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Coupling the notoriously non-emissive complex [Ru(tpy)(bpy)Cl]Cl (tpy = 2,2′:6′,2′′-terpyridine, bpy = 2,2′-bipyridine) to a C12 alkyl chain via an amide linker on the 4′ position of the terpyridine yielded a new amphiphilic ruthenium complex showing red emission and chloride-dependent aggregation properties. This emissive complex is highly cytotoxic in A549 non-small lung cancer cells where it can be followed by confocal microscopy. Uptake occurs within minutes, first by insertion into the cellular membrane, and then by migration to the peri-nuclear region. [ABSTRACT FROM AUTHOR]

A serosurvey involving 2,520 small mammals from Tanzania identified a hot spot of arenavirus circulation in Morogoro. Molecular screening detected a new arenavirus in Natal multimammate mice (Mastomys natalensis), Morogoro virus, related to Mopeia virus. Only a small percentage of mice carry Morogoro virus, although a large proportion shows specific antibodies. [ABSTRACT FROM AUTHOR]

Category: Arthroscopy Introduction/Purpose: The purpose of this study is to prospectively evaluate the clinical and radiographic outcomes of using allograft cartilage extracellular matrix (ECM) as an adjuvant when arthroscopically treating osteochondral lesions of the talar dome (OLT). Methods: Between May 2012 and September 2014, 22 patients presented with an OLT amenable to arthroscopic surgery. All patients received an excision, micro-fracture, and injectable allograft cartilage ECM (BioCartilage, Arthrex, Naples, FL) at the OLT. Preoperative and postoperative function and pain was graded using the Foot and Ankle Ability Measures (FAAM) and a Visual Analog Scale (VAS) respectively. At 6 months from surgery, post-operative radiographs and computed tomography were assessed for osteochondral healing. Final radiographs were evaluated for OLT recurrence and ankle degenerative changes. Data regarding postoperative complications and revision surgeries were also recorded. Results: All 22 patients that received arthroscopic treatment of their OLT with allograft cartilage ECM were evaluated with a mean follow-up time of 20.2 months. The mean FAAM score increased from 51.4 of 100 preoperatively to 87.3 of 100 at the time of final follow-up. The mean VAS pain score decreased from 8.1 of 10 preoperatively to 1.9 of 10 at final follow-up. These differences between pre-surgical and post-surgical functional and pain scoring are statistically significant (P < 0.05). At 6 months from surgery, two patients (9.1%) received CT scans that revealed incomplete chondral formation at their OLT. One of these patients was symptomatic from this and ultimately required revision surgical treatment, involving an ankle arthrotomy and osteochondral autograft plugs from the ipsilateral lateral distal femoral condyle, to achieve full talar chondral healing. At final follow-up, one patient (4.5%) developed symptomatic and radiographic ankle degenerative changes at 1 year from surgery. Conclusion: Outcomes from arthroscopically treating OLTs with excision, micro-fracture, and application of allograft cartilage ECM has not been previously reported in the orthopaedic literature. This study demonstrates that using allograft cartilage ECM as an adjuvant to traditional ankle arthroscopic technique results in a high rate of improving ankle function and pain relief in patients with OLTs.

Photoinduced ionization of the chromophore inside photoactive yellow protein (PYP) was investigated by ultrafast spectroscopy in the visible-near infrared spectral region. A solvated electron absorption-like band was observed that extended from around 550nm to 850nm, centred at 700nm. Simulation of the decay traces of the band with a classic diffusion model indicated that ejected electrons were located an average distance of ~3Å away from the radical centre, and around 40% the solvated electrons were annihilated by geminate recombination. The remaining 60% escaped out of the protein pocket to be annihilated by bulk recombination. This result indicates that the chromophore is in a local environment inside PYP that is only slightly different from the bath solvent.

UV/visible pump, mid-IR probe spectroscopy measurements based on the chirped upconversion method were expanded to the frequency region below 1800cm−1 with the nonlinear optical crystal AgGaGeS4. Pump-probe experiments were demonstrated with GaAs and the photoreceptor protein Slr1694.

Developing tools for visualizing DNA sequences is an important issue in the Barcoding context. Visualizing Barcode data can be put in a purely statistical context, unsupervised learning. Clustering methods combined with projection methods have two closely linked objectives, visualizing and finding structure in the data. Multidimensional scaling (MDS) and Self-organizing maps (SOM) are unsupervised statistical tools for data visualization. Both algorithms map data onto a lower dimensional manifold: MDS looks for a projection that best preserves pairwise distances while SOM preserves the topology of the data. Both algorithms were initially developed for Euclidean data and the conditions necessary to their good implementation were not satisfied for Barcode data. We developed a workflow consisting in four steps: collapse data into distinct sequences; compute a dissimilarity matrix; run a modified version of SOM for dissimilarity matrices to structure the data and reduce dimensionality; project the results using MDS. This methodology was applied to Astraptes fulgerator and Hylomyscus, an African rodent with debated taxonomy. We obtained very good results for both data sets. The results were robust against unbalanced species. All the species in Astraptes were well displayed in very distinct groups in the various visualizations, except for LOHAMP and FABOV that were mixed up. For Hylomyscus, our findings were consistent with known species, confirmed the existence of four unnamed taxa and suggested the existence of potentially new species., (© 2013 John Wiley & Sons Ltd.)

