First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9  GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36  GeV/c^{2}, rejecting cross sections above 9.2×10^{-48}  cm at the 90% confidence level.

[Identification and 3D architecture analysis of the LIPC gene mutation in a pedigree with familial hypercholesterolemia-like phenotype]

Objective: To identify and analyze 3D architecture of the mutational sites of susceptible genes in a pedigree with familial hypercholesterolemia-like phenotype (FHLP). Methods: This is a case series study. A pedigree with suspected familial hypercholesterolemia was surveyed. The proband admitted in Beijing Anzhen Hospital in April 2019. Whole-exome sequencing was performed to determine the mutational sites of susceptible genes in the proband. Polymerase chain reaction (PCR) sequencing was used to verify the pathogenic variant on proband's relatives. The structural and functional changes of the proteins were analyzed and predicted by Discovery Studio 4.0 and PyMol 2.0. Results: The patients in the pedigree showed abnormal lipid profiles, especially elevated levels of total cholesterol(TC). The genetic screening detected the c.1330C>T SNP in the exon 8 of lipase C (LIPC) gene, this mutation leads to an amino acid substitution from arginine to cysteine at position 444 (Arg444Cys), in the proband and proband's father and brother. In this family, members with this mutation exhibited elevated TC, whereas lipid profile was normal from the proband's mother without this mutation. This finding indicated that LIPC: c.1330C>T mutation might be the mutational sites of susceptible genes. The analysis showed that Arg444Cys predominantly affected the ligand-binding property of the protein, but had a limited impact on catalytic function. Conclusion: LIPC: c.1330C>T is a new mutational site of susceptible genes in this FHLP pedigree.

[Lipopolysaccharide stimulates macrophages to secrete exosomes containing miR-155-5p to promote activation and migration of hepatic stellate cells]

OBJECTIVE

To observe the effect of exosomes secreted by lipopolysaccharides (LPS)-stimulated macrophages on hepatic stellate cell activation and migration and explore the underlying molecular mechanism.

METHODS

Human monocyte THP-1 cells were induced to differentiate into macrophages using propylene glycol methyl ether acetic acid (PMA, 100 ng/mL, 24 h) followed by stimulation with LPS, and the culture supernatant of macrophages was collected for extraction of the exosomes by ultracentrifugation. The expression of miR-155-5p in the exosomes was detected using qRT-PCR. A Transwell co-culture system was used to observe the effects of the macrophage-derived exosomes on LX2 cell (a hepatic stellate cell line) proliferation, migration, oxidative stress and the expression of fibrosis biomarkers, which were also observed in LX2 cells transfected with miR-155-5p-mimics or miR-155-5p-inhibitors. Western blotting was used to detect the expressions of SOCS1 and its downstream signal pathway proteins.

RESULTS

Treatment with the exosomes from LPS-stimulated macrophages significantly enhanced the proliferation and migration ability of LX2 cells and increased the levels of oxidative stress and expressions of the fibrosis markers such as type Ⅰ collagen (P < 0.05). The expression of miR-155-5p in the exosomes secreted by macrophages was significantly increased after LPS treatment (P < 0.01). LX2 cells overexpressing miR-155-5p also exhibited significantly enhanced proliferation and migration with increased oxidative stress levels and expression of type Ⅰ collagen (P < 0.05), and interference of miR-155-5p expression produced the opposite effects. Western blotting showed that miR-155-5p overexpression obviously inhibited SOCS1 expression and promoted p-Smad2/3, Smad2/3 and RhoA protein expressions in LX2 cells (P < 0.05).

CONCLUSION

LPS stimulation of the macrophages increases miR-155-5p expression in the exosomes to promote activation and migration and increase oxidative stress and collagen production in hepatic stellate cells.

[Clinical analysis of fifteen transplant ureteral stricture cases]

This research aims to explore the clinical characteristics and treatment of transplant ureteral strictures. We retrospectively analyzed the clinical data from fifteen patients diagnosed with transplant ureteral stricture. Of the fifteen patients, five underwent regular ureteral stent or nephrostomy tube exchanges, while ten underwent open surgery. There were no significant differences in basic clinical characteristics between the two groups. The median follow-up time for regular ureteral stent or nephrostomy tube exchanges and open surgery group was 36.8 (11.8-56.0) months and 25.0 (4.5-31.2) months, respectively. Among patients who underwent regular exchanges, one required regular dialysis. Nine patients in the open surgery group had successful removal of the ureteral stent. Our findings suggest that regular ureteral stent or nephrostomy tube exchanges, as well as open surgery, are effective treatment options for transplant ureteral strictures.

