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1.
Opt Lett ; 49(15): 4238-4241, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090903

RESUMO

Exotic dipolar radiation with zero light emission in one direction but maximal light emission in the opposite direction was envisioned by Huygens in 1690, and it could emerge in vacuum if the ratio between the source's electric and magnetic dipole moments fulfills the Kerker condition as revealed by Kerker in 1983. Due to its intricate connection with both the Huygens principle and Kerker condition, this radiation phenomenon is suggested to be termed as dipolar Huygens-Kerker radiation, and at this moment, the ratio is termed as the Huygens-Kerker ratio. However, the dipolar Huygens-Kerker radiation remains underexplored in non-vacuum matters, inside which the source locates, especially for surface waves. Here we find that the dipolar Huygens-Kerker radiation of surface waves in principle could occur in non-vacuum matters and is essentially featured with the same normalized radiation pattern, which is closely related to the inclination factor that appears in the Fresnel-Kirchhoff diffraction theory. Moreover, the corresponding Huygens-Kerker ratio is intrinsically determined by the phase velocity of excited surface waves. To be specific, the Huygens-Kerker ratio is proportional to the phase velocity for transverse-magnetic surface waves but becomes inversely proportional to the phase velocity for transverse-electric surface waves.

2.
Pediatr Blood Cancer ; 71(9): e31099, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38845144

RESUMO

BACKGROUND: The clinical relevance of BRAF-V600E alleles in peripheral blood mononuclear cells (PBMCs) and the prognostic impact of the mutants in cell-free (cf) and PBMC DNAs of Langerhans cell histiocytosis (LCH) have not been fully clarified in pediatric LCH. METHODS: We retrospectively determined the levels of BRAF-V600E mutation in paired plasma and PBMC samples at the time of diagnosis of LCH. Subsequently, we performed a separate or combined analysis of the clinical and prognostic impact of the mutants. RESULTS: We assessed BRAF-V600E mutation in peripheral blood from 94 patients of childhood LCH. Our data showed that cfBRAF-V600E was related to young age, multiple-system (MS) disease, involvements of organs with high risk, increased risk of relapse, and worse progression-free survival (PFS) of patients. We also observed that the presence of BRAF-V600E in PBMCs at baseline was significantly associated with MS LCH with risk organ involvement, younger age, and disease progression or relapse. The coexisting of plasma(+)/PBMC(+) identified 36.2% of the patients with the worst outcome, and the hazard ratio was more significant than either of the two alone or neither, indicating that combined analysis of the mutation in plasma and PBMCs was more accurate to predict relapse than evaluation of either one. CONCLUSIONS: Concurrent assessment of BRAF-V600E mutation in plasma and PBMCs significantly impacted the prognosis of children with LCH. Further prospective studies with larger cohorts need to validate the results of this study.


Assuntos
Histiocitose de Células de Langerhans , Leucócitos Mononucleares , Mutação , Proteínas Proto-Oncogênicas B-raf , Humanos , Histiocitose de Células de Langerhans/genética , Histiocitose de Células de Langerhans/mortalidade , Histiocitose de Células de Langerhans/patologia , Histiocitose de Células de Langerhans/terapia , Histiocitose de Células de Langerhans/tratamento farmacológico , Histiocitose de Células de Langerhans/sangue , Proteínas Proto-Oncogênicas B-raf/genética , Masculino , Feminino , Estudos Retrospectivos , Criança , Pré-Escolar , Prognóstico , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/metabolismo , Lactente , Adolescente , Seguimentos , Taxa de Sobrevida
3.
Arch Pathol Lab Med ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38749502

