SZT2 dictates GATOR control of mTORC1 signalling

Mechanistic target of rapamycin complex 1 (TORC1) integrates nutrient signals to control cell growth and organismal homeostasis across eukaryotes. The evolutionarily conserved GATOR complex regulates mTORC1 signalling through Rag GTPases, and GATOR1 displays GTPase activating protein (GAP) activity for RAGA and RAGB (RAGA/B) and GATOR2 has been proposed to be an inhibitor of GATOR1. Furthermore, the metazoan-specific SESN proteins function as guanine nucleotide dissociation inhibitors (GDIs) for RAGA/B, and interact with GATOR2 with unknown effects. Here we show that SZT2 (seizure threshold 2), a metazoan-specific protein mutated in epilepsy, recruits a fraction of mammalian GATOR1 and GATOR2 to form a SZT2-orchestrated GATOR (SOG) complex with an essential role in GATOR- and SESN-dependent nutrient sensing and mTORC1 regulation. The interaction of SZT2 with GATOR1 and GATOR2 was synergistic, and an intact SOG complex was required for its localization at the lysosome. SZT2 deficiency resulted in constitutive mTORC1 signalling in cells under nutrient-deprived conditions and neonatal lethality in mice, which was associated with failure to inactivate mTORC1 during fasting. Hyperactivation of mTORC1 in SZT2-deficient cells could be partially corrected by overexpression of the GATOR1 component DEPDC5, and by the lysosome-targeted GATOR2 component WDR59 or lysosome-targeted SESN2. These findings demonstrate that SZT2 has a central role in dictating GATOR-dependent nutrient sensing by promoting lysosomal localization of SOG, and reveal an unexpected function of lysosome-located GATOR2 in suppressing mTORC1 signalling through SESN recruitment.

Clinical Study of NeuroRegen Scaffold Combined With Human Mesenchymal Stem Cells for the Repair of Chronic Complete Spinal Cord Injury

Regeneration of damaged neurons and recovery of sensation and motor function after complete spinal cord injury (SCI) are challenging. We previously developed a collagen scaffold, NeuroRegen, to promote axonal growth along collagen fibers and inhibit glial scar formation after SCI. When functionalized with multiple biomolecules, this scaffold promoted neurological regeneration and functional recovery in animals with SCI. In this study, eight patients with chronic complete SCI were enrolled to examine the safety and efficacy of implanting NeuroRegen scaffold with human umbilical cord mesenchymal stem cells (hUCB-MSCs). Using intraoperative neurophysiological monitoring, we identified and surgically resected scar tissues to eliminate the inhibitory effect of glial scarring on nerve regeneration. We then implanted NeuroRegen scaffold loaded with hUCB-MSCs into the resection sites. No adverse events (infection, fever, headache, allergic reaction, shock, perioperative complications, aggravation of neurological status, or cancer) were observed during 1 year of follow-up. Primary efficacy outcomes, including expansion of sensation level and motor-evoked potential (MEP)-responsive area, increased finger activity, enhanced trunk stability, defecation sensation, and autonomic neural function recovery, were observed in some patients. Our findings suggest that combined application of NeuroRegen scaffold and hUCB-MSCs is safe and feasible for clinical therapy in patients with chronic SCI. Our study suggests that construction of a regenerative microenvironment using a scaffold-based strategy may be a possible future approach to SCI repair.

Expression of kisspeptin/kiss1r system in developing hypothalamus of female rat and the possible effects on reproduction development and maintenance

BACKGROUND

The kisspeptin/kiss1r system, expressed in the hypothalamic arcuate nucleus, has been proclaimed as one of the most powerful factors of the reproduction axis, according to recent researches in the reproductive field. The aim of this study was to ascertain the expression of kisspeptin, its receptor (kiss1r), and gonadotropin-releasing hormone (GnRH), and to explore the role on the development and maintenance of the reproductive function of developing female rats.

METHODS

Expressions of the kisspeptin/kiss1r system were examined by immunohistochemistry and Real time Quantitative PCR (qRT-PCR). Expressions of estradiol (E2), luteinizing hormone, and follicle-stimulating hormone were analyzed by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Expression of the kisspeptin/kiss1r system increased time dependently with aging, and their peak expression was demonstrated in the adult stage. GnRH showed a similar expression pattern to that of the kisspeptin/kiss1r system. ELISA results demonstrated that the E2, luteinizing hormone, and follicle-stimulating hormone secretion increased time dependently from infancy to prepuberty to puberty. However, E2 level decreased significantly in adult rats. Morphological changes of ovaries showed that primordial follicles, primary follicles, and growing follicle inhabited the dominant status in infancy, prepuberty, and puberty stages, respectively.

CONCLUSION

GnRH neurons may play an intermediate role in the activation and maintenance of the reproductive function regulated by the kisspeptin/kiss1r system, which may also indirectly regulate the serum level of luteinizing hormone, follicle-stimulating hormone, and E2.

Aerobic glycolysis promotes T helper 1 cell differentiation through an epigenetic mechanism

Aerobic glycolysis (the Warburg effect) is a metabolic hallmark of activated T cells and has been implicated in augmenting effector T cell responses, including expression of the proinflammatory cytokine interferon-γ (IFN-γ), via 3' untranslated region (3'UTR)-mediated mechanisms. Here, we show that lactate dehydrogenase A (LDHA) is induced in activated T cells to support aerobic glycolysis but promotes IFN-γ expression independently of its 3'UTR. Instead, LDHA maintains high concentrations of acetyl-coenzyme A to enhance histone acetylation and transcription of Ifng Ablation of LDHA in T cells protects mice from immunopathology triggered by excessive IFN-γ expression or deficiency of regulatory T cells. These findings reveal an epigenetic mechanism by which aerobic glycolysis promotes effector T cell differentiation and suggest that LDHA may be targeted therapeutically in autoinflammatory diseases.

