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1.
BMC Musculoskelet Disord ; 21(1): 13, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31914975

RESUMO

BACKGROUND: Mucosal melanomas are rare and have a high potential for metastasizing. Surgical resection is the treatment of choice for single distant metastases. Malignant melanoma usually shows the highest uptake of fluorine-18 fluorodeoxyglucose (18F-FDG). 18F- FDG positron emission tomography /computed tomography (PET/CT) is usually used for melanoma staging. An extensive literature review revealed only 4 published case reports and an original paper involving 8 cases (12 cases in total) of patients with skin melanomas in whom pigmented villous nodular synovitis (PVNS) mimicked metastatic melanoma, however, none of the melanomas reported were of rectal mucosal origin. CASE PRESENTATION: A 60-year-old woman presented with recent diagnosis of rectal mucosal melanoma, two additional 18F-FDG-avid lesions in the left ankle and left foot were detected on 18F-FDG PET/CT. Metastases were initially suspected; however, the final diagnosis was PVNS. CONCLUSIONS: This is the first report of PVNS mimicking metastases on 18F-FDG PET/CT in a patient with rectal mucosal melanoma. Although high 18F-FDG-avid lesions in patients with rectal mucosal melanoma are highly suspected to be metastasis and warrant an meticulous examination, the present case is a reminder that in such patients, not all lesions with high 18F-FDG uptake, especially those near a joint, are metastases and that more extensive resection is unnecessary.

2.
Neuron ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31786011

RESUMO

How adult neurons coordinate lipid metabolism to regenerate axons remains elusive. We found that depleting neuronal lipin1, a key enzyme controlling the balanced synthesis of glycerolipids through the glycerol phosphate pathway, enhanced axon regeneration after optic nerve injury. Axotomy elevated lipin1 in retinal ganglion cells, which contributed to regeneration failure in the CNS by favorably producing triglyceride (TG) storage lipids rather than phospholipid (PL) membrane lipids in neurons. Regrowth induced by lipin1 depletion required TG hydrolysis and PL synthesis. Decreasing TG synthesis by deleting neuronal diglyceride acyltransferases (DGATs) and enhancing PL synthesis through the Kennedy pathway promoted axon regeneration. In addition, peripheral neurons adopted this mechanism for their spontaneous axon regeneration. Our study reveals a critical role of lipin1 and DGATs as intrinsic regulators of glycerolipid metabolism in neurons and indicates that directing neuronal lipid synthesis away from TG synthesis and toward PL synthesis may promote axon regeneration.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31793003

RESUMO

BACKGROUND: The power of inhibin B to predict competent spermatogenesis is not fully understood. The aims of this study were to identify the reliable reference range of inhibin B among normozoospermic men in China and to evaluate the diagnostic accuracy of serum inhibin B level as a complementary predictor of successful sperm retrieval in patients with azoospermia. METHODS: This was a cross-sectional study. The male partners of 30 613 infertile couples who visited our hospital were investigated between March 2017 and March 2019. We analysed semen parameters, serum levels of reproductive hormones (inhibin B, FSH and testosterone) and sperm retrieval results from PESA/TESE in Chinese men. RESULTS: The normal reference range of inhibin B was 87.42-299.93 pg/mL among men with normozoospermia in China. Inhibin B levels were negatively correlated with age (r = -.111; P < .001) but positively correlated with total sperm counts in the overall population, reference group and case group (r = .311, r = .208 and r = .444, respectively; P < .001). Stepwise multiple regression analyses revealed that compared with the FSH and testosterone levels, the inhibin B level had the closest relationship with the total sperm count. The best cutoff value of inhibin B for predicting the retrieval outcome of testicular/epididymal sperm was >77.72 pg/mL (sensitivity = 59.14%, specificity = 92.00% and AUC = 0.801). The inhibin B:FSH ratio (cutoff value > 6.98, sensitivity = 56.99%, specificity = 96.00% and AUC = 0.814) performed better than either the inhibin B level or the FSH level alone. CONCLUSION: A new reference range for serum inhibin B was established in China. However, neither serum inhibin B, FSH nor their ratio is adequate for men to decide whether to undergo PESA/TESE to determine the adequacy of spermatogenesis.

