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1.
Nano Lett ; 24(1): 156-164, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38147652

RESUMO

Graphene nanoribbons (GNRs), quasi one-dimensional (1D) narrow strips of graphene, have shown promise for high-performance nanoelectronics due to their exceptionally high carrier mobility and structurally tunable bandgaps. However, producing chirality-uniform GNRs on insulating substrates remains a big challenge. Here, we report the successful growth of bilayer GNRs with predominantly armchair chirality and ultranarrow widths (<5 nm) on insulating hexagonal boron nitride (h-BN) substrates using chemical vapor deposition (CVD). The growth of GNRs is catalyzed by transition metal nanoparticles, including Fe, Co, and Ni, through a unique tip-growth mechanism. Notably, GNRs catalyzed by Ni exhibit a high purity (97.3%) of armchair chirality. Electron transport measurements indicate that the ultrathin bilayer armchair GNRs exhibit quasi-metallic behavior. This quasi-metallicity is further supported by density functional theory (DFT) calculations, which reveal a significantly reduced bandgap in bilayer armchair GNRs. The chirality-specific GNRs reported here offer promising advancements for the application of graphene in nanoelectronics.

2.
Ecotoxicol Environ Saf ; 278: 116428, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38723384

RESUMO

BACKGROUND: Phthalates (PAEs) are endocrine-disrupting chemicals ubiquitously found in the environment. This study aimed to examine the association between exposure of PAEs and subfecundity in preconception couples. METHODS: This is a nested case-control study based on preconception cohort. Preconception couples with intention to conceive were enrolled and followed up until a clinically confirmed pregnancy or 12 menstrual cycles of preparation for conception. A total of 107 couples with subfecundity- time to pregnancy (TTP) more than 12 menstrual cycles, and 144 couples ≤12 cycles were included in the analysis. The levels of PAE metabolites in one spot urine samples were detected and compared between the groups. The weighted quantile sum (WQS) regression model and Bayesian kernel machine regression (BKMR) model were used to examine the joint effects of couples' exposure to PAEs on subfecundity. RESULTS: Using the multivariate binary logistic regression model, compared to the lowest quartile of urinary ∑PAEs concentration group, both preconception females (aOR=2.42, 95% CI: 1.10-5.30, p=0.027) and males (aOR=2.99, 95% CI: 1.36-6.58, p=0.006) in the highest quartile group had an increased risk of subfecundity, and a dose-response relationship was observed between PAEs and the risk of subfecundity. The WQS analyses found that co-exposure to PAE mixture was a risk factor for subfecundity in preconception female (aOR=1.76, 95% CI: 1.38-2.26, p<0.001), male (aOR=1.58, 95% CI: 1.20-2.08, p=0.001), and couple (aOR=2.39, 95% CI: 1.61-3.52, p<0.001). The BKMR model found a positive combined effect of mixed exposure to PAEs on the risk of subfecundity. CONCLUSIONS: PAEs increase the risk of subfecundity in preconception couples. Our research reinforced the need of monitoring PAE exposure for the purpose of improving human reproductive health.


Assuntos
Disruptores Endócrinos , Exposição Ambiental , Poluentes Ambientais , Ácidos Ftálicos , Humanos , Ácidos Ftálicos/urina , Estudos de Casos e Controles , Feminino , Masculino , Adulto , Disruptores Endócrinos/urina , Poluentes Ambientais/urina , Exposição Ambiental/estatística & dados numéricos , Exposição Ambiental/análise , Gravidez , Infertilidade/induzido quimicamente , Teorema de Bayes , Tempo para Engravidar/efeitos dos fármacos
3.
Brain Behav Immun ; 113: 328-339, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37543246

