iTRAQ-based proteomics identifies proteins associated with betaine accumulation in Lycium barbarum L.

In order to better understand the mechanism of betaine accumulation in Lycium barbarum L. (LBL), we used iTRAQ (Isotope relative and absolute quantitative labeling) proteomics to screen and identify differentially abundant proteins (DAPs) at five stages (S1-young fruit stage, S2-green fruit stage, S3-early yellowing stage, S4-late yellowing stage, S5-ripening stage). A total of 1799 DAPs and 171 betaine-related DAPs were identified, and phosphatidylethanolamine N-methyltransferase (NMT), choline monooxygenase (CMO), and betaine aldehyde dehydrogenase (BADH) were found to be the key enzymes related to betaine metabolism. These proteins are mainly involved in carbohydrates, amino acids and their derivatives, fatty acids, carboxylic acids, photosynthesis and photoprotection, isoquinoline alkaloid biosynthesis, peroxisomes, and glycine, serine, and threonine metabolism. Three of the key enzymes were also up- and down-regulated to different degrees at the mRNA level. The study provide new insights into the of mechanism of betaine accumulation in LBL. SIGNIFICANCE: Betaine, a class of naturally occurring, water-soluble alkaloids, has been found to be widespread in animals, higher plants, and microbes. In addition to being an osmotic agent, betaine has biological functions such as hepatoprotection, neuroprotection, and antioxidant activity. Betaine metabolism (synthesis and catabolism) is complexly regulated by developmental and environmental signals throughout the life cycle of plant fruit maturation. As a betaine-accumulating plant, little has been reported about the regulatory mechanisms of betaine metabolism during the growth and development of Lycium barbarum L. (LBL) fruit. Therefore, this study used iTRAQ quantitative proteomics technology to investigate the abundance changes of betaine-related proteins in LBL fruit, screen and analyze the differential abundance proteins related to betaine metabolism, and provide theoretical references for the in-depth study of the mechanism of betaine metabolism in LBL fruit.

Proteomic and metabolomic analysis of ageing beef exudate to determine that iron metabolism enhances muscle protein and lipid oxidation.

The study aimed to assess differences in proteomic and metabolite profiles in ageing (1, 2, 4, and 6 days at 4 °C) beef exudates and determine their relationship with beef muscle iron metabolism and oxidation. Proteomic and metabolomic analyses identified 877 metabolites and 1957 proteins. The joint analysis identified 24 differential metabolites (DMs) and 56 differentially expressed proteins (DEPs) involved in 15 shared pathways. Ferroptosis was identified as the only iron metabolic pathway, and 4 DMs (l-glutamic acid, arachidonic acid, glutathione and gamma-glutamylcysteine) and 5 DEPs (ferritin, phospholipid hydroperoxide glutathione peroxidase, heme oxygenase 1, major prion protein, and acyl-CoA synthetase long chain family member 4) were involved in iron metabolism by regulating heme and ferritin degradation, Fe2+ and Fe3+ conversion, arachidonic acid oxidation and inactivation of glutathione peroxidase (GPX) 4, leading to increased levels of free iron, ROS, protein and lipid oxidation (P < 0.05). Overall, abnormal iron metabolism during ageing induced oxidative stress in muscle tissue.

MZB1-mediated IgA secretion suppresses the development and progression of colorectal cancer triggered by gut inflammation.

