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Recent research on familial dysautonomia (FD) has focused on the development of therapeutics that facilitate the production of the correctly spliced, exon 20-containing, transcript in cells and individuals bearing the splice-altering, FD-causing mutation in the elongator acetyltransferase complex subunit I (ELP1) gene. We report here the ability of carnosol, a diterpene present in plant species of the Lamiaceae family, including rosemary, to enhance the cellular presence of the correctly spliced ELP1 transcript in FD patient-derived fibroblasts by upregulating transcription of the ELP1 gene and correcting the aberrant splicing of the ELP1 transcript. Carnosol treatment also elevates the level of the RNA binding motif protein 24 (RBM24) and RNA binding motif protein 38 (RBM38) proteins, two multifunctional RNA-binding proteins. Transfection-mediated expression of either of these RNA binding motif (RBMs) facilitates the inclusion of exon 20 sequence into the transcript generated from a minigene-bearing ELP1 genomic sequence containing the FD-causing mutation. Suppression of the carnosol-mediated induction of either of these RBMs, using targeting siRNAs, limited the carnosol-mediated inclusion of the ELP1 exon 20 sequence. Carnosol treatment of FD patient peripheral blood mononuclear cells facilitates the inclusion of exon 20 into the ELP1 transcript. The increased levels of the ELP1 and RBM38 transcripts and the alternative splicing of the sirtuin 2 (SIRT2) transcript, a sentinel for exon 20 inclusion in the FD-derived ELP1 transcript, are observed in RNA isolated from whole blood of healthy adults following the ingestion of carnosol-containing rosemary extract. These findings and the excellent safety profile of rosemary together justify an expedited clinical study of the impact of carnosol on the FD patient population.

Long-distance pollen dispersal is critical for gene flow in plant populations, yet pollen dispersal patterns in urban habitats such as green roofs have not been extensively studied. Pollen dispersal patterns typically are assessed either by fitting non-linear models to the relationship between the degree of pollen dispersal and distance to the pollen source (i.e., curve fitting), or by fitting probability density functions (PDFs) to pollen dispersal probability histograms (i.e., PDF fitting). Studies using curve fitting typically report exponential decay patterns in pollen dispersal. However, PDF fitting typically produces more fat-tailed distributions, suggesting the exponential decay may not be the best fitting model. Because the two approaches may yield conflicting results, we used both approaches to examine pollen dispersal patterns in the wind-pollinated Amaranthus tuberculatus and the insect-pollinated Solanum lycopersicum at two green roof and two ground-level sites in the New York (NY, United States) metropolitan area. For the curve fitting analyses, the exponential decay and inverse power curves provided good fits to pollen dispersal patterns across both green roof and ground-level sites for both species. Similar patterns were observed with the PDF fitting analyses, where the exponential or inverse Gaussian were the top PDF at most sites for both species. While the curve fitting results are consistent with other studies, the results differ from most studies using PDF fitting, where long-distance pollen dispersal is more common than we observed. These results highlight the need for further research to compare curve and PDF fitting for predicting pollen dispersal patterns. And, critically, while long-distance pollen dispersal may be an important component of overall pollen dispersal for A. tuberculatus and S. lycopersicum in both urban green roof and ground-level sites, our results suggest it potentially may occur to a lesser extent compared with plants in less-urban areas.

The successful completion of the Human Genome Project led to the discovery of the molecular basis of thousands of genetic disorders. The identification of the mutations that cause familial dysautonomia (FD), an autosomal recessive disorder that impacts sensory and autonomic neurons, was aided by the release of the human DNA sequence. The identification and characterization of the genetic cause of FD have changed the natural history of this disease. Genetic testing programs, which were established shortly after the disease-causing mutations were identified, have almost completely eliminated the birth of children with this disorder. Characterization of the principal disease-causing mutation has led to the development of therapeutic modalities that ameliorate its effect, while the development of mouse models that recapitulate the impact of the mutation has allowed for the in-depth characterization of its impact on neuronal development and survival. The intense research focus on this disorder, while clearly benefiting the FD patient population, also serves as a model for the positive impact focused research efforts can have on the future of other genetic diseases. Here, we present the research advances and scientific breakthroughs that have changed and will continue to change the natural history of this centuries-old genetic disease.

