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1.
J Med Chem ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013072

RESUMO

Multitarget strategies are essential in addressing complex diseases, yet developing multitarget-directed ligands (MTDLs) is particularly challenging when aiming to engage multiple therapeutic targets across different tissues. Here, we present a molecular transformer strategy, enhancing traditional MTDLs. By utilizing esterase-driven hydrolysis, this approach mimics the adaptive nature of transformers for enabling molecules to modify their pharmacological effects in response to the biological milieu. By virtual screening and biological evaluation, we identified KGP-25, a novel compound initially targeting the voltage-gated sodium channel 1.8 (Nav1.8) in the peripheral nervous system (PNS) for analgesia, and later the γ-aminobutyric acid subtype A receptor (GABAA) in the central nervous system (CNS) for general anesthesia. Our findings confirm KGP-25's dual efficacy in cellular and animal models, effectively reducing opioid-related side effects. This study validates the molecular transformer approach in drug design and highlights its potential to overcome the limitations of conventional MTDLs, paving new avenues in innovative therapeutic strategies.

2.
J Am Chem Soc ; 146(28): 18879-18885, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38968417

RESUMO

Chiral secondary alkyl amines with a vicinal quaternary stereocenter are undoubtedly important and ubiquitous subunits in natural products and pharmaceuticals. However, their asymmetric synthesis remains a formidable challenge. Herein, we merge the ring-opening 1,2-metallate shift with iridium-catalyzed enantioselective C(sp3)-H borylation of aziridines to deliver these frameworks with high enantioselectivities. We also demonstrated the synthetic application by downstream transformations, including the total synthesis of two Amaryllidaceae alkaloids, (-)-crinane and (+)-mesmebrane.

3.
Bioorg Chem ; 150: 107551, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38971094

RESUMO

Cancer is the most severe health problem facing most people today. Photodynamic therapy (PDT) for tumors has attracted attention because of its non-invasive nature, negligible adverse reactions, and high spatiotemporal selectivity. Developing biocompatible photosensitizers that can target, guide, and efficiently kill cancer cells is desirable in PDT. Here, two amphiphilic organic compounds, PS-I and PSS-II, were synthesized based on the D-π-A structure with a positive charge. The two AIEgens exhibited near-infrared emission, large Stokes shift, high 1O2 and O2-∙ generation efficiency, good biocompatibility, and photostability. They were co-incubated with cancer cells and eventually accumulated to lysosomes by cell imaging experiments. In vitro and in vivo experiments demonstrated that PS-I and PSS-II could effectively kill cancer cells and sufficiently inhibit tumor growth under light irradiation. PS-I had a higher fluorescence quantum yield in the aggregated state, which made it better for bio-imaging in imaging-guided photodynamic therapy. In contrast, PSS-II with a longer conjugated structure had more ROS generation to kill tumor cells under illumination, and the tumor growth inhibition of mice reached 71.95% during the treatment. No observable injury or undesirable outcomes were detected in the vital organs of the mice within the treatment group, suggesting that PSS-II/PS-I had a promising future in efficient imaging-guided PDT for cancer.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39003214

RESUMO

It is urgently necessary to clarify the effect of extraction of impacted mandibular third molar (IMTM) on the periodontal tissue of adjacent second molars (ASMs). In this study, the ASM periodontal condition and pathogenic microbes were assessed before IMTM extraction and at 1, 4, 8 and 12 weeks postoperatively. Based on the inclusion and exclusion criteria, our study revealed that IMTM extractions adversely affected distal - periodontal probing depth (dPPD), attachment loss (dAL), plaque index (dPLI) and bleeding on probing (dBOP) within 8 weeks, but these indices gradually normalize after 12 weeks. The subgingival pathogens near the ASMs distal surface, Porphyromonas and Pseudomonas, were significantly increased postoperatively. Moreover, relevance of ASMs clinical indices and subgingival microbes after IMTM extractions was found. In contrast to the situation in chronic periodontitis, the effects of IMTM extraction on dPPD, dAL, dPLI and dBOP of ASMs were mainly correlated with Pseudomonas. Additionally, while the IMTM extractions have adverse distal periodontal indices of ASMs within 8 weeks and increase subgingival pathogens, the modified triangular flap (MTF) had fewer distal periodontal indices and less Pseudomonas. Compared to the traditional envelope flap and triangular flap, the MTF benefits the periodontal health, which could be considered as the priority option for IMTM extractions.

