Coronary microvascular dysfunction: prevalence and aetiology in patients with suspected myocardial ischaemia

AIM

To evaluate the prevalence, aetiology, and corresponding morbidity of coronary microvascular dysfunction (CMD) in patients with suspected myocardial ischaemia.

MATERIALS AND METHODS

The present study included 115 patients with suspected myocardial ischaemia who underwent stress perfusion cardiac magnetic resonance imaging. CMD was assessed visually based on the myocardial perfusion results. The CMR-derived myocardial perfusion reserve index (MPRI) and left ventricular (LV) strain parameters obtained using the post-processing software CVI42 were employed to evaluate LV myocardial perfusion and deformation. LV strain parameters included global longitudinal, circumferential, and radial strain (GLS, GCS, and GRS), global systolic/diastolic longitudinal, circumferential, and radial strain rates (SLSR, SCSR, SRSR, DLSR, DCSR, and DRSR).

RESULTS

Of the 115 patients, 12 patients were excluded and 103 patients were finally included in the study. CMD was observed in 79 % (81 patients, aged 53 ± 12 years) of patients. Regarding aetiology, 91 (88 %) patients had non-obstructive coronary artery disease (CAD), eight (8 %) had obstructive CAD, and four (4 %) had hypertrophic cardiomyopathy (HCM). The incidence of CMD was highest (100 %) in patients with HCM, followed by those with non-obstructive CAD (up to 79 %). There were no statistical differences between CMD and non-CMD groups in GCS, GRS, GLS, SRSR, SCSR, SLSR, DCSR, DRSR and DLSR.

CONCLUSION

The incidence of CMD was higher in patients with signs and symptoms of ischaemia. CMD occurred with non-obstructive CAD, obstructive CAD, and HCM, with the highest prevalence of CMD in HCM.

Expression of chicken epidermal growth factor (cEGF) in Escherichia coli regulates the microflora structure of the duodenum to improve growth performance and intestinal morphogenesis in broilers

1. A study used gene synthesis to obtain the functional domains of chicken epidermal growth factor (cEGF) and examined their impact on broiler growth performance, small intestinal morphology, digestive enzyme activities in the intestinal contents and the structure of duodenal microflora.2. The pET-32a-cEGF recombinant expression vector was constructed. The specific band at 26 KDa was shown by SDS-PAGE analysis and WB results. The purified protein content was shown to be 1687 μg/ml by assay.3. A total of 180 healthy, one-day-old Arbor Acres male, white-feathered broilers were randomly divided into three dietary treatment groups (six replicate pens, 10 birds per replicate): A control diet (ND); cEGF diet (cEGF), control supplemented with 250 mg/kg cEGF and the control diet (CD) supplemented with 250 mg/kg chlortetracycline.4. The results showed that feeding the cEGF and CD diet reduced FCR of broilers aged 1-21 d, average daily feed intake (ADFI) at 22-42 d, and the FCR in the whole period (1-42 d; p < 0.05). Compared with the ND group, the cEGF diet increased duodenal α-amylase and alkaline phosphatase activities in the 1-21 d, duodenal lipase, alkaline phosphatase, and ileal alkaline phosphatase activities in the post-period and increased villus height in the duodenum and ileum (p < 0.05). In addition, the ACE and Chao1 index for the birds fed cEGF were higher than the ND group (p < 0.05). At the phyla level, Firmicutes and Proteobacteria were dominant in all groups. At the genus level, the dominant genus was Lactobacillus. The LEfSe analysis showed that the cEGF group was enriched by 11 species including Brevibacillus, Eisenbergiella, Cloacibacterium, Butyricoccus spp.5. The addition of 250 mg/kg cEGF to the diet can increase growth performance by improving intestinal development and digestive enzyme activity, which may be related to the duodenal intestinal microflora. Therefore, cEGF is an effective alternative to antibiotics in broiler farming.

Achromobacter species (sp.) outbreak caused by hospital equipment containing contaminated water: risk factors for infection

BACKGROUND

Nosocomial outbreaks of urinary tract infections caused by Achromobacter spp. have been rare in recent decades.

AIM

To identify the origin of an Achromobacter sp. outbreak, conduct multi-modal infection control measures, and finally to stop the outbreak. To this end, an epidemiological outbreak investigation and risk factor analysis were performed.

METHODS

Achromobacter sp. was detected in 22 patients in our urology wards and six environmental cultures of specimens obtained from the operating rooms. Strains isolated were submitted for antimicrobial susceptibility testing. An on-site epidemiological investigation, evaluation of patient medical records, and environmental sampling were performed to identify the source of the outbreak, and implementation of infection control intervention. A case-control study was performed to analyse the potential risk factors.

FINDINGS

Environmental sampling showed that the source of the infection for 22 patients was an ISA-IIIA-type medical pressurizer containing contaminated water. A case-control analysis showed that the risk factors for infection were: diagnosis of kidney/ureteral stones, surgery, placement of a double-J stent, and history of hospitalization in the past three months.

CONCLUSION

It was concluded that the outbreak occurred in patients who underwent internal lithotripsy and double-J stent placement, due to contact transmission with the contaminated sensor and connecting tubes of the ISA-IIIA-type medical pressurizer.

Intervention model under the Omaha system framework can effectively improve the sleep quality and negative emotion of patients with mid to late-stage lung cancer and is a protective factor for quality of life

This study aims to evaluate the effects of Omaha System framework interventions on quality of life, emotional well-being, and sleep quality in 507 mid to late-stage lung cancer patients. Retrospectively, we compared data of 294 patients receiving conventional care (conventional group) with 213 patients undergoing Omaha System interventions (intervention group) from January 2019 to January 2023. Key indicators included quality of life (FACT-L), anxiety (SAS), depression (SDS), sleep quality (PSQI), hope (HHS), and dignity (PDI). Post-intervention, the intervention group showed a significant increase in FACT-L scores (P<0.001), indicating enhanced quality of life. There was a notable reduction in PSQI scores (P<0.001), suggesting improved sleep quality. Additionally, their anxiety and depression levels significantly decreased, as evidenced by lower SAS (P<0.001) and SDS scores (P<0.001). Logistic regression revealed that care nursing intervention scheme (P=0.007), age (P=0.008), marital status (P=0.002), per capita monthly household income (P=0.004), SAS after intervention (P=0.002), and PSQI after intervention (P=0.002) had a positive influence on quality of life. In conclusion, the Omaha System interventions markedly improved the quality of life, emotional state, and sleep in lung cancer patients.

Relationship between coronary microvascular dysfunction (CMD) and left ventricular diastolic function in patients with symptoms of myocardial ischemia with non-obstructive coronary artery disease (INOCA) by cardiovascular magnetic resonance feature-tracking

AIM

To investigate whether there was an association between coronary microvascular dysfunction (CMD) and left ventricular (LV) diastolic function in patients with myocardial ischemia with non-obstructive coronary artery disease (INOCA).

MATERIALS AND METHODS

Our study included 115 subjects with suspected myocardial ischemia that underwent stress perfusion cardiac magnetic resonance (CMR). They were divided into non-CMD and CMD two groups. CMR-derived volume-time curves and CMR-FT parameters were used to assess LV diastolic function using CVI42 software. The latter included global/regional LV peak longitudinal, circumferential, radial diastolic strain rate (LDSR, CDSR, RDSR). Logistic regression analysis was performed with CMR-FT strain parameters as independent variables and CMD as dependent variables, and the effect value was expressed as an odds ratio (OR).

RESULTS

Of the 115 patients, we excluded data from 23 patients and 92 patients (56.5% male；52 ± 12 years) were finally included in the study. Of these, 19 patients were included in the non-CMD group (49 ± 11 years) and CMD group included 73patient (52 ± 12 years). The regional CDSR (P=0.019), and regional RDSR (P=0.006) were significantly lower in the CMD group than in non-CMD group. But, regional LDSR in CMD group was higher than non-CMD (P=0.003). In logistic regression analysis, regional LDSR (adjusted β= 0.1, 95%CI 0.077, 0.349, p=0.002) and RDSR (adjusted β= 0.1, 95 % CI 0.066, 0.356, p=0.004) were related to CMD.

CONCLUSIONS

LV myocardial perfusion parameter MPRI was negatively correlated with LV diastolic function (CDSR) which needs to take into account the degree of diastolic dysfunction.

