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1.
J Food Sci ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38745380

ABSTRACT

This study aims to investigate the impact of four key factors, namely, temperature, water source, metal ion, and pH, on the stability of molecular chirality of dihydromyricetin (DMY) and proposed effective strategies for configuration protection. The findings reveal that temperatures exceeding 80°C could accelerate the racemization process of DMY, with a significant increase in racemization observed at 100°C. In addition, DMY exhibited heightened stability in ultrapure water as compared to various water sources, including pure water-1, pure water-2, mineral water, and running water. Notably, the presence of Fe2+ displayed an inhibitory effect on the racemization of DMY, whereas Mg2+, Ca2+, and Mn2+ showed a substantial promotional effect. Additionally, acidic conditions (pH < 5.0) were found to be protective for maintaining the stability of DMY, whereas alkaline conditions (pH > 9.0) were observed to be detrimental. Meanwhile, we first identified the presence of another pair of DMY isomers in this work.

2.
Bioresour Technol ; 402: 130800, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38734259

ABSTRACT

A sulfur-iron coupled ecological floating bed (EFB-SFe) was developed to enhance the denitrification capability of sulfur-based ecological floating beds (EFB-S). The denitrification performance, kinetic process and microbial community composition were explored. Results showed that sulfur-iron coupling effectively enhanced the denitrification performance of EFB, surpassing the sum of their individual effects. The average total nitrogen removal rate ranged from 1.56 to 4.56 g·m-2·d-1, with a removal efficiency of 22-84 %. The k value for the S + Fe group increased from 0.04 to 0.18 d-1 to 0.40-0.46 d-1 relative to the S group. The sulfur-iron coupling promoted the enrichment of denitrifying bacteria (Thiobacillus and Ferritrophicum). The denitrification genes in EFB-SFe were upregulated, being 12-22 times more abundant than in EFB-S. Sulfur and iron autotrophic denitrification were identified as the main nitrogen removal processes in EFB-SFe. Overall, sulfur-iron coupling showed the potential to enhance the denitrification capacity of EFB-S for treating low-pollution water.

3.
Bioresour Technol ; 400: 130690, 2024 May.
Article in English | MEDLINE | ID: mdl-38614150

ABSTRACT

Microbial enhanced oil recovery (EOR) has become the focus of oilfield research due to its low cost, environmental friendliness and sustainability. The degradation and EOR capacity of A. borkumensis through the production of bio-enzyme and bio-surfactant were first investigated in this study. The total protein concentration, acetylcholinesterase, esterase, lipase, alkane hydroxylase activity, surface tension, and emulsification index (EI) were determined at different culture times. The bio-surfactant was identified as glycolipid compound, and the yield was 2.6 ± 0.2 g/L. The nC12 and nC13 of crude oil were completely degraded, and more than 40.0 % of nC14-nC24 was degraded by by A. borkumensis. The results of the microscopic etching model displacement and core flooding experiments showed that emulsification was the main mechanism of EOR. A. borkumensis enhanced the recovery rate by 20.2 %. This study offers novel insights for the development of environmentally friendly and efficient oil fields.


Subject(s)
Alcanivoraceae , Biodegradation, Environmental , Petroleum , Surface-Active Agents , Surface-Active Agents/pharmacology , Surface-Active Agents/chemistry , Alcanivoraceae/metabolism , Petroleum/metabolism , Acetylcholinesterase/metabolism , Lipase/metabolism , Surface Tension , Emulsions
4.
Chemosphere ; 357: 141808, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38548086

ABSTRACT

Owing to the huge amounts and perishable character of vegetable wastes, composting is one of the best options for recycling vegetable wastes post-harvest. The initial moisture content (MC) is critical for optimizing composting process, but the effect of high MC in undehydrated vegetable wastes on composting was rarely reported. For this, the plant-scale windrows were prepared by mixing cauliflower waste and maize straw at different ratios to control initial MC of 70 % (T1-70) and 80 % (T2-80), respectively, and composted in winter. As composting progressed, substantial organic matter degradation, progressive humification, decreases in electrical conductivity and increases of pH and germination index (GI) were observed in both treatments. Nonetheless, T1-70 accelerated heating rate early during composting, prolonged high temperature period (>50 °C) by 30 d, thus increased the harmless level of composting, and significantly improved the humification of end-products compared to T2-80. Results also revealed that T1-70 activated more indigenous microbes and enhanced microbial interactions early during composting, with the fungi enriched in T1-70 playing an important role in accelerating the composting process. Remarkably, the difference in composting temperatures, humification degree, and microbial communities between the two treatments was most significant during the maturation phase. In this phase, MWH_CFBk5, Planktosalinus, Pseudopedobacter, and Luteimonas enriched in T1-70 were positively correlated with humification indices. It is suggested that the effect of initial MC, resulting from different ratios of vegetable waste to maize straw, on their composting was mediated by the composting temperature and microbial communities at low temperatures.


