978 resultados para Brothers


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Hymenoptera exhibit an incredible diversity of phenotypes, the result of similar to 240 million years of evolution and the primary subject of more than 250 years of research. Here we describe the history, development, and utility of the Hymenoptera Anatomy Ontology (HAO) and its associated applications. These resources are designed to facilitate accessible and extensible research on hymenopteran phenotypes. Outreach with the hymenopterist community is of utmost importance to the HAO project, and this paper is a direct response to questions that arose from project workshops. In a concerted attempt to surmount barriers of understanding, especially regarding the format, utility, and development of the HAO, we discuss the roles of homology, "preferred terms", and "structural equivalency". We also outline the use of Universal Resource Identifiers (URIs) and posit that they are a key element necessary for increasing the objectivity and repeatability of science that references hymenopteran anatomy. Pragmatically, we detail a mechanism (the "URI table") by which authors can use URIs to link their published text to the HAO, and we describe an associated tool (the "Analyzer") to derive these tables. These tools, and others, are available through the HAO Portal website (http://portal.hymao.org). We conclude by discussing the future of the HAO with respect to digital publication, cross-taxon ontology alignment, the advent of semantic phenotypes, and community-based curation.

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We report a case of adrenal hypoplasia congenita (AHC) and hypogonadotropic hypogonadism (HH) due to a novel DAX1 mutation. A 19-month-old boy with hyperpigmentation and failure to thrive came to our service for investigation. Three brothers of the patient had died due to adrenal failure, and a maternal cousin had adrenal insufficiency. Adrenoleukodystrophy was excluded. MRI showed normal pituitary and hypothalamus. Plasma hormone evaluation revealed high ACTH (up to 2,790 pg/mL), and low levels of androstenedione, DHEA-S, 11-deoxycortisol, and cortisol. At 14 years of age the patient was still prepubescent, his weight was 43.6 kg (SDS: -0.87) and his height was 161 cm (SDS: -0.36), with normal body proportions. In the GnRH test, basal and maximum values of LH and FSH were respectively 0.6/2.1 and < 1.0/< 1.0 U/L. Molecular investigation identified a novel mutation that consists of a deletion of codon 372 (AAC; asparagine) in exon 1 of DAX1. This mutation was not found in a study of 200 alleles from normal individuals. Prediction site analysis indicated that this alteration, located in the DAX1 ligand-binding domain, may damage DAX1 protein. We hypothesize that the novel (p.Asp372del) DAX1 mutation might be able to cause a disruption of DAX1 function, and is probably involved in the development of AHC and HH in this patient. Arq Bras Endocrinol Metab. 2012;56(8):496-500

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Abstract Background Clinical studies for testing new drugs against hepatitis B ought to be carried out in low prevalence areas despite difficulties on patient recruitment. In such areas, relatives of chronic hepatitis B patients are considered to be at risk of acquiring the hepatitis B virus (HBV). The aim of this study was to evaluate the prevalence of HBV markers (anti-HBc, HBsAg and anti-HBs) in familial members of chronic hepatitis B (CHB) patients according to their origin (Asian or Western) in a low prevalence area, the city of São Paulo, Brazil. Methods Twenty three Asian CHB probands and their 313 relatives plus 31 CHB probands of Western origin and their 211 relatives were screened for HBV serological markers; the study was carried out in the outpatient clinic of the University of São Paulo School of Medicine. Results Mother to child transmission was greater in the Asian group whereas sexual transmission was more frequent in the Western group (p < 0.0001). Anti-HBc was positive in 90% and 57% of the Asian and Western parents (p = 0.0432) and in 97% and 33% of the Asian and Western brothers (p = 0.0001), respectively. HBsAg was more frequent among the Asian (66%) than the Western (15%) mothers (p = 0.0260) as well as among the Asian (81%) than the Western (19%) brothers (p = 0.0001). We could detect 110 new HBsAg-positive subjects related to the 54 index patients, being the majority (81%) of Asian origin. Conclusion In low prevalence area of hepatitis B, family members and household contacts of chronic HBV carriers are at high risk for acquiring hepatitis B.

