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1.
J Colloid Interface Sci ; 665: 999-1006, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38579390

RESUMO

Piezo-photocatalytic water (deuterium oxide) decomposition is a promising strategy for realizing renewable energy, but the manipulation of the polar center remains a big challenge. This study uses a simple low-temperature hydrothermal process to successfully manufacture ZnmIn2Sm+3 (m = 1-3) (ZnIn2S4, Zn2In2S5 and Zn3In2S6). Incorporating both experimental and theoretical analyses, the structural contraction and local polarization of the Zn-S bond in Zn2In2S5 enhance the piezoelectric response and surface charge accumulation, which facilitate charge transfer and reduce the activation energy of water. Remarkably, Zn2In2S5 exhibits excellent piezoelectric photocatalytic total water splitting performance (H2/O2: 4284.72/1967.00 µmol g-1h-1), which is 1.77 times that of photocatalytic performance. Moreover, a significant enhancement in D2O splitting performance can be obtained for the optimized Zn2In2S5. Our work offers valuable insights into the disclosure of local polarization in catalysts for enhancing piezo-photocatalytic overall water splitting.

2.
RSC Adv ; 14(17): 11771-11774, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38617572

RESUMO

There have been scarce reports about stereoscopic design of N-heteroacenes (NHAs), especially for the electron-deficient π-building blocks. Herein, we report the design and synthesis of a U-shaped bis(pyrene-quinoxaline) (BPQ). Single crystal X-ray diffraction reveals the herringbone stacking pattern and the presence of regular and incompletely closed pores.

3.
World J Gastroenterol ; 30(12): 1714-1726, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38617745

RESUMO

BACKGROUND: Previous studies have reported that low hematocrit levels indicate poor survival in patients with ovarian cancer and cervical cancer, the prognostic value of hematocrit for colorectal cancer (CRC) patients has not been determined. The prognostic value of red blood cell distribution width (RDW) for CRC patients was controversial. AIM: To investigate the impact of RDW and hematocrit on the short-term outcomes and long-term prognosis of CRC patients who underwent radical surgery. METHODS: Patients who were diagnosed with CRC and underwent radical CRC resection between January 2011 and January 2020 at a single clinical center were included. The short-term outcomes, overall survival (OS) and disease-free survival (DFS) were compared among the different groups. Cox analysis was also conducted to identify independent risk factors for OS and DFS. RESULTS: There were 4258 CRC patients who underwent radical surgery included in our study. A total of 1573 patients were in the lower RDW group and 2685 patients were in the higher RDW group. There were 2166 and 2092 patients in the higher hematocrit group and lower hematocrit group, respectively. Patients in the higher RDW group had more intraoperative blood loss (P < 0.01) and more overall complications (P < 0.01) than did those in the lower RDW group. Similarly, patients in the lower hematocrit group had more intraoperative blood loss (P = 0.012), longer hospital stay (P = 0.016) and overall complications (P < 0.01) than did those in the higher hematocrit group. The higher RDW group had a worse OS and DFS than did the lower RDW group for tumor node metastasis (TNM) stage I (OS, P < 0.05; DFS, P = 0.001) and stage II (OS, P = 0.004; DFS, P = 0.01) than the lower RDW group; the lower hematocrit group had worse OS and DFS for TNM stage II (OS, P < 0.05; DFS, P = 0.001) and stage III (OS, P = 0.001; DFS, P = 0.001) than did the higher hematocrit group. Preoperative hematocrit was an independent risk factor for OS [P = 0.017, hazard ratio (HR) = 1.256, 95% confidence interval (CI): 1.041-1.515] and DFS (P = 0.035, HR = 1.194, 95%CI: 1.013-1.408). CONCLUSION: A higher preoperative RDW and lower hematocrit were associated with more postoperative complications. However, only hematocrit was an independent risk factor for OS and DFS in CRC patients who underwent radical surgery, while RDW was not.


