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1.
J Synchrotron Radiat ; 31(Pt 4): 716-722, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38917017

RESUMEN

The New Advanced Telescope for High ENergy Astrophysics (NewAthena) will be the largest space-based X-ray observatory ever built. It will have an effective area above 1.1 m2 at 1 keV, which corresponds to a polished mirror surface of about 300 m2 due to the grazing incidence. As such a mirror area is not achievable with an acceptable mass even with nested shells, silicon pore optics (SPO) technology will be utilized. In the PTB laboratory at BESSY II, two dedicated beamlines are in use for their characterization with monochromatic radiation at 1 keV and a low divergence well below 2 arcsec: the X-ray Pencil Beam Facility (XPBF 1) and the X-ray Parallel Beam Facility (XPBF 2.0), where beam sizes up to 8 mm × 8 mm are available while maintaining low beam divergence. This beamline is used for characterizing mirror stacks and controlling the focusing properties of mirror modules (MMs) - consisting of four mirror stacks - during their assembly at the beamline. A movable CCD based camera system 12 m from the MM registers the direct and the reflected beams. The positioning of the detector is verified by a laser tracker. The energy-dependent reflectance in double reflection through the pores of an MM with an Ir coating was measured at the PTB four-crystal monochromator beamline in the photon energy range 1.75 keV to 10 keV, revealing the effects of the Ir M edges. The measured reflectance properties are in agreement with the design values to achieve the envisaged effective area.

2.
Neurogastroenterol Motil ; 35(5): e14548, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36942766

RESUMEN

BACKGROUND: Gulf War Illness (GWI) is a chronic, multi-symptom disorder affecting 25%-32% of Gulf War veterans. Veterans with GWI disproportionately suffer from gastrointestinal (GI) disorders. Given the increasing evidence supporting a gut-brain axis, we explore the relationship between post-traumatic stress disorder (PTSD), GWI, and self-reported GI disorders among GW veterans. METHODS: Veterans from the Gulf War Era Cohort and Biorepository responded to a mail-based survey (N = 1058). They were stratified by GWI (Centers for Disease Control definition) and PTSD status. This yielded three groups: GWI-, GWI+/PTSD-, and GWI+/PTSD+. Multivariable logistic regression adjusting for demographic and military characteristics examined associations between GWI/PTSD groups and GI disorders. Results were expressed as adjusted odds ratios (aOR) with 95% confidence intervals (95% CI). KEY RESULTS: The most frequently reported GI disorders were irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD), and colon polyps (CP). The GWI+/PTSD+ group had a higher odds of these disorders than the GWI+/PTSD- group (aORIBS  = 3.12, 95% CI: 1.93-5.05; aORGERD  = 2.04, 95% CI: 1.44-2.90; aORCP  = 1.85, 95% CI: 1.23-2.80), which had a higher odds of these disorders than the GWI- group (aORIBS  = 4.38, 95% CI: 1.55-12.36; aORGERD  = 2.51 95% CI: 1.63-3.87; aORCP  = 2.57, 95% CI: 1.53-4.32). CONCLUSIONS & INFERENCES: GW veterans with GWI and PTSD have significantly higher odds of specific self-reported GI disorders than the other groups. Given the known bidirectional influences of the gut and brain, these veterans may benefit from a holistic healthcare approach that considers biopsychosocial contributors to the assessment and management of disease.


Asunto(s)
Reflujo Gastroesofágico , Enfermedades Gastrointestinales , Síndrome del Colon Irritable , Síndrome del Golfo Pérsico , Trastornos por Estrés Postraumático , Veteranos , Humanos , Veteranos/psicología , Autoinforme , Guerra del Golfo
3.
Infect Immun ; 83(6): 2338-49, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25824835