4.
Medicine (Baltimore) ; 98(49): e18281, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31804369

RESUMO

RATIONALE: Cardiac papillary fibroelastoma is a small, benign endocardial tumor, while it is clinically important because of its strategic position and propensity for causing embolic events and hemodynamic complications. PATIENT CONCERNS: A 59-year-old female presented our hospital for investigation and treatment of a sudden onset of syncope lasted about 2 minutes. DIAGNOSES: Cardiac papillary fibroelastoma arising from left inferior pulmonary vein in left atrium. INTERVENTIONS: The tumor was successfully removed by cardiac surgery. OUTCOMES: The patient's postoperative course was uneventful, and she was discharged 10 days after surgery. The patient remained free of neurologic deficits and had no evidence of residual or recurrence of tumor with echocardiography during 1 year of follow-up. LESSONS: Cardiac papillary fibroelastoma is a benign tumor, with increased risk of thromboembolic events. It is often diagnosed in patients with echocardiography by chance or after a neurologic event. Complete surgical resection should be considered when the patient is indicated and the long-term postoperative prognosis is excellent.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31862719

RESUMO

The emergence of the plasmid-mediated colistin resistance gene mcr-1 has led to serious multidrug-resistant (MDR) Enterobacteriaceae infections, which are a great threat to the clinic. This study aims to find an inhibitor of MCR-1 to recall the use of polymyxins against MDR Enterobacteriaceae infections. Here, we determined that the natural compound honokiol could enhance the efficacy of polymyxins against MDR Enterobacteriaceae infections by a checkerboard MIC (minimum inhibitory concentration) assay, time-kill assay, combined disk test, western blot, molecular simulation dynamics and mouse infection models. The MIC results indicated that honokiol can recover the sensitivity of polymyxins against MCR-1-positive Klebsiella pneumoniae and Escherichia coli (FIC index from 0.09±0.00 to 0.27±0.06). Based on time-kill curve analysis, all the tested bacteria were killed within 1 h following the combined therapy with honokiol and polymyxins. Molecular simulation dynamics results suggested that honokiol directly binds to the MCR-1 active region, reducing the biological activity of MCR-1. The combination of honokiol and polymyxins could increase the 40 % protection rate and reduce the bacterial load on the thigh muscles of mice. Our study indicates that honokiol is a predominant natural compound whose combination therapy with polymyxins is very promising in future treatment options for MCR-1-positive Enterobacteriaceae infections.Importance In the present study, honokiol can effectively inhibit the activity of MCR-1 and is extremely almost no cytotoxicity to MH-S cells. According to our results, in combination with honokiol and polymyxin, there is a clear synergistic effect against MCR-1-positive Enterobacteriaceae in vitro Combination therapy also shows a powerful therapeutic effect in vivo, which can significantly improve the mice livability, reduces the load of bacteria and reduces pathological change. This combined therapy of small molecule compounds and antibiotics maybe not continue to induce new bacterial resistance due to MCR-1 targeted by honokiol is not indispensable for the bacterial viability, on the other hand, it can reduce the dosage of combined antibiotics, and it is also a promising alternative therapy for the treatment of drug-resistant infections in the future.

7.
J Exp Clin Cancer Res ; 38(1): 451, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31690336

RESUMO

In the original publication of this article [1], Fig. 3 is wrong, but does not affect discussions and conclusions drawn in the article.