Assuntos
Perda Sanguínea Cirúrgica , Neoplasias Colorretais , Humanos , Feminino , Hematócrito , Prognóstico , Neoplasias Colorretais/cirurgia , Eritrócitos
4.
Front Endocrinol (Lausanne) ; 15: 1343977, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628584

RESUMO

Background: This study aimed to characterize the clinical phenotype and genetic variations in patients with Kallmann syndrome (KS). Methods: This study involved the collection and analysis of clinical data from an individual with sporadic KS. Following this, peripheral blood samples were obtained from the patient and his parents. Genomic deoxyribonucleic acid was extracted and subjected to whole-exome sequencing and genomic copy number variation (CNV) detection. Finally, Sanger sequencing was performed to validate the suspected pathogenic variants. Results: Whole-exome sequencing confirmed that the child carried both the IL17RD variant (c.2101G>A, p.Gly701Ser) inherited from the mother and the new CPEB4 variant (c.1414C>T, p.Arg472*). No pathogenic CNVs were identified in CNV testing. Conclusion: Bioinformatics analysis shows that the IL17RD protein undergoing Gly701Ser mutation and is speculated to be phosphorylated and modified, thereby disrupting fibroblast growth factor signaling. This study also suggested that the CPEB4 might play a crucial role in the key signaling process affecting olfactory bulb morphogenesis. Overall, the findings of this study broaden the gene expression profile of KS-related pathogenic genes. This offers a new avenue for exploring the pathogenic mechanism of KS and provides valuable insights for precise clinical diagnosis and treatment strategies for this condition.


Assuntos
Síndrome de Kallmann , Feminino , Criança , Humanos , Síndrome de Kallmann/genética , Variações do Número de Cópias de DNA , Mutação , Fenótipo , Mães , Receptores de Interleucina/genética , Proteínas de Ligação a RNA/genética
5.
Water Res ; 256: 121609, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615601

RESUMO

Lingering inconsistencies in the global methane (CH4) budget and ambiguity in CH4 sources and sinks triggered efforts to identify new CH4 formation pathways in natural ecosystems. Herein, we reported a novel mechanism of light-induced generation of hydroxyl radicals (•OH) that drove the production of CH4 from aquatic dissolved organic matters (DOMs) under ambient conditions. A total of five DOM samples with different origins were applied to examine their potential in photo-methanification production under aerobic conditions, presenting a wide range of CH4 production rates from 3.57 × 10-3 to 5.90 × 10-2 nmol CH4 mg-C-1 h-1. Experiments of •OH generator and scavenger indicated that the contribution of •OH to photo-methanificaiton among different DOM samples reached about 4∼42 %. In addition, Fourier transform infrared spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry showed that the carbohydrate- and lipid-like substances containing nitrogen-bonded methyl groups, methyl ester, acetyl groups, and ketones, were the potential precursors for light-induced CH4 production. Based on the experimental results and simulated calculations, the contribution of photo-methanification of aquatic DOMs to the diffusive CH4 flux across the water-air interface in a typical eutrophic shallow lake (e.g., Lake Chaohu) ranged from 0.1 % to 18.3 %. This study provides a new perspective on the pathways of CH4 formation in aquatic ecosystems and a deeper understanding on the sources and sinks of global CH4.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38629191

RESUMO

Anaprazole, a newly developed oral proton pump inhibitor, was evaluated for safety, tolerability, and pharmacokinetics in healthy Chinese subjects. This study involved administering either anaprazole sodium enteric-coated tablet or placebo, followed by monitoring the incidence and severity of any adverse events (AEs). The pharmacokinetic parameters of anaprazole, its isomer, and main metabolisms were determined. The results showed that both single-dose (2.5-120 mg) and multiple-dose (20 mg once daily, 40 mg once daily, or 20 mg twice daily) oral administration of anaprazole sodium enteric-coated tablet were safe and well tolerated. Following single-dose administration, the median time to reach maximum plasma concentration of anaprazole was between 3.50 and 5.25 hours, with mean elimination half-life of 1.22-3.79 hours. The absorption and elimination of anaprazole in the human body appeared to basically follow linear kinetics. After repeated dosing, steady-state concentrations of anaprazole, its isomer, and primary metabolites were achieved, with a median time to reach maximum plasma concentration of 3-3.75 hours and a mean elimination half-life of 1.61-2.27 hours for anaprazole. There was no significant drug accumulation after multiple-dose oral administration. In conclusion, anaprazole sodium enteric-coated tablets were found to be safe and well tolerated in healthy Chinese individuals. Anaprazole is absorbed and metabolized consistently in the human body without any accumulation.