RESUMO

CONTEXT.­: Langerhans cell histiocytosis (LCH) is a rare myeloid neoplasm that predominantly affects young children. OBJECTIVE.­: To investigate genetic alterations and their correlation with clinical characteristics and prognosis in pediatric LCH. DESIGN.­: We performed targeted sequencing to detect mutations in LCH lesions from pediatric patients. RESULTS.­: A total of 30 genomic alterations in 5 genes of the MAPK pathway were identified in 187 of 223 patients (83.9%). BRAF V600E (B-Raf proto-oncogene, serine/threonine kinase) was the most common mutation (51.6%), followed by MAP2K1 (mitogen-activated protein kinase kinase 1) alterations (17.0%) and other BRAF mutations (13.0%). ARAF (A-Raf proto-oncogene, serine/threonine kinase) and KRAS (KRAS proto-oncogene, GTPase) mutations were relatively rare (2.2% and 0.9%, respectively). Additionally, FNBP1 (formin-binding protein 1)::BRAF fusion and MAP3K10 (mitogen-activated protein kinase kinase 10) mutations A17T and R823C were identified in 1 case each, with possible constitutive activation of ERK1/2 phosphorylation. BRAF V600E was more frequent in patients with risk organ involvement, while MAP2K1 mutation was more prevalent in patients with single-system LCH (P = .001). BRAF V600E was associated with craniofacial bone, skin, liver, spleen, and ear involvement (all P < .05). Patients with other BRAF mutations had a higher proportion of spinal column involvement (P = .006). Univariate analysis showed a significant difference in progression-free survival among the 4 molecular subgroups for patients treated with first-line therapy (P = .02). According to multivariate analysis, risk organ involvement was the strongest independent adverse prognostic factor (hazard ratio, 8.854; P < .001); BRAF or MAP2K1 mutation was not an independent prognostic factor. CONCLUSIONS.­: Most pediatric patients with LCH carry somatic mutations involving the MAPK pathway, correlating with clinical characteristics and outcomes for first-line chemotherapy.

4.
Cancer Cell Int ; 24(1): 169, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734646

RESUMO

Forkhead box E1 (FOXE1), also known as thyroid transcription factor 2 (TTF-2), belongs to a large family of forkhead transcription factors. It plays important roles in embryogenesis, cell growth, and differentiation. Cancer-specific FOXE1 hypermethylation events have been identified in several cancers. However, the expression and function of FOXE1 in the tumorigenesis of colorectal cancer remain still unknown. In this study, we examined FOXE1 expression and methylation in normal colon mucosa, colorectal cancer (CRC) cell lines, and primary tumors by immunohistochemistry, semi-quantitative RT-PCR, methylation-specific PCR, and bisulfite genomic sequencing. We found that FOXE1 was frequently methylated and silenced in CRC cell lines and was downregulated in CRC tissues compared with paired adjacent non-tumor tissues. Meanwhile, low FOXE1 expression was significantly correlated with lymph node metastasis and advanced TNM stages, indicating its potential as a tumor marker. Subsequently, we established colon cancer cell lines with stable FOXE1 expression to observe the biological effect on colorectal cancer, including cell growth, migration, actin cytoskeleton, and growth of human colorectal xenografts in nude mice. Ectopic expression of FOXE1 could suppress tumor cell growth and migration and affect the organization of the actin cytoskeleton together with suppressing tumorigenicity in vivo. FOXE1 methylation was frequently seen in association with a complete absence of or downregulated gene expression, and FOXE1 plays a suppressive role in the development and progression of colorectal cancer.

5.
J Parasitol ; 110(3): 210-217, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38811020

RESUMO

Alveolar echinococcosis is considered to be one of the most potentially lethal parasitic zoonotic diseases. However, the molecular mechanisms by which Echinococcus multilocularis interacts with hosts are poorly understood, hindering the prevention and treatment of this disease. Due to the great advantages of cell culture systems for molecular research, numerous attempts have been made to establish primary cell cultures for E. multilocularis. In this study we developed a simple, rapid, and economical method that allows E. multilocularis metacestode tissue blocks to generate daughter vesicles without the continuous presence of host feeder cells in a regular medium. We performed anaerobic, hypoxic (1% O2), normoxic, and semi-anaerobic (in sealed tubes) cultures and found that E. multilocularis metacestode tissues can produce daughter vesicles only in the sealed tubes after 4 wk of incubation. The daughter vesicles cultivated in this system were remarkably enlarged under anaerobic conditions after 8 days of culture, whereas vesicles cultured under hypoxic (1% O2) and normoxic conditions showed only a mild increase in volume. Our in vitro cultivated vesicles showed strong viability and could be used to test antiparasitic drugs, isolate primary cells, and infect animals.