Improving the solubility of pseudo-hydrophobic Alzheimer's Disease medicinal chemicals through co-crystal formulation

Natural products are ligands and potential inhibitors of Alzheimer's disease (AD) tau. Dihydromyricetin (DHM) is a CNS active natural product. Despite having signature polyphenolic character, DHM is ostensibly hydrophobic owing to intermolecular hydrogen bonds that shield hydrophilic phenols. Our research shows DHM becomes ionized at near-neutral pH allowing formulation of salts with transformed solubility. The MicroED co-crystal structure with trolamine reveals DHM salts as metastable solids with unlocked hydrogen bonding and a thermodynamic bent to solubilize in water. All salt formulations show better inhibitory activity against AD tau than the non-salt form, with efficacies correlating to enhanced solubilities. These results underscore the role of structural chemistry in guiding selection of solubilizing agents for chemical formulation. We propose DHM salts are appropriate formulations for research as dietary supplements to promote healthy aging by combating protein misfolding. Additionally, DHM is a suitable lead for medicinal chemistry and possible development of CNS pharmaceuticals.

Genome-wide identification and expression analysis of SlRR genes in response to abiotic stress in tomato

The cytokinin two-component signal transduction system (TCS) is involved in many biological processes, including hormone signal transduction and plant growth regulation. Although cytokinin TCS has been well characterized in Arabidopsis thaliana, its role in tomato remains elusive. In this study, we characterized the diversity and function of response regulator (RR) genes, a critical component of TCS, in tomato. In total, we identified 31 RR genes in the tomato genome. These SlRR genes were classified into three subgroups (type-A, type-B and type-C). Various stress-responsive cis-elements were present in the tomato RR gene promoters. Their expression responses under pesticide treatment were evaluated by transcriptome analysis. Their expression under heat, cold, ABA, salinity and NaHCO₃ treatments was further investigated by qRT-PCR and complemented with the available transcription data under these treatments. Specifically, SlRR13 expression was significantly upregulated under salinity, drought, cold and pesticide stress and was downregulated under ABA treatment. SlRR23 expression was induced under salt treatment, while the transcription level of SlRR1 was increased under cold and decreased under salt stress. We also found that GATA transcription factors played a significant role in the regulation of SlRR genes. Based on our results, tomato SlRR genes are involved in responses to abiotic stress in tomato and could be implemented in molecular breeding approaches to increase resistance of tomato to environmental stresses.

Application of B-flow imaging and its enhanced mode in perforator mapping

AIM

To explore the value of B-flow (B-mode blood flow) imaging and its enhanced mode in perforator mapping.

MATERIALS AND METHODS

Before surgery, B-flow imaging, enhanced B-flow imaging, colour Doppler flow imaging (CDFI), and contrast-enhanced ultrasound (CEUS) were used to detect the skin-perforating vessels and small vessels in the fat layer of the donor site. Taking the intra-operative results as the reference standard, the diagnostic consistency and efficiency of the four modes were compared. Statistical analysis was performed using the Friedman M-test, Cochran's Q-test, and the Z-test.

RESULTS

Thirty flaps were excised, with 34 skin-perforating vessels and 25 non-skin-perforating vessels, as confirmed during surgery. In order of the number of skin-perforating vessels detected, the results showed that enhanced B-flow imaging detected more vessels than B-flow imaging and CDFI (all p<0.05), CEUS detected more vessels than B-flow imaging and CDFI (all p<0.05), B-flow imaging detected more vessels than CDFI (p<0.05). All four modes had remarkable and satisfactory diagnostic consistency and effectiveness, but B-flow imaging was the best (sensitivity 100%, specificity 92%, Youden index 0.92). In order of the number of small vessels in the fat layer detected, the results showed that enhanced B-flow imaging detected more vessels than CEUS, B-flow imaging, and CDFI (all p<0.05). CEUS detected more vessels than B-flow imaging and CDFI (all p<0.05).

CONCLUSION

B-flow imaging is an alternative method for perforator mapping. Enhanced B-flow imaging can reveal the microcirculation of flaps.

Association of Dental Caries with Muscle Mass, Muscle Strength, and Sarcopenia: A Community-Based Study

OBJECTIVES

Changes in the oral cavity can reflect other changes throughout the body. This study aimed to investigate the association of dental caries with muscle mass, muscle strength, and sarcopenia, and also to describe the microbial diversity, composition, and community structure of severe dental caries and sarcopenia.

DESIGN

Cross-sectional study based on a Chinese population aged from 50 to 85 years.

SETTING

Communities from Lanxi City, Zhejiang Province, China.

