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Optics Express May 2024We report the femtosecond laser writing of meter-long optical waveguides inscribed through the coating of specifically designed optical fibers. In order to improve the...
We report the femtosecond laser writing of meter-long optical waveguides inscribed through the coating of specifically designed optical fibers. In order to improve the material photosensitivity and to ensure non-guiding optical fibers for subsequent laser processing of the waveguiding core, a depressed refractive index core design is implemented by co-doping a large portion of the optical fiber with germanium oxide and fluorine. The enhanced photosensitivity provided by further deuterium loading these fibers allows laser-writing of large refractive index contrast waveguides over wide cross sections. To mitigate the formation of photoinduced color centers causing high propagation losses in the photo-written waveguides, thermal annealing up to 400°C is performed on polyimide-coated laser-written fibers. Although the refractive index contrast decreases, the propagation losses are drastically reduced down to 0.08 dB/cm at 900nm allowing a robust single-mode guiding from visible to near infrared. Our results pave the way towards the development of a new generation of optical fibers and photonic components with arbitrarily complex designs.
PubMed: 38859101
DOI: 10.1364/OE.521714 -
ACS Omega Jun 2024The mode of action of antibiotics can be broadly classified as bacteriostatic and bactericidal. The bacteriostatic mode leads to the arrested growth of the cells, while...
The mode of action of antibiotics can be broadly classified as bacteriostatic and bactericidal. The bacteriostatic mode leads to the arrested growth of the cells, while the bacteriocidal mode causes cell death. In this work, we report the applicability of deuterium stable isotope probing (DSIP) in combination with Raman spectroscopy (Raman DSIP) for discriminating the mode of action of antibiotics at the community level. a well-known model microbe, was used as an organism for the study. We optimized the concentration of deuterium oxide required for metabolic activity monitoring without compromising the microbial growth. Our findings suggest that changes in the intensity of the C-D band in the high-wavenumber region could serve as a quantifiable marker for determining the antibiotic mode of action. This can be used for early identification of the antibiotic's mode of action. Our results explore the new perspective that supports the utility of deuterium-based vibrational tags in the field of clinical spectroscopy. Understanding the antibiotic's mode of action on bacterial cells in a short and objective manner can significantly enhance the clinical management abilities of infectious diseases and may also help in personalized antimicrobial therapy.
PubMed: 38854576
DOI: 10.1021/acsomega.4c01666 -
Water Research Jun 2024High-valent metal-oxo species (HMOS) have been extensively recognized in advanced oxidation processes (AOPs) owing to their high selectivity and high chemical...
High-valent metal-oxo species (HMOS) have been extensively recognized in advanced oxidation processes (AOPs) owing to their high selectivity and high chemical utilization efficiency. However, the interactions between HMOS and halide ions in sewage wastewater are complicated, leading to ongoing debates on the intrinsic reactive species and impacts on remediation. Herein, we prepared three typical HMOS, including Fe(IV), Mn(V)-nitrilotriacetic acid complex (Mn(V)NTA) and Co(IV) through peroxymonosulfate (PMS) activation and comparatively studied their interactions with Cl to reveal different reactive chlorine species (RCS) and the effects of HMOS types on RCS generation pathways. Our results show that the presence of Cl alters the cleavage behavior of the peroxide OO bond in PMS and prohibits the generation of Fe(IV), spontaneously promoting SO production and its subsequent transformation to secondary radicals like Cl and Cl. The generation and oxidation capacity of Mn(V)NTA was scarcely influenced by Cl, while Cl would substantially consume Co(IV) and promote HOCl generation through an oxygen-transfer reaction, evidenced by density functional theory (DFT) and deuterium oxide solvent exchange experiment. The two-electron-transfer standard redox potentials of Fe(IV), Mn(V)NTA and Co(IV) were calculated as 2.43, 2.55 and 2.85 V, respectively. Due to the different reactive species and pathways in the presence of Cl, the amounts of chlorinated by-products followed the order of Co(II)/PMS > Fe(II)/PMS > Mn(II)NTA/PMS. Thus, this work renovates the knowledge of halide chemistry in HMOS-based systems and sheds light on the impact on the treatment of salinity-containing wastewater.
