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1.
Mol Cell Proteomics ; 23(2): 100720, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38246484

RESUMO

Nonobstructive azoospermia is the leading cause of male infertility. Abnormal levels of transmembrane protein 225 (TMEM225), a testis-specific protein, have been found in patients with nonobstructive azoospermia, suggesting that TMEM225 plays an essential role in male fertility. Here, we generated a Tmem225 KO mouse model to explore the function and mechanism of TMEM225 in male reproduction. Male Tmem225 KO mice were infertile. Surprisingly, Tmem225 deletion did not affect spermatogenesis, but TMEM225-null sperm exhibited abnormalities during epididymal maturation, resulting in reduced sperm motility and an abnormal hairpin-loop configuration. Furthermore, proteomics analyses of cauda sperm revealed that signaling pathways related to mitochondrial function, the glycolytic pathway, and sperm flagellar morphology were abnormal in Tmem225 KO sperm, and spermatozoa lacking TMEM225 exhibited high reactive oxygen species levels, reduced motility, and flagellar folding, leading to typical asthenospermia. These findings suggest that testicular TMEM225 may control the sperm maturation process by regulating the expression of proteins related to mitochondrial function, glycolysis, and sperm flagellar morphology in epididymal spermatozoa.


Assuntos
Azoospermia , Humanos , Masculino , Camundongos , Animais , Azoospermia/metabolismo , Maturação do Esperma , Motilidade dos Espermatozoides , Sêmen , Espermatozoides/metabolismo , Testículo/metabolismo , Espermatogênese , Fertilidade , Camundongos Knockout
2.
FASEB J ; 38(1): e23361, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085152

RESUMO

Oocyte meiotic prophase I (MI) is an important event in female reproduction. Breast cancer amplified sequence 2 (BCAS2) is a component of the spliceosome. Previous reports have shown that BCAS2 is critical in male germ cell meiosis, oocyte development, and early embryo genome integrity. However, the role of BCAS2 in oocyte meiosis has not been reported. We used Stra8-GFPCre mice to knock out Bcas2 in oocytes during the pachytene phase. The results of fertility tests showed that Bcas2 conditional knockout (cKO) in oocytes results in infertility in female mice. Morphological analysis showed that the number of primordial follicles in the ovaries of 2-month-old (M) mice was significantly reduced and that follicle development was blocked. Further analysis showed that the number of primordial follicles decreased and that follicle development was slowed in 7-day postpartum (dpp) ovaries. Moreover, primordial follicles undergo apoptosis, and DNA damage cannot be repaired in primary follicle oocytes. Meiosis was abnormal; some oocytes could not reach the diplotene stage, and more oocytes could not develop to the dictyotene stage. Alternative splicing (AS) analysis revealed abnormal AS of deleted in azoospermia like (Dazl) and diaphanous related formin 2 (Diaph2) oogenesis-related genes in cKO mouse ovaries, and the process of AS was involved by CDC5L and PRP19.


Assuntos
Meiose , Prófase Meiótica I , Masculino , Feminino , Camundongos , Animais , Meiose/genética , Processamento Alternativo , RNA Mensageiro/metabolismo , Oócitos/metabolismo , Proteínas de Neoplasias/metabolismo
3.
FASEB J ; 37(5): e22918, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37039821

RESUMO

Sertoli cells are essential for testis development and normal spermatogenesis by providing support and nutrients. Pre-messenger RNA (pre-mRNA) processing is the basic mechanism required for gene expression, and members of the serine/arginine-rich protein (SR) family are key components of the machines that perform these basic processing events. Serine/arginine-rich splicing factor 2 (SRSF2) is an important member of the SR family; however, the physiological functions of SRSF2 in Sertoli cells are still unclear. Here, we found that SRSF2 was localized in the nuclei of Sertoli and germ cells in male mice at all stages by breeding Amh-Cre mice obtained with Srsf2-specific knockout in Sertoli cells to define the function of SRSF2 in Sertoli cells. The experimental results showed that specific deletion of SRSF2 impaired fetal Sertoli cell proliferation and induced abnormal apoptosis and severe DNA damage in seminiferous tubules, resulting in severe testicular dysplasia, seminiferous tubule atrophy, and almost no normal seminiferous tubules at postnatal day 14. Eventually, these changes resulted in failure to produce normal sperm and infertility. Further RNA-seq results showed that many key genes related to proliferation and apoptosis were downregulated; Racgap1 mRNA undergoes exon skipping. Thus, SRSF2-dependent Sertoli cells are essential for testicular development and male reproduction.