Colorectal cancer (CRC) ranks among the top causes of mortality globally. Gut inflammation is one crucial risk factor that augments CRC development since patients suffering from inflammatory bowel disease have an increased incidence of CRC. The role of immunoglobulin (Ig)A in maintaining gut homeostasis and preventing inflammation has been well established. Our earlier work demonstrated that the marginal zone and B1 cell-specific protein (MZB1) promotes gut IgA secretion and its absence results in pronounced dextran sulfate sodium salt (DSS)-induced colitis. In the present study, we explored the role of MZB1 in CRC development using the azoxymethane (AOM)/DSS-induced CRC model. We observed an increase in both the number and size of the tumor nodules in Mzb1-/- mice compared with Mzb1+/+ mice. The increase in CRC development and progression in Mzb1-/- mice was associated with reduced intestinal IgA levels, altered gut flora, and more severe gut and systemic inflammation. Oral administration of the monoclonal IgA, W27, alleviated both the gut inflammation and AOM/DSS-induced CRC. Notably, cohousing Mzb1+/+ and Mzb1-/- mice from the 10th day after birth led to similar CRC development. Our findings underscore the pivotal role of MZB1-mediated IgA secretion in suppressing the onset and progression of CRC triggered by gut inflammation. Moreover, our study highlights the profound impact of microbiota composition, modulated by gut IgA levels, on gut inflammation. Nonetheless, establishing a direct correlation between the severity of colitis and subsequent CRC development and the presence or absence of a particular microbiota is challenging.

Biomimetic pheomelanin to unravel the electronic, molecular and supramolecular structure of the natural product.

Herein, we investigate synthetic routes to a close mimic of natural pheomelanin. Three different oxidative polymerization routes were attempted to generate synthetic pheomelanin, each giving rise to structurally dissimilar materials. Among them, the route employing 5-cysteinyl-dihydroxyphenylalanine (5-CD) as a monomer was verified as a close analogue of extracted pheomelanin from humans and birds. The resulting biomimetic and natural pheomelanins were compared via various techniques, including solid-state Nuclear Magnetic Resonance (ssNMR) and Electron Paramagnetic Resonance (EPR). This synthetic pheomelanin closely mimics the structure of natural pheomelanin as determined by parallel characterization of pheomelanin extracted from multiple biological sources. With a good synthetic biomimetic material in hand, we describe cation-π interactions as an important driving force for pheomelanogenesis, further advancing our fundamental understanding of this important biological pigment.

Ferritin-dependent cellular autophagy pathway promotes ferroptosis in beef during cold storage.

Ferroptosis plays a pivotal role in regulating various physiological processes and quality of post-mortem muscle. However, the molecular mechanisms underlying ferroptosis remain unclear. The study investigated how ferroptosis was induced in beef during cold storage. Results showed that the expression of autophagy-related genes, LC3, ATG5, ATG7, and NCOA4 in beef during cold storage promoted the degradation of ferritin heavy chains. Ferritin evoked ferroptosis by releasing free iron, inducing reactive oxygen species (ROS) accumulation and inhibiting the glutathione (GSH)-glutathione peroxidase 4 (GPX4) pathway. Furthermore, treatment of myoblasts with GSK 2656157 (autophagy inhibitor) showed that ferritin degradation was lower in the GSK 2656157-treated myoblasts than in the control, while GSH content and GPX4 activity were higher than the control (P < 0.05), and the contents of free iron, ROS and malondialdehyde, and apoptosis were lower than the control (P < 0.05). These results suggest that ferroptosis is induced by degradation of ferritin via the autophagic pathway.

Glutathione metabolism-mediated ferroptosis reduces water-holding capacity in beef during cold storage.

To investigate the potential mechanisms by which cold storage affects the water-holding capacity (WHC) of beef through analysis of exudates using an untargeted metabolomics strategy. A total of 877 metabolites were detected in four groups of beef exudates that have been frozen for 1, 2, 4, and 6 days, of which, 278 were identified as differential metabolites (DMs). The metabolic pathways of the DMs analysed by KEGG pathway enrichment included ABC transporters, purine metabolism, biosynthesis of cofactors, protein digestion and absorption, and ferroptosis. Ferroptosis was identified during storage of beef, and the reduction in WHC of beef was accompanied by a ferroptosis process. In addition, six DMs were identified in the KEGG pathway of ferroptosis, and the process of cellular ferroptosis was dependent on the inhibition of glutathione metabolic processes. Overall, the ferroptosis of cells during beef storage had a negative impact on WHC, and the finding of ferroptosis complemented the post-slaughter apoptosis.

[Analysis of CHD7 gene variants in 22 patients with idiopathic hypogonadotropic hypogonadism].

