Structural and biochemical characterization of the key components of an auxin degradation operon from the rhizosphere bacterium Variovorax.

Plant-associated bacteria play important regulatory roles in modulating plant hormone auxin levels, affecting the growth and yields of crops. A conserved auxin degradation (iad) operon was recently identified in the Variovorax genomes, which is responsible for root growth inhibition (RGI) reversion, promoting rhizosphere colonization and root growth. However, the molecular mechanism underlying auxin degradation by Variovorax remains unclear. Here, we systematically screened Variovorax iad operon products and identified 2 proteins, IadK2 and IadD, that directly associate with auxin indole-3-acetic acid (IAA). Further biochemical and structural studies revealed that IadK2 is a highly IAA-specific ATP-binding cassette (ABC) transporter solute-binding protein (SBP), likely involved in IAA uptake. IadD interacts with IadE to form a functional Rieske non-heme dioxygenase, which works in concert with a FMN-type reductase encoded by gene iadC to transform IAA into the biologically inactive 2-oxindole-3-acetic acid (oxIAA), representing a new bacterial pathway for IAA inactivation/degradation. Importantly, incorporation of a minimum set of iadC/D/E genes could enable IAA transformation by Escherichia coli, suggesting a promising strategy for repurposing the iad operon for IAA regulation. Together, our study identifies the key components and underlying mechanisms involved in IAA transformation by Variovorax and brings new insights into the bacterial turnover of plant hormones, which would provide the basis for potential applications in rhizosphere optimization and ecological agriculture.

A C-terminal glutamine recognition mechanism revealed by E3 ligase TRIM7 structures.

The E3 ligase TRIM7 has emerged as a critical player in viral infection and pathogenesis. However, the mechanism governing the TRIM7-substrate association remains to be defined. Here we report the crystal structures of TRIM7 in complex with 2C peptides of human enterovirus. Structure-guided studies reveal the C-terminal glutamine residue of 2C as the primary determinant for TRIM7 binding. Leveraged by this finding, we identify norovirus and SARS-CoV-2 proteins, and physiological proteins, as new TRIM7 substrates. Crystal structures of TRIM7 in complex with multiple peptides derived from SARS-CoV-2 proteins display the same glutamine-end recognition mode. Furthermore, TRIM7 could trigger the ubiquitination and degradation of these substrates, possibly representing a new Gln/C-degron pathway. Together, these findings unveil a common recognition mode by TRIM7, providing the foundation for further mechanistic characterization of antiviral and cellular functions of TRIM7.

Inhibition mechanisms of CRISPR-Cas9 by AcrIIA17 and AcrIIA18.

Mobile genetic elements such as phages and plasmids have evolved anti-CRISPR proteins (Acrs) to suppress CRISPR-Cas adaptive immune systems. Recently, several phage and non-phage derived Acrs including AcrIIA17 and AcrIIA18 have been reported to inhibit Cas9 through modulation of sgRNA. Here, we show that AcrIIA17 and AcrIIA18 inactivate Cas9 through distinct mechanisms. AcrIIA17 inhibits Cas9 activity through interference with Cas9-sgRNA binary complex formation. In contrast, AcrIIA18 induces the truncation of sgRNA in a Cas9-dependent manner, generating a shortened sgRNA incapable of triggering Cas9 activity. The crystal structure of AcrIIA18, combined with mutagenesis studies, reveals a crucial role of the N-terminal ß-hairpin in AcrIIA18 for sgRNA cleavage. The enzymatic inhibition mechanism of AcrIIA18 is different from those of the other reported type II Acrs. Our results add new insights into the mechanistic understanding of CRISPR-Cas9 inhibition by Acrs, and also provide valuable information in the designs of tools for conditional manipulation of CRISPR-Cas9.

Hemodiafiltration improves red blood cell lifespan in patients with end-stage renal disease.