8.
Biosens Bioelectron ; : 111881, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31780408

RESUMO

In enzyme-based immunoassys, the use of natural enzyme has been remarkably restricted by the inconvenience in preparation and storage, especially for point-of-care testing. Nanozymes, which can mimic the functions of natural enzymes, have been regarded as promising alternatives due to their robust stability and convenience in fabrication. Here we fabricated one-dimensional Fe3O4@C core-shell nanostructures via a solvent-thermal method. Thus prepared nanocomposites showed excellent peroxidase-like activity, capable of catalyzing chromogenic substrates into colored products in the presence of H2O2. We then developed a nanozyme-linked aptamer sorbent assay (NLASA) in a sandwich format, in which the as-prepared Fe3O4@C nanowires were employed as catalytic labels for colorimetric detection by naked eyes. In the detection of platelet-derived growth factor BB (PDGF-BB), this assay reliably exhibited detection limits as low as 10 fM, with a working range from 10 fM to 100 nM. By incorporating G-quadruplex-hemin DNAzyme with Fe3O4@C nanowires, the detection limit could be further lowered to 50 aM. The detection limit of PDGF-BB in 50% human serum was 100 fM. This ultrasensitive, cost-effective and easy-to-operate sensing platform offers new opportunities for protein detection in clinical diagnosis.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31758639

RESUMO

OBJECTIVE: Hip fractures have serious consequences, including a one-year mortality rate of 30%. Population-based studies on hip fractures in individuals with systemic lupus erythematosus (SLE) are scarce. This study assesses the independent risk of hip fractures in patients with newly diagnosed SLE compared to the general population, accounting for baseline and time-varying confounders. METHODS: A cohort of all patients with incident SLE who received healthcare between January 1, 1997 and March 31, 2015 was assembled. The outcome was first hip fracture after study entry. Non-SLE individuals were randomly selected from the general population and matched (5:1) to those with SLE on age-, sex-, and index year. Cumulative incidence was produced after accounting for competing risks of death. Marginal structural Cox models were used to estimate the impact of SLE on hip fractures, adjusting for baseline and time-dependent covariates (i.e., glucocorticoid use and number of outpatient, inpatient and rheumatologist visits). RESULTS: Among 5,047 incident SLE and 25,235 non-SLE individuals (86% female, mean age 40), we found 73 and 272 hip fractures during 78,915 and 395,427 person-years, respectively. The crude incidence rate ratio was 1.34 (95% CI; 1.02-1.75). After adjusting for baseline covariates, the hazard ratio (HR) was 1.86 (95% CI; 1.37-2.52). The HR after further adjustment for time-dependent covariates remained significant (HR=1.62 [95% CI; 1.06-2.48]). CONCLUSION: Patients with newly diagnosed SLE have a 62% increased risk of hip fractures compared to non-SLE individuals. This result has important implications for prevention of osteoporosis in SLE patients that may lead to hip fractures.

10.
J Exp Clin Cancer Res ; 38(1): 444, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31666103

RESUMO

In the original publication of this article [1], there are mistakes in Fig. 3c and Fig. 3e.

11.
Free Radic Biol Med ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31669347

RESUMO

Energy metabolism plays important roles in the growth and survival of cancer cells. Here, we find a newly synthesized flavonoid named GL-V9, which inhibits glycolysis and induces apoptosis of human breast cancer cell lines, and investigate the underlying mechanism. Results show that hexokinase II (HKII) plays important roles in the anticancer effects of GL-V9. GL-V9 not only downregulates the expression of HKII in MDA-MB-231 and MCF-7 cells, but also induces dissociation of HKII from voltage-dependent anion channel (VDAC) in mitochondria, resulting in glycolytic inhibition and mitochondrial-mediated apoptosis. The dissociation of mitochondrial HKII is attributed to GSK-3ß-induced phosphorylation of mitochondrial VDAC. Our in vivo experiments also show that GL-V9 significantly inhibits the growth of human breast cancer due to activation of GSK-3ß and inactivation of AKT. Thus, GL-V9 induces cytotoxicity in breast cancer cells via disrupting the mitochondrial binding of HKII. Our works demonstrate the significance of metabolic regulators in cancer growth and offer a fresh insight into the molecular basis for the development of GL-V9 as a candidate for breast carcinoma treatment.