PARTICIPANTS

A total of 1,442 participants aged from 50 to 85 years from a general community (62.8% women; median age 61.0 [interquartile range: 55.0, 68.0]).

MEASUREMENTS

Dental caries was assessed by the decayed, missing, and filled teeth (DMFT) index. Sarcopenia was defined as the presence of both low muscle mass (assessed by dual-energy X-ray absorptiometry scanning) and low muscle strength (assessed by handgrip strength). Multivariate logistic regression models were used to analyze the association of dental caries with muscle mass, muscle strength, and sarcopenia. Fecal samples underwent 16S rRNA profiling to evaluate the diversity and composition of the gut microbiota in patients with severe dental caries and/or sarcopenia.

RESULTS

In the fully adjusted logistic models, dental caries was positively associated with low muscle strength (DMFT ≥ 7: OR, 1.61; 95% CI, 1.25-2.06), and sarcopenia (DMFT ≥ 7: OR, 1.51; 95% CI, 1.01-2.26), but not low muscle mass. Severe dental caries was positively associated with higher alpha-diversity indices (richness, chao1, and ACE, all p < 0.05) and associated with beta-diversity based on Bray-Curtis distance (p = 0.006). The severe dental caries group and the sarcopenia group overlapped with 11 depleted and 13 enriched genera.

CONCLUSION

Dental caries was positively associated with low muscle strength and sarcopenia but not muscle mass, and this association was more pronounced in male individuals. Significant differences were observed in gut microbiota composition both in severe dental caries and sarcopenia, and there was an overlap of the genera features. Future longitudinal studies are needed to clarify causal relationships.

Response of sugar metabolism in the cotyledons and roots of Ricinus communis subjected to salt stress

Ricinus communis is an important oilseed crop worldwide and is also considered one of the best potential plants for salt-affected soil improvement in northeast China. However, little is known about photosynthesis and carbohydrate metabolism in this plant, nor the distribution of carbohydrates in cotyledons and roots under salinity stress. In the present study, seedling growth, gas exchange parameters (P_N , E, g_s and C_i ), carbohydrate (fructose, sucrose, glucose, soluble sugar and starch) metabolism and related enzymes and genes were measured in Ricinus plants. Under salt stress, P_N of cotyledons decreased significantly (P < 0.05), resulting in weak photosynthetic capacity. Furthermore, salt stress increased sucrose and glucose content in cotyledons, but decreased soluble sugar and starch content. However, sucrose increased and starch decreased in roots. This may be correlated with the increasing sugar metabolism under salinity, including notable changes in sugar-related enzyme activities (SPS, SuSy, α-amylase and β-amylase) and gene expression of RcINV, RcSUS, RcAmY, RcBAM and RcGBE1. The results suggest that salinity reduces photosynthesis of cotyledons, alters carbohydrate allocation between cotyledons and roots and also promotes starch utilization in cotyledons and starch biosynthesis in roots, leading to a functional imbalance between cotyledons and roots. Together, these findings provide insights into the crucial role of sugar metabolism in improving salt-tolerance of Ricinus during the early seedling growth stage.

[Efficacy analysis of lidocaine plaster combined with gabapentin in the treatment of herpes zoster neuralgia]

