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1.
Small ; 19(6): e2205933, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36461678

RESUMO

The rapid, simple and low-cost preparation of DNA micro-nano-architectures remain challenging in biosensing and therapy. Polymerase chain reaction (PCR)-driven DNA micro-nano-flowers are used to construct a nanosized baicalin-compressed-aptamer-nanodrug (bcaND) via one-pot assembly for targeted and synergistic anti-obesity. In the design, the tailored Adipo-8 (tAdi-8) overhang in the PCR amplicon displays anti-obesity targeting activity, while the baicalin loaded in the bcaND by embedding the amplicon plays a three-fold role as a lipid-lowering factor, bcaND size compressor, and uncoupling protein-1 (UCP1)-raised thermogenic activator. The ingenious bcaND represents an advanced multifunctional nanomaterial capable of adjusting the morphology at an optimal 400/1 molar ratio of Mg2+ to phosphate groups, compressing the size from 2.699 µm to 214.76 nm using 1 mg/mL baicalin at a temperature of 70 °C, an effective payload with amplicons of up to 98.94%, and a maximum baicalin load of 86.21 g/g DNA. Responsive release in acidic conditions (pH 5.0) occurs within 72 h, accelerating thermogenesis via UCP1 up-regulation by 2.5-fold in 3T3-L1-preadipocytes and 13.7-fold in the white-adipose-tissue (WAT) of mice, targeting adipocytes and visceral white adipose tissue. It plays an efficient synergistic role in obesity therapy in vitro and in vivo, providing a new direction for DNA self-assembly nanotechnology.


Assuntos
Nanopartículas , Obesidade , Camundongos , Animais , Obesidade/tratamento farmacológico , Obesidade/genética , Adipócitos , Tecido Adiposo Branco/fisiologia , Nanopartículas/uso terapêutico , Camundongos Endogâmicos C57BL
2.
Pestic Biochem Physiol ; 193: 105456, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37248022

RESUMO

Clarireedia spp. is a destructive phytopathogenic fungus that causes turf dollar spot of bent-grass, leading to widespread lawn death. In this study, we explored the antifungal capability of 6-pentyl-2H-pyran-2-one (6PP), a natural metabolite volatilized by microorganisms, which plays an important role in the biological control of turfgrass dollar spot. However, the mechanisms by which 6PP inhibits Clarireedia jacksonii remain unknown. In the present study, C. jacksonii mycelial growth was inhibited by the 6PP treatment and the 6PP treatment damaged cell membrane integrity, causing an increase in relative conduc-tivity. Furthermore, physiological and biochemistry assay showed that 6PP treatment can enhance reactive oxygen species (ROS) levels, malondialdehyde (MDA) content obviously increased with 6PP exposure, increased alchohol dehydrogenase (ADH) and depleted acetalde-hyde dehydrogenase (ALDH), and activated the activities of many antioxidant enzymes in C. jacksonii. Gen Ontology and Kyoto Encyclopedia of Genes and Genomes analysis revealed that some genes in C. jacksonii after 6PP treatment related to integrity of the cell wall and membrane, and oxidative stress were significantly downregulated. It is worth mentioning that the fatty acid degradation pathway is significantly upregulated, with an increase in ATP content and ATP synthase activity, which may promote fungal cell apoptosis. Moreover, we found that the expression of ABC transporters, and glutathione metabolism encoding genes were increased to respond to external stimuli. Taken together, these findings revealed the potential antifungal mechanism of 6PP against Clarireedia spp., which also provides a theoretical basis for the commercial utilization of 6PP as a green pesticide in the future.


Assuntos
Antifúngicos , Perfilação da Expressão Gênica , Antifúngicos/farmacologia , Oxirredutases , Trifosfato de Adenosina , Transcriptoma
3.
Appl Microbiol Biotechnol ; 106(9-10): 3669-3678, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35503471

