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1.
Chem Commun (Camb) ; 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894777

RESUMO

The coinciding effects of carbon defects and oxygen functional groups in porous graphene were demonstrated in this work. The species and distributions of oxygen functional groups evolved with the types of defects, especially those containing C[double bond, length as m-dash]O bonds mainly distributed along the edge of ring defects, and enhanced Na+ storage.

2.
Hum Cell ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919718

RESUMO

Gastric cancer (GC) is one of the most common malignancies worldwide. The prognosis of GC is unsatisfied owning to widespread metastasis. P21-activated kinase 1 (PAK1), a member of serine/threonine kinases, is associated with the progression of multiple types of human cancers. Here, we demonstrated that CDK4/6 inhibitor reduced GC cell viability and decreased PAK1 expression. Consistently, PAK1 ablation increased GC cell sensitivity exposed to CDK4/6 inhibitor and promoted DNA damage. We also revealed PAK1 depletion notably affected PDK1-AKT pathway, and PDK1 overexpression totally abrogated the effect of PAK1 deletion on DNA damage in GC cells. Additionally, PDK1 overexpression also rescued the increased GC cell sensitivity towards CDK4/6 inhibitor and the cell cycle arrest caused by PAK1 depletion. Our findings, therefore, suggested that PAK1 silencing increased sensitivity to CDK4/6 inhibition in gastric cancer cells via PDK1-AKT pathway. We, therefore, thought PAK1 as a promising therapeutic target for the treatment of CDK4/6 inhibitor-resistant gastric cancer.

3.
Exp Eye Res ; : 107922, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31923413

RESUMO

Besides apoptosis, necrosis can also occur in a highly regulated and genetically controlled manner, defined as regulated necrosis, which is characterized by a loss of cell membrane integrity and release of cytoplasmic content. Depending on the involvement of its signal pathway, regulated necrosis can be further classified as necroptosis, ferroptosis, pyroptosis and parthanatos. Numerous studies have demonstrated that regulated necrosis is involved in the pathogenesis of many diseases covering almost all organs including the brain, heart, liver, kidney, intestine, blood vessel, eye and skin, particularly myocardial infarction and stroke. Most recently, growing evidence suggests that multiple types of regulated necrosis contribute to the degeneration of retinal ganglion cells, retinal pigment epithelial cells or photoreceptor cells, which are the main pathologic features for glaucoma, age-related macular degeneration or retinitis pigmentosa, respectively. This review focuses on the involvement of necroptosis and ferroptosis in these blinding diseases.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31915294

RESUMO

Studies of the adult Drosophila midgut have led to many insights in our understanding of cell-type diversity, stem cell regeneration, tissue homeostasis, and cell fate decision. Advances in single-cell RNA sequencing provide opportunities to identify new cell types and molecular features. We used single-cell RNA sequencing to characterize the transcriptome of midgut epithelial cells and identified 22 distinct clusters representing intestinal stem cells, enteroblasts, enteroendocrine cells (EEs), and enterocytes. This unbiased approach recovered most of the known intestinal stem cells/enteroblast and EE markers, highlighting the high quality of the dataset, and led to insights on intestinal stem cell biology, cell type-specific organelle features, the roles of new transcription factors in progenitors and regional variation along the gut, 5 additional EE gut hormones, EE hormonal expression diversity, and paracrine function of EEs. To facilitate mining of this rich dataset, we provide a web-based resource for visualization of gene expression in single cells. Altogether, our study provides a comprehensive resource for addressing functions of genes in the midgut epithelium.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31897870

