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1.
Psychon Bull Rev ; 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33634356

RESUMO

How does the brain maintain spatial attention despite the retinal displacement of objects by saccades? A possible solution is to use the vector of an upcoming saccade to compensate for the shift of objects on eye-centered (retinotopic) brain maps. In support of this hypothesis, previous studies have revealed attentional effects at the future retinal locus of an attended object, just before the onset of saccades. A critical yet unresolved theoretical issue is whether predictively remapped attentional effects would persist long enough on eye-centered brain maps, so no external input (goal, expectation, reward, memory, etc.) is needed to maintain spatial attention immediately following saccades. The present study examined this issue with inhibition of return (IOR), an attentional effect that reveals itself in both world-centered and eye-centered coordinates, and predictively remaps before saccades. In the first task, a saccade was introduced to a cueing task ("nonreturn-saccade task") to show that IOR is coded in world-centered coordinates following saccades. In a second cueing task, two consecutive saccades were executed to trigger remapping and to dissociate the retinal locus relevant to remapping from the cued retinal locus ("return-saccade" task). IOR was observed at the remapped retinal locus 430-ms following the (first) saccade that triggered remapping. A third cueing task ("no-remapping" task) further revealed that the lingering IOR effect left by remapping was not confounded by the attention spillover. These results together show that predictive remapping leaves a robust attentional trace on eye-centered brain maps. This retinotopic trace is sufficient to sustain spatial attention for a few hundred milliseconds following saccades.

2.
Small ; : e2005357, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33615728

RESUMO

Despite numerous inherent merits of metal-organic frameworks (MOFs), structural fragility has imposed great restrictions on their wider involvement in many applications, such as in catalysis. Herein, a strategy for enhancing stability and enabling functionality in a labile Zr(IV)-MOF has been proposed by in situ porphyrin substitution. A size- and geometry-matched robust linear porphyrin ligand 4,4'-(porphyrin-5,15-diyl)dibenzolate (DCPP2- ) is selected to replace the 4,4'-(1,3,6,8-tetraoxobenzo[lmn][3,8]phenanthroline-2,7(1H,3H,6H,8H)-diyl)dibenzoate (NDIDB2- ) ligand in the synthesis of BUT-109(Zr), affording BUT-110 with varied porphyrin contents. Compared to BUT-109(Zr), the chemical stability of BUT-110 series is greatly improved. Metalloporphyrin incorporation endows BUT-110 MOFs with high catalytic activity in the photoreduction of CO2 , in the absence of photosensitizers. By tuning the metal species and porphyrin contents in BUT-110, the resulting BUT-110-50%-Co is demonstrated to be a good photocatalyst for selective CO2 -to-CO reduction, via balancing the chemical stability, photocatalytic efficiency, and synthetic cost. This work highlights the advantages of in situ ligand substitution for MOF modification, by which uniform distribution and high content of the incoming ligand are accessible in the resulting MOFs. More importantly, it provides a promising approach to convert unstable MOFs, which mainly constitute the vast MOF database but have always been neglected, into robust functional materials.

3.
Chemistry ; 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33522645

RESUMO

The signature reactivity of silacyclobutane (SCB) is their cycloaddition reactions with various π bonds. Recently we disclosed the first cases where SCBs reacted with both C sp2 -H and C sp3 -H σ bonds in an intramolecular fashion. Herein, we report that SCB is also an efficient reagent for C sp -H bond silylation. Thus, rhodium catalysed intermolecular reactions between SCBs and terminal alkynes produced a series of symmetrical and unsymmetrical tetraorganosilicons bearing a C sp -Si functionality. Our preliminary studied suggested that the reaction did not involve a cycloaddition pathway, but instead a direct activation of C sp -H bonds.

4.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 35(2): 234-240, 2021 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-33624480

RESUMO

Objective: To review the research progress of adipose-derived stem cells (ADSCs) in skin scar prevention and treatment. Methods: The related literature was extensively reviewed and analyzed. The recent in vitroand in vivo experiments and clinical studies on the role of ADSCs in skin scar prevention and treatment, and the possible mechanisms and biomaterials to optimize the effect of ADSCs were summarized. Results: As demonstrated by in vitro and in vivo experiments and clinical studies, ADSCs participate in the whole process of skin wound healing and may prevent and treat skin scars by reducing inflammation, promoting angiogenesis, or inhibiting (muscle) fibroblasts activity to reduce collagen deposition through the p38/mitogen-activated protein kinase, peroxisome proliferator activated receptor γ, transforming growth factor ß 1/Smads pathways. Moreover, bioengineered materials such as hydrogel from acellular porcine adipose tissue, porcine small-intestine submucosa, and poly (3-hydroxybutyrate-co-hydroxyvalerate) scaffold may further enhance the efficacy of ADSCs in preventing and treating skin scars. Conclusion: Remarkable progress has been made in the application of ADSCs in skin scar prevention and treatment. While, further studies are still needed to explore the application methods of ADSCs in the clinic.