Assuntos
Echinococcus multilocularis , Animais , Echinococcus multilocularis/crescimento & desenvolvimento , Equinococose/parasitologia , Camundongos , Anaerobiose , Técnicas de Cultura de Células
6.
Heliyon ; 10(7): e29299, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38623252

RESUMO

Early mutation identification guides patients with colorectal cancer (CRC) toward targeted therapies. In the present study, 414 patients with CRC were enrolled, and amplicon-based targeted next-generation sequencing (NGS) was then performed to detect genomic alterations within the 73 cancer-related genes in the OncoAim panel. The overall mutation rate was 91.5 % (379/414). Gene mutations were detected in 38/73 genes tested. The most frequently mutated genes were TP53 (60.9 %), KRAS (46.6 %), APC (30.4 %), PIK3CA (15.9 %), FBXW7 (8.2 %), SMAD4 (6.8 %), BRAF (6.5 %), and NRAS (3.9 %). Compared with the wild type, TP53 mutations were associated with low microsatellite instability/microsatellite stability (MSI-L/MSS) (P = 0.007), tumor location (P = 0.043), and histological grade (P = 0.0009); KRAS mutations were associated with female gender (P = 0.026), distant metastasis (P = 0.023), TNM stage (P = 0.013), and histological grade (P = 0.004); APC mutations were associated with patients <64 years of age at diagnosis (P = 0.04); PIK3CA mutations were associated with tumor location (P = 4.97e-06) and female gender (P = 0.018); SMAD4 mutations were associated with tumor location (P = 0.033); BRAF mutations were associated with high MSI (MSI-H; P = 6.968e-07), tumor location (P = 1.58e-06), and histological grade (P = 0.04). Mutations in 164 individuals were found to be pathogenic or likely pathogenic. A total of 26 patients harbored MSI-H tumors and they all had at least one detected gene mutation. Mutated genes were enriched in signaling pathways associated with CRC. The present findings have important implications for improving the personalized treatment of patients with CRC in China.

7.
Pediatr Blood Cancer ; 71(6): e30970, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38556751

RESUMO

Langerhans cell histiocytosis (LCH) is a rare hematologic neoplasm characterized by the clonal proliferation of Langerhans-like cells. Colony-stimulating factor 1 receptor (CSF1R) is a membrane-bound receptor that is highly expressed in LCH cells and tumor-associated macrophages. In this study, a soluble form of CSF1R protein (sCSF1R) was identified by plasma proteome profiling, and its role in evaluating LCH prognosis was explored. We prospectively measured plasma sCSF1R levels in 104 LCH patients and 10 healthy children using ELISA. Plasma sCSF1R levels were greater in LCH patients than in healthy controls (p < .001) and significantly differed among the three disease extents, with the highest level in MS RO+ LCH patients (p < .001). Accordingly, immunofluorescence showed the highest level of membrane-bound CSF1R in MS RO+ patients. Furthermore, the plasma sCSF1R concentration at diagnosis could efficiently predict the prognosis of LCH patients treated with standard first-line treatment (AUC = 0.782, p < .001). Notably, dynamic monitoring of sCSF1R levels could predict relapse early in patients receiving BRAF inhibitor treatment. In vitro drug sensitivity data showed that sCSF1R increased resistance to Ara-C in THP-1 cells expressing ectopic BRAF-V600E. Overall, the plasma sCSF1R level at diagnosis and during follow-up is of great clinical importance in pediatric LCH patients.