[Research progress and prospects of artificial intelligence in diagnosis and treatment of colorectal cancer]

Colorectal cancer is one of the most common malignant tumors worldwide. Due to the heterogeneity in patient outcomes and treatment responses to standard therapy regimens, personalized diagnostic and therapeutic strategies have remained a focus of sustained interest in research. In recent years, with the rapid progression of artificial intelligence (AI) technology in the medical field, an abundance of phased research results has emerged in the decision-making for preoperative, intraoperative, and postoperative diagnostic and therapeutic plans for colorectal cancer, demonstrating great potential for application. This new and efficient solution provides for the personalized evaluations and auxiliary diagnoses and treatments of patients with colorectal cancer. In the future, AI systems may continue to advance towards multimodal, multi-omics, and real-time directions. This paper aims to explore the current state of research on the multi-faceted auxiliary applications of AI in the diagnosis and treatment of colorectal cancer, as well as to present a prospective view of the innovations that AI technology could bring to personalized colorectal cancer treatment in the future and the challenges it may face.

Piezoelectric polarization induced by dual piezoelectric materials ZnO nanosheets/MoS2 heterostructure for enhancing photoelectrochemical water splitting

Zinc oxide (ZnO) has a broad range of applications in piezo-photoelectrochemical water splitting. However, the narrow light absorption range and high photogenerated carrier recombination efficiency make ZnO somewhat limited in applying piezo-photoelectrochemical water splitting. Heterogeneous structure construction is a superior handle to these two drawbacks. Herein, few-layer molybdenum disulfide (MoS2) nanospheres are compounded on ZnO nanosheets (NSs) to form a dual-piezoelectric-material heterojunction of ZnO NSs/MoS2. The photocurrent density of ZnO NSs/MoS2 reaches 0.68 mA/cm2 at 1.23 V vs. RHE under ultrasonic vibrations. It is 2.4 times higher than that of ZnO NSs under ultrasonic vibrations. The efficient piezo-photoelectrochemical performance is attributed to increased absorption range and polarization field. On the one hand, the narrow band gap of the few-layer MoS2 widens the light absorption range of ZnO. On the other hand, compared to pure ZnO NSs, ZnO NSs/MoS2 has an enhanced polarization field under ultrasonic vibrations due to the piezoelectric properties of dual piezoelectric materials, which dramatically accelerates the electron transfer and suppresses the recombination of between electrons and holes. This work provides a new approach to constructing photoelectrodes with effective piezoelectric photocatalytic properties.

[Analysis of clinical characteristics and treatment status of atopic dermatitis in a children's hospital in Beijing from 2015 to 2019]

To analyze the clinical characteristics and treatment status of atopic dermatitis (AD) in children in the outpatient department of a children's hospital in Beijing from 2015 to 2019. This study used a cross-sectional study method to retrospectively analyze the data of AD patients who visited the Dermatology outpatient department of Beijing Children's Hospital, Capital Medical University, from April 2015 to April 2019. A total of 1 926 AD patients aged 0-17.5 years old living in Beijing and its surrounding areas were included, and the general situation, severity and distribution of AD disease, clinical characteristics and severity of AD, relevant influencing factors of AD onset, AD disease prognosis and treatment status were recorded. SAS 9.4, SPSS19.0, and R software were used for data processing, and descriptive statistical analysis, Chi-square test, Analysis of Variance, and correspondence analysis were used for statistical analysis. The results showed that the male to female ratio of AD patients in children included in this study was 1.4∶1; 79.0% (1 522/1 926), 86.1%(1 658/1 926), 91.3%(1 758/1 926), and 97.3%(1 907/1 926) of AD onset at the age of 6 months, 1 year, 2 years, and 5 years, respectively; mild of AD patients accounted for 13.2% (255/1 926)(SCORAD score 0-24), moderate of AD patients accounted for 50.1%(965/1 926) (SCORAD score 25-50), and severe of AD patients accounted for 36.7% (706/1 926)(SCORAD score>50).The age of severe AD patients were younger than mild and moderate AD patients. The face, head, trunk, and lower limbs were common areas of onset for moderate to severe AD, while the hands, feet, and ears were common areas of onset for severe AD patients. Temperature changes, hot water factors, mental and emotional states, and spring and winter were the main aggravation factors of AD;35.2% (678/1 926) aggravated and 61.8% (1 191/1 926) persistent. The more frequent bathing, the less severity of AD disease (χ2=29.791,P<0.001); 28.0% (520/1 856) of AD patients have no moisturizing habits, which were correlated with the severity of AD disease (χ2=15.908, P<0.05); the proportion of combined treatment medications in children with moderate to severe AD was significantly higher than mild AD patients. In conclusion, the patients with AD who went to specialist clinics were mainly moderate to severe patients and developed disease before the age of 5 years from 2015 to 2019.The severity of AD were mainly moderate to severe, and most of these patients had poor disease control. Traditional treatment plans had limitations. Identifying the clinical characteristics and treatment status of childhood AD would help us to carry out more targeted prevention and management work.

Lin- PU.1dim GATA-1- defines haematopoietic stem cells with long-term multilineage reconstitution activity

Despite extensive characterization of the state and function of haematopoietic stem cells (HSCs), the use of transcription factors to define the HSC population is still limited. We show here that the HSC population in mouse bone marrow can be defined by the distinct expression levels of Spi1 and Gata1. By using a double fluorescence knock-in mouse model, PGdKI, in which the expression levels of PU.1 and GATA-1 are indicated by the expression of GFP and mCherry, respectively, we uncover that the HSCs with lymphoid and myeloid repopulating activity are specifically enriched in a Lin- PU.1dim GATA-1- (LPG) cell subset. In vivo competitive repopulation assays demonstrate that bone marrow cells gated by LPG exhibit haematopoietic reconstitution activity which is comparable to that of classical Lin- Sca1+ c-kit+ (LSK). The integrated analysis of single-cell RNA sequence data from LPG and LSK-gated cells reveals that a transcriptional network governed by core TFs contributes to regulation of HSC multipotency. These discoveries provide new clues for HSC characterization and functional study.

[Hsa_circ_0000392 affects the radiation sensitivity of cervical cancer by targeting the miR-145-5p/CRKL/MAPK pathway]

Objective: To investigate the effect of hsa_circ_0000392 (circ_0000392) on the radiosensitivity of cervical cancer cells and explore its potential mechanism. Methods: Cervical cancer tissues and adjacent normal tissues of 42 patients with cervical cancer who were confirmed pathologically for the first time in Huaihe Hospital of Henan University from 2016 to 2019 were collected. According to the patients' response to radiotherapy, the cancer tissues were divided into radio-sensitive tissues and radio-resistant tissues. The expressions of circ_0000392, miR-145-5p, and CRKL in radiation-sensitive, radiation-resistant cervical cancer tissues and Hela, SiHa cells were detected by reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and western blot. SiRNA circ_0000392, miR-145-5p mimic, miR-145-5p inhibitor, pcDNA 3.1-CRKL and its negative control were transfected into HeLa and Siha cells, respectively. After radiation induction, the survival fraction of cells was detected by clone formation assay, apoptosis was detected by flow cytometry, and the expressions of apoptosis-related proteins Bax and Bcl-2 and ERK pathway protein p-ERK1/2 and ERK1/2 were detected by western blot. The targeting relationship between circ_0000392, miR-145-5p and CRKL was verified by dual luciferase reporter gene assay. The effect of circ_0000392 on radiotherapy sensitivity of cervical cancer in vivo was observed in the tumor formation experiment in nude mice. Results: circ_0000392 and CRKL were upregulated in radiation-resistant tissues and cancer cells of cervical cancer, while miR-145-5p was downregulated. The clone formation numbers of Hela and SiHa cells in si-circ_0000392#1+ 6 Gy group were (78.67±10.97) and (71.00±9.54), respectively, which were lower than those in si-Ctrl+ 6 Gy group [(176.00±22.27) and (158.33±17.56), respectively]. The apoptosis rates were (41.55±3.40)% and (31.41±3.29)%, respectively, which were higher than those in si-Ctrl+ 6 Gy group [(15.91±1.37)% and (13.70±1.89)%, P<0.05]. The protein expression of Bax was higher than that of si-Ctrl+ 6 Gy group, and the protein expressions of Bcl2 was lower than those of si-Ctrl+ 6 Gy group. The clone formation numbers of Hela and SiHa cells in si-circ_0000392#1+ miR-145-5p inhibitor+ 6 Gy group were (171.33±25.01) and (137.00±21.66), higher than those in si-circ_0000392#1+ inhibitor NC+ 6 Gy group [(84.67±17.79) vs (71.00±11.00), P<0.05]. The apoptosis rates were (17.41±2.58) % and (15.96±1.25) %, lower than those of si-circ_0000392 #1+ inhibitor NC+ 6 Gy [(40.29±2.92)% and (30.82±2.34)%, respectively, P<0.05]. The expression of Bax protein was lower than that of si-circ_0000392#1+ inhibitor NC+ 6 Gy group, and the expressions of Bcl2 protein were higher than those of si-circ_0000392#1+ inhibitor NC+ 6 Gy group. Circ_0000392 can target miR-145-5p, and CRKL is the downstream target gene of miR-145-5p. The clone formation numbers of Hela and SiHa cells in miR-145-5p mimic+ 6 Gy group were (74.33±10.02) and (66.00±12.17), respectively, which were lower than those of mimic NC+ 6 Gy group [(197.67±17.21) vs (157.67±11.59), respectively, P<0.05]. The apoptosis rates were (45.58±2.16)% and (32.10±3.55)%, higher than those of mimic NC+ 6 Gy group [(15.85±2.45)% and (13.99±1.69)%, respectively, P<0.05]. The expression of Bax protein was higher than that of the mimic NC+ 6 Gy mimic group, and the expression of Bcl2 protein was lower than that of the mimic NC+ 6 Gy group. The clone formation numbers of Hela and SiHa cells in miR-145-5p mimic+ pcDNA-CRKL+ 6 Gy group were (158.00±15.88) and (122.33±13.65), respectively, which were higher than those of miR-145-5p mimic+ pcDNA+ 6 Gy group [(71.33±8.02) vs (65.67±12.22), P<0.05]. The apoptosis rates were (19.50±3.45)% and (17.04±0.94)%, respectively, which were lower than those of miR-145-5p mimic+ pcDNA+ 6 Gy group [(44.33±2.36)% and (32.05±2.76)%, respectively, P<0.05]. The expression of Bax protein was lower than that of miR-145-5p mimic+ pcDNA group+ 6 Gy group, and the expression of Bcl2 protein was higher than that of miR-145-5p mimic+ pcDNA+ 6 Gy group. Sh-circ_0000392 group had smaller tumor volume and decreased tumor weight (P<0.05). The relative mRNA expression levels of circ_0000392, miR-145-5p and CRKL and the relative protein expression levels of CRKL, Bcl-2 and p-ERK1/2 were decreased, while the relative expression level of Bax protein was increased (P<0.05). Conclusion: Circ_0000392 could enhance the radiosensitivity of cervical cancer cells, and its mechanism may be related to the regulation of CRKL/ERK signaling pathway by targeting miR-145-5p, which provides a new reference for enhancing the radiosensitivity of cervical cancer cells.

