Brain tissue heterotopia in the nasopharynx. Contribution of MRI to assessment of extension.

The authors report two cases of brain tissue heterotopia in the nasopharynx, without other malformations and, in one of the cases, with a persistent craniopharyngeal canal opening onto the heterotopia. This exceptional malformation is very similar to brain heterotopia in the nose, or "nasal glioma", which is more frequent and less diversified at histology. The malformation is revealed by obstruction of the pharynx with respiratory distress immediately after birth or during the first weeks of life. Total surgical excision provides cure without sequelae. The diagnosis is based on histology. MRI is essential to the diagnostic and pretherapeutic evaluation, notably to avoid missing an ectopic hypophysis, but it is insufficient to diagnose a sphenoidal meningoencephalocele.     

Generation and comparative analysis of approximately 3.3 Mb of mouse genomic sequence orthologous to the region of human chromosome 7q11.23 implicated in Williams syndrome.

Williams syndrome is a complex developmental disorder that results from the heterozygous deletion of a approximately 1.6-Mb segment of human chromosome 7q11.23. These deletions are mediated by large (approximately 300 kb) duplicated blocks of DNA of near-identical sequence. Previously, we showed that the orthologous region of the mouse genome is devoid of such duplicated segments. Here, we extend our studies to include the generation of approximately 3.3 Mb of genomic sequence from the mouse Williams syndrome region, of which just over 1.4 Mb is finished to high accuracy. Comparative analyses of the mouse and human sequences within and immediately flanking the interval commonly deleted in Williams syndrome have facilitated the identification of nine previously unreported genes, provided detailed sequence-based information regarding 30 genes residing in the region, and revealed a number of potentially interesting conserved noncoding sequences. Finally, to facilitate comparative sequence analysis, we implemented several enhancements to the program, including the addition of links from annotated features within a generated percent-identity plot to specific records in public databases. Taken together, the results reported here provide an important comparative sequence resource that should catalyze additional studies of Williams syndrome, including those that aim to characterize genes within the commonly deleted interval and to develop mouse models of the disorder.     

Influence of Verapamil and Cyclosporin A on bile acid metabolism and transport in rat liver slices.

Verapamil (V) is a specific inhibitor of the P-glycoprotein (mdr1) in the hepatocyte canalicular membrane. Cyclosporin A (CsA) as an essential immunosuppressive drug has potentially cholestatic adverse effects on the liver, but increases the expression of mdr1. In precision-cut liver slices from 34- to 40-day-old male Wistar rats 26 individual free and conjugated bile acids (BAs) as markers of hepatic transport and synthesis function were analysed after 4 h incubation with V (100 microM) or CsA (5 microM) in Krebs-Henseleit buffer. Some slices were loaded with cholic acid (CA 5 microM) or tauro-ursodeoxycholic acid (T-UDCA 5 microM) to investigate the V and CsA effects under conditions of BA supplementation. BAs were determined in tissue and medium by HPLC with postcolumn derivatisation and fluorescence detection. V and CsA, influencing different targets in BA transport, enhanced slice concentrations of T- and glyco- (G-) conjugated CA only when exogenous CA was given additionally. This BA accumulation in tissue is more reflected at decreased medium concentrations of these BAs after V and CsA incubations. Both V and CsA also inhibited CA uptake into the slices. The acidic chenodeoxycholic acid (CDCA) synthesis pathway is disturbed: T- and G-CDCA concentrations are diminished in slices and medium after V and CsA incubations. T-UDCA plus V or CsA enhanced not only its own slice concentration but also the concentration of the trihydroxylated tauro-muricholic acid (T-beta-MCA), reflecting the conversion of the accumulated dihydroxylated T-UDCA into the T-beta-MCA. The similar effects of V and CsA on BA transport and metabolism can be explained by mdr1 mediated disturbances of cellular ATP transport rather than by inhibition of individual BA transporters.     

Testosterone suppresses protective responses of the liver to blood-stage malaria

Testosterone induces a lethal outcome in otherwise self-healing blood-stage malaria caused by Plasmodium chabaudi. Here, we examine possible testosterone effects on the antimalaria effectors spleen and liver in female C57BL/6 mice. Self-healing malaria activates gating mechanisms in the spleen and liver that lead to a dramatic reduction in trapping activity, as measured by quantifying the uptake of 3-mum-diameter fluorescent polystyrol particles. However, testosterone delays malaria-induced closing of the liver, but not the spleen. Coincidently, testosterone causes an approximately 3- to 28-fold depression of the mRNA levels of nine malaria-responsive genes, out of 299 genes tested, only in the liver and not in the spleen, as shown by cDNA arrays and Northern blotting. Among these are the genes encoding plasminogen activator inhibitor (PAI1) and hydroxysteroid sulfotransferase (STA2). STA2, which detoxifies bile acids, is suppressed 10-fold by malaria and an additional 28-fold by testosterone, suggesting a severe perturbation of bile acid metabolism. PAI1 is protective against malaria, since disruption of the PAI1 gene results in partial loss of the ability to control the course of P. chabaudi infections. Collectively, our data indicate that the liver rather than the spleen is a major target organ for testosterone-mediated suppression of resistance against blood-stage malaria.     

