Construction of internal electric fields (IEFs) is crucial to realize efficient charge separation for charge-induced redox reactions, such as water splitting and CO
reduction. However, a quantitative ...understanding of the charge transfer dynamics modulated by IEFs remains elusive. Here, electron microscopy study unveils that the non-equilibrium photo-excited electrons are collectively steered by two contiguous IEFs within binary (001)/(200) facet junctions of BiOBr platelets, and they exhibit characteristic Gaussian distribution profiles on reduction facets by using metal co-catalysts as probes. An analytical model justifies the Gaussian curve and allows us to measure the diffusion length and drift distance of electrons. The charge separation efficiency, as well as photocatalytic performances, are maximized when the platelet size is about twice the drift distance, either by tailoring particle dimensions or tuning IEF-dependent drift distances. The work offers great flexibility for precisely constructing high-performance particulate photocatalysts by understanding charge transfer dynamics.
In this study, we compared two experimental methods of selecting terms in expository text to generate reading representations and tested how well these reading representations predicted reading ...comprehension. The two experimental methods were the traditional method of using all terms (all keywords) to create participants' representation networks, and the terms categorization (TC) method of using only important terms (core and branch words). Representation networks were assessed using participants' adjacency scores, ratings of relatedness in pairs of terms, and using summary (summary writing) by all turms. An in-subject design was performed in experiments 1 and 2, and an inter-subject design was performed in experiment 3 to test the hypothesis. With the same sample in exp1 and epx2, a different sample in each exp3. Experiment 1 showed that when using only the traditional way of selecting terms, adjacency was better than relatedness in predicting reading comprehension. Reading representations generated based on the summary method could not predict participants' reading comprehension ability, so this method was excluded from subsequent studies. Experiment 2 showed that the terms selected in Experiment 1 were stronger predictors of reading comprehension when the word pairs included a core term (central to understanding of full text) or a branch term (key to understanding paragraph), relative to a detail term (not affect the understanding full text). Experiment 3 found that whereas the two methods were equally effective in generating representations measured by adjacency, TC was superior in generating representations measured by relatedness. These conclusions have important implications for future research and application.
Objective
The transient receptor potential vanilloid subtype 1 (TRPV1) channel is considered to play an important regulatory role in the process of pain. The purpose of this study is to observe the ...change characteristics of TRPV1 channel in MSU-induced gouty arthritis and to find a new target for clinical treatment of gout pain.
Methods
Acute gouty arthritis was induced by injection of monosodium urate (MSU) crystals into the ankle joint of mice. The swelling degree was evaluated by measuring the circumference of the ankle joint. Mechanical hyperalgesia was conducted using the electronic von Frey. Calcium fluorescence and TRPV1 current were recorded by applying laser scanning confocal microscope and patch clamp in dorsal root ganglion (DRG) neurons, respectively.
Results
MSU treatment resulted in significant inflammatory response and mechanical hyperalgesia. The peak swelling degree appeared at 12 h, and the minimum pain threshold appeared at 8 h after MSU treatment. The fluorescence intensity of capsaicin-induced calcium response and TRPV1 current were increased in DRG cells from MSU-treated mice. The number of cells that increased calcium response after MSU treatment was mainly distributed in small-diameter DRG cells. However, the action potential was not significantly changed in small-diameter DRG cells after MSU treatment.
Conclusions
These findings identified an important role of TRPV1 in mediating mechanical hyperalgesia in MSU-induced gouty arthritis and further suggest that TRPV1 can be regarded as a potential new target for the clinical treatment of gouty arthritis.
Small heat shock proteins (smHSPs) play important and extensive roles in plant defenses against abiotic stresses. We cloned a gene for a smHSP from the David Lily (Lilium davidii (E. H. Wilson) ...Raffill var. Willmottiae), which we named LimHSP16.45 based on its protein molecular weight. Its expression was induced by many kinds of abiotic stresses in both the lily and transgenic plants of Arabidopsis. Heterologous expression enhanced cell viability of the latter under high temperatures, high salt, and oxidative stress, and heat shock granules (HSGs) formed under heat or salinity treatment. Assays of enzymes showed that LimHSP16.45 overexpression was related to greater activity by superoxide dismutase and catalase in transgenic lines. Therefore, we conclude that heterologous expression can protect plants against abiotic stresses by preventing irreversible protein aggregation, and by scavenging cellular reactive oxygen species.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
HER2 mutation has been found to be an oncogenic driver gene in non-small cell lung cancers(NSCLC) and HER2-directed therapies have shown promising results in this unique population, while little is ...known about its association with outcomes of chemotherapy. The aim of this study was to investigate the efficacy of first line chemotherapy in patients with advanced HER2-mutant lung adenocarcinomas.
