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Yi-Lin Zhang,1 Yan-Ping Wang,1 Tao Sun,2 Yi-Nan Tian,1 Xia-Xia Qin,1 Xin-Yu Duan,1 Yu-Tian Gan,1 Guan-Jun Wang,1 Li-Bin Yang,1,* Shu-E Zhang1,* 1Department of Health Management, School of Health Management, Harbin Medical University, Harbin, Heilongjiang, People’s Republic of China; 2Department of Health Policy and Management, School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, People’s Republic of China*These authors contributed equally to this workCorrespondence: Li-Bin Yang; Shu-E Zhang, Department of Health Management, School of Health Management, Harbin Medical University, Harbin, 150081, People’s Republic of China, Email yanglib@126.com; hydzhangshue@163.comPurpose: Transformational leadership among core hospital leaders boosts medical organizations’ competitiveness, adaptability, and sustainability, which is jointly affected by individual, organizational and environmental factors. This study aims to unpack its configurational framework and propose strategies to strengthen core hospital leaders’ transformational leadership.Patients and Methods: Data were collected from an online questionnaire among 31 core hospital leaders. The fuzzy-set qualitative comparative analysis (fsQCA) was used to explore the causal mechanism of high-level transformational leadership. We enrich this mechanism by professional background, critical thinking, initiative spirit, family-work conflict, job satisfaction, subordinates’ followership, and work pressure.Results: Result shows initiative spirit is the only necessary condition (consistency=0.911) for the formation of high-level transformational leadership among core hospital leaders. Three configurations are the sufficient conditions that lead to high-level transformational leadership among core hospital leaders with two different professional backgrounds (overall solution consistency= 0.952).Conclusion: Core hospital leaders’ initiative spirit is an indispensable condition for improving high-level transformational leadership, emphasizing the necessity for core leaders to be proactive in order to develop such leadership. Besides, the study also uncovered three configurations are the sufficient conditions for core hospital leaders with diverse professional backgrounds to achieve high-level transformational leadership. This finding offers significant insights into hospital management practices, suggesting that core hospital leaders’ work should be managed in a personalized manner based on their professional backgrounds, thereby fostering favorable conditions conducive to the development of their high-level transformational leadership capabilities. Furthermore, the central insight of this study is that the formation of high-level transformational leadership contingent upon the collaboration of professional background, critical thinking, initiative spirit, family-work conflict, job satisfaction, subordinates’ followership, and work pressure, contributing to a holistic and more rigorous view for the development of transformational leadership.Keywords: transformational leadership, core hospital leaders, hospital management, configuration, fsQCA

Objective: Atherosclerotic cardiovascular disease poses a significant health challenge globally. Recent findings highlight the pivotal role of the endothelial-to-mesenchymal transition (EndMT) in atherosclerosis. Morin is a bioflavonoid mainly extracted from white mulberry, a traditional Chinese herbal medicine with anti-inflammatory and antioxidant properties. This study examines whether morin can alleviate atherosclerosis by suppressing EndMT and seeks to elucidate the underlying mechanism., Methods: We induced an in vitro EndMT model in human umbilical vein endothelial cells (HUVECs) by stimulating the cells with transforming growth factor-β1 (TGF-β1) (10 ng/mL) for 48 h. The in vivo experiments were performed in an atherosclerosis model using apolipoprotein E (ApoE) -/- mice fed with a high-fat diet (HFD). Mice in the intervention group were given morin (50 mg/kg) orally for 4 weeks. Molecular docking and microscale thermophoresis were assayed to understand the interactions between morin and matrix metalloproteinase-9 (MMP-9)., Results: Morin inhibited the expression of EndMT markers in a dose-dependent manner in TGF-β1-treated HUVECs. Administering 50 μmol/L morin suppressed the upregulation of MMP-9 and Notch-1 signaling in TGF-β1-induced EndMT. Moreover, the overexpression of MMP-9 activated Notch-1 signaling, thereby reversing morin's inhibitory effect on EndMT. In the HFD-induced atherosclerotic ApoE -/- mice, morin notably reduced aortic intimal hyperplasia and plaque formation by suppressing EndMT. Furthermore, morin demonstrated a strong binding affinity for MMP-9., Conclusion: Morin acts as an MMP-9 inhibitor to disrupt EndMT in atherosclerosis by limiting the activation of Notch-1 signaling. This study underscores morin's potential utility in the development of anti-atherosclerotic medication. Please cite this article as: He Y, Qin XX, Liu MW, Sun W. Morin, a matrix metalloproteinase 9 inhibitor, attenuates endothelial-to-mesenchymal transition in atherosclerosis by downregulating Notch-1 Signaling. J Integr Med. 2024; Epub ahead of print., (Copyright © 2024 Shanghai Yueyang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine. Published by Elsevier B.V. All rights reserved.)

Purpose: To assess satisfaction and preference among rugby union players for custom mouthguards with and without labial reinforcement, and to assess discomfort and perceived protection., Materials and Methods: This prospective RCT used a crossover design of four 1-week periods to compare conventional (Type A) and labial reinforced (Type B) customized mouthguards for rugby union players from February to May 2022. Type B mouthguards included a 0.75-mm insert of polyethylene terephthalate glycol (Duran) in the anterior labial region. We ensured intraoral occlusion accommodation for both mouthguards. Players wore each mouthguard type when training and in competitive matches for 2 weeks according to one of two randomized sequences. After each session, they rated the mouthguard on 10-point scales regarding discomfort, functional interference, protection, and general satisfaction. After 4 weeks, we asked participants to nominate their preferred mouthguard., Results: In total, 22 of the 24 invited players (16 men and 6 women) were included. We observed no significant differences in discomfort, functional interference, protection, or general satisfaction by mouthguard type (P > .05, Wilcoxon test). Ultimately, 12 players (55%) preferred the Type A mouthguard and 10 (45%) preferred the Type B mouthguard (P = .832; one-sample binomial test). No serious adverse events occurred., Conclusions: Labial reinforcement does not affect satisfaction, perceived comfort and protection, or mouthguard preference among rugby union players.