RESUMO

Operation performance and bacterial community structure of sulfur-based autotrophic denitrification (SAD) based on different sulfur sources served as electron donor was first parallelly compared among three sequencing batch reactors. Sulfur and sodium thiosulfate systems achieved similar operation performance and were superior to that of sodium sulfide. When the influent NO3--N concentration ranged from 50 to 150 mg/L, the effluent NO3--N concentrations of the sulfur and sodium thiosulfate systems were 0-5.99 mg/L and 0-4.52 mg/L, respectively, without NO2--N accumulation. However, when the effluent concentration of NO3--N in the sodium sulfide system was 0-10.38 mg/L, that of NO2--N in the effluent was 0-39.85 mg/L. In addition, participation of sulfur sources presented obvious pressure on the bacterial community structure based on the high-throughput sequencing. Microbial diversity results indicated that sludge with elemental sulfur as electron donor had the richest microbial diversity, followed by sodium thiosulfate and sodium sulfide. Moreover, sludge with elemental sulfur and sodium thiosulfate as electron donor demonstrated more similar community structure compared with the sludge that denitrified with sodium sulfide according to the microbial similarity analysis. The 9.34%, 24.3% and 29.6% of sequences could be assigned to potential SAD organisms from sludge denitrifying with elemental sulfur, sodium thiosulfate and sodium sulfide, respectively. Furthermore, all sludge denitrifying with different sulfur sources showed an enrichment of separate core functional microorganisms. This study could provide an insight into improving the understanding of SAD in engineering applications.

6.
ACS Appl Mater Interfaces ; 12(1): 780-788, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31849209

RESUMO

Customized deformable lithium-ion batteries (LIBs) have attracted interest in the emerging power systems for flexible and wearable electronics. However, a key challenge for developing these batteries is the fabrication of customized deformable electrodes that exhibit strong mechanical tolerance and robust electrochemical performance during deformation. Here, free-standing customized kirigami electrodes for deformable LIBs are fabricated by an evolutionary printing method with universal viscous electrode inks and a customizable polydimethylsiloxane template. The electrodes comprise lithium iron phosphate or lithium titanium oxide nanoparticles with a conductive carbon nanotubes/poly(vinylidene fluoride) scaffold, which is ideal for electron transfer. The compact microstructure and kirigami pattern endow the electrodes with superior mechanical robustness (over 500 stretch-release cycles) and resistance stability both in unstretched and stretched states. Finite element analysis and corresponding experiment tests reveal ultralow strain inside the materials, showing less than 3% strain even under 100% stretch ratio. With 500-times stretched electrodes, the full-cell LIBs can still deliver a considerable discharge capacity of average 94.5 mA h g-1 at 0.3 C after 100 discharge/charge cycles. The integration of such outstanding mechanical stability, excellent electrochemical performance, and simple printing method with accessible starting materials presents promising opportunities for customizing deformable components for flexible energy storage devices.

7.
Huan Jing Ke Xue ; 41(1): 345-352, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854936

RESUMO

A combined process of denitrification-partial nitritation-ANAMMOX based on a zeolite biological aerated filter (ZBAF) was applied to treat mature landfill leachate. We investigate the partial nitritation characteristics of the ZBAF and the nitrogen removal performance as well as the carbon removal performance of the combined process. Results showed that, based on the selective inhibition of nitrite oxidizing bacteria (NOB) by free ammonia (FA), the ZBAF could successfully achieve stable and efficient partial nitrification of mature landfill leachate, with an average nitrite accumulation rate (NAR) of 93.8% and a maximum nitrite production rate (NPR) of 1.659 kg·(m3·d)-1. After adding 700 mg·L-1 glucose to the influent, due to the synergistic effect of denitrification and anammoxidation, the combined process achieved its best nitrogen removal performance at a reflux ratio of 2.0 and hydraulic retention time (HRT) of 2.2 days. The average ammonia removal efficiency (ARE), total nitrogen removal efficiency (NRE), total nitrogen removal loading rate (NRR), and average chemical oxygen demand (COD) removal efficiency were 97.2%, 90.0%, 0.585 kg·(m3·d)-1, and 45.3%, respectively. Furthermore, the NRR of the anaerobic ammonium oxidation (ANAMMOX) process (NRRANA) reached 1.268 kg·(m3·d)-1. High-throughput sequencing technology was used to analyze the microbial community structure in each device. Results showed that denitrifiers (Paracoccus and Comamonas), ammonia-oxidizing bacteria (AOB) (Nitrosomonas), and ANAMMOX bacteria (Candidatus Kuenenia and Candidatus Anammoxoglobus) were the dominant bacteria in the UASB, ZBAF, and ANAMMOX reactor, respectively, which corresponded to the stable nitrogen removal performance of the combined process.