Characterization of the Expression of the RNA Binding Protein eIF4G1 and Its Clinicopathological Correlation with Serous Ovarian Cancer

BACKGROUND

Ovarian cancer is the most lethal type of malignant tumor in gynecological cancers and is associated with a high percentage of late diagnosis and chemotherapy resistance. Thus, it is urgent to identify a tumor marker or a molecular target that allows early detection and effective treatment. RNA-binding proteins (RBPs) are crucial in various cellular processes at the post-transcriptional level. The eukaryotic translation initiation factor 4 gamma, 1(eIF4G1), an RNA-binding protein, facilitates the recruitment of mRNA to the ribosome, which is a rate-limiting step during the initiation phase of protein synthesis. However, little is known regarding the characteristics of eIF4G1 expression and its clinical significance in ovarian cancer. Therefore, we propose to investigate the expression and clinicopathological significance of eIF4G1 in ovarian cancer patients.

METHODS

We performed Real-time PCR in 40 fresh serous ovarian cancer tissues and 27 normal ovarian surface epithelial cell specimens to assess eIF4G1mRNA expression. Immunohistochemistry (IHC) was used to examine the expression of eIF4G1 at the protein level in 134 patients with serous ovarian cancer and 18 normal ovarian tissues. Statistical analysis was conducted to determine the correlation of the eIF4G1 protein levels with the clinicopathological characteristics and prognosis in ovarian cancer.

RESULTS

The expression of eIF4G1 was upregulated in serous ovarian cancer tissues at both the mRNA (P = 0.0375) and the protein (P = 0.0007) levels. The eIF4G1 expression was significantly correlated with the clinical tumor stage (P = 0.0004) and omentum metastasis (P = 0.024). Moreover, patients with low eIF4G1 protein expression had a longer overall survival time (P = 0.026).

CONCLUSIONS

These data revealed that eIF4G1 is markedly expressed in serous ovarian cancer and that upregulation of the eIF4G1 protein expression is significantly associated with an advanced tumor stage. Besides, the patients with lower expression of eIF4G1 tend to have a longer overall survival time. Thus, eIF4G1 may contribute to the occurrence and metastasis of ovarian cancer and can serve as a potential therapeutic target for the treatment of ovarian cancer.

[Clinical value of changes of SUVmax in series 18F-FDG PET/CT imaging before and after chemotherapy for non-small cell lung cancer]

Objective: To evaluate the clinical value of changes of maximum standardized uptake value (SUVmax) in series ¹⁸F-FDG PET/CT imaging before and after chemotherapy for non-small cell lung cancer. Methods: From July 2008 to July 2014, a total of 18 patients with pathological confirmed advanced NSCLC who received systemic chemotherapy were enrolled.¹⁸F-FDG PET/CT scans were performed before, 3-4 weeks after 2-4 cycles chemotherapy, 3-4 weeks after the end of chemotherapy for all patients, and added fourth scan for 3 patients 1 year later.The SUVmax of region of interesting was calculated.The histological diagnosis or clinical findings in a 36 months follow-up period served as the standard of control. Results: New metastases foci were found by ¹⁸F-FDG PET/CT scans before chemotherapy in 7 of 18 patients.The plans of chemotherapy for 5 patients were changed as therapeutic responses were evaluated according to changes of SUVmax.Targeted therapy was added for 2 patients after the end of chemotherapy.There was a statistically significant difference in outcome of survival analysis between patients performed PET/CT scans and non-performed (P<0.05). Conclusion: Changes of SUVmax in series ¹⁸F-FDG PET/CT imaging before and after chemotherapy could be used to evaluate therapeutic response and effectively predict survival in patients with advanced NSCLC.

Helium preconditioning protects the brain against hypoxia/ischemia injury via improving the neurovascular niche in a neonatal rat model

This study aimed to investigate whether helium preconditioning (He-PC) is able to exert neuroprotective effects via improving focal neurovascular niche in a neonatal rat hypoxia/ischemia (HI) brain injury model. Seven day old rat pups were divided into control group, HI group and He-PC group. HI was induced by exposure to 8% oxygen for 90min one day after preconditioning with 70% helium-30% oxygen for three 5-min periods. At 3 and 7 days, the brain was collected for the detection of inflammation related factors (tumor necrosis factor α [TNF-α], interleukin-1β [IL-1β], IL-10) and growth/neurotrophic factors (brain-derived neurotrophic factor [BDNF], basic fibroblast growth factor [bFGF] and nerve growth factor [NGF]); at 7 days, neurobehaviors were evaluated, and the brain was collected for the detection of mRNA expression of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) by PCR, protein expression of angiogenesis related molecules (VEGF, Ang-1, Tie-2 and Flt-1) by Western blotting and microvessel density (MCD) by immunohistochemistry for vWF. Results showed He-PC was able to reduce TNF-α and IL-1β, further increase IL-10, BDNF, bFGF and NGF, elevate the mRNA expression of VEGF and Ang-1, increase the protein expression of VEGF, Ang-1, Tie-2 and Flt-1, promote angiogenesis and improve neurobehaviors as compared to HI group. These findings suggest that He-PC may improve the post-stroke neurovascular niche to exert neuroprotective effects on neonatal HI brain injury.

TRIM66 overexpresssion contributes to osteosarcoma carcinogenesis and indicates poor survival outcome

TRIM66 belongs to the family of tripartite motif (TRIM)-containing proteins. Alterations in TRIM proteins have been implicated in several malignancies. This study was aimed at elucidating the expression and biological function of TRIM66 in osteosarcoma. Here, TRIM66 expression level was higher in osteosarcoma tissues than in normal tissues. High TRIM66 expression was correlated with high rate of local recurrence and lung metastasis, and short survival time. Then, we found that knockdown of TRIM66 in two osteosarcoma cell lines, MG63 and HOS, significantly inhibited cell proliferation and induced G1-phase arrest. Moreover, inhibition of TRIM66 in osteosarcoma cells significantly induced cell apoptosis, while remarkably inhibited cell migration, invasion as well as tumorigenicity in nude mice. Gene set enrichment analysis in Gene Expression Omnibus dataset revealed that apoptosis, epithelial-mesenchymal transition (EMT) and transforming growth factor-β (TGF-β) signaling pathway-related genes were enriched in TRIM66 higher expression patients, which was confirmed by western blot analysis in osteosarcoma cells with TRIM66 silenced. In conclusion, TRIM66 may act as an oncogene through suppressing apoptosis pathway and promoting TGF-β signaling in osteosarcoma carcinogenesis. TRIM66 may be a prognostic factor and potential therapeutic target in osteosarcoma.