7.
Foods ; 13(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38611387

RESUMO

Panax notoginseng (P. notoginseng) is a valuable herbal medicine, as well as a dietary food supplement known for its satisfactory clinical efficacy in alleviating blood stasis, reducing swelling, and relieving pain. However, the ability of P. notoginseng to absorb and accumulate cadmium (Cd) poses a significant environmental pollution risk and potential health hazards to humans. In this study, we employed laser-induced breakdown spectroscopy (LIBS) for the rapid detection of Cd. It is important to note that signal uncertainty can impact the quantification performance of LIBS. Hence, we proposed the crater-spectrum feature fusion method, which comprises ablation crater morphology compensation and characteristic peak ratio correction (CPRC), to explore the feasibility of signal uncertainty reduction. The crater morphology compensation method, namely, adding variables using multiple linear regression (MLR) analysis, decreased the root-mean-square error of the prediction set (RMSEP) from 7.0233 µg/g to 5.4043 µg/g. The prediction results were achieved after CPRC pretreatment using the calibration curve model with an RMSEP of 3.4980 µg/g, a limit of detection of 1.92 µg/g, and a limit of quantification of 6.41 µg/g. The crater-spectrum feature fusion method reached the lowest RMSEP of 2.8556 µg/g, based on a least-squares support vector machine (LSSVM) model. The preliminary results suggest the effectiveness of the crater-spectrum feature fusion method for detecting Cd. Furthermore, this method has the potential to be extended to detect other toxic metals in addition to Cd, which significantly contributes to ensuring the quality and safety of agricultural production.

8.
Aesthetic Plast Surg ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578308

RESUMO

BACKGROUND: Levator aponeurectomy is a common operation for mild to moderate blepharoptosis. The accuracy of ptosis correction relied on intraoperative judgement when patients were under local anesthesia. For patients who must receive the operation under general anesthesia, it would be an issue to determine how much length of levator aponeurosis to shorten. To solve this issue, we collected data from patients who underwent the operation under local anesthesia and concluded an algorithm. METHODS: This single-center, prospective bivariate regression study allocated patients of mild to moderate congenital blepharoptosis who received levator aponeurectomy under local anesthesia. Preoperative MRD1 and levator function, intraoperative amount of levator aponeurotic shortening, and postoperative MRD1 were measured. The follow-up period was right after the operation. RESULTS: Twenty-nine patients were included in this trial. Two subjects exited because of not receiving allocated operation and data of the other 27 subjects (including 34 eyelids) were analyzed. A scatter diagram was drawn where x axis referred to levator function and y axis referred to the ratio of the amount of shortening of levator aponeurosis over the height of MRD1 correction. Linear regression showed y = - 0.2717*x + 5.026, R2 = 0.8553. CONCLUSION: A modified algorithm to predict the amount of shortening of levator aponeurosis based on levator function and height of ptosis correction was concluded with better accuracy and clinical feasibility. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

9.
BMC Nephrol ; 25(1): 118, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556867

RESUMO

BACKGROUND: Nonmalignant pleural effusion (NMPE) is common and remains a definite health care problem. Pleural effusion was supposed to be a risk factor for acute kidney injury (AKI). Incidence of AKI in NMPE patients and whether there is correlation between the size of effusions and AKI is unknown. OBJECTIVE: To assess the incidence of AKI in NMPE inpatients and its association with effusion size. STUDY DESIGN AND METHOD: We conducted a retrospective cohort study of inpatients admitted to the Chinese PLA General Hospital with pleural effusion from 2018-2021. All patients with pleural effusions confirmed by chest radiography (CT or X-ray) were included, excluding patients with diagnosis of malignancy, chronic dialysis, end-stage renal disease (ESRD), community-acquired AKI, hospital-acquired AKI before chest radiography, and fewer than two serum creatinine tests during hospitalization. Multivariate logistic regression and LASSO logistic regression models were used to identify risk factors associated with AKI. Subgroup analyses and interaction tests for effusion volume were performed adjusted for the variables selected by LASSO. Causal mediation analysis was used to estimate the mediating effect of heart failure, pneumonia, and eGFR < 60 ml/min/1.73m2 on AKI through effusion volume. RESULTS: NMPE was present in 7.8% of internal medicine inpatients. Of the 3047 patients included, 360 (11.8%) developed AKI during hospitalization. After adjustment by covariates selected by LASSO, moderate and large effusions increased the risk of AKI compared with small effusions (moderate: OR 1.47, 95%CI 1.11-1.94 p = 0.006; large: OR 1.86, 95%CI 1.05-3.20 p = 0.028). No significant modification effect was observed among age, gender, diabetes, bilateral effusions, and eGFR. Volume of effusions mediated 6.8% (p = 0.005), 4.0% (p = 0.046) and 4.6% (p < 0.001) of the effect of heart failure, pneumonia and low eGFR on the development of AKI respectively. CONCLUSION: The incidence of AKI is high among NMPE patients. Moderate and large effusion volume is independently associated with AKI compared to small size. The effusion size acts as a mediator in heart failure, pneumonia, and eGFR.


