Hominin occupation of the Chinese Loess Plateau since about 2.1 million years ago.

Considerable attention has been paid to dating the earliest appearance of hominins outside Africa. The earliest skeletal and artefactual evidence for the genus Homo in Asia currently comes from Dmanisi, Georgia, and is dated to approximately 1.77-1.85 million years ago (Ma)1. Two incisors that may belong to Homo erectus come from Yuanmou, south China, and are dated to 1.7 Ma2; the next-oldest evidence is an H. erectus cranium from Lantian (Gongwangling)-which has recently been dated to 1.63 Ma3-and the earliest hominin fossils from the Sangiran dome in Java, which are dated to about 1.5-1.6 Ma4. Artefacts from Majuangou III5 and Shangshazui6 in the Nihewan basin, north China, have also been dated to 1.6-1.7 Ma. Here we report an Early Pleistocene and largely continuous artefact sequence from Shangchen, which is a newly discovered Palaeolithic locality of the southern Chinese Loess Plateau, near Gongwangling in Lantian county. The site contains 17 artefact layers that extend from palaeosol S15-dated to approximately 1.26 Ma-to loess L28, which we date to about 2.12 Ma. This discovery implies that hominins left Africa earlier than indicated by the evidence from Dmanisi.

Protective effects of methylprednisolone-cyclophosphamide treatment on bleomycin-induced pulmonary fibrosis.

BACKGROUND: Methylprednisolone (MP) and cyclophosphamide (CTX) combination treatment has shown great benefits in improving pulmonary fibrosis (PF) and high safety. Currently, the mechanism underlying the effects of MP-CTX on improving PF remains unclear. This study determined the effects of MP-CTX combination treatment on the modulation of inflammation, oxidative stress, and T-cell immunity in PF. METHODS: PF rat models were induced by bleomycin stimulation. MP (3 mg/kg) and MP-CTX (MP: 3 mg/kg; CTX: 8 mg/kg) combination were administered in the PF + MP and PF + MP + CTX groups, respectively. Transmission electron microscopy, hematoxylin and eosin staining, Ashcroft score, and Masson trichrome staining were performed to measure lung morphology in PF. Enzyme-linked immunosorbent assay and quantitative polymerase chain reaction assay were performed to quantify inflammatory factors. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX) levels were determined using commercial kits. α-Smooth muscle actin (SMA) and collagen I levels were determined using western blotting and immunohistochemistry. The T-cell count was evaluated using flow cytometry. RESULTS: MP-CTX reduced lung injury, collagen deposition, and α-SMA and collagen I levels in a bleomycin-induced PF rat model. Additionally, MP-CTX decreased the levels of MDA and inflammatory factors (tumor necrosis factor-α, interleukin-1ß, and interleukin-6) but increased the activities of SOD and GSH-PX. Furthermore, MP-CTX changed T-cell types in lung tissues, such as increasing CD4+CD25+Foxp3+ cell count. CONCLUSIONS: MP-CTX combination treatment improved the degree of PF by reducing inflammation and oxidative stress and improving T-cell immunity. These findings provide novel insights into the mechanisms underlying the effects of MP-CTX on PF.

Individualized model for predicting COVID-19 deterioration in patients with cancer: A multicenter retrospective study.

