Two new Rett syndrome families and review of the literature: expanding the knowledge of MECP2 frameshift mutations

<p>Abstract</p> <p>Background</p> <p>Rett syndrome (RTT) is an X-linked dominant neurodevelopmental disorder, which is usually caused by <it>de novo </it>mutations in the <it>MECP2 </it>gene. More than 70% of the disease causing <it>MECP2 </it>mutations are eight recurrent C to T transitions, which almost exclusively arise on the paternally derived X chromosome. About 10% of the RTT cases have a C-terminal frameshift deletion in <it>MECP2</it>. Only few RTT families with a segregating <it>MECP2 </it>mutation, which affects female carriers with a phenotype of mental retardation or RTT, have been reported in the literature. In this study we describe two new RTT families with three and four individuals, respectively, and review the literature comparing the type of mutations and phenotypes observed in RTT families with those observed in sporadic cases. Based on these observations we also investigated origin of mutation segregation to further improve genetic counselling.</p> <p>Methods</p> <p><it>MECP2 </it>mutations were identified by direct sequencing. XCI studies were performed using the X-linked androgen receptor (<it>AR</it>) locus. The parental origin of <it>de novo MECP2 </it>frameshift mutations was investigated using intronic SNPs.</p> <p>Results</p> <p>In both families a C-terminal frameshift mutation segregates. Clinical features of the mutation carriers vary from classical RTT to mild mental retardation. XCI profiles of the female carriers correlate to their respective geno-/phenotypes. The majority of the <it>de novo </it>frameshift mutations occur on the paternally derived X chromosome (7/9 cases), without a paternal age effect.</p> <p>Conclusions</p> <p>The present study suggests a correlation between the intrafamilial phenotypic differences observed in RTT families and their respective XCI pattern in blood, in contrast to sporadic RTT cases where a similar correlation has not been demonstrated. Furthermore, we found <it>de novo MECP2 </it>frameshift mutations frequently to be of paternal origin, although not with the same high paternal occurrence as in sporadic cases with C to T transitions. This suggests further investigations of more families. This study emphasizes the need for thorough genetic counselling of families with a newly diagnosed RTT patient.</p

Adapting Yeast as Model to Study Ricin Toxin A Uptake and Trafficking‡

The plant A/B toxin ricin represents a heterodimeric glycoprotein belonging to the family of ribosome inactivating proteins, RIPs. Its toxicity towards eukaryotic cells results from the depurination of 28S rRNA due to the N-glycosidic activity of ricin toxin A chain, RTA. Since the extention of RTA by a mammalian-specific endoplasmic reticulum (ER) retention signal (KDEL) significantly increases RTA in vivo toxicity against mammalian cells, we here analyzed the phenotypic effect of RTA carrying the yeast-specific ER retention motif HDEL. Interestingly, such a toxin (RTAHDEL) showed a similar cytotoxic effect on yeast as a corresponding RTAKDEL variant on HeLa cells. Furthermore, we established a powerful yeast bioassay for RTA in vivo uptake and trafficking which is based on the measurement of dissolved oxygen in toxin-treated spheroplast cultures of S. cerevisiae. We show that yeast spheroplasts are highly sensitive against external applied RTA and further demonstrate that its toxicity is greatly enhanced by replacing the C-terminal KDEL motif by HDEL. Based on the RTA resistant phenotype seen in yeast knock-out mutants defective in early steps of endocytosis (∆end3) and/or in RTA depurination activity on 28S rRNA (∆rpl12B) we feel that the yeast-based bioassay described in this study is a powerful tool to dissect intracellular A/B toxin transport from the plasma membrane through the endosomal compartment to the ER

Role of the Mannose Receptor (CD206) in Innate Immunity to Ricin Toxin

The entry of ricin toxin into macrophages and certain other cell types in the spleen and liver results in toxin-induced inflammation, tissue damage and organ failure. It has been proposed that uptake of ricin into macrophages is facilitated by the mannose receptor (MR; CD206), a C-type lectin known to recognize the oligosaccharide side chains on ricin’s A (RTA) and B (RTB) subunits. In this study, we confirmed that the MR does indeed promote ricin binding, uptake and killing of monocytes in vitro. To assess the role of MR in the pathogenesis of ricin in vivo, MR knockout (MR−/−) mice were challenged with the equivalent of 2.5× or 5× LD50 of ricin by intraperitoneal injection. We found that MR−/− mice were significantly more susceptible to toxin-induced death than their age-matched, wild-type control counterparts. These data are consistent with a role for the MR in scavenging and degradation of ricin, not facilitating its uptake and toxicity in vivo

AB Toxins: A Paradigm Switch from Deadly to Desirable

To ensure their survival, a number of bacterial and plant species have evolved a common strategy to capture energy from other biological systems. Being imperfect pathogens, organisms synthesizing multi-subunit AB toxins are responsible for the mortality of millions of people and animals annually. Vaccination against these organisms and their toxins has proved rather ineffective in providing long-term protection from disease. In response to the debilitating effects of AB toxins on epithelial cells of the digestive mucosa, mechanisms underlying toxin immunomodulation of immune responses have become the focus of increasing experimentation. The results of these studies reveal that AB toxins may have a beneficial application as adjuvants for the enhancement of immune protection against infection and autoimmunity. Here, we examine similarities and differences in the structure and function of bacterial and plant AB toxins that underlie their toxicity and their exceptional properties as immunomodulators for stimulating immune responses against infectious disease and for immune suppression of organ-specific autoimmunity