We present some improvements on interpolation based control (IC) for linear discrete-time systems with polyhedral constraints on the control and the states variables. The plant may be uncertain, time-varying, and subject to bounded disturbances. Roughly speaking, IC approach is based on the interpolation between an inner and an outer controller. The extension presented here is twofold. On the one hand, the IC approach is extended to deal with higher order inner controllers, making it e.g. possible to incorporate integral action in a vicinity of the origin. On the other hand, this paper presents a modification that better exploits the control signal range. As with previous IC strategies, the presented method demands relatively low online computational resources, and is applicable also to uncertain plants. The benefits of the improved scheme are illustrated in some examples.

Premise Pollen dispersal plays a critical role in gene flow of seed plants. Most often, pollen dispersal is measured using paternity assignment. However, this approach can be time-consuming because it typically entails genotyping all pollen donors, receptors, and offspring at several molecular markers. Methods We developed a faster, simpler protocol to track paternity, using pollen receptors and grouped pollen donors that possess rare alleles. We tested this approach using wind-pollinated Amaranthus tuberculatus and insect-pollinated Solanum lycopersicum. After screening potential markers for rare alleles, we grew both species in experimental arrays under field conditions. Results All tested A. tuberculatus seeds and 97% of S. lycopersicum fruits could be assigned to the grouped pollen donors using each of two markers. From these results, we could infer paternity of untested offspring and assess pollen dispersal patterns in each array. Discussion By combining rare alleles and grouped pollen donors, we could assess pollen dispersal for both species and across all arrays after genotyping a small number of pollen donors and a representative subset of offspring. While directly applicable to A. tuberculatus and S. lycopersicum, this approach could be used in other species to assess pollen dispersal under field conditions.

Premise Pollen dispersal, the main component of overall plant gene flow, generally decreases with increasing distance from the pollen source, but the pattern of this relationship may differ among sites. Although site-based differences in pollen dispersal may lead to over- or underestimation of gene flow, no studies have investigated pollen dispersal patterns among differing urban site types, despite the incongruent range of habitats in urban areas. Methods We used paternity assignment to assess pollen dispersal patterns in a wind-pollinated species (waterhemp; Amaranthus tuberculatus) and in an insect-pollinated species (tomato; Solanum lycopersicum) in experimental arrays at four disparate sites (two roof-level sites, two ground-level sites) in the New York (New York, USA) metropolitan area. Results The number of seeds or fruits, a proxy for the number of flowers pollinated, decreased with increasing distance from the pollen donors at all sites for both species. However, the mean number of Amaranthus tuberculatusseeds produced at a given distance differed two-fold among sites, while the slope of the relationship between Solanum lycopersicumfruit production and distance differed by a factor of four among sites. Conclusions Pollen dispersal patterns may differ substantially among sites, both in the amount of pollen dispersed at a given distance and in the proportional decrease in pollen dispersal with increasing distance, and these effects may act independently. Accordingly, the capacity of plant species to adapt to climate change and other selection pressures may be different from predictions based on pollen dispersal patterns at a single location.

International audience; We present a new simple approach to extend the admissible region of a saturated control law for discrete-time linear systems under state and input constraints. The approach is based on the interpolation of a given, performance driven, control law and a low-gain controller. The latter is designed such that its admissible set has maximum volume. The interpolation does not require on-line numerical optimization, and an analytical formula for the controller is given. Several numerical examples are presented to illustrate the control technique.

Osteopetrosis is a rare and heterogeneous genetic disorder characterized by dense bone mass that is a consequence of defective osteoclast function and/or development. Autosomal recessive osteopetrosis (ARO) is the most severe form and is often fatal within the first years of life; early hematopoietic stem cell transplant (HSCT) remains the only curative treatment for ARO. The majority of the ARO-causing mutations are located in the TCIRG1 gene. We report here the identification and characterization of an A to T transversion in the fourth base of the intron 2 donor splice site (c.117+4A→T) in TCIRG1, a mutation not previously seen in the Ashkenazi Jewish (AJ) population. Analysis of a random sample of individuals of AJ descent revealed a carrier frequency of approximately 1 in 350. Genotyping of five loci adjacent to the c.117+4A→T-containing TCIRG1 allele revealed that the presence of this mutation in the AJ population is due to a single founder. The identification of this mutation will enable population carrier testing and will facilitate the identification and treatment of individuals homozygous for this mutation.