Hyperbaric oxygen preconditioning protects the lung against acute pancreatitis induced injury via attenuating inflammation and oxidative stress in a nitric oxide dependent manner

This study aimed to investigate the protective effects of hyperbaric oxygen preconditioning (HBO-PC) on acute pancreatitis AP associated acute lung injury (ALI) and the potential mechanisms. Rats were randomly divided into sham group, AP group, HBO-PC + AP group and HBO-PC + L-NAME group. Rats in HBO-PC + AP group received HBO-PC once daily for 3 days, and AP was introduced 24 h after last HBO-PC. In HBO-PC + L-NAME group, L-NAME (40 mg/kg) was intraperitoneally injected before each HBO-PC. At 24 h after AP, the blood lipase and amylase activities were measured; the lung and pancreas were harvested for pathological examination; the bronchoalveolar lavage fluid was collected for the detection of lactate dehydrogenase (LDH) and proteins; inflammatory factors, superoxide dismutase (SOD) activity and malonaldehyde content were measured in the lung and blood; the Nrf2, SOD-1 and haem oxygenase-1 (HO-1) protein expression was measured in the lung. The lung nitric oxide (NO) and NO synthase activity increased significantly after HBO-PC. HBO-PC was able to reduce blood lipase and amylase activities, improve lung and pancreatic pathology, decrease LDH and proteins in BALF, inhibit the production of inflammatory factors, reduce malonaldehyde content and increase SOD activity in the lung and blood as well as increase protein expression of Nrf2, SOD-1 and HO-1 in the lung. However, L-NAME before HBO-PC significantly attenuated protective effects of HBO-PC. HBO-PC is able to protect the lung against AP induced injury by attenuating inflammation and oxidative stress in the lung via a NO dependent manner.

High-intensity focused ultrasound treatment of placenta accreta after vaginal delivery: a preliminary study

OBJECTIVE

To evaluate the safety and efficiency of high-intensity focused ultrasound (HIFU) in the treatment of placenta accreta after vaginal delivery.

METHODS

Enrolled into this study between September 2011 and September 2013 were 12 patients who had been diagnosed with placenta accreta following vaginal delivery and who had stable vital signs. All patients were treated using an ultrasound-guided HIFU treatment system. As indication of the effectiveness of the treatment we considered decreased vascular index on color Doppler imaging, decrease in size of residual placenta compared with pretreatment size on assessment by three-dimensional ultrasound with Virtual Organ Computer-aided Analysis, reduced signal intensity and degree of enhancement on magnetic resonance imaging and avoidance of hysterectomy following treatment. To assess the safety of HIFU treatment, we recorded side effects, hemorrhage, infection, sex steroid levels, return of menses and subsequent pregnancy. Patients were followed up in this preliminary study until December 2013.

RESULTS

The 12 patients receiving HIFU treatment had an average postpartum hospital stay of 6.8 days and an average period of residual placental involution of 36.9 days. HIFU treatment did not apparently increase the risk of infection or hemorrhage and no patient required hysterectomy. In all patients menstruation recommenced after an average of 80.2 days, and sex steroid levels during the middle luteal phase of the second menstrual cycle were normal. Two patients became pregnant again during the follow-up period.

CONCLUSION

This preliminary study suggests that ultrasound-guided HIFU is a safe and effective non-invasive method to treat placenta accreta patients after vaginal delivery who have stable vital signs and desire to preserve fertility. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

MicroRNA profile analysis of host cells before and after wild human rotavirus infection

Rotavirus infection is an important cause of acute gastroenteritis in children, but the interaction between rotavirus and host cells is not completely understood. We isolated a wildtype (wt) rotavirus strain, ZTR-68(P [8] G1), which is derived from an infant with diarrhea in southwest China in 2010. In this study, we investigated host cellular miRNA expression profiles changes in response to ZTR-68 in early stage of infection to investigate the role of miRNAs upon rotavirus infection. Differentially expressed miRNAs were identified by deep sequencing and qRT-PCR and the function of their targets predicted by Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation. A total of 36 candidate miRNAs were identified. Comparative analysis indicated that 29 miRNAs were significantly down-regulated and 7 were up-regulated after infection. The data were provided contrasting the types of microRNAs in two different permissive cell lines (HT29 and MA104). The target assays results showed that mml-miR-7 and mml-miR-125a are involved in anti-rotavirus and virus-host interaction in host cells. These results offer clues for identifying potential candidates in vector-based antiviral strategies. J. Med. Virol. 88:1497-1510, 2016. © 2016 Wiley Periodicals, Inc.

