A novel polysaccharide obtained from Craterellus cornucopioides enhances immunomodulatory activity in immunosuppressive mice models via regulation of the TLR4-NF-κB pathway

The immunoregulatory effect of a novel Craterellus cornucopioides polysaccharide (CCP) with a triple-helix structure on immunosuppressive BALB/c mice models was investigated; moreover, the immune response of BALB/c mice models in the preventive and therapeutic treatment groups treated with CCP was explored, and its molecular mechanism was elucidated. It was found that the BALB/c mice models in the preventive groups treated with CCP (120 and 240 mg kg^-1 d^-1) had better immunoregulatory activity. The spleen and thymus weight indices of the BALB/c mice models were significantly increased, and the histopathological analysis indicated a protective function of CCP against the immunosuppression induced by cyclophosphamide (CTX). Moreover, CCP displayed definite and clear synergistic effects on the T- or B-lymphocyte proliferation induced by ConA or LPS, respectively, promoted the natural killer (NK) cell activity and significantly increased phagocytic activity to activate peritoneal macrophages in immunosuppressive mice. The western blot and quantitative real-time polymerase chain reaction (qRT-PCR) results provided comprehensive evidence that CCP could upregulate the protein expression of the G-protein-coupled cell membrane receptor TLR4 and the production of its downstream protein kinases (TRAF6, TK1, p-IKKα/β and NF-κB p50); this, in turn, enhanced the production of cytokines (IL-2, IL-6, TNF-α and IFN-α) through both preventive and therapeutic treatments via regulation of the TLR4-NFκB pathway in the peritoneal macrophage of immunosuppressive mice.

Selective activation of tumor-suppressive MAPKP signaling pathway by triptonide effectively inhibits pancreatic cancer cell tumorigenicity and tumor growth

The mitogen-activated protein kinase (MAPK, 1K) family members ERK, JNK, and p38 play a divergent role in either promoting tumorigenesis or tumor-suppression. Activation of ERK and JNK promotes tumorigenesis; whereas, escalation of p38 inhibits carcinogenesis. As these three MAPK members are controlled by the common up-stream MAPK signaling proteins which consist of MAPK kinases (2K) and MAPK kinase kinases (3K), how to selectively actuate tumor-suppressive p38, not concurrently stimulate tumorigenic ERK and JNK, in cancer cells is a challenge for cancer researchers, and a new opportunity for novel anti-cancer drug discovery. Using human pancreatic cancer cells and xenograft mice as models, we found that a small molecule triptonide first discerningly activated the up-stream MAPK kinase kinase MEKK4, not the other two 3K members ASK1 and GADD45; and then selectively actuated the middle stream MAPK kinase MKK4, not the other two 2K members MKK3 and MKK6; and followed by activation of the MAPK member p38, not the other two members ERK and JNK. These data suggest that triptonide is a selective MEKK4-MKK4-p38 axis agonist. Consequently, selective activation of the MEKK4-MKK4-p38 signaling axis by triptonide activated tumor suppressor p21 and inhibited CDK3 expression, resulting in cancer cell cycle arrest at G2/M phase and marked inhibition of pancreatic cancer cell tumorigenic capability in vitro and tumor growth in xenograft mice. Our findings support the notion that selective activation of tumor-suppressive MEKK4-MKK4-p38-p21signaling pathway by triptonide is a new approach for pancreatic cancer therapy, providing a new drug candidate for development of novel anti-cancer therapeutics.

An Integrated Model for Input and Migration of Mercury in Chinese Coastal Sediments

Coastal sediments are a major sink of the global mercury (Hg) biogeochemical cycle, bridging terrestrial Hg migration to the open ocean. It is thus of substantial interest to quantify the Hg contributors to coastal sediments and the extents to which the Hg sequestered into coastal sediments affects the ocean. Here, we measured concentrations and isotope compositions of Hg in Chinese coastal sediments and found that estuary sediments had distinctly higher δ²⁰²Hg and lower Δ¹⁹⁹Hg values than marine sediments. Hg isotope compositions of marine sediments followed a latitudinal trend where δ²⁰²Hg decreases and Δ¹⁹⁹Hg increases from north to south. An integrated model was developed based on a Hg isotope mixing model and urban distance factor (UDF), which revealed a significant difference in Hg source contributions among the estuary and marine sediments and a gradual change of dominant Hg sources from terrestrial inputs (riverine and industrial wastewater discharges) to atmospheric deposition with a decrease in urban impact. A UDF value of 306 ± 217 was established as the critical point where dominant Hg sources started to change from terrestrial inputs to atmospheric deposition. Our study helps explain the input and migration of Hg in Chinese marginal seas and provides critical insights for targeted environmental management.

