecific variability, with high sequence conservation in the Secale genus. SNP with replacement substitution that changed the structure of the protein and can be involved in the Al tolerance trait were found in ScMATE3 gene. The predicted subcellular localization of ScMATE3 is the vacuolar membrane which, together with the phylogenetic relationships performed with other MATE genes of the Poaceae related to Al detoxification, suggest involvement of ScMATE3 in an internal tolerance mechanism. Moreover, expression studies of this gene in rye corroborate its contribution in some Al resistance mechanisms. The ScMATE3 gene is located on the 6RS chromosome arm between the same markers in which the Alt1 locus is involved in Al resistance mechanisms in rye, thus being a good candidate gene for this function.

Dorsolateral prefrontal N-acetyl-aspartate concentration in male patients with chronic schizophrenia and with chronic bipolar disorder

Objectives

A study of N-acetyl-aspartate (NAA) can provide data of interest about cortical alterations in psychotic illnesses. Although a decreased NAA level in the cerebral cortex is a replicated finding in chronic schizophrenia, the data are less consistent for bipolar disease. On the other hand, it is likely that NAA values in schizophrenia may differ in men and women.

Methods

We used proton magnetic resonance spectroscopy (1H MRS) to examine NAA levels in the prefrontal cortex in two groups of male patients, one with schizophrenia (n = 11) and the other with bipolar disorder (n = 13) of similar duration, and compared them to a sample of healthy control males (n = 10). Additionally, we compared the degree of structural deviations from normal volumes of gray matter (GM) and cerebrospinal fluid (CSF) in the dorsolateral prefrontal cortex.

Results

Compared to controls, schizophrenia and bipolar patients presented decreased NAA to creatine ratios, while only the schizophrenia group showed an increase in CSF in the dorsolateral prefrontal region. There were no differences in choline to creatine ratios among the groups.

Conclusions

These data suggest that the decrease in NAA in the prefrontal region may be similar in schizophrenia and bipolar disorder, at least in the chronic state. However, cortical CSF may be markedly increased in schizophrenia patients.

Effectiveness of commercial face masks to reduce personal PM exposure

Cycling and walking are promoted as means of transportation which can contribute to the reduction of traffic pollution in urban areas. However, cyclists and pedestrians may be exposed to high concentrations of air pollutants due to their proximity to vehicle emissions. Commercial face mask respirators are widely used, in both developing and developed countries, as an individual protective measure against particle pollution. However scientific data on the efficacy of face mask respirators in reducing airborne particle exposure is limited. In this study, a custom experimental set-up was developed in order to measure the effectiveness of nine different respirators under real environmental conditions in terms of particle mass concentration below 2.5 μm (PM_2.5), particle number concentration (PNC), Lung Deposited Surface Area (LDSA) and Black Carbon concentration (BC). Face mask performances were assessed in a typical traffic affected urban background environment in the city of Barcelona under three different simulated breathing rates to investigate the influence of flow rate. Results showed a median face mask effectiveness for PM_2.5 equal to 48% in a range of 14-96%, 19% in a range of 6%-61% for BC concentration, 19% in a range of 4%-63% for PNC and 22% in a range of 5%-65% for LDSA. For each pollutant under investigation, the best performance was found always with the same mask (N7) although it is not the most expensive (in a range of price of 1 to 44, its cost was 20 euros), which has a filter on the entire surface except for the 2 exhalation valves where air cannot enter but just exit and shows a good fit on the dummy head.

Molecular cloning of TaMATE2 homoeologues potentially related to aluminium tolerance in bread wheat (Triticum aestivum L.)

Recently, members of the MATE family have been implicated in aluminium (Al) tolerance by facilitating citrate efflux in plants. The aim of the present work was to perform a molecular characterisation of the MATE2 gene in bread wheat. Here, we cloned a member of the MATE gene family in bread wheat and named it TaMATE2, which showed the typical secondary structure of MATE-type transporters maintaining all the 12 transmembrane domains. Amplification in Chinese Spring nulli-tetrasomic and ditelosomic lines revealed that TaMATE2 is located on the long arm of homoeologous group 1 chromosomes. The transcript expression of TaMATE2 homoeologues in two diverse bread wheat genotypes, Barbela 7/72/92 (Al-tolerant) and Anahuac (Al-sensitive), suggested that TaMATE2 is expressed in both root and shoot tissues of bread wheat, but mainly confined to root rather than shoot tissues. A time-course analysis of TaMATE2 homoeologue transcript expression revealed the Al responsive expression of TaMATE2 in root apices of the Al-tolerant genotype, Barbela 7/72/92. Considering the high similarity of TaMATE2 together with similar Al responsive expression pattern as of ScFRDL2 from rye and OsFRDL2 from rice, it is likely that TaMATE2 also encodes a citrate transporter. Furthermore, the TaMATE2-D homoeologue appears to be near the previously reported locus (wPt0077) on chromosome 1D for Al tolerance. In conclusion, molecular cloning of TaMATE2 homoeologues, particularly TaMATE2-D, provides a plausible candidate for Al tolerance in bread wheat that can be used for the development of more Al-tolerant cultivars in this staple crop.