Assuntos
Sêmen , Células de Sertoli , Animais , Masculino , Camundongos , Arginina/metabolismo , RNA Mensageiro/metabolismo , Células de Sertoli/metabolismo , Espermatogênese/fisiologia , Testículo/metabolismo
4.
Cereb Cortex ; 33(6): 3193-3206, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35788651

RESUMO

BACKGROUND: The social representation theory states that individual differences in reciprocity decisions are composed of a stable central core (i.e., reciprocity propensity, RP) and a contextual-dependent periphery (i.e., sensitivity to the framing effect; SFE, the effect by how the decision is presented). However, the neural underpinnings that explain RP and SFE are still unknown. METHOD: Here, we employed prediction and lesion models to decode resting-state functional connectivity (RSFC) of RP and SFE for reciprocity decisions of healthy volunteers who underwent RS functional magnetic resonance imaging and completed one-shot trust (give frame) and distrust (take frame) games as trustees. RESULTS: Regarding the central core, reciprocity rates were positively associated between the give and take frame. Neuroimaging results showed that inter-network RSFC between the default-mode network (DMN; associated with mentalizing) and cingulo-opercular network (associated with cognitive control) contributed to the prediction of reciprocity under both frames. Regarding the periphery, behavioral results demonstrated a significant framing effect-people reciprocated more in the give than in the take frame. Our neuroimaging results revealed that intra-network RSFC of DMN (associated with mentalizing) contributed dominantly to the prediction of SFE. CONCLUSION: Our findings provide evidence for distinct neural mechanisms of RP and SFE in reciprocity decisions.


Assuntos
Conectoma , Humanos , Imageamento por Ressonância Magnética/métodos , Confiança , Neuroimagem , Vias Neurais/diagnóstico por imagem , Encéfalo/diagnóstico por imagem
5.
Cereb Cortex ; 33(15): 9280-9290, 2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37280751

RESUMO

Shape processing, whether by seeing or touching, is pivotal to object recognition and manipulation. Although the low-level signals are initially processed by different modality-specific neural circuits, multimodal responses to object shapes have been reported along both ventral and dorsal visual pathways. To understand this transitional process, we conducted visual and haptic shape perception fMRI experiments to test basic shape features (i.e. curvature and rectilinear) across the visual pathways. Using a combination of region-of-interest-based support vector machine decoding analysis and voxel selection method, we found that the top visual-discriminative voxels in the left occipital cortex (OC) could also classify haptic shape features, and the top haptic-discriminative voxels in the left posterior parietal cortex (PPC) could also classify visual shape features. Furthermore, these voxels could decode shape features in a cross-modal manner, suggesting shared neural computation across visual and haptic modalities. In the univariate analysis, the top haptic-discriminative voxels in the left PPC showed haptic rectilinear feature preference, whereas the top visual-discriminative voxels in the left OC showed no significant shape feature preference in either of the two modalities. Together, these results suggest that mid-level shape features are represented in a modality-independent manner in both the ventral and dorsal streams.