Subject(s)
Composting , Microbiota , Vegetables , Zea mays , Composting/methods , Soil/chemistry , Soil Microbiology , Temperature , Cold Temperature
5.
J Clin Nurs ; 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38528583

ABSTRACT

OBJECTIVES: (1) To describe existing tools to assess the burden of informal caregivers of people with cancer, (2) to describe how these tools have been validated and (3) to describe the areas of interest of existing assessment tool entries. BACKGROUND: The caregiver burden of informal caregivers of people with cancer greatly affects their lives. There is a wide variety of relevant assessment tools available, but there are no studies to help researchers to select tools. METHODS: A search was conducted using the keywords 'cancer', 'caregiver', 'burden' and 'scale' in Medline (PubMed), CINAHL and EMBASE to include articles that developed or applied tools to assess the burden on informal caregivers of cancer patients. Once eligible tools were identified, we searched their 'primary reference' studies. If the original scale was assessed in a population other than informal caregivers of cancer patients, we again searched for psychometric measures in the population of caregivers of cancer patients. RESULTS: This study retrieved 938 articles on developing or applying the informal caregiver burden instrument for cancer patients, including 42 scales. Internal consistency of the original scales ranged from 0.53 to 0.96. Nineteen scales initially developed to assess caregiver burden for patients with dementia, stroke and other disorders were later used for caregivers of cancer patients, eight of which have not yet been validated. Reclassifying all scale domains of concern revealed that scale assessments focused more on caregivers' physical health, emotional state and caregiving tasks. CONCLUSION: This review identifies many scales for assessing informal caregiver burden in cancer patients and gives scales recommended. However, a portion still needs to be validated. The development of a new scale proposes to be based on a theoretical framework and to consider dimensions for assessing support resources. IMPACT: What problem did the study address?: This paper collates assessment tools on the burden of informal carers of people with cancer. It also provides information on the applicable population, reliability and validity. What were the main findings?: 41 scales could be considered for use, eight of which have not been validated. The scales focus more on assessing caregivers' physical health, emotional state and caregiving tasks, and less on the dimension of support resources. Where and on whom will the research have an impact?: There are implications for informal carers of cancer patients in hospitals or in the community, as well as for relevant researchers. REPORTING METHOD: Retrieved with reference to systematic evaluation. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

6.
J Cell Mol Med ; 28(6): e18155, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38429911

ABSTRACT

We subtyped bladder cancer (BC) patients based on the expression patterns of endothelial cell (EC) -related genes and constructed a diagnostic signature and an endothelial cell prognostic index (ECPI), which are useful for diagnosing BC patients, predicting the prognosis of BC and evaluating drug sensitivity. Differentially expressed genes in ECs were obtained from the Tumour Immune Single-Cell Hub database. Subsequently, a diagnostic signature, a tumour subtyping system and an ECPI were constructed using data from The Cancer Genome Atlas and Gene Expression Omnibus. Associations between the ECPI and the tumour microenvironment, drug sensitivity and biofunctions were assessed. The hub genes in the ECPI were identified as drug candidates by molecular docking. Subtype identification indicated that high EC levels were associated with a worse prognosis and immunosuppressive effect. The diagnostic signature and ECPI were used to effectively diagnose BC and accurately assess the prognosis of BC and drug sensitivity among patients. Three hub genes in the ECPI were extracted, and the three genes had the closest affinity for doxorubicin and curcumin. There was a close relationship between EC and BC. EC-related genes can help clinicians diagnose BC, predict the prognosis of BC and select effective drugs.