Assuntos
Adipócitos , Cicatriz , Tecido Adiposo , Animais , Cicatriz/prevenção & controle , PPAR gama , Células-Tronco , Suínos
5.
J Orthop Surg Res ; 16(1): 106, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536047

RESUMO

PURPOSE: Elderly patients with intertrochanteric fractures exhibit post-traumatic hidden blood loss (HBL). This study aimed to evaluate the efficacy and safety of reducing post-traumatic HBL via early intravenous (IV) tranexamic acid (TXA) intervention in elderly patients with intertrochanteric fracture. METHODS: A prospective randomized controlled study was conducted with 125 patients (age ≥ 65 years, injury time ≤ 6 h) who presented with intertrochanteric fracture from September 2018 and September 2019. Patients in the TXA group (n = 63) received 1 g of IV TXA at admission, whereas those in the normal saline (NS) group (n = 62) received an equal volume of saline. Hemoglobin (Hgb) and hematocrit (Hct) were recorded at post-traumatic admission (PTA) and on post-traumatic days (PTDs) 1-3. HBL was calculated using the Gross formula. Lower extremity venous ultrasound was performed to detect venous thrombosis. RESULTS: Hgb on PTDs 2 and 3 was statistically higher in the TXA group than in the NS group. Hct and HBL on PTDs 1-3 were significantly less in the TXA group compared to the NS group. Preoperative transfusion rate was significantly lower in the TXA group compared with the NS group. There was no difference between the two groups with regard to the rates of complications. CONCLUSION: Early IV TXA intervention could reduce post-traumatic HBL and pre-operative transfusion rate in elderly patients with intertrochanteric fractures without increasing the risk of venous thrombosis.

6.
PLoS Biol ; 19(2): e3001113, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33626035

RESUMO

Transforming growth factor-ß (TGF-ß) signaling plays a critical role in promoting epithelial-to-mesenchymal transition (EMT), cell migration, invasion, and tumor metastasis. ΔNp63α, the major isoform of p63 protein expressed in epithelial cells, is a key transcriptional regulator of cell adhesion program and functions as a critical metastasis suppressor. It has been documented that the expression of ΔNp63α is tightly controlled by oncogenic signaling and is frequently reduced in advanced cancers. However, whether TGF-ß signaling regulates ΔNp63α expression in promoting metastasis is largely unclear. In this study, we demonstrate that activation of TGF-ß signaling leads to stabilization of E3 ubiquitin ligase FBXO3, which, in turn, targets ΔNp63α for proteasomal degradation in a Smad-independent but Erk-dependent manner. Knockdown of FBXO3 or restoration of ΔNp63α expression effectively rescues TGF-ß-induced EMT, cell motility, and tumor metastasis in vitro and in vivo. Furthermore, clinical analyses reveal a significant correlation among TGF-ß receptor I (TßRI), FBXO3, and p63 protein expression and that high expression of TßRI/FBXO3 and low expression of p63 are associated with poor recurrence-free survival (RFS). Together, these results demonstrate that FBXO3 facilitates ΔNp63α degradation to empower TGF-ß signaling in promoting tumor metastasis and that the TßRI-FBXO3-ΔNp63α axis is critically important in breast cancer development and clinical prognosis. This study suggests that FBXO3 may be a potential therapeutic target for advanced breast cancer treatment.