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Self-incompatibility (SI) systems have evolved in many flowering plants to prevent self-fertilization and thus promote outbreeding. Pear and apple, as many of the species belonging to the Rosaceae, exhibit RNase-mediated gametophytic self-incompatibility, a widespread system carried also by the Solanaceae and Plantaginaceae. Pear orchards must for this reason contain at least two different cultivars that pollenize each other; to guarantee an efficient cross-pollination, they should have overlapping flowering periods and must be genetically compatible. This compatibility is determined by the S-locus, containing at least two genes encoding for a female (pistil) and a male (pollen) determinant. The female determinant in the Rosaceae, Solanaceae and Plantaginaceae system is a stylar glycoprotein with ribonuclease activity (S-RNase), that acts as a specific cytotoxin in incompatible pollen tubes degrading cellular RNAs. Since its identification, the S-RNase gene has been intensively studied and the sequences of a large number of alleles are available in online databases. On the contrary, the male determinant has been only recently identified as a pollen-expressed protein containing a F-box motif, called S-Locus F-box (abbreviated SLF or SFB). Since F-box proteins are best known for their participation to the SCF (Skp1 - Cullin - F-box) E3 ubiquitine ligase enzymatic complex, that is involved in protein degradation through the 26S proteasome pathway, the male determinant is supposed to act mediating the ubiquitination of the S-RNases, targeting them for the degradation in compatible pollen tubes. Attempts to clone SLF/SFB genes in the Pyrinae produced no results until very recently; in apple, the use of genomic libraries allowed the detection of two F-box genes linked to each S haplotype, called SFBB (S-locus F-Box Brothers). In Japanese pear, three SFBB genes linked to each haplotype were cloned from pollen cDNA. The SFBB genes exhibit S haplotype-specific sequence divergence and pollen-specific expression; their multiplicity is a feature whose interpretation is unclear: it has been hypothesized that all of them participate in the S-specific interaction with the RNase, but it is also possible that only one of them is involved in this function. Moreover, even if the S locus male and female determinants are the only responsible for the specificity of the pollen-pistil recognition, many other factors are supposed to play a role in GSI; these are not linked to the S locus and act in a S-haplotype independent manner. They can have a function in regulating the expression of S determinants (group 1 factors), modulating their activity (group 2) or acting downstream, in the accomplishment of the reaction of acceptance or rejection of the pollen tube (group 3). This study was aimed to the elucidation of the molecular mechanism of GSI in European pear (Pyrus communis) as well as in the other Pyrinae; it was divided in two parts, the first focusing on the characterization of male determinants, and the second on factors external to the S locus. The research of S locus F-box genes was primarily aimed to the identification of such genes in European pear, for which sequence data are still not available; moreover, it allowed also to investigate about the S locus structure in the Pyrinae. The analysis was carried out on a pool of varieties of the three species Pyrus communis (European pear), Pyrus pyrifolia (Japanese pear), and Malus × domestica (apple); varieties carrying S haplotypes whose RNases are highly similar were chosen, in order to check whether or not the same level of similarity is maintained also between the male determinants. A total of 82 sequences was obtained, 47 of which represent the first S-locus F-box genes sequenced from European pear. The sequence data strongly support the hypothesis that the S locus structure is conserved among the three species, and presumably among all the Pyrinae; at least five genes have homologs in the analysed S haplotypes, but the number of F-box genes surrounding the S-RNase could be even greater. The high level of sequence divergence and the similarity between alleles linked to highly conserved RNases, suggest a shared ancestral polymorphism also for the F-box genes. The F-box genes identified in European pear were mapped on a segregating population of 91 individuals from the cross 'Abbé Fétel' × 'Max Red Bartlett'. All the genes were placed on the linkage group 17, where the S locus has been placed both in pear and apple maps, and resulted strongly associated to the S-RNase gene. The linkage with the RNase was perfect for some of the F-box genes, while for others very rare single recombination events were identified. The second part of this study was focused on the research of other genes involved in the SI response in pear; it was aimed on one side to the identification of genes differentially expressed in compatible and incompatible crosses, and on the other to the cloning and characterization of the transglutaminase (TGase) gene, whose role may be crucial in pollen rejection. For the identification of differentially expressed genes, controlled pollinations were carried out in four combinations (self pollination, incompatible, half-compatible and fully compatible cross-pollination); expression profiles were compared through cDNA-AFLP. 28 fragments displaying an expression pattern related to compatibility or incompatibility were identified, cloned and sequenced; the sequence analysis allowed to assign a putative annotation to a part of them. The identified genes are involved in very different cellular processes or in defense mechanisms, suggesting a very complex change in gene expression following the pollen/pistil recognition. The pool of genes identified with this technique offers a good basis for further study toward a better understanding of how the SI response is carried out. Among the factors involved in SI response, moreover, an important role may be played by transglutaminase (TGase), an enzyme involved both in post-translational protein modification and in protein cross-linking. The TGase activity detected in pear styles was significantly higher when pollinated in incompatible combinations than in compatible ones, suggesting a role of this enzyme in the abnormal cytoskeletal reorganization observed during pollen rejection reaction. The aim of this part of the work was thus to identify and clone the pear TGase gene; the PCR amplification of fragments of this gene was achieved using primers realized on the alignment between the Arabidopsis TGase gene sequence and several apple EST fragments; the full-length coding sequence of the pear TGase gene was then cloned from cDNA, and provided a precious tool for further study of the in vitro and in vivo action of this enzyme.

