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1.
Zookeys ; 1177: 23-40, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692325

RESUMO

The first exploratory study was conducted on the compound eye morphology and spectral characteristics of Agasicleshygrophila (Selman & Vogt, 1971) to clarify its eye structure and its spectral sensitivity. Scanning electron microscopy, paraffin sectioning, and transmission electron microscopy revealed that A.hygrophila has apposition compound eyes with both eucones and open rhabdom. The micro-computed tomography (CT) results after 3D reconstruction demonstrated the precise position of the compound eyes in the insect's head and suggested that the visual range was mainly concentrated in the front and on both sides of the head. The electroretinogram (ERG) experiment showed that red, yellow, green, blue, and ultraviolet light could stimulate the compound eyes of A.hygrophila to produce electrical signals. The behavioural experiment results showed that both males and females had the strongest phototaxis to yellow light and positive phototaxis to red, green, and blue light but negative phototaxis to UV light. This study of the compound eyes of A.hygrophila will be helpful for decoding its visual mechanism in future studies.

2.
World J Surg Oncol ; 21(1): 125, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024930

RESUMO

BACKGROUND: The randomized trials which include ACOSOG Z0011 and IBCSG 23-01 had found that the survival rates were not different in patients with cT1/2N0 and 1-2 sentinel lymph node (SLN)-positive, macro/micrometastases who underwent breast-conserving therapy, and micrometastases who underwent total mastectomy (TM), when axillary lymph node dissection (ALND) was omitted. However, for patients with cT1/2N0 and 1-2 SLN macrometastases who underwent TM; there was still insufficient evidence from clinical studies to support whether ALND can be exempted. This study aimed to investigate the risk factors of non-sentinel lymph node (nSLN) metastasis in breast cancer patients with 1-2 SLN macrometastases undergoing TM. METHODS: The clinicopathological data of 1491 breast cancer patients who underwent TM and SLNB from January 2017 to February 2022 were retrospectively analyzed. Univariate and multivariate analyses were performed to analyze the risk factors for nSLN metastasis. RESULTS: A total of 273 patients with 1-2 SLN macrometastases who underwent TM were enrolled. Postoperative pathological data showed that 35.2% patients had nSLN metastasis. The results of multivariate analysis indicated that tumor size (TS) (P = 0.002; OR: 1.051; 95% CI: 1.019-1.084) and ratio of SLN macrometastases (P = 0.0001; OR: 12.597: 95% CI: 4.302-36.890) were the independent risk factors for nSLN metastasis in breast cancer patients with 1-2 SLN macrometastases that underwent TM. The ROC curve analysis suggested that when TS ≤22 mm and ratio of SLN macrometastases ≤0.33, the incidence of nSLN metastasis could be reduced to 17.1%. CONCLUSIONS: The breast cancer patients with cT1/2N0 stage, undergoing TM and 1-2 SLN macrometastases, when the TS ≤22 mm and macrometastatic SLN does not exceed 1/3 of the total number of detected SLN, the incidence of nSLN metastasis is significantly reduced, but whether ALND can be exempted needs further exploration.


Assuntos
Neoplasias da Mama , Linfonodo Sentinela , Humanos , Feminino , Neoplasias da Mama/patologia , Biópsia de Linfonodo Sentinela/métodos , Metástase Linfática/patologia , Estudos de Casos e Controles , Mastectomia Simples , Estudos Retrospectivos , Micrometástase de Neoplasia/patologia , Mastectomia , Axila/patologia , Linfonodo Sentinela/cirurgia , Linfonodo Sentinela/patologia , Excisão de Linfonodo/métodos , Fatores de Risco , Linfonodos/cirurgia , Linfonodos/patologia
3.
Medicine (Baltimore) ; 100(2): e23834, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33466130

