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1.
J Dairy Sci ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954568

RESUMO

It was previously thought that the Panton-Valentine leukocidin (PVL) toxin of Staphylococcus aureus (S. aureus) was not the main cause of cow mastitis. However, in recent years, detection of the gene encoding PVL has been increasing in dairy cow mastitis, which implies that PVL may be related to bovine mastitis. Therefore, we wanted to search for drugs inhibiting PVL or PVL-induced apoptosis. In this report, we investigated the apoptosis mechanism of PVL in bovine mammary epithelial cells (BMEC) and the inhibition mechanism of matrine and baicalin on PVL-induced apoptosis of BMEC. The results demonstrated that BMEC were damaged and underwent apoptosis by a standard PVL-producing strain of S. aureus (ATCC 49775), a PVL knockout mutant Δpvl 49775, complemented mutant C-Δpvl 49775, or recombinant (r)PVL in vitro. The rates of apoptosis and necrosis induced by S. aureus ATCC 49775 and C-Δpvl 49775 were significantly higher than those induced by Δpvl 49775, demonstrating that BMEC apoptosis and necrosis were associated with PVL. In addition, this research found matrine and baicalin could inhibit the apoptosis of BMEC induced by PVL-producing S. aureus and by rPVL. Matrine downregulated protein expression levels of endogenous and exogenous cleaved caspase-3, cleaved caspase-8, and cleaved caspase-9, and the effect was pronounced at a concentration of 50 µg/mL. Baicalin downregulated the expression of cleaved caspase-9. These results suggested that matrine and baicalin may have potential value against cow mastitis caused by the toxin PVL.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31958008

RESUMO

Two-dimensional (2D) materials have exotic intrinsic electronic band structures and are considered as revolutionary foundations for novel nano-devices. Band engineering of 2D materials may pave a new avenue to overcome numerous challenges in modern technologies, such as room-temperature (RT) photodetection of the light with photon energy below their bandgaps. Here, we reported the pioneered RT MoS2-based photodetection in the terahertz (THz) region via introducing Mo4+ and S2- vacancies for rational bandgap engineering. Both the generation and transport of extra carriers driven by THz electromagnetic radiations, were regulated by the vacancy concentration as well as the resistivity of MoS2 samples. Utilizing the balance between the carrier concentration fluctuation and carrier-scattering probability, a high RT photoresponsivity of 10 mA/W at 2.52 THz was realized in Mo-vacancy rich MoS2.19 sample. This work overcomes the challenge in the excessive dark current of RT THz detection and offers a convenient way for further optoelectronics and photonics devices based on bandgap engineered 2D materials.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31958010

RESUMO

A simple and green layer-by-layer assembly strategy is developed for the preparation of highly bioavailable nanocomposite photosensitizer by assembling near-infrared (NIR) light-sensitive porphyrin/G-quadruplex complexes on the surface of a highly biocompatible nanoparticle that is prepared via Zn2+-assisted coordination self-assembly of an amphiphilic amino acid. After being efficiently delivered to target site and internalized into tumor cells via enhanced permeability and retention effect and interactions between aptamers and tumor markers, as-prepared nano-assembly can be directly used as NIR light-responsive photosensitizer for tumor photodynamic therapy (PDT) since the porphyrin/G-quadruplex complexes are exposed on the nano-assembly surface and keep in active state. It can also disassemble under the synergistic stimulus of acidic pH environment and overexpressed glutathione, leasing more efficient porphyrin/G-quadruplex composite photosensitizers and meanwhile reducing the interference caused by glutathione-dependent 1O2 consumption. Since the nano-assembly can work no matter it is disassembled or not, the compulsory requirement for in vivo photosensitizer release is eliminated, thus resulting in the great improvement the bioavailability of photosensitizer. The PDT applications of the nano-assembly were well demonstrated in both in vitro cell experiments and in vivo animal experiments.

