Passivation agent with dipole moment for surface modification towards efficient and stable perovskite solar cells

Recently, there has been renewed interest in interface engineering as a means to further push the performance of perovskite solar cells closer to the Schockly-Queisser limit. Herein, for the first time we employ a multi-functional 4-chlorobenzoic acid to produce a self-assembled monolayer on a perovskite surface. With this interlayer we observe passivation of perovskite surface defects and a significant suppression of non-radiative charge recombination. Furthermore, at the surface of the interlayer we observe, charge dipoles which tune the energy level alignment, enabling a larger energetic driving force for hole extraction. The perovskite surface becomes more hydrophilic due to the presence of the interlayer. Consequently, we observe an improvement in open-circuit voltage from 1.08 to 1.16 V, a power conversion efficiency improvement from 18% to 21% and an improved stability under ambient conditions. Our work highlights the potential of SAMs to engineer the photo-electronic properties and stability of perovskite interfaces to achieve high-performance light harvesting devices

Metformin inhibited esophageal squamous cell carcinoma proliferation in vitro and in vivo and enhanced the anti-cancer effect of cisplatin.

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignancy with poor prognosis in China. Chemotherapy now is one of the most frequently used treatments for patients with ESCC in middle or late stage, however the effects were often limited by increased chemoresistance or treatment toxicity. So it is urgent to find new drugs to treat ESCC patients. Metformin with low cost and toxicity has proved to have anti-cancer effects in a numerous cancers, while its role and mechanism in ESCC has seldom been studied. In the present study, we found that metformin exhibited not only an anti-proliferation ability in a dose and time dependent manner but also a proapoptosis effect in a dose dependent manner in ESCC cell line KYSE450. Our in vivo experiment also showed that metformin markedly inhibited KYSE450 xenograft tumors growth compared to those treated with normal saline. What's more, no obvious toxic reactions were observed. To further explore the underlying mechanism, we found that metformin treatment could significantly damp the expression of 4EBP1 and S6K1 in KYSE 450 cells in vitro and in vivo, furthermore, the p-4EBP1 and p-S6K1 expression in KYSE 450 cells were also inhibited greatly in vitro and in vivo. During the therapy of cancer, in order to overcome side effects, combination therapy was often used. In this paper, we demonstrated that metformin potentiated the effects of cisplatin via inhibiting cell proliferation and promoting cell apoptosis. Taken together, metformin owned the potential anti-cancer effect on ESCC in monotherapy or was combined with cisplatin and these results laid solid basis for the use of metformin in ESCC

Prognostic Significance of Tumor-infiltrating CD8 + or CD3 + T Lymphocytes and Interleukin-2 Expression in Radically Resected Non-small Cell Lung Cancer

Background: Altered immunoresponse is associated with tumorigenesis and cancer progression. This study assessed the levels of tumor-infiltrating CD3 + or CD8 + T lymphocytes and interleukin-2 (IL-2) protein in radically resected non-small cell lung cancer (NSCLC) tissues to predict overall survival (OS) of the patients. Methods: Paraffin-embedded tissue specimens from 129 NSCLC patients were retrospectively collected for immunostaining of CD8 + , CD3 + , and IL-2 expression. Clinicopathological and survival data were collected and analyzed using the Chi-squared test, Kaplan-Meier curves, and the log-rank test or the Cox regression model. Results: The data showed a significant inverse association between CD8 + T lymphocyte levels and IL-2 expression (r = −0.927; P = 0.000) and between the levels of CD8 + and CD3 + T lymphocytes (r = −0.722; P = 0.000), but a positive association between CD3 + T lymphocyte levels and IL-2 expression (r = 0.781; P = 0.000) in NSCLC tissues. Furthermore, the levels of CD3 + and CD8 + T lymphocytes and IL-2 expression were associated with tumor stage (P = 0.023, 0.006, and 0.031, respectively) and the level of CD8 + T lymphocytes was associated with the patient gender (P = 0.024). In addition, the levels of CD8 + T lymphocytes were associated with an unfavorable 5-year OS, whereas patients with high levels of CD3 + T lymphocytes in tumor lesions and IL-2-expressing tumors had significantly better 5-year OS rates than patients with low levels. Conclusions: The levels of CD8 + T cells in tumor lesions and IL-2 expression were both independent predictors of OS for these NSCLC patients. Thus, the detection of tumor-infiltrating CD3 + or CD8 + T lymphocytes and IL-2 expression could be useful to predict the prognosis of radically resected NSCLC patients