RESUMO

Chronic morphine exposure causes the development of addictive behaviors, accompanied by an increase in neuroinflammation in the central nervous system. While previous researches have shown that astrocytes contribute to brain diseases, the role of astrocyte in morphine addiction through induced neuroinflammation remain unexplored. Here we show that morphine-induced inflammation requires the crosstalk among neuron, astrocyte, and microglia. Specifically, astrocytes respond to morphine-induced neuronal activation by increasing glycolytic metabolism. The dysregulation of glycolysis leads to an increased in the generation of mitochondrial reactive oxygen species and causes excessive mitochondrial fragmentation in astrocytes. These fragmented, dysfunctional mitochondria are consequently released into extracellular environment, leading to activation of microglia and release of inflammatory cytokines. We also found that blocking the nicotinamide adenine dinucleotide salvage pathway with FK866 could inhibit astrocytic glycolysis and restore the mitochondrial homeostasis and effectively attenuate neuroinflammatory responses. Importantly, FK866 reversed morphine-induced addictive behaviors in mice. In summary, our findings illustrate an essential role of astrocytic immunometabolism in morphine induced neural and behavioral plasticity, providing a novel insight into the interactions between neurons, astrocytes, and microglia in the brain affected by chronic morphine exposure.


Assuntos
Dependência de Morfina , Camundongos , Animais , Dependência de Morfina/metabolismo , Astrócitos/metabolismo , Doenças Neuroinflamatórias , Morfina/farmacologia , Morfina/metabolismo , Microglia/metabolismo , Mitocôndrias
4.
Retina ; 43(8): 1386-1392, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37130433

RESUMO

PURPOSE: To determine the effect of different durations of topical anesthesia on intravitreal injection (IVI) pain. METHODS: This was a double-blinded, randomized, comparative study . Three hundred and twelve sequential eyes undergoing IVI were randomized to one of six groups according to the duration of topical anesthesia (from 1 to 30 minutes, one group for every 5-minute range, Groups 1-6). Topical anesthesia before IVI was standardized. Patients graded their pain using the visual analog scale and the Wong-Baker FACES scale at 15 minutes after the procedure. RESULTS: The pain scores among the six groups were significantly different for the visual analog scale ( P = 0.013) and Wong-Baker FACES scale ( P = 0.024). The mean pain scores for Group 4 were 1.97 ± 1.04 (visual analog scale) and 2.02 ± 1.08 (Wong-Baker FACES scale) and were significantly lower than those of Group 1, 2, 5, or 6. CONCLUSION: The duration of topical anesthesia significantly correlated with IVI pain. Preoperative 0.5% proparacaine hydrochloride drops were most effective in relieving IVI pain 11 to 20 minutes after topical administration.


Assuntos
Anestesia Local , Dor , Humanos , Injeções Intravítreas , Dor/tratamento farmacológico , Anestesia Local/métodos , Anestésicos Locais , Administração Tópica
5.
Int J Mol Sci ; 24(14)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37511553

RESUMO

As a biological macromolecule, the superantigen staphylococcal enterotoxin C2 (SEC2) is one of the most potent known T-cell activators, and it induces massive cytotoxic granule production. With this property, SEC2 and its mutants are widely regarded as immunomodulating agents for cancer therapy. In a previous study, we constructed an MHC-II-independent mutant of SEC2, named ST-4, which exhibits enhanced immunocyte stimulation and antitumor activity. However, tumor cells have different degrees of sensitivity to SEC2/ST-4. The mechanisms of immune resistance to SEs in cancer cells have not been investigated. Herein, we show that ST-4 could activate more powerful human lymphocyte granule-based cytotoxicity than SEC2. The results of RNA-seq and atomic force microscopy (AFM) analysis showed that, compared with SKOV3 cells, the softer ES-2 cells could escape from SEC2/ST-4-induced cytotoxic T-cell-mediated apoptosis by regulating cell softness through the CDC42/MLC2 pathway. Conversely, after enhancing the stiffness of cancer cells by a nonmuscle myosin-II-specific inhibitor, SEC2/ST-4 exhibited a significant antitumor effect against ES-2 cells by promoting perforin-dependent apoptosis and the S-phase arrest. Taken together, these data suggest that cell stiffness could be a key factor of resistance to SEs in ovarian cancer, and our findings may provide new insight for SE-based tumor immunotherapy.