RESUMO

Plectasin is a promising and potent antimicrobial peptide isolated from the fungus Pseudoplectania nigrella which has been heterologously expressed in various hosts. In this study, a four-copy cassette of plectasin was constructed via 2A peptide assembly to further increase its expression level in recombinant Pichia pastoris. The yeast transformant 4Ple-61 harboring four-copy cassette of plectasin could secrete 183.2 mg/L total protein containing 60.8% of plectasin at the flask level within 120 h, which was 2.3 times higher than that of the yeast transformant Ple-6 carrying one-copy cassette of plectasin. Western blot confirmed the significant peptide expression level in the transformant 4Ple-61. Furthermore, it yielded as high as 426.3 mg/L total protein within 120 h during a 5-L fermentation. The purified plectasin shows superior stability and good antimicrobial activity against conventional Staphylococcus aureus ATCC 26,001 and some food-borne antibiotic-resistant S. aureus strains with the MICs ranging from 8 to 32 µg/mL. Therefore, the strategy based on 2A peptide assembly can enhance the expression of plectasin and further expand its application prospect. KEY POINTS: • A yeast transformant 4Ple-61 with four-copy cassette of plectasin was constructed. • The plectasin level yield by the transformant 4Ple-61 was boosted by 2.3 times. • The plectasin showed good activity against food-borne antibiotic-resistant S. aureus.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Peptídeos , Saccharomycetales , Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Peptídeos/genética , Peptídeos/farmacologia , Proteínas Recombinantes/metabolismo , Saccharomycetales/genética , Saccharomycetales/metabolismo
4.
Adv Healthc Mater ; 13(11): e2303186, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38234201

RESUMO

Gene therapy has been one of potential strategies for the treatment of different diseases, where efficient and safe gene delivery systems are also extremely in need. Current lipid nanoparticles (LNP) technology highly depends on the packing and condensation of nucleic acids with amine moieties. Here, an attempt to covalently link two natural compounds, spermine and vitamin E, is made to develop self-assembled nucleic acid delivery systems. Among them, the spermine moieties specifically interact with the major groove of siRNA helix through salt bridge interaction, while vitamin E moieties are located around siRNA duplex. Such amphiphilic vitamin E-spermine/siRNA complexes can further self-assemble into nanocomplexes like multiblade wheels. Further studies indicate that these siRNA nanocomplexes with the neutrally charged surface of vitamin E can enter cells via caveolin/lipid raft mediated endocytosis pathway and bypass lysosome trapping. With these self-assembled delivery systems, efficient siRNA delivery is successfully achieved for Eg5 and Survivin gene silencing as well as DNA plasmid delivery. Further in vivo study indicates that VE-Su-Sper/DSPE-PEG2000/siSurvivin self-assembled nanocomplexes can accumulate in cancer cells and gradually release siRNA in tumor tissues and show significant antitumor effect in vivo. The self-assembled delivery system provides a novel strategy for highly efficient siRNA delivery.


Assuntos
Nanopartículas , RNA Interferente Pequeno , Espermina , Vitamina E , RNA Interferente Pequeno/química , Espermina/química , Animais , Humanos , Vitamina E/química , Nanopartículas/química , Camundongos , Linhagem Celular Tumoral , Camundongos Nus , Técnicas de Transferência de Genes , Camundongos Endogâmicos BALB C , Survivina/genética , Survivina/metabolismo , Neoplasias/terapia
5.
Diabetes ; 73(5): 682-700, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38394642

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is considered a risk factor for cardiovascular and cerebrovascular disease owing to its close association with coagulant disturbances. However, the precise biological functions and mechanisms that connect coagulation factors to NAFLD pathology remain inadequately understood. Herein, with unbiased bioinformatics analyses followed by functional testing, we demonstrate that hepatic expression of coagulation factor VII (FVII) decreases in patients and mice with NAFLD/nonalcoholic steatohepatitis (NASH). By using adenovirus-mediated F7-knockdown and hepatocyte-specific F7-knockout mouse models, our mechanistic investigations unveil a noncoagulant function of hepatic FVII in mitigating lipid accumulation and lipotoxicity. This protective effect is achieved through the suppression of fatty acid uptake, orchestrated via the AKT-CD36 pathway. Interestingly, intracellular FVII directly interacts with AKT and PP2A, thereby promoting their association and triggering the dephosphorylation of AKT. Therapeutic intervention through adenovirus-mediated liver-specific overexpression of F7 results in noteworthy improvements in liver steatosis, inflammation, injury, and fibrosis in severely afflicted NAFLD mice. In conclusion, our findings highlight coagulation factor FVII as a critical regulator of hepatic steatosis and a potential target for the treatment of NAFLD and NASH.


