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OBJECTIVE: To compare the prognostic value of net water uptake (NWU) and target mismatch (TM) on CT perfusion (CTP) in acute ischemic stroke (AIS) patients with late time window. METHODS: One hundred and nine consecutive AIS patients with anterior-circulation large vessel occlusion presenting within 6-24 h from onset/last seen well were enrolled. Automated Alberta Stroke Program Early CT Score-based NWU (ASPECTS-NWU) was calculated from admission CT. The correlation between ASPECTS-NWU and CTP parameters was assessed. Predictors for favorable outcome (modified Rankin Scale score ≤ 2) at 90 days were assessed using logistic regression analysis. The ability of outcome prediction between ASPECTS-NWU and TM (an ischemic core < 70 mL, a mismatch ratio ≥ 1.8, and an absolute difference ≥ 15 mL) was compared using receiver operating characteristic (ROC) curve. RESULTS: A higher level of ASPECTS-NWU was associated with a larger ischemic core (r = 0.66, p < 0.001) and a larger hypoperfusion volume (r = 0.38, p < 0.001). ASPECTS-NWU performed better than TM for outcome stratification (area under the curve [AUC], 0.738 vs 0.583, p = 0.004) and was the only independent neuroimaging marker associated with favorable outcomes compared with CTP parameters (odds ratio, 0.73; 95% confidence interval [CI] 0.62-0.87, p < 0.001). An outcome prediction model including ASPECTS-NWU and clinical variables (National Institutes of Health Stroke Scale scores and age) yielded an AUC of 0.828 (95% CI 0.744-0.893; sensitivity 65.4%; specificity 87.7%). CONCLUSION: ASPECTS-NWU performed better than TM for outcome prediction in AIS patients with late time window and might be an alternative imaging biomarker to CTP for patient selection. CLINICAL RELEVANCE STATEMENT: Automated Alberta Stroke Program Early CT Score-based net water uptake outperforms target mismatch on CT perfusion for the outcome prediction in patients with acute ischemic stroke and can be an alternative imaging biomarker for patient selection in late therapeutic window. KEY POINTS: ⢠A higher ASPECTS-based net water uptake was associated with larger ischemic cores and hypoperfusion volumes on CT perfusion. ⢠ASPECTS-based net water uptake outperformed target mismatch for outcome prediction in acute ischemic stroke with extended therapeutic window. ⢠ASPECTS-based net water uptake can be an alternative biomarker to target mismatch for selecting acute ischemic stroke patients with late therapeutic window.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Água , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Prognóstico , Biomarcadores , Resultado do Tratamento , TrombectomiaRESUMO
Ampelopsis grossedentata (AG) is mainly distributed in Chinese provinces and areas south of the Yangtze River Basin. It is mostly concentrated or scattered in mountainous bushes or woods with high humidity. Approximately 57 chemical components of AG have been identified, including flavonoids, phenols, steroids and terpenoids, volatile components, and other chemical components. In vitro studies have shown that the flavone of AG has therapeutic properties such as anti-bacteria, anti-inflammation, anti-oxidation, enhancing immunity, regulating glucose and lipid metabolism, being hepatoprotective, and being anti-tumor with no toxicity. Through searching and combing the related literature, this paper comprehensively and systematically summarizes the research progress of AG, including morphology, traditional and modern uses, chemical composition and structure, and pharmacological and toxicological effects, with a view to providing references for AG-related research.