Dopaminergic neuron-like cells derived from bone marrow mesenchymal stem cells by Lmx1α and neurturin overexpression for autologous cytotherapy in hemiparkinsonian rhesus monkeys

Bone marrow-derived mesenchymal stem cells hold great potential for cytotherapeutics of neurodegenerative disorders, including Parkinson's disease. The neurotrophic factor neurturin can rescue dopaminergic neurons damaged during the disease process. Lmx1α can promote mesencephalic dopaminergic differentiation during embryogenesis. In this study, we tested a cytotherapeutic strategy combining NTN/Lmx1α gene therapy and cell transplantation to ameliorate disease progression in hemiparkinsonian rhesus. Rhesus BMSCs were prepared for autologous grafting by transfection with recombinant adenoviral vectors expressing secreted NTN and Lmx1α,and cultured in the presence of induce factors, particularly the Lmx1α regulatory factor sonic hedgehog, to guide dopaminergic differentiation. These induced rh-BMSCs exhibited gene/protein expression phenotypes resembling nigral dopaminergic neurons. They survived and retained dopaminergic function following stereotaxic injection into the MPTP-lesioned right-side substantia nigra as indicated by SPECT measurement of DAT activity. Injected cells preserved and supplemented the remaining endogenous population of dopamine neurons (TH-positive cell ipsilateral/contralateral ratio was 56.81% ± 7.28% vs. 3.86%±1.22% in vehicle-injected controls; p<0.05). Cell injection also partially restored motor function and reduce apomorphine-evoked rotation (p<0.05). Moreover, function recovery occurred earlier than in previous studies on injected BMSCs. Our findings demonstrate a promising strategy for restoration of PD-associated motor dysfunction by transplantation of autologous BMSCs overexpressing NTN/Lmx1α.

Increased oligomerization and phosphorylation of α-synuclein are associated with decreased activity of glucocerebrosidase and protein phosphatase 2A in aging monkey brains

Aging is associated with an increased risk for Parkinson's disease and dementia with Lewy bodies, in which α-synuclein (α-syn) oligomerization plays key pathogenic roles. Here, we show that oligomeric α-syn levels increase with age in the brain of cynomolgus monkeys and are accompanied by a decrease in the expression and activity of glucocerebrosidase (GCase), a lysosomal enzyme whose dysfunction is linked to accumulation of oligomeric α-syn. Besides, levels of α-syn phosphorylated at serine 129 (pS129 α-syn), a modification that promotes α-syn oligomerization also increase with age in the brain and is associated with a reduction in the activity of protein phosphatase 2A (PP2A), an enzyme that facilitates α-syn dephosphorylation. The inverse relationship between levels of oligomeric α-syn and pS129 α-syn and activity of GCase and PP2A was more evident in brain regions susceptible to neurodegeneration (i.e., the striatum and hippocampus) than those that are less vulnerable (i.e., cerebellum and occipital cortex). In vitro experiments showed that GCase activity was more potently inhibited by oligomeric than by monomeric α-syn in the lysosome-enriched fractions isolated from brain tissues and cultured neuronal cells. Inhibition of GCase activity induced an elevation of oligomeric α-syn levels, which was shown to increase pS129 α-syn levels and reduce PP2A activity in cultured neuronal cells. The alterations in oligomeric and pS129 α-syns and their association with GCase and PP2A in aging brains may explain the vulnerability of certain brain regions to neurodegeneration in Parkinson's disease and dementia with Lewy bodies.

Anchoring vignettes in the Health and Retirement Study: how do medical professionals and disability recipients characterize the severity of work limitations?

PURPOSE

Recent studies report systematic differences in how individuals categorize the severity of identical health and work limitation vignettes. We investigate how health professionals and disability recipients characterize the severity of work limitations and whether their reporting patterns are robust to demographic, education, and health characteristics. We use the results to illustrate the potential impact of reporting heterogeneity on the distribution of work disability estimated from self-reported categorical health and disability data.

METHOD

Nationally representative data on anchoring disability vignettes from the 2004 Health and Retirement Study (HRS) are used to investigate how respondents with an occupation background in health and Social Security disability beneficiaries categorize work limitation vignettes. Using pain, cardiovascular health, and depression vignettes, we estimate generalized ordered probit models (N = 2,660 individuals or 39,681 person-vignette observations) that allow the severity thresholds to vary by respondent characteristics.

RESULTS

We find that health professionals (excluding nurses) and disability recipients tend to classify identical work limitations as more severe compared to non-health professional non-disabled respondents. For disability recipients, the differences are most pronounced and particularly visible in the tails of the work limitations distribution. For health professionals, we observe smaller differences, affecting primarily the classification of mildly and moderately severe work limitations. The patterns for health professionals (excluding nurses) are robust to demographics, education, and health conditions. The greater likelihood of viewing the vignette person as more severely work limited observed among disability recipients is mostly explained by the fact that these respondents also tend to be in poorer health which itself predicts a more inclusive scale.

CONCLUSIONS

Knowledge of reporting scales from health professionals and disabled individuals can benefit researchers in a broad range of applications in health and disability research. They may be useful as reference scales to evaluate disability survey data. Such knowledge may be beneficial when studying disability programs. Given the increasing availability of anchoring vignette data in surveys, this is a promising area for future evaluation research.

p38γ MAPK is required for inflammation-associated colon tumorigenesis

Chronic inflammation has long been considered to causatively link to colon cancer development. However, signal transduction pathways involved remain largely unidentified. Here, we report that p38γ mitogen-activated protein kinase mediates inflammatory signaling to promote colon tumorigenesis. Inflammation activates p38γ in mouse colon tissues and intestinal epithelial cell-specific p38γ knockout (KO) attenuates colitis and inhibits pro-inflammatory cytokine expression. Significantly, p38γ KO inhibits tumorigenesis in a colitis-associated mouse model. The specific p38γ pharmacological inhibitor pirfenidone also suppresses pro-inflammatory cytokine expression and colon tumorigenesis. The tumor-promoting activity of epithelial p38γ was further demonstrated by xenograft studies. In addition, p38γ is required for β-catenin/Wnt activities and p38γ stimulates Wnt transcription by phosphorylating β-catenin at Ser605. These results show that p38γ activation links inflammation and colon tumorigenesis. Targeting p38γ may be a novel strategy for colon cancer prevention and treatment.