Assuntos
Injúria Renal Aguda , Insuficiência Cardíaca , Derrame Pleural , Pneumonia , Humanos , Estudos Retrospectivos , Derrame Pleural/diagnóstico por imagem , Derrame Pleural/epidemiologia , Pneumonia/epidemiologia , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/complicações , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/complicações
10.
EMBO J ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605226

RESUMO

Prenatal lethality associated with mouse knockout of Mettl16, a recently identified RNA N6-methyladenosine (m6A) methyltransferase, has hampered characterization of the essential role of METTL16-mediated RNA m6A modification in early embryonic development. Here, using cross-species single-cell RNA sequencing analysis, we found that during early embryonic development, METTL16 is more highly expressed in vertebrate hematopoietic stem and progenitor cells (HSPCs) than other methyltransferases. In Mettl16-deficient zebrafish, proliferation capacity of embryonic HSPCs is compromised due to G1/S cell cycle arrest, an effect whose rescue requires Mettl16 with intact methyltransferase activity. We further identify the cell-cycle transcription factor mybl2b as a directly regulated by Mettl16-mediated m6A modification. Mettl16 deficiency resulted in the destabilization of mybl2b mRNA, likely due to lost binding by the m6A reader Igf2bp1 in vivo. Moreover, we found that the METTL16-m6A-MYBL2-IGF2BP1 axis controlling G1/S progression is conserved in humans. Collectively, our findings elucidate the critical function of METTL16-mediated m6A modification in HSPC cell cycle progression during early embryonic development.

11.
Aesthetic Plast Surg ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598138

RESUMO

BACKGROUND: Periorbital aging is characterized by dermatochalasis, lateral hooding and malformation of multiple eyelid creases. Rejuvenation of periorbital region is of great concern in aging Asians, especially for the females. However, the conventional subbrow blepharoplasty was indicated for mild or moderate skin laxity. For severe laxity, double-eyelid incision is necessarily to be involved. This study aims to improve the severe upper eyelid dermatochalasis through an extended subbrow single-incision approach with desirable outcomes. METHODS: Patients underwent this surgical method from October 2020 to April 2022 were retrospectively reviewed. The redundant skin and orbicularis oculi muscle were excised through a spindle-like subbrow incision delicately designed in the sitting position. Surgical outcomes were evaluated by heights of designed line from the palpebral margin to the pupil center (HPPC), medial cornea (HPMC), and lateral canthus (HPLC) at different follow-ups. The overall satisfaction score of cosmetic outcomes was assessed by an independent surgeon and patients themselves based on the evaluation of: subbrow scar, eyelid symmetry, lateral hooding lifting, visual block improvement and brow shape. RESULTS: A total of 75 cases were reviewed, including 3 men and 72 women. The preoperative HPPC, HPMC, and HPLC were 4.27 ± 0.40, 4.72 ± 0.45 and 3.41 ± 0.35 mm. The values were postoperatively improved to 7.01 ± 0.46, 6.57 ± 0.34 and 5.69 ± 0.26 mm, respectively, presenting significantly different (p < 0.05). The mean surgeon satisfaction scores were 3.6 ± 0.6 (range, 2.0-4.0), and patient satisfaction scores were 3.5 ± 0.6 (range, 2.0-4.0). No hypertrophic scar, sunken upper eyelids or other complications was found. CONCLUSIONS: The modified subbrow blepharoplasty method is an effective and safe alternative for correcting severe upper eyelid skin laxity, which can achieve both good cosmetic outcomes and functional improvement. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