RESUMEN

In this study, the cytotoxicity of the recently described subtilase variant SubAB2-2 of Shiga toxin-producing Escherichia coli was determined and compared to the plasmid-encoded SubAB1 and the chromosome-encoded SubAB2-1 variant. The genes for the respective enzymatic active (A) subunits and binding (B) subunits of the subtilase toxins were amplified and cloned. The recombinant toxin subunits were expressed and purified. Their cytotoxicity on Vero cells was measured for the single A and B subunits, as well as for mixtures of both, to analyze whether hybrids with toxic activity can be identified. The results demonstrated that all three SubAB variants are toxic for Vero cells. However, the values for the 50% cytotoxic dose (CD50) differ for the individual variants. Highest cytotoxicity was shown for SubAB1. Moreover, hybrids of subunits from different subtilase toxins can be obtained which cause substantial cytotoxicity to Vero cells after mixing the A and B subunits prior to application to the cells, which is characteristic for binary toxins. Furthermore, higher concentrations of the enzymatic subunit SubA1 exhibited cytotoxic effects in the absence of the respective B1 subunit. A more detailed investigation in the human HeLa cell line revealed that SubA1 alone induced apoptosis, while the B1 subunit alone did not induce cell death.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Proteínas Recombinantes/metabolismo , Escherichia coli Shiga-Toxigénica/enzimología , Subtilisinas/metabolismo , Animales , Apoptosis/efectos de los fármacos , Chlorocebus aethiops , Clonación Molecular , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Variación Genética , Células HeLa , Humanos , Subunidades de Proteína , Proteínas Recombinantes/genética , Escherichia coli Shiga-Toxigénica/genética , Subtilisinas/genética , Células Vero
4.
J Appl Microbiol ; 119(1): 1-10, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25809882

RESUMEN

Deinococcus spp are among the most radiation-resistant micro-organisms that have been discovered. They show remarkable resistance to a range of damage caused by ionizing radiation, desiccation, UV radiation and oxidizing agents. Traditionally, Escherichia coli and Saccharomyces cerevisiae have been the two platforms of choice for engineering micro-organisms for biotechnological applications, because they are well understood and easy to work with. However, in recent years, researchers have begun using Deinococcus spp in biotechnologies and bioremediation due to their specific ability to grow and express novel engineered functions. More recently, the sequencing of several Deinococcus spp and comparative genomic analysis have provided new insight into the potential of this genus. Features such as the accumulation of genes encoding cell cleaning systems that eliminate organic and inorganic cell toxic components are widespread among Deinococcus spp. Other features such as the ability to degrade and metabolize sugars and polymeric sugars make Deinococcus spp. an attractive alternative for use in industrial biotechnology.


Asunto(s)
Deinococcus/genética , Microbiología Industrial , Biopelículas , Biotecnología , Pared Celular/química , Deinococcus/citología , Deinococcus/fisiología , Microbiología Industrial/instrumentación , Microbiología Industrial/métodos , Estrés Oxidativo
5.
J Appl Microbiol ; 110(1): 248-53, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20961365

RESUMEN

AIMS: To analyse genetic changes in the oafA gene explaining the loss of O5-antigen expression in Salmonella Typhimurium and Salm. 4,[5],12:i:-. METHODS AND RESULTS: The oafA gene in 52 O5-antigen-negative and 77 O5-antigen-positive Salm. Typhimurium (N = 47) and Salm. 4,[5],12:i:- (monophasic Salm. Typhimurium strains, N = 82) was investigated by a combination of PCR screening and DNA sequencing to identify mutations leading to the suppression of the O5-antigen. Various DNA sequence changes within the open reading frame (ORF) of oafA in O5-antigen-negative strains could be identified. In 77% of the O5-antigen-negative strains, a 7-bp deletion of a duplicated sequence within the functional oafA gene led to a frameshift in the ORF. In four strains, an IS4 element and in two, an IS1 element was inserted at different positions. Four other strains carried at different positions single base pair substitutions causing a premature stop codon. Finally, in two strains, a deletion of the oafA 3'end of undetermined size was responsible for the lack of O5-antigen expression. In none of the strains investigated, the complete ORF of oafA was deleted. Primers were designed and used to detect the most prominent variants. CONCLUSIONS: O5-antigen-negative Salm. Typhimurium and Salm. 4,[5],12:i:- strains carry an oafA pseudogene caused by different genetic events indicating that there is a selection for oafA mutations leading to the loss of O5-antigen expression. SIGNIFICANCE AND IMPACT OF THE STUDY: The loss of O5-antigen expression may be an example of a common evolutionary mechanism to escape host defence or to adapt to environmental changes. The data are the basis for the development of diagnostic PCR assays for the differentiation of O5-antigen-positive and O5-antigen-negative Salm. Typhimurium and its monophasic (Salm. 4,[5],12:i-) strains.