Assuntos
Reatores Biológicos/microbiologia , Desnitrificação , Nitrogênio/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Zeolitas , Bactérias/classificação , Bactérias/metabolismo , Filtração/métodos , Oxirredução
8.
Polymers (Basel) ; 11(12)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818008

RESUMO

The interface area of nano-dielectric is generally considered to play an important role in improving dielectric properties, especially in suppressing space charge. In order to study the role of interface area on a microscopic scale, the natural charge and injected charge movement and diffusion on the surface of pure LDPE and SiO2/LDPE nanocomposite were observed and studied by gradual discharge under electrostatic force microscope (EFM). It was detected that the charge in SiO2/LDPE nanocomposite moved towards the interface area and was captured, which indicates that the charge was trapped in the interface area and formed a barrier to the further injection of charge and improving the dielectric performance as a result. Moreover, pulsed electro-acoustic (PEA) short-circuited test after charge injection was carried out, and the change of total charge was calculated. The trend of charge decay in the EFM test is also generally consistent with that in PEA short-circuit test and can be used to verify one another. The results revealed the law of charge movement and verified the interface area can inhibit space charge injection in nano-dielectric at the microscale, which provides an experimental reference for relevant theoretical research.

9.
Chem Commun (Camb) ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31821402

RESUMO

A series of small molecule dyes demonstrate the feasibility of manipulating Near Infrared II emission by simply altering the donors' heteroatoms, which involved both electronegativity and intramolecular steric effects. Furthermore, these dyes show high resolution and stability for in vivo imaging after being complexed with human serum albumin.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31823476

RESUMO

Nonfullerene all-small-molecule organic solar cells (NFSM-OSCs) have shown a promising potential towards the commercialization of OSCs, owing to their unique advantages of high purity, easy synthesis and good reproducibility. However, great challenges in the modulation of phase separation morphology have limited their future development. Herein, two novel small molecular donors of BTEC-1F and BTEC-2F, derived from the small molecule DCAO3TBDTT, were designed and synthesized. While using Y6 as the acceptor, the devices based on non-fluorinated DCAO3TBDTT showed an open circuit voltage ( V oc ) of 0.804 V and a power conversion efficiency (PCE) of 10.64%. Mono-fluorinated BTEC-1F showed an increased V oc of 0.870 V and a PCE of 11.33%. More impressively, the fill factor (FF) of di-fluorinated BTEC-2F based NFSM-OSC was largely improved to 72.35% resulting in an impressive PCE of 13.34%, which was much higher than that of BTEC-1F (61.35%) and DCAO3TBDTT (60.95%). To the best of our knowledge, this is the highest reported PCE to date for NFSM-OSCs . BTEC-2F depicted a more compact molecular stacking and a lower crystallinity as revealed from characterization studies, which was beneficial for enhancing phase separation and carrier transport. Those results demonstrated an effective strategy to improve the performance of NFSM-OSCs via fluorination of small molecular donors and modulation of crystallinity deviation between donors and acceptors.

11.
Pathol Res Pract ; : 152731, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31785995

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies worldwide usually diagnosed at advanced stages which causes poor prognosis of patients. Therefore, novel diagnostic biomarkers and therapeutic targets are urgently needed. MATERIALS AND METHODS: miR-424-5p was identified through integrated analysis of three public databases. Loss-of-function experiments in HT29 and SW480 cells and mouse xenograft models were performed to explore the regulatory role of miR-424-5p in CRC. Bioinformatics analysis was used for predicting targets of miR-424-5p and its functional and pathway enrichment analysis. RESULTS: miR-424-5p expression was significantly upregulated in CRC tissues and cell lines and associated with prognosis of CRC patients. Experiments in vitro and in vivo showed miR-424-5p promotes CRC cell proliferation and metastasis by directly inhibiting SCN4B. Besides, CRC cells secret miR-424-5p into peripheral blood through exosomes and circulating exosomal miR-424-5p could discriminate CRC patients with early stage from healthy people with AUC value of 0.82. CONCLUSIONS: miR-424-5p serves as an oncogene in CRC and circulating exosomal miR-424-5p is a novel potential diagnostic biomarker of CRC patients.