Protective Effects of Live Combined B. subtilis and E. faecium in Polymicrobial Sepsis Through Modulating Activation and Transformation of Macrophages and Mast Cells

Aims: Clinical studies showed that the use of probiotics during critical illness reduced nosocomial infection and improved clinical outcome. However, the functional mechanisms of probiotics is remains unclear. Therefore the aim of current study is to explore the protective effects and understand the underlying mechanisms for the beneficial effects of live combined Bacillus subtilis and Enterococcus faecium (LCBE) in cecal ligation puncture (CLP)-induced sepsis.

Methods and Results: Seven-week-old C57BL/6J mice were divided into three groups: sham group (6 mice), CLP-control group (20 mice, pretreatment with saline for 7 days before CLP surgery) and CLP-probiotics group (14 mice, pretreatment with LCBE enteric-coated capsules for 7 days before CLP surgery). In survival experiment, mice were monitored for 7 days after CLP. After the procedure, mice were sacrificed, and, serum, and peritoneal lavage fluid were collected and intestinal ileal samples were harvested.

Results: Our results showed that the mortality was significantly reduced in mice CLP-probiotics group vs. CLP-control group (P < 0.05). Also, treatment CLP-probiotics group decreased the injury scores CLP-probiotics group when compared to CLP-control group. Additionally, levels of pro-inflammatory cytokines IL-6 and TNF-α levels in the serum and intestinal ileal tissues of CLP-probiotics group were reduced when compared to CLP-control group (P < 0.05). However, no significant differences in anti-inflammatory levels of IL-10 and TGF-β1 were observed between CLP-control and CLP-probiotic groups. Furthermore, our experiments showed that that probiotic treatment suppressed the macrophage activation and transformation from M-type to M1-type, inhibited the mast cells (MCs) degranulation, and activation of AKT (kinase B) pathway.

Conclusion: In conclusion, our data shows that probiotics have a protective role in CLP septic mice through reducing intestinal inflammation, altering macrophage polarization and MCs degranulation, and regulating AKT signaling.

Significance and Impact of Study: This study demonstrated the protective effects and mechanisms involved in the protective role of live combined Bacillus subtilis and Enterococcus faecium (LCBE) in CLP-induced septic mice model.

Structure characterization, physicochemical property and immunomodulatory activity on RAW264.7 cells of a novel triple-helix polysaccharide from Craterellus cornucopioides

In the study, a new triple-helix polysaccharide with favorable stability was purified from C. cornucopioides. Its structural characterization, stability and solution behavior were investigated by the GC-MS, periodate oxidation-smith degradation, FT-IR, 1D and 2D NMR spectroscopy, methylation analysis, Scanning electron microscope, Congo-red, CD, TGA and DSC analysis. The results showed that Craterellus cornucopioide polysaccharide (CCP) possessed the molecular weight of 1.97 × 10³ kDa, is mainly composed of mannose (48.73%), galactose (17.37%), glucose (15.97%) and xylose (17.93%), respectively. It was a heteroglycan with (1 → 3)‑linked‑β‑d‑Manp‑(1 → 6)‑linked α‑d‑Galp backbone distributed by (1 → 4)‑linked‑α‑d‑Xylp‑t‑α‑d‑Manp and t‑β‑d‑Glup units at O-6. The result of TGA and DSC assay indicated that CCP has a favorable thermal stability. MTT and Scanning electro microscopy (SEM) assay showed that CCP could significantly improve the proliferation activity and induce cells activation of RAW264.7 in a certain range of concentrations and period.