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Ampelopsis , Medicamentos de Ervas Chinesas , Plantas Medicinais , Ampelopsis/química , Medicamentos de Ervas Chinesas/química , Flavonoides/farmacologia , Flavonoides/química , Glucose , Compostos Fitoquímicos/farmacologia , Etnofarmacologia , Extratos Vegetais/químicaRESUMO
OBJECTIVE: To investigate the value of automated Alberta Stroke Program Early CT Score (ASPECTS)-based net water uptake (NWU) to predict tissue-level reperfusion status and 90-day functional outcomes in acute ischemic stroke (AIS) patients after reperfusion therapy. METHODS: One hundred and twelve patients with AIS who received reperfusion therapy were enrolled. ASPECTS-NWU was calculated from admission CT (NWUadmission) and follow-up CT (NWUFCT), and the difference (ΔNWU) was calculated. Tissue-level reperfusion status was evaluated via follow-up arterial spin labeling imaging. The relationship between ASPECTS-NWU and tissue-level reperfusion was evaluated. Predictors of 90-day unfavorable outcomes (modified Rankin Scale score > 2) were assessed by multivariate logistic regression analysis and receiver operating characteristic (ROC) curves. RESULTS: Poor reperfusion was observed in 40 patients (35.7%) after therapy. Those patients had significantly elevated NWUFCT (median, 14.15% vs. 8.08%, p = 0.018) and higher ΔNWU (median, 4.12% vs. -2.03%, p < 0.001), compared to patients with good reperfusion. High ΔNWU was a significant marker of poor reperfusion despite successful recanalization. National Institutes of Health Stroke Scale score at admission (odds ratio [OR], 1.11; 95% confidence interval [CI] 1.03-1.20, p = 0.007) and ΔNWU (OR, 1.07; 95% CI 1.02-1.13, p = 0.008) were independently associated with unfavorable outcomes. An outcome prediction model including both parameters yields an area under the curve of 0.762 (sensitivity 70.3%, specificity, 84.2%). CONCLUSIONS: Elevated NWUFCT and higher ΔNWU were associated with poor tissue-level reperfusion after therapy. Higher ΔNWU was an independent predictor of poor reperfusion and unfavorable neurological outcomes despite successful recanalization. KEY POINTS: ⢠ASPECTS-NWU may provide pathophysiological information about tissue-level reperfusion status and offer prognostic benefits for patients with AIS after reperfusion therapy. ⢠Elevated NWUFCT and higher ΔNWU were correlated with poor tissue-level reperfusion after therapy. ⢠A higher ΔNWU is an independent predictor of poor reperfusion and 90-day unfavorable outcomes despite successful recanalization.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Alberta , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Humanos , Reperfusão , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Resultado do Tratamento , ÁguaRESUMO
Macleaya cordata extracts (MCE) are listed as feed additives in animal production by the European Food Authority. The core components of MCE are mainly sanguinarine (SA) and chelerythrine (CHE). This study aims to investigate sex differences in the pharmacokinetics and tissue residues of MCE in rats.Male and female rates were intragastrically administered MCE (1.25 mg·kg-1 body weight and 12.5 mg·kg-1 body weight dose for 28 days). SA and CHE concentrations were determined using high-performance liquid chromatography/tandem mass spectrometry.The peak plasma concentration (Cmax) and area under the curve (AUC) of both CHE and SA were higher in female than in male rats (12.5 mg·kg-1 body weight group), whereas their half-life (T1/2) and apparent volume of distribution (Vd) was lower (p < 0.05). Tissue rfesidue analysis indicated that SA and CHE were more distributed in male than in female rats and were highly distributed in the caecum and liver. SA and CHE were completely eliminated from the liver, kidney, lung, heart, spleen, leg muscle, and caecum after 120 h, indicating they did not accumulate in rats for a long time.Overall, we found that the pharmacokinetics and tissue residues of SA and CHE of male and female rats showed sex differences.
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Papaveraceae , Caracteres Sexuais , Animais , Cromatografia Líquida de Alta Pressão , Feminino , Masculino , Espectrometria de Massas , Papaveraceae/química , Extratos Vegetais , RatosRESUMO
MnCoGe-based compounds undergo a giant negative thermal expansion (NTE) during the martensitic structural transition from Ni2In-type hexagonal to TiNiSi-type orthorhombic structure. High-resolution neutron diffraction experiments revealed that the expansion of unit cell volume can be as large as ΔV/V â¼ 3.9%. The optimized compositions with concurrent magnetic and structural transitions have been studied for magnetocaloric effect. However, these materials have not been considered as NTE materials partially due to the limited temperature window of phase transition. The as-prepared MnCoGe-based compounds are quite brittle and naturally collapse into powders. By using a few percents (3-4%) of epoxy to bond the powders, we introduced residual stress in the bonded samples and thus realized the broadening of structural transition by utilizing the specific characteristics of lattice softening enforced by the stress. As a result, giant NTE (not only the linear NTE coefficient α but also the operation-temperature window) has been achieved. For example, the average αÌ as much as -51.5 × 10(-6)/K with an operating temperature window as wide as 210 K from 122 to 332 K has been observed in a bonded MnCo0.98Cr0.02Ge compound. Moreover, in the region between 250 and 305 K near room temperature, the α value (-119 × 10(-6)/K) remains nearly independent of temperature. Such an excellent performance exceeds that of most other materials reported previously, suggesting it can potentially be used as a NTE material, particularly for compensating the materials with large positive thermal expansions.