The role of two superoxide dismutase mRNAs in rye aluminium tolerance

Aluminium (Al) is the main factor that limits crop production in acidic soils. There is evidence that antioxidant enzymes such as superoxide dismutase (SOD) play a key role against Al-induced oxidative stress in several plant species. Rye is one of the most Al-tolerant cereals and exudes both citrate and malate from the roots in response to Al. The role of SOD against Al-induced oxidative stress has not been studied in rye. Al accumulation, lipid peroxidation, H₂O₂ production and cell death were significantly higher in sensitive than in tolerant rye cultivars. Also, we characterised two genes for rye SOD: ScCu/ZnSOD and ScMnSOD. These genes were located on the chromosome arms of 2RS and 3RL, respectively, and their corresponding hypothetical proteins were putatively classified as cytosolic and mitochondrial, respectively. The phylogenetic relationships indicate that the two rye genes are orthologous to the corresponding genes of other Poaceae species. In addition, we studied Al-induced changes in the expression profiles of mRNAs from ScCu/ZnSOD and ScMnSOD in the roots and leaves of tolerant Petkus and sensitive Riodeva rye. These genes are mainly expressed in roots in both ryes, their repression being induced by Al. The tolerant cultivar has more of both mRNAs than the sensitive line, indicating that they are probably involved in Al tolerance.

On the consequences of aluminium stress in rye: repression of two mitochondrial malate dehydrogenase mRNAs

Plants have developed several external and internal aluminium (Al) tolerance mechanisms. The external mechanism best characterised is the exudation of organic acids induced by Al. Rye (Secale cereale L.), one of the most Al-tolerant cereal crops, secretes both citrate and malate from its roots in response to Al. However, the role of malate dehydrogenase (MDH) genes in Al-induced stress has not been studied in rye. We have isolated the ScMDH1 and ScMDH2 genes, encoding two different mitochondrial MDH isozymes, in three Al-tolerant rye cultivars (Ailés, Imperial and Petkus) and one sensitive inbred rye line (Riodeva). These genes, which have seven exons and six introns, were located on the 1R (ScMDH1) and 3RL (ScMDH2) chromosomes. Exon 1 of ScMDH1 and exon 7 of ScMDH2 were the most variable among the different ryes. The hypothetical proteins encoded by these genes were classified as putative mitochondrial MDH isoforms. The phylogenetic relationships obtained using both cDNA and protein sequences indicated that the ScMDH1 and ScMDH2 proteins are orthologous to mitochondrial MDH1 and MDH2 proteins of different Poaceae species. The expression studies of the ScMDH1 and ScMDH2 genes indicate that it is more intense in roots than in leaves. Moreover, the amount of their corresponding mRNAs in roots from plants treated and not treated with Al was higher in the tolerant cultivar Petkus than in the sensitive inbred line Riodeva. In addition, ScMDH1 and ScMDH2 mRNA levels decreased in response to Al stress (repressive behaviour) in the roots of both the tolerant Petkus and the sensitive line Riodeva.

Correction of distal limb prolapse of a diverting colostomy by stapling under sedation

AIM

To describe a surgical technique to treat colostomy prolapse as a day case procedure with the patient under sedation and analgesia.

METHOD

A 60-mm GIA Universal Stapler is inserted into the lumen of the prolapsed colon at right angles to the contour of the abdominal wall. Several firings are then made to completely divide the prolapsed colon. The instrument is then placed parallel to the skin to remove the prolapsed portion leaving 1-2 cm of bowel above the level of the skin.

RESULTS

Two patients underwent the procedure. The operation times were 30 and 13 min. Both took oral liquids 2 h after surgery and solids 2 h later. They were discharged at 24 and 4 h after surgery, respectively. No postoperative pain was reported in either case. At 14 and 6 months of follow-up there has been no recurrence.

CONCLUSION

Stapling treatment of prolapsed colostomies has the advantage of being an extra-abdominal procedure. It is performed under sedation and analgesia, the operation time is very short, recovery to normal life is rapid and there is less likelihood of complications by avoiding a laparotomy.

Optimization by experimental design of polyacrylamide gel composition as support for enzyme immobilization by entrapment

We have developed a methodology based on experimental design, to optimize a polyacrylamide gel as the support for enzyme immobilization, taking advantage of all the properties which this type of gel has. Monomer and crosslinking agent proportions are responsible for both the porous structure and pore size of the gel. A correct selection of those variables and suitable synthesis conditions leads to an increase in the activity retained by the gel. The path of steepest ascent method was used to obtain the relative maximum activity. The maximum retained activity was chosen with a central composite design in terms of the gel composition. The retained activity in the network, loss activity in the wash water, and loss activity due to steric impediment or blockage was modeled in terms of the variables responsible for the gel structure. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 53: 497-506, 1997.

