The underpotential deposition that should not be : Cu(1x1) on Au(111)

Peer reviewedPostprin

Development of functional ectopic compound eyes in scarabaeid beetles by knockdown of orthodenticle

Complex traits like limbs, brains, or eyes form through coordinated integration of diverse cell fates across developmental space and time, yet understanding how complexity and integration emerge from uniform, undifferentiated precursor tissues remains limited. Here, we use ectopic eye formation as a paradigm to investigate the emergence and integration of novel complex structures following massive ontogenetic perturbation. We show that down-regulation via RNAi of a single head patterning gene—orthodenticle—induces ectopic structures externally resembling compound eyes at the middorsal adult head of both basal and derived scarabaeid beetle species (Onthophagini and Oniticellini). Scanning electron microscopy documents ommatidial organization of these induced structures, while immunohistochemistry reveals the presence of rudimentary ommatidial lenses, crystalline cones, and associated neural-like tissue within them. Further, RNA-sequencing experiments show that after orthodenticle down-regulation, the transcriptional signature of the middorsal head—the location of ectopic eye induction—converges onto that of regular compound eyes, including up-regulation of several retina-specific genes. Finally, a light-aversion behavioral assay to assess functionality reveals that ectopic compound eyes can rescue the ability to respond to visual stimuli when wild-type eyes are surgically removed. Combined, our results show that knockdown of a single gene is sufficient for the middorsal head to acquire the competence to ectopically generate a functional compound eye-like structure. These findings highlight the buffering capacity of developmental systems, allowing massive genetic perturbations to be channeled toward orderly and functional developmental outcomes, and render ectopic eye formation a widely accessible paradigm to study the evolution of complex systems.Fil: Zattara, Eduardo Enrique. Indiana University; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Macagno, Anna L. M.. Indiana University; Estados UnidosFil: Busey, Hannah A.. Indiana University; Estados UnidosFil: Moczek, Armin P.. Indiana University; Estados Unido

The weight of water

Leonardo da Vinci’s pioneering work on hydrostatics combined traditional knowledge and innovative empiricism in an attempt to understand an object fraught with paradox: the water-filled container

Kinetics and mechanisms of electrochemical reactions on platinum with solutions of iodine-sodium iodide in acetonitrile

The kinetics of the iodine-tri-iodide-iodide electrode in acetonitrile has been investigated in the temperature range from 0 to 30°C. Current/voltage curves were determined using a platinum rotating disk electrode working at 200 to 3000 rpm. The anodic and cathodic current/voltage curves are characterized by two well defined waves. The total reactions related to the first and second anodic waves are respectively 3I− = I3− + 2 e and 2I3− = 3I2 + 2 e, while the reverse reactions represent the second and first cathodic waves respectively. The diffusion coefficients of the diffusing species have been evaluated. Current/voltage curves in the region preceding the limiting cd exhibit a measurable irreversibility. The kinetic parameters related to the activated process were determined, and the kinetics of the reactions interpreted in terms of reaction mechanisms that involve an ion plus atom reaction as rate determining step for the anodic process and the reverse reaction for the cathodic process.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA)Facultad de Ciencias Exacta

Kinetics and mechanisms of electrochemical reactions on platinum with solutions of iodine-sodium iodide in acetonitrile

The kinetics of the iodine-tri-iodide-iodide electrode in acetonitrile has been investigated in the temperature range from 0 to 30°C. Current/voltage curves were determined using a platinum rotating disk electrode working at 200 to 3000 rpm. The anodic and cathodic current/voltage curves are characterized by two well defined waves. The total reactions related to the first and second anodic waves are respectively 3I− = I3− + 2 e and 2I3− = 3I2 + 2 e, while the reverse reactions represent the second and first cathodic waves respectively. The diffusion coefficients of the diffusing species have been evaluated. Current/voltage curves in the region preceding the limiting cd exhibit a measurable irreversibility. The kinetic parameters related to the activated process were determined, and the kinetics of the reactions interpreted in terms of reaction mechanisms that involve an ion plus atom reaction as rate determining step for the anodic process and the reverse reaction for the cathodic process.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA)Facultad de Ciencias Exacta

Dialogical functions of metaphors in medical interactions

This paper proposes a method for analyzing the dialogical functions of metaphors in communicative interactions, and more specifically in the context of medical interviews. The dialogical goals proposed and pursued by the interlocutors are coded using a coding scheme that captures seven mutually exclusive categories of dialogical moves. The functions of the moves, including metaphors, can be identified and correlated with other variables relevant to the type of communication under analysis. The coding scheme is used to analyze a corpus of 39 interactions between healthcare providers and patients affected by Type 2 diabetes. The exploratory quantitative analysis, for the purpose of determining the different distributions of metaphor uses between patients and providers, is combined with qualitative analysis in which the thematic areas of the metaphors are considered. The findings show how patients and providers use metaphors for pursuing different dialogical goals and meeting distinct communicative needs

Adaptive maternal behavioral plasticity and developmental programming mitigate the transgenerational effects of temperature in dung beetles