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OBJECTIVE: To preliminarily explore the association of rs12979860 and rs8099917 SNPs with chronic HCV infection in Chinese Han children. METHODS: Chronic HCV infection patients (n=277; 1-17 years old, 4.5 years old in average) and healthy subjects (n=150, children; 2-17 years old, 5.2 years old in average) were recruited and tested by PCR combining direct sequencing. The differences between the rs12979860 and rs8099917 genotypes in patients and healthy subjects were compared. RESULTS: The genetic variations at rs12979860 and rs8099917 in chronic hepatitis C (CHC) children and healthy subjects did not differ significantly. The frequency of spontaneous clearance in CHC children was higher (47%), which is related to the genetic variations. The histological changes of patients were more significant compared to their clinical and biochemical indices, but they did not correlate with the genetic mutations at rs12979860 and rs8099917 significantly. CONCLUSION: The rs12979860 and rs8099917 SNPs are independent factors predicting the spontaneous clearance of Chinese CHC children patients. The correlation between diseases outcomes are in need of further study.
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Robot-assisted surgery has evolved into a crucial treatment for prostate cancer (PCa). However, from its appearance to today, brain-computer interface, virtual reality, and metaverse have revolutionized the field of robot-assisted surgery for PCa, presenting both opportunities and challenges. Especially in the context of contemporary big data and precision medicine, facing the heterogeneity of PCa and the complexity of clinical problems, it still needs to be continuously upgraded and improved. Keeping this in mind, this article summarized the 5 stages of the historical development of robot-assisted surgery for PCa, encompassing the stages of emergence, promotion, development, maturity, and intelligence. Initially, safety concerns were paramount, but subsequent research and engineering advancements have focused on enhancing device efficacy, surgical technology, and achieving precise multi modal treatment. The dominance of da Vinci robot-assisted surgical system has seen this evolution intimately tied to its successive versions. In the future, robot-assisted surgery for PCa will move towards intelligence, promising improved patient outcomes and personalized therapy, alongside formidable challenges. To guide future development, we propose 10 significant prospects spanning clinical, research, engineering, materials, social, and economic domains, envisioning a future era of artificial intelligence in the surgical treatment of PCa.
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Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Humanos , Masculino , Procedimentos Cirúrgicos Robóticos/métodos , Procedimentos Cirúrgicos Robóticos/história , Procedimentos Cirúrgicos Robóticos/tendências , Neoplasias da Próstata/cirurgia , Inteligência Artificial/tendênciasRESUMO
BACKGROUND: Pulmonary artery (PA) aneurysms are usually diagnosed radiographically and present as small or large lesions resembling inflammation or a neoplasm on chest radiography. It has rarely been reported as an endobronchial mass. CASE SUMMARY: We report the case of a 64-year-old man who presented with recurrent hemoptysis. Bronchoscopy revealed a tumorous protrusion blocking the right middle lobe bronchus, which was confirmed to be a PA aneurysm using endobronchial ultrasound bronchoscopy and computed tomography angiography. CONCLUSION: Although endobronchial PA aneurysms are rare, bronchoscopists need to add this lesion to the list of endobronchial masses for which a biopsy is to be assiduously avoided.