Asunto(s)
Acetiltransferasas/genética , Proteínas Bacterianas/genética , Antígenos O/metabolismo , Salmonella typhimurium/genética , Genes Bacterianos , Mutación , Antígenos O/genética , Reacción en Cadena de la Polimerasa , Salmonella typhimurium/clasificación , Salmonella typhimurium/inmunología
6.
Ann Hum Genet ; 72(Pt 4): 443-53, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18318786

RESUMEN

Previous association mapping on chromosome 3q13-21 detected evidence for association at the limbic system-associated membrane protein (LSAMP) gene in individuals with late-onset coronary artery disease (CAD). LSAMP has never been implicated in the pathogenesis of CAD. We sought to thoroughly characterize the association and the gene. Non-redundant single nucleotide polymorphisms (SNPs) across the gene were examined in an initial dataset (168 cases with late-onset CAD, 149 controls). Stratification analysis on left main CAD (N = 102) revealed stronger association, which was further validated in a validation dataset (141 cases with left main CAD, 215 controls), a third control dataset (N = 255), and a family-based dataset (N = 2954). A haplotype residing in a novel alternative transcript of the LSAMP gene was significant in all independent case-control datasets (p = 0.0001 to 0.0205) and highly significant in the joint analysis (p = 0.00004). Lower expression of the novel alternative transcript was associated with the risk haplotype (p = 0.0002) and atherosclerosis burden in human aortas (p = 0.0001). Furthermore, silencing LSAMP expression in human aortic smooth muscle cells (SMCs) substantially augmented SMC proliferation (p<0.01). Therefore, the risk conferred by the LSAMP haplotype appears to be mediated by LSAMP down-regulation, which may promote SMC proliferation in the arterial wall and progression of atherosclerosis.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/genética , Enfermedad de la Arteria Coronaria/genética , Polimorfismo de Nucleótido Simple , Proteínas Supresoras de Tumor/genética , Edad de Inicio , Anciano , Aorta/metabolismo , Aterosclerosis/genética , Aterosclerosis/metabolismo , Estudios de Casos y Controles , Moléculas de Adhesión Celular Neuronal/metabolismo , Células Cultivadas , Cromosomas Humanos Par 3/genética , Enfermedad de la Arteria Coronaria/metabolismo , Regulación hacia Abajo , Femenino , Proteínas Ligadas a GPI , Expresión Génica , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Regiones Promotoras Genéticas , Factores de Riesgo , Proteínas Supresoras de Tumor/metabolismo
7.
Ann Hum Genet ; 70(Pt 6): 738-48, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17044848

RESUMEN

Coronary artery disease (CAD) and dyslipidemia have strong genetic components. Heterogeneity complicates evaluating genetics of complex diseases such as CAD; incorporating disease-related phenotypes may help reduce heterogeneity. We hypothesized that incorporating lipoproteins in a study of CAD would increase the power to map genes, narrow linkage peaks, identify phenotypic subsets, and elucidate the contribution of established risk factors to genetic results. We performed ordered subset analysis (OSA) and quantitative trait linkage (QTL) using serum lipoproteins and microsatellite markers in 346 families with early-onset CAD. OSA defined homogeneous subsets and calculated lod scores across a chromosome after ranking families by mean lipoprotein values. QTL used variance components analysis. We found significantly increased linkage to chromosome 3q13 (LOD 5.10, p = 0.008) in families with higher HDL cholesterol, lower LDL and total cholesterol, lower triglycerides, and fewer CAD risk factors, possibly due to a concentrated non-lipoprotein-related genetic effect. OSA identified linkage on chromosome 5q34 in families with higher cholesterol, possibly representing a hereditary lipoprotein phenotype. Multiple QTLs were identified, with the strongest for: total cholesterol on chromosome 5q14 (LOD 4.3); LDL on 20p12 (LOD 3.97); HDL on 3p14 (LOD 1.65); triglycerides on 18q22 (LOD 1.43); and HDL/TC ratio on 3q27-28 (LOD 2.06). Our findings suggest the presence of etiologic heterogeneity in families with early-onset CAD, potentially due to differential effects of lipoprotein phenotypes. Candidate genes are under investigation.