Temporal Structures in Positron Spectra and Charge-Sign Effects in Galactic Cosmic Rays

We present the precision measurements of 11 years of daily cosmic positron fluxes in the rigidity range from 1.00 to 41.9 GV based on 3.4×10^{6} positrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The positron fluxes show distinctly different time variations from the electron fluxes at short and long timescales. A hysteresis between the electron fluxes and the positron fluxes is observed with a significance greater than 5σ at rigidities below 8.5 GV. On the contrary, the positron fluxes and the proton fluxes show similar time variation. Remarkably, we found that positron fluxes are modulated more than proton fluxes with a significance greater than 5σ for rigidities below 7 GV. These continuous daily positron fluxes, together with AMS daily electron, proton, and helium fluxes over an 11-year solar cycle, provide unique input to the understanding of both the charge-sign and mass dependencies of cosmic rays in the heliosphere.

[Poisonous substances and geographical distribution of poisoning in hospitalized children based on data from 25 hospitals in China from 2016 to 2020]

Objective: To investigate the poisonous substances and geographical distribution of poisoning in children in China. Methods: A cross-sectional study. The clinical data of 8 385 hospitalized children from January 2016 to December 2020 were extracted from the FUTang Updating Medical Records database. These children aged 0 to 18 years and were admitted due to poisoning. They were grouped according to age (newborns and infants, toddlers, preschoolers, school-age children, adolescents), place of residence (Northeast China, North China, Central China, East China, South China, Southwest China, Northwest China), and mode of discharge (discharge under medical advice, transfer to another hospital under medical advice, discharge without medical advice, death, other). The poisonous substance and causes of poisoning in different groups were analyzed. Results: Among these 8 385 children, 4 734 (56.5%) were male and 3 651 (43.5%) female, with a male-to-female ratio of 1.3∶1. The age was 3 (2, 7) years. The prevalence of poisoning was 51.8% (4 343/8 385) in toddlers, 16.5% (1 380/8 385) in adolescents, 14.8% (1 242/8 385) in preschoolers, 14.4% (1 206/8 385) in school-age children, and 2.5% (214/8 385) in newborns and infants. Drug poisoning accounted for 43.5% (3 649/8 385) and pesticide accounted for 26.8% (2 249/8 385). Drug poisoning was more common in adolescents (684/1 380, 49.6%) and toddlers (2 041/4 343, 47.0%); non-drug poisoning was more common in school-age children (891/1 206, 73.9%), of which carbon monoxide was mainly in newborns and infants (41/214, 19.2%) and food poisoning in children of school age (241/1 206, 20.0%). Regarding regional characteristics, drug poisoning was more frequent in South China (188/246, 64.2%) and non-drug poisoning was more frequent in Southwest China (815/1 123, 72.5%). For drugs, anti-epileptic drugs, sedative-hypnotic drugs and anti-Parkinson's disease drugs had a higher proportion of poisoning in North China (138/1 034, 13.0%) than that in other regions. For non-drug poisoning, pesticides (375/1 123, 33.3%), food poisoning (209/1 123, 18.6%) and contact with poisonous animals (86/1 123, 7.7%) were more common in Southwest China than in other regions; carbon monoxide poisoning was more common in North China (81/1 034, 7.6%) and Northwest China (65/1 064, 6.3%). In Central China, poisoning happened more in toddlers (792/1 295, 61.2%) and less in adolescents (115/1 295, 8.8%) than in other regions. Regarding different age groups, poisoning in adolescent happened more in Northeast China (121/457, 26.5%), North China (240/1 034, 23.2%), and Northwest China (245/1 064, 23.0%). The rate of discharge under medical advice, discharge without medical advice, and mortality rate within the 5 years were 77.0% (6 458/8 385), 20.8% (1 743/8 385), 0.5% (40/8 385), respectively. Conclusions: Poisoning is more common in male and toddlers. Poisonous substances show a regional characteristic and vary in different age groups, with drugs and insecticides as the most common substances.

The NADH recycling enzymes TsaC and TsaD regenerate reducing equivalents for Rieske oxygenase chemistry

Many microorganisms use both biological and nonbiological molecules as sources of carbon and energy. This resourcefulness means that some microorganisms have mechanisms to assimilate pollutants found in the environment. One such organism is Comamonas testosteroni, which metabolizes 4-methylbenzenesulfonate and 4-methylbenzoate using the TsaMBCD pathway. TsaM is a Rieske oxygenase, which in concert with the reductase TsaB consumes a molar equivalent of NADH. Following this step, the annotated short-chain dehydrogenase/reductase and aldehyde dehydrogenase enzymes TsaC and TsaD each regenerate a molar equivalent of NADH. This co-occurrence ameliorates the need for stoichiometric addition of reducing equivalents and thus represents an attractive strategy for integration of Rieske oxygenase chemistry into biocatalytic applications. Therefore, in this work, to overcome the lack of information regarding NADH recycling enzymes that function in partnership with Rieske non-heme iron oxygenases (Rieske oxygenases), we solved the X-ray crystal structure of TsaC to a resolution of 2.18 Å. Using this structure, a series of substrate analog and protein variant combination reactions, and differential scanning fluorimetry experiments, we identified active site features involved in binding NAD+ and controlling substrate specificity. Further in vitro enzyme cascade experiments demonstrated the efficient TsaC- and TsaD-mediated regeneration of NADH to support Rieske oxygenase chemistry. Finally, through in-depth bioinformatic analyses, we illustrate the widespread co-occurrence of Rieske oxygenases with TsaC-like enzymes. This work thus demonstrates the utility of these NADH recycling enzymes and identifies a library of short-chain dehydrogenase/reductase enzyme prospects that can be used in Rieske oxygenase pathways for in situ regeneration of NADH.

Custom tuning of Rieske oxygenase reactivity

Rieske oxygenases use a Rieske-type [2Fe-2S] cluster and a mononuclear iron center to initiate a range of chemical transformations. However, few details exist regarding how this catalytic scaffold can be predictively tuned to catalyze divergent reactions. Therefore, in this work, using a combination of structural analyses, as well as substrate and rational protein-based engineering campaigns, we elucidate the architectural trends that govern catalytic outcome in the Rieske monooxygenase TsaM. We identify structural features that permit a substrate to be functionalized by TsaM and pinpoint active-site residues that can be targeted to manipulate reactivity. Exploiting these findings allowed for custom tuning of TsaM reactivity: substrates are identified that support divergent TsaM-catalyzed reactions and variants are created that exclusively catalyze dioxygenation or sequential monooxygenation chemistry. Importantly, we further leverage these trends to tune the reactivity of additional monooxygenase and dioxygenase enzymes, and thereby provide strategies to custom tune Rieske oxygenase reaction outcomes.

