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1.
Cancer Med ; 13(9): e6910, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38746969

RESUMO

BACKGROUND: Microsatellite instability-high (MSI-H) colorectal cancer (CRC) is known for its heightened responsiveness to immunotherapy. However, establishing robust predictive markers for immunotherapy efficacy remains imperative. This retrospective study aimed to elucidate the genetic landscape of MSI-H CRC and correlate these genetic alterations with immunotherapy outcomes in a cohort of 121 patients. METHODS: We analyzed clinical and molecular data from 121 patients with MSI-H CRC. We conducted a thorough genetic analysis of MSI-H CRC patients, with a specific emphasis on the APC, TP53, RAS, and MMR genes. We further analyzed the relationship between gene mutations and immunotherapy efficacy. The primary endpoints analyzed were objective response rate (ORR) and progression-free survival (PFS). All statistical analysis was conducted using SPSS26.0 and R 4.2.0 software. RESULTS: Our findings underscored the complexity of the genetic landscape in MSI-H CRC, shedding light on the intricate interplay of these genes in CRC development. Notably, mutations in MMR genes exhibited a distinctive pattern, providing insights into the underlying mechanisms of MSI-H. Furthermore, our results revealed correlations between specific genetic alterations and immunotherapy outcomes, with a particular focus on treatment response rates and progression-free survival. CONCLUSION: This study represents a significant step toward unraveling the genetic nuances of MSI-H CRC. The distinctive pattern of MMR gene mutations not only adds depth to our understanding of MSI-H CRC but also hints at potential avenues for targeted therapies. This research sets the stage for future investigations aimed at refining therapeutic strategies and improving outcomes for patients with MSI-H CRC.


Assuntos
Neoplasias Colorretais , Instabilidade de Microssatélites , Mutação , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/imunologia , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Imunoterapia/métodos , Idoso de 80 Anos ou mais , Intervalo Livre de Progressão , Biomarcadores Tumorais/genética , Reparo de Erro de Pareamento de DNA , Resultado do Tratamento
2.
Biotechnol Adv ; 73: 108354, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38588906

RESUMO

Thraustochytrids are marine microorganisms known for their fast growth and ability to store lipids, making them useful for producing polyunsaturated fatty acids (PUFAs), biodiesel, squalene, and carotenoids. However, the high cost of production, mainly due to expensive fermentation components, limits their wider use. A significant challenge in this context is the need to balance production costs with the value of the end products. This review focuses on integrating the efficient utilization of waste with Thraustochytrids fermentation, including the economic substitution of carbon sources, nitrogen sources, and fermentation water. This approach aligns with the 3Rs principles (reduction, recycling, and reuse). Furthermore, it emphasizes the role of Thraustochytrids in converting waste into lipid chemicals and promoting sustainable circular production models. The aim of this review is to emphasize the value of Thraustochytrids in converting waste into treasure, providing precise cost reduction strategies for future commercial production.

3.
Sci Total Environ ; 923: 171440, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38442763

RESUMO

Snowpack is closely related to vegetation green-up in water-limited ecosystems, and has effects on growing-season ecosystem processes. However, we know little about how changes in snowpack depth and melting timing affect primary productivity and plant community structure during the growing season. Here, we conducted a four-year snow manipulation experiment exploring how snow addition, snowmelt delay and their combination affect aboveground net primary productivity (ANPP), species diversity, community composition and plant reproductive phenology in seasonally snow-covered temperate grassland in northern China. Snow addition alone increased soil moisture and nutrient availability during early spring, while did not change plant community structure and ANPP. Instead, snowmelt delay alone postponed plant reproductive phenology, and increased ANPP, decreased species diversity and altered species composition. Grasses are more sensitive to changes in snowmelt timing than forbs, and early-flowering forbs showed a higher sensitivity compared to late-flowering forbs. The effect of snowmelt delay on ANPP and species diversity was offset by snow addition, probably because the added snow unnecessarily lengthens the snow-covering duration. The disparate effects of changes in snowpack depth and snowmelt timing necessitate their discrimination for more mechanistic understanding on the effects of snowpack changes on ecosystems. Our study suggests that it is essential to incorporate non-growing-season climate change events (in particular, snowfall and snowpack changes) to comprehensively disclose the effects of climate change on community structure and ecosystem functions.