Assuntos
Antineoplásicos , Enterotoxinas , Humanos , Enterotoxinas/farmacologia , Enterotoxinas/metabolismo , Superantígenos/farmacologia , Antineoplásicos/farmacologia , Linfócitos T , Ativação Linfocitária
6.
Ann Surg Oncol ; 29(5): 3067-3068, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34994910

RESUMO

OBJECTIVE: The aim of this article was to introduce a fascial space priority approach for laparoscopic pelvic exenteration (PE) with bladder-sparing for men with locally advanced rectal cancer. METHODS: We present a video of bladder-sparing laparoscopic PE with fascial space priority approach in a 70-year old man. The systematic de-arterialization of the prostate on the basis of complete separation of the avascular lateral pelvic spaces is introduced in detail. RESULTS: The operation time was 360 min and the estimated intraoperative blood loss was 50 mL. The postoperative course was uneventful and the patient was discharged on postoperative day 14. Histopathological examination showed all margins to be tumor-free. CONCLUSIONS: Bladder-sparing laparoscopic PE using a fascial space priority approach is a feasible and safe procedure that can be performed in well-selected patients following neoadjuvant chemoradiotherapy. Extensive multivisceral resection is possible without a permanent stoma.


Assuntos
Laparoscopia , Exenteração Pélvica , Neoplasias Retais , Idoso , Humanos , Laparoscopia/métodos , Masculino , Exenteração Pélvica/métodos , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Reto/cirurgia , Bexiga Urinária/patologia , Bexiga Urinária/cirurgia
7.
J Natl Compr Canc Netw ; 20(9): 1013-1021.e3, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36075387

RESUMO

BACKGROUND: Optimal analgesic maintenance for severe cancer pain is unknown. This study evaluated the efficacy and safety of intravenous patient-controlled analgesia (IPCA) with continuous infusion plus rescue dose or bolus-only dose versus conventional oral extended-release morphine as a background dose with normal-release morphine as a rescue dose to maintain analgesia in patients with severe cancer pain after successful opioid titration. METHODS: Patients with persistent severe cancer pain (≥7 at rest on the 11-point numeric rating scale [NRS]) were randomly assigned to 1 of 3 treatment arms: (A1) IPCA hydromorphone with bolus-only dose where dosage was 10% to 20% of the total equianalgesic over the previous 24 hours (TEOP24H) administered as needed, (A2) IPCA hydromorphone with continuous infusion where dose per hour was the TEOP24H divided by 24 and bolus dosage for breakthrough pain was 10% to 20% of the TEOP24H, and (B) oral extended-release morphine based on TEOP24H/2 × 75% (because of incomplete cross-tolerance) every 12 hours plus normal-release morphine based on TEOP24H × 10% to 20% for breakthrough pain. After randomization, patients underwent IPCA hydromorphone titration for 24 hours to achieve pain control before beginning their assigned treatment. The primary endpoint was NRS over days 1 to 3. RESULTS: A total of 95 patients from 9 oncology study sites underwent randomization: 30 into arm A1, 32 into arm A2, and 33 into arm B. Arm B produced a significantly higher NRS over days 1 to 3 compared with arm A1 or A2 (P<.001). Daily NRS from day 1 to day 6 and patient satisfaction scores on day 3 and day 6 were worse in arm B. Median equivalent-morphine consumption increase was significantly lower in A1 (P=.024) among the 3 arms. No severe adverse event occurred in any arm. CONCLUSIONS: Compared with oral morphine maintenance, IPCA hydromorphone for analgesia maintenance improves control of severe cancer pain after successful titration. Furthermore, IPCA hydromorphone without continuous infusion may consume less opioid.


