Total perfusion-diffusion mismatch detected using resting-state functional MRI

Total perfusion- diffusion mismatch is a well- recognised phenomenon in patients with acute ischaemic stroke. We describe a case of total perfusion- diffusion mismatch detected using an emerging contrast- agent- free perfusion imaging technique in a young patient with acute cerebellar strok

What is happening to the health of the Croatian population?

AIM: To describe the problems in the interpretation of Croatian mortality data and explore possible reasons for the recorded increase in mortality in the 1990-1999 period, particularly related to different methods of collection and estimation of data on deaths and population. METHODS: Numbers of recorded deaths and population estimates were first obtained from the Croatian Institute for Public Health and examined in detail. The Institute used population estimates supplied by the Croatian Statistics Bureau, which included de jure population data (including all Croatian citizens wherever they live) until 1996 and de facto population data (including only population living in Croatia at least for a year, irrespective of citizenship) since 1996. A different set of population estimates based on de facto estimates since 1992 was obtained from the Croatian Bureau of Statistics. We examined trends in age- and sex-specific death rates from major causes in 1990-1999 period, using the mortality data from the Croatian Institute for Public Health and both sets of population estimates. Lung cancer as a cause of death was examined in more detail, since it is relatively stable over short periods of time. Interviews were undertaken with key informants to identify the reasons for any discrepancies. RESULTS: In Croatia, relatively stable death rates from lung cancer in men ranged from 84/100,000 in 1990 to 79/ 100,000 in 1995. In 1996, a marked discontinuity appeared in the Croatian data, with a 14% increase compared to 1995 (from 79/100,000 to 91/100,000) and a further increase in 1999 (94/100,000), which is not credible on the basis of the natural history of lung cancer. Analysis of mortality rates with de facto population estimates showed more gradual increase from 1992-1996. Methods used to estimate population and mortality during the 1990s were inconsistent and misleading. At present, it is impossible to be certain about the true level of mortality in Croatia during 1990s, as the numerator (deaths) and denominator (population) were incompatible until 1998. CONCLUSION: Major problems in data collection would have been identified if the investigation of unexpected mortality trends in Croatia in the 1990s had been done. Systematic analysis of health patterns should be done as soon as data from the 2001 census become available. Capacities in public health should be strengthened to make this possible. This issue has received little recognition from the international donor organizations, particularly those that use health data

Mitochondrial exchanger NCLX plays a major role in the intracellular Ca(2+) signaling, gliotransmission, and proliferation of astrocytes

Mitochondria not only provide cells with energy, but are central to Ca(2+) signaling. Powered by the mitochondrial membrane potential, Ca(2+) enters the mitochondria and is released into the cytosol through a mitochondrial Na(+)/Ca(2+) exchanger. We established that NCLX, a newly discovered mitochondrial Na(+)/Ca(2+) exchanger, is expressed in astrocytes isolated from mice of either sex. Immunoblot analysis of organellar fractions showed that the location of NCLX is confined to mitochondria. Using pericam-based mitochondrial Ca(2+) imaging and NCLX inhibition either by siRNA or by the pharmacological blocker CGP37157, we demonstrated that NCLX is responsible for mitochondrial Ca(2+) extrusion. Suppression of NCLX function altered cytosolic Ca(2+) dynamics in astrocytes and this was mediated by a strong effect of NCLX activity on Ca(2+) influx via store-operated entry. Furthermore, Ca(2+) influx through the store-operated Ca(2+) entry triggered strong, whereas ER Ca(2+) release triggered only modest mitochondrial Ca(2+) transients, indicating that the functional cross talk between the plasma membrane and mitochondrial domains is particularly strong in astrocytes. Finally, silencing of NCLX expression significantly reduced Ca(2+)-dependent processes in astrocytes (i.e., exocytotic glutamate release, in vitro wound closure, and proliferation), whereas Ca(2+) wave propagation was not affected. Therefore, NCLX, by meditating astrocytic mitochondrial Na(+)/Ca(2+) exchange, links between mitochondria and plasma membrane Ca(2+) signaling, thereby modulating cytoplasmic Ca(2+) transients required to control a diverse array of astrocyte functions

Comparison between simulation results and DEXA investigation of the bone remodelling after implanting a cementless long stem hip prosthesis

Bone remodelling around a femoral prosthesis is one of the main reasons of aseptic loosening of the implant’s stem. The difference in stiffness between the bone tissue and the prosthesis leads to unload the periprosthetic bone and thus to decrease the bone mineral density (BMD), which is known as stress shielding. This paper represents a comparison between measured changes in (BMD) in a periprosthetic Femur with a cementless Bicontact stem by prospective dualenergy X-ray absorptiometry study (DEXA)and calculated changes of the (BMD) using a finite element method (FEM). As a result, it is determined that the total deviation between the two investigations is about 18%.DF

