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Background: Focal cortical dysplasias (FCDs) are congenital structural abnormalities of the brain, and represent the most common cause of medication-resistant focal epilepsy in children and adults. Recent studies have shown that somatic mutations (i.e. mutations arising in the embryo) in mTOR pathway genes underlie some FCD cases. Specific therapies targeting the mTOR pathway are available. However, testing for somatic mTOR pathway mutations in FCD tissue is not performed on a clinical basis, and the contribution of such mutations to the pathogenesis of FCD remains unknown. Aim: To investigate the feasibility of screening for somatic mutations in resected FCD tissue and determine the proportion and spatial distribution of FCDs which are due to low-level somatic mTOR pathway mutations. Methods: We performed ultra-deep sequencing of 13 mTOR pathway genes using a custom HaloPlexHS target enrichment kit (Agilent Technologies) in 16 resected histologically-confirmed FCD specimens. Results: We identified causal variants in 62.5% (10/16) of patients at an alternate allele frequency of 0.75–33.7%. The spatial mutation frequency correlated with the FCD lesion’s size and severity. Conclusions: Screening FCD tissue using a custom panel results in a high yield, and should be considered clinically given the important potential implications regarding surgical resection, medical management and genetic counselling.
Despite established clinical associations among major depression (MD), alcohol dependence (AD), and alcohol consumption (AC), the nature of the causal relationship between them is not completely understood. We leveraged genome-wide data from the Psychiatric Genomics Consortium (PGC) and UK Biobank to test for the presence of shared genetic mechanisms and causal relationships among MD, AD, and AC.
Linkage disequilibrium score regression and Mendelian randomization (MR) were performed using genome-wide data from the PGC (MD: 135 458 cases and 344 901 controls; AD: 10 206 cases and 28 480 controls) and UK Biobank (AC-frequency: 438 308 individuals; AC-quantity: 307 098 individuals).
Positive genetic correlation was observed between MD and AD (rgMD−AD = + 0.47, P = 6.6 × 10−10). AC-quantity showed positive genetic correlation with both AD (rgAD−AC quantity = + 0.75, P = 1.8 × 10−14) and MD (rgMD−AC quantity = + 0.14, P = 2.9 × 10−7), while there was negative correlation of AC-frequency with MD (rgMD−AC frequency = −0.17, P = 1.5 × 10−10) and a non-significant result with AD. MR analyses confirmed the presence of pleiotropy among these four traits. However, the MD-AD results reflect a mediated-pleiotropy mechanism (i.e. causal relationship) with an effect of MD on AD (beta = 0.28, P = 1.29 × 10−6). There was no evidence for reverse causation.
This study supports a causal role for genetic liability of MD on AD based on genetic datasets including thousands of individuals. Understanding mechanisms underlying MD-AD comorbidity addresses important public health concerns and has the potential to facilitate prevention and intervention efforts.
A computerized systetn, consisting of a fluorescence x-ray source (Philips), an Si (Li) detector (Ortec), and a mini Computer (Xerox) is currentiy in operation at The University of Texas M. D. Anderson Hospital and Tumor Institute, Experimentel Pathology Section, for the analysis of trace elements in biological specimens. The elements of interest are Fe, Cu, and Zn for possible significance in the detection and study of cancer. The detection system is being used for comparatively routine analysis of these elements, which are present in blood serum in the ppM range. With appropriate sample preparation techniques, using 1 ml of serum, the limit of detectability for these elements is estimated to be 100 ppB (1 in 107). Further refinement is possible, and research in this direction continues.
The computerized fluorescence radiation induced energy dispersive analyzer (FRIEDA) (1) described earlier uses an x-ray beam with a well defined energy for the excitation of fluorescence radiation, and an Si(Li) detector to measure the total x-ray spectra emitted. Such a system can also simultaneously provide supplemental data for the determination of the dry mass and the sample mass absorption which is necessary for accurate quantitation of the results. This instrumental capabillty has been utilized in the measurement of the trace elements iron, copper, and zinc in serum.
Known amounts of two elements are thoroughly mixed with the sample. One element has a ‘high energy’ K line, the other a ‘low energy’ K line. The ratio of these intensities, in the absence of absorption, is a known constant and dependent only on the relative amounts of the respective elements, and on the energy of the exciting radiation. Whenever absorption is present, the ratio will change in a manner directly related to the mass absorption of the sample for these radiations.
To evaluate the clinicopathological and mycological manifestations of fungal rhinosinusitis occurring in the Tengku Ampuan Rahimah Hospital, in Klang, Malaysia, which has a tropical climate.