The 2019 novel coronavirus has spread rapidly around the world. Cancer patients seem to be more susceptible to infection and disease deterioration, but the factors affecting the deterioration remain unclear. We aimed to develop an individualized model for prediction of coronavirus disease (COVID-19) deterioration in cancer patients. The clinical data of 276 cancer patients diagnosed with COVID-19 in 33 designated hospitals of Hubei, China from December 21, 2019 to March 18, 2020, were collected and randomly divided into a training and a validation cohort by a ratio of 2:1. Cox stepwise regression analysis was carried out to select prognostic factors. The prediction model was developed in the training cohort. The predictive accuracy of the model was quantified by C-index and time-dependent area under the receiver operating characteristic curve (t-AUC). Internal validation was assessed by the validation cohort. Risk stratification based on the model was carried out. Decision curve analysis (DCA) were used to evaluate the clinical usefulness of the model. We found age, cancer type, computed tomography baseline image features (ground glass opacity and consolidation), laboratory findings (lymphocyte count, serum levels of C-reactive protein, aspartate aminotransferase, direct bilirubin, urea, and d-dimer) were significantly associated with symptomatic deterioration. The C-index of the model was 0.755 in the training cohort and 0.779 in the validation cohort. The t-AUC values were above 0.7 within 8 weeks both in the training and validation cohorts. Patients were divided into two risk groups based on the nomogram: low-risk (total points ≤ 9.98) and high-risk (total points > 9.98) group. The Kaplan-Meier deterioration-free survival of COVID-19 curves presented significant discrimination between the two risk groups in both training and validation cohorts. The model indicated good clinical applicability by DCA curves. This study presents an individualized nomogram model to individually predict the possibility of symptomatic deterioration of COVID-19 in patients with cancer.

Association between recent oncologic treatment and mortality among patients with carcinoma who are hospitalized with COVID-19: A multicenter study.

BACKGROUND: To the authors' knowledge, little is known regarding the association between recent oncologic treatment and mortality in patients with cancer who are infected with coronavirus disease 2019 (COVID-19). The objective of the current study was to determine whether recent oncologic treatment is associated with a higher risk of death among patients with carcinoma who are hospitalized with COVID-19. METHODS: Data regarding 248 consecutive patients with carcinoma who were hospitalized with COVID-19 were collected retrospectively from 33 hospitals in Hubei Province, China, from January 1, 2020, to March 25, 2020. The follow-up cutoff date was July 22, 2020. Univariable and multivariable logistic regression analyses were performed to identify variables associated with a higher risk of death. RESULTS: Of the 248 patients enrolled, the median age was 63 years and 128 patients (52%) were male. On admission, 147 patients (59%) did not undergo recent oncologic treatment, whereas 32 patients (13%), 25 patients (10%), 12 patients (5%), and 10 patients (4%), respectively, underwent chemotherapy, surgery, targeted therapy, and radiotherapy. At the time of last follow-up, 51 patients (21%) were critically ill during hospitalization, 40 of whom had died. Compared with patients without receipt of recent oncologic treatment, the mortality rate of patients who recently received oncologic treatment was significantly higher (24.8% vs 10.2%; hazard ratio, 2.010 [95% CI, 1.079-3.747; P = .027]). After controlling for confounders, recent receipt of chemotherapy (odds ratio [OR], 7.495; 95% CI, 1.398-34.187 [P = .015]), surgery (OR, 8.239; 95% CI, 1.637-41.955 [P = .012]), and radiotherapy (OR, 15.213; 95% CI, 2.091-110.691 [P = .007]) were identified as independently associated with a higher risk of death. CONCLUSIONS: The results of the current study demonstrated a possible association between recent receipt of oncologic treatment and a higher risk of death among patients with carcinoma who are hospitalized with COVID-19.

Advantages with prophylactic PEG-rhG-CSF versus rhG-CSF in breast cancer patients receiving multiple cycles of myelosuppressive chemotherapy: an open-label, randomized, multicenter phase III study.