Patients with advanced NSCLC(N = 1714) initially underwent testing for EGFR, KRAS, BRAF mutations and ALK, ROS1 rearrangements, and negative cases were then assessed for HER2 mutations using the method of amplification refractory mutation system(ARMS). The efficacy of first line pemetrexed-based chemotherapy was investigated in patients with HER2-mutant and those with EGFR-mutant, ALK/ROS1-rearranged and KRAS-mutant advanced adenocarcinomas.
HER2 mutations were detected in 29 of 572(5.1%) specimens from a selected population of EGFR/KRAS/BRAF/ALK/ROS1 negative patients. All of them are adenocarcinomas. Among patients with HER2-mutant lung cancers, 25 received pemetrexed-based first line chemotherapy. The objective response rate(ORR) was 36.0%. Their median progression free survival(PFS) was 5.1 months, which was similar with that of KRAS-mutant group (n = 40,5.0 months, p = 0.971), numerically shorter than that of EGFR-mutant group(n = 74, 6.5 months, p = 0.247) and statistically significantly shorter than that of ALK/ROS1-rearranged group (n = 39,9.2 months, p = 0.004). Furthermore, HER2 variants subgroup analysis showed that PFS was inferior in A775_G776insYVMA group compared with other variants (4.2 vs 7.2 months, p = 0.085).
Patients with advanced HER2-mutant lung adenocarcinomas showed an inferior outcome of first line pemetrexed-based chemotherapy compared to those with ALK/ROS1 rearrangements, which strengthen the need for effective HER2-targeted drugs in clinical practice.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The steady increase in the incidence of obesity among adults has been paralleled with higher levels of obesity-associated breast cancer. While recent studies have suggested that adipose stromal/stem ...cells (ASCs) isolated from obese women enhance tumorigenicity, the mechanism(s) by which this occurs remains undefined. Evidence suggests that increased adiposity results in increased leptin secretion from adipose tissue, which has been shown to increased cancer cell proliferation. Previously, our group demonstrated that ASCs isolated from obese women (obASCs) also express higher levels of leptin relative to ASCs isolated from lean women (lnASCs) and that this obASC-derived leptin may account for enhanced breast cancer cell growth. The current study investigates the impact of inhibiting leptin expression in lnASCs and obASCs on breast cancer cell (BCC) growth and progression.
Estrogen receptor positive (ER+) BCCs were co-cultured with leptin shRNA lnASCs or leptin shRNA obASCs and changes in the proliferation, migration, invasion, and gene expression of BCCs were investigated. To assess the direct impact of leptin inhibition in obASCs on BCC proliferation, MCF7 cells were injected alone or mixed with control shRNA obASCs or leptin shRNA obASCs into SCID/beige mice.
ER+ BCCs were responsive to obASCs during direct co-culture, whereas lnASCs were unable to increase ER(+) BCC growth. shRNA silencing of leptin in obASCs negated the enhanced proliferative effects of obASC on BCCs following direct co-culture. BCCs co-cultured with obASCs demonstrated enhanced expression of epithelial-to-mesenchymal transition (EMT) and metastasis genes (SERPINE1, MMP-2, and IL-6), while BCCs co-cultured with leptin shRNA obASCs did not display similar levels of gene induction. Knockdown of leptin significantly reduced tumor volume and decreased the number of metastatic lesions to the lung and liver. These results correlated with reduced expression of both SERPINE1 and MMP-2 in tumors formed with MCF7 cells mixed with leptin shRNA obASCs, when compared to tumors formed with MCF7 cells mixed with control shRNA obASCs.
This study provides mechanistic insight as to how obesity enhances the proliferation and metastasis of breast cancer cells; specifically, obASC-derived leptin contributes to the aggressiveness of breast cancer in obese women.
Background
Excess body weight has been associated with worsening breast cancer survival. While bariatric surgery has been associated with less incident of breast cancer, the role that bariatric ...surgery plays after breast cancer diagnosis in terms of both feasibility and in preventing breast cancer recurrence is unclear.
Methods
We report the outcomes of 13 individuals who underwent bariatric surgery after definitive breast cancer treatment at a single institution.
Results
Thirteen females diagnosed with breast cancer (69.2% stage I, 23.1% stage II) at a median age of 42 years received bariatric surgery between 2001 and 2017. The median age of bariatric surgery was 52 years. Of the 13 patients, 46.2% underwent laparoscopic Roux-en-Y gastric bypass and 38.5% laparoscopic sleeve gastrectomy. The median time from breast cancer treatment to bariatric surgery was 3 years. The procedures were well tolerated. One female developed an abdominal wall hematoma. The average weight loss after 1 year and 2 years was 28.1% and 28.2%, respectively. There was a single breast cancer recurrence with a median follow-up of 11.7 years after breast cancer diagnosis and 5.3 years after bariatric surgery.
