Identification of metabolic components of carotid plaque in high-risk patients utilizing liquid chromatography-tandem mass spectrometry.

OBJECTIVE: Carotid atherosclerosis is a chronic progressive vascular disease that can be complicated by stroke in severe cases. Prompt diagnosis and treatment of high-risk patients are quite difficult due to the lack of reliable clinical biomarkers. This study aimed to explore potential plaque metabolic markers of stroke-prone risk and relevant targets for pharmacological intervention. METHOD: Carotid intima and plaque sample tissues were obtained from 20 patients with cerebrovascular symptoms of carotid origin. An untargeted metabolomics approach based on liquid chromatography-tandem mass spectrometry was utilized to characterize the metabolic profiles of the tissues. Multivariate and univariate analysis tools were used. RESULTS: A total of 154 metabolites were significantly altered in carotid plaque when compared with thickened intima. Of these, 62 metabolites were upregulated, whereas 92 metabolites were downregulated. Support vector machines identified the 15 most important metabolites, such as N-(cyclopropylmethyl)-N'-phenylurea, 9(S)-HOTrE, ACar 12:2, quinoxaline-2,3-dithiol, and l-thyroxine, as biomarkers for high-risk plaques. Metabolic pathway analysis showed that abnormal purine and nucleotide metabolism, amino acid metabolism, glutathione metabolism, and vitamin metabolism may contribute to the occurrence and progression of carotid atherosclerotic plaque. CONCLUSIONS: Our study identifies the biomarkers and related metabolic mechanisms of carotid plaque, which is stroke-prone, and provides insights and ideas for the precise prevention and targeted intervention of the disease.

Moderate alternate wetting and drying irrigation enhances drought-resistance abilities by improving structural mesophyll conductance of water-saving and drought-resistant rice under severe drought.

Water-saving and drought-resistant rice (WDR) coupled with alternate wetting and drying irrigation (AWDI) possesses a high photosynthetic potential due to higher mesophyll conductance (gm) under drought conditions. However, the physiological and structural contributions to the gm of leaves and their mechanisms in WDR under AWDI are still unclear. In this study, WDR (Hanyou 73) and drought-sensitive rice (Huiliangyou 898) were selected as materials. Three irrigation patterns were established from transplanting to the heading stage, including conventional flooding irrigation (W1), moderate AWDI (W2), and severe AWDI (W3). A severe drought with a soil water potential of -50 kPa was applied for a week at the heading stage across all treatments and cultivars. The results revealed that severe drought reduced gas exchange parameters and gm but enhanced antioxidant enzyme activities and malondialdehyde content in the three treatments and both cultivars. The maximal photosynthetic rate (Amax) of HY73 in the W2 treatment was greater than that in the other combinations of cultivars and irrigation patterns. The contribution of leaf structure (54%) to gm (gm-S, structural gm) was higher than that of leaf physiology (46%) to gm (gm-P, physiological gm) in the W2 treatment of Hanyou 73. Additionally, gm-S was significantly and linearly positively correlated with gm under severe drought. Moreover, both the initial and apparent quantum efficiencies were significantly and positively with gm in rice plants (p < 0.05). These results suggest that the improvements in photosynthesis and yield in the WDR combined with moderate AWDI can mainly be attributed to the enhancement of gm-S under severe drought conditions. Quantum efficiency may be a potential factor in regulating photosynthesis by cooperating with the gm of rice plants under severe drought conditions.

Washed microbiota transplantation improves symptoms and intestinal barrier function in patients with functional bowel disorders: a propensity-score matching analysis.