Properties of Cosmic-Ray Sulfur and Determination of the Composition of Primary Cosmic-Ray Carbon, Neon, Magnesium, and Sulfur: Ten-Year Results from the Alpha Magnetic Spectrometer

We report the properties of primary cosmic-ray sulfur (S) in the rigidity range 2.15 GV to 3.0 TV based on 0.38×10^{6} sulfur nuclei collected by the Alpha Magnetic Spectrometer experiment (AMS). We observed that above 90 GV the rigidity dependence of the S flux is identical to the rigidity dependence of Ne-Mg-Si fluxes, which is different from the rigidity dependence of the He-C-O-Fe fluxes. We found that, similar to N, Na, and Al cosmic rays, over the entire rigidity range, the traditional primary cosmic rays S, Ne, Mg, and C all have sizeable secondary components, and the S, Ne, and Mg fluxes are well described by the weighted sum of the primary silicon flux and the secondary fluorine flux, and the C flux is well described by the weighted sum of the primary oxygen flux and the secondary boron flux. The primary and secondary contributions of the traditional primary cosmic-ray fluxes of C, Ne, Mg, and S (even Z elements) are distinctly different from the primary and secondary contributions of the N, Na, and Al (odd Z elements) fluxes. The abundance ratio at the source for S/Si is 0.167±0.006, for Ne/Si is 0.833±0.025, for Mg/Si is 0.994±0.029, and for C/O is 0.836±0.025. These values are determined independent of cosmic-ray propagation.

A novel inducible haematopoietic cell-depleting mouse model for chimeric complementation of blood cells

Haematopoietic stem cell transplantation (HSCT) is widely used in regenerative medicine. HSCT can be used not only to treat certain types of blood cancer and immune disorders but also to induce immune tolerance in organ transplantation. However, the inadequacy of HSCs available for transplantation is still a major hurdle for clinical applications. Here, we established a novel inducible haematopoietic cell-depleting mouse model and tested the feasibility of using chimeric complementation to regenerate HSCs and their progeny cells. Large populations of syngeneic and major histocompatibility-mismatched haematopoietic cells were successfully regenerated by this model. The stable allogeneic chimeric mice maintained a substantial population of donor HSCs and Tregs, which indicated that the donor allogeneic HSCs successfully repopulated the recipient blood system, and the regenerated donor Tregs played essential roles in establishing immune tolerance in the allogeneic recipients. In addition, rat blood cells were detected in this model after xenotransplantation of rat whole bone marrow (BM) or Lin^- BM cells. This mouse model holds promise for regenerating xenogeneic blood cells, including human haematopoietic cells.

Leveraging a Structural Blueprint to Rationally Engineer the Rieske Oxygenase TsaM

Rieske nonheme iron oxygenases use two metallocenters, a Rieske-type [2Fe-2S] cluster and a mononuclear iron center, to catalyze oxidation reactions on a broad range of substrates. These enzymes are widely used by microorganisms to degrade environmental pollutants and to build complexity in a myriad of biosynthetic pathways that are industrially interesting. However, despite the value of this chemistry, there is a dearth of understanding regarding the structure-function relationships in this enzyme class, which limits our ability to rationally redesign, optimize, and ultimately exploit the chemistry of these enzymes. Therefore, in this work, by leveraging a combination of available structural information and state-of-the-art protein modeling tools, we show that three "hotspot" regions can be targeted to alter the site selectivity, substrate preference, and substrate scope of the Rieske oxygenase p-toluenesulfonate methyl monooxygenase (TsaM). Through mutation of six to 10 residues distributed between three protein regions, TsaM was engineered to behave as either vanillate monooxygenase (VanA) or dicamba monooxygenase (DdmC). This engineering feat means that TsaM was rationally engineered to catalyze an oxidation reaction at the meta and ortho positions of an aromatic substrate, rather than its favored native para position, and that TsaM was redesigned to perform chemistry on dicamba, a substrate that is not natively accepted by the enzyme. This work thus contributes to unlocking our understanding of structure-function relationships in the Rieske oxygenase enzyme class and expands foundational principles for future engineering of these metalloenzymes.

[Exposure level of neonicotinoid pesticides and their metabolites in pregnant women in the suburb of Shanghai]

In 2021, a total of 151 pregnant women were selected from the suburb of Shanghai. A questionnaire survey was conducted to obtain data about maternal age, gestational week, total annual household income, education level and passive smoking among pregnant women and one spot urine was collected. The concentrations of eight neonicotinoid pesticides and four metabolites in urine were measured by ultra-high performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry. The differences in detection frequencies and concentrations of neonicotinoid pesticides and their metabolites among pregnant women with different characteristics were compared, and the influencing factors of the detection of neonicotinoid pesticides in urine were analyzed. The results showed that at least one neonicotinoid pesticide was detected in 93.4% (141 samples) of urine samples. The detection frequencies of N-desmethyl-acetamiprid, clothianidin, thiamethoxam, and N-desmethyl-clothianidin were high, about 78.1% (118 samples), 75.5% (114 samples), 68.9% (104 samples), and 44.4% (67 samples), respectively. The median concentration of the sum of all neonicotinoid pesticides was 2.66 μg/g. N-desmethyl-acetamiprid had the highest detection concentration with a median concentration of 1.04 μg/g. A lower urinary detection frequency of imidacloprid and its metabolites was seen in pregnant women aged 30-44 years [OR (95%CI): 0.23 (0.07-0.77)]. A higher detection frequency of clothianidin and its metabolites was seen in pregnant women with per capita annual household income≥100, 000 yuan [OR (95%CI): 6.15 (1.56-24.28)]. There was widespread exposure to neonicotinoid pesticides and their metabolites in pregnant women from the suburb of Shanghai, which might pose potential health risks to pregnant women, and maternal age and household income were potential influencing factors of the exposure to neonicotinoid pesticides.

Phenylacetylglutamine as a novel biomarker of type 2 diabetes with distal symmetric polyneuropathy by metabolomics

PURPOSE

Type 2 diabetes mellitus (T2DM) with distal symmetric polyneuropathy (DSPN) is a disease involving the nervous system caused by metabolic disorder, while the metabolic spectrum and key metabolites remain poorly defined.

METHODS

Plasma samples of 30 healthy controls, 30 T2DM patients, and 60 DSPN patients were subjected to nontargeted metabolomics. Potential biomarkers of DSPN were screened based on univariate and multivariate statistical analyses, ROC curve analysis, and logistic regression. Finally, another 22 patients with T2DM who developed DSPN after follow-up were selected for validation of the new biomarker based on target metabolomics.

RESULTS

Compared with the control group and the T2DM group, 6 metabolites showed differences in the DSPN group (P < 0.05; FDR < 0.1; VIP > 1) and a rising step trend was observed. Among them, phenylacetylglutamine (PAG) and sorbitol displayed an excellent discriminatory ability and associated with disease severity. The verification results demonstrated that when T2DM progressed to DSPN, the phenylacetylglutamine content increased significantly (P = 0.004).

CONCLUSION

The discovered and verified endogenous metabolite PAG may be a novel potential biomarker of DSPN and involved in the disease pathogenesis.

Temporal Structures in Electron Spectra and Charge Sign Effects in Galactic Cosmic Rays

We present the precision measurements of 11 years of daily cosmic electron fluxes in the rigidity interval from 1.00 to 41.9 GV based on 2.0×10^{8} electrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The electron fluxes exhibit variations on multiple timescales. Recurrent electron flux variations with periods of 27 days, 13.5 days, and 9 days are observed. We find that the electron fluxes show distinctly different time variations from the proton fluxes. Remarkably, a hysteresis between the electron flux and the proton flux is observed with a significance of greater than 6σ at rigidities below 8.5 GV. Furthermore, significant structures in the electron-proton hysteresis are observed corresponding to sharp structures in both fluxes. This continuous daily electron data provide unique input to the understanding of the charge sign dependence of cosmic rays over an 11-year solar cycle.

Association between sarcopenia and prediabetes among non-elderly US adults

AIM

To explore the specific association between sarcopenia and prediabetes based on large population samples.