BACKGROUND: PEG-rhG-CSF reduces neutropenia and improves chemotherapy safety. In China's registration trial (CFDA: 2006L01305), we assessed its efficacy and safety against rhG-CSF, and prospectively explored its value over multiple cycles of chemotherapy. METHODS: In this open-label, randomized, multicenter phase 3 study, breast cancer patients (n = 569) were randomized to receive PEG-rhG-CSF 100 µg/kg, PEG-rhG-CSF 6 mg, or rhG-CSF 5 µg/kg/d after chemotherapy. The primary endpoints were the incidence and duration of grade 3/4 neutropenia during cycle 1. Secondary endpoints included the incidence and duration of grade 3/4 neutropenia during cycles 2-4, the incidence of febrile neutropenia, and the safety. RESULTS: A once-per-cycle PEG-rhG-CSF at either 100 µg/kg or 6 mg was not different from daily injections of rhG-CSF for either incidence or duration of grade 3/4 neutropenia. Interestingly, a substantial difference was noted during cycle 2, and the difference became bigger over cycles 3-4, reaching a statistical significance at cycle 4 in either incidence (P = 0.0309) or duration (P = 0.0289) favoring PEG-rhG-CSF. A significant trend toward a lower incidence of all-grade adverse events was noted at 129 (68.98%), 142 (75.53%), and 160 (82.47%) in the PEG-rhG-CSF 100 µg/kg and 6 mg and rhG-CSF groups, respectively (P = 0.0085). The corresponding incidence of grade 3/4 drug-related adverse events was 2/187 (1.07%), 1/188 (0.53%), and 8/194 (4.12%), respectively (P = 0.0477). Additionally, PFS in metastatic patients preferred PEG-rhG-CSF to rhG-CSF despite no significance observed by Kaplan-Meier analysis (n = 49, P = 0.153). CONCLUSIONS: PEG-rhG-CSF is a more convenient and safe formulation and a more effective prophylactic measure in breast cancer patients receiving multiple cycles of chemotherapy.

New dating of the Homo erectus cranium from Lantian (Gongwangling), China.

The Homo erectus cranium from Gongwangling, Lantian County, Shaanxi Province is the oldest fossil hominin specimen from North China. It was found in 1964 in a layer below the Jaramillo subchron and was attributed to loess (L) L15 in the Chinese loess-palaeosol sequence, with an estimated age of ca. 1.15 Ma (millions of years ago). Here, we demonstrate that there is a stratigraphical hiatus in the Gongwangling section immediately below loess 15, and the cranium in fact lies in palaeosol (S) S22 or S23, the age of which is ca. 1.54-1.65 Ma. Closely spaced palaeomagnetic sampling at two sections at Gongwangling and one at Jiacun, 10 km to the north, indicate that the fossil layer at Gongwangling and a similar fossil horizon at Jiacun were deposited shortly before a short period of normal polarity above the Olduvai subchron. This is attributed to the Gilsa Event that has been dated elsewhere to ca. 1.62 Ma. Our investigations thus demonstrate that the Gongwangling cranium is slightly older than ca. 1.62 Ma, probably ca. 1.63 Ma, and significantly older than previously supposed. This re-dating now makes Gongwangling the second oldest site outside Africa (after Dmanisi) with cranial remains, and causes substantial re-adjustment in the early fossil hominin record in Eurasia.

Matrix metalloproteinase-9 overexpression is closely related to poor prognosis in patients with colon cancer.

BACKGROUND: Matrix metalloproteinase-9 (MMP-9) is an important member of the matrix metalloproteinase family and is considered to be involved in the invasion and metastasis of cancer cells. This study analyzed the expression of MMP-9 in colon cancer patients and the relationship between this expression and clinicopathological features and survival. METHODS: We immunohistochemically investigated 68 specimens of colon cancer tissues and corresponding distal normal mucosa tissues using MMP-9 antibody. Then, the correlation between MMP-9 expression and clinicopathological features and its prognostic relevance were determined. RESULTS: The expression rate of MMP-9 in colon cancer tissues was significantly higher than that in distal normal mucosa (69.1% versus 2.9%, P < 0.001). Significant correlations were only found between high levels of MMP-9 expression and metastasis of lymph nodes and Dukes' stage. Overexpression of MMP-9 was associated with shorter survival times in univariate analysis. Multivariate analysis confirmed that MMP-9 expression was an independent prognostic factor. CONCLUSIONS: MMP-9 is correlated with the metastasis of lymph nodes, and its elevated expression may be an adverse prognostic indicator for the patients of colon cancer.

Comparative ultrastructure analysis of radiation-induced radioresistant laryngeal cancer hep-2 cell line.