12.
Biotechnol Bioeng ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31803933

RESUMO

Phenylpropionic acids are commonly used in the synthesis of pharmaceuticals, cosmetics, and fine chemicals. However, the synthesis of phenylpropionic acids faces the challenges of high cost of substrates and a limited range of products. Here, we present an artificially designed amino-group-transformation biocatalytic process, which uses simple phenols, pyruvate, and ammonia to synthesize diverse phenylpropionic acids. This biocatalytic cascade comprises an amino-group-introduction module and three amino-group-transformation modules, and operates in a modular assembly manner. Escherichia coli catalysts coexpressing enzymes from different modules achieve whole-cell simultaneous one-pot transformations of phenols into the corresponding phenylpropionic acids including (S)-α-amino acids, α-keto acids, (R)-α-amino acids, and (R)-ß-amino acids. With cofactor recycling, protein engineering, and transformation optimization, four (S)-α-amino acids, four α-keto acids, four (R)-α-amino acids, and four (R)-ß-amino acids are synthesized with good conversion (68%-99%) and high enantioselectivities (> 98%). Therefore, the amino-group-transformation concept provides a universal and efficient tool for synthesizing diverse products. This article is protected by copyright. All rights reserved.

13.
J Clin Lab Anal ; : e23109, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31804000

RESUMO

BACKGROUND: The pulmonary surfactant especially lipids in amniotic fluid can reflect the development stage of fetal lung maturity (FLM). However, the conventional lecithin/sphingomyelin (L/S) ratio method by thin layer chromatography (TLC) is insufficient and inconvenient for FLM prediction in clinical practice. METHODS: The amniotic fluid samples were collected from the pregnant women in labor or undergoing amniocentesis and analyzed for its lipid contents with the liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) method and the lamellar body count (LBC) method. To reveal the lipidomic profiling of different FLM stages, three groups of amniotic fluid samples including 8 from premature group (gestational week (GW) < 37), 10 from mature group (GW < 37), and 10 from mature group (GW > 38) were compared with the control group (n = 6) of 18 GWs separately. RESULTS: In the FLM prediction study, the sensitivity of the LC-HRMS method and LBC method was 91% and 73%, respectively; the specificity was 100% and 95%, respectively. The most significant metabolic pathway was linoleic acid metabolism between the premature group and the control group. Both glycerophospholipid metabolism and glycosylphosphatidylinositol-anchor biosynthesis were enriched in the mature groups. In search of potential FLM prediction markers in amniotic fluid, 8 phosphatidylcholines, 1 sphingomyelin, and 1 phosphatidylethanolamine were significantly increased in the mature groups compared with the premature group. CONCLUSION: An efficient LC-HRMS method for L/S ratio in predicting FLM was established. The linoleic acid metabolism may play an important role in the fetal lung development.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31814556

RESUMO

BACKGROUND: Ginsenoside Rh2 (Rh2) is a major biological component of ginseng that exerts anti-tumor activities in multiply cancers including Non-Small Cell Lung Cancers (NSCLCs). Rh2 also enhance the anti-tumor effects of various chemotherapy drugs including cisplatin at relatively low concentrations. Here, the mechanistic role of Rh2 in chemotherapy-treated NSCLCs will be investigated. METHODS: In this study, FACS, western blot and siRNA addition were used to analyze the role of Rh2 in cisplatin-treated lung adenocarcinoma A549 and H1299 cells. RESULTS: Subsequent observations indicated that Rh2 enhanced cisplatin-induced NSCLCs A549 and H1299 cells apoptosis. Cisplatin-induced productive autophagy was repressed by Rh2 in A549 cells. Rh2 also enhanced cisplatin cytotoxicity by elevating superoxide dismutase activity and repressing cisplatin-induced superoxide generation. Conversely, Rh2 was found to repress cisplatin-induced phosphorylation of epidermal growth factor receptor, phosphoinositide 3-kinase, protein kinase B, and autophagy. Cisplatin-induced Programmed Death-Ligand 1 (PD-L1) expression was repressed by Rh2 via the superoxide. CONCLUSION: These findings suggest that Rh2 enhanced the function of cisplatin by repressing superoxide generation, PD-L1 expression, and autophagy in lung adenocarcinoma cells.