5.
Exp Ther Med ; 28(2): 326, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38979023

RESUMO

Hyperlipidemia is a strong risk factor for numerous diseases. Resveratrol (Res) is a non-flavonoid polyphenol organic compound with multiple biological functions. However, the specific molecular mechanism and its role in hepatic lipid metabolism remain unclear. Therefore, the aim of the present study was to elucidate the mechanism underlying how Res improves hepatic lipid metabolism by decreasing microRNA-33 (miR-33) levels. First, blood miR-33 expression in participants with hyperlipidemia was detected by reverse transcription-quantitative PCR, and the results revealed significant upregulation of miR-33 expression in hyperlipidemia. Additionally, after transfection of HepG2 cells with miR-33 mimics or inhibitor, western blot analysis indicated downregulation and upregulation, respectively, of the mRNA and protein expression levels of sirtuin 6 (SIRT6). Luciferase reporter analysis provided further evidence for binding of miR-33 with the SIRT6 3'-untranslated region. Furthermore, the levels of peroxisome proliferator-activated receptor-γ (PPARγ), PPARγ-coactivator 1α and carnitine palmitoyl transferase 1 were increased, while the concentration levels of acetyl-CoA carboxylase, fatty acid synthase and sterol regulatory element-binding protein 1 were decreased when SIRT6 was overexpressed. Notably, Res improved the basic metabolic parameters of mice fed a high-fat diet by regulating the miR-33/SIRT6 signaling pathway. Thus, it was demonstrated that the dysregulation of miR-33 could lead to lipid metabolism disorders, while Res improved lipid metabolism by regulating the expression of miR-33 and its target gene, SIRT6. Thus, Res can be used to prevent or treat hyperlipidemia and associated diseases clinically by suppressing hepatic fatty acid synthesis and increasing fatty acid ß-oxidation.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39001732

RESUMO

BACKGROUND: The association of coronary computed tomography angiography (CTA) and left ventricular (LV) myocardium measurements with cancer therapy-related cardiac dysfunction (CTRCD) is limited. OBJECTIVES: In this study, the authors sought to evaluate the changes in coronary arteries and LV myocardium in patients with left breast cancer (BC) receiving anthracycline with or without radiotherapy, with the use of coronary CTA. METHODS: Participants with left BC receiving anthracycline with or without radiotherapy were prospectively included. All participants underwent coronary CTA before and after treatment, including nonenhanced calcium-scoring scan, computed tomography angiography, and dual-energy late enhancement scan. Computed tomographic fractional flow reserve (CT-FFR), pericoronary adipose tissue (PCAT) CT attenuation, and LV segments' extracellular volume (ECV) before and after treatment were compared. Logistic regression analysis was used to assess the association between baseline coronary CTA parameters and CTRCD. RESULTS: Eighty participants receiving anthracycline and 59 participants receiving anthracycline with radiotherapy were included. CT-FFR decreased and PCAT CT attenuation and LV global and segments' ECV increased after treatment (all P < 0.05). After chemoradiotherapy, CT-FFR was lower and PCAT CT attenuation and LV myocardial ECV were higher than after chemotherapy. Twenty-four participants developed CTRCD. After adjustment by Heart Failure Association-International Cardio-Oncology Society risk in multivariable logistic regression analysis, baseline stenosis of the left anterior descending artery (LAD) (OR: 1.987 [95% CI: 1.322-2.768]; P = 0.021), left circumflex artery (LCX) (OR: 1.895 [95% CI: 1.281-2.802]; P = 0.031), and right coronary artery (RCA) (OR: 1.920 [95% CI: 1.405-2.811]; P = 0.028), and baseline CT-FFR of the LAD (OR: 3.425 [95% CI: 1.621-9.434]; P < 0.001), LCX (OR: 2.058 [95% CI: 1.030-5.076]; P = 0.006), and RCA (OR: 2.469 [95% CI: 1.232-6.944]; P = 0.004) were associated with CTRCD. CONCLUSIONS: Multiparameter coronary CTA contributes to comprehensive assessment of the coronary arteries and myocardium in patients with left BC receiving anthracycline with or without radiotherapy. Baseline coronary artery stenosis and CT-FFR might be imaging markers for predicting CTRCD in these patients.