INTRODUCTION: Uremic toxin-induced shortening of red blood cell (RBC) lifespan is an important mechanism of anemia in end-stage renal disease (ESRD). Conventional hemodialysis does not improve RBC lifespan; the efficacy of hemodiafiltration (HDF) for alleviating RBC lifespan has not yet been evaluated in patients with ESRD. METHODS: Twenty-three patients with ESRD in maintenance hemodialysis were enrolled. Baseline data for sex, age, dialysis vintage, pre-dialysis hemoglobin (Hb), blood urea nitrogen (BUN), intact parathyroid hormone (iPTH), single pool Kt/V (spKt/V), and plasma indophenol sulfate (IS) were collected. RBC lifespans before and after one session of HDF were compared. The resultant differences were subjected to correlational analyses with baseline data. RESULTS: RBC lifespan increased from 73 (66, 89) days at baseline to 77 (71, 102) days after a single HDF treatment (p = 0.034). Meanwhile, plasma IS concentration decreased from 113.05 (80.67, 133.05) mg/L to 83.87 (62.98, 96.78) mg/L (p < 0.001). RBC lifespan increases correlated negatively with Hb levels. CONCLUSIONS: A single HDF treatment improved RBC lifespan in ESRD patients on maintenance hemodialysis, with more severe pre-HDF anemia at baseline being associated with greater increases in RBC lifespan.

Comparison of Levitt's CO breath test and the 15 N-glycine labeling technique for measuring the lifespan of human red blood cells.

The red blood cell (RBC) lifespan is an important physiological indicator of clear significance in clinical research, used for the differential diagnosis of various diseases such as anemia, compensatory phase hemolysis, and polycythemia. The 15 N-glycine labeling technique is the gold standard method for determining RBC lifespans. However, the usefulness of this technique in clinical settings is seriously hindered by the several weeks required to complete the analyses. Levitt's CO breath test is another reliable technique for determining RBC lifespans, with a simpler protocol giving much faster results, making it more useful in clinical applications. We compared the CO breath test and 15 N-glycine labeling technique for measuring the human RBC lifespan. We investigated human RBC lifespans where each subject undertook both the 15 N-glycine labeling technique and the CO breath test. The correlation between the results from these two methods was analyzed. Eight of the ten subjects successfully completed the study. The RBC lifespan values obtained by Levitt's CO breath test were lower than those obtained by the 15 N-glycine labeling technique. The RBC lifespan values determined from the 15 N-glycine labeling technique and the CO breath test were significantly correlated, with a Pearson correlation coefficient of R = 0.98 (p < 0.05), while the R2 of the linear regression equation was 0.96. The CO breath test exhibits as good performance as the 15 N-glycine labelling technique in distinguishing healthy subjects from subjects with hemolysis. The result suggests that the CO breath test is a reliable method for quickly determining human RBC lifespans in clinical applications.

Possible two-photon absorption in the near-infrared region observed by cavity ring-down spectroscopy.

Two-photon absorption spectra are difficult to observe using direct absorption spectroscopy especially in the near-infrared region. Cavity ring-down spectroscopy is a promising absorption spectroscopy technique which has been widely applied to linear and saturated single-photon absorption spectra. In the present study, we report the observation of a possible two-photon absorption in the near-infrared using cavity ring-down spectroscopy, namely a two-photon resonance of methane. Using an optical frequency comb, the single-photon wavenumber of the double-quantum transition has been determined to be 182 207 682.645 MHz with a standard deviation of 75 kHz.

Red Blood Cell Lifespan Shortening in Patients with Early-Stage Chronic Kidney Disease.

BACKGROUND: Although reduced red blood cell (RBC) lifespan has been reported to be a contributory factor to anemia in patients with end-stage chronic kidney disease (CKD), there are limited data regarding RBC lifespan in early-stage CKD. Serum erythropoietin (EPO) is considered a primary causative factor of renal anemia. The aims of this study were to compare the RBC lifespan, serum EPO levels, and other renal anemia indicators across CKD-stage groups of patients and to analyze the impacts of etiological factors on renal anemia. METHODS: A cohort of 74 non-smoking patients with CKD were enrolled, including 15 in stage 1, 18 in stage 2, 15 in stage 3, 15 in stage 4, and 11 in stage 5. RBC lifespan was determined by CO breath tests. Potential correlations of hemoglobin (Hb) concentration with RBC lifespan, reticulocyte count (Ret), and levels of EPO, ferritin, folic acid, and vitamin B12 were analyzed. RESULTS: CKD progression was associated with decreases in (Hb) and RBC lifespan. RBC lifespan durations in CKD stages 1-5 were 122 ± 50, 112 ± 26, 90 ± 32, 88 ± 28, and 60 ± 24 days, respectively. RBC lifespan means for the stage 3, 4 and 5 groups were significantly shorter than those for the stage 1 and 2 groups. Serum EPO did not differ significantly between the CKD stage groups. (Hb) correlated directly with RBC lifespan (r = 0.372, p = 0.002) and Ret (r = 0.308, p = 0.011), but did not correlate with serum EPO, ferritin, folic acid, or vitamin B12 levels. CONCLUSIONS: Reduced RBC lifespan in early-stage CKD, demonstrated in this study, suggests that increased RBC destruction may play a more important etiological role in renal anemia than other indicators in patients with CKD.