Pharmacological preconditioning with the cellular stress inducer thapsigargin protects against experimental sepsis

Previous studies have shown that pretreatment with thapsigargin (TG), a cellular stress inducer, produced potent protective actions against various pathologic injuries. So far there is no information on the effects of TG on the development of bacterial sepsis. Using lipopolysaccharides- and cecal ligation/puncture-induced sepsis models in mice, we demonstrated that preconditioning with a single bolus administration of TG conferred significant improvements in survival. The beneficial effects of TG were not mediated by ER stress induction or changes in Toll-like receptor 4 signaling. In vivo and in cultured macrophages, we identified that TG reduced the protein production of pro-inflammatory cytokines, but exhibited no significant effects on steady state levels of their transcriptions. Direct measurement on the fraction of polysome-bound mRNAs revealed that TG reduced the translational efficiency of pro-inflammatory cytokines in macrophages. Moreover, we provided evidence suggesting that repression of the mTOR (the mammalian target of rapamycin) signaling pathway, but not activation of the PERK (protein kinase R-like endoplasmic reticulum kinase)-eIF2α (eukaryotic initiation factor 2α) pathway, might be involved in mediating the TG effects on cytokine production. In summary, our results support that pharmacological preconditioning with TG may represent a novel strategy to prevent sepsis-induced mortality and organ injuries.

Identification of the lncRNA, AK156230, as a novel regulator of cellular senescence in mouse embryonic fibroblasts

Long noncoding RNAs (lncRNAs) have gained extensive attentions in recent years because of their potential importance in a variety of biological and pathological processes. In this study, we sought to explore the role of lncRNAs in cellular senescence. Here, we report that the lncRNA AK156230 was downregulated during replicative senescence in mouse embryonic fibroblasts (MEFs), and knockdown of AK156230 promotes a robust senescence phenotype, including increase in the numbers of the senescence-associated β-galactosidase-positive cells, decrease of cell proliferation, accumulation of cells in the G2/M phase and reduction of autophagic activity. The cells with knockdown AK156230 expression also exhibited increased levels of p21, p53 and phosphorylated p53, and a decreased activity of CDK1. Moreover, rapamycin-induced autophagy offered cytoprotective effect and rescued cellular senescence in AK156230 knockdown cells. Gene expression profile showed that the dysregulation of autophagy and cell cycle genes contributed to the induction of cellular senescence after AK1561230 silencing. Taken together, these results suggest that downregulation of AK156230 is involved in the induction of cellular senescence through its roles in autophagy and cell cycle progression. Our study identifies AK156230 as a critical lncRNA that has a role in regulating cellular senescence in MEFs.

Gas chromatography-time of flight/mass spectrometry-based metabonomics of changes in the urinary metabolic profile in osteoarthritic rats

The aim of the present study was to explore changes in the urinary metabolic spectrum in rats with knee osteoarthritis, using gas chromatography-time of flight/mass spectrometry (GC-TOF/MS) to determine the metabonomic disease pathogenesis. Sprague-Dawley rats were randomly divided into the control and model groups (n=8/group), and 20 µl of 4% papain and 0.03 M L-cysteine was injected into the right knee on days 1, 3 and 7 to establish the knee osteoarthritis model. Following 14 days, urine was collected over 12 h and cartilage ultrastructural damage was assessed by hematoxylin-eosin staining. GC-TOF/MS, combined with principal component analysis, partial least squares discriminant modeling and orthogonal partial least squares discriminant modeling, was used to analyze the changes in the metabolic spectrum trajectory and to identify potential biomarkers and their related metabolic pathways. Compared with the control group, the synovial cell lining of the knee joint exhibited proliferation, inflammatory cell infiltration and collagen fiber hyperplasia in the knee osteoarthritis group. A total of 23 potential biomarkers were identified, including alanine, α-ketoglutarate, asparagine, maltose and glutamine. Furthermore, metabolomic pathogenesis of osteoarthritis may be related to disorders of amino acid metabolism, energy metabolism, fatty acid metabolism, vitamin B₆ metabolism and nucleic acid metabolism.

