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Breast cancer is a high-risk disease with a high mortality rate among women. Chemotherapy plays an important role in the treatment of breast cancer. However, chemotherapy eventually results in tumours that are resistant to drugs. In recent years, many studies have revealed that the activation of Wnt/β-catenin signalling is crucial for the emergence and growth of breast tumours as well as the development of drug resistance. Additionally, drugs that target this pathway can reverse drug resistance in breast cancer therapy. Traditional Chinese medicine has the properties of multi-target and tenderness. Therefore, integrating traditional Chinese medicine and modern medicine into chemotherapy provides a new strategy for reversing the drug resistance of breast tumours. This paper mainly reviews the possible mechanism of Wnt/β-catenin in promoting the process of breast tumour drug resistance, and the progress of alkaloids extracted from traditional Chinese medicine in the targeting of this pathway in order to reverse the drug resistance of breast cancer.
The coronavirus disease 2019 (COVID-19) outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2 virus) has been sustained in China since December 2019, and has become a pandemic. The mental health of frontline medical staff is a concern. In this study, we aimed to identify the factors influencing medical worker anxiety in China during the COVID-19 outbreak. We conducted a cross-sectional study to estimate the prevalence of anxiety among medical staff in China from 10 February 2020 to 20 February 2020 using the Zung Self-rating Anxiety Scale (SAS) to assess anxiety, with the criteria of normal (⩽49), mild (50–59), moderate (60–70) and severe anxiety (⩾70). We used multivariable linear regression to determine the factors (e.g. having direct contact when treating infected patients, being a medical staff worker from Hubei province, being a suspect case) for anxiety. We also used adjusted models to confirm independent factors for anxiety after adjusting for gender, age, education and marital status. Of 512 medical staff in China, 164 (32.03%) had had direct contact treating infected patients. The prevalence of anxiety was 12.5%, with 53 workers suffering from mild (10.35%), seven workers suffering from moderate (1.36%) and four workers suffering from severe anxiety (0.78%). After adjusting for sociodemographic characteristics (gender, age, education and marital status), medical staff who had had direct contact treating infected patients experienced higher anxiety scores than those who had not had direct contact (β value = 2.33, confidence interval (CI) 0.65–4.00; P = 0.0068). A similar trend was observed in medical staff from Hubei province, compared with those from other parts of China (β value = 3.67, CI 1.44–5.89; P = 0.0013). The most important variable was suspect cases with high anxiety scores, compared to non-suspect cases (β value = 4.44, CI 1.55–7.33; P = 0.0028). In this survey of hospital medical workers during the COVID-19 outbreak in China, we found that study participants experienced anxiety symptoms, especially those who had direct clinical contact with infected patients; as did those in the worst affected areas, including Hubei province; and those who were suspect cases. Governments and healthcare authorities should proactively implement appropriate psychological intervention programmes, to prevent, alleviate or treat increased anxiety.
Bimetallic nanoparticles (NPs) have attracted a great deal of attention due to the synergistic interaction between metal components. In this work, the thermal process in which the reducing agent is not expensive or hazardous as those in traditional methods was employed to prepare alloy Ag–Cu NPs. The molar ratio between Ag and Cu was varied from 1:9 to 9:1. Nearly monodisperse NPs with alloy structure were characterized by X-ray diffraction and high-resolution transmission electron microscopy with energy dispersive spectroscopy In comparison with monometallic Ag and Cu NPs, the alloyed Ag–Cu NPs showed better monodispersity, especially when the ratio between Ag and Cu was 1:1. Moreover, the alloyed Ag–Cu NPs exhibited enhanced resistance to electromigration and oxidation, the respective problem of pure Ag and Cu. The alloyed Ag–Cu NPs also exhibited improved properties than a mixture of Ag–Cu NPs. This study should serve as the foundation for exploring high performance alloyed bimetallic NPs.