7.
Circ Res ; 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33593074

RESUMO

Rationale: Increased myocardial activity of Ca/calmodulin-dependent kinase II (CaMKII) leads to heart failure (HF) and arrhythmias. In Drosophila neurons, interaction of CaMKII with Ca/CaM-dependent serine protein kinase (CASK) has been shown to inhibit CaMKII activity, but the consequences of this regulation for HF and ventricular arrhythmias are unknown. Objective: We hypothesize that CASK associates with CaMKII in human and mouse hearts thereby limiting CaMKII activity, and that altering CASK expression in mice changes CaMKII activity accordingly, with functional consequences for contractile function and arrhythmias. Methods and Results: Immunoprecipitation revealed that CASK associates with CaMKII in human hearts. CASK expression is unaltered in HF but increased in patients with aortic stenosis. In mice, cardiomyocyte-specific knockout of CASK (CASK-KO) increased CaMKII auto-phosphorylation at the stimulatory T287 site, but reduced phosphorylation at the inhibitory T305/306 site. CASK-KO mice showed increased CaMKII-dependent sarcoplasmic reticulum (SR) Ca leak, reduced SR Ca-content, increased susceptibility to ventricular arrhythmias, greater loss of ejection fraction, and increased mortality after transverse aortic constriction. Intriguingly, stimulation of the cardiac glucagon-like peptide 1-receptor with exenatide increased CASK expression resulting in increased inhibitory CaMKII T305 phosphorylation, reduced CaMKII activity, and reduced SR Ca leak in WT but not CASK KO. Conclusions: CASK associates with CaMKII in the human heart. CASK-KO in mice increases CaMKII activity, leading to contractile dysfunction and arrhythmias. Increasing CASK expression reduces CaMKII activity, improves Ca handling and contractile function.

8.
ACS Nano ; 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33570920

RESUMO

A van der Waals bonded moiré bilayer formed by sequential growth of TiSe2 and TiTe2 monolayers exhibits emergent electronic structure as evidenced by angle-resolved photoemission band mapping. The two monolayers adopt the same lattice orientation but incommensurate lattice constants. Despite the lack of translational symmetry, sharp dispersive bands are observed. The dispersion relations appear distinct from those for the component monolayers alone. Theoretical calculations illustrate the formation of composite bands by coherent electronic coupling despite the weak interlayer bonding, which leads to band renormalization and energy shifts.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33609242

RESUMO

Immobilization of soil cadmium (Cd) has been the strategy mostly used in remediation of Cd-contaminated arable soil. However, Cd might be remobilized after the immobilization process through the acid-soluble and complexation effects. Development of agronomic management technologies to prevent soil Cd remobilization after the immobilization process was an important pathway to control the food safety of agricultural products in soils with the immobilized Cd. In this study, the ammonia (NH4+-N) and nitrate (NO3--N) forms with concentrations of 60, 90, and 150 mg-N kg-1 soil were performed for evaluating their effects on Cd remobilization with planted or unplanted treatments and Cd accumulation in tissues of edible amaranth (Liuye). With an initial soil palygorskite-bound fraction Cd concentration of 0.6 mg kg-1, bioavailable Cd in rhizosphere soils and Cd in crop shoots respectively increased from 11.4 to 20.6 µg kg-1 (dry soil weight) and 6.92 to 14.92 mg kg-1 (dry plant weight) in planted NH4+-N treatments, while significantly lower concentrations of bioavailable Cd in rhizosphere soils and Cd in crop tissues were observed with planted NO3--N treatments. Compared with that of planted NO3--N treatments, decreasing pH value (i.e., 7.64 to 7.18) induced by root proton efflux during the absorption of NH4+-N, enhancive organic/amino acid (oxalic acid, lactic acid, L-proline, and so on) secretion from roots, and increasing abundance of bacteria distributed in phyla Proteobacteria, Cyanobacteria, and Bacteroidetes with Cd mobilization ability in rhizosphere soils were the main reasons found in this study for the higher Cd remobilization in soils and Cd accumulation in crop under NH4+-N treatments. Moreover, the direct effect of NH4+-N on remobilization of immobilized Cd by upregulating the expression abundances of genes associated with pyruvate metabolism and amino acids metabolism was more significant than that of NO3--N. In summary, the use of NO3--N as preferred N fertilizer was more efficient to ensure the food safety of agricultural products than that of NH4+-N in Cd-contaminated arable soil after immobilization process.