4.
Acta Pharmacol Sin ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949292

RESUMO

Metrnl is a newly identified secreted protein highly expressed in the intestinal epithelium. This study aimed to explore the role and mechanism of intestinal epithelial Metrnl in ulcerative colitis. Metrnl-/- (intestinal epithelial cell-specific Metrnl knockout) mice did not display any phenotypes of colitis under basal conditions. However, under administration of 3% dextran sodium sulfate (DSS) drinking water, colitis was more severe in Metrnl-/- mice than in WT mice, as indicated by comparisons of body weight loss, the presence of occult or gross blood per rectum, stool consistency, shrinkage in the colon, intestinal damage, and serum levels of inflammatory factors. DSS-induced colitis activated autophagy in the colon. This activation was partially inhibited by intestinal epithelial Metrnl deficiency, as indicated by a decrease in Beclin-1 and LC3-II/I and an increase in p62 in DSS-treated Metrnl-/- mice compared with WT mice. These phenomena were further confirmed by observation of autophagosomes and immunofluorescence staining for LC3 in epithelial cells. The autophagy-related AMPK-mTOR-p70S6K pathway was also activated in DSS-induced colitis, and this pathway was partially blocked by intestinal epithelial Metrnl deficiency, as indicated by a decrease in AMPK phosphorylation and an increase in mTOR and p70S6K phosphorylation in DSS-treated Metrnl-/- mice compared with WT mice. Therefore, Metrnl deficiency deteriorated ulcerative colitis at least partially through inhibition of autophagy via the AMPK-mTOR-p70S6K pathway, suggesting that Metrnl is a therapeutic target for ulcerative colitis.

5.
World J Surg ; 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31965275

RESUMO

BACKGROUND: Intra-abdominal candidiasis (IAC) is the predominant type of invasive candidiasis with high mortality in surgical intensive care patients. The purpose of this study was to investigate the impact of appropriate source control and antifungal therapy on the outcomes of critically ill surgical patients with IAC. METHODS: This was a retrospective single-center cohort study. Adult surgical patients who were admitted to the intensive care unit and diagnosed with IAC from January 1, 2003, to December 31, 2016, were enrolled. The patients' data including risk factors of IAC, infection-related information, antifungal treatment and 30-day outcomes were collected. The primary endpoint was 30-day mortality. A COX proportional hazards model was used to analyze the association between appropriate treatment and 30-day survival. RESULTS: A total of 82 patients were included in the analysis. Of these, 45 (54.9%) were complicated with septic shock at IAC diagnosis. Types of IAC included peritonitis (61.0%), intra-abdominal abscesses (23.2%) and biliary tract infections (15.9%). Of the included patients, 53 (64.6%) received appropriate source control and 44 (53.7%) appropriate antifungal therapy. Compared with patients with neither of these treatments, appropriate source control (HR 0.08, 95% CI 0.02-0.30; P < 0.001), appropriate antifungal therapy (HR 0.14, 95% CI 0.04-0.55; P = 0.005), and a combination of these treatments (HR 0.02, 95% CI 0.00-0.08; P < 0.001) were associated with reduced risk of death within 30 days after IAC diagnosis. CONCLUSION: For critically ill surgical patients with IAC, both appropriate source control and appropriate antifungal therapy were associated with reduced risk of 30-day mortality, and the protective effects of the two appropriate treatments were additive.

6.
J Phys Chem Lett ; : 952-959, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31945295

RESUMO

In this Letter, we used fluorescence microscopy to image the reversible transformation of individual CsPbCl3 nanocrystals to CsPbBr3, which enables us to quantify heterogeneity in reactivity among hundreds of nanocrystals prepared within the same batch. We observed a wide distribution of waiting times for individual nanocrystals to react as has been seen previously for cation exchange and ion intercalation. However, a significant difference for this reaction is that the switching times for changes in fluorescence intensity are dependent on the concentration of substitutional halide ions in solution (i.e., Br- or Cl-). On the basis of the high solid-state miscibility between CsPbCl3 and CsPbBr3, we develop a model in which the activation energy for anion exchange depends on the density of exchanged ions in the nanocrystal. The heterogeneity in reaction kinetics observed among individual nanocrystals limits the compositional uniformity that can be achieved in luminescent CsPbCl3-xBrx nanocrystals prepared by anion exchange.

