Peroxisomal proliferator activated receptor-γ deficiency in a Canadian kindred with familial partial lipodystrophy type 3 (FPLD3)

BACKGROUND: Familial partial lipodystrophy (Dunnigan) type 3 (FPLD3, Mendelian Inheritance in Man [MIM] 604367) results from heterozygous mutations in PPARG encoding peroxisomal proliferator-activated receptor-γ. Both dominant-negative and haploinsufficiency mechanisms have been suggested for this condition. METHODS: We present a Canadian FPLD3 kindred with an affected mother who had loss of fat on arms and legs, but no increase in facial, neck, suprascapular or abdominal fat. She had profound insulin resistance, diabetes, severe hypertriglyceridemia and relapsing pancreatitis, while her pre-pubescent daughter had normal fat distribution but elevated plasma triglycerides and C-peptide and depressed high-density lipoprotein cholesterol. RESULTS: The mother and daughter were each heterozygous for PPARG nonsense mutation Y355X, whose protein product in vitro was transcriptionally inactive with no dominant-negative activity against the wild-type receptor. In addition the mutant protein appeared to be markedly unstable. CONCLUSION: Taken together with previous studies of human PPARG mutations, these findings suggest that PPAR-γ deficiency due either to haploinsufficiency or to substantial activity loss due to dominant negative interference of the normal allele product's function can each contribute to the FPLD3 phenotype

A stringent yeast two-hybrid matrix screening approach for protein-protein interaction discovery

The yeast two-hybrid (Y2H) system is currently one of the most important techniques for protein-protein interaction (PPI) discovery. Here, we describe a stringent three-step Y2H matrix interaction approach that is suitable for systematic PPI screening on a proteome scale. We start with the identification and elimination of autoactivating strains that would lead to false-positive signals and prevent the identification of interactions. Nonautoactivating strains are used for the primary PPI screen that is carried out in quadruplicate with arrayed preys. Interacting pairs of baits and preys are identified in a pairwise retest step. Only PPI pairs that pass the retest step are regarded as potentially biologically relevant interactions and are considered for further analysis

Effect of drilling and wellbore geometry parameters on wellbore temperature profile: Implications for geothermal production

Prediction of the wellbore fluids and formation temperatures is crucial during drilling operation, especially for high temperature wells, such as geothermal applications. This work presents the applications of an improved comprehensive drilling simulator for predicting the wellbore system temperature during the drilling process. A fully transient numerical model of the wellbore temperature is developed for drilling and geothermal production applications. The model describes the dynamic behaviour of the thermal state of the wellbore during circulation and static conditions. The developed model is implemented with the commercial virtual drilling simulator through an application programming interface. This implementation allows the coupling of the thermal model with other physical models, which leads to more advanced and realistic simulations. The model has been previously validated through a direct comparison with field data from geothermal well located in the Hanover area in Germany. The results showed a good agreement between the predicted outlet fluid temperature and the measured one. Furthermore, an analysis of the effect of various parameters on the wellbore system temperature is performed. This analysis showed the impact of these parameters on the wellbore temperature profile including the critical areas such as the casing setting point and bottom hole assembly. This information may lead to enhancing the wellbore stability by monitoring the thermal stresses, especially in high-temperature wells. Moreover, predicting the drill bit temperature can result in increasing the lifetime of the bit by adjusting the operating conditions to keep the bit temperature within the specified range. Based on these results, the enhanced drilling simulator with the transient temperature model showed to be a suitable tool for effective well planning.Document Type: Original articleCited as: Abdelhafiz, M. M., Oppelt, J., Mahmoud, O., Hegele, L. A. Effect of drilling and wellbore geometry parameters on wellbore temperature profile: Implications for geothermal production. Advances in Geo-Energy Research, 2023, 8(3): 170-180. https://doi.org/10.46690/ager.2023.06.0