10.
Theranostics ; 11(2): 768-788, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33391504

RESUMO

Rationale: The combination of medical and tissue engineering in neural regeneration studies is a promising field. Collagen, silk fibroin and seed cells are suitable options and have been widely used in the repair of spinal cord injury. In this study, we aimed to determine whether the implantation of a complex fabricated with collagen/silk fibroin (SF) and the human umbilical cord mesenchymal stem cells (hUCMSCs) can promote cerebral cortex repair and motor functional recovery in a canine model of traumatic brain injury (TBI). Methods: A porous scaffold was fabricated with cross-linked collagen and SF. Its physical properties and degeneration rate were measured. The scaffolds were co-cultured with hUCMSCs after which an implantable complex was formed. After complex implantation to a canine model of TBI, the motor evoked potential (MEP) and magnetic resonance imaging (MRI) were used to evaluate the integrity of the cerebral cortex. The neurologic score, motion capture, surface electromyography (sEMG), and vertical ground reaction force (vGRF) were measured in the analysis of motor functions. In vitro analysis of inflammation levels was performed by Elisa while immunohistochemistry was used in track the fate of hUCMSCs. In situ hybridization, transmission electron microscope, and immunofluorescence were used to assess neural and vascular regeneration. Results: Favorable physical properties, suitable degradation rate, and biocompatibility were observed in the collagen/SF scaffolds. The group with complex implantation exhibited the best cerebral cortex integrity and motor functions. The implantation also led to the regeneration of more blood vessels and nerve fibers, less glial fibers, and inflammatory factors. Conclusion: Implantation of this complex enhanced therapy in traumatic brain injury (TBI) through structural repair and functional recovery. These effects exhibit the translational prospects for the clinical application of this complex.

11.
Surg Endosc ; 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33398578

RESUMO

BACKGROUND: The robotic surgical system has several technical advantages over laparoscopic instruments. The technical feasibility and safety of robotic gastrectomy (RG) for gastric cancer have been reported by increasing number of studies. However, the long-term survival and recurrence outcomes after RG for locally advanced gastric cancer (AGC) have seldom been reported. This study aimed to compare long-term oncologic outcomes for patients with locally AGC after RG or laparoscopic gastrectomy (LG). METHODS: This study comprised 1170 patients underwent RG or LG, respectively, for locally AGC between March 2010 and February 2017. The primary outcome was the 3-year disease-free survival (DFS). The secondary endpoint included 3-year overall survival (OS) and recurrence patterns. One-to-one propensity score matching (PSM) was performed to reduce confounding bias. The outcomes were compared in PSM cohort. RESULTS: After PSM, a well-balanced cohort of 816 patients (408 in each group) were included in the analysis. The 3-year DFS rate was 76.2% in the robotic group and 70.1% in the laparoscopic group (P = 0.076). The 3-year OS rates was 76.7% in the robotic group and 73.3% in the laparoscopic group (P = 0.246). In the subgroup analyses for potential confounding variables, neither 3-year DFS nor 3-year OS survival were significantly different between the two groups (all P > 0.05). The two groups showed similar recurrence patterns within 3 years after surgery (P > 0.05). CONCLUSION: For patients with locally AGC, RG can result in comparable long-term survival outcomes without an increase in recurrence rate.

12.
Ann Palliat Med ; 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33474966

RESUMO

Zinner syndrome (ZS) is a rare anomaly of the Wolffian duct. We searched for case reports and case series to identify the most effective methods for examination and treatment. The PubMed/Medline, Embase, and Scopus databases were searched. Our searches yielded 160 case reports/case series and included 214 patients. The mean age at diagnosis was 29.35 years. The R:L distribution was 1:1. The most common symptoms were: frequency (24.3%), dysuria (23.1%) and perineal pain (20.2%) in ZS patients with clinical symptoms. The diagnostic investigations used most frequently were magnetic resonance imaging (MRI) (67.8%) and ultrasonography (65.0%). Maximum flow rate on uroflowmetry, semen ejaculate volume, sperm count, and sperm motility were significantly lower in patients with ZS. Among 193 patients with treatment details, 65.8% underwent surgery; 9.8% underwent aspiration; 24.3% were followed with observation. Two patients died after surgery; all other patients remained asymptomatic after surgery. Fifty-two patients had complications and comorbidities. In patients with ZS, the most common symptoms are seminal vesicle cyst enlargement and compression of the bladder, ureter, and reproductive system. The diagnosis mostly depends on radiological examination. Surgery may be effective, but complications may occur.

13.
Transl Psychiatry ; 11(1): 25, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33414390

RESUMO

Understanding the common dimension of mental disorders (such as anxiety, depression, and drug addiction) might contribute to the construction of biological frameworks (Research Domain Criteria, RDoC) for novel ways of treatment. One common dimension at the behavioral level observed across these disorders is a generalization. Testing generalization in serotonin transporter (5-HTT) knockout (KO) rats, an animal model showing depression/anxiety-like behaviors and drug addiction-like behaviors, could therefore provide more insights into this framework. We tested the outcome and stimulus generalization in wild-type (WT) and 5-HTT KO rats. Using a newly established touchscreen-based task, subjects directly responded to visual stimuli (Gabor patch images). We measured the response time and outcome in a precise manner. We found that 5-HTT KO rats processed visual information faster than WT rats during outcome generalization. Interestingly, during stimulus generalization, WT rats gradually responded faster to the stimuli as the sessions progressed, while 5-HTT KO rats responded faster than WT in the initial sessions and did not change significantly as the sessions progressed. This observation suggests that KO rats, compared to WT rats, may be less able to update changes in information. Taken together, KO 5-HTT modulates information processing when the environment changes.