RESUMO

BACKGROUND: Polymorphism in miR-27a rs895819 has been associated with breast cancer (BC) risk, but studies have reported inconsistent results. This meta-analysis investigated the possible association between miR-27a rs895819 polymorphism and BC risk. METHODS: PubMed, EMBASE, Google Scholar, and the Chinese National Knowledge Infrastructure (CNKI) databases were systematically searched to identify relevant studies in English and Chinese. Meta-analyses were performed to examine the association between miR-27a rs895819 and BC susceptibility. RESULTS: A total of 16 case-control studies involving 6118 cases and 7042 controls were included. Analysis using five genetic models suggested no significant association between miR-27a rs895819 polymorphism and BC risk in the total population, or specifically in Asian or Chinese subpopulations. In the Caucasian subpopulation, however, the G-allele and AG genotype at rs895819 were significantly associated with decreased BC risk according to the allelic model (OR 0.90, 95% CI 0.84-0.97, P = .004) and heterozygous model (OR 0.89, 95% CI 0.81-089, P = .02), while the wild-type AA genotype was significantly associated with increased BC risk according to the dominant model (OR 1.13, 95% CI 1.03-1.24, P = .007). CONCLUSION: These results indicate that among Caucasians, the wild-type AA genotype at rs895819 may confer increased susceptibility to BC, while the G-allele and AG genotype may be protective factors. These conclusions should be verified in large, well-designed studies.


Assuntos
Neoplasias da Mama/genética , MicroRNAs/genética , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco , População Branca/genética
4.
Insect Sci ; 27(4): 815-825, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31250982

RESUMO

As solitary nymphal parasitoids of Paratrioza sinica, the ectoparasitoid Tamarixia lyciumi and the endoparasitoid Psyllaephagus arenarius act as effective biocontrol agents. Thus, it is necessary to facilitate mass productions of both species. Despite showing an excellent parasitic ability, Ps. arenarius is often trapped fatally inside 5th-instar nymphs of Pa. sinica due to strong host immunity. To improve the emergence rate of Ps. arenarius, we evaluated whether Ps. arenarius could utilize T. lyciumi venom via multiparasitism, so the parasitism characteristics of both species were examined between separate-existence (monoparasitism only) and co-existence (mono- and multiparasitism) systems. Further, the parasitism characteristics of Ps. arenarius on venom-injected hosts with/without T. lyciumi eggs were tested to further identify the facilitator. The results showed the parasitism rate of T. lyciumi was increased while that of Ps. arenarius did not change from separate-existence to co-existence systems. The intrinsic performances of two species in monoparasitism did not differ between separate- and co-existence systems. From monoparasitism (separate-existence) to multiparasitism (co-existence), no differences were detected in the intrinsic performances of T. lyciumi, but those of Ps. arenarius were greatly improved. After T. lyciumi venom injection, the parasitism characteristics of Ps. arenarius did not differ between venom-injected hosts with T. lyciumi eggs and those without, further indicating Ps. arenarius benefited from the venom of T. lyciumi females rather than T. lyciumi egg/larval secretions. Instead of negative effects, multiparasitism with ectoparasitoids improves endoparasitoids due to ectoparasitic venom. The study increases host resource utilization and provides creative ways for mass production of endoparasitoids.


Assuntos
Hemípteros/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Venenos de Vespas/metabolismo , Vespas/fisiologia , Animais , Feminino , Hemípteros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Ninfa/crescimento & desenvolvimento , Ninfa/parasitologia , Vespas/crescimento & desenvolvimento
5.
Neurochem Res ; 37(2): 298-306, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21952928