12.
Water Sci Technol ; 80(5): 970-978, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31746804

RESUMO

A monolithic-porous carbon (MPC) was fabricated by carbonizing a pine rod, and then the oxidized monolithic-porous carbon (O-MPC) was obtained via alkaline heat treatment of MPC. With well-ordered axial channels (diameters were 6-14 µm and 40-50 µm) and oxygen-containing functional groups, O-MPC as a flow-through cathode exhibited good capability in continuously generating H2O2 (422 µmol/L) via oxygen reduction. O-MPC and additional Fe2+ composed an electro-Fenton system and the performance of the system in degradation of organic pollutants was evaluated. For phenol, bisphenol A or sulfamethoxazole at initial concentration of 10 mg/L the removal efficiency reached 74%-82% in a hydraulic retention time of 100 seconds, nearly close to that of the homogeneous Fenton process (90%). This efficiency may be maintained for at least 10 hours, indicating a good stability of O-MPC. The results demonstrate the potential of O-MPC as a flow-through electrode to realize homogeneous-like degradation of organic pollutants in wastewater.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Carbono , Eletrodos , Peróxido de Hidrogênio , Ferro , Oxirredução , Porosidade
14.
Chemosphere ; 241: 124927, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31590029

RESUMO

Plasma treated g-C3N4 (PT-g-C3N4) was obtained by a simple and rapid DBD plasma modification process on the pristine g-C3N4. Compared with the pristine g-C3N4, the grain size of the PT-g-C3N4 decreased from 99.2 nm to 57.2 nm, the specific surface area and the pore volume increased by 15% and 33.8%, respectively. Oxygen-containing groups such as -NO2 and -COOH were observed to form on the surface of PT-g-C3N4 so the hydrophilic property of PT-g-C3N4 was much higher than that of pristine g-C3N4. More importantly, the photocatalytic H2O2 production activity of PT-g-C3N4 was significantly improved on account of the treatment in plasma atmosphere for only 5 min, the H2O2 yield of which was about 13 times that of the pristine g-C3N4. Our finding is not only of great significance for effectively promoting the production of H2O2 under mild conditions, but also proposes an innovative DBD plasma method to modify the g-C3N4 photocatalyst, which effectively promotes the improvement of photocatalytic activity and provides valuable insights for catalyst modification studies.

15.
CMAJ ; 191(39): E1070-E1077, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570545

RESUMO

BACKGROUND: Allopurinol is commonly prescribed for gout, and its clinical use may expand with ongoing trials assessing its potential cardiorenal benefits. Because heart disease has been suggested to be a risk factor for allopurinol-associated severe cutaneous adverse reactions, we sought to confirm this association in a Canadian general population cohort. METHODS: We used population data from British Columbia, Canada, to identify all incident allopurinol users between 1997 and 2015. We examined the association between heart disease (ischemic heart disease and heart failure) and the risk of hospital admission for severe cutaneous adverse reactions, adjusting for known and purported risk factors. We also evaluated the joint effects of combined clinical and demographic risk factors. RESULTS: Among 130 325 allopurinol initiators, 109 hospital admissions occurred for allopurinol-associated severe cutaneous adverse reactions. The multivariable relative risk among those with heart disease was 1.55 (95% confidence interval 1.01-2.37). Patients with heart disease and chronic kidney disease who were started on an allopurinol dosage of greater than 100 mg/d had an 11-fold higher risk. Allopurinol initiation at a lower dosage among patients with heart disease and chronic kidney disease resulted in a fivefold reduction in risk. Older women with heart disease from regions with large Asian populations had a 23-fold higher risk of allopurinol-associated severe cutaneous adverse reactions than younger men without heart disease from other regions. INTERPRETATION: Heart disease is independently associated with risk of allopurinol-associated severe cutaneous adverse reactions, similar to chronic kidney disease, and low-dosage allopurinol initiation may substantially mitigate this risk. Risk factors for these rare but serious reactions should be considered when initiating allopurinol.