12.
J Robot Surg ; 18(1): 166, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587718

RESUMO

Current meta-analysis was performed to compare robotic hepatectomy (RH) with conventional open hepatectomy (OH) in terms of peri-operative and postoperative outcomes. PubMed, EMBASE, and the Cochrane Library were all searched up for comparative studies between RH and OH. RevMan5.3 software and Stata 13.0 software were used for statistical analysis. Nineteen studies with 1747 patients who received RH and 23,633 patients who received OH were included. Pooled results indicated that patients who received RH were generally younger than those received OH (P < 0.00001). Moreover, RH was associated with longer operative time (P = 0.0002), less intraoperative hemorrhage (P < 0.0001), lower incidence of intraoperative transfusion (P = 0.003), lower incidence of postoperative any morbidity (P < 0.00001), postoperative major morbidity (P = 0.0001), mortalities with 90 days after surgery (P < 0.0001), and shorter length of postoperative hospital stay (P < 0.00001). Comparable total hospital costs were acquired between RH and OH groups (P = 0.46). However, even at the premise of comparable R0 rate (P = 0.86), RH was associated with smaller resected tumor size (P < 0.00001). Major hepatectomy (P = 0.02) and right posterior hepatectomy (P = 0.0003) were less frequently performed in RH group. Finally, we concluded that RH was superior to OH in terms of peri-operative and postoperative outcomes. RH could lead to less intraoperative hemorrhage, less postoperative complications and an enhanced postoperative recovery. However, major hepatectomy and right posterior hepatectomy were still less frequently performed via robotic approach. Future more powerful well-designed studies are required for further exploration.


Assuntos
Hepatectomia , Procedimentos Cirúrgicos Robóticos , Humanos , Hepatectomia/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Perda Sanguínea Cirúrgica , Custos Hospitalares , Tempo de Internação
13.
World J Gastrointest Surg ; 16(3): 807-815, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38577084

RESUMO

BACKGROUND: Ostomy is a common surgery usually performed to protect patients from clinical symptoms caused by distal anastomotic leakage after colorectal cancer (CRC) surgery and perforation or to relieve intestinal obstruction. AIM: To analyze the complications after transverse colostomy closure. METHODS: Patients who underwent transverse colostomy closure from Jan 2015 to Jan 2022 were retrospectively enrolled in a single clinical center. The differences between the complication group and the no complication group were compared. Logistic regression analyses were conducted to find independent factors for overall complications or incision infection. RESULTS: A total of 102 patients who underwent transverse colostomy closure were enrolled in the current study. Seventy (68.6%) patients underwent transverse colostomy because of CRC related causes. Postoperative complications occurred in 30 (29.4%) patients and the most frequent complication occurring after transverse colostomy closure was incision infection (46.7%). The complication group had longer hospital stays (P < 0.01). However, no potential risk factors were identified for overall complications and incision infection. CONCLUSION: The most frequent complication occurring after transverse colostomy closure surgery in our center was incision infection. The operation time, interval from transverse colostomy to reversal, and method of anastomosis might have no impact on the postoperative complications. Surgeons should pay more attention to aseptic techniques.

14.
World J Stem Cells ; 16(3): 287-304, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38577232

RESUMO

BACKGROUND: The self-assembly of solid organs from stem cells has the potential to greatly expand the applicability of regenerative medicine. Stem cells can self-organise into microsized organ units, partially modelling tissue function and regeneration. Dental pulp organoids have been used to recapitulate the processes of tooth development and related diseases. However, the lack of vasculature limits the utility of dental pulp organoids. AIM: To improve survival and aid in recovery after stem cell transplantation, we demonstrated the three-dimensional (3D) self-assembly of adult stem cell-human dental pulp stem cells (hDPSCs) and endothelial cells (ECs) into a novel type of spheroid-shaped dental pulp organoid in vitro under hypoxia and conditioned medium (CM). METHODS: During culture, primary hDPSCs were induced to differentiate into ECs by exposing them to a hypoxic environment and CM. The hypoxic pretreated hDPSCs were then mixed with ECs at specific ratios and conditioned in a 3D environment to produce prevascularized dental pulp organoids. The biological characteristics of the organoids were analysed, and the regulatory pathways associated with angiogenesis were studied. RESULTS: The combination of these two agents resulted in prevascularized human dental pulp organoids (Vorganoids) that more closely resembled dental pulp tissue in terms of morphology and function. Single-cell RNA sequencing of dental pulp tissue and RNA sequencing of Vorganoids were integrated to analyse key regulatory pathways associated with angiogenesis. The biomarkers forkhead box protein O1 and fibroblast growth factor 2 were identified to be involved in the regulation of Vorganoids. CONCLUSION: In this innovative study, we effectively established an in vitro model of Vorganoids and used it to elucidate new mechanisms of angiogenesis during regeneration, facilitating the development of clinical treatment strategies.

