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1.
Abdom Radiol (NY) ; 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33630127

RESUMO

OBJECTIVE: To evaluate the clinical efficacy and long-term outcomes associated with the treatment of hepatic vein (HV)-type Budd-Chiari syndrome (BCS) via accessory HV (AHV) recanalization. METHODS: In total, 26 HV-type BCS patients underwent AHV recanalization between July 2014 and December 2019 at our hospital, while 73 HV-type BCS patients without compensatory AHV underwent main HV (MHV) recanalization and served as controls in the present study. Short- and long-term clinical outcomes were compared. RESULTS: AHV and MHV recanalization approaches were both associated with 100% technical success rates, with one recanalization procedure being performed per patient. Respective clinical success rates for the AHV and MHV recanalization approaches were 96.2% and 94.5% (P = 0.744). Re-obstruction rates were comparable between these two approaches at 20% and 34.8%, respectively (P = 0.17). Primary cumulative 1-, 2-, and 5-year patency rates in the AHV group were 96.0%, 91.6%, and 76.3%, respectively, whereas in the MHV group, these three respective rates were 87.0%, 78.6%, and 58.6% (P = 0.048). Secondary cumulative 1-, 2-, and 5-year patency rates in the AHV group were 96.0%, 96.0%, and 96.0%, respectively, whereas in the MHV group, they were 97.1%, 97.1%, and 81.8%, respectively (P = 0.289). Cumulative 1-, 2-, and 5-year survival rates for AHV group patients were 96.0%, 96.0%, and 96.0%, respectively, while for the MHV group, these respective rates were 98.6%, 95.2%, and 89.7% (P = 0.462). CONCLUSION: HV-type BCS can be safely and effectively treated via AHV recanalization, which may achieve longer patency relative to MHV recanalization.

2.
Proc Natl Acad Sci U S A ; 118(9)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33619099

RESUMO

Natural aerosols in pristine regions form the baseline used to evaluate the impact of anthropogenic aerosols on climate. Sea spray aerosol (SSA) is a major component of natural aerosols. Despite its importance, the abundance of SSA is poorly constrained. It is generally accepted that wind-driven wave breaking is the principle governing SSA production. This mechanism alone, however, is insufficient to explain the variability of SSA concentration at given wind speed. The role of other parameters, such as sea surface temperature (SST), remains controversial. Here, we show that higher SST promotes SSA mass generation at a wide range of wind speed levels over the remote Pacific and Atlantic Oceans, in addition to demonstrating the wind-driven SSA production mechanism. The results are from a global scale dataset of airborne SSA measurements at 150 to 200 m above the ocean surface during the NASA Atmospheric Tomography Mission. Statistical analysis suggests that accounting for SST greatly enhances the predictability of the observed SSA concentration compared to using wind speed alone. Our results support implementing SST into SSA source functions in global models to better understand the atmospheric burdens of SSA.

3.
Ecology ; : e03302, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33560518

RESUMO

Vespicochory, defined as seed dispersal by wasps, was first reported by Pellmyr (1985). To date, vespicochory has only been documented in nine plant species belonging to five plant families, themselves dispersed by five wasp genera (Burge and Beck 2019; Chen et al. 2020). All known wasp-dispersed plants bear seeds with lipid-rich elaiosomes that are also thought to attract ants to disperse their seeds (myrmecochory) (Lengyel et al. 2010). A recent study revealed that Stemona tuberosa produces hydrocarbons that smell like prey to attract dispersing wasps (Chen et al. 2018). The data to date suggests that vespicochory evolved from myrmecochory and change in chemical cues are likely for the evolution of vespicochory. Wasps often transport diaspores (seed and elaiosome) from foraging plants to their nests, and consume lipid-rich elaiosomes but not seeds, representing an effective seed dispersal service, significantly longer distance dispersal, compared to dispersal by ants (Chen et al. 2017; Fig. 1). Since over 11,000 plant species produce diaspores with lipid-rich elaiosomes dispersed by ants (Lengyel et al. 2010), the potential for vespicochory might be significantly underestimated (Chen et al. 2020). Relying on wasps could be a strategy to increase seed dispersal occurrence and distance in myrmecochorous plants.