Assuntos
Reconhecimento Visual de Modelos , Percepção Visual , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual/fisiologia , Lobo Occipital/diagnóstico por imagem , Tato/fisiologia , Lobo Parietal , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico
6.
Cell Mol Life Sci ; 80(11): 343, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907803

RESUMO

Granulosa cell abnormalities are characteristics of premature ovarian insufficiency (POI). Abnormal expression of serine/arginine-rich splicing factor 1 (SRSF1) can cause various diseases, but the role of SRSF1 in mouse granulosa cells remains largely unclear. In this study, we found that SRSF1 was expressed in the nuclei of both mouse oocytes and granulosa cells. The specific knockout of Srsf1 in granulosa cells led to follicular development inhibition, decreased granulosa cell proliferation, and increased apoptosis. Gene Ontology (GO) analysis of RNA-seq results revealed abnormal expression of genes involved in DNA repair, cell killing and other signalling pathways. Alternative splicing (AS) analysis showed that SRSF1 affected DNA damage in granulosa cells by regulating genes related to DNA repair. In summary, SRSF1 in granulosa cells controls follicular development by regulating AS of genes associated with DNA repair, thereby affecting female reproduction.


Assuntos
Processamento Alternativo , Células da Granulosa , Animais , Feminino , Camundongos , Processamento Alternativo/genética , Células da Granulosa/metabolismo , Oócitos/metabolismo , RNA Mensageiro/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Transdução de Sinais/genética
7.
BMC Public Health ; 24(1): 1158, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664662

RESUMO

AIMS: This study aims to explore the relationship between waist circumference and asthma attack in adults. METHODS: In this cross-sectional study, we analysed data from 5,530 U.S. adults diagnosed with asthma. Participants were categorized into two groups based on their experience of asthma attacks: with or without asthma attacks. We employed adjusted weighted logistic regression models, weighted restricted cubic splines, subgroup and sensitivity analyses to assess the association between waist circumference and asthma attack. RESULTS: The median age of all participants was 43 years, and the median waist circumference was 98.9 cm, with a median BMI was 28.50 kg/m2. Participants in the asthma attack group had significantly higher waist circumferences than those in the non-attack group (P < 0.001). After full adjustment for body mass index-defined obesity, age, gender, race, education levels, poverty income ratio levels, smoking status, and metabolic syndrome, every 5 cm increase in waist circumference exhibited a 1.06 times higher likelihood of asthma attack probability. The weighted restricted cubic spline analysis demonstrated an increased risk of asthma attacks with rising waist circumference. Subgroup analyses confirmed this relationship across various groups differentiated by gender, age, and smoking status. When applying a stricter definition of asthma attack, the weighted logistic regression models showed robust association between waist circumference and asthma attack. CONCLUSION: Waist circumference is an independent predictor of asthma attacks. Our findings underscore the importance of waist circumference measurement in evaluating the risk of asthma attacks.


Assuntos
Asma , Circunferência da Cintura , Humanos , Masculino , Asma/epidemiologia , Feminino , Adulto , Estudos Transversais , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Fatores de Risco , Adulto Jovem , Modelos Logísticos
8.
Artigo em Inglês | MEDLINE | ID: mdl-38607218