Identification of a novel mycobacterial histone H1 homologue (HupB) as an antigenic target of pANCA monoclonal antibody and serum immunoglobulin A from patients with Crohn's disease

pANCA is a marker antibody associated with inflammatory bowel disease (IBD), including most patients with ulcerative colitis and a subset with Crohn's disease. This study addressed the hypothesis that pANCA reacts with an antigen(s) of microbial agents potentially relevant to IBD pathogenesis. Using a pANCA monoclonal antibody, we have previously identified the C-terminal basic random-coil domain of histone H1 as a pANCA autoantigen. BLAST analysis of the peptide databases revealed H1 epitope homologues in open reading frames of the Mycobacterium tuberculosis genome. Western analysis of extracts from six mycobacterial species directly demonstrated reactivity to a single, conserved approximately 32-kDa protein. Direct protein sequencing, followed by gene cloning, revealed a novel 214-amino-acid protein, an iron-regulated protein recently termed HupB. Sequence analysis demonstrated its homology with the mammalian histone H1 gene family, and recombinant protein expression confirmed its reactivity with the 5-3 pANCA monoclonal antibody. Binding activity of patient serum immunoglobulin G (IgG) to HupB did not correlate with reactivity to histone H1 or pANCA, indicating the complex character of the pANCA antigen. However, anti-HupB IgA was strongly associated with Crohn's disease (P < 0.001). These findings indicate that the 5-3 pANCA monoclonal antibody detects a structural domain recurrent among mycobacteria and cross-reactive with a DNA-binding domain of histone H1. The association of HupB-binding serum IgA with IBD provides new evidence for the association of a mycobacterial species with Crohn's disease.     

Optimal dietary therapy of long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency

Current dietary therapy for long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) or trifunctional protein (TFP) deficiency consists of fasting avoidance, and limiting long-chain fatty acid (LCFA) intake. This study reports the relationship of dietary intake and metabolic control as measured by plasma acylcarnitine and organic acid profiles in 10 children with LCHAD or TFP deficiency followed for 1 year. Subjects consumed an average of 11% of caloric intake as dietary LCFA, 11% as MCT, 12% as protein, and 66% as carbohydrate. Plasma levels of hydroxypalmitoleic acid, hydroxyoleic, and hydroxylinoleic carnitine esters positively correlated with total LCFA intake and negatively correlated with MCT intake suggesting that as dietary intake of LCFA decreases and MCT intake increases, there is a corresponding decrease in plasma hydroxyacylcarnitines. There was no correlation between plasma acylcarnitines and level of carnitine supplementation. Dietary intake of fat-soluble vitamins E and K was deficient. Dietary intake and plasma levels of essential fatty acids, linoleic and linolenic acid, were deficient. On this dietary regimen, the majority of subjects were healthy with no episodes of metabolic decompensation. Our data suggest that an LCHAD or TFP-deficient patient should adhere to a diet providing age-appropriate protein and limited LCFA intake (10% of total energy) while providing 10-20% of energy as MCT and a daily multi-vitamin and mineral (MVM) supplement that includes all of the fat-soluble vitamins. The diet should be supplemented with vegetable oils as part of the 10% total LCFA intake to provide essential fatty acids.     

Changed visuomotor transformations during and after prolonged microgravity

A series of step-tracking experiments was conducted before, during, and after a 3-week space mission to assess the effects of prolonged microgravity on a non-postural motor-control task. In- and post-flight accuracy was affected only marginally. However, kinematic analyses revealed a considerable change in the underlying movement dynamics: too-small force and, thus, too-low velocity in the first part of the movements was mainly compensated by lengthening the deceleration phase of the primary movement, so that accuracy was regained at its end. The observed in-flight decrements in peak velocity and peak acceleration point to an underestimation of mass, in agreement with the re-interpretation hypothesis of Bock et. al. Post-flight no reversals of the in-flight changes (negative aftereffects) were found. Instead, there was a general slowing down, which could be due to post-flight physical exhaustion.     

Extrinsic versus intrinsic cues in avian paraxial mesoderm patterning and differentiation.

Somitic and head mesoderm contribute to cartilage and bone and deliver the entire skeletal musculature. Studies on avian somite patterning and cell differentiation led to the view that these processes depend solely on cues from surrounding tissues. However, evidence is accumulating that some developmental decisions depend on information within the somitic tissue itself. Moreover, recent studies established that head and somitic mesoderm, though delivering the same tissue types, are set up to follow their own, distinct developmental programmes. With a particular focus on the chicken embryo, we review the current understanding of how extrinsic signalling, operating in a framework of intrinsically regulated constraints, controls paraxial mesoderm patterning and cell differentiation.     

Apoptosis in endometrial glandular and stromal cells in women with and without endometriosis

BACKGROUND: The aetiology of endometriosis is unknown. Ectopic dissemination of the endometrial cells gives origin to endometriotic lesions, but occurs in women with and without endometriosis. It has been suggested that increased ectopic cell survival facilitates their implantation. The objectives of this study were to evaluate endometrial apoptosis in women with endometriosis according to: (i) cyclic changes, (ii) glandular and stromal contribution, and (iii) stage of the disease. METHODS: The subjects were women undergoing diagnostic laparoscopy and endometrial biopsies for suspected endometriosis. Spontaneous apoptosis was evaluated using TdT-mediated dUTP-biotin nick end-labelling (TUNEL) assay. Apoptotic cells per 10 mm(2) (apoptotic index) in an area of 10-50 mm(2) in 5 microm endometrial tissue sections were counted and location of these cells was recorded. RESULTS: The apoptotic index in glandular epithelium was lower in endometriosis than controls (26.0 +/- 5.5 versus 51.2 +/- 9.7, P = 0.03) but not in the stroma (36.3 +/- 6.4 versus 48.4 +/- 11.3, NS). In controls, apoptosis was highest during the late secretory/menstrual and early proliferative phases and cyclic variability was apparent. In endometriosis, this cyclic variability was lost. There was a trend toward decreased apoptosis with increasing stage of the disease, but the differences lacked statistical significance. CONCLUSIONS: Spontaneous apoptosis is decreased in the endometrial glands in women with endometriosis, especially during late secretory/menstrual and early proliferative phases of the cycle. This may indicate increased viability of endometrial cells shed during menses, facilitating their ectopic survival and implantation.