Objective: The World Health Organization (WHO) defines infertility as a person failing to achieve a pregnancy after 12 months or more of regular unprotected sexual intercourse. Infertility includes female infertility and male infertility. The aim of this paper is to study the etiology of infertility and related influencing factors in men of reproductive age in Jinan., Patients and Methods: In this study, 172 male infertile patients who attended the Department of Assisted Reproduction of Shandong Provincial Maternal and Child Health Hospital in Shandong, China and the Infertility Clinic of Jinan Central Hospital in Shandong, China from August 2021 to April 2022 are selected as the study population (infertility group). A convenience sampling method is used to select 257 men from couples attending the Obstetrics Department of Qilu Hospital in Shandong, China, the Obstetrics Department of the Second Hospital of Shandong University in Shandong, China, and the Obstetrics Department of Maternal and Child Health Hospital in Shandong, China from October 2021 to February 2022 as the study subjects (control group). A self-designed questionnaire is used to conduct the survey, which includes basic personal information, lifestyle information, marital and family-related information, and one-way and multi-way logistic regression analyses are performed., Results: The average age of the case group and the control group are 34.03±5.13 years old and 33.61±8.18 years old; the average height is 175.80±5.91 cm and 176.78±5.25 cm; the average weight is 80.28±14.70 kg and 83.09±45.36 kg. The differences in age, height, and weight between the case group and the control group are not statistically significant by t-test. Moderate oligospermia is the predominant cause of infertility in men of reproductive age in Jinan. A multifactorial logistic regression analysis yields that academic qualifications (OR=2.518, 95% CI: 1.023 to 6.196), coffee consumption (OR=7.692, 95% CI: 1.623 to 36.460), living in a room that had been renovated within a period of time (OR=2.769, 95% CI: 1.104 to 6.949), stress level (OR=47.280, 95% CI: 23.656-94.494), quality of sexual life (OR=3.352, 95% CI: 1.331-8.442), and duration of couple separation (OR=3.851, 95% CI: 1.094-13.557) are the main risk factors for infertility in men of reproductive age in Jinan., Conclusions: In this study, a total of 6 risk factors are screened for male infertility in Jinan in the reproductive age, including high academic qualifications, coffee consumption, living in a room that has finished renovation within 3 months, high stress, poor quality of sexual life, and long spousal separation. Three factors can be controlled, avoided, or reduced through personal actions; the factors are coffee consumption, living in a room that has finished renovation within 3 months, and high stress, all of which may reduce the level of male reproductive health.

Objective: To provide evidence for optimizing the screening strategy for gastric cancer (GC), we evaluated the risk of incident GC for individuals with different precancerous gastric lesions in a prospective cohort study. Methods: Based on the National Upper Gastrointestinal Cancer Early Detection Program launched in Linqu, Shandong, a high-risk area of gastric cancer in China, we included a total of 14 087 subjects diagnosed with different gastric lesions stages by endoscopic screening from 2012 to 2018. Study subjects were prospectively followed up until December 31, 2019. The incidence of GC during the follow-up was ascertained by repeated endoscopic examinations, cancer, death registry reports, and active follow-up of study subjects and was confirmed by reviewing medical records extracted from the hospital information management system. The Poisson regression model was applied to calculate the relative risk ( RR ) and 95% CI for GC occurrence among subjects with different gastric lesions. Results: Among 14 087 subjects with different gastric lesions as determined by their first endoscopic examination in 2012-2018, 7 608 (54.00%) had a global diagnosis of superficial gastritis (SG), 2 848 (20.22%) had chronic atrophic gastritis (CAG), 3 103 (22.03%) had intestinal metaplasia (IM), and 520 (3.69%) had low-grade intestinal neoplasia (LGIN). During the follow-up, 109 subjects were diagnosed with GC, including 63 with high-grade intestinal neoplasia (HGIN) and 46 with invasive GC. Compared to subjects having normal gastric mucosa or SG, those with CAG ( RR =3.85, 95% CI : 2.04-7.28), IM ( RR =5.18, 95% CI : 2.79-9.60), and LGIN ( RR =19.08, 95% CI : 9.97-36.53) had significantly increased risk of progression to GC. Individuals with these gastric lesions had an elevated risk of developing HGIN and invasive GC. For subjects with LGIN, the RR was 22.96 (95% CI : 9.71-54.27) for developing HGIN and 14.64 (95% CI : 5.37-39.93) for developing invasive GC. Subgroup analyses found that all age group subjects with LGIN diagnosed during the initial endoscopic examination had a significantly increased risk of developing the GC. Conclusions: Our large-scale prospective study on a high-risk area of GC showed that most residents aged 40-69 years had gastric lesions of different stages. Subjects with more advanced gastric lesions had a significantly increased risk of progression to GC.

BACKGROUND : The effectiveness of endoscopic screening on gastric cancer has not been widely investigated in China and the screening interval of repeated screening has not been determined. METHODS : In a population-based prospective study, we included 375,800 individuals, 14,670 of whom underwent endoscopic screening (2012-2018). We assessed the associations between endoscopic screening and risk of incident gastric cancer and gastric cancer-specific mortality, and examined changes in overall survival and disease-specific survival following screening. The optimal screening interval for repeated endoscopy for early detection of gastric cancer was explored. RESULTS : Ever receiving endoscopic screening significantly decreased the risk of invasive gastric cancer (age- and sex-adjusted relative risk [RR] 0.69, 95 % confidence interval [CI] 0.52-0.92) and gastric cancer-specific mortality (RR 0.33, 95 %CI 0.20-0.56), particularly for noncardia gastric cancer. Repeated screening strengthened the beneficial effect on invasive gastric cancer-specific mortality of one-time screening. Among invasive gastric cancers, screening-detected individuals had significantly better overall survival (RR 0.18, 95 %CI 0.13-0.25) and disease-specific survival (RR 0.18, 95 %CI 0.13-0.25) than unscreened individuals, particularly for those receiving repeated endoscopy. For individuals with intestinal metaplasia or low grade intraepithelial neoplasia, repeated endoscopy at an interval of < 2 years, particularly within 1 year, significantly enhanced the detection of early gastric cancer, compared with repeated screening after 2 years ( P -trend = 0.02). CONCLUSION : Endoscopic screening prevented gastric cancer occurrence and death, and improved its prognosis in a population-based study. Repeated endoscopy enhanced the effectiveness. Screening interval should be based on gastric lesion severity., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Tight junctions (TJs) of brain microvascular endothelial cells (BMECs) play a pivotal role in maintaining the blood-brain barrier (BBB) integrity; however, precise regulation of TJs stability in response to physiological and pathological stimuli remains elusive. Here, using RNA immunoprecipitation with next-generation sequencing (RIP-seq) and functional characterization, we identify SNHG12, a long non-coding RNA (lncRNA), as being critical for maintaining the BBB integrity by directly interacting with TJ protein occludin. The interaction between SNHG12 and occludin is oxygen adaptive and could block Itch (an E3 ubiquitin ligase)-mediated ubiquitination and degradation of occludin in human BMECs. Genetic ablation of endothelial Snhg12 in mice results in occludin reduction and BBB leakage and significantly aggravates hypoxia-induced BBB disruption. The detrimental effects of hypoxia on BBB could be alleviated by exogenous SNHG12 overexpression in brain endothelium. Together, we identify a direct TJ modulator lncRNA SNHG12 that is critical for the BBB integrity maintenance and oxygen adaption., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Lettuce (Lactuca sativa L.), one of the most economically important leaf vegetables, exhibits early bolting under high-temperature conditions. Early bolting leads to loss of commodity value and edibility, leading to considerable loss and waste of resources. However, the initiation and molecular mechanism underlying early bolting induced by high temperature remain largely elusive., Results: In order to better understand this phenomenon, we defined the lettuce bolting starting period, and the high temperature (33 °C) and controlled temperature (20 °C) induced bolting starting phase of proteomics is analyzed, based on the iTRAQ-based proteomics, phenotypic measurement, and biological validation by RT-qPCR. Morphological and microscopic observation showed that the initiation of bolting occurred 8 days after high-temperature treatment. Fructose accumulated rapidly after high-temperature treatment. During initiation of bolting, of the 3305 identified proteins, a total of 93 proteins exhibited differential abundances, 38 of which were upregulated and 55 downregulated. Approximately 38% of the proteins were involved in metabolic pathways and were clustered mainly in energy metabolism and protein synthesis. Furthermore, some proteins involved in sugar synthesis were differentially expressed and were also associated with energy production., Conclusions: This report is the first to report on the metabolic changes involved in the initiation of bolting in lettuce. Our study suggested that energy metabolism and ribosomal proteins are pivotal components during initiation of bolting. This study could provide a potential regulatory mechanism for the initiation of early bolting by high temperature, which could have applications in the manipulation of lettuce for breeding.