RESUMO

Bilobalide (BB), a sesquiterpenoid extract of Ginkgo biloba leaves, has been demonstrated to have neuroprotective effects. The neuroprotective mechanisms were suggested to be associated with modulation of intracellular signaling cascades such as the phosphatidyl inositol 3-kinase (PI3K) pathway. Since some members of intracellular signalling pathways such as PI3K have been demonstrated to be involved in amyloid precursor protein (APP) processing, the present study investigated whether BB has an influence on the ß-secretase-mediated APP cleavage via PI3K-dependent pathway. Using HT22 cells and SAMP8 mice (a senescence-accelerated strain of mice), this study showed that BB treatment reduced generation of two ß-secretase cleavage products of APP, the amyloid ß-peptide (Aß) and soluble APPß (sAPPß), via PI3K-dependent pathway. Additionally, glycogen synthase kinase 3ß (GSK3ß) signaling might be involved in BB-induced Aß reduction as a downstream target of the activated PI3K pathway. BB showed no significant effects on ß-site APP cleaving enzyme 1 (BACE-1) or γ-secretase but inhibited the ß-secretase activity of another protease cathepsin B, suggesting that BB-induced Aß reduction was probably mediated through modulation of cathepsin B rather than BACE-1. Similarly, inhibition of GSK3ß did not affect BACE-1 activity but decreased cathepsin B activity, suggesting that the PI3K-GSK3ß pathway was probably involved in BB-induced Aß reduction. Increasing evidence suggests that decreasing Aß production in the brain via modulation of APP metabolism should be beneficial for the prevention and treatment of Alzheimer's disease (AD). BB may offer such an approach to combat AD.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Ciclopentanos/farmacologia , Furanos/farmacologia , Ginkgolídeos/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Animais , Linhagem Celular , Glicogênio Sintase Quinase 3 beta , Camundongos , Transdução de Sinais
6.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 46(3): 172-6, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21575441

RESUMO

OBJECTIVE: To evaluate the types and compositions of oxide films formed during porcelain-fused-to-metal (PFM) firing on three kinds of dental casting alloys, and to investigate the corrosion property of these alloys in Dulbecco's modification of Eagle's medium (DMEM) cell culture fluid, before and after PFM firing. METHODS: Specimens of three dental casting alloys (Ni-Cr, Co-Cr and Ni-Ti) before and after PFM firing were prepared, and were immersed in DMEM cell culture fluid. After 30 days, the type and concentration of released metal ions were measured using inductively coupled plasma atomic emission spectroscopy (ICP-AES). X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were used for analysis of oxide film on the alloys. One way-ANOVA was adopted in data analysis. RESULTS: The total amount of metal ions released from the three dental alloys was found to be highest in Ni-Cr alloy [(2.829 ± 0.694) mg/L], followed by Co-Cr [(2.120 ± 0.418) mg/L] and Ni-Ti alloy [(1.211 ± 0.101) mg/L]. The amount of Ni ions released from Ni-Cr alloys [(1.531 ± 0.392) mg/L] was higher than that from Ni-Ti alloys [(0.830 ± 0.052) mg/L]. The amount of Cr, Mo ions released from Co-Cr alloy [Cr: (0.048 ± 0.011) mg/L, Mo: (1.562 ± 0.333) mg/L] was higher than that from Ni-Cr alloy [Cr: (0.034 ± 0.002) mg/L, Mo: (1.264 ± 0.302) mg/L] and Ni-Ti alloy [Cr: (0.013 ± 0.006) mg/L, Mo: (0.151 ± 0.026) mg/L] (P < 0.05). After PFM firing, the total amount of metal irons released from the three dental alloys decreased [Ni-Cr: (0.861 ± 0.054) mg/L, Co-Cr: (0.695 ± 0.327) mg/L, Ni-Ti: (0.892 ± 0.115) mg/L] (P < 0.05). In addition, XPS showed increase of Cr(2)O(3) and Mo-Ni oxide on the surface of all the alloys after PFM firing. CONCLUSIONS: The amount of ions released from Ni-Cr alloy was the highest among the three dental casting alloys, this means Ni-Cr alloy is prone to corrode. The PFM firing process changed the alloys' surface composition. Increased Ni, Cr and Mo were found in oxide film, and the increase in Cr(2)O(3) can improve the corrosion-resistance of alloys.


Assuntos
Ligas Dentárias/química , Técnica de Fundição Odontológica , Porcelana Dentária/química , Óxidos , Ligas de Cromo/química , Corrosão , Análise do Estresse Dentário , Íons , Teste de Materiais , Microscopia Eletroquímica de Varredura , Molibdênio/química , Níquel/química , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Titânio/química
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