Subject(s)
Urinary Bladder Neoplasms , Humans , Molecular Docking Simulation , Urinary Bladder Neoplasms/diagnosis , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/genetics , Endothelial Cells , Machine Learning , Immunotherapy , Tumor Microenvironment/genetics
7.
Talanta ; 272: 125824, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38422906

ABSTRACT

In this study, a self-powered biosensor based on an enzymatic biofuel cell was proposed for the first time for the ultrasensitive detection of soluble CD44 protein. The as-prepared biosensor was composed of the co-exist aptamer and glucose oxidase bioanode and bilirubin oxidase modified biocathode. Initially, the electron transfer from bioanode to biocathode was hindered due to the presence of the aptamer with high insulation, generating a low open-circuit voltage (EOCV). Once the target CD44 protein was present, it was recognized and captured by the aptamer at the bioanode, thus the interaction between the target CD44 protein and the immobilized aptamer caused the structural change at the surface of the electrode, which facilitated the transfer of electrons. The EOCV showed a good linear relationship with the logarithm of the CD44 protein concentrations in the range of 0.5-1000 ng mL-1 and the detection limit was 0.052 ng mL-1 (S/N = 3). The sensing platform showed excellent anti-interference performance and outstanding stability that maintained over 97% of original EOCV after 15 days. In addition, the relative standard deviation (1.40-1.96%) and recovery (100.23-101.31%) obtained from detecting CD44 protein in real-life blood samples without special pre-treatment indicated that the constructed biosensor had great potential for early cancer diagnosis.


Subject(s)
Bioelectric Energy Sources , Biosensing Techniques , Electron Transport , Glucose Oxidase/chemistry , Oligonucleotides/metabolism , Electrodes , Limit of Detection
8.
Bioresour Technol ; 396: 130442, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38354961

ABSTRACT

This work investigated the effect of oscillation-assisted hydrothermal process on extraction of caffeic acid and ferulic acid from sorghum straws. The results showed that the oscillation-assisted hydrothermal process efficiently improved extraction of caffeic acid and ferulic acid. The oscillation-assisted hydrothermal process resulted in the extraction rates of 1275.48 and 1822.64 mg/L.h for caffeic acid and ferulic acid, respectively. Moreover, the oscillation-assisted hydrothermal process exerted destructive effects on hemicellulose, lignin and the amorphous regions of cellulose, contributing to the release of caffeic acid and ferulic acid in pretreated sorghum straws. The scavenging activities for hydroxyl, 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid radicals of the caffeic acid and ferulic acid extracts obtained by the oscillation-assisted hydrothermal process were determined to be 83.69 %, 84.17 % and 88.45 %, respectively.


Subject(s)
Sorghum , Caffeic Acids , Coumaric Acids
9.
Water Res ; 253: 121285, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38354664

ABSTRACT

Considering the unsatisfied denitrification performance of carbon-limited wastewater in iron-based constructed wetlands (ICWs) caused by low electron transfer efficiency of iron substrates, utilization of plant-based conductive materials in-situ for improving the long-term reactivity of iron substrates was proposed to boost the Fe (III)/Fe (II) redox cycle thus enhance the nitrogen elimination. Here, we investigated the effects of withered Iris Pseudacorus biomass and its derived biochar on nitrogen removal for 165 days in ICWs. Results revealed that accumulate TN removal capacity in biochar-added ICW (BC-ICW) increased by 14.7 % compared to biomass-added ICW (BM-ICW), which was mainly attributed to the synergistic strengthening of iron scraps and biochar. The denitrification efficiency of BM-ICW improved by 11.6 % compared to ICWs, while its removal capacity declined with biomass consumption. Autotrophic and heterotrophic denitrifiers were enriched in BM-ICW and BC-ICW, especially biochar increased the abundance of electroactive species (Geobacter and Shewanella, etc.). An active iron cycle exhibited in BC-ICW, which can be confirmed by the presence of more liable iron minerals on iron scraps surface, the lowest Fe (III)/Fe (II) ratio (0.51), and the improved proportions of iron cycling genes (feoABC, korB, fhuF, TC.FEV.OM, etc.). The nitrate removal efficiency was positively correlated with the nitrogen, iron metabolism functional genes and the electron transfer capacity (ETC) of carbon materials (P < 0.05), indicating that redox-active carbon materials addition improved the iron scraps bioavailability by promoting electron transfer, thus enhancing the autotrophic nitrogen removal. Our findings provided a green perspective to better understand the redox properties of plant-based carbon materials in ICWs for deep bioremediation in-situ.