Asunto(s)
Cromosomas Humanos Par 3 , Cromosomas Humanos Par 5 , Enfermedad de la Arteria Coronaria/genética , Lipoproteínas/sangre , Sitios de Carácter Cuantitativo , Adulto , Enfermedad de la Arteria Coronaria/diagnóstico , Femenino , Ligamiento Genético , Variación Genética , Humanos , Lipoproteínas/genética , Escala de Lod , Masculino , Persona de Mediana Edad , Fenotipo
8.
J Med Genet ; 42(12): e68, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16326825

RESUMEN

Multipoint linkage analysis in complex diseases requires the use of fast algorithms that can handle many markers and a large number of moderately sized pedigrees with unknown mode of inheritance. This need has led to the development of several competitive software programs. We recently completed a genomic screen of neural tube defects using GENEHUNTER-PLUS and the more recent ALLEGRO. The ALLEGRO software was found to offer expanded power for linkage studies, particularly for childhood onset diseases like neural tube defects, though the results must be treated with caution.


Asunto(s)
Biología Computacional/métodos , Ligamiento Genético , Algoritmos , Femenino , Genotipo , Humanos , Desequilibrio de Ligamiento , Escala de Lod , Masculino , Defectos del Tubo Neural/genética , Linaje , Programas Informáticos
9.
Neuropediatrics ; 36(3): 210-3, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15944908

RESUMEN

Severe myoclonic epilepsy in infancy (SMEI), severe idiopathic generalized epilepsy of infancy (SIGEI) with generalized tonic clonic seizures (GTCS), and myoclonic astatic epilepsy (MAE) may show semiological overlaps. In GEFS+ families, all three phenotypes were found associated with mutations in the SCN1A gene. We analyzed the SCN1A gene in 20 patients with non-familial myoclonic astatic epilepsy -- including 12 probands of the original cohort used by Doose et al. in 1970 to delineate MAE. In addition, 18 patients with sporadic SIGEI -- mostly without myoclonic-astatic seizures -- were analyzed. Novel SCN1A mutations were found in 3 individuals. A frame shift resulting in an early premature stop codon in a now 35-year-old woman with a borderline phenotype of MAE and SIGEI (L433fsX449) was identified. A splice site variant (IVS18 + 5 G --> C) and a missense mutation in the conserved pore region (40736 C --> A; R946 S) were detected each in a child with SIGEI. We conclude that, independent of precise syndromic delineation, myoclonic-astatic seizures are not predictive of SCN1A mutations in sporadic myoclonic epilepsies of infancy and early childhood.


Asunto(s)
Epilepsias Mioclónicas/genética , Epilepsia Tónico-Clónica/genética , Proteínas del Tejido Nervioso/genética , Canales de Sodio/genética , Niño , Desarrollo Infantil , Análisis Mutacional de ADN , Epilepsias Mioclónicas/fisiopatología , Epilepsias Mioclónicas/psicología , Epilepsia Tónico-Clónica/fisiopatología , Epilepsia Tónico-Clónica/psicología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Canal de Sodio Activado por Voltaje NAV1.1
10.
Pac Symp Biocomput ; : 93-103, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14992495

RESUMEN

We have developed a software package, SIMLA (simulation of linkage and association), which can be used to generate pedigree data under user-specified conditions. The number and location of disease loci, disease penetrances, marker locations, and marker disequilibrium with a disease locus and with other markers can be controlled. In addition, the pedigree size and availability of genotype data may also be specified, and a number of rules for family ascertainment are available. Estimates for power and type I errors can be evaluated under a variety of conditions, as needed by the user. We developed this simulation program because there are no publicly available programs to simulate variable levels of both recombination and linkage disequilibrium (LD) in general pedigrees. Genetic researchers are routinely applying both tests of linkage and family-based tests of association in the search for complex disease genes, and a plethora of different statistical approaches are available. Thus there is a need for the flexible statistical simulation program that we describe. This is the only program that we are aware of that allows simulation of linkage and association for multiple markers in extended pedigrees, nuclear families or in sets of unrelated cases and controls. Furthermore, the program not only allows for variable levels of LD among markers but also between markers and disease loci. SIMLA can simulate the complex and variable levels of LD that have been observed at close markers across the genome and allows for realistic simulation of complex relationships between markers. The program will be useful for studying and comparing existing statistical tests, for developing new genetic linkage and association statistics, planning sample sizes for new studies, and interpreting genetic analysis results.


