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Infection and Drug Resistance 2023Antibiotic resistance represents a serious global health challenge, particularly with the emergence of strains resistant to last-resort antibiotics such as tigecycline,...
BACKGROUND
Antibiotic resistance represents a serious global health challenge, particularly with the emergence of strains resistant to last-resort antibiotics such as tigecycline, polymyxin B, and vancomycin. Urgent measures are required to alleviate this situation. To facilitate the judicious use of antibiotics, rapid and precise antimicrobial susceptibility testing (AST) is essential. Heavy water (deuterium oxide, DO)-labeled Raman spectroscopy has emerged as a promising time-saving tool for microbiological testing.
METHODS
Deuterium incorporation and experimental conditions were examined to develop and apply a Raman-based AST method to evaluate the efficacy of last-resort antibiotics, including tigecycline, polymyxin B, and vancomycin, against , and . Essential agreement and categorical agreement were used to assess the metabolism inactivation concentration based on Raman spectroscopy (R-MIC)-a new metric developed in this study-and minimum inhibitory concentration (MIC) determined via the traditional microdilution broth method. Spearman's rank correlation coefficient was employed to measure the association between R-MIC and MIC values.
RESULTS
The Raman-based AST method achieved a 100% categorical agreement (92/92) with the traditional microdilution broth method within five hours, while the traditional method required approximately 24 h. The R-MIC values shared 68.5% (63/92) consistency with the MIC values. In addition, the R-MIC and MIC values were highly correlated (Spearman's r=0.96), resulting in an essential agreement of 100%.
CONCLUSION
Our optimized experimental method and conditions indicate that Raman-based AST holds great promise as a solution to overcome the time-consuming challenges of traditional AST methods.
PubMed: 37638072
DOI: 10.2147/IDR.S404732 -
PeerJ 2014For the first time we show the effects of deuterium oxide on cell growth and vesicle transport in rat basophilic leukemia (RBL-2H3) cells. RBL-2H3 cells cultured with 15...
For the first time we show the effects of deuterium oxide on cell growth and vesicle transport in rat basophilic leukemia (RBL-2H3) cells. RBL-2H3 cells cultured with 15 moles/L deuterium showed decreased cell growth which was attributed to cells not doubling their DNA content. Experimental observations also showed an increase in vesicle speed for cells cultured in deuterium oxide. This increase in vesicle speed was not observed in deuterium oxide cultures treated with a microtubule-destabilizing drug, suggesting that deuterium oxide affects microtubule-dependent vesicle transport.
PubMed: 25237603
DOI: 10.7717/peerj.553 -
Maternal & Child Nutrition Oct 2021The World Health Organization recommends deworming to reduce soil-transmitted helminth (STH)-attributable morbidity in women of reproductive age, including pregnant and...
The World Health Organization recommends deworming to reduce soil-transmitted helminth (STH)-attributable morbidity in women of reproductive age, including pregnant and lactating women, to reduce blood loss, iron deficiency anaemia and nutrient malabsorption. This study assessed the impact of maternal postpartum deworming with albendazole approximately 1 day after delivery on infant milk intake among a subset of 216 randomly selected mother-infant pairs recruited into a large trial in Peru. Infant milk intake was measured using the deuterium-oxide method at 1- and 6-month postpartum. Maternal STH infection was measured at 6-month postpartum. At 1-month postpartum, mean intake was 756 ± 16 and 774 ± 18 mL day in the albendazole and placebo groups, respectively (mean difference: -18 mL day ; 95% CI: -65, 30). At 6-month postpartum, mean intake was 903 ± 16 and 908 ± 18 mL day in the albendazole and placebo groups, respectively (mean difference: -5 mL day ; 95% CI: -52, 43). There was no statistically significant difference in milk intake between groups at either time point. At 6-month postpartum, mothers infected with Trichuris trichiura had infants with higher milk intakes (adjusted mean difference: 70 mL day ; 95% CI: 20, 120) compared with uninfected mothers. However, there was no statistically significant difference in infant milk intake between mothers who had moderate-and-heavy intensity infection compared with the comparison group (mothers with no and light intensity infection). A lower prevalence and intensity of infection, and inclusion of uninfected mothers in both arms of the trial, resulting in effect dilution, may explain the null findings.