Subject(s)
Charcoal , Denitrification , Iron , Iron/chemistry , Wetlands , Biomass , Carbon , Oxidation-Reduction , Nitrogen
10.
PeerJ ; 12: e16811, 2024.
Article in English | MEDLINE | ID: mdl-38406275

ABSTRACT

Dipus sagitta is a major rodent found in arid environments and desert areas. They feed on plant seeds, young branches and some small insects, and have hibernating habits. Peak Dipus sagitta numbers impact the construction of the plant community in the environment, but also have a human impact as these rodents carry a variety of parasitic fleas capable of spreading serious diseases to humans. Based on 216 present distribution records of Dipus sagitta and seven environmental variables, this article simulates the potential distribution of Dipus sagitta during the Last Glacial Maximum, the mid-Holocene, the present and the future (2070s, RCP4.5, RCP8.5). This study also analyzes the geographic changes of the population distribution and evaluates the importance of climate factors by integrating contribution rate, replacement importance value and the jackknife test using the MaxEnt model. In this study, we opted to assess the predictive capabilities of our model using the receiver operating characteristic (ROC) and partial receiver operating characteristic (pROC) metrics. The findings indicate that the AUC value exceeds 0.9 and the AUC ratio is greater than 1, indicating superior predictive performance by the model. The results showed that the main climatic factors affecting the distribution of the three-toed jerboa were precipitation in the coldest quarter, temperature seasonality (standard deviation), and mean annual temperature. Under the two warming scenarios of the mid-Holocene and the future, there were differences in the changes in the distribution area of the three-toed jerboa. During the mid-Holocene, the suitable distribution area of the three-toed jerboa expanded, with a 93.91% increase in the rate of change compared to the Last Glacial Maximum. The size of the three-toed jerboa's habitat decreases under both future climate scenarios. Compared to the current period, under the RCP4.5 emission scenario, the change rate is -2.96%, and under the RCP8.5 emission scenario, the change rate is -7.41%. This indicates a trend of contraction in the south and expansion in the north. It is important to assess changes in the geographic population of Dipus sagitta due to climate change to formulate population control strategies of these harmful rodents and to prevent and control the long-distance transmission of zoonotic diseases.


Subject(s)
Climate Change , Ecosystem , Animals , Humans , Temperature , Rodentia , Zoonoses/epidemiology
11.
Chem Commun (Camb) ; 60(17): 2385-2388, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38321968

ABSTRACT

We present a red light-activated zincII bis(dipyrrin) symmetry breaking charge transfer (SBCT) architecture, showing a large molar absorption coefficient (ε = 15.4 × 104 M-1 cm-1), high reactive singlet oxygen generation efficiency (ΦΔ ≈ 0.8) and long-lived triplet state (τT = 150 µs) compared to the donor-acceptor analogue dipyrrin-BF2 complex, highlighting the superiority of the SBCT approach. For the first time, we demonstrated the potential of a SBCT scaffold in red-light-induced methyl methacrylate (MMA) polymerization, using a dual photocatalyst excitation approach.

12.
Cancer Lett ; 585: 216656, 2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38266804

ABSTRACT

Hormone receptor-positive breast cancer (HR+ BC) is known to be relatively insensitive to chemotherapy, and since chemotherapy has remained the major neoadjuvant therapy for HR+ BC, the undetermined mechanism of chemoresistance and how chemotherapy reshapes the immune microenvironment need to be explored by high-throughput technology. By using single-cell RNA sequencing and multiplexed immunofluorescence staining analysis of HR+ BC samples (paired pre- and post-neoadjuvant chemotherapy (NAC)), the levels of previously unrecognized immune cell subsets, including CD8+ T cells with pronounced expression of T-cell development (LMNA) and cytotoxicity (FGFBP2) markers, CD4+ T cells characterized by proliferation marker (ATP1B3) expression and macrophages characterized by CD52 expression, were found to be increased post-NAC, which were predictive of chemosensitivity and their antitumor function was also validated with in vitro experiments. In terms of immune checkpoint expression of CD8+ T cells, we found their changes were inconsistent post-NAC, that LAG3, VSIR were decreased, and PDCD1, HAVCR2, CTLA4, KLRC1 and BTLA were increased. In addition, we have identified novel genomic and transcriptional patterns of chemoresistant cancer cells, both innate and acquired, and have confirmed their prognostic value with TCGA cohorts. By shedding light on the ecosystem of HR+ BC reshaped by chemotherapy, our results uncover valuable candidates for predicting chemosensitivity and overcoming chemoresistance in HR+ BC.


Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Neoadjuvant Therapy/methods , CD8-Positive T-Lymphocytes/metabolism , Ecosystem , Sequence Analysis, RNA , Tumor Microenvironment , Sodium-Potassium-Exchanging ATPase/therapeutic use
13.
Biochem Biophys Res Commun ; 699: 149548, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38281329

ABSTRACT

Most chemotherapeutic drugs are potent and have a very narrow range of dose safety and efficacy, most of which can cause many side effects. Chemotherapy-induced peripheral neuropathy (CIPN) is the most common and serious side effect of chemotherapy for cancer treatment. However, its mechanism of action is yet to be fully elucidated. In the present study, we found that the treatment of the chemotherapy drug elemene induced hyperalgesia accompanied by anxiety-like emotions in mice based on several pain behavioral assays, such as mechanical allodynia and thermal hyperalgesia tests. Second, immunostaining for c-fos (a marker of activated neurons) further showed that elemene treatment activated several brain regions, including the lateral septum (LS), cingulate cortex (ACC), paraventricular nucleus of the thalamus (PVT), and dorsomedial hypothalamic nucleus (DMH), most notably in the GABAergic neurons of the lateral septum (LS). Finally, we found that both chemogenetic inhibition and apoptosis of LS neurons significantly reduced pain- and anxiety-like behaviors in mice treated with elemene. Taken together, these findings suggest that LS is involved in the regulation of elemene-induced chemotherapy pain and anxiety-like behaviors, providing a new target for the treatment of chemotherapy pain induced by elemene.


Subject(s)
Pain , Peripheral Nervous System Diseases , Sesquiterpenes , Mice , Animals , Peripheral Nervous System Diseases/chemically induced , GABAergic Neurons , Hyperalgesia/chemically induced , Hyperalgesia/drug therapy , Anxiety/chemically induced
14.
Eur J Pharmacol ; 966: 176340, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38244759

ABSTRACT

Hinokitiol is a natural bioactive tropolone derivative isolated from Chamaecyparis obtusa and Thuja plicata, which exhibits promising potential in terms of antioxidant and anti-inflammatory properties and possesses potent iron-binding capacity. In this study, we aimed to investigate the potential role of hinokitiol in protecting against ethanol-induced gastric injury and elucidate the underlying mechanism. Our results demonstrated that hinokitiol effectively attenuated hemorrhagic gastric lesions, epithelial cell loss, and inflammatory response in mice with ethanol-induced gastric injury. Intriguingly, we found that ethanol exposure affects iron levels both in vivo and in vitro. Moreover, the disturbed iron homeostasis was involved in the development of ethanol-induced injury. Iron depletion was found to enhance defense against ethanol-induced damage, while iron repletion showed the opposite effect. To further explore the role of iron sequestration in the protective effects of hinokitiol, we synthesized methylhinokitiol, a compound that shields the iron binding capacity of hinokitiol with a methyl group. Interestingly, this compound significantly diminishes the protective effect against ethanol-induced injury. These findings collectively demonstrated that hinokitiol could potentially be used to prevent or improve gastric injury induced by ethanol through regulating cellular iron homeostasis.