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Diego e José de Figueroa y Córdoba furono due fratelli drammaturghi, attivi nella seconda metà del XVII secolo, che praticarono assiduamente la scrittura in collaborazione. Nel tentativo di rivalutare questi autori ingiustamente dimenticati dalla critica odierna, il presente lavoro si propone di offrire uno studio introduttivo alle figure e al teatro dei due fratelli. Nella prima parte, si offre un profilo biografico dei fratelli Figueroa, riunendo le seppur scarse notizie che possediamo sulla loro vita, in modo da inquadrarne le personalità all’interno degli ambienti letterari dell’epoca. Ci si concentra, poi, sul corpus, proponendo una panoramica delle commedie scritte da Diego e José, dando di ciascuna una breve sinossi e un rapido inquadramento all’interno dei generi tipici del teatro aureo, e segnalando gli eventuali problemi di attribuzione. Si accenna, infine, alla collaborazione dei fratelli nella scrittura di molte delle loro commedie, avanzando alcune ipotesi sulla tecnica compositiva. La seconda parte è costituita da un repertorio bibliografico del teatro “maggiore” dei due fratelli, in cui si descrivono analiticamente tutti gli esemplari conosciuti delle comedias dei Figueroa. Ogni descrizione si completa con una lista delle biblioteche in cui l’esemplare è conservato, lista compilata attraverso la consultazione di cataloghi, cartacei e on-line, delle principali biblioteche con fondi di teatro spagnolo del Siglo de Oro. Infine, la terza parte è dedicata all’edizione critica di una delle commedie scritte in collaborazione da Diego e José: Mentir y mudarse a un tiempo, condotta usando come testo base un manoscritto probabilmente autografo. L’edizione si completa di un apparato critico, con analisi dei testimoni, stemma codicum e registro delle varianti. Precede l’edizione uno studio generale introduttivo all’opera.

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La tesi di Marco Perez intitolata “Luis Arana e i veterani di Euzkeldun Batzokija: la corrente ortodossa del nazionalismo basco”, può essere considerata come la biografia politica di uno dei personaggi più importanti del nazionalismo basco. Il lavoro di ricerca si centra fondamentalmente sull'ispiratore del nazionalismo euskaldun (e cofondatore del Partido Nacionalista Vasco) e della corrente che ne accompagnò e sostenne l'azione politica. Euzkeldun Batzokija fu il nome dato al primo circolo del PNV, fondato da Luis e Sabino Arana nel 1894. Successivamente, gli statuti del circolo e i suoi membri veterani furono presi come modello del nazionalismo primordiale (che si pretendeva definire sull'esempio dell'Ordine gesuita). Sul piano organizzativo la tesi si divide in sette capitoli che ricostruiscono il percorso politico di Luis Arana, dai primi documenti del 1879 fino alle ultime lettere inviate negli anni quaranta. Si tratta di un lungo periodo, che comprende momenti diversi della storia spagnola (dalle guerre carliste alla Guerra Civile spagnola) e del movimento aranista. In questo senso, sulla base di una generale e comparata riflessione sul nazionalismo, si analizza il movimento basco nei suoi rapporti con la modernità. Una realazione costruita attraverso concetti “diacronicamente” legati a un passato mitico e leggendario e comunque subalterna ai rapporti di forza tra le correnti del PNV. La corrente ortodossa fece sempre riferimento al nazionalismo “originario” (definito dai fratelli Arana nei primi anni del movimento) che fu un'espressione regionale del nazionalcattolicesimo spagnolo. Fu proprio Luis Arana a ricordare la finalità religiosa ed etnica del nazionalismo basco, respingendo qualsiasi aggiornamento teorico e organizzativo del PNV, intesi come una grave violazione dell'ortodossia aranista.