Objectives: Organotropism is primarily determined by tumor-derived exosomes. To date, the role of lung cancer cells-derived exosomes underlying the pre-metastatic niche formation is unclear., Materials and Methods: The animal models of retro-orbital and intra-ventricular injection were constructed to administrate lung cancer cells-derived exosomes. Cytokine array was used to screen the cytokines released from brain endothelium after internalization of lung cancer cells-derived exosomes. The cellular co-culture system was established to mimic microglia-vascular niche contained lung cancer cells-derived exosomes. The levels of Dkk-1 and the activities of microglia were analyzed by qRT-PCR, western blot and immunofluorescence. In vivo selections of highly brain metastatic cells were performed to analyze the direct interaction of lung cancer cells with microglia., Results: Animal studies demonstrated that there was a suppressive signal transferred from brain endothelium to microglia after internalization of lung cancer cells-derived exosomes into brain endothelium, which caused an absolutely less M1 phenotypic microglia and a relatively more M2 phenotypic microglia. Further results indicated that lung cancer cells-derived exosomes induced a release of endogenous Dkk-1 from brain endothelium, which rendered microglia to acquire a pro-tumorigenic feature in pre-metastatic niche. Subsequently, the declines of Dkk-1 in metastatic lung cancer cells removed the suppression on microglia and enhanced microglial activation in metastatic niche., Conclusion: Our findings shed a new light on the synergistic reaction of the different cells in "neurovascular units" toward the metastatic messages from lung cancer cells and provided a potential therapeutic pathway for lung cancer metastasis to brain., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Gan, Wang, He, Chen, Qin, Miao, Chen and Li.)

Tumor microenvironment (TME) plays a crucial role in the initiation and progression of lung adenocarcinoma (LUAD); however, there is still a challenge in understanding the dynamic modulation of the immune and stromal components in TME. In the presented study, we applied CIBERSORT and ESTIMATE computational methods to calculate the proportion of tumor-infiltrating immune cell (TIC) and the amount of immune and stromal components in 551 LUAD cases from The Cancer Genome Atlas (TCGA) database. The differentially expressed genes (DEGs) were analyzed by COX regression analysis and protein-protein interaction (PPI) network construction. Then, Bruton tyrosine kinase (BTK) was determined as a predictive factor by the intersection analysis of univariate COX and PPI. Further analysis revealed that BTK expression was negatively correlated with the clinical pathologic characteristics (clinical stage, distant metastasis) and positively correlated with the survival of LUAD patients. Gene Set Enrichment Analysis (GSEA) showed that the genes in the high-expression BTK group were mainly enriched in immune-related activities. In the low-expression BTK group, the genes were enriched in metabolic pathways. CIBERSORT analysis for the proportion of TICs revealed that B-cell memory and CD8+ T cells were positively correlated with BTK expression, suggesting that BTK might be responsible for the preservation of immune-dominant status for TME. Thus, the levels of BTK might be useful for outlining the prognosis of LUAD patients and especially be a clue that the status of TME transition from immune-dominant to metabolic activity, which offered an extra insight for therapeutics of LUAD., (Copyright © 2020 Bi, Wei, Qin and Li.)

The expression of contactin-associated protein 1 (Caspr1) in brain microvascular endothelial cells (BMECs), one of the major cellular components of the neurovascular unit (NVU), has been revealed recently. However, the physiological role of Caspr1 in BMECs remains unclear. We previously reported the nonamyloidogenic processing of amyloid protein precursor (APP) pathway in the human BMECs (HBMECs). In this study, we found Caspr1 depletion reduced the levels of soluble amyloid protein precursor α (sAPPα) in the supernatant of HBMECs, which could be rescued by expression of full-length Caspr1. Our further results showed that ADAM9, the α-secretase essential for processing of APP to generate sAPPα, was decreased in Caspr1-depleted HBMECs. The reduced sAPPα secretion in Caspr1-depleted HBMECs was recovered by expression of exogenous ADAM9. Then, we identified that Caspr1 specifically regulates the expression of ADAM9, but not ADAM10 and ADAM17, at transcriptional level by nuclear factor-κB (NF-κB) signaling pathway. Caspr1 knockout attenuated the activation of NF-κB and prevented the nuclear translocation of p65 in brain endothelial cells, which was reversed by expression of full-length Caspr1. The reduced sAPPα production and ADAM9 expression upon Caspr1 depletion were effectively recovered by NF-κB agonist. The results of luciferase assays indicated that the NF-κB binding sites are located at -859 bp to -571 bp of ADAM9 promoter. Taken together, our results demonstrated that Caspr1 facilitates sAPPα production by transcriptional regulation of α-secretase ADAM9 in brain endothelial cells., (Copyright © 2020 Tang, Liu, Li, Wang, Wang, Su, Fang, Qin, Wei, Zhao and Chen.)