[Combined regional-general anesthesia with use of the Proseal laryngeal mask during prolonged peripheral plastic surgery]

The ProSeal laryngeal mask offers a better interface for controlled ventilation than does a traditional mask because of the ProSeal's improved airway seal and the possibility of draining the digestive tract. Limb reconstructive surgery is normally a long procedure involving the use of grafts or flaps located at a distance from the lesion. Regional anesthesia is therefore of limited use. We report a series of 24 adult patients who underwent peripheral plastic surgery under combined regional and general intravenous anesthesia and in whom the ProSeal mask was used. Data recorded included assessment of the airway and intubation difficulty, disease and duration of the procedure, type of regional anesthesia, respiratory and hemodynamic variables, patient satisfaction, laryngeal complications, and postoperative analgesia. All patients were adequately ventilated. One episode of bradycardia was controlled with atropine. In the immediate postoperative period, no patient presented laryngeal complications and only 1 patient reported significant pain (8 on a visual analog scale). The ProSeal mask was a good choice for use with combined regional-general anesthesia, ensuring control of the airway without causing complications. Analgesia was adequate in most cases.

Differential clinical, structural and P300 parameters in schizophrenia patients resistant to conventional neuroleptics

Schizophrenia is a heterogeneous clinical condition that may reflect a variety of biological processes. In particular, treatment-resistant (TR) schizophrenia may have a distinct neurobiological substrate. Within the context of clinical data, a simultaneous study with different imaging techniques could help to elucidate differences in cerebral substrates among schizophrenia patients with different responses to treatment. In the present work we used a set of biological data (basal and longitudinal volumetry, and P300 event-related potential measurements) to compare TR and treatment-responsive chronic schizophrenia patients with healthy controls. The TR patients showed higher baseline clinical scores, a more severe basal profile of brain alterations, as well as a different outcome as regards to volume deficits. These data support the notion that biological substrates vary among groups of different psychotic patients, even when they have the same diagnosis, and that those substrates may be related to the response to treatment.

Glial expression of cannabinoid CB(2) receptors and fatty acid amide hydrolase are beta amyloid-linked events in Down's syndrome

Recent data suggest that the endocannabinoid system (ECS) may be involved in the glial response in different types of brain injury. Both acute and chronic insults seem to trigger a shift in the pattern of expression of some elements of this system from neuronal to glial. Specifically, data obtained in human brain tissue sections from Alzheimer's disease patients showed that the expression of cannabinoid receptors of the CB(2) type is induced in activated microglial cells while fatty acid amide hydrolase (FAAH) expression is increased in reactive astrocytes. The present study was designed to determine the time-course of the shift from neuronal to glial induction in the expression of these proteins in Down's syndrome, sometimes referred to as a human model of Alzheimer-like beta-amyloid (Abeta) deposition. Here we present immunohistochemical evidence that both CB(2) receptors and FAAH enzyme are induced in Abeta plaque-associated microglia and astroglia, respectively, in Down's syndrome. These results suggest that the induction of these elements of the ECS contributes to, or is a result of, amyloid deposition and subsequent plaque formation. In addition, they confirm a striking differential pattern of distribution of FAAH and CB(2) receptors.

Changes in Cortical Volume with Olanzapine in Chronic Schizophrenia

INTRODUCTION

Atypical antipsychotics can affect cortical volume differently from traditional drugs. The study of the outcome of grey matter deficits in schizophrenia with olanzapine may be of particular interest in this context.

METHODS

In this study, we evaluated the changes in the volume of gray matter in the cortex of 11 schizophrenic patients treated with olanzapine and in 11 healthy controls after three years of follow-up. After MR imaging, acquisition data were processed with a volumetric quantification method based on the Talairach atlas. The longitudinal change of volumetric data was corrected for differences in overall brain size.

RESULTS

Patients showed greater reduction than controls in cortical volume in the frontal and parietal regions during follow-up. No relationship was observed between clinical and volumetric changes.

CONCLUSION

Our data suggest that the profile of action of olanzapine on the cortical volume of chronically ill patients may be similar to that of typical antipsychotics. Other explanations, however, cannot be completely discarded for that outcome with our data.

Candidate gene identification of an aluminum-activated organic acid transporter gene at the Alt4 locus for aluminum tolerance in rye (Secale cereale L.)

Among cereal crops, rye is one of the most tolerant species to aluminum. A candidate gene approach was used to determine the likely molecular identity of an Al tolerance locus (Alt4). Using PCR primers designed from a wheat aluminum tolerance gene encoding an aluminum-activated malate transporter (TaALMT1), a rye gene (ScALMT1) was amplified, cloned and sequenced. Subsequently, the ScALMT1 gene of rye was found to be located on 7RS by PCR amplification using the wheat-rye addition lines. SNP polymorphisms for this gene were detected among the parents of three F(2) populations that segregate for the Alt4 locus. A map of the rye chromosome 7R, including the Alt4 locus ScALMT1 and several molecular markers, was constructed showing a complete co-segregation between Alt4 and ScALMT1. Furthermore, expression experiments were carried out to clarify the function of this candidate gene. Briefly, the ScALMT1 gene was found to be primarily expressed in the root apex and upregulated when aluminum was present in the medium. Five-fold differences in the expression were found between the Al tolerant and the Al non-tolerant genotypes. Additionally, much higher expression was detected in the rye genotypes than the moderately tolerant "Chinese Spring" wheat cultivar. These results suggest that the Alt4 locus encodes an aluminum-activated organic acid transporter gene that could be utilized to increase Al tolerance in Al sensitive plant species. Finally, TaALMT1 homologous sequences were identified in different grasses and in the dicotyledonous plant Phaseolus vulgaris. Our data support the hypothesis of the existence of a common mechanism of Al tolerance encoded by a gene located in the homoeologous group four of cereals.