Assuntos
Dor Irruptiva , Dor do Câncer , Neoplasias , Analgesia Controlada pelo Paciente , Analgésicos Opioides , Dor Irruptiva/tratamento farmacológico , Dor do Câncer/tratamento farmacológico , Dor do Câncer/etiologia , Humanos , Hidromorfona/efeitos adversos , Morfina/efeitos adversos , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Medição da Dor
8.
Surg Endosc ; 36(8): 6331-6335, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35411456

RESUMO

BACKGROUND: Total pelvic exenteration (TPE) with intent to achieve a pathological R0 resection is now considered as the only chance of a long-term survival for locally advanced rectal cancer (LARC) invading into adjacent organs. Lately, laparoscopic total pelvic exenteration (LTPE) is performed and achieved in several specialized centers and showed a promising application prospect. Although this is universally realized by surgeons, there are only few specialized centers to perform this complex surgery, due to concerns about the high morbidity and mortality. The techniques associated need to be disclosed and facilitated. OBJECTIVE: The aim of this article is to introduce a fascial space priority approach for laparoscopic TPE step by step (with video). METHODS: We describe here a fascial space priority approach for LTPE in highly selected patients with locally advanced rectal cancer. The main principle of this approach is that all of the pelvic organs are considered as a whole, the non-vascular spaces surrounding it are separated in the first place, the vascular pedicle and nerve pedicle of pelvic organs can be isolated and then transected precisely. Meanwhile, the associated key landmarks of this approach are disclosed (see the video). RESULTS: The ureterohypogastric nerve fascia (UHGNF) and the vesicohypogastric fascia (VHGF) are two vital embryological planes on the lateral compartment of pelvis. The spaces on either side of them together with the retrorectal space, the space of Retzius, are all non-vascular spaces, and dissection of these spaces in LTPE surgery can be achieved simply and practicably. The ureter, the umbilical artery, the arcus tendinous fasciae pelvis (ATFP), piriformis and the puboprostatic ligament (PPL) are all important landmarks during surgery. Step-by-step illustration with precise anatomical landmarks in the present video may lead to less intraoperative blood loss and complications. CONCLUSIONS: LTPE with fascial space priority approach might be a standard surgical procedure for total pelvic exenteration with clear anatomy and reduced blood loss.


Assuntos
Laparoscopia , Exenteração Pélvica , Neoplasias Retais , Humanos , Laparoscopia/métodos , Exenteração Pélvica/métodos , Pelve/inervação , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Reto/cirurgia
9.
Microb Ecol ; 81(2): 523-534, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32968841

RESUMO

Maintaining an adaptive seasonality is a basic ecological requisite for cold-blooded organism insects which usually harbor various symbionts. However, how coexisting symbionts coordinate in insects during seasonal progress is still unknown. The whitefly Bemisia tabaci in China harbors the obligate symbiont Portiera that infects each individual, as well as various facultative symbionts. In this study, we investigated whitefly populations in cucumber and cotton fields from May to December 2019, aiming to reveal the fluctuations of symbiont infection frequencies, symbiont coordination in multiple infected individuals, and host plants effects on symbiont infections. The results indicated that the facultative symbionts Hamiltonella (H), Rickettsia (R), and Cardinium (C) exist in field whiteflies, with single (H) and double (HC and HR) infections occurring frequently. Infection frequencies of Hamiltonella (always 100%) and Cardinium (29.50-34.38%) remained steady during seasonal progression. Rickettsia infection frequency in the cucumber whitefly population decreased from 64.47% in summer to 35.29% in winter. Significantly lower Rickettsia infection frequency (15.55%) was identified in cotton whitefly populations and was not subject to seasonal fluctuation. Nevertheless, Rickettsia had a significantly quantitative advantage in the symbiont community of whitefly individuals and populations from both cucumber and cotton field all through the seasons. Moreover, higher Portiera and Hamiltonella densities were found in HC and HR whitefly than in H whitefly, suggesting these symbionts may contribute to producing nutrients for their symbiont partners. These results provide ample cues to further explore the interactions between coexisting symbionts, the coevolutionary relationship between symbionts and host symbiont-induced effects on host plant use.