[Investigation of sagittal root position in relation to the anterior maxillary alveolar bone: a cone-beam CT study in 300 cases with normal occlusion]

Objective: To investigate the sagittal root position and apical bone height of the maxillary anterior teeth in order to provide anatomical information for immediate implant placement in the esthetic region. Methods: Cone-beam CT (CBCT) data from 300 randomly selected patients who met the inclusion criteria were included in this study. After three-dimensional reconstruction, the sagittal plane (the sagittal plane through the long axis of the tooth) was determined. The positions and angulations of the tooth roots were classified with reference to the alveolar process. By comparing the buccal and palatal bone thickness at the mid-root level, the toot positions with reference to the mid-alveolar line were defined and classified as follows, type B (closer to the buccal alveolar surface), type M (midway between the buccal and palatal alveolar surface) and type P (closer to the palatal alveolar surface). By comparing the angulations of the alveolar process with the long axis of the roots, the angulations were classified as follows, type 1 (root apex angulated toward the palatal side or parallel to the alveolus), type 2 (root apex angulated toward the buccal side with the long axis passing posterior to point A) and type 3 (root apex angulated toward the buccal side with the long axis passing anterior to point A). The frequency of each category was counted and the apical bone height was measured. The subjects were divided into three age groups, 19-30 years, 31-50 years and 51-75 years. Results: The overall mean apical bone height of the healthy maxillary central incisors was (9.2±3.0) mm, the lateral incisors was (10.0±2.9) mm and the canine was (8.1±3.1) mm. There was no significant difference in the height of apical bone between central incisors and lateral incisors (P>0.05). There was no significant difference in the height of apical bone between male and female (P>0.05). The height of apical bone in group 31-50 years and 51-75 years were greater than that in group 19-30 years (P<0.05), respectively. The proportion of the maxillary anterior teeth type B, M, P was 98.5% (1 774/1 800), 0.3% (5/1 800) and 1.2% (21/1 800) respectively. The proportion of type 1, 2, 3 was 2.6% (46/1 800), 58.6% (1 055/1 800) and 38.8% (699/1 800) respectively. Conclusions: There was enough apical bone height in the area of maxillary anterior teeth, but the majority of roots positioned more buccally.

[Optimum population analysis of Jilin Province, China based on comprehensive carrying capacity.]

The regional moderate population model was constructed using state-space method, and the weights of relevant factors were obtained using principal component analysis. The optimum population of Jilin Province during 2005-2014 was calculated and the causes for its formation were discussed. The results showed that the optimum population of Jilin Province was in deficit from 2005-2014, and the imbalance existed between the population, resources and environment. The resources carrying population was significantly higher than the economic carrying and the ecological carrying population, indicating that the economic development of Jilin Province was established at the expense of destroying the environment. Moreover, the land resources carrying population was substantially higher than the water and energy carrying population, which was at a deficit, indicating that the economic development of Jilin Province was based on the depletion of energy and water resources. In the future, water resources carrying capacity should be improved according to the local conditions, the energy efficiency should be enhanced via the development of new energy sources, the extensive and consumption-based resource utilization should be transformed to the intensive and low-carbon type, and the production mode and consumption patterns should be changed to protect the ecological environment.

Red blood cell distribution width as a risk factor for inhospital mortality in obstetric patients admitted to an intensive care unit: a single centre retrospective cohort study

BACKGROUND

Red blood cell distribution width (RDW) has been shown to predict mortality in critically ill patients. To our knowledge, whether or not RDW is associated with clinical outcomes of obstetric patients requiring critical care has not been evaluated.

METHODS

This was a single centre, retrospective, observational study of obstetric patients admitted to the intensive care unit (ICU). Patients were excluded from the analysis if they had known haematological diseases or recently underwent blood transfusion. Patients who died or were discharged from the ICU within 24 hours of admission were also excluded. Patient clinical characteristics at ICU admission were retrieved from the medical charts. Multiple logistic regression was used to estimate OR and 95% CI for inhospital mortality associated with RDW. The receiver operating characteristic curve was used to examine the performance of RDW, alone or in combination with the Acute Physiology and Chronic Health Evaluation II score (APACHE II), in predicting inhospital mortality.