Liver Transplantation: Experience With Our First 100 Cases

OBJECTIVES

Our goal was to evaluate the results of the first 100 liver transplants performed in our institution.

METHODS

We retrospectively analyzed the first 100 liver transplants undertaken in adults from November 2001 to August 2005.

RESULTS

The mean age of the recipients was 50 years (20 to 69) and 73% were men. The mean waiting time was 35 days. The mean age of the donors was 60 years (15 to 87), and 60% were men. One-year patient and graft survival rates were 93% and 90%, respectively. Three-year patient and graft survival rates were 85% and 82%, respectively. The need for retransplantation was 3%. Surgical complications included hepatic artery stenoses, 2%; hepatic artery thromboses, 2%; biliary leaks, 6%; and biliary stenoses, 14%.

CONCLUSIONS

These results are no different from the overall results for liver transplantation in Spain during the same period.

Molecular characterization of Trichinella genotypes by inter-simple sequence repeat polymerase chain reaction (ISSR-PCR)

A bulk analysis of inter-simple sequence repeat-polymerase chain reaction (ISSR-PCR) provides a quick, reliable, and highly informative system for DNA banding patterns that permit species identification. The present study evaluates the applicability of this system to Trichinella species identification. After a single amplification carried out on a single larva with the primer 816([CA]nRY) under high stringency conditions, which provide high reproducibility, we were able to identify by consistent banding patterns 5 sibling species: Trichinella spiralis (ISS48), 2 Trichinella britovi isolates (ISS11 and ISS86), Trichinella murrelli (ISS35), Trichinella nativa (ISS71), Trichinella nelsoni (ISS29); 3 additional Trichinella genotypes: T8 (ISS149), T9 (ISS408 and ISS409), and T6 (ISS34); and the nonencapsulated species Trichinella pseudospiralis (ISS13). Moreover, 33 new Trichinella isolates from 2 zoogeographical regions were unequivocally identified. All Trichinella isolates have shown an identical pattern with those produced by the reference strain. According to these data, we have demonstrated that ISSR-PCR is a robust technique that emerges as a useful new application for the molecular identification of Trichinella isolates in epidemiological studies.

Leishmaniasis as an opportunistic infection in HIV-infected patients: determinants of relapse and mortality in a collaborative study of 228 episodes in a Mediterreanean region

The clinical presentation of visceral leishmaniasis shares similarities with other geographically specific infectious diseases associated with AIDS in terms of relapsing course and atypical presentation. However, visceral leishmaniasis has not, until now, been included in the AIDS case definition. The aim of this study was to describe the clinical features and determinants for relapse and case-fatality of visceral leishmaniasis in HIV-infected patients from a Spanish Mediterranean area. A chart review was conducted in 16 hospitals in the autonomous communities of Valencia and Murcia (Spain). From 1988 to 2001, a total of 228 episodes of visceral leishmaniasis were diagnosed in 155 HIV-infected patients by the detection of amastigotes in bone marrow aspirates or in other tissue samples. Most patients had advanced HIV disease, with a median CD4(+) lymphocyte cell count of 55 cells x 10(9) l, and 56% of them had a previous AIDS-indicator disease. The median duration of follow-up was 8.4 months. HIV-infected patients with visceral leishmaniasis presented with fever (76%), hepatomegaly (77%), splenomegaly (78%), and varying degrees of cytopenias. Leishmania was detected in atypical sites in 22 (14%) patients. A total of 37 (24%) patients had a relapse of visceral leishmaniasis. Female gender was a risk factor for relapse, whereas administration of secondary prophylaxis for visceral leishmaniasis and a completed therapy for visceral leishmaniasis were protective factors against relapse. A total of 86 (54%) patients died. Independent determinants for survival were CD4(+) lymphocyte cell count, completed therapy for leishmania, and secondary prophylaxis for visceral leishmaniasis. The findings show that, in HIV-infected patients, visceral leishmaniasis occurs in late stages of HIV disease and often has a relapsing course. Secondary prophylaxis reduces the risk of relapse. Visceral leishmaniasis in the HIV-infected population should be included in the CDC clinical category C for the definition of AIDS in the same way that other geographically specific opportunistic infections are included.

Secale cereale inter-microsatellites (SCIMs): chromosomal location and genetic inheritance

The polymerase chain reaction (PCR) was used to locate Sectale cereale (inter-simple sequence repeat ISSR) or Secale cereale inter-microsatellite (SCIM) markers using wheat-rye addition lines in order to develop a set of molecular markers distributed on the seven rye chromosomes. The number of SCIM markers located on 1R, 2R, 3R, 4R, 5R, 6R and 7R chromosomes were 4, 3, 12, 3, 2, 9 and 8, respectively. Therefore, a total of 41 new SCIMs were located on the seven rye chromosomes. The segregation of the 63 different SCIM markers in three different F2 was studied. The observed ISSR segregations were the 3:1 (50.7%), the 15:1 (12.7%) and the 1:1 (14.2%). The linkage analysis carried out indicated that seven of the segregating SCIMs were linked to chromosome 7R and two were linked to chromosome 4R. The use of the SCIM markers as a source of molecular markers that could be linked to interesting genes or other important agronomic traits is discussed.