Assuntos
Ecossistema , Pradaria , Plantas , Mudança Climática , Congelamento , Neve , Estações do Ano
4.
Bioresour Technol ; 398: 130532, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447618

RESUMO

Schizochytrium sp. hasreceived much attention for itsability to synthesize and accumulate high-level docosahexaenoic acid (DHA), which can reach nearly 40 % of total fatty acids. In this study, the titer of DHA in Schizochytrium sp. was successfully improved by enhancing DHA storage through overexpressing the diacylglycerol acyltransferase (ScDGAT2C) gene, as well as optimizing the supply of precursors and cofactors required for DHA synthesis by response surface methodology. Notably, malic acid, citric acid, and biotin showed synergistic and time-dependent effects on DHA accumulation. The maximum lipid and DHA titers of the engineered Schizochytrium sp. strain reached 84.28 ± 1.02 g/L and 42.23 ± 0.69 g/L, respectively, with the optimal concentration combination (1.62 g/L malic acid + 0.37 g/L citric acid + 8.28 mg/L biotin) were added 48 h after inoculation. This study provides an effective strategy for improving lipid and DHA production in Schizochytrium sp.


Assuntos
Ácidos Graxos , Malatos , Estramenópilas , Fermentação , Ácidos Docosa-Hexaenoicos , Biotina , Estramenópilas/genética , Ácido Cítrico
5.
Biotechnol Biofuels Bioprod ; 17(1): 32, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402213

RESUMO

BACKGROUND: Eicosapentaenoic acid (EPA) is widely used in the functional food and nutraceutical industries due to its important benefits to human health. Oleaginous microorganisms are considered a promising alternative resource for the production of EPA lipids. However, the storage of EPA in triglyceride (TG) becomes a key factor limiting its level. RESULTS: This study aimed to incorporate more EPA into TG storage through metabolic engineering. Firstly, key enzymes for TG synthesis, the diacylglycerol acyltransferase (DGAT) and glycerol-3-phosphate acyltransferase (GPAT) genes from Schizochytrium sp. HX-308 were expressed in Yarrowia lipolytica to enhance lipid and EPA accumulation. In addition, engineering the enzyme activity of DGATs through protein engineering was found to be effective in enhancing lipid synthesis by replacing the conserved motifs "HFS" in ScDGAT2A and "FFG" in ScDGAT2B with the motif "YFP". Notably, combined with lipidomic analysis, the expression of ScDGAT2C and GPAT2 enhanced the storage of EPA in TG. Finally, the accumulation of lipid and EPA was further promoted by identifying and continuing to introduce the ScACC, ScACS, ScPDC, and ScG6PD genes from Schizochytrium sp., and the lipid and EPA titer of the final engineered strain reached 2.25 ± 0.03 g/L and 266.44 ± 5.74 mg/L, respectively, which increased by 174.39% (0.82 ± 0.02 g/L) and 282.27% (69.70 ± 0.80 mg/L) compared to the initial strain, respectively. CONCLUSION: This study shows that the expression of lipid synthesis genes from Schizochytrium sp. in Y. lipolytica effectively improves the synthesis of lipids and EPA, which provided a promising target for EPA-enriched microbial oil production.

