Forensic and clinical diagnosis in shaken baby syndrome , between child abuse and iatrogenic abuse

“Shaken baby syndrome” in child abuse cases is a challenge for pediatrician and forensic experts, often a diagnosis of exclusion, with overwhelming moral and legal implications. Diagnosis is based on: subdural bleeding, rupture of retinal vessels, traumatic diffuse axonal injury with diffuse brain encephalopathy in the absence of external traumatic injuries and anamnesis data of an accidentally head injury. Microscopic findings in diffuse axonal injuries were initially considered as a specific traumatic effect due to unrestricted movement and accelerated rotation of the head. Immunohistochemistry of beta amyloid protein precursor is gold standard method for identifying pathological diffuse axonal lesions, which is however non-specific in brain trauma. In the diagnosis of this syndrome pediatricians and forensic examiners must take into account the particularities of each case, avoiding scientific speculation, to intuit controversies and always be familiar with the differential diagnosis

Quasi-Cyclic Asymptotically Regular LDPC Codes

Families of "asymptotically regular" LDPC block code ensembles can be formed by terminating (J,K)-regular protograph-based LDPC convolutional codes. By varying the termination length, we obtain a large selection of LDPC block code ensembles with varying code rates, minimum distance that grows linearly with block length, and capacity approaching iterative decoding thresholds, despite the fact that the terminated ensembles are almost regular. In this paper, we investigate the properties of the quasi-cyclic (QC) members of such an ensemble. We show that an upper bound on the minimum Hamming distance of members of the QC sub-ensemble can be improved by careful choice of the component protographs used in the code construction. Further, we show that the upper bound on the minimum distance can be improved by using arrays of circulants in a graph cover of the protograph.Comment: To be presented at the 2010 IEEE Information Theory Workshop, Dublin, Irelan

Computational Modeling of Channelrhodopsin-2 Photocurrent Characteristics in Relation to Neural Signaling

Channelrhodopsins-2 (ChR2) are a class of light sensitive proteins that offer the ability to use light stimulation to regulate neural activity with millisecond precision. In order to address the limitations in the efficacy of the wild-type ChR2 (ChRwt) to achieve this objective, new variants of ChR2 that exhibit fast mono-exponential photocurrent decay characteristics have been recently developed and validated. In this paper, we investigate whether the framework of transition rate model with 4 states, primarily developed to mimic the bi-exponential photocurrent decay kinetics of ChRwt, as opposed to the low complexity 3 state model, is warranted to mimic the mono-exponential photocurrent decay kinetics of the newly developed fast ChR2 variants: ChETA (Gunaydin et al., Nature Neurosci, 13:387-392, 2010) and ChRET/TC (Berndt et al., PNAS, 108:7595-7600, 2011). We begin by estimating the parameters for the 3-state and 4-state models from experimental data on the photocurrent kinetics of ChRwt, ChETA and ChRET/TC. We then incorporate these models into a fast-spiking interneuron model (Wang and Buzsaki., J Neurosci, 16:6402-6413,1996) and a hippocampal pyramidal cell model (Golomb et al., J Neurophysiol, 96:1912-1926, 2006) and investigate the extent to which the experimentally observed neural response to various optostimulation protocols can be captured by these models. We demonstrate that for all ChR2 variants investigated, the 4 state model implementation is better able to capture neural response consistent with experiments across wide range of optostimulation protocol. We conclude by analytically investigating the conditions under which the characteristic specific to the 3-state model, namely the mono-exponential photocurrent decay of the newly developed variants of ChR2, can occurs in the framework of the 4-state model.Comment: 10 figure

Engineered antibody and neuropeptide mediated radionuclide targeting in prostate cancer

PhDProstate cancer (PC) is the most common cancer type in men in the western world and to date no definitive stratergy to image PC is avaliable. This thesis explores the possibility of using Prostate Specific Membrane Antigen (PSMA) and Gastrin Releasing Peptide Receptor (GRP-R) as biomarkers for the targeting and imaging of PC. The development of an imaging radiopharmaceutical to image all stages of PC growth would improve diagnosis, staging and personalised treatment, as present imaging modalities for PC rely largely on anatomical changes to allow visualisation and have limited sensitivity for imaging metastatic spread of the disease. PSMA was selected due to its up-regulation in advanced carcinoma and metastatic disease and GRP-R due to its high levels of expression in the early stages of PC. The hypothesis is that PC can be imaged by a suitably designed radioligand directed against an appropriate molecular target, such as PSMA and GRP-R. Both of these targets were believed to be appropriate as both are present preferntially in prostate tissue and they both internalise when bound by their ligand. To target PSMA, phage libraries were screened for scFv against both cell-expressed PSMA and recombinant PSMA and diabodies were also generated from high binding clones. Several promising candidates were produced which selectively bound to LNCaP cells and PSMA protein in both FACS and ELISA. Diabodies showed improved binding over corresponding scFv’s. In vivo analysis of tumour-bearing mice failed to reveal tumour uptake of either the scFv or the diabody. In vitro analysis suggested that the affinity of the antibody fragments were not sufficiently high. [99mTc]-Demobesin 4 (DB 4), a radiolabelled GRP-R binding peptide was synthesised. Radioligand binding assays performed on a range of androgen-independent and androgen-dependent PC cell lines showed high GRP-R expression in the androgen dependent LNCaP line but also in the androgen-independent cell lines PC3 and DU145. GRP-R expression, measured by RT-PCR to determine the amount of GRP-R RNA, was similar to that seen using radioligand binding assays and similar patterns were observed in autoradiographic studies. In vivo studies on mice bearing the PC xenografts showed tumour uptake and localisation of [99mTc]-DB 4 within one hour. A limited correlation was observed between results obtained in vivo and in vitro. In conclusion, the results were partly consistant with the hypothesis, whereby initial aims for the PSMA project were successfully achieved with generation of scFv and diabodies that specifically bound, however they proved unsuitable as potential imaging agents, perhaps owing to low binding affinity. GRP-R was shown to be an effective candidate for radioimmaging PC which has the potential to descrininate [99mTc]-DB4 uptake between androgen-independent/dependent cells. Thus this radiopharmaceutical may prove a useful imaging agent for early prostate cancer but that further studies are required to assess its usefulness in the androgen-independent stages of the disease