BACKGROUND: Alterations in the intestinal microbiota may play a role in the pathogenesis of functional bowel disorders (FBDs). Probiotics are widely used to improve intestinal dysbacteriosis in FBDs. In the context of FBDs, washed microbiota transplantation (WMT) appear to be a promising therapeutic option. We aimed to compare probiotics with WMT by using a propensity-score matching analysis (PSMA). METHODS: We conducted a retrospective investigation of 103 patients with FBDs, including irritable bowel syndrome (IBS), functional constipation (FC), functional diarrhea (FDr), functional abdominal bloating (FAB). Patients were divided into the WMT group or probiotics group (taking probiotics capsules). Data on the following parameters were matched for PSMA: age; sex; disease course; body mass index; anxiety; insomnia; tobacco smoking; alcohol consumption; and levels of D-lactate, diamine oxidase, and lipopolysaccharide. Intestinal barrier function (IBF) and symptoms were evaluated both before and after treatment initiation. Prognostic factors were assessed by Cox proportional hazards regression analysis. RESULTS: PSMA identified in 34 matched pairs (11 IBS, 12 FC, 7 FDr, and 4 FAB in the probiotics group and 14 IBS, 13 FC, 5 FDr, and 2 FAB in the WMT group. Improvement of FBD symptoms was greater with WMT than probiotics (P = 0.002). The WMT group had significantly fewer patients with intestinal barrier damage than the probiotics group (38.2% vs. 67.6%, P = 0.041). This improvement of FBD with WMT was further reflected as a reduction in D-lactate levels (P = 0.031). Increased D-lactate levels which were identified as a prognostic factor for FBDs (HR = 0.248, 95%CI 0.093-0.666, P = 0.006) in multivariate Cox regression analysis. CONCLUSION: WMT could improve symptoms and IBF in patients with FBDs. Increased D-lactate levels in patients with FBDs may predict a favorable response to WMT treatment.

Mxene-bpV plays a neuroprotective role in cerebral ischemia-reperfusion injury by activating the Akt and promoting the M2 microglial polarization signaling pathways.

Studies have shown that the inhibition of phosphatase and tensin homolog deleted on chromosome 10 (PTEN)was neuroprotective against ischemia/reperfusion(I/R) injury. Bisperoxovanadium (bpV), a derivative of vanadate, is a well-established inhibitor of PTEN. However, its function islimited due to its general inadequacy in penetrating cell membranes. Mxene(Ti3C2Tx) is a novel two-dimensional lamellar nanomaterial with an excellent ability to penetrate the cell membrane. Yet, the effects of this nanomaterial on nervous system diseases have yet to be scrutinized. Here, Mxene(Ti3C2Tx) was used for the first time to carry bpV(HOpic), creating a new nanocomposite Mxene-bpV that was probed in a cerebral I/R injury model. The findings showed that this synthetic Mxene-bpV was adequately stable and can cross the cell membraneeasily. We observed that Mxene-bpV treatment significantly increased the survival rate of oxygen glucose deprivation/reperfusion(OGD/R)--insulted neurons, reduced infarct sizes and promoted the recovery of brain function after mice cerebral I/R injury. Crucially, Mxene-bpV treatment was more therapeutically efficient than bpV(HOpic) treatment alone over the same period. Mechanistically, Mxene-bpV inhibited the enzyme activity of PTEN in vitro and in vivo. It also promoted the expression of phospho-Akt (Ser473) by repressing PTEN and then activated the Akt pathway to boost cell survival. Additionally, in PTEN transgenic mice, Mxene-bpV suppressed I/R-induced inflammatory response by promoting M2 microglial polarization through PTEN inhibition. Collectively, the nanosynthetic Mxene-bpV inhibited PTEN' enzymatic activity by activating Akt pathway and promoting M2 microglial polarization, and finally exerted neuroprotection against cerebral I/R injury.

OsNAC5 orchestrates OsABI5 to fine-tune cold tolerance in rice.

Due to its tropical origins, rice (Oryza sativa) is susceptible to cold stress, which poses severe threats to production. OsNAC5, a NAC-type transcription factor, participates in the cold stress response of rice, but the detailed mechanisms remain poorly understood. Here, we demonstrate that OsNAC5 positively regulates cold tolerance at germination and in seedlings by directly activating the expression of ABSCISIC ACID INSENSITIVE 5 (OsABI5). Haplotype analysis indicated that single nucleotide polymorphisms in a NAC-binding site in the OsABI5 promoter are strongly associated with cold tolerance. OsNAC5 also enhanced OsABI5 stability, thus regulating the expression of cold-responsive (COR) genes, enabling fine-tuned control of OsABI5 action for rapid, precise plant responses to cold stress. DNA affinity purification sequencing coupled with transcriptome deep sequencing identified several OsABI5 target genes involved in COR expression, including DEHYDRATION-RESPONSIVE ELEMENT BINDING FACTOR 1A (OsDREB1A), OsMYB20, and PEROXIDASE 70 (OsPRX70). In vivo and in vitro analyses suggested that OsABI5 positively regulates COR gene transcription, with marked COR upregulation in OsNAC5-overexpressing lines and downregulation in osnac5 and/or osabi5 knockout mutants. This study extends our understanding of cold tolerance regulation via OsNAC5 through the OsABI5-CORs transcription module, which may be used to ameliorate cold tolerance in rice via advanced breeding.