7.
Front Oncol ; 14: 1396819, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974235

RESUMO

Background: Currently, there is no standard treatment for relapsed/refractory NK/T-cell lymphoma (NKTCL). Liposomal mitoxantrone (Lipo-MIT) showed good anti-tumor effect in patients with NKTCL, breaking the limitation of natural resistance of NKTCL to anthracyclines. To further improve the efficacy, we tried a combination therapy based on Lipo-MIT in patients with relapsed/refractory NKTCL. Methods: 12 patients with relapsed/refractory NKTCL were enrolled in this retrospective study, all of whom had previously received pegaspargase-based treatments. The salvage treatment was a combination regimen based on Lipo-MIT. The efficacy was evaluated after every two cycles. Results: 11 patients had stage IV NKTCL, and all but one patients had an NRI score of ≥3. The median previous lines of treatment was two (range, 1-4), and five patients were refractory to their last line of treatment. The best response rates were as follows: complete response (CR) in five (41.7%) patients, partial response in five (41.7%) patients, stable disease in one (8.3%) patient, and progressive disease in one (8.3%) patient. At a median follow-up of four months (range, 2-14), seven patients died, with a median PFS of five months and a median OS of seven months. The six-month PFS and OS rate was 44.4% and 52.1%, respectively. All patients had suffered from side effects, among which myelosuppression was most reported. Nine patients had grade three or more myelosuppression, and the median recovery time from myelosuppression was 14 days (2-35 days). Five patients had obvious skin hyperpigmentation, and the CR rate was significantly higher compared with those without skin hyperpigmentation (80% vs. 14.3%, p=0.023). Other side effects included liver insufficiency (N=4), coagulation dysfunction (N=4), acute pancreatitis (N=2), and immunotherapy-related adverse effects (irAEs, N=2). Conclusion: Combination therapy based on Lipo-MIT has a high remission rate for relapsed/refractory NKTCL, but the duration of remission needs to be further extended. Lipo-MIT has obvious myelosuppression toxicity, and active supportive therapy should be given when combined with other cytotoxic drugs.

8.
World J Gastrointest Surg ; 16(6): 1582-1591, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38983354

RESUMO

BACKGROUND: Intraoperative persistent hypotension (IPH) during pancreaticoduodenectomy (PD) is linked to adverse postoperative outcomes, yet its risk factors remain unclear. AIM: To clarify the risk factors associated with IPH during PD, ensuring patient safety in the perioperative period. METHODS: A retrospective analysis of patient records from January 2018 to December 2022 at the First Affiliated Hospital of Nanjing Medical University identified factors associated with IPH in PD. These factors included age, gender, body mass index, American Society of Anesthesiologists classification, comorbidities, medication history, operation duration, fluid balance, blood loss, urine output, and blood gas parameters. IPH was defined as sustained mean arterial pressure < 65 mmHg, requiring prolonged deoxyepinephrine infusion for > 30 min despite additional deoxyepinephrine and fluid treatments. RESULTS: Among 1596 PD patients, 661 (41.42%) experienced IPH. Multivariate logistic regression identified key risk factors: increased age [odds ratio (OR): 1.20 per decade, 95% confidence interval (CI): 1.08-1.33] (P < 0.001), longer surgery duration (OR: 1.15 per additional hour, 95%CI: 1.05-1.26) (P < 0.01), and greater blood loss (OR: 1.18 per 250-mL increment, 95%CI: 1.06-1.32) (P < 0.01). A novel finding was the association of arterial blood Ca2+ < 1.05 mmol/L with IPH (OR: 2.03, 95%CI: 1.65-2.50) (P < 0.001). CONCLUSION: IPH during PD is independently associated with older age, prolonged surgery, increased blood loss, and lower plasma Ca2+.