6.
Int J Hyperthermia ; 41(1): 2304264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38258583

RESUMO

OBJECTIVE: Long-term re-intervention after ultrasound-guided high intensity focused ultrasound (USgHIFU) ablation was reported, and the prediction of non-perfusion volume ratio (NPVR) in differently aged patients with uterine fibroids (UFs) was explored. MATERIALS AND METHODS: Patients with UFs who underwent USgHIFU ablation from January 2012 to December 2019 were enrolled and divided into < 40-year-old and ≥ 40-year-old groups. Cox regression was used to analyze the influencing factors of re-intervention rate, and receiver operating characteristic (ROC) curve was used to analyze the correlation between NPVR and re-intervention rate. RESULTS: A total of 2141 patients were enrolled, and 1558 patients were successfully followed up. The 10-year cumulative re-intervention rate was 21.9%, and the < 40-year-old group had a significantly higher rate than the ≥ 40-year-old group (30.8% vs. 19.1%, p < 0.001). NPVR was an independent risk factor in both two groups. When the NPVR reached 80.5% in the < 40-year-old group and 75.5% in the ≥ 40-year-old group, the risk of long-term re-intervention was satisfactory. CONCLUSION: The long-term outcome of USgHIFU is promising. The re-intervention rate is related to NPVR in differently aged patients. Young patients need a high NPVR to reduce re-intervention risk.


Assuntos
Leiomioma , Humanos , Idoso , Adulto , Perfusão , Leiomioma/diagnóstico por imagem , Leiomioma/cirurgia , Fatores de Risco
7.
Life Sci Alliance ; 7(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38290755

RESUMO

Accurate identification of neoantigens is important for advancing cancer immunotherapies. This study introduces Neoantigen MUlti-taSk Tower (NeoMUST), a model employing multi-task learning to effectively capture task-specific information across related tasks. Our results show that NeoMUST rivals existing algorithms in predicting the presentation of neoantigens via MHC-I molecules, while demonstrating a significantly shorter training time for enhanced computational efficiency. The use of multi-task learning enables NeoMUST to leverage shared knowledge and task dependencies, leading to improved performance metrics and a significant reduction in the training time. NeoMUST, implemented in Python, is freely accessible at the GitHub repository. Our model will facilitate neoantigen prediction and empower the development of effective cancer immunotherapeutic approaches.


Assuntos
Antígenos de Neoplasias , Neoplasias , Humanos , Neoplasias/terapia , Algoritmos
8.
Anticancer Drugs ; 35(2): 129-139, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37615540

RESUMO

Colorectal cancer (CRC) is one of the world's most common and deadly cancers. According to GLOBOCAN2020's global incidence rate and mortality estimates, CRC is the third main cause of cancer and the second leading cause of cancer-related deaths worldwide. The US Food and Drug Administration has approved auranofin for the treatment of rheumatoid arthritis. It is a gold-containing chemical that inhibits thioredoxin reductase. Auranofin has a number of biological activities, including anticancer activity, although it has not been researched extensively in CRC, and the mechanism of action on CRC cells is still unknown. The goal of this research was to see how Auranofin affected CRC cells in vivo and in vitro . The two chemical libraries were tested for drugs that make CRC cells more responsive. The CCK-8 technique was used to determine the cell survival rate. The invasion, migration, and proliferation of cells were assessed using a transwell test and a colony cloning experiment. An electron microscope was used to observe autophagosome formation. Western blotting was also used to determine the degree of expression of related proteins in cells. Auranofin's tumor-suppressing properties were further tested in a xenograft tumor model of human SW620 CRC cells. Auranofin dramatically reduced the occurrence of CRC by decreasing the proliferation, migration, and invasion of CRC cells, according to our findings. Through a mTOR-dependent mechanism, auranofin inhibits the epithelial-mesenchymal transition (EMT) and induces autophagy in CRC cells. Finally, in-vivo tests revealed that auranofin suppressed tumor growth in xenograft mice while causing no harm. In summary, auranofin suppresses CRC cell growth, invasion, and migration. Auranofin inhibits the occurrence and progression of CRC by decreasing EMT and inducing autophagy in CRC cells via a mTOR-dependent mechanism. These findings suggest that auranofin could be a potential chemotherapeutic medication for the treatment of human CRC.


