Laparoscopic sacrocolpopexy in a patient with vault prolapse of the sigmoid stump.

Surgical creation of a neovagina using the sigmoid was one of the main techniques used in patients with Mayer-Rokinatsky-Küster-Hauser syndrome. Nowadays, this surgery is not common as a result of the high frequency of complications and adverse outcomes, one of which is sigmoid neovagina prolapse. There are no standards of treatment because of the rarity of these clinical events; therefore, any medical case is important. We present a case report of a 72-year-old patient with prolapse of the sigmoid stump. Perscrutation of this example allows us to conclude that laparoscopic sacrocolpopexy is the optimal operation for patients with apical prolapse and a history of sigmoidal colpopoiesis owing to its high level of safety and excellent outcomes.

An energy transfer kinetic probe for OH-quenchers in the Nd(3+):YPO4 nanocrystals suitable for imaging in the biological tissue transparency window.

Tetragonal xenotime-type yttrium orthophosphate (YPO4) Nd(3+) doped nanoparticles suitable for biomedical applications were prepared by microwave-hydrothermal treatment. We applied the energy transfer probing based on the analysis of kinetics of impurity quenching to determine the presence and spatial position of -OH fluorescence quenching acceptors in the impurity-containing nanoparticles. We show that the impurity quenching kinetics of the 0.1 at% Nd(3+) doped YPO4 nanoparticles is a two stage (ordered and disordered) static kinetics, determined by a direct energy transfer to the -OH acceptors. Analyzing the ordered stage, we assume that the origin of the -OH groups is the protonation of the phosphate groups, while analyzing the disordered stage, we assume the presence of water molecules in the mesopores. We determine the dimension of the space of the -OH acceptors as d = 3 and quantify their absolute concentration using the disordered Förster stage of kinetics. We use the late stage of kinetics of fluorescence hopping (CDD ≫ CDA) quenching (the fluctuation asymptotics) at 1 at% Nd(3+) concentration as an energy transfer probe to quantify the relative concentration of -OH molecular groups compared to an optically active rare-earth dopant in the volume of NPs, when energy migration over Nd(3+) donors to the -OH acceptors accelerates fluorescence quenching. In doing so we use just one parameter α = γ(A)/γ(D) = n(A)√[C(DA)]/n(D)√[C(DD)], defined by the relation of concentration of the -OH acceptors to the concentration of an optically active dopant. The higher is the α, the higher is the relative concentration of -OH acceptors in the volume of nanoparticles. We find α = 2.95 for the 1 at% Nd(3+):YPO4 NPs that, according to the equation for α, and the results obtained for the values of the microparameters CDD(Nd-Nd) = 24.6 nm(6) ms(-1) and CDA(Nd-OH) = 0.6 nm(6) ms(-1), suggests twenty times higher concentration for acceptors other than donors. As the main result we have established that the majority of -OH acceptors is located not on the surface of the Nd(3+):YPO4 nanoparticles, as many researchers assumed, but in their volume, and can be either associated with crystal structure defects or located in the mesopores.

The Influence of Medium on Fluorescence Quenching of Colloidal Solutions of the Nd3+: LaF3 Nanoparticles Prepared with HTMW Treatment.

An original method was proposed to reduce the quenching of the NIR fluorescence of colloidal solutions of 0.1 at. % Nd3+: LaF3 nanoparticles (NPs) synthesized by aqueous co-precipitation method followed by hydrothermal microwave treatment. For this, an aqueous colloidal solution of NPs was precipitated by centrifugation and dissolved in the same volume of DMSO. The kinetics of static fluorescence quenching of Nd3+ donors of doped NPs dispersed in two solvents was analyzed to determine and to compare the concentrations of OH- quenching acceptors uniformly distributed throughout the volume of the NPs. The dependences of the relative fluorescence quantum yield φ of colloidal solutions on the concentration of OH- groups in the NPs were calculated and were also used to determine concentration of acceptors in the volume of NPs in different solvents. It was found that the concentration of OH- groups in NPs dispersed in DMSO is almost two times lower than in NPs dispersed in water. This gives an almost two-fold increase in the relative fluorescence quantum yield φ for the former. The sizes of synthesized NPs were monitored by common TEM and by applying a rapid procedure based on optical visualization of the trajectories of the Brownian motion of NPs in solution using a laser ultramicroscope. The use of two different methods made it possible to obtain more detailed information about the studied NPs.

The evolution of dog diet and foraging: Insights from archaeological canids in Siberia.