9.
Neurosurg Rev ; 47(1): 310, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985351

RESUMO

The relationship between in-hospital hemoglobin (Hb) drift and outcomes in patients undergoing surgical clipping for aneurysmal subarachnoid hemorrhage (aSAH) is not well studied. This study aims to investigate the association between Hb drift and mortality in this patient population. We conducted a cohort study encompassing adult patients diagnosed with aSAH who were admitted to a university hospital. These patients were stratified into distinct groups based on their Hb drift levels. We employed logistic and Cox proportional hazard models to assess the relationship between Hb drift and outcomes. Additionally, propensity score matching (PSM) was utilized to ensure comparability between patient groups. The discriminative performance of different models was evaluated using C-statistics, integrated discrimination improvement (IDI), and net reclassification improvement (NRI). Overall, our cohort comprised 671 patients, of whom 165 (24.6%) demonstrated an in-hospital Hb drift exceeding 25%. The analyses revealed elevated Hb drift was independently associated with higher likelihood of follow-up mortality (aOR: 3.29, 95% CI: 1.65 to 6.56; P = 0.001) and in-hospital mortality (aOR: 3.44, 95% CI: 1.55 to 7.63; P = 0.002). PSM analysis yielded similar results. Additionally, patients with Hb drift exhibited a notable decrease in survival rate compared to those without Hb drift (aHR: 3.99, 95% CI 2.30 to 6.70; P < 0.001). Furthermore, the inclusion of Hb drift significantly improved the C-statistic (P = 0.037), IDI (2.78%; P = 0.004) and NRI metrics (41.86%; P < 0.001) for mortality prediction. In summary, our results highlight that an in-hospital Hb drift exceeding 25% serves as an independent predictor of mortality in patients who have undergone surgical clipping for aSAH.


Assuntos
Hemoglobinas , Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/cirurgia , Masculino , Feminino , Hemoglobinas/análise , Pessoa de Meia-Idade , Adulto , Idoso , Mortalidade Hospitalar , Resultado do Tratamento , Estudos de Coortes , Procedimentos Neurocirúrgicos/métodos
10.
Sci Total Environ ; : 174693, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992364

RESUMO

Rewilding abandoned farmlands provides a nature-based climate solution via carbon (C) offsetting; however, the C-cycle-climate feedback in such restored ecosystems is poorly understood. Therefore, we conducted a 2-year field experiment in Loess Plateau, China, to determine the impacts of warming (~1.4 °C) and altered precipitation (±25 %, ±50 %, and ambient), alone or in concert on soil C pools and associated C fluxes. Experimental warming significantly enhanced soil respiration without affecting the ecosystem net C uptake and soil C storage; these variables tended to increase along the manipulated precipitation gradient. Their interactions increased ecosystem net C uptake (synergism) but decreased soil respiration and soil C accumulation (antagonism) compared with a single warming or altered precipitation. Additionally, most variables related to the C cycle tended to be more responsive to increased precipitation, but the ecosystem net C uptake responded intensely to warming and decreased precipitation. Overall, ecosystem net C uptake and soil C storage increased by 94.4 % and 8.2 %, respectively, under the warmer-wetter scenario; however, phosphorus deficiency restricted soil C accumulation under these climatic conditions. By contrast, ecosystem net C uptake and soil C storage decreased by 56.6 % and 13.6 %, respectively, when exposed to the warmer-drier climate, intensifying its tendency toward a C source. Therefore, the C sink function of semiarid abandoned farmland was unsustainable. Our findings emphasize the need for management of post-abandonment regeneration to sustain ecosystem C sequestration in the context of climate change, aiding policymakers in the development of C-neutral routes in abandoned regions.

11.
Dalton Trans ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995145

RESUMO

Density functional theory calculations have been performed to compare the HCHO decomposition on Co3O4(110)-A and (110)-B terminations. The results showed that the energy barriers of the two C-H bond cleavages of HCHO on the (110)-A termination were lower than those on the (110)-B termination, suggesting that the (110)-A termination had stronger HCHO decomposition ability than the (110)-B termination. Electronic structures revealed that the stronger HCHO decomposition ability of the (110)-A termination might be ascribed to the strong covalent bond between HCHO and the (110)-A termination, as well as the higher d-band center of Co3+ ions on the (110)-A termination. Furthermore, we proposed that the preparation of Co3O4 under oxygen-rich growth conditions was beneficial to HCHO decomposition because the (110)-A termination was more stable under oxygen-rich conditions.