Background: Colorectal cancer (CRC) is one of the most common malignancies worldwide., Aim: To explore the expression of microRNA miR-19a-3p and Forkhead box F2 (FOXF2) in patients with CRC and the relevant mechanisms., Methods: Sixty-two CRC patients admitted to the hospital were enrolled into the study group, and sixty healthy people from the same period were assigned to the control group. Elbow venous blood was sampled from the patients and healthy individuals, and blood serum was saved for later analysis. MiR-19a-3p mimics, miR-19a-3p inhibitor, miR-negative control, small interfering-FOXF2, and short hairpin-FOXF2 were transfected into HT29 and HCT116 cells. Then quantitative polymerase chain reaction was performed to quantify the expression of miR-19a-3p and FOXF2 in HT29 and HCT116 cells, and western blot (WB) analysis was conducted to evaluate the levels of FOXF2, glycogen synthase kinase 3 beta (GSK-3β), phosphorylated GSK-3β (p-GSK-3β), β-catenin, p-β-catenin, α-catenin, N-cadherin, E-cadherin, and vimentin. The MTT, Transwell, and wound healing assays were applied to analyze cell proliferation, invasion, and migration, respectively, and the dual luciferase reporter assay was used to determine the correlation of miR-19a-3p with FOXF2., Results: The patients showed high serum levels of miR-19a-3p and low levels of FOXF2, and the area under the curves of miR-19a-3p and FOXF2 were larger than 0.8. MiR-19a-3p and FOXF2 were related to sex, tumor size, age, tumor-node-metastasis staging, lymph node metastasis, and differentiation of CRC patients. Silencing of miR-19a-3p and overexpression of FOXF2 suppressed the epithelial-mesenchymal transition, invasion, migration, and proliferation of cells. WB analysis revealed that silencing of miR-19a-3p and FOXF2 overexpression significantly suppressed the expression of p-GSK-3β, β-catenin, N-cadherin, and vimentin; and increased the levels of GSK-3β, p-β-catenin, α-catenin, and E-cadherin. The dual luciferase reporter assay confirmed that there was a targeted correlation of miR-19a-3p with FOXF2. In addition, a rescue experiment revealed that there were no differences in cell proliferation, invasion, and migration in HT29 and HCT116 cells co-transfected with miR-19a-3p-mimics+sh-FOXF2 and miR-19a-3p-inhibitor+si-FOXF2 compared to the miR-negative control group., Conclusion: Inhibiting miR-19a-3p expression can upregulate the FOXF2-mediated Wnt/β-catenin signaling pathway, thereby affecting the epithelial-mesenchymal transition, proliferation, invasion, and migration of cells. Thus, miR-19a-3p is likely to be a therapeutic target in CRC., Competing Interests: Conflict-of-interest statement: The authors declare no conflicts of interest., (©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.)

Contactin-associated protein 1 (CASPR1 or CNTNAP1) was recently reported to be expressed in brain microvascular endothelial cells (BMECs), the major component of the blood-brain barrier. To investigate CASPR1's physiological role in BMECs, here we used CASPR1 as a bait in a yeast two-hybrid screen to identify CASPR1-interacting proteins and identified the β3 subunit of Na + /K + -ATPase (ATP1B3) as a CASPR1-binding protein. Using recombinant and purified CASPR1, RNAi, GST-pulldown, immunofluorescence, immunoprecipitation, and Na + /K + -ATPase activity assays, we found that ATP1B3's core proteins, but not its glycosylated forms, interact with CASPR1, which was primarily located in the endoplasmic reticulum of BMECs. CASPR1 knockdown reduced ATP1B3 glycosylation and prevented its plasma membrane localization, phenotypes that were reversed by expression of full-length CASPR1. We also found that the CASPR1 knockdown reduces the plasma membrane distribution of the α1 subunit of Na + /K + -ATPase, which is the major component assembled with ATP1B3 in the complete Na + /K + -ATPase complex. The binding of CASPR1 with ATP1B3, but not the α1 subunit, indicated that CASPR1 binds with ATP1B3 to facilitate the assembly of Na + /K + -ATPase. Furthermore, the activity of Na + /K + -ATPase was reduced in CASPR1-silenced BMECs. Interestingly, shRNA-mediated CASPR1 silencing reduced glutamate efflux through the BMECs. These results demonstrate that CASPR1 binds with ATP1B3 and thereby contributes to the regulation of Na + /K + -ATPase maturation and trafficking to the plasma membrane in BMECs. We conclude that CASPR1-mediated regulation of Na + /K + -ATPase activity is important for glutamate transport across the blood-brain barrier., (© 2019 Zhang et al.)

Salmonella effectors translocated into epithelial cells contribute to the pathogenesis of infection. They mediate epithelial cell invasion and subsequent intracellular replication. However, their functions in vivo have not been well-identified. In this study, we uncovered a role for Salmonella outer protein B (SopB) in modulating necroptosis to facilitate bacteria escape epithelial cell and spread to systemic sites through a Salmonella -induced colitis model. Mice infected with SopB deleted strain Δ sopB displayed increased severity to colitis, reduced mucin expression and increased bacterial translocation. In vitro study, we found there was an increased goblet cell necroptosis following Δ sopB infection. Consistently, mice infected with Δ sopB had a strong upregulation of mixed lineage kinase domain-like (MLKL) phosphorylation. Deletion of MLKL rescued severity of tissue inflammatory, improved mucin2 expression and abolished the increased bacterial translocation in mice infected with Δ sopB . Intriguingly, the expression of sopB in LS174T cells was downregulated. The temporally regulated SopB expression potentially switched the role from epithelial cell invasion to bacterial transmission. Collectively, these results indicated a role for SopB in modulating the onset of necroptosis to increased bacteria pathogenesis and translocated to systemic sites.