Sestrins function as guanine nucleotide dissociation inhibitors for Rag GTPases to control mTORC1 signaling

Mechanistic target of rapamycin complex 1 (mTORC1) integrates diverse environmental signals to control cellular growth and organismal homeostasis. In response to nutrients, Rag GTPases recruit mTORC1 to the lysosome to be activated, but how Rags are regulated remains incompletely understood. Here, we show that Sestrins bind to the heterodimeric RagA/B-RagC/D GTPases, and function as guanine nucleotide dissociation inhibitors (GDIs) for RagA/B. Sestrin overexpression inhibits amino-acid-induced Rag guanine nucleotide exchange and mTORC1 translocation to the lysosome. Mutation of the conserved GDI motif creates a dominant-negative form of Sestrin that renders mTORC1 activation insensitive to amino acid deprivation, whereas a cell-permeable peptide containing the GDI motif inhibits mTORC1 signaling. Mice deficient in all Sestrins exhibit reduced postnatal survival associated with defective mTORC1 inactivation in multiple organs during neonatal fasting. These findings reveal a nonredundant mechanism by which the Sestrin family of GDIs regulates the nutrient-sensing Rag GTPases to control mTORC1 signaling.

Sicker and Poorer: The Consequences of Being Uninsured for People With Disability During the Medicare Waiting Period

PURPOSE

Disabled individuals younger than 65 years are entitled to Medicare coverage through the Social Security Disability Insurance (DI) program, but only if they have completed a 2-year waiting period. This is the first study that uses longitudinal panel data, the Health and Retirement Study, and examines whether and to what extent the health and economic status are affected among disability beneficiaries who are uninsured during the Medicare waiting period.

METHODS

In a quasiexperiment research design, using a difference-in-difference (diff-in-diff) estimator, we compare changes in health and economic outcomes pre-/postentering the DI program for disability beneficiaries with alternative public health insurance and those without.

RESULTS

The adjusted diff-in-diff estimates suggest that disability beneficiaries who are uninsured during the waiting period, compared to those who are insured, are 13.6 percentage point more likely to report poor health, 6.3 percentage point less likely to be in excellent health, declare more difficulties in activities of daily living, and 30% higher medical expenditures from out of pocket.

CONCLUSIONS

The findings highlight punitive health and economic effects of the Medicare waiting period for uninsured disability beneficiaries. We also discuss the implications of the findings for the Affordable Care Act reform.

Electronic structures of in-plane two-dimensional transition-metal dichalcogenide heterostructures

In-plane two-dimensional MoS₂/WS₂ and MoSe₂/WS₂ heterostructures have been identified to show type-II band alignment and interface band bending.

Agarose particle-templated porous bacterial cellulose and its application in cartilage growth in vitro

Bacterial cellulose (BC) is a biocompatible hydrogel with a three-dimensional (3-D) structure formed by a dense network of cellulose nanofibers. A limitation of using BC for applications in tissue engineering is that the pore size of the material (∼0.02-10μm) is smaller than the dimensions of mammalian cells and prevents cells from penetrating into the material and growing into 3-D structures that mimic tissues. This paper describes a new route to porous bacterial cellulose (pBC) scaffolds by cultivating Acetobacter xylinum in the presence of agarose microparticles deposited on the surface of a growing BC pellicle. Monodisperse agarose microparticles with a diameter of 300-500μm were created using a microfluidic technique, layered on growing BC pellicles and incorporated into the polymer as A. xylinum cells moved upward through the growing pellicle. Removing the agarose microparticles by autoclaving produced BC gels containing a continuous, interconnected network of pores with diameters ranging from 300 to 500μm. Human P1 chondrocytes seeded on the scaffolds, replicated, invaded the 3-D porous network and distributed evenly throughout the substrate. Chondrocytes grown on pBC substrates displayed a higher viability compared to growth on the surface of unmodified BC substrates. The approach described in this paper introduces a new method for creating pBC substrates with user-defined control over the physical dimensions of the pore network, and demonstrates the application of these materials for tissue engineering.

Dynamic response of the scenic beauty value of different forests to various thinning intensities in central eastern China

Forest management has a significant influence on the preferences of people for forest landscapes. This study sought to evaluate the dynamic effects of thinning intensities on the landscape value of forests over time. Five typical stands in Wuxiangsi National Forest Park in Nanjing, China, were subjected to a thinning experiment designed with four intensities: unthinned, light thinning, moderate thinning, and heavy thinning. People's preferences for landscape photographs taken in plots under various thinning intensities were assessed through scenic beauty estimation (SBE) at 2 and 5 years after thinning. The differences in scenic beauty value between different thinning intensities were then analyzed with a paired samples t test for the two periods. The results indicated that the landscape value of all of the thinned plots significantly exceeded that of the unthinned plots 2 years after thinning (p < 0.01) and that the heavily thinned plots were most appreciated, showing an average improvement of 9.71 % compared with the control plots. Additionally, the heavily thinned plots were judged to be more beautiful than the lightly thinned and moderately thinned plots, whereas there was no significant difference between moderate thinning and light thinning. At 5 years after thinning, however, the moderately thinned plots received the highest preference scores among the four intensities, displaying an average improvement of 11.32 % compared with the unthinned plots. A multiple linear regression (MLR) model indicated that landscape value improved with increases in the average diameter at breast height (DBH) and with the improvement of environmental cleanliness in the stand, whereas the value decreased with an increasing stem density, species diversity, litter coverage, and canopy density. In addition, we found that the performance of a neural network model based on a multilayer perception (MLP) algorithm for predicting scenic beauty was slightly better than that of the MLR model. The findings of our study suggest that moderate to heavy thinning should be recommended to manage forests for the improvement of forest landscape value.