Subject(s)
Iron , Tropolone , Tropolone/analogs & derivatives , Mice , Animals , Tropolone/pharmacology , Ethanol/adverse effects , Anti-Inflammatory Agents , Monoterpenes/pharmacology , Monoterpenes/therapeutic use
15.
BMC Med Res Methodol ; 24(1): 16, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38254038

ABSTRACT

Lung cancer is a leading cause of cancer deaths and imposes an enormous economic burden on patients. It is important to develop an accurate risk assessment model to determine the appropriate treatment for patients after an initial lung cancer diagnosis. The Cox proportional hazards model is mainly employed in survival analysis. However, real-world medical data are usually incomplete, posing a great challenge to the application of this model. Commonly used imputation methods cannot achieve sufficient accuracy when data are missing, so we investigated novel methods for the development of clinical prediction models. In this article, we present a novel model for survival prediction in missing scenarios. We collected data from 5,240 patients diagnosed with lung cancer at the Weihai Municipal Hospital, China. Then, we applied a joint model that combined a BN and a Cox model to predict mortality risk in individual patients with lung cancer. The established prognostic model achieved good predictive performance in discrimination and calibration. We showed that combining the BN with the Cox proportional hazards model is highly beneficial and provides a more efficient tool for risk prediction.


Subject(s)
Lung Neoplasms , Humans , Lung Neoplasms/diagnosis , Bayes Theorem , Prognosis , Calibration , China/epidemiology
16.
Biodegradation ; 2024 Jan 27.
Article in English | MEDLINE | ID: mdl-38279065

ABSTRACT

Considerable efforts that isolate and characterize degrading bacteria for polycyclic aromatic hydrocarbons (PAHs) have focused on contaminated environments so far. Here we isolated three distinctive pyrene (PYR)-degrading bacteria from a paddy soil that was not contaminated with PAHs. These included a novel Bacillus sp. PyB-9 and efficient degraders, Shigella sp. PyB-6 and Agromyces sp. PyB-10. All three strains could utilize naphthalene, phenanthrene, anthracene, fluoranthene and PYR as sole carbon sources, and degraded PYR in a range of temperatures (27-37 °C) and pH (5-8). Strains PyB-6 and PyB-10 almost completely degraded 50 mg L-1 PYR within 15 days, and 75.5% and 98.9% of 100 mg L-1 PYR in 27 days, respectively. The kinetics of PYR biodegradation was well represented by the Gompertz model. Ten and twelve PYR metabolites were identified in PYR degradation process by strains PyB-6 and PyB-10, respectively. Chemical analyses demonstrated that the degradation mechanisms of PYR were the same for strains PyB-6 and PyB-10 with initial dioxygenation mainly on C-4,5 positions of PYR. The degradation of 4,5-phenanthrenedicarboxylic acid was branched to 4-phenanthrenecarboxylic acid pathway and 5-hydroxy-4-phenanthrenecarboxylic acid pathway, both of which played important roles in PYR degradation by strains PyB-6 and PyB-10. To our knowledge, Shigella sp. and Agromyces sp. were found for the first time to possess the capability for PAHs degradation. These findings contributed to upgrading the bank of microbial resource and knowledge on PAH biodegradation.

17.
Microbiol Spectr ; 12(1): e0229323, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38054717

ABSTRACT

IMPORTANCE: Polymyxins are considered the last line of defense against multidrug-resistant bacteria. The regulatory mechanism of polymyxin synthesis is poorly studied in Paenibacillus polymyxa. In this study, we found that Abh and AbrB3 negatively regulated, whereas Spo0A positively regulated polymyxin synthesis in P. polymyxa SC2. In addition, a regulatory relationship between Abh, AbrB3, and Spo0A was revealed, which regulate polymyxin synthesis via multiple regulatory mechanisms in P. polymyxa.


Subject(s)
Paenibacillus polymyxa , Paenibacillus , Polymyxins , Paenibacillus polymyxa/genetics , Paenibacillus/genetics
18.
Sci Total Environ ; 912: 169122, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38065502

ABSTRACT

Aboveground net primary productivity controls the amount of energy available to sustain all living organisms, and its sustainable provision relies on the stability of grassland ecosystems. Human activities leading to global changes, such as increased nitrogen (N) deposition and the more frequent occurrence of extreme precipitation events, with N addition increasing the sensitivity of ecosystem production stability to changes in the precipitation regime. However, whether N addition, in combination with seasonal precipitation increases or severe drought, affects ecosystem stability remains unclear. In this study, we conducted a six-year environmental change monitoring experiment in a semiarid grassland in northern China to test the effects of N addition, seasonal drought, and precipitation increases on the temporal stability of ecosystem productivity. Our study revealed that an interaction between drought and N addition reduced species diversity, species asynchrony, species stability, and thus ecosystem stability. These environmental change drivers (except for precipitation increase) induced a positive relationship between species asynchrony and diversity, whereas N addition interactively with drought and precipitation increase led to a negative relationship between diversity and species stability. Only N addition interactively with drought induced a positive species diversity-ecosystem stability relationship because lower species stability was overcome by increased species asynchrony. Our study is great importance to illustrate that production temporal stability tends to be inhibited with drought, though interactively with nutrient N addition. These findings highlight the primary role of asynchronous dynamics among species in modulating the effects of environmental change on diversity-stability relationships.