Conclusions
Bariatric surgery after breast cancer treatment is feasible and well tolerated. Prospective trials evaluating bariatric surgery in obese breast cancer survivors should be considered.
Purpose
The impact of an increased body mass index (BMI) on outcomes of neoadjuvant chemotherapy (NACT) in breast cancer remains controversial. The purpose of this study was to analyze the impact of ...BMI on pathological complete response (pCR) rates for operable breast cancer after NACT.
Methods
We searched Medline, Embase, and Web of Science database for observational studies and randomized controlled trials that reported the association of BMI with pCR after NACT. We performed a meta-analysis to assess the impact of BMI on pCR rate.
Results
We identified 13 studies including a total of 18,702 women with operable breast cancer who underwent NACT. Two studies were pooled analyses of prospective clinical trials (10,669 patients); the rest were case–control studies (8033 patients). All studies provided data of two BMI groups (BMI < 25 vs. BMI ≥ 25). Pooled analyses demonstrated that overweight/obese women were less likely to achieve pCR after NACT as compared to under-/normal weight women (odds ratio (OR) = 0.80; 95% confidence interval (CI): 0.68–0.93). Eleven studies provided data of three BMI groups (BMI < 25, 25 ≤ BMI < 30, BMI ≥ 30). Based on pooled analyses, both overweight and obese groups were less likely to achieve pCR with NACT as compared to under-/normal weight group, (OR = 0.77, 95% CI 0.65–0.93 and OR = 0.68, 95% CI 0.61–0.77, respectively).
Conclusions
Overweight and obese breast cancer patients had a lower pCR rate with NACT compared to patients with under-/normal weight. Further prospective studies may help confirm this finding and investigate possible mechanisms.
Aphids are one of the main pests of cotton and have been an important disaster limiting cotton yield. It is important to use satellite multispectral data to monitor the severity of cotton aphids in a ...timely and accurate manner on regional scale. Based on the combination of derivative of ratio spectra (DRS) and random forest (RF) algorithm, this study researched the quantitative monitoring model of cotton aphid severity based on Sentinel-2 data. First, the cotton area was extracted by using a supervised classification algorithm and the vegetation index threshold method. Then, the DRS algorithm was used to analyze the spectral characteristics of cotton aphids from three scales, and the Pearson correlation analysis algorithm was used to extract the bands significantly related to aphid infestation. Finally, the RF model was trained by ground sampling points and its accuracy was evaluated. The optimal model results were selected by the cross-validation method, and the accuracy was compared with the four classical classification algorithms. The results showed that (1) the canopy spectral reflectance curves at different grades of cotton aphid infestation were significantly different, with a significant positive correlation between cotton aphid grade and spectral reflectance in the visible band range and a negative correlation in the near-infrared band range; (2) The DRS algorithm could effectively remove the interference of the background endmember of satellite multispectral image pixels and enhance the aphid spectral features. The analysis results from three different scales and the evaluation results demonstrate the effectiveness of the algorithm in processing satellite multispectral data; (3) After the DRS processing, Sentinel-2 multispectral images could effectively classify the severity of cotton aphid infestation by the RF model with an overall classification accuracy of 80% and a kappa coefficient of 0.73. Compared with the results of four classical classification algorithms, the proposed algorithm has the best accuracy, which proves the superiority of RF. Based on satellite multispectral data, the DRS and RF can be combined to monitor the severity of cotton aphids on a regional scale, and the accuracy can meet the actual need.
Key message
CCA1α and CCA1β protein variants respond to environmental light and temperature cues, and higher temperature promotes CCA1β protein production and causes its retention detectable in the ...cytoplasm.
CIRCADIAN CLOCK ASSOCIATED1 (CCA1), as the core transcription factor of circadian clock, is involved in the regulation of endogenous circadian rhythm in
Arabidopsis
. Previous studies have shown that
CCA1
consists of two abundant splice variants, fully spliced
CCA1α
and intron-retaining
CCA1β
. CCA1β is believed to form a nonfunctional heterodimer with CCA1α and its closed-related homolog LHY. Many studies have established that
CCA1β
is a transcription product, while how CCA1β protein is produced and how two CCA1 isoforms respond to environmental cues have not been elucidated. In this study, we identified CCA1α and CCA1β protein variants under different photoperiods with warm or cold temperature cycles, respectively. Our results showed that CCA1 protein production is regulated by prolonged light exposure and warm temperature. The protein levels of CCA1α and CCA1β peak in the morning, but the detection of CCA1β is dependent on immunoprecipitation enrichment at 22 °C. Higher temperature of 37 °C promotes CCA1β protein production and causes its retention to be detectable in the cytoplasm. Overall, our results indicate that two splice variants of the CCA1 protein respond to environmental light and temperature signals and may, therefore, maintain the circadian rhythms and give individuals the ability to adapt to environment.