Assuntos
Histiocitose de Células de Langerhans , Receptor de Fator Estimulador de Colônias de Macrófagos , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos , Humanos , Histiocitose de Células de Langerhans/diagnóstico , Histiocitose de Células de Langerhans/patologia , Histiocitose de Células de Langerhans/sangue , Masculino , Feminino , Criança , Prognóstico , Pré-Escolar , Lactente , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/sangue , Adolescente , Estudos Prospectivos , Seguimentos
8.
Int J Biol Sci ; 20(5): 1947-1964, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481800

RESUMO

Kirsten rat sarcoma viral oncogene homolog (KRAS) is an oncogene implicated in the pathophysiology of many cancers. Increasing evidence shows that KRAS mutation is correlated with poor prognosis in numerous cancers, including colorectal cancer (CRC), breast cancer, and melanoma. KRAS also participates in regulating the CRC microenvironment. However, the direct and indirect therapeutic targets of KRAS in CRC have not been identified; thus, elucidating the mechanisms and interactions between KRAS and the tumor microenvironment (TME) in-depth is paramount. Herein, we present some of the major roles KRAS plays in shaping the heterogeneity of the TME and propose a potential strategy for targeting the downstream components of the KRAS signaling pathway and the TME in CRC.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Microambiente Tumoral/genética , Mutação/genética , Transdução de Sinais/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia
9.
Ann Hematol ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38494553

RESUMO

Minimal residual disease (MRD) based risk stratification criteria for specific genetic subtypes remained unclear in childhood acute lymphoblastic leukemia (ALL). Among 723 children with newly diagnosed ALL treated with the Chinese Children Leukemia Group CCLG-2008 protocol, MRD was assessed at time point 1 (TP1, at the end of induction) and TP2 (before consolidation treatment) and the MRD levels significantly differed in patients with different fusion genes or immunophenotypes (P all < 0.001). Moreover, the prognostic impact of MRD varied by distinct molecular subtypes. We stratified patients in each molecular subtype into two MRD groups based on the results. For patients carrying BCR::ABL1 or KMT2A rearrangements, we classified patients with MRD < 10-2 at both TP1 and TP2 as the low MRD group and the others as the high MRD group. ETV6::RUNX1+ patients with TP1 MRD < 10-3 and TP2 MRD-negative were classified as the low MRD group and the others as the high MRD group. For T-ALL, We defined children with TP1 MRD ≥ 10-3 as the high MRD group and the others as the low MRD group. The 10-year relapse-free survival of low MRD group was significantly better than that of high MRD group. We verified the prognostic impact of the subtype-specific MRD-based stratification in patients treated with the BCH-ALL2003 protocol. In conclusion, the subtype-specific MRD risk stratification may contribute to the precise treatment of childhood ALL.

10.
ACS Sens ; 9(3): 1508-1514, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38387077

RESUMO

In situ and real-time determination of hydroxyl radicals (•OH) in physiological and pathological processes is a great challenge due to their ultrashort lifetime. Herein, an electrochemical method was developed by using dimethyl sulfoxide (DMSO) as a trapping probe for rapid determination of •OH in aqueous solution. When DMSO reacted with •OH, an intermediate product methane sulfinic acid (MSIA) was formed, which can be electrochemically oxidized to methanesulfonic acid (MSA) on the glassy carbon electrode (GCE), resulting in a distinct voltammetric signal that is directly proportional to the concentration of •OH. Other commonly encountered reactive oxygen species (ROS), including hypochlorite anions (ClO-), superoxide anions (O2•-), sulfate radicals (SO4•-), and singlet oxygen (1O2), have showed no interference for •OH determination. Thus, an electrochemical method was developed for the determination of •OH, which exhibits a wide linear range (0.4-5120 µM) and a low limit detection of 0.13 µM (S/N = 3) and was successfully applied for the quantification of •OH in aqueous extracts of cigarette tar (ACT). Alternatively, the same reaction mechanism is also applicable for the determination of DMSO, in which a linear range of 40-320 µM and a detection limit 13.3 µM (S/N = 3) was achieved. The method was used for the evaluation of DMSO content in cell cryopreservation medium. This work demonstrated that DMSO can serve as an electrochemical probe and has valuable application potential in radical study, biological research, and environmental monitoring.