OBJECTIVE: To explore clinical evaluation and genetic analysis of patients with idiopathic hypogonadotropic hypogonadism (IHH). METHODS: The clinical data and phenotypes of 22 patients with IHH diagnosed and treated in our department were reviewed and analyzed. Whole-exome sequencing (WES) and Sanger method were used for variant analysis and verification. RESULTS: Among the 22 cases of IHH probands, 12 cases of Kalman syndrome (KS) and 10 cases of IHH (nIHH) with normal sense of smell. On physical examination, males showed short penis, small testicles, small or inconspicuous laryngeal knots, and a sharp voice. Mammary gland development, mammary gland dysplasia, primary amenorrhea, etc. in women. Sex hormone examination: Follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), estradiol (E2) levels are reduced or at the lower limit of normal. There were nine missense variants of CHD7 gene in 8 patients. Based on the American College of Medical Genetics and Genomics guidelines, the c.307T>A(p.Ser103Thr), c.3143G>A(p.Gly1048Glu), c.6956G>T (p.Arg2319Leu) and c.3145A>T (p.Ser1049Cys) variants of CHD7 gene were predicted to be likely pathogenic (PS1+PP1+PM2, PM2+PM6+PP2+PP3, PM2+PM5+PM6+PP2+PP3 and PM2+PM6+PP2+PP3), the remaining 14 cases of IHH patients had negative genetic screening. CONCLUSION: CHD7 gene variants may be related to IHH disease.

Light-Powered Ion Pumping in a Cation-Selective Conducting Polymer Membrane.

The simulation of the ion pumping against a proton gradient energized by light in photosynthesis is of significant importance for the energy conversion in a non-biological environment. Herein, we report light-powered ion pumping in a polystyrene sulfonate anion (PSS) doped polypyrrole (PPy) conducting polymer membrane (PSS-PPy) with a symmetric geometry. This PSS-PPy conducting polymer membrane exhibits a cationic selectivity and a light-responsive surface-charge-governed ion transport attributed to the negatively charged PSS groups. An asymmetric visible irradiation on one side of the PSS-PPy membrane induces a built-in electric field across the membrane due to the intrinsic photoelectronic property of PPy, which drives the cationic transport against the concentration gradient, demonstrating an ion-pumping effect. This work is a prototype that uses a geometry-symmetric conducting polymer membrane as a light-powered artificial ion pump for active ion transport, which exhibits potential applications in nanofluidic energy conversion.

Intramuscular Near-Infrared Spectroscopy for Muscle Flap Monitoring in a Porcine Model.

BACKGROUND: Current near-infrared spectroscopy (NIRS)-based systems for continuous flap monitoring are limited to flaps which carry a cutaneous paddle. As such, this useful and reliable technology has not previously been applicable to muscle-only free flaps where other modalities with substantial limitations continue to be utilized. METHODS: We present the first NIRS probe which allows continuous monitoring of local tissue oxygen saturation (StO2) directly within the substance of muscle tissue. This probe is flexible, subcentimeter in scale, waterproof, biocompatible, and is fitted with resorbable barbs which facilitate temporary autostabilization followed by easy atraumatic removal. This novel device was compared with a ViOptix T.Ox monitor in a porcine rectus abdominus myocutaneous flap model of arterial and venous occlusions. During these experiments, the T.Ox device was affixed to the skin paddle, while the novel probe was within the muscle component of the same flap. RESULTS: The intramuscular NIRS device and skin-mounted ViOptix T.Ox devices produced very similar StO2 tracings throughout the vascular clamping events, with obvious and parallel changes occurring upon vascular clamping and release. The normalized cross-correlation at zero lag describing correspondence between the novel intramuscular NIRS and T.Ox devices was >0.99. CONCLUSION: This novel intramuscular NIRS probe offers continuous monitoring of oxygen saturation within muscle flaps. This experiment demonstrates the potential suitability of this intramuscular NIRS probe for the task of muscle-only free flap monitoring, where NIRS has not previously been applicable. Testing in the clinical environment is necessary to assess durability and reliability.

Discovery and engineering of small SlugCas9 with broad targeting range and high specificity and activity.