4.
Transl Stroke Res ; 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33539006

RESUMO

Polarization of microglia/macrophages toward the pro-inflammatory phenotype is an important contributor to neuroinflammation after intracerebral hemorrhage (ICH). Dectin-1 is a pattern recognition receptor that has been reported to play a key role in regulating neuroinflammation in ischemic stroke and spinal cord injury. However, the role and mechanism of action of Dectin-1 after ICH remains unclear. In this study, we investigated the effect of Dectin-1 on modulating the microglia/macrophage phenotype and neuroinflammation and the possible underlying mechanism after ICH. We found that Dectin-1 expression increased after ICH, and was mainly localized in microglia/macrophages. Neutrophil infiltration and microglia/macrophage polarization toward the pro-inflammatory phenotype increased after ICH. However, treatment with a Dectin-1 inhibitor reversed these phenomena and induced a shift the anti-inflammatory phenotype in microglia/macrophages; this resulted in alleviation of neurological dysfunction and facilitated hematoma clearance after ICH. We also found that Dectin-1 crosstalks with the downstream pro-inflammatory pathway, Card9/NF-κB, by activating spleen tyrosine kinase (Syk) both in vivo and in vitro. In conclusion, our data suggest that Dectin-1 is involved in the microglia/macrophage polarization and functional recovery after ICH, and that this mechanism, at least in part, may contribute to the involvement of the Syk/Card9/NF-kB pathway.

5.
Microbiol Resour Announc ; 9(50)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33303670

RESUMO

"Candidatus Dehalogenimonas etheniformans" strain GP couples growth with the reductive dechlorination of vinyl chloride and several polychlorinated ethenes. The genome sequence comprises a circular 2.07-Mb chromosome with a G+C content of 51.9% and harbors 50 putative reductive dehalogenase genes.

6.
Environ Sci Technol ; 54(23): 14994-15003, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33190477

RESUMO

Fluorinated organic compounds have emerged as environmental constituents of concern. We demonstrate that the alkane degrader Pseudomonas sp. strain 273 utilizes terminally monofluorinated C7-C10 alkanes and 1,10-difluorodecane (DFD) as the sole carbon and energy sources in the presence of oxygen. Strain 273 degraded 1-fluorodecane (FD) (5.97 ± 0.22 mM, nominal) and DFD (5.62 ± 0.13 mM, nominal) within 7 days of incubation, and 92.7 ± 3.8 and 90.1 ± 1.9% of the theoretical maximum amounts of fluorine were recovered as inorganic fluoride, respectively. With n-decane, strain 273 attained (3.24 ± 0.14) × 107 cells per µmol of carbon consumed, while lower biomass yields of (2.48 ± 0.15) × 107 and (1.62 ± 0.23) × 107 cells were measured with FD or DFD as electron donors, respectively. The organism coupled decanol and decanoate oxidation to denitrification, but the utilization of (fluoro)alkanes was strictly oxygen-dependent, presumably because the initial attack on the terminal carbon requires oxygen. Fluorohexanoate was detected as an intermediate in cultures grown with FD or DFD, suggesting that the initial attack on the fluoroalkanes can occur on the terminal methyl or fluoromethyl groups. The findings indicate that specialized bacteria such as Pseudomonas sp. strain 273 can break carbon-fluorine bonds most likely with oxygenolytic enzyme systems and that terminally monofluorinated alkanes are susceptible to microbial degradation. The findings have implications for the fate of components associated with aqueous film-forming foam (AFFF) mixtures.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33214104