12.
Helicobacter ; 29(4): e13079, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38984661

RESUMO

BACKGROUND: Eradicating Helicobacter pylori infection by bismuth quadruple therapy (BQT) is effective. However, the effect of BQT and subsequent fecal microbiota transplant (FMT) on the gut microbiota is less known. MATERIALS AND METHODS: This prospective randomized controlled trial was conducted at a tertiary hospital in China from January 2019 to October 2020, with the primary endpoints the effect of BQT on the gut microbiota and the effect of FMT on the gut microbiota after bismuth quadruple therapy eradication therapy. A 14-day BQT with amoxicillin and clarithromycin was administered to H. pylori-positive subjects, and after eradication therapy, patients received a one-time FMT or placebo treatment. We then collected stool samples to assess the effects of 14-day BQT and FMT on the gut microbiota. 16 s rDNA and metagenomic sequencing were used to analyze the structure and function of intestinal flora. We also used Gastrointestinal Symptom Rating Scale (GSRS) to evaluate gastrointestinal symptom during treatment. RESULTS: A total of 30 patients were recruited and 15 were assigned to either FMT or placebo groups. After eradication therapy, alpha-diversity was decreased in both groups. At the phylum level, the abundance of Bacteroidetes and Firmicutes decreased, while Proteobacteria increased. At the genus level, the abundance of beneficial bacteria decreased, while pathogenic bacteria increased. Eradication therapy reduced some resistance genes abundance while increased the resistance genes abundance linked to Escherichia coli. While they all returned to baseline by Week 10. Besides, the difference was observed in Week 10 by the diarrhea score between two groups. Compared to Week 2, the GSRS total score and diarrhea score decreased in Week 3 only in FMT group. CONCLUSIONS: The balance of intestinal flora in patients can be considerably impacted by BQT in the short term, but it has reverted back to baseline by Week 10. FMT can alleviate gastrointestinal symptoms even if there was no evidence it promoted restoration of intestinal flora.


Assuntos
Antibacterianos , Bismuto , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Infecções por Helicobacter , Helicobacter pylori , Humanos , Infecções por Helicobacter/terapia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Transplante de Microbiota Fecal/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Helicobacter pylori/efeitos dos fármacos , Adulto , Antibacterianos/uso terapêutico , Estudos Prospectivos , Bismuto/uso terapêutico , Quimioterapia Combinada , China , Amoxicilina/uso terapêutico , Claritromicina/uso terapêutico , Resultado do Tratamento , Idoso , Fezes/microbiologia
13.
Org Lett ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39024649

RESUMO

A chiral W-shaped fully π-extended double [7]helicene (ED7H) has been synthesized and fully characterized. It displays fluorescence emission (λem = 636 nm) with a quantum yield (Φf) of 0.10. In comparison to its X-shaped and monomict π-extended [7]helicene analogues, enantiopure W-shaped ED7H exhibited superior chiral optical characteristics, including distinct circular dichroism signals from 400 to 650 nm, a good dissymmetric emission factor |glum| of 4 × 10-3, and a circularly polarized luminescence brightness value BCPL of 42 M-1 cm-1.

14.
Heliyon ; 10(12): e33287, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39027455

RESUMO

The consequences caused by bacterial resistance are becoming more and more serious. The rate of antibiotic development is far behind the rate of bacterial resistance, so it is urgent to develop a new drug system. In this study, photoresponsive nanogels based on hyaluronic acid were prepared and loaded with ciprofloxacin as a model molecule. The results showed that the nanogels had the advantages of high stability and good cytocompatibility. The inhibition effect of drug-loaded nanogels after light irradiation on the growth of Staphylococcus aureus and Salmonella typhimurium was significantly better than that before light irradiation, and ciprofloxacin could be released on demand and in control. This strategy is of great significance to reduce the unnecessary use of antibiotics and weaken bacterial resistance.