Asunto(s)
Biología Computacional , Ligamiento Genético , Linaje , Algoritmos , Alelos , Femenino , Marcadores Genéticos , Humanos , Desequilibrio de Ligamiento , Masculino , Programas Informáticos
11.
Genet Epidemiol ; 25(3): 203-13, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14557988

RESUMEN

Many family-based tests of linkage disequilibrium (LD) are based on counts of alleles rather than genotypes. However, allele-based tests may not detect interactions among alleles at a single locus that are apparent when examining associations with genotypes. Family-based tests of LD based on genotypes have been developed, but they are typically valid as tests of association only in families with a single affected individual. To take advantage of families with multiple affected individuals, we propose the genotype-pedigree disequilibrium test (geno-PDT) to test for LD between marker locus genotypes and disease. Unlike previous tests for genotypic association, the geno-PDT is valid in general pedigrees. Simulations to compare the power of the allele-based PDT and geno-PDT reveal that under an additive model, the allele-based PDT is more powerful, but that the geno-PDT can have greater power when the genetic model is recessive or dominant. Perhaps the most important property of the geno-PDT is the ability to test for association with particular genotypes, which can reveal underlying patterns of association at the genotypic level. These genotype-specific tests can be used to suggest possible underlying genetic models that are consistent with the pattern of genotypic association. This is illustrated through an application to a candidate gene analysis of the MLLT3 gene in families with Alzheimer disease. The geno-PDT approach for testing genotypes in general family data provides a useful tool for identifying genes in complex disease, and partitioning individual genotype contributions will help to dissect the influence of genotype on risk.


Asunto(s)
Genotipo , Linaje , Estadística como Asunto , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/genética , Simulación por Computador , Interpretación Estadística de Datos , Humanos , Desequilibrio de Ligamiento , Modelos Genéticos , Modelos Estadísticos
12.
Am J Hum Genet ; 72(3): 539-48, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12567325

RESUMEN

Autistic disorder (AutD) is a complex genetic disease. Available evidence suggests that several genes contribute to the underlying genetic risk for the development of AutD. However, both etiologic heterogeneity and genetic heterogeneity confound the discovery of AutD-susceptibility genes. Chromosome 15q11-q13 has been identified as a strong candidate region on the basis of both the frequent occurrence of chromosomal abnormalities in that region and numerous suggestive linkage and association findings. Ordered-subset analysis (OSA) is a novel statistical method to identify a homogeneous subset of families that contribute to overall linkage at a given chromosomal location and thus to potentially help in the fine mapping and localization of the susceptibility gene within a chromosomal area. For the present analysis, a factor that represents insistence on sameness (IS)--derived from a principal-component factor analysis using data on 221 patients with AutD from the repetitive behaviors/stereotyped patterns domain in the Autism Diagnostic Interview-Revised--was used as a covariate in OSA. Analysis of families sharing high scores on the IS factor increased linkage evidence for the 15q11-q13 region, at the GABRB3 locus, from a LOD score of 1.45 to a LOD score of 4.71. These results narrow our region of interest on chromosome 15 to an area surrounding the gamma-aminobutyric acid-receptor subunit genes, in AutD, and support the hypothesis that the analysis of phenotypic homogeneous subtypes may be a powerful tool for the mapping of disease-susceptibility genes in complex traits.


Asunto(s)
Trastorno Autístico/genética , Cromosomas Humanos Par 15 , Trastorno Autístico/clasificación , Biometría , Aberraciones Cromosómicas , Mapeo Cromosómico , ADN/sangre , ADN/genética , Familia , Genes Dominantes , Genes Recesivos , Ligamiento Genético , Marcadores Genéticos , Humanos , Escala de Lod , Análisis Multivariante , Fenotipo
13.
J Neural Transm Suppl ; (67): 173-91, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15068250