RESULTS

A total of 376 patients were included in the study. The hospital mortality rate was 5.32%. A significant association was found between baseline RDW levels and hospital mortality (OR per per cent increase in RDW, 1.31; 95% CI 1.15 to 1.49). Further adjustment for haematocrit and other potential confounders did not appreciably alter the result (p<0.001). The area under the curve (AUC) for inhospital mortality based on RDW was similar to that based on the APACHE II score (0.752 vs 0.766). A combination of these two factors resulted in substantial improvement in risk prediction, with an AUC value of 0.872 (p<0.001).

CONCLUSIONS

The study suggests that RDW is an independent predictor for inhospital mortality among ICU admitted obstetric patients. Combining RDW and APACHE II score could significantly improve inhospital prognostic prediction among these critically ill obstetric patients.

Myosin light chain kinase knockout improves gut barrier function and confers a survival advantage in polymicrobial sepsis

Sepsis-induced intestinal hyperpermeability is mediated by disruption of the epithelial tight junction, which is closely associated with the peri-junctional actin-myosin ring. Myosin light chain kinase (MLCK) phosphorylates the myosin regulatory light chain, resulting in increased permeability. The purpose of this study was to determine whether genetic deletion of MLCK would alter gut barrier function and survival from sepsis. MLCK^-/- and wild type (WT) mice were subjected to cecal ligation and puncture and assayed for both survival and mechanistic studies. Survival was significantly increased in MLCK^-/- mice (95% vs. 24%, p<0.0001). Intestinal permeability increased in septic WT mice compared to unmanipulated mice. In contrast, permeability in septic MLCK^-/- mice was similar to that seen in unmanipulated animals. Improved gut barrier function in MLCK^-/- mice was associated with increases in the tight junction mediators ZO-1 and claudin 15 without alterations in claudin 1, 2, 3, 4, 5, 7, 8, 13, occludin or JAM-A. Other components of intestinal integrity (apoptosis, proliferation and villus length) were unaffected by MLCK deletion as were local peritoneal inflammation and distant lung injury. Systemic IL-10 was decreased greater than 10-fold in MLCK^-/- mice; however, survival was similar between septic MLCK^-/- mice given exogenous IL-10 or vehicle. These data demonstrate that deletion of MLCK improves survival following sepsis, associated with normalization of intestinal permeability and selected tight junction proteins.

Chlorinated Polyfluoroalkyl Ether Sulfonic Acids in Marine Organisms from Bohai Sea, China: Occurrence, Temporal Variations, and Trophic Transfer Behavior

F-53B, the commercial product of chlorinated polyfluoroalkyl ether sulfonic acids (Cl-PFESAs), has been used in Chinese chrome plating industry for 30 years, and was recently identified in the environment, which caused great concerns. So far, limited investigations have been performed on their environmental occurrence, fate and impact. In this study, we demonstrated the wide occurrence of Cl-PFESAs and their trophic transfer behavior in marine organisms from Chinese Bohai Sea. 6:2 Cl-PFESA (<0.016-0.575 ng/g wet weight) was the dominant congener, and 8:2 Cl-PFESA (<0.022-0.040 ng/g) was occasionally detected. Compared to other perfluoroalkyl and polyfluoroalkyl substances (PFASs) of concern, the levels of Cl-PFESAs were relatively lower in marine organisms. Based on the comparative analysis of Cl-PFESA contamination in mollusk samples collected in 2010-2014, both the concentrations and detection frequencies of Cl-PFESAs tended to increase in this region. And this kind of chemicals were more vulnerable to be accumulated in marine organisms at relatively higher trophic levels. Similar to perfluorooctanesulfonate (PFOS) and the long chain perfluorinated carboxylates (PFCAs), 6:2 Cl-PFESA could be magnified along the food chain. Accordingly, the potential threat might be posed to the wildlife and human beings due to unintended exposure to Cl-PFESAs.