Topics: Oxidation-Reduction; Chlorides; Chlorine; Metals; Halogenation; Water Pollutants, Chemical; Wastewater
PubMed: 38728779
DOI: 10.1016/j.watres.2024.121715 -
Translational Exercise Biomedicine May 2024'OMICs encapsulates study of scaled data acquisition, at the levels of DNA, RNA, protein, and metabolite species. The broad objectives of OMICs in biomedical exercise... (Review)
Review
OBJECTIVES
'OMICs encapsulates study of scaled data acquisition, at the levels of DNA, RNA, protein, and metabolite species. The broad objectives of OMICs in biomedical exercise research are multifarious, but commonly relate to biomarker development and understanding features of exercise adaptation in health, ageing and metabolic diseases.
METHODS
This field is one of exponential technical (i.e., depth of feature coverage) and scientific (i.e., in health, metabolic conditions and ageing, multi-OMICs) progress adopting and approaches.
RESULTS
Key findings in exercise biomedicine have led to the identification of OMIC features linking to heritability or adaptive responses to exercise e.g., the forging of GWAS/proteome/metabolome links to cardiovascular fitness and metabolic health adaptations. The recent addition of stable isotope tracing to proteomics ('dynamic proteomics') and metabolomics ('fluxomics') represents the next phase of state-of-the-art in 'OMICS.
CONCLUSIONS
These methods overcome limitations associated with point-in-time 'OMICs and can be achieved using substrate-specific tracers or deuterium oxide (DO), depending on the question; these methods could help identify how individual protein turnover and metabolite flux may explain exercise responses. We contend application of these methods will shed new light in translational exercise biomedicine.
PubMed: 38660119
DOI: 10.1515/teb-2024-2006 -
Journal of Animal Science Jan 2024The aim of the study was to investigate whether increased inclusion of sugar beet pulp (SBP) alters retention of fat, protein, and energy when backfat (BF) is restored...
The aim of the study was to investigate whether increased inclusion of sugar beet pulp (SBP) alters retention of fat, protein, and energy when backfat (BF) is restored in early- and mid-gestation. In total, 46 sows were fed one of four dietary treatments with increasing inclusion of SBP providing dietary fiber (DF) levels of 119, 152, 185, and 217 g/kg; sows were assigned to one of three feeding strategies (FS; high, medium, and low) depending on BF thickness at mating and again at day 30 for the following month. On days 0, 30, 60, and 108, body weight (BW) and BF thickness were measured and body pools of protein and fat were estimated using the deuterium oxide technique. On days 30 and 60, urine, feces, and blood samples were collected to quantify metabolites, energy, and nitrogen (N) balances. On days 15 and 45, heart rate was recorded to estimate heat energy. At farrowing, total born and weight of the litter were recorded. In early gestation, BW gain (P < 0.01) and body protein retention increased (P < 0.05) with increasing fiber inclusion, while body fat retention increased numerically by 59%. The increase in BF was greatest for sows fed the high FS, intermediate when fed the medium strategy, and negligible for sows fed the lowest FS (P < 0.001). Nitrogen intake, N loss in feces, and N balance increased linearly, whereas N loss in urine tended to decrease with increasing inclusion of fibers in early gestation. Concomitantly, fecal energy output and energy lost as methane increased linearly (P < 0.001), while energy output in urine declined linearly. Total metabolizable energy (ME) intake therefore increased from 36.5 MJ ME/d in the low fiber group to 38.5 MJ ME/d in the high fiber group (P < 0.01). Changing the ME towards more ketogenic energy was expected to favor fat retention rather than protein retention. However, due to increased intake of ME and increased N efficiency with increasing fiber inclusion, the sows gained more weight and protein with increasing fiber inclusion. In conclusion, increased feed intake improved both fat and protein retention, whereas increased DF intake increased protein retention.
Topics: Animals; Dietary Fiber; Female; Animal Feed; Pregnancy; Energy Metabolism; Animal Nutritional Physiological Phenomena; Diet; Swine; Beta vulgaris; Adipose Tissue
PubMed: 38659196
DOI: 10.1093/jas/skae092 -
Journal of Animal Science Jan 2024The aim of the present study was to determine the optimal concentration of dietary protein required in transition diets for multiparous sows that enhance the farrowing...