Assuntos
Dimetil Sulfóxido , Radical Hidroxila , Radical Hidroxila/química , Dimetil Sulfóxido/química , Espécies Reativas de Oxigênio , Indicadores e Reagentes , Água
11.
BMC Cancer ; 24(1): 5, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166748

RESUMO

OBJECTIVE: The aim of the study is to identify clinical and dosimetric factors that could predict the risk of radiation-induced hypothyroidism(RIHT) in head and neck cancer(HNC) patients following intensity-modulated radiotherapy(IMRT). METHODS: A total of 103 HNC patients were included in our study. General clinical characteristic and dosimetric data of all recruited patients were analyzed, respectively. The univariate and multivariate logistic regression anlalysis were successively conducted to identify optimal predictors, which aim to construct the nomogram. And the joint prediction was performed. RESULTS: The incidence of patients with HNC was 36.9% (38/103). Among the clinical factors, gender, N stage, chemotherapy, frequency of chemotherapy and surgery involving the thyroid were related to RIHT. Logistic regression analysis showed that thyroid volume, Dmean, VS45, VS50, VS60 and V30,60 were independent predictors of RIHT, which were also incorporated in the nomogram. An AUC of 0.937 (95%CI, 0.888-0.958) also was showed outstanding resolving ability of the nomogram. When the volume of the thyroid was greater than 10.6 cm3, the incidence of RIHT was 14.8%, and when the volume of the thyroid was equal to or smaller than 10.6 cm3, the incidence was 72.5%. The incidence rates of RIHT in the group with VS60≦8.4cm3 and VS60 > 8.4cm3 were 61.4% and 19.3%, respectively. CONCLUSIONS: Thyroid volume and thyroid VS60 are independent predictors of RIHT in patients with HNC. Moreover, more attention should be paid to patients with thyroid volume ≤ 10.6cm3. Thyroid VS60 > 8.4cm3 may be a useful threshold for predicting the development of RIHT. The nomogram conducted by the research may become a potential and valuable tool that could individually predict the risk of RIHT for HNC patients.


Assuntos
Neoplasias de Cabeça e Pescoço , Hipotireoidismo , Humanos , Dosagem Radioterapêutica , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/complicações , Hipotireoidismo/epidemiologia , Hipotireoidismo/etiologia , Fatores de Risco
12.
J Cardiovasc Pharmacol ; 83(5): 474-481, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38113918

RESUMO

ABSTRACT: Studies have examined the therapeutic effect of levosimendan on cardiovascular diseases such as heart failure, perioperative cardiac surgery, and septic shock, but the specific mechanism in mice remains largely unknown. This study aimed to investigate the relaxation mechanism of levosimendan in the thoracic aorta smooth muscle of mice. Levosimendan-induced relaxation of isolated thoracic aortic rings that were precontracted with norepinephrine or KCl was recorded in an endothelium-independent manner. Vasodilatation by levosimendan was not associated with the production of the endothelial relaxation factors nitric oxide and prostaglandins. The voltage-dependent K + channel (K V ) blocker (4-aminopyridine) and selective K Ca blocker (tetraethylammonium) had no effect on thoracic aortas treated with levosimendan, indicating that K V and K Ca channels may not be involved in the levosimendan-induced relaxation mechanism. Although the inwardly rectifying K + channel (K ir ) blocker (barium chloride) and the K ATP channel blocker (glibenclamide) significantly inhibited levosimendan-induced vasodilation in the isolated thoracic aorta, barium chloride had a much stronger inhibitory effect on levosimendan-induced vasodilation than glibenclamide, suggesting that levosimendan-induced vasodilation may be mediated by K ir channels. The vasodilation effect and expression of K ir 2.1 induced by levosimendan were further enhanced by the PKC inhibitor staurosporine. Extracellular calcium influx was inhibited by levosimendan without affecting intracellular Ca 2+ levels in the isolated thoracic aorta. These results suggest that K ir channels play a more important role than K ATP channels in regulating vascular tone in larger arteries and that the activity of the K ir channel is enhanced by the PKC pathway.