RESUMO

Background: Acute myocardial infarction is the myocardial necrosis caused by acute and persistent ischemia and hypoxia of coronary arteries. It can be complicated with arrhythmia, shock or heart failure, and often can endanger life. The disease is most common in Europe and the United States, where about 1.5 million heart attacks occur each year. China has shown a clear upward trend in recent years, with at least 500 000 new cases and at least 2 million new cases every year. Cardiac rehabilitation nursing is a kind of comprehensive nursing that aims to restore the body function of patients with myocardial infarction. Objective: To explore the therapeutic effect of cardiac rehabilitation nursing in patients with myocardial infarction. Design: This was a case-control retrospective study. Setting: This study was conducted in the Department of Heart Center, Shanghai Sixth People's Hospital. Participants: 86 patients with acute myocardial infarction admitted to the Heart Center of Shanghai Sixth People's Hospital from January 2019 to August 2022 were selected and randomly divided into observation and control groups, with 43 cases in each group. Patients aged from 40-79 years old and were confirmed to have acute myocardial infarction by examination and histopathological analysis. Interventions: The observation group was given cardiac rehabilitation nursing, including psychological nursing, rehabilitation training, cardiac rehabilitation training, diet and defecation care and health education, and the control group was assigned routine nursing. Primary Outcome measures: (1) anxiety and depression were assessed by Zung's self-rating anxiety scale and self-rating depression scale (2) cardiac function was assessed by left ventricular ejection fraction and left ventricular end-diastolic volume (3) 6-minute walk distance (4) incidence of complications (5) length of hospital stay (6) levels of inflammatory factors and N-terminal pro-brain natriuretic peptide concentration (7) incidence of arrhythmia. Results: After the intervention, there was still no significance in either group's left ventricular end-diastolic volume level [(72.24±8.47) vs (71.98±8.35)] (P = .473). However, the anxiety and depression scores [(42.10±5.17) and (44.01±4.53) vs (44.01±4.53) and (51.37±4.85)], complication rate (6.9% vs 16.2%), length of hospital stay [(18.66±7.03) vs (26.11±8.14)], inflammatory factor levels [(1.95±0.51) and (319.47±33.72) vs (2.71±0.45) and (451.07±39.54)], serum N-terminal pro-brain natriuretic peptide level [(2525.8±1236.5) vs (3064.4±859.0)], and incidence of arrhythmia (3 cases, 2 cases, 1 case and 1 case vs 5 cases, 6 cases, 8 cases and 7 vases) in the observation group were lower compared to the control group (P = .000, P = .002, P=0.023, P = .045, P = .032, P = .011, and P = .027). The left ventricular ejection fraction level and 6-minute walk distance of the observation group [(60.39±5.38) and (347.31±21.01) vs (54.97±6.24) and (320.24±21.71)] were better relative to the control group (P = .037 and P = .000). Conclusion: For patients with myocardial infarction, the implementation of cardiac rehabilitation nursing can effectively alleviate the anxiety and depression of patients, decrease the incidence of complications as well as inflammatory factors levels, and further shorten the hospital stay of patients, with high safety. Our study provides a clinical reference for patients with myocardial infarction w who need nursing care.

9.
BMC Biol ; 21(1): 49, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36882745

RESUMO

BACKGROUND: Ovarian folliculogenesis is a tightly regulated process leading to the formation of functional oocytes and involving successive quality control mechanisms that monitor chromosomal DNA integrity and meiotic recombination. A number of factors and mechanisms have been suggested to be involved in folliculogenesis and associated with premature ovarian insufficiency, including abnormal alternative splicing (AS) of pre-mRNAs. Serine/arginine-rich splicing factor 1 (SRSF1; previously SF2/ASF) is a pivotal posttranscriptional regulator of gene expression in various biological processes. However, the physiological roles and mechanism of SRSF1 action in mouse early-stage oocytes remain elusive. Here, we show that SRSF1 is essential for primordial follicle formation and number determination during meiotic prophase I. RESULTS: The conditional knockout (cKO) of Srsf1 in mouse oocytes impairs primordial follicle formation and leads to primary ovarian insufficiency (POI). Oocyte-specific genes that regulate primordial follicle formation (e.g., Lhx8, Nobox, Sohlh1, Sohlh2, Figla, Kit, Jag1, and Rac1) are suppressed in newborn Stra8-GFPCre Srsf1Fl/Fl mouse ovaries. However, meiotic defects are the leading cause of abnormal primordial follicle formation. Immunofluorescence analyses suggest that failed synapsis and an inability to undergo recombination result in fewer homologous DNA crossovers (COs) in the Srsf1 cKO mouse ovaries. Moreover, SRSF1 directly binds and regulates the expression of the POI-related genes Six6os1 and Msh5 via AS to implement the meiotic prophase I program. CONCLUSIONS: Altogether, our data reveal the critical role of an SRSF1-mediated posttranscriptional regulatory mechanism in the mouse oocyte meiotic prophase I program, providing a framework to elucidate the molecular mechanisms of the posttranscriptional network underlying primordial follicle formation.