RESUMO

In this study Vis/NIR spectroscopy was applied to evaluate soluble solids content (SSC) of tomato. A total of 168 tomato samples with five different maturity stages, were measured by two developed systems with the wavelength ranges of 500-930 nm and 900-1400 nm, respectively. The raw spectral data were pre-processed by first derivative and standard normal variate (SNV), respectively, and then the effective wavelengths were selected using competitive adaptive reweighted sampling (CARS) and random frog (RF). Partial least squares (PLS) and least square-support vector machines (LS-SVM) were employed to build the prediction models to evaluate SSC in tomatoes. The prediction results revealed that the best performance was obtained using the PLS model with the optimal wavelengths selected by CARS in the range of 900-1400 nm (Rp = 0.820 and RMSEP = 0.207 °Brix). Meanwhile, this best model yielded desirable results with Rp and RMSEP of 0.830 and 0.316 °Brix, respectively, in 60 samples of the independent set. The method proposed from this study can provide an effective and quick way to predict SSC in tomato.

8.
World Neurosurg ; 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33217589

RESUMO

OBJECTIVE: The best management of asymptomatic moyamoya disease (MMD) remains controversial. In this study, the authors aimed to explore an experience for treatment modality for asymptomatic MMD. METHODS: The authors retrospectively reviewed a total of 23 patients (age range 30-58 years) with asymptomatic MMD during the past 5 years at their institutions. The patients were divided into 2 groups: The surgical group included 11 patients, and the conservative group included 12 patients. The demographic, radiologic, and clinical findings of the patients were evaluated. At follow-up over 13-65 months, the future clinical and radiologic progression events were evaluated. RESULTS: During the follow-up period, 3 patients suffered from future clinical progression events in the conservative group: 1 experienced stroke, and 2 experienced transient ischemic attack. Among the patients in the surgical group, only 1 experienced transient ischemic attack. Kaplan-Meier analysis showed that patients undergoing surgeries had longer clinical progression-free survival times compared with patients in the conservative group (P = 0.002). CONCLUSIONS: Surgical treatment may be an alternative choice for patients with asymptomatic MMD. However, the best strategy for asymptomatic MMD in order to reduce future cerebrovascular risks still needs to be further explored.

9.
Stem Cells Int ; 2020: 2853650, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204276

RESUMO

Background: Spinal cord injury (SCI) is one of the serious neurological diseases that occur in young people with high morbidity and disability. However, there is still a lack of effective treatments for it. Stem cell (SC) treatment of SCI has gradually become a new research hotspot over the past decades. This article is aimed at reviewing the research progress of SC therapy for SCI. Methods: Review the literature and summarize the effects, strategies, related mechanisms, safety, and clinical application of different SC types and new approaches in combination with SC in SCI treatment. Results: A large number of studies have focused on SC therapy for SCI, most of which showed good effects. The common SC types for SCI treatment include mesenchymal stem cells (MSCs), hematopoietic stem cells (HSCs), neural stem cells (NSCs), induced pluripotent stem cells (iPSCs), and embryonic stem cells (ESCs). The modes of treatment include in vivo and in vitro induction. The pathways of transplantation consist of intravenous, transarterial, nasal, intraperitoneal, intrathecal, and intramedullary injections. Most of the SC treatments for SCI use a number of cells ranging from tens of thousands to millions. Early or late SC administration, application of immunosuppressant or not are still controversies. Potential mechanisms of SC therapy include tissue repair and replacement, neurotrophy, and regeneration and promotion of angiogenesis, antiapoptosis, and anti-inflammatory. Common safety issues include thrombosis and embolism, tumorigenicity and instability, infection, high fever, and even death. Recently, some new approaches, such as the pharmacological activation of endogenous SCs, biomaterials, 3D print, and optogenetics, have been also developed, which greatly improved the application of SC therapy for SCI. Conclusion: Most studies support the effects of SC therapy on SCI, while a few studies do not. The cell types, mechanisms, and strategies of SC therapy for SCI are very different among studies. In addition, the safety cannot be ignored, and more clinical trials are required. The application of new technology will promote SC therapy of SCI.