The compact CRISPR/Cas9 system, which can be delivered with their gRNA and a full-length promoter for expression by a single adeno-associated virus (AAV), is a promising platform for therapeutic applications. We previously identified a compact SauriCas9 that displays high activity and requires a simple NNGG PAM, but the specificity is moderate. Here, we identified three compact Cas9 orthologs, Staphylococcus lugdunensis Cas9 (SlugCas9), Staphylococcus lutrae Cas9 (SlutrCas9) and Staphylococcus haemolyticus Cas9 (ShaCas9), for mammalian genome editing. Of these three Cas9 orthologs, SlugCas9 recognizes a simple NNGG PAM and displays comparable activity to SaCas9. Importantly, we generated a SlugCas9-SaCas9 chimeric nuclease, which has both high specificity and high activity. We finally engineered SlugCas9 with mutations to generate a high-fidelity variant that maintains high specificity without compromising on-target editing efficiency. Our study offers important minimal Cas9 tools that are ideal for both basic research and clinical applications.

Proapoptotic Peptide Brush Polymer Nanoparticles via Photoinitiated Polymerization-Induced Self-Assembly.

Herein, we report the photoinitiated polymerization-induced self-assembly (photo-PISA) of spherical micelles consisting of proapoptotic peptide-polymer amphiphiles. The one-pot synthetic approach yielded micellar nanoparticles at high concentrations and at scale (150 mg mL-1 ) with tunable peptide loadings up to 48 wt. %. The size of the micellar nanoparticles was tuned by varying the lengths of hydrophobic and hydrophilic building blocks. Critically, the peptide-functionalized nanoparticles imbued the proapoptotic "KLA" peptides (amino acid sequence: KLAKLAKKLAKLAK) with two key properties otherwise not inherent to the sequence: 1) proteolytic resistance compared to the oligopeptide alone; 2) significantly enhanced cell uptake by multivalent display of KLA peptide brushes. The result was demonstrated improved apoptosis efficiency in HeLa cells. These results highlight the potential of photo-PISA in the large-scale synthesis of functional, proteolytically resistant peptide-polymer conjugates for intracellular delivery.

A compact Cas9 ortholog from Staphylococcus Auricularis (SauriCas9) expands the DNA targeting scope.

Compact CRISPR/Cas9 systems that can be packaged into an adeno-associated virus (AAV) hold great promise for gene therapy. Unfortunately, currently available small Cas9 nucleases either display low activity or require a long protospacer adjacent motif (PAM) sequence, limiting their extensive applications. Here, we screened a panel of Cas9 nucleases and identified a small Cas9 ortholog from Staphylococcus auricularis (SauriCas9), which recognizes a simple NNGG PAM, displays high activity for genome editing, and is compact enough to be packaged into an AAV for genome editing. Moreover, the conversion of adenine and cytosine bases can be achieved by fusing SauriCas9 to the cytidine and adenine deaminase. Therefore, SauriCas9 holds great potential for both basic research and clinical applications.

Mechanism of UVA Degradation of Synthetic Eumelanin.

Eumelanin is a ubiquitous natural pigment that has a broad absorption across ultraviolet (UV, 100-400 nm) and visible wavelengths (400-700 nm) and can protect against radiation. Synthetic eumelanin with properties similar to natural eumelanin has been made using dopamine or dihydroxyindole. Here, we use solid-state nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy to elucidate the chemical structure of synthetic eumelanins (made from dopamine and l-3,4-dihydroxyphenylalanine precursors) and investigate how their structures change after intensive UVA (315-400 nm) exposure. We first confirm that polydopamine has indole units. Upon UV exposure, the pyrrole ring in this indole unit remains intact, and a fraction of the six-membered benzyl ring is broken and the indole potentially converted to furo[3,4-b]pyrrole. This change in the chemical structure is accompanied by a release of carbon dioxide. In addition, the sepia (natural) eumelanin used for comparison is more stable than the synthetic eumelanin. Understanding the UVA degradation mechanism of eumelanin will help reveal the role of eumelanin in skin cancer and in the design of more efficient UV stabilizers.