New insights into the gut as the driver of critical illness and organ failure

PURPOSE OF REVIEW

The gut has long been hypothesized to be the 'motor' of multiple organ dysfunction syndrome. This review serves as an update on new data elucidating the role of the gut as the propagator of organ failure in critical illness.

RECENT FINDINGS

Under basal conditions, the gut absorbs nutrients and serves as a barrier that prevents approximately 40 trillion intraluminal microbes and their products from causing host injury. However, in critical illness, gut integrity is disrupted with hyperpermeability and increased epithelial apoptosis, allowing contamination of extraluminal sites that are ordinarily sterile. These alterations in gut integrity are further exacerbated in the setting of preexisting comorbidities. The normally commensal microflora is also altered in critical illness, with increases in microbial virulence and decreases in diversity, which leads to further pathologic responses within the host.

SUMMARY

All components of the gut are adversely impacted by critical illness. Gut injury can not only propagate local damage, but can also cause distant injury and organ failure. Understanding how the multifaceted components of the gut interact and how these are perturbed in critical illness may play an important role in turning off the 'motor' of multiple organ dysfunction syndrome in the future.

Cigarette smoke extracts induce overexpression of the proto-oncogenic gene interleukin-13 receptor α2 through activation of the PKA-CREB signaling pathway to trigger malignant transformation of lung vascular endothelial cells and angiogenesis

Cigarette smoking is a major cause of lung cancer. Tumor-associated endothelial cells (TAECs) play important roles in tumor angiogenesis and metastasis. However, whether cigarette smoking can trigger genesis of lung TAECs has not been reported yet. In the current study, we used lung endothelial cell (EC) lines as a model to study the pathological effect of cigarette smoke extracts (CSEs) on human lung ECs, and found that a lower dose of 4% CSEs obviously caused abnormal morphological changes in ECs, increased the permeability of endothelial monolayer, while a higher concentration of 8% CSEs caused EC apoptosis. Strikingly, CSEs induced a 117-fold overexpression of a pro-tumorigenic interleukin-13 receptor α2 gene (IL-13Rα2, also named as CT-19) through activation of the protein kinase A (PKA) and cAMP response element-binding protein (CREB) signaling pathway. A PKA specific inhibitor H89 completely abolished CSEs-induced IL-13Rα2 overexpression. The overexpression of IL-13Rα2 in lung ECs significantly increased the tumorigenic, migratory, and angiogenic capabilities of the cells, suggesting that IL-13Rα2 promotes genesis of lung TAECs. Together, our data show that CSEs activate the PKA, CREB, and IL-13Rα2 axis in lung ECs, and IL-13Rα2 promotes the malignant transformation of lung ECs and genesis of TAECs with robust angiogenic and oncogenic capabilities. Our study provides new insight into the mechanism of CSEs-triggered lung cancer angiogenesis and tumorigenesis, suggesting that the PKA-CREB-IL-13Rα2 axis is a potential target for novel anti-lung tumor angiogenesis and anti-lung cancer drug discovery.

Bronchopleural fistula after lung ablation: Experience in two cases and literature review

BACKGROUND

Bronchopleural fistula (BPF) complicating lung tumor ablation is rare but severe. The purpose of this article was to study its characteristics and treatments.

MATERIALS AND METHODS

Two of 682 (0.3%) sessions of lung microwave ablation (MWA) were complicated with BPF and documented. Two electronic databases were searched for reported cases of BPF after lung tumor ablation. Case selection and data collection were done by 3 independent reviewers.

RESULTS

A 56-year-old man and a 61-year-old woman developed BPF after MWA and died. Thirteen cases (mean age 63.8, 61.5% male) of BPF with adequate information were identified from 8 articles. Of the 13 cases, 5 (38.5%) had pulmonary co-morbidity, 3 (23.1%) had a history of pulmonary surgery, 7 (53.8%) had a target tumor adjacent or abutting pulmonary pleura, and 6 (46.2%) developed severe infections. After chest tube placement, pleurodesis, endoscopic therapy, surgery, and other treatments, 12 were cured and 1 died of BPF and pneumonia.

CONCLUSION

BPF is a rare but severe complication of lung ablation, and the management needs a multidisciplinary and individualized treatment strategy.