Assuntos
Hemípteros/microbiologia , Microbiota , Rickettsia/isolamento & purificação , Simbiose , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , China , Cucumis sativus/parasitologia , Gossypium/parasitologia , Interações Microbianas , Rickettsia/classificação , Rickettsia/genética , Estações do Ano
10.
Environ Res ; 193: 110553, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33271145

RESUMO

Pyridine is a common heterocycle found in industrial wastewaters. Its biodegradation begins with a mono-oxygenation reaction, and bioaugmentation with bacteria able to carry out this mono-oxygenation is one strategy to improve pyridine removal and mineralization. Although bioaugmentation has been used to enhance the biodegradation of recalcitrant organic compounds, the specific role played by the bioaugmented bacteria usually has not been addressed. We acclimated activated-sludge biomass for pyridine biodegradation and then isolated a strain -- Comamonas testosteroni -- based on its ability to biodegrade and grow on pyridine alone. Pyridine was removed faster by C. testosteroni, compared to pyridine-acclimated biomass, but pyridine mineralization was slower. Pyridine biodegradation and mineralization rates were accelerated when C. testosteroni was bioaugmented into the acclimated biomass, which increased the amount of C. testosteroni, but otherwise had minimal effects on the microbial community. The key role of C. testosteroni was to accelerate the first step of pyridine biodegradation, mono-oxygenation to 2-hydroxylpyridine (2HP), and the acclimated biomass was better able to complete downstream reactions leading to mineralization. Thus, bioaugmentation increased the rates of pyridine mono-oxygenation and subsequent mineralization through the synergistic roles of C. testosteroni and the main community in the acclimated biomass.


Assuntos
Comamonas testosteroni , Biodegradação Ambiental , Reatores Biológicos , Piridinas , Esgotos
11.
PLoS Biol ; 15(8): e2002176, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28763438

RESUMO

Enhancing brown fat activity and promoting white fat browning are attractive therapeutic strategies for treating obesity and associated metabolic disorders. To provide a comprehensive picture of the gene regulatory network in these processes, we conducted a series of transcriptome studies by RNA sequencing (RNA-seq) and quantified the mRNA and long noncoding RNA (lncRNA) changes during white fat browning (chronic cold exposure, beta-adrenergic agonist treatment, and intense exercise) and brown fat activation or inactivation (acute cold exposure or thermoneutrality, respectively). mRNA-lncRNA coexpression networks revealed dynamically regulated lncRNAs to be largely embedded in nutrient and energy metabolism pathways. We identified a brown adipose tissue-enriched lncRNA, lncBATE10, that was governed by the cAMP-cAMP response element-binding protein (Creb) axis and required for a full brown fat differentiation and white fat browning program. Mechanistically, lncBATE10 can decoy Celf1 from Pgc1α, thereby protecting Pgc1α mRNA from repression by Celf1. Together, these studies provide a comprehensive data framework to interrogate the transcriptomic changes accompanying energy homeostasis transition in adipose tissue.


Assuntos
Tecido Adiposo/metabolismo , Proteínas CELF1/metabolismo , Metabolismo Energético , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Diferenciação Celular , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Transdução de Sinais , Transcriptoma
12.
World J Surg Oncol ; 18(1): 288, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33158448

RESUMO

PURPOSE: The aim of this study is to examine the pattern of lymph node metastasis (lateral vs. mesenteric lymph nodes) in low rectal cancer. METHODS: This retrospective analysis included all patients undergoing laparoscopic total mesorectal excision plus lateral lymph node dissection for advanced low rectal cancer (up to 8 cm from the anal verge) during a period from July 1, 2017, to August 31, 2019, at the Department of Colorectal Surgery, Tianjin Union Medical Center. The decision to conduct lateral lymph node dissection was based on positive findings in preoperative imaging assessments. RESULTS: A total of 42 patients were included in data analysis. Surgery was successfully completed as planned, without conversion to open surgery in any case. A minimum of 10 mesenteric lymph nodes and 1 lateral lymph node on each side were dissected in all patients. Pathologic examination of resected specimens showed no metastasis to either mesenteric or lateral lymph nodes in 7 (16.7%) case, metastasis to both mesenteric and lateral lymph nodes in 26 (61.9%) cases, metastasis to mesenteric but not lateral lymph nodes in 4 (9.5%) cases, and metastasis to lateral but not mesenteric lymph nodes in 5 (11.9%) cases (n = 2 in the obturator region; n = 3 in the iliac artery region). CONCLUSION: A clinically significant proportion of low rectal cancer patients have metastasis to lateral lymph nodes without involvement of mesenteric lymph nodes. More carefully planned prospective studies are needed to verify this preliminary finding.


