Immunohistochemical detection of IgM and IgG in lung tissue of dogs with leptospiral pulmonary haemorrhage syndrome (LPHS).

Leptospiral pulmonary haemorrhage syndrome (LPHS) is a severe form of leptospirosis. Pathogenic mechanisms are poorly understood. Lung tissues from 26 dogs with LPHS, 5 dogs with pulmonary haemorrhage due to other causes and 6 healthy lungs were labelled for IgG (n=26), IgM (n=25) and leptospiral antigens (n=26). Three general staining patterns for IgG/IgM were observed in lungs of dogs with LPHS with most tissues showing more than one staining pattern: (1) alveolar septal wall staining, (2) staining favouring alveolar surfaces and (3) staining of intra-alveolar fluid. Healthy control lung showed no staining, whereas haemorrhagic lung from dogs not infected with Leptospira showed staining of intra-alveolar fluid and occasionally alveolar septa. Leptospiral antigens were not detected. We conclude that deposition of IgG/IgM is demonstrable in the majority of canine lungs with naturally occurring LPHS, similar to what has been described in other species. Our findings suggest involvement of the host humoral immunity in the pathogenesis of LPHS and provide further evidence to support the dog as a natural disease model for human LPHS.

Immunohistochemical panel for the diagnosis of Hirschsprung's disease using antibodies to MAP2, calretinin, GLUT1 and S100.

AIMS The diagnosis of Hirschsprung's disease is currently based on the identification of aganglionosis and the presence of an increase in acetylcholinesterase-positive hypertrophic nerve fibres in the large bowel submucosa. However, acetylcholinesterase staining is laborious and requires a skilled technician. The aim of this study was to identify a method for diagnosing Hirschsprung's disease reliably using an immunohistochemical panel of recently proposed markers. METHODS AND RESULTS Sixty-nine specimens from 37 patients were evaluated. MAP2 and calretinin antibodies were shown to stain ganglia reliably in the submucosal and myenteric plexuses of normal tissue. By contrast, reduced staining of ganglia was observed in patients with Hirschsprung's disease. Staining for GLUT1 and S100 was used to evaluate the number and thickness of nerve fibres. Gain of GLUT1 and S100 expression was in contrast to the loss of calretinin and MAP2. Hypertrophic submucosal nerve fibres in Hirschsprung's disease develop a perineurium with a ring-like GLUT1 staining pattern similar in size and intensity to that observed in deeper subserosal tissue. CONCLUSIONS The diagnosis of Hirschsprung's disease using immunohistochemical panels could be as accurate as with conventional frozen section techniques. In particular, the use of a combination of markers for ganglia and hypertrophic nerve fibres highlighting a prominent perineurium in Hirschsprung's disease could be an alternative method.

Localization of Hidden Insulinomas with 68Ga-DOTA-Exendin-4 PET/CT: A Pilot Study.

UNLABELLED (111)In-DOTA-exendin-4 SPECT/CT has been shown to be highly efficient in the detection of insulinomas. We aimed at determining whether novel PET/CT imaging with [Nle(14),Lys(40)(Ahx-DOTA-(68)Ga)NH2]exendin-4 ((68)Ga-DOTA-exendin-4) is feasible and sensitive in detecting benign insulinomas. METHODS (68)Ga-DOTA-exendin-4 PET/CT and (111)In-DOTA-exendin-4 SPECT/CT were performed in a randomized cross-over order on 5 patients with endogenous hyperinsulinemic hypoglycemia. The gold standard for comparison was the histologic diagnosis after surgery. RESULTS In 4 patients histologic diagnosis confirmed a benign insulinoma, whereas one patient refused surgery despite a positive (68)Ga-DOTA-exendin-4 PET/CT scan. In 4 of 5 patients, previously performed conventional imaging (CT or MR imaging) was not able to localize the insulinoma. (68)Ga-DOTA-exendin-4 PET/CT correctly identified the insulinoma in 4 of 4 patients, whereas (111)In-DOTA-exendin-4 SPECT/CT correctly identified the insulinoma in only 2 of 4 patients. CONCLUSION These preliminary data suggest that the use of (68)Ga-DOTA-exendin-4 PET/CT in detecting hidden insulinomas is feasible.