Concentrated Ambient PM2.5-Induced Inflammation and Endothelial Dysfunction in a Murine Model of Neural IKK2 Deficiency.

BACKGROUND: Exposure to ambient fine particulate matter (PM2.5) is associated with cardiovascular mortality, but underlying pathophysiologic mechanisms are not fully understood. Hypothalamic inflammation, characterized by the activation of Inhibitor kappaB kinase 2/Nuclear factor kappaB (IKK2/NF-κB) signaling pathway, may play an important role in the pathogenesis of cardiovascular diseases. We recently demonstrated that hypothalamic inflammation is increased in mice exposed to concentrated ambient PM2.5 (CAP). OBJECTIVES: In the present study, we used a neuron-specific IKK2 knockout mouse model to examine the role of neural IKK2 expression and hypothalamic inflammation in the pathophysiologic effects of PM2.5. METHODS: We assessed inflammatory and vascular responses in Nestin-creIKK2flox/flox (IKK2Neu-KO) and littermate Nestin-creIKK2flox/+ (control) mice after 4 mo of exposure to filtered air (FA) or CAP. RESULTS: CAP exposure was associated with significantly higher tumor necrosis factor-α (TNFα) and interleukin (IL)-6 mRNA in the hypothalamus of control mice, but not IKK2Neu-KO mice. In addition, CAP exposure-induced increases in bronchoalveolar lavage fluid (BALF) leukocytes, pulmonary macrophage infiltration and IL-6 expression, plasma TNFα and IL-1ß levels, adipose macrophage infiltration and IL-1ß expression, and endothelial dysfunction were reduced or absent in IKK2Neu-KO mice compared with controls. CONCLUSIONS: Our findings support a role of neural IKK2 in CAP exposure-induced local and systemic pro-inflammatory cytokine expression, pulmonary and adipose inflammation, and endothelial dysfunction, thus providing insight into pathophysiologic mechanisms that may mediate effects of PM2.5 exposure. https://doi.org/10.1289/EHP2311.

From the Cover: Lung-Specific Overexpression of Constitutively Active IKK2 Induces Pulmonary and Systemic Inflammations but Not Hypothalamic Inflammation and Glucose Intolerance.

The lung is constantly exposed to ambient pollutants such as ambient fine particulate matter (PM2.5), making it one of the most frequent locations of inflammation in the body. Given the establishment of crucial role of inflammation in the pathogenesis of cardiometabolic diseases, pulmonary inflammation is thus widely believed to be an important risk factor for cardiometabolic diseases. However, the causality between them has not yet been well established. To determine if pulmonary inflammation is sufficient to cause adverse cardiometabolic effects, SFTPC-rtTA+/-tetO-cre+/-pROSA-inhibitor κB kinase 2(IKK2)ca+/- (LungIKK2ca) and littermate SFTPC-rtTA+/-tetO-cre-/-pROSA-IKK2ca+/- wildtype (WT) mice were fed with doxycycline diet to induce constitutively active Ikk2 (Ikk2ca) overexpression in the lung and their pulmonary, systemic, adipose, and hypothalamic inflammations, vascular function, and glucose homeostasis were assessed. Feeding with doxycycline diet resulted in IKK2ca overexpression in the lungs of LungIKK2ca but not WT mice. This induction of IKK2ca was accompanied by marked pulmonary inflammation as evidenced by significant increases in bronchoalveolar lavage fluid leukocytes, pulmonary macrophage infiltration, and pulmonary mRNA expression of tumor necrosis factor α (Tnfα) and interleukin-6 (Il-6). This pulmonary inflammation due to lung-specific overexpression of IKK2ca was sufficient to increase circulating TNFα and IL-6 levels, adipose expression of Tnfα and Il-6 mRNA, aortic endothelial dysfunction, and systemic insulin resistance. Unexpectedly, no significant alteration in hypothalamic expression of Tnfα and Il-6 mRNA and glucose intolerance were observed in these mice. Pulmonary inflammation is sufficient to induce systemic inflammation, endothelial dysfunction, and insulin resistance, but not hypothalamic inflammation and glucose intolerance.