Determining V(ub) from B+ --> D*+(s) e+ e- and B+ --> D*+ e+ e-

It was recently pointed out that the decays B^+ --> D^{*+}_s gamma and B^+ --> D^{*+} gamma can be used for an extraction of |V_{ub}|. The theory of these decays is poorly understood. It was shown that in a world of almost degenerate b and c-quarks the decay would be computable. The severe difficulties that are encountered in the realistic calculation stem primarily from the very hard photon produced in the two body decay. We point out that in the decays B^+ --> D^{*+}_s e^+e^- and B^+ --> D^{*+} e^+e^- the photon vertex is soft when the charmed meson is nearly at rest (in the B^+ rest frame). This allows us to compute with some confidence the decay rate in a restricted but interesting kinematic regime. Given enough data the extraction of V_{ub} with reasonably small uncertainties could proceed through an analysis of these exclusive decays much as is done in the determination of V_{cb}.Comment: 9 pages, latex (revtex), replaced with published versio

Observation of localized modes at phase slips in two-dimensional photonic lattices

We study experimentally light localization at phase-slip waveguides and at the intersection of phase-slips in a two-dimensional (2D) square photonic lattice. Such system allows to observe a variety of effects, including the existence of spatially localized modes for low powers, the generation of strongly localized states in the form of discrete bulk and surface solitons, as well as a crossover between one-dimensional (1D) and 2D localization.Comment: 4 double-column pages, 6 figures, submitted for publicatio

Operator Product Expansion for Exclusive Decays: B^+ ->Ds^+ e+e- and B^+ -> Ds^{*+} e+e-

The decays $B^+\to D_{s,d}^+e^+e^-$ and $B^+\to D_{s,d}^{*+}e^+e^-$ proceed through a weak and an electromagnetic interaction. This is a typical ``long distance'' process, usually difficult to compute systematically. We propose that over a large fraction of phase space a combination of an operator product and heavy quark expansions effectively turns this process into one in which the weak and electromagnetic interactions occur through a local operator. Moreover, we use heavy quark spin symmetry to relate all the local operators that appear in leading order of the operator expansion to two basic ones. We use this operator expansion to estimate the decay rates for $B^+\to D_{s,d}^{(*)+}e^+e^-$.Comment: 4 pages, 1 figure, Latex, published version in PR

Luminescent Bimetallic IrIII /AuI Peptide Bioconjugates as Potential Theranostic Agents

Diverse iridium peptide bioconjugates and the corresponding iridium/gold bimetallic complexes have been synthesized starting from a cyclometallated carboxylic acid substituted IrIII complex [Ir(ppy)2 (Phen-5-COO)] by solid phase peptide synthesis (SPPS). The selected peptide sequences were an enkephalin derivative Tyr-Gly-Gly-Phe-Leu together with the propargyl-substituted species Tyr-Gly-Pgl-Phe-Leu to allow gold coordination (Pgl: propyrgyl-glycine, HC=C-Gly), and a specific short peptide, Ala-Cys-Ala-Phen, containing a cysteine residue. Introduction of the gold center has been achieved via a click reaction with the alkynyl group leading to an organometallic Au-C(triazole) species, or by direct coordination to the sulfur atom of the cysteine. The photophysical properties of these species revealed predominantly an emission originating from the Ir complex, using mixed metal-to-ligand and ligand-to-ligand charge transfer excited states of triplet multiplicity. The formation of the peptide bioconjugates caused a systematic redshift of the emission profiles. Lysosomal accumulation was observed for all the complexes, in contrast to the expected mitochondrial accumulation triggered by the gold complexes. Only the cysteine-containing Ir/Au bioconjugate displayed cytotoxic activity. The absence of activity may be related to the lack of endosomal/lysosomal escape for the cationic peptide conjugates. Interestingly, the different coordination sphere of the gold atom may play a crucial role, as the Au-S(cysteine) bond may be more readily cleaved in a biological environment than the Au-C(triazole) bond, and thus the Au fragment could be released from or trapped in the lysosomes, respectively. This work represents a starting point in the development of bimetallic peptide bioconjugates as theranostics and in the knowledge of factors that contribute to anti-proliferative activity

Early complications after living donor nephrectomy: analysis of the Swiss Organ Living Donor Health Registry.

We evaluated the prospectively collected data about the incidence of early peri- and postoperative complications, and potential risk factors for adverse outcomes after living kidney donation in Switzerland. Peri- and postoperative events were prospectively recorded on a questionnaire by the local transplant teams of all Swiss transplant centres and evaluated by the Swiss Organ Living Donor Health Registry. Complications were classified according to the Clavien grading system. A total of 1649 consecutive donors between 1998 and 2015 were included in the analysis. There was no perioperative mortality observed. The overall complication rate was 13.5%. Major complications defined as Clavien ≥3 occurred in 2.1% of donors. Obesity was not associated with any complications. Donor age >70years was associated with major complications (odds ratio [OR] 3.99) and genitourinary complications (urinary tract infection OR 5.85; urinary retention OR 6.61). There were more major complications observed in donors with laparoscopic surgery versus open surgery (p = 0.048), but an equal overall complication rate (p = 0.094). We found a low rate of major and minor complications, independent of surgical technique, after living donor nephrectomy. There was no elevated complication rate in obese donors. In contrast, elderly donors >70 years had an elevated risk for perioperative complications