Assuntos
Aorta Torácica , Músculo Liso Vascular , Proteína Quinase C , Simendana , Vasodilatação , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Simendana/farmacologia , Masculino , Vasodilatação/efeitos dos fármacos , Proteína Quinase C/metabolismo , Proteína Quinase C/antagonistas & inibidores , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Camundongos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Canais de Potássio Corretores do Fluxo de Internalização/efeitos dos fármacos , Vasodilatadores/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia
13.
Int J Biol Sci ; 19(13): 4291-4310, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705754

RESUMO

Non-small cell lung cancer (NSCLC) is a highly lethal disease worldwide. We found the pseudogene-derived lncRNA PTTG3P is upregulated in NSCLC and associated with larger tumor size, advanced staging, and poor prognosis. This study investigated the oncogenic roles and mechanisms of PTTG3P in NSCLC. We demonstrate that PTTG3P promoted NSCLC cell proliferation, migration, tumorigenesis, and metastasis while inhibiting apoptosis in vitro and in vivo. Mechanistically, PTTG3P formed an RNA-protein complex with ILF3 to maintain MAP2K6 and E2F1 mRNA stability, two oncogenic factors involved in NSCLC progression. RNA-seq revealed MAP2K6 and E2F1 were downregulated upon PTTG3P knockdown. RIP and RNA stability assays showed PTTG3P/ILF3 interaction stabilized MAP2K6 and E2F1 transcripts. Interestingly, E2F1 transcriptionally upregulated PTTG3P by binding its promoter, forming a positive feedback loop. Knockdown of E2F1 or PTTG3P attenuated their mutual regulatory effects on cell growth and migration. Thus, a PTTG3P/ILF3/E2F1 axis enhances oncogene expression to promote NSCLC pathogenesis. Our study reveals PTTG3P exerts oncogenic functions in NSCLC via mRNA stabilization and a feedback loop, highlighting its potential as a prognostic biomarker and therapeutic target.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Retroalimentação , Neoplasias Pulmonares/genética , Transformação Celular Neoplásica , Carcinogênese/genética , Estabilidade de RNA/genética , Proteínas do Fator Nuclear 90/genética , Fator de Transcrição E2F1/genética
14.
Proc Natl Acad Sci U S A ; 120(38): e2306601120, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37695899

RESUMO

Cherenkov radiation occurs only when a charged particle moves with a velocity exceeding the phase velocity of light in that matter. This radiation mechanism creates directional light emission at a wide range of frequencies and could facilitate the development of on-chip light sources except for the hard-to-satisfy requirement for high-energy particles. Creating Cherenkov radiation from low-energy electrons that has no momentum mismatch with light in free space is still a long-standing challenge. Here, we report a mechanism to overcome this challenge by exploiting a combined effect of interfacial Cherenkov radiation and umklapp scattering, namely the constructive interference of light emission from sequential particle-interface interactions with specially designed (umklapp) momentum-shifts. We find that this combined effect is able to create the interfacial Cherenkov radiation from ultralow-energy electrons, with kinetic energies down to the electron-volt scale. Due to the umklapp scattering for the excited high-momentum Bloch modes, the resulting interfacial Cherenkov radiation is uniquely featured with spatially separated apexes for its wave cone and group cone.