METHODS

A total of 16,116 U.S. adults aged 20-59 with dual energy X-ray absorptiometry (DXA) was identified from the National Health and Nutrition Examination Surveys (NHANES). Sarcopenia was defined according to appendicular skeletal muscle mass (ASM) adjusted for body mass index (BMI). Multivariable binary logistic regression models were used to ascertain odds ratios (ORs) for developing prediabetes. Stratified analyses were also performed.

RESULTS

Prevalence of prediabetes was higher in the sarcopenia group (n = 1055) compared with the non-sarcopenia group (n = 15,061) (45.50% vs 28.74%, P < 0.001). Sarcopenia was strongly associated with an increased risk of prediabetes after full adjustment (OR = 1.21, 95CI%: 1.05, 1.39, P = 0.009). In the stratified analysis, this association remained significant independent of obesity, triglycerides, and low-density lipoprotein cholesterol levels. When sarcopenia subjects combined with obesity especially central obesity, the risk of prediabetes was the highest (OR = 2.63, 95CI%: 2.22, 3.11, P < 0.001). Furthermore, a greater proportion of any of impaired glucose tolerance (IGT) individuals was observed in the sarcopenia group compared to the non-sarcopenia group among prediabetes population (41.72% vs 24.06%, P < 0.001).

CONCLUSIONS

Sarcopenia was positively associated with prevalent prediabetes especially IGT in the non-elderly. Moreover, synergistic interactions between the sarcopenia and obesity could greatly increase the risk of prediabetes.

Solvent-Free Synthesis of Magnetic Sewage Sludge-Derived Biochar for Heavy Metal Removal from Wastewater

The commonly used two-step and one-pot synthesis methods for producing biochar require the use of iron salt solutions, resulting in the undesirable consequences of energy consumption for dewatering and potential pollution risks. To address this drawback, a magnetic sewage sludge-derived biochar (MSBC-2) was synthesized by a solvent-free method in this study. The pseudo-second-order kinetic model and Langmuir model provided the best fit to the experimental data, implying a monolayered chemisorption process of Pb2+, Cd2+and Cu2+ onto MSBC-2. As the reaction temperature increased from 25 °C to 45 °C, the maximum adsorption capacities increased from 113.64 mg·g−1 to 151.52 mg·g−1 for Pb2+, from 101.01 mg·g−1 to 109.89 mg·g−1 for Cd2+ and from 57.80 mg·g−1 to 74.07 mg·g−1 for Cu2+, respectively. Thermodynamic parameters (ΔG0 < 0, ΔS0 > 0, ΔH0 > 0) revealed that the adsorption processes of all three metals by MSBC-2 were favourable, spontaneous and endothermic. Surface complexation, cation-π interaction, ion exchange and electrostatic attraction mechanisms were involved in the adsorption of Pb2+, Cd2+ and Cu2+ onto MSBC-2. Overall, this study will provide a new perspective for the synthesis of magnetic biochar and MSBC-2 shows great potential as an adsorbent for heavy metal removal.

[Effect of topical glucocorticoid in treating phimosis on urinary tract infection of vesicoureteral reflux in infants]

Objective: To evaluate the effect of topical glucocorticoid in treating phimosis on urinarytract infection(UTI) of vesicoureteral reflux(VUR) in infants. Methods: Clinical data of infants with UTI diagnosed as primary VUR admitted to our hospital from January 2016 to January 2021 were retrospectively analyzed. The children were divided into three groups:the effective group (topical glucocorticoid was effective in the treatment of phimosis), the ineffective group(topical glucocorticoid was ineffective in the treatment of phimosis), and the untreated group(phimosis was not treated). Age of onset, degree of reflux, side and other indicators were compared to understand the effectiveness of topical glucocorticoid in treating phimosis, and the clinical characteristics of repeated UTI with VUR in treated phimosis and untreated phimosis. Results: A total of 544 children were included. Among them, 59 cases were treated with topical glucocorticoid for phimosis, 48 cases in the effective group, and their age was (12.5±8.4) months;11 cases in the ineffective group,and their age was (11.2±8.9) months. There were 485 cases in the untreated group, and their age was (13.1±9.3) months.The effective rate of topical glucocorticoid in the treatment of phimosis was 81.36%. There were 12 cases(12/48) of recurrent UTI in the effective group and 213 cases (213/485)of recurrent UTI in the untreated group, and the difference between the two groups was statistically significant (P=0.008). Conclusion: Treatment of phimosis with topical glucocorticoid is an effective, easy to perform, and cost-effective method, and can effectively reduce the risk of recurrent UTI in infants with primary VUR.

[A multicenter epidemiological study of acute bacterial meningitis in children]

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.

[Research progress of infrared light promoting wound healing]

At present, current stimulation, ultra-sound, and light therapy have become effective methods to promote wound healing. Among them, infrared light is the most widely used method and is one of the important methods to promote wound healing. The therapeutic effect of infrared light on wounds is related to the effect of photobiomodulation on cells and molecules on the skin surface, but the mechanism by which photobiomodulation of infrared light promotes wound healing has not been fully elucidated. Therefore, it is necessary to study the action characteristics and the mechanism of photo-biomodulation of infrared light in promoting wound healing. This article reviews the effect of different types of infrared light on wound healing and the mechanism of infrared light in promoting wound healing.

Peripheral and intestinal mucosal-associated invariant T cells in premature infants with necrotizing enterocolitis

Background: Necrotizing enterocolitis (NEC) is a potentially fatal inflammatory gastrointestinal disease in preterm infants with unknown pathogenesis. Mucosal-associated invariant T (MAIT) cells primarily accumulate at sites where exposure to microbes is ubiquitous and regulate immunological responses. As the implications of these cells in NEC development in premature infants remain unknown, we investigated the role and characteristics of MAIT cells in NEC pathogenesis.

Methods: The percentage of different MAIT cell subsets in peripheral blood samples of 30 preterm infants with NEC and 22 control subjects was estimated using flow cytometry. The frequency of MAIT cells in the intestinal tissues of five NEC patients and five control subjects was also examined. The level of serum cytokines was estimated using cytometric bead array. Potential associations between the different measurements were analyzed using the Spearman’s correlation test.

Results: Compared with controls, the NEC patients were found to have significantly reduced percentages of circulating CD161⁺ CD3⁺ CD8αα⁺ T cells and CD161⁺ CD3⁺ TCRγδ^-TCRVa7.2⁺ MAIT cells. In the intestinal tissues, the percentage of MAIT cells was significantly higher in samples from the NEC patients than the controls. Furthermore, the percentage of circulating MAIT cells in the peripheral blood samples was inversely correlated with that in the intestinal tissues of the NEC patients. The percentage of CD8αα⁺ MAIT cells was found to be significantly reduced in both peripheral blood and intestinal tissues of NEC patients. Following treatment, the frequency of circulating MAIT cells significantly increased in NEC patients and reached a level similar to that in the control subjects. However, there was no difference in the percentage of circulating CD8αα⁺ MAIT cells before and after treatment in the NEC patients.

Conclusion: Our results suggested that during the development of NEC MAIT cells accumulate in the inflammatory intestinal tissues, while the percentage of CD8aa⁺ MAIT cells is significantly decreased, which may lead to the dysfunction of MAIT cells in gut immunity.

Systematic Identification of Genomic Markers for Guiding Iron Oxide Nanoparticles in Cervical Cancer Based on Translational Bioinformatics

Purpose

Magnetic iron oxide nanoparticle (MNP) drug delivery system is a novel promising therapeutic option for cancer treatment. Material issues such as fabrication and functionalized modification have been investigated; however, pharmacologic mechanisms of bare MNPs inside cancer cells remain obscure. This study aimed to explore a systems pharmacology approach to understand the reaction of the whole cell to MNPs and suggest drug selection in MNP delivery systems to exert synergetic or additive anti-cancer effects.

Methods

HeLa and SiHa cell lines were used to estimate the properties of bare MNPs in cervical cancer through 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) and enzyme activity assays and cellular fluorescence imaging. A systems pharmacology approach was utilized by combining bioinformatics data mining with clinical data analysis and without a predefined hypothesis. Key genes of the MNP onco-pharmacologic mechanism in cervical cancer were identified and further validated through transcriptome analysis with quantitative reverse transcription PCR (qRT-PCR).

Results

Low cytotoxic activity and cell internalization of MNP in HeLa and SiHa cells were observed. Lysosomal function was found to be impaired after MNP treatment. Protein tyrosine kinase 2 beta (PTK2B), liprin-alpha-4 (PPFIA4), mothers against decapentaplegic homolog 7 (SMAD7), and interleukin (IL) 1B were identified as key genes relevant for MNP pharmacology, clinical features, somatic mutation, and immune infiltration. The four key genes also exhibited significant correlations with the lysosome gene set. The qRT-PCR results showed significant alterations in the expression of the four key genes after MNP treatment in HeLa and SiHa cells.