The aim of the present study was to determine the optimal concentration of dietary protein required in transition diets for multiparous sows that enhance the farrowing process, colostrum production, and subsequent lactation performance. Forty-eight multiparous sows were allotted to one of six dietary treatments according to body weight (290 ± 3 kg) and parity (3.8 ± 0.2) from day 108 of gestation until 24 h after the onset of farrowing. The diets were isoenergetic and contained increasing concentrations of dietary protein (expressed as standardized ileal digestible [SID] Lys) and were supplied at a daily feed supply of 3.8 kg. On day 108 of gestation and days 2, 7, 14, 21, and 28 of lactation, body weight, and back fat thickness were recorded, and blood was sampled on day 108 of gestation, at the onset of farrowing, and days 3, 10, 17, and 24 of lactation from the sows for analysis of plasma metabolites. On day 115 of gestation, urine, and feces were collected for nitrogen (N) balance. The number of liveborn and stillborn piglets and time of birth were recorded and blood from every fourth piglet was sampled at birth for blood gas analysis. Piglets were weighed individually from birth until weaning, to estimate the colostrum and milk yield of the sows. Colostrum and milk samples were collected, and their compositions were determined. On days 3 and 28 of lactation, sows were injected with deuterium oxide to estimate body composition. The N utilization was maximized when the concentration of SID Lys in the transition diet was 6.06 g/kg (P < 0.01). When urinary concentrations of urea were expressed relative to creatinine, the relative concentration of urea remained low until a dietary concentration of 6.08 g SID Lys/kg, above which the relative concentration of urea increased (P < 0.01). Stillbirth rate increased linearly with increasing SID Lys concentration in the transition diet (P < 0.001), thus the concentration of SID Lys should be kept as low as possible without impairing sow performance excessively. A carry-over effect on milk yield was observed, showing that a dietary SID Lys concentration of 5.79 g/kg during transition optimized milk production at an average yield of 13.5 kg/d (P = 0.04). Increasing loss of body fat in lactation was observed with increasing SID Lys concentration in the transition diet (P = 0.03). In conclusion, the transition diet of multiparous sows should contain 5.79 g SID Lys/kg when fed 3.8 kg/d (13.0 MJ ME/kg), for a total SID Lys intake of 22 g/d.
Topics: Pregnancy; Animals; Swine; Female; Diet; Lactation; Body Weight; Dietary Proteins; Urea; Animal Feed
PubMed: 38517473
DOI: 10.1093/jas/skae082 -
Proceedings of the National Academy of... Mar 2024Water microdroplets (7 to 11 µm average diameter, depending on flow rate) are sprayed in a closed chamber at ambient temperature, whose relative humidity (RH) is...
Water microdroplets (7 to 11 µm average diameter, depending on flow rate) are sprayed in a closed chamber at ambient temperature, whose relative humidity (RH) is controlled. The resulting concentration of ROS (reactive oxygen species) formed in the microdroplets, measured by the amount of hydrogen peroxide (HO), is determined by nuclear magnetic resonance (NMR) and by spectrofluorimetric assays after the droplets are collected. The results are found to agree closely with one another. In addition, hydrated hydroxyl radical cations (•OH-HO) are recorded from the droplets using mass spectrometry and superoxide radical anions (•O) and hydroxyl radicals (•OH) by electron paramagnetic resonance spectroscopy. As the RH varies from 15 to 95%, the concentration of HO shows a marked rise by a factor of about 3.5 in going from 15 to 50%, then levels off. By replacing the HO of the sprayed water with deuterium oxide (DO) but keeping the gas surrounding droplets with HO, mass spectrometric analysis of the hydrated hydroxyl radical cations demonstrates that the water in the air plays a dominant role in producing HO and other ROS, which accounts for the variation with RH. As RH increases, the droplet evaporation rate decreases. These two facts help us understand why viruses in droplets both survive better at low RH values, as found in indoor air in the wintertime, and are disinfected more effectively at higher RH values, as found in indoor air in the summertime, thus explaining the recognized seasonality of airborne viral infections.
PubMed: 38489384
DOI: 10.1073/pnas.2315940121 -
International Journal of Molecular... Mar 2024Liquid chromatography with mass spectrometry (LC-MS)-based metabolomics detects thousands of molecular features (retention time-/ pairs) in biological samples per...