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I disturbi dello spettro autistico (DSA) ed il ritardo mentale (RM) sono caratterizzati da un’eziologia genetica complessa ed eterogenea. Grazie ai recenti sviluppi nella ricerca genomica, è stato possibile dimostrare il ruolo di numerose copy number variants (CNVs) nella patogenesi di questi disturbi, anche se nella maggior parte dei casi l’eziologia rimane ancora sconosciuta. Questo lavoro riguarda l’identificazione e la caratterizzazione dei CNVs in famiglie con DSA e RM. E’ stata studiata una microdelezione in 7q31 che coinvolge i geni IMMP2L e DOCK4, trasmessa dalla madre con dislessia a due figli con autismo ed una figlia con dislessia. Nella stessa famiglia segrega una seconda microdelezione in 2q14 che inattiva il gene CNTNAP5 ed è trasmessa dal padre (con tratti autistici) ai due figli con autismo. Abbiamo quindi ipotizzato che i geni DOCK4 e CNTNAP5 potessero essere implicati, rispettivamente, nella suscettibilità a dislessia e DSA. Lo screening di numerosi individui affetti ha supportato la nostra ipotesi, con l’identificazione di una nuova microdelezione di DOCK4 che segrega con la dislessia, e 3 nuove varianti missenso in CNTNAP5 in individui con autismo. Dall’analisi genomica comparativa su array (aCGH) di individui con RM, è stata identificata una delezione nella regione 7q31.32, che coinvolge il gene CADPS2, in due fratelli con RM e tratti autistici, probabilmente ereditata dalla madre. Lo screening di mutazione di questo gene in individui con autismo o RM, ha portato all’identificazione di 3 varianti non sinonime, assenti nei controlli, ed ereditate per via materna. Poiché CADPS2 risiede in una regione genomica che contiene loci soggetti ad imprinting, abbiamo ipotizzato che il gene CADPS2 possa essere anch’esso caratterizzato da imprinting, con espressione monoallelica materna. Lo studio di espressione di CADPS2 in cellule del sangue ha avvalorato questa ipotesi, implicando perciò CADPS2 come un nuovo gene di suscettibilità per il RM e DSA.

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L’overespressione dei geni EVI1(3q26) e PRDM16(1p36), è descritta sia in presenza che in assenza di riarrangiamenti 3q26 e 1p36 in specifici sottogruppi citogenetici di LAM, ed è associata ad una prognosi sfavorevole. Lo scopo principale del nostro studio è stato identificare e caratterizzare tramite FISH e RQ-PCR, alterazioni di EVI1 e PRDM16 in pazienti con alterazioni cromosomiche 3q e 1p.Riarrangiamenti di EVI1 si associavano ad alterazioni cromosomiche 3q26, ma, in 6 casi (6/35;17,1%) erano presenti in assenza di coinvolgimenti, in citogenetica convenzionale, della regione 3q26, a causa di meccanismi complessi e/o alterazioni ‘criptiche’. Inoltre, abbiamo identificato quattro nuovi riarrangiamenti di EVI1, tra cui due nuove traslocazioni simili presenti in due fratelli. Riarrangiamenti e/o amplificazioni di PRDM16 erano spesso associate ad alterazioni 1p36 (7/14;50%). L’analisi di EVI1 e PRDM16 è stata estesa ad altri casi con alterazioni -7/7q-, con cariotipo normale, con alterazioni 3q per PRDM16 e con alterazioni 1p per EVI1. L’overespressione di EVI1 era presente solo nel gruppo -7/7q- (10/58;17.2%) ed in un caso si associava ad amplificazione genica, mentre PRDM16 era overespresso in casi di tutti i gruppi analizzati,sia con cariotipi complessi, dove si associava in alcuni casi ad amplificazione genica, sia con cariotipi normali o con singole alterazioni. Il nostro studio dimostra come la FISH permetta di identificare alterazioni dei geni EVI1 e PRDM16, anche in assenza di coinvolgimenti delle regioni 3q26 e 1p36. Riarrangiamenti complessi e/o una scarsa qualità dei preparati citogenetici sono le cause principali per la mancata identificazione di queste alterazioni. La RQ-PCR permette di identificare l’overespressione anche nei casi in cui non sia dovuta ad alterazioni citogenetiche. È importante confermare con FISH e/o RQ-PCR il coinvolgimento di questi due geni, per individuare alla diagnosi pazienti con prognosi sfavorevole e che potranno beneficiare di terapie maggiormente aggressive e/o di trapianto allogenico di cellule staminali.