The long-lived radioisotope 59Ni is of interest in various research fields including neutron dosimetry, radioactive waste management, and astrophysics. In order to achieve the sensitivity required for such applications, the technique of accelerator mass spectrometry (AMS) 59Ni measurement has been developed at the AMS facility at China Institute of Atomic Energy (CIAE). Based on the AE-Q3D detection system in the CIAE AMS facility, the interference in 59Ni counting from the isobar 59Co has been reduced by a factor of 8 × 106. A series of laboratory reference samples and a blank sample were measured to check the performance of 59Ni measurement. A detection sensitivity of about 5 × 10−13 (59Ni/Ni) has been obtained.
Excessive gestational weight gain and postpartum weight retention are risk factors for female obesity. The present study was to examine dietary intakes and weight history from a prospective follow-up study from early pregnancy to 1 year postpartum. A total of 151 pregnant women within 20 weeks of pregnancy in Taipei, Taiwan were interviewed periodically to collect dietary and lifestyle information. The participants had an average age of 30 years and the average gestational weight gain was 14 kg, with an average daily intake of 7830 kJ (1870 kcal) in the 1 year following parturition. By bivariate analyses, maternal age, pre-pregnancy BMI and breast-feeding were not related to postpartum weight retention, but gestational weight gain had significant positive correlations (r 0·54 at 6 months, r 0·44 at 1 year; P < 0·05). The generalised estimating equations showed that the average weight before pregnancy, at 6 months and 1 year postpartum was 53·35 kg, 55·75 kg (weight retention 2·36 kg; P < 0·01) and 54·75 kg (weight retention 1·48 kg; P < 0·01), respectively. After controlling for age, pre-pregnancy BMI, gestational weight gain and parity, we found at 6 months that the adjusted weight retention at postpartum was 0·79 kg (P < 0·01), but at 1 year it was − 0·08 kg (P>0·05). From multivariate analyses, dietary energy intake and energy intake per kg body weight as a long-term physical activity index could explain 24 % of the variation at 6 months and 27 % of the variation at 1 year in postpartum weight retention. These results suggest that pregnant women should be advised to control gestational weight gain, decrease energy intakes after child-bearing and maintain regular exercise in order to prevent postpartum obesity.
A full-length cry1Ia gene fragment, obtained by polymerase chain reaction (PCR) amplification with a pair of primers designed according to cry1Ia-type gene sequences and DNA from Bacillus thuringiensis as template, was introduced into the expression vector pET-21b and transformed into Escherichia coli BL21(DE3). The molecular weight of the induced expression product was 81.2 kDa. The amino acid sequence of Cry1Ia was very different from sequences of 12 known Cry1Ia-type proteins. This gene was designated as cry1Ia8 by the International B. thuringiensis Insecticidal Protein Nomenclature Committee (accession number AF373207). The bioassay results indicated that Cry1Ia toxin protein showed distinct insecticidal activity against Ostrinia furnacalis and Plutella xylostella with LC50 of 0.268 μg/g and 2.227 μg/ml, respectively. It also had insecticidal activity against Leguminivora glycinivorella, but not against Pyrrhalta aenescens. The novel cry1Ia8 gene will be an important resource in constructing genetically engineered bacteria and transgenic plants for biocontrol of insect pests. It is also available for screening gene stacks to delay pest resistance.
Embryonic germ (EG) cells are pluripotent cells derived from the primordial germ cells of gonads, gonadal ridges and mesenteries, and analogies of foetuses, with the ability to undergo both self-renewal and multiple differentiation. These cells can differentiate into derivatives of all three embryonic germ layers when transferred to an in vitro environment and have the ability to form any fully differentiated cell of the body. The present paper investigates some factors influencing the efficiency of isolation and culture of human EG cells, such as foetus age, culture serum, added cytokines and feeder cells. The results demonstrate that foetuses of 7–12 weeks are optimal for in vitro culture of human EG cells. The basic medium consisted of DMEM, 1×non-essential amino acids, 2 mM l-glutamine and 1 mM sodium pyruvate. Supplementation with 15% foetal bovine serum, 4 ng/ml human recombinant leukaemia inhibitory factor, 4 ng/ml basic fibroblast growth factor and 20 ng/ml stem cell factor clearly improved the efficiency of isolation and culture of human EG cells. Murine embryonic fibroblasts were better feeder cells than human embryonic fibroblasts, bovine embryonic fibroblasts or STO cell line.
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