Threat to information security : the system vulnerability and denial of service attacks

The use of the Internet has increased drastically the last few years. This trend has led to a constant increase in attacks toward computer systems and networks, and the methods for attacking are becoming more and more advanced. By this, we mean that new tools are developing in a way that makes it more difficult for people to protect themselves against, while the use of the tools is more user friendly than before, and the hackers do not need as much skills as they used to. In order for security practitioners to know how to protect themselves against new attacks, it is important for them to know how the hackers work and think. Therefore, we have described the hacker environment, tried to map how many they are, how they find information, and how they share information. Vulnerabilities and denial of service are considered to be the main parts of the report, with a model to each case. To get an overview over vulnerabilities and factors that influence vulnerabilities, a system dynamics model is discussed. The model shows variables like vulnerable hosts, patching, hackers with or without scripts, sophisticated and nonsophisticated hackers, attacks, and attack frequency. This is an overall description of a single vulnerability problem, but the problem with multiple vulnerabilities is also briefly discussed. Some of the biggest threats when it comes to information security today are denial of service (DoS) attacks and distributed denial of service (DDoS) attacks. DoS and DDos attacks are possible to be the most potent and difficult to tackle, and they can do enormous damages. These types of attacks are described, and we use and discuss a model over a specific denial of service case. The case is about a turf war between the two German hackers “Mixter” and “Randomizer”, and the model includes variables that are specific to the case, and variables that are more general about hackers and the Internet world. As we have been working with the master thesis, a big problem has been data collection. This has been a problem for us because it is hard to find data on information security. Some organizations choose not to publicize of different reasons, this can be that they are afraid of bad publicity. It takes a lot of time and effort to do this kind of data collection, and people who do it, collect for a narrow purpose. Systematically collected data is therefore not always available

The garden in the apple orchard : the good story toward a greener future

Som følge av et sterkt politisk fokus på fortetting i og rundt byer i Norge de siste 20 årene, har småhusområdene rundt Oslo sentrum også vært gjenstand for store endringer. Dette studiet tar for seg problematikken rundt hva som skjer med kvaliteten i de nye hagene som dannes når de store gamle eplehagene forvandles og fortettes med 5 til 10 nye boligenheter. Det har blitt lagt vekt på å finne ut om det eksisterer en «tommelfingerregel» for hva det koster å bygge et uteareal og om det er noen sammenheng mellom kostnaden og kvaliteten i det som faktisk bygges. Videre har det vært viktig å avklare bevisstheten omkring utearealet hos utbyggere, eiendomsmeglere og kjøpere av disse boligprosjektene, for å se hvordan dette påvirker kvalitetsoppfattelsen av de ferdig bygde utearealene. For å løse denne oppgaven har det blitt gjennomført et casestudie av 27 tilfeldig utvalgte småhusprosjekter i Oslo vest, for deretter å analysere sammenhenger. Videre er det foretatt kvalitative intervjuer av utbyggerne bak 80 % av de utvalgte prosjektene. Dette er supplert med en kvantitativ spørreundersøkelse blant 218 beboere og 11 eiendomsmeglere som var relatert til de utvalgte prosjektene. Studiet har avdekket et gjennomsnittlig kostnadsnivå på kr 1.635,- pr kvadratmeter uteareal ved bygging av småhus i tidligere eplehager. Det er konkludert med at det er en manglende bevissthet i byggebransjen omkring grensesnitt og kostnad av et uteareal. Som følge av dette er det avdekket et behov for en systematisk innarbeidet metode for å beregne utearealets prosentvise andel av boligens totale byggekostnad. Ved å ha et slikt parameter vil bransjen generelt kunne ha samme oppfattelse av hvor mye et uteareal bør koste og hvordan denne kostnaden påvirker kvaliteten i utearealet. Studiet påviser også at det er sammenhenger mellom utearealets byggekostnad og hvilken kvalitetsoppfattelse beboerne har av sin hage. Det er ikke nødvendigvis slik at en høy kostnad medfører en god kvalitetsoppfattelse, men en tydeliggjøring av ressursbruken er viktig og vil kunne påvirke resultatet. Det er påvist en lav eller manglende bevissthet blant kjøpere om hva de kan og bør forvente av et godt uteareal. Kjøperne er avhengige av tidlig og konsistent informasjon om produktet de kjøper og eiendomsmeglernes kunnskap og bevissthet omkring utearealet vil derfor være avgjørende. Den «gode historien» om utearealet uteblir fra eiendomsmeglerne, som følge av at de besitter begrenset informasjon fra utbygger i salgsprosessen. Det konkluderes derfor med at det er behov for ytterligere bevisstgjøring gjennom informasjon, kommunikasjon og tydeliggjøring. En enhetlig metode for å måle den ferdig bygde kvaliteten i utearealet vil redusere tvil om hvilke krav som ligger til grunn. Dette må følges opp gjennom krav til fagmessig utførelse, etterkontroll og etableringsskjøtsel.As a result of a strong political focus on densification in and around Norwegian cities during the last 20 years, the neighborhoods of single-family dwellings around the center of Oslo have also undergone major changes. This study deals with the problems concerning the evolving quality of the new garden areas that are created when former large apple orchards are transformed and densified into 5 to 10 new residential units. Emphasis has been given to determining whether there is any “rule of thumb” regarding the costs of constructing a garden area and whether there is any correlation between the cost and the quality of what is actually built. It has also been important to define more clearly the awareness of the garden area among developers, real estate agents, and buyers of these residential projects, in order to see how this affects the perception of the quality of the garden areas after completed construction. To address this task, a case study was completed of 27 randomly selected single-family home projects in Oslo West, thereafter to analyze relationships. Qualitative interviews were also undertaken with the developers behind 80% of the selected projects. This information is supplemented by a quantitative survey among 218 residents and 11 real estate agents involved in the selected projects. The study has disclosed an average cost level of NOK 1,635.00 per square meter of garden area for small homes being built in former apple orchards. Further, it has been concluded that there is inadequate awareness within the building industry of the interaction with and cost of an outdoor or garden area. Consequently, a need is seen for a systematic method for calculating the garden area’s percentage of the total building cost of the home. Such a parameter could enable the building industry generally to have the same understanding of how much an outdoor garden area should cost and how this cost affects the quality of the outdoor area. The study also shows correlations between the construction cost of the garden area and the resident’s perception of the quality of his garden. It is not necessarily the case that a high cost will result in a perception of good quality, but a clarification of the resource use is important and could affect the result. There is found a low or insufficient awareness among buyers with regard to what they can and should expect of a good outdoor area. The customers are dependent on early and consistent information about the product that they are buying, and the real estate agent’s knowledge and awareness pertaining to the outdoor area will therefore be crucial. The “good story” about the garden area is not being told by the real estate agents due to the fact that they have acquired only limited information from developers during the sales process. It is therefore concluded that there is a need for a further increase in awareness through information, communication and clarification. A uniform method for measuring the quality of the finished outdoor area will reduce uncertainty regarding the requirements upon which the project is based. This must be followed up through requirements for professional workmanship, quality control and establishment care.M-EUT