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Approaching the world of the fairy tale as an adult, one soon realizes that things are not what they once seemed during story time in bed. Something that once appeared so innocent and simple can become rather complex when digging into its origin. A kiss, for example, can mean something else entirely. I can clearly remember my sister, who is ten years older than I am, telling me that the fairy tales I was told had a mysterious hidden meaning I could not understand. I was probably 9 or 10 when she told me that the story of Sleeping Beauty, which I used to love so much in Disney’s rendering, was nothing more than the story of an adolescent girl, with all the necessary steps needed to become a woman, the bleeding of menstruation and the sexual awakening - even though she did not really put it in these terms. This shocking news troubled me for a while, so much so that I haven’t watched that movie since. But in reality it was not fear that my sister had implanted in me: it was curiosity, the feeling that I was missing something terribly important behind the words and images. But it was not until last year during my semester abroad in Germany, where I had the chance to take a very interesting English literature seminar, that I fully understood what I had been looking for all these years. Thanks to what I learned from the work of Bruno Bettelheim, Jack Zipes, Vladimir Propp, and many other authors that wrote extensively about the subject, I feel I finally have the right tools to really get to know this fairy tale. But what I also know now is that the message behind fairy tales is not to be searched for behind only one version: on the contrary, since they come from oral traditions and their form was slowly shaped by centuries of recountals and retellings, the more one digs, the more complete the understanding of the tale will be. I will therefore look for Sleeping Beauty’s hidden meaning by looking for the reason why it did stick so consistently throughout time. To achieve this goal, I have organized my analysis in three chapters: in the first chapter, I will analyze the first known literary version of the tale, the French Perceforest, and then compare it with the following Italian version, Basile’s Sun, Moon, and Talia; in the second chapter, I will focus on the most famous and by now classical literary versions of Sleeping Beauty, La Belle Au Bois Dormant, written by the Frenchman, Perrault, and the German Dornröschen, recorded by the Brothers Grimm’s; finally, in the last chapter, I will analyze Almodovar’s film Talk to Her as a modern rewriting of this tale, which after a closer look, appears closely related to the earliest version of the story, Perceforest.

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Psychogenetic research has emphasised the influence of social factors on a child's intellectual development. In her work, Ms. Dumitrascu examines two such factors; family size and order of birth. However, since these formal parameters tend to be unstable, other more informal factors should be taken into consideration. Of these, perhaps the most interesting is the "style" of parental education, which Ms. Dumitrascu regards as an expression of national traditions at the family level. This educational style is culture dependent. Only a comparative, cross-cultural study can reveal the real mechanism through which educational style influences the development of a child's intellect and personality. Ms. Dumitrascu conducted an experimental cross-cultural study aimed at examining the effects of the family environment on a child's intellectual development. Three distinct populations were involved in her investigation, each having quite a distinct status in their geographical area; Romanians, Romanies (Gypsies) from Romania, and Russians from the Republic of Moldova. She presented her research in the form of a series of articles written in English totalling 85 pages, and also on disc. A significant difference was revealed between the intelligence of a child living in a large family, and that of a child with no brothers or sisters. In the case of Romany children, the gap is remarkably large. Ms. Dumitrascu concludes that the simultaneous action of several negative factors (low socio-economic status, large family size, socio-cultural isolation of a population) may delay child development. Subjected to such a precarious environment, Romany children do not seek self-realisation, but rather struggle to survive the hardship. Most of them remain out of civilisation. Unfortunately, adult Romanies seldom express any concern regarding their children's successful social integration. The school as main socialisation tool has no value for most parents. Ms. Dumitrascu argues the need for a major effort aimed at helping Romany's social integration. She hopes this project will be of some help for psychologists, social workers, teachers, and all those who are interested in the integration into society of minority groups.