F AMILIAL dysautonomia (FD, also known as Riley-Day syndrome) is a rare (1:3,700 live births) autosomal recessive disorder, largely afflicting those of Ashkenazi Jewish descent. One of five hereditary sensory and autonomic neuropathies (HSAN, type III) influencing the development and survival of varied sensory, sympathetic, and parasympathetic neurons, FD is characterized by profound autonomic dysfunction resulting in sudden hypertension, orthostatic hypotension, vomiting, and/or abnormal sweating. Autonomic instability may result in significant morbidity and mortality in the perioperative period. Recent discoveries in disease genetics and pathophysiology have lead to improved treatments for FD patients, greatly reducing the incidence of dysautonomic crises and diminishing symptoms overall. Mutations in the gene for inhibitor of light polypeptide gene enhancer in B-cells, kinase complex-associated protein (IKBKAP), causing reductions in the cellular protein IKAP, have been linked to FD. In addition, tissue concentrations of monoamine oxidase A, an enzyme involved in the metabolic transformation of norepinephrine and dopamine, are low in FD. Both tocotrienols (vitamin E family) and epigallocatechin-3-gallate (a flavonoid found in green tea) increase its cellular concentration (fig. 1). Oral tocotrienols also increase monoamine oxidase A levels in FD patients. We describe the management of a child with FD scheduled for adenoidectomy and the impact of maintaining her long-term treatment with tocotrienols and green tea extract (GTE) on her perioperative course.

Congenital amegakaryocytic thrombocytopenia (MIM #604498) (CAMT) is a rare inherited disease presenting as severe thrombocytopenia in infancy. Untreated, many CAMT patients develop aplastic anemia within the first decade of life; the only effective treatment of CAMT is bone marrow transplantation. CAMT is the result of the presence of homozygous or compound heterozygous mutations in the thrombopoietin receptor-encoding gene, MPL. We report here the identification and characterization of a founder mutation in MPL in the Ashkenazi Jewish (AJ) population. This mutation, termed c.79+2T>A, is a T to A transversion in the invariant second base of the intron 1 donor splice site. Analysis of a random sample of 2018 individuals of AJ descent revealed a carrier frequency of approximately 1 in 75. Genotyping of six loci adjacent to the MPL gene in the proband and in the 27 individuals identified as carriers of the c.79+2T>A mutation revealed that the presence of this mutation in the AJ population is due to a single founder. The observed carrier frequency predicts an incidence of CAMT in the AJ population of approximately 1 in 22,500 pregnancies. The identification of this mutation will enable population carrier testing and will facilitate the identification and treatment of individuals homozygous for this mutation.

Familial dysautonomia (FD) is an inherited, fatal, neurodegenerative disorder manifested by autonomic/hypertensive crises and cardiac instability. Patients produce little IKAP, the gene product of the affected mutated gene, and have low levels of monoamine oxidase A (MAO A), whose reduced presence appears to result in an increased accumulation of biogenic amines, which is a trigger for hypertensive crises. As ingestion of tocotrienols elevates IKAP and MAO A in FD patients, we examined their impact on the frequency of hypertensive crises and cardiac function. After 3 to 4 months of tocotrienol ingestion, approximately 80% of patients reported a significant (or = 50%) decrease in the number of crises. In a smaller group of patients, a postexercise increase in heart rate and a decrease in the QT interval were observed in the majority of participants. Based on these findings, we hypothesize that tocotrienol therapy will improve the long-term clinical outlook and survival of individuals with FD.