10.
J Fluoresc ; 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33145674

RESUMO

A coumarin-based probe, FP2, was designed for the differential detection of fluoride anions and thiols, i.e., the corresponding nucleophilic substitution products from fluorine-containing G agents and sulfur-containing V agents, thus having the potential to discriminate between these two nerve agents. FP2 with two functional reaction groups, α, ß-unsaturated ketone and silyl groups, can react selectively with fluoride anions and thiols at the µM level respectively. Intriguingly, in the THF solution, FP2 reacts with the fluoride anion but not with the thiol, whereas in the EtOH/HEPES solution, FP2 reacts with the thiol but not with the fluoride anion. As a result, FP2 can produce different fluorophores in the two detection solutions, thus displaying significant fluorescence changes. In addition, the FP2 detection system can show a significant color change from colorless to yellow within seconds when detecting fluoride anions in THF detection solutions, and from yellow to light blue when detecting thiols in EtOH/HEPES solutions, which will facilitate visual detection by emergency responders at the scene of an incident involving a nerve agent.

11.
Sci Rep ; 10(1): 17486, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060633

RESUMO

Numb is a negative regulator of Notch signal pathway. Previous study has demonstrated that Notch signal pathway activation is required for hepatic progenitor cell (HPC) differentiating into cholangiocytes in cholestatic liver fibrosis (CLF), and Huang Qi Decoction (HQD) could prevent CLF through inhibition of the Notch signal pathway. However, the role of Numb in HQD against CLF is yet unclear. Thus, CLF rats transplanted into rat bone marrow-derived mesenchymal stem cells with knocked down Numb gene (BMSCNumb-KD) were treated with HQD. Simultaneously, Numb gene knockdown was also performed in WB-F344 cell line and then treated with refined HQD in vitro. In vivo study revealed that liver fibrosis was inhibited by HQD plus BMSCNumb-KD treatment, while Hyp content in liver tissue, the gene and protein expression of α-SMA, gene expression of Col I, TNF-α, and TGF-ß1 were increased compared to that in HQD group. Furthermore, Notch signal pathway was inhibited by HQD plus BMSCNumb-KD, while the protein expression of Numb was decreased and RBP-Jκ and Hes1 was increased compared to that in HQD group. In vitro, HQD reduced the differentiation of WB-F344 cells into cholangiocyte phenotype, while this effect was attenuated after Numb-knockdown. This study highlights that the absence of hepatic stem cell Numb gene decreases effect of HQD against CLF, which give rise the conclusion that Numb might be a potential target for HQD against CLF.

12.
J Cell Physiol ; 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32964440

RESUMO

Glioblastoma (GBM) is the most common, malignant, and deadly primary glioma. Six-transmembrane epithelial antigen of prostate (STEAP) family is involved in tumorigenesis; here, we have explored the biological function and the prognostic value of the STEAP family in GBM. Differentially expressed STEAP genes in tumor and normal samples were screened by using The Cancer Genome Atlas (TCGA) database. Univariate and multivariate Cox regression identified the prognosis-related genes: STEAP2 and STEAP3, which were involved in the regulation of immune response and cell cycle. Finally, a prognostic nomogram combining age, gender, chemotherapy, radiotherapy, IDH1 status, and the risk score model based on STEAP2 and STEAP3 was built and further validated in TCGA and Chinese Glioma Genome Atlas (CGGA) cohorts via concordance index and calibration plot, which suggested a favorable value for prognosis prediction. In conclusion, our results provided a comprehensive analysis of the STEAP family and a model for the prognosis prediction of GBM.