The maintenance of intestinal tissue homeostasis is vital for the resistance against inflammatory bowel diseases (IBDs). Necroptosis is identified as an alternative mode of regulated cell death, which plays a pivotal role in tissue homeostasis. Thus, the roles of RIP3-mediated necroptosis in intestinal inflammation have been extensively studied. However, the biological implications of the mixed lineage kinase-like protein (MLKL), a molecule downstream of RIP3 in gut remain unclear. In this study, the role of MLKL in DSS-induced colitis was examined, and the contribution of gut microbiota was also determined. Compared with non-littermate WT mice, the survival rate, clinical score, intestinal damage and intestinal mucosal barrier integrity of non-littermate MLKL-deficient mice are significantly improved. MLKL deficiency prevents inflammatory cytokines production and MAPK signaling activation. Hence, MLKL deficiency inhibits DSS-induced colitis. Moreover, we proved that DSS susceptibility difference between two genotypes is not driven by intestinal microbiota based on the co-housing of two non-littermate genotypes and qPCR detection of fecal dominant bacterial taxa., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Small cell lung cancer (SCLC) is the most aggressive histologic subtype of lung cancer, with a strong predilection for early brain metastases. Despite efforts and advances in new therapeutics for SCLC, the prognosis of patients with SCLC with brain metastases is consistently poor. Therefore, a better understanding of the mechanisms of SCLC brain metastasis is important in improving current treatments. In this study, elevated S100A16 levels were associated with SCLC brain metastases, which was a possible secondary event arising from the brain metastatic microenvironment. Using an in vitro cell coculture system, we found that the coculturing of SCLC cells with human brain microvascular endothelial cells (HBMECs) led to an increased expression of S100A16 in SCLC cells. Conversely, treatment of HBMECs with GW4869, an inhibitor of exosome release, significantly blocked this effect in the cocultured SCLC cells. Alternatively, the results from Western blot analyses and immunofluorescence indicated that the HBMEC exosomes purified by ultracentrifugation also induced the elevation and translocation from the cytoplasm to the nucleus of S100A16 in the recipient SCLC cells. The inhibition experiments demonstrated that elevated S100A16 contributed a benefit of HBMEC exosomes for the survival of the recipient SCLC cells under stress. Moreover, the elevation of S100A16 in SCLC cells prevented the loss of mitochondrial membrane potential (Δψm) and enhanced resistance to apoptosis under stressful conditions, which were determined by Annexin V/propidium iodide and JC-1 assay. Further results showed that the S100A16-mediated protective effect was caused by the presence of an important element in Δψm, prohibitin (PHB)-1, a protein in the mitochondrial inner membrane. Conversely, the delivery of PHB-1 siRNAs into S100A16 overexpressing SCLC cells weakened these protective effects. Our findings suggest that elevated S100A16 plays an active role in facilitating the survival of SCLC cells through modulating the mitochondrial function, identifying S100A16 as an important potential target in SCLC brain metastasis.-Xu, Z.-H., Miao, Z.-W., Jiang, Q.-Z., Gan, D.-X., Wei, X.-G., Xue, X.-Z., Li, J.-Q., Zheng, F., Qin, X.-X., Fang, W.-G., Chen, Y.-H., Li. B. Brain microvascular endothelial cell exosome-mediated S100A16 up-regulation confers small cell lung cancer cell survival in brain.

Bolting is a key process in the growth and development of lettuce ( Lactuca sativa L.). A high temperature can induce early bolting, which decreases both the quality and production of lettuce. However, knowledge of underlying lettuce bolting is still lacking. To better understand the molecular basis of bolting, a comparative proteomics analysis was conducted on lettuce stems, during the bolting period induced by a high temperature (33 °C) and a control temperature (20 °C) using iTRAQ-based proteomics, phenotypic measures, and biological verifications using qRT-PCR and Western blot. The high temperature induced lettuce bolting, while the control temperature did not. Of the 5454 identified proteins, 619 proteins presented differential abundance induced by high-temperature relative to the control group, of which 345 had an increased abundance and 274 had a decreased abundance. Proteins with an abundance level change were mainly enriched in pathways associated with photosynthesis and tryptophan metabolism involved in auxin (IAA) biosynthesis. Moreover, among the proteins with differential abundance, proteins associated with photosynthesis and tryptophan metabolism were increased. These findings indicate that a high temperature enhances the function of photosynthesis and IAA biosynthesis to promote the process of bolting, which is in line with the physiology and transcription level of IAA metabolism. Our data provide a first comprehensive dataset for gaining novel understanding of the molecular basis underlying lettuce bolting induced by high temperature. It is potentially important for further functional analysis and genetic manipulation for molecular breeding to breed new cultivars of lettuce to restrain early bolting, which is vital for improving vegetable quality.

Oxygen activation plays a crucial role in many important chemical reactions such as oxidation of organic compounds and oxygen reduction. For developing highly active materials for oxygen activation, herein, we report an atomically dispersed Pt on WO 3 nanoplates stabilized by in situ formed amorphous H 2 WO 4 out-layer and the mechanism for activating molecular oxygen. Experimental and theoretical studies demonstrate that the isolated Pt atoms coordinated with oxygen atoms from [WO 6 ] and water of H 2 WO 4 , consequently leading to optimized surface electronic configuration and strong metal-support interaction (SMSI). In exemplified reactions of butanone oxidation sensing and oxygen reduction, the atomic Pt/WO 3 hybrid exhibits superior activity than those of Pt nanoclusters/WO 3 and bare WO 3 as well as enhanced long-term durability. This work will provide insight into the origin of activity and stability for atomically dispersed materials, thus promoting the development of highly efficient and durable single atom-based catalysts., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Previous studies have demonstrated the effects of sclerostin antibody (Scl-Ab) and parathyroid hormone (1-34, PTH) on healing in osteoporosis; however, reports about the combined effects of Scl-Ab plus PTH on osteoporosis are limited. This study was designed to investigate the impact of combined treatment with Scl-Ab and PTH on osteoporosis healing in ovariectomized (OVX) rats. After bilateral ovariectomy, 12 weeks were allowed to pass for the establishment of standard conditions for osteoporosis in animal models. The rats then randomly received a vehicle (control), Scl-Ab (25 mg/kg body weight, twice weekly), PTH (60 μg/kg, three times per week) or PTH plus Scl-Ab until death at 12 weeks. The blood and distal femurs of the rats were harvested for evaluation. The results of treatment for osteoporosis were evaluated by serum analysis, histology, microcomputed tomography (micro-CT) and biomechanical tests. Results from this study indicated that PTH + Scl-Ab had stronger effects on the prevention and treatment of osteoporosis than either of the monotherapies in OVX rats. The PTH + Scl-Ab produced the strongest effects on bone volume fraction (BV/TV), bone trabecular thickness (Tb.Th), trabecular number (Tb.N) and trabecular spacing (Tb.Sp), bone mineral density (BMD) and strength of distal femurs and increased the levels of procollagen type I N‑terminal propeptide (PINP) and osteocalcin. In contrast, monotherapy with PTH or Scl-Ab showed no differences between treated groups in the assessment of the metaphysis of contralateral femurs by histology, serum, biomechanical tests and micro-CT. These results seem to indicate that Scl-Ab plus PTH has an additive effect on osteoporosis in OVX rats.

