Aldehyde dehydrogenase-1a1 induces oncogene suppressor genes in B cell populations.

The deregulation of B cell differentiation has been shown to contribute to autoimmune disorders, hematological cancers, and aging. We provide evidence that the retinoic acid-producing enzyme aldehyde dehydrogenase 1a1 (Aldh1a1) is an oncogene suppressor in specific splenic IgG1(+)/CD19(-) and IgG1(+)/CD19(+) B cell populations. Aldh1a1 regulated transcription factors during B cell differentiation in a sequential manner: 1) retinoic acid receptor alpha (Rara) in IgG1(+)/CD19(-) and 2) zinc finger protein Zfp423 and peroxisome proliferator-activated receptor gamma (Pparg) in IgG1(+)/CD19(+) splenocytes. In Aldh1a1(-/-) mice, splenic IgG1(+)/CD19(-) and IgG1(+)/CD19(+) B cells acquired expression of proto-oncogenic genes c-Fos, c-Jun, and Hoxa10 that resulted in splenomegaly. Human multiple myeloma B cell lines also lack Aldh1a1 expression; however, ectopic Aldh1a1 expression rescued Rara and Znf423 expressions in these cells. Our data highlight a mechanism by which an enzyme involved in vitamin A metabolism can improve B cell resistance to oncogenesis.

Neurodevelopmental scaling is a major driver of brain-behavior differences in temperament across dog breeds.

Behavioral traits like aggression, anxiety, and trainability differ significantly across dog breeds and are highly heritable. However, the neural bases of these differences are unknown. Here we analyzed structural MRI scans of 62 dogs in relation to breed-average scores for the 14 major dimensions in the Canine Behavioral Assessment and Research Questionnaire, a well-validated measure of canine temperament. Several behavior categories showed significant relationships with morphologically covarying gray matter networks and regional volume changes. Networks involved in social processing and the flight-or-fight response were associated with stranger-directed fear and aggression, putatively the main behaviors under selection pressure during wolf-to-dog domestication. Trainability was significantly associated with expansion in broad regions of cortex, while fear, aggression, and other "problem" behaviors were associated with expansion in distributed subcortical regions. These results closely overlapped with regional volume changes with total brain size, in striking correspondence with models of developmental constraint on brain evolution. This suggests that the established link between dog body size and behavior is due at least in part to disproportionate enlargement of later-developing regions in larger brained dogs. We discuss how this may explain the known correlation of increasing reactivity with decreasing body size in dogs.

Immunomodulatory effects of plasminogen activators on hepatic fibrogenesis.

Tissue-type plasminogen activators (tPA) and urokinase-type plasminogen activators (uPA) are involved in liver repair. We examined the potential immunomodulatory actions of uPA, tPA and uPA-receptor (uPAR) in carbon-tetrachloride-induced hepatic fibrosis in wild-type (WT), tPA-/-, uPA-/- and uPAR-/- mice. Carbon-tetrachloride treatment increased fibrosis in four groups but significantly less in three knock-out models. Serum cytokines and intrahepatic T cells elevated significantly following fibrosis process in WT animals but not in the knock-out groups. In culture, uPA increased lymphocyte proliferation significantly in WT and uPA-/- but not uPAR-/- animals. Following uPA exposure in vivo, there was CD8 predominance. To isolate uPA's effect on lymphocytes, WT mice were irradiated sublethally and then reconstituted with WT or uPA-/- lymphocytes. In these animals fibrosis was decreased and T cells were reduced in the uPA-/- recipients. Based on these data we postulate that plasminogen activators affect fibrosis in part by liver-specific activation of CD8 subsets that govern the fibrogenic activity of hepatic stellate cells.

The crystal structure of the malic enzyme from Candidatus Phytoplasma reveals the minimal structural determinants for a malic enzyme.

Phytoplasmas are wall-less phytopathogenic bacteria that produce devastating effects in a wide variety of plants. Reductive evolution has shaped their genome, with the loss of many genes, limiting their metabolic capacities. Owing to the high concentration of C4 compounds in plants, and the presence of malic enzyme (ME) in all phytoplasma genomes so far sequenced, the oxidative decarboxylation of L-malate might represent an adaptation to generate energy. Aster yellows witches'-broom (Candidatus Phytoplasma) ME (AYWB-ME) is one of the smallest of all characterized MEs, yet retains full enzymatic activity. Here, the crystal structure of AYWB-ME is reported, revealing a unique fold that differs from those of `canonical' MEs. AYWB-ME is organized as a dimeric species formed by intertwining of the N-terminal domains of the protomers. As a consequence of such structural differences, key catalytic residues such as Tyr36 are positioned in the active site of each protomer but are provided by the other protomer of the dimer. A Tyr36Ala mutation abolishes the catalytic activity, indicating the key importance of this residue in the catalytic process but not in the dimeric assembly. Phylogenetic analyses suggest that larger MEs (large-subunit or chimeric MEs) might have evolved from this type of smaller scaffold by gaining small sequence cassettes or an entire functional domain. The Candidatus Phytoplasma AYWB-ME structure showcases a novel minimal structure design comprising a fully functional active site, making this enzyme an attractive starting point for rational genetic design.