A new aluminum tolerance gene located on rye chromosome arm 7RS

Rye has one of the most efficient groups of genes for aluminum tolerance (Alt) among cultivated species of Triticeae. This tolerance is controlled by, at least, three independent and dominant loci (Alt1, Alt2, and Alt3) located on chromosome arms 6RS, 3RS, and 4RL, respectively. The segregation of Alt genes and several random amplified polymorphic DNA (RAPD), Secale cereale inter-microsatellite (SCIM), and Secale cereale microsatellite (SCM) markers in three F(2) between a tolerant cultivar (Ailés) and a non-tolerant inbred line (Riodeva) were studied. The segregation ratio obtained for aluminum tolerance in the three F(2) populations analyzed was 3:1 (tolerant:non-tolerant), indicating that tolerance is controlled by one dominant locus. SCIM811(1376) was linked to an Alt gene in the three F(2) populations studied, and three different SCIMs and one RAPD (SCIM811(1376), SCIM812(626), SCIM812(1138), and OPQ4(725)) were linked to the Alt gene in two F(2) populations. This result indicated that the same Alt gene was segregating in the three crosses. SCIM819(1434) and OPQ4(578) linked to the tolerance gene in one F(2) population were located using wheat-rye ditelosomic addition lines on the 7RS chromosome arm. The Alt locus is mapped between SCIM819(1434) and the OPQ4(578) markers. Two microsatellite loci (SCM-40 and SCM-86), previously located on chromosome 7R, were also linked to the Alt gene. Therefore, the Alt gene segregating in these F(2) populations is new and probably could be orthologous to the Alt genes located on wheat chromosome arm 4DL, on barley chromosome arm 4HL, on rye chromosome arm 4RL, and rice chromosome 3. This new Alt gene located on rye chromosome arm 7RS was named Alt4. A map of rye chromosome 7R with the Alt4 gene, 16 SCIM and RAPD, markers and two SCM markers was obtained.

Hypofrontality in men with first-episode psychosis

BACKGROUND

Decreased metabolic activity in the prefrontal cortex during cognitive activation is a recurrent finding and a likely functional marker of schizophrenia.

AIMS

To investigate the occurrence of hypofrontality in patients with first-episode psychosis, with or without evolution to schizophrenia.

METHOD

We used fluorodeoxyglucose positron emission tomography during the performance of an attention task and magnetic resonance imaging to study the dorsolateral prefrontal region in 13 men with a first episode of psychosis. Data from patients who progressed to schizophrenia were compared with those of patients who did not meet criteria for this diagnosis after 2 years.

RESULTS

Patients who developed schizophrenia demonstrated a significant hypofrontality in the dorsolateral prefrontal cortex in comparison with the non-schizophrenia and control groups.

CONCLUSIONS

Our results suggest that hypofrontality could be a marker of schizophrenia at the time of the first psychotic episode, in agreement with neurodevelopmental theories of schizophrenia.

Role of the endocannabinoid system in Alzheimer's disease: New perspectives

The role of the endocannabinoid system in several diseases is currently under intense study. Among these, Alzheimer's disease may be a new promising area of research. We have recently reported the existence of profound changes in the location and density of several elements of this system in Alzheimer's disease tissue samples, indicating that a non-neuronal endocannabinoid system is up-regulated in activated glia. Additional data from other groups suggest that glial cells may be important elements in the regulation of endocannabinoid system activity, both in health as in disease. Some of these aspects are briefly discussed in the present review.

Phylogenetic relationships among Portuguese rye based on isozyme, RAPD and ISSR markers

The phylogenetic relationships of 10 rye landraces and cultivars from the north of Portugal and from Brazil were analysed using 20 isozyme loci, and a total of 511 PCR markers (342 ISSRs and 169 RAPDs). The isozymes were analysed in at least 100 plants of each population/cultivar and, therefore, we have data about intra and inter population/cultivar genetic variability. However, the analyses with ISSRs and RAPDs were obtained using a mix of 25 plants of each population. Therefore, each population/cultivar was reduced to one tube and we have no data about intra genetic variability. As expected in a cross pollinated crop we found genetic diversity and a larger variation within than among the populations using isozymes. Somewhat unexpectedly, however, we found that the breeding cultivars have the same level of heterozygosity as the landraces. The phylogenetic relationships obtained using isozymes among the landraces, synthetic cultivar and the cultivars from breeding programs do not reflect their origin. Moreover, the cultivar from Brazil is not separated from the remaining populations/cultivars studied. However, the data observed using RAPDs and ISSRs are in agreement with their known origin. The populations maintained by the farmers in the north of Portugal are grouped in a cluster in the phenogram and the C902591 (from Brazil), the Alvão (synthetic variety) and Larouco (a hybrid between Montalegre and Brazil) are in a different cluster. The ISSRs and RAPDs provide a rapid method for the production of polymorphic markers, which appear to correspond to known pedigree information.