Assuntos
Neoplasias Retais , Humanos , Excisão de Linfonodo , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Prognóstico , Estudos Prospectivos , Neoplasias Retais/cirurgia , Estudos Retrospectivos
14.
Pestic Biochem Physiol ; 136: 64-69, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28187833

RESUMO

The resistance of the small brown planthopper (SBPH), Laodelphax striatella, to insecticides has been widely found in China, and has posed serious problems to efforts to control the pest. To determine the costs and benefits of resistance, the life tables of chlorpyrifos-resistant and -susceptible strains were constructed at 24 and 30°C. The results showed the resistant SBPH (YN-CPF) had lower fitness at 24°C, but slightly higher fitness at 30°C compared to the susceptible SBPH. Transcriptomic analysis showed there are five heat shock protein genes changed their expression, and the up-regulated genes are LsHsc70-1 and LsHsc70-2. The deduced amino acid sequences of LsHsc70-1 and LsHsc70-2 include three heat shock protein 70 (HSP70) family signatures, but LsHSC70-1 has the conserved HSP70 carboxyl terminal region of the "EEVD" motif, while LsHSC70-2 has the endoplasmic reticulum (ER) retention signal of the "KDEL" motif. The phylogenetic tree further identified LsHsc70-1 has closer evolutionary distances to cytoplasmic/nuclear HSP70s from human and Drosophila melanogaster, while LsHsc70-2 has closer evolutionary distances to HSP70s localized to ER. After treatment at 30-44°C, the expression of LsHsc70-1 and LsHsc70-2 was slightly increased in YN-CPF. These results suggested that LsHsc70-1 and LsHsc70-2 are members of Hsc70 family, localized to the cytosol/nucleus and ER, respectively. The up-regulated expression of these genes may protect the chlorpyrifos-resistant pest against damage under high temperatures, increasing its relative fitness, but the lower relative fitness of this population under optimal temperature may be the trade-off.


Assuntos
Proteínas de Choque Térmico HSP70/genética , Hemípteros/genética , Temperatura Alta/efeitos adversos , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Animais , Clorpirifos , Feminino , Fertilidade/genética , Expressão Gênica , Hemípteros/efeitos dos fármacos , Hemípteros/fisiologia , Inseticidas , Características de História de Vida , Masculino
16.
J Hepatol ; 63(6): 1466-75, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26272872

RESUMO

BACKGROUND & AIMS: Due to the protective effect of estrogen against hepatic fat accumulation, the prevalence of non-alcoholic fatty liver disease (NAFLD) in premenopausal women is lower than that in men at the same age and in postmenopausal women. Our study was to further elucidate an underlying mechanism by which estrogen prevents NAFLD from miRNA perspective in female mice. METHODS: miRNA expression was evaluated by TaqMan miRNA assay. Luciferase and ChIP assay were done to validate regulation of miR-125b by estrogen via estrogen receptor alpha (ERα). Nile red and Oil red O staining were used to check lipid content. Overexpressing or inhibiting the physiological role of miR-125b in the liver of mice through injecting adenovirus were used to identify the function of miR-125b in vivo. RESULTS: miR-125b expression was activated by estrogen via ERα in vitro and in vivo. miR-125b inhibited lipid accumulation both in HepG2 cells and primary mouse hepatocytes. Consistently, ovariectomized or liver-specific ERα knockdown mice treated with miR-125b overexpressing adenoviruses were resistant to hepatic steatosis induced by high-fat diet, due to decreased fatty acid uptake and synthesis and decreased triglyceride synthesis. Conversely, inhibiting the physiological role of miR-125b with a sponge decoy slightly promoted liver steatosis with a high-fat diet. Notably, we provided evidence showing that fatty acid synthase was a functional target of miR-125b. CONCLUSION: Our findings identify a novel mechanism by which estrogen protects against hepatic steatosis in female mice via upregulating miR-125b expression.