HLA class II-restricted binding of muramyl peptides to B lymphocytes of normal and narcoleptic subjects.

The propensity for narcolepsy, a clinical sleep disorder of unknown etiology, is virtually totally included within the HLA-DR2,DQw1 (DRw15,DQw6) phenotype. The disorder is characterized by decreased sleep latency, early onset of rapid eye movement sleep, and a paucity of nocturnal slow-wave sleep. Muramyl peptides, naturally occurring bacterial cell wall peptidoglycans, potently enhance the duration and amplitude of slow-wave sleep in animals, bind to murine mononuclear cells, and exhibit a major histocompatibility complex-restricted immunoadjuvant effect in mice. We examined the binding of muramyl peptides to peripheral blood mononuclear leukocytes of HLA-typed normal (n = 13) and narcoleptic (n = 10) subjects. Muramyl peptides bound specifically and with high affinity to normal B- but not T-lymphocyte-enriched preparations. There was no significant specific binding to B-cell-enriched preparations from narcoleptic patients. Furthermore, B-lymphocyte-enriched preparations of normal individuals who had the HLA-DR2,DQw1 phenotype (n = 8) exhibited a lower level of specific binding than those of normals who did not have this phenotype (n = 5, p less than 0.001). These observations are an additional indication of the relevance of muramyl peptides to slow-wave sleep and provide a basis for a better understanding of the relation between narcolepsy and the MHC at the biochemical level.

Insulin receptor substrate protein p53 localization in rats suggests mechanism for specific polyglutamine neurodegeneration.

Dentatorubral-pallidoluysian atrophy (DRPLA) is a neurodegenerative disease that results from the expansion of an unstable CAG repeat within the coding regions of the DRPLA gene. Recently it was shown that the DRPLA gene product, atrophin-1, interacts with the human insulin receptor tyrosine kinase substrate protein, IRSp53. We have isolated rat and mouse cDNA clones for IRSp53 and determined expression patterns in rat central nervous system. In situ hybridization analysis revealed enriched IRSp53 mRNA expression in rat forebrain structures, including the cerebral cortex (layers II/III, V and VI), striatum, hippocampus and olfactory bulb. IRSp53 hybridization signals were also detected in the cerebellum, subthalamic nucleus, pons, amygdala and hypothalamus. These findings support the idea that insulin and insulin growth factor-1 have a role in neurotransmission, one that is regionally specific. The expression of IRSp53 in regions similar to those that degenerate in DRPLA supports the notion that IRSp53 is a relevant atrophin-1 binding protein and may provide a mechanism for region-specific neurodegeneration.

Evolutionarily distinct classes of S27 ribosomal proteins with differential mRNA expression in rat hypothalamus.

Using an in situ hybridization screen for cDNA clones of brain region-specific mRNAs, we isolated a rat transcript that encodes a ribosomal protein S27. Searching GenBank DNA databases, we found two S27 protein isoforms. One isoform, encoded by multiple genes, is extant in archaea and eukarya, but not bacteria. The second isoform appears to be recently evolved because it has been identified only in mammals. Multiple transcripts encode each isoform and exhibit different tissue expression patterns throughout rat brain and periphery, with abundant expression in the hypothalamus. In situ hybridization studies revealed predominant expression of S27(1) in distinct hypothalamic nuclei, such as the paraventricular, supraoptic, suprachiasmatic, arcuate, and circularis nuclei, whereas expression of S27(2) mRNA was discretely expressed in select neurons of the periventricular and supraoptic nuclei. Combined with the genetic evidence that S27 has extraribosomal functions in plants, the complexity of S27 biology observed here may suggest auxiliary functions for S27 proteins in the mammalian nervous system.

Novel Gq alpha isoform is a candidate transducer of rhodopsin signaling in a Drosophila testes-autonomous pacemaker.

DGq is the alpha subunit of the heterotrimeric GTPase (G alpha), which couples rhodopsin to phospholipase C in Drosophila vision. We have uncovered three duplicated exons in dgq by scanning the GenBank data base for unrecognized coding sequences. These alternative exons encode sites involved in GTPase activity and G beta-binding, NorpA (phospholipase C)-binding, and rhodopsin-binding. We examined the in vivo splicing of dgq in adult flies and find that, in all but the male gonads, only two isoforms are expressed. One, dgqA, is the original visual isoform and is expressed in eyes, ocelli, brain, and male gonads. The other, dgqB, has the three novel exons and is widely expressed. Remarkably, all three nonvisual B exons are highly similar (82% identity at the amino acid level) to the Gq alpha family consensus, from Caenorhabditis elegans to human, but all three visual A exons are divergent (61% identity). Intriguingly, we have found a third isoform, dgqC, which is specifically and abundantly expressed in male gonads, and shares the divergent rhodopsin-binding exon of dgqA. We suggest that DGqC is a candidate for the light-signal transducer of a testes-autonomous photosensory clock. This proposal is supported by the finding that rhodopsin 2 and arrestin 1, two photoreceptor-cell-specific genes, are also expressed in male gonads.