14.
J Hazard Mater ; 409: 124921, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33421874

RESUMO

The discovery of plasmid-mediated tet(X) variants and efflux pump gene tmexCD1-toprJ1 conferring bacteria resistance to tigecycline has compromised glycylcycline as the last line of defense against infection, which poses serious threat to public health. Herein, real-time quantitative PCR was used to detect the abundance of seven tigecycline resistance genes (TRGs), including six tet(X) variants and tmexCD1-toprJ1, and insertion sequences ISCR2 and IS26. Then, the concentrations of nine antibiotics were quantified in fecal samples collected from 157 livestock farms in four Chinese provinces. TRGs, especially tet(X4), tmexCD1-toprJ1, and insertion sequences ISCR2 and IS26, were more abundant in chicken feces than in pig and cattle feces, suggesting the greater risk for the propagation of TRGs in chicken feces. Positive correlations (ρ = 0.3741-0.8275, P < 0.0001) between ISCR2/IS26 and TRGs (except tet(X1)) further demonstrated that ISCR2 mediates the transfer of tet(X3), tet(X4), and tet(X5) and that IS26 plays a certain role for the mobilization of tet(X4) and tmexCD1-toprJ1. Tetracyclines had no positive correlation with the abundance of TRGs (except tet(X1)), meanwhile florfenicol and tiamulin were positively correlated with TRGs. However, further research is needed to confirm whether or not florfenicol and tiamulin are potential driving factors of TRG accumulation.

15.
EMBO Rep ; 22(2): e47910, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33410264

RESUMO

Sleep homeostasis is crucial for sleep regulation. The role of epigenetic regulation in sleep homeostasis is unestablished. Previous studies showed that octopamine is important for sleep homeostasis. However, the regulatory mechanism of octopamine reception in sleep is unknown. In this study, we identify an epigenetic regulatory cascade (Stuxnet-Polycomb-Octß2R) that modulates the octopamine receptor in Drosophila. We demonstrate that stuxnet positively regulates Octß2R through repression of Polycomb in the ellipsoid body of the adult fly brain and that Octß2R is one of the major receptors mediating octopamine function in sleep homeostasis. In response to octopamine, Octß2R transcription is inhibited as a result of stuxnet downregulation. This feedback through the Stuxnet-Polycomb-Octß2R cascade is crucial for sleep homeostasis regulation. This study demonstrates a Stuxnet-Polycomb-Octß2R-mediated epigenetic regulatory mechanism for octopamine reception, thus providing an example of epigenetic regulation of sleep homeostasis.

16.
J Am Chem Soc ; 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33492147

RESUMO

The exploration of metal-organic frameworks (MOFs) through the rational design of building units with specific sizes, geometries, and symmetries is essential for enriching the structural diversity of porous solids for applications including storage, separation, and conversion. However, it is still a challenge to directly synthesize rare-earth (RE) MOFs with less connected clusters as a thermodynamically favored product. Herein, we report a systematic investigation on the influence of size, rigidity, and symmetry of linkers over the formation of RE-tetracarboxylate MOFs and uncover the critical role of linker desymmetrization in constructing RE-MOFs with eight-connected hexanuclear clusters. Our results on nine new RE-MOFs, PCN-50X (X = 1-9), indicate that utilization of trapezoidal or tetrahedral linkers provides accesses to traditionally unattainable RE-tetracarboxylate MOFs with 8-c hexanuclear nodes, while the introduction of square or rectangular linkers during the assembly of RE-MOFs based on polynuclear clusters typically leads to the MOFs constructed from 12-c nodes with underlying shp topology. By rational linker design, MOFs with two unprecedented (4, 8)-c nets, lxl and jun, can also be obtained. This work highlights linker desymmetrization as a powerful strategy to enhance MOFs' structural complexity and access MOF materials with nondefault topologies that can be potentially used for separation and catalysis.