13.
Front Oncol ; 10: 1412, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32974148

RESUMO

Objective: Meningiomas presented preferred intracranial distribution, which may reflect potential biological natures. This study aimed to analyze the preferred locations of meningioma according to different biological characteristics. Method: A total of 1,107 patients pathologically diagnosed with meningiomas between January 2012 and December 2016 were retrospectively analyzed. Preoperative MRI were normalized, and lesions were semiautomatically segmented. The stereospecific frequency and p value heatmaps were constructed to compare two biological phenotypes using two-tailed Fisher's exact test. Age, sex, WHO grades, extent of resection (EOR), recurrence, and immunohistochemical markers including p53, Ki67, epithelial membrane antigen (EMA), progesterone receptor (PR), and CD34 were statistically analyzed. Recurrence-free survival (RFS) were analyzed by Kaplan-Meier method. Result: Of 1,107 cases, convexity (20.8%), parasagittal (16.1%), and falx (11.4%) were the most predominant loci of meningiomas. The p-value heatmap suggested lesion predominance in the left frontal and occipital convexity among older patients while in the left sphenoid wing, and right falx, parasellar/cavernous sinus, and middle fossa among younger patients. Lesions located at anterior fossa and frontal structures were more frequently seen in the male while left parietal falx and tentorial regions, and right cerebellopontine angle in the female. Grades II and III lesions presented predominance in the frontal structures compared with grade I ones. Meningiomas at the left parasagittal sinus and falx, tentorium, intraventricular regions, and skull-base structures were significantly to receive subtotal resection. Lesions with p53 positivity were statistically located at the left frontal regions and parasellar/cavernous sinus, higher Ki67 index at the left frontal and bilateral parietal convexity and right parasellar/cavernous sinus, EMA negativity at the right olfactory groove and left middle fossa, and CD34 positivity at the sellar regions and right sphenoid wing. Tumor recurrence rates for grades I, II, and III were 2.8, 7.9, and 53.8%, respectively. Inferior RFS, higher Ki67 index, grades II and III, and a larger preoperative volume were observed in older patients. Recurrent meningiomas were more frequently found at the occipital convexity, tentorium, sellar regions, parasagittal sinus, and left sphenoid wing. Conclusion: The preferred locations of meningioma could be observed according to different biological characteristics, which might be helpful for clinical decisions.

14.
Transl Stroke Res ; 2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32918259

RESUMO

Intracerebral hemorrhage (ICH) is a cerebrovascular disease with high mortality and morbidity for which effective treatments are currently lacking. Wogonin is a major flavonoid compound isolated from Scutellaria radix. Accumulating evidence suggests that wogonin plays a crucial role in anti-inflammatory and anti-oxidative stress. Treatment of microglia with nuclear receptor agonists augments the expression of phagocytosis-related genes. However, the neuroprotective effects of wogonin in ICH remain obscure. In this study, we elucidated an innovative mechanism by which wogonin acts to enhance phagocytosis in a murine model of ICH. Wogonin promoted hematoma clearance and improved neurological recovery after ICH by upregulating the expression of Axl, MerTK, CD36, and LAMP2 in perihematomal microglia and BV2 cells. Treatment of a murine model of ICH with wogonin stimulated microglial phagocytosis in vitro. Further, we demonstrated that wogonin dramatically attenuated inflammatory and oxidative stress responses in a murine model of ICH by reducing the expression of pro-inflammatory cytokines and pro-oxidant enzymes such as TNF-α, IL-1ß, and inducible nitric oxide synthase (iNOS) after ICH. The effects of wogonin were abolished by administration of the PPAR-γ inhibitor GW9662. In conclusion, our data suggest that wogonin facilitates hematoma clearance and neurobehavioral recovery by targeting PPAR-γ.