Records of patients treated from 2009 to 2016 were analysed retrospectively. Data from the records were indexed based on age, gender, clinical presentations, symptom duration, clinical signs and mycological growth.
Of 80 samples, 27 (33.75 per cent) had fungal growth. Sixteen patients were classified as having non-invasive fungal rhinosinusitis and 11 as having invasive fungal rhinosinusitis. The commonest clinical presentation was nasal polyposis in non-invasive fungal rhinosinusitis patients (p < 0.05) and ocular symptoms in invasive fungal rhinosinusitis patients (p < 0.05). The commonest organism was aspergillus sp. (p < 0.05) in non-invasive fungal rhinosinusitis and mucorales in invasive fungal rhinosinusitis.
There is an almost equal distribution of both invasive and non-invasive fungal rhinosinusitis, as seen in some Asian countries. Invasive fungal rhinosinusitis, while slightly uncommon when compared to non-invasive fungal rhinosinusitis, is potentially life threatening, and may require early and extensive surgical debridement. The clinical presentation of nasal polyposis was often associated with non-invasive fungal rhinosinusitis, whereas ocular symptoms were more likely to be associated with invasive fungal rhinosinusitis.
Investigations on the relationship between sweet taste perception and body mass index (BMI) have been inconclusive. Here, we report a longitudinal analysis using a genetically informative sample of 1,576 adolescent Australian twins to explore the relationship between BMI and sweet taste. First, we estimated the phenotypic correlations between perception scores for four different sweet compounds (glucose, fructose, neohesperidine dihydrochalcone (NHDC), and aspartame) and BMI. Then, we computed the association between adolescent taste perception and BMI in early adulthood (reported 9 years later). Finally, we used twin modeling and polygenic risk prediction analysis to investigate the genetic overlap between BMI and sweet taste perception. Our findings revealed that BMI in early adulthood was significantly associated with each of the sweet perception scores, with the strongest correlation observed in aspartame with r = 0.09 (p = .007). However, only limited evidence of association was observed between sweet taste perception and BMI that was measured at the same time (in adolescence), with the strongest evidence of association observed for glucose with a correlation coefficient of r = 0.06 (p = .029) and for aspartame with r = 0.06 (p = .035). We found a significant (p < .05) genetic correlation between glucose and NHDC perception and BMI. Our analyses suggest that sweet taste perception in adolescence can be a potential indicator of BMI in early adulthood. This association is further supported by evidence of genetic overlap between the traits, suggesting that some BMI genes may be acting through biological pathways of taste perception.
Sublingual immunotherapy in patients with allergic rhinitis sensitised to house dust mites is safe, but its efficacy is controversial and sublingual immunotherapy with Blomia tropicalis has not yet been studied. This study sought to evaluate the efficacy of sublingual immunotherapy with house dust mite extract in children and adults with house dust mite allergic rhinitis over a period of two years.
A prospective observational study was conducted of children and adults diagnosed with house dust mite allergic rhinitis who were treated with sublingual immunotherapy from 2008 to 2012. Total Nasal Symptom Scores, Mini Rhinoconjunctivitis Quality of Life scores and medication usage scores were assessed prospectively.
Thirty-nine patients, comprising 24 children and 15 adults, were studied. Total Nasal Symptom Scores and Mini Rhinoconjunctivitis Quality of Life scores dropped significantly at three months into therapy, and continued to improve. Medication usage scores improved at one year into immunotherapy.
Sublingual immunotherapy with house dust mite extracts, including B tropicalis, is efficacious as a treatment for patients with house dust mite allergic rhinitis.
Tungsten oxide (WO3) films were prepared by using magnetron sputtering. Substrate temperature and sputtering pressure were adjusted to vary the microstructure. The films were found to contain nanoclusters; while their size L, and porosity θ and surface roughness zRMS of the film can be varied. After adding a palladium coating on the film surface, the hydrogen (H2) sensing properties of the films, including sensitivity of detection, response time and recovery time were measured. Their dependences on L, θ and zRMS were analyzed and interpreted. The information achieved is useful for improving H2 sensor technology.
We perform a theoretical evaluation of the strain field in a p-channel transistor with silicongermanium (Si1−yGey) stressors in the source and drain regions. The strain field comprises a lateral compressive strain component and a vertical tensile strain component. The lateral strain component is larger in magnitude and more uniformly distributed as compared to the vertical strain component. The impact of transistor design parameters, such as the Ge mole fraction y in the stressors, the spacing L between stressors, the stressor depth, and the raised stressor height, on the strain field are investigated. Hole mobility enhancement larger than 30% is achievable wth L = 50 nm and y = 0.15. More aggressive mobility enhancement targets may be achievable by reducing the stressor spacing and employing a stressor with a larger lattice mismatch with the Si channel.