Task Integration Facilitates Multitasking

The aim of this study was to investigate multi-task integration in a continuous tracking task. We were particularly interested in how manipulating task structure in a dual-task situation affects learning of a constant segment embedded in a pursuit-tracking task. Importantly, we examined if dual-task effects could be attributed to task integration by varying the structural similarity and difficulty of the primary and secondary tasks. In Experiment 1 participants performed a pursuit tracking task while counting high-pitched tones and ignoring low-pitched tones. The tones were either presented randomly or structurally 250 ms before each tracking turn. Experiment 2 increased the motor load of the secondary tasks by asking participants to tap their feet to the tones. Experiment 3 further increased motor load of the primary task by increasing its speed and having participants tracking with their non-dominant hand. The results show that dual-task interference can be moderated by secondary task conditions that match the structure of the primary task. Therefore our results support proposals of task integration in continuous tracking paradigms. We conclude that multi-tasking is not always detrimental for motor learning but can be facilitated through task-integration

Diabetes Susceptibility in the Canadian Oji-Cree Population Is Moderated by Abnormal mRNA Processing of HNF1A G319S Transcripts

OBJECTIVE—The G319S HNF1A variant is associated with an increased risk of type 2 diabetes in the Canadian Oji-Cree population. We hypothesized that the variant site at the 3′ end of exon 4 might influence splicing and characterized mRNA transcripts to investigate the mutational mechanism underlying this susceptibility to diabetes

Clinical impact of MDR1-expression in testicular germ cell cancer

Aim: The multidrug resistance protein 1 (MDR1, P-gp, p-170) is a membrane glycoprotein that acts as an energy-dependent drug efflux pump. In various malignancies its expression is associated with resistance to diverse cytostatic drugs, and therefore predicts resistance to systemic treatment. The aim of this study was to investigate the prognostic value of MDR1 expression in primary tumor tissue to predict necrosis or viable cancer in residual tumor masses after systemic chemotherapy for advanced testicular germ cell cancer. Materials and Methods: Out of 77 patients, histopathological characteristics of primary testicular cancer specimens and retroperitoneal lymph node dissection (RPLND) samples following chemotherapy were available from 72 and all 77 patients, respectively. Moreover, MDR1 expression was determined by immunohistochemistry in 47 primary tumors and corresponding 73 RPLND sections. Results: After chemotherapy and subsequent RPLND, the examination of residual tumor masses revealed that mature teratoma and active viable tumor were predominantly found in patients with non-seminoma (NSGCT; p = 0.048), especially in those with containing mature teratoma (p = 0.001). Moreover, using univariate analysis the expression of MDR1 in the primary testicular tumor predicted viable tumor/teratoma residues in RPLND sections (p = 0.003). However, in multivariate analysis including the tumors’ histological subtype, MDR1 expression alone failed to reach statistical significance as an independent prognostic marker for residual vital tumor (p ≥ 0.16). Conclusions: With the limited number of patients given, the correlation between MDR1 expression in primary testis cancer and active residual retroperitoneal disease after chemotherapy failed to reach statistical significance as in independent marker. Therefore, up to now routine MDR1 staining of testicular germ cell cancer samples should not be performed in clinical practice. However, as there was a clear trend, a larger number of patients suffering from metastatic non-seminomas should be studied, as MDR1 expression might have significant prognostic value in this particular subgroup of patients.Белок 1 множественной лекарств енной устойчив ости (MDR1, P-gp, p-170) – это мембранный гликопротеин, функционирующий как энергозависимый насос. При разл ичных фо рмах опухолей его экспр е ссия связана с устойчив о стью опухоли к различным цитостатикам, что может быть использовано для выбора типа терапии. Цель работы — исследование прогности- ческой значимости экспрессии MDR1 в ткани пе рвичной опухоли для оценки возмо жности раз вития некроза или сохран е ния живых клеток в остаточной ткани опухоли после применения системной химиотерапии на поздних стадиях герминативных опухолей яичка. Материалы и методы: про анализиро ваны гисто патоло гические характ е ристики пе рвично й те стикулярной опухоли и образцов, полученных при иссечении ретроперитонеальных лимфатических узлов (RPLND) после хими отерапии 72 и 77 бол ьных соотве тственно. Экспр ессию MDR1 определяли иммун огист охимич еским методом в 47 образцах первичн ой опухоли и соответствующих 73 ср RPLND. Результаты: после хими отерапии и последующей RPLNDисследовани е оста- точных опухолевых тканей показало, чтозрелая тератома и жизнеспособные опух олевые клетки выяв ляют преимущественно у больных, у которых не была обнаружена семинома (NSGCT; p = 0,048), особенно у так овых , у которых была тератома (p = 0,001). Более того, д анные одно факторного анализа показали, что экспр е ссия MDR1 в ткани пе рвично й те стику лярной опу- холи может служить прогностич еским факт ором сохран ения живых опух олевых клеток срезах RPLND (p = 0,003). О нак о применение мультифакторного анализа, в том числе с учетом гистологического подтипа опухоли, показало, что экспр е ссия MDR1 не имеет самостоятельной прогностической значимости для выявления живых остаточных опух олевых клеток (p 0,16). Выводы: ввиду небольшо йвыборкибольных не выяв лено статистически значимойкорреляции между экспр ессией MDR1 в первичной опухоли яичка и наличием активных резидуальных очагов поражения в ретроперитонеальном пространстве. В т о же время, учитывая выявленную тенденцию, экспрессию MDR1, в качестве возможного прогностич еского марк ера, имеет смысл исследовать именно у больных с метастатическими опухолями, не являющимися семиномой