The Praomyini tribe is one of the most diverse and abundant groups of Old World rodents. Several species are known to be involved in crop damage and in the epidemiology of several human and cattle diseases. Due to the existence of sibling species their identification is often problematic. Thus an easy, fast and accurate species identification tool is needed for non-systematicians to correctly identify Praomyini species. In this study we compare the usefulness of three genes (16S, Cytb, CO1) for identifying species of this tribe. A total of 426 specimens representing 40 species (sampled across their geographical range) were sequenced for the three genes. Nearly all of the species included in our study are monophyletic in the neighbour joining trees. The degree of intra-specific variability tends to be lower than the divergence between species, but no barcoding gap is detected. The success rate of the statistical methods of species identification is excellent (up to 99% or 100% for statistical supervised classification methods as the k-Nearest Neighbour or Random Forest). The 16S gene is 2.5 less variable than the Cytb and CO1 genes. As a result its discriminatory power is smaller. To sum up, our results suggest that using DNA markers for identifying species in the Praomyini tribe is a largely valid approach, and that the CO1 and Cytb genes are better DNA markers than the 16S gene. Our results confirm the usefulness of statistical methods such as the Random Forest and the 1-NN methods to assign a sequence to a species, even when the number of species is relatively large. Based on our NJ trees and the distribution of all intraspecific and interspecific pairwise nucleotide distances, we highlight the presence of several potentially new species within the Praomyini tribe that should be subject to corroboration assessments.

Carotenoids are important biomolecules that are ubiquitous in nature and find widespread application in medicine. In photosynthesis, they have a large role in light harvesting (LH) and photoprotection. They exert their LH function by donating their excited singlet state to nearby (bacterio)chlorophyll molecules. In photosynthetic bacteria, the efficiency of this energy transfer process can be as low as 30%. Here, we present evidence that an unusual pathway of excited state relaxation in carotenoids underlies this poor LH function, by which carotenoid triplet states are generated directly from carotenoid singlet states. This pathway, operative on a femtosecond and picosecond timescale, involves an intermediate state, which we identify as a new, hitherto uncharacterized carotenoid singlet excited state. In LH complex-bound carotenoids, this state is the precursor on the reaction pathway to the triplet state, whereas in extracted carotenoids in solution, this state returns to the singlet ground state without forming any triplets. We discuss the possible identity of this excited state and argue that fission of the singlet state into a pair of triplet states on individual carotenoid molecules constitutes the mechanism by which the triplets are generated. This is, to our knowledge, the first ever direct observation of a singlet-to-triplet conversion process on an ultrafast timescale in a photosynthetic antenna.

Immunocytochemistry was used to identify glial cell line-derived neurotrophic factor (GDNF) in rat spinal cord. Strong GDNF labeling was found in fibers and terminals in laminae I and II (outer) and to a lesser extent in the remaining laminae. A few spinal ganglion cells also contained GDNF. After dorsal root transection GDNF disappeared from the dorsal horn and after dorsal root ligation there was accumulation of GDNF only on the ganglion side of the ligation. These findings demonstrate anterograde transport of GDNF within primary afferent fibers, which constitute the only source of GDNF labeling in the dorsal horn. The strong presence of GDNF in the superficial dorsal horn may indicate that GDNF has a role in pain transmission in the adult rat spinal cord.

Femtosecond transient absorption spectroscopy in the range of 500-1040 nm was used to study electron transfer at 5 K in reaction centers of Rhodobacter sphaeroides R26 in which the bacteriopheophytins (BPhe) were replaced by plant pheophytin a (Phe). Primary charge separation took place with a time constant of 1.6 ps, similar to that found in native RCs. Spectral changes around 1020 nm indicated the formation of reduced bacteriochlorophyll (BChl) with the same time constant, and its subsequent decay in 620 ps. This observation identifies the accessory BChl as the primary electron acceptor. No evidence was found for electron transfer to Phe, indicating that electron transfer from BA- occurs directly to the quinone (QA) through superexchange. The results are explained by a model in which the free energy level of P+Phe- lies above that of P+BA-, which itself is below P*. Assuming that the pigment exchange does not affect the energy levels of P* and P+BA-, our results strongly support a two-step model for primary electron transfer in the native bacterial RC, with no, or very little, admixture of superexchange.

After sciatic transection a strong decrease in immunoreactivity occurred, starting at 2 days. After 6, 10, 14, and 20 days survival only 5% of the sciatic motoneurons were strongly labeled for GluR2/3 against 80% in the control situation. From Day 20, GluR2/3 labeling started to increase again, reaching near normal levels at Day 80 after sciatic transection. In contrast, after sciatic crush, the decrease in GluR2/3 labeling in motoneurons was less pronounced and returned to normal in 30 days. In all animals, the GluR1 and GluR4 labeling of motoneurons remained unchanged after sciatic transection or crush. It is concluded that sciatic nerve injury leads to a strong, time-dependent decrease in the expression of GluR2 and 3 subunits in the corresponding motoneurons. As a consequence, AMPA receptors with a different subunit composition may be assembled, leading to a change in the functional properties of these receptors. Moreover, if they lack the GluR2 subunit, they may become calcium permeable.