Assuntos
Auranofina , Neoplasias Colorretais , Humanos , Animais , Camundongos , Auranofina/farmacologia , Auranofina/uso terapêutico , Linhagem Celular Tumoral , Serina-Treonina Quinases TOR/metabolismo , Neoplasias Colorretais/patologia , Autofagia , Transição Epitelial-Mesenquimal , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica
9.
Biotechnol Adv ; 70: 108298, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38048920

RESUMO

Polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and arachidonic acid (ARA), are beneficial for reducing blood cholesterol and enhancing memory. Traditional PUFA production relies on extraction from plants and animals, which is unsustainable. Thus, using microorganisms as lipid-producing factories holds promise as an alternative way for PUFA production. Several oleaginous microorganisms have been successfully industrialized to date. These can be divided into universal and specialized hosts according to the products range of biosynthesis. The Yarrowia lipolytica is universal oleaginous host that has been engineered to produce a variety of fatty acids, such as γ-linolenic acid (GLA), EPA, ARA and so on. By contrast, the specialized host are used to produce only certain fatty acids, such as ARA in Mortierella alpina, EPA in Nannochloropsis, and DHA in Thraustochytrids. The metabolic engineering and fermentation strategies for improving PUFA production in universal and specialized hosts are different, which is the subject of this review. In addition, the widely applicable strategies for microbial lipid production that are not specific to individual hosts were also reviewed.


Assuntos
Ácidos Graxos Insaturados , Ácidos Graxos , Animais , Ácido Eicosapentaenoico/metabolismo , Engenharia Metabólica , Ácidos Docosa-Hexaenoicos/metabolismo
11.
Bioresour Technol ; 394: 130250, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154734

RESUMO

Schizochytrium sp., a microalga with high lipid content, holds the potential for co-producing docosahexaenoic acid (DHA) and carotenoids. In this study, the ability of Schizochytrium sp. to naturally produce carotenoids was systematically explored. Further, by enhancing the precursor supply of geranylgeranyl diphosphate, regulating carbon source through sugar limitation fermentation and employing a combination of response surface methodology and artificial neural networks to precisely optimize nitrogen sources, a new record of 43-fold increase in ß-carotene titer was achieved in the 5L bioreactor (653.2 mg/L). Meanwhile, a high DHA content was maintained (13.4 g/L). Furthermore, the use of corn stover hydrolysate has effectively lowered the production costs of carotenoid and DHA while sustaining elevated production levels (with total carotenoid titer and DHA titer reached 502.0 mg/L and 13.2 g/L, respectively). This study offers an efficient and cost-effective method for the co-production of carotenoid and DHA in Schizochytrium sp..


Assuntos
Ácidos Docosa-Hexaenoicos , Estramenópilas , Fermentação , Carotenoides , Reatores Biológicos , Engenharia Genética
12.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38040492

RESUMO

Accurate prediction of TCR-pMHC binding is important for the development of cancer immunotherapies, especially TCR-based agents. Existing algorithms often experience diminished performance when dealing with unseen epitopes, primarily due to the complexity in TCR-pMHC recognition patterns and the scarcity of available data for training. We have developed a novel deep learning model, 'TCR Antigen Binding Recognition' based on BERT, named as TABR-BERT. Leveraging BERT's potent representation learning capabilities, TABR-BERT effectively captures essential information regarding TCR-pMHC interactions from TCR sequences, antigen epitope sequences and epitope-MHC binding. By transferring this knowledge to predict TCR-pMHC recognition, TABR-BERT demonstrated better results in benchmark tests than existing methods, particularly for unseen epitopes.


Assuntos
Algoritmos , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos de Linfócitos T/genética , Ligação Proteica , Epitopos/metabolismo , Aprendizado de Máquina
13.
Front Oncol ; 13: 1174788, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023207

RESUMO

Purpose: The prognosis of liver cancer remains unfavorable nowadays, making the search for predictive biomarkers of liver cancer prognosis of paramount importance to guide clinical diagnosis and treatment. This study was conducted to explore more prognostic markers for most HCC. Patients and methods: A total of 330 patients were enrolled in this study according to the inclusion and exclusion criteria. Follow-up data were collected for all patients until the cutoff date of the study, February 2023. In addition, patient outcomes were assessed with progression-free survival (PFS) and overall survival (OS). All statistical analysis was conducted using R 4.2.0 software. Results: Univariate analysis illustrated that the GD [the product of gamma-glutamyl transpeptidase (GGT) concentration and D-dimer concentration, GD=GGT*D-dimer] levels were related to PFS (p<0.05) and OS (p<0.05). Kaplan-Meier survival curves and log-rank tests indicated a significant difference among different levels of GD (p<0.001). Multivariate analysis demonstrated GD as an independent prognostic factor for HCC. The C-indexes of nomogram were 0.77 and 0.76 in the training or validation cohort, respectively. Area Under the Curve (AUC) of 1-, 2-, 3-, and 4-year OS showed satisfactory accuracy, and the calibration curve illustrated brilliant consistence between the ideal and predicted values. Conclusions: Herein, it was demonstrated that GD was an independent prognostic factor for HCC and revealed the potential to predict the PFS and OS in patients with HCC. Moreover, the nomogram based on GD illustrated a satisfactory prediction ability in comparison to other models without GD.