Inactivation of TNF/LT locus alters mouse metabolic response to concentrated ambient PM2.5.

BACKGROUND: Exposure to ambient fine particulate matter (PM2.5) is associated with increased cardiometabolic morbidity and mortality. This is widely believed to be attributable to PM2.5 exposure-induced pulmonary and subsequent systemic inflammation. Tumor necrosis factor alpha (TNFα), lymphotoxin α (LTα), and lymphotoxin ß (LTß) are three homologous pro-inflammatory cytokines, each with both unique and redundant activities in inflammation. Their role in PM2.5 exposure-induced inflammation and adverse cardiometabolic effects has to be determined. METHODS AND RESULTS: LTα/TNFα/LTß triple-knockout (TNF/LT KO) and wildtype (WT) mice were exposed to concentrated ambient PM2.5 (CAP) for 5 months. Lung pathological analysis revealed that TNF/LT deficiency reduced CAP exposure-induced pulmonary inflammation. However, glucose homeostasis assessments showed that TNF/LT deficiency significantly aggravated CAP exposure-induced glucose intolerance and insulin resistance. Consistent with glucose homeostasis assessments, CAP exposure significantly increased the body weight and adiposity of TNF/LT KO but not WT mice. In contrast to its body weight effects, CAP exposure reduced food intake of WT but not TNF/LT KO mice. On the other hand, CAP exposure induced marked fat droplet accumulation in brown adipose tissues of WT mice and significantly decreased their uncoupling protein 1 (UCP1) expression, and these effects were markedly exacerbated in TNF/LT KO mice. CONCLUSION: The present study suggests that TNF/LT deficiency influences PM2.5 exposure-induced response of energy metabolism through alterations in both food intake and energy expenditure.

Mimicking Melanosomes: Polydopamine Nanoparticles as Artificial Microparasols.

A primary role of melanin in skin is the prevention of UV-induced nuclear DNA damage to human skin cells, where it serves to screen out harmful UV radiation. Melanin is delivered to keratinocytes in the skin after being excreted as melanosomes from melanocytes. Defects in melanin production in humans can cause diseases, many of which currently lack effective treatments due to their genetic origins (e.g., skin cancer, vitiligo, and albinism). The widespread prevalence of melanin-related diseases and an increasing interest in the performance of various polymeric materials related to melanin necessitates novel synthetic routes for preparing melanin-like materials. In this work, we prepared melanin-like nanoparticles (MelNPs) via spontaneous oxidation of dopamine, as biocompatible, synthetic analogues of naturally occurring melanosomes, and investigated their uptake, transport, distribution, and UV-protective capabilities in human keratinocytes. Critically, we demonstrate that MelNPs are endocytosed, undergo perinuclear aggregation, and form a supranuclear cap, or so-called microparasol in human epidermal keratinocytes (HEKa), mimicking the behavior of natural melananosomes in terms of cellular distribution and the fact that they serve to protect the cells from UV damage.

[A preliminary study of the significance of autoantibodies against light chain of myeloperoxidase on pulmonary damages in myeloperoxidase-antineutrophil cytoplasmic antibody associated vasculitis].