15.
Phys Rev Lett ; 131(11): 113002, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774266

RESUMO

When a charged particle penetrates through an optical interface, photon emissions emerge-a phenomenon known as transition radiation. Being paramount to fundamental physics, transition radiation has enabled many applications from high-energy particle identification to novel light sources. A rule of thumb in transition radiation is that the radiation intensity generally decreases with the decrease of particle velocity v; as a result, low-energy particles are not favored in practice. Here, we find that there exist situations where transition radiation from particles with extremely low velocities (e.g., v/c<10^{-3}) exhibits comparable intensity as that from high-energy particles (e.g., v/c=0.999), where c is the light speed in free space. The comparable radiation intensity implies an extremely high photon extraction efficiency from low-energy particles, up to 8 orders of magnitude larger than that from high-energy particles. This exotic phenomenon of low-velocity-favored transition radiation originates from the interference of the excited Ferrell-Berreman modes in an ultrathin epsilon-near-zero slab. Our findings may provide a promising route toward the design of integrated light sources based on low-energy electrons and specialized detectors for beyond-standard-model particles.

16.
Phytochemistry ; 215: 113870, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37734511

RESUMO

Seven previously undescribed lanostane triterpenoids, ganoderic acid M1 (1), M2 (2), M3 (3), M4 (4), M5 (5), M6 (6), and M7 (7), together with eight known compounds, were isolated from mycelia of the basidiomycete Ganoderma sinense (Ganodermataceae). The structures of all compounds were elucidated by spectroscopic analysis. The possible biosynthetic pathway of these fifteen triterpenoids was proposed. Some of the compounds were evaluated for their anti-inflammatory activity by measuring the production of nitric oxide (NO), TNF-α, and IL-6 in RAW264.7 macrophage cells induced by lipopolysaccharide. Lanosta-7,9(11),24-trien-3ß,15α,22ß-triacetoxy-26-oic acid (14) exhibited the strongest inhibition of NO production with an IC50 of 0.6 ± 0.1 µM and completely inhibited the secretion of TNF-α and IL-6 at 10 µM. The structure-activity relationship of the anti-inflammatory activity is discussed.


Assuntos
Ganoderma , Triterpenos , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Carpóforos/química , Triterpenos/química , Ganoderma/química , Esteroides/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Estrutura Molecular
17.
Stat Med ; 42(25): 4632-4643, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37607718

RESUMO

In this article, we present a flexible model for microbiome count data. We consider a quasi-likelihood framework, in which we do not make any assumptions on the distribution of the microbiome count except that its variance is an unknown but smooth function of the mean. By comparing our model to the negative binomial generalized linear model (GLM) and Poisson GLM in simulation studies, we show that our flexible quasi-likelihood method yields valid inferential results. Using a real microbiome study, we demonstrate the utility of our method by examining the relationship between adenomas and microbiota. We also provide an R package "fql" for the application of our method.


Assuntos
Microbiota , Modelos Estatísticos , Humanos , Funções Verossimilhança , Simulação por Computador , Distribuição de Poisson
18.
Int J Lab Hematol ; 45(5): 717-725, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37194559

RESUMO

INTRODUCTION: Relapse remained the major obstacle to improving the prognosis of children with acute lymphoblastic leukemia (ALL). This study aimed to investigate the changing patterns of Ig/TCR gene rearrangements between diagnosis and relapse and the clinical relevance and to explore the mechanism of leukemic relapse. METHODS: Clonal Ig/TCR gene rearrangements were screened by multiplex PCR amplification in 85 paired diagnostic and relapse bone marrow (BM) samples from children with ALL. The new rearrangements presented at relapse were quantitatively assessed by the RQ-PCR approach targeting the patient-specific junctional region sequence in 19 diagnostic samples. The relapse clones were further back-traced to diagnostic and follow-up BM samples from 12 patients. RESULTS: Comparison of Ig/TCR gene rearrangements between diagnosis and relapse showed that 40 (57.1%) B-ALL and 5 (33.3%) T-ALL patients exhibited a change from diagnosis to relapse, and 25 (35.7%) B-ALL patients acquired new rearrangements at relapse. The new relapse rearrangements were present in 15 of the 19 (78.9%) diagnostic samples as shown by RQ-PCR, with a median level of 5.26 × 10-2 . The levels of minor rearrangements correlated with B immunophenotype, WBC counts, age at diagnosis, and recurrence time. Furthermore, back-tracing rearrangements in 12 patients identified three patterns of relapse clone dynamics, which suggested the recurrence mechanisms not only through clonal selection of pre-existing subclones but also through an ongoing clonal evolution during remission and relapse. CONCLUSION: Backtracking Ig/TCR gene rearrangements in relapse clones of pediatric ALL revealed complex patterns of clonal selection and evolution for leukemic relapse.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Recidiva , Doença Crônica , Células Clonais , Reação em Cadeia da Polimerase Multiplex , Rearranjo Gênico , Receptores de Antígenos de Linfócitos T/genética
19.
Eur Urol Focus ; 9(6): 983-991, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37105783