15.
Chemosphere ; 357: 142034, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615962

RESUMO

Sulfonamides, quinolones, tetracyclines, and macrolides are the most prevalent classes of antibiotics used in both medical treatment and agriculture. The misuse of antibiotics leads to their extensive dissemination in the environment. These antibiotics can modify the structure and functionality of microbial communities, consequently impacting microbial-mediated nitrogen cycling processes including nitrification, denitrification, and anammox. They can change the relative abundance of nirK/norB contributing to the emission of nitrous oxide, a potent greenhouse gas. This review provides a comprehensive examination of the presence of these four antibiotic classes across different environmental matrices and synthesizes current knowledge of their effects on the nitrogen cycle, including the underlying mechanisms. Such an overview is crucial for understanding the ecological impacts of antibiotics and for guiding future research directions. The presence of antibiotics in the environment varies widely, with significant differences in concentration and type across various settings. We conducted a comprehensive review of over 70 research articles that compare various aspects including processes, antibiotics, concentration ranges, microbial sources, experimental methods, and mechanisms of influence. Antibiotics can either inhibit, have no effect, or even stimulate nitrification, denitrification, and anammox, depending on the experimental conditions. The influence of antibiotics on the nitrogen cycle is characterized by dose-dependent responses, primarily inhibiting nitrification, denitrification, and anammox. This is achieved through alterations in microbial community composition and diversity, carbon source utilization, enzyme activities, electron transfer chain function, and the abundance of specific functional enzymes and antibiotic resistance genes. These alterations can lead to diminished removal of reactive nitrogen and heightened nitrous oxide emissions, potentially exacerbating the greenhouse effect and related environmental issues. Future research should consider diverse reaction mechanisms and expand the scope to investigate the combined effects of multiple antibiotics, as well as their interactions with heavy metals and other chemicals or organisms.

16.
Sci Total Environ ; 928: 172518, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38631637

RESUMO

Microorganisms play important roles in the biogeochemical cycles of lake sediment. However, the integrated metabolic mechanisms governing nitrogen (N) and sulfur (S) cycling in eutrophic lakes remain poorly understood. Here, metagenomic analysis of field and bioreactor enriched sediment samples from a typical eutrophic lake were applied to elucidate the metabolic coupling of N and S cycling. Our results showed significant diverse genes involved in the pathways of dissimilatory sulfur metabolism, denitrification and dissimilatory nitrate reduction to ammonium (DNRA). The N and S associated functional genes and microbial groups generally showed significant correlation with the concentrations of NH4+, NO2- and SO42, while with relatively low effects from other environmental factors. The gene-based co-occurrence network indicated clear cooperative interactions between N and S cycling in the sediment. Additionally, our analysis identified key metabolic processes, including the coupled dissimilatory sulfur oxidation (DSO) and DNRA as well as the association of thiosulfate oxidation complex (SOX systems) with denitrification pathway. However, the enriched N removal microorganisms in the bioreactor ecosystem demonstrated an additional electron donor, incorporating both the SOX systems and DSO processes. Metagenome-assembled genomes-based ecological model indicated that carbohydrate metabolism is the key linking factor for the coupling of N and S cycling. Our findings uncover the coupling mechanisms of microbial N and S metabolism, involving both inorganic and organic respiration pathways in lake sediment. This study will enhance our understanding of coupled biogeochemical cycles in lake ecosystems.