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The umbilical cord is not an inert structure, suspended between the fetus and placenta, but it plays an active role and it is involved in several processes afflicting the feto-placental unit. Its study has to be regarding not only its morphology and morphometry, and the impendance of blood flow by Doppler waveform analysis, but it includes also an analysis of the coiling type and the amount of the Wharton Jelly. The umbilical cord has been considered like an important and huge source of informations, useful to assess the well-being of the fetus and the outcome of pregnancy. The standardization of ultrasound techniques is the first step to speak the same language and make the study of this structure a fundamental part of well-being fetus assessment. This article is carefully focused on morphologic, morphometric and functional ultrasound examination of umbilical cord and suggests that any anomaly detected should provide an indication for an intense fetal follow-up, useful for early helpful therapy, preventing serious complication for the pregnancy.

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Genetic defects of the Na+-K+-2Cl- (NKCC2) sodium potassium chloride co-transporter result in severe, prenatal-onset renal salt wasting accompanied by polyhydramnios, prematurity, and life-threatening hypovolemia of the neonate (antenatal Bartter syndrome or hyperprostaglandin E syndrome). Herein are described two brothers who presented with hyperuricemia, mild metabolic alkalosis, low serum potassium levels, and bilateral medullary nephrocalcinosis at the ages of 13 and 15 yr. Impaired function of sodium chloride reabsorption along the thick ascending limb of Henle's loop was deduced from a reduced increase in diuresis and urinary chloride excretion upon application of furosemide. Molecular genetic analysis revealed that the brothers were compound heterozygotes for mutations in the SLC12A1 gene coding for the NKCC2 co-transporter. Functional analysis of the mutated rat NKCC2 protein by tracer-flux assays after heterologous expression in Xenopus oocytes revealed significant residual transport activity of the NKCC2 p.F177Y mutant construct in contrast to no activity of the NKCC2-D918fs frameshift mutant construct. However, coexpression of the two mutants was not significantly different from that of NKCC2-F177Y alone or wild type. Membrane expression of NKCC2-F177Y as determined by luminometric surface quantification was not significantly different from wild-type protein, pointing to an intrinsic partial transport defect caused by the p.F177Y mutation. The partial function of NKCC2-F177Y, which is not negatively affected by NKCC2-D918fs, therefore explains a mild and late-onset phenotype and for the first time establishes a mild phenotype-associated SLC12A1 gene mutation.

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Both Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are caused by mutations of the X-linked dystrophin gene. BMD patients are less affected clinically than DMD patients. We present five patients with a diagnosis of BMD. First, two identical twins, with a deletion of exon 48 of the dystrophin gene, who experienced prominent muscle cramps from the age of three. The histopathological examination of muscle biopsies of these two twins revealed only very slight muscle fiber alterations. Second, two brothers who displayed marked, unusual intrafamilial variability of the clinical picture as well as showing a new point mutation in the dystrophin gene. And finally, a fifth boy who displayed a new point mutation in the dystrophin gene. Although he was clinically asymptomatic at the age of 15 and muscle biopsy only showed very minor myopathic signs, serum Creatine Kinase (CK) levels had been considerably elevated for years. Taken together, these cases add to the spectrum of marked discrepancies in clinical, histopathological and molecular genetic findings in BMD.

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Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive disorder in which a nuclear mutation of the thymidine phosphorylase (TP) gene causes mitochondrial genomic dysfunction. Patients suffer from gastrointestinal dysmotility, cachexia, ptosis, external ophthalmoparesis, myopathy and polyneuropathy. Magnetic resonance imaging (MRI) shows leukoencephalopathy. We describe clinical, genetic and neuroradiological features of three brothers affected with MNGIE. Clinical examination, laboratory analyses, MRI and magnetic resonance spectroscopy (MRS) of the brain, and genetic analysis have been performed in all six members of the family with the three patients with MNGIE. Two of them are monozygous twins. They all suffered from gastrointestinal dysmotility, cachexia, ophthalmoplegia, muscular atrophies, and polyneuropathy. Urinary thymidine was elevated in the patients related to the severity of clinical disease, and urinary thymidine (normally not detectable) was also found in a heterozygous carrier. Brain MRI showed leukoencephalopathy in all patients; however, their cognitive functioning was normal. Brain MRS demonstrated reduced N-acetylaspartate and choline in severely affected areas. MRI of heterozygous carriers was normal. A new mutation (T92N) in the TP gene was identified. Urinary thymidine is for the first time reported to be detectable in a heterozygous carrier. MRS findings indicate loss of neurons, axons, and glial cells in patients with MNGIE, but not in heterozygous carriers.