Impact of urban morphology on pressure coefficient on building facades and wind velocity in street canyons: The case of Oslo

This thesis aims to study how the pressure coefficients and wind velocity will vary within the city of Oslo, with changing urban morphology and aspect ratios. It is common in the modern society to erect high-rise buildings in front of already existing buildings. The study will simulate and investigate how this will impact the wind conditions in the existing urban environment. To achieve this simulation, a CFD tool, Star CCM+ has been used. The geometry that have been used in Star CCM+ is originally gathered from Kartverket and is a SOSI file. A workflow of several programs was needed to finally import this SOSI file as a file format compatible with Star CCM+. An area from Barcode and to Løren in Oslo was chosen, as this has several kinds of urban areas, involving high-rise buildings, low-rise buildings, and older high-rise buildings. This geometry is divided in five different regions to fit Star CCM+ restrictions regarding domain size. An important part of this study was to achieve a good mesh solution and apply appropriate physics setting. Pressure coefficients does vary from region to region, Region 1 with high-rise buildings vary more internally in the region than Region 3 where the building mass is lower and much denser. It is also clear that the velocity is dependent on how dense the buildings are located and the aspect ratio of the streets and buildings

Neural Network for Recognizing Features in Music

Gjennom de siste to tiårene har det blitt gjort stor fremgang rundt identifisering og klassifisering av trekk og egenskaper i musikk, gjennom bruk av fremgangsmåter som neural networks og maskinlæring. Til tross for dette er feltet fremdeles under utvikling, og det er en mangel på samlede implementeringer som dekker både beat-identifisering og akkord-klassifisering. Som en del av denne avhandlingen gjøres forsøk på å bruke og kombinere eksisterende verktøy, bibliotek og modeller innen feltet for å trekke ut data rundt tempo og akkorder i musikk. Selv om perfekt identifisering og klassifisering ikke er oppnåelig, gjøres en undersøkelse av fordeler og ulemper av klassiske algoritmer, Hidden Markov modeller og neural networks. Denne undersøkelsen har formålet å finne den beste løsningen gitt begrensningene satt ut i oppgaven. Ideer for hvordan løsningen kan forbedres utenfor slike begrensninger er også utforsket. En algoritmisk tilnærming for analyse av onset styrke ble valgt for identifisering av beats. For akkorder ble en randomisert implementasjon av grid search gjort på et neural network som fødtes med forprosessert lyddata uten vokaler. Gjennom denne tilnærmingen ble top-1 nøyaktighet på 82% oppnådd for akkord-klassifisering, klart overlegen det algoritme-baserte løsninger klarte