[Bacterial Community Structure of Typical Lake Sediments in Yinchuan City and Its Response to Heavy Metals].

Lake wetlands are extremely important and special ecosystems, which are important for regional water resource storage, environmental protection, and biodiversity maintenance. Sediment bacteria are an important component of lake ecosystems and are a major driver of biogeochemical cycling in lakes. In order to investigate the community structure of bacteria in typical lake sediments in Yinchuan City and their influencing factors, three typical lakes in Yinchuan City (Yuehai Lake, Mingcui Lake, and Xiniu Lake) were selected for the study and surface sediments were collected in January, April, July, and October 2021. The composition of the sediment bacterial community was examined using 16S rDNA high-throughput sequencing technology, and the response relationships between them and heavy metals were explored. The results showed that the ecological hazard coefficient for heavy metals in the sediments of three typical lakes in Yinchuan City was far less than 40, and the ecological hazard index was far less than 150, all of which indicated a minor ecological hazard. There were no significant differences in bacterial community diversity among the three lakes, but there were significant variations in diversity among the lakes in different seasons and significant differences in community composition. The dominant phyla (top three in terms of relative abundance) in Yuehai Lake, Mingcui Lake, and Xiniu Lake were Proteobacteria, Bacteroidetes, and Chloroflexi. The dominant lower orders were Gammaproteobacteria, Alphaproteobacteria, and Deltaproteobacteria. The main divergent species that occurred at the phylum level in typical lakes in Yinchuan were Proteobacteria, Bacteroidetes, Euryarchaeota, Firmicutes, Actinobacteria, and Acidobacteria. The sediment bacterial community structure of Yuehai Lake was significantly correlated with Cu, Fe, Mn, Zn, As, and Pb; the sediment bacterial community structure of Lake Mingcui was significantly correlated with Fe, Pb, and Cr; and the sediment bacterial community structure of Xiniu Lake was not significantly correlated with heavy metals. The types and contents of sediment heavy metals had a significant effect on the bacterial community structure of sediments in Yinchuan Yuehai Lake and Mingcui Lake and were important environmental factors that caused changes in the bacterial community structure of lake sediments.

Yiqi formula enhances the antitumor effects of erlotinib for treatment of triple-negative breast cancer xenografts.

Yiqi formula (YF), a traditional herbal prescription, has long been used to treat triple-negative breast cancer (TNBC) patients. The present study aims to investigate the effects and the related mechanism of YF for treatment of TNBC xenografts. MDA-MB-231 (human TNBC) cells were subcutaneously injected into the second mammary fat pad of 40 female nude mice, which were divided into four groups: control, erlotinib (an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor), YF, and combination (YF plus erlotinib). All treatments were administered orally for 30 days. Inhibition rate of tumor weight by erlotinib, YF, and the combination was 26.47%, 17.24%, and 39.15%, respectively. Western blotting showed that YF, erlotinib, and the combination downregulated p-EGFR (P < 0.01) and p-Akt1 (pT308) (P < 0.05) and upregulated PTEN compared with control, and the combination was more efficacious than erlotinib alone (P < 0.05). Similar results were detected by immunohistochemistry. Real-time quantitative PCR showed that YF, erlotinib, and the combination increased PTEN mRNA (P < 0.05, P < 0.01) compared with control, and the combination was more efficacious than erlotinib alone (P < 0.05). In conclusion, YF can regulate the main components of the PI3K/Akt pathway in TNBC xenografts. When YF was used in combination with erlotinib, it enhanced the antitumor effects of erlotinib on TNBC xenografts. These findings suggest that YF is suitable to use for the treatment of TNBC patients.

[Expression and significance of immunoglobulin free light chains in serum and lung tissues from patients with chronic obstructive pulmonary disease].