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This study aimed to assess the feasibility of using magnetic resonance imaging (MRI)-based Delta radiomics characteristics extrapolated from the Ax LAVA + C series to identify intermediary- and high-risk factors in patients with cervical cancer undergoing surgery following neoadjuvant chemoradiotherapy. A total of 157 patients were divided into two groups: those without any intermediary- or high-risk factors and those with one intermediary-risk factor (negative group; n = 75). Those with any high-risk factor or more than one intermediary-risk factor (positive group; n = 82). Radiomics characteristics were extracted using Ax-LAVA + C MRI sequences. The data was divided into training (n = 126) and test (n = 31) sets in an 8:2 ratio. The training set data features were selected using the Mann-Whitney U test and the Least Absolute Shrinkage and Selection Operator (LASSO) test. The best radiomics features were then analyzed to build a preoperative predictive radiomics model for predicting intermediary- and high-risk factors in cervical cancer. Three models-the clinical model, the radiomics model, and the combined clinic and radiomics model-were developed in this study utilizing the random forest Algorithm. The receiver operating characteristic (ROC) curve, decision curve analysis (DCA), accuracy, sensitivity, and specificity were used to assess the predictive efficacy and clinical benefits of each model. Three models were developed in this study to predict intermediary- and high-risk variables associated with postoperative pathology for patients who underwent surgery after receiving neoadjuvant radiation. In the training and test sets, the AUC values assessed using the clinical model, radiomics model, and combined clinical and radiomics models were 0.76 and 0.70, 0.88 and 0.86, and 0.91 and 0.89, respectively. The use of machine learning algorithms to analyze Delta Ax LAVA + C MRI radiomics features can aid in the prediction of intermediary- and high-risk factors in patients with cervical cancer receiving neoadjuvant therapy.
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Terapia Neoadjuvante , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Algoritmos , Instituições de Assistência Ambulatorial , Fatores de RiscoRESUMO
The plant species Gelsemium elegans Benth. (GEB) promotes pig and sheep growth; however, little is known about its effects in chickens. In this study, a GEB extract (GEBE) was prepared, and its effects on the growth, slaughter, antioxidant performance, meat quality, serum biochemical indices, intestinal morphology, and microflora of yellow-feathered chickens were evaluated. In total, 600 chickens aged 15 days were randomly divided into four groups with five replicates each and fed a basal diet containing 0% (control), 0.25% (0.25 GEBE), 0.75% (0.75 GEBE), or 1.25% (1.25 GEBE) GEBE until 49 days of age. Chickens were then killed, and their meat, organs, and serum and cecal contents were collected. GEBE reduced the feed conversion ratio, particularly in the 0.75 and 1.25 GEBE groups. Furthermore, the GEBE diet improved meat tenderness and reduced the meat expressible moisture content and liver malondialdehyde content, indicating high meat quality. Whereas the 0.25 GEBE diet increased the level of Lactobacillus acidophilus in the cecum, the 0.75 GEBE diet decreased the Escherichia coli level therein. These findings demonstrate that GEBE may improve the meat quality and cecal microbiota of yellow-feathered chickens, providing a basis for identifying candidate alternatives to conventional antibiotics as growth promoting feed additives.
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Background: Intracranial atherosclerotic disease (ICAD) is the major cause of ischemic stroke. Despite aggressive medical therapy, around 15% of patients with ICAD experience recurrence. The aim of the present study was to evaluate the temporal changes in intracranial arteriosclerotic plaques after medical treatment based on vessel wall magnetic resonance imaging (VWMRI) and to explore their relationship with stroke recurrence. Methods: A total of 67 symptomatic patients with ICAD who underwent initial and follow-up VWMRI were recruited into this retrospective cohort study. Stroke recurrence was defined as an ipsilateral stroke symptom after the initial attack. The clinical characteristics and plaque features, including stenosis ratio (measured based on luminal diameter or area), plaque thickness, plaque burden (PB), enhancement ratio (ER), and enhancement grade, were evaluated and compared between the initial and follow-up examinations. Changes in plaque characteristics were compared between patients with or without recurrence by univariable analyses. Multivariable regression was performed to investigate imaging markers for recurrent stroke. Results: The median interval between baseline and follow-up VWMRI was 334 days. A total of 13 cases (19.4%) experienced a stroke recurrence. After treatment, significant decreases in the stenosis ratio (area), PB, and ER were observed in cases without recurrence (all P<0.05), while no significant difference in plaque features was found for cases with recurrence. Univariable analyses showed that changes in stenosis ratio (area), plaque thickness, PB, and ER were significantly different between patients with and without recurrence (all P<0.05). Multivariable regression indicated that PB change was the only significant marker associated with stroke recurrence [odds ratio (OR) =1.112 per 1% increase, 95% confidence interval (CI): 1.010 to 1.224, P=0.031]. Conclusions: Patients with arteriosclerotic plaques who benefit from medical treatment show obvious decreases in stenosis (area), PB, and ER. The progression of PB may serve as an independent marker for predicting stroke recurrence.