Liquid chromatography with mass spectrometry (LC-MS)-based metabolomics detects thousands of molecular features (retention time-/ pairs) in biological samples per analysis, yet the metabolite annotation rate remains low, with 90% of signals classified as unknowns. To enhance the metabolite annotation rates, researchers employ tandem mass spectral libraries and challenging in silico fragmentation software. Hydrogen/deuterium exchange mass spectrometry (HDX-MS) may offer an additional layer of structural information in untargeted metabolomics, especially for identifying specific unidentified metabolites that are revealed to be statistically significant. Here, we investigate the potential of hydrophilic interaction liquid chromatography (HILIC)-HDX-MS in untargeted metabolomics. Specifically, we evaluate the effectiveness of two approaches using hypothetical targets: the post-column addition of deuterium oxide (DO) and the on-column HILIC-HDX-MS method. To illustrate the practical application of HILIC-HDX-MS, we apply this methodology using the in silico fragmentation software MS-FINDER to an unknown compound detected in various biological samples, including plasma, serum, tissues, and feces during HILIC-MS profiling, subsequently identified as -acetylspermidine.
Topics: Deuterium; Chromatography, Liquid; Metabolomics; Hydrogen Deuterium Exchange-Mass Spectrometry; Hydrophobic and Hydrophilic Interactions
PubMed: 38474147
DOI: 10.3390/ijms25052899 -
Pflugers Archiv : European Journal of... Jun 2024Increase in transendothelial water permeability is an essential etiological factor in a variety of diseases like edema and shock. Despite the high clinical relevance,...
Increase in transendothelial water permeability is an essential etiological factor in a variety of diseases like edema and shock. Despite the high clinical relevance, there has been no precise method to detect transendothelial water flow until now. The deuterium oxide (DO) dilution method, already established for measuring transepithelial water transport, was used to precisely determine the transendothelial water permeability. It detected appropriate transendothelial water flow induced by different hydrostatic forces. This was shown in four different endothelial cell types. The general experimental setup was verified by gravimetry and absorbance spectroscopy. Determination of transendothelial electrical resistance (TEER) and immunocytochemical staining for proteins of the cell-cell contacts were performed to ensure that no damage to the endothelium occurred because of the measurements. Furthermore, endothelial barrier function was modulated. Measurement of transendothelial water flux was verified by measuring the TEER, the apparent permeability coefficient and the electrical capacity. The barrier-promoting substances cyclic adenosine monophosphate and iloprost reduced TEER and electrical capacity and increased permeability. This was accompanied by a reduced transendothelial water flux. In contrast, the barrier-damaging substances thrombin, histamine and bradykinin reduced TEER and electrical capacity, but increased permeability. Here, an increased water flow was shown. This newly established in vitro method for direct measurement of transendothelial water permeability was verified as a highly precise technique in various assays. The use of patient-specific endothelial cells enables individualized precision medicine in the context of basic edema research, for example regarding the development of barrier-protective pharmaceuticals.
Topics: Deuterium Oxide; Humans; Electric Impedance; Water; Endothelial Cells; Permeability; Animals; Endothelium, Vascular; Capillary Permeability; Human Umbilical Vein Endothelial Cells
PubMed: 38438679
DOI: 10.1007/s00424-024-02934-z -
Biochemistry Mar 2024Production of soluble proteins is essential for structure/function studies; however, this usually requires milligram amounts of protein, which can be difficult to obtain...
Production of soluble proteins is essential for structure/function studies; however, this usually requires milligram amounts of protein, which can be difficult to obtain with traditional expression systems. Recently, the Gram-negative bacterium emerged as a novel and alternative host platform for production of proteins in high yields. Here, we used a commercial strain derived from (Vmax X2) to produce soluble bacterial and fungal proteins in milligram scale, which we struggled to achieve in . These proteins include the cholera toxin (CT) and -acetyl glucosamine-binding protein A (GbpA) from , the heat-labile enterotoxin (LT) from and the fungal nematotoxin CCTX2 from . CT, GbpA, and LT are secreted by the Type II secretion system in their natural hosts. When these three proteins were produced in Vmax, they were also secreted and could be recovered from the growth media. This simplified the downstream purification procedure and resulted in considerably higher protein yields compared to production in (6- to 26-fold increase). We also tested Vmax for protein perdeuteration using deuterated minimal media with deuterium oxide as solvent and achieved a 3-fold increase in yield compared to the equivalent protocol in . This is good news, since isotopic labeling is expensive and often ineffective but represents a necessary prerequisite for some structural biology techniques. Thus, Vmax represents a promising host for production of challenging expression targets and for protein perdeuteration in amounts suitable for structural biology studies.
Topics: Escherichia coli; Vibrio; Enterotoxins; Cholera Toxin
PubMed: 38359344
DOI: 10.1021/acs.biochem.3c00612