Construction of a point-of-care electrochemical biosensor for Escherichia coli 16S rRNA analysis based on MoS2 nanoprobes.

Foodborne pathogens are harmful to human health because they can contaminate food and induce diseases. To efficiently distinguish and determine foodborne bacteria, an ultrasensitive point-of-care electrochemical biosensor was designed for 16S rRNA detection by coupling a signal amplification strategy with MoS2-based nanoprobes. Gold nanoparticles and thionine co-functionalized molybdenum disulfide (MoS2) nanocomposites (MoS2-Thi-AuNPs) were used to construct nanoprobes, which can efficiently monitor the detection process and amplify the detection signal. In the presence of Escherichia coli (E. coli) 16S rRNA, a classical sandwiched DNA structure was formed on the surface of a hierarchical flower-like gold nanostructure-decorated screen-printed carbon electrode (HFGN-SPCE), generating an obvious electrochemical signal from Thi. Under optimal conditions, this designed electrochemical biosensor showed a wide dynamic range (0-1.0 × 106 fM), low detection limit (2.8 fM), high selectivity and accepted stability for E. coli 16S rRNA detection in ideal buffers. Moreover, this biosensor can efficiently determine 16S rRNA in milk samples and 10 CFU mL-1 bacterial lysate. All experimental results suggested that this biosensor has a promising application in the detection of foodborne pathogens.

Efficacy of washed microbiota transplantation for therapeutic targets of refractory functional constipation and the influencing factors: a single-center, retrospective, 24-week follow-up study.

BACKGROUND: The efficacy of washed microbiota transplantation (WMT) in terms of refractory functional constipation (FC)-related therapeutic targets and influencing factors have not been elucidated. This study aimed to assess the efficacy and influencing factors of WMT in treating refractory FC-related therapeutic targets. METHODS: The clinical data of patients diagnosed with refractory FC and received with WMT were retrospectively collected. The therapeutic targets included straining, hard stools, incomplete evacuation, a sense of anorectal obstruction, manual maneuvers, and decreased stool frequency. Each target was recorded as 1 (yes) or 0 (no). All patients were followed up for approximately 24 weeks from the end of the first course of WMT. The primary outcomes were the improvement rates for the individual therapeutic targets and the overall response in respect of the therapeutic targets decreased by 2 at weeks 4, 8, and 24. The secondary outcomes were the clinical remission rate (i.e., the proportion of patients with an average of 3 or more spontaneous complete bowel movements per week), clinical improvement rate (i.e., the proportion of patients with an average increase of 1 or more SCBMs/week or patients with remission), stool frequency, Wexner constipation score, Bristol Stool Form Scale (BSFS) score, and adverse events. The factors influencing the efficacy were also analyzed. RESULTS: Overall, 63 patients with 112 WMT courses were enrolled. The improvement rates at weeks 8 and 24 were 45.6% and 35.0%, 42.9% and 38.6%, 45.0% and 35.7%, 55.6% and 44.4%, and 60.9% and 50.0%, respectively, for straining, hard stools, incomplete evacuation, a sense of anorectal obstruction, and decreased stool frequency. The overall response rates were 49.2%, 50.8%, and 42.9%, respectively, at weeks 4, 8, and 24. The rates of clinical remission and clinical improvement were 54.0% and 68.3%, respectively, at weeks 4. The stool frequency, BSFS score, and Wexner constipation score tended to improve post-WMT. Only 22 mild adverse events were observed during the 112 WMT courses and the follow-up. The number of WMT courses was identified to be the independent factor influencing the efficacy. CONCLUSIONS: WMT is efficacious in improving refractory FC-related therapeutic targets. The effectiveness of WMT in the management of FC is enhanced with the administration of multiple courses.

Melatonin Promotes SGT1-Involved Signals to Ameliorate Drought Stress Adaption in Rice.