Assuntos
Estrogênios/metabolismo , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Animais , Dieta Hiperlipídica/efeitos adversos , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ovariectomia , Regulação para Cima
17.
J Econ Entomol ; 108(3): 1289-97, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26470257

RESUMO

Acetylcholinesterase (AChE) is the target of organophosphate (OP) and carbamate insecticides. Mutations in the AChE gene (ace) leading to decreased insecticide susceptibility is the main resistance mechanism in insects. In this study, two Chilo auricilius acetylcholinesterase genes, designated as Caace1 and Caace2, were cloned using RT-PCR and RACE. Caace1 cDNA is 2534 bp, with ORF of 2082 bp, and it encodes an acetylcholinesterase 1 (CaAChE1) protein comprising a calculated 693 amino acid (aa) residues. Caace2 cDNA contains 2280 bp, with a full-length ORF of 1917 bp, encoding acetylcholinesterase 2 (CaAChE2) comprising a calculated 638 aa residues. At the aa level, CaAChE1 displays the highest similarity (97%) with the Chilo suppressalis AChE1, and CaAChE2 shows the highest similarity with the C. suppressalis AChE2 (99%). From the restriction fragment length polymorphism (RFLP) PCR (RFLP-PCR) analysis, one mutation in Caace1, similar to the ace1 mutation associated with triazophos resistance in C. suppressalis, was detected. Detailed examination of field populations of C. auricilius indicated this resistance mutation in C. auricilius is still quite infrequent. Based on the assay of AChE activity and RFLP-PCR testing, an individual that contains resistance mutation has lower AChE activities, while the individual that does not contain the resistance mutation has higher AChE activities. This study provides a basis for future investigations into the mechanism of OP resistance in C. auricilius, as well as a guidance for C. auricilius control with reasonable choice of pesticides.


Assuntos
Acetilcolinesterase/genética , Proteínas de Insetos/genética , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Mariposas/genética , Organotiofosfatos/farmacologia , Triazóis/farmacologia , Acetilcolinesterase/metabolismo , Sequência de Aminoácidos , Animais , China , DNA Complementar/genética , DNA Complementar/metabolismo , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Dados de Sequência Molecular , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Filogenia , Alinhamento de Sequência
18.
J Biol Chem ; 288(12): 8222-8230, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23389033

RESUMO

BMP4 has been shown to induce C3H10T1/2 pluripotent stem cells to commit to adipocyte lineage. In addition to several proteins identified, microRNAs also play a critical role in the process. In this study, we identified microRNA-140 (miR-140) as a direct downstream component of the BMP4 signaling pathway during the commitment of C3H10T1/2 cells to adipocyte lineage. Overexpression of miR-140 in C3H10T1/2 cells promoted commitment, whereas knockdown of its expression led to impairment. Additional studies indicated that Ostm1 is a bona fide target of miR-140, which is significantly decreased during commitment, and Ostm1 was also demonstrated to function as an anti-adipogenic factor.


Assuntos
Adipócitos/metabolismo , Proteínas de Membrana/genética , MicroRNAs/fisiologia , Células-Tronco Pluripotentes/fisiologia , Interferência de RNA , Células 3T3-L1 , Adipogenia/genética , Animais , Sequência de Bases , Proteína Morfogenética Óssea 4/fisiologia , Proteínas de Membrana/metabolismo , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C3H , MicroRNAs/genética , MicroRNAs/metabolismo , Ativação Transcricional
19.
BMC Mol Biol ; 15: 28, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25515331