Radioresistance is one of the main reasons for the failure of radiotherapy in laryngeal cancer. However, the mechanisms of radioresistance of tumor cells have remained elusive. This study was conducted to identify the ultrastructural changes of radiation-induced radioresistant laryngeal cancer hep-2 cell line. First, a radioresistant hep-2R cell line was generated after prolonged exposure to γ-rays for 60 Gy (6 Gy/day, 2 days/week) and was confirmed by clonogenic assay. Next, the ultrastructural differences between hep-2R cells and hep-2 cells were compared by transmission electron microscopy. Finally, the results showed that hep-2R cells showed significant resistance to radiation compared with parental hep-2 cells. Increased cell nucleus atypia, more rough endoplasmic reticulum and less mitochondria were observed in hep-2R cells. The amount of microvilli of hep-2R was similar to hep-2 cell. In summary, these ultrastructural differences revealed the morphological mechanism that hep-2R cells had stronger radioresistance than hep-2 cells.

Natural and anthropogenic controls on environmental change during the Holocene based on a multi-proxy record obtained from subalpine peatland in southern China.

The interactions between past climate, human activity and environmental change in subtropical mountainous areas are poorly understood due to the lack of reliable records in South China. In this study, the evolution of the East Asian summer monsoon (EASM) during the Holocene, and the interactions between regional human activity and environmental change, were studied using multi-proxy records from a subalpine peat core recovered from South China. The chronology of this peat core has been well-constrained by 10 AMS 14C dates of peat stems. A series of proxy indicators, including carbon isotopes (δ13C), loss on ignition (LOI), magnetic susceptibility (MS), the chemical index of alteration (CIA), and geochemical elements from the Shiwangutian (SWGT) peatland were used to reconstruct the palaeohydrological changes during the Holocene. Regional moisture levels showed a generally arid-wet-arid pattern, and three phases of climatic change were detected as follows. 1) Between 11,600 and 9000 cal yr BP, the EASM was weak and a relatively dry climate developed. 2) Between 9000 and 4000 cal yr BP, the prevalence of humid climatic conditions was associated with a strong summer monsoon. 3) After 4000 cal yr BP, the climate shifted to relatively dry conditions. Further comparisons and analysis suggested that solar insolation, migration of the Intertropical Convergence Zone (ITCZ), and El Niño-Southern Oscillation (ENSO) activity played an important role in determining the variations in Holocene EASM intensity. In addition, the increase in both MS and heavy metal concentrations over the last 1000 years is consistent with an increase in the population of Hunan Province. Therefore, it can be inferred that population growth and the associated expansion of cropland and mining led to an increase in soil erosion and metal tool use. These findings suggest that the impact of human activity generally outweighed the natural climatic controls on the environment and landscape in the mountainous region of southern China over the last 1000 years.

MiR-26a regulates cell cycle and anoikis of human esophageal adenocarcinoma cells through Rb1-E2F1 signaling pathway.

Resistance to anoikis, the subtype of apoptosis induced by lack of matrix adhesion, contributes to malignant transformation and development of metastasis. MicroRNAs play key regulatory roles in tumorigenesis and metastasis. In this study, we described that miR-26a, which is usually downregulated in tumor cells, is involved in the acquisition of anoikis-resistance of human esophageal adenocarcinoma (EA) cells. Results of qRT-PCR in clinical samples showed that downregulated miR-26a expression is related to tumorigenesis and metastasis of EA. In vitro experiments determined that miR-26a directly participates in the regulation of cell cycle and anoikis of human EA OE33 cells. Further, we identified that Rb1 is the direct functional target of miR-26a, and revealed that the reduction of miR-26a expression leads to increased Rb1 protein level and thus inhibits the function of E2F1, by which it influences the phenotypes of cell cycle and anoikis. The findings we reported here presented the evidence that miR-26a may be involved in regulation of anoikis-resistance of EA cells. Targeting miR-26a may provide a novel strategy to inhibit metastasis.

Clinicopathological significance and prognostic value of MMP-13 expression in colorectal cancer.