Classification and phagocytosis of circulating haemocytes in Chinese mitten crab (Eriocheir sinensis) and the effect of extrinsic stimulation on circulating haemocytes in vivo

Eriocheir sinensis (Henri Milne Edwards 1854) is one of the most important aquaculture species in China. In this investigation, we characterised the different types of haemocytes of E. sinensis using light and electron microscopy combined with cytochemical analysis and determined the in vivo phagocytic ability of different haemocyte types by injecting polystyrene beads. The haemocytes of E. sinensis were divided into three types: hyalinocytes, semigranulocytes and granulocytes. The hyalinocytes had no or few cytoplasmic granules; the semigranulocytes contained abundant small granules and a few large refractile cytoplasmic granules; and the granulocytes contained numerous large refractile cytoplasmic granules. The hyalinocytes were demonstrated to be the most abundant circulating haemocytes and the most avid phagocytic haemocytes, accounting for approximately 88.7% of the total phagocytes. The haemocyte-containing granules displayed limited phagocytic ability, with approximately 5.0% of granulocytes and 6.3% of semigranulocytes displaying positive phagocytic ability against the invading polystyrene beads in vivo. After injection with Aeromonas hydrophila, Bacillus subtilis and different concentrations of lipopolysaccharide for 0.25, 0.5, 1, 2, 4, 6 and 8 h, all three types of haemocytes experienced dramatic decline and then rapid recovery to their initial levels. A high concentration of lipopolysaccharide and A. hydrophila were extremely toxic to the crabs, as they induced a more serious loss of haemocytes compared with a low concentration of lipopolysaccharide and B. subtilis. Overall, the results obtained in this study indicate that a small proportion of the haemocytes of E. sinensis contributed to the phagocytic process, and the migration of haemocytes and haemocyte lysis were most likely a prominent pathway for pathogen elimination.

Mast cell-nerve cell interaction at acupoint: modeling mechanotransduction pathway induced by acupuncture

Mast cells are found abundant at sites of acupoints. Nerve cells share perivascular localization with mast cells. Acupuncture (mechanical stimuli) can activate mast cells to release adenosine triphosphate (ATP) which can activate nerve cells and modulates pain-processing pathways in response to acupuncture. In this paper, a mathematical model was constructed for describing intracellular Ca²⁺ signal and ATP release in a coupled mast cell and nerve cell system induced by mechanical stimuli. The results showed mechanical stimuli lead to a intracellular Ca²⁺ rise in the mast cell and ATP release, ATP diffuses in the extracellular space (ECS) and activates the nearby nerve cells, then induces electrical current in the nerve cell which spreads in the neural network. This study may facilitate our understanding of the mechanotransduction process induced by acupuncture and provide a methodology for quantitatively analyzing acupuncture treatment.

Bacterial cellulose as a substrate for microbial cell culture

Bacterial cellulose (BC) has a range of structural and physicochemical properties that make it a particularly useful material for the culture of bacteria. We studied the growth of 14 genera of bacteria on BC substrates produced by Acetobacter xylinum and compared the results to growth on the commercially available biopolymers agar, gellan, and xanthan. We demonstrate that BC produces rates of bacterial cell growth that typically exceed those on the commercial biopolymers and yields cultures with higher titers of cells at stationary phase. The morphology of the cells did not change during growth on BC. The rates of nutrient diffusion in BC being higher than those in other biopolymers is likely a primary factor that leads to higher growth rates. Collectively, our results suggest that the use of BC may open new avenues in microbiology by facilitating bacterial cell culture and isolation.

Construction, expression and immunogenicity of a novel anti-hypertension angiotensin II vaccine based on hepatitis A virus-like particle

Hypertension is a serious worldwide public health problem. The aim of this study is to design anti-hypertension angiotensin II (Ang II) vaccine using molecular biology and immunological method. This novel anti-hypertension vaccine, which is a chimeric protein named pHAV-4Ang IIs, presents four successive repeated Ang IIs as the functional epitope on the surface of the hepatitis A virus-like particle(HAVLP). In this study, pHAV-4Ang IIs was expressed using Bac-to-Bac Baculovirus Expression System. With the RT-PCR analysis, SDS-PAGE, western blot, IFA, electron microscope methods for identification of expression products, these results confirmed that stable expression of pHAV-4Ang IIs can be effectively achieved in infected sf9 cells. Spontaneous hypertensive rats (SHRs) were immunized with pHAV-4Ang IIs to test immunogenicity and pharmacodynamic action. The results showed that this anti-hypertension vaccine can induce high titer Ang II -specific IgG antibody for almost 10 weeks. When antibody titer reached the peak at 8th week, the mean systolic blood pressure (SBP) degraded approximately 23 mmHg compared with the PBS control group, and the mean diastolic blood pressure (DBP) degraded approximately 12 mmHg compared with the PBS control group. These results suggest that this anti-hypertension vaccine has good immunogenicity and good effect on reduction of blood pressure in SHRs, which provide reliable base for large-scale preparation of this hypertension vaccine in the future, and a new direction of exploration for the development of anti-hypertension therapeutic vaccine.

Uterine multiple leiomyomas complicated by extensive mucoid degeneration: case report

Uterine leiomyomas are the most common form of gynaecological tumours, and are exclusively benign. Only a few are associated with sarcomatous change. It is therefore important for the radiologist to be familiar with their range of appearances on magnetic resonance imaging (MRI) scans to distinguish them from other significant uterine pathologies, such as ovarian neoplasms, that require different management strategies. Here, the authors present the case of a 37-year-old Han woman, gravida 2, para 1 (cesarian section in 1996), who presented with a two-month history of lumbosacral swelling and pain. Physical examination revealed a pelvic mass and she was admitted with the presumptive diagnosis of an ovarian neoplasm. Laparotomy revealed multiple degenerated neoplasms that were benign in appearance, which was pathologically confirmed. A literature review was conducted to explore the natural history of uterine leiomyomas and their underlying etiopathogenesis. The optimal imaging modalities are also defined in the report, which enable the correct preoperative diagnosis to be made in order to optimize the care of women by multiple uterine leiomyomas.