“The Road Not Taken” – Israeli Teachers’ Reactions to Top-Down Educational Reform

The authors have investigated teachers’ reactions towards an imposed reform initiated by the Israeli Ministry of Education in collaboration with one of two teachers’ unions based on the messages and letters sent by high school teachers to an internet forum during a teachers’ strike which took place between October and December of 2007. This study is the result of collaborative work between a teacher educator and a veteran teacher studying towards her Master of Education degree in Learning and Instruction. The research question was: What were the teachers’ attitudes regarding the “New Horizon” reform as conveyed on an internet forum during the strike? The article focuses on the teachers’ opposition to the proposed reform. The authors explore the use of the internet for sustaining this strike while also discussing the methodological issues related to this type of analysis and relation to collaborative research. Recommendations are suggested for successful implementation of educational reforms

The role of reactive astrocitose in the chronological evolution of traumatic brain injury

Introduction and objectives. This study aims to investigate whether the cerebral modifications of posttraumatic reactive astrocitose can be considered an objective criterion for determining the age of traumatic cranio-cerebral lesions. Materials and methods. The present study consists of a series of 23 medico-legal cases that underwent autopsy inTeleormanCounty(Romania) Department of Forensic Medicine during 2007–2016, with full immune-histochemical microscopic examination using GFAP staining. The study consists of two groups, a series of 13 cases with cranio-cerebral trauma with different posttraumatic survival periods and 9 cases as a control group. Results and discussions. We discovered GFAP+ reactive astrocytes even when death occurred immediately after the trauma event and up to 4 months after the traumatic incident. We also discovered an intense positive correlation between the density of the GFAP+ cell from the perilesional area and the posttraumatic survival period. The highest cerebral density of the GFAP+ astrocytes occurred with acute death prior (1 to 24 hours) and the lowest in the chronic period (over 2 weeks). Conclusions. The gradual and differentiated appearance of the reactive astrocytes in close relation with the cerebral posttraumatic interval, with specific lesional and perilesional distribution as well as in surrounding area, clearly demonstrates that the state of the reactive astrocitose may constitute an objective index for evaluation of the elapsed time after the posttraumatic event

Mineral profile grassland of Andropogon lateralis and Sorghastrum setosum (Gramineae) in Corrientes, Argentina

El objetivo de este trabajo fue determinar la composición florística y el aporte de minerales a la dieta animal para la producción de carne bovina de los pastizales de Andropogon lateralis Nees (PAL) y Sorghastrum setosun (Griseb.) Hitchc. (PSS), analizados mediante espectrometría ICP-AES en dos series de suelo de la provincia de Corrientes, Argentina. El mayor aporte de materia seca lo realizan A. lateralis y S. setosum. El aporte de leguminosas es bajo. El perfil de elementos minerales esenciales, probablemente esenciales y los de función incierta, cubren parcialmente los requerimientos del ganado bovino productor de carne, excepto para Mn. Las relaciones entre elementos, Ca/P, Na/K (mEq), Cu/Mo y Cu/Fe son aceptables. Las relaciones K/Mg, K/Ca+Mg (mEq) y Na/Mg (mEq) no son adecuadas, pues existe deficiencia de Mg.The goal of this work was to determine the floristic composition and the mineral contribution of Andropogon lateralis Nees (PAL) and Sorghastrum setosum (PSS) pastures, in the animal diet for the production of beef, analyzed by ICP-AES spectrometry in two series of soils from the Province of Corrientes, Argentina. The greatest contribution of dry raw matter is provided by A. lateralis and S. setosum. The contribution of legume is low. The profile of essential mineral elements, probably essential ones and of those of uncertain function, partially fulfill the meat producer cattle requirements. The elemental ratios Ca/P, Na/K (mEq), Cu/Mo and Cu/Fe, are acceptable. The K/Mg, K/Ca+Mg (mEq) and Na/Mg (mEq) ratios are not adequate, and there is Mg deficiency.Fil: Bernardis, Aldo C.. Universidad Nacional del Nordeste. Facultad de Ciencias AgrariasFil: Villafañe, Roxana. Consejo Nacional de Investigaciones Científicas y TécnicasFil: Pellerano, Roberto G.. Universidad Nacional del NordesteFil: Marchevky, Eduardo. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Química