14.
Commun Biol ; 6(1): 1102, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907587

RESUMO

Currently, studies of ancient faunal community networks have been based mostly on uniformitarian and functional morphological evidence. As an important source of data, taphonomic evidence offers the opportunity to provide a broader scope for understanding palaeoecology. However, palaeoecological research methods based on taphonomic evidence are relatively rare, especially for body fossils in lacustrine sediments. Such fossil communities are not only affected by complex transportation and selective destruction in the sedimentation process, they also are strongly affected by time averaging. Historically, it has been believed that it is difficult to study lacustrine entombed fauna by a small-scale quadrat survey. Herein, we developed a software, the TaphonomeAnalyst, to study the associational network of lacustrine entombed fauna, or taphocoenosis. TaphonomeAnalyst allows researchers to easily perform exploratory analyses on common abundance profiles from taphocoenosis data. The dataset for these investigations resulted from fieldwork of the latest Middle Jurassic Jiulongshan Formation near Daohugou Village, in Ningcheng County of Inner Mongolia, China, spotlighting the core assemblage of the Yanliao Fauna. Our data included 27,000 fossil specimens of animals from this deposit, the Yanliao Fauna, whose analyses reveal sedimentary environments, taphonomic conditions, and co-occurrence networks of this highly studied assemblage, providing empirically robust and statistically significant evidence for multiple Yanliao habitats.


Assuntos
Ecossistema , Fósseis , Animais , China
15.
Ann Gen Psychiatry ; 22(1): 47, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996851

RESUMO

BACKGROUND: Major depressive disorder (MDD) poses a significant social and economic burden worldwide. Identifying exposures, risk factors, and biological mechanisms that are causally connected to MDD can help build a scientific basis for disease prevention and development of novel therapeutic approaches. METHODS: In this systematic review, we assessed the evidence for causal relationships between putative causal risk factors and MDD from Mendelian randomization (MR) studies, following PRISMA. We assessed methodological quality based on key elements of the MR design: use of a full instrumental variable analysis and validation of the three key MR assumptions. RESULTS: We included methodological details and results from 52 articles. A causal link between lifestyle, metabolic, inflammatory biomarkers, particular pathological states and MDD is supported by MR investigations, although results for each category varied substantially. CONCLUSIONS: While this review shows how MR can offer useful information for examining prospective treatment targets and better understanding the pathophysiology of MDD, some methodological flaws in the existing literature limit reliability of results and probably underlie their heterogeneity. We highlight perspectives and recommendations for future works on MR in psychiatry.

16.
Int J Biol Macromol ; 253(Pt 8): 127625, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37884233

RESUMO

Exopolysaccharide (EPS), a bioproduct of lactic acid bacteria (LAB), has various health-promoting biological activities that may be beneficial for cancer therapy. This in vivo and in vitro study aimed to elucidate the anti-colorectal cancer (CRC) capacity of a homopolysaccharide EPS obtained from Weissella confusa J4-1 (EPSJ4-1) isolated from the faeces of healthy infants. We confirmed that EPSJ4-1 contained glucose and effectively suppressed the proliferation, migration, and invasion of CRC cells. EPSJ4-1 treatment significantly retarded the growth of HT-29 tumour xenografts without causing cytotoxicity to normal organs. EPSJ4-1 exerts an inhibitory effect on cell proliferation by inducing G0/G1 phase cell cycle arrest in CRC cells. Furthermore, EPSJ4-1 upregulated p21 levels and downregulated mutant p53 and cyclin kinase 2 levels. This is the first study to demonstrate the antitumour effects of EPS from W. confusa on CRC via cell cycle arrest and inhibition of cell migration and invasion, suggesting that EPSJ4-1 has the potential to be developed as a nutraceutical or pharmaceutical drug to prevent and treat CRC.