15.
BMC Genet ; 21(1): 102, 2020 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-32919456

RESUMO

BACKGROUND: Amorphophallus albus P. Y. Liu & J. F. Chen (Araceae) is a plant species with extremely small populations (PSESP) and an important economic crop endemic to dry-hot valleys along the Jinsha River. In order to gain information for sustaining the development and conservation of A. albus, we studied the genetic diversity and population structure of this species using microsatellite markers (SSR). In this study, we analysed 364 individuals belonging to 24 populations, including four wild populations and three ex-situ cultivated populations, collected in the provinces Yunnan, Sichuan and Hubei. RESULTS: The population genetic analyses indicated that A. albus possesses moderate genetic diversity with the percentage of polymorphic loci (PPL) from 69.23 to 100%, an expected heterozygosity (He) of 0.504 and an average Shannon's Information Index (I) 0.912. Analysis of molecular variance (AMOVA) indicated that most of the variance (71%) resided within populations and the estimated gene flow (Nm) was 0.61. The results of UPGMA cluster tree, STRUCTURE analyses together with the Mantel test (R2 = 0.352, P < 0.01) indicated that geographically closely located populations are clustered together with some exceptions. CONCLUSIONS: Our results showed that A. albus still possesses moderate genetic variation in most of the studied populations, and for now, most cultivated populations were naturally distributed but still some reintroduction exists. For sustaining the present genetic variation, some protections measures are necessary for the wild populations and also for the cultivated ones with high genetic diversity.

16.
Cell Transplant ; 29: 963689720950226, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841050

RESUMO

Apoptosis is a vital pathological factor that accounts for the poor prognosis of traumatic spinal cord injury (t-SCI). The 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3) is a critical regulator for energy metabolism and proven to have antiapoptotic effects. This study aimed to investigate the neuroprotective role of PFKFB3 in t-SCI. A compressive clip was introduced to establish the t-SCI model. Herein, we identified that PFKFB3 was extensively distributed in neurons, and PFKFB3 levels significantly increased and peaked 24 h after t-SCI. Additionally, knockdown of PFKFB3 inhibited glycolysis, accompanied by aggravated neuronal apoptosis and white matter injury, while pharmacological activation of PFKFB3 with meclizine significantly enhanced glycolysis, attenuated t-SCI-induced spinal cord injury, and alleviated neurological impairment. The PFKFB3 agonist, meclizine, activated cyclin-dependent kinase 1 (CDK1) and promoted the phosphorylation of p27, ultimately suppressing neuronal apoptosis. However, the neuroprotective effects of meclizine against t-SCI were abolished by the CDK1 antagonist, RO3306. In summary, our data demonstrated that PFKFB3 contributes robust neuroprotection against t-SCI by enhancing glycolysis and modulating CDK1-related antiapoptotic signals. Moreover, targeting PFKFB3 may be a novel and promising therapeutic strategy for t-SCI.

17.
Environ Microbiol ; 22(9): 4057-4066, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32783260

RESUMO

The aromatic hydrocarbon naphthalene, which occurs in coal and oil, can be degraded by aerobic or anaerobic microorganisms. A wide-spread electron acceptor for the latter is sulfate. Evidence for in situ naphthalene degradation stems in particular from the detection of 2-naphthoate and [5,6,7,8]-tetrahydro-2-naphthoate in oil field samples. Because such intermediates are usually not detected in laboratory cultures with high sulfate concentrations, one may suppose that conditions in reservoirs, such as sulfate limitation, trigger metabolite release. Indeed, if naphthalene-grown cells of marine sulfate-reducing Deltaproteobacteria (strains NaphS2, NaphS3 and NaphS6) were transferred to sulfate-free medium, they released 2-naphthoate and [5,6,7,8]-tetrahydro-2-naphthoate while still consuming naphthalene. With 2-naphthoate as initial substrate, cells produced [5,6,7,8]-tetrahydro-2-naphthoate and the hydrocarbon, naphthalene, indicating reversibility of the initial naphthalene-metabolizing reaction. The reactions in the absence of sulfate were not coupled to observable growth. Excretion of naphthalene-derived metabolites was also achieved in sulfate-rich medium upon addition of the protonophore carbonyl cyanide4-(trifluoromethoxy)phenylhydrazone or the ATPase inhibitor N,N'-dicyclohexylcarbodiimide. In conclusion, obstruction of electron flow and energy gain by sulfate limitation offers an explanation for the occurrence of naphthalene-derived metabolites in oil reservoirs, and provides a simple experimental tool for gaining insights into the anaerobic naphthalene oxidation pathway from an energetic perspective.