Plasma homocyst(e)ine concentration, but not MTHFR genotype, is associated with variation in carotid plaque area

Background and Purpose - Elevated plasma homocyst(e)ine [H(e)] concentration is associated with premature atherosclerosis. A common cause of elevated plasma H(e) concentration is a thermolabile mutation (677T) in the gene encoding methylenetetrahydrofolate reductase (MTHFR). We sought to determine whether plasma H(e) concentration or MTHFR genotype would be more strongly associated with carotid plaque area (CPA), a potential intermediate phenotype of atherosclerosis. Methods - In 307 subjects who were ascertained through a premature atherosclerosis clinic, we measured CPA with 2- dimensional ultrasound and also determined traditional atherosclerosis risk factors, in addition to plasma H(e) concentration and MTHFR genotypes. Results - We found that the frequency of the MTHFR 677T allele was 0.363 in this sample. Mean plasma H(e) concentration was significantly higher in 677T/T homozygotes than in 677T/C heterozygotes and 677C/C homozygotes (17.1±13.7 versus 13.5±6.1 versus 12.6±5.9 μmol/L, respectively, P\u3c0.001). Analysis of variance showed that CPA was significantly associated with age, sex, smoking, diabetes, hypertension, and hyperlipidemia (each P\u3c0.05). When plasma H(e) concentration was included in the model, it was significantly associated with CPA (P\u3c0.05). However, when the MTHFR genotype was included in the model, it was not associated with CPA (P=0.50). Furthermore, there was a significant correlation of CPA with plasma H(e) (r=0.23, P\u3c0.0001). However, the mean CPA did not differ between subjects according to genotype. Conclusions - Thus, plasma H(e), but not MTHFR genotype, is significantly associated with carotid atherosclerosis, suggesting that the biochemical test may be sufficient to identify patients who may be at increased risk of atherosclerosis through this mechanism

Transcriptional Profiling of Endocrine Cerebro-Osteodysplasia Using Microarray and Next-Generation Sequencing

BACKGROUND: Transcriptome profiling of patterns of RNA expression is a powerful approach to identify networks of genes that play a role in disease. To date, most mRNA profiling of tissues has been accomplished using microarrays, but next-generation sequencing can offer a richer and more comprehensive picture. METHODOLOGY/PRINCIPAL FINDINGS: ECO is a rare multi-system developmental disorder caused by a homozygous mutation in ICK encoding intestinal cell kinase. We performed gene expression profiling using both cDNA microarrays and next-generation mRNA sequencing (mRNA-seq) of skin fibroblasts from ECO-affected subjects. We then validated a subset of differentially expressed transcripts identified by each method using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Finally, we used gene ontology (GO) to identify critical pathways and processes that were abnormal according to each technical platform. Methodologically, mRNA-seq identifies a much larger number of differentially expressed genes with much better correlation to qRT-PCR results than the microarray (r² = 0.794 and 0.137, respectively). Biologically, cDNA microarray identified functional pathways focused on anatomical structure and development, while the mRNA-seq platform identified a higher proportion of genes involved in cell division and DNA replication pathways. CONCLUSIONS/SIGNIFICANCE: Transcriptome profiling with mRNA-seq had greater sensitivity, range and accuracy than the microarray. The two platforms generated different but complementary hypotheses for further evaluation