Escherichia coli is the leading cause of neonatal Gram-negative bacterial meningitis, but the pathogenesis of E. coli meningitis remains elusive. E. coli penetration of the blood-brain barrier (BBB) is the critical step for development of meningitis. Here, we identify Caspr1, a single-pass transmembrane protein, as a host receptor for E. coli virulence factor IbeA to facilitate BBB penetration. Genetic ablation of endothelial Caspr1 and blocking IbeA-Caspr1 interaction effectively prevent E. coli penetration into the brain during meningitis in rodents. IbeA interacts with extracellular domain of Caspr1 to activate focal adhesion kinase signaling causing E. coli internalization into the brain endothelial cells of BBB. E. coli can invade hippocampal neurons causing apoptosis dependent on IbeA-Caspr1 interaction. Our results indicate that E. coli exploits Caspr1 as a host receptor for penetration of BBB resulting in meningitis, and that Caspr1 might be a useful target for prevention or therapy of E. coli meningitis.

Objectives: To develop a method to screen and quantify 10 common herbicides （paraquat, diquat, glyphosate, glufosinate, cyanazine, atrazine, metazachlor, acetochlor, chlorsulfuron, and metsulfuron） in blood., Methods: With acetonitrile-water solution [ V （acetonitrile）∶ V （water）=3∶1] as protein precipitant, 10 common herbicides in blood were detected using ultra-high performance liquid chromatography-high resolution mass spectrometry （UPLC-HRMS）., Results: All the 10 herbicides had good linearity in their linear range （coefficient of determination R 2 ≥0.993）, with the recovery rates 67.4%-111.9%, the relative standard deviations 1.5%-10.8%, the accuracies 85.1%-106.1%, intra-day precisions 2.7%-13.5%, and inter-day precisions 3.3%-13.3%., Conclusions: This method is easy to operate with high recovery rates. It enables rapid and accurate qualitative screening and quantitative analysis of various herbicides in blood simultaneously., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

The present study aimed to compare polyphenols among red lettuce cultivars and identify suitable cultivars for the development and utilization of healthy vegetables. Polyphenols, mineral elements, and antioxidant activity were analyzed in the leaves of six red pigmented lettuce ( Lactuca sativa L.) cultivars; thereafter, we assessed the anti-tumor effects of cultivar B-2, which displayed the highest antioxidant activity. Quadrupole-Orbitrap mass spectrometry analysis revealed four classes of polyphenols in these cultivars. The composition and contents of these metabolites varied significantly among cultivars and primarily depended on leaf color. The B-2 cultivar had the highest antioxidant potential than others because it contained the highest levels of polyphenols, especially anthocyanin, flavone, and phenolic acid; furthermore, this cultivar displayed anti-tumor effects against the human lung adenocarcinoma cell line A549, human hepatoma cell line Bel7402, human cancer colorectal adenoma cell line HCT-8, and HT-29 human colon cancer cell line. Hence, the new red-leaf lettuce cultivar B-2 has a distinct metabolite profile, with high potential for development and utilization of natural phytochemical and mineral resources in lettuces and can be used as a nutrient-dense food product., Competing Interests: The authors declare no conflict of interest.

The intestinal mucosal barrier is critical for host defense against pathogens infection. Here, we demonstrate that the mixed lineage kinase-like protein (MLKL), a necroptosis effector, promotes intestinal epithelial barrier function by enhancing inflammasome activation. MLKL -/- mice were more susceptible to Salmonella infection compared with wild-type counterparts, with higher mortality rates, increased body weight loss, exacerbated intestinal inflammation, more bacterial colonization, and severe epithelial barrier disruption. MLKL deficiency promoted early epithelial colonization of Salmonella prior to developing apparent intestinal pathology. Active MLKL was predominantly expressed in crypt epithelial cells, and experiments using bone marrow chimeras found that the protective effects of MLKL were dependent on its expression in non-hematopoietic cells. Intestinal mucosa of MLKL -/- mice had impaired caspase-1 and gasdermin D cleavages and decreased interleukin (IL)-18 release. Moreover, administration of exogenous recombinant IL-18 rescued the phenotype of increased bacterial colonization in MLKL -/- mice. Thus, our results uncover the role of MLKL in enhancing inflammasome activation in intestinal epithelial cells to inhibit early bacterial colonization.

Objective: Platelet-rich plasma (PRP) has been reported to alleviate degenerative pathological damage to joint cartilage. This study aimed to investigate the effect of PRP on Wnt/β-catenin signaling in rabbit chondrocytes., Methods: Using 3-month-old New Zealand white rabbits, PRP was prepared from venous blood, and chondrocytes were cultured from knee joint cartilage and identified by staining for type II collagen and proteoglycan. The effects of PRP on chondrocyte viability were measured. The chondrocytes were divided into 5 groups: control, IL-1β, PRP (100-fold dilution), Dkk-1 (100ng/mL) and Dkk-1+PRP. The IL-1β, PRP, Dkk-1 and Dkk-1+PRP groups were treated with interleukin (IL)-1β (50μL, 10μg/mL) for24h. Chondrocyte morphology was observed by electron microscopy. Levels of carboxy terminal peptide (CTX-II) and cartilage oligomeric matrix protein (COMP) in culture media were measured by ELISA. Wnt-1, β-catenin and GSK-3β mRNA and protein expression were determined by RT-PCR and western blot respectively., Results: PRP enhanced chondrocyte proliferation. Chondrocytes in the IL-1β group showed ultrastructural abnormalities that were less pronounced in the PRP, Dkk-1 and Dkk-1+PRP groups. CTX-II and COMP concentrations were higher in the IL-1β group than in the control, PRP, Dkk-1 and Dkk-1+PRP groups (P<0.05). The IL-1β group had higher mRNA and protein Wnt1 and β-catenin levels and lower GSK-3β levels than the control, PRP, Dkk-1 and Dkk-1+PRP groups (P<0.05)., Conclusion: PRP may protect chondrocytes activated by IL-1β via inhibiting Wnt/β-catenin signaling., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: To determine the most cost-effective modality for breast cancer screening in women living in Shanghai. Methods: A Markov model for breast cancer was redeveloped based on true effect which was derived from a project for detection of women at high risk of breast cancer and an organized breast cancer screening program conducted simultaneously in Minhang district, Shanghai, during 2008 to 2012. Parameters of the model were derived from literatures. General principles related to cost-effectiveness analysis were used to compare the costs and effects of 12 different screening modalities in a simulated cohort involving 100 000 women aged 45 years. Incremental cost-effectiveness ratio (ICER) was used to determine the most cost-effective modality. Sensitivity analysis was conducted to evaluate how these factors affected the estimated cost-effectiveness. Results: The modality of biennial CBE followed by ultrasonic and mammography among those with positive CBE was observed as the most cost-effective one. The costs appeared as 182 526 Yuan RMB per life year gained and 144 386 Yuan RMB per quality adjusted life-year (QALY) saved, which were within the threshold of 2-3 times of local per capita Gross Domestic Product. Results from sensitivity analysis showed that, due to higher incidence rate of breast cancer in Shanghai, the cost per QALY would be 64 836 Yuan RMB lower in Shanghai than the average level in China. Conclusion: Our research findings showed that the biennial CBE program followed by ultrasonic and mammography for those with positive CBE results might serve as the optimal breast cancer screening modality for Chinese women living in Shanghai, and thus be widely promoted in this population elsewhere.