Familial dysautonomia (FD), a recessive neurodegenerative disease, is caused by mutations in the IKBKAP gene that result in the production of nonfunctional IKAP protein. Manifestations of FD include autonomic crises characterized by hypertension, tachycardia, diaphoresis, and vomiting. Elevated plasma levels of norepinephrine (NE) and dopamine observed during autonomic crises and an exaggerated hypertensive response to low doses of NE prompted an examination of monoamine oxidase (MAO) levels, key isoenzymes responsible for degrading biogenic and dietary monoamines, in individuals with FD. Fetal tissue homozygous for the common FD-causing mutation and peripheral blood cells of individuals with FD have reduced MAO A mRNA levels. FD-derived cells, stimulated with tocotrienols or EGCG to produce increased levels of functional IKAP, express increased amounts of MAO A mRNA transcript and protein. Administration of tocotrienol to individuals with FD results in increased expression of both functional IKAP and MAO A transcripts in their peripheral blood cells. These findings provide new insight into the pathophysiology of FD and demonstrate the value of therapeutic approaches designed to elevate cellular levels of functional IKAP and MAO A.

Familial dysautonomia (FD) is an autosomal recessive neurodegenerative disorder. The most prevalent causative mutation is a T-->C transition in a donor splice site of the IKBKAP transcript, resulting in aberrant splicing and a truncated protein. The mutation's position and leaky nature suggested that its impact might be moderated by altering the level of splice-regulating proteins. The reported ability of (-)-epigallocatechin gallate (EGCG), a polyphenol, to down-regulate the expression of hnRNP A2/B1, a trans-activating factor that encourages the use of intron-distal 5(') splice sites, prompted an evaluation of its effect on the IKBKAP transcript in FD-derived cells. EGCG reduces the level of hnRNP A2/B1 and increases the amounts of the wild-type IKBKAP-encoded transcript and functional protein. Combined treatment of cells with EGCG and tocotrienol, which upregulates IKBKAP transcription, results in a synergistic production of the functional gene product. These findings suggest the possible use of EGCG as a therapeutic modality for individuals with FD.

Familial dysautonomia (FD), a neurodegenerative genetic disorder primarily affecting individuals of Ashkenazi Jewish descent, is caused by mutations in the IKBKAP gene which encodes the IjB kinase complex-associated protein (IKAP). The more common or major mutation causes aberrant splicing, resulting in a truncated form of IKAP. Tissues from individuals homozygous for the major mutation contain both mutant and wild-type IKAP transcripts. The apparent leaky nature of this mutation prompted a search for agents capable of elevating the level of expression of the wild-type IKAP transcript. We report the ability of tocotrienols, members of the vitamin E family, to increase transcription of IKAP mRNA in FD-derived cells, with corresponding increases in the correctly spliced transcript and normal protein. These findings suggest that in vivo supplementation with tocotrienols may elevate IKBKAP gene expression and in turn increase the amount of functional IKAP protein produced in FD patients. 2003Elsevier Science (USA). All rights reserved.

In 2011, the US federal government implemented an oversight program to encourage the adoption and meaningful use of electronic health records (EHRs). Otolaryngologists may receive as much as $44,000 under Medicare or $63,750 under Medicaid as part of this law. To receive this full benefit, otolaryngologists must acquire a certified EHR and demonstrate stage 1 meaningful use requirements by the end of 2012. Furthermore, the Office of the National Coordinator for Health IT intends to advance meaningful use requirements to stage 2 (estimated to go in effect in 2014) and stage 3 requirements. This commentary discusses updated recommendations from the Academy of Otolaryngology-Head and Neck Surgery Medical Informatics Committee for implementing meaningful use of EHRs, receiving incentive payments, and preparing for potential stage 2 and stage 3 requirements.

Aging is increasingly accompanied by themes of care. While younger and fitter elderly are invited to participate in the context of voluntary activities the older take advantage of this offers. The debate on the organization of care and treatment of an aging population follows two main lines of discussion: One is on the context of social change and political necessities. While the number of aging people is increasing, welfare state security systems do not seem suitable to cope with the associated (expected) challenges. The other main line to these developments is that family support systems are precarious as less and less resources are available for the acquisition of necessary care due to an increasing focus on gainful employment. From a feminist point of view “care” is understood as a social practice that involves the whole of the paid and unpaid care work. It has to be equipped with identifiable structural conditions such as material and time resources, in both the private as well as in public spaces. This paper presents results of a qualitative research with people who are engaged as volunteers for support services for elderly in rural areas. The main question is how volunteer care manifests in and for an aging population and in which kind gender differences continue.