Topics: Female; Helminthiasis; Humans; Infant; Lactation; Milk, Human; Mothers; Postpartum Period; Pregnancy
PubMed: 33729674
DOI: 10.1111/mcn.13183 -
Journal of Cachexia, Sarcopenia and... Oct 2022Cell assays are important for investigating the mechanisms of ageing, including losses in protein homeostasis and 'proteostasis collapse'. We used novel isotopic...
BACKGROUND
Cell assays are important for investigating the mechanisms of ageing, including losses in protein homeostasis and 'proteostasis collapse'. We used novel isotopic labelling and proteomic methods to investigate protein turnover in replicatively aged (>140 population doublings) murine C2C12 myoblasts that exhibit impaired differentiation and serve as a model for age-related declines in muscle homeostasis.
METHODS
The Absolute Dynamic Profiling Technique for Proteomics (Proteo-ADPT) was used to investigate proteostasis in young (passage 6-10) and replicatively aged (passage 48-50) C2C12 myoblast cultures supplemented with deuterium oxide (D O) during early (0-24 h) or late (72-96 h) periods of differentiation. Peptide mass spectrometry was used to quantify the absolute rates of abundance change, synthesis and degradation of individual proteins.
RESULTS
Young cells exhibited a consistent ~25% rise in protein accretion over the 96-h experimental period. In aged cells, protein accretion increased by 32% (P < 0.05) during early differentiation, but then fell back to baseline levels by 96-h. Proteo-ADPT encompassed 116 proteins and 74 proteins exhibited significantly (P < 0.05, FDR < 5% interaction between age × differentiation stage) different changes in abundance between young and aged cells at early and later periods of differentiation, including proteins associated with translation, glycolysis, cell-cell adhesion, ribosomal biogenesis, and the regulation of cell shape. During early differentiation, heat shock and ribosomal protein abundances increased in aged cells due to suppressed degradation rather than heightened synthesis. For instance, HS90A increased at a rate of 10.62 ± 1.60 ng/well/h in aged which was significantly greater than the rate of accretion (1.86 ± 0.49 ng/well/h) in young cells. HS90A synthesis was similar in young (21.23 ± 3.40 ng/well/h) and aged (23.69 ± 1.13 ng/well/h), but HS90A degradation was significantly (P = 0.05) greater in young (19.37 ± 2.93 ng/well/h) versus aged (13.06 ± 0.76 ng/well/h) cells. During later differentiation the HS90A degradation (8.94 ± 0.38 ng/well/h) and synthesis (7.89 ± 1.28 ng/well/h) declined and were significantly less than the positive net balance between synthesis and degradation (synthesis = 28.14 ± 3.70 ng/well/h vs. degradation = 21.49 ± 3.13 ng/well/h) in young cells.
CONCLUSIONS
Our results suggest a loss of proteome quality as a precursor to the lack of fusion of aged myoblasts. The quality of key chaperone proteins, including HS90A, HS90B and HSP7C was reduced in aged cells and may account for the disruption to cell signalling required for the later stages of differentiation and fusion.
Topics: Animals; Deuterium Oxide; Mice; Myoblasts; Proteome; Proteomics; Ribosomal Proteins
PubMed: 35819316
DOI: 10.1002/jcsm.13034 -
Glycobiology Feb 2021l-Fucose and l-fucose-containing polysaccharides, glycoproteins or glycolipids play an important role in a variety of biological processes. l-Fucose-containing...
l-Fucose and l-fucose-containing polysaccharides, glycoproteins or glycolipids play an important role in a variety of biological processes. l-Fucose-containing glycoconjugates have been implicated in many diseases including cancer and rheumatoid arthritis. Interest in fucose and its derivatives is growing in cancer research, glyco-immunology, and the study of host-pathogen interactions. l-Fucose can be extracted from bacterial and algal polysaccharides or produced (bio)synthetically. While deuterated glucose and galactose are available, and are of high interest for metabolic studies and biophysical studies, deuterated fucose is not easily available. Here, we describe the production of perdeuterated l-fucose, using glyco-engineered Escherichia coli in a bioreactor with the use of a deuterium oxide-based growth medium and a deuterated carbon source. The final yield was 0.2 g L-1 of deuterated sugar, which was fully characterized by mass spectrometry and nuclear magnetic resonance spectroscopy. We anticipate that the perdeuterated fucose produced in this way will have numerous applications in structural biology where techniques such as NMR, solution neutron scattering and neutron crystallography are widely used. In the case of neutron macromolecular crystallography, the availability of perdeuterated fucose can be exploited in identifying the details of its interaction with protein receptors and notably the hydrogen bonding network around the carbohydrate binding site.