Research on the evolution of dog foraging and diet has largely focused on scavenging during their initial domestication and genetic adaptations to starch-rich food environments following the advent of agriculture. The Siberian archaeological record evidences other critical shifts in dog foraging and diet that likely characterize Holocene dogs globally. By the Middle Holocene, body size reconstruction for Siberia dogs indicates that most were far smaller than Pleistocene wolves. This contributed to dogs' tendencies to scavenge, feed on small prey, and reduce social foraging. Stable carbon and nitrogen isotope analysis of Siberian dogs reveals that their diets were more diverse than those of Pleistocene wolves. This included habitual consumption of marine and freshwater foods by the Middle Holocene and reliance on C4 foods by the Late Holocene. Feeding on such foods and anthropogenic waste increased dogs' exposure to microbes, affected their gut microbiomes, and shaped long-term dog population history.

Stable Aqueous Colloidal Solutions of Nd3+: LaF3 Nanoparticles, Promising for Luminescent Bioimaging in the Near-Infrared Spectral Range.

Two series of stable aqueous colloidal solutions of Nd3+: LaF3 single-phase well-crystallized nanoparticles (NPs), possessing a fluorcerite structure with different activator concentrations in each series, were synthesized. A hydrothermal method involving microwave-assisted heating (HTMW) in two Berghof speedwave devices equipped with one magnetron (type I) or two magnetrons (type II) was used. The average sizes of NPs are 15.4 ± 6 nm (type I) and 21 ± 7 nm (type II). Both types of NPs have a size distribution that is well described by a double Gaussian function. The fluorescence kinetics of the 4F3/2 level of the Nd3+ ion for NPs of both types, in contrast to a similar bulk crystal, demonstrates a luminescence quenching associated not only with Nd-Nd self-quenching, but also with an additional Nd-OH quenching. A method has been developed for determining the spontaneous radiative lifetime of the excited state of a dopant ion, with the significant contribution of the luminescence quenching caused by the presence of the impurity OH- acceptors located in the bulk of NPs. The relative quantum yield of fluorescence and the fluorescence brightness of an aqueous colloidal solution of type II NPs with an optimal concentration of Nd3+ are only 2.5 times lower than those of analogous Nd3+: LaF3 single crystals.

Cryopreservation of protocorm-like bodies of the hybrid orchid Bratonia (Miltonia flavescens × Brassia longissima).

In this study, cryopreservation of Bratonia (Miltonia flavescens (Lindl.) Lindl. × Brassia longissima (Reichb.) Nash), a hybrid tropical orchid, was achieved using protocorm-like bodies (PLBs) multiplied in vitro. Cryopreservation was performed using a vitrification protocol including pretreatment of PLBs with a loading solution (LS, 2.0 M glycerol + 0.4 M sucrose) for 15 min followed by treatment with modified PVS2 vitrification solution (containing PEG instead of ethylene glycol) for 1 h. Increasing benzyladenine (BA) concentration in the recovery medium to 5.0 or 10.0 mg l⁻¹ during the initial 3 weeks after rewarming provided 20.4 % post-cryopreservation regrowth. By contrast, preliminary culture of PLBs with abscisic acid (ABA) and high sucrose concentrations (up to 0.3 M) as well as addition of reduced glutathione during the preculture, loading and post-culture steps were not beneficial. Forty to 45 plants were regenerated from each PLB which withstood cryopreservation. No morphological differences were observed between plants regenerated from cryopreserved and untreated PLBs. Investigations into the functional activity of photosystems I and II in PLBs suggest that electron transport was retained in the reaction centers of both photosystems shortly after cryopreservation.

Photoinduced refractive index variation within picosecond laser pulses excitation as the indicator of oxyorthosilicates single crystals composition modification.

For the first time, the diagnostics of oxyorthosilicates single crystals based on self-action of picosecond range laser pulses at 1,064 nm (1.17 eV) has been performed. High sensitivity of the photoinduced refractive index variation to the substitution of the Lu atoms by Gd in the LSO/LGSO crystalline host as well as to the admixture of Ce was found. The effect can be explained with different electron detrapping-recombination process efficiencies due to the resonant electron excitation from the deep traps in the gap attributed to intrinsic oxygen vacancies.

X-ray-radiation-induced changes in bacteriorhodopsin structure.

Bacteriorhodopsin (bR) provides light-driven vectorial proton transport across a cell membrane. Creation of electrochemical potential at the membrane is a universal step in energy transformation in a cell. Published atomic crystallographic models of early intermediate states of bR show a significant difference between them, and conclusions about pumping mechanisms have been contradictory. Here, we present a quantitative high-resolution crystallographic study of conformational changes in bR induced by X-ray absorption. It is shown that X-ray doses that are usually accumulated during data collection for intermediate-state studies are sufficient to significantly alter the structure of the protein. X-ray-induced changes occur primarily in the active site of bR. Structural modeling showed that X-ray absorption triggers retinal isomerization accompanied by the disappearance of electron densities corresponding to the water molecule W402 bound to the Schiff base. It is demonstrated that these and other X-ray-induced changes may mimic functional conformational changes of bR leading to misinterpretation of the earlier obtained X-ray crystallographic structures of photointermediates.