Drought has become one of the environmental threats to agriculture and food security. Applications of melatonin (MT) serve as an effective way to alleviate drought stress, but the underlying mechanism remains poorly understood. Here, we found that foliar spray of 100-µM MT greatly mitigated the severe drought stress-induced damages in rice seedlings, including improved survival rates, enhanced antioxidant system, and adjusted osmotic balance. However, mutation of the suppressor of the G2 allele of skp1 (OsSGT1) and ABSCISIC ACID INSENSITIVE 5 (OsABI5) abolished the effects of MT. Furthermore, the upregulated expression of OsABI5 was detected in wild type (WT) under drought stress, irrespective of MT treatment, whereas OsABI5 was significantly downregulated in sgt1 and sgt1abi5 mutants. In contrast, no change of the OsSGT1 expression level was detected in abi5. Moreover, mutation of OsSGT1 and OsABI5 significantly suppressed the expression of genes associated with the antioxidant system. These results suggested that the functions of OsSGT1 in the MT-mediated alleviation of drought stress were associated with the ABI5-mediated signals. Collectively, we demonstrated that OsSGT1 was involved in the drought response of rice and that melatonin promoted SGT1-involved signals to ameliorate drought stress adaption.

Physiological Adaptation Mechanisms to Drought and Rewatering in Water-Saving and Drought-Resistant Rice.

Water-saving and drought-resistant rice (WDR) has high a yield potential in drought. However, the photosynthetic adaptation mechanisms of WDR to drought and rehydration have yet to be conclusively determined. Hanyou 73 (HY73, WDR) and Huanghuazhan (HHZ, drought-sensitive cultivar) rice cultivars were subjected to drought stress and rewatering when the soil water potential was −180 KPa in the booting stage. The leaf physiological characteristics were dynamically determined at 0 KPa, −30 KPa, −70 KPa, −180 KPa, the first, the fifth, and the tenth day after rewatering. It was found that the maximum net photosynthetic rate (Amax) and light saturation point were decreased under drought conditions in both cultivars. The change in dark respiration rate (Rd) in HY73 was not significant, but was markedly different in HHZ. After rewatering, the photosynthetic parameters of HY73 completely returned to the initial state, while the indices in HHZ did not recover. The antioxidant enzyme activities and osmoregulatory substance levels increased with worsening drought conditions and decreased with rewatering duration. HY73 had higher peroxidase (POD) activity as well as proline levels, and lower catalase (CAT) activity, ascorbate peroxidase (APX) activity, malondialdehyde (MDA) level, and soluble protein (SP) content during all of the assessment periods compared with HHZ. In addition, Amax was markedly negatively correlated with superoxide dismutase (SOD), POD, CAT, and SP in HY73 (p < 0.001), while in HHZ, it was negatively correlated with SOD, CAT, APX, MDA, Pro, and SP, and positively correlated with Rd (p < 0.001). These results suggest that WDR has a more simplified adaptation mechanism to protect photosynthetic apparatus from damage in drought and rehydration compared with drought-sensitive cultivars. The high POD activity and great SP content would be considered as important physiological bases to maintain high photosynthetic production potential in WDR.

Photosynthetic physiological response of water-saving and drought-resistant rice to severe drought under wetting-drying alternation irrigation.

Water-saving and drought-resistant rice (WDR) is widely grown in central China in recent years. However, studies have not explored the interaction effect of WDR and irrigation regimes on drought-resistance capacities under severe drought at sensitive growth periods. A pot experiment was conducted using a WDR cultivar Hanyou73 (HY73) and traditional high-yielding and drought-sensitive cultivar Huiliangyou 898 (HLY898). Three irrigation regimes, including flooding irrigation (W1), mild wetting-drying alternation irrigation (W2), and severe wetting-drying alternation irrigation (W3), were applied before heading. At heading, severe drought with -50 KPa soil water potential was established for all treatments and cultivars. The findings showed that cultivar HY73 under W2 treatment had the highest yield, 1000-grain yield, filled grain, relative water content, and photosynthesis potential compared with the other combinations. The higher net photosynthetic rate (Pn ) was attributed to larger mesophyll conductance (gm ) in drought for cultivar HY73 under W2 treatment compared with that for cultivar HLY898 and the other water treatments. Enhanced photo-respiration rate may be an important photoprotection mechanism for achieving high Pn for cultivar HY73 coupled with W2 treatment than for other combinations in drought. The relative expression level of OsPIP1;1 gene was significantly down-regulated during drought in all cultivars and water regimes. But OsPIP1;2, OsPIP2;3, OsTIP2;2, and OsTIP3;1 genes were upregulated to alleviate the significant decrease in gs and gm under drought. These results suggest that WDR and mild wetting-drying alternation irrigation (W2) have significant interaction effects in improving photosynthetic production potential by maintaining higher gm under severe drought.