7.
PLoS Pathog ; 16(1): e1008178, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31968013

RESUMO

Mediator of IRF3 activation (MITA, also known as stimulator of interferon genes, STING) senses the second messenger cyclic GMP-AMP (cGAMP) which is synthesized upon DNA virus infection and activates innate antiviral immune response. It has been demonstrated that the activity of MITA is delicately regulated by various post-translational modifications including polyubiquitination. In this study, we identified the deubiquitinating enzyme USP44 as a positive regulator of MITA. USP44 is recruited to MITA following DNA virus infection and removes K48-linked polyubiquitin moieties from MITA at K236, therefore prevents MITA from proteasome mediated degradation. USP44-deficiency results in acceleration of HSV-1-induced degradation of MITA and reduced induction of type I interferons (IFNs) and proinflammatory cytokines. Consistently, Usp44-/- mice are more susceptible to HSV-1 infection as indicated by higher tissue viral titers, greater tissue damage and lower survival rate. These findings suggest that USP44 plays a specific and critical role in the regulation of innate immune response against DNA viruses.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31916744

RESUMO

Injection of phase transition from layered to rock salt phase into bulk lattice and side reactions on the interfacial usually cause structure degradation, quick capacity/voltage decay and even thermal instability. Here, self-formed interfacial protective layer coupled with lattice tuning was constructed for Ni-rich cathode by simultaneous incorporation of Zr and Al in one calcination step. The migration energy between Zr and Al from surface into bulk lattice induces dual modifications from surface into bulk lattice, which effectively decrease the formation of cation mixing, the degree of anisotropic lattice change and the generation of microcracks. With the stabilization role provided by the doped Zr-Al ions and protective function endowed by the surface layer, the modified cathode material exhibits significantly enhanced capacity and voltage retention. Specifically, the capacity retention for modified cathode material reaches 99 % after 100 cycles at 1 C at 25 ℃ in the voltage of 3.0~4.3 V, which is outperformed that of 70 % for pristine cathode. The declination of the average voltage for modified cathode is only 0.025 and 0.097 V after 100 cycles at 1 C in the voltage of 3.0~4.3 V and 2.8~4.5 V, which is much lower than that of 0.230 and 0.405 V for pristine cathode. The synchronous accomplishment of modification from surface into bulk lattice for Ni-rich materials with multiple elements in one calcination step would provide some referenced value for the preparation of other cathode materials.

10.
Nucleic Acids Res ; 48(D1): D189-D197, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31906603

RESUMO

Research on RNA-associated interactions has exploded in recent years, and increasing numbers of studies are not limited to RNA-RNA and RNA-protein interactions but also include RNA-DNA/compound interactions. To facilitate the development of the interactome and promote understanding of the biological functions and molecular mechanisms of RNA, we updated RAID v2.0 to RNAInter (RNA Interactome Database), a repository for RNA-associated interactions that is freely accessible at http://www.rna-society.org/rnainter/ or http://www.rna-society.org/raid/. Compared to RAID v2.0, new features in RNAInter include (i) 8-fold more interaction data and 94 additional species; (ii) more definite annotations organized, including RNA editing/localization/modification/structure and homology interaction; (iii) advanced functions including fuzzy/batch search, interaction network and RNA dynamic expression and (iv) four embedded RNA interactome tools: RIscoper, IntaRNA, PRIdictor and DeepBind. Consequently, RNAInter contains >41 million RNA-associated interaction entries, involving more than 450 thousand unique molecules, including RNA, protein, DNA and compound. Overall, RNAInter provides a comprehensive RNA interactome resource for researchers and paves the way to investigate the regulatory landscape of cellular RNAs.

11.
Mater Sci Eng C Mater Biol Appl ; 108: 110399, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923943

RESUMO

Scaffolding plays a crucial role in bone tissue engineering by not only providing interfaces for cell adhesion, proliferation, and differentiation but also guiding neotissue formation. For this purpose, microspheres (MSs) are being increasingly used alone or in combination with other scaffolds. However, few researchers have used MSs to prepare 3D scaffolds by culture with delivered cells. In this study, we have developed covalent cross-linked gelatin MSs (ccG-MSs) (average diameter = 100-300 µm) to load mouse osteoblast MC3T3-E1 cells, which exhibit attachment and spreading on surfaces of ccG-MSs after co-culture. Significantly, the ccG-MSs can be integrated into a macroscopic construct with MC3T3-E1 cells after 5 days of cultivation. The MC3T3-E1 cells within ccG-MSs constructs show a higher viability and proliferation activity than those in the micro-cavitary gelatin gel (MCG) constructs. Calcium deposition, alkaline phosphatase activity as well as osteocalcin secretion within both ccG-MSs and MCG constructs have been evaluated in vitro and in vivo, respectively. Compared to MCG scaffolds, ccG-MS-based scaffolds can provide better cellular microenvironments for cell proliferation and osteogenic differentiation. Our findings will lay the foundation for understanding cellular behaviors in MS-based 3D constructs and help in designing MS-based bone tissue engineering scaffolds.