The purpose of this study was to evaluate the association of matrix metalloproteinase-13 (MMP-13) expression with clinicopathological features and prognosis in colorectal cancer (CRC) patients. CRC tissues and distal normal mucosa tissues of 158 CRC patients were detected by immunohistochemistry. The correlations between MMP-13 expression, the patients' clinicopathological features, and overall survival rate were analyzed. It was found that positive expression rate of MMP-13 in distal normal mucosa tissues was significantly lower than that in CRC tissues (36.7% vs 60.8%, p < 0.001). Poor histological differentiation, advanced clinical stage and lymph node metastasis were significantly correlated with the MMP-13 expression in CRC. The overall survival rate of the MMP-13-negative group was significantly higher than the positive group (Log-rank test = 12.452, p < 0.001). Collectively, we found that MMP-13 was correlated with progression and metastasis of CRC and could be used as a prognostic marker in CRC.

Appropriate empirical antifungal therapy is associated with a reduced mortality rate in intensive care unit patients with invasive fungal infection: A real-world retrospective study based on the MIMIC-IV database.

Objective: The study aimed to determine the prevalence and pathogens of invasive fungal infection (IFI) among intensive care unit (ICU) patients. The next goal was to investigate the association between empirical antifungal treatment and mortality in ICU patients. Methods: Using microbiological events, we identified all ICU patients with IFI and then retrieved electronic clinical data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The data were statistically analyzed using t-tests, chi-square tests, log-rank tests, and Cox regression. Results: The most commonly reported fungi were Candida (72.64%) and Aspergillus (19.08%). The most frequently prescribed antifungal medication was fluconazole (37.57%), followed by micafungin (26.47%). In the survival study of ICU patients and patients with sepsis, survivors were more likely to receive empirical antifungal treatment. In contrast, non-empirical antifungal therapy was significantly associated with poor survival in patients with positive blood cultures. We found that the current predictive score makes an accurate prediction of patients with fungal infections challenging. Conclusions: Our study demonstrated that empirical antifungal treatment is associated with decreased mortality in ICU patients. To avoid treatment delays, novel diagnostic techniques should be implemented in the clinic. Until such tests are available, appropriate empirical antifungal therapy could be administered based on a model that predicts the optimal time to initiate antifungal therapy. Additional studies should be conducted to establish more accurate predictive models in the future.

Antisense oligonucleotide targeting matrix metalloproteinase-7 (MMP-7) changes the ultrastructure of human A549 lung adenocarcinoma cells.

Antisense oligonucleotide (ASODN) targeting specific gene can be capable of potently downregulating proliferation and invasion in human cancer cells. However, the underlying mechanisms are less well defined. Here the authors show that matrix metalloproteinase-7 (MMP-7) ASODN changes the ultrastructure of human A549 lung adenocarcinoma cells. Transfection of MMP-7 ASODN significantly lowered the expression of MMP-7 protein in A549 cells. Decreased microvilli, endoplasmic reticulum dilation, swelling of mitochondria, and formation of apoptotic bodies were observed by transmission electron microscope. Collectively, the findings identified the morphological mechanism that MMP-7 ASODN inhibited proliferation and invasion in A549 cells.

Role of the stromal cell derived factor-1 in the biological functions of endothelial progenitor cells and its underlying mechanisms.

Stromal cell derived factor-1 (SDF-1) is a chemokine that plays a critical role in the homing of stem and progenitor cells, including endothelial progenitor cells (EPCs). However, little research has been undertaken to evaluate the roles of SDF-1 in the biological functions of EPCs and related signaling pathways. The present study aimed to investigate the biological functions of EPCs in response to SDF-1, as well as the underlying mechanisms. The effects of SDF-1 treatment on EPC proliferation, migration and tube formation were assessed by performing MTS, Transwell and in vitro tube formation assays, respectively. The phosphorylation status of Akt and ERK was evaluated by western blotting. The present results indicated that SDF-1 treatment enhanced EPC proliferation, migration and tube formation compared with the control group. Furthermore, SDF-1-induced EPC proliferation was significantly reduced following treatment with a C-X-C Motif Chemokine Receptor 4 antagonist (AMD3100), a PI3K inhibitor (LY294002) and the mitogen-activated protein kinase kinase inhibitor (MEK; PD98059). SDF-1-induced migration and angiogenesis were significantly suppressed by the PI3K inhibitor, but not the MEK inhibitor. Moreover, SDF-1 significantly increased the protein expression levels of phosphorylated (p)-Akt and p-ERK; however, SDF-1-induced effects on protein expression were suppressed by AMD3100, LY294002 and PD98059. Thus, SDF-1-induced EPC proliferation was mediated by activation of the Akt and ERK signaling pathways, whereas SDF-1-mediated EPC migration and tube formation only involved activation of the Akt signaling pathway.