Assuntos
Meiose , Prófase Meiótica I , Fatores de Processamento de Serina-Arginina , Animais , Feminino , Camundongos , Processamento Alternativo , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Meiose/genética , Oócitos , Ovário , Fatores de Processamento de Serina-Arginina/genética
10.
Molecules ; 29(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38474453

RESUMO

Atractylenolide II (AT-II), the major bioactive compound of Atractylodes macrocephala, exhibits anti-cancer activity against many types of tumors, but the roles and the potential mechanisms in endometrial cancer remain unclear. In the present study, AT-II treatment was found to significantly suppress RL95-2 and AN3CA cell proliferation and glycolysis, and induced their apoptosis by inactivating the ERK signaling pathway, accompanied by the changing expression of the glycolytic key enzymes and apoptotic-related proteins. Peptidyl arginine deiminase 3 (PADI3), as the candidate target gene of AT-II, was highly expressed in the endometrial cancer tissues and associated with a poor prognosis according to bioinformatics analysis. PADI3 knockdown inhibited proliferation and glycolysis in endometrial cancer cells and induced cell apoptosis. Furthermore, AT-II negatively regulated the expression of PADI3, and PADI3 overexpression reversed the effects of AT-II on endometrial cancer cells. Our findings suggested that the anti-cancer function of AT-II is associated with the suppression of glycolysis and induction of apoptosis by blocking the PADI3-ERK signaling pathway. Thus, AT-II represents a novel therapeutic target for endometrial cancer and targeting AT-II may serve as a potential strategy for the clinical therapy of endometrial cancer.


Assuntos
Neoplasias do Endométrio , Lactonas , Sesquiterpenos , Transdução de Sinais , Feminino , Humanos , Neoplasias do Endométrio/tratamento farmacológico , Apoptose , Proliferação de Células , Proteínas Reguladoras de Apoptose/metabolismo , Glicólise , Linhagem Celular Tumoral , Proteína-Arginina Desiminase do Tipo 3/metabolismo
11.
J Am Chem Soc ; 145(35): 19347-19353, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37609696

RESUMO

Charge transfer complexes (CTCs) based on self-assembled donor and acceptor molecules allow light absorption of significantly redshifted wavelengths to either the donor or acceptor. In this work, we demonstrate a CTC embedded in a hydrogen-bonded liquid crystal elastomer (LCE), which in itself is fully reformable and reprocessable. The LCE host acts as a gate, directing the self-assembly of the CTC. When hydrogen bonding is present, the CTC behaves as a near-infrared (NIR) dye allowing photothermal actuation of the LCE. The CTC can be disassembled in specific regions of the LCE film by disrupting the hydrogen bond interactions, allowing selective NIR heating and localized actuation of the films. The metastable non-CTC state may persist for weeks or can be recovered on demand by heat treatment. Besides the CTC variability, the capability of completely reforming the shape, color, and actuation mode of the LCE provides an interactive material with unprecedented application versatility.

12.
Int J Immunogenet ; 50(4): 163-176, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37415092

RESUMO

Gynaecological tumours that threaten the health of women, especially when advanced and recurrent, have remained mostly intractable to existing treatments. Therefore, new therapeutic targets are urgently needed. Human leukocyte antigen-G (HLA-G) is a nonclassical major histocompatibility complex class I molecule typically expressed in foetuses for protection against destruction by the maternal immune system. HLA-G is also expressed under pathological conditions, such as in solid tumours, and may participate in tumour development and serve as a novel immune checkpoint in cancer. Furthermore, it is expressed in most gynaecological tumours. Therefore, inhibiting HLA-G and its receptors to block the immune escape pathway could represent a new strategy in cancer immunotherapy. To the best of our knowledge, this review is the first to summarize recent research findings on HLA-G in gynaecological oncology. We highlight the fact that HLA-G is expressed in gynaecological tumour tissues, wherein it inactivates immune effectors involved in tumour progression. Further studies on HLA-G in gynaecological oncology are needed to incorporate HLA-G into the design and evaluation of immunotherapy for malignant gynaecological diseases.