16.
Int J Mol Sci ; 20(20)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614621

RESUMO

Cells of Microcystis are associated with heterotrophic bacteria and organized in colonies in natural environment, which are basic elements in the mass occurrence of cyanobacterial species. Analyzing these colonies by using metagenomics is helpful to understand species composition and relationship. Meanwhile, the difference in population abundance among Microcystis colonies could be used to recover genome bins from metagenome assemblies. Herein, we designed a pipeline to obtain high-quality genomes of mutualistic bacteria from single natural Microcystis colonies. Single colonies were lysed, and then amplified by using multiple displacement amplification to overcome the DNA quantity limit. A two-step assembly was performed after sequencing and scaffolds were grouped into putative bins based on their differential-coverage among species. We analyzed six natural colonies of three prevailing Microcystis species from Lake Taihu. Clustering results proved that colonies of the same species were similar in the microbial community composition. Eight putative population genome bins with wide bacterial diversity and different GC content were identified based on coverage difference among colonies. At the phylum level, proteobacteria was the most abundant besides cyanobacteria. Six of the population bins were further refined into nearly complete genomes (completeness > 90%).

17.
Nano Lett ; 19(12): 8565-8571, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31581774

RESUMO

High-temperature thermal photonics presents unique challenges for engineers as the database of materials that can withstand extreme environments are limited. In particular, ceramics with high temperature stability that can support coupled light-matter excitations, that is, polaritons, open new avenues for engineering radiative heat transfer. Hexagonal boron nitride (hBN) is an emerging ceramic 2D material that possesses low-loss polaritons in two spectrally distinct mid-infrared frequency bands. The hyperbolic nature of these frequency bands leads to a large local density of states (LDOS). In 2D form, these polaritonic states are dark modes, bound to the material. In cylindrical form, boron nitride nanotubes (BNNTs) create subwavelength particles capable of coupling these dark modes to radiative ones. In this study, we leverage the high-frequency optical phonons present in BNNTs to create strong mid-IR thermal antenna emitters at high temperatures (938 K). Through direct measurement of thermal emission of a disordered system of BNNTs, we confirm their radiative polaritonic modes and show that the antenna behavior can be observed even in a disordered system. These are among the highest-frequency optical phonon polaritons that exist and could be used as high-temperature mid-IR thermal nanoantenna sources.

20.
Arthritis Rheumatol ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31486212

RESUMO

OBJECTIVE: To examine modifiable risk factors in relation to the presence of hyperuricemia and to estimate the proportion of hyperuricemia cases in the general population that could be prevented by risk factor modification, along with estimates of the variance explained. METHODS: Using data obtained from 14,624 adults representative of the US civilian noninstitutionalized population, we calculated adjusted prevalence ratios for hyperuricemia, population attributable risks (PARs), and the variance explained according to the following 4 factors: body mass index (BMI; ≥25 kg/m2 ), alcohol intake, nonadherence to a Dietary Approaches to Stop Hypertension (DASH) diet, and diuretic use. RESULTS: BMI, alcohol intake, adherence to a DASH-style diet, and diuretic use were all associated with serum urate levels and the presence of hyperuricemia in a dose-dependent manner. The corresponding PARs of hyperuricemia cases for overweight/obesity (prevalence 60%), nonadherence to a DASH-style diet (prevalence 82%), alcohol use (prevalence 48%), and diuretic use (prevalence 8%) were 44% (95% confidence interval [95% CI] 41%, 48%), 9% (95% CI 3%, 16%), 8% (95% CI 5%, 11%), and 12% (95% CI 11%, 14%), respectively, whereas the corresponding variances explained were 8.9%, 0.1%, 0.5%, and 5.0%. Our simulation study showed the variance nearing 0% as exposure prevalence neared 100%. CONCLUSION: In this nationally representative study, 4 modifiable risk factors (BMI, the DASH diet, alcohol use, and diuretic use) could be used to individually account for a notable proportion of hyperuricemia cases. However, the corresponding serum urate variance explained by these risk factors was very small and paradoxically masked their high prevalences, providing real-life empirical evidence for its limitations in assessing common risk factors.

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