Conclusion

Our research suggests that treatment of bare MNPs in HeLa and SiHa cells induced significant expression changes in PTK2B, PPFIA4, SMAD7, and IL1B, which play crucial roles in cervical cancer development and progression. Interactions of the key genes with specific anti-cancer drugs must be considered in the rational design of MNP drug delivery systems.

Properties of Daily Helium Fluxes

We present the precision measurement of 2824 daily helium fluxes in cosmic rays from May 20, 2011 to October 29, 2019 in the rigidity interval from 1.71 to 100 GV based on 7.6×10^{8} helium nuclei collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The helium flux and the helium to proton flux ratio exhibit variations on multiple timescales. In nearly all the time intervals from 2014 to 2018, we observed recurrent helium flux variations with a period of 27 days. Shorter periods of 9 days and 13.5 days are observed in 2016. The strength of all three periodicities changes with time and rigidity. In the entire time period, we found that below ∼7  GV the helium flux exhibits larger time variations than the proton flux, and above ∼7  GV the helium to proton flux ratio is time independent. Remarkably, below 2.4 GV a hysteresis between the helium to proton flux ratio and the helium flux was observed at greater than the 7σ level. This shows that at low rigidity the modulation of the helium to proton flux ratio is different before and after the solar maximum in 2014.

POS1116 DIETARY INFLAMMATORY INDEX AND KNEE STRUCTURES ON MRI AND PAIN: A PROSPECTIVE COHORT STUDY

Background

While some individual dietary nutrients/components have been shown to be associated with knee osteoarthritis (OA) progression, the associations of the dietary inflammatory index (DII), which reflects the overall inflammatory potential of a diet, with MRI-detected structural changes and pain have not been investigated.

Objectives

This longitudinal study aimed to determine whether DII scores are associated with knee structural changes and pain over a 10.7-year follow-up in community-dwelling older adults.

Methods

This study utilised the data from a prospective population-based cohort study (mean age 63 years, 51% women) in which 1,099, 875, 768 and 563 participants completed assessments at baseline, 2.6, 5.1 and 10.7 years, respectively. T1-weighted or T2-weighted MRI of the right knee was performed to measure cartilage volume (CV) and bone marrow lesions (BMLs) at baseline and 10.7 years. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain questionnaire was used to measure knee pain at all assessments. Baseline energy-adjusted DII (E-DII) scores were calculated using a validated Food Frequency Questionnaire. X-ray was performed to assess radiographic knee osteoarthritis (ROA). Linear, log-binomial regression and linear mixed-effects modelling with adjustments for covariates were used to examine the associations of E-DII with CV loss, BML size increase and knee pain, respectively. Pain trajectories (i.e., ‘Minimal Pain’, ‘Mild Pain’, and ‘Moderate Pain’) were previously identified in this cohort using group-based trajectory modelling [1]. Multi-nominal logistic regression was used to examine the association between E-DII and pain trajectory groups.

Results

The mean E-DII at baseline was -0.48±1.39. In multivariable analyses, E-DII score was not associated with tibial CV loss and BML size increase [CV loss: β=0.03% per annum, 95%CI -0.01–0.06; BML size increase: relative risk (RR)=0.94, 95%CI 0.84–1.05;]. Higher E-DII was associated with greater pain score over 10.7 years (β=0.21, 95%CI 0.004-0.43) and an increased risk of belonging to ‘Moderate pain’ as compared to ‘Minimal Pain’ trajectory group [relative risk ratio (RRR): 1.19, 95%CI 1.02-1.39] after adjustment for age, body mass index, physical activity, education level, employment, emotional problems, comorbidities, and ROA.

Conclusion

Higher DII was associated with greater pain score and higher risk of more severe pain trajectory, but not structural changes, suggesting discordance between effects of diet on structural damage and pain, and that targeting pro-inflammatory diets may be beneficial to reduce pain.

References

[1]Pan F, Tian J, Aitken D, Cicuttini F, Jones G. Predictors of pain severity trajectory in older adults: a 10.7-year follow-up study. Osteoarthritis Cartilage. 2018;26(12):1619-26.

Disclosure of Interests

None declared

AB1474 LIPIDOMIC PROFILING IDENTIFIES SERUM LIPIDS ASSOCIATED WITH PERSISTENT MULTISITE MUSCULOSKELETAL PAIN

Background

Lipid mediators have been suggested to have a role in pain sensitivity and response; however, longitudinal data on lipid metabolites and persistent multisite musculoskeletal pain (MSMP) are lacking.

Objectives

This study was to identify lipid metabolic markers for persistent MSMP.

Methods

Lipidomic profiling of 807 lipid species was performed on serum samples of 536 participants from a cohort study. MSMP was measured by a questionnaire and defined as painful sites ≥4. Persistent MSMP was defined as having MSMP at every visit. Logistic regression was used with adjustment for potential confounders. The Benjamini Hochberg method was used to control for multiple testing.

Results

A total of 530 samples with 807 lipid metabolites passed quality control. Mean age at baseline was 61.54±6.57 years and 50% were females. One hundred and twelve (21%) of the participants had persistent MSMP. Persistent MSMP was significantly associated with lower levels of monohexosylceramide (HexCer)(d18:1/22:0 and d18:1/24:0), acylcarnitine (AC)(26:0) and lysophosphatidylcholine (LPC)(18:1 [sn1], 18:2 [sn1], 18:2 [sn2], and 15-MHDA[sn1] [104_sn1]) after controlling for multiple testing. After adjustment for age, sex, body mass index, diabetes status, and physical activity, HexCer(d18:1/22:0 and d18:1/24:0) and LPC(18:1 [sn1] and 15-MHDA [sn1] [104_sn1]) were significantly associated with persistent MSMP [Odds Ratio (OR) ranging from 0.24 - 0.32]. Two lipid classes -- HexCer and LPC were negatively associated with persistent MSMP after adjustment for covariates (OR=0.19 and 0.21, respectively).

Conclusion

This study identified four novel lipid signatures of persistent MSMP, suggesting that lipid metabolism is involved in the pathogenesis of persistent pain.

Disclosure of Interests

None declared

[Clinical features of children with Cunninghamella spp. infection: a case report and literature review]

We report a case of mucormycosis induced by Cunninghamella spp. infection in a ten-year-old girl with acute lymphoblastic leukemia, who developed fever and respiratory symptoms after chemotherapy and was diagnosed with invasive fungal disease. Peripheral blood DNA sequences were analyzed using metagenomic next-generation sequencing (mNGS), and by comparison with the Pathogens Metagenomics Database (PMDB), we identified Cunninghamella spp. with sequence number 514 as the pathogen. The patient was treated with amphotericin B combined with posaconazole and showed a favorable response. We searched Pubmed, Embase, CNKI, and Wanfang database for reports of cases of Cunninghamella spp. infection in children and retrieved 22 reported cases (including 12 males) with a median age of 13.5 (3-18) years. In these 22 cases, hematological malignancy was the most common underlying condition (19/22), and most of patients experienced an acute onset and rapid progression with respiratory symptoms (14/20) and fever (16/20) as the most common symptoms. CT imaging often showed unilateral lesions with varying imaging findings, including pulmonary nodules or masses, infiltrative changes, and pleural effusion. Definite diagnoses were established in 18 of the cases, and 4 had probable diagnoses; the lungs and skin were the most frequent organs compromised by the infection. A definite diagnosis of Cunninghamella spp. infection still relied on histopathological examination and fungal culture, but the molecular techniques including PCR and mNGS had shown potentials in the diagnosis. Almost all the cases received antifungal treatment after diagnosis (21/22), and 13 patients also underwent surgeries. Death occurred in 9 (42%) of the cases at a median of 19 (4-54) days after onset of the signs or symptoms. The patients receiving antifungal therapy combined with surgery had a high survival rate (9/13, 69%) than those with antifungal therapy alone (3/8, 37%). Invasive fungal disease is a common complication in immunoco-mpromised patients, but Cunninghamella spp. infection is rare and has a high mortality rate. In cases highly suspected of this disease, active diagnosis and early treatment are critical to improve the survival outcomes of the patients.