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AIM: To investigate whether nerve growth factor (NGF) induced angiogenesis of bone marrow mesenchymal stem cells (MSCs) and the underlying mechanisms. METHODS: Bone marrow MSCs were isolated from femors or tibias of Sprague-Dawley rat, and cultured. The cells were purified after 3 to 5 passages, seeded on Matrigel-coated 24-well plates and treated with NGF. Tube formation was observed 24 h later. Tropomyosin-related kinase A (TrkA) and p75NTR gene expression was examined using PCR analysis and flow cytometry. Growth curves were determined via cell counting. Expression of VEGF and pAkt/Akt were analyzed with Western blot. RESULTS: NGF (25, 50, 100 and 200 µg/L) promoted tube formation of MSCs. The tubular length reached the maximum of a 2.24-fold increase, when the cells were treated with NGF (50 µg/L). NGF (50 µg/L) significantly enhanced Akt phosphorylation. Pretreatment with the specific PI3K inhibitor LY294002 (10 µmol/L) blocked NGF-stimulated Akt phosphorylation, tube formation and angiogenesis. NGF (25-200 µg/L) did not affect the expression of TrkA and vascular endothelial growth factor (VEGF), but significantly suppressed the expression of p75NTR. NGF (50 µg/L) markedly increased the proliferation of MSCs. CONCLUSION: NGF promoted proliferation of MSCs and activated the PI3K/Akt signaling pathway, which may be responsible for NGF induction of MSC angiogenesis.
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Proliferação de Células , Células-Tronco Mesenquimais/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Animais , Células Cultivadas , Ativação Enzimática , Citometria de Fluxo , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
AIM: To characterize the expression and function of midkine (MK) in an in vitro embryonic stem cell (ESC) culture system. METHODS: To investigate the potential roles of MK, the expression of MK in ESCs was evaluated by RT-PCR and immunocytochemistry. The effects of MK on the self-renewal of ESCs were measured using alkaline phosphatase assays, immunocytochemistry, RT-PCR and colony-forming assays. The mechanism of the growth-promoting effect of MK in mESCs was assessed by cell cycle analysis and Western blot analysis. RESULTS: MK is expressed in mouse embryonic stem cells (mESCs), human embryonic stem cells (hESCs) and mouse embryonic fibroblasts (MEFs). MK promotes proliferation and self-renewal of mESCs both in feeder and feeder free culture systems. It also promotes self-renewal and proliferation of hESCs. Further study showed that MK promotes the growth of mESCs by inhibiting apoptosis while accelerating the progression toward the S phase, and enhances mESC self-renewal through PI3K/Akt signaling pathway. CONCLUSION: MK plays profound roles in ESCs. MK/PTPzeta signaling pathway is a novel pathway in the signal network maintaining pluripotency of ESCs. The results extend our knowledge on pluripotency control of ESCs and the relationship between ESCs and cancers.
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Proliferação de Células , Citocinas/metabolismo , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Animais , Ciclo Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Camundongos , Midkina , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Tirosina Fosfatases/metabolismoRESUMO
OBJECTIVE: We investigated the "BURP" maneuver's effect on the association between difficult laryngoscopy and difficult intubation, and predictors of a difficult airway. METHODS: Adult patients who underwent general anesthesia and tracheal intubation from September 2016 to May 2018 were included. The "BURP" maneuver was performed when glottic exposure was classified as Cormack-Lehane grade 3 or 4, suggesting difficult laryngoscopy. The thyromental distance, modified Mallampati score, and interincisor distance were assessed before anesthesia. RESULTS: Among this study's 2028 patients, the "BURP" maneuver decreased difficult laryngoscopies from 428 (21.1%) to 124 (6.1%) cases and increased the difficult intubation to difficult laryngoscopy ratio from 53/428 (12.4%) to 52/124 (41.9%). For laryngoscopies classified as difficult without the "BURP" maneuver, the area under the curve (AUC) of the thyromental distance, modified Mallampati score, and interincisor distance was 0.60, 0.57, and 0.66, respectively. In difficult laryngoscopies using the "BURP" maneuver, the AUC of the thyromental distance, modified Mallampati score, and interincisor distance was 0.71, 0.67, and 0.76, respectively. CONCLUSIONS: The "BURP" maneuver improves the laryngoscopic view and assists in difficult laryngoscopies. Compared with difficult laryngoscopies without the "BURP" maneuver, those with the "BURP" maneuver are more closely associated with difficult intubations and are more predictable. Trial registration: www.chictr.org.cn identifier: ChiCTR-ROC- 16009050.