RESUMO

BACKGROUND: Molecular signatures in prostate cancer (PCa) tissue can provide useful prognostic information to improve the understanding of a patient's risk of harbouring aggressive disease. OBJECTIVE: To develop and validate a gene signature that adds independent prognostic information to clinical parameters for better treatment decisions and patient management. DESIGN, SETTING, AND PARTICIPANTS: Expression of 14 genes was evaluated in radical prostatectomy (RP) tissue from an Irish cohort of PCa patients (n = 426). A six-gene molecular risk score (MRS) was identified with strong prognostic performance to predict adverse pathology (AP) at RP or biochemical recurrence (BCR). The MRS was combined with the Cancer of the Prostate Risk Assessment (CAPRA) score, to create a molecular and clinical risk score (MCRS), and validated in a Swedish cohort (n = 203). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary AP outcome was assessed by the likelihood ratio statistics and area under the receiver operating characteristics curves (AUC) from logistic regression models. The secondary time to BCR outcome was assessed by likelihood ratio statistics and C-indexes from Cox proportional hazard regression models. RESULTS AND LIMITATIONS: The six-gene signature was significantly (p < 0.0001) prognostic and added significant prognostic value to clinicopathological features for AP and BCR outcomes. For both outcomes, both the MRS and the MCRS increased the AUC/C-index when added to European Association of Urology (EAU) and CAPRA scores. Limitations include the retrospective nature of this study. CONCLUSIONS: The six-gene signature has strong performance for the prediction of AP and BCR in an independent clinical validation study. MCRS improves prognostic evaluation and can optimise patient management after RP. PATIENT SUMMARY: We found that the expression panel of six genes can help predict whether a patient is likely to have a disease recurrence after radical prostatectomy surgery.


Assuntos
Recidiva Local de Neoplasia , Neoplasias da Próstata , Masculino , Humanos , Estudos Retrospectivos , Medição de Risco/métodos , Recidiva Local de Neoplasia/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Próstata/patologia
20.
Int J Med Mushrooms ; 25(4): 65-73, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37075085

RESUMO

Volatile oil extracted from fermentation broth of Ganoderma lingzhi by hydrodistillation was analyzed based on gas chromatography-mass spectrometry (GC-MS). Its antitumor activity was tested on K562, SW620, A549, HepG2 cells in vitro. In addition, the antioxidant activity of the oil was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. In total, 16 constituents were identified accounting for about 99.99% of the total volatile oil in the fermentation broth of G. lingzhi. Among these components, 1-propanol (33.33%), phenylacetaldehyde (24.24%), 2-hexyl-1-decanol (12.12%) were found to be the major constituents. The antitumor results showed that the IC50 of the inhibition to the proliferation of K562, SW620, A549, HepG2 cells were 32.2, 78.9, 96.4, 99.0 µg/mL, respectively. And the oil could inhibit the proliferation of K562 cells by apoptosis induction and cell cycle arrest at S phase. Moreover, the oil exhibited radical scavenging activity (IC50 = 0.1469 mg/mL) in DPPH assay.


Assuntos
Ganoderma , Óleos Voláteis , Antioxidantes/farmacologia , Antioxidantes/química , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Fermentação
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