Assuntos
Fator VII , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Fator VII/genética , Fator VII/metabolismo , Ácidos Graxos/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
6.
Adv Sci (Weinh) ; : e2405955, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38924647

RESUMO

Obstructive sleep apnea syndrome (OSAS), characterized by chronic intermittent hypoxia (CIH), is an independent risk factor for aggravating non-alcoholic steatohepatitis (NASH). The prevailing mouse model employed in CIH research is inadequate for the comprehensive exploration of the impact of CIH on NASH development due to reduced food intake observed in CIH-exposed mice, which deviates from human responses. To address this issue, a pair-feeding investigation with CIH-exposed and normoxia-exposed mice is conducted. It is revealed that CIH exposure aggravates DNA damage, leading to hepatic fibrosis and inflammation. The analysis of genome-wide association study (GWAS) data also discloses the association between Eepd1, a DNA repair enzyme, and OSAS. Furthermore, it is revealed that CIH triggered selective autophagy, leading to the autophagic degradation of Eepd1, thereby exacerbating DNA damage in hepatocytes. Notably, Eepd1 liver-specific knockout mice exhibit aggravated hepatic DNA damage and further progression of NASH. To identify a therapeutic approach for CIH-induced NASH, a drug screening is conducted and it is found that Retigabine dihydrochloride suppresses CIH-mediated Eepd1 degradation, leading to alleviated DNA damage in hepatocytes. These findings imply that targeting CIH-mediated Eepd1 degradation can be an adjunctive approach in the treatment of NASH exacerbated by OSAS.

7.
IEEE Trans Neural Netw Learn Syst ; 34(10): 7515-7528, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35108210

RESUMO

The incomplete and imperfect essence of the battlefield situation results in a challenge to the efficiency, stability, and reliability of traditional intention recognition methods. For this problem, we propose a deep learning architecture that consists of a contrastive predictive coding (CPC) model, a variable-length long short-term memory network (LSTM) model, and an attention weight allocator for online intention recognition with incomplete information in wargame (W-CPCLSTM). First, based on the typical characteristics of intelligence data, a CPC model is designed to capture more global structures from limited battlefield information. Then, a variable-length LSTM model is employed to classify the learned representations into predefined intention categories. Next, a weighted approach to the training attention of CPC and LSTM is introduced to allow for the stability of the model. Finally, performance evaluation and application analysis of the proposed model for the online intention recognition task were carried out based on four different degrees of detection information and a perfect situation of ideal conditions in a wargame. Besides, we explored the effect of different lengths of intelligence data on recognition performance and gave application examples of the proposed model to a wargame platform. The simulation results demonstrate that our method not only contributes to the growth of recognition stability, but it also improves recognition accuracy by 7%-11%, 3%-7%, 3%-13%, and 3%-7%, the recognition speed by 6- 32× , 4- 18× , 13-* × , and 1- 6× compared with the traditional LSTM, classical FCN, OctConv, and OctFCN models, respectively, which characterizes it as a promising reference tool for command decision-making.

8.
Front Microbiol ; 14: 1147007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37799596

RESUMO

Background: The ruminant gastrointestinal contains numerous microbiomes that serve a crucial role in sustaining the host's productivity and health. In recent times, numerous studies have revealed that variations in influencing factors, including the environment, diet, and host, contribute to the shaping of gastrointestinal microbial adaptation to specific states. Therefore, understanding how host and environmental factors affect gastrointestinal microbes will help to improve the sustainability of ruminant production systems. Results: Based on a graphical analysis perspective, this study elucidates the microbial topology and robustness of the gastrointestinal of different ruminant species, showing that the microbial network is more resistant to random attacks. The risk of transmission of high-risk metagenome-assembled genome (MAG) was also demonstrated based on a large-scale survey of the distribution of antibiotic resistance genes (ARG) in the microbiota of most types of ecosystems. In addition, an interpretable machine learning framework was developed to study the complex, high-dimensional data of the gastrointestinal microbial genome. The evolution of gastrointestinal microbial adaptations to the environment in ruminants were analyzed and the adaptability changes of microorganisms to different altitudes were identified, including microbial transcriptional repair. Conclusion: Our findings indicate that the environment has an impact on the functional features of microbiomes in ruminant. The findings provide a new insight for the future development of microbial resources for the sustainable development in agriculture.