[Determination of glyphosate in air of workplaces by ion chromatography].

OBJECTIVE: To establish a method for determining glyphosate in the air of workplaces by ion chromatography. METHODS: Ultra-fine glass fiber filter paper was used to collect glyphosate from the workplace air. After being ultrasonically eluted with deionized water, samples were determined by ion chromatography using a conductivity detector. RESULTS: Within the range of 0.05-1.00 mg/L, a linear relationship was found with a limit of detection of 0.003 mg/m(3). The minimum detectable concentration was 0.000 41 mg/m(3) (calculated by sampling 75 L of air). For three different concentrations of glyphosate, the intra-batch relative standard deviations (RSDs) were 1.8%, 1.6%, and 0.8%, respectively, and the inter-batch RSDs were 1.9%, 2.1%, and 2.2%, respectively. The recovery rate ranged from 94.8% to 97.4%. The elution efficiency ranged from 94.5% to 96.7%. The sampling efficiency was 100%. Samples could be stored at room temperature for at least 7 days. CONCLUSION: This presented method meets the requirements of Guide for establishing occupational health standards-Part 4: Determination methods of air chemicals in workplace and is feasible for determination of glyphosate in the air of workplaces.

Insights into the GSDMB-mediated cellular lysis and its targeting by IpaH7.8.

The multifunctional GSDMB protein is an important molecule in human immunity. The pyroptotic and bactericidal activity of GSDMB is a host response to infection by the bacterial pathogen Shigella flexneri, which employs the virulence effector IpaH7.8 to ubiquitinate and target GSDMB for proteasome-dependent degradation. Furthermore, IpaH7.8 selectively targets human but not mouse GSDMD, suggesting a non-canonical mechanism of substrate selection. Here, we report the crystal structure of GSDMB in complex with IpaH7.8. Together with biochemical and functional studies, we identify the potential membrane engagement sites of GSDMB, revealing general and unique features of gasdermin proteins in membrane recognition. We further illuminate how IpaH7.8 interacts with GSDMB, and delineate the mechanism by which IpaH7.8 ubiquitinates and suppresses GSDMB. Notably, guided by our structural model, we demonstrate that two residues in the α1-α2 loop make the mouse GSDMD invulnerable to IpaH7.8-mediated degradation. These findings provide insights into the versatile functions of GSDMB, which could open new avenues for therapeutic interventions for diseases, including cancers and bacterial infections.

Effect of roxadustat on red blood cell lifespan in patients with long-term haemodialysis: a single-centre, prospective, single-arm study.

Background: Reduced survival of red blood cells (RBCs) in patients with chronic kidney disease (CKD) is thought to contribute to renal anaemia. Although renal anaemia improved greatly because of the wide use of erythropoiesis-stimulating agents (ESAs) and the advancement of dialysis techniques, RBC longevity seems not to be obviously ameliorated. Methods: In this single-centre, single-arm trial, patients who had been undergoing haemodialysis and ESA therapy with epoetin alfa for at least 12 weeks changed their anti-anaemia drugs from epoetin alfa to oral roxadustat three times per week for 24 weeks. The primary endpoint was the change in RBC lifespan from baseline at week 24. The change in the circulating percentage of eryptotic RBCs, RBC deformability and RBC oxygen transport ability were also assessed. Results: A total of 27 patients were enrolled, with 26 completing the full course of intervention. At baseline, the average RBC lifespan was 60.1 days [standard deviation (SD) 14.4; n = 27]. At the end of the study period, 26 patients had an RBC lifespan measurement (83.9 days on average; SD 21.9). The RBC lifespan increased by 22.8 days on average [95% confidence interval (CI) 15.5-30.0, P < .001]. This equated to an average RBC lifespan increase of 39.2% (95% CI 27.8-50.6). The percentage of circulating eryptotic RBCs, erythrocyte filtration index and the pressure at which haemoglobin is 50% saturated decreased significantly from baseline to week 24 (1.39 ± 0.44% versus 0.89 ± 0.25%, P < .0001; 0.29 ± 0.12 versus 0.16 ± 0.08, P < .0001 and 32.54 ± 4.83 versus 28.40 ± 2.29, P < .001, respectively). Conclusion: Roxadustat prolonged RBC lifespan in patients with long-term haemodialysis.