12.
Autoimmun Rev ; : 102461, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31917263

RESUMO

Innate immune signaling plays an important role in inflammation, and dysregulation of signaling components within this pathway has been focused as a critical mediator in initiation, progression of inflammatory autoimmune diseases. Toll-like receptors (TLRs) are the most upstream pattern recognition receptors in the immune cells, detecting pathogen associated molecular patterns, initiating signal transduction, by which interleukin-1 receptor-associated kinase (IRAK) family mediates activating signal from TLRs and interleukin-1 receptor. The family comprises of four members, IRAK1, IRAK2, IRAK-M, IRAK4. The family members have a role in either positive or negative regulation of innate immunity, adaptive immunity and inflammation. Accumulated evidence proves that IRAK performs significantly in the pathogenesis of inflammatory autoimmune disorders. On the one hand, both patients and animal modes reported abnormal expression of the family members. On the other hand, functional study in vivo and in vitro demonstrated that the members are implicated in the development of the diseases. Interestingly, IRAK inhibition has potential therapeutic benefits. In this review, we focus on the family, review the physiological roles in different immune cells, and summarize emerging data for highlighting the importance of them in inflammatory autoimmunity.

13.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(1): 41-43, 2020 Jan 10.
Artigo em Chinês | MEDLINE | ID: mdl-31922594

RESUMO

OBJECTIVE: To explore the genetic basis of a patient featuring global developmental delay, intellectual disability, cleft palate, seizures and hypotonia. METHODS: Clinical examination and laboratory tests were carried out. Peripheral blood samples were obtained from the patient and his parents. Whole genomic DNA was extracted and subjected to next generation sequencing. Candidate variation was analyzed by using bioinformatic software and validated by Sanger sequencing. RESULTS: The proband was found to carry a heterozygous c.2117T>C (p.Leu706Pro) variant of the NEDD4L gene, which was a de novo variant validated by Sanger sequencing and predicted to be likely pathogenic according to the American College of Medical Genetics Guidelines. CONCLUSION: The heterozygous variant of c.2117T>C (p.Leu706Pro) of the NEDD4L gene probably underlies the disorders in the patient.


Assuntos
Ubiquitina-Proteína Ligases Nedd4 , Heterotopia Nodular Periventricular , Testes Genéticos , Heterozigoto , Humanos , Deficiência Intelectual/etiologia , Deficiência Intelectual/genética , Masculino , Mutação , Ubiquitina-Proteína Ligases Nedd4/genética , Heterotopia Nodular Periventricular/complicações , Heterotopia Nodular Periventricular/genética
14.
J Coll Physicians Surg Pak ; 30(1): 13-17, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31931925

RESUMO

OBJECTIVE: To evaluate the recovery influence of CO2 pneumoperitoneum pressure for transabdominal preperitoneal hernioplasty (TAPP). STUDY DESIGN: Experimental study. PLACE AND DURATION OF STUDY: General Department II, Zhongda Hospital, Southeast University, Nanjing, China, from August 2016 to October 2018. METHODOLOGY: Eighty cases were enrolled prospectively and divided into three groups in chronological order. A 14 mmHg CO2 pressure was used for negative control group while the pressure was controlled at 12 mmHg for observation group and 10 mmHg for intervention group. General information included the patients' age, gender, type of hernia, hernia defect size, dissection of inguinal area, type of patch, time of operation, and frequency of swelling of perineum. Postoperative recovery was compared among the three groups at 24 hours and 1 month after surgery, including pain scores, foreign body sensation, local complications, urinary retention, swelling of the perineum, sex life and mobility. RESULTS: Seventy-eight patients were included in the final analysis. There were no differences among the three groups in patients' age, gender, type of hernia, hernia defect size, dissection of inguinal area and type of patch. However, the time of operation of intervention group increased (p=0.015) and incidence of swelling of perineum decreased than other two groups (p<0.05). After 24 hours, there were no significant differences in pain, foreign body sensation, local complications and urinary retention. Perineal swelling remission rate of intervention group was better than other two groups (p<0.05). After one month, three groups had no differences in the all terms of pain, foreign body sensation, sexual life and perineal swelling residual rate. CONCLUSION: Low pneumoperitoneum pressure can relieve swelling of perineum perioperatively and improve recovery of TAPP.