The autosomal recessive disorder familial dysautonomia (FD) has recently been demonstrated to be caused by mutations in the IKBKAP gene, so named because an initial report suggested that it encoded an IkB kinase complex associated protein (IKAP). Two mutations in IKBKAP have been reported to cause FD. The major mutation is a T ! C transition in the donor splice site of intron 20 and the minor mutation is a missense mutation in exon 19 that disrupts a consensus serine/threonine kinase phosphorylation site. We have characterized the cDNA sequences of the mouse, rat and rabbit IKBKAP-encoded mRNAs and determined the genomic organization and chromosomal location of mouse IKBKAP. There is significant homology in the amino acid sequence of IKAP across species and the serine/threonine kinase phosphorylation site altered in the minor FD mutation of IKAP is conserved. The mouse and human IKBKAP genes exhibit significant conservation of their genomic organization and the intron 20 donor splice site sequence, altered in the major FD mutation, is conserved in the human and mouse genes. Mouse IKBKAP is located on the central portion of chromosome 4 and maps to a region in which there is conserved linkage homology between the human and mouse genomes. The homologies observed in the human and mouse sequences should allow, through the process of homologous recombination, for the generation of mice that bear the IKBKAP mutations present in individuals with FD. The characterization of such mice should provide significant information regarding the pathophysiology of FD. q 2001 Elsevier Science B.V. All rights reserved.

The defective gene DYS, which is responsible for familial dysautonomia (FD) and has been mapped to a 0.5-cM region on chromosome 9q31, has eluded identification. We identified and characterized the RNAs encoded by this region of chromosome 9 in cell lines derived from individuals homozygous for the major FD haplotype, and we observed that the RNA encoding the IkappaB kinase complex-associated protein (IKAP) lacks exon 20 and, as a result of a frameshift, encodes a truncated protein. Sequence analysis reveals a T--C transition in the donor splice site of intron 20. In individuals bearing a minor FD haplotype, a missense mutation in exon 19 disrupts a consensus serine/threonine kinase phosphorylation site. This mutation results in defective phosphorylation of IKAP. These mutations were observed to be present in a random sample of Ashkenazi Jewish individuals, at approximately the predicted carrier frequency of FD. These findings demonstrate that mutations in the gene encoding IKAP are responsible for FD.

Mixing is a major ingredient in many industrial processes to obtain desired and uniform material properties. Nowadays, many materials, pigments, additives, gas or reactants, are mixed to create new products combining the characteristics of different raw materials to obtain specific product properties. The quality of the mixing, i.e. the uniformity of the mixture, is a key issue that will determine the morphology and the properties of the resulting compound [1, 2]. An insight in the physics of mixing is therefore necessary in order to achieve a good quality of mixing or maintain it when scaling equipment, for example. Such information can now be obtained through the numerical simulation of the transient flow in extruder components. To improve greatly the ease of obtaining such information, a new technique introduced in a finite elements software is presented. This technique simplifies the meshing, reduces the meshes needed and eliminates complex remeshing algorithms to simulate flow in screws, pumps and mixing devices. This technique is validated versus traditional simulation methods (i.e. conforming meshes). 3-D transient numerical simulations of two twin screw extruder configurations are then presented. A further quantitative comparison of their mixing behavior is developed as statistical information (of the RTD, deformations, dispersion, etc.) can be obtained to compare both configurations in a synthetic and quantitative way.

An RNA species has been identified whose nucleotide sequence is closely related to the mRNA encoding the murine interferon (IFN)-induced guanylate-binding protein-1 (mGBP1) and an mRNA encoding an isoprenylated protein that is constitutively expressed in various organs in the rat. Sequence analysis of the gene encoding this newly identified RNA reveals that in its 5'-region it is identical to a DNA fragment reported to represent the 5'-region of a gene termed mGBP2. In light of this homology, we term this newly identified gene product mGBP2. mGBP2 is inducible following IFN treatment in animals bearing Gbp1a alleles, in which mGBP1 is transcriptionally upregulated by IFN treatment, as well as in animals bearing Gbp1b alleles, in which mGBP1 is not induced in response to IFN treatment. The genomic organizations of the genes encoding mGBP1 and mGBP2 are similar, and the nucleotide sequences of their IFN-responsive-like elements and their relative locations are conserved. Gbp1 and Gbp2 map to a genetically indistinguishable site on the distal arm of chromosome 3.