Epigenetic integrity of paternal imprints enhances the developmental potential of androgenetic haploid embryonic stem cells.

The use of two inhibitors of Mek1/2 and Gsk3ß (2i) promotes the generation of mouse diploid and haploid embryonic stem cells (ESCs) from the inner cell mass of biparental and uniparental blastocysts, respectively. However, a system enabling long-term maintenance of imprints in ESCs has proven challenging. Here, we report that the use of a two-step a2i (alternative two inhibitors of Src and Gsk3ß, TSa2i) derivation/culture protocol results in the establishment of androgenetic haploid ESCs (AG-haESCs) with stable DNA methylation at paternal DMRs (differentially DNA methylated regions) up to passage 60 that can efficiently support generating mice upon oocyte injection. We also show coexistence of H3K9me3 marks and ZFP57 bindings with intact DMR methylations. Furthermore, we demonstrate that TSa2i-treated AG-haESCs are a heterogeneous cell population regarding paternal DMR methylation. Strikingly, AG-haESCs with late passages display increased paternal-DMR methylations and improved developmental potential compared to early-passage cells, in part through the enhanced proliferation of H19-DMR hypermethylated cells. Together, we establish AG-haESCs that can long-term maintain paternal imprints.

Red Blood Cell Lifespan < 74 Days Can Clinically Reduce Hb1Ac Levels in Type 2 Diabetes

Variations in the red blood cell (RBC) lifespan can affect glycosylated hemoglobin (HbA1c) test values, but there is still a lack of evidence regarding how and to what degree the RBC lifespan influences HbA1c in the type 2 diabetes mellitus (T2DM) population owing to the restriction of traditional RBC lifespan detection means. In this study, we monitored 464 T2DM patients and 231 healthy control finger blood glucose levels at seven time points for three consecutive months. The HbA1c levels were assessed at the end of the third month as well as the RBC lifespan was measured through the CO breath test. T2DM patients were stratified into four quartile groups according to their RBC lifespans. There was no statistical significance in HbA1c among these four groups. However, the average blood glucose in the Q1 group was significantly higher than those in the other groups. Additionally, the contribution of RBC lifespan to HbA1c test value in the Q1 group was 14.07%, which was significantly higher than those in the other groups. Finally, we used multiple linear regression models to construct a mathematical formula to correct the HbA1c test value in the Q1 group, which would benefit the management of T2DM.

Intranasal budesonide for rhinitis during a high airborne pollution period: a randomized controlled trial.

BACKGROUND: Air pollution may induce or reinforce nasal inflammation regardless of allergy status. There is limited direct clinical evidence informing the treatment of airborne pollution-related rhinitis. OBJECTIVE: To assess the effectiveness of intranasal budesonide in adults with self-reported rhinitis symptoms triggered/worsened by airborne pollution. METHODS: Adults in northern China with self-reported rhinitis symptoms triggered or worsened by airborne pollution were randomized to budesonide 256 µg/day or placebo for 10 days in pollution season (October 2019 to February 2020). The primary endpoint was the mean change from baseline in 24-h reflective total nasal symptom score (rTNSS) averaged over 10 days. The secondary endpoints were subject-assessed Global Impression of Change (SGIC), mean change from baseline in individual nasal symptom severity, and mean change from baseline in individual non-nasal symptoms of cough and postnasal drip severity. One-sided P < 0.0125 was considered statistically significant. RESULTS: After an interruption by COVID-19, an interim analysis showed that the study could be ended for efficacy with n = 206 participants (103/group) since the primary efficacy endpoint demonstrated significant results. The final efficacy results showed that the 10-day-averaged rTNSS change in the budesonide group was greater than with placebo (- 2.20 vs - 1.72, P = 0.0107). Budesonide also significantly improved 10-day-averaged itching/sneezing change (- 0.75 vs - 0.51, P = 0.0009). Results for SGIC and all other individual symptoms did not show significant differences between the two groups. CONCLUSIONS: Intranasal budesonide 256 µg once daily improved the total nasal symptoms and itching/sneezing over 10 days in adults with rhinitis triggered/worsened by airborne pollution.