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Anestesia Geral/métodos , Glote/diagnóstico por imagem , Intubação Intratraqueal/métodos , Laringoscopia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral/instrumentação , Feminino , Humanos , Intubação Intratraqueal/instrumentação , Laringoscopia/instrumentação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto JovemRESUMO
To better understand the characteristics and sources of ambient volatile organic compounds (VOCs) in a polluted area in Chengdu, which requires air pollution control, samples were collected hourly at the Shuangliu site from August 2016 to December 2016. Online gas chromatography/mass spectrometry and a flame ionization detector (GC/MS-FID) were used to analyze the mixing ratios and compositions of the VOCs. During the sampling period, the average mixing ratios of the VOCs were (45.15±43.74)×10-9. Alkanes contribute the most to the total volatile organic compounds (TVOCs), followed by aromatics (22%), halocarbon (17%), oxygenated volatile organic compounds (OVOCs; 15%), alkenes (9%), acetylene (7%), and acetonitrile (1%). Acetone, dichloromethane, acetylenes, ethylene, toluene, m/p-xylenes, propane, 1,2-dichloroethane, and methyl ethyl ketone are the dominant species. By calculating the OH loss rate, the chemical reactivity of the VOCs was estimated. Aromatics contribute the most to the total VOC reactivity, followed by alkenes. The most reactive species are styrene, m/p-xylenes, isoprene, and ethylene. Two biomass burning events were detected during the sampling period. The average mixing ratio of TVOCs is 57.65×10-9, which significantly increased during the national holiday. The mixing ratios of several C2-C5 alkenes, halocarbons, and OVOCs increased the most during the national holiday. The diurnal patterns of critical non-methane hydrocarbons (NMHCs) and OVOCs are consistent with the emission sources in this area. The VOC characteristics at the sampling site are mainly influenced by local industrial sources.
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Natural and synthetic progestins may pose a threat to wild fish populations living in receiving waters. In this study, the effects of norethindrone (NET) on the sex differentiation of zebrafish (Dario renio) and the mechanisms underlying these effects were investigated. Juvenile zebrafish (20 days post fertilization, pdf) were exposed to environmentally relevant concentrations (5, 50, 500, and 1000 ng L-1) for 45 d. Sex ratio of the NET-exposed populations, the histology of the gonads and the transcriptional profile of the regulatory genes involved in sex differentiation and steroidogenesis were examined. The results showed that a significantly higher ratio of male/female was induced in the zebrafish populations exposed to NET at concentrations higher than 32.3 ng L-1. Exposure to NET caused acceleration of sexual mature in males and a delay in ovary maturation in female zebrafish. Among the genes regulating sexual differentiation, transcripts of Dmrt1 showed a dose-dependent increase while transcripts of Figa and Fox12 showed a dose-dependent decrease in response to exposure to NET. For genes regulating the steroidogenesis, the expressions of Cyp11a1, Cyp17, Cyp19a1a, and Cyp11b were significantly down-regulated by exposure to NET, while Hsd17b3 expression was significantly up-regulated by exposure to NET at 421.3 and 892.9 ng L-1. For the receptor genes in the gonads, the transcriptional expression of Pgr, Ar, and Mr was significantly up-regulated at 421.3 and 892.9 ng L-1 of NET. For genes involved in the hypothalamic-pituitary axis, the transcriptional expression of Gnrh3 and Pomc was significantly up-regulated by exposure to NET with the exception for Gnrh3 at 4.2 ng L-1. The results demonstrated that exposure to NET at the juvenile stage could affect gonad differentiation and sex ratio, which might be accounted for by the alterations of the transcriptional expressions of genes along the hypothalamic-pituitary-gonadal (HPG) and hypothalamic-pituitary-adrenal (HPA) axes.