15.
Medicine (Baltimore) ; 99(1): e18503, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31895784

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease. In clinical practice, we have observed that some HLH patients who have features of systemic autoinflammatory diseases (SAIDs) exhibit unique clinical manifestations and outcomes different from other HLH patients.We analyzed data from 25 HLH patients who were considered to have SAIDs; data were collected from patients of our center between January 1, 2015 and September 1, 2018.The median age of the patients was 1.75 years. In the early phase, all patients had a fever and 92% of patients had a rash; 96% of patients had high white blood cell count (WBC), C-reaction protein, and erythrocyte sedimentation rate. With progression, the above laboratory results decreased gradually. During the HLH period, we compared SAIDs-related HLH and Epstein-Barr virus (EBV)-related HLH and found that rash was more common (92%, P < .001) and splenomegaly was less common (64%, P = .023) in SAIDs-related HLH. Further, WBC, ferritin, and Interleukin-6 levels in SAIDs-related HLH patients were higher than those in EBV-related HLH patients. In contrast, hemoglobin, triglyceride, sCD25, Interleukin-10, and interferon-γ levels in SAIDs-related HLH patients were lower compared with those in EBV-related HLH patients. SAIDs-related HLH patients received a modified HLH-2004 protocol at our center. Most patients had a good prognosis.We provide a summary of the unique clinical and laboratory features, treatment protocols, and outcomes of SAIDs patients with HLH at onset. The findings indicate that these patients had a better response to corticosteroids and cyclosporin compared with EBV-related HLH patients.


Assuntos
Doenças Autoimunes/patologia , Infecções por Vírus Epstein-Barr/patologia , Exantema/etiologia , Herpesvirus Humano 4 , Linfo-Histiocitose Hemofagocítica/patologia , Corticosteroides/uso terapêutico , Doenças Autoimunes/imunologia , Doenças Autoimunes/virologia , Sedimentação Sanguínea , Proteína C-Reativa , Ciclosporina/uso terapêutico , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Exantema/patologia , Exantema/virologia , Feminino , Humanos , Lactente , Contagem de Leucócitos , Linfo-Histiocitose Hemofagocítica/imunologia , Linfo-Histiocitose Hemofagocítica/virologia , Masculino , Esplenomegalia/imunologia , Esplenomegalia/virologia , Resultado do Tratamento
16.
BMJ ; 368: l6669, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915124

RESUMO

OBJECTIVE: To examine how a healthy lifestyle is related to life expectancy that is free from major chronic diseases. DESIGN: Prospective cohort study. SETTING AND PARTICIPANTS: The Nurses' Health Study (1980-2014; n=73 196) and the Health Professionals Follow-Up Study (1986-2014; n=38 366). MAIN EXPOSURES: Five low risk lifestyle factors: never smoking, body mass index 18.5-24.9, moderate to vigorous physical activity (≥30 minutes/day), moderate alcohol intake (women: 5-15 g/day; men 5-30 g/day), and a higher diet quality score (upper 40%). MAIN OUTCOME: Life expectancy free of diabetes, cardiovascular diseases, and cancer. RESULTS: The life expectancy free of diabetes, cardiovascular diseases, and cancer at age 50 was 23.7 years (95% confidence interval 22.6 to 24.7) for women who adopted no low risk lifestyle factors, in contrast to 34.4 years (33.1 to 35.5) for women who adopted four or five low risk factors. At age 50, the life expectancy free of any of these chronic diseases was 23.5 (22.3 to 24.7) years among men who adopted no low risk lifestyle factors and 31.1 (29.5 to 32.5) years in men who adopted four or five low risk lifestyle factors. For current male smokers who smoked heavily (≥15 cigarettes/day) or obese men and women (body mass index ≥30), their disease-free life expectancies accounted for the lowest proportion (≤75%) of total life expectancy at age 50. CONCLUSION: Adherence to a healthy lifestyle at mid-life is associated with a longer life expectancy free of major chronic diseases.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Estilo de Vida Saudável/fisiologia , Expectativa de Vida , Neoplasias , Comportamento de Redução do Risco , Adulto , Consumo de Bebidas Alcoólicas , Índice de Massa Corporal , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/psicologia , Diabetes Mellitus Tipo 2/prevenção & controle , Diabetes Mellitus Tipo 2/psicologia , Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/prevenção & controle , Neoplasias/psicologia , Pesquisa em Enfermagem , Estudos Prospectivos , Fumar
17.
Int J Equity Health ; 19(1): 6, 2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906960