High-Photoresponsivity Self-Powered a-, ε-, and ß-Ga2O3/p-GaN Heterojunction UV Photodetectors with an In Situ GaON Layer by MOCVD.

In this paper, self-powered ultraviolet (UV) photodetectors with high response performance based on Ga2O3/p-GaN were fabricated by metal-organic chemical vapor deposition (MOCVD). The effects of different crystal phases of Ga2O3 (including a, ε, ε/ß, and ß) grown on p-GaN films on the performance of photodetectors were systematically studied. Moreover, an in situ GaON dielectric layer improved the responsivity of Ga2O3/p-GaN photodetectors by 20 times. All Ga2O3/p-GaN photodetectors showed self-power capability without bias. An ultralow dark current of 3.08 pA and a Iphoto/Idark ratio of 4.1 × 103 (1.8 × 103) under 254 nm (365 nm) light were obtained for the ß-Ga2O3/p-GaN photodetector at 0 V bias. Furthermore, the ß-Ga2O3/p-GaN photodetector showed excellent sensitivity with a high responsivity of 3.8 A/W (0.83 A/W), a fast response speed of 66/36 ms (36/73 ms), and a high detectivity of 1.12 × 1014 Jones (2.44 × 1013 Jones) under 254 nm (365 nm) light at 0 V bias. The carrier transport mechanism of the Ga2O3/p-GaN self-powered photodetector was also analyzed through the device energy band diagram. This work provides critical information for the design and fabrication of high-performance self-powered Ga2O3/p-GaN UV photodetectors, opening the door to a variety of photonic systems and applications without an external power supply.

Levitt's CO breath test in the differential diagnosis of chronic isolated hyperbilirubinemia.

A key component of the differential diagnosis of isolated hyperbilirubinemia (HB) is distinguishing between hemolytic and non-hemolytic types. Routine hemolysis screening markers have unsatisfactory sensitivity and specificity. Erythrocyte (RBC) lifespan shortening, the gold standard marker of hemolysis, is seldomly measured due to the cumbersome and protracted nature of standard methods. A new Levitt's CO breath test method may enable simple, rapid RBC lifespan measurement. In this pilot prospective diagnostic study, Levitt's CO breath test was evaluated to discriminate hemolytic from non-hemolytic HB in adults. One hundred and thirty eligible non-smoking adult patients who were aged 18 or older, referred for chronic (>6 months) isolated HB or had a known diagnosis of isolated HB of a rare cause, were recruited, including 77 with non-hemolytic HB and 53 with hemolytic HB. ROC curve analysis was applied to determine the optimal cutoff for discriminating between hemolytic and non-hemolytic HB, and the performance was calculated. Results showed that the mean RBC lifespan in non-hemolytic HB (93 ± 26 d) was reduced (p= 0.001 vs. normal reference value of 126 d), but longer than that in hemolytic HB (36 ± 17 d;p= 0.001). RBC lifespans did not differ significantly between 26 patients with simple hemolytic HB (32 ± 14 d) and 27 patients with a Gilbert syndrome comorbidity (40 ± 18 d). ROC curve analysis revealed an optimal lifespan cutoff for discriminating between hemolytic and non-hemolytic HB of 60 d (AUC = 0.982), with a diagnostic accuracy of 95.4%, 94.3% sensitivity and 96.1% specificity respectively. These results indicate that Levitt's CO breath test seems to be very sensitive and specific for detecting hemolysis in adult patients with chronic isolated HB, and could enable simple, rapid, and reliable differential diagnosis of isolated HB. A large-scale validation study of the method is warranted.

[Resident dietary exposure of cadmium in Jiangsu province].