Daily parenteral administration of exogenous interferon-gamma (IFN-gamma) induces or accelerates recovery in experimental and human infections. To develop an alternative delivery system, a replication-defective recombinant adenovirus expressing human IFN-gamma was constructed. The complete coding region of IFN-gamma was amplified by RT-PCR and inserted into an adenovirus cloning vector under the control of a human cytomegalovirus promoter. Recombinant adenovirus containing the IFN-gamma minigene (dAv-IFN-gamma) was isolated from 293 cells co-transfected with the linearized plasmid and an E1 region-deleted fragment of adenovirus genome. Following in vitro infection with dAv-IFN-gamma, dose-dependent and time-dependent expression of IFN-gamma, mRNA and production of soluble protein were demonstrated in human diploid fibroblat and HeLa cell cultures by Northern blot and ELISA, respectively. Extracellular protein secretion persisted for > = 4 weeks following initial transfection, and secreted IFN-gamma induced both antiviral activity (8000-25,000 U/ml) and macrophage activation with killing of intracellular Toxoplasma gondii and leishmania donovani. These results establish that dAv-IFN-gamma generates long-term secretion of biologically active IFN-gamma in vitro and suggest that this vector may be a useful delivery system for cytokine therapy.

The interferon-mediated induction of the gene encoding the human tryptophanyl tRNA synthetase (WRS) results in the production of two mRNA species differing in size by approximately 800 base pairs (bp). Two distinctly sized cDNAs differing by approximately 800 bp were isolated from a cDNA library generated from mRNA prepared from IFN-γ-treated cells. Northern blot analysis using cDNA probes recognizing different regions of the WRS mRNA reveals distinctly sized mRNAs differing in the length of their 3′ untranslated regions. Differential display analysis using oligo dT primers demonstrates that the different sized WRS mRNAs result from alternative polyadenylation of this transcript.

Glycogen storage disease type Ia (GSDIa) is a severe autosomal recessive disorder caused by deficiency of the enzyme D-glucose-6-phosphatase (G6Pase). While numerous mutations have been found in cosmopolitan European populations, Ashkenazi Jewish (AJ) patients appear to primarily carry the R83C mutation, but possibly also the Q347X mutation found generally in Caucasians. To determine the frequency for both these mutations in the AJ population, we tested 20,719 AJ subjects for the R83C mutation and 4,290 subjects for the Q347X mutation. We also evaluated the mutation status of 30 AJ GSDIa affected subjects. From the carrier screening, we found 290 subjects with R83C, for a carrier frequency for this mutation of 1.4%. This carrier frequency translates into a predicted disease prevalence of 1 in 20,000, five times higher than for the general Caucasian population, confirming a founder effect and elevated frequency of GSDIa in the AJ population. We observed no carriers of the Q347X mutation. Among the 30 GSDIa affected AJ subjects, all were homozygous for R83C. These results indicate that R83C is the only prevalent mutation for GSDIa in the Ashkenazi population.

The ability to modulate the production of the wild-type transcript in cells bearing the splice-altering familial dysautonomia (FD) causing mutation in the IKBKAP gene prompted a study of the impact of a panel of pharmaceuticals on the splicing of this transcript, which revealed the ability of the cardiac glycoside digoxin to increase the production of the wild-type, exon-20-containing, IKBKAP-encoded transcript and the full-length IκB-kinase-complex-associated protein in FD-derived cells. Characterization of the cis elements and trans factors involved in the digoxin-mediated effect on splicing reveals that this response is dependent on an SRSF3 binding site(s) located in the intron 5′ of the alternatively spliced exon and that digoxin mediates its effect by suppressing the level of the SRSF3 protein. Characterization of the digoxin-mediated effect on the RNA splicing process was facilitated by the identification of several RNA splicing events in which digoxin treatment mediates the enhanced inclusion of exonic sequence. Moreover, we demonstrate the ability of digoxin to impact the splicing process in neuronal cells, a cell type profoundly impacted by FD. This study represents the first demonstration that digoxin possesses splice-altering capabilities that are capable of reversing the impact of the FD-causing mutation. These findings support the clinical evaluation of the impact of digoxin on the FD patient population.