We report the integration of six levels of Cu interconnects using dual inlaid patterning in a 0.2 μm logic technology. A review of process technology as well as device performance shortcomings using conventional aluminum metallization has been presented. Two tantalum based barriers, TaNx and Ta-Si-N as well as a titanium based barrier, CVD TiN, have been evaluated for their applicability. The use of embedded barriers wherein the barrier is formed below the surface of the dielectric has also been discussed as a potential option. No degradation to the device front-end parametrics were found with the choice of an appropriate barrier. Planarization by Cu CMP introduces surface topography that needs to be minimized in order to process multiple levels of interconnects within specified sheet resistance distributions for a range of line widths. Excellent results with highly planarized levels of metallization have consistently been achieved through an optimization of the unit processes and device integration.
The Interactive Nano-Visualization for Science and Engineering Education (IN-VSEE) project at Arizona State University (ASU) has developed a remotely operable scanning probe microscope (SPM), a visualization gallery of images, and a number of educational modules with materials themes. It exploits the incredible potential of materials science for teaching at the high school and college level about fundamental concepts that cross traditionally separated disciplines. The packing of spheres is a topic that is ideal for linking together the different science and engineering disciplines because of the ubiquity and relevance of spheres in the materials world and the universality of the rules that govern their packing over a large range of sizes. Students can perform a number of discovery-based learning activities, over the web by simultaneously using IN-VSEE's web-accessible module (e.g., The Music of Spheres) and by accessing the remotely-operable SPM for experimenting with nanosphere samples that they prepare. With these resources students can pose materials questions and are empowered to design their experiments to increase their understanding of real materials. The fundamental concepts (e.g., packing geometry, density, surface composition, long-range/short-range ordering, intermolecular forces, etc.) they learn through these materials science experiments are applicable to many other curricular, research, and technology areas.
This chapter focuses on the fabrication and characterization of a microcage for biopsy applications. A microcage based on a free-standing film could be opened/closed through substrate heating with a maximum temperature of 90 °C, or Joule heating with a power less than 5 mW and a maximum response frequency of 300 Hz. A TiNi/diamond-like-carbon (DLC) microcage has been designed, analyzed, fabricated and characterized. The bimorph structure is composed of a top layer of TiNi film and a bottom layer of highly compressively stressed DLC for upward bending once it is released from the substrate. The fingers of the microcage quickly close through the shape memory effect once the temperature reaches the austenite transformation point to execute the gripping action. Opening of the microcage is realized by either decreasing the temperature to make use of the martensitic transformation or further increasing the temperature to use the bimorph thermal effect. The biocompatibility of both the TiNi and DLC films has been investigated using a cell-culture method.
The wireless capsule endoscope (WCE) is a new diagnostic tool for searching for the cause of obscure gastrointestinal bleeding. A WCE contains video imaging, self-illumination, image transmission modules and a battery [1, 2]. The indwelling camera takes images and uses wireless radio transmission to send the images to a receiving recorder device that the patient wears around the waist. However, there are two drawbacks for the current WCE: (1) lack of ability for biopsy; and (2) difficulty in identifying the precise location of the pathology. Without tissue diagnosis, it is often difficult to differentiate inflammatory lesions from tumour infiltration.
This article discusses the importance of the choice of synthetic methodology in the purity, and therefore performance, of both small-molecule and polymeric organic semiconductors. We discuss common methodologies used in the preparation of organic semiconductors, paying particular attention to the impurities and by-products that can arise during these synthetic approaches and how they can have an impact on semiconductor performance.
A gastroenteritis outbreak occurred in a military camp where a laboratory and epidemiological investigation was carried out. The early onset of symptoms indicated probable food contamination with Clostridium perfringens. Stool samples collected from affected patients were tested within 4 h via real-time polymerase chain reaction (PCR) for the presence of the C. perfringens plc gene. Ten out of the 12 stool samples were positive. Confirmation of the molecular test results was carried out by enumeration of C. perfringens in stool by culture and shown to be in excess of 106 spores/g stool. The isolates obtained from culture were further analysed by PCR for the presence of the chromosomal enterotoxin (cpe) gene. Based on the clinical symptoms, epidemiological and laboratory investigations, C. perfringens was implicated as the aetiological agent. The ability to conduct real-time PCR analysis greatly shortens the time to diagnosis and allows for preventive and control measures to be effected quickly.