17.
Sci Total Environ ; 928: 172397, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608889

RESUMO

Microplastic biofilms are novel vectors for the transport and spread of pathogenic and drug-resistant bacteria. With the increasing use of bio-based plastics, there is an urgent need to investigate the microbial colonization characteristics of these materials in seawater, particularly in comparison with conventional petroleum-based plastics. Furthermore, the effect of co-occurring contaminants, such as heavy metals, on the formation of microplastic biofilms and bacterial communities remains unclear. In this study, we compared the biofilm bacterial community structure of petroleum-based polyethylene (PE) and bio-based polylactic acid (PLA) in seawater under the influence of zinc ions (Zn2+). Our findings indicate that the biofilm on PLA microplastics in the late stage was impeded by the formation of a mildly acidic microenvironment resulting from the hydrolysis of the ester group on PLA. The PE surface had higher bacterial abundance and diversity, with a more intricate symbiotic pattern. The bacterial structures on the two types of microplastics were different; PE was more conducive to the colonization of anaerobic bacteria, whereas PLA was more favorable for the colonization of aerobic and acid-tolerant species. Furthermore, Zn increased the proportion of the dominant genera that could utilize microplastics as a carbon source, such as Alcanivorax and Nitratireductor. PLA had a greater propensity to harbor and disseminate pathogenic and drug-resistant bacteria, and Zn promoted the enrichment and spread of harmful bacteria such as, Pseudomonas and Clostridioides. Therefore, further research is essential to fully understand the potential environmental effects of bio-based microplastics and the role of heavy metals in the dynamics of bacterial colonization.

18.
Neuroimage ; 292: 120608, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626817

RESUMO

The morphological analysis and volume measurement of the hippocampus are crucial to the study of many brain diseases. Therefore, an accurate hippocampal segmentation method is beneficial for the development of clinical research in brain diseases. U-Net and its variants have become prevalent in hippocampus segmentation of Magnetic Resonance Imaging (MRI) due to their effectiveness, and the architecture based on Transformer has also received some attention. However, some existing methods focus too much on the shape and volume of the hippocampus rather than its spatial information, and the extracted information is independent of each other, ignoring the correlation between local and global features. In addition, many methods cannot be effectively applied to practical medical image segmentation due to many parameters and high computational complexity. To this end, we combined the advantages of CNNs and ViTs (Vision Transformer) and proposed a simple and lightweight model: Light3DHS for the segmentation of the 3D hippocampus. In order to obtain richer local contextual features, the encoder first utilizes a multi-scale convolutional attention module (MCA) to learn the spatial information of the hippocampus. Considering the importance of local features and global semantics for 3D segmentation, we used a lightweight ViT to learn high-level features of scale invariance and further fuse local-to-global representation. To evaluate the effectiveness of encoder feature representation, we designed three decoders of different complexity to generate segmentation maps. Experiments on three common hippocampal datasets demonstrate that the network achieves more accurate hippocampus segmentation with fewer parameters. Light3DHS performs better than other state-of-the-art algorithms.

19.
Neural Netw ; 175: 106311, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38642416

RESUMO

We propose a new score-based model with one-step sampling. Previously, score-based models were burdened with heavy computations due to iterative sampling. For substituting the iterative process, we train a standalone generator to compress all the time steps with the gradient backpropagated from the score network. In order to produce meaningful gradients for the generator, the score network is trained to simultaneously match the real data distribution and mismatch the fake data distribution. This model has the following advantages: (1) For sampling, it generates a fake image with only one step forward. (2) For training, it only needs 10 diffusion steps. (3) Compared with consistency model, it is free of the ill-posed problem caused by consistency loss. On the popular CIFAR-10 dataset, our model outperforms Consistency Model and Denoising Score Matching, which demonstrates the potential of the framework. We further provide more examples on the MINIST and LSUN datasets. The code is available on GitHub.

20.
Bioresour Technol ; : 130674, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642663

RESUMO

Chemical production wastewater contains large amounts of organic solvents (OSs), which pose a significant threat to the environment. In this study, a 10 g·L-1 styrene oxide tolerant strain with broad-spectrum OSs tolerance was obtained via adaptive laboratory evolution. The mechanisms underlying the high OS tolerance of tolerant strain were investigated by integrating physiological, multi-omics, and genetic engineering analyses. Physiological changes are one of the main factors responsible for the high OS tolerance in mutant strains. Moreover, the P-type ATPase GOX_RS04415 and the LysR family transcriptional regulator GOX_RS04700 were also verified as critical genes for styrene oxide tolerance. The tolerance mechanisms of OSs can be used in biocatalytic chassis cell factories to synthesize compounds and degrade environmental pollutants. This study provides new insights into the mechanisms underlying the toxicological response to OS stress and offers potential targets for enhancing the solvent tolerance of G. oxydans.

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