Tumor suppressor role of sFRP­4 in hepatocellular carcinoma via the Wnt/ß­catenin signaling pathway.

Hepatocellular carcinoma (HCC) is a malignant tumor located in the liver. Secreted frizzled­related protein 4 (sFRP­4) is associated with cancer occurrence, but the relationship between sFRP­4 and HCC is not completely understood. The present study aimed to investigate the role and mechanism underlying sFRP­4 in HCC. sFRP­4 mRNA expression levels were determined via reverse transcription­quantitative PCR and immunohistochemistry. The Cell Counting Kit­8 assay was performed to evaluate HCCLM3 and Huh7 cell viability. Moreover, HCCLM3 and Huh7 cell proliferation were assessed using the BrdU ELISA assay kit, and cell apoptosis was measured via flow cytometry. Western blotting was conducted to measure ß­catenin and GSK­3ß protein expression levels. The results demonstrated that sFRP­4 expression was significantly downregulated in HCC tissues and cells compared with adjacent healthy tissues and MIHA cells, respectively. Moreover, the results indicated that compared with the control group, sFRP­4 overexpression inhibited HCC cell viability and proliferation, and accelerated HCC cell apoptosis. Furthermore, the results suggested that sFRP­4 inhibited the Wnt/ß­catenin signaling pathway by upregulating GSK­3ß expression and downregulating ß­catenin expression, thus restraining the malignant behavior of HCC cells. In conclusion, the present study indicated that sFRP­4 served a tumor suppressor role in HCC cells by restraining the Wnt/ß­catenin signaling pathway.

Thrombocytopenia in 737 adult intensive care unit patients: A real-world study of associated factors, drugs, platelet transfusion, and clinical outcome.

OBJECTIVE: We aimed to identify and represent factors associated with thrombocytopenia in intensive care unit, especially the pathogens and drugs related to severe and extremely thrombocytopenia. Then, we aim to compare the mortality of platelet transfusion and non-transfusion in patients with different degrees of thrombocytopenia. METHODS: We identified all thrombocytopenic patients in intensive care unit by using platelet-specific values and then extracted electronic health records from our Hospital Information System. Data were statistically analyzed with t test, chi-square test, and logistic regression. RESULTS: We found that infections (32.7%) were the most frequent cause associated with thrombocytopenia, followed by sepsis shock (3.93%) and blood loss (2.99%). Meanwhile, antifungals (p = 0.002) and bacterial infection (p = 0.037) were associated with severe and extremely severe thrombocytopenia. Finally, we found that the mortality of platelet transfusion and non-transfusion in patients was statistically significant for patients with platelet counts between 30 and 49/nL (χ2 = 9.719, p = 0.002). CONCLUSION: Infection and sepsis emerged as two primary factors associated with thrombocytopenia in intensive care unit. Meanwhile, antifungals and bacterial infection were associated with platelet counts less than 49/nL. Finally, platelet transfusion may be associated with reduced mortality in patients with platelet counts between 30 and 49/nL.

A preliminary study on serological assay for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 238 admitted hospital patients.

In this study, we aimed to evaluate the diagnostic value of serological assay for SARS-CoV-2. A newly-developed ELISA assay for IgM and IgG antibodies against N protein of SARS-CoV-2 was used to screen the serums of 238 admitted hospital patients between February 6 and February 14, 2020 with confirmed or suspected SARS-CoV-2. SARS-CoV-2 RNA was detected on pharyngeal swab specimens using real time RT-PCR. 194 (81.5%) of the serums were detected to be antibody (IgM and/or IgG) positive, significantly higher than the positive rate of viral RNA (64.3%). There was no difference in the positive rate of antibodies between the confirmed patients (83.0%, 127/153) and the suspected patients (78.8%, 67/85), whose nucleic acid tests were negative. The antibody positive rates were very low in the first five days after initial onset of symptoms, and then rapidly increased as the disease progressed. After 10 days, the antibody positive rates jumped from below 50% to over 80%. However, the positive rates of viral RNA maintained above 60% in the first 11 days after initial onset of symptoms, and then rapidly decreased. Overall, the suspected patients were most likely infected by SARS-CoV-2. Before the 11th day after initial onset of symptoms, nucleic acid test is key for confirmation of viral infection. The combination of serological assay can greatly improve the diagnostic efficacy. After the 11th day post-disease onset, the diagnosis for viral infection should be majorly dependent on serological assay.