Real-Time Localization Using Software Defined Radio

Service providers make use of cost-effective wireless solutions to identify, localize, and possibly track users using their carried MDs to support added services, such as geo-advertisement, security, and management. Indoor and outdoor hotspot areas play a significant role for such services. However, GPS does not work in many of these areas. To solve this problem, service providers leverage available indoor radio technologies, such as WiFi, GSM, and LTE, to identify and localize users. We focus our research on passive services provided by third parties, which are responsible for (i) data acquisition and (ii) processing, and network-based services, where (i) and (ii) are done inside the serving network. For better understanding of parameters that affect indoor localization, we investigate several factors that affect indoor signal propagation for both Bluetooth and WiFi technologies. For GSM-based passive services, we developed first a data acquisition module: a GSM receiver that can overhear GSM uplink messages transmitted by MDs while being invisible. A set of optimizations were made for the receiver components to support wideband capturing of the GSM spectrum while operating in real-time. Processing the wide-spectrum of the GSM is possible using a proposed distributed processing approach over an IP network. Then, to overcome the lack of information about tracked devices’ radio settings, we developed two novel localization algorithms that rely on proximity-based solutions to estimate in real environments devices’ locations. Given the challenging indoor environment on radio signals, such as NLOS reception and multipath propagation, we developed an original algorithm to detect and remove contaminated radio signals before being fed to the localization algorithm. To improve the localization algorithm, we extended our work with a hybrid based approach that uses both WiFi and GSM interfaces to localize users. For network-based services, we used a software implementation of a LTE base station to develop our algorithms, which characterize the indoor environment before applying the localization algorithm. Experiments were conducted without any special hardware, any prior knowledge of the indoor layout or any offline calibration of the system.

Real-time localization using software defined radio

Service providers make use of cost-effective wireless solutions to identify, localize, and possibly track users using their carried MDs to support added services, such as geo-advertisement, security, and management. Indoor and outdoor hotspot areas play a significant role for such services. However, GPS does not work in many of these areas. To solve this problem, service providers leverage available indoor radio technologies, such as WiFi, GSM, and LTE, to identify and localize users. We focus our research on passive services provided by third parties, which are responsible for (i) data acquisition and (ii) processing, and network-based services, where (i) and (ii) are done inside the serving network. For better understanding of parameters that affect indoor localization, we investigate several factors that affect indoor signal propagation for both Bluetooth and WiFi technologies. For GSM-based passive services, we developed first a data acquisition module: a GSM receiver that can overhear GSM uplink messages transmitted by MDs while being invisible. A set of optimizations were made for the receiver components to support wideband capturing of the GSM spectrum while operating in real-time. Processing the wide-spectrum of the GSM is possible using a proposed distributed processing approach over an IP network. Then, to overcome the lack of information about tracked devices’ radio settings, we developed two novel localization algorithms that rely on proximity-based solutions to estimate in real environments devices’ locations. Given the challenging indoor environment on radio signals, such as NLOS reception and multipath propagation, we developed an original algorithm to detect and remove contaminated radio signals before being fed to the localization algorithm. To improve the localization algorithm, we extended our work with a hybrid based approach that uses both WiFi and GSM interfaces to localize users. For network-based services, we used a software implementation of a LTE base station to develop our algorithms, which characterize the indoor environment before applying the localization algorithm. Experiments were conducted without any special hardware, any prior knowledge of the indoor layout or any offline calibration of the system.

Clinical Significance of NOTCH1 and NOTCH2 Expression in Gastric Carcinomas: An Immunohistochemical Study.

BACKGROUND NOTCH signaling can exert oncogenic or tumor suppressive functions and can contribute to chemotherapy resistance in cancer. In this study, we aimed to clarify the clinicopathological significance and the prognostic and predictive value of NOTCH1 and NOTCH2 expression in gastric cancer (GC). METHODS NOTCH1 and NOTCH2 expression was determined immunohistochemically in 142 primarily resected GCs using tissue microarrays and in 84 pretherapeutic biopsies from patients treated by neoadjuvant chemotherapy. The results were correlated with survival, response to therapy, and clinico-pathological features. RESULTS Primarily resected patients with NOTCH1-negative tumors demonstrated worse survival. High NOTCH1 expression was associated with early-stage tumors and with significantly increased survival in this subgroup. Higher NOTCH2 expression was associated with early-stage and intestinal-type tumors and with better survival in the subgroup of intestinal-type tumors. In pretherapeutic biopsies, higher NOTCH1 and NOTCH2 expression was more frequent in non-responding patients, but these differences were statistically not significant. CONCLUSION Our findings suggested that, in particular, NOTCH1 expression indicated good prognosis in GC. The close relationship of high NOTCH1 and NOTCH2 expression with early tumor stages may indicate a tumor-suppressive role of NOTCH signaling in GC. The role of NOTCH1 and NOTCH2 in neoadjuvantly treated GC is limited.

Robust indoor localization of narrowband signals

Many location-based services target users in indoor environments. Similar to the case of dense urban areas where many obstacles exist, indoor localization techniques suffer from outlying measurements caused by severe multipath propaga??tion and non-line-of-sight (NLOS) reception. Obstructions in the signal path caused by static or mobile objects downgrade localization accuracy. We use robust multipath mitigation techniques to detect and filter out outlying measurements in indoor environments. We validate our approach using a power-based lo??calization system with GSM. We conducted experiments without any prior knowledge of the tracked device's radio settings or the indoor radio environment. We obtained localization errors in the range of 3m even if the sensors had NLOS links to the target device.