Breast cancer adversely affects the health status of women; therefore, the prevention and treatment of breast cancer is of critical importance. Lycopene is known to possess several biological effects such as removal of free radicals, alleviation of biological oxidative injury, and inhibition of tumor growth. In this study, we aimed to illustrate the effect of lycopene on tumor cell proliferation and modulation of cancer progression as well as its possible underlying mechanisms in human breast carcinoma cell line MCF-7 in vitro. MCF-7 cells were treated with different lycopene concentrations for 24, 48, and 72 h. Light field microscopy was used to observe cell morphology. MTT assay was used to determine the effect of lycopene on MCF-7 proliferation. Flow cytometry was employed to evaluate cell apoptosis. Real-time quantitative polymerase chain reaction was performed to detect the expression of p53 and Bax. Under microscopic examination, the untreated MCF-7 cells appeared to have a diamond or polygonal shape. Lycopene treatment resulted in cell shrinkage and breakage, whose severity increased in a dose and duration dependent manner. In addition, reduced cell proliferation and increased apoptosis (P < 0.05) were observed using MTT assay and flow cytometry, respectively. Moreover, lycopene could also upregulate the expression of p53 and Bax mRNAs in MCF-7 cells. In conclusion, lycopene inhibits proliferation and facilitates apoptosis of MCF-7 cells in vitro, possibly by regulating the expression of p53 and Bax.

Amyloid-β (Aβ), the major component of neuritic plaques in Alzheimer's disease (AD), is derived from sequential proteolytic cleavage of amyloid protein precursor (APP) by secretases. In this study, we found that cystatin C (CysC), a natural cysteine protease inhibitor, is able to reduce Aβ40 secretion in human brain microvascular endothelial cells (HBMEC). The CysC-induced Aβ40 reduction was caused by degradation of β-secretase BACE1 through the ubiquitin/proteasome pathway. In contrast, we found that CysC promoted secretion of soluble APPα indicating the activated non-amyloidogenic processing of APP in HBMEC. Further results revealed that α-secretase ADAM10, which was transcriptionally upregulated in response to CysC, was required for the CysC-induced sAPPα secretion. Knockdown of SIRT1 abolished CysC-triggered ADAM10 upregulation and sAPPα production. Taken together, our results demonstrated that exogenously applied CysC can direct amyloidogenic APP processing to non-amyloidgenic pathway in brain endothelial cells, mediated by proteasomal degradation of BACE1 and SIRT1-mediated ADAM10 upregulation. Our study unveils previously unrecognized protective role of CysC in APP processing.

The association of microglia with brain vasculature during development and the reduced brain vascular complexity in microglia-deficient mice suggest the role of microglia in cerebrovascular angiogenesis. However, the underlying molecular mechanism remains unclear. Here, using an in vitro angiogenesis model, we found the culture supernatant of BV2 microglial cells significantly enhanced capillary-like tube formation and migration of brain microvascular endothelial cells (BMECs). The expression of angiogenic factors, ephrin-A3 and ephrin-A4, were specifically upregulated in BMECs exposed to BV2-derived culture supernatant. Knockdown of ephrin-A3 and ephrin-A4 in BMECs by siRNA significantly attenuated the enhanced angiogenesis and migration of BMECs induced by BV2 supernatant. Our further results indicated that the ability of BV2 supernatant to promote endothelial angiogenesis was caused by the soluble tumor necrosis factor α (TNF-α) released from BV2 microglial cells. Moreover, the upregulations of ephrin-A3 and ephrin-A4 in BMECs in response to BV2 supernatant were effectively abolished by neutralization antibody against TNF-α and TNF receptor 1, respectively. The present study provides evidence that microglia upregulates endothelial ephrin-A3 and ephrin-A4 to facilitate in vitro angiogenesis of brain endothelial cells, which is mediated by microglia-released TNF-α., (© 2014 Wiley Periodicals, Inc.)

The catalytic dehydration of fructose to 5-hydroxymethylfurfural (HMF) was investigated by using various rare earth metal trifluoromethanesulfonates, that is, Yb(OTf)(3), Sc(OTf)(3), Ho(OTf)(3), Sm(OTf)(3), Nd(OTf)(3) as catalysts in DMSO. It is found that the catalytic activity increases with decreasing ionic radius of rare earth metal cations. Among the examined catalysts, Sc(OTf)(3) exhibits the highest catalytic activity. Fructose conversion of 100% and a HMF yield of 83.3% are obtained at 120°C after 2h by using Sc(OTf)(3) as the catalyst. Moreover, the catalytic dehydration of fructose was also carried out in different solvents, for example, DMA, 1,4-dioxane, and a mixture of PEG-400 and water. The results show that among the solvents DMSO is the most efficient in promoting the dehydration of fructose to HMF, and no rehydration byproducts such as levulinic acid and formic acid are detected., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objective: To investigate the prevalence of various mental disorders of suicide attempters and analyze the clinical features of suicide attempters with mental disorders., Methods: The investigators randomly selected four Class III general hospitals from different parts of Shenyang and collected 239 suicide attempters over 15 years old at emergency room. When the conditions of suicide attempters improved after rescue, the investigators studied by suicide general table, self-injury questionnaire, Hamilton Depression Rating Scale for Depression-24 and Structure Clinical Interview for DSM-IV Axis I Disorders-Patient Edition., Results: The overall prevalence of mental disorders in attempted suicides was 69.46% while self-injury, one of the highest prevalent mood disorders, accounted for 48.12%. During the year before suicide, only 7.23% of the suicide attempters with mental disorders consulted a psychologist or psychiatrist, and took anti-psychosis drugs, anti-depression or anti-anxiety drugs. Suicide attempters with mental disorders often committed suicide less impulsively. And their purpose was to relieve themselves and reduce the burden of others so that the rate of self-help was lower after their injuries occurred; suicide attempters with mental disorders had more obvious symptoms. And their degrees of depression were greater (P < 0.05) than ones without mental disorders., Conclusion: The prevalence of mental disorders at emergency rooms in general hospitals is high in suicide attempts, but the pre-suicide consulting rate remains so low. The depressive components of mental disorders are most directly related to suicidal behaviors of suicide attempters.