Topics: Escherichia coli; Polysaccharides
PubMed: 32601663
DOI: 10.1093/glycob/cwaa059 -
RSC Advances Jan 2019Gel formations and efficient lanthanide luminescence appeared in deuterium oxide (DO) medium instead of light water (HO), and their solvation possibilities by using...
Gel formations and efficient lanthanide luminescence appeared in deuterium oxide (DO) medium instead of light water (HO), and their solvation possibilities by using luminescence lifetimes were discussed. The lanthanide ions in the hydrogel of 1 obtained by HO (abbreviated as HO-Ln1; Ln = Eu, Tb, and Gd) in our previous report act as the coupling part between neighbor molecules for the bundle structure. Here, DO also acts as a medium to form the lanthanide-hydrogel of 1, and increases intensities of luminescence for Tb, because a soft crystalline state reducing resonance thermal relaxation is realized. The gel-formation and luminescence band positions of Ln1 in DO corresponded to those in HO. From the observation of luminescence lifetimes in HO and DO, the number of coordinating water molecules on Eu and Tb were estimated to be around 3 or 4 for both. The luminescence intensity of Eu1 did not increase even in DO, due to a blue shift of the excited triplet state of 1, as compared to that in HO.
PubMed: 35516109
DOI: 10.1039/c8ra08504h -
Osteoarthritis and Cartilage Jun 2022Cartilage collagen has very limited repair potential, though some turnover and incorporation has not been fully excluded. We aim to determine the regional turnover of...
OBJECTIVE
Cartilage collagen has very limited repair potential, though some turnover and incorporation has not been fully excluded. We aim to determine the regional turnover of human osteoarthritis cartilage.
DESIGN
Patients scheduled for knee joint replacement surgery due to osteoarthritis were recruited in this prospective study of four weeks duration. Deuterium oxide (DO) was administered orally by weekly boluses at 70% DO, initially 150 ml followed by three boluses of 50 ml. Cartilage from the medial tibia plateau was sampled centrally, under the meniscus, and from osteophytes and treated enzymatically with hyaluronidase and trypsin. Samples were analysed for deuterium incorporation in alanine using mass spectrometry and for gene expression by real-time reverse transcriptase polymerase chain reaction.
RESULTS
Twenty participants completed the study: mean (SD) age 64 ± 9.1 years, 45% female, BMI 29.5 ± 4.8 kg/m. Enzymatically treated cartilage from central and submeniscal regions showed similar enrichments at 0.063% APE, while osteophytes showed significantly greater enrichment at 0.072% APE (95% confidence interval of difference) [0.004-0.015]). Fractional synthesis rates were similar for central 0.027%/day and submeniscal cartilage 0.022%/day but 10-fold higher in osteophytes 0.22%/day [0.098-0.363]. When compared to central cartilage, submeniscal cartilage had increased gene expression of MMP-3 and decreased lubricin expression. Untreated cartilage had higher turnover (enrichments at 0.073% APE) than enzymatically treated cartilage (0.063% APE).
CONCLUSIONS
In OA, despite regional differences in gene expression, the turnover of the articular cartilage matrix across the entire joint surface is very limited, but higher turnover was observed in osteophyte cartilage.
Topics: Aged; Cartilage, Articular; Collagen; Female; Humans; Knee Joint; Male; Middle Aged; Osteoarthritis, Knee; Osteochondrodysplasias; Osteophyte; Prospective Studies
PubMed: 35358700
DOI: 10.1016/j.joca.2022.03.007 -
The American Journal of Clinical... Apr 2023Human milk provides essential nutrition for infants, and its benefits are well established. We lack data on the influence of maternal nutritional status on milk volume... (Observational Study)
Observational Study
BACKGROUND
Human milk provides essential nutrition for infants, and its benefits are well established. We lack data on the influence of maternal nutritional status on milk volume and composition in low-middle income countries.
OBJECTIVE
We aimed to 1) assess lactation performance (human milk volume, macronutrient composition, and infant energy intake) in Indian females and 2) examine the associations between maternal anthropometry (BMI, percentage body fat) and lactation performance.
METHODS
We conducted an observational study among 232 mother-infant dyads, 2 to 4 mo postpartum in Haryana, India. We used deuterium oxide dose-to-mother technique to measure milk volume and maternal percentage body fat and collected human milk samples to determine macronutrient and energy concentrations. Adjusted multiple linear regression models were used to examine the associations between maternal anthropometry and lactation performance.