Assuntos
Neoplasias dos Genitais Femininos , Antígenos HLA-G , Feminino , Humanos , Antígenos HLA-G/genética , Neoplasias dos Genitais Femininos/genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos HLA/genética , Imunoterapia
13.
Inorg Chem ; 61(8): 3664-3673, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35171611

RESUMO

Taking advantage of the pentaethylene glycol (EO5) and deprotonation of EO5, a family of new structurally hexagonal bipyramidal Dy(III) complexes, [Dy(EO5)(2,6-dichloro-4-nitro-PhO)2](2,6-dichloro-4-nitro-PhO) (1), [Dy(EO5-BPh2)(2,6-dichloro-4-nitro-PhO)2] (2), and [Dy(EO5-BPh2)(2,6-dichloro-4-nitro-PhO)Cl] (3), were controbllably synthesized and structurally characterized. Magnetic measurements show that complex 1 is a zero-field SIM and has an observable hysteresis opening up to 4 K. Conversely, only under extra magnetic field is slow magnetic relaxation observed in 2 and 3. This considerable difference in the magnetic behavior is mainly caused by the change of the equatorial negative charge. Detailed ab initio calculations further elucidate that the quantum tunneling is induced by the presence of equatorial negative charge, and the magnetic anisotropy depends on the axial ligands. This work demonstrates that the absence of the equatorial negative charge should also be considered in the rational design of promising single molecular magnets based on the oblate ions.

14.
Biopharm Drug Dispos ; 43(1): 11-22, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34914109

RESUMO

Xanthohumol, a natural isoflavone from Humulus lupulus L., possesses biological activities. However, the biological fate of xanthohumol in vivo remains unclear. The aim of this study was to investigate the absorption and metabolism of xanthohumol in rats through UPLC-MS/MS. The plasma, urine and fecal samples were collected after oral administration of xanthohumol (25, 50, 100 mg/kg) in SD rats. The contents of xanthohumol and its metabolites were determined by UPLC-MS/MS. A total of 6 metabolites of xanthohumol were identified in rats, including methylated, glucuronidated, acid-catalyzed cyclization and oxidation, indicating xanthohumol underwent phase I and II metabolism. Besides, isoxanthohumol was the major metabolites of xanthohumol. Xanthohumol was rapidly absorbed, metabolized, and eliminated in rats. The pharmacokinetics results showed the Tmax of xanthohumol and isoxanthohumol were 3 and 2.33 h, respectively. The AUC0-t of xanthohumol and isoxanthohumol were 138.83 ± 6.03 and 38.77 ± 4.46 ng/ml·h, respectively. Furthermore, xanthohumol was mainly excreted in the form of prototype through feces and a small amount of xanthohumol was excreted through urine. These results illustrated the absorption, metabolism, and pharmacokinetics process of xanthohumol in rats, and provided a reference for the further rational applications.


Assuntos
Flavonoides , Propiofenonas , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Flavonoides/metabolismo , Flavonoides/farmacocinética , Propiofenonas/metabolismo , Propiofenonas/farmacocinética , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
15.
Biol Lett ; 17(11): 20210422, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34784800

RESUMO

In freshwater ecosystems, hatching strategy of diapausing eggs (DEs) under predation risk has important ecological implication for zooplankters. Although kairomones released by predators can induce phenotypic responses of prey, hatching patterns of DEs in response to kairomones have received contradictory conclusions in zooplankters. Maternal environment may also affect hatching strategy of DEs during predator-prey interactions. We used classical Brachionus calyciflorus-Asplanchna models to determine the timing and proportion of DE hatching in association with parental and embryonic exposure to kairomones. Results obtained from two Brachionus clones supported the hypothesis that DEs could detect Asplanchna kairomones and adjust hatching patterns. DEs showed early and synchronous hatching patterns in the environment with kairomones. Data also supported the prediction that DEs could gain information about predators from maternal environments and adjusted their hatching pattern in response to the presence of kairomones. Compared with DEs from Brachionus mothers not exposed to kairomones, DEs produced by mothers that were experienced with kairomones attained a higher hatching rate when both of them hatched in the environment either with or without kairomones. Our results suggest that DEs of B. calyciflorus possess dormant plasticity to defend against predation from Asplanchna, which may be regulated by maternal environmental effects during sexual life cycles.