15.
J Chem Phys ; 161(1)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38953446

RESUMO

Two-dimensional (2D) Sn-based perovskites exhibit significant potential in diverse optoelectronic applications, such as on-chip lasers and photodetectors. Yet, the underlying mechanism behind the frequently observed dual-peak emission in 2D Sn-based perovskites remains a subject of intense debate, and there is a lack of research on the carrier dynamics in these materials. In this study, we investigate these issues in a representative 2D Sn-based perovskite, namely, PEA2SnI4, through temperature-, excitation intensity-, angle-, and time-dependent photoluminescence studies. The results indicate that the high- and low-energy peaks originate from in-face and out-of-face dipole transitions, respectively. In addition, we observe an anomalous increase in the non-radiative recombination rate as temperature decreases. After ruling out enhanced electron-phonon coupling and Auger recombination as potential causes of the anomalous carrier dynamics, we propose that the significantly increased exciton binding energy (Eb) plays a decisive role. The increased Eb arises from enhanced electronic localization, a consequence of weakened lattice distortion at low temperatures, as confirmed by first-principles calculations and temperature-dependent x-ray diffraction measurements. These findings offer valuable insights into the electronic processes in the unique 2D Sn-based perovskites.

16.
Cancer Lett ; : 217117, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019144

RESUMO

Cancer cells rewire metabolism to sculpt the immune tumor microenvironment (TME) and propel tumor advancement, which intricately tied to post-translational modifications. Histone lactylation has emerged as a novel player in modulating protein functions, whereas little is known about its pathological role in pancreatic ductal adenocarcinoma (PDAC) progression. Employing a multi-omics approach encompassing bulk and single-cell RNA sequencing, metabolomics, ATAC-seq, and CUT&Tag methodologies, we unveiled the potential of histone lactylation in prognostic prediction, patient stratification and TME characterization. Notably, "LDHA-H4K12la-immuno-genes" axis has introduced a novel node into the regulatory framework of "metabolism-epigenetics-immunity," shedding new light on the landscape of PDAC progression. Furthermore, the heightened interplay between cancer cells and immune counterparts via Nectin-2 in liver metastasis with elevated HLS unraveled a positive feedback loop in driving immune evasion. Simultaneously, immune cells exhibited altered HLS and autonomous functionality across the metastatic cascade. Consequently, the exploration of innovative combination strategies targeting the metabolism-epigenetics-immunity axis holds promise in curbing distant metastasis and improving survival prospects for individuals grappling with challenges of PDAC.

17.
Sci Total Environ ; : 174812, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019268

RESUMO

Climate change is exacerbating drought in arid and semi-arid forest ecosystems worldwide. Soil microorganisms play a key role in supporting forest ecosystem services, yet their response to changes in aridity remains poorly understood. We present results from a study of 84 forests at four south-to-north Loess Plateau sites to assess how increases in aridity level (1- precipitation/evapotranspiration) shapes soil bacterial and fungal diversity and community stability by influencing community assembly. We showed that soil bacterial diversity underwent a significant downward trend at aridity levels >0.39, while fungal diversity decreased significantly at aridity levels >0.62. In addition, the relative abundance of Actinobacteria and Ascomycota increased with higher aridity level, while the relative abundance of Acidobacteria and Basidiomycota showed the opposite trend. Bacterial communities also exhibited higher similarity-distance decay rates across geographic and environmental gradients than did fungal communities. Phylogenetic bin-based community assembly analysis revealed homogeneous selection and dispersal limitation as the two dominant processes in bacterial and fungal assembly. Dispersal limitation of bacterial communities monotonically increased with aridity levels, whereas homogeneous selection of fungal communities monotonically decreased. Importantly, aridity also increased the sensitivity of microbial communities to environmental disturbance and potentially decreased community stability, as evidenced by greater community similarity-environmental distance decay rates, narrower habitat niche breadth, and lower microbial network stability. Our study provides new insights into soil microbial drought response, with implications on the sustainability of ecosystems under environmental stress.