The use of ISSR and RAPD markers for detecting DNA polymorphism, genotype identification and genetic diversity among barley cultivars with known origin

The potential of bulk analyses of RAPD and ISSR-PCR markers for fingerprinting purposes was evaluated using ten RAPD and ten ISSR primers. The phylogenetic relationships of 16 barley cultivars from different countries, and all having a known pedigree, were analysed using 353 PCR markers (125 RAPDs and 228 ISSRs). The band profiles generated were reproducible in spite of the different DNA extractions, PCR techniques, electrophoretic methods and gel scorings used. The RAPD primer S10 and four ISSR primers (811, 820, 835 and 881) were both able to distinguish all cultivars. A strong and quite linear relationship was observed between Resolving Power (Rp) of a primer and its ability to distinguish genotypes. The dendrograms obtained using these two molecular markers are in agreement with their known origin, showing clusters that separate very well the spring/winter and six-rows/two-rows cultivars. Thus, bulk analyses of RAPD and ISSR PCR markers provides a quick, reliable and highly informative system for DNA fingerprinting and also permit to establish genetic relationships which agree with, by other means, known origin of the cultivars.

Is the Mnr locus of Triticeae species the same as the Ndh and Dia loci?

The menadione reductase (MNR), the nicotinamide adenine dinucleotide dehydrogenase (NDH) and diaphorase (DIA) isozymes were studied in the allohexaploid Triticum aestivum cv "Chinese Spring" and in five diploid Triticeae species. The Mnr1, Ndh3and Dia1 loci were located on the chromosome arms 3AL, 3BL and 3DL of T. aestivum, respectively. These loci were also located on the 3H chromosome of Hordeum vulgare cv "Betzes", the 3L chromosome of Aegilops longissima and the 6RL chromosome arm of Secale cereale cv "Imperial". The chromosomal location results together with the segregation studies support a tetrameric behaviour of the MNR1, NDH3 and DIA1 isozymes. The Ndh1 and Dia3 loci were located on homoeologous group 4 showing a monomeric behaviour. The chromosomal locations and linkage data of the Mnr, Ndh and Dia loci suggest that Mnr1=Ndh3=Dia1; Ndh1=Dia3 and Ndh2=Dia2.

Mutations in the factor V, prothrombin and MTHFR genes are not risk factors for recurrent fetal loss

OBJECTIVE

Recurrent fetal loss, defined as the occurrence of three or more consecutive spontaneous abortions regardless of previous live birth, is a condition that affects about 2% of all reproductive-aged women. The role of gene mutations in recurrent pregnancy loss is not fully understood. The present research examined the relationship between factor V Leiden, factor V HR2, prothrombin G20210A and MTHFR and recurrent fetal loss in a case-control study.

METHODS

Women aged 22-45 with a history of three or more fetal losses, being seen at a perinatal medicine clinic in New Jersey or Georgia, were eligible as cases. Overall, the study consisted of 60 women with three or more fetal losses and 92 women with at least one successful pregnancy.

RESULTS

Factor V HR2 and MTHFR were not related to recurrent fetal loss. The prothrombin G20210A mutation appeared to confer an elevation in risk but the association was based upon small numbers and was not statistically significant (OR 4.8, 95% CI 0.50-47.2). Cases were 90% less likely to have the factor V Leiden mutation than controls (OR 0.10, 95% CI 0.01-0.81).

CONCLUSIONS

Our study did not demonstrate that women who are carriers of the factor V, prothrombin, or MTHFR mutations are at higher risk of recurrent fetal loss than women without these mutations. In regards to factor V Leiden, the prevalence in our cases (1.7%) was not statistically different from the known population prevalence of 5%. However, the high prevalence in our controls (14%) was unusual. Factor V Leiden may protect against bleeding in early pregnancy.

P300 amplitude as a possible correlate of frontal degeneration in schizophrenia

The existence of neurodegeneration is a debated issue in schizophrenia research. The P300 component of event-related electrical potentials (ERP) has been related to the different degree of damage to gray and white matter. This study explores the possible relationship between P300 amplitude and/or latency and the existence of degenerative processes in schizophrenia, by assessing its correlation with volume of sulcal CSF and duration of illness, as transversal indicators of neurodegeneration. Nineteen patients (14 males, 5 females) and 13 controls (6 males, 7 females) were studied with MRI and electrophysiological records (P300). The possible influence of sex and age at the time of the exploration was statistically controlled in both groups. The results show a significant negative correlation between P300 amplitude and prefrontal CSF volume in the patient group. A lower though still significant correlation was also found between P300 amplitude and duration of illness, whereas no correlation was found in the control group. These results support the hypothesis that P300 amplitude may be interpreted as a marker of neurodegeneration in schizophrenia.

Achieving plasma HIV RNA below the level of detection in clinical practice

Clinical trials have shown that highly active antiretroviral therapy (HAART) reduces plasma HIV RNA below the detection level in up to 90 per cent of patients. To assess the independent predictors that are associated with achieving undetectable plasma HIV RNA in the daily clinical practice, we carried out a retrospective study. Among 106 HIV-infected patients treated with HAART, 63 (59 per cent) achieved undetectable plasma HIV RNA (less than 400 copies/ml) at their last visit. Adherence with HAART (greater than 80 per cent of prescribed dose) was self-reported by 81 patients (76 per cent). Independent predictors of achieving undetectable plasma HIV RNA were: self-reported adherence to therapy (Odds ratio [OR] 11.79, 95 per cent Confidence intervals [CI]: 3.55-33.17, p = 0.0001) and lack of previous antiretroviral therapy (OR: 3.12, 95 per cent CI: 1.09-8.96, p = 0.03). The efficacy of antiretroviral therapy observed in the daily clinical practice was noticeably lower than that reported in clinical trials. Patient adherence with prescribed HAART and lack of previous antiretroviral therapy are important factors related to successful therapy in the real world.