9.
Obesity (Silver Spring) ; 31(6): 1569-1583, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37203331

RESUMO

OBJECTIVE: Betaine-homocysteine methyltransferase (Bhmt) belongs to the family of methyltransferases and is involved in the one-carbon metabolic cycle, which is associated with the risk of diabetes and adiposity. This study aimed to explore whether Bhmt participated in the development of obesity or its associated diabetes, as well as the mechanism involved. METHODS: The expression levels of Bhmt were examined in stromal vascular fraction cells and mature adipocytes in obesity and nonobesity. Knockdown and overexpression of Bhmt in C3H10T1/2 cells were used to investigate Bhmt's function in adipogenesis. Bhmt's role in vivo was analyzed using an adenovirus-expressing system and a high-fat diet-induced obesity mouse model. RESULTS: Bhmt was highly expressed in stromal vascular fraction cells rather than mature adipocytes of adipose tissue and was upregulated in adipose tissue in obesity and C3H10T1/2-commited preadipocytes. Overexpression of Bhmt promoted adipocyte commitment and differentiation in vitro and exacerbated adipose tissue expansion in vivo, with a concomitant increase in insulin resistance, whereas Bhmt silencing exhibited opposite effects. Mechanistically, Bhmt-induced adipose expansion was mediated by stimulating the p38 MAPK/Smad pathway. CONCLUSIONS: The findings of this study highlight the obesogenic and diabetogenic role of adipocytic Bhmt and propose Bhmt as a promising therapeutic target for obesity and obesity-related diabetes.


Assuntos
Betaína-Homocisteína S-Metiltransferase , Resistência à Insulina , Animais , Camundongos , Adipócitos/metabolismo , Betaína-Homocisteína S-Metiltransferase/metabolismo , Obesidade/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
Food Chem ; 369: 130942, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34479010

RESUMO

2'-Fucosyllactose (2'-FL) is one of the nutrient ingredients in human milk, which has various beneficial health effects. α-l-fucosidase is a biotechnological tool for 2'-FL preparation. Here, a novel and efficient α-l-fucosidase OUC-Jdch16 from the fucoidan-digesting strain Flavobacterium algicola 12076 was heterologously expressed and applied to produce 2'-FL in vitro. OUC-Jdch16 belongs to glycoside hydrolases (GH) family 29 and exhibits the highest 4-nitrophenyl-α-l-fucopyranoside-hydrolyzing activity at 25 °C and pH 6.0. OUC-Jdch16 could catalyze the synthesis of 2'-FL via transferring the fucosyl residue from pNP-α-fucose to lactose. Under the optimal transfucosylation conditions, the yield of the transfucosylation product reached 84.82% and 92.15% (mol/mol) from pNP-α-fucose within 48 h and 120 h, respectively. Moreover, OUC-Jdch16 was capable of transferring the fucosyl residue to other glycosyl receptors with the generation of novel fucosylated compounds. This study demonstrated that OUC-Jdch16 could be a promising tool to prepare 2'-FL and other novel glycosides.


Assuntos
Oligossacarídeos , alfa-L-Fucosidase , Flavobacterium , Fucose , Humanos , Especificidade por Substrato , Trissacarídeos , alfa-L-Fucosidase/genética , alfa-L-Fucosidase/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-36012026

RESUMO

Since the beginning of the COVID-19 outbreak, confirmed and suspected cases of the disease have been increasing rapidly. The isolation of cases is one of the most effective methods for the control and containment of COVID-19 and has been rapidly popularized. Problems with isolation have gradually emerged, such as the inadequate allocation of isolation resources and the failure to properly resettle many of the suspected cases of the 2019-nCoV infection. In this paper, a self-isolation ecosystem of a rapid-deploying negative-pressurized "private car" is proposed for housing patients with 2019-nCoV infection, which could be lightweight, moderately sized and transparent to enable group supervision and communication. This "private car" isolation method aims to achieve self-isolation of patients and essentially solves the problem of where and how to isolate suspected cases while saving isolation resources and preventing the large-scale transmission of COVID-19.