OBJECTIVE: To investigate the resident dietary cadmium exposure in Jiangsu province and assess its safety. METHODS: Cadmium concentration of 229 food items under 12 food groups were obtained from the food surveillance program in Jiangsu province between 2001 and 2006. Food consumption data of 778 food items of 3938 residents who were classified into four age groups (< 7, 7-, 13-, 18-) were got from the Nutrition and Health Status Survey of the Jiangsu resident in 2002 by 24 h dietary recall on three consecutive days. Dietary cadmium exposures for the residents of different age groups were obtained by using both point estimation and simple distribution estimation through integrating the two datasets above. The safety of dietary cadmium exposure was assessed. RESULTS: Point estimation showed that the average dietary cadmium intakes of different age groups ranged from 5.7 to 8.6 microg/kg, accounting for 567.1% - 857.1% of the provisional tolerable daily intake (PTDI, 1.0 microg/kg). Result of simple distribution method showed mean daily cadmium exposure of different age groups ranged from 0.2 to 0.4 microg/kg, accounting for 20% - 40% of PTDI. Mean weekly cadmium exposure ranged from 1.4 to 2.5 microg/kg, accounting for 20% - 35.7% of the provisional tolerable weekly intake (PTWI, 7.0 microg/kg). The mean daily dietary cadmium exposure for different groups were as follows: < 7, 0.4 microg/kg; 7-, 0.3 microg/kg; 13-, 0.2 microg/kg; 18-, 0.2 microg/kg. Differences of daily dietary cadmium exposures among groups were significant (F = 69.0, P < 0.05). The mean weekly dietary cadmium exposure for different groups were: < 7, 2.5 microg/kg; 7-, 2.0 microg/kg; 13-, 1.4 microg/kg; 18-, 1.4 microg/kg. Differences of weekly dietary cadmium exposures among groups were also significant (F = 41.6, P < 0.05). The P97.5 of daily cadmium exposure for < 7 and 7- were 1.4 and 1.2 microg/kg, respectively, both of which were higher than PTDI. The P99.0 of daily cadmium exposure for 13- and 18- were 1.3 and 1.1 microg/kg, respectively. The daily dietary exposure from cereals for different age groups were 21.5 - 253.4 microg/kg, occupying 42.2% - 47.8% of the total daily exposure. Vegetables were 8.0 - 119.4 microg/kg, occupying 14.6% - 20.1%. CONCLUSION: The average level of dietary cadmium exposures for residents in Jiangsu province calculated by simple distribution estimation were much lower than that calculated by point estimation and were considered to be at no risk. P97.5 or P99.0 of daily or weekly dietary cadmium exposure of different age groups exceeded PTWI and PTDI. The main food types of dietary cadmium exposure were cereals and vegetables.

[Development and verification of Chinese dietary exposure evaluation model software].

OBJECTIVE: To develop the dietary exposure evaluation model software accredited of Chinese intellectual property rights and to verify the rationality and accuracy of the results from the probabilistic model in Chinese dietary exposure evaluation model software according to international standards. METHODS: The software of SAS was used to build various evaluation model based on the data from Chinese dietary survey and the chemical compound in food surveillance and to design an operation interface. The results from probabilistic dietary exposure model for children 2 - 7 years old were compared with that from duplicate portion study of 2-7 years children dietary exposure in Jinhu, Jiangsu province in order to analyze the rationality of model. The results from probabilistic model of dietary exposure were compared with the results from @Risk software to verify the correction of the probabilistic model by using the same data of randomly selected 10 000 study subjects from national dietary survey. While, the mean drift was used as an internal index to illustrate the accuracy of the computation. RESULTS: Chinese dietary exposure evaluation software was developed successfully. On the rationality, the results from probabilistic model were lower than that from the point estimation (e.g., cucumber: the result of point estimation of acephate was 4.78 microg x kg(-1) x d(-1), while the results of probabilistic model which was 0.39 microg x kg(-1) x d(-1)). Meanwhile the results from probabilistic model were higher than the results of duplicate portion study (on the P95, the result of probabilistic model of Pb exposure in children was 11.08 microg x kg(-1) x d(-1), while the results of duplicate portion study was 5.75 microg x kg(-1) x d(-1)). On accuracy, the results from @Risk and the probabilistic model were highly consistent (on the P95, the result of probabilistic assessment of acephate diet exposure was 4.27 microg x kg(-1) x d(-1), while the results of duplicate portion study was 4.24 microg x kg(-1) x d(-1)), and the mean drift was of random distribution, the drift region varied from 0.05% to 11.9%. CONCLUSION: The results computed by the software of Chinese dietary exposure evaluation model are reliable and reasonable, which is a meaningful step to improve the dietary exposure evaluation technique in China.