Assuntos
Feromônios , Rotíferos , Animais , Ecossistema , Água Doce , Comportamento Predatório
16.
Nanotechnology ; 32(9): 095606, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33212433

RESUMO

Epitaxial horizontal nanowires (NWs) have attracted much attention due to their easily large-scale integration. From the reported literature, epitaxial growth is usually driven by minimization of strain between NW and substrate, which governs the growth along with specific crystallographic orientation. Here, we report the first homoepitaxial growth of horizontal GaN NWs from a surface-directed vapor-liquid-solid growth method. The NWs grow along with six symmetry-equivalent 〈1-100〉 (m-axis) directions, exhibiting a random 60°/120° kinked configuration. Owing to homoepitaxial growth, strain could be eliminated. From the obtained results, we suggest that the formation the horizontal NWs, and their growth direction /orientation is not directly related to the strain minimization. A general rule based on the epitaxial relationship and potential low-index growth orientation is proposed for understanding the arrangement of epitaxial horizontal NWs. It is deduced that kinking of the horizontal NWs was attributed to unintentional guided growth determined by the roughness of the substrates' surface. This study provides an insight for a better understanding of the evolution of epitaxial horizontal NWs, especially for the growth direction/orientation.

17.
Angew Chem Int Ed Engl ; 60(21): 11758-11762, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33724623

RESUMO

Extensive recent efforts have been put on the design of high-performance organic near-infrared (NIR) photothermal agents (PTAs), especially over NIR-II bio-window (1000-1350 nm). So far, the development is mainly limited by the rarity of molecules with good NIR-II response. Here, we report organic nanoparticles of intermolecular charge-transfer complexes (CTCs) with easily programmable optical absorption. By employing different common donor and acceptor molecules to form CTC nanoparticles (CT NPs), absorption peaks of CT NPs can be controllably tuned from the NIR-I to NIR-II region. Notably, CT NPs formed with perylene and TCNQ have a considerably red-shifted absorption peak at 1040 nm and achieves a good photothermal conversion efficiency of 42 % under 1064 nm excitation. These nanoparticles were used for antibacterial application with effective activity towards both Gram-negative and Gram-positive bacteria. This work opens a new avenue into the development of efficient PTAs.


Assuntos
Antibacterianos/farmacologia , Nanopartículas/química , Antibacterianos/química , Antibacterianos/efeitos da radiação , Derivados de Benzeno/química , Derivados de Benzeno/farmacologia , Derivados de Benzeno/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Raios Infravermelhos , Testes de Sensibilidade Microbiana , Nanopartículas/efeitos da radiação , Nitrilas/química , Nitrilas/farmacologia , Nitrilas/efeitos da radiação , Perileno/química , Perileno/farmacologia , Perileno/efeitos da radiação , Compostos Policíclicos/química , Compostos Policíclicos/farmacologia , Compostos Policíclicos/efeitos da radiação , Solubilidade , Staphylococcus aureus/efeitos dos fármacos , Eletricidade Estática/efeitos adversos , Compostos de Sulfidrila/química , Compostos de Sulfidrila/farmacologia , Compostos de Sulfidrila/efeitos da radiação , Água/química
18.
Small ; 16(34): e2002672, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32697430