Subject(s)
Ecosystem , Grassland , Humans , Seasons , Droughts , Nitrogen
19.
Drug Deliv Transl Res ; 14(3): 788-801, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37755673

ABSTRACT

In this study, we synthesized a novel compound, agmatine-cholesterol conjugate (AG-Chol), to enhance the anti-tumor activity of drug-loaded liposomes. We replaced cholesterol with AG-Chol in preparing doxorubicin hydrochloride (DOX) liposomes by using an active loading method for DOX. We assessed the physical and chemical properties of the resulting AG-Liposomes and evaluated their efficacy in vitro and in vivo. The results showed that AG-Liposomes were stable with high encapsulation efficiency. Compared with the control liposomes, AG-Liposomes exhibited a slower drug release rate in the release medium at pH 6.8. The in vitro cell experiments demonstrated that AG-Liposomes had higher tumor cell uptake rate, stronger migration inhibition rate, higher apoptosis rate, better anti-clonogenic ability, and higher lysosome escape ability than the control liposomes. In vivo distribution results demonstrate that liposomes prepared with AG-Chol instead of cholesterol can significantly enhance their tumor targeting abilities and reduce their distribution to non-targeted sites. In vivo tumor suppression experiments showed that AG-Liposomes had a higher tumor suppression rate than the control liposomes without causing apparent toxicity to normal tissues, as evidenced by histological staining. Therefore, substituting cholesterol with AG-Chol in the preparation of liposomes can result in enhanced lysosome escape, improved tumor targeting, and increased efficacy of anti-tumor drugs.


Subject(s)
Agmatine , Antineoplastic Agents , Neoplasms , Humans , Liposomes/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Doxorubicin/pharmacology , Doxorubicin/chemistry , Drug Delivery Systems , Cholesterol/chemistry , Cell Line, Tumor
20.
Cell Prolif ; 57(2): e13551, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37743695

ABSTRACT

Busulfan is an antineoplastic, which is always accompanied with the abnormal of spermatogonia self-renewal and differentiation. It has been demonstrated that the omega-3 polyunsaturated fatty acids (PUFAs) benefits mature spermatozoa. However, whether omega-3 can protect endogenous spermatogonia and the detailed mechanisms are still unclear. Evaluate of spermatogenesis function (in vivo) were examined by histopathological analysis, immunofluorescence staining, and western blotting. The levels of lipid metabolites in testicular tissue were determined via liquid chromatography. We investigated the effect of lipid metabolites on Sertoli cells provided paracrine factors to regulate spermatogonia proliferation and differentiation using co-culture system. In our study, we showed that omega-3 PUFAs significantly improved the process of sperm production and elevated the quantity of both undifferentiated Lin28+ spermatogonia and differentiated c-kit+ spermatogonia in a mouse model where spermatogenic function was disrupted by busulfan. Mass spectrometry revealed an increase in the levels of several omega-3 metabolites in the testes of mice fed with omega-3 PUFAs. The eicosapentaenoic acid metabolite 12-hydroxyeicosapentaenoic acid (12-HEPE) up-regulated bone morphogenic protein 4 (BMP4) expression through GPR120-ERK1/2 pathway activation in Sertoli cells and restored spermatogonia proliferation and differentiation. Our study provides evidence that omega-3 PUFAs metabolite 12-HEPE effectively protects spermatogonia and reveals that GPR120 might be a tractable pharmacological target for fertility in men received chemotherapy or severe spermatogenesis dysfunction.


Subject(s)
Busulfan , Semen , Humans , Male , Mice , Animals , Busulfan/pharmacology , Busulfan/metabolism , Spermatogenesis/physiology , Spermatogonia , Spermatozoa , Testis/metabolism
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