15.
Medicine (Baltimore) ; 98(51): e18490, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31861033

RESUMO

To generate a nomogram to predict posthepatectomy liver failure (PHLF), we attempted to elucidate salient risk factors in patients with hepatocellular carcinoma (HCC).We performed a retrospective review of 665 patients with HCC who received hepatectomy in 2 academic institutions in China. Independent risk factors for PHLF were identified from putative demographic, intrinsic, biochemical, surgery-related, and volumetric data. A predictive nomogram was formulated based on relevant risk factors, and we compared this with existing models.We identified clinical signs of portal hypertension (P = .023), serum total bilirubin (P = .001), serum creatinine (P = .039), and intraoperative hemorrhage (P = .015) as being important risk factors in predicting PHLF. The nomogram had a C-index of 0.906 for the externally validated data. The nomogram displayed better predictive value than 2 of the other most cited models (C-indices of 0.641 and 0.616, respectively) in the current cohort. Additionally, we were able to patients into low- (<10%), intermediate- (10-30%), and high-risk (≥30%) groups based on the nomogram. This allows us to facilitate person-specific management.Here, we constructed a simple nomogram for prediction of PHLF in patients with HCC weighted by independent risk factors. Further prospective studies are required to confirm the predictive ability of our nomogram.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Falência Hepática/epidemiologia , Neoplasias Hepáticas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Idoso , China/epidemiologia , Feminino , Humanos , Falência Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Nomogramas , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
16.
Steroids ; 155: 108558, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31866544

RESUMO

Two new hydroperoxy steroids, namely, xidaosteroids A and B (1 and 2), along with five known related compounds 3-7, were isolated from the South China Sea gorgonian Rumphella sp.. Their structures were established by extensive spectroscopic analyses and comparison of the spectral data with those reported in the literature. In bioassay, compound 3 showed weak cytotoxicities against SNU-398 and Capan-1 cells.

17.
Life Sci ; 242: 117221, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31881224

RESUMO

AIMS: Endothelial cell (EC) tube formation is crucial for tumor angiogenesis, which becomes a target for chemotherapy. The anti-malaria agent dihydroartemisinin (DHA) inhibited tumor growth and angiogenesis. The aim of this study was to investigate the effects of DHA on EC tube formation and the underlying mechanisms. MATERIALS AND METHODS: Human umbilical vein endothelial cells (HUVECs) were cultured with different concentrations of DHA, and the tube formation was measured by in vitro angiogenesis assay. The protein levels of signal transducer and activator of transcription factor 3 (STAT3), phosphorylated STAT3 and fatty acid synthase (FASN) were detected by Western blotting. The gene expression of FASN was determined by real time-polymerase chain reaction (RT-PCR). The FASN siRNA and STAT3 (Y705D) vector were introduced into HUVECs by lipofectin transfection. KEY FINDINGS: DHA treatment inhibited tube formation, and the phosphorylation of STAT3 on Y705 of HUVECs. The expression of FASN was down-regulated by DHA and STAT3 inhibitor. The inhibitory effect of DHA on FASN expression in HUVECs was eliminated by co-treatment with the STAT3 inhibitor. Over-expression of STAT3 (Y705D) relieved the inhibitory effect of DHA on tube-formation and FASN expression. Under hypoxia condition, expression of FASN was up-regulated but inhibited by DHA treatment in HUVECs through suppression of STAT3 phosphorylation. SIGNIFICANCE: We demonstrate that DHA inhibits the protein level of FASN via attenuation of the Y705 phosphorylation of STAT3, and subsequently inhibits tube formation of HUVECs. Our results support the therapeutic potential of DHA on angiogenesis.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31847534