RNA interference-mediated silencing of Stat5 induces apoptosis and growth suppression of hepatocellular carcinoma cells

It has been reported that Stat5 is overexpressed in a variety of human cancer cell lines and primary tumors. Inhibition of Stat5 in tumor cell lines has been associated with growth suppression and induction of apoptosis. However, no one of published studies have investigated the expression and role of Stat5 in hepatocellular carcinoma. In this study, we used human hepatocellular carcinoma cell line SMMC7721 as a model to demonstrate that Stat5 was highly expressed in these cells. Next we showed that RNAi mediated Stat5 knockdown could inhibit the proliferation and induce the apoptosis of SMMC7721 cells in vitro. Furthermore, we demonstrated that Stat5 knockdown inhibited the growth and induced the apoptosis of SMMC7721 cells in xenografts in nude mice. Taken together, our in vitro and in vivo data suggest that Stat5 plays an important role in human hepatocellular carcinoma. Inhibition of Stat5 by RNAi holds promise to be a novel gene therapy vector for hepatocellular carcinoma.

Nonmuscle myosin IIA is associated with poor prognosis of esophageal squamous cancer

Nonmuscle myosin IIA (myosin IIA) is a force-producing protein involved in the process of cell migration. Its expression has been considered as a bad prognostic indicator in stage I lung adenocarcinoma. However, the expression and clinical significance of myosin IIA in esophageal cancer has not been explored. In this study, we investigate the expression level of myosin IIA in 50 esophageal squamous cancer and 30 adjacent normal esophageal tissues by immunohistochemical staining and correlated its expression with clinicopathological features. Myosin IIA was expressed in all esophageal squamous cancer tissues (100%) and 8 of 30 adjacent normal tissues (26.7%, P = 0.000). In cancer tissues, elevated myosin IIA expression level was significantly correlated with increasing metastatic lymph nodes, poorer cancer differentiation, and advanced tumor stage. Further univariate analysis suggested that strong myosin IIA expression was associated with a significantly shorter overall survival (P = 0.021). In addition, MYH9 SiRNA was transfected into esophageal squamous cancer cell line (KYSE-510) to study the role of myosin IIA in cell migration. SiRNA-mediated depletion of myosin IIA in KYSE-510 cells significantly increased cell-matrix adhesion and attenuated cell migration ability (P = 0.000). In conclusion, these findings indicate that overexpression of myosin IIA may contribute to the progression and poor prognosis of esophageal squamous cancer, and this effect may be associated with increased cancer cell migration.

Functional specialization of islet dendritic cell subsets

Dendritic cells (DC) play important roles in both tolerance and immunity to β cells in type 1 diabetes. How and why DC can have diverse and opposing functions in islets remains elusive. To answer these questions, islet DC subsets and their specialized functions were characterized. Under both homeostatic and inflammatory conditions, there were two main tissue-resident DC subsets in islets, defined as CD11b(lo/-)CD103(+)CX3CR1(-) (CD103(+) DC), the majority of which were derived from fms-like tyrosine kinase 3-dependent pre-DC, and CD11b(+)CD103(-)CX3CR1(+) (CD11b(+) DC), the majority of which were derived from monocytes. CD103(+) DC were the major migratory DC and cross-presented islet-derived Ag in the pancreatic draining lymph node, although this DC subset displayed limited phagocytic activity. CD11b(+) DC were numerically the predominant subset (60-80%) but poorly migrated to the draining lymph node. Although CD11b(+) DC had greater phagocytic activity, they poorly presented Ag to T cells. CD11b(+) DC increased in numbers and percentage during T cell-mediated insulitis, suggesting that this subset might be involved in the pathogenesis of diabetes. These data elucidate the phenotype and function of homeostatic and inflammatory islet DC, suggesting differential roles in islet immunity.

Tolerance and lymphoid organ structure and function

This issue of Frontiers in Immunologic Tolerance explores barriers to tolerance from a variety of views of cells, molecules, and processes of the immune system. Our laboratory has spent over a decade focused on the migration of the cells of the immune system, and dissecting the signals that determine how and where effector and suppressive regulatory T cells traffic from one site to another in order to reject or protect allografts. These studies have led us to a greater appreciation of the anatomic structure of the immune system, and the realization that the path taken by lymphocytes during the course of the immune response to implanted organs determines the final outcome. In particular, the structures, microanatomic domains, and the cells and molecules that lymphocytes encounter during their transit through blood, tissues, lymphatics, and secondary lymphoid organs are powerful determinants for whether tolerance is achieved. Thus, the understanding of complex cellular and molecular processes of tolerance will not come from “96-well plate immunology,” but from an integrated understanding of the temporal and spatial changes that occur during the response to the allograft. The study of the precise positioning and movement of cells in lymphoid organs has been difficult since it is hard to visualize cells within their three-dimensional setting; instead techniques have tended to be dominated by two-dimensional renderings, although advanced confocal and two-photon systems are changing this view. It is difficult to precisely modify key molecules and events in lymphoid organs, so that existing knockouts, transgenics, inhibitors, and activators have global and pleiotropic effects, rather than precise anatomically restricted influences. Lastly, there are no well-defined postal codes or tracking systems for leukocytes, so that while we can usually track cells from point A to point B, it is exponentially more difficult or even impossible to track them to point C and beyond. We believe this represents one of the fundamental barriers to understanding the immune system and devising therapeutic approaches that take into account anatomy and structure as major controlling principles of tolerance.

Lymphangiogenesis is required for pancreatic islet inflammation and diabetes

Lymphangiogenesis is a common phenomenon observed during inflammation and engraftment of transplants, but its precise role in the immune response and underlying mechanisms of regulation remain poorly defined. Here we showed that in response to injury and autoimmunity, lymphangiogenesis occurred around islets and played a key role in the islet inflammation in mice. Vascular endothelial growth factors receptor 3 (VEGFR3) is specifically involved in lymphangiogenesis, and blockade of VEGFR3 potently inhibited lymphangiogenesis in both islets and the draining LN during multiple low-dose streptozotocin (MLDS) induced autoimmune insulitis, which resulted in less T cell infiltration, preservation of islets and prevention of the onset of diabetes. In addition to their well-known conduit function, lymphatic endothelial cells (LEC) also produced chemokines in response to inflammation. These LEC attracted two distinct CX3CR1^hi and LYVE-1⁺ macrophage subsets to the inflamed islets and CX3CR1^hi cells were influenced by LEC to differentiate into LYVE-1⁺ cells closely associated with lymphatic vessels. These observations indicate a linkage among lymphangiogenesis and myeloid cell inflammation during insulitis. Thus, inhibition of lymphangiogenesis holds potential for treating insulitis and autoimmune diabetes.