Phenotypic plasticity allows organisms to cope with rapid environmental change. Yet exactly when during ontogeny plastic responses are elicited, whether plastic responses produced in one generation influence phenotypic variation and fitness in subsequent generations, and the role of plasticity in shaping population divergences, remains overall poorly understood. Here, we use the dung beetle Onthophagus taurus to assess plastic responses to temperature at several life stages bridging three generations and compare these responses across three recently diverged populations. We find that beetles reared at hotter temperatures grow less than those reared at mild temperatures, and that this attenuated growth has transgenerational consequences by reducing offspring size and survival in subsequent generations. However, we also find evidence that plasticity may mitigate these consequences in two ways: 1) mothers modify the temperature of their offspring's developmental environment via behavioral plasticity and 2) in one population, offspring exhibit accelerated growth when exposed to hot temperatures during very early development (‘developmental programming’). Lastly, our study reveals that offspring responses to temperature diverged among populations in fewer than 100 generations, possibly in response to range-specific changes in climatic or social conditions.Fil: Macagno, Anna L. M.. Indiana University; Estados UnidosFil: Zattara, Eduardo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Indiana University; Estados UnidosFil: Ezeakudo, Onye. Homestead High School; Estados UnidosFil: Moczek, Armin P.. Indiana University; Estados UnidosFil: Ledón Rettig, Cristina. Indiana University; Estados Unido

Duplications of KIAA1549 and BRAF screening by Droplet Digital PCR from formalin-fixed paraffin-embedded DNA is an accurate alternative for KIAA1549-BRAF fusion detection in pilocytic astrocytomas

Pilocytic astrocytomas represent the most common glioma subtype in young patients and account for 5.4% of all gliomas. They are characterized by alterations in the RAS–MAP kinase pathway, the most frequent being a tandem duplication on chromosome 7q34 involving the BRAF gene, resulting in oncogenic BRAF fusion proteins. BRAF fusion involving the KIAA1549 gene is a hallmark of pilocytic astrocytoma, but it has also been recorded in rare cases of gangliogliomas, 1p/19q co-deleted oligodendroglial tumors, and it is also a common feature of disseminated oligodendroglial-like leptomeningeal neoplasm. In some difficult cases, evidence for KIAA1549-BRAF fusion is of utmost importance for the diagnosis. Moreover, because the KIAA1549-BRAF fusion constitutively activates the MAP kinase pathway, it represents a target for drugs such as MEK inhibitors, and therefore, the detection of this genetic abnormality is highly relevant in the context of clinical trials applying such new approaches. In the present study, we aimed to use the high sensitivity of Droplet Digital PCR (DDPCR™) to predict KIAA1549-BRAF fusion on very small amounts of formalin-fixed paraffin-embedded tissue in routine practice. Therefore, we analyzed a training cohort of 55 pilocytic astrocytomas in which the KIAA1549-BRAF fusion status was known by RNA sequencing used as our gold standard technique. Then, we analyzed a prospective cohort of 40 pilocytic astrocytomas, 27 neuroepithelial tumors remaining difficult to classify (pilocytic astrocytoma versus ganglioglioma or diffuse glioma), 15 dysembryoplastic neuroepithelial tumors, and 18 gangliogliomas. We could demonstrate the usefulness and high accuracy (100% sensitivity and specificity when compared to RNA sequencing) of DDPCR™ to assess the KIAA1549-BRAF fusion from very low amounts of DNA isolated from formalin-fixed paraffin-embedded specimens. BRAF duplication is both necessary and sufficient to predict this fusion in most cases and we propose that this single analysis could be used in routine practice to save time, money, and precious tissue

DNA vaccines against ErbB2+ Carcinomas: From mice to humans.

DNA vaccination exploits a relatively simple and flexible technique to generate an immune response against microbial and tumor-associated antigens (TAAs). Its effectiveness is enhanced by the application of an electrical shock in the area of plasmid injection (electroporation). In our studies we exploited a sophisticated electroporation device approved for clinical use (Cliniporator, IGEA, Carpi, Italy). As the target antigen is an additional factor that dramatically modulates the efficacy of a vaccine, we selected ErbB2 receptor as a target since it is an ideal oncoantigen. It is overexpressed on the cell membrane by several carcinomas for which it plays an essential role in driving their progression. Most oncoantigens are self-tolerated molecules. To circumvent immune tolerance we generated two plasmids (RHuT and HuRT) coding for chimeric rat/human ErbB2 proteins. Their immunogenicity was compared in wild type mice naturally tolerant for mouse ErbB2, and in transgenic mice that are also tolerant for rat or human ErbB2. In several of these mice, RHuT and HuRT elicited a stronger anti-tumor response than plasmids coding for fully human or fully rat ErbB2. The ability of heterologous moiety to blunt immune tolerance could be exploited to elicit a significant immune response in patients. A clinical trial to delay the recurrence of ErbB2+ carcinomas of the oral cavity, oropharynx and hypopharynx is awaiting the approval of the Italian authorities

Kinetics and mechanisms of electrochemical reactions on platinum with solutions of iodine-sodium iodide in acetonitrile

The kinetics of the iodine-tri-iodide-iodide electrode in acetonitrile has been investigated in the temperature range from 0 to 30°C. Current/voltage curves were determined using a platinum rotating disk electrode working at 200 to 3000 rpm. The anodic and cathodic current/voltage curves are characterized by two well defined waves. The total reactions related to the first and second anodic waves are respectively 3I− = I3− + 2 e and 2I3− = 3I2 + 2 e, while the reverse reactions represent the second and first cathodic waves respectively. The diffusion coefficients of the diffusing species have been evaluated. Current/voltage curves in the region preceding the limiting cd exhibit a measurable irreversibility. The kinetic parameters related to the activated process were determined, and the kinetics of the reactions interpreted in terms of reaction mechanisms that involve an ion plus atom reaction as rate determining step for the anodic process and the reverse reaction for the cathodic process.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA)Facultad de Ciencias Exacta