RESUMO

BACKGROUND: Transposable elements (TEs, transposons) are mobile genetic DNA sequences. TEs can insert copies of themselves into new genomic locations and they have the capacity to multiply. Therefore, TEs have been crucial in the shaping of hosts' current genomes. TEs can be utilized as genetic markers to study population genetic diversity. The rice stem borer Chilo suppressalis Walker is one of the most important insect pests of many subtropical and tropical paddy fields. This insect occurs in all the rice-growing areas in China. This research was carried out in order to find diversity between C. suppressalis field populations and detect the original settlement of C. suppressalis populations based on the piggyBac-like element (PLE). We also aim to provide insights into the evolution of PLEs in C. suppressalis and the phylogeography of C. suppressalis. RESULTS: Here we identify a new piggyBac-like element (PLE) in the rice stem borer Chilo suppressalis Walker, which is called CsuPLE1.1 (GenBank accession no. JX294476). CsuPLE1.1 is transcriptionally active. Additionally, the CsuPLE1.1 sequence varied slightly between field populations, with polymorphic indels (insertion/deletion) and hyper-variable regions including the identification of the 3' region outside the open reading frame (ORF). CsuPLE1.1 insertion frequency varied between field populations. Sequences variation was found between CsuPLE1 copies and varied within and among field populations. Twenty-one different insertion sites for CsuPLE1 copies were identified with at least two insertion loci found in all populations. CONCLUSIONS: Our results indicate that the initial invasion of CsuPLE1 into C. suppressalis occurred before C. suppressalis populations spread throughout China, and suggest that C. suppressalis populations have a common ancestor in China. Additionally, the lower reaches of the Yangtze River are probably the original settlement of C. suppressalis in China. Finally, the CsuPLE1 insertion site appears to be a candidate marker for phylogenetic research of C. suppressalis.


Assuntos
Elementos de DNA Transponíveis , Genes de Insetos , Mariposas/genética , Sequência de Aminoácidos , Distribuição Animal , Animais , Sequência de Bases , China , Evolução Molecular , Mutação INDEL , Dados de Sequência Molecular , Filogenia , Filogeografia , Polimorfismo Genético , Análise de Sequência de DNA , Transcrição Gênica
20.
Sci Total Environ ; 917: 170396, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38301783

RESUMO

Current techniques for microplastics (MPs) analysis are diverse. However, most techniques have individual limitations like the detection limit of spatial resolution, susceptibility, high cost, and time-consuming detection. In this study, we proposed a multi-spectroscopy method coupling µ-FTIR and µ-Raman analysis for one-stop MPs detection, in which barium fluoride was used as the substrate alternative to the filter membrane. Compared with commonly used filter membranes (alumina, silver, PTFE and nylon membranes), the barium fluoride substrate showed better spectroscopic detection performance on microscopic observation, broader transmittable wavenumber range for µ-FTIR (750-4000 cm-1) and µ-Raman (250-4000 cm-1) detection, thus suitable for the multi-spectroscopy analysis of spiked samples. Further, the real environmental and biological samples (indoor air, bottled water and human exhaled breath) were collected and detected to verify the applicability of the developed multi-spectroscopy method. The results indicated that the average content of detected MPs could be increased by 30.4 ± 29.9 % for indoor air, 17.1 ± 13.2 % for bottled water and 38.4 ± 16.0 % for human exhaled breath, respectively in comparison with widely used µ-Raman detection, which suggested that MPs exposure might be underestimated using single spectroscopy detection. Moreover, the majority of underestimated MPs were colored and smaller sized (<50 µm) MPs, which could pose higher risks to human body. In addition, the proposed method consumed lower sample pre-treatment costs and was environmental-friendly since the barium fluoride substrate could be used repeatedly after being cleaned by organic solvent with reliable results (n = 10, CV = 10 %, ICC = 0.961), which reduced the cost of MPs detection by at least 2.49 times compared with traditional methods using silver membrane.


Assuntos
Compostos de Bário , Água Potável , Fluoretos , Poluentes Químicos da Água , Humanos , Microplásticos , Plásticos/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Água Potável/análise , Prata/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise
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