Assessing the changes in childbirth care practices and neonatal outcomes in Western China: pre-comparison and post-comparison study on early essential newborn care interventions

Objective To explore the changes in childbirth care practices and health outcomes of newborns after the introduction of early essential newborn care (EENC).Design A pre-comparison and post-comparison study.Setting The study was conducted in December 2016 and December 2018 in 18 counties in four western provinces of China.Participants 46 hospitals that provide delivery services participated in the study.Interventions EENC practices were introduced and implemented in the 46 hospitals.Outcome measures The changes of hospital indicators such as incidence of birth asphyxia and neonatal mortality were compared in 2016 and 2018. EENC coverage indicators, such as skin-to-skin (STS) contact, and time of first breast feeding were also compared before and after the intervention via interview with 524 randomly selected postpartum mothers (320 in 2016 and 204 in 2018).Results 54 335 newborns were delivered in the pre-EENC period (2016) and 58 057 delivered in the post-EENC period (2018). According to hospital records, the proportion of newborns receiving immediate STS contact increased from 32.6% to 51.2% (Risk Ratio (RR)=1.57,95% CI 1.55 to 1.59) and the percentage of newborns receiving prolonged STS contact for more than 90 min increased from 8.1% to 26.8% (RR=3.31, 95% CI 3.21 to 3.41). No statistically significant changes were found in neonatal mortality, although slight decreases in birth asphyxiate and neonatal intensive care unit admission rates were detected. Among the mothers interviewed, the proportion of newborns receiving immediate STS contact increased from 34.6% to 80.0% (RR=2.31, 95% CI 1.69 to 3.17). The exclusive breastfeeding rate increased from 43% to 73.4% (RR=1.71, 95% CI 1.43 to 2.04). The average length of the first breast feeding increased from 15.8 min to 17.1 min.Conclusions The introduction of EENC has yielded significant improvements in newborn care services at the pilot hospitals, including enhanced maternal and newborn care practices, improved STS contact quality and early breastfeeding performance. Further studies are needed to evaluate the long-term impact of EENC on newborn health outcomes

The effect of antibiotic prophylaxis on the incidence of surgical site infection after laparoscopic appendectomy for chronic appendicitis

Background: The guidelinesthat specify whether antibiotic prophylaxis should be administered before laparoscopic clean-contaminated wound to prevent postoperative surgical site infection (SSI) need to be improved. Studies have shown that elective laparoscopic cholecystectomy with clean-contaminated wound does not require antibiotic prophylaxis. However, there are no studies on the effect of antibiotic prophylaxis on SSI after laparoscopic appendectomy for chronic appendicitis (LCA), which is a clean-contaminated wound. Methods: We conducted a single-center, double-blind, randomized controlled clinical trial. A total of 106 effective patients were randomly divided into the antibiotic group and saline group. Cefuroxime or clindamycin was administered intravenously in the antibiotic group (n = 52). Saline (0.9%) was administered intravenously in the saline group (n = 54). Interventions were administered as a single dose 30 min before surgery. Results: Among the 106 effective patients (median age, 37 years old [IQR, 25–45]; females, 77 [72.6%]), there were 6 cases (5.70%) of SSI: 3 cases (5.56%) in the saline group and 3 cases (5.70%) in the antibiotic group (OR = 1.00, [95% CI (0.20–5.4)], P = 0.96). There were no significant differences in the clinical outcomes of anal exhaust time, postoperative complications, and the symptom of primary abdominal pain between the two groups. Conclusion: For patients with chronic appendicitis undergoing laparoscopic appendectomy, preoperative intravenous antibiotic prophylaxis did not reduce the risk of SSI within 30 days of the surgery compared to the saline group. Trial registration: Registration number of China Clinical Trials Registration Center: ChiCTR2100048336

Metformin inhibited 4EBP1 and S6K1 expression in vivo.