We have studied the effect of relatively high concentrations of extracellular N -acetylaspartate (NAA) on the intracellular free calcium concentration [Ca 2+ ] i in NTera2-neurons. While low concentrations of extracellular NAA (0.1, 1 mM) had no effect on the [Ca 2+ ] i , high concentrations of extracellular NAA (3, 10 mM) eliceted sharp and statistically significant elevations of [Ca 2+ ] i . Different classes of antagonists of the N -methyl- d -aspartate (NMDA) receptor abolished the NAA induced elevations of the [Ca 2+ ] i , indicating the involvement of the NMDA receptor in NAA-induced elevations of [Ca 2+ ] i .

N-acetylaspartate (NAA) is the one of the most prominent resonances observed in the solvent-suppressed NMR spectrum of the human brain. Although it is present in the brain at about 10 mM, its precise metabolic function is still unclear, We have examined the NAA as a potential chelator for divalent metal ions such as Ca2+. We have employed the perturbations induced by Ln3+ ions in the 1H and 13C NMR spectrum of NAA to monitor formation of NAA complexes. 1H NMR measurements showed that the dissociation constants for the formation of Eu(3+)-NAA, Yb(3+)-NAA, and Ca(2+)-NAA complexes were 0.07, 0.13, and 0.86 mM, respectively. Scatchard analysis of the results indicates the formation of a 1:1 metal-ligand complex. We also inferred the structure of the NAA-metal ion complex from an analysis of paramagnetic perturbations induced in the 1H NMR and 13C NMR spectra of NAA. The structural analysis of the NAA-metal ion complex indicates that the two carboxylic groups participate in chelating the metal ion, forming the binding site for the metal ion.

Das Leben auf der Erde beruht auf Verbindungen mit einem Kohlenstoffgerust. Bis zum heutigen Tage haben Chemiker die Welt der Biomolekule und Biopolymere um etwa 107 verschiedene synthetische Molekule und Polymere erweitert, deren Struktur ebenfalls von der Bildung stabiler CC-Bindungen abhangt. Obwohl die Stabilitat von CC-Bindungen seit uber hundert Jahren wohlbekannt ist, waren Graphit und Diamant bis vor kurzem die einzigen auf der Erde in makroskopischen Mengen verfugbaren und strukturell charakterisierten Kohlenstoffallotrope. Mit der Darstellung makroskopischer Mengen an Buckminsterfulleren C60 und an hoheren Fullerenen wie C70, C76, und C78 sowie der Erforschung der faszinierenden Eigenschaften dieser Kohlenstoffkugeln hat sich diese Situation inzwischen drastisch geandert. Im Laufe der kommenden Jahrzehnte wird der Entwurf, die Darstellung und das Studium neuer molekularer und polymerer allotroper Formen des Kohlenstoffs eine zentrale Stellung in der Chemie einnehmen. Dies wird zu einer wesentlichen Vertiefung unserer grundlegenden Kenntnisse uber die aus Kohlenstoff aufgebaute Materie fuhren und — wie die aktuelle C60-Forschung zeigt — vollig neue Perspektiven fur technologische Entwicklungen bieten. Dieser Artikel gibt eine ubersicht uber organisch-chemische Synthesestrategien fur ausschlieslich aus Kohlenstoff aufgebaute Molekule und Polymere, welche strukturell von den bekannten Graphit- und Diamant-Netzwerken und auch von den Fullerenen abweichen. Wir diskutieren auch die aktuelle Fullerenforschung, wobei wir besonderes Gewicht auf die Synthesestrategien legen wollen, welche zu den Fullerenen sowie deren ubergangsmetallkomplexen fuhren.

A cDNA clone complementary to an interferon (IFN)-induced mRNA was isolated and used to characterize the regulation of expression of its RNA by the IFNs and to identify the protein its RNA encodes. This cDNA hybridizes to IFN-induced 3.1- and 2.3-kilobase mRNAs that are synthesized in response to both IFN-alpha and IFN-gamma. IFN-gamma induces the sustained accumulation of these mRNAs while IFN-alpha induces their transient accumulation. Cycloheximide (50 micrograms/ml) failed to inhibit the induction of these mRNAs by either IFN-alpha or IFN-gamma, suggesting that their induction does not require de novo protein synthesis. DNA sequence analysis of this cDNA reveals that it encodes a protein of Mr 53,168 that has sequence homology with and the biological activity of a tryptophanyl-tRNA synthetase, an enzymatic activity that has been demonstrated to play a role in and be modulated by the growth of cells. Elevated levels of this enzyme may be involved in the cell growth inhibitory activity of the IFNs.