Clinicopathological significance of Rb and E2F1 expression in esophageal squamous cell carcinoma

AIM: To investigate the expression of Rb and E2F1 in esophageal squamous cell carcinoma (ESCC) and to analyze their clinicopathological significance.

METHODS: Forty-eight ESCC specimens were taken from Xinjiang Kazaks patients and used in the study. Matched normal esophageal mucosal tissues were used as controls. The expression of Rb and E2F1 was detected by RT-PCR. The correlation of Rb and E2F1 expression with the development and progression of ESCC was then analyzed.

RESULTS: The positive rate of Rb expression was higher in ESCC than in normal esophageal mucosal tissue (64.6% vs 43.8%, P < 0.05). E2F1 expression in ESCC showed no significant difference with that in normal esophageal mucosal tissue (70.8% vs 75%, P > 0.05). Rb and E2F1 expression showed no significant correlation with tumor differentiation and stage (both P > 0.05). Rb expression was positively correlated with that of E2F1 in ESCC (r = 0.867, P < 0.05).

CONCLUSION: High expression of Rb may be involved in the development and progression of ESCC.

Modified Thoracoscopic versus Minimally Invasive Oesophagectomy in Curative Resection of Oesophageal Cancer

Conventional thoracoscopic oesophagectomy is time-consuming and requires sophisticated endoscopic skills. To reduce these problems we have modified the operating procedure, first by anastomosis of the oesophagus with the tubular stomach pulled up via the retrosternal route, followed by thoracoscopic oesophagectomy (modified thoracoscopic oesophagectomy). Outcomes were compared between the modified procedure and minimally invasive oesophagectomy. There were no significant differences in general preoperative clinical characteristics between the two patient groups. The modified thoracoscopic oesophagectomy group had significantly lower hospitalization expenses, significantly shorter operation times and significantly more lymph nodes removed compared with the minimally invasive oesophagectomy group, but there were no significant group differences in lengths of hospital and intensive care unit stays, morbidity and mortality. These results indicate that modified thoracoscopic oesophagectomy is feasible, simplifies operating procedures and reduces hospitalization expenses with acceptable morbidity.

Stat4 is critical for the balance between Th17 cells and regulatory T cells in colitis

Th17 play a central role in autoimmune inflammatory responses. Th1 are also necessary for autoimmune disease development. The interplay of Th1 signals and how they coordinate with Th17 during inflammatory disease pathogenesis are incompletely understood. In this study, by adding Stat4 deficiency to Stat6/T-bet double knockout, we further dissected the role of Stat4 in Th1 development and colitis induction. We showed that in the absence of the strong Th2 mediator Stat6, neither Stat4 nor T-bet is required for IFN-γ production and Th1 development. However, addition of Stat4 deficiency abolished colitis induced by Stat6/T-bet double-knockout cells, despite Th1 and Th17 responses. The failure of colitis induction by Stat4/Stat6/T-bet triple-knockout cells is largely due to elevated Foxp3(+) regulatory T cell (Treg) development. These results highlight the critical role of Stat4 Th1 signals in autoimmune responses in suppressing Foxp3(+) Treg responses and altering the balance between Th17 and Tregs to favor autoimmune disease.

[Selective screening of inborn errors of metabolism by using the tandem mass spectrometry: pilot study of 552 children at high risk]

OBJECTIVE

To study the application of tandem mass spectrometry (MS/MS) in the selective screening of inborn errors of metabolism (IEM) in high risk children and to understand the positive rate and types of IEM.

METHODS

MS/MS was used to examine 552 blood samples from high risk cases of IEM who came from 8 hospitals in Shijiazhuang, Hebei Province.

RESULTS

Sixty-four children (11.6%) were confirmed with IEM by the MS/MS, including 33 cases of methylmalonic acidemia or propionic acidemias, 2 cases of phenylketonuria, 3 cases of carnitine palmotoyl transferase I deficiency, 1 case of long-chain acyl-CoA dehydrogenase deficiency, 2 cases of medium-chain acyl-CoA dehydrogenase deficiency, 6 cases of maple syrup urine disease, 2 cases of short-chain acyl-CoA dehydrogenase deficiency, 2 cases of glutaric acidemia type I, 2 cases of isovaleric acidemia, 2 cases of homocystinuria, 4 cases of carnitine deficiency, 1 case of tyrosinemia, 1 case of argininosuccinic aciduria, 2 cases of citrullinemia and 1 case of argininemia.

CONCLUSIONS

MS/MS can be used to screen and classify IEM.

Distinct inflammatory signals have physiologically divergent effects on epigenetic regulation of Foxp3 expression and Treg function

Foxp3 expression in regulatory T cells (Treg) is required for their development and suppressive function. How different inflammatory signals affect Foxp3 chromatin structure, expression and Tregs plasticity are not completely known. In the present study, the Toll-like receptor 2 (TLR2) ligand peptidoglycan inhibited Foxp3 expression in both natural Treg (nTreg) and TGFβ-driven adaptive Treg (aTreg). Inhibition was independent of paracrine Th1, Th2 and Th17 cytokines. PGN-induced T cell-intrinsic TLR2-Myd88-dependent IFR1 expression and induced IRF1 bound to IRF1 response elements (IRF-E) in the Foxp3 promoter and intronic enhancers, and negatively regulated Foxp3 expression. Inflammatory IL-6 and TLR2 signals induced divergent chromatin changes at the Foxp3 locus and regulated Treg suppressor function, and in an islet transplant model resulted in differences in their ability to prolong graft survival. These findings are important for understanding how different inflammatory signals can affect the transplantation tolerance and immunity.