18.
Cancers (Basel) ; 12(8)2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32751846

RESUMO

A higher propensity of developing brain metastasis exists in triple-negative breast cancer (TNBC). Upon comparing the metastatic patterns of all breast cancer subtypes, patients with TNBC exhibited increased risks of the brain being the initial metastatic site, early brain metastasis development, and shortest brain metastasis-related survival. Notably, the development of brain metastasis differs from that at other sites owing to the brain-unique microvasculature (blood brain barrier (BBB)) and intracerebral microenvironment. Studies of brain metastases from TNBC have revealed the poorest treatment response, mostly because of the relatively backward strategies to target vast disease heterogeneity and poor brain efficacy. Moreover, TNBC is highly associated with the existence of cancer stem cells (CSCs), which contribute to circulating cancer cell survival before BBB extravasation, evasion from immune surveillance, and plasticity in adaptation to the brain-specific microenvironment. We summarized recent literature regarding molecules and pathways and reviewed the effects of CSC biology during the formation of brain metastasis in TNBC. Along with the concept of individualized cancer therapy, certain strategies, namely the patient-derived xenograft model to overcome the lack of treatment-relevant TNBC classification and techniques in BBB disruption to enhance brain efficacy has been proposed in the hope of achieving treatment success.

19.
Small ; 16(31): e2002089, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32602259

RESUMO

Spinel and perovskite with distinctive crystal structures are two of the most popular material families in electrocatalysis, which, however, usually show poor conductivity, causing a negative effect on the charge transfer process during electrochemical reactions. Herein, a highly conductive inverse spinel (Fe3 O4 ) and anti-perovskite (Ni3 FeN) hetero-structured nanocomposite is reported as a superior oxygen evolution electrocatalyst, which can be facilely prepared based on a one-pot synthesis strategy. Thanks to the strong hybridization between Ni/Fe 3d and N 2p orbitals, the Ni3 FeN is easily transformed into NiFe (oxy)hydroxide as the real active species during the oxygen evolution reaction (OER) process, while the Fe3 O4 component with low O-p band center relative to Fermi level is structurally stable. As a result, both high surface reactivity and bulk electronic transport ability are reached. By directly growing Fe3 O4 /Ni3 FeN heterostructure on freestanding carbon fiber paper and testing based on the three-electrode configuration, it requires only 160 mV overpotential to deliver a current density of 30 mA cm-2 for OER. Also, negligible performance decay is observed within a prolonged test period of 100 h. This work sheds light on the rational design of novel heterostructure materials for electrocatalysis.

20.
mSystems ; 5(3)2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32518199

RESUMO

The class Dehalococcoidia within the Chloroflexi phylum comprises the obligate organohalide-respiring genera Dehalococcoides, Dehalogenimonas, and "Candidatus Dehalobium." Knowledge of the unique ecophysiology and biochemistry of Dehalococcoidia has been largely derived from studies with enrichment cultures and isolates from sites impacted with chlorinated pollutants; however, culture-independent surveys found Dehalococcoidia sequences in marine, freshwater, and terrestrial biomes considered to be pristine (i.e., not impacted with organohalogens of anthropogenic origin). The broad environmental distribution of Dehalococcoidia, as well as other organohalide-respiring bacteria, supports the concept of active halogen cycling and the natural formation of organohalogens in various ecosystems. Dechlorination reduces recalcitrance and renders organics susceptible to metabolic oxidation by diverse microbial taxa. During reductive dechlorination, hydrogenotrophic organohalide-respiring bacteria, in particular Dehalococcoidia, can consume hydrogen to low consumption threshold concentrations (<0.3 nM) and enable syntrophic oxidation processes. These functional attributes and the broad distribution imply that Dehalococcoidia play relevant roles in carbon cycling in anoxic ecosystems.

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