Leigh syndrome is a neurodegenerative disorder of infancy or childhood generally due to mutations in nuclear or mitochondrial genes involved in mitochondrial energy metabolism. We performed linkage analysis in an Ashkenazi Jewish (AJ) family without consanguinity with three affected children. Linkage to microsatellite markers D5S1969 and D5S407 led to evaluation of the complex I gene NDUFS4, in which we identified a novel homozygous c.462delA mutation that disrupts the reading frame. The resulting protein lacks a cAMP-dependent protein kinase phosphorylation site required for activation of mitochondrial respiratory chain complex I. In a random sample of 5000 healthy AJ individuals, the carrier frequency of the NDUFS4 mutation c.462delA was 1 in 1000, suggesting that it should be considered in all AJ patients with Leigh syndrome.

A partial cDNA clone for the interferon (IFN)-induced 67,000-dalton (67K) protein was isolated by immunological screening and used as a probe to study the expression of mRNAs encoding this protein. Northern blot analyses of RNA from IFN-treated GM2767 cells revealed the presence of two major 67K-specific RNA species, 2.7 and 4.3 kb in length, and two minor RNA species, 5.7 and 7.2 kb long. All of these 67K-specific RNAs were polyadenylated. Multiple 67K-specific mRNAs were observed to be induced in several cell lines. IFN-gamma was more effective at inducing these mRNAs than was IFN-alpha. In IFN-alpha-treated GM2767 cells, the 67K-specific mRNAs were detectable 6 h following IFN treatment, but not 12, 18, or 24 h following treatment. In IFN-gamma-treated cells, these mRNAs were detectable 6 h after treatment and continued to be present 24 h after treatment. The induction of the 67K-specific mRNAs in GM2767 cells did not require protein synthesis as the RNAs were induced by IFN-alpha or IFN-gamma in the presence of cycloheximide (CHX, 50 micrograms/ml). Treatment of cells with the combination of CHX and IFN-alpha mediated an enhanced accumulation of the 67K-specific mRNAs, suggesting that ongoing protein synthesis may downregulate the induction or accumulation of the IFN-alpha-induced 67K-specific mRNAs. Western blot analysis employing a monoclonal antibody to the 67K protein revealed that several distinctly sized but immunologically related proteins were induced in IFN-treated cells.

Familial dysautonomia (FD) is a sensory and autonomic neuropathy that affects the development and survival of sensory, sympathetic, and some parasympathetic neurons. It is autosomally inherited and occurs almost exclusively among individuals of Ashkenazi Jewish descent. The pathological and clinical manisfestations of FD have been extensively studied and therapeutic modalities have, until recently, focused primarily on addressing the symptoms experienced by those with this fatal disorder. The primary FD-causing mutation is an intronic nucleotide substitution that alters the splicing of the IKBKAP-derived transcript. Recent efforts have resulted in the development of new therapeutic modalities that facilitate the increased production of the correctly spliced transcript and mitigate the symptoms of those with FD. Furthermore, the recent demonstration of the reduced presence of monoamine oxidase A in cells and tissues of individuals with FD has provided new insight into the cause of hypertensive crises experienced by these patients.

Nemaline myopathy (NM) is a neuromuscular disorder that is clinically diverse and can be attributed to mutations in any of several genes. The Ashkenazi Jewish population, which represents a relatively genetically homogeneous group, has an increased frequency of several genetic disorders and has been the beneficiary of genetic screening programs that have reduced the incidence of these diseases. The identification of individuals with NM in this population has prompted a study of its cause. Our study has revealed that five NM patients from five families bear an identical 2,502-bp deletion that lies in the nebulin gene and that includes exon 55 and parts of introns 54 and 55. The absence of this exon results in the generation of a transcript that encodes 35 fewer amino acids. An analysis of the gene frequency of this mutation in a random sample of 4,090 Ashkenazi Jewish individuals has revealed a carrier frequency of one in 108.