Solvation-Driven Charge Transfer and Localization in Metal Complexes

In any physicochemical process in liquids, the dynamical response of the solvent to the solutes out of equilibrium plays a crucial role in the rates and products: the solvent molecules react to the changes in volume and electron density of the solutes to minimize the free energy of the solution, thus modulating the activation barriers and stabilizing (or destabilizing) intermediate states. In charge transfer (CT) processes in polar solvents, the response of the solvent always assists the formation of charge separation states by stabilizing the energy of the localized charges. A deep understanding of the solvation mechanisms and time scales is therefore essential for a correct description of any photochemical process in dense phase and for designing molecular devices based on photosensitizers with CT excited states. In the last two decades, with the advent of ultrafast time-resolved spectroscopies, microscopic models describing the relevant case of polar solvation (where both the solvent and the solute molecules have a permanent electric dipole and the mutual interaction is mainly dipole−dipole) have dramatically progressed. Regardless of the details of each model, they all assume that the effect of the electrostatic fields of the solvent molecules on the internal electronic dynamics of the solute are perturbative and that the solvent−solute coupling is mainly an electrostatic interaction between the constant permanent dipoles of the solute and the solvent molecules. This well-established picture has proven to quantitatively rationalize spectroscopic effects of environmental and electric dynamics (time-resolved Stokes shifts, inhomogeneous broadening, etc.). However, recent computational and experimental studies, including ours, have shown that further improvement is required. Indeed, in the last years we investigated several molecular complexes exhibiting photoexcited CT states, and we found that the current description of the formation and stabilization of CT states in an important group of molecules such as transition metal complexes is inaccurate. In particular, we proved that the solvent molecules are not just spectators of intramolecular electron density redistribution but significantly modulate it. Our results solicit further development of quantum mechanics computational methods to treat the solute and (at least) the closest solvent molecules including the nonperturbative treatment of the effects of local electrostatics and direct solvent−solute interactions to describe the dynamical changes of the solute excited states during the solvent response.

Expression and distribution of a vacuolar aquaporin in young and mature leaf tissues of Brassica napus in relation to water fluxes

Recently, it has been shown that water fluxes across biological membranes occur not only through the lipid bilayer but also through specialized water-conducting proteins, the so called aquaporins. In the present study, we investigated in young and mature leaves of Brassica napus L. the expression and localization of a vacuolar aquaporin homologous to radish γ-tonoplast intrinsic protein/vacuolar-membrane integral protein of 23 kDa (TIP/VM 23). In-situ hybridization showed that these tonoplast aquaporins are highly expressed not only in developing but also in mature leaves, which export photosynthates. No substantial differences could be observed between different tissues of young and mature leaves. However, independent of the developmental stage, an immunohistochemical approach revealed that the vacuolar membrane of bundle-sheath cells contained more protein cross-reacting with antibodies raised against radish γ-TIP/VM 23 than the mesophyll cells. The lowest labeling was detected in phloem cells. We compared these results with the distribution of plasma-membrane aquaporins cross-reacting with antibodies detecting a domain conserved among members of the plasma-membrane intrinsic protein 1 (PIP1) subfamily. We observed the same picture as for the vacuolar aquaporins. Furthermore, a high density of gold particles labeling proteins of the PIP1 group could be observed in plasmalemmasomes of the vascular parenchyma. Our results indicate that γ-TIP/VM 23 and PIP1 homologous proteins show a similar expression pattern. Based on these results it is tempting to speculate that bundle-sheath cells play an important role in facilitating water fluxes between the apoplastic and symplastic compartments in close proximity to the vascular tissue.

Growth Cone Localization of the mRNA Encoding the Chromatin Regulator HMGN5 Modulates Neurite Outgrowth

Neurons exploit local mRNA translation and retrograde transport of transcription factors to regulate gene expression in response to signaling events at distal neuronal ends. Whether epigenetic factors could also be involved in such regulation is not known. We report that the mRNA encoding the high-mobility group N5 (HMGN5) chromatin binding protein localizes to growth cones of both neuron-like cells and of hippocampal neurons, where it has the potential to be translated, and that HMGN5 can be retrogradely transported into the nucleus along neurites. Loss of HMGN5 function induces transcriptional changes and impairs neurite outgrowth, while HMGN5 overexpression induces neurite outgrowth and chromatin decompaction; these effects are dependent on growth cone localization of Hmgn5 mRNA. We suggest that the localization and local translation of transcripts coding for epigenetic factors couple the dynamic neuronal outgrowth process with chromatin regulation in the nucleus.