RESULTS
The mean BMI and percentage body fat of mothers were 21.7 ± 3.6 kg/m and 29.5 ± 7.7, respectively. Milk volume and macronutrient composition were similar to the reference values (means ± standard deviations: milk volume, 724 ± 184 mL/d; median (25th, 75th percentile); protein, 9.9 (8.3, 11.7) g/L; fat, 41.0 ± 15.2 g/L; energy density, 0.71 ± 0.14 kcal/g; lactose, 65.5 (55.3, 71.3) g/L). Maternal BMI and percentage body fat were not significantly associated with macronutrient composition. Both maternal BMI and percentage body fat were negatively associated with milk volume (-7.0, 95% CI: -12.4, -1.6 mL/d; -3.5, 95% CI: -6.0, -1.1mL/d, respectively) but there were no effects on the total energy intake of infants after adjusting for covariates.
CONCLUSION
Most mothers had a normal BMI and milk of similar composition and volume to reference values. Future work in populations with a greater burden of underweight and/or obesity are needed to examine the underlying mechanisms between maternal body composition and milk volume. This trial was registered at The Clinical Trials Registry- India as CTRI/2017/01/007636.
Topics: Female; Infant; Humans; Nutritional Status; Lactation; Milk, Human; Body Composition; Energy Intake
PubMed: 36773786
DOI: 10.1016/j.ajcnut.2023.02.002 -
Nature Communications Aug 2022Site- and enantioselective incorporation of deuterium into organic compounds is of broad interest in organic synthesis, especially within the pharmaceutical industry....
Site- and enantioselective incorporation of deuterium into organic compounds is of broad interest in organic synthesis, especially within the pharmaceutical industry. While catalytic approaches relying on two-electron reaction manifolds have allowed for stereoselective delivery of a formal deuteride (D) or deuteron (D) at benzylic positions, complementary strategies that make use of one-electron deuterium atom transfer and target non-benzylic positions remain elusive. Here we report a photochemical approach for asymmetric radical deuteration by utilizing readily available peptide- or sugar-derived thiols as the catalyst and inexpensive deuterium oxide as the deuterium source. This metal-free platform enables four types of deuterofunctionalization reactions of exocyclic olefins and allows deuteration at non-benzylic positions with high levels of enantioselectivity and deuterium incorporation. Computational studies reveal that attractive non-covalent interactions are responsible for stereocontrol. We anticipate that our findings will open up new avenues for asymmetric deuteration.
Topics: Alkenes; Catalysis; Deuterium; Light
PubMed: 35915119
DOI: 10.1038/s41467-022-32238-8 -
Asia Pacific Journal of Clinical... 2018Anthropometric equations are widely used to estimate body composition however, are only appropriate for use in populations in which they have been developed and...
BACKGROUND AND OBJECTIVES
Anthropometric equations are widely used to estimate body composition however, are only appropriate for use in populations in which they have been developed and validated. The present study developed anthropometric prediction equations for Indonesian adults and cross-validated them with selected equations used in this population.
METHODS AND STUDY DESIGN
Six hundred Indonesian adults aged between 18- 65 years (292 males and 308 females) were divided equally into development and validation groups. Stature, body weight, skinfold thickness at eight sites, girth at five sites, and bone breadth at four sites were measured. Stepwise multiple regression analysis was used to propose percentage body fat (%BF) prediction equations using measured variables and %BF from the deuterium oxide dilution technique as the reference. The proposed prediction equations were then cross-validated using the validation group and %BF estimated from several existing equations.
RESULTS
Proposed prediction equations showed r ranged from 0.82 to 0.86 and Standard Error of the Estimate (SEE) from 4.7 to 5.4%. Cross-validation analysis showed bias with the reference %BF between 0.2 and 3.3% and Pure Error (PE) between 2.8 and 4.0%. Among the existing equations, the Durnin and Womersley equation was applicable in females whilst the equation by Davidson et al. underestimated %BF by 6.3-6.6% and the equation by Gurrici et al overestimated by 2.0-3.4% in both genders (p<0.01).
CONCLUSION
The proposed prediction equations provide better options for accurate prediction of %BF in Indonesian adults.
Topics: Adiposity; Adolescent; Adult; Anthropometry; Body Mass Index; Female; Humans; Indonesia; Male; Middle Aged; Skinfold Thickness; Young Adult
PubMed: 29737806
DOI: 10.6133/apjcn.092017.02