A pilot study: effect of erythrocyte lifespan determined by a modified carbon monoxide breath test on glycosylated hemoglobin interpretation.

Glycosylated hemoglobin (HbA1c) is an important criterion for the diagnosis of diabetes and an indicator of the blood glucose level. The red blood cell (RBC) lifespan heterogeneity is sufficient to influence the HbA1c interpretation. In this study, we recruited 120 patients with diabetes mellitus and 85 nondiabetic controls. The HbA1c and the RBC lifespan were detected by high-performance liquid chromatography and the advanced carbon monoxide breath detection method, respectively. Potential correlations of gender and age with HbA1c were analyzed and a receiver operator characteristic curve was generated to get the HbA1c cut-off for every RBC lifespan group. It was confirmed that HbA1c has no correlation with gender or age. The correlation formula between the HbA1c diagnostic criteria and RBC lifespan was derived to correct the HbA1c diagnostic criteria using the least-square method. The RBC-lifespan-corrected HbA1c diagnostic criteria provided 100% sensitivity and specificity for the diagnosis of diabetes in the experimental set and was not refuted in the validated set. The diagnostic value of HbA1c is positively correlated with the RBC lifespan, and four patients with hyperglycemia, whose HbA1c values were lower than the general diagnosis criterion of 6.5%, were still considered to be diabetic according to this formula; that is, the application of this formula may help us to eliminate the 2.2% misdiagnosis rate of the current diagnostic criteria. To provide more accurate detection results, the effect of the RBC lifespan needs to be taken into account when HbA1c is used as a clinical indicator.

Carbon monoxide breath test assessment of mild hemolysis in Gilbert's syndrome.

BACKGROUND: Mild hemolysis is difficult to determinate by traditional methods, and its role in Gilbert's syndrome (GS) is unclear. The main aims were to inspect the erythrocyte (RBC) survival in GS by using Levitt's carbon monoxide (CO) breath test and to assess its contribution to unconjugated hyperbilirubinemia. METHODS: Fifty subjects with GS and 1 with type-II Crigler-Najjar syndrome (CN2) received RBC lifespan measurement with Levitt's CO breath test. Mean RBC lifespan was compared with normal referral value. Correlations of serum total bilirubin (TB) with RBC lifespan, blood panel data, demographic factors, and uridine diphosphate glucuronosyltransferase (UGT1A1) mutation load were calculated by Spearman analysis. Susceptibility factors for mild hemolysis were analyzed by multivariate regression analysis. RESULTS: The mean RBC lifespan of the GS subjects was significantly shorter than the normal reference value (95.4 ±â€Š28.9 days vs 126 days; t = -7.504, P < .01), with 30.0% below the lower limit of the normal reference range (75 days). The RBC lifespan of the participant with CN2 was 82 days. Serum TB correlated positively with UGT1A1 mutation load (γ = 0.281, P = .048), hemoglobin (γ = .359, P = .010) and hematocrit (γ = 0.365, P = .010), but negatively with RBC lifespan (γ = -0.336, P = .017). No significant susceptibility factors for mild hemolysis were found. CONCLUSIONS: The results indicate that mild hemolysis indeed, exists in a portion of patients with GS and might serve as an important contributor to unconjugated hyperbilirubinemia in addition to UGT1A1 polymorphism. Further studies on the mechanism and the potential risks in various medical treatments might be wanted.

Fructan from Polygonatum cyrtonema Hua as an eco-friendly corrosion inhibitor for mild steel in HCl media.

An effective and biodegradable polygonatum fructan (PF) from Polygonatum cyrtonema Hua was studied as an eco-friendly corrosion inhibitor for mild steel protection in 1 M HCl, whose inhibition performance was studied by weight loss tests, electrochemical techniques, and surface analysis techniques (SECM, FTIR). The experimental results showed that PF has outstanding inhibition performance for mild steel in hydrochloric acid, and the inhibition efficiency increased with the increase of its concentration and temperature. Polarization studies indicated that PF is a mixed-type corrosion inhibitor, and its adsorption mode conforms to Langmuir isotherm, mainly chemisorption. An adsorption-related protective inhibitor film formed on the surface of mild steel was verified and investigated based on its surface analysis and characterization. Quantum chemical analysis showed that the adsorption of PF on the surface of mild steel has obvious chemical properties.