OBJECTIVE: To study the association of free immunoglobulin light chain (FLC) with clinical manifestations and lung inflammation in smokers with normal lung function and chronic obstructive pulmonary disease (COPD) patients. METHODS: Thirty-two patients with peripheral lung cancer undergoing surgical resection were enrolled from the Department of Thoracic Surgery,Affiliated Hospital of Xuzhou Medical College. They were divided into non-smoking with normal lung function group (non-smoking group, 10 cases), smoking with normal lung function group (smoking group, 12 cases) and smoking with stable COPD group (COPD group, 10 cases). Their preoperative fasting serum and lung tissues away from cancer were used in the study.Enzyme-linked immunesorbent assays (ELISA) were used to detect the levels of FLC-λ and FLC-κ in serum and lung tissue homogenates. The expression of FLC-λ and FLC-κ in the airway epithelium, alveolar wall and blood vessel wall was detected by immunohistochemistry. The correlation between FLC levels and pulmonary functions were analyzed. RESULTS: The serum levels of FLC-λ and FLC-κ in COPD group and smoking group were (35 ± 11),(38 ± 12) and (26 ± 9),(26 ± 8) mg/L, respectively. They were all significantly increased compared with the non-smoking group [(16 ± 7),(16 ± 5) mg/L]. The differences were all statistically significant (q = 3.590-7.482, P < 0.01), and those of the COPD group were significantly higher than those of the smoking group (q = 3.209-4.198, P < 0.05 and P < 0.01). The concentrations of FLC-λ and FLC-κ in lung tissue homogenates of the COPD group and the smoking group were (1.29 ± 0.31),(1.32 ± 0.30) and (0.86 ± 0.42),(0.85 ± 0.37) µg/mg, respectively. They were all significantly increased compared with those of the non-smoking group [(0.45 ± 0.18),(0.42 ± 0.13) µg/mg],(q = 4.178- 9.795, P < 0.05 and P < 0.01). The levels of FLC-λ and FLC-κ in the lung tissue homogenates from the COPD group were significantly higher than those from the smoking group (q = 4.269-4.349, all P < 0.05). The expression of FLC-λ and FLC-κ was detected in airway epithelium, alveolar wall and blood vessel wall. The levels of FLC-λ and FLC-κ in serum and lung tissue homogenates showed a negative correlation with FEV1 percentage of predicted value (r = -0.476 to -0.591, all P < 0.01). CONCLUSIONS: Expressions of FLC were increased in the serum and the lung tissues of COPD patients and smokers with normal lung function, and closely correlated with airflow limitation. The results suggest that FLC plays a proinflammatory role in the pathogenesis of COPD.

[Effects of Astragalus polysaccharide on proliferation and Akt phosphorylation of the basal-like breast cancer cell line].

OBJECTIVE: To investigate the effects of Astragalus polysaccharide (APS) on proliferation of basal-like breast cancer cell line MDA-MB-468 cells and Akt phosphorylation in MDA-MB-468 cells. METHODS: APS at different concentrations was used to culture MDA-MB-468 cells for different time periods, and then proliferation of MDA-MB-468 cells was assayed using methyl thiazolyl tetrazolium (MTT) assay to determine the time- and dose-dependent effects of APS. For observing the effects of APS on phosphor-Akt (p-Akt), in-cell Western blot method was used after 1, 2, 4 and 7 d of culture in APS to detect protein expressions of p-Akt (Thr308) and p-Akt (Ser473). Protein levels of the key targets in p53/murine double minute 2 (MDM2) signaling pathway, such as p53, MDM2 and phosphatase and tensin homolog deleted on chromosome ten (PTEN) were also detected. After PTEN gene was silenced by small interfering RNA (siRNA) in MDA-MB-468 cells, expressions of p-Akt (Thr308 and Ser473) were assayed by the in-cell Western blot method after 2 d of APS treatment. RESULTS: APS at 1 and 0.5 mg/mL concentrations effectively inhibited the proliferation of MDA-MB-468 cells and was used in subsequent tests. Compared with the control group, APS decreased the protein expression of p-Akt (Thr308) in MDA-MB-468 cells after 1-, 2-, 4- and 7-day culture, and also decreased the protein expression of p-Akt (Ser473) and up-regulated the protein expression of MDM2 in MDA-MB-468 cells after 1- and 2-day culture. Expressions of p53 and PTEN were up-regulated after 7 d of APS culture. After silencing PTEN gene by siRNA, APS could not mediate Akt phosphorylation. CONCLUSION: APS can inhibit proliferation of basal-like breast cancer cell line MDA-MB-468, and down-regulate the expression of Akt phosphorylation. The antiproliferation mechanisms may be related to its effects of up-regulating the expressions of p53 and PTEN by regulating p53/MDM2 positive and negative feedback loops.