<p>Xenograft tumors were harvested, fixed and paraffin-embedded, and stained for 4EBP1, S6K1, p-4EBP1 and p- S6K1 by immunohistochemistry. The protein expression of 4EBP1 and S6K1 were mainly located in the nuclear and cytoplasm of the KYSE450 cells. Immunohistochemical examination exhibited decreased average density of stain for 4EBP1 and S6K1 in metformin treated group than those in control group. The protein expression of p-4EBP1 and p-S6K1 were mainly located in the nuclear of the KYSE450 cells. And the immunohistochemical examination exhibited decreased average density of stain for p-4EBP1 and p-S6K1 in metformin treated group than those in control group. <b>A.</b> The protein expression of 4EBP1 in metformin group (a) and control group (b). <b>B.</b> The protein expression of S6K1 in metformin group (a) and control group (b). <b>C.</b> The protein expression of p-4EBP1 in metformin group (a) and control group (b). <b>D.</b> The protein expression of p-S6K1 in metformin group (a) and control group (b).</p

Metformin treatment inhibited the expression of 4EBP1 and S6K1.

<p><b>A</b>. KYSE 450 cells were treated with 5, 10, 20 mmol/L of metformin for 48h. RT-PCR and western blot results showed that with the increase of concentration, the mRNA and protein expression of 4EBP1and S6K1 decreased significantly compared to those untreated KYSE 450 cells. Furthermore the protein expression of phosphorylated form of 4EBP1 and S6K1 were also inhibited by metformin in a dose dependent manner. <b>B.</b> KYSE 450 cells were treated with 20 mmol/L of metformin for 24, 48 and 72h respectively. RT-PCR and western blot results showed that with the extension of time, the mRNA and protein expression of 4EBP1and S6K1 also decrease greatly compared to those untreated KYSE 450 cells. In addition, the the protein expression of phosphorylated form of 4EBP1 and S6K1 were also inhibited by 20 mmol/L metformin in a time dependent manner. *P < 0.05 denoted a great different effects of different concentrations, different time of metformin on the 4EBP1 and S6K1 mRNA, protein or phosphorylated form of protein expression for esophageal cancer cells KYSE450.</p

The combination effects of metformin and cisplatin on the proliferation and apoptosis ability of KYSE 450 cells.

<p>A. KYSE 450 cells treated with 5, 10, 20 and 40mmol/L metformin combined with 10ug/ml cisplatin for 24, 48h and cell proliferation was measured by MTT assay. The results showed that metformin enhanced the inhibition rate of cisplatin on the proliferation of KYSE450 cells. Furthermore, the inhibition rate increased with the increase of the concentration of metformin. *P<0.01 or **P<0.05 denotes a significant difference between different concentration at the same time point; ***P<0.05 denoted a significant difference between different time point at the same concentration. B. Annexin V-FITC/PI was used to analyze of apoptosis ability of KYSE 450 cells treated with 0, 5, 10 and 20 mmol/L metformin and cisplatin(10ug/mL) at the same time. The results demonstrated that metformin could also improve the apoptosis caused by cisplatin and the percentage of apoptotic cells increased with the rising concentration of metformin. **P<0.05 denoted a significant difference between different concentration.</p

Effects of metformin on the proliferation and apoptosis ability of KYSE 450 cells.

<p>A. KYSE 450 cells treated with 5, 10, 20 and 40mmol/L metformin for 24, 48, 72h and cell proliferation was measured by MTT assay. The results revealed that the inhibition rate of the proliferation ability of KYSE 450 cells increased significantly with the time going and concentration rising. *P<0.01 denotes a significant difference between different concentration at the same time point; **P<0.05 denoted a significant difference between different time point at the same concentration. B. Annexin V-FITC/PI was used to analyze of apoptosis ability of KYSE 450 cells treated with 0, 5, 10 and 20 mmol/L metformin. With the increase of concentration, the percentage of apoptotic cells improved markedly. a was the control group, b-d were the group of 5, 10, 20 mmol/L metformin respectively. **P<0.05 denoted a significant difference between different concentration.</p