Assuntos
Neoplasias Colorretais , Weissella , Lactente , Humanos , Pontos de Checagem do Ciclo Celular , Weissella/metabolismo , Proliferação de Células , Neoplasias Colorretais/metabolismo , Ciclo Celular
17.
Leuk Lymphoma ; 64(13): 2113-2122, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37732615

RESUMO

We retrospectively analyzed the outcomes of 136 consecutive patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) at our center. Among them, 76 cases used hypomethylating agents (decitabine, n = 40; azacitidine, n = 36) as post-transplant maintenance therapy, whereas 60 contemporaneous patients did not adopt maintenance therapy. The 3-year incidences of relapse in two groups were 16.6% and 39.2% (p = .001). The 3-year OS and DFS in maintenance group were 84.0% and 78.6%, which were remarkably improved than in control group (60.0% and 58.0%) (p = .004, p = .011). Moreover, the 3-year relapse rates for patients receiving decitabine and azacitidine therapy were 8.5% and 25.0%, respectively (p = .019). Patients utilizing decitabine had more common possibility of grade 3-4 neutropenia than azacitidine (20.0% vs. 2.8%, p = .031). These results indicate that maintenance therapies using hypomethylating agents could reduce the risk of post-transplant recurrence, resulting into remarkable superior survival. Decitabine might lower relapse after allo-HSCT with somewhat more severe myelosuppression when being compared to azacitidine.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Decitabina/uso terapêutico , Estudos Retrospectivos , Transplante Homólogo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Azacitidina/efeitos adversos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Recidiva
18.
Biotechnol J ; 18(12): e2300314, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37596914

RESUMO

Docosahexaenoic acid (DHA) as one of ω-3 polyunsaturated fatty acids (PUFAs), plays a key role in brain development, and is widely used in food additives and the pharmaceutical industry. Schizochytrium sp. is often considered as a satisfactory strain for DHA industrialization. The aim of this study was to assess the feasibility of phosphopantetheinyl transferase (PPTase) and ω-3 fatty acid desaturase (FAD) for regulating DHA content in Schizochytrium sp. PPTase is essential to activate the polyketide-like synthase (PKS) pathway, which can transfer apo-acyl-carrier protein (apo-ACP) into holo-ACP, and plays a key role in DHA synthesis. Moreover, DHA and docosapentaenoic acid (DPA) are synthesized by the PKS pathway simultaneously, so high DPA synthesis limits the increase of DHA content. In addition, the detailed mechanisms of PKS pathway have not been fully elucidated, so it is difficult to improve DHA content by modifying PKS. However, ω-3 FAD can convert DPA into DHA, and it is the most direct and effective way to increase DHA content and reduce DPA content. Based on this, PPTase was overexpressed to enhance the synthesis of DHA by the PKS pathway, overexpressed ω-3 FAD to convert the co-product of the PKS pathway into DHA, and co-overexpressed PPTase and ω-3 FAD. With these strategies, compared with wild type, the final lipid, and DHA titer were 92.5 and 51.5 g L-1 , which increased by 46.4% and 78.1%, respectively. This study established an efficient DHA production strain, and provided some feasible strategies for industrial DHA production in Schizochytrium sp.