17.
Environ Sci Technol ; 55(3): 1604-1614, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33427447

RESUMO

The occurrence of high-level tigecycline resistance tet(X) variant genes represents a new transferable resistance crisis to food safety and human health. Here, we investigated the abundance of tet(X)-variant genes [tet(X), tet(X1) to tet(X6)] in 33 samples collected from layer manures, manured/un-manured soils, and corresponding lettuce from three provinces in China. The results showed the occurrence of tet(X)/(X2), tet(X3), and tet(X4) in 24 samples. The detection rate of tet(X)/(X2) (23/24) is higher than that of tet(X3) (7/24) and tet(X4) (2/24), and tet(X)/tet(X2) and tet(X3) were found to be enriched and more abundant in most manured soil and several lettuce samples from manured soils than that from manure samples. Twenty six tigecycline-resistant bacteria were isolated, and tet(X)-variant genes were found to be disseminated not only by bacterial clone spreading but also via multidrug resistance plasmids. The total concentrations of tet(X)-variant genes showed significantly positive correlations (R = 0.683, p < 0.001) with ISCR2. Two veterinary tetracyclines (tetracycline and oxytetracycline) and other classes of antimicrobials (enrofloxacin, azithromycin, thiamphenicol, and florfenicol) showed significant correlations with the total concentrations of tet(X)-variant genes (R = 0.35-0.516, p < 0.05). The findings indicate the transmission of tet(X)-variant genes from layer manures to their receiving environmental soils and lettuce and highlight the contribution of veterinary antimicrobials to the spread of tet(X)-variant genes.

18.
Phytochemistry ; 182: 112589, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33352309

RESUMO

Schipropins A-J, a series of undescribed lanostane and cycloartane-type triterpenoids, were isolated from the stems and leaves of Schisandra propinqua. Their structures, most of which were characterized by C-3/C-4 cleavage, were elucidated by extensive spectroscopic analyses. Noteworthily, the absolute configurations of schipropins A, D-G, and I were determined by single-crystal X-ray diffraction. Furthermore, schipropins E and G were found to possess moderate NO production inhibitory activity.


Assuntos
Schisandra , Triterpenos , Cristalografia por Raios X , Estrutura Molecular , Folhas de Planta
19.
Clin Nucl Med ; 46(3): 231-232, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33323740

RESUMO

ABSTRACT: Metastases of mesenchymal chondrosarcoma to either the pancreas or the adrenal glands are rare. We hereby presented the 18F-FDG PET/CT images of a 21-year-old man initially diagnosed with chondrosarcoma of the right 11th rib. His 18F-FDG PET/CT scan after radiotherapy demonstrated 2 hypermetabolic lesions in the right adrenal gland and the pancreas, respectively. These 2 lesions were later confirmed by biopsy to be metastatic mesenchymal chondrosarcoma.

20.
J Dent ; 105: 103566, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33383100

RESUMO

OBJECTIVES: To compare the effect of bioavailable gluconate-chelated stannous fluoride (SnF2) toothpaste with control toothpastes for treatment of dentine hypersensitivity (DH) and enamel erosion. DATA AND SOURCES: A Procter & Gamble Oral Care archive of clinical studies was reviewed from 2000 to 2020. Eligible studies were Randomised Controlled Trials (RCTs) investigating bioavailable gluconate-chelated SnF2 toothpaste efficacy compared to controls in adult participants measured following tactile (Yeaple force) and/or evaporative stimuli (Schiff score) in-vivo, duration <2 months (DH); or by erosive toothwear (profilometry) from in-situ samples, duration 10-15 days. Two authors independently assessed eligibility and resolved disagreements by discussion. A meta-analysis was undertaken and Risk of Bias (RoB) assessed using the Cochrane collaboration RoB tool for randomized parallel-group and cross-over trials. RESULTS: Fourteen RCTs (1287 participants) assessed DH relief and Six RCTs (184 participants) enamel erosion protection. For DH SnF2 toothpastes provided a 57 % (evaporative air) and 142 % (tactile) benefit versus negative controls (sodium fluoride/monofluorophosphate, 8 studies; p < 0.001). Compared to positive controls (potassium nitrate or arginine, 6 studies), a 22 % advantage (p = 0.036) was seen for evaporative air. In erosion studies, SnF2 toothpastes provided an 83 % benefit versus control toothpastes (arginine or sodium fluoride; p < 0.001) with a change (95 %CI) in average surface profilometry level (µm) of -2.02(-2.85, -1.20). CONCLUSIONS: The use of these bioavailable SnF2 toothpastes, as part of a daily oral hygiene regimen, will provide patients with enamel erosion protection, combined with alleviation of DH pain when present, improving quality of life.

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