Alternatively activated RAW264.7 macrophages enhance tumor lymphangiogenesis in mouse lung adenocarcinoma.

Tumor-associated macrophages (TAMs) have been implicated in promoting tumor progression and invasion. The onset and maintenance of tumor angiogenesis and lymphangiogenesis also seem to be partly driven by a group of polarized alternatively activated macrophages (aaMphi) in lung adenocarcinoma. Here, the aaMphi and classically activated macrophages (caMphi) were obtained using RAW264.7 cells via IL-4 and IFN-gamma + LPS treatment, respectively. Co-inoculation of aaMphi with Lewis lung carcinoma (LLC) cells promoted tumor growth, increased lymph node metastasis, and reduced the survival in C57BL/6 mice bearing LLC. Furthermore, the effects of the activated macrophages on the lymphangiogenesis-related properties of lymphatic endothelial cells (LECs) were investigated in vitro. When LECs were cultured in macrophages conditioned medium or in a co-culture system of macrophages and LECs, aaMphi significantly promoted proliferation, migration, and tube-like formation of LECs. We identified high VEGF-C expression in aaMphi and low expression in caMphi as well as unactivated macrophages by ELISA and Western blotting. In LECs, co-culture with aaMphi resulted in a significant increase of mRNA levels of specific lymphatic marker VEGF receptor-3 and the homeobox gene Prox-1, as well as lymphangiogenic factor VEGF-C rather than VEGF-D by quantitative RT-PCR. Furthermore, enhanced LECs migration and capillary formation by co-culture with aaMphi were significantly inhibited by rVEGF receptor-3/Fc chimera. In conclusion, these data show that aaMphi play a critical role in tumor-induced lymphangiogenesis through up-regulating VEGF-C and increasing lymphangiogenesis-related behavior of LECs, which may contribute to lymphatic invasion in lung adenocarcinoma.

Variation of δ18O in precipitation and its response to upstream atmospheric convection and rainout: A case study of Changsha station, south-central China.

The results of analyses of the stable isotopes of oxygen in precipitation (δ18Op) are presented for every rainfall event from January 2010 to December 2017 in Changsha, south-central China. Our aims were to elucidate the variations of δ18Op on different timescales and to identify the main meteorological drivers of variations in the oxygen isotopic composition of precipitation. Results showed that there were no statistically significant and consistent negative correlations between δ18Op and local precipitation amount on either daily or monthly timescale; however, changes in δ18Op in Changsha responded sensitively to the variation of precipitation in the key upstream area along air mass trajectories. Year-to-year, the strongest negative lagged correlations (r') between δ18Op and the preceding average precipitation amount varied from -0.79 to -0.63 (all significant at the 0.001 level) in the warm half-year (from April to September) of 2010-2017. However, in the cold half-year (from October to the following March), corresponding r' values varied from -0.79 to -0.38 that were all significant at the 0.001 level, except for the year 2012. These findings suggest that the amplitude of the isotopic signal was closely linked with the position and intensity of upstream rainout activity. This was supported by strong relationships between precipitation-weighted mean δ18O (δ18Ow) and average precipitation amount in the key upstream area at the monthly scale; correlation coefficients were - 0.76 and - 0.57 between 2010 and 2017 in the warm half-year and cold half-year, respectively (both significant at the 0.001 level). Results advance our understanding of the temporal variation of the stable oxygen isotopic composition of precipitation, and demonstrate that local isotopic proxy records may be influenced by upstream rainout processes.