Assuntos
Ácidos Docosa-Hexaenoicos , Estramenópilas , Ácidos Docosa-Hexaenoicos/metabolismo , Estramenópilas/genética , Estramenópilas/metabolismo , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Policetídeo Sintases/metabolismo
19.
J Agric Food Chem ; 71(25): 9847-9855, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37326390

RESUMO

Odd chain fatty acids (OCFAs) are high-value-added compounds with great application in the field of food and medicine. As an oleaginous microorganism, Schizochytrium sp. has the potential to produce OCFAs efficiently. Propionyl-CoA is used as a precursor to synthesize OCFAs through the fatty acid synthetase (FAS) pathway, so its flow direction determines the yield of OCFAs. Here, different substrates were assessed to promote propionyl-CoA supply for OCFA accumulation. Moreover, the methylmalonyl-CoA mutase (MCM) was identified as the key gene responsible for propionyl-CoA consumption, which promotes the propionyl-CoA to enter into the tricarboxylic acid cycle rather than the FAS pathway. As one of the classic B12-dependent enzymes, the activity of MCM can be inhibited in the absence of B12. As expected, the OCFA accumulation was greatly increased. However, the removal of B12 caused growth limitation. Furthermore, the MCM was knocked out to block the consumption of propionyl-CoA and to maintain cell growth; results showed that the engineered strain achieved the OCFAs titer of 2.82 g/L, which is 5.76-fold that of wild type. Last, a fed-batch co-feeding strategy was developed, resulting in the highest reported OCFAs titer of 6.82 g/L. This study provides guidance for the microbial production of OCFAs.


Assuntos
Acil Coenzima A , Ácidos Graxos , Ácidos Graxos/metabolismo , Acil Coenzima A/metabolismo , Ciclo do Ácido Cítrico
20.
Ann Hematol ; 102(7): 1745-1759, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37233774

RESUMO

The classic BCR-ABL1-negative myeloproliferative neoplasm (MPN) is a highly heterogeneous hematologic tumor that includes three subtypes, namely polycythemia vera (PV), essential thrombocytosis (ET), and primary myelofibrosis (PMF). Despite having the same JAK2V617F mutation, the clinical manifestations of these three subtypes of MPN differ significantly, which suggests that the bone marrow (BM) immune microenvironment may also play an important role. In recent years, several studies have shown that peripheral blood monocytes play an important role in promoting MPN. However, to date, the role of BM monocytes/macrophages in MPN and their transcriptomic alterations remain incompletely understood. The purpose of this study was to clarify the role of BM monocytes/macrophages in MPN patients with the JAK2V617F mutation. MPN patients with the JAK2V617F mutation were enrolled in this study. We investigated the roles of monocytes/macrophages in the BM of MPN patients, using flow cytometry, monocyte/macrophage enrichment sorting, cytospins and Giemsa-Wright staining, and RNA-seq. Pearson correlation coefficient analysis was also used to detect the correlation between BM monocytes/macrophages and the MPN phenotype. In the present study, the proportion of CD163+ monocytes/macrophages increased significantly in all three subtypes of MPN. Interestingly, the percentages of CD163+ monocytes/macrophages are positively correlated with HGB in PV patients and PLT in ET patients. In contrast, the percentages of CD163+ monocytes/macrophages are negatively correlated with HGB and PLT in PMF patients. It was also found that CD14+CD16+ monocytes/macrophages increased and correlated with MPN clinical phenotypes. RNA-seq analyses demonstrated that the transcriptional expressions of monocytes/macrophages in MPN patients are relatively distinct. Gene expression profiles of BM monocytes/macrophages suggest a specialized function in support of megakaryopoiesis in ET patients. In contrast, BM monocytes/macrophages yielded a heterogeneous status in the support or inhibition of erythropoiesis. Significantly, BM monocytes/macrophages shaped an inflammatory microenvironment, which, in turn, promotes myelofibrosis. Thus, we characterized the roles of increased monocytes/macrophages in the occurrence and progression of MPNs. Our findings of the comprehensive transcriptomic characterization of BM monocytes/macrophages provide important resources to serve as a basis for future studies and future targets for the treatment of MPN patients.


Assuntos
Neoplasias da Medula Óssea , Transtornos Mieloproliferativos , Policitemia Vera , Trombocitemia Essencial , Humanos , Medula Óssea/patologia , Monócitos/patologia , Transtornos Mieloproliferativos/genética , Policitemia Vera/genética , Mutação , Neoplasias da Medula Óssea/patologia , Trombocitemia Essencial/genética , Janus Quinase 2/genética , Microambiente Tumoral
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