Low Dose Interleukin-2 Ameliorates Sjögren’s Syndrome in a Murine Model

Sjögren’s syndrome (SS) is a systemic autoimmune disease with no efficient treatment, and it is associated with dysregulated immune cells and impaired interleukin (IL)-2 signaling. IL-2 is critical for the development and maintenance of Treg cells. The use of low dose of IL-2 (LDIL-2) in the treatment of autoimmune diseases is promising, but the efficacy and mechanism in SS therapy are still to be confirmed. This study aims to investigate the therapeutic effect of LDIL-2 on SS in NOD (non-obese diabetic) mice. NOD mice (female, 8 weeks old) were randomly assigned into three groups (n = 8). Low dose of IL-2 (LDIL-2), high dose of IL-2 (HDIL-2), and isometric sterile water (control) were administered subcutaneously daily from week 8 to week 16. LDIL-2 administration significantly recovered the reduction in saliva flow and suppressed lymphocyte inflammation of the submandibular glands (SMGs) when compared with those treated with sterile water as controls (p &lt; 0.05). SS related biomarkers including ANA, Anti-SSA/Ro, and Anti-SSB/La also declined (p &lt; 0.05). In the low dose of IL-2 treated group, the proportion of CD4+CD25+Foxp3+Tregs in both spleen and cervical-lymph-node were higher than control mice (p &lt; 0.05). Furthermore, CD4+Bcl-6+PD-1+CXCR5+Tfh cells, CD4+IFN-γ+Th1 cells, and CD4+IL-17A+Th17 cells were significantly reduced in LDIL-2 group (p &lt; 0.05). Analysis of the SMGs biopsies showed significantly decreased inflammation scores after LDIL-2 administration and an increase of Tregs with immunohistochemical staining. Our findings provide in vivo evidence that LDIL-2 was an effective therapeutic intervention for SS observed in NOD mice and may restore immune balance through the promotion of Treg and suppression of germinal center (GC) B cells and effector T cells.

Structure-Based Strategies for Rieske Oxygenase Catalysis

Rieske Oxygenases are enzymes that showcase the remarkable ability to functionalize an inert C-H bond. These enzymes use a Rieske [2Fe-2S] cluster and a mononuclear iron center to bind and activate molecular oxygen. Using these metallocenters, Rieske Oxygenases have been shown to catalyze a variety of reactions, including one, two, and sequential hydroxylation reactions. This chemistry is important to the biosynthetic pathways of multiple organisms and is thus attractive for industrially building and tailoring natural product scaffolds. Similarly, the chemistry of the Rieske Oxygenases is abundant in degradative pathways and therefore offers compelling strategies for degrading environmental pollutants. However, a traditional lack of structure-function information for this expansive class of enzymes has restricted our ability to capitalize on these important and diverse catalytic strategies. Therefore, our laboratory is working to understand the architectural features of these enzymes that allow them to control and facilitate catalysis. Here, we present our current understanding of how these enzymes selectively catalyze reactions and use structure to guide chemical outcome.

[Application status and prospect of single-cone obturation technique with bioceramic sealers]

Compared with cold lateral condensation and continuous wave of condensation which are classically used in clinical, newly emerging single-cone obturation technique is easy-to-operate as well as time-saving. Especially when combined with bioceramic root canal sealers of improved physicochemical and biological properties, single-cone obturation technique showed satisfactory short-term outcomes in clinical observations. However, difficulties still exist in avoiding the root canal overfilling and in operating the retreatment. Besides, the long-term effects of single-cone obturation with bioceramic sealers still remain unclear. This article makes an overview on the history and development of single-cone obturation ,and provides analysis of its pros and corns. Furthermore, we would also like to summarize its clinical application and look into its future improvements.

Low carbon footprint inhalers in England: a review of dispensing data

Introduction

Due to propellants, metered dose inhalers (pMDIs) have a higher carbon footprint than low carbon footprint inhalers (LCFIs), such as dry powder or soft mist inhalers (1). Consequently, pMDIs contribute 3.5% of the NHS’s CO2 equivalent emissions (2). Local and national guidelines (NICE, British Thoracic Society) have attempted to increase use of LCFIs, but their effects and factors influencing success are unknown.

Aim

To investigate temporal and geographical variation in LCFI dispensing in England over five years.

Methods

Clinical commissioning group (CCG) dispensed items (March 2016-February 2021) were obtained from openprescribing.net for five classes of inhaler where a choice between pMDIs and LCFIs is available: short-acting beta-agonists (SABAs), long-acting beta-agonists (LABAs), inhaled corticosteroids (ICS), ICS plus LABA inhalers (ICS/LABA) and ICS/LABA plus long-acting muscarinic antagonist inhalers (ICS/LABA/LAMA). CCG population age profiles were obtained from the Office for National Statistics. CCG emergency hospital admission and mortality rates were obtained from Public Health England. CCG formularies and guidelines were reviewed to identify where guidance is available to prescribers.

To control for total inhaler dispensing, the key measure used is the %LCFI: the number of LCFI items dispensed relative to the total number of pMDI and LCFI items. Multivariate regression models were used to investigate geographical variation.

Results

The total annual %LCFI increased from 19.5% to 26.3% over the study period. This was driven by the introduction of ICS/LABA/LAMA inhalers in 2018, as %LCFI decreased for SABA, ICS and ICS/LABA inhalers. %LCFI varied between classes. In the final year, it ranged from 6% for both SABA and ICS inhalers, to 41.2% and 43.9% for ICS/LABA and ICS/LABA/LAMA inhalers, respectively. Interestingly, the cost per item for ICS/LABA and ICS/LABA/LAMA inhalers was similar for both pMDIs and LCFIs, but for SABA and ICS inhalers LCFIs were more expensive.

%LCFI in the final year varied between CCGs (10.7% to 30.9%). The North West, and Birmingham and London areas had consistently higher %LCFI for all classes. For SABA and ICS inhalers, both the presence of advice on climate change in CCG guidelines or formularies, and greater CCG asthma prevalence, were significantly associated with higher %LCFI (p&lt;0.05). The proportion of CCG population &lt;15 years had a significant negative association with %LCFI for ICS and ICS/LABA inhalers (p&lt;0.05). There were no clinically significant associations between %LCFI and either emergency hospital admission or mortality rates.

Conclusion

Current initiatives have not been successful in increasing the use of LCFIs, indicating limited implementation of guidelines for unknown reasons. Further action is required to reduce the carbon footprint of inhaler prescribing. Actions to address the financial disincentives to LCFI prescribing, CCG leadership (e.g. guidelines) and the appropriate use of LCFI in young people should be considered. Research into facilitators and barriers to LCFI use would support this. An important limitation is the use of dispensed items data rather than the number of inhalers, although there is no evidence that the number of inhalers per item varies between pMDIs and LCFIs. In addition, the Covid-19 pandemic disrupted prescribing patterns and long-term NHS projects.

References

(1) Wilkinson AJK, Braggins R, Steinbach I, Smith K. Costs of switching to low global warming potential inhalers. An economic and carbon footprint analysis of NHS prescription data in England. BMJ Open. 2019; 9:e028763.

(2) Environmental Audit Committee. UK progress on reducing F-Gas emissions inquiry: Fifth report of session 2017-19. London (UK): House of Commons Environmental Audit Committee; 25 April 2018. Available from https://publications.parliament.uk/pa/cm201719/cmselect/cmenvaud/469/469.pdf: [Accessed 27 September 2021].

Structural and mechanistic basis for redox sensing by the cyanobacterial transcription regulator RexT

Organisms have a myriad of strategies for sensing, responding to, and combating reactive oxygen species, which are unavoidable consequences of aerobic life. In the heterocystous cyanobacterium Nostoc sp. PCC 7120, one such strategy is the use of an ArsR-SmtB transcriptional regulator RexT that senses H₂O₂ and upregulates expression of thioredoxin to maintain cellular redox homeostasis. Different from many other members of the ArsR-SmtB family which bind metal ions, RexT has been proposed to use disulfide bond formation as a trigger to bind and release DNA. Here, we present high-resolution crystal structures of RexT in the reduced and H₂O₂-treated states. These structures reveal that RexT showcases the ArsR-SmtB winged-helix-turn-helix fold and forms a vicinal disulfide bond to orchestrate a response to H₂O₂. The importance of the disulfide-forming Cys residues was corroborated using site-directed mutagenesis, mass spectrometry, and H₂O₂-consumption assays. Furthermore, an entrance channel for H₂O₂ was identified and key residues implicated in H₂O₂ activation were pinpointed. Finally, bioinformatics analysis of the ArsR-SmtB family indicates that the vicinal disulfide “redox switch” is a unique feature of cyanobacteria in the Nostocales order, presenting an interesting case where an ArsR-SmtB protein scaffold has been evolved to showcase peroxidatic activity and facilitate redox-based regulation.

The DNA binding and H₂O₂ sensing mechanisms are revealed for RexT, a transcriptional regulator found in cyanobacteria of the Nostocales order.