Objective: To establish a three-dimensional finite element model of mandibular distraction osteogenesis (DO) in order to study the influence of distraction orientations to mandibular DO., Methods: By using the two finite element models, Von Mises stress and the displacement under different loads were measured., Results: The maximum stress in the distract equipment paralleled to the mandibular corpus was two times of that when the distract equipment paralleled to the sagittal axis. Von Mises stress concentration mainly occurred in the loading position and the condylar ante inferior. This phenomenon may lead to partial bone resorption, consequently lead to screw loose and affect the stability of distraction device. When the displacement increased in the model, the maximum stress and displacement showed linear relation., Conclusion: The counterforce produced by the device makes lateral displacement in tail. The reaction force could be reduced to a minimum degree when the traction device parallel to the sagittal axis. This study provides theoretical basis for the position of distract equipment and distraction orientations in clinical application.

Mussel byssal threads contain unusual block copolymer-like proteins that combine collagen with flanking domains that resemble silk-fibroin (preCol-D) or elastin (preCol-P). These are distributed in complementary gradients along the length of the threads and as precursors in the mussel foot. We discuss a 76-kDa precursor, preCol-NG, from a cDNA library of the foot where it has no gradient but rather is distributed evenly along the distal to proximal axis. A pepsin-resistant fragment of preCol-NG has been confirmed in byssal threads. Like preCol-D and -P, this protein has a central collagenous domain, flanking domains, an acidic patch, and histidine-rich termini. The flanking domains of preCol-NG resemble the glycine-rich proteins of plant cell walls with tandem XGlyn repeats where X denotes alanine, leucine, or asparagine but not proline. Similarity with the (glycine-alanine) repeats and poly(alanine) runs of arthropod silks also exists. Based on available evidence, a model of preCol axial assembly is proposed in which preCol-NG functions as a mediator between preCol-D/-P molecules. This is consistent with the observed progression of mechanical properties in byssal threads.

The byssal collagens of marine mussels are extracorporeal collagens that function in byssal threads under tension. Each byssal thread resembles a shock absorber in its mechanical design: it is strong and stiff at one end and pliably elastic at the other. Primary structures of three of these collagens (preCols), deduced from cDNAs, reveal signal peptide sequences, but no N-glycosylation sites or propeptides typical of procollagens. The collagen domain (40-50 kDa) represents roughly half the mass of the mature molecules and is distinguished by its central location, abundant Gly-Gly-X repeats, and "flaws" (usually Gly deletions). Flanking the collagen domains on both sides are structural domains that resemble elastin in preCol-P, spider drag-line silk in preCol-D, and Gly-rich cell wall proteins in preCol-NG. Not surprisingly, studies of preCol distribution in byssal threads suggest preCol-P enhancement in the elastic proximal portion, while preCol-D predominates in the stiffer distal portion. PreCol-NG, in contrast, is evenly distributed. Although no data are yet available on the fibrillogenesis and cross-linking of the preCols, the quarter-stagger assembly of fibrillar interstitial collagens does not pertain since preCols lack the terminal peptides of tropocollagen. Metal-binding by histidines may mediate the initial inter- and intramolecular stabilization of preCols in the byssus.

The primary structure of the alpha-chain of preCol-D (molecular mass = 80 kDa), a tanned collagenous protein predominating in the distal portion of the byssal threads of the mussel Mytilus edulis, was deduced from cDNA to encode an unprecedented natural block copolymer with three major domain types: a central collagen domain flanked by fibroin-like domains and followed by histidine-rich termini. The fibroin-like domains have sequence motifs that strongly resemble the crystalline polyalanine-rich and amorphous glycine-rich regions of spider dragline silk fibroins. The terminal regions resemble the histidine-rich domains of a variety of metal-binding proteins. The silk domains may toughen the collagen by increasing its strength and extensibility. PreCol-D expression is limited to the mussel foot, which contains a longitudinal gradient of preCol-D mRNA. This gradient increases linearly in the proximal to distal direction and reaches a maximum just before the distal depression of the foot.

To adhere to solid surfaces, marine mussels produce byssal threads, each of which is a stiff tether at one end and a shock absorber with 160 percent extensibility at the other end. The elastic extensibility of proximal byssus is extraordinary given its construction of collagen and the limited extension (less than 10 percent) of most collagenous materials. From the complementary DNA, we deduced that the primary structure of a collagenous protein (preCol-P) predominating in the extensible proximal portion of the threads encodes an unprecedented natural block copolymer with three major domain types: a central collagen domain, flanking elastic domains, and histidine-rich terminal domains. The elastic domains have sequence motifs that strongly resemble those of elastin and the amorphous glycine-rich regions of spider silk fibroins. Byssal thread extensibility may be imparted by the elastic domains of preCol-P.

A group of 140 cotton textile workers from Shanghai, Shandong, Guangxi, and Beijing have had their chest radiographs taken using similar requirements. Most had come from the preparatory departments of cotton mills and had a history of exposure to cotton dust for at least 20 years. As controls, 140 healthy individuals with no dust exposure were matched with respect to sex, age, and smoking history. All the radiographs were read according to the ILO International Pneumoconiosis Classification, and the manifestations belonging to categories 0/0 and 0/1 were grouped as "normal," whereas categories 1/0, 1/1, and 1/2 and above as "abnormal." There was no significant difference in X-ray abnormalities between cotton textile workers and controls (P greater than 0.05). But when the data on the cotton textile workers and controls were combined, an appreciable difference in the incidence of radiographic abnormalities was found between smokers and non-smokers (P less than 0.001). Cotton dust exposure may induce nonspecific interstitial pulmonary changes, but these changes were exaggerated by cigarette smoking. These two factors appeared to have an additive effect on the pulmonary X-ray findings.