OBJECTIVE: To investigate the clinical characteristics of myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (MPO-AAV) with pulmonary injury and the relationship between pulmonary injury and ANCA against light chain of MPO (LCMPO-ANCA). METHODS: A total of 195 patients with newly diagnosed primary active MPO-AAV were recruited in this prospective study. Indirect immunofluorescence assay was used to detect peri-nuclear ANCA (p-ANCA). Immunoblotting and ELISA were used to detect myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA). Clinical features of patients with both positive p-ANCA and MPO-ANCA were collected. Disease activity was evaluated by Birmingham Vasculitis Activity Score- version 3 (BVAS-V3) Recombinant light chain of MPO was used to coat substrate of LCMPO-ANCA by ELISA. The clinical characteristics of pulmonary injury and its correlation with serum levels of p-ANCA, MPO-ANCA and LCMPO-ANCA were explored. RESULTS: All 195 patients (64 male and 131 female), consisted of 191 patients (98.0%) with microscopic polyangiitis, 3 patients (1.5%) with granulomatosis with polyangiitis, and 1(0.5%) with eosinophilic granulomatosis with polyangiitis including 64 men and 131 women. Their mean age was (63.2 ± 13.5) years old. The level of MPO-ANCA had a positive correlation with general BVAS-V3 (r=0.193, P=0.007) in all patients, and the level of LCMPO-ANCA was positively related with the pulmonary BVAS-V3 (r=0.228, P=0.001). As for multiple systemic damages, the incidence of lung involvement was 60.51% (118/195), which ranked second to renal involvement (71.80%, 140/195). The most common pulmonary injuries represented as pulmonary infiltration of 80.51% (95/118), pleural effusion / pleurisy of 41.53% (49/118), pulmonary nodule or cavity of 22.03% (26/118). Compared with those without lung involvement, the patients with pulmonary injuries were older [(66.39 ± 10.70) years old vs (58.30 ± 15.72) years old; t=4.277, P=0.001], had a shorter course of disease [2.00(1.00,10.50) months vs 3.00(1.00,3.50) months; t=-2.283, P=0.024], and higher scores of general BVAS-V3 (18.21 ± 6.08 vs 15.18 ± 5.64; t=3.501, P=0.001). Also, in the patients with pulmonary lesions, the positive rate of LCMPO-ANCA was significantly higher (35.59% vs 6.49%; χ² =21.569, P<0.001), and the level of LCMPO-ANCA was significantly higher (0.377 ± 0.229 vs 0.285 ± 0.079; t=3.399, P=0.001) than those without lung involvement. The pulmonary BVAS-V3 in the patients with LCMPO-ANCA was significantly higher than that in the patients without LCMPO-ANCA (4.34 ± 2.10 vs 2.59 ± 2.52; t=4.301, P<0.001), whereas the pulmonary BVAS-V3 was not correlated with LCMPO-ANCA (r=0.035, P=0.708) in patients with lung injuries. CONCLUSION: Pulmonary injury was relatively common and insidious in patients with MPO-AAV. To monitor ANCA level is necessary in patients with pulmonary injury. LCMPO-ANCA might play an important role in the pathogenesis of pulmonary lesions in AAV.

PPAR-γ agonist pioglitazone prevents apoptosis of endothelial progenitor cells from rat bone marrow.

Selective peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist affects the functions of endothelial progenitor cells (EPCs). This study explores the effect of selective PPAR-γ agonist, pioglitazone, on EPC apoptosis. The cells were cultured and identified via the double staining method in a medium containing different concentrations of pioglitazone. EPC apoptosis was detected by flow cytometry. On Day 7, EPCs engulfed DiL-ac-LDL and FITC-UEA-1, and showed yellow fluorescence in a laser-scanning confocal microscope. EPC apoptosis inhibition was maximal at 50 µmol/L. The ability of pioglitazone to prevent EPC apoptosis may be mediated by the PI3K/Akt signal pathway. The use of thiazolidine two ketone (TZD) to reduce EPC apoptosis may have some potential in treating vascular diseases.

Tubular actin filaments in tobacco guard cells.

The dynamic remodeling of actin filaments in guard cells functions in stomatal movement regulation. In our previous study, we found that the stochastic dynamics of guard cell actin filaments play a role in chloroplast movement during stomatal movement. In our present study, we further find that tubular actin filaments are present in tobacco guard cells that express GFP-mouse talin; approximately 2.3 tubular structures per cell with a diameter and height in the range of 1-3 µm and 3-5 µm, respectively. Most of the tubular structures were found to be localized in the cytoplasm near the inner walls of the guard cells. Moreover, the tubular actin filaments altered their localization slowly in the guard cells of static stoma, but showed obvious remodeling, such as breakdown and re-formation, in moving guard cells. Tubular actin filaments were further found to be colocalized with the chloroplasts in guard cells, but their roles in stomatal movement regulation requires further investigation.