RESUMO

AIMS: In this original research communication, we assess the impact of shifting the window of glial HMOX1 overexpression in mice from early-to-mid-life to mid-to-late-life, resulting in two disparate conditions modeling schizophrenia (SCZ) and Parkinson disease (PD). Mesolimbic hyperdopaminergia is a widely accepted feature of SCZ, while nigrostriatal hypodopaminergia is the sine qua non of idiopathic PD. Although the advent of parkinsonian features in SCZ patients following treatment with anti-dopaminergic agents is intuitive, subtle features of parkinsonism commonly observed in young, drug-naïve schizophrenics is not. Similarly, emergent psychosis in PD subjects receiving levodopa replacement is not unusual, whereas spontaneous hallucinosis in non-medicated persons with idiopathic PD is enigmatic. Investigations using GFAP.HMOX1 mice may shed light on these clinical paradoxes. RESULTS: Astroglial HO-1 overexpression in mice throughout embryogenesis until 6 or 12 months of age resulted in hyperdopaminergia, hyperkinesia/stereotypy ameliorated with clozapine, deficient prepulse inhibition, reduced preference for social novelty, impaired nest-building and cognitive dysfunction reminiscent of SCZ. On the other hand, astroglial HO-1 overexpression between 8.5 and 19 months of age yielded a PD-like behavioral phenotype with hypodopaminergia, altered gait, locomotor incoordination and reduced olfaction. INNOVATION: We conjecture that region-specific disparities in the susceptibility of dopaminergic and other circuitry to the trophic and degenerative influences of glial HMOX1 induction may permit the concomitant expression of mixed SCZ and PD traits within affected individuals. CONCLUSION: Elucidation of these converging mechanisms may (i) help better understand disease pathogenesis and (ii) identify HO-1 as a potential therapeutic target in neurodevelopmental and neurodegenerative disorders.

19.
Mod Pathol ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31857681

RESUMO

Post-inflammatory mucosal hyperplasia and appendiceal diverticulosis simulate mucinous neoplasms, causing diagnostic confusion. Distinction between neoplasia and its mimics is particularly important since many authorities now consider all appendiceal mucinous neoplasms to be potentially malignant. The purpose of this study was to identify clinicopathologic and molecular features that may distinguish appendiceal mucinous neoplasms from non-neoplastic mimics. We retrospectively identified 92 mucinous lesions confined to the right lower quadrant, including 55 non-neoplastic examples of mucosal hyperplasia and/or diverticulosis and 37 low-grade neoplasms. Presenting symptoms, radiographic findings, appendiceal diameter, appearances of the lamina propria, non-neoplastic crypts, and epithelium, as well as mural changes were recorded. Twenty non-neoplastic lesions were subjected to KRAS mutational testing. Non-neoplastic appendices were smaller (p < 0.05) and more likely to present with symptoms of appendicitis (p < 0.05) than neoplasms. While post-inflammatory mucosal hyperplasia and diverticula often showed goblet cell-rich epithelium, extruded mucin pools, and patchy mural alterations with fibrosis, they always contained non-neoplastic crypts lined by mixed epithelial cell types and separated by lamina propria with predominantly preserved wall architecture. On the other hand, mucinous neoplasms lacked normal crypts (p < 0.05) and showed decreased lamina propria (p < 0.05) with diffusely thickened muscularis mucosae and lymphoid atrophy. Six (30%) non-neoplastic lesions contained KRAS mutations, particularly those containing goblet cell-rich hyperplastic epithelium. We conclude that distinction between neoplastic and non-neoplastic mucinous appendiceal lesions requires recognition of key morphologic features; KRAS mutational testing is an unreliable biomarker that cannot be used to assess biologic risk or confirm a diagnosis of neoplasia.

20.
Appl Opt ; 58(32): 8743-8750, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31873651

RESUMO

We report the development of an improved spherical mirror multipass-cell-based interband cascade laser (ICL) spectrometer for ambient formaldehyde (HCHO) detection. The multipass cell consists of two easily manufactured spherical mirrors that are low cost, and have a simple structure, large mirror area utilization, and dense spot pattern. Optical interference caused by the multipath cell was largely reduced, resulting in good sensitivity. Using wavelength modulation spectroscopy (WMS), a detection precision (${1} \sigma $1σ) of 51 pptv in 10 s was achieved with an absorption pathlength of 96 m, which compared favorably with the performance of other state-of-the-art instruments. The precision can be further improved by using a long absorption pathlength configuration and by removing fringe-like optical noise caused by the collimation lens. Ambient application of the developed spectrometer was demonstrated.

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