18.
Huan Jing Ke Xue ; 45(7): 3789-3798, 2024 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-39022927

RESUMO

Guanzhong urban agglomeration has a good development foundation and great development potential, and it has a unique strategic position in the national all-round opening up pattern. In recent years, the problem of near-surface ozone (O3) in the Guanzhong Region has become increasingly prominent, which has become a bottleneck affecting the continuous improvement of air quality. In order to effectively prevent and control O3 pollution, this study analyzed the characteristics of annual, monthly, and daily changes in O3 concentration in the Guanzhong Region based on the environmental monitoring data from 2018 to 2021. A geo-detector was used to study the driving factors of the spatial differentiation of O3 concentration, and the sources of O3 were analyzed using a backward trajectory model and emission inventory construction. The results showed that the daily and monthly variation in O3 concentration in the Guanzhong Region were unimodal. The daily maximum value appeared at 15:00, the minimum value appeared at 07:00, the peak value of the monthly average appeared in June, and the valley value appeared in December. The O3 concentration was highest in summer, followed by that in spring, and the lowest in winter. The days of O3 exceeding the standard showed mainly mild pollution, and moderate and above pollution showed a trend of decreasing first and then increasing. The O3 concentration in the Guanzhong Region was mainly closely related to precursors and meteorological factors, and the explanatory power of the interaction of each factor was significantly greater than that of any single factor. The regional transport of O3 concentration in the Guanzhong Region was mainly affected by easterly airflow, followed by the northwest direction, with the potential source areas located mainly in Henan Province and Hubei Province. The main local sources of volatile organic compounds (VOCs) were solvent use sources, process sources, and mobile sources, and the main emission sources of nitrogen oxides (NOx) were mobile sources and industrial production combustion sources. The research results have a guiding significance for O3 joint prevention and control in the Guanzhong Region.

19.
Huan Jing Ke Xue ; 45(7): 4352-4360, 2024 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-39022979

RESUMO

Food waste is one of the important reservoirs of antibiotic resistance genes (ARGs), and its resource utilization has potential environmental risks. Anaerobic digestion (AD) technology can concurrently achieve resource recovery and ARGs removal, which is one of the popular resource technologies for food waste management. However, the removal efficiency of ARGs during the AD process is limited, and thus the safety of digestate for agricultural use is still questioned. Therefore, how to improve the performance of ARGs removal during the AD process is critical for efficient and environmentally friendly bioconversion of food waste. This study summarized the transmission pathways and mechanisms of ARGs in food waste; discussed the effects of different operation parameters on the transmission of ARGs in food waste during the AD process; described the research progress of exogenous addition of conductive materials, feedstock pretreatment, etc., strategies to enhance the removal of ARGs; and analyzed the migration regularity and removal mechanism of ARGs in food waste during the AD process, which mainly included microbial community structure evolution, mobile genetic element changes, and environmental factor changes. Finally, this study prospected the future improvement of methane yield and ARGs removal in the AD process of food waste based on the existing research.


Assuntos
Resistência Microbiana a Medicamentos , Anaerobiose , Resistência Microbiana a Medicamentos/genética , Eliminação de Resíduos/métodos , Reatores Biológicos/microbiologia , Alimentos , Biodegradação Ambiental , Perda e Desperdício de Alimentos
20.
Nature ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838737

RESUMO

Synaptic vesicles are organelles with a precisely defined protein and lipid composition1,2, yet the molecular mechanisms for the biogenesis of synaptic vesicles are mainly unknown. Here we discovered a well-defined interface between the synaptic vesicle V-ATPase and synaptophysin by in situ cryo-electron tomography and single-particle cryo-electron microscopy of functional synaptic vesicles isolated from mouse brains3. The synaptic vesicle V-ATPase is an ATP-dependent proton pump that establishes the proton gradient across the synaptic vesicle, which in turn drives the uptake of neurotransmitters4,5. Synaptophysin6 and its paralogues synaptoporin7 and synaptogyrin8 belong to a family of abundant synaptic vesicle proteins whose function is still unclear. We performed structural and functional studies of synaptophysin-knockout mice, confirming the identity of synaptophysin as an interaction partner with the V-ATPase. Although there is little change in the conformation of the V-ATPase upon interaction with synaptophysin, the presence of synaptophysin in synaptic vesicles profoundly affects the copy number of V-ATPases. This effect on the topography of synaptic vesicles suggests that synaptophysin assists in their biogenesis. In support of this model, we observed that synaptophysin-knockout mice exhibit severe seizure susceptibility, suggesting an imbalance of neurotransmitter release as a physiological consequence of the absence of synaptophysin.

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