Modification of Intestinal Microbiota Dysbiosis by Low-Dose Interleukin-2 in Dermatomyositis: A Post Hoc Analysis From a Clinical Trial Study

The microbiota has been observed altered in autoimmune diseases, including idiopathic inflammatory myopathies (IIMs), and associated with different treatments. Low-dose IL-2 treatment emerges as a new option for active IIMs. This study aims to explore the role of low-dose IL-2 in regulating intestinal dysbiosis involved in the IIMs. In this study, 13 patients with active IIMs were enrolled and received 1 ×10⁶ IU of IL-2 subcutaneously every other day for 12 weeks plus standard care. The clinical response and immune response were assessed. Stool samples were obtained to explore the structural and functional alterations of the fecal microbiota targeting the V3–V4 region of the 16S rRNA gene and analyze their associations with clinical and immunological characteristics. Our study demonstrated that diversity of microbiota decreased remarkably in patients with IIMs, compared to healthy controls. The inflammatory-related bacteria, such as Prevotellaceae increased, while some butyrate-producing bacteria, such as Pseudobutyrivibrio, Lachnospiraceae, Roseburia, and Blautia, decreased significantly. The alteration associated with disease activities in patients with IIMs. After low-dose IL-2 treatment, 92.31% (12/13) of patients achieved IMACS DOI at week 12. Proportion of Treg cells significantly increased at week 12 compared with that in baseline (15.9% [7.73, 19.4%] vs. 9.89% [6.02, 11.8%], P = 0.015). Interestingly, certain butyrate-producing bacteria increase significantly after IL-2 treatment, like Lachnospiraceae, Pseudobutyrivibrio, etc., and are associated with a rise in L-Asparagine and L-Leucine. The effects of low-dose IL-2 on gut microbiota were more apparent in NOD mice. Together, the data presented demonstrated that low-dose IL-2 was effective in active IIMs and highlighted the potential for modifying the intestinal microbiomes of dysbiosis to treat IIMs.

Parental and training coaches' knowledge and attitude towards dental trauma management of children

BACKGROUND

The aim of this study was to evaluate parental and training coaches' knowledge and attitude towards traumatic dental injuries (TDIs) among children.

MATERIAL AND METHODS

A 31-item questionnaire was distributed to the parents and training coaches attending local sporting clubs in Brisbane region, Australia. The questionnaire consisted of five parts (i) demographic and professional information; (ii) TDIs in the primary dentition; (iii) fractures and subluxation of permanent teeth (iv) avulsion of permanent teeth, and (v) information and knowledge related to the management of traumatized teeth. The jamovi (Version 1.6.3) and GraphPad Prism were used for data analysis.

RESULTS

A total of 233 participants were surveyed, 211 parents and 22 coaches. Of all types of injuries, parental knowledge of managing avulsion to permanent teeth was poorest (9.5%), followed by management of injuries of primary teeth (17.5%) and management of fractures or subluxation of permanent teeth (29.4%). Parents in health care occupations had higher satisfaction on self-knowledge in managing TDIs however there was no significant difference in knowledge levels between health care personnel and other professions (P = 0.128). There was a discrepancy between the lack of knowledge and willingness to further self-educate with online platforms being the preferred medium.

CONCLUSION

The study showed a gap in parents' and training coaches' knowledge regarding the management of TDIs among children.

Intestinal butyrate-metabolizing species contribute to autoantibody production and bone erosion in rheumatoid arthritis

The imbalance between pathogenic and beneficial species of the intestinal microbiome and metabolism in rheumatoid arthritis (RA) remains unclarified. Here, using shotgun-based metagenome sequencing for a treatment-naïve patient cohort and a "quasi-paired cohort" method, we observed a deficiency of butyrate-producing species and an overwhelming number of butyrate consumers in RA patients. These outcomes mainly occurred in patients with positive ACPA, with a mean AUC of 0.94. This panel was also validated in established RA with an AUC of 0.986 in those with joint deformity. In addition, we showed that butyrate promoted T_regs, while suppressing T_convs and osteoclasts, due to potentiation of the reduction in HDAC expression and down-regulation of proinflammatory cytokine genes. Dietary butyrate supplementation conferred anti-inflammatory benefits in a mouse model by rebalancing T_FH cells and T_regs, as well as reducing antibody production. These findings reveal the critical role of butyrate-metabolizing species and suggest the potential of butyrate-based therapies for RA patients.

A Cross-Sectional Study of Association between Plasma Selenium Levels and the Prevalence of Osteoarthritis: Data from the Xiangya Osteoarthritis Study

OBJECTIVES

Selenium plays an indispensable role in antioxidant and antiinflammation processes. Oxidative stress and inflammation have been hypothesized to be involved in the pathogenesis of cartilage degeneration. We sought to examine the association between plasma selenium levels and the prevalence of radiographic osteoarthritis (ROA).

DESIGN

A population-based cross-sectional study.

SETTING AND PARTICIPANTS

Individuals aged ≥ 50 years were retrieved from the Xiangya Osteoarthritis (XO) Study, a community-based study conducted among the residents of the rural areas of China.

METHODS

Plasma selenium concentration was measured by inductively coupled plasma-dynamic reaction cell-mass spectrometry. ROA was defined as Kellgren/Lawrence score ≥ 2 in at least one knee, hip or hand joint. The association between plasma selenium levels and ROA was evaluated by applying logistic and spline regression.

RESULTS

A total of 1,032 subjects (women: 52.5%; mean age: 63.1 years; ROA prevalence: 45.4%) were included. Compared with the highest tertile, the odds ratios (ORs) for ROA were 1.24 (95% confidence interval [CI]: 0.91 to 1.68) and 1.77 (95% CI: 1.31 to 2.40) in the middle and lowest tertile of plasma selenium, respectively (P for trend<0.05). The results were not changed materially with adjustment of potential confounders. In addition, subjects who had lower plasma selenium levels exhibited a higher prevalence of ROA in a dose-response relationship manner (P=0.005).

CONCLUSION

This study suggests that subjects with lower levels of plasma selenium exhibited a higher prevalence of ROA in a dose-response relationship manner. However, additional studies are still needed to verify the potential causal relationship.

Periodicities in the Daily Proton Fluxes from 2011 to 2019 Measured by the Alpha Magnetic Spectrometer on the International Space Station from 1 to 100 GV

We present the precision measurement of the daily proton fluxes in cosmic rays from May 20, 2011 to October 29, 2019 (a total of 2824 days or 114 Bartels rotations) in the rigidity interval from 1 to 100 GV based on 5.5×10^{9} protons collected with the Alpha Magnetic Spectrometer aboard the International Space Station. The proton fluxes exhibit variations on multiple timescales. From 2014 to 2018, we observed recurrent flux variations with a period of 27 days. Shorter periods of 9 days and 13.5 days are observed in 2016. The strength of all three periodicities changes with time and rigidity. The rigidity dependence of the 27-day periodicity is different from the rigidity dependences of 9-day and 13.5-day periods. Unexpectedly, the strength of 9-day and 13.5-day periodicities increases with increasing rigidities up to ∼10  GV and ∼20  GV, respectively. Then the strength of the periodicities decreases with increasing rigidity up to 100 GV.

RNA interference in Pardosa pseudoannulata, an important predatory enemy against several insect pests, through ingestion of dsRNA-expressing Escherichia coli

RNA interference is an important technology for gene functional research in many organisms. The pond wolf spider (Pardosa pseudoannulata) is an important natural enemy of rice field pests. To facilitate large-scale gene functional research in this spider species and others, we developed an RNA interference (RNAi) method via ingestion of bacteria expressing dsRNA. The dsRNA targeting a cytochrome P450 monooxygenase (cyp41g2) was expressed in Escherichia coli HT115 (DE3). And then the bacterial suspension was fed to 14-20 days old spiderlings. The mRNA abundance of the target gene was significantly reduced after 3-day's ingestion of bacteria expressing dsRNA, and between day 5 and 7, RNAi efficiency remained stable. Thus, we selected 5 days as the optimum interference time. Furthermore, the bacteria resuspension containing 20 ng/μl dsRNA was selected as the optimum concentration. To evaluate the applicability of this method, three other genes with different tissue expression pattern were also selected as targets. And the mRNA abundance of all the four target genes was significantly reduced with RNAi efficiency between 66.0% and up to 86.9%. The results demonstrated that the oral delivery of bacteria expressing dsRNA would be an effective RNAi method for the gene functional study in P. pseudoannulata.

Erratum: Properties of a New Group of Cosmic Nuclei: Results from the Alpha Magnetic Spectrometer on Sodium, Aluminum, and Nitrogen [Phys. Rev. Lett. 127, 021101 (2021)]

This corrects the article DOI: 10.1103/PhysRevLett.127.021101.