Objective: To evaluate the efficacy and safety of lidocaine plaster combined with gabapentin in the treatment of herpes zoster neuralgia (HZN). Methods: A total of 93 patients diagnosed with HZN from June 4, 2021 to January 5, 2022 in the Department of Pain Clinic of Nanjing Drum Tower Hospital were selected, and their gender was not limited. They were divided into 3 groups by random number table method: group A (n=32) prescribed gabapentin alone, group B (n=30) lidocaine plaster alone, and group C (n=31) lidocaine plaster combined with gabapentin. After excluding patients who did not meet the criteria, there were 28 cases in group A, 28 cases in group B, and 29 cases in group C. The visual analogue scale (VAS), the short-form McGill pain questionnaire (SF-MPQ) score, and drug dosage and adverse reaction in each group at pre-treatment (T0), post-treatment in one week (T1), in two weeks (T2), in four weeks (T4), and in 12 weeks (T12) were recorded and evaluated; Pittsburgh Sleep Quality Index (PSQI) score and Medical Outcomes Study short-form 36 (SF-36) score at T0, T4, and T12 were recorded. Adverse reactions and drug dosage in each group were documented. Repeated measures ANOVA was used to compare the curative effects of the three groups at different time points before and after treatment. Results: The ages of the three groups of patients were (67.8±10.0), (60.9±11.4) and (63.5±12.5) years old respectively (P=0.318), and the proportions of men were 46.4 % (13 cases), 35.7% (10 cases) and 44.8 % (13 cases), respectively (P=0.472). After treatment, the VAS scores and SF-MPQ scores of patients in the three groups were decreased at each time point compared with those before treatment (all P<0.05), the VAS and SF-MPQ scores of patients in group C at T12 time point were 1.2±0.4 and 5.2±2.4 respectively, which were lower than those of patients in groups A and B (both P<0.05). The dosages of gabapentin and lidocaine plaster in group C were lower than those in groups A and B at each time point after treatment (all P<0.05). The PSQI scores of patients in the three groups at T4 and T12 were lower than those before treatment (all P<0.05). The PSQI scores of patients in group C at T4 and T12 were 5.7±1.2 and 4.5±1.2, which were lower than those of patients in groups A and B. (all P<0.05), The SF-36 scores of patients in three groups at T4 and T12 were higher than those before treatment (all P<0.05), and the SF-36 scores of group C at T4 and T12 were 91.7±8.5, 93.1±6.3, which were higher than that of patients in groups A and B (both P<0.05). The incidence of adverse reactions in the three groups were 35.7% (9 cases), 10.7% (3 cases), and 13.8% (4 cases) respectively (P<0.05), the adverse reactions in groups B and C were less than those in group A (P<0.05), and there was no statistical difference between groups B and C (P>0.05). Conclusion: Lidocaine plaster combined with gabapentin has better analgesic effect in the treatment of HZN, with less incidence of adverse reactions, and can reduce the dosage of systemic drugs, improve patients' sleep and quality of life, and thus could provide a safe and effective method for the treatment of HZN.

Hysteresis analysis reveals dissolved carbon concentration - discharge relationships during and between storm events

The dissolved carbon concentration, which is responsible for aquatic ecosystem productivity and water quality, is tightly coupled with hydrological processes. Excess dissolved carbon may exacerbate eutrophication and hypoxia in aquatic ecosystems and lead to deterioration of water quality. Storm events dominate the dynamics of dissolved carbon concentrations, and this nonlinear behavior exhibits significant time scale dependence. Here, we identified inter- and intra-event variability in the dissolved carbon concentration-discharge (C-Q) relationship in an agriculture-intensive catchment. The driving factors of C-Q hysteresis patterns for dissolved inorganic carbon (DIC) and organic carbon (DOC) were quantified by redundancy analysis combined with hierarchical partitioning. At the inter-event scale, DIC exhibited mainly clockwise hysteresis, indicating an exhaustible, proximal source (e.g., groundwater). However, DOC hysteresis was generally counter-clockwise, indicating distal and plentiful sources (e.g., soil water) in the agricultural catchment. Hierarchical partitioning showed that total rainfall, peak discharge and flood intensity explained 28.38% of the total variation in C-Q hysteresis for DIC and 39.87% for DOC at the inter-event scale. At the intra-event scale, time series analysis of dissolved carbon concentration and discharge indicated the interconversion of supply limitation to transport limitation, which depends on the activation of the specific DIC or DOC source zones. These findings provide significant insights into understanding the dynamics of dissolved carbon during storm periods and are important for targeted watershed management practices aimed at reducing carbon loading to surface waters.

Determinants of diarrhoeal infections among users of shared sanitation in informal settlements in Durban, South Africa

Diarrhoeal disease continues to be a major health problem in many parts of the world, especially in developing countries, mainly due to the lack of access to sanitation, water, and hygienic living conditions. Identifying the determinants of diarrhoeal infections continues to be a challenge in developing countries. In this study, we ascertained the factors behind diarrhoea among inhabitants of informal settlements in the city of Durban, South Africa. Prevalence of diarrhoea in the study area varied between 7-year historical clinical records and data collected during the current study (primary data), with the primary data giving the highest monthly prevalence odds ratio (POR) up to 18.1 (±1.6)%. The main factors associated with diarrhoeal infections were open defaecation (POR = 1.8; 95% confidence interval (CI): 0.9-3.12), use of shared sanitation (POR = 1.7; 95%; CI: 1.05-2.26), and exposure to faecal matter around the homes (POR = 1.69; 95% CI: 1.25-3.10). Several other factors were also determined to be associated with diarrhoeal infections, such as hygiene practices in the communities, the non-treatment of water before use, and the presence of solid waste and faecal materials around the households. This study shows that diarrhoeal disease infections in informal settlements could be multifactorial; therefore, a multifactorial approach is needed to reduce these infections. These could include improving education on hygiene practices within the home setting as well as in public places, such as the community ablution blocks.