RESUMEN

In comparison to most other groups with intellectual disability individuals with Down syndrome are at lower risk for significant psychopathology, although relative to their typically developing peers they have higher rates of behavioural and emotional problems. A total of 43 Down syndrome patients (21 females and 22 males), who ranged in age from 5.33 to 30.58 years, were examined for the presence of age-related changes in the spectrum of externalizing and internalizing problems. Intelligence tests included Hamburg-Wechsler-Intelligenz Test für Kinder III (HAWIK-III), Hamburg-Wechsler-Intelligenz Test für Erwachsene (HAWIE-R) and Kaufman-Assessment-Battery for Children, German Version (K-ABC). Behavioural and emotional problems were assessed by the the Strengths and Difficulties Questionnaire for Parents, German Version (SDQ) and the Clinical Assessment Scale for Child and Adolescent Psychopathology (CASCAP). IQ was significantly inversly related to the age of patients. Externalizing behaviours (dominant, opposing/refusing, impulsiveness, inattention and increased motor activity) were significantly higher in the 5-10 years old group, whereas internalizing behaviours (shy/insecure, low self confidence, decreased motor activity) where more prevalent in adolescents and adults (10-30 years). Possible relationships between this age-related changes and increased risks of later-onset psychopathology (depression and dementia) are discussed.


Asunto(s)
Síntomas Afectivos/psicología , Trastornos del Conocimiento/psicología , Síndrome de Down/psicología , Trastorno de la Conducta Social/psicología , Adolescente , Adulto , Síntomas Afectivos/complicaciones , Factores de Edad , Distribución de Chi-Cuadrado , Niño , Preescolar , Trastornos del Conocimiento/complicaciones , Estudios de Cohortes , Estudios Transversales , Síndrome de Down/complicaciones , Femenino , Humanos , Pruebas de Inteligencia/estadística & datos numéricos , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricos , Trastorno de la Conducta Social/complicaciones
14.
J Org Chem ; 67(22): 7750-60, 2002 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-12398499

RESUMEN

Rhizoxin D (2) was synthesized from four subunits, A, B, C, and D representing C3-C9, C10-C13, C14-C19, and C20-C27, respectively. Subunit A was prepared by cyclization of iodo acetal 21, which set the configuration at C5 of 2 through a stereoselective addition of the radical derived from dehalogenation of 21 at the beta carbon of the (Z)-alpha,beta-unsaturated ester. Aldehyde 29 was obtained from phenylthioacetal 24 and condensed with phosphorane 30, representing subunit B, in a Wittig reaction that gave the (E,E)-dienoate 31. This ester was converted to aldehyde 33 in preparation for coupling with subunit C. The latter in the form of methyl ketone 55 was obtained in six steps from propargyl alcohol. An aldol reaction of 33 with the enolate of 55 prepared with (+)-DIPCl gave the desired beta-hydroxy ketone 56 bearing a (13S)-configuration in a 17-20:1 ratio with its (13R)-diastereomer. After reduction to anti diol 57 and selective protection as TIPS ether 58, the C15 hydroxyl was esterified to give phosphonate 59. An intramolecular Wadsworth-Emmons reaction of aldehyde 62, derived from delta-lactone 60, furnished macrolactone 63, which was coupled in a Stille reaction with stannane 68 to give 2 after cleavage of the TIPS ether.


Asunto(s)
Antineoplásicos/síntesis química , Lactonas/síntesis química , Rhizopus/química , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Lactonas/química , Lactonas/aislamiento & purificación , Lactonas/farmacología , Estructura Molecular
15.
Hum Mol Genet ; 10(25): 2879-87, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11741831