RESUMO

Multi-modality imaging-guided cancer therapy is considered as a powerful theranostic platform enabling simultaneous precise diagnosis and treatment of cancer. However, recently reported multifunctional systems with multiple components and sophisticate structures remain major obstacles for further clinical translation. In this work, a single-photomolecular theranostic nanoplatform is fabricated via a facile nanoprecipitation strategy. By encapsulating a semiconductor oligomer (IT-S) into an amphiphilic lipid, water-dispersible IT-S nanoparticles (IT-S NPs) are prepared. The obtained IT-S NPs have a very simple construction and possess ultra-stable near-infrared (NIR) fluorescence (FL)/photoacoustic (PA) dual-modal imaging and high photothermal conversion efficiency of 72.3%. Accurate spatiotemporal distribution profiles of IT-S NPs are successfully visualized by NIR FL/PA dual-modal imaging. With the comprehensive in vivo imaging information provided by IT-S NPs, tumor photothermal ablation is readily realized under precise manipulation of laser irradiation, which greatly improves the therapeutic efficacy without any obvious side effects. Therefore, the IT-S NPs allow high tumor therapeutic efficacy under the precise guidance of FL/PA imaging techniques and thus hold great potential as an effective theranostic platform for future clinical applications.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Linhagem Celular Tumoral , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Imagem Óptica , Fototerapia , Nanomedicina Teranóstica
19.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1545-1557, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489033

RESUMO

An ultra-performance liquid chromatography(UPLC) method integrating characteristic chromatogram and eight terpenoids determination has been established for comparing the differences of Alismatis Rhizoma(Zexie) from different product areas. Thirty-seven batches of crude drugs and thirty batches of prepared slices of Alismatis Rhizoma were analyzed. The obtained data were analyzed by similarity evaluation, principal components analysis(PCA) and partial least squares discriminant analysis(PLS-DA). There were three main characteristic peaks in the characteristic chromatograms, and alisol B 23-acetate(S) was selected as the reference. Compared with the S peak, the relative retention times of the other two characteristic peaks were 0.55(alisol) and 0.77(alisol B), respectively. Peak areas and the ratio of alisol B to alisol B 23-acetate could be used to distinguish Alismatis Rhizoma from different geographical origins. The samples were divided into three groups by PCA and PLS-DA based on the content determination results, and they were "Jian Zexie"(Fujian and Jiangxi provinces), "Chuan Zexie"(Sichuan and Hubei provinces), and "Guang Zexie"(Guangxi province). The contents of chemical components in samples from different producing areas were notably different. For example, the contents of alisol A and alisol A 24-acetate were significantly higher in "Guang Zexie" compared with "Jian Zexie" and "Chuan Zexie"(P<0.000 1). The contents of alisol B and alisol C were significantly higher in "Chuan Zexie" compared with "Jian Zexie"(P<0.000 1). Combining the characteristic chromatograms and quantitative analysis of eight terpenoids, this study showed that the relative contents of components and their ratios were notable different in samples from different regions, but types and numbers of chemical compositions were basically similar. The results of this study illustrated the regional differences of Alismatis Rhizoma and their components characteristics, and provided references for authentication and quality control of Alismatis Rhizoma.


Assuntos
Rizoma , China , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Terpenos
20.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1566-1577, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489035

RESUMO

The present research was launched to improve the quality standards of Alismatis Rhizoma and supply scientific evidence and recommendations for the quality control of Alismatis Rhizoma in Chinese Pharmacopoeia(Ch. P) 2020 edition. The contents of water, total ash, heavy metals and deleterious element, pesticide residues and alcohol-soluble extract were analyzed according to the methods listed in the volume Ⅳ of Ch. P 2015 edition. Alisol B 23-acetate, alisol C 23-acetate and reference herbs were used to identify Alismatis Rhizoma by TLC method, which was developed by using a mixture of dichloromethane-methanol(15∶1) as developing solvent on silica gel GF_(254 )precoated plates. In HPLC method, alisol B 23-acetate and alisol C 23-acetate were separated with acetonitrile-water as the mobile phase and detected at 208 nm and 246 nm, respectively. Thirty-seven batches of crude drugs, thirty batches of prepared slices and nineteen batches of salt prepared slices of Alismatis Rhizoma were determined according to the methods established. The quality standards established based on the research results were specific and repeatable, and suitable for the quality evaluation of Alismatis Rhizoma. We recommended that the botanical sources, TLC examination, alcohol-soluble extract of salt prepared slices and content determination should be revised in the Ch. P 2020 edition.


Assuntos
Rizoma , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Controle de Qualidade
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