[Risk factors related to infections during the first year of highly active antiretroviral therapy]

BACKGROUND

To evaluate the immunological, virological and clinical response of HIV-infected patients who start combined therapy with protease inhibitors (PI) in a community hospital. To identify risk factors related with infections.

PATIENTS AND METHOD

Clinical review of patients with combined therapy, assessing CD4+ cell counts, viral load (Amplicor) and development of infections during the first year on PI (group A) and comparative study with the same patients during the previous year with PI (group B).

RESULTS

134 patients were included in group A and 84 in Group B. Nadir of CD4+ was 169 X 10(6)/l. After 6 months of PI therapy, the mean CD4 increased from 217 to 355 X 10(6)/l and the median viral load decreased from 88,000 copies/ml (14,000-485,000) to less than 400 copies /ml (< 400-9,000), 60% of patients had less than 400 copies/ml. The incidence of non-opportunistic infections was similar in both groups (36 vs 43%; p = NS). However, the rate of opportunistic infections decreased from 30 to 15% (RR: 0.41 [CI 0.21-0.81]; p = 0.007) in the group with PI, particularly Pneumocystis carinii pneumonia and toxoplasmosis. Multivariated analysis including CD4+ cell count, nadir of CD4+, viral load and risk behavior only nadir of CD4 < 100 X 10(6)/l was associated with a lower risk of developing opportunistic infections (RR: 0.2 [CI: 0.1-0.7]; p = 0.001).

CONCLUSIONS

Combined therapy with PI improved immunological and virological markers and decreased the rate of opportunistic infections. A CD4+ cell count nadir higher than 100 X 10(6)/l was a marker of good prognosis during the first year with PI irrespective of response to therapy.

D-mannoheptulose uptake and its metabolic and secretory effects in human pancreatic islets

D-mannoheptulose was recently proposed to be transported into cells at the intervention of GLUT2. Since GLUT1, rather than GLUT2, represents the major carrier system for the transport of monosaccharides across the islet B-cell plasma membrane in human subjects, the uptake of D-mannoheptulose and its metabolic and secretory effects were investigated in human islets. The uptake of D-glucose reached much more rapidly a close-to-equilibrium value in isolated islets than in pieces of pancreas obtained from the same donor. The distribution space of D-[3H]mannoheptulose in the human islets largely exceeded that of [U-14C]sucrose, considered as an extracellular marker, and did not differ significantly from that of 3HOH. In the human islets, the heptose (10.0 mM) inhibited both D-[5-3H]glucose utilization and D-[U-14C] glucose oxidation, and decreased glucose-stimulated insulin release to the same extent as D-mannoheptulose hexaacetate. These findings indicate that a suitable radioactive analog of D-mannoheptulose could be used, in human like in rat islets, for preferential labelling of the endocrine moiety of the pancreatic gland.

Safety and efficacy of Omniscan (gadodiamide injection) at 0.1 mmol/kg for MRI in infants younger than 6 months of age: phase III open multicenter study

RATIONALE AND OBJECTIVES

To demonstrate that gadodiamide injection is a safe and efficient contrast agent for MRI in infants younger than 6 months of age.

METHODS

The authors designed a phase III multicenter nonrandomized study using a control group. Gadodiamide injection at a dosage of 0.1 mmol/kg body weight was administered to 39 children; 20 received no contrast. The mean age was 10.6 weeks in the contrast group and 9.3 weeks in the control group. MR examinations, blood (serum creatinine, S-ASAT, S-ALAT, S-bilirubin, alkaline phosphatase) and urine (proteins, blood, others) sampling before sedation and after examination, heart rate (electrocardiography) and oxygen saturation (pulse oximetry) during examination, adverse events, and efficacy parameters were analyzed.

RESULTS

In the contrast group, 18 (51.4%) children had 31 abnormal changes in one or more of the safety parameters and vital signs. In the control group there were 16 (80.0%) children with 19 abnormal changes. Gadodiamide injection had no negative influence on the safety parameters. No serious adverse events occurred, and only three clinically relevant adverse events (elevation of S-ALAT and S-ASAT, elevation of bilirubin) in two patients in the contrast group and one event (vomiting) in one patient in the control group were documented. The benefit of the contrast medium was clearly shown for all evaluated parameters.

CONCLUSIONS

Gadodiamide injection is safe, well tolerated, and effective in infants younger than 6 months of age.

Intestinal obstruction in the elderly. Prognostic factors of mortality

OBJECTIVES

To analyze mortality-related factors in elderly patients who were operated on for intestinal obstruction, and to determine whether advanced age worsened the morbidity and mortality rates.