Total anomalous pulmonary venous connection.

Repair of total anomalous pulmonary venous connection was performed on 31 patients aged 12 days to 14 years (18 less than 6 months). The connection type was supracardiac in 20 cases, cardiac in nine, infracardiac in one case and mixed in one. Deep hypothermia and circulatory arrest were used in 23 cases (74%). In supracardiac type cases the atrial septal defect was closed through the left atriotomy, without enlargement of the left atrium. Extubation in the operating room was possible in 26 cases (84%). Three patients (9.6%) died, one (with connection to the coronary sinus) soon after operation, due to a management error, another (with connection to the right superior vena cava) of pulmonary edema, and an infant with mixed-type connection 1 week postoperatively, presumably from an arrhythmia. No patient required reoperation because of late pulmonary venous stenosis. There were no late deaths. The technique of elevating the cardiac apex provided excellent exposure in the supracardiac and infracardiac types. Progressively earlier referral during the study period facilitated prompt operation and improved patient salvage.

Maintenance treatment with depot opioid antagonists in subcutaneous implants: an alternative in the treatment of opioid dependence.

A report is presented of treatment of 156 patients (male 98%) with opioid dependence (ICD-10 criteria) using a maintenance programme with depot opioid antagonists (naltrexone) as subcutaneous implants, started after an outpatient rapid antagonization regimen. The retention index in the treatment was from 80% in the sixth month, and 65% after one year. The patients were followed-up for 1 year after discharge. For 6 months after discharge 55.4% were still returning for follow-up visits and 20.8% after 1 year, all of them remaining abstinent to opioids. It is concluded that the programme is safe for the patients and shows a better retention index than programmes using oral antagonists, with an improved compliance (negative urine analysis) compared to the latter.

24-Hour opiate detoxification and antagonist induction at home--the 'Asturian method': a report on 1368 procedures.

The technique of domiciliary rapid opiate detoxification (ROD) developed in Asturias since 1994 enables patients dependent on heroin and/or methadone (or other opiates) to start antagonist maintenance with a full dose of naltrexone (50 mg) and largely recover from the acute opiate withdrawal syndrome in a few hours at home without direct medical or nursing involvement. Detailed information on 1368 procedures is presented but in Asturias, over 3000 procedures have been completed to date without any deaths or serious medical or psychiatric complications. We also describe some recent modifications to the procedure involving the use of octreotide as an antidiarrhoeal and the insertion of subcutaneous naltrexone implants to prevent early relapse. Rather than domiciliary ROD, we think the procedure is more usefully conceptualized as domiciliary rapid antagonist induction (RAI), because treatment with well-supervised naltrexone is known to be effective in reducing relapse rates. Now that controlled studies uniformly describe greatly increased rates of transfer to naltrexone maintenance treatment following RAI, compared with conventional slower withdrawal and naltrexone induction procedures, it is important that the safety, acceptability and simplicity of this 'Asturian' RAI/ROD technique become more widely known.

[Study of effectiveness of craving control with topiramate in patients with substance dependence disorders]. / Estudio de la efectividad del control del craving con topiramato en pacientes con trastornos por dependencia de sustancias.

INTRODUCTION: Effectiveness and tolerability of topiramate at 3 and 6 months was assessed in patients requesting dehabituation programs. METHODS: Observational, prospective, national and multicenter study of 6 months, in patients on treatment with topiramate, who fulfilled criteria for dependence of opiates according to ICD-10 participating in therapeutic programs of dehabituation, without concomitant psychiatric illnesses and any responsible relative. Main measures of effectiveness were retention rates, alcohol consumption and other illicit drugs by urine tests (opiates, cannabis, cocaine) and treatment needs by EuropASI scale. Other parameters were HAM-D, DAS-SV and SF-36. RESULTS: Patients with consumption by urine tests decreased from 94.1 % (n = 64) at baseline to 39.6 % (n = 19) after 6 months of treatment, as was seen by means of the mean score in EuropASI scale, for all substances except methadone. No consumption was accompanied by a low rate of relapse of 33.3 % at 6 months. Twenty one patients had adverse reactions (28 %). The most frequent adverse reactions were somnolence (n = 9; 12 %), paraesthesia (n = 5; 6.7 %) and depression (n = 4; 5.3 %). CONCLUSIONS: In real clinical practice, topiramate showed a good response with a relevant decrease of percent of patients with abuse or consumption, and a satisfactory tolerability profile for the treatment of patients with dependence on heroine, cocaine, and other opiates, showing better outcomes than those obtained in previous trials.