Assuntos
COVID-19 , Automóveis , Surtos de Doenças/prevenção & controle , Ecossistema , Humanos , SARS-CoV-2
12.
Artigo em Inglês | MEDLINE | ID: mdl-36170386

RESUMO

Deep reinforcement learning (DRL) integrates the feature representation ability of deep learning with the decision-making ability of reinforcement learning so that it can achieve powerful end-to-end learning control capabilities. In the past decade, DRL has made substantial advances in many tasks that require perceiving high-dimensional input and making optimal or near-optimal decisions. However, there are still many challenging problems in the theory and applications of DRL, especially in learning control tasks with limited samples, sparse rewards, and multiple agents. Researchers have proposed various solutions and new theories to solve these problems and promote the development of DRL. In addition, deep learning has stimulated the further development of many subfields of reinforcement learning, such as hierarchical reinforcement learning (HRL), multiagent reinforcement learning, and imitation learning. This article gives a comprehensive overview of the fundamental theories, key algorithms, and primary research domains of DRL. In addition to value-based and policy-based DRL algorithms, the advances in maximum entropy-based DRL are summarized. The future research topics of DRL are also analyzed and discussed.

13.
ACS Synth Biol ; 10(3): 447-458, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33687208

RESUMO

Human milk oligosaccharide (HMO) is a key component of human milk carbohydrates and is closely related to the nutrition and health benefits of breastfeeding in infants. 2'-Fucosyllactose (2'-FL) is the most abundant fucosylated HMO, which has remarkable value in nutrition and medicine, such as suppressing pathogen infection, regulating intestinal flora, and boosting immunity. However, 2'-FL production via the method of extraction or chemical synthesis cannot meet its large demand, and as a result, environmentally friendly and efficient biotechnological approaches, including in vitro enzymatic synthesis and microbial cell factory production, have been developed and applied to its commercialized production. This review introduces, summarizes, and discusses the recent advances in the biotechnological production of 2'-FL. Furthermore, future research directions for the biotechnological production of 2'-FL as well as the strategies to further improve its concentration are highlighted and discussed.


Assuntos
Biotecnologia , Leite Humano/metabolismo , Trissacarídeos/biossíntese , Fucosiltransferases/química , Fucosiltransferases/genética , Fucosiltransferases/metabolismo , Humanos , Engenharia Metabólica , Saccharomyces cerevisiae/metabolismo , alfa-L-Fucosidase/química , alfa-L-Fucosidase/genética , alfa-L-Fucosidase/metabolismo
14.
Sci Rep ; 11(1): 9033, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33907200

RESUMO

Knot-free timber cultivation is an important goal of forest breeding, and lateral shoots affect yield and stem shape of tree. The purpose of this study was to analyze the molecular mechanism of lateral bud development by removing the apical dominance of Pinus massoniana young seedlings through transcriptome sequencing and identify key genes involved in lateral bud development. We analyzed hormone contents and transcriptome data for removal of apical dominant of lateral buds as well as apical and lateral buds of normal development ones. Data were analyzed using an comprehensive approach of pathway- and gene-set enrichment analysis, Mapman visualization tool, and gene expression analysis. Our results showed that the contents of auxin (IAA), Zea and strigolactone (SL) in lateral buds significantly increased after removal of apical dominance, while abscisic acid (ABA) decreased. Gibberellin (GA) metabolism, cytokinin (CK), jasmonic acid, zeatin pathway-related genes positively regulated lateral bud development, ABA metabolism-related genes basically negatively regulated lateral bud differentiation, auxin, ethylene, SLs were positive and negative regulation, while only A small number of genes of SA and BRASSINOSTEROID, such as TGA and TCH4, were involved in lateral bud development. In addition, it was speculated that transcription factors such as WRKY, TCP, MYB, HSP, AuxIAA, and AP2 played important roles in the development of lateral buds. In summary, our results provided a better understanding of lateral bud differentiation and lateral shoot formation of P. massoniana from transcriptome level. It provided a basis for molecular characteristics of side branch formation of other timber forests, and contributed to knot-free breeding of forest trees.