RESUMO

BACKGROUND: Aging and the chronic non-communicable diseases (NCDs) challenge the Chinese government in the process of providing hospitalization services fairly and reasonably. The Chinese government has developed the basic medical insurance system to solve the problem of "expensive medical cost and difficult medical services" for vulnerable groups and alleviate the unfair phenomenon. However, few studies have confirmed its effect through longitudinal comparison. This study aimed to explore the trend in the inequity of inpatient use among middle-aged and elderly individuals with NCDs in China. METHODS: This longitudinal comparative study was based on CHARLS data in 2011, 2013 and 2015. Concentration index (CI) was used to measure the variation trend of inequity of inpatient services utilization, while the decomposition method of the CI was applied to measure the factors contributing to inequity in inpatient services utilization. The effect of each factor on the change of inequity in inpatient services utilization was divided into the change of the elasticity and the change of inequality using the Oaxaca-type decomposition method. RESULTS: The affluent middle-aged and elderly patients with NCDs used more inpatient services than poor groups. The per capita household consumption expenditure (PCE) and Urban Employee Basic Medical Insurance (UEBMI) contributed to the decline in pro-rich inequality of inpatient use, while the New Rural Cooperative Medical Scheme (NRCMS) contributed to the decline in pro-poor inequality of inpatient use. CONCLUSIONS: There was a certain degree of pro-rich unfairness in the probability and frequency of inpatient services utilization for middle-aged and elderly individuals with NCDs in China. The decrease of pro-wealth contribution of PCE and UEBMI offset the decrease of pro-poor contribution of NRCMS, and improved the equity of inpatient services utilization, favoring poor people.

18.
Nano Lett ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31940203

RESUMO

The in situ construction of nano-assembly has been demonstrated to improve the performance of bioactive molecules, but the control of the morphology of nanomaterials in vivo still remains a tremendous challenge. Herein, a photothermal-promoted morphology transformation (PMT) strategy is developed to accelerate the formation of nanomaterials for improving biological performance of drug molecules. Compared with the spontaneous process, the rate of transformation increases by ~4 times in PMT process. Owing to the raise of the assembly rate, the tumor accumulation of drugs is ~2-fold than that without photo irradiation, which inhibits the tumor growth effectively. More importantly, the chemical re-assembly process in vitro and in vivo is monitored by the advanced ratiometric photoacoustic image, confirming the photo-induced transformation acceleration. Through the noninvasively artificial control on assembly dynamics in vivo, the PMT strategy provides a new insight for developing the intelligent theranostics.

19.
Cell Rep ; 30(2): 432-441.e3, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31940487

RESUMO

The hippocampus and retrosplenial cortex (RSC) play indispensable roles in memory formation, and importantly, a hippocampal oscillation known as ripple is key to consolidation of new memories. However, it remains unclear how the hippocampus and RSC communicate and the role of ripple oscillation in coordinating the activity between these two brain regions. Here, we record from the dorsal hippocampus and RSC simultaneously in freely behaving mice during sleep and reveal that the RSC displays a pre-ripple activation associated with slow and fast oscillations. Immediately after ripples, a subpopulation of RSC putative inhibitory neurons increases firing activity, while most RSC putative excitatory neurons decrease activity. Consistently, optogenetic stimulation of this hippocampus-RSC pathway activates and suppresses RSC putative inhibitory and excitatory neurons, respectively. These results suggest that the dorsal hippocampus mainly inhibits RSC activity via its direct innervation of RSC inhibitory neurons, which overshadows the RSC in supporting learning and memory functions.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31943644

RESUMO

The sensitivity of conventional thin film OFETs-based sensors is limited by the diffusion of analytes through bulk films, and remains the central challenge in sensing technology. Here, for the first time we reported an ultrasensitive (sub-ppb level) sensor exploiting n-type monolayer molecular crystals (MMCs) with porous two-dimensional structures. Thanks to monolayer crystal structure of NDI3HU-DTYM2 (NDI) and controlled formation of porous structure, a world-record detection limit of NH 3 (0.1 ppb) was achieved. Moreover, the MMC-OFETs also enabled direct detection of solid analytes of biological amine derivatives, such as dopamine at an extremely low concentration of 500 ppb. The remarkably improved sensing performances of MMC-OFETs open up the possibility of engineering OFETs for ultrasensitive (bio)chemical sensing.

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