METHODS

In this prospective study we analyzed 188 patients older than 69 years who were operated on for intestinal obstruction. Group 1 consisted of 82 patients aged between 70 and 79 years, and group 2 consisted of 106 patients aged 80 years and older. We compared the distribution of clinical features and outcomes between the two groups, and determined factors related with mortality (chi-squared test with Yates' correction, Student's t test and multiple logistic regression analysis).

RESULTS

The incidence of heart disease was 11% in group 1 and 35% in group 1 (p = 0.0003). There was no difference between the groups in any of the other factors analyzed. Univariate analysis identified as mortality-related factors perianesthetic risk (American Society of Anesthesiologists' Physical Status classification) (p = 0.0005), presence of metastases (p = 0.0001) and delay in surgery (t value = 3.043, p = 0.0027).

CONCLUSIONS

Mortality due to surgery for intestinal obstruction in elderly patients is related to perianesthetic risk and delay in surgery. Older age does not increase the morbidity or mortality rates for this type of surgery.

The relationship between placental histology and cervical ultrasonography in women at risk for pregnancy loss and spontaneous preterm birth

OBJECTIVE

Our objective was to determine whether there were any differences in the placental lesions of high-risk patients with versus without ultrasonographic evidence of cervical shortening between 15 and 24 weeks' gestation.

STUDY DESIGN

Women who were at risk for pregnancy loss and spontaneous preterm birth were followed by serial transvaginal cervical ultrasonography with transfundal pressure between 15 and 24 weeks' gestation. Two groups of women were identified: those in whom progressive cervical shortening developed to below 2 cm, either spontaneously or induced by transfundal pressure, and those in whom it did not. A perinatal pathologist who was blinded to the pregnancy outcome retrospectively examined placental histologic slides. The histologic placental lesions were categorized as acute or chronic inflammatory lesions, decidual vascular lesions, and coagulation-related lesions.

RESULTS

There were 278 women who were followed during the study. Placentas were submitted for histologic examination in 189 cases (125 singleton, 45 twin, and 19 triplet gestations). There were 72 pregnancies with and 117 pregnancies without an ultrasonographic diagnosis of cervical shortening, respectively. Overall, there were significantly more acute inflammatory lesions in patients in whom cervical shortening developed, as determined by ultrasonographic examination. However, there were significantly more decidual vascular lesions in women in whom cervical shortening did not develop. When we examined the distribution of the placental histologic lesions in the 64 cases of multiple gestations, the only significant finding was again a greater frequency of acute inflammatory lesions in patients in whom cervical shortening developed. There was no difference in the distribution of the placental histologic lesion categories among women treated with bed rest versus cervical cerclage because of the ultrasound diagnosis of cervical shortening.

CONCLUSION

Acute inflammatory lesions of the placenta were more frequent in patients with second-trimester cervical shortening. These findings support that patients with cervical shortening in the second trimester are prone to acute placental inflammation.

[Surgery unit for epilepsy]

INTRODUCTION

Only few medically refractory epileptic patients are evaluated for surgical treatment, in spite of the good results obtained at the Centers where epilepsy surgery is performed.

OBJECTIVE

We are presenting the way the Gregorio Marañón Hospital Epilepsy Surgery Unit functions and their casuistry.

PATIENTS AND METHODS

This Unit is composed by members of the Services of Neurosurgery, Neurology, Neurophysiology, Neuroradiology, Psychology, Neuropediatry, Nuclear Medicine and Neuroanestesiology. Patients are studied by means of protocols.

RESULTS

Twenty cases were operated upon. The procedures were temporal lobectomy in 9 cases, amygdalo-hipocampectomy in 4, frontal lobectomy in 3, frontal topectomy in 2, partial hemispherectomy in 1 and vagal nerve stimulation in 1. In 16 of the 19 surgery specimen there were some pathological abnormalities. In the short follow-up 13 patients are seizures free experience significant improvement.

Colorectal resection and primary anastomosis in patients aged 70 and older: prospective study

OBJECTIVE

To assess the differences in morbidity, mortality, and other immediate postoperative results of colorectal resection with primary anastomosis in relation to age.

DESIGN

Prospective study.

SETTING

District hospital, Spain.

SUBJECTS

316 consecutive patients who required colorectal resection with primary anastomosis between 1991 and 1995, 155 of whom were aged <70 years and 161 who were 70 years or more.

MAIN OUTCOME MEASURES

Mortality, morbidity, and hospital stay.

RESULTS

116 patients aged <70 (75%) were American Society of Anaesthesiologists (ASA) grades I-II compared with 82 (51%) aged > or =70.33 of the younger patients (21%) and 49 of the older (30%) developed complications. The anastomotic leak rate was 14% (n = 21) in the younger group and 16% (n = 26) among those aged > or =70. Median hospital stay was 14 and 15 days, respectively (ranges 8-81 and 1-120). 4 died (3%) among those aged <70 compared with 17 (11%) in the older group (p = 0.009, chi square 6.9). Mortality for elective resections was 6% (15/263) compared with 11% (6/53) for emergencies. There were no significant differences in mortality according to ASA grade between age groups.

CONCLUSIONS

People aged 70 or more are not a high risk group for colorectal resection and primary anastomosis as a result of their age alone. Mortality and morbidity depend more on ASA grade and whether the operation was elective or emergency.