RESUMEN

The skeletal muscle ryanodine receptor gene (RYR1; OMIM 180901) on chromosome 19q13.1 encodes the skeletal muscle calcium release channel. To date, more than 25 missense mutations have been identified in RYR1 and are associated with central core disease (CCD; OMIM 117000) and/or the malignant hyperthermia susceptibility phenotype (MHS1; OMIM 145600). The majority of RYR1 mutations are clustered in the N-terminal hydrophilic domain of the protein. Only four mutations have been identified so far in the highly conserved C-terminal region encoding the luminal/transmembrane domain of the protein which forms the ion pore. Three of these mutations have been found to segregate with pure or mixed forms of CCD. We have screened the C-terminal domain of the RYR1 gene for mutations in 50 European patients, diagnosed clinically and/or histologically as having CCD. We have identified five missense mutations (four of them novel) in 13 index patients. The mutations cluster in exons 101 and 102 and replace amino acids which are conserved in all known vertebrate RYR genes. In order to study the functional effect of these mutations, we have immortalized B-lymphocytes from some of the patients and studied their [Ca(2+)](i) homeostasis. We show that lymphoblasts carrying the newly identified RYR1 mutations exhibit: (i) a release of calcium from intracellular stores in the absence of any pharmacological activators of RYR; (ii) significantly smaller thapsigargin-sensitive intracellular calcium stores, compared to lymphoblasts from control individuals; and (iii) a normal sensitivity of the calcium release to the RYR inhibitor dantrolene. Our data suggest the C-terminal domain of RYR1 as a hot spot for mutations leading to the CCD phenotype. If the functional alterations of mutated RYR channels observed in lymphoblastoid cells are also present in skeletal muscles this could explain the predominant symptom of CCD, i.e. chronic muscle weakness. Finally, the study of calcium homeostasis in lymphoblastoid cells naturally expressing RYR1 mutations offers a novel non-invasive approach to gain insights into the pathogenesis of MH and CCD.


Asunto(s)
Calcio/metabolismo , Membrana Celular/química , Músculo Esquelético/metabolismo , Mutación/genética , Miopatía del Núcleo Central/genética , Canal Liberador de Calcio Receptor de Rianodina/genética , Secuencia de Aminoácidos , Estudios de Cohortes , ADN/química , ADN/genética , Análisis Mutacional de ADN , Cartilla de ADN/química , Exones , Humanos , Datos de Secuencia Molecular , Miopatía del Núcleo Central/patología , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Aminoácido
16.
Curr Protoc Hum Genet ; Chapter 1: Unit 1.2, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18428235

RESUMEN

This unit covers the important criteria and methods for appropriately selecting pedigrees for linkage analysis. It includes methods for determining the power of a dataset to detect genetic loci for both model-based (lod score) and model-free (affected sib-pair, affected-relative pair) analyses. This unit covers the important criteria and methods for appropriately selecting pedigrees for linkage analysis.


Asunto(s)
Técnicas Genéticas , Linaje , Biología Computacional , Femenino , Ligamiento Genético , Genética Médica , Humanos , Escala de Lod , Masculino
17.
Genet Epidemiol ; 21 Suppl 1: S546-51, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11793734

RESUMEN

A multiple analytic approach may be useful for analyzing complex traits since different methods extract both similar and distinct, but complementary pieces of information from genome screen data on extended pedigrees. We examined the usefulness of combining p-values both across methods and across adjacent markers, taking into account the observed correlation structure among these p-values. To this end, we employed the recently proposed truncated product method [Zaykin et al., Genet Epidemiol, in press]. It appears that this approach is helpful for visualizing priority regions for follow-up analysis and reducing the number of false-positive linkage signals.


Asunto(s)
Mapeo Cromosómico/estadística & datos numéricos , Predisposición Genética a la Enfermedad/genética , Pruebas Genéticas , Modelos Genéticos , Genotipo , Humanos , Cómputos Matemáticos , Fenotipo , Programas Informáticos
18.
Am J Hum Genet ; 67(5): 1174-85, 2000 11.
Artículo en Inglés | MEDLINE | ID: mdl-11032783

RESUMEN

We performed a genome scan at an average resolution of 8 cM in 719 Finnish sib pairs with type 2 diabetes. Our strongest results are for chromosome 20, where we observe a weighted maximum LOD score (MLS) of 2.15 at map position 69.5 cM from pter and secondary weighted LOD-score peaks of 2.04 at 56.5 cM and 1.99 at 17.5 cM. Our next largest MLS is for chromosome 11 (MLS = 1.75 at 84.0 cM), followed by chromosomes 2 (MLS = 0.87 at 5.5 cM), 10 (MLS = 0.77 at 75.0 cM), and 6 (MLS = 0.61 at 112.5 cM), all under an additive model. When we condition on chromosome 2 at 8.5 cM, the MLS for chromosome 20 increases to 5.50 at 69.0 cM (P=.0014). An ordered-subsets analysis based on families with high or low diabetes-related quantitative traits yielded results that support the possible existence of disease-predisposing genes on chromosomes 6 and 10. Genomewide linkage-disequilibrium analysis using microsatellite marker data revealed strong evidence of association for D22S423 (P=.00007). Further analyses are being carried out to confirm and to refine the location of these putative diabetes-predisposing genes.