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Perfilação da Expressão Gênica , Sistema Hipotálamo-Hipofisário/metabolismo , Noretindrona/farmacologia , Sistema Hipófise-Suprarrenal/metabolismo , Progestinas/farmacologia , Diferenciação Sexual/genética , Peixe-Zebra/genética , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Células Germinativas/efeitos dos fármacos , Células Germinativas/metabolismo , Gônadas/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Masculino , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos , Razão de Masculinidade , Maturidade Sexual , Poluentes Químicos da Água/toxicidadeRESUMO
Synthetic hormones in wastewater effluents released into the aquatic environments may interfere with the normal endocrine systems of fish in receiving streams. Norgestrel (NGT) is a synthetic progestin widely used in oral contraceptives and frequently detected in wastewater effluents. In this study, adult female mosquitofish (Gambusia affinis) were exposed to three environmentally relevant concentrations of norgestrel (NGT) (i.e., 3.6, 35.8, and 368.0â¯ngâ¯L-1) for 42â¯d, fin morphology, histology of the ovary, and reproductive behaviors were evaluated. The results showed that NGT at all three concentrations caused an increased frequency of atretic follicular cells in ovaries and impaired mating behaviors exhibited by males toward the NGT-exposed females. In mosquitofish exposed to NGT at 35.8 and 368â¯ngâ¯L-1, the anal fin of females had an increased length ratio of ray4/ray 6, an increased width of ray 3, and increased number of segments in ray 3. The histopathological analysis showed that exposure to NGT increased the incidence of spermatogenesis in ovaries. Mating behavior was impaired 58.4%, 65.7%, and 76.4% (Pâ¯<â¯0.01 in all cases) when mosquitofish were exposed to NGT at 3.6, 35.6 and 368.0â¯ngâ¯L-1, respectively. The rapid masculinization, the increased frequency of atretic follicles, the incidence of spermatogenesis in the ovary of female fish, and the altered reproductive behaviors suggest that wild populations of mosquitofish could be similarly affected inhabiting in NGT contaminated environments.
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Comportamento Animal/efeitos dos fármacos , Ciprinodontiformes/fisiologia , Norgestrel/toxicidade , Reprodução/efeitos dos fármacos , Caracteres Sexuais , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/efeitos dos fármacos , Animais , Exposição Ambiental/análise , Feminino , Masculino , Oócitos/citologia , Oócitos/efeitos dos fármacos , Ovário/química , Ovário/efeitos dos fármacos , Poluentes Químicos da Água/toxicidadeRESUMO
Memory effect of electric-field control on magnetic behavior in magnetoelectric composite heterostructures has been a topic of interest for a long time. Although the piezostrain and its transfer across the interface of ferroelectric/ferromagnetic films are known to be important in realizing magnetoelectric coupling, the underlying mechanism for nonvolatile modulation of magnetic behaviors remains a challenge. Here, we report on the electric-field control of magnetic properties in wide-band (011)-Pr0.7Sr0.3MnO3/0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 heterostructures. By introducing an electric-field-induced in-plane anisotropic strain field during the cooling process from room temperature, we observe an in-plane anisotropic, nonvolatile modulation of magnetic properties in a wide-band Pr0.7Sr0.3MnO3 film at low temperatures. We attribute this anisotropic memory effect to the preferential seeding and growth of ferromagnetic (FM) domains under the anisotropic strain field. In addition, we find that the anisotropic, nonvolatile modulation of magnetic properties gradually diminishes as the temperature approaches FM transition, indicating that the nonvolatile memory effect is temperature dependent. By taking into account the competition between thermal energy and the potential barrier of the metastable magnetic state induced by the anisotropic strain field, this distinct memory effect is well explained, which provides a promising approach for designing novel electric-writing magnetic memories.
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The most widespread cooling techniques based on gas compression/expansion encounter environmental problems. Thus, tremendous effort has been dedicated to develop alternative cooling technique and search for solid state materials that show large caloric effects. An application of pressure to a material can cause a change in temperature, which is called the barocaloric effect. Here we report the giant barocaloric effect in a hexagonal Ni2In-type MnCoGe0.99In0.01 compound involving magnetostructural transformation, Tmstr, which is accompanied with a big difference in the internal energy due to a great negative lattice expansion(ΔV/V ~ 3.9%). High resolution neutron diffraction experiments reveal that the hydrostatic pressure can push the Tmstr to a lower temperature at a rate of 7.7 K/kbar, resulting in a giant barocaloric effect. The entropy change under a moderate pressure of 3 kbar reaches 52 J kg(-1) K(-1), which exceeds that of most materials, including the reported giant magnetocaloric effect driven by 5 T magnetic field that is available only by superconducting magnets.