Assuntos
Pinus/crescimento & desenvolvimento , Pinus/genética , Brotos de Planta/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Pinus/citologia , Reguladores de Crescimento de Plantas/metabolismo , Brotos de Planta/citologia , Brotos de Planta/genética , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Fatores de Transcrição/genética
15.
J Agric Food Chem ; 69(18): 5363-5371, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33929187

RESUMO

Sulforaphene prepared from glucoraphenin by myrosinase is one of the main active ingredients of radish, which has various biological activities and brilliant potential for food and pharmaceutical applications. In this paper, a recombinant food-grade yeast transformant 20-8 with high-level myrosinase activity was constructed by over-expressing a myrosinase gene from Arabidopsis thaliana in Yarrowia lipolytica. The highest myrosinase activity produced by the transformant 20-8 reached 44.84 U/g dry cell weight when it was cultivated in a 10 L fermentor within 108 h. Under the optimal reaction conditions, 6.1 mg of sulforaphene was yielded from 1 g of radish seeds under the catalysis of the crude myrosinase preparation (4.95 U) at room temperature within 1.5 h. What is more is that when the whole yeast cells harboring myrosinase activity were reused 10 times, the sulforaphene yield still reached 92.53% of the initial level. Therefore, this efficient approach has broad application prospects in recyclable and large-scale preparation of sulforaphene.


Assuntos
Raphanus , Yarrowia , Glicosídeo Hidrolases , Isotiocianatos , Extratos Vegetais , Raphanus/genética , Sementes , Yarrowia/genética
16.
Commun Biol ; 4(1): 1212, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34675353

RESUMO

Pangolins are threatened placental mammals distributed in Africa and Asia. Many efforts have been undertaken in the last century to maintain pangolins in captivity, but only a few of them succeeded in maintaining and keeping this species in a controlled environment. This study reports the first systematic breeding of the Critically Endangered Malayan pangolin (Manis javanica) in captivity. Our captive breeding approach successfully improved the reproductive rate for both wild and captive-born female pangolins. From 2016 to 2020, we had 33 wild pangolins and produced 49 captive-born offspring spanning three filial generations. The female offspring further bred 18 offspring, of which 14 (78%) were conceived during the first time of cohabitation with males, and four offspring were conceived during the second cohabitation event, suggesting that they may practice copulation-induced ovulation. We observed that captive-born female pangolins could reach sexual maturity at 7-9 months (n = 4), and male pangolins could mate and successfully fertilise females at nine months age (n = 1). We also observed a female pangolin conceiving on the eighth day after parturition (the fifth day after the death of its pup). Our captive pangolins had a female-biased sex ratio of 1:0.5 at birth, unlike other known captive-born mammals. Also, captive-born pangolins were generally more viable after successful weaning and had a similar gestation length (~185 days) to wild pangolins. Most importantly, we report the first self-sustaining captive population of Malayan pangolins, and this species has an efficient reproduction strategy. These advances provide more comprehensive information for people to understand pangolins, and have implications for conserving endangered Malayan pangolins and providing scientific guidance to the management of other pangolin species.


Assuntos
Cruzamento , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Pangolins , Animais , Feminino , Masculino
17.
Braz. J. Pharm. Sci. (Online) ; 58: e181116, 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1374540

RESUMO

Abstract The aim of this study was to investigate the effect of TiO2/N-succinyl-chitosan composite (TiO2/ NSCS) photodynamic therapy (PDT), while considering the effects of various light sources on the activation of photosensitizer. The methyl thiazolyl tetrazolium assay was used to examine the cell survival rate of the cells. The results showed that glioma cell strain (U251) was the most sensitive cancer cell strain to TiO2/NSCS. When the concentration of TiO2/NSCS was between 0 and 800 μg·mL-1, there was no obvious cytotoxicity to normal liver cells (HL-7702) and U251 cells. During the PDT process, the photokilling effect of TiO2/NSCS on U251 cells under ultraviolet-A (UVA) light irradiation was stronger than that of pure TiO2, and its killing effects were positively correlated with concentration and irradiation time. In addition, both UVA and visible light could excite TiO2/ NSCS, which had significant killing effect on U251 cells. The results of acridine orange/ethidium bromide fluorescent double staining and Annexin V/propidium iodide double staining indicated that TiO2/NSCS under UVA and visible light irradiation could kill U251 cells by inducing apoptosis, and the apoptosis rate of TiO2/NSCS treatment groups was higher than that of TiO2 treatment groups. Therefore, TiO2/NSCS might be used as a potential photosensitizer in PDT.

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