Asunto(s)
Cromosomas Humanos/genética , Diabetes Mellitus Tipo 2/genética , Predisposición Genética a la Enfermedad/genética , Anciano , Mapeo Cromosómico , Diabetes Mellitus Tipo 2/sangre , Ayuno , Femenino , Finlandia , Genoma Humano , Humanos , Desequilibrio de Ligamiento/genética , Escala de Lod , Masculino , Análisis por Apareamiento , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Núcleo Familiar , Carácter Cuantitativo Heredable , Estados Unidos
19.
Am J Hum Genet ; 67(5): 1186-200, 2000 11.
Artículo en Inglés | MEDLINE | ID: mdl-11032784

RESUMEN

Type 2 diabetes mellitus is a complex disorder encompassing multiple metabolic defects. We report results from an autosomal genome scan for type 2 diabetes-related quantitative traits in 580 Finnish families ascertained for an affected sibling pair and analyzed by the variance components-based quantitative-trait locus (QTL) linkage approach. We analyzed diabetic and nondiabetic subjects separately, because of the possible impact of disease on the traits of interest. In diabetic individuals, our strongest results were observed on chromosomes 3 (fasting C-peptide/glucose: maximum LOD score [MLS] = 3.13 at 53.0 cM) and 13 (body-mass index: MLS = 3.28 at 5.0 cM). In nondiabetic individuals, the strongest results were observed on chromosomes 10 (acute insulin response: MLS = 3.11 at 21.0 cM), 13 (2-h insulin: MLS = 2.86 at 65.5 cM), and 17 (fasting insulin/glucose ratio: MLS = 3.20 at 9.0 cM). In several cases, there was evidence for overlapping signals between diabetic and nondiabetic individuals; therefore we performed joint analyses. In these joint analyses, we observed strong signals for chromosomes 3 (body-mass index: MLS = 3.43 at 59.5 cM), 17 (empirical insulin-resistance index: MLS = 3.61 at 0.0 cM), and 19 (empirical insulin-resistance index: MLS = 2.80 at 74.5 cM). Integrating genome-scan results from the companion article by Ghosh et al., we identify several regions that may harbor susceptibility genes for type 2 diabetes in the Finnish population.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Pruebas Genéticas , Genoma Humano , Carácter Cuantitativo Heredable , Factores de Edad , Glucemia/metabolismo , Índice de Masa Corporal , Cromosomas Humanos/genética , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Ayuno , Femenino , Finlandia , Ligamiento Genético/genética , Predisposición Genética a la Enfermedad/genética , Humanos , Insulina/sangre , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Núcleo Familiar , Factores Sexuales , Estados Unidos
20.
Pediatr Neurol ; 23(3): 271-3, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11033294

RESUMEN

We report a 3-year-old female with anoxic-epileptic seizures. Beginning at 11 months of age, she had repeated breath-holding spells with transition into generalized tonic-clonic seizures or status epilepticus. Interictal electroencephalography exhibited no abnormalities. A multidisciplinary diagnostic approach revealed a severely disturbed mother-daughter relationship that was the trigger of the breath-holding spells. Psychotherapy for the mother and daughter led to cessation of the breath-holding spells and, consequently, of the anoxic-epileptic seizures. Her further development was largely normal. We discuss the etiology and treatment of anoxic-epileptic seizures. This case is the first reported case of anoxic epileptic seizures that responded to psychologic rather than antiepileptic treatment. We advocate an initial psychologic assessment to help determine the appropriate treatment in children with recurrent anoxic-epileptic seizures.


Asunto(s)
Apnea/complicaciones , Epilepsia Generalizada/diagnóstico , Epilepsia Tónico-Clónica/diagnóstico , Hipoxia Encefálica/complicaciones , Apnea/psicología , Preescolar , Diagnóstico Diferencial , Epilepsia Generalizada/psicología , Epilepsia Tónico-Clónica/psicología , Femenino , Estudios de Seguimiento , Humanos , Hipoxia Encefálica/psicología , Lactante , Relaciones Madre-Hijo , Psicoterapia
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